1
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Zhang C, Steadman M, Santos HP, Shaikh SR, Xavier RM. GPAT1 Activity and Abundant Palmitic Acid Impair Insulin Suppression of Hepatic Glucose Production in Primary Mouse Hepatocytes. J Nutr 2024; 154:1109-1118. [PMID: 38354952 PMCID: PMC11007742 DOI: 10.1016/j.tjnut.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 01/31/2024] [Accepted: 02/07/2024] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Glycerol-3-phosphate acyltransferase (GPAT) activity is correlated with obesity and insulin resistance in mice and humans. However, insulin resistance exists in people with normal body weight, and individuals with obesity may be metabolically healthy, implying the presence of complex pathophysiologic mechanisms underpinning insulin resistance. OBJECTIVE We asked what conditions related to GPAT1 must be met concurrently for hepatic insulin resistance to occur. METHODS Mouse hepatocytes were overexpressed with GPATs via adenoviral infection or exposed to high or low concentrations of glucose. Glucose production by the cells and phosphatidic acid (PA) content in the cells were assayed, GPAT activity was measured, relative messenger RNA expressions of sterol-regulatory element-binding protein 1c (SREBP1c), carbohydrate response element-binding protein (ChREBP), and GPAT1 were analyzed, and insulin signaling transduction was examined. RESULTS Overexpressing GPAT1 in mouse hepatocytes impaired insulin's suppression of glucose production, together with an increase in both N-ethylmaleimide-resistant GPAT activity and the content of di-16:0 PA. Akt-mediated insulin signaling was inhibited in hepatocytes that overexpressed GPAT1. When the cells were exposed to high-glucose concentrations, insulin suppression of glucose production was impaired, and adding palmitic acid exacerbated this impairment. High-glucose exposure increased the expression of SREBP1c, ChREBP, and GPAT1 by ∼2-, 5-, and 5.7-fold, respectively. The addition of 200 mM palmitic acid or linoleic acid to the culture media did not change the upregulation of expression of these genes by high glucose. High-glucose exposure increased di-16:0 PA content in the cells, and adding palmitic acid further increased di-16:0 PA content. The effect was specific to palmitic acid because linoleic acid did not show these effects. CONCLUSION These data demonstrate that high-GPAT1 activity, whether induced by glucose exposure or acquired by transfection, and abundant palmitic acid can impair insulin's ability to suppress hepatic glucose production in primary mouse hepatocytes.
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Affiliation(s)
- Chongben Zhang
- Biobehavioral Laboratory, School of Nursing, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
| | - Mathew Steadman
- Biobehavioral Laboratory, School of Nursing, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Hudson P Santos
- School of Nursing and Health Studies, University of Miami, Coral Gables, FL, United States
| | - Saame R Shaikh
- Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Rose Mary Xavier
- Biobehavioral Laboratory, School of Nursing, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States.
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2
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Zhong R, Zhu Y, Zhang H, Huo Y, Huang Y, Cheng W, Liang P. Integrated lipidomic and transcriptomic analyses reveal the mechanism of large yellow croaker roe phospholipids on lipid metabolism in normal-diet mice. Food Funct 2022; 13:12852-12869. [PMID: 36444685 DOI: 10.1039/d2fo02736d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Large yellow croaker roe phospholipids (LYCRPLs) could regulate the accumulation of triglycerides and blood lipid levels. However, there exists little research on the mechanism of LYCRPLs on lipid metabolism in normal-diet mice. In this work, the mice on a normal diet were given low-dose, medium-dose, and high-dose LYCRPLs by intragastric administration for 6 weeks. At the same time, the physiological and biochemical indicators of the mice were determined, and the histomorphological observation of the liver and epididymal fat was carried out. In addition, we examined the gene expression and lipid metabolites in the liver of mice using transcriptomic and lipidomic and performed a correlation analysis. The results showed that LYCRPLs regulated the lipid metabolism of normal-diet mice by affecting the expression of the glycerolipid metabolism pathway, insulin resistance pathway, and cholesterol metabolism pathway. This study not only elucidated the main pathway by which LYCRPLs regulate lipid metabolism, but also laid a foundation for exploring LYCRPLs as functional food supplements.
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Affiliation(s)
- Rongbin Zhong
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
| | - Yujie Zhu
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
| | - Huadan Zhang
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
| | - Yuming Huo
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
| | - Ying Huang
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
| | - Wenjian Cheng
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
| | - Peng Liang
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, 350002 Fujian, China. .,Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fuzhou, 350002, Fujian, China
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3
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Prenatal Low-Protein Diet Affects Mitochondrial Structure and Function in the Skeletal Muscle of Adult Female Offspring. Nutrients 2022; 14:nu14061158. [PMID: 35334815 PMCID: PMC8954615 DOI: 10.3390/nu14061158] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/03/2022] [Accepted: 03/08/2022] [Indexed: 02/06/2023] Open
Abstract
Gestational low-protein (LP) diet leads to glucose intolerance and insulin resistance in adult offspring. We had earlier demonstrated that LP programming affects glucose disposal in females. Mitochondrial health is crucial for normal glucose metabolism in skeletal muscle. In this study, we sought to analyze mitochondrial structure, function, and associated genes in skeletal muscles to explore the molecular mechanism of insulin resistance LP-programmed female offspring. On day four of pregnancy, rats were assigned to a control diet containing 20% protein or an isocaloric 6% protein-containing diet. Standard laboratory diet was given to the dams after delivery until the end of weaning and to pups after weaning. Gestational LP diet led to changes in mitochondrial ultrastructure in the gastrocnemius muscles, including a nine-fold increase in the presence of giant mitochondria along with unevenly formed cristae. Further, functional analysis showed that LP programming caused impaired mitochondrial functions. Although the mitochondrial copy number did not show significant changes, key genes involved in mitochondrial structure and function such as Fis1, Opa1, Mfn2, Nrf1, Nrf2, Pgc1b, Cox4b, Esrra, and Vdac were dysregulated. Our study shows that prenatal LP programming induced disruption in mitochondrial ultrastructure and function in the skeletal muscle of female offspring.
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4
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Takagi H, Ikehara T, Hashimoto K, Tanimoto K, Shimazaki A, Kashiwagi Y, Sakamoto S, Yukioka H. Acetyl-CoA carboxylase 2 inhibition reduces skeletal muscle bioactive lipid content and attenuates progression of type 2 diabetes in Zucker diabetic fatty rats. Eur J Pharmacol 2021; 910:174451. [PMID: 34454928 DOI: 10.1016/j.ejphar.2021.174451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 11/17/2022]
Abstract
Intramyocellular lipid (IMCL) accumulation in skeletal muscle is closely associated with development of insulin resistance. In particular, diacylglycerol and ceramide are currently considered as causal bioactive lipids for impaired insulin action. Recently, inhibition of acetyl-CoA carboxylase 2 (ACC2), which negatively modulates mitochondrial fatty acid oxidation, has been shown to reduce total IMCL content and improve whole-body insulin resistance. This study aimed to investigate whether ACC2 inhibition-induced compositional changes in bioactive lipids, especially diacylglycerol and ceramide, within skeletal muscle contribute to the improved insulin resistance. In skeletal muscle of normal rats, treatment of the ACC2 inhibitor compound 2e significantly decreased both diacylglycerol and ceramide levels while having no significant impact on other lipid metabolite levels. In skeletal muscle of Zucker diabetic fatty (ZDF) rats, which exhibited greater lipid accumulation than that of normal rats, compound 2e significantly decreased diacylglycerol and ceramide levels corresponding to reduced long chain acyl-CoA pools. Additionally, in the lipid metabolomics study, ZDF rats treated with compound 2e also showed improved diabetes-related metabolic disturbance, as reflected by delayed hyperinsulinemia as well as upregulated gene expression associated with diabetic conditions in skeletal muscle. These metabolic improvements were strongly correlated with the bioactive lipid reductions. Furthermore, long-term treatment of compound 2e markedly improved whole-body insulin resistance, attenuated hyperglycemia and delayed insulin secretion defect even at severe diabetic conditions. These findings suggest that ACC2 inhibition decreases diacylglycerol and ceramide accumulation within skeletal muscle by enhancing acyl-CoA breakdown, leading to attenuation of lipid-induced insulin resistance and subsequent diabetes progression.
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Affiliation(s)
- Hiroyuki Takagi
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan.
| | - Tatsuya Ikehara
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
| | - Kumi Hashimoto
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
| | - Keiichi Tanimoto
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
| | - Atsuyuki Shimazaki
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
| | - Yuto Kashiwagi
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
| | - Shingo Sakamoto
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
| | - Hideo Yukioka
- Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka, Osaka, 561-0825, Japan
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5
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Alemany M. Estrogens and the regulation of glucose metabolism. World J Diabetes 2021; 12:1622-1654. [PMID: 34754368 PMCID: PMC8554369 DOI: 10.4239/wjd.v12.i10.1622] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/10/2021] [Accepted: 04/14/2021] [Indexed: 02/06/2023] Open
Abstract
The main estrogens: estradiol, estrone, and their acyl-esters have been studied essentially related to their classical estrogenic and pharmacologic functions. However, their main effect in the body is probably the sustained control of core energy metabolism. Estrogen nuclear and membrane receptors show an extraordinary flexibility in the modulation of metabolic responses, and largely explain gender and age differences in energy metabolism: part of these mechanisms is already sufficiently known to justify both. With regard to energy, the estrogen molecular species act essentially through four key functions: (1) Facilitation of insulin secretion and control of glucose availability; (2) Modulation of energy partition, favoring the use of lipid as the main energy substrate when more available than carbohydrates; (3) Functional protection through antioxidant mechanisms; and (4) Central effects (largely through neural modulation) on whole body energy management. Analyzing the different actions of estrone, estradiol and their acyl esters, a tentative classification based on structure/effects has been postulated. Either separately or as a group, estrogens provide a comprehensive explanation that not all their quite diverse actions are related solely to specific molecules. As a group, they constitute a powerful synergic action complex. In consequence, estrogens may be considered wardens of energy homeostasis.
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Affiliation(s)
- Marià Alemany
- Faculty of Biology, University of Barcelona, Barcelona 08028, Catalonia, Spain
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6
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Maude H, Lau W, Maniatis N, Andrew T. New Insights Into Mitochondrial Dysfunction at Disease Susceptibility Loci in the Development of Type 2 Diabetes. Front Endocrinol (Lausanne) 2021; 12:694893. [PMID: 34456865 PMCID: PMC8385132 DOI: 10.3389/fendo.2021.694893] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 07/08/2021] [Indexed: 12/25/2022] Open
Abstract
This study investigated the potential genetic mechanisms which underlie adipose tissue mitochondrial dysfunction in Type 2 diabetes (T2D), by systematically identifying nuclear-encoded mitochondrial genes (NEMGs) among the genes regulated by T2D-associated genetic loci. The target genes of these 'disease loci' were identified by mapping genetic loci associated with both disease and gene expression levels (expression quantitative trait loci, eQTL) using high resolution genetic maps, with independent estimates co-locating to within a small genetic distance. These co-locating signals were defined as T2D-eQTL and the target genes as T2D cis-genes. In total, 763 cis-genes were associated with T2D-eQTL, of which 50 were NEMGs. Independent gene expression datasets for T2D and insulin resistant cases and controls confirmed that the cis-genes and cis-NEMGs were enriched for differential expression in cases, providing independent validation that genetic maps can identify informative functional genes. Two additional results were consistent with a potential role of T2D-eQTL in regulating the 50 identified cis-NEMGs in the context of T2D risk: (1) the 50 cis-NEMGs showed greater differential expression compared to other NEMGs and (2) other NEMGs showed a trend towards significantly decreased expression if their expression levels correlated more highly with the subset of 50 cis-NEMGs. These 50 cis-NEMGs, which are differentially expressed and associated with mapped T2D disease loci, encode proteins acting within key mitochondrial pathways, including some of current therapeutic interest such as the metabolism of branched-chain amino acids, GABA and biotin.
