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Reyer H, Honerlagen H, Oster M, Ponsuksili S, Kuhla B, Wimmers K. Multi-tissue gene expression profiling of cows with a genetic predisposition for low and high milk urea levels. Anim Biotechnol 2024; 35:2322542. [PMID: 38426941 DOI: 10.1080/10495398.2024.2322542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Milk urea (MU) concentration is proposed as an indicator trait for breeding toward reduced nitrogen (N) emissions and leaching in dairy. We selected 20 German Holstein cows based on MU breeding values, with 10 cows each having low (LMUg) and high (HMUg) MU genetic predisposition. Using RNA-seq, we characterized these cows to unravel molecular pathways governing post-absorptive body N pools focusing on renal filtration and reabsorption of nitrogenous compounds, hepatic urea formation and mammary gland N excretion. While we observed minor adjustments in cellular energy metabolism in different tissues associated with different MU levels, no transcriptional differences in liver ammonia detoxification were detected, despite significant differences in MU between the groups. Differential expression of AQP3 and SLC38A2 in the kidney provides evidence for higher urea concentration in the collecting duct of LMU cows than HMU cows. The mammary gland exhibited the most significant differences, particularly in tricarboxylic acid (TCA) cycle genes, amino acid transport, tRNA binding, and casein synthesis. These findings suggest that selecting for lower MU could lead to altered urinary urea (UU) handling and changes in milk protein synthesis. However, given the genetic variability in N metabolism components, the long-term effectiveness of MU-based selection in reducing N emissions remains uncertain.
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Affiliation(s)
- Henry Reyer
- Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Hanne Honerlagen
- Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
- Animal Breeding and Genomics, Wageningen University and Research, Wageningen, The Netherlands
| | - Michael Oster
- Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Siriluck Ponsuksili
- Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Björn Kuhla
- Institute of Nutritional Physiology 'Oskar Kellner', Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Klaus Wimmers
- Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
- Faculty of Agriculture and Environmental Sciences, Professorship of Animal Breeding and Genetics, University of Rostock, Rostock, Germany
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2
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Wu Y, Foollee A, Chan AY, Hille S, Hauke J, Challis MP, Johnson JL, Yaron TM, Mynard V, Aung OH, Cleofe MAS, Huang C, Lim Kam Sian TCC, Rahbari M, Gallage S, Heikenwalder M, Cantley LC, Schittenhelm RB, Formosa LE, Smith GC, Okun JG, Müller OJ, Rusu PM, Rose AJ. Phosphoproteomics-directed manipulation reveals SEC22B as a hepatocellular signaling node governing metabolic actions of glucagon. Nat Commun 2024; 15:8390. [PMID: 39333498 PMCID: PMC11436942 DOI: 10.1038/s41467-024-52703-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 09/16/2024] [Indexed: 09/29/2024] Open
Abstract
The peptide hormone glucagon is a fundamental metabolic regulator that is also being considered as a pharmacotherapeutic option for obesity and type 2 diabetes. Despite this, we know very little regarding how glucagon exerts its pleiotropic metabolic actions. Given that the liver is a chief site of action, we performed in situ time-resolved liver phosphoproteomics to reveal glucagon signaling nodes. Through pathway analysis of the thousands of phosphopeptides identified, we reveal "membrane trafficking" as a dominant signature with the vesicle trafficking protein SEC22 Homolog B (SEC22B) S137 phosphorylation being a top hit. Hepatocyte-specific loss- and gain-of-function experiments reveal that SEC22B was a key regulator of glycogen, lipid and amino acid metabolism, with SEC22B-S137 phosphorylation playing a major role in glucagon action. Mechanistically, we identify several protein binding partners of SEC22B affected by glucagon, some of which were differentially enriched with SEC22B-S137 phosphorylation. In summary, we demonstrate that phosphorylation of SEC22B is a hepatocellular signaling node mediating the metabolic actions of glucagon and provide a rich resource for future investigations on the biology of glucagon action.
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Affiliation(s)
- Yuqin Wu
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Ashish Foollee
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Andrea Y Chan
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Susanne Hille
- Department of Internal Medicine V, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
- German Center for Cardiovascular Research (DZHK), Partner site Hamburg/Kiel/Lübeck, Kiel, Germany
| | - Jana Hauke
- Division of Inherited Metabolic Diseases, University Children's Hospital, Heidelberg, Germany
| | - Matthew P Challis
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Jared L Johnson
- Meyer Cancer Center, Weill Cornell Medicine, New York, USA
- Department of Cell Biology, Harvard Medical School, Boston, USA
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, USA
| | - Tomer M Yaron
- Meyer Cancer Center, Weill Cornell Medicine, New York, USA
- Englander Institute for Precision Medicine, Institute for Computational Biomedicine, Weill Cornell Medicine, New York, USA
- Columbia University Vagelos College of Physicians and Surgeons, New York, USA
| | - Victoria Mynard
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Okka H Aung
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Maria Almira S Cleofe
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Cheng Huang
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
- Monash Proteomics and Metabolomics Platform, Monash University, Victoria, Australia
| | | | - Mohammad Rahbari
- German Cancer Research Center (DKFZ), Division of Chronic Inflammation and Cancer, Im Neuenheimer Feld 280, Heidelberg, Germany
- University Hospital Mannheim, Medical Faculty Mannheim, University of Heidelberg, Department of Surgery, Theodor-Kutzer-Ufer 1-3, Heidelberg, Germany
- University Tuebingen, Faculty of Medicine, Institute for Interdisciplinary Research on Cancer Metabolism and Chronic Inflammation, M3-Research Center for Malignome, Metabolome and Microbiome, Otfried-Müller-Straße 37, Tübingen, Germany
| | - Suchira Gallage
- German Cancer Research Center (DKFZ), Division of Chronic Inflammation and Cancer, Im Neuenheimer Feld 280, Heidelberg, Germany
- University Tuebingen, Faculty of Medicine, Institute for Interdisciplinary Research on Cancer Metabolism and Chronic Inflammation, M3-Research Center for Malignome, Metabolome and Microbiome, Otfried-Müller-Straße 37, Tübingen, Germany
| | - Mathias Heikenwalder
- German Cancer Research Center (DKFZ), Division of Chronic Inflammation and Cancer, Im Neuenheimer Feld 280, Heidelberg, Germany
- University Tuebingen, Faculty of Medicine, Institute for Interdisciplinary Research on Cancer Metabolism and Chronic Inflammation, M3-Research Center for Malignome, Metabolome and Microbiome, Otfried-Müller-Straße 37, Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", Eberhard-Karls University, Tübingen, Germany
| | - Lewis C Cantley
- Meyer Cancer Center, Weill Cornell Medicine, New York, USA
- Department of Cell Biology, Harvard Medical School, Boston, USA
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, USA
| | - Ralf B Schittenhelm
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
- Monash Proteomics and Metabolomics Platform, Monash University, Victoria, Australia
| | - Luke E Formosa
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Greg C Smith
- School of Biomedical Sciences, University of New South Wales, Sydney, Australia
| | - Jürgen G Okun
- Division of Inherited Metabolic Diseases, University Children's Hospital, Heidelberg, Germany
| | - Oliver J Müller
- Department of Internal Medicine V, University Hospital of Schleswig-Holstein, Campus Kiel, Germany
- German Center for Cardiovascular Research (DZHK), Partner site Hamburg/Kiel/Lübeck, Kiel, Germany
| | - Patricia M Rusu
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia
| | - Adam J Rose
- Nutrient Metabolism & Signalling Laboratory, Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Monash University, Victoria, Australia.
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia.
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3
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Xu Y, Liu Q, Chen CW, Wang Q, Du T, Yu R, Zhou Q, Yang D, Wang MW. Absence of PNET formation and normal longevity in a mouse model of Mahvash disease. Heliyon 2024; 10:e35362. [PMID: 39170309 PMCID: PMC11336617 DOI: 10.1016/j.heliyon.2024.e35362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2024] [Accepted: 07/26/2024] [Indexed: 08/23/2024] Open
Abstract
Mahvash disease, a rare autosomal recessive metabolic disorder characterized by biallelic loss-of-function mutations in the glucagon receptor gene (GCGR), induces significant pancreatic hyperglucagonemia, resulting in α-cell hyperplasia and occasional hypoglycemia. Utilizing CRISPR-Cas9 technology, we engineered a mouse model, designated as Gcgr V369M/V369M, harboring a homozygous V369M substitution in the glucagon receptor (GCGR). Although wild-type (WT) and Gcgr V369M/V369M mice exhibited no discernible difference in appearance or weight, adult Gcgr V369M/V369M mice, approximately 12 months of age, displayed a notable decrease in fasting blood glucose levels and elevated the levels of cholesterol and low-density lipoprotein-cholesterol. Moreover, plasma amino acid levels such as alanine (Ala), proline (Pro) and arginine (Arg) were elevated in Gcgr V369M/V369M mice contributing to α-cell proliferation and hyperglucagonemia. Despite sustained α-cell hyperplasia and increased circulating glucagon levels in Gcgr V369M/V369M mice, metabolic disparities between the two groups gradually waned with age accompanied by a reduction in α-cell hyperplasia. Throughout the lifespan of the mice (up to approximately 30 months), pancreatic neuroendocrine tumors (PNETs) did not manifest. This prolonged observation of metabolic alterations in Gcgr V369M/V369M mice furnishes valuable insights for a deeper comprehension of mild Mahvash disease in humans.
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Affiliation(s)
- Yingna Xu
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Qiaofeng Liu
- School of Pharmacy, Fudan University, Shanghai, 201203, China
| | - Chuan-Wei Chen
- Research Center for Deepsea Bioresources, Sanya, Hainan, 572025, China
| | - Qiuying Wang
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Tianyuan Du
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
| | - Run Yu
- Division of Endocrinology, Diabetes, and Metabolism, David Geffen School of Medicine at UCLA, Los Angeles, CA, 90095, USA
| | - Qingtong Zhou
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
- Research Center for Deepsea Bioresources, Sanya, Hainan, 572025, China
| | - Dehua Yang
- Research Center for Deepsea Bioresources, Sanya, Hainan, 572025, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, 210023, China
- State Key Laboratory of Chemical Biology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
| | - Ming-Wei Wang
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
- Research Center for Deepsea Bioresources, Sanya, Hainan, 572025, China
- Department of Chemistry, School of Science, The University of Tokyo, Tokyo, 113-0033, Japan
- Engineering Research Center of Tropical Medicine Innovation and Transformation of Ministry of Education, School of Pharmacy, Hainan Medical University, Haikou, 570228, China
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Coate KC, Dai C, Singh A, Stanley J, Covington BA, Bradley A, Oladipupo F, Gong Y, Wisniewski S, Spears E, Poffenberger G, Bustabad A, Rodgers T, Dey N, Shultz LD, Greiner DL, Yan H, Powers AC, Chen W, Dean ED. Interruption of glucagon signaling augments islet non-alpha cell proliferation in SLC7A2- and mTOR-dependent manners. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.06.606926. [PMID: 39149351 PMCID: PMC11326219 DOI: 10.1101/2024.08.06.606926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
Objective Dysregulated glucagon secretion and inadequate functional beta cell mass are hallmark features of diabetes. While glucagon receptor (GCGR) antagonism ameliorates hyperglycemia and elicits beta cell regeneration in pre-clinical models of diabetes, it also promotes alpha and delta cell hyperplasia. We sought to investigate the mechanism by which loss of glucagon action impacts pancreatic islet non-alpha cells, and the relevance of these observations in a human islet context. Methods We used zebrafish, rodents, and transplanted human islets comprising six different models of interrupted glucagon signaling to examine their impact on delta and beta cell proliferation and mass. We also used models with global deficiency of the cationic amino acid transporter, SLC7A2, and mTORC1 inhibition via rapamycin, to determine whether amino acid-dependent nutrient sensing was required for islet non-alpha cell growth. Results Inhibition of glucagon signaling stimulated delta cell proliferation in mouse and transplanted human islets, and in mouse islets. This was rapamycin-sensitive and required SLC7A2. Likewise, gcgr deficiency augmented beta cell proliferation via SLC7A2- and mTORC1-dependent mechanisms in zebrafish and promoted cell cycle engagement in rodent beta cells but was insufficient to drive a significant increase in beta cell mass in mice. Conclusion Our findings demonstrate that interruption of glucagon signaling augments islet non-alpha cell proliferation in zebrafish, rodents, and transplanted human islets in a manner requiring SLC7A2 and mTORC1 activation. An increase in delta cell mass may be leveraged for future beta cell regeneration therapies relying upon delta cell reprogramming.
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Affiliation(s)
- Katie C. Coate
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN
| | - Chunhua Dai
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Ajay Singh
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Jade Stanley
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Brittney A. Covington
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Amber Bradley
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Favour Oladipupo
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Yulong Gong
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Scott Wisniewski
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Erick Spears
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Greg Poffenberger
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Alexandria Bustabad
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Tyler Rodgers
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Nandita Dey
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | | | - Dale L. Greiner
- Program in Molecular Medicine, Diabetes Center of Excellence, University of Massachusetts Chan Medical School, Worcester, MA
| | - Hai Yan
- REMD Biotherapeutics Inc., Camarillo, CA
| | - Alvin C. Powers
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN
| | - Wenbiao Chen
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - E. Danielle Dean
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
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5
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Kang Q, Jia J, Dean ED, Yuan H, Dai C, Li Z, Jiang F, Zhang XK, Powers AC, Chen W, Li M. ErbB3 is required for hyperaminoacidemia-induced pancreatic α cell hyperplasia. J Biol Chem 2024; 300:107499. [PMID: 38944125 PMCID: PMC11326907 DOI: 10.1016/j.jbc.2024.107499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 05/18/2024] [Accepted: 06/02/2024] [Indexed: 07/01/2024] Open
Abstract
Blood amino acid levels are maintained in a narrow physiological range. The pancreatic α cells have emerged as the primary aminoacidemia regulator through glucagon secretion to promote hepatic amino acid catabolism. Interruption of glucagon signaling disrupts the liver-α cells axis leading to hyperaminoacidemia, which triggers a compensatory rise in glucagon secretion and α cell hyperplasia. The mechanisms of hyperaminoacidemia-induced α cell hyperplasia remain incompletely understood. Using a mouse α cell line and in vivo studies in zebrafish and mice, we found that hyperaminoacidemia-induced α cell hyperplasia requires ErbB3 signaling. In addition to mechanistic target of rapamycin complex 1, another ErbB3 downstream effector signal transducer and activator of transcription 3 also plays a role in α cell hyperplasia. Mechanistically, ErbB3 may partner with ErbB2 to stimulate cyclin D2 and suppress p27 via mechanistic target of rapamycin complex 1 and signal transducer and activator of transcription 3. Our study identifies ErbB3 as a new regulator for hyperaminoacidemia-induced α cell proliferation and a critical component of the liver-α cells axis that regulates aminoacidemia.
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Affiliation(s)
- Qi Kang
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Jianxin Jia
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - E Danielle Dean
- Departments of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA; Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Hang Yuan
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Chunhua Dai
- Departments of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA; Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Zhehui Li
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Fuquan Jiang
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Xiao-Kun Zhang
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Alvin C Powers
- Departments of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA; Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; VA Tennessee Valley Healthcare System, Nashville, Tennessee, USA
| | - Wenbiao Chen
- Departments of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
| | - Mingyu Li
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China; State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, Xiamen University, Xiamen, China.
