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Association between single nucleotide polymorphisms within genes encoding sirtuin families and diabetic nephropathy in Japanese subjects with type 2 diabetes. Clin Exp Nephrol 2011; 15:381-390. [PMID: 21331741 PMCID: PMC3110272 DOI: 10.1007/s10157-011-0418-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 01/19/2011] [Indexed: 11/21/2022]
Abstract
Background Sirtuin is a member of the nicotinamide adenine dinucleotide (NAD)-dependent deacetylases, and has been reported to play a pivotal role in energy expenditure, mitochondrial function and pathogenesis of metabolic diseases, including aging kidneys. In this study, we focused on the genes encoding sirtuin families, and examined the association between single nucleotide polymorphisms (SNPs) within genes encoding sirtuin families and diabetic nephropathy. Methods We examined 52 SNPs within the SIRT genes (11 in SIRT1, 7 in SIRT2, 14 in SIRT3, 7 in SIRT4, 9 in SIRT5, and 4 in SIRT6) in 3 independent Japanese populations with type 2 diabetes (study 1: 747 cases (overt proteinuria), 557 controls; study 2: 455 cases (overt proteinuria) and 965 controls; study 3: 300 cases (end-stage renal disease) and 218 controls). The associations between these SNPs were analyzed by the Cochran–Armitage trend test, and results of the 3 studies were combined with a meta-analysis. We further examined an independent cohort (195 proteinuria cases and 264 controls) for validation of the original association. Results We identified 4 SNPs in SIRT1 that were nominally associated with diabetic nephropathy (P < 0.05), and subsequent haplotype analysis revealed that a haplotype consisting of the 11 SNPs within SIRT1 locus had a stronger association (P = 0.0028). Conclusion These results indicate that SIRT1 may play a role in susceptibility to diabetic nephropathy in Japanese subjects with type 2 diabetes. Electronic supplementary material The online version of this article (doi:10.1007/s10157-011-0418-0) contains supplementary material, which is available to authorized users.
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252
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Kitada M, Kume S, Imaizumi N, Koya D. Resveratrol improves oxidative stress and protects against diabetic nephropathy through normalization of Mn-SOD dysfunction in AMPK/SIRT1-independent pathway. Diabetes 2011; 60:634-43. [PMID: 21270273 PMCID: PMC3028365 DOI: 10.2337/db10-0386] [Citation(s) in RCA: 271] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE Despite the beneficial effects of resveratrol (RSV) on cardiovascular disease and life span, its effects on type 2 diabetic nephropathy remain unknown. This study examined the renoprotective effects of RSV in db/db mice, a model of type 2 diabetes. RESEARCH DESIGN AND METHODS db/db mice were treated with RSV (0.3% mixed in chow) for 8 weeks. We measured urinary albumin excretion (UAE), histological changes (including mesangial expansion, fibronectin accumulation, and macrophage infiltration), oxidative stress markers (urinary excretion and mitochondrial content of 8-hydroxy-2'-deoxyguanosine [8-OHdG], nitrotyrosine expression), and manganese-superoxide dismutase (Mn-SOD) activity together with its tyrosine-nitrated modification and mitochondrial biogenesis in the kidney. Blood glucose, glycated hemoglobin, and plasma lipid profiles were also measured. The phosphorylation of 5'-AMP-activated kinase (AMPK) and expression of silent information regulator 1 (SIRT1) in the kidney were assessed by immunoblotting. RESULTS RSV significantly reduced UAE and attenuated renal pathological changes in db/db mice. Mitochondrial oxidative stress and biogenesis were enhanced in db/db mice; however, Mn-SOD activity was reduced through increased tyrosine-nitrated modification. RSV ameliorated such alterations and partially improved blood glucose, glycated hemoglobin, and abnormal lipid profile in db/db mice. Activation of AMPK was decreased in the kidney of db/db mice compared with db/m mice. RSV neither modified AMPK activation nor SIRT1 expression in the kidney. CONCLUSIONS RSV ameliorates renal injury and enhanced mitochondrial biogenesis with Mn-SOD dysfunction in the kidney of db/db mice, through improvement of oxidative stress via normalization of Mn-SOD function and glucose-lipid metabolism. RSV has antioxidative activities via AMPK/SIRT1-independent pathway.
