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Opazo-Ríos L, Mas S, Marín-Royo G, Mezzano S, Gómez-Guerrero C, Moreno JA, Egido J. Lipotoxicity and Diabetic Nephropathy: Novel Mechanistic Insights and Therapeutic Opportunities. Int J Mol Sci 2020; 21:E2632. [PMID: 32290082 PMCID: PMC7177360 DOI: 10.3390/ijms21072632] [Citation(s) in RCA: 168] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 02/06/2023] Open
Abstract
Lipotoxicity is characterized by the ectopic accumulation of lipids in organs different from adipose tissue. Lipotoxicity is mainly associated with dysfunctional signaling and insulin resistance response in non-adipose tissue such as myocardium, pancreas, skeletal muscle, liver, and kidney. Serum lipid abnormalities and renal ectopic lipid accumulation have been associated with the development of kidney diseases, in particular diabetic nephropathy. Chronic hyperinsulinemia, often seen in type 2 diabetes, plays a crucial role in blood and liver lipid metabolism abnormalities, thus resulting in increased non-esterified fatty acids (NEFA). Excessive lipid accumulation alters cellular homeostasis and activates lipogenic and glycogenic cell-signaling pathways. Recent evidences indicate that both quantity and quality of lipids are involved in renal damage associated to lipotoxicity by activating inflammation, oxidative stress, mitochondrial dysfunction, and cell-death. The pathological effects of lipotoxicity have been observed in renal cells, thus promoting podocyte injury, tubular damage, mesangial proliferation, endothelial activation, and formation of macrophage-derived foam cells. Therefore, this review examines the recent preclinical and clinical research about the potentially harmful effects of lipids in the kidney, metabolic markers associated with these mechanisms, major signaling pathways affected, the causes of excessive lipid accumulation, and the types of lipids involved, as well as offers a comprehensive update of therapeutic strategies targeting lipotoxicity.
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Affiliation(s)
- Lucas Opazo-Ríos
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Sebastián Mas
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Gema Marín-Royo
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Sergio Mezzano
- Laboratorio de Nefrología, Facultad de Medicina, Universidad Austral de Chile, 5090000 Valdivia, Chile;
| | - Carmen Gómez-Guerrero
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
| | - Juan Antonio Moreno
- Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), University of Cordoba, 14004 Cordoba, Spain
- Hospital Universitario Reina Sofía, 14004 Cordoba, Spain
| | - Jesús Egido
- Renal, Vascular and Diabetes Research Laboratory, IIS-Fundación Jiménez Díaz, Universidad Autónoma de Madrid, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), 28040 Madrid, Spain; (L.O.-R.); (G.M.-R.); (C.G.-G.); (J.E.)
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Blumer I, Novak LM, Edelman S, Cavaiola TS. Transitioning to Fixed-Ratio Combination Therapy: Five Frequently Asked Questions Health Care Providers Should Anticipate From Their Patients. Clin Diabetes 2019; 37:386-390. [PMID: 31660014 PMCID: PMC6794219 DOI: 10.2337/cd18-0102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Ian Blumer
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Charles H. Best Diabetes Centre, Ajax, Ontario, Canada
| | | | - Steven Edelman
- Veterans Affairs Medical Center, University of California San Diego, San Diego, CA
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Zhou P, Santoro A, Peroni OD, Nelson AT, Saghatelian A, Siegel D, Kahn BB. PAHSAs enhance hepatic and systemic insulin sensitivity through direct and indirect mechanisms. J Clin Invest 2019; 129:4138-4150. [PMID: 31449056 PMCID: PMC6763232 DOI: 10.1172/jci127092] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 06/24/2019] [Indexed: 12/30/2022] Open
Abstract
Palmitic acid esters of hydroxy stearic acids (PAHSAs) are bioactive lipids with antiinflammatory and antidiabetic effects. PAHSAs reduce ambient glycemia and improve glucose tolerance and insulin sensitivity in insulin-resistant aged chow- and high-fat diet-fed (HFD-fed) mice. Here, we aimed to determine the mechanisms by which PAHSAs improve insulin sensitivity. Both acute and chronic PAHSA treatment enhanced the action of insulin to suppress endogenous glucose production (EGP) in chow- and HFD-fed mice. Moreover, chronic PAHSA treatment augmented insulin-stimulated glucose uptake in glycolytic muscle and heart in HFD-fed mice. The mechanisms by which PAHSAs enhanced hepatic insulin sensitivity included direct and indirect actions involving intertissue communication between adipose tissue and liver. PAHSAs inhibited lipolysis directly in WAT explants and enhanced the action of insulin to suppress lipolysis during the clamp in vivo. Preventing the reduction of free fatty acids during the clamp with Intralipid infusion reduced PAHSAs' effects on EGP in HFD-fed mice but not in chow-fed mice. Direct hepatic actions of PAHSAs may also be important, as PAHSAs inhibited basal and glucagon-stimulated EGP directly in isolated hepatocytes through a cAMP-dependent pathway involving Gαi protein-coupled receptors. Thus, this study advances our understanding of PAHSA biology and the physiologic mechanisms by which PAHSAs exert beneficial metabolic effects.
