calpain and Diabetes-Mellitus--Type-2

A correlation between the single nucleotide polymorphism (SNP)43 G>A in the calpain-10 (CAPN10) gene (i.e., CAPN10 SNP43) and type 2 diabetes mellitus (T2DM) susceptibility has been suggested, but the evidence for such a relationship remains controversial. To explore the association of the CAPN10 SNP43 with T2DM in Asian populations, a meta-analysis including 9,353 participants from 20 individual studies in Asian populations was conducted. The pooled odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were evaluated by a fixed-effect model or random-effect model. The relationship between CAPN10 SNP43 and T2DM was significant under allelic (OR: 1.18, 95% CI: 1.01-1.38, P = 0.03), recessive (OR: 1.236, 95% CI: 1.038-1.472, P =0.017), heterozygous (OR: 1.261, 95% CI: 1.053-1.512, P = 0.012), and additive (OR: 1.183, 95% CI: 1.014-1.381, P = 0.033) genetic models but not under dominant (OR: 1.12, 95% CI: 0.78-1.62, P = 0.53) or homozygous (OR: 0.937, 95% CI: 0.648-1.355, P = 0.730) genetic models. CAPN10 SNP43 was significantly associated with T2DM susceptibility in Asian populations, especially in Chinese populations. Asians, particularly Chinese people with the SNP43 G allele of the CAPN10 gene may have an increased risk of developing T2DM.

Topics: Alleles; Asian People; Calpain; China; Diabetes Mellitus, Type 2; Genetic Association Studies; Genetic Predisposition to Disease; Heterozygote; Humans; Models, Genetic; Polymorphism, Single Nucleotide

Calpain activity has been implicated in several cellular processes such as cell signaling, apoptosis, exocytosis, mitochondrial metabolism and cytoskeletal remodeling. Evidence has indicated that the impairment of calpain expression and the activity of different calpain family members are involved in diverse pathologies. Calpain-10 has been implicated in the development of type 2 diabetes, and polymorphisms in the CAPN10 gene have been associated with an increased risk of developing this disease. The present work focused on the molecular biology of calpain-10, supporting its key participation in glucose metabolism. Current knowledge regarding the role of calpain-10 in the development of type 2 diabetes mellitus and diabetes-related diseases is additionally reviewed.

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Glucose; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Polymorphism, Genetic

Summary Calpain 10 (CAPN10) variants have been associated with the genetic susceptibility to type 2 diabetes (T2D). In the present case-control study, we analysed the distribution of SNP-19 insertion/deletion (I/D) polymorphism in a total of 607 samples (103 T2D cases and 102 healthy controls) from Brahmin; (100 T2D cases and 100 healthy controls) from Bania and (100 T2D cases and 102 healthy controls) from Jat Sikh ethnic groups of the North-West Indian population. Increased frequency of I allele and II genotype was found in T2D in Brahmin ethnic group [P = 0·003, OR = 2·83 (1·43-5·61 at 95% CI)]. Significant correlation between II genotype and body mass index (BMI) was also observed [P = 0·003, OR = 3·31 (1·52-7·20 at 95% CI)]. No association for the genotypes and alleles was seen in Banias and Jat Sikhs. Our data suggests that SNP-19 I/D variation in the CAPN10 gene is modulated by ethnicity and influences the susceptibility to T2D in the North-West Indian population. We also performed a meta-analysis of relevant studies to assess the validity of this association. Data from 13 case-control studies with 15 760 samples comprising of 8395 T2D cases and 7365 controls were finally analysed. Significant heterogeneity between individual studies was evident in dominant and codominant models. The results of present meta-analysis indicate an association of T2D with carriers of DD genotype of CAPN10 I/D polymorphism. However, further analyses on a larger sample size are required to establish a conclusive association in meta-analysis.

Topics: Body Mass Index; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Humans; India; Polymorphism, Single Nucleotide

Polycystic ovary syndrome (PCOS) is a highly complex endocrine disorder, characterized by hyperandrogenemia, menstrual irregularities and polycystic ovaries. A strong genetic component to the etiology of PCOS is evident. However, due to the genetic and phenotypic heterogeneity of PCOS and the lack of insufficiently large cohorts, studies to identify specific contributing genes to date have yielded only few conclusive results. In this review we discuss the current status of the genetic analysis of PCOS including the results of numerous association studies with candidate genes involved in TGF-β and insulin signaling, type 2 diabetes mellitus and obesity susceptibility. Furthermore, we address current challenges in genetic studies of PCOS, and the promise of new approaches, including genome-wide association studies and next-generation sequencing.

Topics: Alpha-Ketoglutarate-Dependent Dioxygenase FTO; Calpain; Diabetes Mellitus, Type 2; Female; Fibrillins; Genetic Predisposition to Disease; Genome-Wide Association Study; Humans; Insulin; Insulin Receptor Substrate Proteins; Microfilament Proteins; Polycystic Ovary Syndrome; Polymorphism, Genetic; Proteins; Receptor, Insulin; Sex Hormone-Binding Globulin; Transcription Factor 7-Like 2 Protein

The multiple small-scale association studies of candidate genes for type 2 diabetes mellitus in the Chinese Han population have shown inconsistent results. Here, we performed a meta-analysis to evaluate the contribution of five candidate genes to the pathogenesis of type 2 diabetes in the Chinese Han population. We searched for relevant published papers and used STATA v.11.0 to perform a meta-analysis on six single-nucleotide polymorphisms in five genes-ADIPOQ-rs2241766 (SNP45) and -rs1501299 (SNP276), ADRB3-rs4994 (Trp64Arg), CAPN10-rs3792267 (SNP43), ENPP1-rs1044498 (K121Q), and PPARGC1A-rs8192678 (Gly482Ser)-in the Chinese Han population under an additive genetic model. The pooled odds ratios (95% confidence intervals and P-values) were 0.71 (0.60-0.83; P < 0.001) for ADIPOQ-rs2241766, 0.79 (0.64-0.97; P = 0.027) for ADIPOQ-rs1501299, 1.27 (1.07-1.51; P = 0.006) for ADRB3-rs4994, 0.79 (0.57-1.10; P = 0.163) for CAPN10-rs3792267, 1.41 (1.13-1.76; P = 0.003) for ENPP1-rs1044498, and 1.54 (1.34-1.81; P < 0.001) for PPARGC1A-rs8192678. There was high heterogeneity for ADIPOQ-rs2241766, ADIPOQ-rs1501299, and CAPN10-rs3792267 (I² = 74.9, 69.4, and 75.8%, respectively), but not for ADRB3-rs4994, ENPP1-rs1044498, and PPARGC1A-rs8192678 (I² = 0.0, 43.4, and 23.3%, respectively). Under an additive genetic model, the C allele of ADRB3-rs4994, the C allele of ENPP1-rs1044498, and the A allele of PPARGC1A-rs8192678 increase the risk of type 2 diabetes in the Chinese Han population.

Topics: Adiponectin; Asian People; Calpain; China; Diabetes Mellitus, Type 2; Genetic Association Studies; Genetic Predisposition to Disease; Heat-Shock Proteins; Humans; Models, Genetic; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Phosphoric Diester Hydrolases; Polymorphism, Single Nucleotide; Pyrophosphatases; Receptors, Adrenergic, beta-3; Transcription Factors

The purpose of this study was to approach the relation of SNP43, SNP44 locus, main haplotypes and haplotype combinations with type 2 diabetes mellitus (T2DM).. According to the theory and principles of systematic review, data from case-control studies regarding the association between calpain-10 (CAPN10) gene and T2DM were derived through electronic search of PubMed and Chinese journals databases. To gain a more precise estimation of the relationship, a stratified Meta-analysis with four subgroups was performed according to the races. Publication bias was also assessed.. The association with T2DM in different races was evaluated. In Mongoloid race, SNP43-G allele, G/G genotype and 111/221 haplotype combination showed notable association with T2DM with ORs (95%CI) as 1.368 (1.155 - 1.620), 1.437 (1.186 - 1.741) and 2.762 (1.287 - 5.927) respectively. In Caucasoid race, SNP44-C allele, 111/111 hapotype combination showed strong relationship with T2DM with ORs (95%CI) as 1.144 (1.023 - 1.278), 1.291(1.050 - 1.586) respectively. In Hybrid race, only one positive finding was obtained which was SNP44-C allele with OR (95%CI) as 1.653 (1.025 - 2.665).. SNP43-G allele, G/G genotype, 111/221 were risk factors to Mongoloid race. And SNP-C allele, 111/111 haplotype combination were risk factors to Caucasoid race, and SNP44-C allele to Hybrid race.

Topics: Asian People; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Humans; Hybridization, Genetic; Odds Ratio; Polymorphism, Genetic; Publication Bias; Risk Factors; White People

CAPN10, which encodes the cysteine protease calpain 10, was the first type 2 diabetes mellitus (T2DM) susceptibility gene identified through a genome-wide scan followed by positional cloning. A haplotype combination comprising three intronic CAPN10 single-nucleotide polymorphisms (UCSNP-43, -19, and -63) was associated with increased risk of T2DM in the population in which linkage was first found. Follow-up studies have been published from a wide range of populations; some confirm the original finding, but some do not. The exact function of calpain 10 remains to be determined, but it has been implicated both in glucose transporter 4 translocation to the cell membrane, regulation of pancreatic insulin secretion, and pancreatic beta-cell apoptosis. This article reviews the genetic evidence for the association between CAPN10 and T2DM. The latest understanding of the biologic function of calpain 10 is discussed, along with results from recent genome-wide association studies that have failed to put CAPN10 among the top signals.

Topics: Apoptosis; Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Glucose Transporter Type 4; Haplotypes; Humans; Insulin; Insulin Secretion; Insulin-Secreting Cells; Polymorphism, Single Nucleotide; Translocation, Genetic

Calpains, particularly conventional dimeric calpains, have claimed to be involved in the cell degeneration processes that characterize numerous disease conditions linked to dysfunctions of cellular Ca2+ homeostasis. The evidence supporting their involvement has traditionally been indirect and circumstantial, but recent work has added more solid evidence supporting the role of ubiquitous dimeric calpains in the process of neurodegeneration. The only disease condition in which a calpain defect has been conclusively involved concerns an atypical monomeric calpain: the muscle specific calpain-3, also known as p94. Inactivating defects in its gene cause a muscular dystrophy termed LGMD-2A. The molecular mechanism by which the absence of the proteolytic activity of calpain-3 causes the dystrophic process is unknown. Another atypical calpain, which has been characterized recently as a Ca2(+)-dependent protease, calpain 10, appears To be involved in the etiology of type 2 diabetes. The involvement has been inferred essentially from genetic evidence. Also in the case of type 2 diabetes the molecular mechanisms that could link the disease to calpain 10 are unknown.

Topics: Animals; Calcium; Calcium-Binding Proteins; Calpain; Connectin; Diabetes Mellitus, Type 2; Humans; Muscle Proteins; Muscular Dystrophies, Limb-Girdle; Neurodegenerative Diseases; Protein Kinases

Diabetes mellitus is one of the most common endocrine disorders. It affects almost 6% of the world's population, and its prevalence continues to increase. The causes of diabetes mellitus are multifactorial, and in the general population both genetic and environmental factors contribute evenly to its development. Several genes have been consistently associated with type 2 diabetes mellitus; however, it is not clear how many of those translate into increased cardiovascular disease risk. Recent evidence suggests that genetic variation at the CALPN10, FABP4, GK, GST, PPARA, and PPARG loci may confer higher cardiovascular disease risk in patients with type 2 diabetes mellitus. However, the evidence is scattered and inconclusive and its translation into practical clinical testing will require studies properly designed to examine not only simple genetic associations but also gene-gene and gene-environment interactions.

Topics: Adipose Tissue; Calpain; Coronary Artery Disease; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Disease Progression; Fatty Acid-Binding Proteins; Genetic Predisposition to Disease; Genetic Variation; Genotype; Glutathione Transferase; Humans; Oxidative Stress; Polymorphism, Genetic; PPAR gamma; Smoking

Type 2 diabetes is a complex polygenic metabolic disorder of epidemic proportions. This review provides a brief overview of the susceptibility genes in type 2 diabetes that primarily affect pancreatic 3 cells, with emphasis on their function and most relevant polymorphisms. We focus on calpain 10, the only susceptibility gene identified thus far through a positional cloning approach in subjects with diabetes.

Topics: Autoantigens; Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Humans; Insulin-Secreting Cells; Membrane Proteins; Polymorphism, Genetic; Protein Tyrosine Phosphatases; Receptor-Like Protein Tyrosine Phosphatases, Class 8

Topics: Calpain; Diabetes Complications; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Haplotypes; Humans; Polymorphism, Single Nucleotide; Protease Inhibitors

Type 2 diabetes mellitus (T2DM) can lead to death without treatment and it has been predicted that the condition will affect 215 million people worldwide by 2010. T2DM is a multifactorial disorder whose precise genetic causes and biochemical defects have not been fully elucidated, but at both levels, calpains appear to play a role. Positional cloning studies mapped T2DM susceptibility to CAPN10, the gene encoding the intracellular cysteine protease, calpain 10. Further studies have shown a number of noncoding polymorphisms in CAPN10 to be functionally associated with T2DM while the identification of coding polymorphisms, suggested that mutant calpain 10 proteins may also contribute to the disease. Here we review recent studies, which in addition to the latter enzyme, have linked calpain 5, calpain 3, and its splice variants, calpain 2 and calpain 1 to T2DM-related metabolic pathways along with T2DM-associated phenotypes, such as obesity and impaired insulin secretion, and T2DM-related complications, such as epithelial dysfunction and diabetic cataract.

Topics: Animals; Calpain; Diabetes Mellitus, Type 2; Genetic Linkage; Humans

Throughout the last decade, molecular genetic studies of non-autoimmune diabetes mellitus have contributed significantly to our present understanding of this disease's complex aetiopathogenesis. Monogenic forms of diabetes (maturity-onset diabetes of the young, MODY) have been identified and classified into MODY1-6 according to the mutated genes that by being expressed in the pancreatic beta-cells confirm at the molecular level the clinical presentation of MODY as a predominantly insulin secretory deficient form of diabetes mellitus. Genomewide linkage studies of presumed polygenic type 2 diabetic populations indicate that loci on chromosomes 1q, 5q, 8p, 10q, 12q and 20q contain susceptibility genes. Yet, so far, the only susceptibility gene, calpain-10 (CAPN10), which has been identified using genomewide linkage studies, is located on chromosome 2q37. Mutation analyses of selected 'candidate' susceptibility genes in various populations have also identified the widespread Pro12Ala variant of the peroxisome proliferator-activated receptor-gamma and the common Glu23Lys variant of the ATP-sensitive potassium channel, Kir6.2 (KCNJ11). These variants may contribute significantly to the risk type 2 diabetes conferring insulin resistance of liver, muscle and fat (Pro12Ala) and a relative insulin secretory deficiency (Glu23Lys). It is likely that, in the near future, the recent more detailed knowledge of the human genome and insights into its haploblocks together with the developments of high-throughput and cheap genotyping will facilitate the discovery of many more type 2 diabetes gene variants in study materials, which are statistically powered and phenotypically well characterized. The results of these efforts are likely to be the platform for major progress in the development of personalized antidiabetic drugs with higher efficacy and few side effects.

Topics: Age of Onset; Calpain; Chromosomes, Human; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Humans; Insulin; Islets of Langerhans; Muscle, Skeletal; Mutation; Potassium Channels, Inwardly Rectifying; PPAR gamma; Signal Transduction

Topics: Animals; Apoptosis; Calpain; Carbohydrate Metabolism; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Haplotypes; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Linkage Disequilibrium; Polymorphism, Single Nucleotide

In the last years type 2 diabetes has reached almost epidemic proportions. More than 170 million individuals are affected worldwide, about 6 million in Germany. Manifestation of type 2 diabetes is determined by both environmental factors such as lack of physical exercise and overeating and a genetic predisposition. Despite enormous efforts in medical research to identify susceptibility loci and high risk alleles, the genetics of common type 2 diabetes (non-MODY) remain unknown. To date, only a few susceptibility genes have been identified (such as PPARG, KCNJ11, CAPN10). However, replication of initial studies is often difficult. This can be explained by both locus and allelic heterogeneity as well as ethnic differences between different populations. Studies in genetically isolated populations such as the Pima Indians are advantageous to identify susceptibility alleles. Despite some recent advances, it is not possible to predict an individual's risk of type 2 diabetes based on the presence of a certain disease-risk allele.

Topics: Biomarkers; Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genetic Testing; Genetics, Population; Germany; Humans; Incidence; Internationality; Potassium Channels, Inwardly Rectifying; PPAR gamma; Risk Assessment; Risk Factors

A variation in the gene encoding the cysteine protease calpain 10 (CAPN10) was recently linked and associated with type 2 diabetes by positional cloning. This positional cloning was a follow-up investigation to the identification of a diabetes-linked region on human chromosome 2 identified by genome-wide scanning a few years earlier. In this paper we give a general background on the genetic studies performed on CAPN10 to date, and review the most recent studies on the functional role of calpain 10.. A haplotype or haplotype combination comprising three intronic single nucleotide polymorphisms (UCSNP-43, 19, and 63) were associated with a threefold increased risk of type 2 diabetes in the population in which linkage was first found. Another polymorphism, UCSNP-44, which is in linkage disequilibrium with a coding single-nucleotide polymorphism (Thr504Ala), has subsequently been associated with type 2 diabetes in extensive meta-analyses. Meanwhile, initial studies probing the possible role of calpain-10, completely unknown at the time, are now being pursued, both in isolated cells and humans.. The positional cloning of CAPN10 as a candidate gene for type 2 diabetes has been particularly fruitful. Not only has it identified an important and surprising piece of the puzzle underlying the development of diabetes, but it has also modelled and paved the way for investigations concerning complex genetic diseases other than type 2 diabetes.

Topics: Calpain; Chromosomes, Human, Pair 2; Cloning, Molecular; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Haplotypes; Humans; Polymorphism, Single Nucleotide

Topics: Alzheimer Disease; Calpain; Cataract; Diabetes Mellitus, Type 2; Female; Humans; Isoenzymes; Male; Muscle Proteins; Muscular Dystrophies, Limb-Girdle; Mutation

Topics: Adiponectin; Amyloid; Calpain; Diabetes Mellitus, Type 2; Drug Design; Genetic Predisposition to Disease; Genetic Testing; Genome, Human; Hepatocyte Nuclear Factor 4; Humans; Islet Amyloid Polypeptide; Pharmacogenetics; Polymorphism, Single Nucleotide; Potassium Channels, Inwardly Rectifying; PPAR gamma

Variation in the calpain 10 gene has recently been shown to be associated with type 2 diabetes by positional cloning. Since then, studies on calpain 10 have been started in correlation with diabetes and insulin-mediated signaling. In this review, the activation mechanism of calpain by calcium ions, which is essential to understand its physiological functions, is discussed on the basis of recent X-ray structural analyses. Further, special features of the structure of calpain 10 that differ from those of typical micro - or m-calpain used in most studies are summarized together with discussion of the physiological function of calpain with respect to type 2 diabetes.

Topics: Calcium; Calpain; Cloning, Molecular; Diabetes Mellitus, Type 2; Humans; Models, Molecular; Protein Conformation

The follow-up studies to the original report of association of variation at calpain 10 (CAPN10) with type 2 diabetes in the Mexican-American population of Starr County, Texas, encompass a broad range of science. There are association studies on genetic variation at CAPN10 in different human populations over a range of phenotypes related to type 2 diabetes, physiological studies on the biological functions of calpain proteases, and evolutionary studies on CAPN10 and the NIDDM1 region. We review here the studies published to date on CAPN10, as well as the latest findings from positional cloning studies on a number of other complex disorders. Collectively, these studies provide perspective on the challenges of moving from the linkage mapping and positional cloning studies on which we have been focused to an understanding of the biology shaping the relationship of genotype to phenotype at loci influencing susceptibility to complex disorders like type 2 diabetes.

Topics: Calpain; Chromosome Mapping; Cloning, Molecular; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genetic Variation; Humans

Calpains are calcium-modulated proteases which respond to Ca2+ signals by removing limited portions of protein substrates, thereby irreversibly modifying their function(s). Members of this protease family are present in a variety of organisms ranging from mammals to plants; some of them are ubiquitously expressed, while others are tissue specific. Although calpains are apparently involved in a multitude of physiological and pathological events, their functions are still poorly understood. In two cases, however, the alteration of a member of the calpain family has been clearly identified as being responsible for a human disease: the loss of function of calpain 3 causes limb girdle muscular dystrophy type 2A, and mutations in the gene coding for calpain 10 have been shown to correlate with non-insulin-dependent diabetes.

Topics: Calpain; Diabetes Mellitus, Type 2; Humans; Isoenzymes; Muscle Proteins; Muscular Dystrophies; Mutation

Type 2 diabetes mellitus (T2DM) is characterized by defects in haepatic glucose production, insulin action and insulin secretion, which can also lead to a variety of secondary disorders. The disease can lead to death without treatment and it has been predicted that T2DM will affect 215 million people world-wide by 2010. T2DM is a multifactorial condition whose precise genetic causes and biochemical defects have not been fully elucidated but at both levels, calpains appear to play a role. Positional cloning studies mapped T2DM susceptibility to CAPN10, the gene encoding the intracellular cysteine protease, calpain 10. Further studies have shown a number of non-coding polymorphisms in CAPN10 to be functionally associated with T2DM whilst the identification of coding polymorphisms, suggested that mutant calpain 10 proteins may also contribute to the disease. The presence of both calpain 10 and its mRNA have been demonstrated in tissues from several mammalian species whilst calpain 10 appears to be associated with pathways involved in glucose metabolism, insulin secretion and insulin action. It appears that other calpains may also participate in these pathways and here we present an overview of recent studies on calpains and their putative role in T2DM.

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Linkage; Humans; Protein Structure, Tertiary

Type 2 diabetes mellitus represents a multifactorial, heterogeneous group of disorders, which result from defects in insulin secretion, insulin action, or both. The prevalence of type 2 diabetes has increased dramatically worldwide over the past several decades, a trend that has been heavily influenced by the relatively recent changes in diet and physical activity levels. There is also strong evidence supporting a genetic component to type 2 diabetes susceptibility and several genes underlying monogenic forms of diabetes have already been identified. However, common type 2 diabetes is likely to result from the contribution of many genes interacting with different environmental factors to produce wide variation in the clinical course of the disease. Not surprisingly, the etiologic complexity underlying type 2 diabetes has made identification of the contributing genes difficult. Current therapies in the management of type 2 diabetes include lifestyle intervention through diet modification and exercise, and oral or injected hypoglycemic agents; however, not all individuals with type 2 diabetes respond in the same way to these treatments. Because of variability in the clinical course of the disease and in the responsiveness to pharmacologic therapies, identification and characterization of the genetic variants underlying type 2 diabetes susceptibility will be important in the development of individualized treatment. Findings from linkage analyses, candidate gene studies, and animal models will be valuable in the identification of novel pathways involved in the regulation of glucose homeostasis, and will augment our understanding of the gene-gene and gene-environment interactions, which impact on type 2 diabetes etiology and pathogenesis. In addition, identification of genetic variants that determine differences in antidiabetic drug responsiveness will be useful in assessing a first-line pharmacologic therapy for diabetic patients.

Topics: Calpain; Cloning, Molecular; Diabetes Mellitus, Type 2; Diet; Environment; Exercise; Genetic Predisposition to Disease; Humans; Hypoglycemic Agents; Life Style; PPAR gamma

Topics: Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Genetic Linkage; Genetic Predisposition to Disease; Humans; Polymorphism, Single Nucleotide; Racial Groups; Reproducibility of Results

Topics: Adiponectin; Amyloid; Animals; Calpain; Chromosomes, Human, Pair 1; Chromosomes, Human, Pair 20; Diabetes Mellitus, Type 2; Environment; Genetic Linkage; Genetic Predisposition to Disease; Genome, Human; Humans; Intercellular Signaling Peptides and Proteins; Islet Amyloid Polypeptide; Mutation; Polymorphism, Single Nucleotide; Proteins; Receptors, Adrenergic, beta-3; Receptors, Cytoplasmic and Nuclear; Transcription Factors

Both type 2 diabetes mellitus (T2DM) and insulin resistance are complex traits in which multiple gene effects and metabolic and environmental factors combine to contribute to the overall pathogenesis of these conditions. This complexity has complicated the search for susceptibility genes and has led to different but complementary approaches being used for the detection of gene effects. These include the study of monogenic cases of insulin resistance and T2DM, association studies of candidate genes and genome-wide scans. The peroxisome proliferator-activated receptor gamma (PPARgamma) and calpain-10 (CAPN10) genes have recently been identified as T2DM susceptibility genes, and the lessons learnt from these studies are helping to shape future strategies to search for additional susceptibility genes in T2DM and insulin resistance.