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Affiliation(s)
- Munehiro Kitada
- Division of Diabetes and Endocrinology, Kanazawa Medical University, Kahoku-Gun, Ishikawa, Japan
| | - Shinji Kume
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Noriko Imaizumi
- Division of Diabetes and Endocrinology, Kanazawa Medical University, Kahoku-Gun, Ishikawa, Japan
| | - Daisuke Koya
- Division of Diabetes and Endocrinology, Kanazawa Medical University, Kahoku-Gun, Ishikawa, Japan
- Corresponding author: Daisuke Koya,
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253
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Abstract
Exercise, together with a low-energy diet, is the first-line treatment for type 2 diabetes type 2 diabetes . Exercise improves insulin sensitivity insulin sensitivity by increasing the number or function of muscle mitochondria mitochondria and the capacity for aerobic metabolism, all of which are low in many insulin-resistant subjects. Cannabinoid 1-receptor antagonists and β-adrenoceptor agonists improve insulin sensitivity in humans and promote fat oxidation in rodents independently of reduced food intake. Current drugs for the treatment of diabetes are not, however, noted for their ability to increase fat oxidation, although the thiazolidinediones increase the capacity for fat oxidation in skeletal muscle, whilst paradoxically increasing weight gain.There are a number of targets for anti-diabetic drugs that may improve insulin sensitivity insulin sensitivity by increasing the capacity for fat oxidation. Their mechanisms of action are linked, notably through AMP-activated protein kinase, adiponectin, and the sympathetic nervous system. If ligands for these targets have obvious acute thermogenic activity, it is often because they increase sympathetic activity. This promotes fuel mobilisation, as well as fuel oxidation. When thermogenesis thermogenesis is not obvious, researchers often argue that it has occurred by using the inappropriate device of treating animals for days or weeks until there is weight (mainly fat) loss and then expressing energy expenditure energy expenditure relative to body weight. In reality, thermogenesis may have occurred, but it is too small to detect, and this device distracts us from really appreciating why insulin sensitivity has improved. This is that by increasing fatty acid oxidation fatty acid oxidation more than fatty acid supply, drugs lower the concentrations of fatty acid metabolites that cause insulin resistance. Insulin sensitivity improves long before any anti-obesity effect can be detected.
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Affiliation(s)
- Jonathan R S Arch
- Clore Laboratory, University of Buckingham, Buckingham, MK18 1EG, UK
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254
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The role of class I histone deacetylase (HDAC) on gluconeogenesis in liver. Biochem Biophys Res Commun 2010; 404:166-72. [PMID: 21108932 DOI: 10.1016/j.bbrc.2010.11.086] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2010] [Accepted: 11/18/2010] [Indexed: 11/22/2022]
Abstract
Hepatic gluconeogenesis is crucial for glucose homeostasis. Although sirtuin 1 (Sirt1) is implicated in the regulation of gluconeogenesis in the liver, the effects of other histone deacetylases (HDAC) on gluconeogenesis are unclear. The aim of this study was to identify the role of class I HDACs in hepatic gluconeogenesis. In HepG2 cells and the liver of mice, the expressions of phosphoenol pyruvate carboxykinase (PEPCK) and hepatocyte nuclear factor 4α (HNF4α) were significantly decreased by treatment with a newly designed class I HDAC inhibitor, Ky-2. SiRNA knockdown of HDAC1 expression, but not of HDAC2 or HDAC3, in HepG2 cells decreased PEPCK and HNF4α expression. In HepG2 cells, insulin-stimulated phosphorylation of Akt and forkhead box O 1 (FoxO1) was increased by Ky-2. Pyruvate tolerance tests in Ky-2-treated high-fat-diet (HFD)-fed mice showed a marked reduction in blood glucose compared with vehicle-treated HFD mice. These data suggest that class I HDACs increase HNF4α protein expression and the transcriptional activity of FoxO1, followed by the induction of PEPCK mRNA expression and gluconeogenesis in liver.
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255
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Maki RG. Small is beautiful: insulin-like growth factors and their role in growth, development, and cancer. J Clin Oncol 2010; 28:4985-95. [PMID: 20975071 PMCID: PMC3039924 DOI: 10.1200/jco.2009.27.5040] [Citation(s) in RCA: 164] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 08/23/2010] [Indexed: 12/17/2022] Open
Abstract
Insulin-like growth factors were discovered more than 50 years ago as mediators of growth hormone that effect growth and differentiation of bone and skeletal muscle. Interest of the role of insulin-like growth factors in cancer reached a peak in the 1990s, and then waned until the availability in the past 5 years of monoclonal antibodies and small molecules that block the insulin-like growth factor 1 receptor. In this article, we review the history of insulin-like growth factors and their role in growth, development, organism survival, and in cancer, both epithelial cancers and sarcomas. Recent developments regarding phase I to II clinical trials of such agents are discussed, as well as potential studies to consider in the future, given the lack of efficacy of one such monoclonal antibody in combination with cytotoxic chemotherapy in a first-line study in metastatic non-small-cell lung adenocarcinoma. Greater success with these agents clinically is expected when combining the agents with inhibitors of other cell signaling pathways in which cross-resistance has been observed.
