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Yin X, Ni G, Zhang X, Fu S, Li H, Gao Z. Tyrosine nitration of glucagon impairs its function: Extending the role of heme in T2D pathogenesis. J Inorg Biochem 2024; 255:112519. [PMID: 38507994 DOI: 10.1016/j.jinorgbio.2024.112519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/24/2024] [Accepted: 03/04/2024] [Indexed: 03/22/2024]
Abstract
New studies raise the possibility that the higher glucagon (GCG) level present in type 2 diabetes (T2D) is a compensatory mechanism to enhance β-cell function, rather than induce dysregulated glucose homeostasis, due to an important role for GCG that acts directly within the pancreas on insulin secretion by intra-islet GCG signaling. However, in states of poorly controlled T2D, pancreatic α cell mass increases (overproduced GCG) in response to insufficient insulin secretion, indicating decreased local GCG activity. The reason for this decrease is not clear. Recent evidence has uncovered a new role of heme in cellular signal transduction, and its mechanism involves reversible binding of heme to proteins. Considering that protein tyrosine nitration in diabetic islets increases and glucose-stimulated insulin secretion (GSIS) decreases, we speculated that heme modulates GSIS by transient interaction with GCG and catalyzing its tyrosine nitration, and the tyrosine nitration may impair GCG activity, leading to loss of intra-islet GCG signaling and markedly impaired insulin secretion. Data presented here elucidate a novel role for heme in disrupting local GCG signaling in diabetes. Heme bound to GCG and induced GCG tyrosine nitration. Two tyrosine residues in GCG were both sensitive to the nitrating species. Further, GCG was also demonstrated to be a preferred target peptide for tyrosine nitration by co-incubation with BSA. Tyrosine nitration impaired GCG stimulated cAMP-dependent signaling in islet β cells and decreased insulin release. Our results provided a new role of heme for impaired GSIS in the pathological process of diabetes.
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Affiliation(s)
- Xiaoying Yin
- Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Wuhan 430074, PR China; School of Chemistry and Chemical Engineering, Huazhong University of Science & Technology, Wuhan 430074, PR China
| | - Guoqi Ni
- Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Wuhan 430074, PR China; School of Chemistry and Chemical Engineering, Huazhong University of Science & Technology, Wuhan 430074, PR China
| | - Xuan Zhang
- Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Wuhan 430074, PR China; School of Chemistry and Chemical Engineering, Huazhong University of Science & Technology, Wuhan 430074, PR China
| | - Shitao Fu
- Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Wuhan 430074, PR China; School of Chemistry and Chemical Engineering, Huazhong University of Science & Technology, Wuhan 430074, PR China
| | - Hailing Li
- Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Wuhan 430074, PR China; School of Chemistry and Chemical Engineering, Huazhong University of Science & Technology, Wuhan 430074, PR China.
| | - Zhonghong Gao
- Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Wuhan 430074, PR China; School of Chemistry and Chemical Engineering, Huazhong University of Science & Technology, Wuhan 430074, PR China.
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Nakamura Y, Horie I, Kitamura T, Kusunoki Y, Nishida K, Yamamoto A, Hirota Y, Fukui T, Maeda Y, Minami M, Matsui T, Kawakami A, Abiru N. Glucagon secretion and its association with glycaemic control and ketogenesis during sodium-glucose cotransporter 2 inhibition by ipragliflozin in people with type 1 diabetes: Results from the multicentre, open-label, prospective study. Diabetes Obes Metab 2024; 26:1605-1614. [PMID: 38253809 DOI: 10.1111/dom.15458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/27/2023] [Accepted: 01/04/2024] [Indexed: 01/24/2024]
Abstract
AIM Clinical trials showed the efficacy of sodium-glucose cotransporter 2 inhibitors for type 1 diabetes (T1D) by significant reductions in body weight and glycaemic variability, but elevated susceptibility to ketoacidosis via elevated glucagon secretion was a potential concern. The Suglat-AID evaluated glucagon responses and its associations with glycaemic control and ketogenesis before and after T1D treatment with the sodium-glucose cotransporter 2 inhibitor, ipragliflozin. METHODS Adults with T1D (n = 25) took 50-mg open-labelled ipragliflozin daily as adjunctive to insulin. Laboratory/clinical data including continuous glucose monitoring were collected until 12 weeks after the ipragliflozin initiation. The participants underwent a mixed-meal tolerance test (MMTT) twice [before (first MMTT) and 12 weeks after ipragliflozin treatment (second MMTT)] to evaluate responses of glucose, C-peptide, glucagon and β-hydroxybutyrate. RESULTS The area under the curve from fasting (0 min) to 120 min (AUC0-120min) of glucagon in second MMTT were significantly increased by 14% versus first MMTT. The fasting and postprandial β-hydroxybutyrate levels were significantly elevated in second MMTT versus first MMTT. The positive correlation between postprandial glucagon secretion and glucose excursions observed in first MMTT disappeared in second MMTT, but a negative correlation between fasting glucagon and time below range (glucose, <3.9 mmol/L) appeared in second MMTT. The percentage changes in glucagon levels (fasting and AUC0-120min) from baseline to 12 weeks were significantly correlated with those in β-hydroxybutyrate levels. CONCLUSIONS Ipragliflozin treatment for T1D increased postprandial glucagon secretion, which did not exacerbate postprandial hyperglycaemia but might protect against hypoglycaemia, leading to reduced glycaemic variability. The increased glucagon secretion might accelerate ketogenesis when adequate insulin is not supplied.
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Affiliation(s)
- Yuta Nakamura
- Department of Endocrinology and Metabolism, Division of Advanced Preventive Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Ichiro Horie
- Department of Endocrinology and Metabolism, Division of Advanced Preventive Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Tadahiro Kitamura
- Metabolic Signal Research Center, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Yoshiki Kusunoki
- Department of Diabetes, Endocrinology and Clinical Immunology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Kenro Nishida
- Division of Diabetes and Endocrinology, Kumamoto Central Hospital, Kumamoto, Japan
| | - Akane Yamamoto
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yushi Hirota
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tomoyasu Fukui
- Division of Diabetes, Metabolism, and Endocrinology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Yasutaka Maeda
- Minami Diabetes Clinical Research Center, Clinic Masae Minami, Fukuoka, Japan
| | - Masae Minami
- Minami Diabetes Clinical Research Center, Clinic Masae Minami, Fukuoka, Japan
| | - Takanori Matsui
- Faculty of Bioscience and Biotechnology, Fukui Prefectural University, Fukui, Japan
| | - Atsushi Kawakami
- Department of Endocrinology and Metabolism, Division of Advanced Preventive Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Norio Abiru
- Department of Endocrinology and Metabolism, Division of Advanced Preventive Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Deshmukh NJ, Kalshetti MS, Patil M, Autade P, Sangle GV. Exploring the modulatory effects of sotagliflozin on dyslipidemia in mice: The role of glucagon, fibroblast growth factor 21 and glucagon-like peptide 1. Clin Exp Pharmacol Physiol 2024; 51:e13854. [PMID: 38527859 DOI: 10.1111/1440-1681.13854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 02/19/2024] [Accepted: 03/05/2024] [Indexed: 03/27/2024]
Abstract
Sotagliflozin is the first dual SGLT1/2 inhibitor antidiabetic drug approved by the US Food and Drug Administration for the management of heart failure. SGLT1/2 inhibition is observed to potentiate the secretion of the incretin hormone, glucagon-like peptide-1 (GLP-1). The current preclinical research sought to investigate the effect of sotagliflozin on the secretion of fat-regulating peptides such as GLP-1, glucagon and fibroblast growth factor 21 (FGF21) and their prospective association with sotagliflozin's potential beneficial effects on dyslipidaemia. During an oral fat tolerance test in mice, sotagliflozin substantially increased GLP-1 and insulin concentrations. Although sotagliflozin alone did not ameliorate postprandial lipemia, its combination with linagliptin (DPP-IV inhibitor) significantly improved lipid tolerance comparable to orlistat (lipase inhibitor). In a triton-induced hypertriglyceridemia model, sotagliflozin, along with other medications (fenofibrate, exenatide and linagliptin) reduced fat excursion; however, co-administration with linagliptin provided no extra advantage. Furthermore, sotagliflozin stimulated glucagon secretion in the alpha TC1.6 cells and healthy mice, which resulted in an increased circulating FGF21 and β-hydroxybutyrate concentration. Finally, chronic treatment of sotagliflozin in high-fat diet (HFD)-fed obese mice resulted in reduced body weight gain, liver triglyceride, cholesterol, interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) levels compared with the placebo group. However, the addition of linagliptin did not provide any additional benefit. In conclusion, sotagliflozin was found to have an effect on GLP-1 and also stimulate the release of glucagon and FGF21, which are important for regulating fat metabolism. Therefore, sotagliflozin might represent a potential therapeutic approach for the treatment of diabetic dyslipidemia and steatohepatitis.
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Affiliation(s)
- Nitin J Deshmukh
- D.S.T.S. Mandal's Collage of Pharmacy, Solapur, India
- Wockhardt Research Centre, Aurangabad, India
| | - M S Kalshetti
- D.S.T.S. Mandal's Collage of Pharmacy, Solapur, India
| | - Mohan Patil
- Wockhardt Research Centre, Aurangabad, India
| | | | - Ganesh V Sangle
- Wockhardt Research Centre, Aurangabad, India
- Kashiv BioSciences Private Limited, Ahmedabad, India
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Coate KC, Ramnanan CJ, Smith M, Winnick JJ, Kraft G, Irimia-Dominguez J, Farmer B, Donahue EP, Roach PJ, Cherrington AD, Edgerton DS. Integration of metabolic flux with hepatic glucagon signaling and gene expression profiles in the conscious dog. Am J Physiol Endocrinol Metab 2024; 326:E428-E442. [PMID: 38324258 DOI: 10.1152/ajpendo.00316.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/24/2024] [Accepted: 01/26/2024] [Indexed: 02/08/2024]
Abstract
Glucagon rapidly and profoundly stimulates hepatic glucose production (HGP), but for reasons that are unclear, this effect normally wanes after a few hours, despite sustained plasma glucagon levels. This study characterized the time course of glucagon-mediated molecular events and their relevance to metabolic flux in the livers of conscious dogs. Glucagon was either infused into the hepato-portal vein at a sixfold basal rate in the presence of somatostatin and basal insulin, or it was maintained at a basal level in control studies. In one control group, glucose remained at basal, whereas in the other, glucose was infused to match the hyperglycemia that occurred in the hyperglucagonemic group. Elevated glucagon caused a rapid (30 min) and largely sustained increase in hepatic cAMP over 4 h, a continued elevation in glucose-6-phosphate (G6P), and activation and deactivation of glycogen phosphorylase and synthase activities, respectively. Net hepatic glycogenolysis increased rapidly, peaking at 15 min due to activation of the cAMP/PKA pathway, then slowly returned to baseline over the next 3 h in line with allosteric inhibition by glucose and G6P. Glucagon's stimulatory effect on HGP was sustained relative to the hyperglycemic control group due to continued PKA activation. Hepatic gluconeogenic flux did not increase due to the lack of glucagon's effect on substrate supply to the liver. Global gene expression profiling highlighted glucagon-regulated activation of genes involved in cellular respiration, metabolic processes, and signaling, as well as downregulation of genes involved in extracellular matrix assembly and development.NEW & NOTEWORTHY Glucagon rapidly stimulates hepatic glucose production, but these effects are transient. This study links the molecular and metabolic flux changes that occur in the liver over time in response to a rise in glucagon, demonstrating the strength of the dog as a translational model to couple findings in small animals and humans. In addition, this study clarifies why the rapid effects of glucagon on liver glycogen metabolism are not sustained.
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Affiliation(s)
- Katie C Coate
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States
| | - Christopher J Ramnanan
- Department of Innovation in Medical Education, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada
| | - Marta Smith
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Jason J Winnick
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States
| | - Guillaume Kraft
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Jose Irimia-Dominguez
- Department of Molecular and Cellular Endocrinology, Beckman Research Institute, Duarte, California, United States
| | - Ben Farmer
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - E Patrick Donahue
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States
| | - Peter J Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Alan D Cherrington
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Dale S Edgerton
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
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Shiozaki‐Takagi Y, Ozaki N, Toyoda Y. Epac2 activation mediates glucagon-induced glucogenesis in primary rat hepatocytes. J Diabetes Investig 2024; 15:429-436. [PMID: 38243676 PMCID: PMC10981141 DOI: 10.1111/jdi.14142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/06/2023] [Accepted: 12/21/2023] [Indexed: 01/21/2024] Open
Abstract
AIMS/INTRODUCTION Glucagon plays an essential role in hepatic glucogenesis by enhancing glycogen breakdown, inducing gluconeogenesis, and suppressing glycogenesis. Moreover, glucagon increases cyclic adenosine monophosphate (cAMP) levels, thereby activating protein kinase A (PKA) and cAMP guanine nucleotide exchange factor (also known as Epac). Although the function of PKA in the liver has been studied extensively, the function of hepatic Epac is poorly understood. The aim of this study was to elucidate the role of Epac in mediating the action of glucagon on the hepatocytes. MATERIALS AND METHODS Epac mRNA and protein expression, localization, and activity in the hepatocytes were analyzed by reverse transcription polymerase chain reaction, western blotting, immunofluorescence staining, and Rap1 activity assay, respectively. Additionally, we investigated the effects of an Epac-specific activator, 8-CPT, and an Epac-specific inhibitor, ESI-05, on glycogen metabolism in isolated rat hepatocytes. Further mechanisms of glycogen metabolism were evaluated by examining glucokinase (GK) translocation and mRNA expression of gluconeogenic enzymes. RESULTS Epac2, but not Epac1, was predominantly expressed in the liver. Moreover, 8-CPT inhibited glycogen accumulation and GK translocation and enhanced the mRNA expression of gluconeogenic enzymes. ESI-05 failed to reverse glucagon-induced suppression of glycogen storage and partially inhibited glucagon-induced GK translocation and the mRNA expression of gluconeogenic enzymes. CONCLUSIONS Epac signaling plays a role in mediating the glucogenic action of glucagon in the hepatocytes.