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genome; Humans; Insulin Resistance; Receptors, Cytoplasmic and Nuclear; Transcription Factors

Topics: Animals; Calpain; Carbohydrate Metabolism; Chromosome Mapping; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genetic Testing; Humans; Linkage Disequilibrium; Polymorphism, Single Nucleotide

Topics: Adiponectin; Animals; Calpain; Chromosome Mapping; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Haplotypes; Humans; Intercellular Signaling Peptides and Proteins; Linkage Disequilibrium; Polymorphism, Single Nucleotide; Proteins; Receptors, Cytoplasmic and Nuclear; Transcription Factors

Positional cloning studies conducted on a region of chromosome 2q providing evidence for linkage to type 2 diabetes implicated genetic variation at the calpain-10 gene (CAPN10) in susceptibility to type 2 diabetes. The variants identified in these studies are located in introns, rather than in coding sequence. It was proposed that the cumulative effects of a combination of variants, rather than variation at a single site, increase the risk of type 2 diabetes. Confirmation of the hypothesis that non-coding sequence variation in CAPN10 affects susceptibility to type 2 diabetes has implications for how we search for susceptibility variants and interpret results of positional cloning studies for complex disorders, and suggests a new pathway in glucose homeostasis. We review the results of follow-up studies on the CAPN10 finding, and consider the issues inherent in conclusively establishing that particular genetic variation affects a complex phenotype.

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Humans

Topics: Adipocytes; Animals; Body Temperature Regulation; Calpain; Chromosome Mapping; Diabetes Mellitus, Type 2; Genetic Linkage; Genetic Predisposition to Disease; Humans; Islets of Langerhans; Mice; Receptors, Cytoplasmic and Nuclear; Transcription Factors

The number of mammalian calpain protease family members has grown to 14 on last count. Overactivation of calpain 1 and calpain 2 (and their small subunit) has long been tied to acute neurological disorders (e.g. stroke and traumatic brain injury) and recently to Alzheimer's disease. Loss-of-function mutations of the calpain 3 gene have now been identified as the cause of limb-girdle muscular dystrophy 2A. Calpain 10 was recently identified as a susceptibility gene for type 2 diabetes, whereas calpain 9 appears to be a gastric cancer suppressor. This review describes our current understanding of the calpain family members and their mechanistic linkages to the aforementioned diseases as well as other emerging pathological conditions.

Topics: Alzheimer Disease; Animals; Calpain; Cataract; Diabetes Mellitus, Type 2; Disease; EF Hand Motifs; Humans; Multigene Family; Muscular Dystrophies; Nervous System Diseases; Stomach Neoplasms

Type 2 diabetes is a classic example of a complex disorder. It is strongly familial, but clearly arises as a consequence of the actions and interactions of many genetic and non-genetic factors. Type 2 diabetes is a common disorder, affecting 16 million Americans. It has a major impact on public health expenditures with more than 1 in 10 health care dollars spent on treating diabetes and its complications. Although a variety of therapies can be useful in treatment of type 2 diabetes, we remain sufficiently ignorant of the genetic risk factors to believe that identifying them will lead to better understanding of the primary physiology of the disorder, as well as to more specific and effective therapies. Moreover, identification of genetic risk factors may improve our ability to characterize more specific non-genetic risk factors for this disease that could be the targets for cost-effective prevention strategies. This manuscript reviews the challenges we face in moving from the linkage mapping of susceptibility genes for type 2 diabetes toward the identification of the genetic variation that actually affects risk to this disorder. I illustrate many of the challenges in designing, conducting and interpreting these studies by reviewing recent research conducted on the calpain-10 gene, implicated in positional cloning studies as a candidate gene for type 2 diabetes.

Topics: Adolescent; Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genetic Variation; Humans; Models, Genetic

Type 2 diabetes refers to a group of disparate metabolic diseases, which are typically characterized by insulin resistance in peripheral tissues, together with impaired insulin secretion from pancreatic beta-cells. The complexity of type 2 diabetes is related to factors such as genetic heterogeneity, interactions between genes, and the modulating role played by the environment. Recent progress has included defining the molecular basis of monogenic forms of type 2 diabetes, such as familial partial lipodystrophy and the subtypes of maturity-onset diabetes of the young (MODY), and also the identification of chromosomal regions that may harbor type 2 diabetes susceptibility genes. Many common variants in functional and positional candidate genes, including ADRB3, PPARG, ENPP1, and CAPN10, have also been studied for their possible role as determinants of type 2 diabetes, with varying levels of agreement between studies. The availability of a relatively complete sequence of the human genome will increase the amount of genetic information that can be used to evaluate hypotheses for the genetic basis of type 2 diabetes. To make sense of human type 2 diabetes in the post-genomic era, it is essential to have well-defined phenotypes in addition to sufficient numbers of individuals with the appropriate pedigree structure from families and/or communities.

Topics: Animals; Calpain; Chromosome Mapping; Diabetes Mellitus, Type 2; Disease Models, Animal; Environment; Genetic Predisposition to Disease; Humans; Lipodystrophy; Mutation; Native Hawaiian or Other Pacific Islander; Racial Groups

Topics: Amyloid; Animals; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Calpain; Chromosome Mapping; Diabetes Mellitus, Type 2; Disease Susceptibility; DNA-Binding Proteins; Genome, Human; Glucokinase; Hepatocyte Nuclear Factor 4; Humans; Insulin; Islet Amyloid Polypeptide; Microsatellite Repeats; Phosphoproteins; Polymorphism, Single Nucleotide; Receptors, Cytoplasmic and Nuclear; Transcription Factors

Topics: Calpain; Chromosome Mapping; Chromosomes, Human, Pair 2; Cloning, Molecular; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genome, Human; Haplotypes; Humans; Linkage Disequilibrium; Polymorphism, Single Nucleotide

The aim of the present study was to investigate possible associations of the single-nucleotide variants in six genes encoding the key molecules mediating the metformin pharmacodynamic effect with the response to treatment with metformin in patients with type 2 diabetes.. One hundred forty-eight drug-naïve patients with type 2 diabetes were included in the study. PRKAA1 rs249429, STK11 rs741765, PCK1 rs4810083, PPARGC1A rs10213440, HNF1A rs11086926, and CAPN10 rs3792269 variants were genotyped. The outcomes of the study were treatment success defined by achieving HbA1c <7 % and absolute reduction in HbAlc after 6-month metformin therapy. The relationships between genotypes and outcomes were evaluated in multivariate logistic and linear models. The level of statistical significance after Bonferroni correction was predefined as p<0.0083.. The minor G-allele of CAPN10 rs3792269 A>G polymorphism was significantly associated with less treatment success with an odds ratio of 0.27 (95 % CI 0.12-0.62, p=0.002) per variant allele. When the reduction in HbA1c was analyzed as a quantitative trait, G-allele was nominally associated with a smaller reduction in HbA1c (per allele β=-0.26, 95 % CI -0.50 to -0.02, p=0.032). The reduction in HbA1c in minor allele carriers (24 % of study population) was smaller by 0.3 % in comparison with the major allele homozygotes.. The present study provides the first observation of an association between a variant in CAPN10 gene and the response to metformin therapy in patients with type 2 diabetes. This observation needs to be replicated in further studies in different populations.

Topics: AMP-Activated Protein Kinase Kinases; AMP-Activated Protein Kinases; Calpain; Diabetes Mellitus, Type 2; Female; Genetic Variation; Glycated Hemoglobin; Hepatocyte Nuclear Factor 1-alpha; Humans; Hypoglycemic Agents; Intracellular Signaling Peptides and Proteins; Male; Metformin; Middle Aged; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Phosphoenolpyruvate Carboxykinase (GTP); Protein Serine-Threonine Kinases; Transcription Factors; Treatment Outcome

Platelets from patients with type 2 diabetes mellitus display hyperaggregability and increased thrombogenic potential.. In platelets from patients with type 2 diabetes mellitus, we found enhanced tyrosine nitration and inactivation of the sarcoplasmic endoplasmic reticulum Ca2+-ATPase (SERCA-2), elevated platelet [Ca2+]i, and activation of mu-calpain. The tyrosine nitration of SERCA-2 and the activation of mu-calpain in vitro in platelets from healthy volunteers could be evoked in vitro by peroxynitrite. Platelet endothelial cell adhesion molecule-1 was identified as a mu-calpain substrate; its in vitro degradation was stimulated by peroxynitrite and prevented by calpain inhibitors. Calpain activation also was linked to hyperresponsiveness to thrombin and the loss of platelet sensitivity to nitric oxide synthase inhibitors. Platelets from patients with type 2 diabetes mellitus (hemoglobin A1c >6.6%) contained little or no intact platelet endothelial cell adhesion molecule-1, whereas degradation products were detectable. The peroxisome proliferator-activated receptor-gamma agonist rosiglitazone increased SERCA-2 expression in megakaryocytes, and treating patients with type 2 diabetes mellitus with rosiglitazone for 12 weeks increased platelet SERCA-2 expression and Ca2+-ATPase activity, decreased SERCA-2 tyrosine nitration, and normalized platelet [Ca2+]i. Rosiglitazone also reduced mu-calpain activity, normalized platelet endothelial cell adhesion molecule-1 levels, and partially restored platelet sensitivity to nitric oxide synthase inhibition.. These data identify megakaryocytes/platelets as additional cellular targets for peroxisome proliferator-activated receptor-gamma agonists and highlight potential benefits of rosiglitazone therapy in cardiovascular diseases.

Topics: Adult; Aged; Blood Platelets; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Male; Megakaryocytes; Middle Aged; Nitro Compounds; Platelet Endothelial Cell Adhesion Molecule-1; PPAR gamma; Rosiglitazone; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Thiazolidinediones

Vascular endothelial dysfunction (VED) is the onset event of cardiovascular complications in type 2 diabetes mellitus. Ginsenoside Rg1 (Rg1) can improve the cardiovascular system, but its mechanism in diabetic vascular endothelial dysfunction has received little attention.. Male calpain-1-knockout and wild-type C57BL/6 J mice were intraperitoneally injected with streptozotocin and treated with Rg1 (10 and 20 mg/kg) for 8 weeks. Human aortic endothelial cells (HAECs) were incubated with high glucose (HG) and were pretreated with Rg1 (10, 20 μM), MDL-28170 (calpain-1 inhibitor), LY-333531 (PKC-β inhibitor), NAC (ROS inhibitor) and calpain-1 overexpression. Then, factors related to mitochondrial dysfunction, oxidative stress and VED were measured.. The administration of Rg1 and calpain-1 knockout ameliorated diabetic mitochondrial dysfunction, oxidative stress and VED and inhibited the calpain-1/ROS/PKC-β axis. LY-333531 and NAC treatment restored destructive endothelium-dependent vasodilation in mice with diabetes, while pyrogallol (ROS agonist), PMA (PKC-β agonist) or L-NAME (eNOS inhibitor) treatment abrogated the protective effect of Rg1 against diabetic endothelial dysfunction. The administration of Rg1, MDL-28170, LY-333531 and NAC improved mitochondrial dysfunction, oxidative stress and VED, whereas the overexpression of calpain-1 amplified mitochondrial dysfunction, oxidative stress and VED and further upregulated the expression of PKC-β in HAECs exposed to HG. Overexpression of calpain-1 abrogated the protective effect of Rg1 against HG-induced oxidative stress and VED.. These findings reveal that Rg1 can protect against VED by suppressing the calpain-1/ROS/PKC-β axis and alleviating the development of mitochondrial dysfunction and oxidative stress.

Topics: Animals; Calpain; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Endothelial Cells; Endothelium, Vascular; Humans; Male; Mice; Mice, Inbred C57BL; Oxidative Stress; Reactive Oxygen Species; Vascular Diseases

Topics: Adult; Biomarkers; Blood Glucose; Calpain; Diabetes Mellitus, Type 2; DNA Methylation; Glycated Hemoglobin; Humans; Kidney Function Tests; Lipids; Prediabetic State; Risk Factors

Patients with type 2 diabetes (T2DM) have a prothrombotic state that needs to be fully clarified; microparticles (MPs) have emerged as mediators and markers of this condition. Thus, we investigate, in vivo, in T2DM either with good (HbA1c ≤ 7.0%; GGC) or poor (HbA1c > 7.0%; PGC) glycemic control, the circulating levels of MPs, and in vitro, the molecular pathways involved in the release of MPs from platelets (PMP) and tested their pro-inflammatory effects on THP-1 transformed macrophages.. In 59 T2DM, and 23 control subjects with normal glucose tolerance (NGT), circulating levels of CD62E+, CD62P+, CD142+, CD45+ MPs were determined by flow cytometry, while plasma levels of ICAM-1, VCAM-1, IL-6 by ELISA. In vitro, PMP release and activation of isolated platelets from GGC and PGC were investigated, along with their effect on IL-6 secretion in THP-1 transformed macrophages.. We found that MPs CD62P. These results identify PAR-4 as a mediator of platelet activation, microparticle release, and inflammation, in poorly controlled T2DM.

Topics: Biomarkers; Blood Glucose; Blood Platelets; Calcium; Calpain; Case-Control Studies; Cell-Derived Microparticles; Diabetes Mellitus, Type 2; Female; Glycated Hemoglobin; Humans; Interleukin-6; Macrophages; Male; Middle Aged; Platelet Activation; Receptors, Thrombin; THP-1 Cells; Thrombin

Diabetes mellitus is a major risk factor for cardiovascular disease. Platelets from diabetic patients are hyperreactive and release microparticles that carry activated cysteine proteases or calpains. Whether platelet-derived calpains contribute to the development of vascular complications in diabetes is unknown. Here we report that platelet-derived calpain1 (CAPN1) cleaves the protease-activated receptor 1 (PAR-1) on the surface of endothelial cells, which then initiates a signaling cascade that includes the activation of the tumor necrosis factor (TNF)-α converting enzyme (TACE). The latter elicits the shedding of the endothelial protein C receptor and the generation of TNF-α, which in turn, induces intracellular adhesion molecule (ICAM)-1 expression to promote monocyte adhesion. All of the effects of CAPN1 were mimicked by platelet-derived microparticles from diabetic patients or from wild-type mice but not from CAPN1

Topics: ADAM17 Protein; Adult; Animals; Blood Platelets; Calpain; Case-Control Studies; Cell-Derived Microparticles; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Endothelial Cells; Endothelial Protein C Receptor; Female; Humans; Intercellular Adhesion Molecule-1; Male; Mice, Inbred C57BL; Mice, Knockout; Middle Aged; Receptor, PAR-1; Tumor Necrosis Factor-alpha; Vasculitis

Topics: Adult; Alleles; Blood Glucose; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Gene Expression; Gene Frequency; Genotype; Glutathione Transferase; Glycated Hemoglobin; Humans; Hyperglycemia; INDEL Mutation; Insulin Resistance; Male; Middle Aged; Polymorphism, Single Nucleotide

CAPN10 gene is associated with type 2 diabetes (T2D). Specific members of the calpain system (CAPN1, CAPN2 and CAPN10) are implicated in glucose metabolism. The aim of this study was to evaluate the calpain activity in leukocytes of control subjects and patients with T2D and its association with the calpain family members involved in glucose metabolism and with biochemical parameters that are altered in T2D.. Calpain activity under extracellular glucose concentrations (70-280 mg/dL) was evaluated in leukocytes from subjects with and without T2D. Protein and mRNA levels of CAPN1, CAPN2 and CAPN10 were evaluated. Calpain inhibitors assays were performed in leukocytes from subjects without T2D to evaluate glucose uptake. Calpain activity at 100 mg/dL glucose was correlated with biochemical parameters by multivariate regression.. Calpain activity in control subjects increased with extracellular glucose concentration in a dose-dependent manner, showing a negative association with HbA1c levels and total amount of CAPN10 protein. In contrast, calpain activity is decreased in patients with T2D and do not respond to changes in glucose concentration. A reduction of CAPN1 autolytic fragments were observed in the subjects with diabetes. Calpain inhibitors decreased calpain activity but did not altered glucose uptake in leukocytes.. Calpain activity induced by glucose in leukocytes was associated with biochemical markers of glucose metabolism and with CAPN10 protein abundance. Calpain activity is low in subjects with T2D. Thus, calpain activity induced by extracellular glucose in leukocytes could be a potential marker for T2D early risk detection.

Topics: Adult; Aged; Biomarkers; Calpain; Diabetes Mellitus, Type 2; Female; Glucose; Homeostasis; Humans; Leukocytes; Male; Middle Aged

The role of non-cardiomyocytes in diabetic cardiomyopathy has not been fully addressed. This study investigated whether endothelial cell calpain plays a role in myocardial endothelial injury and microvascular rarefaction in diabetes, thereby contributing to diabetic cardiomyopathy.. Endothelial cell-specific Capns1-knockout (KO) mice were generated. Conditions mimicking prediabetes and type 1 and type 2 diabetes were induced in these KO mice and their wild-type littermates. Myocardial function and coronary flow reserve were assessed by echocardiography. Histological analyses were performed to determine capillary density, cardiomyocyte size and fibrosis in the heart. Isolated aortas were assayed for neovascularisation. Cultured cardiac microvascular endothelial cells were stimulated with high palmitate. Angiogenesis and apoptosis were analysed.. Endothelial cell-specific deletion of Capns1 disrupted calpain 1 and calpain 2 in endothelial cells, reduced cardiac fibrosis and hypertrophy, and alleviated myocardial dysfunction in mouse models of diabetes without significantly affecting systemic metabolic variables. These protective effects of calpain disruption in endothelial cells were associated with an increase in myocardial capillary density (wild-type vs Capns1-KO 3646.14 ± 423.51 vs 4708.7 ± 417.93 capillary number/high-power field in prediabetes, 2999.36 ± 854.77 vs 4579.22 ± 672.56 capillary number/high-power field in type 2 diabetes and 2364.87 ± 249.57 vs 3014.63 ± 215.46 capillary number/high-power field in type 1 diabetes) and coronary flow reserve. Ex vivo analysis of neovascularisation revealed more endothelial cell sprouts from aortic rings of prediabetic and diabetic Capns1-KO mice compared with their wild-type littermates. In cultured cardiac microvascular endothelial cells, inhibition of calpain improved angiogenesis and prevented apoptosis under metabolic stress. Mechanistically, deletion of Capns1 elevated the protein levels of β-catenin in endothelial cells of Capns1-KO mice and constitutive activity of calpain 2 suppressed β-catenin protein expression in cultured endothelial cells. Upregulation of β-catenin promoted angiogenesis and inhibited apoptosis whereas knockdown of β-catenin offset the protective effects of calpain inhibition in endothelial cells under metabolic stress.. These results delineate a primary role of calpain in inducing cardiac endothelial cell injury and impairing neovascularisation via suppression of β-catenin, thereby promoting diabetic cardiomyopathy, and indicate that calpain is a promising therapeutic target to prevent diabetic cardiac complications.

Topics: Animals; Apoptosis; beta Catenin; Calpain; Diabetes Mellitus, Type 2; Diabetic Cardiomyopathies; Endothelial Cells; Fibroblasts; Gene Deletion; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardium; Myocytes, Cardiac; Neovascularization, Pathologic; Neovascularization, Physiologic; Signal Transduction

BACKGROUND This study aimed to investigate the association between the rs2975760 and rs3792267 single nucleotide polymorphisms (SNPs) of the calpain 10 (CAPN10) gene and gestational diabetes mellitus. MATERIAL AND METHODS The study included 138 patients with gestational diabetes mellitus and 152 healthy pregnant women. Venous blood was separated, and the DNA was extracted. The rs2975760 and rs3792267SNP polymorphisms of CAPN10 were detected using polymerase chain reaction (PCR). The frequencies of different genotypes in patients with gestational diabetes mellitus and healthy pregnant women were determined, and the relationship between different SNP genotypes and the risk of gestational diabetes mellitus was analyzed. RESULTS There were no significant differences in the frequencies of the TT, CT and CC genotypes of rs2975760 and the frequencies of the GG, AG and AA genotypes of rs3792267 between the women with gestational diabetes and the controls. Expression of rs2975760 and rs3792267 were not associated with the risk of gestational diabetes in the dominant model, recessive model, and additive model. However, grade B and grade D diabetes in the CC and TC genotypes of rs2975760 were significantly different from those in the TT genotype (P<0.05). Grade B and grade D diabetes in the AA and AG genotypes of rs3792267 were significantly different compared with those in the GG genotype (P<0.05), and allele A was significantly increased compared with allele G (P<0.05). CONCLUSIONS The rs2975760 and rs3792267 SNP polymorphisms of CAPN10 showed no significant association with the incidence of gestational diabetes mellitus and only a mild association with the severity.

Topics: Adult; Alleles; Asian People; Calpain; Case-Control Studies; China; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Polymorphism, Single Nucleotide; Pregnancy; Risk Factors

Megakaryocyte (MK)-derived miRNAs have been detected in platelets. Here, we analysed the expression of platelet and circulating miR-223, miR-26b, miR-126 and miR-140 that might be altered with their target mRNAs in type 2 diabetes mellitus (DM2). MiRNAs were isolated from leukocyte-depleted platelets and plasma samples obtained from 28 obese DM2, 19 non-DM obese and 23 healthy individuals. The effect of hyperglycaemia on miRNAs was also evaluated in MKs using MEG-01 and K562 cells under hyperglycaemic conditions after 8 hours up to four weeks. Quantitation of mature miRNA, pre-miRNAs and target mRNA levels (P2RY12 and SELP) were measured by RT-qPCR. To prove the association of miR-26b and miR-140 with SELP (P-selectin) mRNA level, overexpression or inhibition of these miRNAs in MEG-01 MKs was performed using mimics or anti-miRNAs, respectively. The contribution of calpain substrate Dicer to modulation of miRNAs was studied by calpain inhibition. Platelet activation was evaluated via surface P-selectin by flow cytometry. Mature and pre-forms of investigated miRNAs were significantly reduced in DM2, and platelet P2RY12 and SELP mRNA levels were elevated by two-fold at increased platelet activation compared to controls. Significantly blunted miRNA expressions were observed by hyperglycaemia in MEG-01 and K562-MK cells versus baseline values, while the manipulation of miR-26b and miR-140 expression affected SELP mRNA level. Calpeptin pretreatment restored miRNA levels in hyperglycaemic MKs. Overall, miR-223, miR-26b, miR-126 and miR-140 are expressed at a lower level in platelets and MKs in DM2 causing upregulation of P2RY12 and SELP mRNAs that may contribute to adverse platelet function.

Topics: Adult; Biomarkers; Blood Glucose; Blood Platelets; Calpain; Case-Control Studies; Circulating MicroRNA; Cross-Sectional Studies; Cysteine Proteinase Inhibitors; DEAD-box RNA Helicases; Diabetes Mellitus, Type 2; Dipeptides; Down-Regulation; Female; Humans; K562 Cells; Male; Megakaryocytes; Middle Aged; P-Selectin; Platelet Activation; Receptors, Purinergic P2Y12; Ribonuclease III; Time Factors; Transfection; Up-Regulation

Type 2 diabetes (T2D) is one of the most frequent mortality causes in western countries, with rapidly increasing prevalence. Anti-diabetic drugs are the first therapeutic approach, although many patients develop drug resistance. Most drug responsiveness variability can be explained by genetic causes. Inter-individual variability is principally due to single nucleotide polymorphisms, and differential drug responsiveness has been correlated to alteration in genes involved in drug metabolism (CYP2C9) or insulin signaling (IRS1, ABCC8, KCNJ11 and PPARG). However, most genome-wide association studies did not provide clues about the contribution of DNA variations to impaired drug responsiveness. Thus, characterizing T2D drug responsiveness variants is needed to guide clinicians toward tailored therapeutic approaches. Here, we extensively investigated polymorphisms associated with altered drug response in T2D, predicting their effects in silico. Combining different computational approaches, we focused on the expression pattern of genes correlated to drug resistance and inferred evolutionary conservation of polymorphic residues, computationally predicting the biochemical properties of polymorphic proteins. Using RNA-Sequencing followed by targeted validation, we identified and experimentally confirmed that two nucleotide variations in the CAPN10 gene-currently annotated as intronic-fall within two new transcripts in this locus. Additionally, we found that a Single Nucleotide Polymorphism (SNP), currently reported as intergenic, maps to the intron of a new transcript, harboring CAPN10 and GPR35 genes, which undergoes non-sense mediated decay. Finally, we analyzed variants that fall into non-coding regulatory regions of yet underestimated functional significance, predicting that some of them can potentially affect gene expression and/or post-transcriptional regulation of mRNAs affecting the splicing.