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Affiliation(s)
- Robert G Maki
- Memorial Sloan-Kettering Cancer Center, New York, NY 10065-6007, USA.
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256
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Low-Frequency Electroacupuncture Improves Insulin Sensitivity in Obese Diabetic Mice through Activation of SIRT1/PGC-1α in Skeletal Muscle. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2010; 2011:735297. [PMID: 20981161 PMCID: PMC2964507 DOI: 10.1155/2011/735297] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 09/23/2010] [Indexed: 11/23/2022]
Abstract
Electroacupuncture (EA) has been observed to reduce insulin resistance in obesity and diabetes. However, the biochemical mechanism underlying this effect remains unclear. This study investigated the effects of low-frequency EA on metabolic action in genetically obese and type 2 diabetic db/db mice. Nine-week-old db/m and db/db mice were randomly divided into four groups, namely, db/m, db/m + EA, db/db, and db/db + EA. db/m + EA and db/db + EA mice received 3-Hz electroacupuncture five times weekly for eight consecutive weeks. In db/db mice, EA tempered the increase in fasting blood glucose, food intake, and body mass and maintained insulin levels. In EA-treated db/db mice, improved insulin sensitivity was established through intraperitoneal insulin tolerance test. EA was likewise observed to decrease free fatty acid levels in db/db mice; it increased protein expression in skeletal muscle Sirtuin 1 (SIRT1) and induced gene expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), nuclear respiratory factor 1 (NRF1), and acyl-CoA oxidase (ACOX). These results indicated that EA offers a beneficial effect on insulin resistance in obese and diabetic db/db mice, at least partly, via stimulation of SIRT1/PGC-1α, thus resulting in improved insulin signal.
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257
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Abstract
Genetic screens in Drosophila have been instrumental in distinguishing approximately 390 loci involved in position effect variegation and heterochromatin stabilization. Most of the identified genes [so-called Su(var) and E(var) genes] are also conserved in mammals, where more than 50 of their gene products are known to localize to constitutive heterochromatin. From these proteins, approximately 12 core heterochromatin components can be inferred. In addition, there are approximately 30 additional Su(var) and 10 E(var) factors that can, under distinct developmental options, interchange with constitutive heterochromatin and participate in the partitioning of the genome into repressed and active chromatin domains. A significant fraction of the Su(var) and E(var) factors are enzymes that respond to environmental and metabolic signals, thereby allowing both the variation and propagation of epigenetic states to a dynamic chromatin template. Moreover, the misregulation of human SU(VAR) and E(VAR) function can advance cancer and many other human diseases including more complex disorders. As such, mammalian Su(var) and E(var) genes and their products provide a rich source of novel targets for diagnosis of and pharmaceutical intervention in many human diseases.
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Affiliation(s)
- Barna D Fodor
- Max-Planck Institute of Immunobiology, D-79108 Freiburg, Germany.
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258
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Shan T, Ren Y, Liu Y, Zhu L, Wang Y. Breed difference and regulation of the porcine Sirtuin 1 by insulin. J Anim Sci 2010; 88:3909-17. [PMID: 20802141 DOI: 10.2527/jas.2010-2880] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Sirtuin 1 (Sirt1) plays an important role in fat metabolism. In the current study, we examined the breed differences in Sirt1 between Jinhua pigs (a fatty breed of China) and Landrace pigs (a leaner breed). In addition, the effect of insulin on the gene expression of Sirt1 and the major lipase, adipose triglyceride lipase (ATGL), and hormone-sensitive lipase (HSL) in fat metabolism was also studied in vitro. Compared with the Landrace pigs, the BW of Jinhua pigs was less (P < 0.01), whereas the body fat content were greater (P < 0.01). The protein content and the mRNA abundance of Sirt1 in Jinhua pigs were less (P < 0.01) in subcutaneous adipose tissues compared with the Landrace pigs. Likewise, the mRNA abundance of ATGL and HSL were also less (P < 0.01) in Jinhua pigs. In vitro, treatment with a different dose of insulin (10, 50 and 100 nM) decreased (P < 0.01) glycerol release and the mRNA abundance of Sirt1, ATGL, and HSL in porcine adipocytes. Likewise, treatment with 50 nM insulin for 24 and 48 h also decreased (P < 0.05) glycerol release and the expression of Sirt1, ATGL, and HSL in porcine adipocytes. Furthermore, insulin and Sirt1-specific small interfering RNA treatment decreased (P < 0.01) the expression of Sirt1, ATGL, and HSL compared with the control or insulin treatment. These results indicate that insulin may regulate transcription of Sirt1, ATGL, and HSL in porcine adipocytes and provide information for manipulating these gene expressions in regulating fat metabolism in pigs.