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Affiliation(s)
- Peng Zhou
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Anna Santoro
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Odile D. Peroni
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| | - Andrew T. Nelson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, UCSD, La Jolla, California, USA
| | - Alan Saghatelian
- Clayton Foundation Laboratories for Peptide Biology, Helmsley Center for Genomic Medicine, Salk Institute for Biological Studies, La Jolla, California, USA
| | - Dionicio Siegel
- Skaggs School of Pharmacy and Pharmaceutical Sciences, UCSD, La Jolla, California, USA
| | - Barbara B. Kahn
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
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Abstract
PURPOSE OF REVIEW The purpose of this review is to provide a brief summary of recent advances in our understanding of liver metabolism. The critical role of the liver in controlling whole-body energy homeostasis makes such understanding crucial to efficiently design new treatments for metabolic syndrome diseases, including type 2 diabetes (T2D). RECENT FINDINGS Significant advances have been made regarding our understanding of the direct and indirect effects of insulin on hepatic metabolism and the communication between the liver and other tissues. Moreover, the catabolic functions of glucagon, as well as the importance of hepatic redox status for the regulation of glucose production, are emerging as potential targets to reduce hyperglycemia. A resolution to the long-standing question "insulin suppression of hepatic glucose production, direct or indirect effect?" is starting to emerge. New advances in our understanding of important fasting-induced hepatic metabolic fluxes may help design better therapies for T2D.
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Affiliation(s)
- Kfir Sharabi
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Cell Biology, Harvard Medical School, 450 Brookline Av. LC-6219H, Boston, MA, 02215, USA.
| | - Clint D J Tavares
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Cell Biology, Harvard Medical School, 450 Brookline Av. LC-6219H, Boston, MA, 02215, USA
| | - Pere Puigserver
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Cell Biology, Harvard Medical School, 450 Brookline Av. LC-6219H, Boston, MA, 02215, USA.
- Dana-Farber Cancer Institute, 450 Brookline Av. LC-6213, Boston, MA, 02215, USA.
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Khan RMM, Chua ZJY, Tan JC, Yang Y, Liao Z, Zhao Y. From Pre-Diabetes to Diabetes: Diagnosis, Treatments and Translational Research. MEDICINA (KAUNAS, LITHUANIA) 2019; 55:E546. [PMID: 31470636 PMCID: PMC6780236 DOI: 10.3390/medicina55090546] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 08/16/2019] [Accepted: 08/23/2019] [Indexed: 12/14/2022]
Abstract
Diabetes, a silent killer, is one of the most widely prevalent conditions of the present time. According to the 2017 International Diabetes Federation (IDF) statistics, the global prevalence of diabetes among the age group of 20-79 years is 8.8%. In addition, 1 in every 2 persons is unaware of the condition. This unawareness and ignorance lead to further complications. Pre-diabetes is the preceding condition of diabetes, and in most of the cases, this ultimately leads to the development of diabetes. Diabetes can be classified into three types, namely type 1 diabetes, type 2 diabetes mellitus (T2DM) and gestational diabetes. The diagnosis of both pre-diabetes and diabetes is based on glucose criteria; the common modalities used are fasting plasma glucose (FPG) test and oral glucose tolerance test (OGTT). A glucometer is commonly used by diabetic patients to measure blood glucose levels with fast and rather accurate measurements. A few of the more advanced and minimally invasive modalities include the glucose-sensing patch, SwEatch, eyeglass biosensor, breath analysis, etc. Despite a considerable amount of data being collected and analyzed regarding diabetes, the actual molecular mechanism of developing type 2 diabetes mellitus (T2DM) is still unknown. Both genetic and epigenetic factors are associated with T2DM. The complications of diabetes can predominantly be classified into two categories: microvascular and macrovascular. Retinopathy, nephropathy, and neuropathy are grouped under microvascular complications, whereas stroke, cardiovascular disease, and peripheral artery disease (PAD) belong to macrovascular complications. Unfortunately, until now, no complete cure for diabetes has been found. However, the treatment of pre-diabetes has shown significant success in preventing the further progression of diabetes. To prevent pre-diabetes from developing into T2DM, lifestyle intervention has been found to be very promising. Various aspects of diabetes, including the aforementioned topics, have been reviewed in this paper.
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Affiliation(s)
- Radia Marium Modhumi Khan
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore
| | - Zoey Jia Yu Chua
- School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore
| | - Jia Chi Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
| | - Yingying Yang
- Tongji University School of Medicine, Shanghai 201204, China
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 171 65 Solna, Sweden
| | - Zehuan Liao
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
- Department of Microbiology, Tumor, and Cell Biology (MTC), Karolinska Institutet, Biomedicum, Solnavägen 9, SE-17177 Stockholm, Sweden.
| | - Yan Zhao
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
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56
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Abstract
PURPOSE OF REVIEW Increased glucose production associated with hepatic insulin resistance contributes to the development of hyperglycemia in T2D. The molecular mechanisms accounting for increased glucose production remain controversial. Our aims were to review recent literature concerning molecular mechanisms regulating glucose production and to discuss these mechanisms in the context of physiological experiments and observations in humans and large animal models. RECENT FINDINGS Genetic intervention studies in rodents demonstrate that insulin can control hepatic glucose production through both direct effects on the liver, and through indirect effects to inhibit adipose tissue lipolysis and limit gluconeogenic substrate delivery. However, recent experiments in canine models indicate that the direct effects of insulin on the liver are dominant over the indirect effects to regulate glucose production. Recent molecular studies have also identified insulin-independent mechanisms by which hepatocytes sense intrahepatic carbohydrate levels to regulate carbohydrate disposal. Dysregulation of hepatic carbohydrate sensing systems may participate in increased glucose production in the development of diabetes.