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6
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Merkhassine M, Coch RW, Frederick CE, Bennett LL, Peng SA, Morse B, Cummings BP, Loftus JP. Glucagon infusion alters the circulating metabolome and urine amino acid excretion in dogs. J Endocrinol 2024; 262:e240051. [PMID: 38814331 PMCID: PMC11301426 DOI: 10.1530/joe-24-0051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 05/30/2024] [Indexed: 05/31/2024]
Abstract
Glucagon plays a central role in amino acid (AA) homeostasis. The dog is an established model of glucagon biology, and recently, metabolomic changes in people associated with glucagon infusions have been reported. Glucagon also has effects on the kidney; however, changes in urinary AA concentrations associated with glucagon remain under investigation. Therefore, we aimed to fill these gaps in the canine model by determining the effects of glucagon on the canine plasma metabolome and measuring urine AA concentrations. Employing two constant rate glucagon infusions (CRI) - low-dose (CRI-LO: 3 ng/kg/min) and high-dose (CRI-HI: 50 ng/kg/min) on five research beagles, we monitored interstitial glucose and conducted untargeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) on plasma samples and urine AA concentrations collected pre- and post-infusion. The CRI-HI induced a transient glucose peak (90-120 min), returning near baseline by infusion end, while only the CRI-LO resulted in 372 significantly altered plasma metabolites, primarily reductions (333). Similarly, CRI-HI affected 414 metabolites, with 369 reductions, evidenced by distinct clustering post-infusion via data reduction (PCA and sPLS-DA). CRI-HI notably decreased circulating AA levels, impacting various AA-related and energy-generating metabolic pathways. Urine analysis revealed increased 3-methyl-l-histidine and glutamine, and decreased alanine concentrations post-infusion. These findings demonstrate glucagon's glucose-independent modulation of the canine plasma metabolome and highlight the dog's relevance as a translational model for glucagon biology. Understanding these effects contributes to managing dysregulated glucagon conditions and informs treatments impacting glucagon homeostasis.
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Affiliation(s)
- Michael Merkhassine
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
- VCA Colonial Animal Hospital, Ithaca, New York, USA
| | - Reilly W Coch
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
- Weill Cornell College of Medicine, New York, New York, USA
| | - Carol E Frederick
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
| | - Lucinda L Bennett
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
| | - Seth A Peng
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
- Fate Therapeutics, San Diego, California, USA
| | - Benjamin Morse
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
| | - Bethany P Cummings
- Center for Alimentary and Metabolic Science, Department of Surgery, School of Medicine, University of California, Davis, Sacramento, California, USA
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, California, USA
| | - John P Loftus
- Loftus Laboratory, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
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7
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Kajani S, Laker RC, Ratkova E, Will S, Rhodes CJ. Hepatic glucagon action: beyond glucose mobilization. Physiol Rev 2024; 104:1021-1060. [PMID: 38300523 DOI: 10.1152/physrev.00028.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 01/10/2024] [Accepted: 01/11/2024] [Indexed: 02/02/2024] Open
Abstract
Glucagon's ability to promote hepatic glucose production has been known for over a century, with initial observations touting this hormone as a diabetogenic agent. However, glucagon receptor agonism [when balanced with an incretin, including glucagon-like peptide 1 (GLP-1) to dampen glucose excursions] is now being developed as a promising therapeutic target in the treatment of metabolic diseases, like metabolic dysfunction-associated steatotic disease/metabolic dysfunction-associated steatohepatitis (MASLD/MASH), and may also have benefit for obesity and chronic kidney disease. Conventionally regarded as the opposing tag-team partner of the anabolic mediator insulin, glucagon is gradually emerging as more than just a "catabolic hormone." Glucagon action on glucose homeostasis within the liver has been well characterized. However, growing evidence, in part thanks to new and sensitive "omics" technologies, has implicated glucagon as more than just a "glucose liberator." Elucidation of glucagon's capacity to increase fatty acid oxidation while attenuating endogenous lipid synthesis speaks to the dichotomous nature of the hormone. Furthermore, glucagon action is not limited to just glucose homeostasis and lipid metabolism, as traditionally reported. Glucagon plays key regulatory roles in hepatic amino acid and ketone body metabolism, as well as mitochondrial turnover and function, indicating broader glucagon signaling consequences for metabolic homeostasis mediated by the liver. Here we examine the broadening role of glucagon signaling within the hepatocyte and question the current dogma, to appreciate glucagon as more than just that "catabolic hormone."
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Affiliation(s)
- Sarina Kajani
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
| | - Rhianna C Laker
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
| | - Ekaterina Ratkova
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Mölndal, Sweden
| | - Sarah Will
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
| | - Christopher J Rhodes
- Early Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gaithersburg, Maryland, United States
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8
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Hayashi Y. Advances in basic research on glucagon and alpha cells. Diabetol Int 2024; 15:348-352. [PMID: 39101161 PMCID: PMC11291817 DOI: 10.1007/s13340-024-00696-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 01/17/2024] [Indexed: 08/06/2024]
Abstract
The regulation of plasma amino acid levels by glucagon in humans first attracted the attention of researchers in the 1980s. Recent basic research using animal models of glucagon deficiency suggested that a major physiological role of glucagon is the regulation of amino acid metabolism rather than to increase blood glucose levels. In this regard, novel feedback regulatory mechanisms that are mediated by glucagon and amino acids have recently been described between islet alpha cells and the liver. Increasingly, hyperglucagonemia in humans with diabetes and/or nonalcoholic fatty liver diseases is reported to likely be a compensatory response to hepatic glucagon resistance. Severe glucagon resistance due to a glucagon receptor mutation in humans causes hyperaminoacidemia and islet alpha cell expansion combined with pancreatic hypertrophy. Notably, a recent report showed that the restoration of glucagon resistance by liver transplantation resolved not only hyperglucagonemia, but also pancreatic hypertrophy and other metabolic disorders. The mechanisms that regulate islet cell proliferation by amino acids largely remain unelucidated. Clarification of such mechanisms will increase our understanding of the pathophysiology of diseases related to glucagon.
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Affiliation(s)
- Yoshitaka Hayashi
- Department of Endocrinology, Research Institute of Environmental Medicine, Nagoya University, Chikusa-Ku, Nagoya, 464-8601 Japan
- Department of Endocrinology, Nagoya University Graduate School of Medicine, Nagoya University, Nagoya, Japan
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9
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Rix I, Lund AB, Garvey LF, Hansen CP, Chabanova E, Hartmann B, Holst JJ, Vilsbøll T, Van Hall G, Knop FK. Increased hepatic glucagon sensitivity in totally pancreatectomised patients. Eur J Endocrinol 2024; 190:446-457. [PMID: 38781444 DOI: 10.1093/ejendo/lvae054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 04/02/2024] [Accepted: 05/22/2024] [Indexed: 05/25/2024]
Abstract
OBJECTIVE The metabolic phenotype of totally pancreatectomised patients includes hyperaminoacidaemia and predisposition to hypoglycaemia and hepatic lipid accumulation. We aimed to investigate whether the loss of pancreatic glucagon may be responsible for these changes. METHODS Nine middle-aged, normal-weight totally pancreatectomised patients, nine patients with type 1 diabetes (C-peptide negative), and nine matched controls underwent two separate experimental days, each involving a 150-min intravenous infusion of glucagon (4 ng/kg/min) or placebo (saline) under fasting conditions while any basal insulin treatment was continued. RESULTS Glucagon infusion increased plasma glucagon to similar high physiological levels in all groups. The infusion increased hepatic glucose production and decreased plasma concentration of most amino acids in all groups, with more pronounced effects in the totally pancreatectomised patients compared with the other groups. Glucagon infusion diminished fatty acid re-esterification and tended to decrease plasma concentrations of fatty acids in the totally pancreatectomised patients but not in the type 1 diabetes patients. CONCLUSION Totally pancreatectomised patients were characterised by increased sensitivity to exogenous glucagon at the level of hepatic glucose, amino acid, and lipid metabolism, suggesting that the metabolic disturbances characterising these patients may be rooted in perturbed hepatic processes normally controlled by pancreatic glucagon.
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Affiliation(s)
- Iben Rix
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, 2900 Hellerup, Denmark
- Medical & Science, Zealand Pharma A/S, 2860 Søborg, Denmark
| | - Asger B Lund
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, 2900 Hellerup, Denmark
- Clinical Research, Steno Diabetes Center Copenhagen, 2730 Herlev, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Lars F Garvey
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, 2900 Hellerup, Denmark
| | - Carsten P Hansen
- Department of Surgery, Copenhagen University Hospital - Rigshospitalet, 2100 Copenhagen, Denmark
| | - Elizaveta Chabanova
- Department of Radiology, Copenhagen University Hospital - Herlev and Gentofte, 2730 Herlev, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Tina Vilsbøll
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, 2900 Hellerup, Denmark
- Clinical Research, Steno Diabetes Center Copenhagen, 2730 Herlev, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Gerrit Van Hall
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Copenhagen University Hospital - Rigshospitalet, 2100 Copenhagen, Denmark
| | - Filip K Knop
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, 2900 Hellerup, Denmark
- Clinical Research, Steno Diabetes Center Copenhagen, 2730 Herlev, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
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10
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Suppli MP, Høgedal A, Bagger JI, Chabanova E, van Hall G, Forman JL, Christensen MB, Albrechtsen NJW, Holst JJ, Knop FK. Signs of Glucagon Resistance After a 2-Week Hypercaloric Diet Intervention. J Clin Endocrinol Metab 2024; 109:955-967. [PMID: 37967235 DOI: 10.1210/clinem/dgad666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/06/2023] [Accepted: 11/13/2023] [Indexed: 11/17/2023]
Abstract
CONTEXT Hyperglucagonemia is observed in individuals with obesity and contributes to the hyperglycemia of patients with type 2 diabetes. Hyperglucagonemia may develop due to steatosis-induced hepatic glucagon resistance resulting in impaired hepatic amino acid turnover and ensuing elevations of circulating glucagonotropic amino acids. OBJECTIVE We evaluated whether glucagon resistance could be induced in healthy individuals by a hypercaloric diet intervention designed to increase hepatic fat content. METHODS We recruited 20 healthy male individuals to follow a hypercaloric diet and a sedentary lifestyle for 2 weeks. Amino acid concentrations in response to infusion of glucagon were assessed during a pancreatic clamp with somatostatin and basal insulin. The reversibility of any metabolic changes was assessed 8 weeks after the intervention. Hepatic steatosis was assessed by magnetic resonance spectroscopy. RESULTS The intervention led to increased hepatic fat content (382% [206%; 705%], P < .01). Glucagon infusion led to a decrease in the concentration of total amino acids on all experimental days, but the percentage change in total amino acids was reduced (-2.5% ± 0.5% vs -0.2% ± 0.7%, P = .015) and the average slope of the decline in the total amino acid concentration was less steep (-2.0 ± 1.2 vs -1.2 ± 0.3 μM/min, P = .016) after the intervention compared to baseline. The changes were normalized at follow-up. CONCLUSION Our results indicate that short-term unhealthy behavior, which increases hepatic fat content, causes a reversible resistance to the effect of glucagon on amino acid concentrations in healthy individuals, which may explain the hyperglucagonemia associated with obesity and diabetes.
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Affiliation(s)
- Malte Palm Suppli
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, DK-2900 Hellerup, Denmark
| | - Astrid Høgedal
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, DK-2900 Hellerup, Denmark
| | - Jonatan Ising Bagger
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, DK-2900 Hellerup, Denmark
- Steno Diabetes Center Copenhagen, DK-2730 Herlev, Denmark
| | - Elizaveta Chabanova
- Department of Radiology, Herlev Hospital, University of Copenhagen, DK-2730 Herlev, Denmark
| | - Gerrit van Hall
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - Julie Lyng Forman
- Section of Biostatistics, Department of Public Health, University of Copenhagen, DK-1353 Copenhagen, Denmark
| | - Mikkel Bring Christensen
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, DK-2900 Hellerup, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
- Department of Clinical Pharmacology, Bispebjerg Hospital, University of Copenhagen, DK-2400 Copenhagen, Denmark
- Copenhagen Center for Translational Research, Bispebjerg Hospital, University of Copenhagen, DK-2400 Copenhagen, Denmark
| | - Nicolai Jacob Wewer Albrechtsen
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, DK-2400 Copenhagen, Denmark
| | - Jens Juul Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Filip Krag Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, DK-2900 Hellerup, Denmark
- Steno Diabetes Center Copenhagen, DK-2730 Herlev, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
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11
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Wang MY, Zhang Z, Zhao S, Onodera T, Sun XN, Zhu Q, Li C, Li N, Chen S, Paredes M, Gautron L, Charron MJ, Marciano DK, Gordillo R, Drucker DJ, Scherer PE. Downregulation of the kidney glucagon receptor, essential for renal function and systemic homeostasis, contributes to chronic kidney disease. Cell Metab 2024; 36:575-597.e7. [PMID: 38237602 PMCID: PMC10932880 DOI: 10.1016/j.cmet.2023.12.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 09/10/2023] [Accepted: 12/19/2023] [Indexed: 02/12/2024]
Abstract
The glucagon receptor (GCGR) in the kidney is expressed in nephron tubules. In humans and animal models with chronic kidney disease, renal GCGR expression is reduced. However, the role of kidney GCGR in normal renal function and in disease development has not been addressed. Here, we examined its role by analyzing mice with constitutive or conditional kidney-specific loss of the Gcgr. Adult renal Gcgr knockout mice exhibit metabolic dysregulation and a functional impairment of the kidneys. These mice exhibit hyperaminoacidemia associated with reduced kidney glucose output, oxidative stress, enhanced inflammasome activity, and excess lipid accumulation in the kidney. Upon a lipid challenge, they display maladaptive responses with acute hypertriglyceridemia and chronic proinflammatory and profibrotic activation. In aged mice, kidney Gcgr ablation elicits widespread renal deposition of collagen and fibronectin, indicative of fibrosis. Taken together, our findings demonstrate an essential role of the renal GCGR in normal kidney metabolic and homeostatic functions. Importantly, mice deficient for kidney Gcgr recapitulate some of the key pathophysiological features of chronic kidney disease.