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Affiliation(s)
- T Shan
- Institute of Feed Science, Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Key Laboratory of Feed and Animal Nutrition of Zhejiang Province, Zhejiang University, Hangzhou 310029, PR China
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259
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Segrè AV, Groop L, Mootha VK, Daly MJ, Altshuler D. Common inherited variation in mitochondrial genes is not enriched for associations with type 2 diabetes or related glycemic traits. PLoS Genet 2010; 6. [PMID: 20714348 PMCID: PMC2920848 DOI: 10.1371/journal.pgen.1001058] [Citation(s) in RCA: 395] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 07/08/2010] [Indexed: 01/02/2023] Open
Abstract
Mitochondrial dysfunction has been observed in skeletal muscle of people with diabetes and insulin-resistant individuals. Furthermore, inherited mutations in mitochondrial DNA can cause a rare form of diabetes. However, it is unclear whether mitochondrial dysfunction is a primary cause of the common form of diabetes. To date, common genetic variants robustly associated with type 2 diabetes (T2D) are not known to affect mitochondrial function. One possibility is that multiple mitochondrial genes contain modest genetic effects that collectively influence T2D risk. To test this hypothesis we developed a method named Meta-Analysis Gene-set Enrichment of variaNT Associations (MAGENTA; http://www.broadinstitute.org/mpg/magenta). MAGENTA, in analogy to Gene Set Enrichment Analysis, tests whether sets of functionally related genes are enriched for associations with a polygenic disease or trait. MAGENTA was specifically designed to exploit the statistical power of large genome-wide association (GWA) study meta-analyses whose individual genotypes are not available. This is achieved by combining variant association p-values into gene scores and then correcting for confounders, such as gene size, variant number, and linkage disequilibrium properties. Using simulations, we determined the range of parameters for which MAGENTA can detect associations likely missed by single-marker analysis. We verified MAGENTA's performance on empirical data by identifying known relevant pathways in lipid and lipoprotein GWA meta-analyses. We then tested our mitochondrial hypothesis by applying MAGENTA to three gene sets: nuclear regulators of mitochondrial genes, oxidative phosphorylation genes, and ∼1,000 nuclear-encoded mitochondrial genes. The analysis was performed using the most recent T2D GWA meta-analysis of 47,117 people and meta-analyses of seven diabetes-related glycemic traits (up to 46,186 non-diabetic individuals). This well-powered analysis found no significant enrichment of associations to T2D or any of the glycemic traits in any of the gene sets tested. These results suggest that common variants affecting nuclear-encoded mitochondrial genes have at most a small genetic contribution to T2D susceptibility. Mitochondria play a crucial role in metabolic homeostasis, and alteration of mitochondrial function is a hallmark of diabetes. While mitochondrial activity is reduced in people with diabetes, it is unclear whether mitochondrial dysfunction is a cause or effect of type 2 diabetes. Genome-wide association studies for type 2 diabetes have explained ≈10% of the heritability of the disease, but none of the loci are known to affect mitochondrial activity. It is possible though that a mitochondrial contribution is hidden in the remaining 90%. Hence, we tested the hypothesis that multiple mitochondria-related genes encoded in the nucleus, each having a weak effect (hard to detect individually), can collectively influence type 2 diabetes. To address this, we developed a computational method (MAGENTA) that allowed us to adequately analyze large collective datasets of human genetic variation obtained from collaborative studies of type 2 diabetes and related glycemic traits. Despite the increased sensitivity of MAGENTA compared to single-DNA variant analysis, we found no support for a causal relationship between mitochondrial dysfunction and type 2 diabetes. These results may help steer future efforts in understanding the pathogenesis of the disease. MAGENTA is broadly applicable to testing associations between other biological pathways and common diseases or traits.