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Affiliation(s)
- Yusuke Shiozaki‐Takagi
- Research Center of Health, Physical Fitness and SportsNagoya UniversityNagoyaJapan
- Department of Pathobiochemistry, Faculty of PharmacyMeijo UniversityNagoyaJapan
- Present address:
Division of Cell Signaling and Molecular Medicine, Institute of Medical ScienceThe University of TokyoTokyoJapan
| | - Nobuaki Ozaki
- Research Center of Health, Physical Fitness and SportsNagoya UniversityNagoyaJapan
- Division of EndocrinologyJapanese Red Cross Aichi Medical Center Nagoya Daiichi HospitalNagoyaJapan
| | - Yukiyasu Toyoda
- Department of Pathobiochemistry, Faculty of PharmacyMeijo UniversityNagoyaJapan
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Beamish CA, Lee YK, Gaber AO, Chanana P, Graviss EA, Kloc M, Gaber MW, Hsueh WA, Sabek OM. Osteocalcin protects islet identity in low-density lipoprotein receptor knockout mice on high-fat diet. J Endocrinol 2024; 261:e230352. [PMID: 38305305 DOI: 10.1530/joe-23-0352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 02/02/2024] [Indexed: 02/03/2024]
Abstract
Metabolic syndrome (MetS) is an increasing global health threat and strong risk factor for type 2 diabetes (T2D). MetS causes both hyperinsulinemia and islet size overexpansion, and pancreatic β-cell failure impacts insulin and proinsulin secretion, mitochondrial density, and cellular identity loss. The low-density lipoprotein receptor knockout (LDLr-/-) model combined with high-fat diet (HFD) has been used to study alterations in multiple organs, but little is known about the changes to β-cell identity resulting from MetS. Osteocalcin (OC), an insulin-sensitizing protein secreted by bone, shows promising impact on β-cell identity and function. LDLr-/- mice at 12 months were fed chow or HFD for 3 months ± 4.5 ng/h OC. Islets were examined by immunofluorescence for alterations in nuclear Nkx6.1 and PDX1 presence, insulin-glucagon colocalization, islet size and %β-cell and islet area by insulin and synaptophysin, and mitochondria fluorescence intensity by Tomm20. Bone mineral density (BMD) and %fat changes were examined by Piximus Dexa scanning. HFD-fed mice showed fasting hyperglycemia by 15 months, increased weight gain, %fat, and fasting serum insulin and proinsulin; concurrent OC treatment mitigated weight increase and showed lower proinsulin-to-insulin ratio, and higher BMD. HFD increased %β and %islet area, while simultaneous OC-treatment with HFD was comparable to chow-fed mice. Significant reductions in nuclear PDX1 and Nkx6.1 expression, increased insulin-glucagon colocalization, and reduction in β-cell mitochondria fluorescence intensity were noted with HFD, but largely prevented with OC administration. OC supplementation here suggests a benefit to β-cell identity in LDLr-/- mice and offers intriguing clinical implications for countering metabolic syndrome.
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Affiliation(s)
- Christine A Beamish
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
| | - Yoon K Lee
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
| | - A Osama Gaber
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
| | - Priyanka Chanana
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
| | - Edward A Graviss
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Pathology and Genomic Medicine, Houston Methodist Research Institute, Houston, Texas, USA
| | - Malgorzata Kloc
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Cell and Microbiology, Weill Cornell Medical College, New York, New York, USA
- Department of Genetics, The University of Texas Anderson Cancer Center, Houston, Texas, USA
| | - M Waleed Gaber
- Department of Pediatrics, Hematology-Oncology Section, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, Texas, USA
| | - Willa A Hsueh
- Department of Internal Medicine, The Ohio State University Diabetes and Metabolism Research Center, Columbus, Ohio, USA
| | - Omaima M Sabek
- Department of Surgery, Houston Methodist Research Institute, Houston, Texas, USA
- Department of Cell and Microbiology, Weill Cornell Medical College, New York, New York, USA
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Fang H, Li Q, Wang H, Ren Y, Zhang L, Yang L. Maternal nutrient metabolism in the liver during pregnancy. Front Endocrinol (Lausanne) 2024; 15:1295677. [PMID: 38572473 PMCID: PMC10987773 DOI: 10.3389/fendo.2024.1295677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 03/08/2024] [Indexed: 04/05/2024] Open
Abstract
The liver plays pivotal roles in nutrient metabolism, and correct hepatic adaptations are required in maternal nutrient metabolism during pregnancy. In this review, hepatic nutrient metabolism, including glucose metabolism, lipid and cholesterol metabolism, and protein and amino acid metabolism, is first addressed. In addition, recent progress on maternal hepatic adaptations in nutrient metabolism during pregnancy is discussed. Finally, the factors that regulate hepatic nutrient metabolism during pregnancy are highlighted, and the factors include follicle-stimulating hormone, estrogen, progesterone, insulin-like growth factor 1, prostaglandins fibroblast growth factor 21, serotonin, growth hormone, adrenocorticotropic hormone, prolactin, thyroid stimulating hormone, melatonin, adrenal hormone, leptin, glucagon-like peptide-1, insulin glucagon and thyroid hormone. Our vision is that more attention should be paid to liver nutrient metabolism during pregnancy, which will be helpful for utilizing nutrient appropriately and efficiently, and avoiding liver diseases during pregnancy.
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Affiliation(s)
- Hongxu Fang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, Handan, China
| | - Qingyang Li
- College of Life Sciences, Hebei Normal University, Shijiazhuang, China
| | - Haichao Wang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, Handan, China
| | - Ying Ren
- School of Life Sciences and Food Engineering, Hebei University of Engineering, Handan, China
| | - Leying Zhang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, Handan, China
| | - Ling Yang
- School of Life Sciences and Food Engineering, Hebei University of Engineering, Handan, China
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Zilstorff DB, Richter MM, Hannibal J, Jørgensen HL, Sennels HP, Wewer Albrechtsen NJ. Secretion of glucagon, GLP-1 and GIP may be affected by circadian rhythm in healthy males. BMC Endocr Disord 2024; 24:38. [PMID: 38481208 PMCID: PMC10938734 DOI: 10.1186/s12902-024-01566-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 03/04/2024] [Indexed: 03/17/2024] Open
Abstract
BACKGROUND Glucagon is secreted from pancreatic alpha cells in response to low blood glucose and increases hepatic glucose production. Furthermore, glucagon enhances hepatic protein and lipid metabolism during a mixed meal. Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are secreted from gut endocrine cells during meals and control glucose homeostasis by potentiating insulin secretion and inhibiting food intake. Both glucose homeostasis and food intake have been reported to be affected by circadian rhythms and vice versa. In this study, we investigated whether the secretion of glucagon, GLP-1 and GIP was affected by circadian rhythms. METHODS A total of 24 healthy men with regular sleep schedules were examined for 24 h at the hospital ward with 15 h of wakefulness and 9 h of sleep. Food intake was standardized, and blood samples were obtained every third hour. Plasma concentrations of glucagon, GLP-1 and GIP were measured, and data were analyzed by rhythmometric statistical methods. Available data on plasma glucose and plasma C-peptide were also included. RESULTS Plasma concentrations of glucagon, GLP-1, GIP, C-peptide and glucose fluctuated with a diurnal 24-h rhythm, with the highest levels during the day and the lowest levels during the night: glucagon (p < 0.0001, peak time 18:26 h), GLP-1 (p < 0.0001, peak time 17:28 h), GIP (p < 0.0001, peak time 18:01 h), C-peptide (p < 0.0001, peak time 17.59 h), and glucose (p < 0.0001, peak time 23:26 h). As expected, we found significant correlations between plasma concentrations of C-peptide and GLP-1 and GIP but did not find correlations between glucose concentrations and concentrations of glucagon, GLP-1 and GIP. CONCLUSIONS Our results demonstrate that under meal conditions that are similar to that of many free-living individuals, plasma concentrations of glucagon, GLP-1 and GIP were observed to be higher during daytime and evening than overnight. These findings underpin disturbed circadian rhythm as a potential risk factor for diabetes and obesity. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT06166368. Registered 12 December 2023.
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Affiliation(s)
- Dorte B Zilstorff
- Department of Clinical Biochemistry, Copenhagen University Hospital - Bispebjerg Hospital, Copenhagen, Denmark
| | - Michael M Richter
- Department of Clinical Biochemistry, Copenhagen University Hospital - Bispebjerg Hospital, Copenhagen, Denmark
- NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens Hannibal
- Department of Clinical Biochemistry, Copenhagen University Hospital - Bispebjerg Hospital, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Henrik L Jørgensen
- Department of Clinical Biochemistry, Copenhagen University Hospital - Hvidovre, Hvidovre, Denmark
| | - Henriette P Sennels
- Department of Clinical Biochemistry, Copenhagen University Hospital - Bispebjerg Hospital, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Clinical Biochemistry, Copenhagen University Hospital - Bispebjerg Hospital, Copenhagen, Denmark.
- NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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10
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Estes SK, Shiota C, O'Brien TP, Printz RL, Shiota M. The impact of glucagon to support postabsorptive glucose flux and glycemia in healthy rats and its attenuation in male Zucker diabetic fatty rats. Am J Physiol Endocrinol Metab 2024; 326:E308-E325. [PMID: 38265288 DOI: 10.1152/ajpendo.00192.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 01/19/2024] [Accepted: 01/19/2024] [Indexed: 01/25/2024]
Abstract
Hyperglucagonemia is a hallmark of type 2 diabetes (T2DM), yet the role of elevated plasma glucagon (P-GCG) to promote excessive postabsorptive glucose production and contribute to hyperglycemia in patients with this disease remains debatable. We investigated the acute action of P-GCG to safeguard/support postabsorptive endogenous glucose production (EGP) and euglycemia in healthy Zucker control lean (ZCL) rats. Using male Zucker diabetic fatty (ZDF) rats that exhibit the typical metabolic disorders of human T2DM, such as excessive EGP, hyperglycemia, hyperinsulinemia, and hyperglucagonemia, we examined the ability of hyperglucagonemia to promote greater rates of postabsorptive EGP and hyperglycemia. Euglycemic or hyperglycemic basal insulin (INS-BC) and glucagon (GCG-BC) clamps were performed in the absence or during an acute setting of glucagon deficiency (GCG-DF, ∼10% of basal), either alone or in combination with insulin deficiency (INS-DF, ∼10% of basal). Glucose appearance, disappearance, and cycling rates were measured using [2-3H] and [3-3H]-glucose. In ZCL rats, GCG-DF reduced the levels of hepatic cyclic AMP, EGP, and plasma glucose (PG) by 50%, 32%, and 50%, respectively. EGP fell in the presence GCG-DF and INS-BC, but under GCG-DF and INS-DF, EGP and PG increased two- and threefold, respectively. GCG-DF revealed the hyperglucagonemia present in ZDF rats lacked the ability to regulate hepatic intracellular cyclic AMP levels and glucose flux, since EGP and PG levels fell by only 10%. We conclude that the liver in T2DM suffers from resistance to all three major regulatory factors, glucagon, insulin, and glucose, thus leading to a loss of metabolic flexibility.NEW & NOTEWORTHY In postabsorptive state, basal plasma insulin (P-INS) and plasma glucose (PG) act dominantly to increase hepatic glucose cycling and reduce endogenous glucose production (EGP) and PG in healthy rats, which is only counteracted by the acute action of basal plasma glucagon (P-GCG) to support EGP and euglycemia. Hyperglucagonemia, a hallmark of type 2 diabetes (T2DM) present in Zucker diabetic fatty (ZDF) rats, is not the primary mediator of hyperglycemia and high EGP as commonly thought; instead, the liver is resistant to glucagon as well as insulin and glucose.
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Affiliation(s)
- Shanea K Estes
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Chiyo Shiota
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Tracy P O'Brien
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Richard L Printz
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Masakazu Shiota
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
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11
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Gray SM, Goonatilleke E, Emrick MA, Becker JO, Hoofnagle AN, Stefanovski D, He W, Zhang G, Tong J, Campbell J, D'Alessio DA. High Doses of Exogenous Glucagon Stimulate Insulin Secretion and Reduce Insulin Clearance in Healthy Humans. Diabetes 2024; 73:412-425. [PMID: 38015721 PMCID: PMC10882148 DOI: 10.2337/db23-0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 11/20/2023] [Indexed: 11/30/2023]
Abstract
Glucagon is generally defined as a counterregulatory hormone with a primary role to raise blood glucose concentrations by increasing endogenous glucose production (EGP) in response to hypoglycemia. However, glucagon has long been known to stimulate insulin release, and recent preclinical findings have supported a paracrine action of glucagon directly on islet β-cells that augments their secretion. In mice, the insulinotropic effect of glucagon is glucose dependent and not present during basal euglycemia. To test the hypothesis that the relative effects of glucagon on hepatic and islet function also vary with blood glucose, a group of healthy subjects received glucagon (100 ng/kg) during fasting glycemia or experimental hyperglycemia (∼150 mg/dL) on 2 separate days. During fasting euglycemia, administration of glucagon caused blood glucose to rise due to increased EGP, with a delayed increase of insulin secretion. When given during experimental hyperglycemia, glucagon caused a rapid, threefold increase in insulin secretion, as well as a more gradual increase in EGP. Under both conditions, insulin clearance was decreased in response to glucagon infusion. The insulinotropic action of glucagon, which is proportional to the degree of blood glucose elevation, suggests distinct physiologic roles in the fasting and prandial states. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Sarah M Gray
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Elisha Goonatilleke
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Michelle A Emrick
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Jessica O Becker
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
| | - Andrew N Hoofnagle
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA
| | - Darko Stefanovski
- Department of Clinical Studies-New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square
| | - Wentao He
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Guofang Zhang
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Jenny Tong
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA
- Endocrine Section, VA Puget Sound Health Care System, Seattle
| | - Jonathan Campbell
- Duke Molecular Physiology Institute, Duke University, Durham, NC
- Division of Endocrinology, Department of Medicine, Duke University, Durham, NC
| | - David A D'Alessio
- Duke Molecular Physiology Institute, Duke University, Durham, NC
- Division of Endocrinology, Department of Medicine, Duke University, Durham, NC
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12
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Coykendall VMN, Qian MF, Tellez K, Bautista A, Bevacqua RJ, Gu X, Hang Y, Neukam M, Zhao W, Chang C, MacDonald PE, Kim SK. RFX6 Maintains Gene Expression and Function of Adult Human Islet α-Cells. Diabetes 2024; 73:448-460. [PMID: 38064570 PMCID: PMC10882151 DOI: 10.2337/db23-0483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 11/21/2023] [Indexed: 02/22/2024]
Abstract
Mutations in the gene encoding the transcription factor regulatory factor X-box binding 6 (RFX6) are associated with human diabetes. Within pancreatic islets, RFX6 expression is most abundant in islet α-cells, and α-cell RFX6 expression is altered in diabetes. However, the roles of RFX6 in regulating gene expression, glucagon output, and other crucial human adult α-cell functions are not yet understood. We developed a method for selective genetic targeting of human α-cells and assessed RFX6-dependent α-cell function. RFX6 suppression with RNA interference led to impaired α-cell exocytosis and dysregulated glucagon secretion in vitro and in vivo. By contrast, these phenotypes were not observed with RFX6 suppression across all islet cells. Transcriptomics in α-cells revealed RFX6-dependent expression of genes governing nutrient sensing, hormone processing, and secretion, with some of these exclusively expressed in human α-cells. Mapping of RFX6 DNA-binding sites in primary human islet cells identified a subset of direct RFX6 target genes. Together, these data unveil RFX6-dependent genetic targets and mechanisms crucial for regulating adult human α-cell function. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Vy M N Coykendall
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Mollie F Qian
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Krissie Tellez
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Austin Bautista
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Romina J Bevacqua
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Xueying Gu
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Yan Hang
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, CA
| | - Martin Neukam
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Weichen Zhao
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Charles Chang
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
| | - Patrick E MacDonald
- Department of Pharmacology and Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Seung K Kim
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA
- Stanford Diabetes Research Center, Stanford University School of Medicine, Stanford, CA
- Department of Medicine, Stanford University School of Medicine, Stanford, CA
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA
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13
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Goodarzi N, Bashiri A. Histology and immunofluorescent study of the pancreas in lovebird (Agapornis personatus). Vet Med Sci 2024; 10:e1394. [PMID: 38459816 PMCID: PMC10924273 DOI: 10.1002/vms3.1394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2024] Open
Abstract
BACKGROUND Lovebird (Agapornis personatus) is a monotypic species of bird of the lovebird genus in the parrot family Psittaculidae and order Psittaciformes. OBJECTIVES The present study was designed to investigate the histology and immunohistochemistry of the pancreas in the lovebird. METHODS Totally, three adult birds were used. The pancreas was assessed using histological and immunofluorescent staining to detect insulin, glucagon, somatostatin, pancreatic polypeptide (PP) and neuropeptide Y (NY). RESULTS The exocrine pancreas was composed of pyramidal acinar cells with zymogen granules at the apical cytoplasm. The endocrine pancreas was identified as large alpha, small beta and mixed islets of Langerhans. No intercalated duct was observed. Alpha cells with a density of 28.55% were the most numerous cell type, which were populated throughout the large islets, especially at the periphery. The beta cells with a density of 15.78% were accumulated mostly at the periphery of islets. The delta cells exhibited 17.81% intensity. Despite their lower density, the distribution of delta cells was like that of A cells throughout the islets. PP and NY cells were distinguished with densities of 14.69% and 20.63%, respectively. CONCLUSIONS Although the arrangement of acinar cells, ductal systems and endocrine islets reflects patterns observed in various avian species, the absence of intercalated duct, the presence of three types of Langerhans islets as alpha, beta and mixed islets and the high expression of NY in the islets were some unique features observed in the current study. These findings contribute to the broader understanding of avian pancreas histology.