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Affiliation(s)
- May-Yun Wang
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Zhuzhen Zhang
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shangang Zhao
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Sam and Ann Barshop Institute for Longevity and Aging Studies, Division of Endocrinology, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Toshiharu Onodera
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Xue-Nan Sun
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Qingzhang Zhu
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chao Li
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Na Li
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shiuhwei Chen
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Megan Paredes
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Laurent Gautron
- Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Maureen J Charron
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Denise K Marciano
- Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ruth Gordillo
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Daniel J Drucker
- Lunenfeld-TanenbaumResearchInstitute, Mt. Sinai Hospital, Toronto, ON M5G1X5, Canada; Department of Medicine, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Philipp E Scherer
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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12
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Gandasi NR, Gao R, Kothegala L, Pearce A, Santos C, Acreman S, Basco D, Benrick A, Chibalina MV, Clark A, Guida C, Harris M, Johnson PRV, Knudsen JG, Ma J, Miranda C, Shigeto M, Tarasov AI, Yeung HY, Thorens B, Asterholm IW, Zhang Q, Ramracheya R, Ladds G, Rorsman P. GLP-1 metabolite GLP-1(9-36) is a systemic inhibitor of mouse and human pancreatic islet glucagon secretion. Diabetologia 2024; 67:528-546. [PMID: 38127123 PMCID: PMC10844371 DOI: 10.1007/s00125-023-06060-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 10/18/2023] [Indexed: 12/23/2023]
Abstract
AIMS/HYPOTHESIS Diabetes mellitus is associated with impaired insulin secretion, often aggravated by oversecretion of glucagon. Therapeutic interventions should ideally correct both defects. Glucagon-like peptide 1 (GLP-1) has this capability but exactly how it exerts its glucagonostatic effect remains obscure. Following its release GLP-1 is rapidly degraded from GLP-1(7-36) to GLP-1(9-36). We hypothesised that the metabolite GLP-1(9-36) (previously believed to be biologically inactive) exerts a direct inhibitory effect on glucagon secretion and that this mechanism becomes impaired in diabetes. METHODS We used a combination of glucagon secretion measurements in mouse and human islets (including islets from donors with type 2 diabetes), total internal reflection fluorescence microscopy imaging of secretory granule dynamics, recordings of cytoplasmic Ca2+ and measurements of protein kinase A activity, immunocytochemistry, in vivo physiology and GTP-binding protein dissociation studies to explore how GLP-1 exerts its inhibitory effect on glucagon secretion and the role of the metabolite GLP-1(9-36). RESULTS GLP-1(7-36) inhibited glucagon secretion in isolated islets with an IC50 of 2.5 pmol/l. The effect was particularly strong at low glucose concentrations. The degradation product GLP-1(9-36) shared this capacity. GLP-1(9-36) retained its glucagonostatic effects after genetic/pharmacological inactivation of the GLP-1 receptor. GLP-1(9-36) also potently inhibited glucagon secretion evoked by β-adrenergic stimulation, amino acids and membrane depolarisation. In islet alpha cells, GLP-1(9-36) led to inhibition of Ca2+ entry via voltage-gated Ca2+ channels sensitive to ω-agatoxin, with consequential pertussis-toxin-sensitive depletion of the docked pool of secretory granules, effects that were prevented by the glucagon receptor antagonists REMD2.59 and L-168049. The capacity of GLP-1(9-36) to inhibit glucagon secretion and reduce the number of docked granules was lost in alpha cells from human donors with type 2 diabetes. In vivo, high exogenous concentrations of GLP-1(9-36) (>100 pmol/l) resulted in a small (30%) lowering of circulating glucagon during insulin-induced hypoglycaemia. This effect was abolished by REMD2.59, which promptly increased circulating glucagon by >225% (adjusted for the change in plasma glucose) without affecting pancreatic glucagon content. CONCLUSIONS/INTERPRETATION We conclude that the GLP-1 metabolite GLP-1(9-36) is a systemic inhibitor of glucagon secretion. We propose that the increase in circulating glucagon observed following genetic/pharmacological inactivation of glucagon signalling in mice and in people with type 2 diabetes reflects the removal of GLP-1(9-36)'s glucagonostatic action.
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Affiliation(s)
- Nikhil R Gandasi
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
- Cell Metabolism Lab (GA-08), Department of Developmental Biology and Genetics, Indian Institute of Science, Bangalore, India
| | - Rui Gao
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Lakshmi Kothegala
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
| | - Abigail Pearce
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Cristiano Santos
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
| | - Samuel Acreman
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Davide Basco
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Anna Benrick
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
| | - Margarita V Chibalina
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Anne Clark
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Claudia Guida
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Matthew Harris
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Paul R V Johnson
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, Oxford, UK
- Biomedical Research Centre, Oxford National Institute for Health Research, Churchill Hospital, Oxford, UK
| | - Jakob G Knudsen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Jinfang Ma
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Caroline Miranda
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Makoto Shigeto
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Andrei I Tarasov
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK
| | - Ho Yan Yeung
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Bernard Thorens
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Ingrid W Asterholm
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden
| | - Quan Zhang
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Reshma Ramracheya
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Graham Ladds
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Patrik Rorsman
- Metabolic Physiology Unit, Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, Gothenburg, Sweden.
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK.
- Biomedical Research Centre, Oxford National Institute for Health Research, Churchill Hospital, Oxford, UK.
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK.
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13
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Yang Y, Wang S, Sheng C, Tan J, Chen J, Li T, Ma X, Sun H, Wang X, Zhou L. Branched-chain amino acid catabolic defect promotes α-cell proliferation via activating mTOR signaling. Mol Cell Endocrinol 2024; 582:112143. [PMID: 38158148 DOI: 10.1016/j.mce.2023.112143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/09/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
Elevated circulating level of branched-chain amino acids (BCAAs) is closely related to the development of type 2 diabetes. However, the role of BCAA catabolism in various tissues in maintaining glucose homeostasis remains largely unknown. Pancreatic α-cells have been regarded as amino acid sensors in recent years. Therefore, we generated α-cell specific branched-chain alpha-ketoacid dehydrogenase E1α subunit (BCKDHA) knockout (BCKDHA-αKO) mice to decipher the effects of BCAA catabolism in α-cells on whole-body energy metabolism. BCKDHA-αKO mice showed normal body weight, body fat, and energy expenditure. Plasma glucagon level and glucose metabolism also remained unchanged in BCKDHA-αKO mice. Whereas, the deletion of BCKDHA led to increased α-cell number due to elevated cell proliferation in neonatal mice. In vitro, only leucine among BCAAs promoted aTC1-6 cell proliferation, which was blocked by the agonist of BCAA catabolism BT2 and the inhibitor of mTOR Rapamycin. Like Rapamycin, BT2 attenuated leucine-stimulated phosphorylation of S6 in αTC1-6 cells. Elevated phosphorylation level of S6 protein in pancreatic α-cells was also observed in BCKDHA-αKO mice. These results suggest that local accumulated leucine due to defective BCAA catabolism promotes α-cell proliferation through mTOR signaling, which is insufficient to affect glucagon secretion and whole-body glucose homeostasis.
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Affiliation(s)
- Yulin Yang
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shushu Wang
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chunxiang Sheng
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jialin Tan
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Junmin Chen
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Tianjiao Li
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoqin Ma
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Haipeng Sun
- NHC Key Laboratory of Hormones and Development, Tianjin Key Laboratory of Metabolic Diseases, Center for Cardiovascular Diseases, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, Chu Hsien-I Memorial Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, 300134, China
| | - Xiao Wang
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Libin Zhou
- Department of Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai National Clinical Research Center for Metabolic Diseases, Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of the PR China, Shanghai National Center for Translational Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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14
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Xia R, Peng HF, Zhang X, Zhang HS. Comprehensive review of amino acid transporters as therapeutic targets. Int J Biol Macromol 2024; 260:129646. [PMID: 38272411 DOI: 10.1016/j.ijbiomac.2024.129646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024]
Abstract
The solute carrier (SLC) family, with more than 400 membrane-bound proteins, facilitates the transport of a wide array of substrates such as nutrients, ions, metabolites, and drugs across biological membranes. Amino acid transporters (AATs) are membrane transport proteins that mediate transfer of amino acids into and out of cells or cellular organelles. AATs participate in many important physiological functions including nutrient supply, metabolic transformation, energy homeostasis, redox regulation, and neurological regulation. Several AATs have been found to significantly impact the progression of human malignancies, and dysregulation of AATs results in metabolic reprogramming affecting tumor growth and progression. However, current clinical therapies that directly target AATs have not been developed. The purpose of this review is to highlight the structural and functional diversity of AATs, the molecular mechanisms in human diseases such as tumors, kidney diseases, and emerging therapeutic strategies for targeting AATs.
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Affiliation(s)
- Ran Xia
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China
| | - Hai-Feng Peng
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China
| | - Xing Zhang
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China
| | - Hong-Sheng Zhang
- College of Chemistry and Life Science, Beijing University of Technology, Pingleyuan 100(#), District of Chaoyang, Beijing 100124, China.
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15
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Sipos B. [Multiple neuroendocrine tumors of the pancreas]. PATHOLOGIE (HEIDELBERG, GERMANY) 2024; 45:28-34. [PMID: 38180510 DOI: 10.1007/s00292-023-01289-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/06/2023] [Indexed: 01/06/2024]
Abstract
Multiple neuroendocrine tumors (NET) of the pancreas often have a hereditary background. Sporadic and hereditary NET do not differ morphologically or with regard to their hormone expression. The most important clues for a hereditary background are provided by examination of the peritumoral pancreatic tissue, especially the morphology and hormone expression of the endocrine islets. Hyperplastic or dysplastic islets and microtumors with aberrant distribution of insulin and glucagon are the main features of hereditary NET. Morphological diagnosis of potentially hereditary NET has a relevant impact on the prognosis and clinical care of patients.
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Affiliation(s)
- Bence Sipos
- ENETS CoE, Medizinische Klinik, Innere Medizin VIII, Medizinische Onkologie und Pneumologie, Universitätsklinikum Tübingen, Otfried-Müller-Straße 14, 72076, Tübingen, Deutschland.
- Praxis für Pathologie und Molekularpathologie, Stuttgart, Deutschland.
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16
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Rix I, Johansen ML, Lund A, Suppli MP, Chabanova E, van Hall G, Holst JJ, Wewer Albrechtsen NJ, Kistorp C, Knop FK. Hyperglucagonaemia and amino acid alterations in individuals with type 2 diabetes and non-alcoholic fatty liver disease. Endocr Connect 2024; 13:e230161. [PMID: 37947763 PMCID: PMC10762555 DOI: 10.1530/ec-23-0161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 11/10/2023] [Indexed: 11/12/2023]
Abstract
Aims Hyperglucagonaemia contributes to the pathophysiology in type 2 diabetes (T2D), but the mechanisms behind the inappropriate glucagon secretion are not fully understood. Glucagon and amino acids are regulated in a feedback loop referred to as the liver-α cell axis. Individuals with non-alcoholic fatty liver disease (NAFLD) appear to be glucagon resistant, disrupting the liver-α cell axis resulting in hyperglucagonaemia and hyperaminoacidaemia. We investigated the associations between circulating glucagon, amino acids, and liver fat content in a cohort of individuals with T2D. Methods We included 110 individuals with T2D in this cross-sectional study. Liver fat content was quantified using 1H magnetic resonance spectroscopy (MRS). Associations between liver fat content and plasma glucagon and amino acids, respectively, were estimated in multivariate linear regression analyses. Results Individuals with NAFLD (n = 52) had higher plasma glucagon concentrations than individuals without NAFLD (n = 58). The positive association between plasma glucagon concentrations and liver fat content was confirmed in the multivariable regression analyses. Plasma concentrations of isoleucine and glutamate were increased, and glycine and serine concentrations were decreased in individuals with NAFLD. Concentrations of other amino acids were similar between individuals with and without NAFLD, and no clear association was seen between liver fat content and amino acids in the regression analyses. Conclusion MRS-diagnosed NAFLD in T2D is associated with hyperglucagonaemia and elevated plasma concentrations of isoleucine and glutamate and low plasma concentrations of glycine and serine. Whether NAFLD and glucagon resistance per se induce these changes remains to be elucidated.
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Affiliation(s)
- Iben Rix
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Zealand Pharma A/S, Søborg, Denmark
| | - Marie L Johansen
- Department of Medicine, Herlev Hospital, University of Copenhagen, Herlev, Denmark
| | - Asger Lund
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Malte P Suppli
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Elizaveta Chabanova
- Department of Radiology, Herlev Hospital, University of Copenhagen, Herlev, Denmark
| | - Gerrit van Hall
- Clinical Metabolomics Core Facility, Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Caroline Kistorp
- Department of Endocrinology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Steno Diabetes Center Copenhagen, Herlev, Denmark
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17
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Yang W, Jiang W, Guo S. Regulation of Macronutrients in Insulin Resistance and Glucose Homeostasis during Type 2 Diabetes Mellitus. Nutrients 2023; 15:4671. [PMID: 37960324 PMCID: PMC10647592 DOI: 10.3390/nu15214671] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 10/30/2023] [Accepted: 11/02/2023] [Indexed: 11/15/2023] Open
Abstract
Insulin resistance is an important feature of metabolic syndrome and a precursor of type 2 diabetes mellitus (T2DM). Overnutrition-induced obesity is a major risk factor for the development of insulin resistance and T2DM. The intake of macronutrients plays a key role in maintaining energy balance. The components of macronutrients distinctly regulate insulin sensitivity and glucose homeostasis. Precisely adjusting the beneficial food compound intake is important for the prevention of insulin resistance and T2DM. Here, we reviewed the effects of different components of macronutrients on insulin sensitivity and their underlying mechanisms, including fructose, dietary fiber, saturated and unsaturated fatty acids, and amino acids. Understanding the diet-gene interaction will help us to better uncover the molecular mechanisms of T2DM and promote the application of precision nutrition in practice by integrating multi-omics analysis.
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Affiliation(s)
| | | | - Shaodong Guo
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX 77843, USA; (W.Y.); (W.J.)
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18
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Zhang Y, Fang XM. The pan-liver network theory: From traditional chinese medicine to western medicine. CHINESE J PHYSIOL 2023; 66:401-436. [PMID: 38149555 DOI: 10.4103/cjop.cjop-d-22-00131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2023] Open
Abstract
In traditional Chinese medicine (TCM), the liver is the "general organ" that is responsible for governing/maintaining the free flow of qi over the entire body and storing blood. According to the classic five elements theory, zang-xiang theory, yin-yang theory, meridians and collaterals theory, and the five-viscera correlation theory, the liver has essential relationships with many extrahepatic organs or tissues, such as the mother-child relationships between the liver and the heart, and the yin-yang and exterior-interior relationships between the liver and the gallbladder. The influences of the liver to the extrahepatic organs or tissues have been well-established when treating the extrahepatic diseases from the perspective of modulating the liver by using the ancient classic prescriptions of TCM and the acupuncture and moxibustion. In modern medicine, as the largest solid organ in the human body, the liver has the typical functions of filtration and storage of blood; metabolism of carbohydrates, fats, proteins, hormones, and foreign chemicals; formation of bile; storage of vitamins and iron; and formation of coagulation factors. The liver also has essential endocrine function, and acts as an immunological organ due to containing the resident immune cells. In the perspective of modern human anatomy, physiology, and pathophysiology, the liver has the organ interactions with the extrahepatic organs or tissues, for example, the gut, pancreas, adipose, skeletal muscle, heart, lung, kidney, brain, spleen, eyes, skin, bone, and sexual organs, through the circulation (including hemodynamics, redox signals, hepatokines, metabolites, and the translocation of microbiota or its products, such as endotoxins), the neural signals, or other forms of pathogenic factors, under normal or diseases status. The organ interactions centered on the liver not only influence the homeostasis of these indicated organs or tissues, but also contribute to the pathogenesis of cardiometabolic diseases (including obesity, type 2 diabetes mellitus, metabolic [dysfunction]-associated fatty liver diseases, and cardio-cerebrovascular diseases), pulmonary diseases, hyperuricemia and gout, chronic kidney disease, and male and female sexual dysfunction. Therefore, based on TCM and modern medicine, the liver has the bidirectional interaction with the extrahepatic organ or tissue, and this established bidirectional interaction system may further interact with another one or more extrahepatic organs/tissues, thus depicting a complex "pan-hepatic network" model. The pan-hepatic network acts as one of the essential mechanisms of homeostasis and the pathogenesis of diseases.