Topics: Calpain; Diabetes Mellitus, Type 2; Drug Resistance; Humans; Hypoglycemic Agents; Metformin; Molecular Docking Simulation; Polymorphism, Single Nucleotide; Receptors, G-Protein-Coupled; Regulatory Sequences, Nucleic Acid; RNA Processing, Post-Transcriptional

Genome-wide association studies have successfully identified over 70 loci associated with the risk of type 2 diabetes mellitus (T2DM) in multiple populations of European ancestry. However, the risk attributable to an individual variant is modest and does not yet provide convincing evidence for clinical utility. Association between these established genetic variants and T2DM in general populations is hitherto understudied in the isolated populations, such as the Uyghurs, resident in Hetian, far southern Xinjiang Uyghur Autonomous Region, China. In this case-control study, we genotyped 13 single-nucleotide polymorphisms (SNPs) at 10 genes associated with diabetes in 130 cases with T2DM and 135 healthy controls of Uyghur, a Chinese minority ethnic group. Three of the 13 SNPs demonstrated significant association with T2DM in the Uyghur population. There were significant differences between the T2DM patients and controls in the risk allele distributions of rs3792267 (CAPN10) (P = 0.002), rs1501299 (APM1) (P = 0.017), and rs3760776 (FUT6) (P = 0.031). Allelic carriers of rs3792267-A, rs1501299-T, and rs3760776-T had a 2.24-fold [OR (95% CI): 1.35-3.71], 0.59-fold [OR (95% CI): 0.39-0.91], 0.57-fold [OR (95% CI): 0.34-0.95] increased risk for T2DM respectively. We further confirmed that the cumulative risk allelic scores calculated from the 13 susceptibility loci for T2DM differed significantly between the T2DM patients and controls (P = 0.001), and the effect of obesity/overweight on T2DM was only observed in the subjects with a combined risk allelic score under a value of 17. This study observed that the SNPs rs3792267 in CAPN10, rs1501299 in APM1, and rs3760776 in FUT6 might serve as potential susceptible biomarkers for T2DM in Uyghurs. The cumulative risk allelic scores of multiple loci with modest individual effects are also significant risk factors in Uyghurs for T2DM, particularly among non-obese individuals. This is the first investigation having observed/found genetic variations on genetic loci functionally linked with glycosylation associated with the risk of T2DM in a Uyghur population.

Topics: Adiponectin; Alleles; Asian People; Calpain; Case-Control Studies; Demography; Diabetes Mellitus, Type 2; Ethnicity; Female; Fucosyltransferases; Genetic Predisposition to Disease; Genome-Wide Association Study; Humans; Male; Middle Aged; Obesity; Polymorphism, Single Nucleotide; Risk Factors; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Soluble insulin receptor (sIR), the ectodomain of the insulin receptor (IR), has been detected in human plasma and its concentration paralleled that of blood glucose. We have previously developed an in vitro model using HepG2 liver-derived cells, which mimics changes in sIR levels in plasma from diabetic patients and shows that calcium-dependent proteases cleave IR extracellularly (a process known as shedding). The present study aimed to reveal the mechanisms of IR cleavage.. Using the in vitro model, we investigated the molecular mechanisms of IR cleavage, which is accelerated by high-glucose treatment. We also analysed the relationship between IR cleavage and cellular insulin resistance, and the correlation between plasma sIR levels and insulin sensitivity, which was assessed by the euglycaemic-hyperinsulinaemic clamp technique.. Here, we determined that calpain 2, which is secreted into the extracellular space associated with exosomes, directly cleaved the ectodomain of the IRβ subunit (IRβ), which in turn promoted intramembrane cleavage of IRβ by γ-secretase. IR cleavage impaired insulin signalling and the inhibition of IR cleavage (by knockdown of calpain 2 and γ-secretase), restored IR substrate-1 and Akt, independent of IR. Furthermore, the glucose-lowering drug, metformin, prevented IR cleavage accompanied by inhibition of calpain 2 release in exosomes, and re-established insulin signalling. In patients with type 2 diabetes, plasma sIR levels inversely correlated with insulin sensitivity.. Sequential cleavage of IR by calpain 2 and γ-secretase may contribute to insulin signalling in cells and its inhibition may be partly responsible for the glucose-lowering effects of metformin. Thus, IR cleavage may offer a new mechanism for the aetiology of insulin resistance.

Topics: Amyloid Precursor Protein Secretases; Blotting, Western; Calpain; Diabetes Mellitus, Type 2; Enzyme-Linked Immunosorbent Assay; Exosomes; Hep G2 Cells; Humans; Immunoprecipitation; Insulin Resistance; Receptor, Insulin; RNA, Small Interfering

The islet in type 2 diabetes (T2D) shares many features of the brain in protein misfolding diseases. There is a deficit of β cells with islet amyloid derived from islet amyloid polypeptide (IAPP), a protein coexpressed with insulin. Small intracellular membrane-permeant oligomers, the most toxic form of IAPP, are more frequent in β cells of patients with T2D and rodents expressing human IAPP. β Cells in T2D, and affected cells in neurodegenerative diseases, share a comparable pattern of molecular pathology, including endoplasmic reticulum stress, mitochondrial dysfunction, attenuation of autophagy, and calpain hyperactivation. While this adverse functional cascade in response to toxic oligomers is well described, the sequence of events and how best to intervene is unknown. We hypothesized that calpain hyperactivation is a proximal event and tested this in vivo by β cell-specific suppression of calpain hyperactivation with calpastatin overexpression in human IAPP transgenic mice. β Cell-specific calpastatin overexpression was remarkably protective against β cell dysfunction and loss and diabetes onset. The critical autophagy/lysosomal pathway for β cell viability was protected with calpain suppression, consistent with findings in models of neurodegenerative diseases. We conclude that suppression of calpain hyperactivation is a potentially beneficial disease-modifying strategy for protein misfolding diseases, including T2D.

Topics: Animals; Calcium-Binding Proteins; Calpain; Diabetes Mellitus, Type 2; Female; Humans; Insulin-Secreting Cells; Islet Amyloid Polypeptide; Male; Mice; Mice, Transgenic

Pro-free radical oxidative stresses, as well as regulatory factors, are believed to be the key players in the development of diabetes and heart-related disorders such as myocardial infarction. The aim of the present study was to highlight the role of oxidative stress-responsive factors (reactive oxygen species [ROS], super oxide dismutase [SOD], and calpain-1) in type 2 diabetes and myocardial infarction.. A total of 100 type 2 diabetes patients with myocardial infarction and 50 normal individuals were selected for this analysis. The levels of ROS and activities of SOD in the serum were determined. Serum calpain-1 expression was checked using western blotting.. The serum level of ROS and the expression of calpain-1 were significantly higher while the activity of SOD was significantly lower in diabetic patients with myocardial infraction compared to normal individuals.. These findings suggest a possible link between decreased antioxidant (SOD) and increased ROS levels as well as calpain-1 expression, supporting the role of oxidative stress-regulatory factors in diabetes and myocardial infraction.

Topics: Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Myocardial Infarction; Oxidative Stress; Reactive Oxygen Species; Superoxide Dismutase

The calpain-10 gene is expressed primarily in tissues important in glucose metabolism; thus, some of its polymorphisms have been associated with type 2 diabetes. In this study, we examined the association between the calpain-10 single-nucleotide polymorphism (SNP)-43, SNP-19, and SNP-63 and type 2 diabetes in Mexican mestizos. We included 211 patients and 152 non-diabetic subjects. Polymerase chain reaction was used to identify alleles. We compared allele, genotype, haplotype, and diplotype frequencies between both groups and used the chi-square test to calculate the risk. The allele frequency of SNP-43 allele 1 was 70% in controls and 72% in patients; the GG, GA, and AA genotype frequencies were 48.7, 42.8, and 8.5% in controls and 51.2, 41.7, and 7.1% in patients, respectively. For SNP- 19, the prevalence of allele 1 (2R) was 32% in controls and 39% in patients. In controls, homozygosity (2R/2R) was 10.5%, heterozygosity was 42.8%, and 3R/3R was 46.7%; in cases, these values were 13.3, 50.7, and 36.0%, respectively. For SNP-63, the frequency of allele 1 was 87% in controls and 83% in patients; genotype frequencies in controls were 75.7% (CC), 23% (CT), and 1.3% (TT), and were 69.7, 27.5, and 2.8%, respectively for the cases. Genotype distributions were consistent with Hardy-Weinberg equilibrium. No significant intergroup differences for allele, genotype, haplotype, or diplotype frequencies were observed. We found no association between these polymorphisms and diabetes. However, our sample size was small, so the role of calpain-10 risk alleles should be further examined.

Topics: Body Mass Index; Calpain; Cholesterol; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Linkage Disequilibrium; Male; Mexico; Middle Aged; Polymorphism, Single Nucleotide; Risk Factors; Triglycerides

MicroRNAs (miRNAs) are short noncoding RNA species generated by the processing of longer precursors by the ribonucleases Drosha and Dicer. Platelets contain large amounts of miRNA that are altered by disease, in particular diabetes mellitus.. This study determined why platelet miRNA levels are attenuated in diabetic individuals and how decreased levels of the platelet-enriched miRNA, miR-223, affect platelet function.. Dicer levels were altered in platelets from diabetic mice and patients, a change that could be attributed to the cleavage of the enzyme by calpain, resulting in loss of function. Diabetes mellitus in human subjects as well as in mice resulted in decreased levels of platelet miR-142, miR-143, miR-155, and miR-223. Focusing on only 1 of these miRNAs, miR-223 deletion in mice resulted in modestly enhanced platelet aggregation, the formation of large thrombi and delayed clot retraction compared with wild-type littermates. A similar dysregulation was detected in platelets from diabetic patients. Proteomic analysis of platelets from miR-223 knockout mice revealed increased levels of several proteins, including kindlin-3 and coagulation factor XIII-A. Whereas, kindlin-3 was indirectly regulated by miR-223, factor XIII was a direct target and both proteins were also altered in diabetic platelets. Treating diabetic mice with a calpain inhibitor prevented loss of platelet dicer as well as the diabetes mellitus-induced decrease in platelet miRNA levels and the upregulation of miR-223 target proteins.. Thus, calpain inhibition may be one means of normalizing platelet miRNA processing as well as platelet function in diabetes mellitus.

Topics: Adult; Animals; Blood Platelets; Calcium; Calpain; Cytoskeletal Proteins; DEAD-box RNA Helicases; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Factor XIII; Female; Humans; Ionomycin; Male; Membrane Proteins; Mice; Mice, Inbred C57BL; Mice, Knockout; MicroRNAs; Microsatellite Repeats; Middle Aged; Neoplasm Proteins; Platelet Aggregation; Proteome; Ribonuclease III

Topics: Animals; Blood Platelets; Calpain; DEAD-box RNA Helicases; Diabetes Mellitus, Type 2; Female; Humans; Male; MicroRNAs; Platelet Aggregation; Ribonuclease III

We attempted to validate earlier findings on the nature of the association of the IRS1, CAPN10, and PPARG genes with type 2 diabetes mellitus (T2DM) in the high-risk population of Hyderabad, India.. A sample of 1379 subjects (758 T2DM patients, 621 controls) was genotyped for single nucleotide polymorphisms (SNPs) of the IRS1 (rs1801278), CAPN10 (rs3792267, rs5030952), and PPARG (rs1801282) genes.. The allele and genotype frequencies of IRS1 (rs1801278) and CAPN10 (rs3792267) SNPs differed significantly between the patient and control groups. Logistic regression analysis suggested a significant association of these two SNPs (P ≤ 0.007) with T2DM and the strength of association did not alter when adjusted for age, gender, body mass index, and the waist : hip ratio as covariates. The same two SNPs showed significant association in multivariate logistic regression analyses, even after Bonferroni correction for multiple testing, suggesting an independent nature of the role of these genes in the manifestation of T2DM in our population.. We replicated the significant association of rs1801278 and rs3792267 SNPs of the IRS1 and CAPN10 genes with T2DM in the population of Hyderabad. Despite the known biological significance of the PPARG gene and a sufficient statistical power of the present study, we could not replicate the association of PPARG with T2DM in our high-risk population. Given the vast ethnic, geographic, and genetic heterogeneity of the Indian population, many more studies are needed covering the ethnic and geographic heterogeneity of India to enable identification of an Indian-specific profile of genes associated with T2DM.

Topics: Alleles; Body Mass Index; Calpain; Diabetes Mellitus, Type 2; Gene Frequency; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; India; Insulin Receptor Substrate Proteins; Polymorphism, Single Nucleotide; PPAR gamma

Calpain-10 is a ubiquitously expressed protease that serves as an intracellular calcium-dependent cysteine protease and is regarded to be one of the candidate genes for type 2 diabetes mellitus (T2DM). We aimed to identify the association of the common variants of this gene and the risk of T2DM in the Kurdish ethnic group of Iran.. Study groups included 173 T2DM and 173 normoglycemic subjects. Genotyping was determined by PCR-RFLP. Genotypic and allelic frequencies were then evaluated. Data was analyzed using SPSS software.. The allelic frequency of the A-allele of SNP-43 variant was significantly different (p = 0.01) between case and control groups (18% vs. 11%). The genotype frequencies for SNP-43 did not show any significant difference between case and control individuals. However, the dominant model of SNP-43 was found to be significantly associated with T2DM (OR = 1.75, 95% CI = 1.06 - 2.89, p < 0.029). The distribution and allele frequency of other SNPs (SNP-19 and -63) did not show any significant difference between the study groups. For SNP-43, fasting serum insulin (p = 0.043) and HOMA-IR (p = 0.026) were higher in the control subjects with the GA+AA genotype when compared with the GG genotype. Among the T2DM subjects, there was no significant difference in any of the clinical or biochemical parameters between the GG and GA+AA genotypes of SNP-43. Normoglycemic subjects carrying the 2R/3R+3R/3R genotypes of SNP-19 had significantly lower HDL-C (p = 0.034) as compared with those with the 2R/2R genotype. In T2DM subjects, no significant difference was found in any of the clinical or biochemical parameters between 2R/2R and 2R/3R+3R/3R genotypes. T2DM subjects carrying the CT+TT genotypes of SNP-63 variation had significantly higher LDL-C (p = 0.015) as compared with those with the CC genotype. In normoglycemic subjects, no significant difference was found in any of the clinical or biochemical parameters between CC and CT+TT genotypes.. Our findings revealed that there is an association between the SNP-43, but not SNP-19 and -63, and T2DM in the Kurdish ethnic group of West Iran.

Topics: Adult; Aged; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genetic Variation; Humans; Iran; Male; Middle Aged

The variations in the Calpain-10 gene have been suggested to be related to susceptibility to type 2 diabetes mellitus (T2DM) in different populations. In this study, we investigated the relationship between single nucleotide polymorphism (SNP)-19, -44 and -63 in the Calpain-10 gene and the development of T2DM in a Turkish population.. A total of 211 subjects were recruited: 118 patients with a diagnosis of T2DM and 93 unrelated healthy subjects.. There were no significant differences in the genotype and allele distribution of SNPs studied between the patients with T2DM and controls (p > 0.05), whereas the frequencies of 121 haplotype and 122/121 haplotype combination were found to be higher in patients with T2DM than in controls (p < 0.05). No association was observed between the variations in the Calpain-10 gene and glycaemic control and lipid parameters (p > 0.05). The SNP-19 insertion/insertion was significantly related to increased body mass index (BMI) in male diabetic patients (p < 0.05).. The present study indicates that 121 haplotype and 122/121 haplotype combination of SNP-19, -44 and -63 in the Calpain-10 gene are associated with the development of T2DM in Turkish patients.

Topics: Adult; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Male; Middle Aged; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Turkey

Dyslipidemia is a major public health problem, and therefore, it is important to develop dietary strategies to diminish the prevalence of this disorder. It was recently reported that diet may play an important role in triggering insulin resistance by interacting with genetic variants at the CAPN10 gene locus in patients with metabolic syndrome. Nonetheless, it remains unknown whether genetic variants of genes involved in the development of type 2 diabetes are associated with variations in high-density lipoprotein cholesterol (HDL-C). The study used a single-center, prospective, cohort design. Here, we assessed the effect of four variants of the CAPN10 gene on HDL-C levels in response to a soy protein and soluble fiber dietary portfolio in subjects with dyslipidemia. In 31 Mexican dyslipidemic individuals, we analyzed four CAPN10 gene variants (rs5030952, rs2975762, rs3792267, and rs2975760) associated with type 2 diabetes. Subjects with the GG genotype of the rs2975762 variant of the CAPN10 gene were better responders to dietary intervention, showing increased HDL-C concentrations from the first month of treatment. HDL-C concentrations in participants with the wild type genotype increased by 17.0%, whereas the HDL-C concentration in subjects with the variant genotypes increased by only 3.22% (p = 0.03); the low-density lipoprotein cholesterol levels of GG carriers tended to decrease (-12.6%). These results indicate that Mexican dyslipidemic carriers of the rs2975762-GG genotype are better responders to this dietary intervention.

Topics: Adult; Calpain; Cholesterol, HDL; Diabetes Mellitus, Type 2; Dietary Fiber; Dyslipidemias; Female; Genetic Variation; Genotype; Humans; Male; Mexico; Prospective Studies; Soybean Proteins

Diabetes Mellitus (DM) type 2 is a common pathology with multifactorial etiology, which exact genetic bases remain unknown. Some studies suggest that single nucleotides polymorphisms (SNPs) in the CAPN10 gene (Locus 2q37.3) could be associated with the development of this disease, including the insertion/deletion polymorphism SNP-19 (2R→3R).. The present study determined the association between the SNP-19 and the risk of developing DM type 2 in Ciudad Juarez population.. For this study 107 participants were selected: 43 diabetics type 2 (cases) and 64 non diabetics with no family history of DM type 2 in first grade (control). Anthropometric studies were realized as well as lipids, lipoproteins and serum glucose biochemical profiles. The genotypification of SNP-19 was performed using peripheral blood lymphocytes DNA, polymerase chain reactions (PCR), and electrophoretic analysis in agarose gels. Once obtained the genotypic and allelic frequencies, the Hardy-Weinberg equilibrium test (GenAlEx 6.4) was also performed.. Using the X² analysis it was identified the genotypic differences between cases and control with higher frequency of the homozygous genotype 3R of SNP- 19 in the cases group (0.418) compared to control group (0.265). Also, it was observed an association between genotype 2R/3R with elevated weight, body mass index, and waist and hip circumferences, but only in the diabetic group (P=< 0.05).. The findings in this study suggest that SNP-19 in CAPN10 may participate in the development of DM type 2 in the studied population.. Introducción: La diabetes mellitus (DM) tipo 2 es una patología común de origen multifactorial cuyas bases genéticas exactas se desconocen aún; diversos estudios sugieren que los polimorfismos de nucleótido único (SNPs) en el gen CAPN10 (Locus 2q37.3) podrían participar en su desarrollo, incluyendo el polimorfismo de inserción/ deleción SNP-19 (2R→3R). Objetivo: Determinar la relación entre el polimorfismo SNP-19 y la presencia de DM tipo 2 en una población de Ciudad Juárez. Métodos: Se seleccionaron 107 individuos: 43 diabéticos tipo 2 (casos) y 64 no diabéticos sin antecedentes heredo-familiares de DM tipo 2 en primer grado (control). Se realizó estudio antropométrico y perfil bioquímico de lípidos, lipoproteínas y glucosa sérica. Se extrajo ADN de linfocitos de sangre periférica y se amplificó mediante la técnica de reacción en cadena de la polimerasa (PCR). Se analizaron los genotipos del polimorfismo SNP-19 del gen CAPN10 por análisis electroforético en geles de agarosa. Se calcularon las frecuencias genotípicas y alélicas y se realizaron pruebas de equilibrio de Hardy-Weinberg (GenAlEx 6.4). Resultados: El análisis mediante la prueba X² identificó diferencias en los genotipos entre casos y control, con una mayor frecuencia del genotipo homocigoto 3R del SNP-19 en el grupo de casos (0.418) respecto al grupo control (0.265). El genotipo 2R/3R presentó relación con valores elevados de peso, índice de masa corporal y perímetros de cintura y cadera; pero solo en el grupo de diabéticos (P=< 0.05). Conclusión: Los resultados de esta investigación sugieren la participación del SNP-19 del gen CAPN10 en el desarrollo de DM tipo 2 en la población estudiada.

Topics: Adult; Aged; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genotype; Humans; Male; Mexico; Middle Aged; Polymorphism, Single Nucleotide

Dysfunction of β-cells is a major characteristic in the pathogenesis of type 2 diabetes mellitus (T2DM). The combination of obesity and T2DM is associated with elevated plasma free fatty acids (FFAs). However, molecular mechanisms linking FFAs to β-cell dysfunction remain poorly understood. In the present study, we identified that the major endoplasmic reticulum stress (ERS) marker, Grp78 and ERS-induced apoptotic factor, CHOP, were time-dependently increased by exposure of β-TC3 cells to FFA. The expression of ATF6 and the phosphorylation levels of PERK and IRE1, which trigger ERS signaling, markedly increased after FFA treatments. FFA treatments increased cell apoptosis by inducing ERS in β-TC3 cells. We also found that FFA-induced ERS was mediated by the store-operated Ca(2+) entry through promoting the association of STIM1 and Orai1. Moreover, calpain-2 was required for FFA-induced expression of CHOP and activation of caspase-12 and caspase-3, thus promoting cell apoptosis in β-TC3 cells. Together, these results reveal pivotal roles for Ca(2+)/calpain-2 pathways in modulating FFA-induced β-TC3 cell ERS and apoptosis.

Topics: Activating Transcription Factor 6; Analysis of Variance; Animals; Apoptosis; Blotting, Western; Calcium; Calpain; Diabetes Mellitus, Type 2; DNA Primers; eIF-2 Kinase; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Fatty Acids, Nonesterified; Gene Silencing; Heat-Shock Proteins; Immunoprecipitation; Insulin-Secreting Cells; Membrane Proteins; Mice; Phosphorylation; Protein Serine-Threonine Kinases; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Transcription Factor CHOP

Type 2 diabetes mellitus is increasing dramatically in sub-Saharan Africa, and genetic predisposition is likely involved in that. Yet, genetic variants known to confer increased susceptibility among Caucasians are far from being established in African populations. In Ghanaian adults, we examined associations of several of these polymorphisms with type 2 diabetes.. A hospital-based case-control study on type 2 diabetes (and hypertension) was conducted in Kumasi, Ghana. TCF7L2 rs7903146, KCNJ11 rs5219, PPARγ rs1801282 and CAPN10 rs3842570, rs3792267, and rs5030952 were typed and associations with type 2 diabetes and phenotypic traits examined.. 675 patients with type 2 diabetes and 377 controls were compared. The minor allele frequency of the TCF7L2 (T) allele was 0.33. In the multivariate model, this allele increased the risk of type 2 diabetes by 39% (95% confidence interval (CI), 1.07-1.81; p = 0.014). The minor alleles KCNJ11 (G) and PPARγ (G) were practically absent (each, 0.001). Minor allele frequencies of CAPN10 were for -43 (A) 0.11 and for -63 (C) 0.46. These variants showed no significant associations with type 2 diabetes. Two CAPN10 haplotypes tended to protect against type 2 diabetes: 211 (aOR, 0.32; 95% CI, 0.03-1.92; p = 0.31) and 221 (aOR, 0.73; 95% CI, 0.48-1.10; p = 0.13).. In urban Ghana, the frequency of the TCF7L2 rs7903146 (T) allele is comparable to the one in Caucasians; the association with type 2 diabetes is slightly weaker. The risk allele KCNJ11 (G) and the protective allele PPARγ (G) are virtually absent. The potential influence of comparatively rare CAPN10 haplotypes on type 2 diabetes risk in this population requires further evaluation. Large-scale genetic studies among native Africans aiming at fine-mapping the candidate genes are needed to identify the actual factors involved in their increased susceptibility to type 2 diabetes.

