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Keenan SN, Meex RC, Lo JC, Montgomery MK, Watt MJ. Perilipin 5 deletion in hepatocytes remodels lipid metabolism and causes hepatic insulin resistance in mice. Obes Res Clin Pract 2019. [DOI: 10.1016/j.orcp.2018.11.101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Keenan SN, Meex RC, Lo JCY, Ryan A, Nie S, Montgomery MK, Watt MJ. Perilipin 5 Deletion in Hepatocytes Remodels Lipid Metabolism and Causes Hepatic Insulin Resistance in Mice. Diabetes 2019; 68:543-555. [PMID: 30617219 DOI: 10.2337/db18-0670] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 12/13/2018] [Indexed: 11/13/2022]
Abstract
Defects in hepatic lipid metabolism cause nonalcoholic fatty liver disease and insulin resistance, and these pathologies are closely linked. Regulation of lipid droplet metabolism is central to the control of intracellular fatty acid fluxes, and perilipin 5 (PLIN5) is important in this process. We examined the role of PLIN5 on hepatic lipid metabolism and systemic glycemic control using liver-specific Plin5-deficient mice (Plin5LKO ). Hepatocytes isolated from Plin5LKO mice exhibited marked changes in lipid metabolism characterized by decreased fatty acid uptake and storage, decreased fatty acid oxidation that was associated with reduced contact between lipid droplets and mitochondria, and reduced triglyceride secretion. With consumption of a high-fat diet, Plin5LKO mice accumulated intrahepatic triglyceride, without significant changes in inflammation, ceramide or diglyceride contents, endoplasmic reticulum stress, or autophagy. Instead, livers of Plin5LKO mice exhibited activation of c-Jun N-terminal kinase, impaired insulin signal transduction, and insulin resistance, which impaired systemic insulin action and glycemic control. Re-expression of Plin5 in the livers of Plin5LKO mice reversed these effects. Together, we show that Plin5 is an important modulator of intrahepatic lipid metabolism and suggest that the increased Plin5 expression that occurs with overnutrition may play an important role in preventing hepatic insulin resistance.
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Affiliation(s)
- Stacey N Keenan
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Ruth C Meex
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
- Department of Human Biology, School of Nutrition and Translational Research in Metabolism (NUTRIM), Faculty of Health, Medicine and Life Sciences, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Jennifer C Y Lo
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Andrew Ryan
- TissuPath, Mount Waverley, Victoria, Australia
| | - Shuai Nie
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science & Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Magdalene K Montgomery
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Matthew J Watt
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
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Ow CPC, Ngo JP, Ullah MM, Barsha G, Meex RC, Watt MJ, Hilliard LM, Koeners MP, Evans RG. Absence of renal hypoxia in the subacute phase of severe renal ischemia-reperfusion injury. Am J Physiol Renal Physiol 2018; 315:F1358-F1369. [PMID: 30110566 PMCID: PMC6293301 DOI: 10.1152/ajprenal.00249.2018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Tissue hypoxia has been proposed as an important event in renal ischemia-reperfusion injury (IRI), particularly during the period of ischemia and in the immediate hours following reperfusion. However, little is known about renal oxygenation during the subacute phase of IRI. We employed four different methods to assess the temporal and spatial changes in tissue oxygenation during the subacute phase (24 h and 5 days after reperfusion) of a severe form of renal IRI in rats. We hypothesized that the kidney is hypoxic 24 h and 5 days after an hour of bilateral renal ischemia, driven by a disturbed balance between renal oxygen delivery (Do2) and oxygen consumption (V̇o2). Renal Do2 was not significantly reduced in the subacute phase of IRI. In contrast, renal V̇o2 was 55% less 24 h after reperfusion and 49% less 5 days after reperfusion than after sham ischemia. Inner medullary tissue Po2, measured by radiotelemetry, was 25 ± 12% (mean ± SE) greater 24 h after ischemia than after sham ischemia. By 5 days after reperfusion, tissue Po2 was similar to that in rats subjected to sham ischemia. Tissue Po2 measured by Clark electrode was consistently greater 24 h, but not 5 days, after ischemia than after sham ischemia. Cellular hypoxia, assessed by pimonidazole adduct immunohistochemistry, was largely absent at both time points, and tissue levels of hypoxia-inducible factors were downregulated following renal ischemia. Thus, in this model of severe IRI, tissue hypoxia does not appear to be an obligatory event during the subacute phase, likely because of the markedly reduced oxygen consumption.