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Affiliation(s)
- Ayellet V. Segrè
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- * E-mail: (DA); (AVS)
| | | | | | - Leif Groop
- Department of Clinical Sciences, Diabetes and Endocrinology Research Unit, University Hospital Malmö, Lund University, Malmö, Sweden
| | - Vamsi K. Mootha
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Mark J. Daly
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - David Altshuler
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
- Diabetes Unit, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (DA); (AVS)
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260
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Chen YR, Fang SR, Fu YC, Zhou XH, Xu MY, Xu WC. Calorie restriction on insulin resistance and expression of SIRT1 and SIRT4 in rats. Biochem Cell Biol 2010; 88:715-22. [PMID: 20651844 DOI: 10.1139/o10-010] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The sirtuin proteins are nicotinamide adenine dinucleotide dependent deacetylases and adenosine diphosphate (ADP)-ribosyl transferases associated with metabolic balance and lifespan extension. Sirtuin 1 (SIRT1) and sirtuin 4 (SIRT4) have been reported to regulate insulin secretion, but their association with the development of insulin resistance and nonalcoholic fatty liver disease remain undefined. The aim of this study was to determine the expression of SIRT1 and SIRT4 in the liver and pancreas of rats fed with different diets and analyze the association of these proteins with insulin resistance and nonalcoholic fatty liver disease. Male Sprague-Dawley rats were randomly divided into the following 4 diet treatment groups: normal control (NC), calorie restriction (CR), high-fat (HFa), and high-fructose (HFr), and these groups were maintained for 12 weeks. Blood biochemical analysis and histopathology indicated that HFa and HFr groups were insulin resistant and developed nonalcoholic fatty livers. SIRT1 was present in the nucleus and cytoplasm of the pancreatic beta-cells, while SIRT4 was located in the cytoplasm. Treatment with the CR diet increased the expression of SIRT1 in both the pancreas and liver, while treatment with the HFa and HFr diets caused a decrease. SIRT4 was upregulated in the liver of rats treated with the HFa diet, but did not change with the CR diet treatment. These data suggest that SIRT1 and SIRT4 were both involved in the development of insulin resistance and nonalcoholic fatty liver disease.
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Affiliation(s)
- Yong-Ru Chen
- Department of Endocrinology, The First Affiliated Hospital of Shantou University Medical College, Shantou, China
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261
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Villeneuve LM, Natarajan R. The role of epigenetics in the pathology of diabetic complications. Am J Physiol Renal Physiol 2010; 299:F14-25. [PMID: 20462972 DOI: 10.1152/ajprenal.00200.2010] [Citation(s) in RCA: 227] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Diabetes is associated with significantly accelerated rates of several debilitating microvascular complications such as nephropathy, retinopathy, and neuropathy, and macrovascular complications such as atherosclerosis and stroke. While several studies have been devoted to the evaluation of genetic factors related to type 1 and type 2 diabetes and associated complications, much less is known about epigenetic changes that occur without alterations in the DNA sequence. Environmental factors and nutrition have been implicated in diabetes and can also affect epigenetic states. Exciting research has shown that epigenetic changes in chromatin can affect gene transcription in response to environmental stimuli, and changes in key chromatin histone methylation patterns have been noted under diabetic conditions. Reports also suggest that epigenetics may be involved in the phenomenon of metabolic memory observed in clinic trials and animal studies. Further exploration into epigenetic mechanisms can yield new insights into the pathogenesis of diabetes and its complications and uncover potential therapeutic targets and treatment options to prevent the continued development of diabetic complications even after glucose control has been achieved.