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Affiliation(s)
- Hannah Maude
- Department of Metabolism, Digestion & Reproduction, Imperial College, London, United Kingdom
| | - Winston Lau
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Nikolas Maniatis
- Department of Genetics, Evolution and Environment, University College London, London, United Kingdom
| | - Toby Andrew
- Department of Metabolism, Digestion & Reproduction, Imperial College, London, United Kingdom
- *Correspondence: Toby Andrew,
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7
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Xu J, Pei Y, Lu J, Liang X, Li Y, Wang J, Zhang Y. LncRNA SNHG7 alleviates IL-1β-induced osteoarthritis by inhibiting miR-214-5p-mediated PPARGC1B signaling pathways. Int Immunopharmacol 2021; 90:107150. [PMID: 33296783 DOI: 10.1016/j.intimp.2020.107150] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND As a common joint disease, osteoarthritis (OA) is the main cause of limited joint mobility and disability. The role of lncRNAs in the regulation of OA is increasingly discovered. Therefore, further exploring the function of SNHG7 in OA is of great significance for understanding its occurrence and development. METHODS We used interleukin-1β (IL-1β) to treat to establish an OA model primary on chondrocytes in vitro, and gain- and loss of function assays of SNHG7 and miR-214-5p were conducted. The cell viability and apoptosis of chondrocytes were detected by CCK8 assay, BrdU assay and flow cytometry. The inflammatory cytokines (IL-1β, IL-6 and TNF-α), NLRP3 inflammasome, protein level of PPARGC1B, PPARγ, P38 and NF-κB were determined by RT-PCR and/or western blot. RESULTS The results showed that SNHG7 was distinctly downregulated, while miR-214-5p was significantly upregulated in OA patients and primary chondrocytes treated with IL-1β. In addition, SNHG7 enhanced cell viability, inhibited apoptosis and inflammation of IL-1β-mediated chondrocytes. In contrast, miR-214-5p upregulation reduced viability, promoted apoptosis and inflammation of chondrocytes. Mechanistically, SNHG7 served as a competitive endogenous RNA by sponging miR-214-5p, which targeted PPARGC1B. Besides, the results of the compensation experiment affirmed that miR-214-5p attenuates SNHG7-mediated protective effects on IL-1β-mediated chondrocytes against apoptosis and inflammation, and activating PPARγ pathway markedly dampened the cytotoxic effects of miR-214-5p. CONCLUSIONS Collectively, The above results confirmed that SNHG7 prevents IL-1β induced OA by inhibiting NLRP3 inflammasome and apoptosis through miR-214-5p/PPARGC1B axis.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Cartilage, Articular/drug effects
- Cartilage, Articular/metabolism
- Cartilage, Articular/pathology
- Case-Control Studies
- Cells, Cultured
- Chondrocytes/drug effects
- Chondrocytes/metabolism
- Chondrocytes/pathology
- Humans
- Inflammasomes/metabolism
- Inflammation Mediators/metabolism
- Interleukin-1beta/toxicity
- Knee Joint/drug effects
- Knee Joint/metabolism
- Knee Joint/pathology
- Mice, Inbred C57BL
- MicroRNAs/genetics
- MicroRNAs/metabolism
- NLR Family, Pyrin Domain-Containing 3 Protein/metabolism
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Osteoarthritis, Knee/genetics
- Osteoarthritis, Knee/metabolism
- Osteoarthritis, Knee/pathology
- RNA, Long Noncoding/genetics
- RNA, Long Noncoding/metabolism
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Signal Transduction
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Mice
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Affiliation(s)
- Junkui Xu
- Foot Ankle Center, The Xi'an Honghui Hospital, Xi'an 710054, Shaanxi, China
| | - Yanjiang Pei
- Department of Urology Surgery, The Xi'an Honghui Hospital, Xi'an 710054, Shaanxi, China
| | - Jun Lu
- Foot Ankle Center, The Xi'an Honghui Hospital, Xi'an 710054, Shaanxi, China
| | - Xiaojun Liang
- Foot Ankle Center, The Xi'an Honghui Hospital, Xi'an 710054, Shaanxi, China
| | - Yi Li
- Foot Ankle Center, The Xi'an Honghui Hospital, Xi'an 710054, Shaanxi, China
| | - Junhu Wang
- Foot Ankle Center, The Xi'an Honghui Hospital, Xi'an 710054, Shaanxi, China
| | - Yingang Zhang
- Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, Shaanxi, China.
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8
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Genders AJ, Holloway GP, Bishop DJ. Are Alterations in Skeletal Muscle Mitochondria a Cause or Consequence of Insulin Resistance? Int J Mol Sci 2020; 21:ijms21186948. [PMID: 32971810 PMCID: PMC7554894 DOI: 10.3390/ijms21186948] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 09/18/2020] [Accepted: 09/18/2020] [Indexed: 12/14/2022] Open
Abstract
As a major site of glucose uptake following a meal, skeletal muscle has an important role in whole-body glucose metabolism. Evidence in humans and animal models of insulin resistance and type 2 diabetes suggests that alterations in mitochondrial characteristics accompany the development of skeletal muscle insulin resistance. However, it is unclear whether changes in mitochondrial content, respiratory function, or substrate oxidation are central to the development of insulin resistance or occur in response to insulin resistance. Thus, this review will aim to evaluate the apparent conflicting information placing mitochondria as a key organelle in the development of insulin resistance in skeletal muscle.
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Affiliation(s)
- Amanda J. Genders
- Institute for Health and Sport (iHeS), Victoria University, Melbourne 8001, Australia;
- Correspondence: ; Tel.: +61-3-9919-9556
| | - Graham P. Holloway
- Dept. Human Health and Nutritional Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada;
| | - David J. Bishop
- Institute for Health and Sport (iHeS), Victoria University, Melbourne 8001, Australia;
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9
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Dirks ML, Miotto PM, Goossens GH, Senden JM, Petrick HL, Kranenburg J, Loon LJ, Holloway GP. Short‐term bed rest‐induced insulin resistance cannot be explained by increased mitochondrial H2O2emission. J Physiol 2019; 598:123-137. [DOI: 10.1113/jp278920] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/11/2019] [Indexed: 12/16/2022] Open
Affiliation(s)
- Marlou L. Dirks
- NUTRIM School of Nutrition and Translational Research in MetabolismMaastricht University Medical Centre+ the Netherlands
| | - Paula M. Miotto
- Human Health & Nutritional SciencesUniversity of Guelph Guelph Ontario Canada
| | - Gijs H. Goossens
- NUTRIM School of Nutrition and Translational Research in MetabolismMaastricht University Medical Centre+ the Netherlands
| | - Joan M. Senden
- NUTRIM School of Nutrition and Translational Research in MetabolismMaastricht University Medical Centre+ the Netherlands
| | - Heather L. Petrick
- Human Health & Nutritional SciencesUniversity of Guelph Guelph Ontario Canada
| | - Janneau Kranenburg
- NUTRIM School of Nutrition and Translational Research in MetabolismMaastricht University Medical Centre+ the Netherlands
| | - Luc J.C. Loon
- NUTRIM School of Nutrition and Translational Research in MetabolismMaastricht University Medical Centre+ the Netherlands
| | - Graham P. Holloway
- Human Health & Nutritional SciencesUniversity of Guelph Guelph Ontario Canada
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10
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Sergi D, Naumovski N, Heilbronn LK, Abeywardena M, O'Callaghan N, Lionetti L, Luscombe-Marsh N. Mitochondrial (Dys)function and Insulin Resistance: From Pathophysiological Molecular Mechanisms to the Impact of Diet. Front Physiol 2019; 10:532. [PMID: 31130874 PMCID: PMC6510277 DOI: 10.3389/fphys.2019.00532] [Citation(s) in RCA: 185] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 04/15/2019] [Indexed: 12/17/2022] Open
Abstract
Mitochondrial dysfunction has been implicated in the pathogenesis of insulin resistance, the hallmark of type 2 diabetes mellitus (T2DM). However, the cause-effect relationship remains to be fully elucidated. Compelling evidence suggests that boosting mitochondrial function may represent a valuable therapeutic tool to improve insulin sensitivity. Mitochondria are highly dynamic organelles, which adapt to short- and long-term metabolic perturbations by undergoing fusion and fission cycles, spatial rearrangement of the electron transport chain complexes into supercomplexes and biogenesis governed by peroxisome proliferator-activated receptor γ co-activator 1α (PGC 1α). However, these processes appear to be dysregulated in type 2 diabetic individuals. Herein, we describe the mechanistic link between mitochondrial dysfunction and insulin resistance in skeletal muscle alongside the intracellular pathways orchestrating mitochondrial bioenergetics. We then review current evidence on nutritional tools, including fatty acids, amino acids, caloric restriction and food bioactive derivatives, which may enhance insulin sensitivity by therapeutically targeting mitochondrial function and biogenesis.
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Affiliation(s)
- Domenico Sergi
- Nutrition and Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, SA, Australia.,Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
| | - Nenad Naumovski
- Faculty of Health, University of Canberra, Canberra, ACT, Australia.,Collaborative Research in Bioactives and Biomarkers (CRIBB) Group, Canberra, ACT, Australia
| | | | - Mahinda Abeywardena
- Nutrition and Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, SA, Australia
| | - Nathan O'Callaghan
- Nutrition and Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, SA, Australia
| | - Lillà Lionetti
- Department of Chemistry and Biology "A. Zambelli", University of Salerno, Fisciano, Italy
| | - Natalie Luscombe-Marsh
- Nutrition and Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, SA, Australia.,Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia
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11
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Bakshi I, Brown SHJ, Brandon AE, Suryana E, Mitchell TW, Turner N, Cooney GJ. Increasing Acyl CoA thioesterase activity alters phospholipid profile without effect on insulin action in skeletal muscle of rats. Sci Rep 2018; 8:13967. [PMID: 30228369 PMCID: PMC6143561 DOI: 10.1038/s41598-018-32354-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 05/18/2018] [Indexed: 12/25/2022] Open
Abstract
Increased lipid metabolism in muscle is associated with insulin resistance and therefore, many strategies have been employed to alter fatty acid metabolism and study the impact on insulin action. Metabolism of fatty acid requires activation to fatty acyl CoA by Acyl CoA synthases (ACSL) and fatty acyl CoA can be hydrolysed by Acyl CoA thioesterases (Acot). Thioesterase activity is low in muscle, so we overexpressed Acot7 in muscle of chow and high-fat diet (HFD) rats and investigated effects on insulin action. Acot7 overexpression modified specific phosphatidylcholine and phosphatidylethanolamine species in tibialis muscle of chow rats to levels similar to those observed in control HFD muscle. The changes in phospholipid species did not alter glucose uptake in tibialis muscle under hyperinsulinaemic/euglycaemic clamped conditions. Acot7 overexpression in white extensor digitorum longus (EDL) muscle increased complete fatty acid oxidation ex-vivo but was not associated with any changes in glucose uptake in-vivo, however overexpression of Acot7 in red EDL reduced insulin-stimulated glucose uptake in-vivo which correlated with increased incomplete fatty acid oxidation ex-vivo. In summary, although overexpression of Acot7 in muscle altered some aspects of lipid profile and metabolism in muscle, this had no major effect on insulin-stimulated glucose uptake.
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Affiliation(s)
- Ishita Bakshi
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia
| | - Simon H J Brown
- School of Biological Sciences, University of Wollongong, Wollongong, Australia
| | - Amanda E Brandon
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia.,Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - Eurwin Suryana
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia
| | - Todd W Mitchell
- School of Biological Sciences, University of Wollongong, Wollongong, Australia
| | - Nigel Turner
- Department of Pharmacology, School of Medical Sciences, UNSW Sydney, Sydney, Australia
| | - Gregory J Cooney
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia. .,Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, Australia.