Topics: Adult; Aged; Alleles; Black People; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genotype; Ghana; Haplotypes; Hospitals; Humans; Male; Middle Aged; Odds Ratio; Polymorphism, Single Nucleotide; Potassium Channels, Inwardly Rectifying; PPAR gamma; Transcription Factor 7-Like 2 Protein

The incidence of type 2 diabetes mellitus (T2DM) is increasing worldwide and diverse environmental and genetic risk factors are well recognized. Single nucleotide polymorphisms (SNPs) in the calpain-10 gene (CAPN-10), which encodes a protein involved in the secretion and action of insulin, and chronic exposure to inorganic arsenic (iAs) through drinking water have been independently associated with an increase in the risk for T2DM. In the present work we evaluated if CAPN-10 SNPs and iAs exposure jointly contribute to the outcome of T2DM. Insulin secretion (beta-cell function) and insulin sensitivity were evaluated indirectly through validated indexes (HOMA2) in subjects with and without T2DM who have been exposed to a gradient of iAs in their drinking water in northern Mexico. The results were analyzed taking into account the presence of the risk factor SNPs SNP-43 and -44 in CAPN-10. Subjects with T2DM had significantly lower beta-cell function and insulin sensitivity. An inverse association was found between beta-cell function and iAs exposure, the association being more pronounced in subjects with T2DM. Subjects without T2DM who were carriers of the at-risk genotype SNP-43 or -44, also had significantly lower beta-cell function. The association of SNP-43 with beta-cell function was dependent on iAs exposure, age, gender and BMI, whereas the association with SNP-44 was independent of all of these factors. Chronic exposure to iAs seems to be a risk factor for T2DM in humans through the reduction of beta-cell function, with an enhanced effect seen in the presence of the at-risk genotype of SNP-43 in CAPN-10. Carriers of CAPN-10 SNP-44 have also shown reduced beta-cell function.

Topics: Adult; Aged; Arsenic; Calpain; Diabetes Mellitus, Type 2; Environmental Exposure; Environmental Pollutants; Female; Genotype; Humans; Insulin; Insulin Resistance; Insulin Secretion; Insulin-Secreting Cells; Male; Middle Aged; Pilot Projects; Polymorphism, Single Nucleotide; Risk Factors

Platelets from patients with diabetes are hyperreactive and demonstrate increased adhesiveness, aggregation, degranulation, and thrombus formation, processes that contribute to the accelerated development of vascular disease. Part of the problem seems to be dysregulated platelet Ca(2+) signaling and the activation of calpains, which are Ca(2+)-activated proteases that result in the limited proteolysis of substrate proteins and subsequent alterations in signaling. In the present study, we report that the activation of μ- and m-calpain in patients with type 2 diabetes has profound effects on the platelet proteome and have identified septin-5 and the integrin-linked kinase (ILK) as novel calpain substrates. The calpain-dependent cleavage of septin-5 disturbed its association with syntaxin-4 and promoted the secretion of α-granule contents, including TGF-β and CCL5. Calpain was also released by platelets and cleaved CCL5 to generate a variant with enhanced activity. Calpain activation also disrupted the ILK-PINCH-Parvin complex and altered platelet adhesion and spreading. In diabetic mice, calpain inhibition reversed the effects of diabetes on platelet protein cleavage, decreased circulating CCL5 levels, reduced platelet-leukocyte aggregate formation, and improved platelet function. The results of the present study indicate that diabetes-induced platelet dysfunction is mediated largely by calpain activation and suggest that calpain inhibition may be an effective way of preserving platelet function and eventually decelerating atherothrombosis development.

Topics: Adult; Aged; Animals; Blood Platelets; Blood Proteins; Calcium Signaling; Calpain; Case-Control Studies; Cell Cycle Proteins; Chemokine CCL5; Diabetes Mellitus, Type 2; Female; Humans; Hypoglycemic Agents; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Middle Aged; Pioglitazone; Platelet Activation; Protein Serine-Threonine Kinases; Proteomics; Septins; Thiazolidinediones

Copy number variations (CNVs) have been shown to be associated with several diseases. They can cause deviation of genotypes from Hardy-Weinberg Equilibrium (HWE). Genetic case-control association studies in Thais revealed that genotype distribution of CAPN10 Indel19 was deviated from HWE after correction of genotyping error. Therefore, we aim to identify CNVs within CAPN10 Indel19 region. The semi-quantitative denaturating high performance liquid chromatography (DHPLC) method was used to detect CNVs in the region of CAPN10 Indel19 marker in cohort of 305 patients with type 2 diabetes and 250 control subjects without diabetes. CNVs in the region of CAPN10 Indel19 was successfully detected by DHPLC. After correction of genotype calling based on the status of identified CNVs, CAPN10 Indel19 genotypes were well-fitted for HWE (p>0.05). However, we did not find association between CNV genotypes and risk of type 2 diabetes in our population. CNVs in CAPN10 have been identified in Thais. These CNVs lead to deviation from HWE of CAPN10 Indel19 genotypes. After excluding identified CNVs from the analysis, CAPN10 Indel19 was associated with type 2 diabetes. The information obtained from our study would be helpful for genotyping accuracies of SNPs residing in the CNVs region.

Topics: Adult; Aged; Calpain; Case-Control Studies; Chromatography, High Pressure Liquid; Cohort Studies; Diabetes Mellitus, Type 2; DNA Copy Number Variations; Female; Gene Dosage; Genetic Markers; Genotype; Humans; Male; Middle Aged; Multiplex Polymerase Chain Reaction; Reproducibility of Results

The aim was to investigate the association between the CAPN10 gene single nucleotide polymorphisms (SNPs) -44 (rs2975760), -43 (rs3792267), -19 (rs3842570), and -63 (rs5030952) and type 2 diabetes mellitus in an Asian Indian population in Southern India. A total of 1443 subjects, 794 normal glucose tolerant (NGT) and 649 type 2 diabetes mellitus subjects, were randomly selected from the Chennai Urban Rural Epidemiology Study. These subjects were genotyped for the 4 CAPN10 SNPs using polymerase chain reaction-restriction fragment length polymorphism and validated by direct sequencing. None of the 4 SNPs showed any significant differences in the genotypic distribution among the NGT and type 2 diabetes mellitus subjects (P = .20, .86, .34, and .39 for SNPs -44, -43, -19, and -63, respectively). The NGT subjects with the 11 genotype of the SNP -63 had significantly higher 2-hour postload plasma glucose (mean ± SD, 5.66 ± 1.05 mmol/L) levels compared with the combined 12 and 22 genotype group (5.33 ± 1.11 mmol/L, P = .004). The P value remained significant even after adjusting for age, sex, body mass index, smoking, and alcohol consumption (nominal P = .008). No significant difference in the biochemical parameters was observed when the subjects were stratified according to the other SNPs. The 2111 haplotype corresponding to SNPs -44, -43, -19, and -63 showed a significant difference in the proportion among NGT (0.18) and type 2 diabetes mellitus subjects (0.22, nominal P = .014). Although the Bonferroni correction based on the asymptotic test does not preserve this significance, the test based on the empirical distribution remained significant. In conclusion, our study raises the possibility that the 2111 haplotype of SNPs -44, -43, -19, and -63 may be associated with type 2 diabetes mellitus, although none of these SNPs may be individually associated with diabetes.

Topics: Adult; Alcohol Drinking; Base Sequence; Body Mass Index; Calpain; Cholesterol; Cholesterol, LDL; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Haplotypes; Humans; India; Male; Middle Aged; Molecular Sequence Data; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Smoking; Triglycerides; Waist Circumference

Brain glucose metabolism is impaired in Alzheimer's disease (AD), the most common form of dementia. Type 2 diabetes mellitus (T2DM) is reported to increase the risk for dementia, including AD, but the underlying mechanism is not understood. Here, we investigated the brain insulin-PI3K-AKT signalling pathway in the autopsied frontal cortices from nine AD, 10 T2DM, eight T2DM-AD and seven control cases. We found decreases in the levels and activities of several components of the insulin-PI3K-AKT signalling pathway in AD and T2DM cases. The deficiency of insulin-PI3K-AKT signalling was more severe in individuals with both T2DM and AD (T2DM-AD). This decrease in insulin-PI3K-AKT signalling could lead to activation of glycogen synthase kinase-3β, the major tau kinase. The levels and the activation of the insulin-PI3K-AKT signalling components correlated negatively with the level of tau phosphorylation and positively with protein O-GlcNAcylation, suggesting that impaired insulin-PI3K-AKT signalling might contribute to neurodegeneration in AD through down-regulation of O-GlcNAcylation and the consequent promotion of abnormal tau hyperphosphorylation and neurodegeneration. The decrease in brain insulin-PI3K-AKT signalling also correlated with the activation of calpain I in the brain, suggesting that the decrease might be caused by calpain over-activation. Our findings provide novel insight into the molecular mechanism by which type 2 diabetes mellitus increases the risk for developing cognitive impairment and dementia in Alzheimer's disease.

Topics: Acylation; Aged; Aged, 80 and over; Alzheimer Disease; Arrestins; beta-Arrestins; beta-N-Acetylhexosaminidases; Brain; Calpain; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Male; Phosphorylation; Signal Transduction; tau Proteins

Type 2 diabetes (T2D) is a chronic degenerative disease that involves the participation of several genetic and environmental factors. The objective of the study was to determine the association of the IRS1 (rs1801278), CAPN10 (rs3792267), TCF7L2 (rs7903146 and rs12255372), and PPARG (rs1801282) gene polymorphisms with T2D, in two different Mexican populations. We conducted a case-control replication study in the state of Guerrero and in Mexico City, with 400 subjects from Guerrero and 1065 from Mexico City. Data were analyzed by logistic regression, adjusting by ancestry, age, gender, and BMI, to determine the association with T2D. Heterozygosity for the Gly972Arg variant of the IRS1 gene showed the strongest association for T2D in both analyzed samples (OR = 2.43, 95% CI 1.12-5.26 and 2.64, 95% CI 1.37-5.10, respectively). In addition, an association of two SNPs of the TCF7L2 gene with T2D was observed in both cities: rs7903146, (for Guerrero OR = 1.98 CI95% 1.02-3.89 and for Mexico OR = 1.94 CI95% 1.31-2.88) and rs12255372 (OR = 1.79 CI95% 1.08-2.97, OR = 1.78 CI95% 1.17-2.71 respectively). We suggest that our results provide strong evidence that variation in the IRS1 and TCF7L2 genes confers susceptibility to T2D in our studied populations.

Topics: Adult; Aged; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Humans; Insulin Receptor Substrate Proteins; Male; Mexico; Middle Aged; Polymorphism, Single Nucleotide; PPAR gamma; Transcription Factor 7-Like 2 Protein

New-onset, posttransplant diabetes mellitus (PTDM) has a high incidence after kidney transplantation in patients medicated with tacrolimus, and may adversely affect the patient and graft survival. The pathophysiology of PTDM closely mimics that of type II diabetes mellitus (T2DM). One of possible genetic factors predisposing to PTDM might be polymorphism in calpain-10 gene (CAPN10), previously associated with increased risk of T2DM in general population. Therefore, the present study was aimed at evaluation of CAPN10 gene polymorphisms in PTDM in kidney transplant patients medicated with tacrolimus. A total of 214 nondiabetic kidney transplant patients medicated with tacrolimus (56 patients with PTDM and 158 patients without PTDM were genotyped for the presence of CAPN10 gene variants (SNP-43: rs3792267:G>A, SNP-19: rs3842570 ins/del and SNP-63: rs5030952:C>T) using PCR-based assays. Frequency of SNP-63 minor allele was slightly increased in PTDM patients (P=0.056), and an association of SNP-63 heterozygosity and the risk of PTDM (odds ratios (OR)=2.45, P=0.023) was observed. An increased odds for PTDM development in patients carrying 1-1-2 haplotype (rs3792267:G-rs3842570:ins-rs5030952:T) compared to noncarriers was also noted (OR=2.35, P=0.026). Patients' higher body mass index and SNP-63 minor T allele carrier status were identified as independent PTDM risk factors, confirmed by multivariate regression analysis. This is the first study of CAPN10 polymorphism in relation to PTDM risk. However, the application of SNP-63 (rs5030952:C>T) as a marker of PTDM should be verified by further independent studies.

Topics: Adult; Body Mass Index; Calpain; Diabetes Mellitus, Type 2; Female; Humans; Kidney Transplantation; Male; Middle Aged; Polymorphism, Single Nucleotide; Risk Factors; Tacrolimus

The islet in type 2 diabetes (T2DM) and the brain in neurodegenerative diseases share progressive cell dysfunction, increased apoptosis, and accumulation of locally expressed amyloidogenic proteins (islet amyloid polypeptide (IAPP) in T2DM). Excessive activation of the Ca(2+)-sensitive protease calpain-2 has been implicated as a mediator of oligomer-induced cell death and dysfunction in neurodegenerative diseases. To establish if human IAPP toxicity is mediated by a comparable mechanism, we overexpressed human IAPP in rat insulinoma cells and freshly isolated human islets. Pancreas was also obtained at autopsy from humans with T2DM and nondiabetic controls. We report that overexpression of human IAPP leads to the formation of toxic oligomers and increases beta cell apoptosis mediated by increased cytosolic Ca(2+) and hyperactivation of calpain-2. Cleavage of alpha-spectrin, a marker of calpain hyperactivation, is increased in beta cells in T2DM. We conclude that overactivation of Ca(2+)-calpain pathways contributes to beta cell dysfunction and apoptosis in T2DM.

Topics: Adult; Aged; Aged, 80 and over; Amyloid; Animals; Apoptosis; Calcium; Calpain; Cell Line, Tumor; Cell Survival; Cytosol; Diabetes Mellitus, Type 2; Dipeptides; Enzyme Activation; Female; Humans; Insulin-Secreting Cells; Islet Amyloid Polypeptide; Male; Middle Aged; Protein Transport; Rats; Recombinant Fusion Proteins; Spectrin

Calpain 10 (CAPN10) gene may contribute to the pathogenesis of type 2 diabetes mellitus (T2DM).. To examine the contribution of four CAPN10 gene variants to T2DM risk in an Irish sample.. Genotyping of marker 19 insertion-deletion (ins/del) and three CAPN10 variants, rs3792267, rs3749166 and rs5030952 at the CAPN10 gene was performed in 236 T2DM subjects and 120 controls. Allelic, genotypic and haplotype comparisons were conducted between the groups.. In the examined markers, no significant differences were observed although the deletion/deletion allele tended to be more common in T2DM subjects (chi(2) = 3.2, P = 0.07). A significant overrepresentation of a haplotype comprising (rs3792267), (19) and rs3749166 (chi(2) = 5.3, P = 0.021) was seen in T2DM subjects. Two protective haplotypes were detected: (G-ins-G) of (rs3792267), (19) and rs3749166 (chi(2) = 6.7, P = 0.009) and (ins-G-C) of (19), (rs3749166) and rs5030952 (chi(2) = 8.5, P = 0.003).. CAPN10 gene variants may affect T2DM susceptibility in the Irish population.

Topics: Alleles; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Gene Deletion; Gene Frequency; Genetic Markers; Genetic Variation; Genotype; Haplotypes; Humans; Ireland; Linkage Disequilibrium; Male; Middle Aged; Odds Ratio; Polymorphism, Genetic

There is a known inverse association between type 2 diabetes (T2D) and prostate cancer (PrCa) that is poorly understood. Genetic studies of the T2D-PrCa association may provide insight into the underlying mechanisms of this association. We evaluated associations in the Atherosclerosis Risk in Communities study between PrCa and nine T2D single nucleotide polymorphisms from genome-wide association studies of T2D (in CDKAL1, CDKN2A/B, FTO, HHEX, IGF2BP2, KCNJ11, PPARG, SLC30A8, and TCF7L2) and four T2D single nucleotide polymorphisms from pre-genome-wide association studies (in ADRB2, CAPN10, SLC2A2, and UCP2). From 1987 to 2000, there were 397 incident PrCa cases among 6,642 men ages 45 to 64 years at baseline. We used race-adjusted Cox proportional hazards models to estimate associations between PrCa and increasing number of T2D risk-raising alleles. PrCa was positively associated with the CAPN10 rs3792267 G allele [hazard ratio (HR) 1.20; 95% confidence interval (CI), 1.00-1.44] and inversely associated with the SLC2A2 rs5400 Thr110 allele (HR, 0.85; 95% CI, 0.72, 1.00), the UCP2 rs660339 Val55 allele (HR, 0.84; 95% CI, 0.73, 0.97) and the IGF2BP2 rs4402960 T allele (HR, 0.79; 95% CI, 0.61-1.02; blacks only). The TCF7L2 rs7903146 T allele was inversely associated with PrCa using a dominant genetic model (HR, 0.79; 95% CI, 0.65-0.97). Further knowledge of T2D gene-PrCa mechanisms may improve understanding of PrCa etiology.

Topics: Atherosclerosis; Calpain; Cohort Studies; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genome-Wide Association Study; Glucose Transporter Type 2; Humans; Ion Channels; Male; Middle Aged; Mitochondrial Proteins; Polymorphism, Single Nucleotide; Proportional Hazards Models; Prostatic Neoplasms; RNA-Binding Proteins; TCF Transcription Factors; Transcription Factor 7-Like 2 Protein; Uncoupling Protein 2

The objective of this study was to test the association between calpain-10 (CAPN10), a diabetes susceptibility gene, with risk of pancreatic cancer (PC).. DNA samples from 83 incident exocrine PC cases and 166 controls, all of whom were smokers, were genotyped for four markers of CAPN10 in a nested case-control study based on the Beta-Carotene and Retinol Efficacy Trial (CARET), a randomized chemoprevention trial of subjects at high risk of lung cancer. Controls were matched on sex, race, age, CARET intervention arm, duration of exposure to asbestos, and smoking history. Conditional logistic regression was used for statistical analyses.. The minor allele of SNP-43 (rs3792267) in intron 3 was associated with increased risk of PC with an odds ratio of 1.57 (95%CI 1.03-2.38, p = 0.035) per allele. The three markers of the highest risk haplotype had an odds ratio of 1.98 (95%CI 1.12-3.49, p = 0.019) for risk of PC compared to the most common haplotype. There was no evidence of interaction between either of these associations by diabetes status.. These results suggest that variation in CAPN10 may be associated with increased risk of PC among smokers. Thus, studies of genes associated with diabetes risk in PC are warranted in a larger population.

Topics: Aged; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genotype; Humans; Male; Middle Aged; Pancreatic Neoplasms; Polymorphism, Single Nucleotide; Reverse Transcriptase Polymerase Chain Reaction; Smoking

Linkage and association studies have detected a role for Calpain-10 (CAPN10) polymorphisms in susceptibility to T2DM in many populations. This study aimed to evaluate possible associations between three SNPs in the CAPN10 (UCSNPs -43, -19 and -63) gene and T2DM in the east Indian population. The distribution of genotype frequency of UCSNP-63 varied significantly between T2DM patients and controls under a dominant model. The uncommon (T) allele (OR = 3.74, 95% CI: 1.44-9.7) of the UCSNP-63 and haplotype 112 (OR = 3.4, 95% CI: 1.17-9.9) were associated with increased risk of T2DM. On the contrary, the most common haplotype 121 (OR = 0.70 95% CI: 0.50-0.99) was associated with a reduced risk for T2DM. In our population a novel 111/112-haplotype combination created by the CAPN10 UCSNP-43, -19 and -63 was associated with risk of T2DM. Haplotypes 112 and 121 with opposite genetic influences also co-exist in our population.

Topics: Calpain; Diabetes Mellitus, Type 2; Female; Genetic Linkage; Genetic Predisposition to Disease; Haplotypes; Humans; India; Male; Polymorphism, Single Nucleotide; Prevalence; Risk Factors

Genetic variations in the calpain-10 gene (CAPN10), in particular the at-risk diplotype (112/121), were previously implicated with increased risk of type 2 diabetes (T2D).. We examined the association of CAPN10 UCSNP-43 (rs3792267), UCSNP-19 (rs3842570), and UCSNP-63 (rs5030952) SNPs with T2D in 917 Tunisian T2D patients and 748 non-diabetic controls. CAPN10 genotyping was done by PCR-RFLP.. Enrichment of UCSNP-19 2R (minor) allele and 2R/2R genotype was found in T2D patients; the allele and genotype distribution of UCSNP-43 and UCSNP-63 alleles and genotypes were not significantly different between patient groups and non-diabetic control subjects. Regression analysis demonstrated progressive increases in T2D risk in 3R/2R [OR (95% CI) = 1.35 (1.08 - 1.68)] and 2R/2R [OR (95% CI) = 1.61 (1.20 - 2.18)] genotypes. Of the six haplotypes detected, enrichment of haplotype 111 (UCSNP-43/UCSNP-19/UCSNP-63) was seen in patients (Pc = 0.034); the distribution of the other haplotypes was comparable between patients and control subjects; neither haplotype 211 nor haplotype 212 was observed. Furthermore, the frequency of all CAPN10 diplotypes identified, including the "high-risk diplotype (112/121) reported for Mexican-Americans and Northern Europeans, were comparable between patients and controls.. CAPN10 UCSNP-19 variant, and the 111 haplotype contribute to the risk of T2D in Tunisian subjects; no significant associations between CAPN10 diplotypes and T2D were demonstrated for Tunisians.

Topics: Adult; Aged; Aged, 80 and over; Arabs; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Polymorphism, Single Nucleotide; Risk; Tunisia

Common variations in the calpain 10 (CAPN10) gene variants UCSNP-43, UCSNP-19 and UCSNP-63, and the 112/121 diplotype, are associated with an increased risk of type 2 diabetes (T2DM) and T2DM-related traits.. The association of UCSNP-43, -19 and -63 CAPN10 SNPs with T2DM was assessed in 917 Tunisian T2DM patients and 748 ethnically matched non-diabetic controls. CAPN10 genotyping was done by PCR-RFLP.. Significant differences in UCSNP-19 MAF, but not UCSNP-43 or -63, and genotype distribution were seen between patients and controls. Heterogeneity in UCSNP-19, but not UCSNP-43 and -63, genotype distribution was noted according to geographical origin. Obesity was associated with UCSNP-19, while raised fasting glucose was associated with UCSNP-63, and increased HDL was associated with UCSNP-43. Enrichment of homozygous UCSNP-19 2/2 was seen in overweight and obese compared with lean patients; logistic-regression analyses demonstrated a positive association of the 2/2 genotype with overweight [P=0.003; OR (95% CI)=2.07 (1.28-3.33)] and obese [P=0.021; OR (95% CI)=1.83 (1.10-3.07)] patients. Of the six CAPN10 haplotypes identified, significant enrichment of only haplotype 111 was seen in T2DM patients [Pc=0.034; OR (95% CI)=1.22 (1.06-1.41)], while the frequency of all identified CAPN10 diplotypes, including the high-risk 112/121, was comparable between patients and controls.. While CAPN10 UCSNP-19 SNP and haplotype 111 contribute to the risk of T2DM in Tunisian subjects, no significant association between CAPN10 diplotypes and T2DM was demonstrated.

Topics: Aged; Arabs; Blood Glucose; Body Mass Index; Calpain; Cholesterol, HDL; Diabetes Mellitus, Type 2; Fasting; Female; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Male; Middle Aged; Obesity; Overweight; Polymerase Chain Reaction; Polymorphism, Genetic; Polymorphism, Restriction Fragment Length; Tunisia

To examine the role of calpain-10 SNP-44, -43, -63 and del/ins-19 in genetic susceptibility to type 2 diabetes mellitus (T2DM) and associations with triglycerides and total cholesterol in a group of subjects residing in the Gaza Strip.. Ninety-six individuals were examined: 48 T2DM patients and 48 controls. The groups were genotyped for calpain-10 SNP-44, -43, -63, and del/ins-19. Mutagenically separated polymerase chain reaction was used to examine SNP-44; del/ins-19 was examined by electrophoresis of the PCR product on agarose gel, while the restriction fragment length polymorphism method was used for SNP-43 and -63.. There was evidence that the C allele at SNP-44 played a possible role in susceptibility to T2DM (p = 0.01). T2DM patients with G/A genotype were found to have higher levels of total cholesterol in comparison to those homozygous for allele 1 (G/G) in SNP-43. Total cholesterol levels increased in T2DM patients who are homozygous for del/ins-19 allele 2, in T2DM patients with the 121/221 haplotype combination, and in control subjects with the haplotype combination 111/121.. SNP-44 polymorphism of the calpain-10 gene has a significant association with T2DM patients in the Gaza strip. Certain polymorphisms of calpain-10 also have associations with the levels of total cholesterol in both T2DM patients and controls.