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Affiliation(s)
- Yaxing Zhang
- Department of Physiology; Research Centre of Basic Integrative Medicine, School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong; Issue 12th of Guangxi Apprenticeship Education of Traditional Chinese Medicine (Shi-Cheng Class of Guangxi University of Chinese Medicine), College of Continuing Education, Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Xian-Ming Fang
- Department of Cardiology, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine (Guangxi Hospital of Integrated Chinese Medicine and Western Medicine, Ruikang Clinical Faculty of Guangxi University of Chinese Medicine), Guangxi University of Chinese Medicine, Nanning, Guangxi, China
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19
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Radzishevsky I, Odeh M, Bodner O, Zubedat S, Shaulov L, Litvak M, Esaki K, Yoshikawa T, Agranovich B, Li WH, Radzishevsky A, Gottlieb E, Avital A, Wolosker H. Impairment of serine transport across the blood-brain barrier by deletion of Slc38a5 causes developmental delay and motor dysfunction. Proc Natl Acad Sci U S A 2023; 120:e2302780120. [PMID: 37812701 PMCID: PMC10589673 DOI: 10.1073/pnas.2302780120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 09/08/2023] [Indexed: 10/11/2023] Open
Abstract
Brain L-serine is critical for neurodevelopment and is thought to be synthesized solely from glucose. In contrast, we found that the influx of L-serine across the blood-brain barrier (BBB) is essential for brain development. We identified the endothelial Slc38a5, previously thought to be a glutamine transporter, as an L-serine transporter expressed at the BBB in early postnatal life. Young Slc38a5 knockout (KO) mice exhibit developmental alterations and a decrease in brain L-serine and D-serine, without changes in serum or liver amino acids. Slc38a5-KO brains exhibit accumulation of neurotoxic deoxysphingolipids, synaptic and mitochondrial abnormalities, and decreased neurogenesis at the dentate gyrus. Slc38a5-KO pups exhibit motor impairments that are affected by the administration of L-serine at concentrations that replenish the serine pool in the brain. Our results highlight a critical role of Slc38a5 in supplying L-serine via the BBB for proper brain development.
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Affiliation(s)
- Inna Radzishevsky
- Department of Biochemistry, B. Rappaport Faculty of Medicine, Technion-Israel Institue of Technology, Haifa3109601, Israel
| | - Maali Odeh
- Department of Biochemistry, B. Rappaport Faculty of Medicine, Technion-Israel Institue of Technology, Haifa3109601, Israel
| | - Oded Bodner
- Department of Biochemistry, B. Rappaport Faculty of Medicine, Technion-Israel Institue of Technology, Haifa3109601, Israel
| | - Salman Zubedat
- Department of Occupational Therapy, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa3498838, Israel
| | - Lihi Shaulov
- Electron Microscopy Unit, B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa3109601, Israel
| | - Maxim Litvak
- Department of Biochemistry, B. Rappaport Faculty of Medicine, Technion-Israel Institue of Technology, Haifa3109601, Israel
| | - Kayoko Esaki
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto860-0082, Japan
| | - Takeo Yoshikawa
- Laboratory of Molecular Psychiatry, RIKEN Center for Brain Science, Saitama351-0198, Japan
| | - Bella Agranovich
- Laura and Isaac Perlmutter Metabolomics Center, B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa3109601, Israel
| | - Wen-Hong Li
- Department of Cell Biology and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX75390-9039
| | | | - Eyal Gottlieb
- Technion-Integrated Cancer Center, B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa3109601, Israel
| | - Avi Avital
- Department of Occupational Therapy, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa3498838, Israel
| | - Herman Wolosker
- Department of Biochemistry, B. Rappaport Faculty of Medicine, Technion-Israel Institue of Technology, Haifa3109601, Israel
- Laura and Isaac Perlmutter Metabolomics Center, B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa3109601, Israel
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20
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Kjeldsen SAS, Thomsen MN, Skytte MJ, Samkani A, Richter MM, Frystyk J, Magkos F, Hansen E, Thomsen HS, Holst JJ, Madsbad S, Haugaard SB, Krarup T, Wewer Albrechtsen NJ. Markers of Glucagon Resistance Improve With Reductions in Hepatic Steatosis and Body Weight in Type 2 Diabetes. J Endocr Soc 2023; 7:bvad122. [PMID: 37818402 PMCID: PMC10561012 DOI: 10.1210/jendso/bvad122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Indexed: 10/12/2023] Open
Abstract
Context Hyperglucagonemia may develop in type 2 diabetes due to obesity-prone hepatic steatosis (glucagon resistance). Markers of glucagon resistance (including the glucagon-alanine index) improve following diet-induced weight loss, but the partial contribution of lowering hepatic steatosis vs body weight is unknown. Objective This work aimed to investigate the dependency of body weight loss following a reduction in hepatic steatosis on markers of glucagon resistance in type 2 diabetes. Methods A post hoc analysis was conducted from 2 previously published randomized controlled trials. We investigated the effect of weight maintenance (study 1: isocaloric feeding) or weight loss (study 2: hypocaloric feeding), both of which induced reductions in hepatic steatosis, on markers of glucagon sensitivity, including the glucagon-alanine index measured using a validated enzyme-linked immunosorbent assay and metabolomics in 94 individuals (n = 28 in study 1; n = 66 in study 2). Individuals with overweight or obesity with type 2 diabetes were randomly assigned to a 6-week conventional diabetes (CD) or carbohydrate-reduced high-protein (CRHP) diet within both isocaloric and hypocaloric feeding-interventions. Results By design, weight loss was greater after hypocaloric compared to isocaloric feeding, but both diets caused similar reductions in hepatic steatosis, allowing us to investigate the effect of reducing hepatic steatosis with or without a clinically relevant weight loss on markers of glucagon resistance. The glucagon-alanine index improved following hypocaloric, but not isocaloric, feeding, independently of macronutrient composition. Conclusion Improvements in glucagon resistance may depend on body weight loss in patients with type 2 diabetes.
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Affiliation(s)
- Sasha A S Kjeldsen
- Department of Clinical Biochemistry, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Mads N Thomsen
- Department of Endocrinology, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
| | - Mads J Skytte
- Department of Endocrinology, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
| | - Amirsalar Samkani
- Department of Endocrinology, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
| | - Michael M Richter
- Department of Clinical Biochemistry, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Jan Frystyk
- Department of Endocrinology, Odense University Hospital, Odense, 5000, Denmark
| | - Faidon Magkos
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Frederiksberg, 1958, Denmark
| | - Elizaveta Hansen
- Department of Radiology, Copenhagen University Hospital-Herlev, Herlev, 2730, Denmark
| | - Henrik S Thomsen
- Department of Radiology, Copenhagen University Hospital-Herlev, Herlev, 2730, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Copenhagen University Hospital-Hvidovre, Hvidovre, 2650, Denmark
| | - Steen B Haugaard
- Department of Endocrinology, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
- Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
| | - Thure Krarup
- Department of Endocrinology, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Frederiksberg, 1958, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Clinical Biochemistry, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, 2400, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, 2200, Denmark
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21
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Riahi Y, Kogot-Levin A, Kadosh L, Agranovich B, Malka A, Assa M, Piran R, Avrahami D, Glaser B, Gottlieb E, Jackson F, Cerasi E, Bernal-Mizrachi E, Helman A, Leibowitz G. Hyperglucagonaemia in diabetes: altered amino acid metabolism triggers mTORC1 activation, which drives glucagon production. Diabetologia 2023; 66:1925-1942. [PMID: 37480416 DOI: 10.1007/s00125-023-05967-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 06/07/2023] [Indexed: 07/24/2023]
Abstract
AIM/HYPOTHESIS Hyperglycaemia is associated with alpha cell dysfunction, leading to dysregulated glucagon secretion in type 1 and type 2 diabetes; however, the mechanisms involved are still elusive. The nutrient sensor mammalian target of rapamycin complex 1 (mTORC1) plays a major role in the maintenance of alpha cell mass and function. We studied the regulation of alpha cell mTORC1 by nutrients and its role in the development of hyperglucagonaemia in diabetes. METHODS Alpha cell mTORC1 activity was assessed by immunostaining for phosphorylation of its downstream target, the ribosomal protein S6, and glucagon, followed by confocal microscopy on pancreatic sections and flow cytometry on dispersed human and mouse islets and the alpha cell line, αTC1-6. Metabolomics and metabolic flux were studied by 13C glucose labelling in 2.8 or 16.7 mmol/l glucose followed by LC-MS analysis. To study the role of mTORC1 in mediating hyperglucagonaemia in diabetes, we generated an inducible alpha cell-specific Rptor knockout in the Akita mouse model of diabetes and tested the effects on glucose tolerance by IPGTT and on glucagon secretion. RESULTS mTORC1 activity was increased in alpha cells from diabetic Akita mice in parallel to the development of hyperglycaemia and hyperglucagonaemia (two- to eightfold increase). Acute exposure of mouse and human islets to amino acids stimulated alpha cell mTORC1 (3.5-fold increase), whereas high glucose concentrations inhibited mTORC1 (1.4-fold decrease). The mTORC1 response to glucose was abolished in human and mouse diabetic alpha cells following prolonged islet exposure to high glucose levels, resulting in sustained activation of mTORC1, along with increased glucagon secretion. Metabolomics and metabolic flux analysis showed that exposure to high glucose levels enhanced glycolysis, glucose oxidation and the synthesis of glucose-derived amino acids. In addition, chronic exposure to high glucose levels increased the expression of Slc7a2 and Slc38a4, which encode amino acid transporters, as well as the levels of branched-chain amino acids and methionine cycle metabolites (~1.3-fold increase for both). Finally, conditional Rptor knockout in alpha cells from adult diabetic mice inhibited mTORC1, thereby inhibiting glucagon secretion (~sixfold decrease) and improving diabetes, despite persistent insulin deficiency. CONCLUSIONS/INTERPRETATION Alpha cell exposure to hyperglycaemia enhances amino acid synthesis and transport, resulting in sustained activation of mTORC1, thereby increasing glucagon secretion. mTORC1 therefore plays a major role in mediating alpha cell dysfunction in diabetes. DATA AVAILABILITY All sequencing data are available from the Gene Expression Omnibus (GEO) repository (accession no. GSE154126; https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE154126 ).
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Affiliation(s)
- Yael Riahi
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Aviram Kogot-Levin
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Liat Kadosh
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Bella Agranovich
- Laboratory for Metabolism in Health and Disease, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Assaf Malka
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Michael Assa
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Ron Piran
- The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Dana Avrahami
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- Department of Developmental Biology and Cancer Research, Hadassah Medical Center, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Benjamin Glaser
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Eyal Gottlieb
- Laboratory for Metabolism in Health and Disease, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
- Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Fields Jackson
- Department of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, Israel
| | - Erol Cerasi
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division of Endocrinology, Diabetes and Metabolism, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Aharon Helman
- Department of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot, Israel.
| | - Gil Leibowitz
- Diabetes Unit, Department of Endocrinology and Metabolism, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
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22
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Ueno S, Seino Y, Hidaka S, Nakatani M, Hitachi K, Murao N, Maeda Y, Fujisawa H, Shibata M, Takayanagi T, Iizuka K, Yabe D, Sugimura Y, Tsuchida K, Hayashi Y, Suzuki A. Blockade of glucagon increases muscle mass and alters fiber type composition in mice deficient in proglucagon-derived peptides. J Diabetes Investig 2023; 14:1045-1055. [PMID: 37300240 PMCID: PMC10445200 DOI: 10.1111/jdi.14032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 05/02/2023] [Accepted: 05/12/2023] [Indexed: 06/12/2023] Open
Abstract
AIMS/INTRODUCTION Glucagon is secreted from pancreatic α-cells and plays an important role in amino acid metabolism in liver. Various animal models deficient in glucagon action show hyper-amino acidemia and α-cell hyperplasia, indicating that glucagon contributes to feedback regulation between the liver and the α-cells. In addition, both insulin and various amino acids, including branched-chain amino acids and alanine, participate in protein synthesis in skeletal muscle. However, the effect of hyperaminoacidemia on skeletal muscle has not been investigated. In the present study, we examined the effect of blockade of glucagon action on skeletal muscle using mice deficient in proglucagon-derived peptides (GCGKO mice). MATERIALS AND METHODS Muscles isolated from GCGKO and control mice were analyzed for their morphology, gene expression and metabolites. RESULTS GCGKO mice showed muscle fiber hypertrophy, and a decreased ratio of type IIA and an increased ratio of type IIB fibers in the tibialis anterior. The expression levels of myosin heavy chain (Myh) 7, 2, 1 and myoglobin messenger ribonucleic acid were significantly lower in GCGKO mice than those in control mice in the tibialis anterior. GCGKO mice showed a significantly higher concentration of arginine, asparagine, serine and threonine in the quadriceps femoris muscles, and also alanine, aspartic acid, cysteine, glutamine, glycine and lysine, as well as four amino acids in gastrocnemius muscles. CONCLUSIONS These results show that hyperaminoacidemia induced by blockade of glucagon action in mice increases skeletal muscle weight and stimulates slow-to-fast transition in type II fibers of skeletal muscle, mimicking the phenotype of a high-protein diet.
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Affiliation(s)
- Shinji Ueno
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
| | - Yusuke Seino
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
- Yutaka Seino Distinguished Center for Diabetes ResearchKansai Electric Power Medical Research InstituteKyotoKyotoJapan
| | - Shihomi Hidaka
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
| | - Masashi Nakatani
- Faculty of RehabilitationSeijoh UniversityTokaiAichiJapan
- Institute for Comprehensive Medical ScienceFujita Health UniversityToyoakeAichiJapan
| | - Keisuke Hitachi
- Institute for Comprehensive Medical ScienceFujita Health UniversityToyoakeAichiJapan
| | - Naoya Murao
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
- Yutaka Seino Distinguished Center for Diabetes ResearchKansai Electric Power Medical Research InstituteKyotoKyotoJapan
| | - Yasuhiro Maeda
- Open Facility CenterFujita Health UniversityToyoakeAichiJapan
| | - Haruki Fujisawa
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
| | - Megumi Shibata
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
| | - Takeshi Takayanagi
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
| | - Katsumi Iizuka
- Department of Clinical NutritionFujita Health UniversityToyoakeAichiJapan
| | - Daisuke Yabe
- Yutaka Seino Distinguished Center for Diabetes ResearchKansai Electric Power Medical Research InstituteKyotoKyotoJapan
- Department of Diabetes, Endocrinology and MetabolismGifu University Graduate School of MedicineGifuGifuJapan
- Department of Rheumatology and Clinical ImmunologyGifu University Graduate School of MedicineGifuGifuJapan
- Center for One Medicine Innovative Translational ResearchGifu University Graduate School of MedicineGifuGifuJapan
- Center for Healthcare Information TechnologyTokai National Higher Education and Research SystemNagoyaAichiJapan
- Division of Molecular and Metabolic MedicineKobe University Graduate School of MedicineKobeHyogoJapan
| | - Yoshihisa Sugimura
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
| | - Kunihiro Tsuchida
- Institute for Comprehensive Medical ScienceFujita Health UniversityToyoakeAichiJapan
| | - Yoshitaka Hayashi
- Department of Endocrinology, Research Institute of Environmental MedicineNagoya UniversityNagoyaAichiJapan
- Department of EndocrinologyNagoya University Graduate School of MedicineNagoyaAichiJapan
| | - Atsushi Suzuki
- Departments of Endocrinology, Diabetes and MetabolismFujita Health University School of MedicineToyoakeAichiJapan
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23
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Armour SL, Stanley JE, Cantley J, Dean ED, Knudsen JG. Metabolic regulation of glucagon secretion. J Endocrinol 2023; 259:e230081. [PMID: 37523232 PMCID: PMC10681275 DOI: 10.1530/joe-23-0081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 07/31/2023] [Indexed: 08/01/2023]
Abstract
Since the discovery of glucagon 100 years ago, the hormone and the pancreatic islet alpha cells that produce it have remained enigmatic relative to insulin-producing beta cells. Canonically, alpha cells have been described in the context of glucagon's role in glucose metabolism in liver, with glucose as the primary nutrient signal regulating alpha cell function. However, current data reveal a more holistic model of metabolic signalling, involving glucagon-regulated metabolism of multiple nutrients by the liver and other tissues, including amino acids and lipids, providing reciprocal feedback to regulate glucagon secretion and even alpha cell mass. Here we describe how various nutrients are sensed, transported and metabolised in alpha cells, providing an integrative model for the metabolic regulation of glucagon secretion and action. Importantly, we discuss where these nutrient-sensing pathways intersect to regulate alpha cell function and highlight key areas for future research.