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Affiliation(s)
- Ashot Sargsyan
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
| | - Mark A Herman
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA.
- Division of Diabetes, Endocrinology, and Metabolism, Duke University, Durham, NC, USA.
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Staniek H. The Combined Effects of Cr(III) Supplementation and Iron Deficiency on the Copper and Zinc Status in Wistar Rats. Biol Trace Elem Res 2019; 190:414-424. [PMID: 30430418 PMCID: PMC6599762 DOI: 10.1007/s12011-018-1568-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/05/2018] [Indexed: 01/08/2023]
Abstract
The aim of the study was to assess the combined effects of chromium(III) supplementation and iron deficiency on the copper (Cu) and zinc (Zn) status in female rats. The Cr, Fe, Cu and Zn dietary and tissular levels were measured by Atomic Absorption Spectrometry (AAS) method. The data show that chromium(III) supplementation compensated for the negative effects of Fe deficiency on the Cu content but it deepened the effect on Zn levels in the female rats. Detailed data on the status of trace elements and their interactions in healthy subjects and patients with metabolic disorders (e.g. anaemia, diabetes mellitus) are strongly required for effective nutritional and therapeutic strategies.
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Affiliation(s)
- Halina Staniek
- Institute of Human Nutrition and Dietetics, Poznań University of Life Sciences, ul. Wojska Polskiego 31, 60-624, Poznań, Poland.
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Molinaro A, Becattini B, Mazzoli A, Bleve A, Radici L, Maxvall I, Sopasakis VR, Molinaro A, Bäckhed F, Solinas G. Insulin-Driven PI3K-AKT Signaling in the Hepatocyte Is Mediated by Redundant PI3Kα and PI3Kβ Activities and Is Promoted by RAS. Cell Metab 2019; 29:1400-1409.e5. [PMID: 30982732 DOI: 10.1016/j.cmet.2019.03.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 02/04/2019] [Accepted: 03/19/2019] [Indexed: 12/17/2022]
Abstract
Phosphatidylinositol-3-kinase (PI3K) activity is aberrant in tumors, and PI3K inhibitors are investigated as cancer therapeutics. PI3K signaling mediates insulin action in metabolism, but the role of PI3K isoforms in insulin signaling remains unresolved. Defining the role of PI3K isoforms in insulin signaling is necessary for a mechanistic understanding of insulin action and to develop PI3K inhibitors with optimal therapeutic index. We show that insulin-driven PI3K-AKT signaling depends on redundant PI3Kα and PI3Kβ activities, whereas PI3Kδ and PI3Kγ are largely dispensable. We have also found that RAS activity promotes AKT phosphorylation in insulin-stimulated hepatocytes and that promotion of insulin-driven AKT phosphorylation by RAS depends on PI3Kα. These findings reveal the detailed mechanism by which insulin activates AKT, providing an improved mechanistic understanding of insulin signaling. This improved model for insulin signaling predicts that isoform-selective PI3K inhibitors discriminating between PI3Kα and PI3Kβ should be dosed below their hyperglycemic threshold to achieve isoform selectivity.
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Affiliation(s)
- Angela Molinaro
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Barbara Becattini
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Arianna Mazzoli
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Augusto Bleve
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Lucia Radici
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Ingela Maxvall
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Victoria Rotter Sopasakis
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Antonio Molinaro
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Fredrik Bäckhed
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden; Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Metabolic Receptology and Enteroendocrinology, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Giovanni Solinas
- The Wallenberg Laboratory and Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.
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Nagarajan SR, Paul-Heng M, Krycer JR, Fazakerley DJ, Sharland AF, Hoy AJ. Lipid and glucose metabolism in hepatocyte cell lines and primary mouse hepatocytes: a comprehensive resource for in vitro studies of hepatic metabolism. Am J Physiol Endocrinol Metab 2019; 316:E578-E589. [PMID: 30694691 DOI: 10.1152/ajpendo.00365.2018] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The liver is a critical tissue for maintaining glucose, fatty acid, and cholesterol homeostasis. Primary hepatocytes represent the gold standard for studying the mechanisms controlling hepatic glucose, lipid, and cholesterol metabolism in vitro. However, access to primary hepatocytes can be limiting, and therefore, other immortalized hepatocyte models are commonly used. Here, we describe substrate metabolism of cultured AML12, IHH, and PH5CH8 cells, hepatocellular carcinoma-derived HepG2s, and primary mouse hepatocytes (PMH) to identify which of these cell lines most accurately phenocopy PMH basal and insulin-stimulated metabolism. Insulin-stimulated glucose metabolism in PH5CH8 cells, and to a lesser extent AML12 cells, responded most similarly to PMH. Notably, glucose incorporation in HepG2 cells were 14-fold greater than PMH. The differences in glucose metabolic activity were not explained by differential protein expression of key regulators of these pathways, for example glycogen synthase and glycogen content. In contrast, fatty acid metabolism in IHH cells was the closest to PMHs, yet insulin-responsive fatty acid metabolism in AML12 and HepG2 cells was most similar to PMH. Finally, incorporation of acetate into intracellular-free cholesterol was comparable for all cells to PMH; however, insulin-stimulated glucose conversion into lipids and the incorporation of acetate into intracellular cholesterol esters were strikingly different between PMHs and all tested cell lines. In general, AML12 cells most closely phenocopied PMH in vitro energy metabolism. However, the cell line most representative of PMHs differed depending on the mode of metabolism being investigated, and so careful consideration is needed in model selection.