Topics: Adult; Aged; Arabs; Calpain; Cholesterol; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genome-Wide Association Study; Haplotypes; Humans; Male; Middle Aged; Middle East; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Triglycerides

In Yucatán, 52% of patients with type 2 diabetes (DT2) present secondary failure to treatment associated with sulphonylurea and metformin. A possible explanation may be due to polymorphisms in the genes IRS1, CAPN10, PPARG2, which are involved in pancreatic beta cell dysfunction and a poor response to the action of insulin. The association of the polymorphisms Gly972Arg, SNP43, and Pro12Ala, of the genes IRS1, CAPN10, PPARG2, with the risk of failure to sulphonylurea and metformin therapies was determinated in patients with DT2 in Yucatán, México. One hundred and thirty and two subjects with DT2 were classified in groups of responders (HbA1c < 8%) and non-responders (HbA1c > 8%) to the treatment, according to the control of hyperglucemia with sulphonylurea and metformin. Demographic, anthropometric and metabolic data were obtained from each subject. The polymorphisms were identified by means of DNA analysis by PCR/RFLP and PCR/OAL. Genotypic and allelic frequencies and the Hardy-Weinberg equilibrium were determined. Statistical analyses consisted of X2 and multiple logistic regression tests (Epi-Info 2000 and SPSS version 12). Obese subjects carrying the genotype AA SNP43 showed 4.69 times more risk of failure to respond to treatment (p = 0.027), when compared with subjects sharing GA genotype: X2 (OR = 4.69, IC: 1.15-20.59) and multiple logistic regression, p = 0.048, (OR = 3.72, IC: 1.009-13.718). The interaction between genotype AA and the BMI > 27 showed also a significant difference (p = 0.009). The findings suggest the fact that polymorphism SNP43 may influence the response to treatment with sulphonylurea and metformin, the expression being dependent on obesity.

Topics: Aged; Anthropometry; Body Mass Index; Calpain; Diabetes Mellitus, Type 2; Drug Resistance; Female; Genotype; Glycated Hemoglobin; Haplotypes; Humans; Hypoglycemic Agents; Insulin Receptor Substrate Proteins; Lipids; Male; Metformin; Mexico; Middle Aged; Obesity; Polymorphism, Single Nucleotide; PPAR gamma; Risk; Sulfonylurea Compounds

An increased prevalence of type 2 diabetes (T2D) in schizophrenia (SCZ) patients has been observed. Exposure to antipsychotics (APs) has been shown to induce metabolic dysregulation in some patients but not all treated patients. We hypothesized that important candidate genes for T2D may increase risk for T2D in African-American patients with SCZ or schizoaffective disorder. The PAARTNERS study comprises African-American families with at least one proband with SCZ or schizoaffective disorder. The current study of PAARTNERS SCZ and schizoaffective disorder cases (N=820) examined single nucleotide polymorphisms (SNPs) within select T2D candidate genes including transcription factor 7-like 2 (TCF7L2), calpain 10 (CAPN10), and ectoenzyme nucleotide pyrophosphatase phosphodiesterase 1 (ENNP1) for association with prevalent T2D. We report the association of TCF7L2 (rs7903146) with T2D under both additive and recessive models for the risk allele T. Specifically, the odds ratio (OR) for having T2D was 1.4 (p=0.03) under an additive model and 2.4 (p=0.004) under a recessive model. We also report a marginally significant TCF7L2 by AP treatment interaction that should be investigated in future studies. CAPN10 (rs3792267) was marginally associated with T2D with OR=1.5 (p=0.08) when considering the model GG vs. AG/AA with risk allele G. ENPP1 (rs1044498) was not associated with T2D. We conclude TCF7L2, a risk factor for T2D in the general population, is also a risk factor for T2D in African-American patients with SCZ or schizoaffective disorder. Research is needed to determine if T2D associated polymorphisms are of interest in the pharmacogenetics and future treatment choices of antipsychotics in African-American patients.

Topics: Adult; Aged; Antipsychotic Agents; Black or African American; Calpain; Diabetes Mellitus, Type 2; Family Health; Female; Genetic Predisposition to Disease; Genetics, Population; Genome-Wide Association Study; Humans; Male; Middle Aged; Odds Ratio; Pharmacogenetics; Phosphoric Diester Hydrolases; Polymorphism, Single Nucleotide; Psychotic Disorders; Pyrophosphatases; Risk Factors; Schizophrenia; TCF Transcription Factors; Transcription Factor 7-Like 2 Protein

Calpain-10 was the first gene to be identified influencing the risk of type 2 diabetes (T2D) by positioning cloning. Studies in beta-cell lines and rodent islets suggest that calpain-10 may act as a regulator of insulin secretion. However, its role in human pancreatic islets remains unclear. The aim of this study was to examine if calpain-10 expression is altered in islets from patients with T2D and if the transcript level correlates with insulin release. We also tested if polymorphisms in the CAPN10 gene are associated with gene expression and insulin secretion in vitro.. Calpain-10 mRNA expression was analysed in human pancreatic islets from 34 non-diabetic and 10 T2D multi-organ donors. CAPN10 SNP-43 and SNP-44 were genotyped and related to gene expression and insulin release in response to glucose, arginine and glibenclamide. The mRNA level of calpain-10 was elevated by 64% in pancreatic islets from patients with T2D compared with non-diabetic donors (P = 0.01). Moreover, the calpain-10 expression correlated positively with arginine-stimulated insulin release in islets from non-diabetic donors (r = 0.45, P = 0.015). However, this correlation was lost in islets from patients with T2D (r = 0.09; P = 0.8). The G/G variant of SNP-43 was associated with reduced insulin release in response to glucose (P

Topics: Arginine; Base Sequence; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; DNA Primers; Glucose; Glyburide; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Pancreatic Neoplasms; Polymorphism, Single Nucleotide; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

The association of the gene encoding calpain 10 with type 2 diabetes mellitus (T2DM) has been reported. In this study we aimed to evaluate the association of SNP-19,-44, and -63 polymorphisms of calpain 10 with type 2 diabetes and diabetic-related conditions, such as diabetic retinopathy, nephropathy, and neuropathy in a Turkish population. The study group included 202 patients (133 female and 69 male) with T2DM, while the control group included 80 nondiabetic people (44 female and 36 male). Genotyping was done by the polymerase chain reaction and restriction fragment length polymorphism method. Calpain 10 SNP-44 TC genotype was found to be significantly frequent in type 2 diabetic patients with respect to the control group (p < 0.01). Body mass index (BMI) was found to be significantly high in TC genotype with type 2 diabetic patients (p < 0.05). SNP-44 T allele frequency was found to be lower in type 2 diabetic patients compared with the controls (p < 0.01). We conclude that the calpain 10 SNP-44 gene polymorphism may be accepted as a risk factor in the development of T2DM and elevated BMI in type 2 diabetic patients in a Turkish population.

Topics: Alleles; Calpain; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Male; Middle Aged; Polymerase Chain Reaction; Polymorphism, Genetic; Polymorphism, Restriction Fragment Length; Risk Factors; Turkey

To investigate the relationship between single nucleotide polymorphism-56 (SNP-56) in calpain-10 (CAPN-10) gene and polycystic ovary syndrome (PCOS) in Chinese.. The genotypes of SNP-56 of CAPN-10 were determined through polymerase chain reaction Tm-shift genotyping method in 638 local women in Shandong Province. Among them, 334 were patients with PCOS (PCOS group) and 304 were normal women (control group). The baseline parameters including levels of serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), estradiol (E2), testosterone (T) and lipid,as well as the body mass index (BMI) and waist/hip ratio (WHR) were measured. Glucose tolerance and insulin releasing before and after loading with 75 g of glucose were also assayed.. (1) The frequencies of two allelotypes or three genotypes did not differ between PCOS women and normal women (P > 0.05). (2) In PCOS group, patients with AA genotype had a significantly higher plasma glucose of 180 minutes OGTT (5.7 +/- 2. 2)mmol/L [P < 0.01 compared to GA genotype (4.9 +/- 1.2) mmol/L, P < 0.01 compared to GG genotype (4.9 +/- 1.4) mmol/L] and serum total cholesterol (TC) level (4.9 +/- 1.0) mmol/L [P < 0.05 compared to GA genotype (4.5 +/- 0.9) mmol/L]. (3) Compared to PCOS patients with GA + GG genotype (P < 0.05, P < 0.01) or GG genotype (P < 0.05, P < 0.01), there was significantly higher attack rate of diabetes and tumor in the family history of patients with AA genotype.. These findings suggest that CAPN-10 gene SNP-56 which may not contribute to the genetic susceptibility of PCOS plays a role in glucose and lipid metabolism in Chinese PCOS patients. It may also be correlated with attack rate of diabetes and tumor in the family history of PCOS patients.

Topics: Adolescent; Adult; Blood Glucose; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Lipids; Polycystic Ovary Syndrome; Polymorphism, Single Nucleotide; Triglycerides; Young Adult

Exercise training plays a major role in the improving physiology of diabetes. Herein we aimed to investigate the influence of exercise upon the calcium-dependent calpain-isoform expressions of lean or obese Zucker rats, a model of obesity and type II diabetes (NIDDM). Five-month-old rats were divided: (1) obese sedentary (OS, n=7); (2) obese exercise (OE, n=7); (3) lean sedentary (LS, n=7); (4) lean exercise (LE, n=7). After 2-month exercise (treadmill running), the body weight (BW) and expression of calpain 10, mu-calpain, and m-calpain in skeletal muscles were determined by RT-PCR, using beta-actin as internal standard. We found exercise is useful for BW lossing, especially in the obese rats. The BW difference between OS and OE rats (69 g vs. 18.2 g) was more significantly than that between LS and LE rats (41.8 g vs. 28.7 g). The calpain 10 expression of LS rats (0.965) was lower than that of LE rats (1.006), whereas those of OS and OE were comparable. The mu- or m-calpain expressions of sedentary groups (OS, LS) was significantly higher than those of exercise groups (OE, LE). The mu-calpain expression (1.13/0.92) and m-calpain expression (1.01/0.99) of OS/LS rats was significantly higher than those of OE/LE rats [1.07/0.9 (micro-calpain); 0.97/0.95 (m-calpain)]. We concluded that the micro- or m-calpains in skeletal muscle are regulated by exercise in both lean and obese Zucker rats. Exercise and BW controlling might improve the physiopathology of obesity and diabetes. Both micro- or m-calpains might become useful markers for prognoses of diabetes.

Topics: Animals; Blotting, Western; Body Weight; Calpain; Diabetes Mellitus, Type 2; Muscle, Skeletal; Obesity; Physical Conditioning, Animal; Rats; Rats, Zucker; Reverse Transcriptase Polymerase Chain Reaction

Our objective was to investigate the effect of lipid-induced insulin resistance and type 2 diabetes on skeletal muscle calpain-10 mRNA and protein levels.. In the first part of this study, 10 healthy subjects underwent hyperinsulinemic euglycemic (4.5 mmol/liter) clamps for 6 h with iv infusion of either saline or a 20% Intralipid emulsion (Fresenius Kabi AG, Bad Homburg, Germany). Skeletal muscle biopsies were taken before and after 3- and 6-h insulin infusion and analyzed for calpain-10 mRNA and protein expression. In the second part of the study, muscle samples obtained after an overnight fast in 10 long-standing, sedentary type 2 diabetes patients, 10 sedentary, weight-matched, normoglycemic controls, and 10 age-matched, endurance-trained cyclists were analyzed for calpain-10 mRNA and protein content.. Intralipid infusion in healthy subjects reduced whole body glucose disposal by approximately 50% (P<0.001). Calpain-10 mRNA (P=0.01) but not protein content was reduced after 6-h insulin infusion in both the saline and Intralipid emulsion trials. Skeletal muscle calpain-10 mRNA and protein content did not differ between the type 2 diabetes patients and normoglycemic controls, but there was a strong trend for total calpain-10 protein to be greater in the endurance-trained athletes (P=0.06).. These data indicate that skeletal muscle calpain-10 expression is not modified by insulin resistance per se and suggest that hyperinsulinemia and exercise training may modulate human skeletal muscle calpain-10 expression.

Topics: Adult; Calpain; Diabetes Mellitus, Type 2; Fat Emulsions, Intravenous; Glucose Transporter Type 4; Humans; Insulin; Insulin Resistance; Male; Middle Aged; Muscle, Skeletal; RNA, Messenger

Pancreatic beta-cell death is a critical event in type 1 diabetes, type 2 diabetes, and clinical islet transplantation. We have previously shown that prolonged block of ryanodine receptor (RyR)-gated release from intracellular Ca(2+) stores activates calpain-10-dependent apoptosis in beta-cells. In the present study, we further characterized intracellular Ca(2+) channel expression and function in human islets and the MIN6 beta-cell line. All three RyR isoforms were identified in human islets and MIN6 cells, and these endoplasmic reticulum channels were observed in close proximity to mitochondria. Blocking RyR channels, but not sarco/endoplasmic reticulum ATPase (SERCA) pumps, reduced the ATP/ADP ratio. Blocking Ca(2+) flux through RyR or inositol trisphosphate receptor channels, but not SERCA pumps, increased the expression of hypoxia-inducible factor (HIF-1beta). Moreover, inhibition of RyR or inositol trisphosphate receptor channels, but not SERCA pumps, increased the expression of presenilin-1. Both HIF-1beta and presenilin-1 expression were also induced by low glucose. Overexpression of presenilin-1 increased HIF-1beta, suggesting that HIF is downstream of presenilin. Our results provide the first evidence of a presenilin-HIF signaling network in beta-cells. We demonstrate that this pathway is controlled by Ca(2+) flux through intracellular channels, likely via changes in mitochondrial metabolism and ATP. These findings provide a mechanistic understanding of the signaling pathways activated when intracellular Ca(2+) homeostasis and metabolic activity are suppressed in diabetes and islet transplantation.

Topics: Adenosine Diphosphate; Adenosine Triphosphate; Aryl Hydrocarbon Receptor Nuclear Translocator; Calcium; Calcium Signaling; Calpain; Cells, Cultured; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Endoplasmic Reticulum; Glucose; Homeostasis; Humans; Insulin-Secreting Cells; Islets of Langerhans Transplantation; Mitochondria; Presenilin-1; Protein Isoforms; Ryanodine Receptor Calcium Release Channel; Sarcoplasmic Reticulum Calcium-Transporting ATPases

Genome-wide analyses of the genetic predisposition to type 2 diabetes mellitus (T2DM) in different isolates and populations have identified regions of interest called non insulin-dependent diabetes mellitus (NIDDM) 1, 2, 3 and 4. At the NIDDM1 locus (2q37.3), calpain-10 (CAPN10) encodes for a ubiquitously expressed protease implicated in the two fundamental pathophysiological aspects of T2DM. This is a report of the results of a study of the association of four CAPN10 polymorphisms with T2DM in the Tunisian population.. A total of 222 T2DM patients with a diabetes duration of 10 years or more and 206 healthy controls were enrolled to analyze the frequency distribution of four CAPN10 polymorphisms (UCSNP-43, UCSNP-19, UCSNP-110 and UCSNP-63) using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in the Tunisian population. We also investigated the association of T2DM with different haplotypes and haplotype combinations.. Only the A allele of UCSNP-43 showed an association with T2DM (odds ratio, OR=1.86). We also identified a novel combination of haplotypes (121/221) defined by three polymorphisms (UCNSP-43, -19 and -63) that is associated with an increased risk of T2DM (OR=2.38).. In this study involving the Tunisian population, we identified genetic variants within CAPN10 that are linked with T2DM and a novel haplotype combination, 121/221, associated with an increased susceptibility to T2DM.

Topics: Aged; Calpain; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genome, Human; Humans; Male; Middle Aged; Polymorphism, Genetic; Reference Values; Tunisia

Increased permeability to albumin is a well-known feature of diabetic microvasculature and a negative prognostic factor of vascular complications. The mechanisms responsible for loss of the physiological albumin barrier in diabetic organs remain only partially understood. We have recently demonstrated that the protease mu-calpain is activated in hyperglycemia, which causes endothelial dysfunction and vascular inflammation. In the present study, we investigated whether mu-calpain is involved in the hyperpermeability of the diabetic vasculature. We also investigated the mechanistic roles of hyperglycemia and leukocyte adhesion in this process. Albumin permeability in the intact microcirculation of the Zucker diabetic fatty (ZDF) rat was quantified by intravital microscopy. Extravasation of albumin in the microcirculation of ZDF rats was significantly increased when compared with nondiabetic Zucker lean (ZL) rats. Microvascular albumin leakage was prevented by either antisense depletion of mu-calpain or pharmacological inhibition of calpain in vivo. Calpain inhibition also attenuated urinary albumin excretion in ZDF rats. Glucose concentrations in the range of those found in the blood of ZDF rats increased albumin permeability in nondiabetic ZL rats. Thus, this demonstrates a mechanistic role for hyperglycemia in the hypermeability of diabetes. Depletion of polymorphonuclear leukocytes in vivo failed to prevent glucose-induced hypermeability, which suggests that hyperglycemia can disrupt the physiological endothelial cell barrier of the microcirculation, even in the absence of increased overt leukocyte-endothelium interactions.

Topics: Albumins; Animals; Calpain; Capillary Permeability; Diabetes Mellitus, Type 2; Dipeptides; Disease Models, Animal; Endothelium, Vascular; Enzyme Inhibitors; Hyperglycemia; Leukocytes; Male; Microcirculation; Oligodeoxyribonucleotides, Antisense; Rats; Rats, Zucker; Vascular Diseases

The mRNA concentration of CAPN10, a T2D susceptibility gene was measured in white blood cells of T2D and healthy subjects, as well as the transcript half-life in two SNP-43 genotyped human cell lines, to evaluate a possible relationship between this SNP-43 and the transcript half-life. T2D patients with the SNP-43 G-allele had 4.6-fold more CAPN10 transcripts compared to subjects with the A-allele. The mRNA half-life of this transcript in 293T cells (SNP-43 G/G) and Jurkat cells (SNP-43 A/A) was of 8h. We provide evidence that in T2D subjects the G-allele increases the CAPN10 mRNA levels. We propose a defective CAPN10 pre-mRNA processing is responsible for the decreased levels of SNP-43 A-allele transcripts in peripheral white cells of healthy and T2D individuals.

Topics: Adult; Alleles; Calpain; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genotype; Humans; Jurkat Cells; Male; Middle Aged; Polymorphism, Single Nucleotide; RNA Precursors; RNA Splicing; RNA, Messenger

Calpain-10 (CAPN10) protein may play a role in glucose metabolisms, pancreatic beta-cell insulin secretion and thermogenesis. Emerging evidence has implicated a role of CAPN10 genetic variants in the risk of type 2 diabetes mellitus (T2DM). Previous association studies, however, have focussed only on several variants initially reported and provided inconsistent results. We conducted a large nested case-control study to comprehensively investigate the associations between common variations in CAPN10 gene and T2DM risk among postmenopausal women aged 50-79 years from the Women's Health Initiative Observational Study. After comprehensive screening in 244 randomly chosen control samples (n = 61 for each of four ethnic groups), we selected a total of 12 tagging single nucleotide polymorphisms (tSNPs) spanning 91 kb in CAPN10 and genotyped them in 1543 diabetes cases and 2132 matched controls (including 968 cases and 968 controls for whites, 366 and 732 for blacks, 152 and 303 for Hispanics and 98 and 195 for Asian/Pacific Islanders). There were no significant associations between any individual tSNP and T2DM, within either the full study sample or any specific ethnic group. Nor was there any evidence of association between common CAPN10 haplotypes and diabetes risk (global tests for differences in risk were P = 0.31 for overall common haplotypes, P = 0.44 for haplotypes in block 1 and P = 0.37 for haplotypes in block 2). In conclusion, we did not observe any significant associations of the common SNPs or haplotypes across the CAPN10 gene with diabetes risk in our large and ethnically diverse cohort of postmenopausal women.

Topics: Aged; Calpain; Case-Control Studies; Cohort Studies; Diabetes Mellitus, Type 2; Ethnicity; Female; Genetic Variation; Haplotypes; Humans; Linkage Disequilibrium; Menopause; Middle Aged; Polymorphism, Single Nucleotide; Risk Factors; United States

Calpain-10 (CAPN10) has been identified as a susceptibility gene in type 2 diabetes mellitus (T2DM) and insulin resistance. The present study aimed to identify the effects of genetic variations in the CAPN10 gene on the development of type 2 diabetes and hypertension in northern Han Chinese population.. We performed a case-control study and genotyped single nucleotide polymorphism (SNP)-44, -43, -19 and -63 of CAPN10 gene in 1046 subjects from the northern China, including 493 patients with T2DM and hypertension and 553 age- and gender-matched normal healthy controls.. Univariate analysis showed that the four polymorphisms were not independently associated with T2DM and hypertension. However, the frequency distributions of SNP-44 allele C (allele 2) (17.89% vs 9.80%, P = 0.0016) and genotype CC (22) (4.21% vs 1.01%, P = 0.0059) in obese patients (body mass index > or = 30 kg/m2) were different from those in non-obese patients. Logistic regression analyses revealed that carriers of the 1112/1221 diplotype had a significantly lower odds ratio for diabetes and hypertension (OR = 0.399, 95% CI, 0.196 - 0.814, P = 0.0115). The 1112/1121 diplotype associated with significantly increased risk of type 2 diabetes in Mexican-American was not associated with the increased risk in Chinese.. These results suggested that CAPN10 gene variations might play roles in the risk of diabetes and hypertension in northern Han Chinese population.

Topics: Adult; Aged; Calpain; China; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Haplotypes; Humans; Hypertension; Linkage Disequilibrium; Male; Middle Aged; Polymorphism, Single Nucleotide; Quantitative Trait Loci

Linkage- and association-based approaches have been applied to attempt to unravel the genetic predisposition for complex diseases. However, studies often report contradictory results even when similar population backgrounds are investigated. Unrecognized population substructures could possibly explain these inconsistencies. In an apparently homogeneous German sample of 612 patients with type 2 diabetic and end-stage diabetic nephropathy and 214 healthy controls, we tested for hidden population substructures and their possible effects on association. Using a genetic vector space analysis of genotypes of 20 microsatellite markers, we identified four distinct subsets of cases and controls. The significance of these substructures was demonstrated by subsequent association analyses, using three genetic markers (UCSNP-43,-19,-63; intron 3 of the calpain-10 gene). In the undivided sample, we found no association between individual SNPs or any haplogenotypes (ie the genotype combination of two multilocus haplotypes) and type 2 diabetes. In contrast, when analyzing the four groups separately, we found that there was evidence for association of the common C allele of UCSNP-63 with the trait in the largest group (n=547 cases/101 controls; P=0.002). In this subset haplotype 112 was more frequent in controls than in cases (P=0.006; haplogenotype 112/121: odds ratio (OR)=0.27, 95% confidence intervals (CI)=0.13-0.57), indicating a protective effect against the development of type 2 diabetes. Our study demonstrates that unconsidered population substructures (ethnicity-dependent factors) can severely bias association studies.