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Affiliation(s)
- Sarah L Armour
- Section for cell biology and physiology, Department of Biology, University of Copenhagen, DK
| | - Jade E. Stanley
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, USA
| | - James Cantley
- Division of Cellular and systems medicine, School of Medicine, University of Dundee, UK
| | - E. Danielle Dean
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, USA
- Division of Diabetes, Endocrinology, & Metabolism, Vanderbilt University Medical Center school of medicine, USA
| | - Jakob G Knudsen
- Section for cell biology and physiology, Department of Biology, University of Copenhagen, DK
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24
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Spears E, Stanley JE, Shou M, Yin L, Li X, Dai C, Bradley A, Sellick K, Poffenberger G, Coate KC, Shrestha S, Jenkins R, Sloop KW, Wilson KT, Attie AD, Keller MP, Chen W, Powers AC, Dean ED. Pancreatic islet α cell function and proliferation requires the arginine transporter SLC7A2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.10.552656. [PMID: 37645716 PMCID: PMC10461917 DOI: 10.1101/2023.08.10.552656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Interrupting glucagon signaling decreases gluconeogenesis and the fractional extraction of amino acids by liver from blood resulting in lower glycemia. The resulting hyperaminoacidemia stimulates α cell proliferation and glucagon secretion via a liver-α cell axis. We hypothesized that α cells detect and respond to circulating amino acids levels via a unique amino acid transporter repertoire. We found that Slc7a2ISLC7A2 is the most highly expressed cationic amino acid transporter in α cells with its expression being three-fold greater in α than β cells in both mouse and human. Employing cell culture, zebrafish, and knockout mouse models, we found that the cationic amino acid arginine and SLC7A2 are required for α cell proliferation in response to interrupted glucagon signaling. Ex vivo and in vivo assessment of islet function in Slc7a2-/- mice showed decreased arginine-stimulated glucagon and insulin secretion. We found that arginine activation of mTOR signaling and induction of the glutamine transporter SLC38A5 was dependent on SLC7A2, showing that both's role in α cell proliferation is dependent on arginine transport and SLC7A2. Finally, we identified single nucleotide polymorphisms in SLC7A2 associated with HbA1c. Together, these data indicate a central role for SLC7A2 in amino acid-stimulated α cell proliferation and islet hormone secretion.
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Affiliation(s)
- Erick Spears
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Biology, Belmont University, Nashville, TN
| | - Jade E. Stanley
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN
| | - Matthew Shou
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Linlin Yin
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN
| | - Xuan Li
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN
| | - Chunhua Dai
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Amber Bradley
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Katelyn Sellick
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Greg Poffenberger
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Katie C. Coate
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Shristi Shrestha
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Regina Jenkins
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Kyle W. Sloop
- Diabetes and Complications, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN
| | - Keith T. Wilson
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN
- Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, TN
- Program in Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN
| | - Alan D. Attie
- Department of Biochemistry, University of Wisconsin, Madison, WI
| | - Mark P. Keller
- Department of Biochemistry, University of Wisconsin, Madison, WI
| | - Wenbiao Chen
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN
| | - Alvin C. Powers
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN
| | - E. Danielle Dean
- Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
- Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN
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25
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Brooks EP, Sussel L. Not the second fiddle: α cell development, identity, and function in health and diabetes. J Endocrinol 2023; 258:e220297. [PMID: 37171828 PMCID: PMC10524258 DOI: 10.1530/joe-22-0297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 05/12/2023] [Indexed: 05/13/2023]
Abstract
Historic and emerging studies provide evidence for the deterioration of pancreatic α cell function and identity in diabetes mellitus. Increased access to human tissue and the availability of more sophisticated molecular technologies have identified key insights into how α cell function and identity are preserved in healthy conditions and how they become dysfunctional in response to stress. These studies have revealed evidence of impaired glucagon secretion, shifts in α cell electrophysiology, changes in α cell mass, dysregulation of α cell transcription, and α-to-β cell conversion prior to and during diabetes. In this review, we outline the current state of research on α cell identity in health and disease. Evidence in model organisms and humans suggests that in addition to β cell dysfunction, diabetes is associated with a fundamental dysregulation of α cell identity. Importantly, epigenetic studies have revealed that α cells retain more poised and open chromatin at key cell-specific and diabetes-dysregulated genes, supporting the model that the inherent epigenetic plasticity of α cells makes them susceptible to the transcriptional changes that potentiate the loss of identity and function seen in diabetes. Thus, additional research into the maintenance of α cell identity and function is critical to fully understanding diabetes. Furthermore, these studies suggest α cells could represent an alternative source of new β cells for diabetes treatment.
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Affiliation(s)
- Elliott P Brooks
- Barbara Davis Center for Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lori Sussel
- Barbara Davis Center for Diabetes, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA
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26
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Taurino G, Chiu M, Bianchi MG, Griffini E, Bussolati O. The SLC38A5/SNAT5 amino acid transporter: from pathophysiology to pro-cancer roles in the tumor microenvironment. Am J Physiol Cell Physiol 2023; 325:C550-C562. [PMID: 37458433 DOI: 10.1152/ajpcell.00169.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/11/2023] [Accepted: 07/11/2023] [Indexed: 08/09/2023]
Abstract
SLC38A5/SNAT5 is a system N transporter that can mediate net inward or outward transmembrane fluxes of neutral amino acids coupled with Na+ (symport) and H+ (antiport). Its preferential substrates are not only amino acids with side chains containing amide (glutamine and asparagine) or imidazole (histidine) groups, but also serine, glycine, and alanine are transported by the carrier. Expressed in the pancreas, intestinal tract, brain, liver, bone marrow, and placenta, it is regulated at mRNA and protein levels by mTORC1 and WNT/β-catenin pathways, and it is sensitive to pH, nutritional stress, inflammation, and hypoxia. SNAT5 expression has been found to be altered in pathological conditions such as chronic inflammatory diseases, gestational complications, chronic metabolic acidosis, and malnutrition. Growing experimental evidence shows that SNAT5 is overexpressed in several types of cancer cells. Moreover, recently published results indicate that SNAT5 expression in stromal cells can support the metabolic exchanges occurring in the tumor microenvironment of asparagine-auxotroph tumors. We review the functional role of the SNAT5 transporter in pathophysiology and propose that, due to its peculiar operational and regulatory features, SNAT5 may play important pro-cancer roles when expressed either in neoplastic or in stromal cells of glutamine-auxotroph tumors.NEW & NOTEWORTHY The transporter SLC38A5/SNAT5 provides net influx or efflux of glutamine, asparagine, and serine. These amino acids are of particular metabolic relevance in several conditions. Changes in transporter expression or activity have been described in selected types of human cancers, where SNAT5 can mediate amino acid exchanges between tumor and stromal cells, thus providing a potential therapeutic target. This is the first review that recapitulates the characteristics and roles of the transporter in physiology and pathology.
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Affiliation(s)
- Giuseppe Taurino
- Laboratory of General Pathology, Department of Medicine and Surgery, University of Parma, Parma, Italy
- MRH-Microbiome Research Hub, University of Parma, Parma, Italy
| | - Martina Chiu
- Laboratory of General Pathology, Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Massimiliano G Bianchi
- Laboratory of General Pathology, Department of Medicine and Surgery, University of Parma, Parma, Italy
- MRH-Microbiome Research Hub, University of Parma, Parma, Italy
| | - Erika Griffini
- Laboratory of General Pathology, Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Ovidio Bussolati
- Laboratory of General Pathology, Department of Medicine and Surgery, University of Parma, Parma, Italy
- MRH-Microbiome Research Hub, University of Parma, Parma, Italy
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27
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Lubaczeuski C, Bozadjieva-Kramer N, Louzada RA, Gittes GK, Leibowitz G, Bernal-Mizrachi E. Time-dependent effects of endogenous hyperglucagonemia on glucose homeostasis and hepatic glucagon action. JCI Insight 2023; 8:e162255. [PMID: 37140984 PMCID: PMC10393226 DOI: 10.1172/jci.insight.162255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 05/03/2023] [Indexed: 05/05/2023] Open
Abstract
Elevation of glucagon levels and increase in α cell proliferation is associated with states of hyperglycemia in diabetes. A better understanding of the molecular mechanisms governing glucagon secretion could have major implications for understanding abnormal responses to hypoglycemia in patients with diabetes and provide novel avenues for diabetes management. Using mice with inducible induction of Rheb1 in α cells (αRhebTg mice), we showed that short-term activation of mTORC1 signaling is sufficient to induce hyperglucagonemia through increased glucagon secretion. Hyperglucagonemia in αRhebTg mice was also associated with an increase in α cell size and mass expansion. This model allowed us to identify the effects of chronic and short-term hyperglucagonemia on glucose homeostasis by regulating glucagon signaling in the liver. Short-term hyperglucagonemia impaired glucose tolerance, which was reversible over time. Liver glucagon resistance in αRhebTg mice was associated with reduced expression of the glucagon receptor and genes involved in gluconeogenesis, amino acid metabolism, and urea production. However, only genes regulating gluconeogenesis returned to baseline upon improvement of glycemia. Overall, these studies demonstrate that hyperglucagonemia exerts a biphasic response on glucose metabolism: Short-term hyperglucagonemia lead to glucose intolerance, whereas chronic exposure to glucagon reduced hepatic glucagon action and improved glucose tolerance.
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Affiliation(s)
- Camila Lubaczeuski
- Department of Medicine, Division Endocrinology, Metabolism and Diabetes, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Nadejda Bozadjieva-Kramer
- Veterans Affairs Ann Arbor Healthcare System, Research Service, Ann Arbor, Michigan, USA
- Department of Surgery, University of Michigan, Ann Arbor, Michigan, USA
| | - Ruy A. Louzada
- Department of Medicine, Division Endocrinology, Metabolism and Diabetes, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - George K. Gittes
- Childrens Hospital, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Gil Leibowitz
- Diabetes Unit and Endocrine Service, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Ernesto Bernal-Mizrachi
- Department of Medicine, Division Endocrinology, Metabolism and Diabetes, Miller School of Medicine, University of Miami, Miami, Florida, USA
- Diabetes Unit and Endocrine Service, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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28
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Hamilton A, Eliasson L, Knudsen JG. Amino acids and the changing face of the α-cell. Peptides 2023:171039. [PMID: 37295651 DOI: 10.1016/j.peptides.2023.171039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/31/2023] [Accepted: 06/05/2023] [Indexed: 06/12/2023]
Abstract
Glucagon has long been defined by its glucogenic action and as a result α-cells have been characterised based largely on their interaction with glucose. Recent findings have challenged this preconception, bringing to the fore the significant role glucagon plays in amino acid breakdown and underlining the importance of amino acids in glucagon secretion. The challenge that remains is defining the mechanism that underlie these effects - understanding which amino acids are most important, how they act on the α-cell and how their actions integrate with other fuels such as glucose and fatty acids. This review will describe the current relationship between amino acids and glucagon and how we can use this knowledge to redefine the α-cell.
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Affiliation(s)
- Alexander Hamilton
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Denmark; Department of Clinical Sciences in Malmö, Islet Cell Exocytosis, Lund University Diabetes Centre, Lund University, Malmö, Sweden.
| | - Lena Eliasson
- Department of Clinical Sciences in Malmö, Islet Cell Exocytosis, Lund University Diabetes Centre, Lund University, Malmö, Sweden.
| | - Jakob G Knudsen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Denmark.
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29
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Yang W, Liao W, Li X, Ai W, Pan Q, Shen Z, Jiang W, Guo S. Hepatic p38α MAPK controls gluconeogenesis via FOXO1 phosphorylation at S273 during glucagon signalling in mice. Diabetologia 2023:10.1007/s00125-023-05916-5. [PMID: 37202506 DOI: 10.1007/s00125-023-05916-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 02/09/2023] [Indexed: 05/20/2023]
Abstract
AIMS/HYPOTHESIS Hyperglucagonaemia-stimulated hepatic glucose production (HGP) contributes to hyperglycaemia during type 2 diabetes. A better understanding of glucagon action is important to enable efficient therapies to be developed for the treatment of diabetes. Here, we aimed to investigate the role of p38 MAPK family members in glucagon-induced HGP and determine the underlying mechanisms by which p38 MAPK regulates glucagon action. METHODS p38α, β, γ and δ MAPK siRNAs were transfected into primary hepatocytes, followed by measurement of glucagon-induced HGP. Adeno-associated virus serotype 8 carrying p38α MAPK short hairpin RNA (shRNA) was injected into liver-specific Foxo1 knockout, liver-specific Irs1/Irs2 double knockout and Foxo1S273D knockin mice. Foxo1S273A knockin mice were fed a high-fat diet for 10 weeks. Pyruvate tolerance tests, glucose tolerance tests, glucagon tolerance tests and insulin tolerance tests were carried out in mice, liver gene expression profiles were analysed and serum triglyceride, insulin and cholesterol levels were measured. Phosphorylation of forkhead box protein O1 (FOXO1) by p38α MAPK in vitro was analysed by LC-MS. RESULTS We found that p38α MAPK, but not the other p38 isoforms, stimulates FOXO1-S273 phosphorylation and increases FOXO1 protein stability, promoting HGP in response to glucagon stimulation. In hepatocytes and mouse models, inhibition of p38α MAPK blocked FOXO1-S273 phosphorylation, decreased FOXO1 levels and significantly impaired glucagon- and fasting-induced HGP. However, the effect of p38α MAPK inhibition on HGP was abolished by FOXO1 deficiency or a Foxo1 point mutation at position 273 from serine to aspartic acid (Foxo1S273D) in both hepatocytes and mice. Moreover, an alanine mutation at position 273 (Foxo1S273A) decreased glucose production, improved glucose tolerance and increased insulin sensitivity in diet-induced obese mice. Finally, we found that glucagon activates p38α through exchange protein activated by cAMP 2 (EPAC2) signalling in hepatocytes. CONCLUSIONS/INTERPRETATION This study found that p38α MAPK stimulates FOXO1-S273 phosphorylation to mediate the action of glucagon on glucose homeostasis in both health and disease. The glucagon-induced EPAC2-p38α MAPK-pFOXO1-S273 signalling pathway is a potential therapeutic target for the treatment of type 2 diabetes.
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Affiliation(s)
- Wanbao Yang
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Wang Liao
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Xiaopeng Li
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Weiqi Ai
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Quan Pan
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Zheng Shen
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Wen Jiang
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Shaodong Guo
- Department of Nutrition, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA.
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30
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Kawamori D, Sasaki S. Newly discovered knowledge pertaining to glucagon and its clinical applications. J Diabetes Investig 2023. [PMID: 37052948 DOI: 10.1111/jdi.14009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 03/10/2023] [Indexed: 04/14/2023] Open
Abstract
Glucagon has been defined as an 'insulin counteracting hormone', which raises blood glucose levels. Recent progress in basic research has shown that glucagon is closely involved in glucose and amino acid metabolism. Additionally, its secretion is intricately, but precisely, regulated by various mechanisms involving molecules in addition to glucose, thus showing its critical role in systemic nutrient metabolism. An innovative dual-antibody-linked immunosorbent assay for glucagon that improves measurement accuracy has been developed, and substantial clinical findings have been obtained using this new system. This discovery expanded the pathophysiological significance of glucagon and accelerated the development of its clinical applications in diabetes.