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Affiliation(s)
- Nader Goodarzi
- Department of Basic Sciences and Pathobiology, Faculty of Veterinary MedicineRazi UniversityKermanshahIran
| | - Ayda Bashiri
- Faculty of Veterinary Medicine, Islamic Azad UniversitySanandaj BranchSanandajIran
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14
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Spezani R, Marinho TS, Reis TS, Aguila MB, Mandarim-de-Lacerda CA. Cotadutide (GLP-1/Glucagon dual receptor agonist) modulates hypothalamic orexigenic and anorexigenic neuropeptides in obese mice. Peptides 2024; 173:171138. [PMID: 38147963 DOI: 10.1016/j.peptides.2023.171138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/15/2023] [Accepted: 12/18/2023] [Indexed: 12/28/2023]
Abstract
The hypothalamic neuropeptides linked to appetite and satiety were investigated in obese mice treated with cotadutide (a dual receptor agonist of glucagon-like peptide 1 (GLP-1R)/Glucagon (GCGR)). Twelve-week-old male C57BL/6 mice were fed a control diet (C group, n = 20) or a high-fat diet (HF group, n = 20) for ten weeks. Each group was further divided, adding cotadutide treatment and forming groups C, CC, HF, and HFC for four additional weeks. The hypothalamic arcuate neurons were labeled by immunofluorescence, and protein expressions (Western blotting) for neuropeptide Y (NPY), proopiomelanocortin (POMC), agouti-related protein (AgRP), and cocaine- and amphetamine-regulated transcript (CART). Cotadutide enhanced POMC and CART neuropeptides and depressed NPY and AGRP neuropeptides. In addition, gene expressions (RT-qPCR) determined that Lepr (leptin receptor) and Calcr (calcitonin receptor) were diminished in HF compared to C but enhanced in CC compared to C and HFC compared to HF. Besides, Socs3 (suppressor of cytokine signaling 3) was decreased in HFC compared to HF, while Sst (somatostatin) was higher in HFC compared to HF; Tac1 (tachykinin 1) and Mc4r (melanocortin-4-receptor) were lower in HF compared to C but increased in HFC compared to HF. Also, Glp1r and Gcgr were higher in HFC compared to HF. In conclusion, the findings are compelling, demonstrating the effects of cotadutide on hypothalamic neuropeptides and hormone receptors of obese mice. Cotadutide modulates energy balance through the gut-brain axis and its associated signaling pathways. The study provides insights into the mechanisms underlying cotadutide's anti-obesity effects and its possible implications for obesity treatment.
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Affiliation(s)
- Renata Spezani
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Institute of Biology, Biomedical Center, The University of the State of Rio de Janeiro, Brazil
| | - Thatiany Souza Marinho
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Institute of Biology, Biomedical Center, The University of the State of Rio de Janeiro, Brazil
| | - Thiago Santos Reis
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Institute of Biology, Biomedical Center, The University of the State of Rio de Janeiro, Brazil
| | - Marcia Barbosa Aguila
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Institute of Biology, Biomedical Center, The University of the State of Rio de Janeiro, Brazil
| | - Carlos A Mandarim-de-Lacerda
- Laboratory of Morphometry, Metabolism, and Cardiovascular Disease, Institute of Biology, Biomedical Center, The University of the State of Rio de Janeiro, Brazil.
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15
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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Shankar K, Ramborger J, Bonnet-Zahedi S, Carrette LLG, George O. Acute nicotine intake increases feeding behavior through decreasing glucagon signaling in dependent male and female rats. Horm Behav 2024; 159:105447. [PMID: 37926623 DOI: 10.1016/j.yhbeh.2023.105447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 09/26/2023] [Accepted: 10/20/2023] [Indexed: 11/07/2023]
Abstract
Chronic use of nicotine is known to dysregulate metabolic signaling through altering circulating levels of feeding-related hormones, contributing to the onset of disorders like type 2 diabetes. However, little is known about the acute effects of nicotine on hormonal signaling. We previously identified an acute increase in food intake following acute nicotine, and we sought to determine whether this behavior was due to a change in hormone levels. We first identified that acute nicotine injection produces an increase in feeding behavior in dependent rats, but not nondependent rats. We confirmed that chronic nicotine use increases circulating levels of insulin, leptin, and ghrelin, and these correlate with rats' body weight and food intake. Acute nicotine injection in dependent animals decreased circulating GLP-1 and glucagon levels, and administration of glucagon prior to acute nicotine injection prevented the acute increase in feeding behavior. Thus, acute nicotine injection increases feeding behavior in dependent rats by decreasing glucagon signaling.
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Affiliation(s)
- Kokila Shankar
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA; The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jarryd Ramborger
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA
| | - Sélène Bonnet-Zahedi
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA; Institut de Neurosciences de la Timone, Aix-Marseille Université, Marseille 13005, France
| | - Lieselot L G Carrette
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA
| | - Olivier George
- Department of Psychiatry, University of California San Diego, La Jolla, CA 92093, USA.
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17
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Aglan HA, Kotob SE, Mahmoud NS, Kishta MS, Ahmed HH. Bone marrow stem cell-derived β-cells: New issue for diabetes cell therapy. Tissue Cell 2024; 86:102280. [PMID: 38029457 DOI: 10.1016/j.tice.2023.102280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/19/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023]
Abstract
This investigation aimed to establish the promising role of insulin-producing cells (IPCs) growing from bone marrow-mesenchymal stem cells (BM-MSCs) in relieving hyperglycemia induced in rats. BM-MSCs were differentiated into IPCs using three different protocols. The efficiency of BM-MSCs differentiation into IPCs in vitro was confirmed by detecting IPCs specific gene expression (Foxa-2, PDX-1 and Ngn-3) and insulin release assay. The in vivo study design included 3 groups of male Wistar rats; negative control group, diabetic group and IPCs-transfused group (5 ×106 cells of the most functional IPCs/rat). One month after IPCs infusion, serum glucose, insulin, c-peptide and visfatin levels as well as pancreatic glucagon level were quantified. Gene expression analysis of pancreatic Foxa-2 and Sox-17, IGF-1 and FGF-10 was done. Additionally, histological investigation of pancreatic tissue sections was performed. Our data clarified that, the most functional IPCs are those generated from BM-MSCs using differentiation protocol 3 as indicated by the significant up-regulation of Foxa-2, PDX-1 and Ngn-3 gene expression levels. These findings were further emphasized by releasing of a significant amount of insulin in response to glucose load. The transplantation of the IPCs in diabetic rats elicited significant decline in serum glucose, visfatin and pancreatic glucagon levels along with significant rise in serum insulin and c-peptide levels. Moreover, it triggered significant up-regulation in the expression levels of pancreatic Foxa-2, Sox-17, IGF-1 and FGF-10 genes versus the untreated diabetic counterpart. The histopathological examination of pancreatic tissue almost assisted the biochemical and molecular genetic analyses. These results disclose that the cell therapy holds potential to develop a new cure for DM based on the capability of BM-MSCs to generate β-cell phenotype using specific protocol.
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Affiliation(s)
- Hadeer A Aglan
- Hormones Department, Medical Research and Clinical Studies Institute, National Research Centre, Dokki, Giza, Egypt; Stem Cell Lab., Center of Excellence for Advanced Sciences, National Research Centre, Dokki, Giza, Egypt.
| | - Soheir E Kotob
- Hormones Department, Medical Research and Clinical Studies Institute, National Research Centre, Dokki, Giza, Egypt
| | - Nadia S Mahmoud
- Hormones Department, Medical Research and Clinical Studies Institute, National Research Centre, Dokki, Giza, Egypt; Stem Cell Lab., Center of Excellence for Advanced Sciences, National Research Centre, Dokki, Giza, Egypt
| | - Mohamed S Kishta
- Hormones Department, Medical Research and Clinical Studies Institute, National Research Centre, Dokki, Giza, Egypt; Stem Cell Lab., Center of Excellence for Advanced Sciences, National Research Centre, Dokki, Giza, Egypt
| | - Hanaa H Ahmed
- Hormones Department, Medical Research and Clinical Studies Institute, National Research Centre, Dokki, Giza, Egypt; Stem Cell Lab., Center of Excellence for Advanced Sciences, National Research Centre, Dokki, Giza, Egypt
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18
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Xia S, Xi F, Ou K, Zhang Y, Ni H, Wang C, Wang Q. The effects of EGCG supplementation on pancreatic islet α and β cells distribution in adult male mice. J Nutr Biochem 2024; 124:109529. [PMID: 37951555 DOI: 10.1016/j.jnutbio.2023.109529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 10/23/2023] [Accepted: 11/08/2023] [Indexed: 11/14/2023]
Abstract
Tea and tea products are widely used as the most popular beverage in the world. EGCG is the most abundant bioactive tea polyphenol in green tea, which has positive effects on the prevention and treatment of diabetes. However, the impact of EGCG exposure on glucose homeostasis and islets in adult mice have not been reported. In this study, we studied glucose homeostasis and the morphological and molecular changes of pancreatic islet α and β cells in adult male mice after 60 d of exposure to 1 and 10 mg/kg/day EGCG by drinking water. Glucose homeostasis was not affected in both EGCG groups. The expression of pancreatic duodenal homebox1 (Pdx1) in β cells was upregulated, which might be related to increased insulin level, β cell mass and β cell proliferation in 10 mg/kg/day EGCG group. The expression of aristaless-related homeobox (Arx) in α cells did not change significantly, which corresponded with the unchanged α-cell mass. The significant reduction of musculoaponeurotic fibrosarcoma oncogene homolog B (MafB) positive α-cells might be associated with decreased glucagon level in both EGCG groups. These results suggest that EGCG supplementation dose-dependent increases β cell mass of adult mice and affects the levels of serum insulin and glucagon. Our results show that regular tea drinking in healthy people may have the possibility of preventing diabetes.
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Affiliation(s)
- Siyu Xia
- School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Feifei Xi
- School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Kunlin Ou
- School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Ying Zhang
- School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Huizhen Ni
- School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Chonggang Wang
- School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Qin Wang
- School of Life Sciences, Xiamen University, Xiamen, PR China.
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19
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Castillo-Armengol J, Marzetta F, Rodriguez Sanchez-Archidona A, Fledelius C, Evans M, McNeilly A, McCrimmon RJ, Ibberson M, Thorens B. Disrupted hypothalamic transcriptomics and proteomics in a mouse model of type 2 diabetes exposed to recurrent hypoglycaemia. Diabetologia 2024; 67:371-391. [PMID: 38017352 PMCID: PMC10789691 DOI: 10.1007/s00125-023-06043-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 09/07/2023] [Indexed: 11/30/2023]
Abstract
AIMS/HYPOTHESIS Repeated exposures to insulin-induced hypoglycaemia in people with diabetes progressively impairs the counterregulatory response (CRR) that restores normoglycaemia. This defect is characterised by reduced secretion of glucagon and other counterregulatory hormones. Evidence indicates that glucose-responsive neurons located in the hypothalamus orchestrate the CRR. Here, we aimed to identify the changes in hypothalamic gene and protein expression that underlie impaired CRR in a mouse model of defective CRR. METHODS High-fat-diet fed and low-dose streptozocin-treated C57BL/6N mice were exposed to one (acute hypoglycaemia [AH]) or multiple (recurrent hypoglycaemia [RH]) insulin-induced hypoglycaemic episodes and plasma glucagon levels were measured. Single-nuclei RNA-seq (snRNA-seq) data were obtained from the hypothalamus and cortex of mice exposed to AH and RH. Proteomic data were obtained from hypothalamic synaptosomal fractions. RESULTS The final insulin injection resulted in similar plasma glucose levels in the RH group and AH groups, but glucagon secretion was significantly lower in the RH group (AH: 94.5±9.2 ng/l [n=33]; RH: 59.0±4.8 ng/l [n=37]; p<0.001). Analysis of snRNA-seq data revealed similar proportions of hypothalamic cell subpopulations in the AH- and RH-exposed mice. Changes in transcriptional profiles were found in all cell types analysed. In neurons from RH-exposed mice, we observed a significant decrease in expression of Avp, Pmch and Pcsk1n, and the most overexpressed gene was Kcnq1ot1, as compared with AH-exposed mice. Gene ontology analysis of differentially expressed genes (DEGs) indicated a coordinated decrease in many oxidative phosphorylation genes and reduced expression of vacuolar H+- and Na+/K+-ATPases; these observations were in large part confirmed in the proteomic analysis of synaptosomal fractions. Compared with AH-exposed mice, oligodendrocytes from RH-exposed mice had major changes in gene expression that suggested reduced myelin formation. In astrocytes from RH-exposed mice, DEGs indicated reduced capacity for neurotransmitters scavenging in tripartite synapses as compared with astrocytes from AH-exposed mice. In addition, in neurons and astrocytes, multiple changes in gene expression suggested increased amyloid beta (Aβ) production and stability. The snRNA-seq analysis of the cortex showed that the adaptation to RH involved different biological processes from those seen in the hypothalamus. CONCLUSIONS/INTERPRETATION The present study provides a model of defective counterregulation in a mouse model of type 2 diabetes. It shows that repeated hypoglycaemic episodes induce multiple defects affecting all hypothalamic cell types and their interactions, indicative of impaired neuronal network signalling and dysegulated hypoglycaemia sensing, and displaying features of neurodegenerative diseases. It also shows that repeated hypoglycaemia leads to specific molecular adaptation in the hypothalamus when compared with the cortex. DATA AVAILABILITY The transcriptomic dataset is available via the GEO ( http://www.ncbi.nlm.nih.gov/geo/ ), using the accession no. GSE226277. The proteomic dataset is available via the ProteomeXchange data repository ( http://www.proteomexchange.org ), using the accession no. PXD040183.