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Affiliation(s)
- Connie P C Ow
- Cardiovascular Disease Program, Biomedicine Discovery Institute, Department of Physiology, Monash University , Melbourne, Victoria , Australia
| | - Jennifer P Ngo
- Cardiovascular Disease Program, Biomedicine Discovery Institute, Department of Physiology, Monash University , Melbourne, Victoria , Australia
| | - Md Mahbub Ullah
- Cardiovascular Disease Program, Biomedicine Discovery Institute, Department of Physiology, Monash University , Melbourne, Victoria , Australia
| | - Giannie Barsha
- Cardiovascular Disease Program, Biomedicine Discovery Institute, Department of Physiology, Monash University , Melbourne, Victoria , Australia
| | - Ruth C Meex
- Department of Human Biology, NUTRIM School of Nutritional and Translational Research in Metabolism, Maastricht University Medical Centre , Maastricht , The Netherlands
| | - Matthew J Watt
- Metabolism, Diabetes and Obesity Program, Biomedicine Discovery Institute, Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Lucinda M Hilliard
- Cardiovascular Disease Program, Biomedicine Discovery Institute, Department of Physiology, Monash University , Melbourne, Victoria , Australia
| | - Maarten P Koeners
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University of Bristol , Bristol , United Kingdom.,Institute of Biomedical and Clinical Science, University of Exeter Medical School , Exeter , United Kingdom
| | - Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute, Department of Physiology, Monash University , Melbourne, Victoria , Australia
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Meex RC, Hoy AJ, Morris A, Brown RD, Lo JCY, Burke M, Goode RJA, Kingwell BA, Kraakman MJ, Febbraio MA, Greve JW, Rensen SS, Molloy MP, Lancaster GI, Bruce CR, Watt MJ. Fetuin B Is a Secreted Hepatocyte Factor Linking Steatosis to Impaired Glucose Metabolism. Cell Metab 2015; 22:1078-89. [PMID: 26603189 DOI: 10.1016/j.cmet.2015.09.023] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 08/04/2015] [Accepted: 09/23/2015] [Indexed: 12/18/2022]
Abstract
Liver steatosis is associated with the development of insulin resistance and the pathogenesis of type 2 diabetes. We tested the hypothesis that protein signals originating from steatotic hepatocytes communicate with other cells to modulate metabolic phenotypes. We show that the secreted factors from steatotic hepatocytes induce pro-inflammatory signaling and insulin resistance in cultured cells. Next, we identified 168 hepatokines, of which 32 were differentially secreted in steatotic versus non-steatotic hepatocytes. Targeted analysis showed that fetuin B was increased in humans with liver steatosis and patients with type 2 diabetes. Fetuin B impaired insulin action in myotubes and hepatocytes and caused glucose intolerance in mice. Silencing of fetuin B in obese mice improved glucose tolerance. We conclude that the protein secretory profile of hepatocytes is altered with steatosis and is linked to inflammation and insulin resistance. Therefore, preventing steatosis may limit the development of dysregulated glucose metabolism in settings of overnutrition.
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Affiliation(s)
- Ruth C Meex
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia
| | - Andrew J Hoy
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia
| | - Alexander Morris
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia
| | - Russell D Brown
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia
| | - Jennifer C Y Lo
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia
| | - Melissa Burke
- Biotechnology Research Laboratories, Department of Physiology, Monash University, Clayton, VIC 3800, Australia; Mill Hill Laboratory, The Francis Crick Institute, London NW7 1AA, UK
| | - Robert J A Goode
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | | | | | - Mark A Febbraio
- Baker IDI Heart and Diabetes Institute, Melbourne, VIC 3004, Australia; The Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
| | - Jan Willem Greve
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Department of General Surgery, Maastricht, the Netherlands
| | - Sander S Rensen
- NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Department of General Surgery, Maastricht, the Netherlands
| | - Mark P Molloy
- Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW 2109, Australia
| | | | - Clinton R Bruce
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia
| | - Matthew J Watt
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program, and Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, VIC 3800, Australia.
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Koves TR, Sparks LM, Kovalik JP, Mosedale M, Arumugam R, DeBalsi KL, Everingham K, Thorne L, Phielix E, Meex RC, Kien CL, Hesselink MKC, Schrauwen P, Muoio DM. PPARγ coactivator-1α contributes to exercise-induced regulation of intramuscular lipid droplet programming in mice and humans. J Lipid Res 2013; 54:522-34. [PMID: 23175776 PMCID: PMC3588877 DOI: 10.1194/jlr.p028910] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [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: 05/29/2012] [Revised: 10/27/2012] [Indexed: 11/20/2022] Open
Abstract
Intramuscular accumulation of triacylglycerol, in the form of lipid droplets (LD), has gained widespread attention as a hallmark of metabolic disease and insulin resistance. Paradoxically, LDs also amass in muscles of highly trained endurance athletes who are exquisitely insulin sensitive. Understanding the molecular mechanisms that mediate the expansion and appropriate metabolic control of LDs in the context of habitual physical activity could lead to new therapeutic opportunities. Herein, we show that acute exercise elicits robust upregulation of a broad program of genes involved in regulating LD assembly, morphology, localization, and mobilization. Prominent among these was perilipin-5, a scaffolding protein that affects the spatial and metabolic interactions between LD and their surrounding mitochondrial reticulum. Studies in transgenic mice and primary human skeletal myocytes established a key role for the exercise-responsive transcriptional coactivator PGC-1α in coordinating intramuscular LD programming with mitochondrial remodeling. Moreover, translational studies comparing physically active versus inactive humans identified a remarkably strong association between expression of intramuscular LD genes and enhanced insulin action in exercise-trained subjects. These results reveal an intimate molecular connection between intramuscular LD biology and mitochondrial metabolism that could prove relevant to the etiology and treatment of insulin resistance and other disorders of lipid imbalance.