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Grants
- 21K08576 Ministry of Education, Culture, Sports, Science, and Technology in Japan
- 21K20902 Ministry of Education, Culture, Sports, Science, and Technology in Japan
- 22K16395 Ministry of Education, Culture, Sports, Science, and Technology in Japan
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Affiliation(s)
- Dan Kawamori
- Medical Education Center, Faculty of Medicine, Osaka University, Osaka, Japan
- Postgraduate Medical Training Center, Osaka University Hospital, Osaka University, Osaka, Japan
- Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Shugo Sasaki
- Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan
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31
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Hædersdal S, Andersen A, Knop FK, Vilsbøll T. Revisiting the role of glucagon in health, diabetes mellitus and other metabolic diseases. Nat Rev Endocrinol 2023; 19:321-335. [PMID: 36932176 DOI: 10.1038/s41574-023-00817-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/17/2023] [Indexed: 03/19/2023]
Abstract
Insulin and glucagon exert opposing effects on glucose metabolism and, consequently, pancreatic islet β-cells and α-cells are considered functional antagonists. The intra-islet hypothesis has previously dominated the understanding of glucagon secretion, stating that insulin acts to inhibit the release of glucagon. By contrast, glucagon is a potent stimulator of insulin secretion and has been used to test β-cell function. Over the past decade, α-cells have received increasing attention due to their ability to stimulate insulin secretion from neighbouring β-cells, and α-cell-β-cell crosstalk has proven central for glucose homeostasis in vivo. Glucagon is not only the counter-regulatory hormone to insulin in glucose metabolism but also glucagon secretion is more susceptible to changes in the plasma concentration of certain amino acids than to changes in plasma concentrations of glucose. Thus, the actions of glucagon also include a central role in amino acid turnover and hepatic fat oxidation. This Review provides insights into glucagon secretion, with a focus on the local paracrine actions on glucagon and the importance of α-cell-β-cell crosstalk. We focus on dysregulated glucagon secretion in obesity, non-alcoholic fatty liver disease and type 2 diabetes mellitus. Lastly, the future potential of targeting hyperglucagonaemia and applying dual and triple receptor agonists with glucagon receptor-activating properties in combination with incretin hormone receptor agonism is discussed.
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Affiliation(s)
- Sofie Hædersdal
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark.
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark.
| | - Andreas Andersen
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
| | - Filip K Knop
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Tina Vilsbøll
- Clinical Research, Copenhagen University Hospital - Steno Diabetes Center Copenhagen, Herlev, Denmark.
- Center for Clinical Metabolic Research, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark.
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
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32
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Kjeldsen SAS, Richter MM, Jensen NJ, Nilsson MSD, Heinz N, Nybing JD, Linden FH, Høgh-Schmidt E, Boesen MP, Madsbad S, Vilstrup H, Schiødt FV, Møller A, Nørgaard K, Schmidt S, Rashu EB, Gluud LL, Haugaard SB, Holst JJ, Rungby J, Wewer Albrechtsen NJ. Development of a glucagon sensitivity test in humans: Pilot data and the GLUSENTIC study protocol. Peptides 2023; 161:170938. [PMID: 36596314 DOI: 10.1016/j.peptides.2022.170938] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/30/2022] [Accepted: 12/30/2022] [Indexed: 01/02/2023]
Abstract
A physiological feedback system exists between hepatocytes and the alpha cells, termed the liver-alpha cell axis and refers to the relationship between amino acid-stimulated glucagon secretion and glucagon-stimulated amino acid catabolism. Several reports indicate that non-alcoholic fatty liver disease (NAFLD) disrupts the liver-alpha cell axis, because of impaired glucagon receptor signaling (glucagon resistance). However, no experimental test exists to assess glucagon resistance in humans. The objective was to develop an experimental test to determine glucagon sensitivity with respect to amino acid and glucose metabolism in humans. The proposed glucagon sensitivity test (comprising two elements: 1) i.v. injection of 0.2 mg glucagon and 2) infusion of mixed amino acids 331 mg/hour/kg) is based on nine pilot studies which are presented. Calculation of a proposed glucagon sensitivity index with respect to amino acid catabolism is also described. Secondly, we describe a complete study protocol (GLUSENTIC) according to which the glucagon sensitivity test will be applied in a cross-sectional study currently taking place. 65 participants including 20 individuals with a BMI 18.6-25 kg/m2, 30 individuals with a BMI ≥ 25-40 kg/m2, and 15 individuals with type 1 diabetes with a BMI between 18.6 and 40 kg/m2 will be included. Participants will be grouped according to their degree of hepatic steatosis measured by whole-liver magnetic resonance imaging (MRI). The primary outcome measure will be differences in the glucagon sensitivity index between individuals with and without hepatic steatosis. Developing a glucagon sensitivity test and index may provide insight into the physiological and pathophysiological mechanism of glucagon action and glucagon-based therapies.
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Affiliation(s)
- Sasha A S Kjeldsen
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Bispebjerg, Denmark; Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Michael M Richter
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Bispebjerg, Denmark; Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicole J Jensen
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Malin S D Nilsson
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Niklas Heinz
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Janus D Nybing
- Department of Radiology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Frederik H Linden
- Department of Radiology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Erik Høgh-Schmidt
- Department of Radiology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Mikael P Boesen
- Department of Radiology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Hvidovre University Hospital, Hvidovre, Denmark
| | - Hendrik Vilstrup
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Andreas Møller
- Department of Gastroenterology and Gastrointestinal Surgery, Hvidovre University Hospital, Hvidovre, Denmark
| | - Kirsten Nørgaard
- Institute of Clinical Medicine, Faculty of Health Science, University of Copenhagen, Denmark; Steno Diabetes Center Copenhagen, Herlev, Denmark
| | | | - Elias B Rashu
- Department of Gastroenterology and Gastrointestinal Surgery, Hvidovre University Hospital, Hvidovre, Denmark
| | - Lise L Gluud
- Department of Gastroenterology and Gastrointestinal Surgery, Hvidovre University Hospital, Hvidovre, Denmark; Institute of Clinical Medicine, Faculty of Health Science, University of Copenhagen, Denmark
| | - Steen B Haugaard
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark; Institute of Clinical Medicine, Faculty of Health Science, University of Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen Rungby
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark; Steno Diabetes Center Copenhagen, Herlev, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Bispebjerg, Denmark; Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Farag MR, Abo-Al-Ela HG, Alagawany M, Azzam MM, El-Saadony MT, Rea S, Di Cerbo A, Nouh DS. Effect of Quercetin Nanoparticles on Hepatic and Intestinal Enzymes and Stress-Related Genes in Nile Tilapia Fish Exposed to Silver Nanoparticles. Biomedicines 2023; 11:663. [PMID: 36979642 PMCID: PMC10045288 DOI: 10.3390/biomedicines11030663] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/10/2023] [Accepted: 02/15/2023] [Indexed: 02/25/2023] Open
Abstract
Recently, nanotechnology has become an important research field involved in the improvement of animals' productivity, including aquaculture. In this field, silver nanoparticles (AgNPs) have gained interest as antibacterial, antiviral, and antifungal agents. On the other hand, their extensive use in other fields increased natural water pollution causing hazardous effects on aquatic organisms. Quercetin is a natural polyphenolic compound of many plants and vegetables, and it acts as a potent antioxidant and therapeutic agent in biological systems. The current study investigated the potential mitigative effect of quercetin nanoparticles (QNPs) against AgNPs-induced toxicity in Nile tilapia via investigating liver function markers, hepatic antioxidant status, apoptosis, and bioaccumulation of silver residues in hepatic tissue in addition to the whole-body chemical composition, hormonal assay, intestinal enzymes activity, and gut microbiota. Fish were grouped into: control fish, fish exposed to 1.98 mg L-1 AgNPs, fish that received 400 mg L-1 QNPs, and fish that received QNPs and AgNPs at the same concentrations. All groups were exposed for 60 days. The moisture and ash contents of the AgNP group were significantly higher than those of the other groups. In contrast, the crude lipid and protein decreased in the whole body. AgNPs significantly increased serum levels of ALT, AST, total cholesterol, and triglycerides and decreased glycogen and growth hormone (*** p < 0.001). The liver and intestinal enzymes' activities were significantly inhibited (*** p < 0.001), while the oxidative damage liver enzymes, intestinal bacterial and Aeromonas counts, and Ag residues in the liver were significantly increased (*** p < 0.001, and * p < 0.05). AgNPs also significantly upregulated the expression of hepatic Hsp70, caspase3, and p53 genes (* p < 0.05). These findings indicate the oxidative and hepatotoxic effects of AgNPs. QNPs enhanced and restored physiological parameters and health status under normal conditions and after exposure to AgNPs.
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Affiliation(s)
- Mayada R. Farag
- Forensic Medicine and Toxicology Department, Veterinary Medicine Faculty, Zagazig University, Zagazig 44519, Egypt
| | - Haitham G. Abo-Al-Ela
- Genetics and Biotechnology, Department of Aquaculture, Faculty of Fish Resources, Suez University, Suez 43518, Egypt
| | - Mahmoud Alagawany
- Poultry Department, Faculty of Agriculture, Zagazig University, Zagazig 44519, Egypt
| | - Mahmoud M. Azzam
- Department of Animal Production College of Food & Agriculture Sciences, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohamed T. El-Saadony
- Department of Agricultural Microbiology, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
| | - Stefano Rea
- School of Biosciences and Veterinary Medicine, University of Camerino, 62024 Matelica, Italy
| | - Alessandro Di Cerbo
- School of Biosciences and Veterinary Medicine, University of Camerino, 62024 Matelica, Italy
| | - Doaa S. Nouh
- Anatomy and Embryology Department, Veterinary Medicine Faculty, Zagazig University, Zagazig 44519, Egypt
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Sanches JM, Zhao LN, Salehi A, Wollheim CB, Kaldis P. Pathophysiology of type 2 diabetes and the impact of altered metabolic interorgan crosstalk. FEBS J 2023; 290:620-648. [PMID: 34847289 DOI: 10.1111/febs.16306] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 10/14/2021] [Accepted: 11/29/2021] [Indexed: 02/06/2023]
Abstract
Diabetes is a complex and multifactorial disease that affects millions of people worldwide, reducing the quality of life significantly, and results in grave consequences for our health care system. In type 2 diabetes (T2D), the lack of β-cell compensatory mechanisms overcoming peripherally developed insulin resistance is a paramount factor leading to disturbed blood glucose levels and lipid metabolism. Impaired β-cell functions and insulin resistance have been studied extensively resulting in a good understanding of these pathways but much less is known about interorgan crosstalk, which we define as signaling between tissues by secreted factors. Besides hormones and organokines, dysregulated blood glucose and long-lasting hyperglycemia in T2D is associated with changes in metabolism with metabolites from different tissues contributing to the development of this disease. Recent data suggest that metabolites, such as lipids including free fatty acids and amino acids, play important roles in the interorgan crosstalk during the development of T2D. In general, metabolic remodeling affects physiological homeostasis and impacts the development of T2D. Hence, we highlight the importance of metabolic interorgan crosstalk in this review to gain enhanced knowledge of the pathophysiology of T2D, which may lead to new therapeutic approaches to treat this disease.
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Affiliation(s)
| | - Li Na Zhao
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Albert Salehi
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Claes B Wollheim
- Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Philipp Kaldis
- Department of Clinical Sciences, Lund University, Malmö, Sweden
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Abstract
Plasma glucose is tightly regulated via the secretion of the two glucose-regulating hormones insulin and glucagon. Situated next to the insulin-secreting β-cells, the α-cells produce and secrete glucagon-one of the body's few blood glucose-increasing hormones. Diabetes is a bihormonal disorder, resulting from both inadequate insulin secretion and dysregulation of glucagon. The year 2023 marks the 100th anniversary of the discovery of glucagon, making it particularly timely to highlight the roles of this systemic metabolic messenger in health and disease.
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Affiliation(s)
- Patrick E MacDonald
- Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
- Metabolic Physiology, Institute of Neuroscience and Physiology, University of Göteborg, Gothenburg, Sweden.
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36
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Winther-Sørensen M, Holst JJ, Wewer Albrechtsen NJ. The feedback cycles between glucose, amino acids and lipids and alpha cell secretion and their role in metabolic fatty liver disease. Curr Opin Lipidol 2023; 34:27-31. [PMID: 36373738 DOI: 10.1097/mol.0000000000000857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE OF REVIEW Glucagon increases hepatic glucose production and in patients with metabolic diseases, glucagon secretion is increased contributing to diabetic hyperglycemia. This review explores the role of amino acids and lipids in the regulation of glucagon secretion and how it may be disturbed in metabolic diseases such as obesity and metabolic associated fatty liver disease (MAFLD). RECENT FINDINGS Human and animal studies have shown that MAFLD is associated with glucagon resistance towards amino acid catabolism, resulting in elevated plasma levels of amino acids. A recent clinical study showed that MAFLD is also associated with glucagon resistance towards lipid metabolism. In contrast, MAFLD may not decrease hepatic sensitivity to the stimulatory effects of glucagon on glucose production. SUMMARY Elevated plasma levels of amino acids and lipids associated with MAFLD may cause diabetogenic hyperglucagonemia. MAFLD and glucagon resistance may therefore be causally linked to hyperglycemia and the development of type 2 diabetes.
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Affiliation(s)
- Marie Winther-Sørensen
- Department of Biomedical Sciences
- NNF Center for Protein Research, Faculty of Health and Medical Sciences
| | | | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences
- NNF Center for Protein Research, Faculty of Health and Medical Sciences
- Department for Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
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Gong Y, Yang B, Zhang D, Zhang Y, Tang Z, Yang L, Coate KC, Yin L, Covington BA, Patel RS, Siv WA, Sellick K, Shou M, Chang W, Danielle Dean E, Powers AC, Chen W. Hyperaminoacidemia induces pancreatic α cell proliferation via synergism between the mTORC1 and CaSR-Gq signaling pathways. Nat Commun 2023; 14:235. [PMID: 36646689 PMCID: PMC9842633 DOI: 10.1038/s41467-022-35705-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 12/20/2022] [Indexed: 01/18/2023] Open
Abstract
Glucagon has emerged as a key regulator of extracellular amino acid (AA) homeostasis. Insufficient glucagon signaling results in hyperaminoacidemia, which drives adaptive proliferation of glucagon-producing α cells. Aside from mammalian target of rapamycin complex 1 (mTORC1), the role of other AA sensors in α cell proliferation has not been described. Here, using both genders of mouse islets and glucagon receptor (gcgr)-deficient zebrafish (Danio rerio), we show α cell proliferation requires activation of the extracellular signal-regulated protein kinase (ERK1/2) by the AA-sensitive calcium sensing receptor (CaSR). Inactivation of CaSR dampened α cell proliferation, which was rescued by re-expression of CaSR or activation of Gq, but not Gi, signaling in α cells. CaSR was also unexpectedly necessary for mTORC1 activation in α cells. Furthermore, coactivation of Gq and mTORC1 induced α cell proliferation independent of hyperaminoacidemia. These results reveal another AA-sensitive mediator and identify pathways necessary and sufficient for hyperaminoacidemia-induced α cell proliferation.