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Affiliation(s)
- Shilpa R Nagarajan
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney , New South Wales , Australia
| | - Moumita Paul-Heng
- Discipline of Surgery, Central Clinical School & Bosch Institute, Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney , New South Wales , Australia
| | - James R Krycer
- School of Life and Environmental Sciences, Charles Perkins Centre, Faculty of Science, The University of Sydney , New South Wales , Australia
| | - Daniel J Fazakerley
- School of Life and Environmental Sciences, Charles Perkins Centre, Faculty of Science, The University of Sydney , New South Wales , Australia
| | - Alexandra F Sharland
- Discipline of Surgery, Central Clinical School & Bosch Institute, Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney , New South Wales , Australia
| | - Andrew J Hoy
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, Faculty of Medicine and Health, The University of Sydney , New South Wales , Australia
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Ehrhardt N, Cui J, Dagdeviren S, Saengnipanthkul S, Goodridge HS, Kim JK, Lantier L, Guo X, Chen YDI, Raffel LJ, Buchanan TA, Hsueh WA, Rotter JI, Goodarzi MO, Péterfy M. Adiposity-Independent Effects of Aging on Insulin Sensitivity and Clearance in Mice and Humans. Obesity (Silver Spring) 2019; 27:434-443. [PMID: 30801985 PMCID: PMC6474357 DOI: 10.1002/oby.22418] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 11/21/2018] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Aging is associated with impaired insulin sensitivity and increased prevalence of type 2 diabetes. However, it remains unclear whether aging-associated insulin resistance is due to increased adiposity or other age-related factors. To address this question, the impact of aging on insulin sensitivity was investigated independently of changes in body composition. METHODS Cohorts of mice aged 4 to 8 months ("young") and 18 to 27 months ("aged") exhibiting similar body composition were characterized for glucose metabolism on chow and high-fat diets. Insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamp analyses. The relationship between aging and insulin resistance in humans was investigated in 1,250 nondiabetic Mexican Americans who underwent hyperinsulinemic-euglycemic clamps. RESULTS In mice with similar body composition, age had no detrimental effect on plasma glucose and insulin levels. While aging did not diminish glucose tolerance, hyperinsulinemic-euglycemic clamps demonstrated impaired insulin sensitivity and reduced insulin clearance in aged mice on chow and high-fat diets. Consistent with results in the mouse, age remained an independent determinant of insulin resistance after adjustment for body composition in Mexican American males. CONCLUSIONS This study demonstrates that in addition to altered body composition, adiposity-independent mechanisms also contribute to aging-associated insulin resistance in mice and humans.
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Affiliation(s)
- Nicole Ehrhardt
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Jinrui Cui
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Sezin Dagdeviren
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Suchaorn Saengnipanthkul
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Helen S. Goodridge
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Jason K. Kim
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
- Division of Endocrinology, Metabolism, and Diabetes, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Louise Lantier
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37235, USA
| | - Xiuqing Guo
- Institute for Translational Genomics and Population Sciences, Los Angeles BioMedical Research Institute and Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Yii-Der I. Chen
- Institute for Translational Genomics and Population Sciences, Los Angeles BioMedical Research Institute and Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Leslie J. Raffel
- Department of Pediatrics, Division of Genetic and Genomic Medicine, University of California, Irvine, CA 92697, USA
| | - Thomas A. Buchanan
- Department of Physiology and Biophysics and Department of Medicine, Keck School of Medicine of USC, Los Angeles, CA 90033, USA
| | - Willa A. Hsueh
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Jerome I. Rotter
- Institute for Translational Genomics and Population Sciences, Los Angeles BioMedical Research Institute and Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Mark O. Goodarzi
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
- Corresponding authors: Mark O. Goodarzi () and Miklós Péterfy () Tel: +1 909 706 3949
| | - Miklós Péterfy
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
- Corresponding authors: Mark O. Goodarzi () and Miklós Péterfy () Tel: +1 909 706 3949
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Voss TS, Vendelbo MH, Kampmann U, Pedersen SB, Nielsen TS, Johannsen M, Svart MV, Jessen N, Møller N. Substrate metabolism, hormone and cytokine levels and adipose tissue signalling in individuals with type 1 diabetes after insulin withdrawal and subsequent insulin therapy to model the initiating steps of ketoacidosis. Diabetologia 2019; 62:494-503. [PMID: 30506451 DOI: 10.1007/s00125-018-4785-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 10/18/2018] [Indexed: 12/31/2022]
Abstract
AIMS/HYPOTHESIS Lack of insulin and infection/inflammation are the two most common causes of diabetic ketoacidosis (DKA). We used insulin withdrawal followed by insulin administration as a clinical model to define effects on substrate metabolism and to test whether increased levels of counter-regulatory hormones and cytokines and altered adipose tissue signalling participate in the early phases of DKA. METHODS Nine individuals with type 1 diabetes, without complications, were randomly studied twice, in a crossover design, for 5 h followed by 2.5 h high-dose insulin clamp: (1) insulin-controlled euglycaemia (control) and (2) after 14 h of insulin withdrawal in a university hospital setting. RESULTS Insulin withdrawal increased levels of glucose (6.1 ± 0.5 vs 18.6 ± 0.5 mmol/l), NEFA, 3-OHB (127 ± 18 vs 1837 ± 298 μmol/l), glucagon, cortisol and growth hormone and decreased HCO3- and pH, without affecting catecholamine or cytokine levels. Whole-body energy expenditure, endogenous glucose production (1.55 ± 0.13 vs 2.70 ± 0.31 mg kg-1 min-1), glucose turnover, non-oxidative glucose disposal, lipid oxidation, palmitate flux (73 [range 39-104] vs 239 [151-474] μmol/min), protein oxidation and phenylalanine flux all increased, whereas glucose oxidation decreased. In adipose tissue, Ser473 phosphorylation of Akt and mRNA levels of G0S2 decreased, whereas CGI-58 (also known as ABHD5) mRNA increased. Protein levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase phosphorylations were unaltered. Insulin therapy decreased plasma glucose concentrations dramatically after insulin withdrawal, without any detectable effect on net forearm glucose uptake. CONCLUSIONS/INTERPRETATION Release of counter-regulatory hormones and overall increased catabolism, including lipolysis, are prominent features of preacidotic ketosis induced by insulin withdrawal, and dampening of Akt insulin signalling and transcriptional modulation of ATGL activity are involved. The lack of any increase in net forearm glucose uptake during insulin therapy after insulin withdrawal indicates muscle insulin resistance. TRIAL REGISTRATION ClinicalTrials.gov NCT02077348 FUNDING: This study was supported by Aarhus University and the KETO Study Group/Danish Agency for Science Technology and Innovation.