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12
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Small L, Brandon AE, Quek LE, Krycer JR, James DE, Turner N, Cooney GJ. Acute activation of pyruvate dehydrogenase increases glucose oxidation in muscle without changing glucose uptake. Am J Physiol Endocrinol Metab 2018; 315:E258-E266. [PMID: 29406780 DOI: 10.1152/ajpendo.00386.2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Pyruvate dehydrogenase (PDH) activity is a key component of the glucose/fatty acid cycle hypothesis for the regulation of glucose uptake and metabolism. We have investigated whether acute activation of PDH in muscle can alleviate the insulin resistance caused by feeding animals a high-fat diet (HFD). The importance of PDH activity in muscle glucose disposal under insulin-stimulated conditions was determined by infusing the PDH kinase inhibitor dichloroacetate (DCA) into HFD-fed Wistar rats during a hyperinsulinemic-euglycemic clamp. Acute DCA infusion did not alter glucose infusion rate, glucose disappearance, or hepatic glucose production but did decrease plasma lactate levels. DCA substantially increased muscle PDH activity; however, this did not improve insulin-stimulated glucose uptake in insulin-resistant muscle of HFD rats. DCA infusion increased the flux of pyruvate to acetyl-CoA and reduced glucose incorporation into glycogen and alanine in muscle. Similarly, in isolated muscle, DCA treatment increased glucose oxidation and decreased glycogen synthesis without changing glucose uptake. These results suggest that, although PDH activity controls the conversion of pyruvate to acetyl-CoA for oxidation, this has little effect on glucose uptake into muscle under insulin-stimulated conditions.
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Affiliation(s)
- Lewin Small
- Diabetes and Metabolism Division, Garvan Institute , Sydney, New South Wales , Australia
| | - Amanda E Brandon
- Diabetes and Metabolism Division, Garvan Institute , Sydney, New South Wales , Australia
- School of Medical Science, The University of Sydney, Charles Perkins Centre , New South Wales , Australia
| | - Lake-Ee Quek
- School of Mathematics and Statistics, The University of Sydney, Charles Perkins Centre , New South Wales , Australia
| | - James R Krycer
- School of Life and Environmental Science, The University of Sydney, Charles Perkins Centre , New South Wales , Australia
| | - David E James
- School of Life and Environmental Science, The University of Sydney, Charles Perkins Centre , New South Wales , Australia
| | - Nigel Turner
- Department of Pharmacology, School of Medical Science, University of New South Wales , Sydney, New South Wales , Australia
| | - Gregory J Cooney
- Diabetes and Metabolism Division, Garvan Institute , Sydney, New South Wales , Australia
- School of Medical Science, The University of Sydney, Charles Perkins Centre , New South Wales , Australia
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13
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Metcalfe LK, Smith GC, Turner N. Defining lipid mediators of insulin resistance - controversies and challenges. J Mol Endocrinol 2018; 62:JME-18-0023. [PMID: 30068522 DOI: 10.1530/jme-18-0023] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 07/04/2018] [Accepted: 07/31/2018] [Indexed: 12/31/2022]
Abstract
Essential elements of all cells, lipids play important roles in energy production, signalling and as structural components. Despite these critical functions, excessive availability and intracellular accumulation of lipid is now recognised as a major factor contributing to many human diseases, including obesity and diabetes. In the context of these metabolic disorders, ectopic deposition of lipid has been proposed to have deleterious effects of insulin action. While this relationship has been recognised for some time now, there is currently no unifying mechanism to explain how lipids precipitate the development of insulin resistance. This review summarises the evidence linking specific lipid molecules to the induction of insulin resistance, describing some of the current controversies and challenges for future studies in this field.
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Affiliation(s)
- Louise K Metcalfe
- L Metcalfe, Department of Pharmacology, School of Medical Sciences, UNSW Australia, Kensington, Australia
| | - Greg C Smith
- G Smith, Department of Pharmacology, School of Medical Sciences, UNSW Australia, Kensington, Australia
| | - Nigel Turner
- N Turner, Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, Australia
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14
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Jin T, Song Z, Weng J, Fantus IG. Curcumin and other dietary polyphenols: potential mechanisms of metabolic actions and therapy for diabetes and obesity. Am J Physiol Endocrinol Metab 2018; 314:E201-E205. [PMID: 29089337 DOI: 10.1152/ajpendo.00285.2017] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Recent controversy regarding the therapeutic potential of curcumin indicates the challenges to research in this field. Here, we highlight the investigations of curcumin and other plant-derived polyphenols that demonstrate their application to metabolic diseases, in particular, obesity and diabetes. Thus, a number of preclinical and clinical investigations have shown the beneficial effect of curcumin (and other dietary polyphenols) in attenuating body weight gain, improving insulin sensitivity, and preventing diabetes development in rodent models and prediabetic subjects. Other intervention studies with dietary polyphenols have also found improvements in insulin resistance. Recent studies suggest that the metabolic effects of curcumin/polyphenols are linked to changes in the gut microbiota. Thus, research into curcumin continues to provide novel insights into metabolic regulation that may ultimately translate into effective therapy.
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Affiliation(s)
- Tianru Jin
- Department of Physiology, University of Toronto , Toronto, Ontario , Canada
- Banting and Best Diabetes Centre, University of Toronto , Toronto, Ontario , Canada
- Division of Advanced Diagnostics, Toronto General Research Institute, University Health Network , Toronto, Ontario , Canada
| | - Zhuolun Song
- Department of Physiology, University of Toronto , Toronto, Ontario , Canada
- Division of Advanced Diagnostics, Toronto General Research Institute, University Health Network , Toronto, Ontario , Canada
| | - Jianping Weng
- Department of Endocrinology and Metabolism, Third Affiliated Hospital, Sun Yat-Sen University, Guangdong Sheng, China
| | - I George Fantus
- Department of Physiology, University of Toronto , Toronto, Ontario , Canada
- Banting and Best Diabetes Centre, University of Toronto , Toronto, Ontario , Canada
- Division of Advanced Diagnostics, Toronto General Research Institute, University Health Network , Toronto, Ontario , Canada
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital , Toronto, Ontario , Canada
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15
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Kawanishi N, Takagi K, Lee HC, Nakano D, Okuno T, Yokomizo T, Machida S. Endurance exercise training and high-fat diet differentially affect composition of diacylglycerol molecular species in rat skeletal muscle. Am J Physiol Regul Integr Comp Physiol 2018; 314:R892-R901. [PMID: 29443549 PMCID: PMC6032301 DOI: 10.1152/ajpregu.00371.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Insulin resistance of peripheral muscle is implicated in the etiology of metabolic syndrome in obesity. Although accumulation of glycerolipids, such as triacylglycerol and diacylglycerol (DAG), in muscle contributes to insulin resistance in obese individuals, endurance-trained athletes also have higher glycerolipid levels but normal insulin sensitivity. We hypothesized that the difference in insulin sensitivity of skeletal muscle between athletes and obese individuals stems from changes in fatty acid composition of accumulated lipids. Here, we evaluated the effects of intense endurance exercise and high-fat diet (HFD) on the accumulation and composition of lipid molecular species in rat skeletal muscle using a lipidomic approach. Sprague-Dawley female rats were randomly assigned to three groups and received either normal diet (ND) in sedentary conditions, ND plus endurance exercise training, or HFD in sedentary conditions. Rats were fed ND or HFD between 4 and 12 wk of age. Rats in the exercise group ran on a treadmill for 120 min/day, 5 days/wk, for 8 wk. Soleus muscle lipidomic profiles were obtained using liquid chromatography/tandem mass spectrometry. Total DAG levels, particularly those of palmitoleate-containing species, were increased in muscle by exercise training. However, whereas the total DAG level in the muscle was also increased by HFD, the levels of DAG molecular species containing palmitoleate were decreased by HFD. The concentration of phosphatidylethanolamine molecular species containing palmitoleate was increased by exercise but decreased by HFD. Our results indicate that although DAG accumulation was similar levels in trained and sedentary obese rats, specific changes in molecular species containing palmitoleate were opposite.
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Affiliation(s)
- Noriaki Kawanishi
- Graduate School of Health and Sports Science, Juntendo University, Inzai, Chiba, Japan.,Research Fellow of the Japan Society for the Promotion of Sciences , Tokyo , Japan.,Institute of Health and Sports Science and Medicine, Juntendo University, Inzai, Japan.,Faculty of Advanced Engineering, Chiba Institute of Technology, Narashino, Chiba, Japan
| | - Kana Takagi
- Graduate School of Health and Sports Science, Juntendo University, Inzai, Chiba, Japan
| | - Hyeon-Cheol Lee
- Department of Biochemistry, Graduate School of Medicine, Juntendo University , Tokyo , Japan
| | - Daiki Nakano
- Graduate School of Health and Sports Science, Juntendo University, Inzai, Chiba, Japan
| | - Toshiaki Okuno
- Department of Biochemistry, Graduate School of Medicine, Juntendo University , Tokyo , Japan
| | - Takehiko Yokomizo
- Department of Biochemistry, Graduate School of Medicine, Juntendo University , Tokyo , Japan
| | - Shuichi Machida
- Graduate School of Health and Sports Science, Juntendo University, Inzai, Chiba, Japan
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16
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Barreto R, Waning DL, Gao H, Liu Y, Zimmers TA, Bonetto A. Chemotherapy-related cachexia is associated with mitochondrial depletion and the activation of ERK1/2 and p38 MAPKs. Oncotarget 2017; 7:43442-43460. [PMID: 27259276 PMCID: PMC5190036 DOI: 10.18632/oncotarget.9779] [Citation(s) in RCA: 131] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 05/16/2016] [Indexed: 12/21/2022] Open
Abstract
Cachexia affects the majority of cancer patients, with currently no effective treatments. Cachexia is defined by increased fatigue and loss of muscle function resulting from muscle and fat depletion. Previous studies suggest that chemotherapy may contribute to cachexia, although the causes responsible for this association are not clear. The purpose of this study was to investigate the mechanism(s) associated with chemotherapy-related effects on body composition and muscle function. Normal mice were administered chemotherapy regimens used for the treatment of colorectal cancer, such as Folfox (5-FU, leucovorin, oxaliplatin) or Folfiri (5-FU, leucovorin, irinotecan) for 5 weeks. The animals that received chemotherapy exhibited concurrent loss of muscle mass and muscle weakness. Consistently with previous findings, muscle wasting was associated with up-regulation of ERK1/2 and p38 MAPKs. No changes in ubiquitin-dependent proteolysis or in the expression of TGFβ-family members were detected. Further, marked decreases in mitochondrial content, associated with abnormalities at the sarcomeric level and with increase in the number of glycolytic fibers were observed in the muscle of mice receiving chemotherapy. Finally, ACVR2B/Fc or PD98059 prevented Folfiri-associated ERK1/2 activation and myofiber atrophy in C2C12 cultures. Our findings demonstrate that chemotherapy promotes MAPK-dependent muscle atrophy as well as mitochondrial depletion and alterations of the sarcomeric units. Therefore, these findings suggest that chemotherapy potentially plays a causative role in the occurrence of muscle loss and weakness. Moreover, the present observations provide a strong rationale for testing ACVR2B/Fc or MEK1 inhibitors in combination with anticancer drugs as novel strategies aimed at preventing chemotherapy-associated muscle atrophy.