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Affiliation(s)
- Yulong Gong
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, 430072, China
| | - Bingyuan Yang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Dingdong Zhang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yue Zhang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Zihan Tang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Liu Yang
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Katie C Coate
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Linlin Yin
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Brittney A Covington
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Ravi S Patel
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Walter A Siv
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Katelyn Sellick
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Matthew Shou
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Wenhan Chang
- University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, 94158, USA
| | - E Danielle Dean
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
| | - Alvin C Powers
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Ave, Nashville, TN, 37232, USA
- VA Tennessee Valley Healthcare System, Nashville, TN, 37212, USA
| | - Wenbiao Chen
- Department of Molecular Physiology & Biophysics, Vanderbilt University, 2215 Garland Ave, Nashville, TN, 37232, USA.
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Pixner T, Stummer N, Schneider AM, Lukas A, Gramlinger K, Julian V, Thivel D, Mörwald K, Mangge H, Dalus C, Aigner E, Furthner D, Weghuber D, Maruszczak K. The relationship between glucose and the liver-alpha cell axis - A systematic review. Front Endocrinol (Lausanne) 2023; 13:1061682. [PMID: 36686477 PMCID: PMC9849557 DOI: 10.3389/fendo.2022.1061682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 12/13/2022] [Indexed: 01/06/2023] Open
Abstract
Until recently, glucagon was considered a mere antagonist to insulin, protecting the body from hypoglycemia. This notion changed with the discovery of the liver-alpha cell axis (LACA) as a feedback loop. The LACA describes how glucagon secretion and pancreatic alpha cell proliferation are stimulated by circulating amino acids. Glucagon in turn leads to an upregulation of amino acid metabolism and ureagenesis in the liver. Several increasingly common diseases (e.g., non-alcoholic fatty liver disease, type 2 diabetes, obesity) disrupt this feedback loop. It is important for clinicians and researchers alike to understand the liver-alpha cell axis and the metabolic sequelae of these diseases. While most of previous studies have focused on fasting concentrations of glucagon and amino acids, there is limited knowledge of their dynamics after glucose administration. The authors of this systematic review applied PRISMA guidelines and conducted PubMed searches to provide results of 8078 articles (screened and if relevant, studied in full). This systematic review aims to provide better insight into the LACA and its mediators (amino acids and glucagon), focusing on the relationship between glucose and the LACA in adult and pediatric subjects.
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Affiliation(s)
- Thomas Pixner
- Department of Pediatric and Adolescent Medicine, Salzkammergutklinikum Voecklabruck, Voecklabruck, Austria
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
| | - Nathalie Stummer
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
| | - Anna Maria Schneider
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
| | - Andreas Lukas
- Department of Pediatric and Adolescent Medicine, Salzkammergutklinikum Voecklabruck, Voecklabruck, Austria
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
| | - Karin Gramlinger
- Department of Pediatric and Adolescent Medicine, Salzkammergutklinikum Voecklabruck, Voecklabruck, Austria
| | - Valérie Julian
- Department of Sport Medicine and Functional Explorations, Diet and Musculoskeletal Health Team, Human Nutrition Research Center (CRNH), INRA, University Hospital of Clermont-Ferrand, University of Clermont Auvergne, Clermont-Ferrand, France
| | - David Thivel
- Laboratory of Metabolic Adaptations to Exercise under Physiological and Pathological Conditions (AME2P), University of Clermont Auvergne, Clermont-Ferrand, France
| | - Katharina Mörwald
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
| | - Harald Mangge
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - Christopher Dalus
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
| | - Elmar Aigner
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- First Department of Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Dieter Furthner
- Department of Pediatric and Adolescent Medicine, Salzkammergutklinikum Voecklabruck, Voecklabruck, Austria
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
| | - Daniel Weghuber
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
| | - Katharina Maruszczak
- Obesity Research Unit, Paracelsus Medical University, Salzburg, Austria
- Department of Pediatrics, Paracelsus Medical University, Salzburg, Austria
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Kalwat MA, Rodrigues-dos-Santos K, Binns DD, Wei S, Zhou A, Evans MR, Posner BA, Roth MG, Cobb MH. Small molecule glucagon release inhibitors with activity in human islets. Front Endocrinol (Lausanne) 2023; 14:1114799. [PMID: 37152965 PMCID: PMC10157210 DOI: 10.3389/fendo.2023.1114799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 04/07/2023] [Indexed: 05/09/2023] Open
Abstract
Purpose Type 1 diabetes (T1D) accounts for an estimated 5% of all diabetes in the United States, afflicting over 1.25 million individuals. Maintaining long-term blood glucose control is the major goal for individuals with T1D. In T1D, insulin-secreting pancreatic islet β-cells are destroyed by the immune system, but glucagon-secreting islet α-cells survive. These remaining α-cells no longer respond properly to fluctuating blood glucose concentrations. Dysregulated α-cell function contributes to hyper- and hypoglycemia which can lead to macrovascular and microvascular complications. To this end, we sought to discover small molecules that suppress α-cell function for their potential as preclinical candidate compounds. Prior high-throughput screening identified a set of glucagon-suppressing compounds using a rodent α-cell line model, but these compounds were not validated in human systems. Results Here, we dissociated and replated primary human islet cells and exposed them to 24 h treatment with this set of candidate glucagon-suppressing compounds. Glucagon accumulation in the medium was measured and we determined that compounds SW049164 and SW088799 exhibited significant activity. Candidate compounds were also counter-screened in our InsGLuc-MIN6 β-cell insulin secretion reporter assay. SW049164 and SW088799 had minimal impact on insulin release after a 24 h exposure. To further validate these hits, we treated intact human islets with a selection of the top candidates for 24 h. SW049164 and SW088799 significantly inhibited glucagon release into the medium without significantly altering whole islet glucagon or insulin content. In concentration-response curves SW088799 exhibited significant inhibition of glucagon release with an IC50 of 1.26 µM. Conclusion Given the set of tested candidates were all top hits from the primary screen in rodent α-cells, this suggests some conservation of mechanism of action between human and rodents, at least for SW088799. Future structure-activity relationship studies of SW088799 may aid in elucidating its protein target(s) or enable its use as a tool compound to suppress α-cell activity in vitro.
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Affiliation(s)
- Michael A. Kalwat
- Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, Indianapolis, IN, United States
- Indiana University School of Medicine, Center for Diabetes and Metabolic Diseases, Indianapolis, IN, United States
- *Correspondence: Michael A. Kalwat, ;
| | - Karina Rodrigues-dos-Santos
- Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, Indianapolis, IN, United States
| | - Derk D. Binns
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Shuguang Wei
- Department Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Anwu Zhou
- Department Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Matthew R. Evans
- Department Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Bruce A. Posner
- Department Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Michael G. Roth
- Department Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Melanie H. Cobb
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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40
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Peng Y, Chen W, Huang F, Geng M, Li X, Zhang F, Zhu W, Meng L, Holmdahl R, Xu J, Lu S. SLC38A6 expression in macrophages exacerbates pulmonary inflammation. Respir Res 2023; 24:33. [PMID: 36707853 PMCID: PMC9881254 DOI: 10.1186/s12931-023-02330-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/14/2023] [Indexed: 01/28/2023] Open
Abstract
Pulmonary inflammation involves complex changes of the immune cells, in which macrophages play important roles and their function might be influenced by metabolism. Slc38a6 acts as a carrier of nutrient for macrophages (Mφ) to exert the function. In this study, pneumonia patient blood was found up-regulated SLC38A6 expression, which correlated with monocytes number and white blood cell number. The similar result was also shown in LPS induced sepsis mice. To reveal the key role of Slc38a6, we used systemic and conditional knock-out mice. Either systemic or LyzCRE specific knock-out could alleviate the severity of sepsis mice, reduce the proinflammatory cytokine TNF-α and IL-1β expression in serum and decrease the monocytes number in bronchial alveolar lavage and peritoneal lavage via flow cytometry. In order to reveal the signal of up-regulated Slc38a6, the Tlr4 signal inhibitor TAK242 and TLR4 knock-out mice were used. By blocking Tlr4 signal in macrophages via TAK242, the expression of Slc38a6 was down-regulated synchronously, and the same results were also found in Tlr4 knock-out macrophages. However, in the overexpressed Slc38a6 macrophages, blocking Tlr4 signal via TAK242, 20% of the mRNA expression of IL-1β still could be expressed, indicating that up-regulated Slc38a6 participates in IL-1β expression process. Collectively, it is the first time showed that an amino acid transporter SLC38A6 up-regulated in monocytes/macrophages promotes activation in pulmonary inflammation. SLC38A6 might be a promising target molecule for pulmonary inflammation treatment.
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Affiliation(s)
- Yizhao Peng
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China
| | - Weichao Chen
- grid.452902.8First Department of Respiratory Diseases, Xi’an Children’s Hospital, The Affiliated Children’s Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710003 China
| | - Fumeng Huang
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China
| | - Manman Geng
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China ,grid.452672.00000 0004 1757 5804National Joint Engineering Research Center of Biodiagnostics and Biotherapy, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710004 China
| | - Xiaowei Li
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China ,grid.452672.00000 0004 1757 5804National Joint Engineering Research Center of Biodiagnostics and Biotherapy, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710004 China
| | - Fujun Zhang
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China
| | - Wenhua Zhu
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China
| | - Liesu Meng
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China
| | - Rikard Holmdahl
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China ,grid.452672.00000 0004 1757 5804National Joint Engineering Research Center of Biodiagnostics and Biotherapy, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710004 China ,grid.4714.60000 0004 1937 0626Section for Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 77 Stockholm, Sweden
| | - Jing Xu
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China
| | - Shemin Lu
- grid.43169.390000 0001 0599 1243Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi 710061 China ,grid.452902.8First Department of Respiratory Diseases, Xi’an Children’s Hospital, The Affiliated Children’s Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710003 China ,grid.43169.390000 0001 0599 1243Institute of Molecular and Translational Medicine (IMTM), and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Xi’an Jiaotong University Health Science Center, Xi’an, Shaanxi 710061 China ,grid.452672.00000 0004 1757 5804National Joint Engineering Research Center of Biodiagnostics and Biotherapy, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710004 China
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Gu L, Cui X, Lin X, Yang J, Wei R, Hong T, Yang K. γ-aminobutyric acid modulates α-cell hyperplasia but not β-cell regeneration induced by glucagon receptor antagonism in type 1 diabetic mice. Acta Diabetol 2023; 60:19-28. [PMID: 36129525 DOI: 10.1007/s00592-022-01970-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 09/01/2022] [Indexed: 01/07/2023]
Abstract
AIMS To investigate whether treatment with γ-aminobutyric acid (GABA) alone or in combination with glucagon receptor (GCGR) monoclonal antibody (mAb) exerted beneficial effects on β-cell mass and α-cell mass, and to explore the origins of the regenerated β-cells in mice with type 1 diabetes (T1D). METHODS Streptozotocin (STZ)-induced T1D mice were treated with intraperitoneal injection of GABA (250 μg/kg per day) and/or REMD 2.59 (a GCGR mAb, 5 mg/kg per week), or IgG dissolved in PBS for 8 weeks. Plasma hormone levels and islet cell morphology were evaluated by ELISA and immunofluorescence, respectively. The origins of the regenerated β-cells were analyzed by double-immunostaining, α-cell lineage-tracing and BrdU-tracing studies. RESULTS After the 8-week treatment, GABA or GCGR mAb alone or in combination ameliorated hyperglycemia in STZ-induced T1D mice. GCGR mAb upregulated plasma insulin level and increased β-cell mass, and GABA appeared to have similar effects in T1D mice. However, combination treatment did not reveal any additive or synergistic effect. Interestingly, the GCGR mAb-induced increment of plasma glucagon level and α-cell mass was attenuated by the combined treatment of GABA. In addition, duct-derived β-cell neogenesis and α-to-β cell conversion but not β-cell proliferation contributed to the increased β-cell mass in T1D mice. CONCLUSION These results suggested that GABA attenuated α-cell hyperplasia but did not potentiates β-cell regeneration induced by GCGR mAb in T1D mice. Our findings provide novel insights into a combination treatment strategy for β-cell regeneration in T1D.
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Affiliation(s)
- Liangbiao Gu
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China
- Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Xiaona Cui
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China
- Clinical Stem Cell Research Center, Peking University Third Hospital, Beijing, 100191, China
| | - Xiafang Lin
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China
| | - Jin Yang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China
- Clinical Stem Cell Research Center, Peking University Third Hospital, Beijing, 100191, China
| | - Rui Wei
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China
- Clinical Stem Cell Research Center, Peking University Third Hospital, Beijing, 100191, China
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China.
- Clinical Stem Cell Research Center, Peking University Third Hospital, Beijing, 100191, China.
| | - Kun Yang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, 100191, China.
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42
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Wang Z, Yemanyi F, Blomfield AK, Bora K, Huang S, Liu CH, Britton WR, Cho SS, Tomita Y, Fu Z, Ma JX, Li WH, Chen J. Amino acid transporter SLC38A5 regulates developmental and pathological retinal angiogenesis. eLife 2022; 11:e73105. [PMID: 36454214 PMCID: PMC9714971 DOI: 10.7554/elife.73105] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/17/2022] [Indexed: 12/03/2022] Open
Abstract
Amino acid (AA) metabolism in vascular endothelium is important for sprouting angiogenesis. SLC38A5 (solute carrier family 38 member 5), an AA transporter, shuttles neutral AAs across cell membrane, including glutamine, which may serve as metabolic fuel for proliferating endothelial cells (ECs) to promote angiogenesis. Here, we found that Slc38a5 is highly enriched in normal retinal vascular endothelium, and more specifically, in pathological sprouting neovessels. Slc38a5 is suppressed in retinal blood vessels from Lrp5-/- and Ndpy/- mice, both genetic models of defective retinal vascular development with Wnt signaling mutations. Additionally, Slc38a5 transcription is regulated by Wnt/β-catenin signaling. Genetic deficiency of Slc38a5 in mice substantially delays retinal vascular development and suppresses pathological neovascularization in oxygen-induced retinopathy modeling ischemic proliferative retinopathies. Inhibition of SLC38A5 in human retinal vascular ECs impairs EC proliferation and angiogenic function, suppresses glutamine uptake, and dampens vascular endothelial growth factor receptor 2. Together these findings suggest that SLC38A5 is a new metabolic regulator of retinal angiogenesis by controlling AA nutrient uptake and homeostasis in ECs.
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Affiliation(s)
- Zhongxiao Wang
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Felix Yemanyi
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Alexandra K Blomfield
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Kiran Bora
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Shuo Huang
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Chi-Hsiu Liu
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - William R Britton
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Steve S Cho
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Yohei Tomita
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Zhongjie Fu
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
| | - Jian-xing Ma
- Department of Biochemistry, Wake Forest University School of MedicineWinston-SalemUnited States
| | - Wen-hong Li
- Departments of Cell Biology and of Biochemistry, University of Texas Southwestern Medical CenterDallasUnited States
| | - Jing Chen
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical SchoolBostonUnited States
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43
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Goode RA, Hum JM, Kalwat MA. Therapeutic Strategies Targeting Pancreatic Islet β-Cell Proliferation, Regeneration, and Replacement. Endocrinology 2022; 164:6836713. [PMID: 36412119 PMCID: PMC9923807 DOI: 10.1210/endocr/bqac193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/16/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022]
Abstract
Diabetes results from insufficient insulin production by pancreatic islet β-cells or a loss of β-cells themselves. Restoration of regulated insulin production is a predominant goal of translational diabetes research. Here, we provide a brief overview of recent advances in the fields of β-cell proliferation, regeneration, and replacement. The discovery of therapeutic targets and associated small molecules has been enabled by improved understanding of β-cell development and cell cycle regulation, as well as advanced high-throughput screening methodologies. Important findings in β-cell transdifferentiation, neogenesis, and stem cell differentiation have nucleated multiple promising therapeutic strategies. In particular, clinical trials are underway using in vitro-generated β-like cells from human pluripotent stem cells. Significant challenges remain for each of these strategies, but continued support for efforts in these research areas will be critical for the generation of distinct diabetes therapies.