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Affiliation(s)
- Judit Castillo-Armengol
- Novo Nordisk A/S, Måløv, Denmark
- Center for Integrative Genomics (CIG), University of Lausanne, Lausanne, Switzerland
| | - Flavia Marzetta
- Vital-IT Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | | | | | - Mark Evans
- IMS Metabolic Research Laboratories, Addenbrookes Biomedical Campus, Cambridge, UK
| | | | | | - Mark Ibberson
- Vital-IT Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Bernard Thorens
- Center for Integrative Genomics (CIG), University of Lausanne, Lausanne, Switzerland.
- Vital-IT Group, SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.
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20
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Vázquez Torres S, Leung PJY, Venkatesh P, Lutz ID, Hink F, Huynh HH, Becker J, Yeh AHW, Juergens D, Bennett NR, Hoofnagle AN, Huang E, MacCoss MJ, Expòsit M, Lee GR, Bera AK, Kang A, De La Cruz J, Levine PM, Li X, Lamb M, Gerben SR, Murray A, Heine P, Korkmaz EN, Nivala J, Stewart L, Watson JL, Rogers JM, Baker D. De novo design of high-affinity binders of bioactive helical peptides. Nature 2024; 626:435-442. [PMID: 38109936 PMCID: PMC10849960 DOI: 10.1038/s41586-023-06953-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 12/07/2023] [Indexed: 12/20/2023]
Abstract
Many peptide hormones form an α-helix on binding their receptors1-4, and sensitive methods for their detection could contribute to better clinical management of disease5. De novo protein design can now generate binders with high affinity and specificity to structured proteins6,7. However, the design of interactions between proteins and short peptides with helical propensity is an unmet challenge. Here we describe parametric generation and deep learning-based methods for designing proteins to address this challenge. We show that by extending RFdiffusion8 to enable binder design to flexible targets, and to refining input structure models by successive noising and denoising (partial diffusion), picomolar-affinity binders can be generated to helical peptide targets by either refining designs generated with other methods, or completely de novo starting from random noise distributions without any subsequent experimental optimization. The RFdiffusion designs enable the enrichment and subsequent detection of parathyroid hormone and glucagon by mass spectrometry, and the construction of bioluminescence-based protein biosensors. The ability to design binders to conformationally variable targets, and to optimize by partial diffusion both natural and designed proteins, should be broadly useful.
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Affiliation(s)
- Susana Vázquez Torres
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Graduate Program in Biological Physics, Structure and Design, University of Washington, Seattle, WA, USA
| | - Philip J Y Leung
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Graduate Program in Molecular Engineering, University of Washington, Seattle, WA, USA
| | - Preetham Venkatesh
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Graduate Program in Biological Physics, Structure and Design, University of Washington, Seattle, WA, USA
| | - Isaac D Lutz
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Fabian Hink
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Huu-Hien Huynh
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Jessica Becker
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Andy Hsien-Wei Yeh
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - David Juergens
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Graduate Program in Molecular Engineering, University of Washington, Seattle, WA, USA
| | - Nathaniel R Bennett
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Graduate Program in Molecular Engineering, University of Washington, Seattle, WA, USA
| | - Andrew N Hoofnagle
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Eric Huang
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Marc Expòsit
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Graduate Program in Molecular Engineering, University of Washington, Seattle, WA, USA
| | - Gyu Rie Lee
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Asim K Bera
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Alex Kang
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Joshmyn De La Cruz
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Paul M Levine
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Xinting Li
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Mila Lamb
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Stacey R Gerben
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Analisa Murray
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Piper Heine
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Elif Nihal Korkmaz
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Jeff Nivala
- School of Computer Science and Engineering, University of Washington, Seattle, WA, USA
- Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA, USA
| | - Lance Stewart
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Joseph L Watson
- Department of Biochemistry, University of Washington, Seattle, WA, USA.
- Institute for Protein Design, University of Washington, Seattle, WA, USA.
| | - Joseph M Rogers
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA, USA.
- Institute for Protein Design, University of Washington, Seattle, WA, USA.
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA.
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21
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Mohsin S, Elabadlah H, Alotaiba MK, AlAmry S, Almehairbi SJ, Harara MMK, Almuhsin AMH, Tariq S, Howarth FC, Adeghate EA. High-Density Lipoprotein Is Located Alongside Insulin in the Islets of Langerhans of Normal and Rodent Models of Diabetes. Nutrients 2024; 16:313. [PMID: 38276551 PMCID: PMC10818677 DOI: 10.3390/nu16020313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 01/10/2024] [Accepted: 01/16/2024] [Indexed: 01/27/2024] Open
Abstract
Recent studies have implicated pre-beta and beta lipoproteins (VLDL and LDL) in the etiopathogenesis of complications of diabetes mellitus (DM). In contrast, alpha lipoprotein (HDL) is protective of the beta cells of the pancreas. This study examined the distribution of HDL in the islets of Langerhans of murine models of type 1 diabetic rats (streptozotocin (STZ)-induced DM in Wistar rats) and type 2 models of DM rats (Goto-Kakizaki (GK), non-diabetic Zucker lean (ZL), and Zucker diabetic and fatty (ZDF)). The extent by which HDL co-localizes with insulin or glucagon in the islets of the pancreas was also investigated. Pancreatic tissues of Wistar non-diabetic, diabetic Wistar, GK, ZL, and ZDF rats were processed for immunohistochemistry. Pancreatic samples of GK rats fed with either a low-fat or a high-fat diet were prepared for transmission immune-electron microscopy (TIEM) to establish the cytoplasmic localization of HDL in islet cells. HDL was detected in the core and periphery of pancreatic islets of Wistar non-diabetic and diabetic, GK, ZL, and ZDF rats. The average total of islet cells immune positive for HDL was markedly (<0.05) reduced in GK and ZDF rats in comparison to Wistar controls. The number of islet cells containing HDL was also remarkably (p < 0.05) reduced in Wistar diabetic rats and GK models fed on high-fat food. The co-localization study using immunofluorescence and TIEM techniques showed that HDL is detected alongside insulin within the secretory granules of β-cells. HDL did not co-localize with glucagon. This observation implies that HDL may contribute to the metabolism of insulin.
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Affiliation(s)
- Sahar Mohsin
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Haba Elabadlah
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
- Cambridge Medical and Rehabilitation Center, Al Ain P.O. Box 222297, United Arab Emirates
| | - Mariam K. Alotaiba
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Suhail AlAmry
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Shamma J. Almehairbi
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Maha M. K. Harara
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Aisha M. H. Almuhsin
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Saeed Tariq
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
| | - Frank Christopher Howarth
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates;
| | - Ernest A. Adeghate
- Department of Anatomy, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates; (S.M.)
- Zayed Centre for Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
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22
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Ramzy A, Saber N, Bruin JE, Thompson DM, Kim PTW, Warnock GL, Kieffer TJ. Thyroid Hormone Levels Correlate With the Maturation of Implanted Pancreatic Endoderm Cells in Patients With Type 1 Diabetes. J Clin Endocrinol Metab 2024; 109:413-423. [PMID: 37671625 PMCID: PMC10795919 DOI: 10.1210/clinem/dgad499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 08/09/2023] [Accepted: 08/22/2023] [Indexed: 09/07/2023]
Abstract
BACKGROUND Macroencapsulated pancreatic endoderm cells (PECs) can reverse diabetes in rodents and preclinical studies revealed that thyroid hormones in vitro and in vivo bias PECs to differentiate into insulin-producing cells. In an ongoing clinical trial, PECs implanted in macroencapsulation devices into patients with type 1 diabetes were safe but yielded heterogeneous outcomes. Though most patients developed meal responsive C-peptide, levels were heterogeneous and explanted grafts had variable numbers of surviving cells with variable distribution of endocrine cells. METHODS We measured circulating triiodothyronine and thyroxine levels in all patients treated at 1 of the 7 sites of the ongoing clinical trial and determined if thyroid hormone levels were associated with the C-peptide or glucagon levels and cell fate of implanted PECs. RESULTS Both triiodothyronine and thyroxine levels were significantly associated with the proportion of cells that adopted an insulin-producing fate with a mature phenotype. Thyroid hormone levels were inversely correlated to circulating glucagon levels after implantation, suggesting that thyroid hormones lead PECs to favor an insulin-producing fate over a glucagon-producing fate. In mice, hyperthyroidism led to more rapid maturation of PECs into insulin-producing cells similar in phenotype to PECs in euthyroid mice. CONCLUSION These data highlight the relevance of thyroid hormones in the context of PEC therapy in patients with type 1 diabetes and suggest that a thyroid hormone adjuvant therapy may optimize cell outcomes in some PEC recipients.
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Affiliation(s)
- Adam Ramzy
- Laboratory of Molecular and Cellular Medicine, Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Nelly Saber
- Laboratory of Molecular and Cellular Medicine, Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Jennifer E Bruin
- Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - David M Thompson
- Division of Endocrinology, Department of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Peter T W Kim
- Department of Surgery, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Garth L Warnock
- Department of Surgery, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Timothy J Kieffer
- Laboratory of Molecular and Cellular Medicine, Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- Department of Surgery, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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23
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Yu JH, Choi MG, Lee NY, Kwon A, Lee E, Koo JH. Hepatocyte GPCR signaling regulates IRF3 to control hepatic stellate cell transdifferentiation. Cell Commun Signal 2024; 22:48. [PMID: 38233853 PMCID: PMC10795343 DOI: 10.1186/s12964-023-01416-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 12/02/2023] [Indexed: 01/19/2024] Open
Abstract
BACKGROUND Interferon Regulatory Factor 3 (IRF3) is a transcription factor that plays a crucial role in the innate immune response by recognizing and responding to foreign antigens. Recently, its roles in sterile conditions are being studied, as in metabolic and fibrotic diseases. However, the search on the upstream regulator for efficient pharmacological targeting is yet to be fully explored. Here, we show that G protein-coupled receptors (GPCRs) can regulate IRF3 phosphorylation through of GPCR-Gα protein interaction. RESULTS IRF3 and target genes were strongly associated with fibrosis markers in liver fibrosis patients and models. Conditioned media from MIHA hepatocytes overexpressing IRF3 induced fibrogenic activation of LX-2 hepatic stellate cells (HSCs). In an overexpression library screening using active mutant Gα subunits and Phos-tag immunoblotting, Gαs was found out to strongly phosphorylate IRF3. Stimulation of Gαs by glucagon or epinephrine or by Gαs-specific designed GPCR phosphorylated IRF3. Protein kinase A (PKA) signaling was primarily responsible for IRF3 phosphorylation and Interleukin 33 (IL-33) expression downstream of Gαs. PKA phosphorylated IRF3 on a previously unrecognized residue and did not require reported upstream kinases such as TANK-binding kinase 1 (TBK1). Activation of Gαs signaling by glucagon induced IL-33 production in hepatocytes. Conditioned media from the hepatocytes activated HSCs, as indicated by α-SMA and COL1A1 expression, and this was reversed by pre-treatment of the media with IL-33 neutralizing antibody. CONCLUSIONS Gαs-coupled GPCR signaling increases IRF3 phosphorylation through cAMP-mediated activation of PKA. This leads to an increase of IL-33 expression, which further contributes to HSC activation. Our findings that hepatocyte GPCR signaling regulates IRF3 to control hepatic stellate cell transdifferentiation provides an insight for understanding the complex intercellular communication during liver fibrosis progression and suggests therapeutic opportunities for the disease. Video Abstract.
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Affiliation(s)
- Jae-Hyun Yu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Myeung Gi Choi
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Na Young Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ari Kwon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Euijin Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ja Hyun Koo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
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24
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Abo SMC, Casella E, Layton AT. Sexual Dimorphism in Substrate Metabolism During Exercise. Bull Math Biol 2024; 86:17. [PMID: 38228814 DOI: 10.1007/s11538-023-01242-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 11/29/2023] [Indexed: 01/18/2024]
Abstract
During aerobic exercise, women oxidize significantly more lipids and less carbohydrates than men. This sexual dimorphism in substrate metabolism has been attributed, in part, to the observed differences in epinephrine and glucagon levels between men and women during exercise. To identify the underpinning candidate physiological mechanisms for these sex differences, we developed a sex-specific multi-scale mathematical model that relates cellular metabolism in the organs to whole-body responses during exercise. We conducted simulations to test the hypothesis that sex differences in the exercise-induced changes to epinephrine and glucagon would result in the sexual dimorphism of hepatic metabolic flux rates via the glucagon-to-insulin ratio (GIR). Indeed, model simulations indicate that the shift towards lipid metabolism in the female model is primarily driven by the liver. The female model liver exhibits resistance to GIR-mediated glycogenolysis, which helps maintain hepatic glycogen levels. This decreases arterial glucose levels and promotes the oxidation of free fatty acids. Furthermore, in the female model, skeletal muscle relies on plasma free fatty acids as the primary fuel source, rather than intramyocellular lipids, whereas the opposite holds true for the male model.
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Affiliation(s)
- Stéphanie M C Abo
- Department of Applied Mathematics, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada.
| | - Elisa Casella
- Department of Applied Mathematics, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada
| | - Anita T Layton
- Department of Applied Mathematics, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada
- Cheriton School of Computer Science, Department of Biology, and School of Pharmacy, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada
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25
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Panzer JK, Caicedo A. A bright future for glucagon and alpha cell biology. J Endocrinol 2024; 260:e220315. [PMID: 37888975 DOI: 10.1530/joe-22-0315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 10/27/2023] [Indexed: 10/28/2023]
Abstract
Long lagging behind insulin, glucagon research has caught up in large part, thanks to technological breakthroughs. Here we review how the field was propelled by the development of novel techniques and approaches. The glucagon radioimmunoassay and islet isolation are methods that now seem trivial, but for decades they were crucial in defining the biology of the pancreatic alpha cell and the role of glucagon in glucose homeostasis. More recently, mouse models have become the main workhorse of this research effort, if not of biomedical research in general. The mouse model allowed detailed mechanistic studies that are revealing alpha cell functions beyond its canonical glucoregulatory role. A recent profusion of gene expression and transcription regulation studies is providing new vistas into what constitutes alpha cell identity. In particular, the combination of transcriptomic techniques with functional recordings promises to move molecular guesswork into real-time physiology. The challenge right now is not to get enamored with these powerful techniques and to make sure that the research continues to be transformative and paradigm shifting. We should imagine a future in which the biology of the alpha cell will be studied at single-cell resolution, non-invasively, and in real time in the human body.