Topics: Bias; Calpain; Diabetes Mellitus, Type 2; DNA Primers; Female; Genetic Markers; Genetic Predisposition to Disease; Genetic Variation; Genetics, Population; Genotype; Germany; Haplotypes; Humans; Linkage Disequilibrium; Male; Microsatellite Repeats; Polymorphism, Single Nucleotide

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 4; Humans; Insulin-Secreting Cells; Lipase; Mutation; Organ Specificity; Pancreas, Exocrine; Polymorphism, Genetic

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. The aim of the present study was to investigate the role of CALPAIN-5 (CAPN5) gene in PCOS susceptibility.. We analysed four intronic polymorphisms of the CAPN5 gene in 148 well-characterized women with PCOS and 606 unrelated controls. We performed a case-control study and an intracohort analysis of clinical characteristics associated with PCOS.. Analysis of haplotypes distribution between PCOS population compared to controls showed a strong deviation (P = 0.00029). The haplotypes GGCA and GGTG were overrepresented in PCOS patients (P = 0.009 and P = 0.001, respectively). In addition, we identified several CAPN5 haplotypes associated with phenotypic differences observed between PCOS patients, such as the presence of obesity (P = 0.02), cardiovascular complications (P = 0.02), familial antecedents of obesity (P = 0.003) and of hypertension (P = 0.007) and type 2 diabetes mellitus aggregation (P = 0.04).. These results suggest a role of CAPN5 gene in PCOS susceptibility in humans. Moreover, novel candidate risk alleles have been identified, within CAPN5 gene, which could be associated with important phenotypic and prognosis differences observed in PCOS patients.

Topics: Alleles; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Hypertension; Obesity; Phenotype; Polycystic Ovary Syndrome; Polymorphism, Single Nucleotide; Risk Factors

Topics: Body Mass Index; Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genetic Testing; Genotype; Humans; PPAR gamma; Predictive Value of Tests; Prognosis; Risk Factors; Sensitivity and Specificity

Patients with metabolic syndrome are at increased risk of developing cardiovascular disease. The combinations of the haplotype created by the alleles of three single nucleotide polymorphisms (SNPs): SNP-43, -19, and -63 of the Calpain-10 gene (CAPN10), have been reported to be associated with the risk of type 2 diabetes in many populations. The aim of this study was to examine the association of the CAPN10 polymorphism with metabolic syndrome in patients with type 2 diabetes in Korea. Overall, 382 patients with type 2 diabetes were enrolled in this study. All the subjects were genotyped according to CAPN10 SNP-43, -19, and -63. The restriction fragment length polymorphism method was used for the three SNPs. The baseline presence of components of metabolic syndrome was determined. Two hundred and sixty-five (69.4%) patients had metabolic syndrome. Patients with the 111/121 haplotype combination showed a higher risk of hypertension than the other haplotype combinations (odd ratio (OR)=2.334, P=0.010). Patients with the 111/121 haplotype combination had a significantly high risk of metabolic syndrome (OR=1.927, P=0.042). The results of this study suggest that a novel 111/121 haplotype combination created by the CAPN10 SNP-43, -19, and -63 increases the susceptibility to the metabolic syndrome in patients with type 2 diabetes.

Topics: Adult; Blood Glucose; Blood Pressure; Calpain; Cholesterol, HDL; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Glycated Hemoglobin; Haplotypes; Humans; Korea; Male; Middle Aged; Odds Ratio; Polymorphism, Single Nucleotide; Triglycerides

Genetic variations in the Calpain-10 gene, CAPN10, have been reported to be associated with the risk of type 2 diabetes mellitus (T2DM) in Mexican-Americans and Northern Europeans whereas these variations are not associated with T2DM in other populations. The aim of this study was to determine whether there is an association between specific CAPN10 diplotype (SNP-43, -19, and -63) and T2DM in the Korean population. Overall, 454 Korean patients with T2DM (male 230, female 224) and 236 non-diabetic controls (male 124, female 112) with no family history of diabetes were enrolled in this study. All the subjects were genotyped according to CAPN10 SNP-43, -19, and -63. The restriction fragment length polymorphism method was used for the three SNPs. There were eight estimated haplotype allelic variations. After adjusting for gender and age, the 111 haplotype was associated with a high risk of T2DM (P <0.0001). The 111/121 diplotype was associated with a high risk of T2DM (odds ratio =2.580, 95% confidence interval =1.602-4.155, P =0.001). The high-risk haplotype (112/121) in Mexican-Americans was not significant in our study population. In conclusion, we found that a novel 111/121 diplotype in Calpain-10 gene is associated with T2DM in the Korean population.

Topics: Adult; Alleles; Asian People; Calpain; Case-Control Studies; Confidence Intervals; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Variation; Haplotypes; Humans; Male; Middle Aged; Odds Ratio; Polymorphism, Restriction Fragment Length; Polymorphism, Single Nucleotide; Risk Factors

We present data from a genome-wide scan identifying genetic factors conferring susceptibility to type 2 diabetes. The linkage analysis was based on 59 families from northern Sweden, consisting of a total of 129 cases of type 2 diabetes and 19 individuals with impaired glucose tolerance. Model-free linkage analysis revealed a maximum multipoint logarithm of odds score of 3.19 for D2S2987 at 267.7 cM (P=0.00058), suggesting that a gene conferring susceptibility to type 2 diabetes in the northern Swedish population resides in the 2q37 region. These data replicate, in a European population, previously identified linkage of marker loci in this region to type 2 diabetes in Mexican Americans. In contrast, no evidence in support of association to the previously identified single nucleotide polymorphisms in the calpain-10 gene was observed in a case-control cohort derived from the same population.

Topics: Adult; Alleles; Calpain; Diabetes Mellitus, Type 2; Gene Frequency; Genetic Linkage; Genetic Predisposition to Disease; Genome, Human; Genotype; Glucose Intolerance; Haplotypes; Humans; Lod Score; Logistic Models; Middle Aged; Polymorphism, Single Nucleotide; Sweden; White People

The mechanisms by which the calpain-10 gene (CAPN10) affects the risk of type 2 diabetes are unclear. Therefore, we investigated the effects of four polymorphisms in CAPN10 (single nucleotide polymorphism [SNP]-43, SNP-44, Insertion/Deletion [Indel]-19 and SNP-63) on insulin secretion, insulin action and abdominal fat distribution in offspring of patients with type 2 diabetes.. Insulin secretion was determined by an IVGTT, insulin action by the hyperinsulinaemic-euglycaemic clamp and abdominal fat distribution by computed tomography in 158 non-diabetic offspring (age 34.9+/-6.3 years [mean+/-SD], BMI 26.2+/-4.9 kg/m(2)) of type 2 diabetic patients.. SNP-43 (p=0.009 over the three genotypes, adjusted for age, sex, BMI and family relationship) and haplotypes carrying the A allele of SNP-43 were associated with intra-abdominal fat area. The A allele of SNP-43 was associated with intra-abdominal fat area in men (p=0.014) but not in women. SNP-44, InDel-19 and SNP-63 were not associated with intra-abdominal fat area or insulin action. Furthermore, we demonstrated in a separate sample of middle-aged men (n=234) who had a history of type 2 diabetes in first-degree relatives that the A allele of SNP-43 was associated with a large waist circumference, and high insulin levels in an OGTT.. SNP-43 of CAPN10 may contribute to the risk of diabetes by regulating abdominal obesity in subjects with high risk of type 2 diabetes.

Topics: Abdominal Fat; Adult; Aged; Calpain; Diabetes Mellitus, Type 2; Female; Finland; Genetic Predisposition to Disease; Glucose Tolerance Test; Humans; Linkage Disequilibrium; Male; Middle Aged; Obesity; Polymorphism, Single Nucleotide; Risk

The first type 2 diabetes (T2D) gene to be identified in a genome wide scan followed by positional cloning was CAPN10 encoding the cysteine protease calpain-10. Subsequently, a large number of studies have investigated variation in CAPN10 in relation to T2D. Two CAPN10 single nucleotide polymorphisms (SNPs), the SNP43 (rs3792267) and the SNP44 (rs2975760), have been associated with T2D in some, but not all studies conducted in a wide range of ethnicities. We investigated the two SNPs for association with T2D in a relatively large, homogenous population of Danish whites (n = 1359 T2D cases, n = 4659 normoglycemic and glucose-tolerant control subjects), however, no significant associations of the SNP43 or the SNP44 variant with T2D were found. Neither were the two variants associated with obesity, and no association of either variant with diabetes-related quantitative traits was found in a study involving a population-based sample of 5698 middle-aged subjects. Meta-analyses, however, of the present and previously published studies involving 15,368 (SNP43) or 13,628 (SNP44) subjects yielded odds ratios of 1.09 (95% CI 1.02-1.16, p = 0.007) and 1.15 (1.07-1.23, p = 0.0002), respectively, for association with T2D. In conclusion, in a relatively large study sample of whites we found no consistent evidence of association of the CAPN10 SNP43 or SNP44 with T2D, obesity, or related quantitative traits, although meta-analyses of these two CAPN10 SNPs demonstrated an association with T2D.

Topics: Blood Glucose; Body Mass Index; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Insulin; Male; Middle Aged; Obesity; Polymorphism, Single Nucleotide; White People

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Markers; Genetic Predisposition to Disease; Genetic Testing; Humans; Nuclear Proteins; PPAR gamma; TCF Transcription Factors; Transcription Factor 7-Like 2 Protein

We outline a general coalescent framework for using genotype data in linkage disequilibrium-based mapping studies. Our approach unifies two main goals of gene mapping that have generally been treated separately in the past: detecting association (i.e., significance testing) and estimating the location of the causative variation. To tackle the problem, we separate the inference into two stages. First, we use Markov chain Monte Carlo to sample from the posterior distribution of coalescent genealogies of all the sampled chromosomes without regard to phenotype. Then, averaging across genealogies, we estimate the likelihood of the phenotype data under various models for mutation and penetrance at an unobserved disease locus. The essential signal that these models look for is that in the presence of disease susceptibility variants in a region, there is nonrandom clustering of the chromosomes on the tree according to phenotype. The extent of nonrandom clustering is captured by the likelihood and can be used to construct significance tests or Bayesian posterior distributions for location. A novelty of our framework is that it can naturally accommodate quantitative data. We describe applications of the method to simulated data and to data from a Mendelian locus (CFTR, responsible for cystic fibrosis) and from a proposed complex trait locus (calpain-10, implicated in type 2 diabetes).

Topics: Alleles; Bayes Theorem; Calpain; Chromosome Mapping; Computer Simulation; Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator; Diabetes Mellitus, Type 2; Disease Susceptibility; Genetic Variation; Haplotypes; Humans; Likelihood Functions; Linkage Disequilibrium; Markov Chains; Models, Genetic; Monte Carlo Method; Mutation; Pedigree; Penetrance; Polymorphism, Single Nucleotide; Quantitative Trait, Heritable; Recombination, Genetic

To investigate whether the three single nucleotide polymorphisms (SNPs), SNP-43, -56, and -63 of CAPN10 were associated with type 2 diabetes in a West African cohort.. A total of 347 diabetic subjects and 148 unaffected controls from four ethnic groups in two West African countries were enrolled in this study. After genotyping three SNPs of CAPN10 and one SNP from CYP19, the allele, genotype, and haplotype frequencies as well as the odds ratios were calculated to test their association with type 2 diabetes.. None of the alleles or genotypes was associated with type 2 diabetes. Although statistical analysis indicated that haplotype 221 was associated with type 2 diabetes (OR, 3.765; 95% CI, 1.577-8.989) in the two ethnic groups of Nigeria, the same haplotype did not show any association with type 2 diabetes in the two ethnic groups in Ghana (OR, 0.906; 95% CI, 0.322-2.552).. Considering the relatively low frequency of haplotype 221 and that none of the haplotypes including 221 was associated with any of the diabetes-related quantitative traits tested, it is concluded that SNP-43, -56, and -63 of the CAPN10 gene variants may play a limited role in the risk of type 2 diabetes risks in this cohort of West Africans.

Topics: Alleles; Black People; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Ghana; Haplotypes; Humans; Male; Middle Aged; Nigeria; Polymorphism, Single Nucleotide

Variation in the gene encoding the cysteine protease calpain-10 has been linked and associated with risk of type 2 diabetes. We have examined the effect of three polymorphisms in the calpain-10 gene (SNP-43, Indel-19, and SNP-63) on the development of type 2 diabetes in the Japanese population in a pooled analysis of 927 patients and 929 controls. We observed that SNP-43, Indel-19, and SNP-63 either individually or as a haplotype were not associated with altered risk of type 2 diabetes with the exception of the rare 111/221 haplogenotype (odds ratio (OR) =3.53, P=0.02). However, stratification based on the median age-at-diagnosis in the pooled study population (<50 and > or =50 years) revealed that allele 2 of Indel-19 and the 121 haplotype were associated with reduced risk in patients with later age-at-diagnosis (age-at-diagnosis > or =50 years OR=0.82 and 0.80, respectively; P=0.04 and 0.02). Thus, variation in the calpain-10 gene may affect risk of type 2 diabetes in Japanese, especially in older individuals.

Topics: Adult; Age of Onset; Aged; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Japan; Male; Middle Aged; Polymorphism, Genetic; Risk Factors

A positional cloning study of type 2 diabetes in Mexican Americans identified a region, termed "NIDDM1," on chromosome 2q37 with significant linkage evidence. Haplotype combinations at the calpain-10 gene (CAPN10) within this region were shown to increase diabetes risk in several populations. On the basis of the thrifty genotype hypothesis, variants that increase susceptibility to type 2 diabetes under modern lifestyle conditions provided a survival advantage in past environments by increasing the efficiency of energy use and storage. Here, our goal is to make inferences about the evolutionary forces shaping variation in genes in the NIDDM1 region and to investigate the population genetics models that may underlie the thrifty genotype hypothesis. To this end, we surveyed sequence variation in CAPN10 and in an adjacent gene, G-protein-coupled receptor 35 (GPR35), in four population samples from different ethnic groups. These data revealed two distinct deviations from the standard neutral model in CAPN10, whereas GPR35 variation was largely consistent with neutrality. CAPN10 showed a significant deficit of variation in the haplotype class defined by the derived allele at SNP44, a polymorphism that is significantly associated with diabetes in meta-analysis studies. This suggests that this haplotype class was quickly driven to high frequency by positive natural selection. Interestingly, the derived allele at SNP44 is protective against diabetes. CAPN10 also showed a local excess of polymorphism and linkage disequilibrium decay in intron 13. Simulations show that this pattern may be explained by long-standing balancing selection that maintains multiple selected alleles. Alternatively, it is possible that the local mutation and recombination rates changed since the divergence of human and chimpanzee; this scenario does not require the action of natural selection on intron 13 variation.

Topics: Calpain; Diabetes Mellitus, Type 2; Gene Frequency; Genetic Predisposition to Disease; Genetic Variation; Humans; Mexican Americans; Models, Genetic; Polymorphism, Genetic; Receptors, G-Protein-Coupled; Selection, Genetic

Cardiovascular complications are the leading cause of morbidity and mortality in diabetic patients. Endothelial dysfunction with impaired endothelial nitric oxide (NO) synthase (eNOS) activity is a widely accepted cause of diabetic vasculopathy. The mechanisms of endothelial dysfunction in diabetes remain elusive, thus limiting effective therapeutic interventions. We report novel evidence demonstrating that the calcium-dependent protease calpain causes endothelial dysfunction and vascular inflammation in the microcirculation of the ZDF (Zucker diabetic fatty) rat, a genetic rat model of type 2 diabetes. We found evidence of increased calpain activity and leukocyte trafficking in the microcirculation of ZDF rats. Inhibition of calpain activity significantly attenuated leukocyte-endothelium interactions in the vasculature of ZDF rats. Expression of cell adhesion molecules in the vascular endothelium of ZDF rats was consistently increased, and it was suppressed by calpain inhibition. In vivo measurement of endothelial NO availability demonstrated a 60% decrease in NO levels in the microcirculation of diabetic rats, which was also prevented by calpain inhibition. Immunoprecipitation studies revealed calpain-dependent loss of association between eNOS and the regulatory protein heat shock protein 90. Collectively, these data provide evidence for a novel mechanism of endothelial dysfunction and vascular inflammation in diabetes. Calpains may represent a new molecular target for the prevention and treatment of diabetic vascular complications.

Topics: Animals; Calpain; Diabetes Mellitus, Type 2; Endothelium, Vascular; HSP90 Heat-Shock Proteins; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Rats; Rats, Zucker

The powerful relation between atherosclerosis and diabetes may have a common genetic basis. However, few genes predisposing to both have been identified. Calpain-10 (CAPN10) was the first gene for type 2 diabetes identified by positional cloning, wherein a combination of haplotypes conferred increased risk of diabetes. We sought to determine whether CAPN10 influences subclinical atherosclerosis. Among nondiabetic subjects from 85 Mexican-American families with a history of coronary artery disease, subclinical atherosclerosis was assessed by common carotid artery intima-media thickness (IMT), insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamp, and insulin secretion was estimated by the oral glucose tolerance test. These phenotypes were tested for association with CAPN10 haplotypes. Haplotype 1112 (of single nucleotide polymorphisms [SNPs] 44, 43, 56, and 63) was associated with increased IMT, while haplotype 1221 was associated with decreased IMT. The 112/121 haplotype combination (of SNPs 43, 56, and 63), originally found to confer increased risk for diabetes, was associated with the largest IMT in our study population. CAPN10 was also associated with both insulin sensitivity and insulin secretion. Covariate analysis suggested that CAPN10 affects IMT independently of these diabetes-related phenotypes. The fact that the diabetes gene CAPN10 also influences the risk for atherosclerosis shows that inherited factors may underlie the frequent co-occurrence of these two conditions.

Topics: Adolescent; Adult; Aged; Arteriosclerosis; Calpain; Carotid Artery Diseases; Coronary Disease; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Insulin Resistance; Male; Mexican Americans; Middle Aged; Phenotype; Tunica Intima

Variants of calpain-10 gene (CAPN 10) have recently been reported to be associated with type 2 diabetes (T2DM). Haplotype combination 112/121 defined by three single nucleotide polymorphisms (SNPs) (UCSNP-43, -19 and -63) of CAPN 10 conferred the highest risk for T2DM in Mexican-Americans. In this study, we aim to examine whether these genetic variants contribute to the susceptibility for T2DM in a Chinese population. The frequencies of these three SNPs were determined in 168 patients with T2DM and 104 controls. Distribution of alleles, genotypes and haplotypes at three loci were not significantly different between the two groups. No difference was observed in the 112/121 haplotype combination distribution. However, haplotype combination 112/221 was more prevalent in the control group than in T2DM group (16.35% versus 7.14%, p = 0.025). Control subjects with haplotype combination 112/121 had higher serum cholesterol level than others without haplotype combination 112/121 (5.7 +/- 1.4 versus 5.2 +/- 0.7, p = 0.011). Our results suggest that haplotype combination 112/221 associated with reduced risk for T2DM and haplotype combination 112/121 might be a risk factor for increased serum cholesterol in Chinese population.

Topics: Asian People; Calpain; China; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Carrier Screening; Haplotypes; Humans; Male; Metabolic Syndrome; Middle Aged; Polymorphism, Genetic; Risk Factors

Variation in the calpain 10 gene has been reported to increase susceptibility to type 2 diabetes. Part of this susceptibility appears to be mediated by a decrease in whole body insulin sensitivity. As skeletal muscle is the primary tissue site of the peripheral insulin resistance in type 2 diabetes, the aim of this study was to use a human skeletal muscle cell culture system to explore the effects of calpain inhibition on insulin action. Calpain 10 mRNA and protein expression was examined in cultured myoblasts, myotubes, and whole skeletal muscle from non-diabetic subjects using RT-PCR and Western blotting. Changes in insulin-stimulated glucose uptake and glycogen synthesis in response to the calpain inhibitors ALLN and ALLM were measured. Calpain 10 expression was confirmed in cultured human myoblasts, myotubes, and native skeletal muscle. Insulin-stimulated glucose uptake was significantly decreased following preincubation with ALLN [404+/-40 vs 505+/-55 (mean+/-SEM)pmol/mg/min; with vs without ALLN: p = 0.04] and ALLM [455+/-38 vs 550+/-50 pmol/mg/min; with vs without ALLM: p = 0.025] in day 7 fused myotubes, but not in myoblasts. Neither ALLN nor ALLM affected insulin-stimulated glycogen synthesis in myoblasts or myotubes. These studies confirm calpain 10 expression in cultured human muscle cells and support a role for calpains in insulin-stimulated glucose uptake in human skeletal muscle cells that may be relevant to the pathogenesis of the peripheral insulin resistance in type 2 diabetes.

Topics: Base Sequence; Biological Transport; Calpain; Cell Culture Techniques; Cells, Cultured; Diabetes Mellitus, Type 2; DNA Primers; Gene Expression Regulation, Enzymologic; Genetic Predisposition to Disease; Glucose; Glycogen; Humans; Insulin; Insulin Resistance; Muscle, Skeletal; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transcription, Genetic

It has been proposed that variation in calpain 10 (CAPN10) contributes to the risk of type 2 diabetes (T2D). A previous survey of CAPN10 in ethnically diverse populations revealed an intronic region with a significant excess of polymorphism levels relative to inter-species sequence divergence, suggesting that this region was the target of long-standing balancing selection. Based on the thrifty genotype hypothesis, variation that increases risk to T2D in contemporary humans at one time conferred a survival advantage in ancestral populations. Thus, the signature of positive natural selection in a T2D candidate gene could identify a genomic region containing variation that influences disease susceptibility. Here, we investigate this hypothesis by re-sequencing the CAPN10 region with unusual polymorphism levels in T2D cases and controls (n=91) from a Mexican American (MA) population, and by using networks to infer the evolutionary relationships between the major haplotypes. Haplotype tag SNPs (htSNPs) were then selected in each population sample and in MA cases and controls. By placing the htSNPs on the haplotype network, we investigate how cross-population differences in CAPN10 genetic architecture may affect the detection of the disease association. Interestingly, despite the small scale of our case-control study, we observe a nearly significant signal of association between T2D and variation in the putative target of balancing selection. Finally, we use phylogenetic shadowing across 10 primate species to search for conserved non-coding elements that may affect the expression and function of CAPN10. These elements are postulated to be the targets of long-standing balancing selection.

Topics: Animals; Calpain; Diabetes Mellitus, Type 2; Gene Expression Regulation; Genetic Linkage; Genetic Predisposition to Disease; Humans; Phylogeny; Polymorphism, Single Nucleotide; Primates; Selection, Genetic

We investigated the patterns and extent of linkage disequilibrium (LD) in the vicinity of the type 2 diabetes gene calapin-10 (CAPN10) in Mexican Americans, European Americans, African Americans, and Chinese Americans. We found that CAPN10 occurs within a single block of high LD and that LD decays rapidly outside of the gene. This reduces the likelihood that associations between CAPN10 polymorphisms and type 2 diabetes could be attributed to variation at some distance from CAPN10. We also consistently observed that cases have more extensive LD than control subjects and that cases from families with evidence for linkage have more extensive LD than cases from families without evidence for linkage. These observations further suggest that there are one or more relatively common alleles increasing risk of type 2 diabetes in this local region.

Topics: Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Humans; Linkage Disequilibrium; Racial Groups; Risk Factors

Gestational diabetes mellitus (GDM) and type 2 diabetes share a common pathophysiological background, including beta cell dysfunction and insulin resistance. In addition, women with GDM are at increased risk of developing type 2 diabetes later in life. Our aim was to investigate whether, like type 2 diabetes, GDM has a genetic predisposition by studying five common polymorphisms in four candidate genes that have previously been associated with type 2 diabetes.. We studied 1,777 unrelated Scandinavian women (588 with GDM and 1,189 pregnant non-diabetic controls) for polymorphisms in the genes encoding potassium inwardly rectifying channel subfamily J, member 11 (KCNJ11 E23K), insulin receptor substrate 1 (IRS1 G972R), uncoupling protein 2 (UCP2 -866G-->A) and calpain 10 (CAPN10 SNP43 and SNP44).. The EE, EK and KK genotype frequencies of the KCNJ11 E23K polymorphism differed significantly between GDM and control women (31.5, 52.7 and 15.8% vs 37.3, 48.8 and 13.9%, respectively; p=0.050). In addition, the frequency of the K allele was increased in women with GDM (odds ratio [OR]=1.17, 95% CI 1.02-1.35; p=0.027), and this effect was greater under a dominant model (KK/EK vs EE) (OR=1.3, 95% CI 1.05-1.60; p=0.016). Analysis of the IRS1 G972R polymorphism showed that RR homozygosity was found exclusively in women with GDM (91.0, 8.3 and 0.7% vs 90.7, 9.3 and 0.0% for GG, GR and RR genotypes, respectively; p=0.014). The genotype and allele frequencies of the other polymorphisms studied were not statistically different between the GDM and control women.. The E23K polymorphism of KCNJ11 seems to predispose to GDM in Scandinavian women.