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Affiliation(s)
- Roy A Goode
- Division of Biomedical Sciences, College of Osteopathic Medicine, Marian University, Indianapolis, IN, USA
| | - Julia M Hum
- Division of Biomedical Sciences, College of Osteopathic Medicine, Marian University, Indianapolis, IN, USA
| | - Michael A Kalwat
- Correspondence: Michael A. Kalwat, PhD, Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, 1210 Waterway Blvd, Suite 2000, Indianapolis, IN 46202, USA. or
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Kang Q, Zheng J, Jia J, Xu Y, Bai X, Chen X, Zhang XK, Wong FS, Zhang C, Li M. Disruption of the glucagon receptor increases glucagon expression beyond α-cell hyperplasia in zebrafish. J Biol Chem 2022; 298:102665. [PMID: 36334626 PMCID: PMC9719020 DOI: 10.1016/j.jbc.2022.102665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 10/24/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022] Open
Abstract
The glucagon receptor (GCGR) is a potential target for diabetes therapy. Several emerging GCGR antagonism-based therapies are under preclinical and clinical development. However, GCGR antagonism, as well as genetically engineered GCGR deficiency in animal models, are accompanied by α-cell hyperplasia and hyperglucagonemia, which may limit the application of GCGR antagonism. To better understand the physiological changes in α cells following GCGR disruption, we performed single cell sequencing of α cells isolated from control and gcgr-/- (glucagon receptor deficient) zebrafish. Interestingly, beyond the α-cell hyperplasia, we also found that the expression of gcga, gcgb, pnoca, and several glucagon-regulatory transcription factors were dramatically increased in one cluster of gcgr-/- α cells. We further confirmed that glucagon mRNA was upregulated in gcgr-/- animals by in situ hybridization and that glucagon promoter activity was increased in gcgr-/-;Tg(gcga:GFP) reporter zebrafish. We also demonstrated that gcgr-/- α cells had increased glucagon protein levels and increased granules after GCGR disruption. Intriguingly, the increased mRNA and protein levels could be suppressed by treatment with high-level glucose or knockdown of the pnoca gene. In conclusion, these data demonstrated that GCGR deficiency not only induced α-cell hyperplasia but also increased glucagon expression in α cells, findings which provide more information about physiological changes in α-cells when the GCGR is disrupted.
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Affiliation(s)
- Qi Kang
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Jihong Zheng
- Fundamental Research Center, Shanghai YangZhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center), School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jianxin Jia
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Ying Xu
- Fundamental Research Center, Shanghai YangZhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center), School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xuanxuan Bai
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fundamental Research Center, Shanghai YangZhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center), School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xinhua Chen
- Key Laboratory of Biotechnology of Fujian Province, Institute of Oceanology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiao-Kun Zhang
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - F Susan Wong
- Division of Infection and Immunity, Cardiff University School of Medicine, Cardiff, UK
| | - Chao Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Mingyu Li
- School of Pharmaceutical Sciences and School of Life Sciences, Xiamen University, Xiamen, China; Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China.
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Elmelund E, Galsgaard KD, Johansen CD, Trammell SA, Bomholt AB, Winther-Sørensen M, Hunt JE, Sørensen CM, Kruse T, Lau JF, Grevengoed TJ, Holst JJ, Wewer Albrechtsen NJ. Opposing effects of chronic glucagon receptor agonism and antagonism on amino acids, hepatic gene expression, and alpha cells. iScience 2022; 25:105296. [PMID: 36325048 PMCID: PMC9618771 DOI: 10.1016/j.isci.2022.105296] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/29/2022] [Accepted: 09/30/2022] [Indexed: 01/09/2023] Open
Abstract
The pancreatic hormone, glucagon, is known to regulate hepatic glucose production, but recent studies suggest that its regulation of hepatic amino metabolism is equally important. Here, we show that chronic glucagon receptor activation with a long-acting glucagon analog increases amino acid catabolism and ureagenesis and causes alpha cell hypoplasia in female mice. Conversely, chronic glucagon receptor inhibition with a glucagon receptor antibody decreases amino acid catabolism and ureagenesis and causes alpha cell hyperplasia and beta cell loss. These effects were associated with the transcriptional regulation of hepatic genes related to amino acid uptake and catabolism and by the non-transcriptional modulation of the rate-limiting ureagenesis enzyme, carbamoyl phosphate synthetase-1. Our results support the importance of glucagon receptor signaling for amino acid homeostasis and pancreatic islet integrity in mice and provide knowledge regarding the long-term consequences of chronic glucagon receptor agonism and antagonism. Glucagon receptor agonism increases amino acid catabolism and hepatic CPS-1 activity Glucagon receptor signaling regulates the number of pancreatic alpha cells Glucagon regulates the hepatic transcription of genes involved in amino acid metabolism
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Affiliation(s)
- Emilie Elmelund
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Katrine D. Galsgaard
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Christian D. Johansen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Samuel A.J. Trammell
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Anna B. Bomholt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Marie Winther-Sørensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Jenna E. Hunt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Charlotte M. Sørensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Thomas Kruse
- Novo Nordisk A/S, Research Chemistry, Novo Nordisk Park, 2760 Måløv, Denmark
| | - Jesper F. Lau
- Novo Nordisk A/S, Research Chemistry, Novo Nordisk Park, 2760 Måløv, Denmark
| | - Trisha J. Grevengoed
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Jens J. Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Nicolai J. Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Department of Clinical Biochemistry, Bispebjerg & Frederiksberg Hospitals, University of Copenhagen, 2400 Bispebjerg, Denmark
- Corresponding author
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46
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Capozzi ME, D'Alessio DA, Campbell JE. The past, present, and future physiology and pharmacology of glucagon. Cell Metab 2022; 34:1654-1674. [PMID: 36323234 PMCID: PMC9641554 DOI: 10.1016/j.cmet.2022.10.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 08/23/2022] [Accepted: 09/30/2022] [Indexed: 11/07/2022]
Abstract
The evolution of glucagon has seen the transition from an impurity in the preparation of insulin to the development of glucagon receptor agonists for use in type 1 diabetes. In type 2 diabetes, glucagon receptor antagonists have been explored to reduce glycemia thought to be induced by hyperglucagonemia. However, the catabolic actions of glucagon are currently being leveraged to target the rise in obesity that paralleled that of diabetes, bringing the pharmacology of glucagon full circle. During this evolution, the physiological importance of glucagon advanced beyond the control of hepatic glucose production, incorporating critical roles for glucagon to regulate both lipid and amino acid metabolism. Thus, it is unsurprising that the study of glucagon has left several paradoxes that make it difficult to distill this hormone down to a simplified action. Here, we describe the history of glucagon from the past to the present and suggest some direction to the future of this field.
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Affiliation(s)
- Megan E Capozzi
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701, USA
| | - David A D'Alessio
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701, USA; Department of Medicine, Endocrinology Division, Duke University Medical Center, Durham, NC 27701, USA
| | - Jonathan E Campbell
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC 27701, USA; Department of Medicine, Endocrinology Division, Duke University Medical Center, Durham, NC 27701, USA; Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27701, USA.
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47
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Kawamori D, Kageyama Y, Tanaka T, Ishizaka Y, Hosoe S, Katakami N, Shimomura I. Characteristic changes in plasma glutamate levels and free amino acid profiles in Japanese patients with type 1 diabetes mellitus. J Diabetes Investig 2022; 14:111-121. [PMID: 36151993 PMCID: PMC9807144 DOI: 10.1111/jdi.13911] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/19/2022] [Accepted: 09/07/2022] [Indexed: 01/07/2023] Open
Abstract
AIMS/INTRODUCTION In addition to absolute insulin deficiency, dysregulated glucagon in type 1 diabetes is considered pathophysiologically important. Previously, we confirmed the presence of dysregulated glucagon in Japanese patients with type 1 diabetes, and found a significant correlation between plasma glucagon and blood urea nitrogen levels, suggesting an association between glucagon and amino acid metabolism. In this study, we evaluated plasma amino acid levels in Japanese patients with type 1 diabetes in the context of their functional relationship with glucagon. MATERIALS AND METHODS We assessed plasma free amino acid levels using liquid chromatography-mass spectrometry in 77 Japanese patients with type 1 diabetes, and statistically analyzed their characteristics and relationships with clinical parameters, including glucagon. RESULTS Participants with type 1 diabetes showed a large decrease in glutamate levels together with a characteristic change in plasma free amino acid profiles. The network structural prediction analyses showed correlations between each amino acid and glucagon in type 1 diabetes. CONCLUSIONS Participants with type 1 diabetes showed characteristic changes in plasma glutamate levels and free amino acid profiles compared with controls and type 2 diabetes patients. Glucagon showed a closer correlation with amino acids than with parameters of glucose metabolism, suggesting that type 1 diabetes includes dysregulation in amino acids through dysregulated glucagon from remaining pancreatic α-cells, together with that in glucose by insulin deficiency.
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Affiliation(s)
- Dan Kawamori
- Department of Metabolic Medicine, Graduate School of MedicineOsaka UniversityOsakaJapan,Medical Education Center, Faculty of MedicineOsaka UniversityOsakaJapan,Postgraduate Medical Training Center, Osaka University HospitalOsaka UniversityOsakaJapan
| | | | - Takayuki Tanaka
- Research and Business Planning DepartmentAjinomoto Co. IncTokyoJapan,Research Institute for Bioscience Products and Fine ChemicalsAjinomoto Co. Inc.Kawasaki, KanagawaJapan
| | - Yuko Ishizaka
- Center for Multiphasic Health Testing and ServicesMitsui Memorial HospitalTokyoJapan
| | - Shigero Hosoe
- Department of Metabolic Medicine, Graduate School of MedicineOsaka UniversityOsakaJapan
| | - Naoto Katakami
- Department of Metabolic Medicine, Graduate School of MedicineOsaka UniversityOsakaJapan
| | - Iichiro Shimomura
- Department of Metabolic Medicine, Graduate School of MedicineOsaka UniversityOsakaJapan
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Richter MM, Galsgaard KD, Elmelund E, Knop FK, Suppli MP, Holst JJ, Winther-Sørensen M, Kjeldsen SA, Wewer Albrechtsen NJ. The Liver-α-Cell Axis in Health and in Disease. Diabetes 2022; 71:1852-1861. [PMID: 35657688 PMCID: PMC9862287 DOI: 10.2337/dbi22-0004] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 05/19/2022] [Indexed: 02/05/2023]
Abstract
Glucagon and insulin are the main regulators of blood glucose. While the actions of insulin are extensively mapped, less is known about glucagon. Besides glucagon's role in glucose homeostasis, there are additional links between the pancreatic α-cells and the hepatocytes, often collectively referred to as the liver-α-cell axis, that may be of importance for health and disease. Thus, glucagon receptor antagonism (pharmacological or genetic), which disrupts the liver-α-cell axis, results not only in lower fasting glucose but also in reduced amino acid turnover and dyslipidemia. Here, we review the actions of glucagon on glucose homeostasis, amino acid catabolism, and lipid metabolism in the context of the liver-α-cell axis. The concept of glucagon resistance is also discussed, and we argue that the various elements of the liver-α-cell axis may be differentially affected in metabolic diseases such as diabetes, obesity, and nonalcoholic fatty liver disease (NAFLD). This conceptual rethinking of glucagon biology may explain why patients with type 2 diabetes have hyperglucagonemia and how NAFLD disrupts the liver-α-cell axis, compromising the normal glucagon-mediated enhancement of substrate-induced amino acid turnover and possibly fatty acid β-oxidation. In contrast to amino acid catabolism, glucagon-induced glucose production may not be affected by NAFLD, explaining the diabetogenic effect of NAFLD-associated hyperglucagonemia. Consideration of the liver-α-cell axis is essential to understanding the complex pathophysiology underlying diabetes and other metabolic diseases.
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Affiliation(s)
- Michael M. Richter
- Department of Clinical Biochemistry, Diagnostic Center, Copenhagen University Hospital—Rigshospitalet, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Katrine D. Galsgaard
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emilie Elmelund
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip K. Knop
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Steno Diabetes Center Copenhagen, Herlev, Denmark
| | - Malte P. Suppli
- Center for Clinical Metabolic Research, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - Jens J. Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marie Winther-Sørensen
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sasha A.S. Kjeldsen
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J. Wewer Albrechtsen
- Department of Clinical Biochemistry, Diagnostic Center, Copenhagen University Hospital—Rigshospitalet, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Biochemistry, Copenhagen University Hospital—Bispebjerg and Frederiksberg Hospital, Bispebjerg, Denmark
- Corresponding author: Nicolai J. Wewer Albrechtsen,
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49
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Moon JH, Lee S, Pak M, Hur B, Kim S. MLDEG: A Machine Learning Approach to Identify Differentially Expressed Genes Using Network Property and Network Propagation. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2022; 19:2356-2364. [PMID: 33750713 DOI: 10.1109/tcbb.2021.3067613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
MOTIVATION Identifying differentially expressed genes (DEGs) in transcriptome data is a very important task. However, performances of existing DEG methods vary significantly for data sets measured in different conditions and no single statistical or machine learning model for DEG detection perform consistently well for data sets of different traits. In addition, setting a cutoff value for the significance of differential expressions is one of confounding factors to determine DEGs. RESULTS We address these problems by developing an ensemble model that refines the heterogeneous and inconsistent results of the existing methods by taking accounts into network information such as network propagation and network property. DEG candidates that are predicted with weak evidence by the existing tools are re-classified by our proposed ensemble model for the transcriptome data. Tested on 10 RNA-seq datasets downloaded from gene expression omnibus (GEO), our method showed excellent performance of winning the first place in detecting ground truth (GT) genes in eight datasets and find almost all GT genes in six datasets. On the other hand, performances of all existing methods varied significantly for the 10 data sets. Because of the design principle, our method can accommodate any new DEG methods naturally. AVAILABILITY The source code of our method is available at https://github.com/jihmoon/MLDEG.
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50
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Glucagon-receptor-antagonism-mediated β-cell regeneration as an effective anti-diabetic therapy. Cell Rep 2022; 39:110872. [PMID: 35649369 DOI: 10.1016/j.celrep.2022.110872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 02/12/2022] [Accepted: 05/04/2022] [Indexed: 01/10/2023] Open
Abstract
Type 1 diabetes mellitus (T1D) is a chronic disease with potentially severe complications, and β-cell deficiency underlies this disease. Despite active research, no therapy to date has been able to induce β-cell regeneration in humans. Here, we discover the β-cell regenerative effects of glucagon receptor antibody (anti-GcgR). Treatment with anti-GcgR in mouse models of β-cell deficiency leads to reversal of hyperglycemia, increase in plasma insulin levels, and restoration of β-cell mass. We demonstrate that both β-cell proliferation and α- to β-cell transdifferentiation contribute to anti-GcgR-induced β-cell regeneration. Interestingly, anti-GcgR-induced α-cell hyperplasia can be uncoupled from β-cell regeneration after antibody clearance from the body. Importantly, we are able to show that anti-GcgR-induced β-cell regeneration is also observed in non-human primates. Furthermore, anti-GcgR and anti-CD3 combination therapy reverses diabetes and increases β-cell mass in a mouse model of autoimmune diabetes.
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