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Affiliation(s)
- Rafael Barreto
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - David L Waning
- Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA.,Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.,IUPUI Center for Cachexia Research, Innovation and Therapy, Indianapolis, IN 46202, USA
| | - Hongyu Gao
- Department of Medical and Molecular Genetics, Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yunlong Liu
- Department of Medical and Molecular Genetics, Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Teresa A Zimmers
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.,Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA.,IUPUI Center for Cachexia Research, Innovation and Therapy, Indianapolis, IN 46202, USA
| | - Andrea Bonetto
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.,Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA.,IUPUI Center for Cachexia Research, Innovation and Therapy, Indianapolis, IN 46202, USA
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17
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Menshikova EV, Ritov VB, Dube JJ, Amati F, Stefanovic-Racic M, Toledo FGS, Coen PM, Goodpaster BH. Calorie Restriction-induced Weight Loss and Exercise Have Differential Effects on Skeletal Muscle Mitochondria Despite Similar Effects on Insulin Sensitivity. J Gerontol A Biol Sci Med Sci 2017; 73:81-87. [PMID: 28158621 DOI: 10.1093/gerona/glw328] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 12/13/2016] [Indexed: 01/07/2023] Open
Abstract
Background Skeletal muscle insulin resistance and reduced mitochondrial capacity have both been reported to be affected by aging. The purpose of this study was to compare the effects of calorie restriction-induced weight loss and exercise on insulin resistance, skeletal muscle mitochondrial content, and mitochondrial enzyme activities in older overweight to obese individuals. Methods Insulin-stimulated rates of glucose disposal (Rd) were determined using the hyperinsulinemic euglycemic clamp before and after completing 16 weeks of either calorie restriction to induce weight loss (N = 7) or moderate exercise (N = 10). Mitochondrial volume density, mitochondria membrane content (cardiolipin), and activities of electron transport chain (rotenone-sensitive NADH-oxidase), tricarboxylic acid (TCA) cycle (citrate synthase) and β-oxidation pathway (β-hydroxyacyl CoA dehydrogenase; β-HAD) were measured in percutaneous biopsies of the vastus lateralis before and after the interventions. Results Rd improved similarly (18.2% ± 9.0%, p < .04) with both weight loss and exercise. Moderate exercise significantly increased mitochondrial volume density (14.5% ± 2.0%, p < .05), cardiolipin content (22.5% ± 13.4%, p < .05), rotenone-sensitive NADH-oxidase (65.7% ± 13.2%, p = .02) and β-HAD (30.7% ± 6.8%, p ≤ .03) activity, but not citrate synthase activity (10.1% ± 4.0%). In contrast, calorie restriction-induced weight loss did not affect mitochondrial content, NADH-oxidase or β-HAD, yet increased citrate synthase activity (44.1% ± 21.1%, p ≤ .04). Exercise (increase) or weight loss (decrease) induced a remodeling of cardiolipin with a small (2%-3%), but significant change in the relative content of tetralinoleoyl cardiolipin. Conclusion Exercise increases both mitochondria content and mitochondrial electron transport chain and fatty acid oxidation enzyme activities within skeletal muscle, while calorie restriction-induced weight loss did not, despite similar improvements in insulin sensitivity in overweight older adults.
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Affiliation(s)
- Elizaveta V Menshikova
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania
| | - Vladimir B Ritov
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania
| | - John J Dube
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania
| | - Francesca Amati
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania
| | - Maja Stefanovic-Racic
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania
| | - Frederico G S Toledo
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania
| | - Paul M Coen
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania.,Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Sanford-Burnham Medical Research Institute, Orlando
| | - Bret H Goodpaster
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pennsylvania.,Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Sanford-Burnham Medical Research Institute, Orlando
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18
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Montgomery MK, Brown SHJ, Mitchell TW, Coster ACF, Cooney GJ, Turner N. Association of muscle lipidomic profile with high-fat diet-induced insulin resistance across five mouse strains. Sci Rep 2017; 7:13914. [PMID: 29066734 PMCID: PMC5654831 DOI: 10.1038/s41598-017-14214-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/05/2017] [Indexed: 12/20/2022] Open
Abstract
Different mouse strains exhibit variation in their inherent propensities to develop metabolic disease. We recently showed that C57BL6, 129X1, DBA/2 and FVB/N mice are all susceptible to high-fat diet-induced glucose intolerance, while BALB/c mice are relatively protected, despite changes in many factors linked with insulin resistance. One parameter strongly linked with insulin resistance is ectopic lipid accumulation, especially metabolically active ceramides and diacylglycerols (DAG). This study examined diet-induced changes in the skeletal muscle lipidome across these five mouse strains. High-fat feeding increased total muscle triacylglycerol (TAG) content, with elevations in similar triacylglycerol species observed for all strains. There were also generally consistent changes across strains in the abundance of different phospholipid (PL) classes and the fatty acid profile of phospholipid molecular species, with the exception being a strain-specific difference in phospholipid species containing two polyunsaturated fatty acyl chains in BALB/c mice (i.e. a diet-induced decrease in the other four strains, but no change in BALB/c mice). In contrast to TAG and PL, the high-fat diet had a minor influence on DAG and ceramide species across all strains. These results suggest that widespread alterations in muscle lipids are unlikely a major contributors to the favourable metabolic profile of BALB/c mice and rather there is a relatively conserved high-fat diet response in muscle of most mouse strains.
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Affiliation(s)
- Magdalene K Montgomery
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
| | - Simon H J Brown
- School of Medicine, University of Wollongong, Wollongong, NSW, Australia
- llawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
| | - Todd W Mitchell
- School of Medicine, University of Wollongong, Wollongong, NSW, Australia
- llawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
| | - Adelle C F Coster
- School of Mathematics and Statistics, University of New South Wales, Sydney, NSW, Australia
| | - Gregory J Cooney
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Nigel Turner
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia.
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19
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Miotto PM, Horbatuk M, Proudfoot R, Matravadia S, Bakovic M, Chabowski A, Holloway GP. α-Linolenic acid supplementation and exercise training reveal independent and additive responses on hepatic lipid accumulation in obese rats. Am J Physiol Endocrinol Metab 2017; 312:E461-E470. [PMID: 28270444 PMCID: PMC5494579 DOI: 10.1152/ajpendo.00438.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/02/2017] [Accepted: 03/03/2017] [Indexed: 02/06/2023]
Abstract
α-Linolenic acid (ALA) supplementation or exercise training can independently prevent hepatic lipid accumulation and reduced insulin signaling; however, this may occur through different mechanisms of action. In the current study, obese Zucker rats displayed decreased phospholipid (PL) content in association with hepatic lipid abundance, and therefore, we examined whether ALA and exercise training would prevent these abnormalities differently to reveal additive effects on the liver. To achieve this aim, obese Zucker rats were fed control diet alone or supplemented with ALA and were sedentary or exercise trained for 4 wk (C-Sed, ALA-Sed, C-Ex, and ALA-Ex). ALA-Sed rats had increased microsomal-triglyceride transfer protein (MTTP), a protein required for lipoprotein assembly/secretion, as well as modestly increased PL content in the absence of improvements in mitochondrial content, lipid accumulation, or insulin sensitivity. In contrast, C-Ex rats had increased mitochondrial content and insulin sensitivity; however, this corresponded with minimal improvements in PL content and hepatic lipid accumulation. Importantly, ALA-Ex rats demonstrated additive improvements in PL content and hepatic steatosis, which corresponded with increased mitochondrial content, MTTP and apolipoprotein B100 content, greater serum triacylglyceride, and insulin sensitivity. Overall, these data demonstrate additive effects of ALA and exercise training on hepatic lipid accumulation, as exercise training preferentially increased mitochondrial content, while ALA promoted an environment conducive for lipid secretion. These data highlight the potential for combination therapy to mitigate liver disease progression.
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Affiliation(s)
- Paula M Miotto
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Meaghan Horbatuk
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Ross Proudfoot
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Sarthak Matravadia
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Marica Bakovic
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Adrian Chabowski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - Graham P Holloway
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
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20
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Nagarajan SR, Brandon AE, McKenna JA, Shtein HC, Nguyen TQ, Suryana E, Poronnik P, Cooney GJ, Saunders DN, Hoy AJ. Insulin and diet-induced changes in the ubiquitin-modified proteome of rat liver. PLoS One 2017; 12:e0174431. [PMID: 28329008 PMCID: PMC5362237 DOI: 10.1371/journal.pone.0174431] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/08/2017] [Indexed: 12/14/2022] Open
Abstract
Ubiquitin is a crucial post-translational modification regulating numerous cellular processes, but its role in metabolic disease is not well characterized. In this study, we identified the in vivo ubiquitin-modified proteome in rat liver and determined changes in this ubiquitome under acute insulin stimulation and high-fat and sucrose diet-induced insulin resistance. We identified 1267 ubiquitinated proteins in rat liver across diet and insulin-stimulated conditions, with 882 proteins common to all conditions. KEGG pathway analysis of these proteins identified enrichment of metabolic pathways, TCA cycle, glycolysis/gluconeogenesis, fatty acid metabolism, and carbon metabolism, with similar pathways altered by diet and insulin resistance. Thus, the rat liver ubiquitome is sensitive to diet and insulin stimulation and this is perturbed in insulin resistance.
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Affiliation(s)
- Shilpa R. Nagarajan
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Amanda E. Brandon
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent’s Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Jessie A. McKenna
- Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Harrison C. Shtein
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Thinh Q. Nguyen
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Eurwin Suryana
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
| | - Philip Poronnik
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Gregory J. Cooney
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent’s Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Darren N. Saunders
- Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
- * E-mail: (AJH); (DNS)
| | - Andrew J. Hoy
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
- * E-mail: (AJH); (DNS)
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21
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Huang S, Huang S, Wang X, Zhang Q, Liu J, Leng Y. Downregulation of lipin-1 induces insulin resistance by increasing intracellular ceramide accumulation in C2C12 myotubes. Int J Biol Sci 2017; 13:1-12. [PMID: 28123341 PMCID: PMC5264256 DOI: 10.7150/ijbs.17149] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 09/30/2016] [Indexed: 11/21/2022] Open
Abstract
Dysregulation of lipid metabolism in skeletal muscle is involved in the development of insulin resistance. Mutations in lipin-1, a key lipid metabolism regulator leads to significant systemic insulin resistance in fld mice. However, the function of lipin-1 on lipid metabolism and insulin sensitivity in skeletal muscle is still unclear. Herein we demonstrated that downregulation of lipin-1 in C2C12 myotubes by siRNA transfection suppressed insulin action, characterized by reduced insulin stimulated Akt phosphorylation and glucose uptake. Correspondingly, decreased lipin-1 expression was observed in palmitate-induced insulin resistance in C2C12 myotubes, suggested that lipin-1 might play a role in the etiology of insulin resistance in skeletal muscle. The insulin resistance induced by lipin-1 downregulation was related to the disturbance of lipid homeostasis. Lipin-1 silencing reduced intracellular DAG and TAG levels, but elevated ceramide accumulation in C2C12 myotubes. Moreover, the impaired insulin stimulated Akt phosphorylation and glucose uptake caused by lipin-1 silencing could be blocked by the pretreatment with SPT inhibitor myriocin, ceramide synthase inhibitor FB1, or PP2A inhibitor okadaic acid, suggested that the increased ceramide accumulation might be responsible for the development of insulin resistance induced by lipin-1 silencing in C2C12 myotubes. Meanwhile, decreased lipin-1 expression also impaired mitochondrial function in C2C12 myotubes. Therefore, our study suggests that lipin-1 plays an important role in lipid metabolism and downregulation of lipin-1 induces insulin resistance by increasing intracellular ceramide accumulation in C2C12 myotubes. These results offer a molecular insight into the role of lipin-1 in the development of insulin resistance in skeletal muscle.