Topics: Adult; Alleles; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Insulin Receptor Substrate Proteins; Insulin Resistance; Insulin-Secreting Cells; Ion Channels; Membrane Transport Proteins; Mitochondrial Proteins; Odds Ratio; Phosphoproteins; Polymorphism, Genetic; Potassium Channels, Inwardly Rectifying; Pregnancy; Risk; Sweden; Uncoupling Protein 2

Variation in the calpain-10 gene (CAPN10) has been associated with risk of type 2 diabetes in the Mexican American population of Starr County, Texas. We typed five polymorphisms in the calpain-10 gene (SNP-43, -43, -63, and -110 and Indel-19) to test for association with type 2 diabetes in 248 individuals representative of the mestizo population of Mexico City and Orizaba, Mexico including 134 patients with type 2 diabetes and 114 subjects with normal fasting blood glucose levels. We found a significant difference in SNP-44 allele and genotype frequencies between type 2 diabetic and non-diabetic subjects. The rare allele at SNP-44 was associated with increased risk of type 2 diabetes (odds ratio (OR)=2.72, 95% confidence interval (CI)=1.16-6.35, P=0.017). SNP-110, which is in perfect linkage disequilibrium with SNP-44, was also associated with type 2 diabetes. The SNP-43, Indel-19, and SNP-63 haplogenotype 112/121 associated with significantly increased risk (OR=2.16, 95% CI=1.31-3.57) of type 2 diabetes in Mexican Americans was not associated with significantly increased in risk in Mexicans (OR=1.15, 95% CI=0.57-2.34). The results suggest that variation in CAPN10 affects risk of type 2 diabetes in the mestizo population of central Mexico (Mexico City and Orizaba) and in Mexican Americans (Starr County, Texas).

Topics: Aged; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Haplotypes; Humans; Linkage Disequilibrium; Male; Mexico; Middle Aged; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Texas

Gestational diabetes mellitus (GDM) is a frequent complication of pregnancy. Epidemiologic and pathophysiologic data suggest a close link of this disease to non-insulin-dependent diabetes mellitus. Within the calpain-10 gene various single-nucleotide polymorphisms have been identified that increased the risk for non-insulin-dependent diabetes mellitus. Therefore, we examined single-nucleotide exchanges of this gene in women with GDM.. A total of 875 unselected women were prospectively screened for GDM. Eighty women of this population, 40 patients with an abnormal oral glucose tolerance test and 40 normal controls, were randomly selected. DNA samples isolated from sera of the control and study groups were analyzed with respect to single-nucleotide polymorphisms of the calpain-10 gene at positions 43, 19, and 63 using polymerase chain reaction amplification and restriction analysis.. Women with GDM were more likely to be homozygous for the allele 1 of single-nucleotide polymorphism 63 (P =.02 by chi(2) test). With respect to single-nucleotide polymorphisms 19 and 43, no significant differences in allele distribution were detected between controls and women with GDM. When comparing the different haplotypes for calpain-10 (single-nucleotide polymorphisms 43, 19, and 63), all women with the haplotype combination 121/221 (n = 8) had gestational diabetes (P =.005 by Fisher exact test).. Our results indicate that the haplotype 121/221 of the calpain-10 gene may be associated with disturbances of glucose metabolism during pregnancy.. II-1

Topics: Adult; Body Mass Index; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Diabetes, Gestational; Female; Glucose Tolerance Test; Haplotypes; Humans; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Pregnancy

The analysis of the haplotype-phenotype relationship has become more and more important. We have developed an algorithm, using individual genotypes at linked loci as well as their quantitative phenotypes, to estimate the parameters of the distribution of the phenotypes for subjects with and without a particular haplotype by an expectation-maximization (EM) algorithm. We assumed that the phenotype for a diplotype configuration follows a normal distribution. The algorithm simultaneously calculates the maximum likelihood (L0max) under the null hypothesis (i.e., nonassociation between the haplotype and phenotype), and the maximum likelihood (Lmax) under the alternative hypothesis (i.e., association between the haplotype and phenotype). Then we tested the association between the haplotype and the phenotype using a test statistic, -2 log(L0max/Lmax). The above algorithm along with some extensions for different modes of inheritance was implemented as a computer program, QTLHAPLO. Simulation studies using single-nucleotide polymorphism (SNP) genotypes have clarified that the estimation was very accurate when the linkage disequilibrium between linked loci was rather high. Empirical power using the simulated data was high enough. We applied QTLHAPLO for the analysis of the real data of the genotypes at the calpain 10 gene obtained from diabetic and control subjects in various laboratories.

Topics: Algorithms; Blood Glucose; Body Mass Index; Calpain; Computer Simulation; Diabetes Mellitus, Type 2; Haplotypes; Humans; Insulin; Likelihood Functions; Linkage Disequilibrium; Models, Genetic; Phenotype; Polymorphism, Single Nucleotide; Quantitative Trait, Heritable

In order to determine whether the variations in the calpain-10 gene constitutes risk of type 2 diabetes (T2DM) in Chinese, the frequency of UCSNP-43, 44 in 268 adults newly diagnosed with T2DM (according to the 1999 ADA criteria) and 153 non-diabetic control subjects was investigated. For all subjects, the height, weight, waist-to-hip ratio (W/H) and blood pressure, as well as following parameters were measured: (1) 75-g oral glucose tolerance test with insulin, C-peptide, HbA1c and blood lipid profiles; (2) Genomic DNA extracted from peripheral blood lymphocytes was genotyped for UCSNP-43 (calpain-10-g. 4852 G/A) and UCSNP-44 (calpain-10-g. 4841 T/C) by sequencing a polymerase chain reaction (PCR)-amplified fragment. PCR product was selected by single strand conformation polymorphism (SSCP) and then sequenced. The results showed that there was significant difference between T2DM group and normal control group in allele frequencies, haplotype frequencies, or haplotype combinations of UCSNP-43 and -44 either. But in newly diagnosed T2DM group, it was found that the individuals with the genotype UCSNP-44 T/C + C/C had significantly increased fasting and post-challenge insulin levels (Fins and P2hIns), consistent with reduced insulin sensitivity. In the BMI> 25 subgroup, the differences were even more significant. It was demonstrated that the Calpain-10 gene polymorphism UCSNP-44 was associated with insulin sensitivity and Fins and P2hIns in newly diagnosed T2DM, although Calpain-10 doesn't appear as a major diabetes susceptible gene in this population.

Topics: Adult; Asian People; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Humans; Insulin Resistance; Male; Middle Aged; Phenotype; Point Mutation; Polymorphism, Genetic

The 112/121 haplotype combination defined by the UCSNP-43, -19, and -63 alleles in the calpain-10 gene is associated with type 2 diabetes in Mexican Americans. To determine whether this genetic variation constitutes risk of type 2 diabetes in Japanese, we investigated its frequency in 177 patients with type 2 diabetes and 172 controls. Though this variation occurs in Japanese more frequently than in Mexican Americans, there is no significant difference in frequency between diabetic (29.9%) and control (31.9%) subjects. We also screened all exons and the putative promoter of the calpain-10 gene for mutations in 96 of the genotyped patients, resulting in the identification of 7 coding variants, including 3 missense mutations and 5 nucleotide alterations in the promoter. However, their frequencies all are similar in patients and controls, suggesting that these genetic variations are not a major factor in the occurrence of type 2 diabetes in Japanese, although they could yet be associated with various phenotypes of the disease.

Topics: Aged; Asian People; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Genetic Testing; Genetic Variation; Glucose Clamp Technique; Haplotypes; Humans; Japan; Male; Mexican Americans; Middle Aged; Polymorphism, Genetic; Promoter Regions, Genetic

Topics: Calpain; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Reagent Kits, Diagnostic

Biallelic markers, such as single nucleotide polymorphisms (SNPs), provide greater information for localising disease loci when treated as multilocus haplotypes, but often haplotypes are not immediately available from multilocus genotypes in case-control studies. An artificial neural network allows investigation of association between disease phenotype and tightly linked markers without requiring haplotype phase and without modelling any evolutionary history for the disease-related haplotypes. The network assesses whether marker haplotypes differ between cases and controls to the extent that classification of disease status based on multi-marker genotypes is achievable. The network is "trained" to "recognise" affection status based on supplied marker genotypes, and then for each multi-marker genotype it produces outputs which aim to approximate the associated affection status. Next, the genotypes are permuted relative to affection status to produce many random datasets and the process of training and recording of outputs is repeated. The extent to which the ability to predict affection for the real dataset exceeds that for the random datasets measures the statistical significance of the association between multi-marker genotype and affection. This permutation test performs well with simulated case-control datasets, particularly when major gene effects are present. We have explored the effects of systematically varying different network parameters in order to identify their optimal values. We have applied the permutation test to 4 SNPs of the calpain 10 (CAPN10) gene typed in a case-control sample of subjects with type 2 diabetes, impaired glucose tolerance, and controls. We show that the neural network produces more highly significant evidence for association than do single marker tests corrected for the number of markers genotyped. The use of a permutation test could potentially allow conditional analyses which could incorporate known risk factors alongside marker genotypes. Permuting only the marker genotypes relative to affection status and these risk factors would allow the contribution of the markers to disease risk to be independently assessed.

Topics: Calpain; Case-Control Studies; Computer Simulation; Diabetes Mellitus, Type 2; Genetic Testing; Genotype; Haplotypes; Humans; India; Neural Networks, Computer; Polymorphism, Genetic

An association of variations in the calpain-10 gene (CAPN10) with type 2 diabetes was originally reported in Mexican Americans. However, some studies in other racial groups were contradictory.. We studied the influence of genotypes and haplotype combinations (haplogenotypes) of CAPN10 on the metabolic traits in 286 Japanese subjects who visited a General Health Check-up Center.. As for single nucleotide polymorphism (SNP)-19, subjects with genotype 22 had higher body mass index (BMI) and hemoglobin A(1c) (HbA(1c)) levels than those with genotypes 11 and 12 (p=0.003 and p=0.024, respectively). In SNP-63, subjects with genotype 11 had higher BMI and HbA(1c) levels than those with genotypes 12 and 22 (p=0.003 and p=0.045, respectively). Subjects who had genotype 22 at SNP-19 always had genotype 11 at SNP-63. Subjects with haplogenotype 121/121 had higher BMI levels (p=0.021) and tended to have higher HbA(1c) levels (p=0.08) than those with other haplogenotypes. All things considered, SNP-19 genotype 22, which was composed of haplogenotype 121/121 and 121/221, had highest significance level of association with elevated HbA(1c) levels. SNP-43 did not affect metabolic traits in our subjects. Subjects with haplogenotype 112/121 rather showed lower BMI and HbA(1c) levels (p=0.016 and p=0.008) than those with all other haplogenotypes.. These results indicate the contribution of SNP-19 in CAPN10 to mild obesity and glucose intolerance in Japanese.

Topics: Blood Glucose; Body Mass Index; Calpain; Cholesterol; Diabetes Mellitus, Type 2; Fasting; Female; Gene Frequency; Glycated Hemoglobin; Haplotypes; Humans; Japan; Male; Middle Aged; Polymorphism, Single Nucleotide; Statistics, Nonparametric; Triglycerides

To detect the Calpain10 gene polymorphisms in North China families with type 2 diabetes and to investigate their association with type 2 diabetes.. PCR-RFLP method was used to test the polymorphisms of Calpain10 SNP43 (G/A) and SNP19 (1/2) in 801 individuals from 218 type 2 diabetes mellitus (DM) families, 211 type 2 diabetes patients without family history, and 127 normal control subjects in northern China.. (1) The Calpain 10 SNP43 "G" allele frequency was 91.9% in the type 2 diabetic patients without family history, 92.7% in the probands from the type 2 diabetes families without linkage between the onset of DM and SNP43 site, and 95.3% in the probands from type 2 diabetes families with linkage evidence at SNP43, all significantly higher than that in the controls (85.8%, chi(2) = 6.39, df = 1,P = 0.011; chi(2) = 8.437,df = 1, P < 0.01); and chi(2) = 16.49, df = 1, P < 0.01). The distribution of polymorphism of the SNP19 site was not significantly different between the patients and control subjects. (2) Logistic regression analysis adjusted by BMI, sex and age showed that SNP43 G/G genotype was associated with type 2 diabetes. The odds ratios of the three group were OR = 1.78, P = 0.045; OR = 2.53, P = 0.008; OR = 4.32, P = 0.000 respectively.. SNP43 site of Calpain10 gene is related to type 2 diabetes. Calpain 10 gene may be a related gene of type 2 diabetes in Chinese.

Topics: Adult; Aged; Calpain; Diabetes Mellitus, Type 2; Female; Genetic Linkage; Genotype; Humans; Male; Middle Aged; Polymorphism, Genetic; Polymorphism, Single Nucleotide

The mRNA expression of type 2 diabetes-related genes in white blood cells (WBC) was examined before and after onset in Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The level of the calpain 10 (CAPN10) transcript was significantly decreased compared to control animals in WBC before and after onset. Significant decreases in this gene expression were also found in the major insulin-target tissues as well as WBC before onset. These results suggest that gene expression in WBC could be a useful screening system for predicting the incidence of type 2 diabetes before onset in OLETF rats, and that CAPN10 represents a potential candidate gene for predicting type 2 diabetes in human.

Topics: Adipose Tissue; Age of Onset; Animals; Blood Glucose; Body Weight; Calpain; Diabetes Mellitus, Type 2; Down-Regulation; Gene Expression; Genetic Testing; Humans; Leukocytes; Liver; Male; Muscles; Rats; Rats, Inbred OLETF; Rats, Long-Evans; RNA, Messenger; Time Factors

The rat strain Otsuka Long-Evans Tokushima Fatty (OLETF) is an animal model for type 2 diabetes mellitus. Nidd8/of has been identified as one of 14 quantitative trait loci (QTLs) involved in the diabetes by a whole genome search in 160 F2 progenies obtained by mating the OLETF and F344 rats. Comparative mapping between human and rat indicated that the Nidd8/of genomic region, near D9rat21 on rat chromosome 9, contains the calpain10 (Capn10) gene, which is putative type 2 diabetes-susceptibility gene in humans. In this study, we found no difference in Capn10 mRNA expression in the heart, liver, skeletal muscle and pancreas between OLETF and F344 rats at 5 and 10 weeks of age. However, we found a single nucleotide polymorphism (SNP) (A/A genotype in OLETF and G/G genotype in F344 and LETO rats) at the base 583 downstream from the translation start site in the rat Capn10 cDNA sequence. This SNP was deduced to substitute serine (OLETF) for glycine (F344 and LETO) at the 195 amino acid residue within the protease domain of rat Capn10. Because serine is generally not interchangeable with glycine in respect of the protein structure and function, it was deduced that the A/A genotype in OLETF is not a 'safe' mutation. This non-conservative amino acid substitution might be associated with susceptibility to type 2 diabetes in OLETF rats.

Topics: Animals; Calpain; Diabetes Mellitus, Type 2; Disease Models, Animal; Genetic Predisposition to Disease; Mutation; Organ Specificity; Rats; Rats, Inbred OLETF

To study the contribution of single nucleotide polymorphism-UCSNP44 at calpain-10 gene (CAPN-10) on NIDDM1 locus to type 2 diabetes mellitus (T2DM) in Chinese.. 276 Chinese living in Shanghai, 148 with normal glucose tolerance (NGT) and 128 with T2DM were given 75 g glucose. O, 30, 60, 120, and 180 minutes later their plasma glucose (PG), insulin (INS), C-peptide (CP), and free fatty acids (FFA) were measured and the areas under curve (AUC) were calculated. The islet beta-cell insulin secretion and tissue insulin sensitivity were estimated by formulae of homeostasis model assessment and increment ratio of insulin to glucose levels 30 minutes after glucose challenge. The CAPN-10 UCSNP44 as well as UCSNP43 were genotyped by automated DNA direct sequencing.. (1) The major genotype of CAPN-10 UCSNP44 in persons with NGT was TT (with a frequency of 0.82); the major allele was T (0.91). The most frequent genotype combination between UCSNP44 and UCSNP43 was TT-GG (corresponding to haplotype combination TG/TG) (0.64). The most frequent haplotype was TG (0.80). The D value for linkage disequilibrium between UCSNP44 and UCSNP43 was -0.11. (2) The frequencies of UCSNP44 and UCSNP44/UCSNP43 haplotype combination did not differ significantly between subjects with NGT and those with T2DM. (3) The PG levels in T2DM subjects with UCSNP44 TT genotype both at fasting and after glucose challenge were statistically significantly higher than those in subjects with non-TT (TC + CC) genotype, especially the PG levels 0, 60, 120, and 180 minutes after glucose challenge (P = 0.036, 0.040, 0.020, and 0.017) and the PG-AUC (P = 0.013). The PG levels and PG-AUC 0 and 120 minutes after glucose challenge were still significant after adjusted with age, sex, and body mass index and waist circumference. Similar results were observed in comparison between the TG/TG and TG/CG subgroups of UCSNP44/UCSNP43 haplotype combination. In addition, T2DM subjects with UCSNP44 TT genotype had lower CP levels after glucose challenge than those with non-TT genotype. However, the difference became not statistically significant after adjusted with above-mentioned variables.. The variation of CAPN-10 UCSNP44 has an impact on plasma glucose levels at fasting and after glucose challenge in subjects with type 2 diabetes. The relevant mechanism remains to be elucidated.

Topics: Blood Glucose; Calpain; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Polymorphism, Single Nucleotide

Topics: Arizona; Birth Weight; Calpain; Carrier Proteins; Diabetes Mellitus, Type 2; Fatty Acid-Binding Protein 7; Fatty Acid-Binding Proteins; Humans; Indians, North American; Insulin Resistance; Linkage Disequilibrium; Neoplasm Proteins; Phosphoprotein Phosphatases; Polymorphism, Genetic; Tumor Suppressor Proteins

Variations in the calpain-10 gene (CAPN10) have been identified among Mexican-Americans, and an at-risk haplotype combination (112/121) defined by three polymorphisms, UCSNP-43, -19, and -63, confers increased risk of type 2 diabetes. Here we examine the three polymorphisms in 1,594 Scandinavian subjects, including 409 type 2 diabetic patients, 200 glucose-tolerant control subjects, 322 young healthy subjects, 206 glucose-tolerant offspring of diabetic patients, and 457 glucose-tolerant 70-year-old men. The frequency of the 112/121 combination was not significantly different in 409 type 2 diabetic subjects compared with 200 glucose-tolerant control subjects (0.06 vs. 0.05; odds ratio 1.32 [95% CI 0.58-3.30]). In glucose-tolerant subjects, neither the single-nucleotide polymorphisms individually nor the 112/121 combination were associated with alterations in plasma glucose, serum insulin, or serum C-peptide levels at fasting or during an oral glucose tolerance test, estimates of insulin sensitivity, or glucose-induced insulin secretion. In conclusion, the frequency of the 112/121 at-risk haplotype of CAPN10 is low among Scandinavians and we were unable to demonstrate significant associations between the CAPN10 variants and type 2 diabetes, insulin resistance, or impaired insulin secretion.

Topics: Adult; Aged; Aged, 80 and over; Calpain; Chromosomes, Human, Pair 2; Cohort Studies; Control Groups; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genetic Variation; Glucose; Haplotypes; Humans; Insulin; Insulin Resistance; Insulin Secretion; Male; Middle Aged; Phenotype; Polymorphism, Genetic; Scandinavian and Nordic Countries; White People

Recently, an A-to-G variant in intron 3 (SNP43) of the calcium-activated neutral protease 10 gene (CAPN10) was identified as a possible type 2 diabetes susceptibility gene through positional cloning in Mexican-Americans. We conducted cross-sectional and prospective studies to evaluate the relation between SNP43 and type 2 diabetes and related traits in middle-aged African-American participants of the Atherosclerosis Risk in Communities Study, a population-based longitudinal study. At baseline, 269 prevalent diabetes cases and 1,159 nondiabetic control subjects were studied. Those with the G/G genotype were more likely to have diabetes than those with the A/G or A/A genotype (odds ratio [OR] 1.41, 95% CI 1.00-1.99, P = 0.05). In the prospective study, 166 of the control subjects developed incident diabetes over 9 years of follow-up. The incidence of diabetes for individuals with the G/G genotype did not differ significantly from those with at least one copy of the A allele (23.3 vs. 19.5 per 1,000 person years, P = 0.29). Pooling prevalent and incident diabetic cases together, individuals with the G/G genotype were approximately 40% more likely to have diabetes than those without (OR 1.38, 95% CI 1.04-1.83, P = 0.03). Because of the high frequency of the G allele (0.88), approximately 25% of the susceptibility to type 2 diabetes in African-Americans may be attributed to the G/G genotype at SNP43 of CAPN10, although most of the subjects with the G/G genotype did not develop diabetes over the 9 years of follow-up. We conclude from this large prospective study that the G allele of SNP43 of CAPN10 or another allele or gene that is in linkage disequilibrium with it increases susceptibility to type 2 diabetes in African-Americans.

Topics: Arteriosclerosis; Black People; Blood Glucose; Blood Pressure; Calpain; Cholesterol, HDL; Cholesterol, LDL; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Genetic Variation; Genotype; Humans; Incidence; Insulin; Introns; Male; Middle Aged; Prediabetic State; Prevalence; Risk Factors; Socioeconomic Factors; Triglycerides; United States

Non-insulin-dependent diabetes mellitus (NIDDM) is characterized by the presence of abnormally active platelets in the circulation, leading to increased incidence of thrombotic complications. In this study, we have attempted to understand the pathophysiology of the platelets in NIDDM.. Platelet aggregation was induced by thrombin receptor-activating peptide or epinephrine. Membrane fluidity was derived from the steady-state fluorescence anisotropy of diphenylhexatriene incorporated in the membrane. The phosphotyrosine content of the platelet proteins was probed using specific monoclonal antibodies. The extent of calpain activity was assessed from the proteolysis of calpain substrates.. Aggregation was significantly enhanced (p<0.001) in the platelets obtained from the cases of NIDDM. Anisotropy measurements reflected a significant increase in the microviscosity of platelet membranes from 3.315 (+/-0.103) in the control to 4.153 (+/-0.119) in NIDDM. Proteins of relative mobilities of 131, 100, 47 and 38 kDa were found to remain phosphorylated on tyrosine in the resting platelets obtained from NIDDM patients, while they were not phosphorylated in the control counterparts. This was associated with heightened activity of the calcium-dependent thiol protease, calpain, in NIDDM.. Taken together, these data indicated significant changes in the signaling mechanism in the platelets obtained from NIDDM, which could lead to platelet hyperactivity in this disease.

Topics: Adult; Blood Platelets; Calcimycin; Calpain; Case-Control Studies; Cell Membrane; Diabetes Mellitus, Type 2; Epinephrine; Humans; Middle Aged; Phosphorylation; Pilot Projects; Platelet Activation; Platelet Aggregation; Reference Values; Signal Transduction; Tyrosine

The calpain-10 gene (CAPN10) has been implicated in type 2 diabetes (T2DM) susceptibility by both linkage and association in a Hispanic population from Starr County Texas. Common intronic variants seem to alter CAPN10 mRNA levels and were associated with insulin resistance but not diabetes in Pima Indians. The role of these variants in Caucasian populations is less clear. We found some evidence for linkage of T2DM to chromosome 2q approximately 20 cM proximal to the NIDDM1/CAPN10 locus. To test the hypothesis that CAPN10 is a diabetes susceptibility locus in Caucasian families at high risk for T2DM, we examined the influence of the three previously implicated CAPN10 variants on both diabetes risk and measures of insulin sensitivity and glucose homeostasis. We genotyped approximately 700 members of 63 families for 3 variants (SNP-43, SNP-19, and SNP-63). We tested each variant separately and as haplotype combinations for altered transmission from parents to affected children (transmission disequilibrium test), and we tested for an effect of each variant individually on measures of glucose and insulin during a glucose tolerance test in nondiabetic family members. Finally, we looked for an effect of each variant on measures of insulin sensitivity (S(I)) and insulin secretion estimated by frequently sampled iv glucose tolerance test and Minimal Model analysis. We could not confirm an increase in risk for T2DM susceptibility for any variant or for any haplotype combination, although we found marginal evidence for an increased risk of the 111/221 haplotype combination (P = 0.036) after ascertainment correction. However, both SNP-19 and SNP-63 increased fasting and/or postchallenge insulin levels, consistent with reduced insulin sensitivity. Furthermore, SNP-19 had modest effects on insulin sensitivity measured by homeostatic model, and on postchallenge glucose. The reduction in insulin sensitivity was confirmed by analysis of the subset of individuals who underwent iv glucose tolerance tests, where SNP-19 significantly altered the insulin sensitivity index. CAPN10 cannot be considered a major diabetes susceptibility gene in our population and seems unlikely to explain the observed linkage findings. However, CAPN10 influences insulin sensitivity and glucose homeostasis in nondiabetic members of kindreds at high risk for T2DM.