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Affiliation(s)
- Thomas S Voss
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44, building 3, DK-8000, Aarhus C, Denmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Mikkel H Vendelbo
- Department of Nuclear Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Ulla Kampmann
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Steen B Pedersen
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Thomas S Nielsen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section on Integrative Physiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mogens Johannsen
- Section for Forensic Chemistry, Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
| | - Mads V Svart
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44, building 3, DK-8000, Aarhus C, Denmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Niels Jessen
- Research Laboratory for Biochemical Pathology and Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark
| | - Niels Møller
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44, building 3, DK-8000, Aarhus C, Denmark.
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark.
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Edgerton DS, Scott M, Farmer B, Williams PE, Madsen P, Kjeldsen T, Brand CL, Fledelius C, Nishimura E, Cherrington AD. Targeting insulin to the liver corrects defects in glucose metabolism caused by peripheral insulin delivery. JCI Insight 2019; 5:126974. [PMID: 30830873 DOI: 10.1172/jci.insight.126974] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Peripheral hyperinsulinemia resulting from subcutaneous insulin injection is associated with metabolic defects which include abnormal glucose metabolism. The first aim of this study was to quantify the impairments in liver and muscle glucose metabolism that occur when insulin is delivered via a peripheral vein compared to when it is given through its endogenous secretory route (the hepatic portal vein) in overnight fasted conscious dogs. The second aim was to determine if peripheral delivery of a hepato-preferential insulin analog could restore the physiologic response to insulin that occurs under meal feeding conditions. This study is the first to show that hepatic glucose uptake correlates with insulin's direct effects on the liver under hyperinsulinemic-hyperglycemic conditions. In addition, glucose uptake was equally divided between the liver and muscle when insulin was infused into the portal vein, but when it was delivered into a peripheral vein the percentage of glucose taken up by muscle was 4-times greater than that going to the liver, with liver glucose uptake being less than half of normal. These defects could not be corrected by adjusting the dose of peripheral insulin. On the other hand, hepatic and non-hepatic glucose metabolism could be fully normalized by a hepato-preferential insulin analog.
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Affiliation(s)
- Dale S Edgerton
- Vanderbilt University School of Medicine, Department of Molecular Physiology and Biophysics, Nashville, Tennessee, USA
| | - Melanie Scott
- Vanderbilt University School of Medicine, Department of Molecular Physiology and Biophysics, Nashville, Tennessee, USA
| | - Ben Farmer
- Vanderbilt University School of Medicine, Department of Molecular Physiology and Biophysics, Nashville, Tennessee, USA
| | - Phillip E Williams
- Vanderbilt University Medical Center, Division of Surgical Research, Nashville, Tennessee, USA
| | - Peter Madsen
- Research and Development, Novo Nordisk A/S, Novo Nordisk Park, Maaleov, Denmark
| | - Thomas Kjeldsen
- Research and Development, Novo Nordisk A/S, Novo Nordisk Park, Maaleov, Denmark
| | - Christian L Brand
- Research and Development, Novo Nordisk A/S, Novo Nordisk Park, Maaleov, Denmark
| | - Christian Fledelius
- Research and Development, Novo Nordisk A/S, Novo Nordisk Park, Maaleov, Denmark
| | - Erica Nishimura
- Research and Development, Novo Nordisk A/S, Novo Nordisk Park, Maaleov, Denmark
| | - Alan D Cherrington
- Vanderbilt University School of Medicine, Department of Molecular Physiology and Biophysics, Nashville, Tennessee, USA
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Santoleri D, Titchenell PM. Resolving the Paradox of Hepatic Insulin Resistance. Cell Mol Gastroenterol Hepatol 2018; 7:447-456. [PMID: 30739869 PMCID: PMC6369222 DOI: 10.1016/j.jcmgh.2018.10.016] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/30/2018] [Accepted: 10/30/2018] [Indexed: 12/12/2022]
Abstract
Insulin resistance is associated with numerous metabolic disorders, such as obesity and type II diabetes, that currently plague our society. Although insulin normally promotes anabolic metabolism in the liver by increasing glucose consumption and lipid synthesis, insulin-resistant individuals fail to inhibit hepatic glucose production and paradoxically have increased liver lipid synthesis, leading to hyperglycemia and hypertriglyceridemia. Here, we detail the intrahepatic and extrahepatic pathways mediating insulin's control of glucose and lipid metabolism. We propose that the interplay between both of these pathways controls insulin signaling and that mis-regulation between the 2 results in the paradoxic effects seen in the insulin-resistant liver instead of the commonly proposed deficiencies in particular branches of only the direct hepatic pathway.