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Affiliation(s)
- Shujuan Huang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zu Chong Zhi Road 555, Shanghai 201203, China.; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Suling Huang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zu Chong Zhi Road 555, Shanghai 201203, China
| | - Xi Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zu Chong Zhi Road 555, Shanghai 201203, China
| | - Qingli Zhang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zu Chong Zhi Road 555, Shanghai 201203, China
| | - Jia Liu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zu Chong Zhi Road 555, Shanghai 201203, China
| | - Ying Leng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zu Chong Zhi Road 555, Shanghai 201203, China
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22
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Montgomery MK, Brown SHJ, Lim XY, Fiveash CE, Osborne B, Bentley NL, Braude JP, Mitchell TW, Coster ACF, Don AS, Cooney GJ, Schmitz-Peiffer C, Turner N. Regulation of glucose homeostasis and insulin action by ceramide acyl-chain length: A beneficial role for very long-chain sphingolipid species. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1828-1839. [PMID: 27591968 DOI: 10.1016/j.bbalip.2016.08.016] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 08/18/2016] [Accepted: 08/29/2016] [Indexed: 12/13/2022]
Abstract
In a recent study, we showed that in response to high fat feeding C57BL/6, 129X1, DBA/2 and FVB/N mice all developed glucose intolerance, while BALB/c mice displayed minimal deterioration in glucose tolerance and insulin action. Lipidomic analysis of livers across these five strains has revealed marked strain-specific differences in ceramide (Cer) and sphingomyelin (SM) species with high-fat feeding; with increases in C16-C22 (long-chain) and reductions in C>22 (very long-chain) Cer and SM species observed in the four strains that developed HFD-induced glucose intolerance. Intriguingly, the opposite pattern was observed in sphingolipid species in BALB/c mice. These strain-specific changes in sphingolipid acylation closely correlated with ceramide synthase 2 (CerS2) protein content and activity, with reduced CerS2 levels/activity observed in glucose intolerant strains and increased content in BALB/c mice. Overexpression of CerS2 in primary mouse hepatocytes induced a specific elevation in very long-chain Cer, but despite the overall increase in ceramide abundance, there was a substantial improvement in insulin signal transduction, as well as decreased ER stress and gluconeogenic markers. Overall our findings suggest that very long-chain sphingolipid species exhibit a protective role against the development of glucose intolerance and hepatic insulin resistance.
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Affiliation(s)
- Magdalene K Montgomery
- Department of Pharmacology, School of Medical Sciences, UNSW Australia, Sydney, NSW, Australia
| | - Simon H J Brown
- School of Medicine, University of Wollongong, Wollongong, NSW, Australia; Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
| | - Xin Y Lim
- Prince of Wales Clinical School, UNSW Australia, Sydney, NSW, Australia
| | - Corrine E Fiveash
- Department of Pharmacology, School of Medical Sciences, UNSW Australia, Sydney, NSW, Australia
| | - Brenna Osborne
- Department of Pharmacology, School of Medical Sciences, UNSW Australia, Sydney, NSW, Australia
| | - Nicholas L Bentley
- Department of Pharmacology, School of Medical Sciences, UNSW Australia, Sydney, NSW, Australia
| | - Jeremy P Braude
- Department of Pharmacology, School of Medical Sciences, UNSW Australia, Sydney, NSW, Australia
| | - Todd W Mitchell
- School of Medicine, University of Wollongong, Wollongong, NSW, Australia; Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW, Australia
| | - Adelle C F Coster
- School of Mathematics and Statistics, UNSW Australia, Sydney, NSW, Australia
| | - Anthony S Don
- Prince of Wales Clinical School, UNSW Australia, Sydney, NSW, Australia
| | - Gregory J Cooney
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia; St Vincent's Clinical School, UNSW Australia, Sydney, NSW, Australia
| | - Carsten Schmitz-Peiffer
- Diabetes & Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia; St Vincent's Clinical School, UNSW Australia, Sydney, NSW, Australia
| | - Nigel Turner
- Department of Pharmacology, School of Medical Sciences, UNSW Australia, Sydney, NSW, Australia.
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Strekalova T, Costa-Nunes JP, Veniaminova E, Kubatiev A, Lesch KP, Chekhonin VP, Evans MC, Steinbusch HWM. Insulin receptor sensitizer, dicholine succinate, prevents both Toll-like receptor 4 (TLR4) upregulation and affective changes induced by a high-cholesterol diet in mice. J Affect Disord 2016; 196:109-16. [PMID: 26921863 DOI: 10.1016/j.jad.2016.02.045] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 02/03/2016] [Accepted: 02/16/2016] [Indexed: 12/26/2022]
Abstract
BACKGROUND High cholesterol intake in mice induces hepatic lipid dystrophy and inflammation, signs of non-alcoholic fatty liver disease (NAFLD), depressive- and anxiety-like behaviors, and the up-regulation of brain and liver Toll-like receptor 4 (Tlr4). Here, we investigated whether dicholine succinate (DS), an insulin receptor sensitizer and mitochondrial complex II substrate would interact with these effects. METHODS C57BL/6J mice were given a 0.2%-cholesterol diet for 3 weeks, alone or along with oral DS administration, or a control feed. Outcomes included behavioral measures of anxiety/depression, and Tlr4 and peroxisome-proliferator-activated-receptor-gamma coactivator-1b (PPARGC1b) expression. RESULTS 50mg/kg DS treatment for 3 weeks partially ameliorated the cholesterol-induced anxiety- and depressive-like changes. Mice were next treated at the higher dose (180mg/kg), either for the 3-week period of dietary intervention, or for the last two weeks. Three-week DS administration normalized behaviors in the forced swim and O-maze tests and abolished the Tlr4 up-regulation in the brain and liver. The delayed, 2-week DS treatment had similar effects on Tlr4 expression and largely rescued the above-mentioned behaviors. Suppression of PPARGC1b, a master regulator of mitochondrial biogenesis, by the high cholesterol diet, was prevented with the 3-week administration, and markedly diminished by the a 2-week administration of DS. None of treatments prevented hepatic dystrophy and triglyceride accumulation. LIMITATIONS Other conditions have to be tested to define possible limitations of reported effects of DS. CONCLUSIONS DS treatment did not alter the patho-morphological substrates of NAFLD syndrome in mice, but ameliorated its molecular and behavioral consequences, likely by activating mitochondrial functions and anti-inflammatory mechanisms.
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Affiliation(s)
- Tatyana Strekalova
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Universiteitssingel 40, 6200 MD Maastricht, The Netherlands.
| | - João P Costa-Nunes
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Universiteitssingel 40, 6200 MD Maastricht, The Netherlands; CEDOC, NOVA Medical School, Faculdade de Ciências Médicas, FCM, Universidade Nova de Lisboa, Campo Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
| | - Ekaterina Veniaminova
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Universiteitssingel 40, 6200 MD Maastricht, The Netherlands; Institute of General Pathology and Pathophysiology, Russian Academy of Medical Sciences, Baltiyskaya 8, Moscow 125315, Russia
| | - Aslan Kubatiev
- Institute of General Pathology and Pathophysiology, Russian Academy of Medical Sciences, Baltiyskaya 8, Moscow 125315, Russia
| | - Klaus-Peter Lesch
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Universiteitssingel 40, 6200 MD Maastricht, The Netherlands; Division of Molecular Psychiatry, Laboratory of Translational Neuroscience, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Wuerzburg, Fuechsleinstr. 15, 97080 Wuerzburg, Germany
| | - Vladimir P Chekhonin
- Serbsky National Research Center for Social and Forensic Psychiatry, Department of Fundamental and Applied Neurobiology, per. Kropotkin 23, Moscow 119034, Russian Federation
| | - Matthew C Evans
- Department of Pharmacology, Oxford University, Mansfield Road, OX1 3QT Oxford, UK
| | - Harry W M Steinbusch
- Department of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Universiteitssingel 40, 6200 MD Maastricht, The Netherlands
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24
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Matravadia S, Zabielski P, Chabowski A, Mutch DM, Holloway GP. LA and ALA prevent glucose intolerance in obese male rats without reducing reactive lipid content, but cause tissue-specific changes in fatty acid composition. Am J Physiol Regul Integr Comp Physiol 2016; 310:R619-30. [PMID: 26764053 DOI: 10.1152/ajpregu.00297.2015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 01/12/2016] [Indexed: 12/18/2022]
Abstract
While the cause of Type 2 diabetes remains poorly defined, the accumulation of reactive lipids within white adipose tissue, skeletal muscle, and liver have been repeatedly implicated as underlying mechanisms. The ability of polyunsaturated fatty acids (PUFAs) to prevent the development of insulin resistance has gained considerable interest in recent years; however, the mechanisms-of-action remain poorly described. Therefore, we determined the efficacy of diets supplemented with either linoleic acid (LA) or α-linolenic acid (ALA) in preventing insulin resistance and reactive lipid accumulation in key metabolic tissues of the obese Zucker rat. Obese Zucker rats displayed impaired glucose homeostasis and reduced n-3 and n-6 PUFA content in the liver and epididymal white adipose tissue (EWAT). After the 12-wk feeding intervention, both LA- and ALA-supplemented diets prevented whole body glucose and insulin intolerance; however, ALA had a more pronounced effect. These changes occurred in association with n-3 and n-6 accumulation in all tissues studied, albeit to different extents (EWAT > liver > muscle). Triacylglycerol (TAG), diacylglycerol (DAG), ceramide, and sphingolipid accumulation were not attenuated in obese animals supplemented with either LA or ALA, suggesting that preservation of glucose homeostasis occurred independent of changes in reactive lipid content. However, PUFA-supplemented diets differentially altered the fatty acid composition of TAGs, DAGs, and PLs in a tissue-specific manner, suggesting essential fatty acid metabolism differs between tissues. Together, our results indicate that remodeling of the fatty acid composition of various lipid fractions may contribute to the improved glucose tolerance observed in obese rats fed PUFA-supplemented diets.
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Affiliation(s)
- Sarthak Matravadia
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Piotr Zabielski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - Adrian Chabowski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - David M Mutch
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Graham P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada;
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25
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Akerstrom T, Vedel K, Needham J, Hojman P, Kontou E, Hellsten Y, Wojtaszewski JF. Optimizing hyaluronidase dose and plasmid DNA delivery greatly improves gene electrotransfer efficiency in rat skeletal muscle. Biochem Biophys Rep 2015; 4:342-350. [PMID: 29124223 PMCID: PMC5669402 DOI: 10.1016/j.bbrep.2015.10.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Revised: 10/12/2015] [Accepted: 10/20/2015] [Indexed: 11/18/2022] Open
Abstract
Transfection of rat skeletal muscle in vivo is a widely used research model. However, gene electrotransfer protocols have been developed for mice and yield variable results in rats. We investigated whether changes in hyaluronidase pre-treatment and plasmid DNA delivery can improve transfection efficiency in rat skeletal muscle. We found that pre-treating the muscle with a hyaluronidase dose suitable for rats (0.56 U/g b.w.) prior to plasmid DNA injection increased transfection efficiency by >200% whereas timing of the pre-treatment did not affect efficiency. Uniformly distributing plasmid DNA delivery across the muscle by increasing the number of plasmid DNA injections further enhanced transfection efficiency whereas increasing plasmid dose from 0.2 to 1.6 µg/g b.w. or vehicle volume had no effect. The optimized protocol resulted in ~80% (CI95%: 79–84%) transfected muscle fibers with a homogenous distribution. We also show that transfection was stable over five weeks of regular exercise or inactivity. Our findings show that species-specific plasmid DNA delivery and hyaluronidase pre-treatment greatly improves transfection efficiency in rat skeletal muscle. Parameters for effective in vivo skeletal muscle transfection are species specific. Pre-treatment with a rat-specific hyaluronidase dose greatly improves transfection efficiency. Delivering plasmid DNA more uniformly enhances transfection efficiency in rat skeletal muscle. Transfection efficiency is not improved by increasing plasmid DNA dose. Exercise training does not affect transfection stability.