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Affiliation(s)
- Julia K Panzer
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Alejandro Caicedo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
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26
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Oteng AB, Pittala S, Kliewer A, Qiu Y, Wess J. Hepatic GRK2 is dispensable for glucose homeostasis and other key metabolic parameters in mice. Mol Metab 2024; 79:101866. [PMID: 38159884 PMCID: PMC10809122 DOI: 10.1016/j.molmet.2023.101866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 12/24/2023] [Accepted: 12/27/2023] [Indexed: 01/03/2024] Open
Abstract
OBJECTIVE G-protein-coupled receptor (GPCR) kinases (GRKs) abrogate GPCR signaling by promoting receptor desensitization and internalization. Accumulating evidence suggests that GRK2 represents an important regulator of GPCR-mediated effects on systemic glucose metabolism, obesity, and insulin resistance. Despite the key role of the liver in maintaining euglycemia, the potential metabolic relevance of hepatic GRK2 has yet to be examined. Thus, the goal of this study was to explore the potential role of hepatic GRK2 in maintaining glucose homeostasis and other key metabolic functions. METHODS To address this question, we generated mice that showed a ∼90% reduction in GRK2 protein expression selectively in hepatocytes (Hep-GRK2-KO mice) and subjected these mice, together with their control littermates, to systematic metabolic phenotyping studies. RESULTS We found that Hep-GRK2-KO mice maintained on regular chow did not differ significantly from their control littermates in glycemia, glucose tolerance, insulin sensitivity, in vivo gluconeogenesis, and glucagon-induced hyperglycemia. We obtained similar findings when we analyzed Hep-GRK2-KO mice and control littermates consuming an obesogenic high-fat diet. Likewise, plasma levels of insulin, glucagon, free fatty acids, and ketone bodies remained unaffected by the lack of hepatocyte GRK2. The same was true when we examined the expression levels of key genes regulating hepatic glucose and fatty acid metabolism. CONCLUSION In summary, our data suggest that hepatocyte GRK2 is dispensable for systemic glucose homeostasis and other key metabolic functions in both lean and obese mice. This finding suggests that drug development efforts aimed at inhibiting GRK2 to improve impaired glucose homeostasis and insulin sensitivity need to focus on other metabolically important tissues.
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Affiliation(s)
- Antwi-Boasiako Oteng
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA.
| | - Srinivas Pittala
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA
| | - Andrea Kliewer
- Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Yishu Qiu
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892, USA.
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27
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Himuro M, Wakabayashi Y, Taguchi T, Katahira T, Suzuki L, Iida H, Ogihara T, Nishida Y, Sasaki S, Lynn FC, Hiraoka Y, Oshima S, Okamoto R, Fujitani Y, Watada H, Miyatsuka T. Novel time-resolved reporter mouse reveals spatial and transcriptional heterogeneity during alpha cell differentiation. Diabetologia 2024; 67:156-169. [PMID: 37870650 DOI: 10.1007/s00125-023-06028-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 08/25/2023] [Indexed: 10/24/2023]
Abstract
AIMS/HYPOTHESIS Glucagon-expressing pancreatic alpha cells have attracted much attention for their plasticity to transdifferentiate into insulin-producing beta cells; however, it remains unclear precisely when, and from where, alpha cells emerge and what regulates alpha cell fate. We therefore explored the spatial and transcriptional heterogeneity of alpha cell differentiation using a novel time-resolved reporter system. METHODS We established the mouse model, 'Gcg-Timer', in which newly generated alpha cells can be distinguished from more-differentiated cells by their fluorescence. Fluorescence imaging and transcriptome analysis were performed with Gcg-Timer mice during the embryonic and postnatal stages. RESULTS Fluorescence imaging and flow cytometry demonstrated that green fluorescence-dominant cells were present in Gcg-Timer mice at the embryonic and neonatal stages but not after 1 week of age, suggesting that alpha cell neogenesis occurs during embryogenesis and early neonatal stages under physiological conditions. Transcriptome analysis of Gcg-Timer embryos revealed that the mRNAs related to angiogenesis were enriched in newly generated alpha cells. Histological analysis revealed that some alpha cells arise close to the pancreatic ducts, whereas the others arise away from the ducts and adjacent to the blood vessels. Notably, when the glucagon signal was suppressed by genetic ablation or by chemicals, such as neutralising glucagon antibody, green-dominant cells emerged again in adult mice. CONCLUSIONS/INTERPRETATION Novel time-resolved analysis with Gcg-Timer reporter mice uncovered spatiotemporal features of alpha cell neogenesis that will enhance our understanding of cellular identity and plasticity within the islets. DATA AVAILABILITY Raw and processed RNA sequencing data for this study has been deposited in the Gene Expression Omnibus under accession number GSE229090.
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Affiliation(s)
- Miwa Himuro
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yuka Wakabayashi
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Tomomi Taguchi
- Department of Endocrinology, Diabetes and Metabolism, Kitasato University School of Medicine, Sagamihara, Japan
| | - Takehiro Katahira
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Luka Suzuki
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hitoshi Iida
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takeshi Ogihara
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yuya Nishida
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Shugo Sasaki
- Diabetes Research Group, BC Children's Hospital Research Institute, Vancouver, BC, Canada
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Francis C Lynn
- Diabetes Research Group, BC Children's Hospital Research Institute, Vancouver, BC, Canada
| | - Yuichi Hiraoka
- Laboratory of Genome Editing for Biomedical Research, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shigeru Oshima
- Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ryuichi Okamoto
- Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshio Fujitani
- Laboratory of Developmental Biology & Metabolism, Institute for Molecular & Cellular Regulation, Gunma University, Maebashi, Japan
| | - Hirotaka Watada
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
- Center for Identification of Diabetic Therapeutic Targets, Juntendo University Graduate School of Medicine, Tokyo, Japan.
| | - Takeshi Miyatsuka
- Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
- Department of Endocrinology, Diabetes and Metabolism, Kitasato University School of Medicine, Sagamihara, Japan.
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Coulter-Parkhill A, Tanday N, Cobice D, McLaughlin CM, McClean S, Gault VA, Irwin N. Sustained metabolic benefits of ΔTRTX-Ac1, a tarantula venom-derived peptide, when administered together with exenatide in high-fat fed mice. Diabetes Obes Metab 2024; 26:329-338. [PMID: 37818589 DOI: 10.1111/dom.15319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/22/2023] [Accepted: 09/24/2023] [Indexed: 10/12/2023]
Abstract
AIM The aim of the present study was to assess the long-term therapeutic efficacy of a recently discovered 28 amino acid peptide, Δ-theraphotoxin-Ac1 (Δ-TRTX-Ac1), originally isolated from venom of the Aphonopelma chalcodes tarantula. Δ-TRTX-Ac has previously been shown to improve pancreatic beta-cell function and suppress appetite. MATERIALS AND METHODS Δ-TRTX-Ac1 was administered twice daily in high-fat fed (HFF) mice with streptozotocin (STZ)-induced insulin deficiency, namely HFF/STZ mice, for 28 days both alone and in combination with the venom-derived glucagon-like peptide-1 (GLP-1) mimetic, exenatide. RESULTS Initial pharmacokinetic profiling of ΔTRTX-Ac1 revealed a plasma half-life of 2 h in mice, with ΔTRTX-Ac1 also evidenced in the pancreas 12 h post-injection. Accordingly, HFF-STZ mice received twice-daily injections of Δ-TRTX-Ac1, exenatide or a combination of both peptides for 28 days. As anticipated, HFF/STZ mice presented with hyperglycaemia, impaired glucose tolerance, decreased plasma and pancreatic insulin and disturbed pancreatic islet morphology. Administration of ΔTRTX-Ac1 reduced body weight, improved glucose tolerance and augmented pancreatic insulin content while decreasing glucagon content. Exenatide had similar benefits on body weight and pancreatic hormone content while also reducing circulating glucose. ΔTRTX-Ac1 decreased energy expenditure on day 28 whereas exenatide had no impact. All treatment regimens restored pancreatic islet and beta-cell area towards lean control levels, which was linked to significantly elevated beta-cell proliferation rates. In terms of benefits of combined ΔTRTX-Ac1 and exenatide treatment over individual agents, there was augmentation of glucose tolerance and ambulatory activity with combination therapy, and these mice presented with increased pancreatic glucagon. CONCLUSION These data highlight the therapeutic promise of ΔTRTX-Ac1 for diabetes, with suggestion that benefits could be enhanced through combined administration with exenatide.
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Affiliation(s)
| | - Neil Tanday
- Diabetes Research Centre, Ulster University, Coleraine, UK
| | - Diego Cobice
- Diabetes Research Centre, Ulster University, Coleraine, UK
| | | | | | - Victor A Gault
- Diabetes Research Centre, Ulster University, Coleraine, UK
| | - Nigel Irwin
- Diabetes Research Centre, Ulster University, Coleraine, UK
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Mashayekhi M, Nian H, Mayfield D, Devin JK, Gamboa JL, Yu C, Silver HJ, Niswender K, Luther JM, Brown NJ. Weight Loss-Independent Effect of Liraglutide on Insulin Sensitivity in Individuals With Obesity and Prediabetes. Diabetes 2024; 73:38-50. [PMID: 37874653 PMCID: PMC10784656 DOI: 10.2337/db23-0356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 10/16/2023] [Indexed: 10/26/2023]
Abstract
Metabolic effects of glucagon-like peptide 1 (GLP-1) receptor agonists are confounded by weight loss and not fully recapitulated by increasing endogenous GLP-1. We tested the hypothesis that GLP-1 receptor (GLP-1R) agonists exert weight loss-independent, GLP-1R-dependent effects that differ from effects of increasing endogenous GLP-1. Individuals with obesity and prediabetes were randomized to receive for 14 weeks the GLP-1R agonist liraglutide, a hypocaloric diet, or the dipeptidyl peptidase 4 (DPP-4) inhibitor sitagliptin. The GLP-1R antagonist exendin(9-39) and placebo were administered in a two-by-two crossover study during mixed-meal tests. Liraglutide and diet, but not sitagliptin, caused weight loss. Liraglutide improved insulin sensitivity measured by HOMA for insulin resistance (HOMA-IR), the updated HOMA model (HOMA2), and the Matsuda index after 2 weeks, prior to weight loss. Liraglutide decreased fasting and postprandial glucose levels, and decreased insulin, C-peptide, and fasting glucagon levels. In contrast, diet-induced weight loss improved insulin sensitivity by HOMA-IR and HOMA2, but not the Matsuda index, and did not decrease glucose levels. Sitagliptin increased endogenous GLP-1 and GIP values without altering insulin sensitivity or fasting glucose levels, but decreased postprandial glucose and glucagon levels. Notably, sitagliptin increased GIP without altering weight. Acute GLP-1R antagonism increased glucose levels in all groups, increased the Matsuda index and fasting glucagon level during liraglutide treatment, and increased endogenous GLP-1 values during liraglutide and sitagliptin treatments. Thus, liraglutide exerts rapid, weight loss-independent, GLP-1R-dependent effects on insulin sensitivity that are not achieved by increasing endogenous GLP-1. ARTICLE HIGHLIGHTS Metabolic benefits of glucagon-like peptide 1 (GLP-1) receptor agonists are confounded by weight loss and are not fully achieved by increasing endogenous GLP-1 through dipeptidyl peptidase 4 (DPP-4) inhibition. We investigated weight loss-independent, GLP-1 receptor (GLP-1R)-dependent metabolic effects of liraglutide versus a hypocaloric diet or the DPP-4 inhibitor sitagliptin. GLP-1R antagonism with exendin(9-39) was used to assess GLP-1R-dependent effects during mixed meals. Liraglutide improved insulin sensitivity and decreased fasting and postprandial glucose prior to weight loss, and these benefits were reversed by exendin(9-39). GLP-1R agonists exert rapid, weight loss-independent, GLP-1R-dependent effects on insulin sensitivity not achieved by increasing endogenous GLP-1.
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Affiliation(s)
- Mona Mashayekhi
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN
| | - Hui Nian
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Dustin Mayfield
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN
| | - Jessica K. Devin
- UCHealth Endocrinology, Yampa Valley Medical Center, Steamboat Springs, CO
| | - Jorge L. Gamboa
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN
| | - Chang Yu
- Department of Population Health, NYU Grossman School of Medicine, New York, NY
| | - Heidi J. Silver
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, Vanderbilt University Medical Center, Nashville, TN
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN
| | - Kevin Niswender
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN
| | - James M. Luther
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical Center, Nashville, TN
| | - Nancy J. Brown
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT
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30
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Lim JJ, Sequeira-Bisson IR, Yip WCY, Lu LW, Miles-Chan JL, Poppitt SD. Intra-pancreatic fat is associated with high circulating glucagon and GLP-1 concentrations following whey protein ingestion in overweight women with impaired fasting glucose: A randomised controlled trial. Diabetes Res Clin Pract 2024; 207:111084. [PMID: 38154534 DOI: 10.1016/j.diabres.2023.111084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/13/2023] [Accepted: 12/25/2023] [Indexed: 12/30/2023]
Abstract
AIM Intra-pancreatic fat deposition (IPFD) while hypothesised to impair beta-cell function, its impact on alpha-cells remains unclear. We evaluated the association between IPFD and markers of pancreatic cells function using whey protein. METHODS Twenty overweight women with impaired fasting glucose (IFG) and low or high IPFD (<4.66% vs ≥4.66%) consumed 3 beverage treatments: 0 g (water control), 12.5 g (low-dose) and 50.0 g (high-dose) whey protein, after an overnight fast, in randomised order. Blood glucose, insulin, C-peptide, glucagon, gastric-inhibitory polypeptide (GIP), glucagon-like peptide-1 (GLP-1) and amylin were analysed postprandially over 4 h. Incremental area-under-the-curve (iAUC), incremental maximum concentration (iCmax), and time to maximum concentration (Tmax) for these were compared between IPFD groups using repeated measures linear mixed models, also controlled for age (pcov). RESULTS iAUC and iCmax glucose and insulin while similar between the two IPFD groups, high IPFD and ageing contributed to higher postprandial glucagon (iAUC: p = 0.012; pcov = 0.004; iCmax: p = 0.069; pcov = 0.021) and GLP-1 (iAUC: p = 0.006; pcov = 0.064; iCmax: p = 0.011; pcov = 0.122) concentrations. CONCLUSION In our cohort, there was no evidence that IPFD impaired protein-induced insulin secretion. Conversely, IPFD may be associated with increased protein-induced glucagon secretion, a novel observation which warrants further investigation into its relevance in the pathogenesis of dysglycaemia and type-2 diabetes.