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Affiliation(s)
- Timothy R. Koves
- Sarah W. Stedman Nutrition & Metabolism Center, Duke University, Durham, NC
- Department of Medicine, Duke University, Durham, NC
| | - Lauren M. Sparks
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, FL
| | - J. P. Kovalik
- Sarah W. Stedman Nutrition & Metabolism Center, Duke University, Durham, NC
| | - Merrie Mosedale
- Sarah W. Stedman Nutrition & Metabolism Center, Duke University, Durham, NC
| | - Ramamani Arumugam
- Sarah W. Stedman Nutrition & Metabolism Center, Duke University, Durham, NC
| | - Karen L. DeBalsi
- Sarah W. Stedman Nutrition & Metabolism Center, Duke University, Durham, NC
| | - Karen Everingham
- Department of Pediatrics and Medicine, University of Vermont, Colchester, VT
| | - Leigh Thorne
- Department of Pathology & Laboratory Medicine, University of North Carolina, Chapel-Hill, NC
| | - Esther Phielix
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands
| | - Ruth C. Meex
- Department of Human Movement Sciences, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands
| | - C. Lawrence Kien
- Department of Pediatrics and Medicine, University of Vermont, Colchester, VT
| | - Matthijs K. C. Hesselink
- Department of Human Movement Sciences, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands
| | - Patrick Schrauwen
- Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands
| | - Deborah M. Muoio
- Sarah W. Stedman Nutrition & Metabolism Center, Duke University, Durham, NC
- Department of Medicine, Duke University, Durham, NC
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC
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Boon J, Hoy AJ, Stark R, Brown RD, Meex RC, Henstridge DC, Schenk S, Meikle PJ, Horowitz JF, Kingwell BA, Bruce CR, Watt MJ. Ceramides contained in LDL are elevated in type 2 diabetes and promote inflammation and skeletal muscle insulin resistance. Diabetes 2013; 62:401-10. [PMID: 23139352 PMCID: PMC3554351 DOI: 10.2337/db12-0686] [Citation(s) in RCA: 223] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Dysregulated lipid metabolism and inflammation are linked to the development of insulin resistance in obesity, and the intracellular accumulation of the sphingolipid ceramide has been implicated in these processes. Here, we explored the role of circulating ceramide on the pathogenesis of insulin resistance. Ceramide transported in LDL is elevated in the plasma of obese patients with type 2 diabetes and correlated with insulin resistance but not with the degree of obesity. Treating cultured myotubes with LDL containing ceramide promoted ceramide accrual in cells and was accompanied by reduced insulin-stimulated glucose uptake, Akt phosphorylation, and GLUT4 translocation compared with LDL deficient in ceramide. LDL-ceramide induced a proinflammatory response in cultured macrophages via toll-like receptor-dependent and -independent mechanisms. Finally, infusing LDL-ceramide into lean mice reduced insulin-stimulated glucose uptake, and this was due to impaired insulin action specifically in skeletal muscle. These newly identified roles of LDL-ceramide suggest that strategies aimed at reducing hepatic ceramide production or reducing ceramide packaging into lipoproteins may improve skeletal muscle insulin action.
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MESH Headings
- Animals
- Cells, Cultured
- Ceramides/blood
- Ceramides/pharmacology
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/metabolism
- Female
- Glucose/metabolism
- Glucose Transporter Type 4/metabolism
- Humans
- Inflammation/blood
- Inflammation/metabolism
- Insulin/metabolism
- Insulin Resistance/physiology
- Lipoproteins, LDL/blood
- Lipoproteins, LDL/pharmacology
- Macrophages/drug effects
- Macrophages/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Obesity/blood
- Obesity/metabolism
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- Toll-Like Receptors/metabolism
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Affiliation(s)
- James Boon
- Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Andrew J. Hoy
- Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Romana Stark
- Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Russell D. Brown
- Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Ruth C. Meex
- Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, Victoria, Australia
| | | | - Simon Schenk
- Department of Orthopaedic Surgery, University of California, San Diego, California
| | - Peter J. Meikle
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | | | | | - Clinton R. Bruce
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Matthew J. Watt
- Biology of Lipid Metabolism Laboratory, Department of Physiology, Monash University, Clayton, Victoria, Australia
- Corresponding author: Matthew J. Watt,
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