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Affiliation(s)
- Thorbjorn Akerstrom
- The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
- Correspondence to: The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Universitetsparken 13, DK-2100 Copenhagen, Denmark. Fax: +4535320870.The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of CopenhagenUniversitetsparken 13CopenhagenDK-2100Denmark
| | - Kenneth Vedel
- The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Josefine Needham
- The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Pernille Hojman
- Centre of Inflammation and Metabolism, Centre for Physical Activity Research, Copenhagen University Hospital, Copenhagen, Denmark
| | - Eftychia Kontou
- The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Ylva Hellsten
- The August Krogh Centre, Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Jørgen F.P. Wojtaszewski
- The August Krogh Centre, Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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26
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Ludzki A, Paglialunga S, Smith BK, Herbst EAF, Allison MK, Heigenhauser GJ, Neufer PD, Holloway GP. Rapid Repression of ADP Transport by Palmitoyl-CoA Is Attenuated by Exercise Training in Humans: A Potential Mechanism to Decrease Oxidative Stress and Improve Skeletal Muscle Insulin Signaling. Diabetes 2015; 64:2769-79. [PMID: 25845660 PMCID: PMC4876790 DOI: 10.2337/db14-1838] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 03/28/2015] [Indexed: 12/11/2022]
Abstract
Mitochondrial ADP transport may represent a convergence point unifying two prominent working models for the development of insulin resistance, as reactive lipids (specifically palmitoyl-CoA [P-CoA]) can inhibit ADP transport and subsequently increase mitochondrial reactive oxygen species emissions. In the current study, we aimed to determine if exercise training in humans diminished P-CoA attenuation of mitochondrial ADP respiratory sensitivity. Six weeks of exercise training increased whole-body glucose homeostasis and skeletal muscle Akt signaling and reduced markers of oxidative stress without reducing maximal mitochondrial H2O2 emissions. To ascertain if enhanced mitochondrial ADP transport contributed to the improvement in the in vivo oxidative state, we determined mitochondrial ADP sensitivity in the presence and absence of P-CoA. In the absence of P-CoA, exercise training reduced mitochondrial ADP sensitivity. In contrast, exercise training increased mitochondrial ADP sensitivity with P-CoA present. We further show that P-CoA noncompetitively inhibits mitochondrial ADP transport and the ability of ADP to attenuate mitochondrial H2O2 emission. Altogether, the current data provide a potential mechanism for how P-CoA contributes to insulin resistance and highlight the ability of exercise training to diminish P-CoA attenuation in mitochondrial ADP transport.
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Affiliation(s)
- Alison Ludzki
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Sabina Paglialunga
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Brennan K Smith
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Eric A F Herbst
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Mary K Allison
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | | | - P Darrell Neufer
- East Carolina Diabetes and Obesity Institute, Departments of Physiology and Kinesiology, East Carolina University, Greenville, NC
| | - Graham P Holloway
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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27
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Zamora M, Pardo R, Villena JA. Pharmacological induction of mitochondrial biogenesis as a therapeutic strategy for the treatment of type 2 diabetes. Biochem Pharmacol 2015. [PMID: 26212547 DOI: 10.1016/j.bcp.2015.06.032] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Defects in mitochondrial oxidative function have been associated with the onset of type 2 diabetes. Although the causal relationship between mitochondrial dysfunction and diabetes has not been fully established, numerous studies indicate that improved glucose homeostasis achieved via lifestyle interventions, such as exercise or calorie restriction, is tightly associated with increased mitochondrial biogenesis and oxidative function. Therefore, it is conceivable that potentiating mitochondrial biogenesis by pharmacological means could constitute an efficacious therapeutic strategy that would particularly benefit those diabetic patients who cannot adhere to comprehensive programs based on changes in lifestyle or that require a relatively rapid improvement in their diabetic status. In this review, we discuss several pharmacological targets and drugs that modulate mitochondrial biogenesis as well as their potential use as treatments for insulin resistance and diabetes.
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Affiliation(s)
- Mònica Zamora
- Cell Biology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, CIBER on Neurodegenerative Diseases (CIBERNED), Barcelona, Spain
| | - Rosario Pardo
- Laboratory of Metabolism and Obesity, Vall d'Hebron-Institut de Recerca, Universitat Autònoma de Barcelona, CIBER on Diabetes and Associated Metabolic Diseases (CIBERDEM), Barcelona, Spain
| | - Josep A Villena
- Laboratory of Metabolism and Obesity, Vall d'Hebron-Institut de Recerca, Universitat Autònoma de Barcelona, CIBER on Diabetes and Associated Metabolic Diseases (CIBERDEM), Barcelona, Spain.
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28
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Brandon AE, Tid-Ang J, Wright LE, Stuart E, Suryana E, Bentley N, Turner N, Cooney GJ, Ruderman NB, Kraegen EW. Overexpression of SIRT1 in rat skeletal muscle does not alter glucose induced insulin resistance. PLoS One 2015; 10:e0121959. [PMID: 25798922 PMCID: PMC4370576 DOI: 10.1371/journal.pone.0121959] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 02/10/2015] [Indexed: 12/17/2022] Open
Abstract
SIRT1 is a NAD+-dependent deacetylase thought to regulate cellular metabolic pathways in response to alterations in nutrient flux. In the current study we investigated whether acute changes in SIRT1 expression affect markers of muscle mitochondrial content and also determined whether SIRT1 influenced muscle insulin resistance induced by acute glucose oversupply. In male Wistar rats either SIRT1 or a deacetylase inactive mutant form (H363Y) was electroprated into the tibialis cranialis (TC) muscle. The other leg was electroporated with an empty control vector. One week later, glucose was infused and hyperglycaemia was maintained at ~11mM. After 5 hours, 11mM glucose induced significant insulin resistance in skeletal muscle. Interestingly, overexpression of either SIRT1 or SIRT1 (H363Y) for 1 week did not change markers of mitochondrial content or function. SIRT1 or SIRT1 (H363Y) overexpression had no effect on the reduction in glucose uptake and glycogen synthesis in muscle in response to hyperglycemia. Therefore we conclude that acute increases in SIRT1 protein have little impact on mitochondrial content and that overexpressing SIRT1 does not prevent the development of insulin resistance during hyperglycaemia.
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Affiliation(s)
- Amanda E Brandon
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia
| | - Jennifer Tid-Ang
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia
| | - Lauren E Wright
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia
| | - Ella Stuart
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia
| | - Eurwin Suryana
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia
| | | | - Nigel Turner
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia; UNSW Medicine, University of New South Wales, Sydney, Australia
| | - Gregory J Cooney
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia; UNSW Medicine, University of New South Wales, Sydney, Australia
| | - Neil B Ruderman
- Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Edward W Kraegen
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, 384 Victoria St., Darlinghurst, NSW, 2010, Australia; UNSW Medicine, University of New South Wales, Sydney, Australia
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29
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Zhang HH, Qin GJ, Li XL, Zhang YH, Du PJ, Zhang PY, Zhao YY, Wu J. SIRT1 overexpression in skeletal muscle in vivo induces increased insulin sensitivity and enhanced complex I but not complex II-V functions in individual subsarcolemmal and intermyofibrillar mitochondria. J Physiol Biochem 2015; 71:177-90. [PMID: 25782776 DOI: 10.1007/s13105-015-0396-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 02/20/2015] [Indexed: 01/04/2023]
Abstract
SIRT1 is known to improve insulin resistance (IR), but whether this effect is direct or not is still unclear, and this question has not been addressed in vivo in the skeletal muscle. Therefore, we sought to test if acute overexpression of SIRT1 in skeletal muscle of high-fat diet (HFD) rats in vivo would affect subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondrial complexes I-V activities and antioxidant enzymes thereby improving insulin action. In vivo electrotransfer was used to overexpress SIRT1 in the skeletal muscle of rats fed HFD for 12 weeks. Skeletal muscle insulin sensitivity and downstream effects of SIRT1 on AMPK, SIRT3, and mitochondrial biogenesis were studied. Citrate synthase (CS), complexes I-V, oxidative stress, and antioxidant levels were assessed in SS and IMF mitochondria. HFD rats showed skeletal muscle IR as well as decreased SIRT1 and SIRT3 expressions, mitochondrial DNA (mtDNA), and mitochondrial biogenesis (p < 0.05). SS and IMF mitochondria displayed lower CS, complexes I-V, and antioxidant enzyme activities (p < 0.05). By contrast, moderate (~2.5 folds) SIRT1 overexpression attenuated HFD-induced skeletal muscle IR. This improvement was associated with increased AMPK, PGC-1α, SIRT3, and mtDNA expressions as well as SS and IMF mitochondrial CS and complexes I-V activities. Importantly, SIRT1 overexpression largely restored antioxidant enzyme activities and enhanced complex I but not complexes II-V functions in individual SS and IMF mitochondria. This study suggests that SIRT1 overexpression improved IR at least partly by targeting complex I functions of SS and IMF mitochondria through the activation of SIRT1 and SIRT3.
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Affiliation(s)
- Hao-Hao Zhang
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, 40 Daxue Road, 450052, Zhengzhou, China
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30
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Montgomery MK, Turner N. Mitochondrial dysfunction and insulin resistance: an update. Endocr Connect 2015; 4:R1-R15. [PMID: 25385852 PMCID: PMC4261703 DOI: 10.1530/ec-14-0092] [Citation(s) in RCA: 354] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 11/10/2014] [Indexed: 12/11/2022]
Abstract
Mitochondrial dysfunction has been implicated in the development of insulin resistance (IR); however, a large variety of association and intervention studies as well as genetic manipulations in rodents have reported contrasting results. Indeed, even 39 years after the first publication describing a relationship between IR and diminished mitochondrial function, it is still unclear whether a direct relationship exists, and more importantly if changes in mitochondrial capacity are a cause or consequence of IR. This review will take a journey through the past and summarise the debate about the occurrence of mitochondrial dysfunction and its possible role in causing decreased insulin action in obesity and type 2 diabetes. Evidence is presented from studies in various human populations, as well as rodents with genetic manipulations of pathways known to affect mitochondrial function and insulin action. Finally, we have discussed whether mitochondria are a potential target for the treatment of IR.
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Affiliation(s)
- Magdalene K Montgomery
- Department of PharmacologyUNSW Medicine, School of Medical Sciences, University of New South Wales, Kensington, Sydney, New South Wales 2052, Australia
| | - Nigel Turner
- Department of PharmacologyUNSW Medicine, School of Medical Sciences, University of New South Wales, Kensington, Sydney, New South Wales 2052, Australia
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31
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Resveratrol improves high-fat diet induced insulin resistance by rebalancing subsarcolemmal mitochondrial oxidation and antioxidantion. J Physiol Biochem 2015; 71:121-31. [DOI: 10.1007/s13105-015-0392-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 02/06/2015] [Indexed: 12/29/2022]
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32
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Villena JA. New insights into PGC-1 coactivators: redefining their role in the regulation of mitochondrial function and beyond. FEBS J 2015; 282:647-72. [DOI: 10.1111/febs.13175] [Citation(s) in RCA: 252] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/31/2014] [Accepted: 12/10/2014] [Indexed: 12/25/2022]
Affiliation(s)
- Josep A. Villena
- Laboratory of Metabolism and Obesity; Vall d'Hebron-Institut de Recerca; Universitat Autònoma de Barcelona; Spain
- CIBERDEM (CIBER de Diabetes y Enfermedades Metabólicas Asociadas); Instituto de Salud Carlos III; Barcelona Spain
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33
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Williams LM, Campbell FM, Drew JE, Koch C, Hoggard N, Rees WD, Kamolrat T, Thi Ngo H, Steffensen IL, Gray SR, Tups A. The development of diet-induced obesity and glucose intolerance in C57BL/6 mice on a high-fat diet consists of distinct phases. PLoS One 2014; 9:e106159. [PMID: 25170916 PMCID: PMC4149520 DOI: 10.1371/journal.pone.0106159] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 06/19/2014] [Indexed: 02/06/2023] Open
Abstract
High-fat (HF) diet-induced obesity and insulin insensitivity are associated with inflammation, particularly in white adipose tissue (WAT). However, insulin insensitivity is apparent within days of HF feeding when gains in adiposity and changes in markers of inflammation are relatively minor. To investigate further the effects of HF diet, C57Bl/6J mice were fed either a low (LF) or HF diet for 3 days to 16 weeks, or fed the HF-diet matched to the caloric intake of the LF diet (PF) for 3 days or 1 week, with the time course of glucose tolerance and inflammatory gene expression measured in liver, muscle and WAT. HF fed mice gained adiposity and liver lipid steadily over 16 weeks, but developed glucose intolerance, assessed by intraperitoneal glucose tolerance tests (IPGTT), in two phases. The first phase, after 3 days, resulted in a 50% increase in area under the curve (AUC) for HF and PF mice, which improved to 30% after 1 week and remained stable until 12 weeks. Between 12 and 16 weeks the difference in AUC increased to 60%, when gene markers of inflammation appeared in WAT and muscle but not in liver. Plasma proteomics were used to reveal an acute phase response at day 3. Data from PF mice reveals that glucose intolerance and the acute phase response are the result of the HF composition of the diet and increased caloric intake respectively. Thus, the initial increase in glucose intolerance due to a HF diet occurs concurrently with an acute phase response but these effects are caused by different properties of the diet. The second increase in glucose intolerance occurs between 12-16 weeks of HF diet and is correlated with WAT and muscle inflammation. Between these times glucose tolerance remains stable and markers of inflammation are undetectable.