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Affiliation(s)
- Dominic Santoleri
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Paul M. Titchenell
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania,Correspondence Address correspondence to: Paul M. Titchenell, PhD, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Boulevard, Philadelphia, Pennsylvania 19104. fax: (215) 898-5408.
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64
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Kutoh E, Wada A, Hayashi J. REGULATION OF FREE FATTY ACID BY SITAGLIPTIN MONOTHERAPY IN DRUG-NAÏVE SUBJECTS WITH TYPE 2 DIABETES. Endocr Pract 2018; 24:1063-1072. [PMID: 30289315 DOI: 10.4158/ep-2018-0287] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the effects of sitagliptin on the regulation of free fatty acid (FFA) and other metabolic parameters in drug-naïve subjects with type 2 diabetes mellitus (T2DM). METHODS This was a prospective, nonrandomized, observational study. Drug-naïve subjects with T2DM received 25 to 50 mg/day sitagliptin monotherapy (n = 64). At 3 months, FFA and other metabolic parameters were compared with those at baseline. FFA was measured by colorimetry with enzymatic reactions. As a comparator, 12.5 to 25 mg/day alogliptin monotherapy was given to drug-naïve subjects with T2DM (n = 55). RESULTS Significant reductions in FFA (-13.2%, P<0.01) levels were observed with sitagliptin but not alogliptin. Both drugs showed similar glycemic efficacies. Significant correlations were observed between the changes (Δ) of FFA and Δglycated hemoglobin A1c (HbA1c), Dtotal cholesterol (TC), Δnon-high-density lipoprotein cholesterol (HDL-C), or Δlow-density lipoprotein cholesterol (LDL-C), and significant negative correlations were seen between ΔFFA and Δhomeostasis model assessment-B (HOMA-B), ΔC-peptide immunoreactivity (CPR)-index or Δbody mass index (BMI) in the sitagliptin group. The subjects in the sitagliptin group were further divided into 2 subgroups (n = 32 each) according to the changes of FFA (group B [above the median] ΔFFA = 23.1 %, P<.0005; group A [below the median] ΔFFA = -37.3 %, P<.00001). At baseline, FFA levels were significantly higher in group A versus group B ( P<.001). Higher degrees of reductions of FBG (-14.6% vs. -9.3%, P<0.05) or HbA1c (-20.6% vs. -16.9%, P<.05), and increases of HOMA-B (52.7% vs. 38.3%, P<.03) or CPR-index (37.5% vs. 18.8%, P<.02) were observed in group A versus group B. Significant reductions of TC (-5.8%, P<.002), non-HDL-C (-7.8%, P<.001) or LDL-C (-6.3%, P<.02), and significant increases of C-peptide (11.3%, P<.05) were seen only in group A. CONCLUSION Sitagliptin could downregulate high FFA levels. Subjects with reductions of FFA levels had better glycemic efficacies and higher degrees of enhancement of beta-cell function than others. Reductions of atherogenic cholesterols were seen in these populations. ABBREVIATIONS CPR = C-peptide immunoreactivity; DPP-4 = dipeptidyl peptidase 4; FBG = fasting blood glucose; FFA = free fatty acid; HbA1c = glycated hemoglobin A1c; HDL-C = high-density lipoprotein cholesterol; HOMA-R = homeostasis model assessment-R; HOMA-B = homeostasis model assessment-B; non-HDL-C = non-HDL-cholesterol; LDL-C = low-density lipoprotein cholesterol; TC = total cholesterol; T2DM = type 2 diabetes; TG = triglyceride; UA = uric acid.
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Moore MC, Smith MS, Farmer B, Coate KC, Kraft G, Shiota M, Williams PE, Cherrington AD. Morning Hyperinsulinemia Primes the Liver for Glucose Uptake and Glycogen Storage Later in the Day. Diabetes 2018; 67:1237-1245. [PMID: 29666062 PMCID: PMC6014555 DOI: 10.2337/db17-0979] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 04/10/2018] [Indexed: 12/13/2022]
Abstract
We observed that a 4-h morning (AM) duodenal infusion of glucose versus saline doubled hepatic glucose uptake (HGU) and storage during a hyperinsulinemic-hyperglycemic (HIHG) clamp that afternoon (PM). To separate the effects of AM hyperglycemia versus AM hyperinsulinemia on the PM response, we used hepatic balance and tracer ([3-3H]glucose) techniques in conscious dogs. From 0 to 240 min, dogs underwent a euinsulinemic-hyperglycemic (GLC; n = 7) or hyperinsulinemic-euglycemic (INS; n = 8) clamp. Tracer equilibration and basal sampling occurred from 240 to 360 min, followed by an HIHG clamp (360-600 min; four times basal insulin, two times basal glycemia) with portal glucose infusion (4 mg ⋅ kg-1 ⋅ min-1). In the HIHG clamp, HGU (5.8 ± 0.9 vs. 3.3 ± 0.3 mg ⋅ kg-1 ⋅ min-1) and net glycogen storage (6.0 ± 0.8 vs. 2.9 ± 0.5 mg ⋅ kg-1 ⋅ min-1) were approximately twofold greater in INS than in GLC. PM hepatic glycogen content (1.9 ± 0.2 vs. 1.3 ± 0.2 g/kg body weight) and glycogen synthase (GS) activity were also greater in INS versus GLC, whereas glycogen phosphorylase (GP) activity was reduced. Thus AM hyperinsulinemia, but not AM hyperglycemia, enhanced the HGU response to a PM HIHG clamp by augmenting GS and reducing GP activity. AM hyperinsulinemia can prime the liver to extract and store glucose more effectively during subsequent same-day meals, potentially providing a tool to improve glucose control.