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Affiliation(s)
- Louisa M Villeneuve
- Department of Diabetes, Beckman Research Institute of City of Hope, Duarte, California 91010, USA
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262
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Cruz M, Valladares-Salgado A, Garcia-Mena J, Ross K, Edwards M, Angeles-Martinez J, Ortega-Camarillo C, de la Peña JE, Burguete-Garcia AI, Wacher-Rodarte N, Ambriz R, Rivera R, D'artote AL, Peralta J, Parra EJ, Kumate J. Candidate gene association study conditioning on individual ancestry in patients with type 2 diabetes and metabolic syndrome from Mexico City. Diabetes Metab Res Rev 2010; 26:261-70. [PMID: 20503258 DOI: 10.1002/dmrr.1082] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Type 2 diabetes (T2D) is influenced by diverse environmental and genetic risk factors. Metabolic syndrome (MS) increases the risk of cardiovascular disease and diabetes. We analysed 14 cases of polymorphisms located in 10 candidate loci, in a sample of patients with T2D and controls from Mexico City. METHODS We analysed the association of 14 polymorphisms located within 10 genes (TCF7L2, ENPP1, ADRB3, KCNJ11, LEPR, PPARgamma, FTO, CDKAL1, SIRT1 and HHEX) with T2D and MS. The analysis included 519 subjects with T2D defined according to the ADA criteria, 389 with MS defined according to the AHA/NHLBI criteria and 547 controls. Association was tested with the program ADMIXMAP including individual ancestry, age, sex, education and in some cases body mass index (BMI), in a logistic regression model. RESULTS The two markers located within the TCF7L2 gene showed strong associations with T2D (rs7903146, T allele, odd ratio (OR) = 1.76, p = 0.001 and rs12255372, T allele, OR = 1.78, p = 0.002), but did not show significant association with MS. The non-synonymous rs4994 polymorphism of the ADRB3 gene was associated with T2D (Trp allele, OR = 0.62, p = 0.001) and MS (Trp allele, OR = 0.74, p = 0.018). Nominally significant associations were also observed between T2D and the SIRT1 rs3758391 SNP and MS and the HHEX rs5015480 polymorphism. CONCLUSIONS Variants located within the gene TCF7L2 are strongly associated with T2D but not with MS, providing support to previous evidence indicating that polymorphisms at the TCF7L2 gene increase T2D risk. In contrast, the non-synonymous ADRB3 rs4994 polymorphism is associated with T2D and MS.
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Affiliation(s)
- M Cruz
- Unidad de Investigacion Medica en Bioquimica, Hospital de Especialidades, Instituto Mexicano del Seguro Social, CMN Siglo XXI, Mexico, DF, Mexico.
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263
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Ruderman NB, Xu XJ, Nelson L, Cacicedo JM, Saha AK, Lan F, Ido Y. AMPK and SIRT1: a long-standing partnership? Am J Physiol Endocrinol Metab 2010; 298:E751-60. [PMID: 20103737 PMCID: PMC2853213 DOI: 10.1152/ajpendo.00745.2009] [Citation(s) in RCA: 661] [Impact Index Per Article: 47.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
AMP-activated protein kinase (AMPK) and the histone/protein deacetylase SIRT1 are fuel-sensing molecules that have coexisted in cells throughout evolution. When a cell's energy state is diminished, AMPK activation restores energy balance by stimulating catabolic processes that generate ATP and downregulating anabolic processes that consume ATP but are not acutely needed for survival. SIRT1 in turn is best known historically for producing genetic changes that mediate the increase in longevity caused by calorie restriction. Although the two molecules have been studied intensively for many years, only recently has it become apparent that they have similar effects on diverse processes such as cellular fuel metabolism, inflammation, and mitochondrial function. In this review we will examine the evidence that these similarities occur because AMPK and SIRT1 both regulate each other and share many common target molecules. In addition, we will discuss the clinical relevance of these interactions and in particular the possibility that their dysregulation predisposes to disorders such as type 2 diabetes and atherosclerotic cardiovascular disease and is a target for their therapy.
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Affiliation(s)
- Neil B Ruderman
- Departments of Medicine, Physiology, and Biophysics, Boston University School of Medicine and Boston Medical Center, Boston, Massachusetts 02118, USA.
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264
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Pacholec M, Bleasdale JE, Chrunyk B, Cunningham D, Flynn D, Garofalo RS, Griffith D, Griffor M, Loulakis P, Pabst B, Qiu X, Stockman B, Thanabal V, Varghese A, Ward J, Withka J, Ahn K. SRT1720, SRT2183, SRT1460, and resveratrol are not direct activators of SIRT1. J Biol Chem 2010; 285:8340-51. [PMID: 20061378 PMCID: PMC2832984 DOI: 10.1074/jbc.m109.088682] [Citation(s) in RCA: 700] [Impact Index Per Article: 50.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Revised: 01/07/2010] [Indexed: 01/22/2023] Open
Abstract
Sirtuins catalyze NAD(+)-dependent protein deacetylation and are critical regulators of transcription, apoptosis, metabolism, and aging. There are seven human sirtuins (SIRT1-7), and SIRT1 has been implicated as a key mediator of the pathways downstream of calorie restriction that have been shown to delay the onset and reduce the incidence of age-related diseases such as type 2 diabetes. Increasing SIRT1 activity, either by transgenic overexpression of the Sirt1 gene in mice or by pharmacological activation by small molecule activators resveratrol and SRT1720, has shown beneficial effects in rodent models of type 2 diabetes, indicating that SIRT1 may represent an attractive therapeutic target. Herein, we have assessed purported SIRT1 activators by employing biochemical assays utilizing native substrates, including a p53-derived peptide substrate lacking a fluorophore as well as the purified native full-length protein substrates p53 and acetyl-CoA synthetase1. SRT1720, its structurally related compounds SRT2183 and SRT1460, and resveratrol do not lead to apparent activation of SIRT1 with native peptide or full-length protein substrates, whereas they do activate SIRT1 with peptide substrate containing a covalently attached fluorophore. Employing NMR, surface plasmon resonance, and isothermal calorimetry techniques, we provide evidence that these compounds directly interact with fluorophore-containing peptide substrates. Furthermore, we demonstrate that SRT1720 neither lowers plasma glucose nor improves mitochondrial capacity in mice fed a high fat diet. SRT1720, SRT2183, SRT1460, and resveratrol exhibit multiple off-target activities against receptors, enzymes, transporters, and ion channels. Taken together, we conclude that SRT1720, SRT2183, SRT1460, and resveratrol are not direct activators of SIRT1.