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Affiliation(s)
- Lynda M. Williams
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
- * E-mail:
| | - Fiona M. Campbell
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Janice E. Drew
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Christiane Koch
- Department of Animal Physiology, Faculty of Biology, Philipps University Marburg, Marburg, Germany
| | - Nigel Hoggard
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - William D. Rees
- Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, United Kingdom
| | - Torkamol Kamolrat
- Musculoskeletal Research Programme, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Ha Thi Ngo
- Department of Food, Water and Cosmetics, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
| | - Inger-Lise Steffensen
- Department of Food, Water and Cosmetics, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway
| | - Stuart R. Gray
- Musculoskeletal Research Programme, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Alexander Tups
- Department of Animal Physiology, Faculty of Biology, Philipps University Marburg, Marburg, Germany
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Holloway GP, Han XX, Jain SS, Bonen A, Chabowski A. Chronic muscle stimulation improves insulin sensitivity while increasing subcellular lipid droplets and reducing selected diacylglycerol and ceramide species in obese Zucker rats. Diabetologia 2014; 57:832-40. [PMID: 24458200 DOI: 10.1007/s00125-014-3169-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 01/02/2014] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS Although insulin resistance has been associated with accumulations of specific intramuscular fatty acids and altered subcellular localisation of lipid droplets, these concepts remain controversial. Therefore, we aimed to identify specific intramuscular fatty acids and subcellular lipid localisations associated with improved insulin sensitivity following chronic muscle contraction. METHODS In lean and insulin-resistant obese Zucker rats the tibialis anterior muscle was stimulated (6 h/day for 6 days). Thereafter, muscles were examined for insulin sensitivity, intramuscular lipid droplet localisation and triacylglycerol (TAG), diacylglycerol (DAG) and ceramide fatty acid composition. RESULTS In lean and obese animals, regardless of muscle type, chronic muscle contraction improved muscle insulin sensitivity and increased intramuscular levels of total and most C14-C22 TAG fatty acids (p < 0.05). Therefore, accumulation in subcellular lipid droplet compartments reflected the oversupply of lipids within muscle. In contrast, improvements in insulin sensitivity induced by muscle contraction were associated with reductions in specific DAG and ceramide species that were not uniform in red and white muscle of obese rats. However, these reductions were insufficient to fully normalise insulin sensitivity, indicating that other mechanisms are involved. CONCLUSIONS/INTERPRETATION Reductions in 18 C length DAG and ceramide species were the most consistent in red and white muscle and therefore may represent therapeutic targets for improving insulin sensitivity.
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Affiliation(s)
- Graham P Holloway
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, NIG, 2W1,
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Mitochondrial stress signaling promotes cellular adaptations. Int J Cell Biol 2014; 2014:156020. [PMID: 24587804 PMCID: PMC3920668 DOI: 10.1155/2014/156020] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 11/11/2013] [Indexed: 01/06/2023] Open
Abstract
Mitochondrial dysfunction has been implicated in the aetiology of many complex diseases, as well as the ageing process. Much of the research on mitochondrial dysfunction has focused on how mitochondrial damage may potentiate pathological phenotypes. The purpose of this review is to draw attention to the less well-studied mechanisms by which the cell adapts to mitochondrial perturbations. This involves communication of stress to the cell and successful induction of quality control responses, which include mitophagy, unfolded protein response, upregulation of antioxidant and DNA repair enzymes, morphological changes, and if all else fails apoptosis. The mitochondrion is an inherently stressful environment and we speculate that dysregulation of stress signaling or an inability to switch on these adaptations during times of mitochondrial stress may underpin mitochondrial dysfunction and hence amount to pathological states over time.
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Song GY, Ren LP, Chen SC, Wang C, Liu N, Wei LM, Li F, Sun W, Peng LB, Tang Y. Similar changes in muscle lipid metabolism are induced by chronic high-fructose feeding and high-fat feeding in C57BL/J6 mice. Clin Exp Pharmacol Physiol 2014; 39:1011-8. [PMID: 23039229 DOI: 10.1111/1440-1681.12017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 09/14/2012] [Accepted: 09/30/2012] [Indexed: 01/08/2023]
Abstract
The aim of the present study was to investigate the effects of high fructose and high fat feeding on muscle lipid metabolism and to illustrate the mechanisms by which the two different dietary factors induce muscle lipid accumulation. C57BL/J6 mice were fed either a standard, high-fructose (HFru) or high-fat diet. After 16 weeks feeding, mice were killed and plasma triglyceride (TG) and free fatty acid (FFA) levels were detected. In addition, muscle TG and long chain acyl CoA (LCACoA) content was determined, glucose tolerance was evaluated and the protein content of fatty acid translocase CD36 (FATCD36) in muscle was measured. Mitochondrial oxidative function in the muscle was evaluated by estimating the activity of oxidative enzymes, namely cytochrome oxidase (COx), citrate synthase (CS) and β-hydroxyacyl CoA dehydrogenase (β-HAD), and the muscle protein content of carnitine palmitoyltransferase-1 (CPT-1), cyclo-oxygenase (COX)-1 and proliferator-activated receptor coactivator (PGC)-1α was determined. Finally, sterol regulatory element-binding protein-1c (SREBP-1c) gene expression and fatty acid synthase (FAS) protein content were determined in muscle tissues. After 16 weeks, plasma TG and FFA levels were significantly increased in both the HFru and HF groups. In addition, mice in both groups exhibited significant increases in muscle TG and LCACoA content. Compared with mice fed the standard diet (control group), those in the HFru and HF groups developed glucose intolerance and exhibited increased FATCD36 protein levels, enzyme activity related to fatty acid utilization in the mitochondria and protein expressions of CPT-1, COX-1 and PGC-1α in muscle tissue. Finally, mice in both the HFru and HF groups exhibited increase SREBP-1c expression and FAS protein content. In conclusion, high fructose and high fat feeding lead to similar changes in muscle lipid metabolism in C57BL/J6 mice. Lipid accumulation in the muscle may be associated with increased expression of proteins related to lipid transportation and synthesis.
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Affiliation(s)
- Guang-Yao Song
- Department of Endocrinology, General Hospital of Hebei, Hebei, China.
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Zhang C, Klett EL, Coleman RA. Lipid signals and insulin resistance. CLINICAL LIPIDOLOGY 2013; 8:659-667. [PMID: 24533033 PMCID: PMC3921899 DOI: 10.2217/clp.13.67] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The metabolic syndrome, a cluster of metabolic derangements that include obesity, glucose intolerance, dyslipidemia and hypertension, is a major risk factor for cardiovascular disease. Insulin resistance has been proposed to be the common feature that links obesity to the metabolic syndrome, but the mechanism remains obscure. Although the excess content of triacylglycerol in muscle and liver is highly associated with insulin resistance in these tissues, triacylglycerol itself is not causal but merely a marker. Thus, attention has turned to the accumulation of cellular lipids known to have signaling roles. This review will discuss recent progress in understanding how glycerolipids and related lipid intermediates may impair insulin signaling.
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Affiliation(s)
- Chongben Zhang
- Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Eric L Klett
- Department of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Rosalind A Coleman
- Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA
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Montgomery MK, Osborne B, Brown SHJ, Small L, Mitchell TW, Cooney GJ, Turner N. Contrasting metabolic effects of medium- versus long-chain fatty acids in skeletal muscle. J Lipid Res 2013; 54:3322-33. [PMID: 24078708 DOI: 10.1194/jlr.m040451] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Dietary intake of long-chain fatty acids (LCFAs) plays a causative role in insulin resistance and risk of diabetes. Whereas LCFAs promote lipid accumulation and insulin resistance, diets rich in medium-chain fatty acids (MCFAs) have been associated with increased oxidative metabolism and reduced adiposity, with few deleterious effects on insulin action. The molecular mechanisms underlying these differences between dietary fat subtypes are poorly understood. To investigate this further, we treated C2C12 myotubes with various LCFAs (16:0, 18:1n9, and 18:2n6) and MCFAs (10:0 and 12:0), as well as fed mice diets rich in LCFAs or MCFAs, and investigated fatty acid-induced changes in mitochondrial metabolism and oxidative stress. MCFA-treated cells displayed less lipid accumulation, increased mitochondrial oxidative capacity, and less oxidative stress than LCFA-treated cells. These changes were associated with improved insulin action in MCFA-treated myotubes. MCFA-fed mice exhibited increased energy expenditure, reduced adiposity, and better glucose tolerance compared with LCFA-fed mice. Dietary MCFAs increased respiration in isolated mitochondria, with a simultaneous reduction in reactive oxygen species generation, and subsequently low oxidative damage. Collectively our findings indicate that in contrast to LCFAs, MCFAs increase the intrinsic respiratory capacity of mitochondria without increasing oxidative stress. These effects potentially contribute to the beneficial metabolic actions of dietary MCFAs.
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Affiliation(s)
- Magdalene K Montgomery
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
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Effect of ethyl pyruvate on skeletal muscle metabolism in rats fed on a high fat diet. Nutrients 2013; 5:2372-83. [PMID: 23857218 PMCID: PMC3738978 DOI: 10.3390/nu5072372] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 06/09/2013] [Accepted: 06/14/2013] [Indexed: 01/27/2023] Open
Abstract
Impaired mitochondrial capacity may be implicated in the pathology of chronic metabolic diseases. To elucidate the effect of ethyl pyruvate supplementation on skeletal muscles metabolism we examined changes in activities of mitochondrial and antioxidant enzymes, as well as sulfhydryl groups oxidation (an indirect marker of oxidative stress) during the development of obesity. After 6 weeks feeding of control or high fat diet, Wistar rats were divided into four groups: control diet, control diet and ethyl pyruvate, high fat diet, and high fat diet and ethyl pyruvate. Ethyl pyruvate was administered as 0.3% solution in drinking water, for the following 6 weeks. High fat diet feeding induced the increase of activities 3-hydroxyacylCoA dehydrogenase, citrate synthase, and fumarase. Moreover, higher catalase and superoxide dismutase activities, as well as sulfhydryl groups oxidation, were noted. Ethyl pyruvate supplementation did not affect the mitochondrial enzymes’ activities, but induced superoxide dismutase activity and sulfhydryl groups oxidation. All of the changes were observed in soleus muscle, but not in extensor digitorum longus muscle. Additionally, positive correlations between fasting blood insulin concentration and activities of catalase (p = 0.04), and superoxide dismutase (p = 0.01) in soleus muscle were noticed. Prolonged ethyl pyruvate consumption elevated insulin concentration, which may cause modifications in oxidative type skeletal muscles.