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Affiliation(s)
- Mary Courtney Moore
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
- Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN
| | - Marta S Smith
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Ben Farmer
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
- Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN
| | - Katie C Coate
- Department of Nutrition and Dietetics, Samford University, Birmingham, AL
| | - Guillaume Kraft
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Masakazu Shiota
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
- Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN
| | - Phillip E Williams
- Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN
- Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN
| | - Alan D Cherrington
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
- Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN
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Tao R, Wang C, Stöhr O, Qiu W, Hu Y, Miao J, Dong XC, Leng S, Stefater M, Stylopoulos N, Lin L, Copps KD, White MF. Inactivating hepatic follistatin alleviates hyperglycemia. Nat Med 2018; 24:1058-1069. [PMID: 29867232 PMCID: PMC6039237 DOI: 10.1038/s41591-018-0048-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 04/10/2018] [Indexed: 12/16/2022]
Abstract
Unsuppressed hepatic glucose production (HGP) contributes substantially to glucose intolerance and diabetes, which can be modeled by the genetic inactivation of hepatic insulin receptor substrate 1 (Irs1) and Irs2 (LDKO mice). We previously showed that glucose intolerance in LDKO mice is resolved by hepatic inactivation of the transcription factor FoxO1 (that is, LTKO mice)-even though the liver remains insensitive to insulin. Here, we report that insulin sensitivity in the white adipose tissue of LDKO mice is also impaired but is restored in LTKO mice in conjunction with normal suppression of HGP by insulin. To establish the mechanism by which white adipose tissue insulin signaling and HGP was regulated by hepatic FoxO1, we identified putative hepatokines-including excess follistatin (Fst)-that were dysregulated in LDKO mice but normalized in LTKO mice. Knockdown of hepatic Fst in the LDKO mouse liver restored glucose tolerance, white adipose tissue insulin signaling and the suppression of HGP by insulin; however, the expression of Fst in the liver of healthy LTKO mice had the opposite effect. Of potential clinical significance, knockdown of Fst also improved glucose tolerance in high-fat-fed obese mice, and the level of serum Fst was reduced in parallel with glycated hemoglobin in obese individuals with diabetes who underwent therapeutic gastric bypass surgery. We conclude that Fst is a pathological hepatokine that might be targeted for diabetes therapy during hepatic insulin resistance.
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Affiliation(s)
- Rongya Tao
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Caixia Wang
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Oliver Stöhr
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Wei Qiu
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yue Hu
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ji Miao
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - X Charlie Dong
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Sining Leng
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Margaret Stefater
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Nicholas Stylopoulos
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lin Lin
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kyle D Copps
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Morris F White
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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Harvey I, Stephenson EJ, Redd JR, Tran QT, Hochberg I, Qi N, Bridges D. Glucocorticoid-Induced Metabolic Disturbances Are Exacerbated in Obese Male Mice. Endocrinology 2018; 159:2275-2287. [PMID: 29659785 PMCID: PMC5946848 DOI: 10.1210/en.2018-00147] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/05/2018] [Indexed: 12/16/2022]
Abstract
The purpose of this study was to determine the effects of glucocorticoid-induced metabolic dysfunction in the presence of diet-induced obesity. C57BL/6J adult male lean and diet-induced obese mice were given dexamethasone, and levels of hepatic steatosis, insulin resistance, and lipolysis were determined. Obese mice given dexamethasone had significant, synergistic effects on fasting glucose, insulin resistance, and markers of lipolysis, as well as hepatic steatosis. This was associated with synergistic transactivation of the lipolytic enzyme adipose triglyceride lipase. The combination of chronically elevated glucocorticoids and obesity leads to exacerbations in metabolic dysfunction. Our findings suggest lipolysis may be a key player in glucocorticoid-induced insulin resistance and fatty liver in individuals with obesity.