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Affiliation(s)
- Michelle Pacholec
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - John E. Bleasdale
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - Boris Chrunyk
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - David Cunningham
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Declan Flynn
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - Robert S. Garofalo
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - David Griffith
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - Matt Griffor
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Pat Loulakis
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Brandon Pabst
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - Xiayang Qiu
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Brian Stockman
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Venkataraman Thanabal
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Alison Varghese
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Jessica Ward
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
| | - Jane Withka
- Structural Biology, Pfizer Global Research and Development, Groton, Connecticut 06340
| | - Kay Ahn
- From the Departments of Cardiovascular, Metabolic and Endocrine Diseases and
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Abstract
The incidence of the metabolic syndrome represents a spectrum of disorders that continue to increase across the industrialized world. Both genetic and environmental factors contribute to metabolic syndrome and recent evidence has emerged to suggest that alterations in circadian systems and sleep participate in the pathogenesis of the disease. In this review, we highlight studies at the intersection of clinical medicine and experimental genetics that pinpoint how perturbations of the internal clock system, and sleep, constitute risk factors for disorders including obesity, diabetes mellitus, cardiovascular disease, thrombosis and even inflammation. An exciting aspect of the field has been the integration of behavioral and physiological approaches, and the emerging insight into both neural and peripheral tissues in disease pathogenesis. Consideration of the cell and molecular links between disorders of circadian rhythms and sleep with metabolic syndrome has begun to open new opportunities for mechanism-based therapeutics.
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Affiliation(s)
- Eleonore Maury
- Department of Medicine, Division of Endocrinology, Metabolism, and Molecular Medicine, Northwestern University Feinberg School of Medicine, 2200 Campus Drive, Evanston, Illinois 60208
- Department of Neurobiology and Physiology, Northwestern University, 2200 Campus Drive, Evanston, Illinois 60208
| | - Kathryn Moynihan Ramsey
- Department of Medicine, Division of Endocrinology, Metabolism, and Molecular Medicine, Northwestern University Feinberg School of Medicine, 2200 Campus Drive, Evanston, Illinois 60208
- Department of Neurobiology and Physiology, Northwestern University, 2200 Campus Drive, Evanston, Illinois 60208
| | - Joseph Bass
- Department of Medicine, Division of Endocrinology, Metabolism, and Molecular Medicine, Northwestern University Feinberg School of Medicine, 2200 Campus Drive, Evanston, Illinois 60208
- Department of Neurobiology and Physiology, Northwestern University, 2200 Campus Drive, Evanston, Illinois 60208
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266
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Simonis-Bik AM, Nijpels G, van Haeften TW, Houwing-Duistermaat JJ, Boomsma DI, Reiling E, van Hove EC, Diamant M, Kramer MH, Heine RJ, Maassen JA, Slagboom PE, Willemsen G, Dekker JM, Eekhoff EM, de Geus EJ, 't Hart LM. Gene variants in the novel type 2 diabetes loci CDC123/CAMK1D, THADA, ADAMTS9, BCL11A, and MTNR1B affect different aspects of pancreatic beta-cell function. Diabetes 2010; 59:293-301. [PMID: 19833888 PMCID: PMC2797936 DOI: 10.2337/db09-1048] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Recently, results from a meta-analysis of genome-wide association studies have yielded a number of novel type 2 diabetes loci. However, conflicting results have been published regarding their effects on insulin secretion and insulin sensitivity. In this study we used hyperglycemic clamps with three different stimuli to test associations between these novel loci and various measures of beta-cell function. RESEARCH DESIGN AND METHODS For this study, 336 participants, 180 normal glucose tolerant and 156 impaired glucose tolerant, underwent a 2-h hyperglycemic clamp. In a subset we also assessed the response to glucagon-like peptide (GLP)-1 and arginine during an extended clamp (n = 123). All subjects were genotyped for gene