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Affiliation(s)
- Jia Jiet Lim
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland, New Zealand; Riddet Institute, Palmerston North, New Zealand; High Value Nutrition, National Science Challenge, Auckland, New Zealand.
| | - Ivana R Sequeira-Bisson
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland, New Zealand; Riddet Institute, Palmerston North, New Zealand; High Value Nutrition, National Science Challenge, Auckland, New Zealand
| | - Wilson C Y Yip
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland, New Zealand; High Value Nutrition, National Science Challenge, Auckland, New Zealand
| | - Louise W Lu
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland, New Zealand; High Value Nutrition, National Science Challenge, Auckland, New Zealand
| | - Jennifer L Miles-Chan
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland, New Zealand; Riddet Institute, Palmerston North, New Zealand; High Value Nutrition, National Science Challenge, Auckland, New Zealand
| | - Sally D Poppitt
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland, New Zealand; Riddet Institute, Palmerston North, New Zealand; High Value Nutrition, National Science Challenge, Auckland, New Zealand; Department of Medicine, University of Auckland, Auckland, New Zealand
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31
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Abstract
The following review focuses on the scientific studies related to the role of endocannabinoid system (ECS) in pancreatic islet physiology and dysfunction. Different natural or synthetic agonists and antagonists have been suggested as an alternative treatment for diabetes, obesity and metabolic syndrome. Therapeutic use of Cannabis led to the discovery and characterization of the ECS, a signaling complex involved in regulation of various physiological processes, including food intake and metabolism. After the development of different agonists and antagonists, evidence have demonstrated the presence and activity of cannabinoid receptors in several organs and tissues, including pancreatic islets. Insulin and glucagon expression, stimulated secretion, and the development of diabetes and other metabolic disorders have been associated with the activity and modulation of ECS in pancreatic islets. However, according to the animal model and experimental design, either endogenous or pharmacological ligands of cannabinoid receptors have guided to contradictory and paradoxical results that suggest a complex physiological interaction. In consensus, ECS activity modulates insulin and glucagon secretions according to glucose in media; over-stimulation of cannabinoid receptors affects islets negatively, leading to glucose intolerance, meanwhile the treatment with antagonists in diabetic models and humans suggests an improvement in islets function.
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Affiliation(s)
- Edgardo Cortes-Justo
- Posgrado e Investigación, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico NacionalMexico CityMexico
| | - Sergio H Garfias-Ramírez
- Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Coyoacán, Mexico
| | - Alonso Vilches-Flores
- Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Coyoacán, Mexico
- CONTACT Alonso Vilches-Flores Universidad Nacional Autónoma de México, Facultad de Estudios Superiores Iztacala. Edif.A4 Lab 4, Los Reyes Iztacala, Tlalnepantla54090, Mexico
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32
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Lasher AT, Sun LY. Distinct physiological characteristics and altered glucagon signaling in GHRH knockout mice: Implications for longevity. Aging Cell 2023; 22:e13985. [PMID: 37667562 PMCID: PMC10726877 DOI: 10.1111/acel.13985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/10/2023] [Accepted: 08/11/2023] [Indexed: 09/06/2023] Open
Abstract
Our previous research has demonstrated that mice lacking functional growth hormone-releasing hormone (GHRH) exhibit distinct physiological characteristics, including an extended lifespan, a preference for lipid utilization during rest, mild hypoglycemia, and heightened insulin sensitivity. They also show a further increase in lifespan when subjected to caloric restriction. These findings suggest a unique response to fasting, which motivated our current study on the response to glucagon, a key hormone released from the pancreas during fasting that regulates glucose levels, energy expenditure, and metabolism. Our study investigated the effects of an acute glucagon challenge on female GHRH knockout mice and revealed that they exhibit reduced glucose production, likely due to suppressed gluconeogenesis. However, these mice showed an increase in energy expenditure. We also observed alterations in pancreatic islet architecture, with smaller islets and a reduction of insulin-producing beta cells but no changes in glucagon-producing alpha cells. Additionally, the analysis of hepatic glucagon signaling showed a decrease in glucagon receptor expression and phosphorylated CREB. In conclusion, our findings suggest that the unique metabolic phenotype observed in these long-lived mice may be partly explained by changes in glucagon signaling. Further exploration of this pathway may lead to new insights into the regulation of longevity in mammals.
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Affiliation(s)
- A. Tate Lasher
- Department of BiologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Liou Y. Sun
- Department of BiologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
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33
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Weir GC, Bonner-Weir S. Conflicting Views About Interactions Between Pancreatic α-Cells and β-Cells. Diabetes 2023; 72:1741-1747. [PMID: 37983524 PMCID: PMC10658062 DOI: 10.2337/db23-0292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 08/16/2023] [Indexed: 11/22/2023]
Abstract
In type 1 diabetes, the reduced glucagon response to insulin-induced hypoglycemia has been used to argue that β-cell secretion of insulin is required for the full glucagon counterregulatory response. For years, the concept has been that insulin from the β-cell core flows downstream to suppress glucagon secretion from the α-cells in the islet mantle. This core-mantle relationship has been supported by perfused pancreas studies that show marked increases in glucagon secretion when insulin was neutralized with antisera. Additional support comes from a growing number of studies focused on vascular anatomy and blood flow. However, in recent years this core-mantle view has generated less interest than the argument that optimal insulin secretion is due to paracrine release of glucagon from α-cells stimulating adjacent β-cells. This mechanism has been evaluated by knockout of β-cell receptors and impairment of α-cell function by inhibition of Gi designer receptors exclusively activated by designer drugs. Other studies that support this mechanism have been obtained by pharmacological blocking of glucagon-like peptide 1 receptor in humans. While glucagon has potent effects on β-cells, there are concerns with the suggested paracrine mechanism, since some of the supporting data are from isolated islets. The study of islets in static incubation or perifusion systems can be informative, but the normal paracrine relationships are disrupted by the isolation process. While this complicates interpretation of data, arguments supporting paracrine interactions between α-cells and β-cells have growing appeal. We discuss these conflicting views of the relationship between pancreatic α-cells and β-cells and seek to understand how communication depends on blood flow and/or paracrine mechanisms.
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Affiliation(s)
- Gordon C. Weir
- Joslin Diabetes Center, Harvard Medical School, Boston, MA
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34
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Ang T, Mason SA, Dao GM, Bruce CR, Kowalski GM. The impact of a single dose of whey protein on glucose flux and metabolite profiles in normoglycemic males: insights into glucagon and insulin biology. Am J Physiol Endocrinol Metab 2023; 325:E688-E699. [PMID: 37877796 DOI: 10.1152/ajpendo.00182.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/26/2023]
Abstract
Protein ingestion concurrently stimulates euglycemic glucagon and insulin secretion, a response that is particularly robust with rapidly absorbing proteins. Previously, we have shown that ingestion of repeated doses of rapidly absorbing whey protein equally stimulated endogenous glucose production (EGP) and glucose disposal (Rd), thus explaining the preservation of euglycemia. Here, we aimed to determine if a smaller single dose of whey could elicit a large enough glucagon and insulin response to stimulate glucose flux. Therefore, in normoglycemic young adult males (n = 10; age ∼26; BMI ∼25), using [6,6-2H2] glucose tracing and quantitative targeted metabolite profiling, we determined the metabolic response to a single 25 g "standard" dose of whey protein. Whey protein ingestion did not alter glycemia, but increased circulating glucagon (peak 4-fold basal), insulin (peak 6-fold basal), amino acids, and urea while also reducing free fatty acid (FFA) and glycerol concentrations. Interestingly, the postprandial insulin response was driven by both a stimulation of insulin secretion and marked reduction in hepatic insulin clearance. Whey protein ingestion resulted in a modest stimulation of EGP and Rd, both peaking at ∼20% above baseline 1 h after protein ingestion. These findings demonstrate that the ingestion of a single standard serving of whey protein can induce a euglycemic glucagon and insulin response that stimulates glucose flux. We speculate on a theory that could potentially explain how glucagon and insulin synergistically provide hardwired control of nitrogen and glucose homeostasis.NEW & NOTEWORTHY Protein ingestion concurrently stimulates glucagon and insulin secretion. Here we show that in normoglycemic males, ingestion of a single "standard" 25 g serving of rapidly absorbing whey protein drives a sufficiently large glucagon and insulin response, such that it simultaneously increases endogenous glucose production and glucose disposal. We speculate on a novel theory that could potentially explain how the antagonistic/synergistic actions of glucagon and insulin simultaneously provide tight control of glucose and nitrogen homeostasis.
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Affiliation(s)
- Teddy Ang
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
- School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
| | - Shaun A Mason
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
- School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
| | - Giang M Dao
- Metabolic Research Unit, School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Clinton R Bruce
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
- School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
| | - Greg M Kowalski
- Institute for Physical Activity and Nutrition, School of Exercise and Nutrition Science, Deakin University, Geelong, Victoria, Australia
- Metabolic Research Unit, School of Medicine, Deakin University, Geelong, Victoria, Australia
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Bowman P, Patel KA, McDonald TJ, Holst JJ, Hartmann B, Leveridge M, Shields BM, Hammersley S, Spaull SR, Knight BA, Flanagan SE, Shepherd MH, Andrews RC, Hattersley AT. Incretin hormone responses to carbohydrate and protein/fat are preserved in adults with sulfonylurea-treated KCNJ11 neonatal diabetes. J Diabetes Investig 2023; 14:1378-1382. [PMID: 37602910 PMCID: PMC10688132 DOI: 10.1111/jdi.14071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 08/01/2023] [Accepted: 08/07/2023] [Indexed: 08/22/2023] Open
Abstract
The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are thought to be the main drivers of insulin secretion in individuals with sulfonylurea (SU)-treated KCNJ11 permanent neonatal diabetes. The aim of this study was to assess for the first time the incretin hormone response to carbohydrate and protein/fat in adults with sulfonylurea-treated KCNJ11 permanent neonatal diabetes compared with that of controls without diabetes. Participants were given a breakfast high in carbohydrate and an isocaloric breakfast high in protein/fat on two different mornings. Incremental area under the curve and total area under the curve (0-240 minutes) for total GLP-1 and GIP were compared between groups, using non-parametric statistical methods. Post-meal GLP-1 and GIP secretion were similar in cases and controls, suggesting this process is adenosine triphosphate-sensitive potassium channel-independent. Future research will investigate whether treatments targeting the incretin pathway are effective in individuals with KCNJ11 permanent neonatal diabetes who do not have good glycemic control on sulfonylurea alone.
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Affiliation(s)
- Pamela Bowman
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Kashyap A Patel
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Timothy J McDonald
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Jens J Holst
- Faculty of Health and Medical SciencesUniversity of CopenhagenKobenhavnDenmark
| | - Bolette Hartmann
- Faculty of Health and Medical SciencesUniversity of CopenhagenKobenhavnDenmark
| | - Maria Leveridge
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Beverley M Shields
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
| | - Suzie Hammersley
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Steve R Spaull
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Bridget A Knight
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Sarah E Flanagan
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
| | - Maggie H Shepherd
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
| | - Rob C Andrews
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
| | - Andrew T Hattersley
- University of Exeter Medical SchoolExeterUK
- Exeter NIHR Clinical Research FacilityExeterUK
- NIHR Exeter Biomedical Research Centre (BRC)ExeterUK
- Royal Devon University Healthcare NHS Foundation TrustExeterUK
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Caicedo A, Huising MO, Wess J. An Intraislet Paracrine Signaling Pathway That Enables Glucagon to Stimulate Pancreatic β-Cells. Diabetes 2023; 72:1748-1750. [PMID: 37983525 PMCID: PMC10658067 DOI: 10.2337/dbi23-0023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 09/19/2023] [Indexed: 11/22/2023]
Affiliation(s)
- Alejandro Caicedo
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL
| | - Mark O. Huising
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, CA
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, Davis, CA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD
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Rasmussen C, Richter MM, Jensen NJ, Heinz N, Hartmann B, Holst JJ, Kjeldsen SAS, Wewer Albrechtsen NJ. Preanalytical impact on the accuracy of measurements of glucagon, GLP-1 and GIP in clinical trials. Scand J Clin Lab Invest 2023; 83:591-598. [PMID: 38127365 DOI: 10.1080/00365513.2023.2294470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND Plasma concentrations of glucagon, GLP-1 and GIP are reported in numerous clinical trials as outcome measures but preanalytical guidelines are lacking. We addressed the impact of commonly used blood containers in metabolic research on measurements of glucagon, GLP-1 and GIP in humans. METHODS Seventeen overweight individuals were subjected to an overnight fast followed by an intravenous infusion of amino acids to stimulate hormonal secretion. Blood was sampled into five containers: EDTA-coated tubes supplemented with DMSO (control), a neprilysin inhibitor, aprotinin (a kallikrein inhibitor) or a DPP-4 inhibitor, and P800 tubes. Plasma was kept on ice before and after centrifugation and stored at -80 Celsius until batch analysis using validated sandwich ELISAs or radioimmunoassays (RIA). RESULTS Measures of fasting plasma glucagon did not depend on sampling containers, whether measured by ELISA or RIA. Amino acid-induced hyperglucagonemia was numerically higher when blood was collected into P800 tubes or tubes with aprotinin. The use of p800 tubes resulted in higher concentrations of GLP-1 by RIA compared to control tubes but not for measurements with sandwich ELISA. Plasma concentrations of GIP measured by ELISA were higher in control tubes and negatively affected by P800 and the addition of aprotinin. CONCLUSIONS The choice of blood containers impacts on measurements of plasma concentrations of glucagon, GLP-1 and GIP, and based on this study, we recommend using EDTA-coated tubes without protease inhibitors or P800 tubes for measurements of glucagon, GLP-1 and GIP in clinical trials.