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Turner N, Kowalski GM, Leslie SJ, Risis S, Yang C, Lee-Young RS, Babb JR, Meikle PJ, Lancaster GI, Henstridge DC, White PJ, Kraegen EW, Marette A, Cooney GJ, Febbraio MA, Bruce CR. Distinct patterns of tissue-specific lipid accumulation during the induction of insulin resistance in mice by high-fat feeding. Diabetologia 2013; 56:1638-48. [PMID: 23620060 DOI: 10.1007/s00125-013-2913-1] [Citation(s) in RCA: 317] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 03/27/2013] [Indexed: 12/22/2022]
Abstract
AIMS/HYPOTHESIS While it is well known that diet-induced obesity causes insulin resistance, the precise mechanisms underpinning the initiation of insulin resistance are unclear. To determine factors that may cause insulin resistance, we have performed a detailed time-course study in mice fed a high-fat diet (HFD). METHODS C57Bl/6 mice were fed chow or an HFD from 3 days to 16 weeks and glucose tolerance and tissue-specific insulin action were determined. Tissue lipid profiles were analysed by mass spectrometry and inflammatory markers were measured in adipose tissue, liver and skeletal muscle. RESULTS Glucose intolerance developed within 3 days of the HFD and did not deteriorate further in the period to 12 weeks. Whole-body insulin resistance, measured by hyperinsulinaemic-euglycaemic clamp, was detected after 1 week of HFD and was due to hepatic insulin resistance. Adipose tissue was insulin resistant after 1 week, while skeletal muscle displayed insulin resistance at 3 weeks, coinciding with a defect in glucose disposal. Interestingly, no further deterioration in insulin sensitivity was observed in any tissue after this initial defect. Diacylglycerol content was increased in liver and muscle when insulin resistance first developed, while the onset of insulin resistance in adipose tissue was associated with increases in ceramide and sphingomyelin. Adipose tissue inflammation was only detected at 16 weeks of HFD and did not correlate with the induction of insulin resistance. CONCLUSIONS/INTERPRETATION HFD-induced whole-body insulin resistance is initiated by impaired hepatic insulin action and exacerbated by skeletal muscle insulin resistance and is associated with the accumulation of specific bioactive lipid species.
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Affiliation(s)
- N Turner
- Diabetes & Obesity Research Program, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW, Australia
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Roles of Fatty Acid oversupply and impaired oxidation in lipid accumulation in tissues of obese rats. J Lipids 2013; 2013:420754. [PMID: 23762564 PMCID: PMC3666279 DOI: 10.1155/2013/420754] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/19/2013] [Indexed: 12/30/2022] Open
Abstract
To test the roles of lipid oversupply versus oxidation in causing tissue lipid accumulation associated with insulin resistance/obesity, we studied in vivo fatty acid (FA) metabolism in obese (Obese) and lean (Lean) Zucker rats. Indices of local FA utilization and storage were calculated using the partially metabolizable [9,10-3H]-(R)-2-bromopalmitate (3H-R-BrP) and [U-14C]-palmitate (14C-P) FA tracers, respectively. Whole-body FA appearance (Ra) was estimated from plasma 14C-P kinetics. Whole-body FA oxidation rate (Rox) was assessed using 3H2O production from 3H-palmitate infusion, and tissue FA oxidative capacity was evaluated ex vivo. In the basal fasting state Obese had markedly elevated FA levels and Ra, associated with elevated FA utilization and storage in most tissues. Estimated rates of muscle FA oxidation were not lower in obese rats and were similarly enhanced by contraction in both lean and obese groups. At comparable levels of FA availability, achieved by nicotinic acid, Rox was lower in Obese than Lean. In Obese rats, FA oxidative capacity was 35% higher than that in Lean in skeletal muscle, 67% lower in brown fat and comparable in other organs. In conclusion, lipid accumulation in non-adipose tissues of obese Zucker rats appears to result largely from systemic FA oversupply.
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Quinn LS, Anderson BG, Conner JD, Wolden-Hanson T. IL-15 overexpression promotes endurance, oxidative energy metabolism, and muscle PPARδ, SIRT1, PGC-1α, and PGC-1β expression in male mice. Endocrinology 2013; 154:232-45. [PMID: 23161867 PMCID: PMC3529369 DOI: 10.1210/en.2012-1773] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endurance exercise initiates a pattern of gene expression that promotes fat oxidation, which in turn improves endurance, body composition, and insulin sensitivity. The signals from exercise that initiate these pathways have not been completely characterized. IL-15 is a cytokine that is up-regulated in skeletal muscle after exercise and correlates with leanness and insulin sensitivity. To determine whether IL-15 can induce any of the metabolic adaptations associated with exercise, substrate metabolism, endurance, and molecular expression patterns were examined in male transgenic mice with constitutively elevated muscle and circulating IL-15 levels. IL-15 transgenic mice ran twice as long as littermate control mice in a run-to-exhaustion trial and preferentially used fat for energy metabolism. Fast muscles in IL-15 transgenic mice exhibited high expression of intracellular mediators of oxidative metabolism that are induced by exercise, including sirtuin 1, peroxisome proliferator-activated receptor (PPAR)-δ, PPAR-γ coactivator-1α, and PPAR-γ coactivator-1β. Muscle tissue in IL-15 transgenic mice exhibited myosin heavy chain and troponin I mRNA isoform expression patterns indicative of a more oxidative phenotype than controls. These findings support a role for IL-15 in induction of exercise endurance, oxidative metabolism, and skeletal muscle molecular adaptations induced by physical training.
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Affiliation(s)
- Lebris S Quinn
- S-182 Geriatric Research, Education, and Clinical Center, VA Puget Sound Health Care System, 1660 South Columbian Way, Seattle, WA 98108, USA.
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Moraes ÉA, Natal DIG, Queiroz VAV, Schaffert RE, Cecon PR, de Paula SO, Benjamim LDA, Ribeiro SMR, Martino HSD. Sorghum genotype may reduce low-grade inflammatory response and oxidative stress and maintains jejunum morphology of rats fed a hyperlipidic diet. Food Res Int 2012. [DOI: 10.1016/j.foodres.2012.07.029] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Charles AL, Meyer A, Dal-Ros S, Auger C, Keller N, Ramamoorthy TG, Zoll J, Metzger D, Schini-Kerth V, Geny B. Polyphenols prevent ageing-related impairment in skeletal muscle mitochondrial function through decreased reactive oxygen species production. Exp Physiol 2012; 98:536-45. [DOI: 10.1113/expphysiol.2012.067496] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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45
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Liu Y, Wang C, Wang Y, Ma Z, Xiao J, McClain C, Li X, Feng W. Cobalt chloride decreases fibroblast growth factor-21 expression dependent on oxidative stress but not hypoxia-inducible factor in Caco-2 cells. Toxicol Appl Pharmacol 2012; 264:212-21. [PMID: 22917661 DOI: 10.1016/j.taap.2012.08.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 08/02/2012] [Accepted: 08/03/2012] [Indexed: 01/29/2023]
Abstract
Fibroblast growth factor-21 (FGF21) is a potential metabolic regulator with multiple beneficial effects on metabolic diseases. FGF21 is mainly expressed in the liver, but is also found in other tissues including the intestine, which expresses β-klotho abundantly. The intestine is a unique organ that operates in a physiologically hypoxic environment, and is responsible for the fat absorption processes including triglyceride breakdown, re-synthesis and absorption into the portal circulation. In the present study, we investigated the effects of hypoxia and the chemical hypoxia inducer, cobalt chloride (CoCl(2)), on FGF21 expression in Caco-2 cells and the consequence of fat accumulation. Physical hypoxia (1% oxygen) and CoCl(2) treatment decreased both FGF21 mRNA and secreted protein levels. Gene silence and inhibition of hypoxia-inducible factor-α (HIFα) did not affect the reduction of FGF21 mRNA and protein levels by hypoxia. However, CoCl(2) administration caused a significant increase in oxidative stress. The addition of n-acetylcysteine (NAC) suppressed CoCl(2)-induced reactive oxygen species (ROS) formation and completely negated CoCl(2)-induced FGF21 loss. mRNA stability analysis demonstrated that the CoCl(2) administration caused a remarkable reduction in FGF21 mRNA stability. Furthermore, CoCl(2) increased intracellular triglyceride (TG) accumulation, along with a reduction in mRNA levels of lipid lipase, hormone sensitive lipase (HSL) and adipose triglyceride lipase (ATGL), and an increase of sterol regulatory element-binding protein-1c (SREBP1c) and stearoyl-coenzyme A (SCD1). Addition of both NAC and recombinant FGF21 significantly attenuated the CoCl(2)-induced TG accumulation. In conclusion, the decrease of FGF21 in Caco-2 cells by chemical hypoxia is independent of HIFα, but dependent on an oxidative stress-mediated mechanism. The regulation of FGF21 by hypoxia may contribute to intestinal lipid metabolism and absorption.
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Affiliation(s)
- Yanlong Liu
- School of Pharmacy, Wenzhou Medical College, Wenzhou, China
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46
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Current world literature. Lipid metabolism. Curr Opin Lipidol 2012; 23:248-254. [PMID: 22576583 DOI: 10.1097/mol.0b013e3283543033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Apelin is a peptide known as the ligand of the G-protein-coupled receptor APJ. Several active apelin forms exist such as apelin-36, apelin-17, apelin-13, and the pyroglutamated form of apelin-13. Apelin and APJ are expressed in the central nervous system, particularly in the hypothalamus and in many peripheral tissues. Apelin has been shown to be involved in the regulation of cardiovascular and fluid homeostasis, food intake, cell proliferation, and angiogenesis. In addition to be an ubiquitous peptide, apelin is also produced and secreted by adipocytes and thus considered as an adipokine. This has opened a new field of investigation establishing a link between apelin and metabolic disorders (obesity, type 2 diabetes, etc.) which is the focus of the present review. Several studies, but not all, have reported an increase of plasma apelin concentrations in humans and in animal models with different metabolic pathologies. Moreover, important roles for apelin both in glucose and lipid metabolism have been highlighted as well as the associated signaling pathways. Apelin appears as a beneficial adipokine with anti-obesity and anti-diabetic properties and thus as a promising therapeutic target in metabolic disorders.
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Affiliation(s)
- Isabelle Castan-Laurell
- UMR 1048 INSERM, Institut des Maladies Métaboliques et Cardiovasculaires (I2MC)/Université Paul Sabatier, 1 Ave J. Poulhès, BP 84225, 31432, Toulouse Cedex 4, France.
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Handschin C. Peroxisome proliferator-activated receptor γ coactivator 1β (PGC-1β) improves skeletal muscle mitochondrial function and insulin sensitivity. Diabetologia 2011; 54:1270-2. [PMID: 21461634 DOI: 10.1007/s00125-011-2135-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 03/10/2011] [Indexed: 10/18/2022]
Abstract
Proteins belonging to the peroxisome proliferator-activated receptor γ coactivator 1 (PGC-1) family are key regulators of cellular energy homeostasis in a number of oxidative tissues, including skeletal muscle. While the regulation and function of PGC-1α seems central to muscle fibre plasticity in endurance exercise, the role of PGC-1β in this tissue is less clear. Wright et al. (Diabetologia, DOI: 10.1007/s00125-011-2068-x ) provide evidence for a protective effect of moderately elevated PGC-1β in electroporated rat skeletal muscle against high-fat-diet-induced insulin resistance, at least in part by promoting the oxidation of long chain acyl-CoA entities and the elimination of reactive oxygen species. These data provide important insights into the biological role of PGC-1β in skeletal muscle and imply novel therapeutic avenues for improving peripheral insulin sensitivity.
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Affiliation(s)
- C Handschin
- Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland.
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Mendelsohn A, Larrick JW. Master switch of mitochondrial biogenesis: a clinical target for health span enhancement? Rejuvenation Res 2011; 14:223-6. [PMID: 21595503 DOI: 10.1089/rej.2011.1194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Andrew Mendelsohn
- Panorama Research Institute and Regenerative Sciences Institute, Sunnyvale, California 94089, USA.
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