variants in JAZF1, CDC123/CAMK1D, TSPAN8/LGR5, THADA, ADAMTS9, NOTCH2/ADAMS30, DCD, VEGFA, BCL11A, HNF1B, WFS1, and MTNR1B. RESULTS Gene variants in CDC123/CAMK1D, ADAMTS9, BCL11A, and MTNR1B affected various aspects of the insulin response to glucose (all P < 6.9 x 10(-3)). The THADA gene variant was associated with lower beta-cell response to GLP-1 and arginine (both P < 1.6 x 10(-3)), suggesting lower beta-cell mass as a possible pathogenic mechanism. Remarkably, we also noted a trend toward an increased insulin response to GLP-1 in carriers of MTNR1B (P = 0.03), which may offer new therapeutic possibilities. The other seven loci were not detectably associated with beta-cell function. CONCLUSIONS Diabetes risk alleles in CDC123/CAMK1D, THADA, ADAMTS9, BCL11A, and MTNR1B are associated with various specific aspects of beta-cell function. These findings point to a clear diversity in the impact that these various gene variants may have on (dys)function of pancreatic beta-cells.
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Affiliation(s)
| | - Giel Nijpels
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | - Timon W. van Haeften
- Department of Internal Medicine, Utrecht University Medical Center, Utrecht, the Netherlands
| | | | - Dorret I. Boomsma
- Department of Biological Psychology, VU University, Amsterdam, the Netherlands
| | - Erwin Reiling
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Els C. van Hove
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Michaela Diamant
- Diabetes Center, VU University Medical Center, Amsterdam, the Netherlands
| | - Mark H.H. Kramer
- Diabetes Center, VU University Medical Center, Amsterdam, the Netherlands
| | - Robert J. Heine
- Diabetes Center, VU University Medical Center, Amsterdam, the Netherlands
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
- Eli Lilly & Company, Indianapolis, Indiana
| | - J. Antonie Maassen
- Diabetes Center, VU University Medical Center, Amsterdam, the Netherlands
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - P. Eline Slagboom
- Department of Medical Statistics, Leiden University Medical Center, Leiden, the Netherlands
| | - Gonneke Willemsen
- Department of Biological Psychology, VU University, Amsterdam, the Netherlands
| | - Jacqueline M. Dekker
- EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, the Netherlands
| | | | - Eco J. de Geus
- Department of Biological Psychology, VU University, Amsterdam, the Netherlands
| | - Leen M. 't Hart
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
- Corresponding author: Leen M. 't Hart,
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267
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Abstract
Adiponectin is an adipose-tissue-derived hormone with anti-diabetic, anti-atherogenic and anti-inflammatory functions. Adiponectin circulates in the bloodstream in trimeric, hexameric and high-molecular-mass species, and different forms of adiponectin have been found to play distinct roles in the regulation of energy homoeostasis. The serum levels of adiponectin are negatively correlated with obesity and insulin resistance, yet the underlying mechanisms remain elusive. In the present review, we summarize recent progress made on the mechanisms regulating adiponectin gene transcription, multimerization and secretion. We also discuss the potential relevance of these studies to the development of new clinical therapy for insulin resistance, Type 2 diabetes and other obesity-related metabolic disorders.
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268
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Abstract
Experimental, epidemiological and clinical evidence implicates insulin resistance and its accompanying hyperinsulinaemia in the development of cancer, but the relative importance of these disturbances in cancer remains unclear. There are, however, theoretical mechanisms by which hyperinsulinaemia could amplify such growth-promoting effects as insulin may have, as well as the growth-promoting effects of other, more potent, growth factors. Hyperinsulinaemia may also induce other changes, particularly in the IGF (insulin-like growth factor) system, that could promote cell proliferation and survival. Several factors can independently modify both cancer risk and insulin resistance, including subclinical inflammation and obesity. The possibility that some of the effects of hyperinsulinaemia might then augment pro-carcinogenic changes associated with disturbances in these factors emphasizes how, rather than being a single causative factor, insulin resistance may be most usefully viewed as one strand in a network of interacting disturbances that promote the development and progression of cancer.
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