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Affiliation(s)
- Christine Rasmussen
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael M Richter
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Copenhagen, 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
| | - Niklas Heinz
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Endocrinology, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Bolette Hartmann
- 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 Nordic Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sasha A S Kjeldsen
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai J Wewer Albrechtsen
- Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Mistry PK, Garcia-Tsao G. Liver Transplantation for Mahvash Disease, an Inborn Error of Metabolism. N Engl J Med 2023; 389:2010-2013. [PMID: 37991861 DOI: 10.1056/nejme2310332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Affiliation(s)
- Pramod K Mistry
- From the Department of Medicine and Section of Digestive Diseases, Yale University School of Medicine, New Haven (P.K.M., G.G.-T.), and the Department of Medicine and Section of Digestive Diseases, Veterans Affairs Connecticut Healthcare System, West Haven (G.G.-T.) - both in Connecticut
| | - Guadalupe Garcia-Tsao
- From the Department of Medicine and Section of Digestive Diseases, Yale University School of Medicine, New Haven (P.K.M., G.G.-T.), and the Department of Medicine and Section of Digestive Diseases, Veterans Affairs Connecticut Healthcare System, West Haven (G.G.-T.) - both in Connecticut
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Welch AA, Farahani RA, Egan AM, Laurenti MC, Zeini M, Vella M, Bailey KR, Cobelli C, Dalla Man C, Matveyenko A, Vella A. Glucagon-like peptide-1 receptor blockade impairs islet secretion and glucose metabolism in humans. J Clin Invest 2023; 133:e173495. [PMID: 37751301 PMCID: PMC10645389 DOI: 10.1172/jci173495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 09/12/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUNDProglucagon can be processed to glucagon-like peptide1 (GLP-1) within the islet, but its contribution to islet function in humans remains unknown. We sought to understand whether pancreatic GLP-1 alters islet function in humans and whether this is affected by type 2 diabetes.METHODSWe therefore studied individuals with and without type 2 diabetes on two occasions in random order. On one occasion, exendin 9-39, a competitive antagonist of the GLP-1 Receptor (GLP1R), was infused, while on the other, saline was infused. The tracer dilution technique ([3-3H] glucose) was used to measure glucose turnover during fasting and during a hyperglycemic clamp.RESULTSExendin 9-39 increased fasting glucose concentrations; fasting islet hormone concentrations were unchanged, but inappropriate for the higher fasting glucose observed. In people with type 2 diabetes, fasting glucagon concentrations were markedly elevated and persisted despite hyperglycemia. This impaired suppression of endogenous glucose production by hyperglycemia.CONCLUSIONThese data show that GLP1R blockade impairs islet function, implying that intra-islet GLP1R activation alters islet responses to glucose and does so to a greater degree in people with type 2 diabetes.TRIAL REGISTRATIONThis study was registered at ClinicalTrials.gov NCT04466618.FUNDINGThe study was primarily funded by NIH NIDDK DK126206. AV is supported by DK78646, DK116231 and DK126206. CDM was supported by MIUR (Italian Minister for Education) under the initiative "Departments of Excellence" (Law 232/2016).
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Affiliation(s)
- Andrew A. Welch
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Rahele A. Farahani
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Aoife M. Egan
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Marcello C. Laurenti
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Maya Zeini
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Max Vella
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Kent R. Bailey
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Aleksey Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Adrian Vella
- Division of Endocrinology, Diabetes & Metabolism, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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Ternhamar T, Møller A, Martinussen C, Svane MS, Hindsø M, Jørgensen NB, Dirksen C, Jensen JEB, Hartmann B, Holst JJ, Kiens B, Madsbad S, Bojsen-Møller KN. The effects of postprandial exercise and meal glycemic index on plasma glucose and glucoregulatory hormone responses after Roux-en-Y gastric bypass. Am J Physiol Endocrinol Metab 2023; 325:E540-E551. [PMID: 37755455 DOI: 10.1152/ajpendo.00176.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 09/18/2023] [Accepted: 09/18/2023] [Indexed: 09/28/2023]
Abstract
Postprandial hypoglycemia is a complication of Roux-en-Y gastric bypass (RYGB), but the effects of postprandial exercise and meal glycemic index (GI) on postprandial glucose and glucoregulatory hormone responses are unknown. Ten RYGB-operated and 10 age and weight-matched unoperated women completed four test days in random order ingesting mixed meals with high GI (HGI, GI = 93) or low GI (LGI, GI = 54), but matched on energy and macronutrient content. Ten minutes after meal completion, participants rested or cycled for 30 min at 70% of maximum oxygen uptake (V̇o2max). Blood was collected for 4 h. Postprandial exercise did not lower plasma nadir glucose in RYGB after HGI (HGI/rest 3.7 ± 0.5 vs. HGI/Ex 4.1 ± 0.4 mmol/L, P = 0.070). Replacing HGI with LGI meals raised glucose nadir in RYGB (LGI/rest 4.1 ± 0.5 mmol/L, P = 0.034) and reduced glucose excursions (Δpeak-nadir) but less so in RYGB (-14% [95% CI: -27; -1]) compared with controls (-33% [-51; -14]). Insulin responses mirrored glucose concentrations. Glucagon-like peptide 1 (GLP-1) responses were greater in RYGB versus controls, and higher with HGI versus LGI. Glucose-dependent insulinotropic polypeptide (GIP) responses were greater after HGI versus LGI in both groups. Postexercise glucagon responses were lower in RYGB than controls, and noradrenaline responses tended to be lower in RYGB, whereas adrenaline responses were similar between groups. In conclusion, moderate intensity cycling shortly after meal intake did not increase the risk of postprandial hypoglycemia after RYGB. The low GI meal increased nadir glucose and reduced glucose excursions compared with the high GI meal. RYGB participants had lower postexercise glucagon responses compared with controls.NEW & NOTEWORTHY We investigate the effect of moderate exercise after a high or a low glycemic index meal on nadir glucose and glucoregulatory hormones in gastric bypass-operated individuals and in matched unoperated controls. Cycling shortly after meal intake did not increase the risk of hypoglycemia in operated individuals. The low glycemic index meal increased glucose nadir and reduced excursions compared with the high glycemic index meal. Operated individuals had lower postexercise glucagon responses compared with controls.
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Affiliation(s)
- Tummas Ternhamar
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Andreas Møller
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | | | - Maria S Svane
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Morten Hindsø
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Nils B Jørgensen
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Carsten Dirksen
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Jens-Erik Beck Jensen
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
- Institute of Clinical Medicine, Faculty of Health, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health, University of Copenhagen, Copenhagen, Denmark
| | - Bente Kiens
- Department of Nutrition, Exercise, and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Sten Madsbad
- Department of Endocrinology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
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Ron I, Mdah R, Zemet R, Ulman RY, Rathaus M, Brandt B, Mazaki-Tovi S, Hemi R, Barhod E, Tirosh A. Adipose tissue-derived FABP4 mediates glucagon-stimulated hepatic glucose production in gestational diabetes. Diabetes Obes Metab 2023; 25:3192-3201. [PMID: 37449442 DOI: 10.1111/dom.15214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/14/2023] [Accepted: 06/26/2023] [Indexed: 07/18/2023]
Abstract
AIMS One of the most common complications of pregnancy is gestational diabetes mellitus (GDM), which may result in significant health threats of the mother, fetus and the newborn. Fatty acid-binding protein 4 (FABP4) is an adipokine that regulates glucose homeostasis by promoting glucose production and liver insulin resistance in mouse models. FABP4 levels are increased in GDM and correlates with maternal indices of insulin resistance, with a rapid decline post-partum. We therefore aimed to determine the tissue origin of elevated circulating FABP4 levels in GDM and to assess its potential contribution in promoting glucagon-induced hepatic glucose production. MATERIALS AND METHODS FABP4 protein and gene expression was determined in biopsies from placenta, subcutaneous (sWAT) and visceral (vWAT) white adipose tissues from GDM and normoglycaemic pregnant women. FABP4 differential contribution in glucagon-stimulated hepatic glucose production was tested in conditioned media before and after its immune clearance. RESULTS We showed that FABP4 is expressed in placenta, sWAT and vWAT of pregnant women at term, with a significant increase in its secretion from vWAT of women with GDM compared with normoglycaemic pregnant women. Neutralizing FABP4 from both normoglycaemic pregnant women and GDM vWAT secretome, resulted in a decrease in glucagon-stimulated hepatic glucose production. CONCLUSIONS This study provides new insights into the role of adipose tissue-derived FABP4 in GDM, highlighting this adipokine, as a potential co-activator of glucagon-stimulated hepatic glucose production during pregnancy.
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Affiliation(s)
- Idit Ron
- The Dalia and David Arabov Endocrinology and Diabetes Research Center, Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, Tel-Hashomer, Israel
| | - Ragad Mdah
- The Dalia and David Arabov Endocrinology and Diabetes Research Center, Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, Tel-Hashomer, Israel
- Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Roni Zemet
- Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Hashomer, Israel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Rakefet Yoeli Ulman
- Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Moran Rathaus
- The Dalia and David Arabov Endocrinology and Diabetes Research Center, Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, Tel-Hashomer, Israel
| | - Benny Brandt
- Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Hashomer, Israel
- Department of Gynecologic Oncology, Hadassah Medical Center, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Shali Mazaki-Tovi
- Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
- Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Hashomer, Israel
| | - Rina Hemi
- The Dalia and David Arabov Endocrinology and Diabetes Research Center, Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, Tel-Hashomer, Israel
| | - Ehud Barhod
- The Dalia and David Arabov Endocrinology and Diabetes Research Center, Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, Tel-Hashomer, Israel
| | - Amir Tirosh
- The Dalia and David Arabov Endocrinology and Diabetes Research Center, Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, Tel-Hashomer, Israel
- Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
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Li J, Dang P, Li Z, Zhao T, Cheng D, Pan D, Yuan Y, Song W. Peroxisomal ERK mediates Akh/glucagon action and glycemic control. Cell Rep 2023; 42:113200. [PMID: 37796662 DOI: 10.1016/j.celrep.2023.113200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/18/2023] [Accepted: 09/15/2023] [Indexed: 10/07/2023] Open
Abstract
The enhanced response of glucagon and its Drosophila homolog, adipokinetic hormone (Akh), leads to high-caloric-diet-induced hyperglycemia across species. While previous studies have characterized regulatory components transducing linear Akh signaling promoting carbohydrate production, the spatial elucidation of Akh action at the organelle level still remains largely unclear. In this study, we find that Akh phosphorylates extracellular signal-regulated kinase (ERK) and translocates it to peroxisome via calcium/calmodulin-dependent protein kinase II (CaMKII) cascade to increase carbohydrate production in the fat body, leading to hyperglycemia. The mechanisms include that ERK mediates fat body peroxisomal conversion of amino acids into carbohydrates for gluconeogenesis in response to Akh. Importantly, Akh receptor (AkhR) or ERK deficiency, importin-associated ERK retention from peroxisome, or peroxisome inactivation in the fat body sufficiently alleviates high-sugar-diet-induced hyperglycemia. We also observe mammalian glucagon-induced hepatic ERK peroxisomal translocation in diabetic subjects. Therefore, our results conclude that the Akh/glucagon-peroxisomal-ERK axis is a key spatial regulator of glycemic control.
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Affiliation(s)
- Jiaying Li
- Department of Hepatobiliary and Pancreatic Surgery, Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China; TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430071, China
| | - Peixuan Dang
- Department of Hepatobiliary and Pancreatic Surgery, Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China; TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430071, China
| | - Zhen Li
- Department of Hepatobiliary and Pancreatic Surgery, Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
| | - Tujing Zhao
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Daojun Cheng
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
| | - Dingyu Pan
- Department of Hepatobiliary and Pancreatic Surgery, Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China.
| | - Yufeng Yuan
- Department of Hepatobiliary and Pancreatic Surgery, Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China; TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430071, China.
| | - Wei Song
- Department of Hepatobiliary and Pancreatic Surgery, Frontier Science Center for Immunology and Metabolism, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China; TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, Hubei 430071, China.
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Armour SL, Frueh A, Chibalina MV, Dou H, Argemi-Muntadas L, Hamilton A, Katzilieris-Petras G, Carmeliet P, Davies B, Moritz T, Eliasson L, Rorsman P, Knudsen JG. Glucose Controls Glucagon Secretion by Regulating Fatty Acid Oxidation in Pancreatic α-Cells. Diabetes 2023; 72:1446-1459. [PMID: 37494670 PMCID: PMC10545563 DOI: 10.2337/db23-0056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 07/16/2023] [Indexed: 07/28/2023]
Abstract
Whole-body glucose homeostasis is coordinated through secretion of glucagon and insulin from pancreatic islets. When glucose is low, glucagon is released from α-cells to stimulate hepatic glucose production. However, the mechanisms that regulate glucagon secretion from pancreatic α-cells remain unclear. Here we show that in α-cells, the interaction between fatty acid oxidation and glucose metabolism controls glucagon secretion. The glucose-dependent inhibition of glucagon secretion relies on pyruvate dehydrogenase and carnitine palmitoyl transferase 1a activity and lowering of mitochondrial fatty acid oxidation by increases in glucose. This results in reduced intracellular ATP and leads to membrane repolarization and inhibition of glucagon secretion. These findings provide a new framework for the metabolic regulation of the α-cell, where regulation of fatty acid oxidation by glucose accounts for the stimulation and inhibition of glucagon secretion. ARTICLE HIGHLIGHTS It has become clear that dysregulation of glucagon secretion and α-cell function plays an important role in the development of diabetes, but we do not know how glucagon secretion is regulated. Here we asked whether glucose inhibits fatty acid oxidation in α-cells to regulate glucagon secretion. We found that fatty acid oxidation is required for the inhibitory effects of glucose on glucagon secretion through reductions in ATP. These findings provide a new framework for the regulation of glucagon secretion by glucose.
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Affiliation(s)
- Sarah L. Armour
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Alexander Frueh
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Margarita V. Chibalina
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
| | - Haiqiang Dou
- Department of Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lidia Argemi-Muntadas
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Alexander Hamilton
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Sciences in Malmö, Islet Cell Exocytosis, Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Georgios Katzilieris-Petras
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, Vlaams Instituut voor Biotechnologie (VIB), Department of Oncology, Leuven Cancer Institute, Katholieke Universiteit Leuven, Leuven, Belgium
- Laboratory of Angiogenesis and Vascular Heterogeneity, Department of Biomedicine, Aarhus University, Aarhus, Denmark
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong, People’s Republic of China
| | - Benjamin Davies
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, U.K
| | - Thomas Moritz
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lena Eliasson
- Department of Clinical Sciences in Malmö, Islet Cell Exocytosis, Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, U.K
- Department of Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Jakob G. Knudsen
- Section for Cell Biology and Physiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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44
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Ichikawa R, Takano K, Fujimoto K, Kobayashi M, Kitamura T, Shichiri M, Miyatsuka T. Robust increase in glucagon secretion after oral protein intake, but not after glucose or lipid intake in Japanese people without diabetes. J Diabetes Investig 2023; 14:1172-1174. [PMID: 37480216 PMCID: PMC10512907 DOI: 10.1111/jdi.14053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/16/2023] [Accepted: 06/22/2023] [Indexed: 07/23/2023] Open
Abstract
Few studies in Asian populations have analyzed how glucagon secretion is affected by ingested glucose, proteins or lipids, individually. To investigate the fluctuations of glucagon secretion after the intake of each of these nutrients, 10 healthy volunteers underwent oral loading tests using each of glucose, proteins and lipids, and blood levels of glucose, insulin and glucagon were measured every 30 min for 120 min. Whereas glucagon secretion was suppressed and minimally affected by oral glucose intake and lipid intake, respectively, oral protein intake robustly increased glucagon secretion, as well as insulin secretion. Further studies are needed to elucidate the mechanism by which protein loading increases glucagon secretion.