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Affiliation(s)
- Innocence Harvey
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Erin J Stephenson
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - JeAnna R Redd
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Quynh T Tran
- Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Irit Hochberg
- Institute of Endocrinology, Diabetes and Metabolism, Rambam Health Care Campus, Haifa, Israel
| | - Nathan Qi
- Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, Michigan
| | - Dave Bridges
- Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, Michigan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
- Correspondence: Dave Bridges, PhD, Department of Nutritional Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, Michigan 48109. E-mail:
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Corbit KC, Camporez JPG, Edmunds LR, Tran JL, Vera NB, Erion DM, Deo RC, Perry RJ, Shulman GI, Jurczak MJ, Weiss EJ. Adipocyte JAK2 Regulates Hepatic Insulin Sensitivity Independently of Body Composition, Liver Lipid Content, and Hepatic Insulin Signaling. Diabetes 2018; 67:208-221. [PMID: 29203511 PMCID: PMC5780061 DOI: 10.2337/db17-0524] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 11/15/2017] [Indexed: 01/07/2023]
Abstract
Disruption of hepatocyte growth hormone (GH) signaling through disruption of Jak2 (JAK2L) leads to fatty liver. Previously, we demonstrated that development of fatty liver depends on adipocyte GH signaling. We sought to determine the individual roles of hepatocyte and adipocyte Jak2 on whole-body and tissue insulin sensitivity and liver metabolism. On chow, JAK2L mice had hepatic steatosis and severe whole-body and hepatic insulin resistance. However, concomitant deletion of Jak2 in hepatocytes and adipocytes (JAK2LA) completely normalized insulin sensitivity while reducing liver lipid content. On high-fat diet, JAK2L mice had hepatic steatosis and insulin resistance despite protection from diet-induced obesity. JAK2LA mice had higher liver lipid content and no protection from obesity but retained exquisite hepatic insulin sensitivity. AKT activity was selectively attenuated in JAK2L adipose tissue, whereas hepatic insulin signaling remained intact despite profound hepatic insulin resistance. Therefore, JAK2 in adipose tissue is epistatic to liver with regard to insulin sensitivity and responsiveness, despite fatty liver and obesity. However, hepatocyte autonomous JAK2 signaling regulates liver lipid deposition under conditions of excess dietary fat. This work demonstrates how various tissues integrate JAK2 signals to regulate insulin/glucose and lipid metabolism.
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Affiliation(s)
- Kevin C Corbit
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | | | - Lia R Edmunds
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Jennifer L Tran
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | - Nicholas B Vera
- Cardiovascular and Metabolic Diseases, Pfizer, Cambridge, MA
| | - Derek M Erion
- Cardiovascular and Metabolic Diseases, Pfizer, Cambridge, MA
| | - Rahul C Deo
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | - Rachel J Perry
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Gerald I Shulman
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT
- Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT
| | - Michael J Jurczak
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA
| | - Ethan J Weiss
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
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Samuel VT, Shulman GI. Nonalcoholic Fatty Liver Disease as a Nexus of Metabolic and Hepatic Diseases. Cell Metab 2018; 27:22-41. [PMID: 28867301 PMCID: PMC5762395 DOI: 10.1016/j.cmet.2017.08.002] [Citation(s) in RCA: 452] [Impact Index Per Article: 75.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/01/2017] [Accepted: 08/01/2017] [Indexed: 12/15/2022]
Abstract
NAFLD is closely linked with hepatic insulin resistance. Accumulation of hepatic diacylglycerol activates PKC-ε, impairing insulin receptor activation and insulin-stimulated glycogen synthesis. Peripheral insulin resistance indirectly influences hepatic glucose and lipid metabolism by increasing flux of substrates that promote lipogenesis (glucose and fatty acids) and gluconeogenesis (glycerol and fatty acid-derived acetyl-CoA, an allosteric activator of pyruvate carboxylase). Weight loss with diet or bariatric surgery effectively treats NAFLD, but drugs specifically approved for NAFLD are not available. Some new pharmacological strategies act broadly to alter energy balance or influence pathways that contribute to NAFLD (e.g., agonists for PPAR γ, PPAR α/δ, FXR and analogs for FGF-21, and GLP-1). Others specifically inhibit key enzymes involved in lipid synthesis (e.g., mitochondrial pyruvate carrier, acetyl-CoA carboxylase, stearoyl-CoA desaturase, and monoacyl- and diacyl-glycerol transferases). Finally, a novel class of liver-targeted mitochondrial uncoupling agents increases hepatocellular energy expenditure, reversing the metabolic and hepatic complications of NAFLD.
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Affiliation(s)
- Varman T Samuel
- Department of Medicine, Yale University School of Medicine, New Haven, CT 06510, USA; Veterans Affairs Medical Center, West Haven, CT 06516, USA.
| | - Gerald I Shulman
- Department of Medicine, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06510, USA.
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Petersen MC, Shulman GI. Roles of Diacylglycerols and Ceramides in Hepatic Insulin Resistance. Trends Pharmacol Sci 2017; 38:649-665. [PMID: 28551355 DOI: 10.1016/j.tips.2017.04.004] [Citation(s) in RCA: 234] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/19/2017] [Accepted: 04/20/2017] [Indexed: 12/22/2022]
Abstract
Although ample evidence links hepatic lipid accumulation with hepatic insulin resistance, the mechanistic basis of this association is incompletely understood and controversial. Diacylglycerols (DAGs) and ceramides have emerged as the two best-studied putative mediators of lipid-induced hepatic insulin resistance. Both lipids were first associated with insulin resistance in skeletal muscle and were subsequently hypothesized to mediate insulin resistance in the liver. However, the putative roles for DAGs and ceramides in hepatic insulin resistance have proved more complex than originally imagined, with various genetic and pharmacologic manipulations yielding a vast and occasionally contradictory trove of data to sort. In this review we examine the state of this field, turning a critical eye toward both DAGs and ceramides as putative mediators of lipid-induced hepatic insulin resistance.
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Affiliation(s)
- Max C Petersen
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Gerald I Shulman
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06520, USA.
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