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Affiliation(s)
- Raishi Ichikawa
- Department of Diabetes, Endocrinology, Diabetes and MetabolismKitasato University, School of MedicineSagamiharaJapan
| | - Koji Takano
- Department of Diabetes, Endocrinology, Diabetes and MetabolismKitasato University, School of MedicineSagamiharaJapan
| | - Kazumi Fujimoto
- Department of Diabetes, Endocrinology, Diabetes and MetabolismKitasato University, School of MedicineSagamiharaJapan
| | - Masaki Kobayashi
- Metabolic Signal Research Center, Institute for Molecular and Cellular RegulationGunma UniversityMaebashiJapan
| | - Tadahiro Kitamura
- Metabolic Signal Research Center, Institute for Molecular and Cellular RegulationGunma UniversityMaebashiJapan
| | - Masayoshi Shichiri
- Department of Diabetes, Endocrinology, Diabetes and MetabolismKitasato University, School of MedicineSagamiharaJapan
| | - Takeshi Miyatsuka
- Department of Diabetes, Endocrinology, Diabetes and MetabolismKitasato University, School of MedicineSagamiharaJapan
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45
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Kahraman S, Shibue K, De Jesus DF, Kim H, Hu J, Manna D, Wagner B, Choudhary A, Kulkarni RN. Fluorescein-based sensors to purify human α-cells for functional and transcriptomic analyses. eLife 2023; 12:e85056. [PMID: 37732504 PMCID: PMC10567109 DOI: 10.7554/elife.85056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 09/11/2023] [Indexed: 09/22/2023] Open
Abstract
Pancreatic α-cells secrete glucagon, an insulin counter-regulatory peptide hormone critical for the maintenance of glucose homeostasis. Investigation of the function of human α-cells remains a challenge due to the lack of cost-effective purification methods to isolate high-quality α-cells from islets. Here, we use the reaction-based probe diacetylated Zinpyr1 (DA-ZP1) to introduce a novel and simple method for enriching live α-cells from dissociated human islet cells with ~95% purity. The α-cells, confirmed by sorting and immunostaining for glucagon, were cultured up to 10 days to form α-pseudoislets. The α-pseudoislets could be maintained in culture without significant loss of viability, and responded to glucose challenge by secreting appropriate levels of glucagon. RNA-sequencing analyses (RNA-seq) revealed that expression levels of key α-cell identity genes were sustained in culture while some of the genes such as DLK1, GSN, SMIM24 were altered in α-pseudoislets in a time-dependent manner. In conclusion, we report a method to sort human primary α-cells with high purity that can be used for downstream analyses such as functional and transcriptional studies.
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Affiliation(s)
- Sevim Kahraman
- Islet Cell and Regenerative Biology, Joslin Diabetes CenterBostonUnited States
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUnited States
- Harvard Stem Cell Institute, Harvard Medical SchoolBostonUnited States
| | - Kimitaka Shibue
- Islet Cell and Regenerative Biology, Joslin Diabetes CenterBostonUnited States
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUnited States
- Harvard Stem Cell Institute, Harvard Medical SchoolBostonUnited States
| | - Dario F De Jesus
- Islet Cell and Regenerative Biology, Joslin Diabetes CenterBostonUnited States
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUnited States
- Harvard Stem Cell Institute, Harvard Medical SchoolBostonUnited States
| | - Hyunki Kim
- Islet Cell and Regenerative Biology, Joslin Diabetes CenterBostonUnited States
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUnited States
- Harvard Stem Cell Institute, Harvard Medical SchoolBostonUnited States
| | - Jiang Hu
- Islet Cell and Regenerative Biology, Joslin Diabetes CenterBostonUnited States
| | - Debasish Manna
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and HarvardCambridgeUnited States
- Divisions of Renal Medicine and Engineering, Brigham and Women’s HospitalBostonUnited States
| | - Bridget Wagner
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and HarvardCambridgeUnited States
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and HarvardCambridgeUnited States
- Divisions of Renal Medicine and Engineering, Brigham and Women’s HospitalBostonUnited States
| | - Rohit N Kulkarni
- Islet Cell and Regenerative Biology, Joslin Diabetes CenterBostonUnited States
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUnited States
- Harvard Stem Cell Institute, Harvard Medical SchoolBostonUnited States
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46
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Vemana HP, Dukhande VV. The effect of hormones insulin and glucagon on ubiquitin modifications elucidated by proteomics in liver cells. Life Sci 2023; 329:121935. [PMID: 37442415 PMCID: PMC10528490 DOI: 10.1016/j.lfs.2023.121935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 07/02/2023] [Accepted: 07/10/2023] [Indexed: 07/15/2023]
Abstract
AIMS Insulin action is intertwined with changing levels of glucose and counter-regulatory hormone glucagon. While insulin lowers blood sugar level, glucagon raises it by promoting the breakdown of the stored glycogen in liver and releases glucose into the bloodstream. The hormones insulin and glucagon are key in the pathogenesis of type 2 diabetes (T2D). Insulin resistance is a primary predisposing factor for diabetes. Phosphorylation of insulin signaling molecules is altered in the insulin-resistant state. However, ubiquitin (Ub) modifications in insulin-resistant state are relatively understudied. To dissect the underlying mechanisms, we performed a proteomics study on hepatoma cells to study the regulation of ubiquitination by insulin and glucagon. MATERIALS AND METHODS We performed western blotting, immunoprecipitations, and affinity pull down using tandem Ub binding entities (TUBE) reagents on hepatoma cells treated with insulin or glucagon. Next, we performed MS/MS analysis on Ub-linkage specific affinity pull down samples. Gene ontology analysis and protein-protein interaction network analysis was performed using DAVID GO and STRING db, respectively. KEY FINDINGS The ubiquitination pattern of total Ub, K48-linked Ub, and K63-linked Ub was altered with the treatment of hormones insulin and glucagon. Ubiquitination in immunoprecipitated samples showed enrichment with total Ub and K48-linked Ub but not with K63-linked Ub. Ubiquitination by treatment with hormones mainly enriched key signaling pathways MAPK, Akt, oxidative stress etc. SIGNIFICANCE: Our study identified key altered proteins and signal transduction pathways which aids in understanding the mechanisms of hormonal action on ubiquitination and identify new therapeutic targets for T2D.
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Affiliation(s)
- Hari Priya Vemana
- Department of Pharmaceutical Sciences, College of Pharmacy & Health Sciences, St. John's University, Queens, NY 11439, USA
| | - Vikas V Dukhande
- Department of Pharmaceutical Sciences, College of Pharmacy & Health Sciences, St. John's University, Queens, NY 11439, USA.
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47
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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48
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Liu T, Khanal S, Hertslet GD, Lamichhane R. Single-molecule analysis reveals that a glucagon-bound extracellular domain of the glucagon receptor is dynamic. J Biol Chem 2023; 299:105160. [PMID: 37586587 PMCID: PMC10514447 DOI: 10.1016/j.jbc.2023.105160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 08/07/2023] [Accepted: 08/10/2023] [Indexed: 08/18/2023] Open
Abstract
Dynamic information is vital to understanding the activation mechanism of G protein-coupled receptors (GPCRs). Despite the availability of high-resolution structures of different conformational states, the dynamics of those states at the molecular level are poorly understood. Here, we used total internal reflection fluorescence microscopy to study the extracellular domain (ECD) of the glucagon receptor (GCGR), a class B family GPCR that controls glucose homeostasis. Single-molecule fluorescence resonance energy transfer was used to observe the ECD dynamics of GCGR molecules expressed and purified from mammalian cells. We observed that for apo-GCGR, the ECD is dynamic and spent time predominantly in a closed conformation. In the presence of glucagon, the ECD is wide open and also shows more dynamic behavior than apo-GCGR, a finding that was not previously reported. These results suggest that both apo-GCGR and glucagon-bound GCGRs show reversible opening and closing of the ECD with respect to the seven-transmembrane (7TM) domain. This work demonstrates a molecular approach to visualizing the dynamics of the GCGR ECD and provides a foundation for understanding the conformational changes underlying GPCR activation, which is critical in the development of new therapeutics.
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Affiliation(s)
- Ting Liu
- Department of Biochemistry & Cellular and Molecular Biology, College of Arts & Sciences, University of Tennessee, Knoxville, Tennessee, USA
| | - Susmita Khanal
- Department of Biochemistry & Cellular and Molecular Biology, College of Arts & Sciences, University of Tennessee, Knoxville, Tennessee, USA
| | - Gillian D Hertslet
- Department of Biochemistry & Cellular and Molecular Biology, College of Arts & Sciences, University of Tennessee, Knoxville, Tennessee, USA
| | - Rajan Lamichhane
- Department of Biochemistry & Cellular and Molecular Biology, College of Arts & Sciences, University of Tennessee, Knoxville, Tennessee, USA.
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49
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Insuela DBR, Ferrero MR, Chaves ADS, Coutinho DDS, Magalhães NDS, de Arantes ACS, Silva AR, Silva PMRE, Martins MA, Carvalho VF. Pro-resolving role of glucagon in lipopolysaccharide-induced mice lung neutrophilia. J Endocrinol 2023; 259:e220196. [PMID: 37552528 DOI: 10.1530/joe-22-0196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 08/08/2023] [Indexed: 08/09/2023]
Abstract
Prior research demonstrated that glucagon has protective roles against inflammation, but its effect on the resolution of inflammation remains elusive. Using in vitro and in vivo approaches, this study aimed to investigate the pro-resolving potential of glucagon on pulmonary neutrophilic inflammation caused by lipopolysaccharide. Lipopolysaccharide induced an increase in the proportions of neutrophils positives to glucagon receptor (GcgR) in vitro. In addition, lipopolysaccharide induced an increase in the neutrophil accumulation and expression of GcgR by the inflammatory cells in the lungs, however, without altering glucagon levels. Intranasal treatment with glucagon, at the peak of neutrophilic inflammation, reduced the neutrophil number in the bronchoalveolar lavage (BAL), and lung tissue within 24 h. The reduction of neutrophilic inflammation provoked by glucagon was accompanied by neutrophilia in the blood, an increase in the apoptosis rate of neutrophils in the BAL, enhance in the pro-apoptotic Bax protein expression, and decrease in the anti-apoptotic Bcl-2 protein levels in the lung. Glucagon also induced a rise in the cleavage of caspase-3 in the lungs; however, it was not significant. Glucagon inhibited the levels of IL-1β and TNF-α while increasing the content of pro-resolving mediators transforming growth factor (TGF-β1) and PGE2 in the BAL and lung. Finally, glucagon inhibited lipopolysaccharide-induced airway hyper-reactivity, as evidenced by the reduction in lung elastance values in response to methacholine. In conclusion, glucagon-induced resolution of neutrophilic inflammation by promoting cessation of neutrophil migration and a rise of neutrophil apoptosis and the levels of pro-resolving mediators TGF-β1 and PGE2.
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Affiliation(s)
| | - Maximiliano Ruben Ferrero
- Laboratório de Inflamação, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | - Amanda da Silva Chaves
- Laboratório de Inflamação, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | - Diego de Sá Coutinho
- Laboratório de Inflamação, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | - Nathalia Dos Santos Magalhães
- Laboratório de Pesquisa em Infecção Hospitalar, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | | | - Adriana Ribeiro Silva
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação (INCT-NIM), Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | | | - Marco Aurélio Martins
- Laboratório de Inflamação, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
| | - Vinicius Frias Carvalho
- Laboratório de Inflamação, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação (INCT-NIM), Fundação Oswaldo Cruz, Manguinhos, Rio de Janeiro, Brazil
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50
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Stefanakis K, Kokkinos A, Argyrakopoulou G, Konstantinidou SK, Simati S, Kouvari M, Kumar A, Kalra B, Kumar M, Bontozoglou N, Kyriakopoulou K, Mantzoros CS. Circulating levels of proglucagon-derived peptides are differentially regulated by the glucagon-like peptide-1 agonist liraglutide and the centrally acting naltrexone/bupropion and can predict future weight loss and metabolic improvements: A 6-month long interventional study. Diabetes Obes Metab 2023; 25:2561-2574. [PMID: 37246799 PMCID: PMC10524619 DOI: 10.1111/dom.15141] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/30/2023]
Abstract
AIM To investigate the changes of circulating levels of all proglucagon-derived peptides (PGDPs) in individuals with overweight or obesity receiving liraglutide (3 mg) or naltrexone/bupropion (32/360 mg), and to explore the association between induced changes in postprandial PGDP levels and body composition, as well as metabolic variables, after 3 and 6 months on treatment. MATERIALS AND METHODS Seventeen patients with obesity or with overweight and co-morbidities, but without diabetes, were assigned to receive once-daily oral naltrexone/bupropion 32/360 mg (n = 8) or once-daily subcutaneous liraglutide 3 mg (n = 9). Participants were assessed before treatment initiation and after 3 and 6 months on treatment. At the baseline and 3-month visits, participants underwent a 3-hour mixed meal tolerance test to measure fasting and postprandial levels of PGDPs, C-peptide, hunger and satiety. Clinical and biochemical indices of metabolic function, magnetic resonance-assessed liver steatosis and ultrasound-assessed liver stiffness were measured at each visit. RESULTS Both medications improved body weight and composition, carbohydrate and lipid metabolism, and liver fat and function. Naltrexone/bupropion produced a weight-independent increase in the levels of proglucagon (P < .001) and decreases in glucagon-like peptide-2 (GLP-2), glucagon and the major proglucagon fragment (P ≤ .01), whereas liraglutide markedly upregulated total glucagon-like peptide-1 (GLP-1) levels in a weight-independent manner (P = .04), and similarly downregulated the major proglucagon fragment, GLP-2 and glucagon (P < .01). PGDP levels at the 3-month visit were positively and independently correlated with improvements in fat mass, glycaemia, lipaemia and liver function, and negatively with reductions in fat-free mass, at both the 3- and 6-month visits. CONCLUSIONS PGDP levels in response to liraglutide and naltrexone/bupropion are associated with improvements in metabolism. Our study provides support for the administration of the downregulated members of the PGDP family as replacement therapy (e.g. glucagon), in addition to the medications currently in use that induced their downregulation (e.g. GLP-1), and future studies should explore whether the addition of other PGDPs (e.g. GLP-2) could offer additional benefits.
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Affiliation(s)
- Konstantinos Stefanakis
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Boston VA Healthcare System and Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
- First Department of Propaedeutic Internal Medicine, Laiko General Hospital, National and Kapodistrian University of Athens School of Medicine, Athens, Greece
| | - Alexander Kokkinos
- First Department of Propaedeutic Internal Medicine, Laiko General Hospital, National and Kapodistrian University of Athens School of Medicine, Athens, Greece
| | | | - Sofia K Konstantinidou
- First Department of Propaedeutic Internal Medicine, Laiko General Hospital, National and Kapodistrian University of Athens School of Medicine, Athens, Greece
- Diabetes and Obesity Unit, Athens Medical Center, Athens, Greece
| | - Stamatia Simati
- First Department of Propaedeutic Internal Medicine, Laiko General Hospital, National and Kapodistrian University of Athens School of Medicine, Athens, Greece
| | - Matina Kouvari
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Boston VA Healthcare System and Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | | | | | | | | | - Christos S Mantzoros
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Boston VA Healthcare System and Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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