Topics: Alleles; Blood Glucose; Calpain; Chromosome Mapping; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Gene Frequency; Genetic Linkage; Genetic Predisposition to Disease; Genetic Variation; Genotype; Glucose Tolerance Test; Haplotypes; Homeostasis; Humans; Insulin; Insulin Resistance; Insulin Secretion; White People

A G-to-A (UCSNP-43) polymorphism of the calpain-10 gene was significantly associated with type 2 diabetes (DM) in Mexican-American, and was postulated, together with a T-to-C (UCSNP-44) polymorphism, as a risk factor for DM. We examined the association of these genotypes with DM in Japanese. Eighty-one subjects with DM and 81 non-diabetic subjects (NGT) were recruited. The number of subjects with genotypes UCSNP-43 G/G, G/A and A/A were 76, 5 and 0, respectively, for the DM and NGT groups. The number of subjects with genotypes UCSNP-44 T/T, T/C and C/C were 66, 14 and 1 for the DM group and 64, 17 and 0 for the NGT group. There was no difference between the groups in terms of frequency of any genotype combinations. No association between the genotypes and DM was observed. We next examined the differences between the genotypes or genotype combinations in terms of the traits related to DM, obesity, hypertension and dyslipidemia. No differences were observed between the genotypes UCSNP43 G/G and G/A, between UCSNP-44 T/T and the others, or between the genotype combination UCSNP-43 G/G and UCSNP-44 T/T and the others, except that the individuals with the genotype combination had significantly increased serum cholesterol levels (212.6 +/- 34.3 vs. 198.5 +/- 29.9, P=0.020). The genotype combination might be a risk factor, not for DM, obesity and hypertension, but for increased serum cholesterol.

Topics: Aged; Asian People; Calpain; Cholesterol; Diabetes Mellitus, Type 2; Female; Glucose Intolerance; Humans; Hypercholesterolemia; Japan; Male; Middle Aged; Polymerase Chain Reaction; Polymorphism, Genetic; Polymorphism, Restriction Fragment Length

Recently, a positional cloning study proposed that haplotypes at the calpain-10 locus (CAPN10) are associated with increased risk of type 2 diabetes, or non-insulin-dependent diabetes mellitus, in Mexican Americans, Finns, and Germans. To inform the interpretation of the original mapping results and to look for evidence for the action of natural selection on CAPN10, we undertook a population-based genotyping survey of the candidate susceptibility variants. First, we genotyped sites 43, 19, and 63 (the haplotype-defining variants previously proposed) and four closely linked SNPs, in 561 individuals from 11 populations from five continents, and we examined the linkage disequilibrium among them. We then examined the ancestral state of these sites by sequencing orthologous portions of CAPN10 in chimpanzee and orangutan (the identity of sites 43 and 19 was further investigated in a limited sample of other great apes and Old World and New World monkeys). Our survey suggests larger-than-expected differences in the distribution of CAPN10 susceptibility variants between African and non-African populations, with common, derived haplotypes in European and Asian samples (including one of two proposed risk haplotypes) being rare or absent in African samples. These results suggest a history of positive natural selection at the locus, resulting in significant geographic differences in polymorphism frequencies. The relationship of these differences to disease risk is discussed.

Topics: Africa; Alleles; Animals; Calpain; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Gene Frequency; Genetic Predisposition to Disease; Genetic Variation; Haplorhini; Haplotypes; Humans; Linkage Disequilibrium; Polymorphism, Single Nucleotide; Racial Groups; Selection, Genetic

Polycystic ovary syndrome (PCOS) is associated with an increased risk of impaired glucose tolerance and type 2 diabetes. Recent evidence suggests that variation in the gene encoding the cysteine protease calpain-10 influences susceptibility to type 2 diabetes. The present study was undertaken to determine whether variation in this gene is associated with quantitative traits pertinent to the pathogenesis of PCOS and diabetes. We studied 212 women with PCOS (124 white of European ancestry, 57 African-American, 13 Hispanic, 13 Asian-American, and 5 Middle-Eastern). Each subject was genotyped for 3 DNA polymorphisms in the calpain-10 gene associated with type 2 diabetes (SNP-43, -19, and -63). The white and African-American subjects were examined for association of these polymorphisms with phenotypic features of PCOS and type 2 diabetes. There were not enough individuals in the other groups for similar genotype/phenotype analyses. Nineteen (9%) of the 212 women with PCOS were diabetic and were not included in the genotype/phenotype analyses. Twelve (63%) of these subjects were African-American. Phenotypic traits in nondiabetic white probands did not differ whether analyzed for each individual SNP (SNP-43, -19, -63) or haplotype combination. Nor was there association of SNP-43, -19, or -63 with any of the phenotypic features of type 2 diabetes or PCOS in nondiabetic African-Americans. However, nondiabetic African-Americans with the 112/121-haplotype combination had significantly higher insulin levels, in response to an oral glucose challenge, as reflected in the area under the insulin curve (257,021 +/- 95,384 vs. 136,240 +/- 11,468 pmol/min; P = 0.03), compared with those with other haplotypes. This finding was particularly notable because the 112/121 subjects were less obese. The difference between groups in area under the insulin response curve remained significant (P = 0.002 by analysis of covariance) after adjustment for body mass index. In addition to its association with insulin levels in African-Americans, the 112/121-haplotype combination was associated with an approximate 2-fold increase in risk of PCOS in both African-Americans and whites.

Topics: Administration, Oral; Adult; Black or African American; Black People; Calpain; Diabetes Mellitus, Type 2; DNA; Female; Genetic Predisposition to Disease; Genotype; Glucose; Haplotypes; Humans; Insulin; Phenotype; Polycystic Ovary Syndrome; Polymorphism, Genetic; Quantitative Trait, Heritable

Haplotype combination 112/121 and its intrinsic variants (UCSNP43, -19, and -63) identified within the calpain 10 gene are associated with increased risk of type 2 diabetes in Mexican-Americans. We evaluated whether this haplotype combination and its constituent haplotypes and variants contribute to increased susceptibility to impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) and type 2 diabetes in a South Indian population. Two study groups were used: 95 families ascertained through a proband with type 2 diabetes and 468 subjects recruited as part of an urban survey (69.1% with normal glucose tolerance, 12.8% with IFG/IGT, and 18.2% with type 2 diabetes). The four-locus haplotype combination 1112/1121 (UCSNP44, -43, -19, and -63) in South Indians conferred both a 10.7-fold increased risk for IFG/IGT (P = 0.001) and a 5.78- to 6.52-fold increased risk for type 2 diabetes in the two study groups (families P = 0.025, urban survey P = 0.015). A combination of the 1112 haplotype with the 1221 haplotype also appeared to increase risk for both IFG/IGT and type 2 diabetes. Contrary to what might be expected, quantitative trait analysis in the families found that transmission of the disease-related 1121 and 1112 haplotypes was associated with a reduced hip size and lower waist-to-hip ratio, respectively. This study supports the paradigm that specific haplotype combinations of calpain 10 variants increase risk of both IFG/IGT and type 2 diabetes. However, the relative infrequency of the "at-risk" combinations in the South Indian population suggests that calpain 10 is not a common determinant of susceptibility to type 2 diabetes.

Topics: Adult; Aged; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Indians, North American; Male; Mexican Americans; Middle Aged; Polymorphism, Genetic; Quantitative Trait, Heritable; Risk Factors; Urban Population

Variations in the calpain-10 gene have recently been reported to be associated with type 2 diabetes in a Mexican-American population. We typed three single nucleotide polymorphisms (SNPs) in the calpain-10 gene (SNPs 43, 56, and 63) to test for association between variation at these loci and type 2 diabetes and diabetes-related traits in 1,603 Finnish subjects: two samples of 526 (Finland-U.S. Investigation of NIDDM Genetics [FUSION] 1) and 255 (FUSION 2) index case subjects with type 2 diabetes, 185 and 414 unaffected spouses and offspring of FUSION 1 index case subjects or their affected siblings, and 223 elderly normal glucose-tolerant control subjects. We found no significant differences in allele, genotype, haplotype, or haplogenotype frequencies between index case subjects with diabetes and the elderly and spouse control populations (all P > 0.087). Although variation in these three SNPs was associated with variation in some type 2 diabetes-related traits within each of the case and control groups, no consistent pattern of the implicated variant or combination of variants was discerned. We conclude that variation in these three SNPs in the calpain-10 gene is unlikely to confer susceptibility to type 2 diabetes in this Finnish cohort.

Topics: Aged; Calpain; Cohort Studies; Diabetes Mellitus, Type 2; Female; Finland; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Male; Middle Aged; Phenotype; Polymorphism, Single Nucleotide; Risk Factors

The polymorphisms of two genes have recently been associated with complex forms of type 2 diabetes mellitus (T2DM): calpain 10 and peroxisome proliferator-activated receptor-gamma (PPARgamma). Calpain 10 is a member of a large family of intracellular proteases. It was shown in Mexican-Americans and other populations that variants of three single nucleotide polymorphisms (SNPs), -43, -19, and -63, of this ubiquitously expressed protein influence susceptibility to T2DM. However, substantial differences were shown between ethnic groups in at risk alleles and haplotypes as well as in their attributable risk. Thus, it is important to determine the role of calpain 10 in various populations.. To examine the role of calpain 10 SNPs -43, -19, and -63 in genetic susceptibility to T2DM in a Polish population.. Overall, 377 individuals were examined: 229 T2DM patients and 148 control individuals. The groups were genotyped for calpain 10 SNP-43, SNP-19, and SNP-63. SNP-19 was examined by electrophoresis of the PCR product on agarose gel by size, while the restriction fragment length polymorphism (RFLP) method was used for the two other markers. Differences in allele, genotype, haplotype, and haplotype combination distribution between the groups were examined by chi(2) test.. Distributions of alleles, genotypes, and haplotypes at three loci defined by examined SNPs were not significantly different between the groups. However, the homozygote combination of 121 haplotype was more prevalent in the T2DM group than in the controls (17.9% vs 10.1%, P=0.039). No difference was observed in the 112/121 haplotype distribution. This heterozygous haplotype combination was associated with increased risk of T2DM in several populations.. The results of our study suggest the association of calpain 10 121/121 haplotype combination created by SNPs -43, -19, and -63 with T2DM in a Polish population. However, we were not able to confirm the previously described role of the heterozygous 112/121 haplotype combination in susceptibility to T2DM.

Topics: Adult; Aged; Calpain; Diabetes Mellitus, Type 2; Female; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Homozygote; Humans; Male; Middle Aged; Poland; Polymorphism, Genetic; Reference Values

To investigate the distribution of single nucleotide polymorphisms (SNPs) in CAPN10 gene in Chinese population and their relation with type 2 diabetes mellitus in Han people of Northern China.. CAPN10 gene was sequenced to detect SNPs in different nationalities of China. Five SNPs were chosen to perform case-control study and haplotype analysis in 156 normal Han people of Northern China and 173 type 2 diabetes. One SNP was also analyzed with transmission-disequilibrium test (TDT) and sib transmission-disequilibrium test (STDT) in 68 type 2 diabetes pedigrees (377 people).. A total of 40 SNPs were identified in length of 8,936 bp, with an average of 1 in every 223 bp. The SNPs in CAPN10 gene did not distribute evenly and the SNPs in Chinese were different from those reported in Mexican American. There was no significantly statistical difference in the allele frequency of the 5 SNPs between case and control, and the haplotype frequencies in the two groups were not significantly different. No positive results was found in TDT and STDT analysis.. The SNP distribution of CAPN10 gene differs in different nationalities. The studied SNPs in CAPN10 gene may not be the major susceptibility ones of type 2 diabetes mellitus in Han people of Northern China.

Topics: Calpain; Case-Control Studies; China; Diabetes Mellitus, Type 2; Ethnicity; Genetic Predisposition to Disease; Humans; Polymerase Chain Reaction; Polymorphism, Single Nucleotide

Variation within the calpain-10 gene (CAPN10) has been proposed to account for linkage to type 2 diabetes on chromosome 2q in Mexican-Americans, and associations with diabetes have been reported in several other populations. Given the epidemiological, physiological, and genetic overlap between type 2 diabetes and polycystic ovary syndrome (PCOS), CAPN10 represents a strong candidate gene for a role in PCOS susceptibility. Using both family based and case-control association resources (146 parent-offspring trios; 185 additional PCOS cases; 525 control subjects, all of European ancestry), we sought association between CAPN10 variation and PCOS, focusing on four single nucleotide polymorphism (SNP) variants (SNP-44, SNP-43; SNP-19; SNP-63). On single-locus transmission disequilibrium analysis in the 146 trios, there was nominal evidence (P = 0.03) of excess transmission of the more common allele at SNP-63. This association was not, however, replicated in the case-control analysis. No other significant associations were observed at the single-locus or haplotype level in either the transmission-disequilibrium or case-control analyses. The relative risk for the high-risk diabetes susceptibility 112/121 genotype (SNPs 43-19-63) was 0.84 (95% confidence intervals, 0.40-1.71). No associations were seen with intermediate traits of relevance to diabetes and PCOS pathogenesis. We have found no evidence from these analyses that CAPN10 gene variation influences susceptibility to PCOS.

Topics: Adult; Calpain; Case-Control Studies; Chromosome Mapping; Diabetes Mellitus, Type 2; Female; Genetic Predisposition to Disease; Genetic Variation; Humans; Polycystic Ovary Syndrome; Quantitative Trait, Heritable

In light of evidence of linkage of obesity to chromosome 2q31-q37, we hypothesized that the calpain-10 gene 'high-risk' haplotype combination for non-insulin-dependent diabetes mellitus (NIDDM) is involved in early onset obesity. We screened the NIDDM 'high-risk'-haplotype combination formed by the alleles 112 and 121 of the polymorphisms UCSNP-43, -19, and -63 in 166 families consisting of an extremely obese child or adolescent (mean BMI percentile: 99.3+/-1.38), one or more obese sibs (mean BMI percentile: 97.42+/-2.88), and both of their parents. Genotyping for three calpain-10 gene polymorphisms was performed by polymerase chain reaction (PCR) with (a) length polymorphism detection (UCSNP-19) or (b) allele-specific PCR (UCSNP-43 and -63). To allow for correct haplotype assignment all individuals were additionally genotyped for two microsatellite markers (D2S125 and D2S2338). We followed a hierarchical test procedure. As the first step, model-free linkage analysis was performed using maximum likelihood binomial statistics. The second stage consisted of a one-sided asymptotic pedigree disequilibrium test for the UCSNP-43 and on an exploratory level for the other SNP-markers and all haplotypes formed by the three SNPs. The final stage investigated the reported haplotype combination. We failed to detect an initial linkage of obesity to this region (LOD score <0.4). All subsequent exploratory analyses were negative. Our analysis of the relationship between the NIDDM 'high-risk' haplotype combination and extreme early onset obesity revealed no evidence for linkage and association.

Topics: Adolescent; Age of Onset; Alleles; Calpain; Child; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Female; Haplotypes; Humans; Linkage Disequilibrium; Male; Obesity; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Risk Factors

Topics: Alleles; Animals; Calpain; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Genetic Predisposition to Disease; Homozygote; Humans; Mice; Mice, Knockout; Mice, Transgenic; Polymorphism, Single Nucleotide

Topics: Amino Acid Substitution; Calpain; Diabetes Mellitus, Type 2; Female; Genes, Recessive; Heterozygote; Humans; Indians, North American; Male; Membrane Glycoproteins; Ontario; Phosphoric Diester Hydrolases; Point Mutation; Polymorphism, Genetic; Pyrophosphatases; Reference Values; Risk

Variation in CAPN10, the gene encoding the ubiquitously expressed cysteine protease calpain-10, has been associated with type 2 diabetes in Mexican Americans and in two northern-European populations, from Finland and Germany. We have studied CAPN10 in white subjects of British/Irish ancestry, using both family-based and case-control studies. In 743 sib pairs, there was no evidence of linkage at the CAPN10 locus, which thereby excluded it as a diabetes-susceptibility gene, with an overall sib recurrence risk, lambda(S), of 1.25. We examined four single-nucleotide polymorphisms (SNP-44, -43, -19, and -63) previously either associated with type 2 diabetes or implicated in transcriptional regulation of calpain-10 expression. We did not find any association between SNP-43, -19, and -63, either individually or as part of the previously described risk haplotypes. We did, however, observe significantly increased (P=.033) transmission of the less common C allele at SNP-44, to affected offspring in parents-offspring trios (odds ratio 1.6). An independent U.K. case-control study and a small discordant-sib study did not show significant association individually. In a combined analysis of all U.K. studies (P=.015) and in combination with a Mexican American study (P=.004), the C allele at SNP-44 is associated with type 2 diabetes. Sequencing of the coding region of CAPN10 in a group of U.K. subjects revealed four coding polymorphisms-L34V, T504A, R555C, and V666I. The T504A polymorphism was in perfect linkage disequilibrium with the diabetes-associated C allele at SNP-44, suggesting that the synthesis of a mutant protein and/or altered transcriptional regulation could contribute to diabetes risk. In conclusion, we were not able to replicate the association of the specific calpain-10 alleles identified by Horikawa et al. but suggest that other alleles at this locus may increase type 2 diabetes risk in the U.K. population.

Topics: Alleles; Calpain; Case-Control Studies; Diabetes Mellitus, Type 2; Genetic Linkage; Genotype; Haplotypes; Humans; Molecular Sequence Data; United Kingdom; White People

Although genomewide scans have identified several potential chromosomal susceptibility regions in several human populations, finding a causative gene for type 2 diabetes has remained elusive. Others have reported a novel gene, calpain-10 (CAPN10), located in a previously identified region on chromosome 2q37.3, as a putative susceptibility gene for type 2 diabetes. Three single-nucleotide polymorphisms (SNPs) (UCSNP43, UCSNP19, and UCSNP63) were shown to be involved in increased risk of the disease among Mexican Americans. We have tested the association of these three SNPs with type 2 diabetes among the Samoans of Polynesia, who have a very high prevalence of the disease. In the U.S. territory of American Samoa, prevalence is 25% and 15% in men and women, respectively, whereas, in the independent nation of Samoa, prevalence is 3% and 5% in men and women, respectively. In our study sample, which consisted of 172 unrelated affected case subjects and 96 control subjects, we failed to detect any association between case subjects and control subjects in allele frequencies, haplotype frequencies, or haplotype combinations of UCSNP43, -19, and -63. Also, our data showed no evidence of linkage, among 201 affected sib pairs, in the region of chromosome 2 that contains these SNPs. Three plausible scenarios could explain these observations. (1) CAPN10 is a susceptibility gene only in particular ethnic groups; (2) our study lacks power to detect the effects of CAPN10 polymorphisms (but our sample size is comparable to that of earlier reports); or (3) the underlying biological mechanism is too complex and requires further research.

Topics: Adult; Aged; Aged, 80 and over; Calpain; Chromosome Mapping; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Ethnicity; Female; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Linkage Disequilibrium; Lod Score; Male; Middle Aged; Polymorphism, Single Nucleotide; Prevalence; Samoa; Sample Size

To investigate the impact of calpain-10 gene (CAPN-10) combined single nucleotide polymorphism (SNP) variation on type 2 diabetes mellitus (T2DM) and its related clinical metabolic traits in Chinese.. The study population consisted of 268 Chinese residents in Shanghai. Among them, 144 were subjects with normal glucose tolerance (NGT) and 124, with T2DM. Plasma glucose (PG), insulin (INS), c-peptide (CP) and free fatty acids (FFA) levels were measured at fasting and 30, 60, 120, and 180 minutes after oral 75 g glucose challenge. The islet beta-cell insulin secretion and tissue insulin sensitivity were assessed. CAPN-10 UCSNP44,-43,-19 and -63 were genotyped.. (1) In Chinese NGT subjects, the major allele of UCSNP-44 was allele T (frequency=91%), of UCSNP43 was G(89%), of UCSNP-19 was I (3 repeats of a 32 bp sequence) (67%) and of UCSNP-63 was C allele (79%). Significant differences were observed in comparison of these allele frequencies in Chinese to those in other ethnic groups reported in the literature. (2) 14 genotype combinations of these four SNPs were observed in Chinese NGT subjects. 69% of the NGT population was composed of four genotype combinations, in the order of UCSNP44,-43,-19 and -63, i.e., combination A:TT-GG-DI-CC(haplotype combination was 1121/1111) (frequency=10%), combination B:TT-GA-II-CC(1121/1221)(10%), combination C:TT-GG-II-CC(1121/1121)(26%) and combination D:TT-GG-DI-CT(1121/1112)(22%).(3) The frequencies of the above mentioned SNP in single or in combinations were not different significantly between NGT and T2DM groups. (4) The variation of clinical metabolic parameter levels shifted from completely normal towards abnormal glucose intolerance among genotype combination subgroups. In comparison between combination A and combination D, subjects in the former subgroups had: higher PG levels with delayed peak after glucose challenge; less and lower decrement of FFA levels after challenge with no rising in late stage; higher insulin levels with delayed peak after challenge; and the tendency of decreased insulin sensitivity. More than half of the comparisons remained statistically significant after adjusted with age, gender, body mass index and waist circumference.. The variation of calpain-10 gene has impact on the variation of clinical metabolic parameter levels related to type 2 diabetes mellitus. Such impact depends upon the haplotypes as well as the haplotype combination of calpain-10 gene variations.

Topics: Alleles; Blood Glucose; C-Peptide; Calpain; Diabetes Mellitus, Type 2; DNA; Fatty Acids, Nonesterified; Female; Gene Frequency; Genetic Variation; Glucose Tolerance Test; Humans; Insulin; Male; Middle Aged; Polymorphism, Single Nucleotide

Topics: Calpain; Diabetes Mellitus, Type 2; Ethnicity; Genotype; Humans; Mutation; Phenotype

Type 2 or non-insulin-dependent diabetes mellitus (NIDDM) is the most common form of diabetes worldwide, affecting approximately 4% of the world's adult population. It is multifactorial in origin with both genetic and environmental factors contributing to its development. A genome-wide screen for type 2 diabetes genes carried out in Mexican Americans localized a susceptibility gene, designated NIDDM1, to chromosome 2. Here we describe the positional cloning of a gene located in the NIDDM1 region that shows association with type 2 diabetes in Mexican Americans and a Northern European population from the Botnia region of Finland. This putative diabetes-susceptibility gene encodes a ubiquitously expressed member of the calpain-like cysteine protease family, calpain-10 (CAPN10). This finding suggests a novel pathway that may contribute to the development of type 2 diabetes.

Topics: Adult; Amino Acid Sequence; Calpain; Chromosome Mapping; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Finland; Gene Frequency; Genetic Markers; Genetic Predisposition to Disease; Genetic Variation; Genome, Human; Haplotypes; Humans; Mexican Americans; Molecular Sequence Data; Polymorphism, Genetic; Risk Assessment; United States; White People

Topics: Calpain; Cloning, Molecular; Diabetes Mellitus, Type 2

Previous linkage studies in Mexican-Americans localized a major susceptibility locus for type 2 diabetes, NIDDM1, to chromosome 2q. This evidence for linkage to type 2 diabetes was recently found to be associated with a common G-->A polymorphism (UCSNP-43) within the CAPN10 gene. The at-risk genotype was homozygous for the UCSNP-43 G allele. In the present study among Pima Indians, the UCSNP-43 G/G genotype was not associated with an increased prevalence of type 2 diabetes. However, Pima Indians with normal glucose tolerance, who have a G/G genotype at UCSNP-43, were found to have decreased rates of postabsorptive and insulin-stimulated glucose turnover that appear to result from decreased rates of glucose oxidation. In addition, G/G homozygotes were found to have reduced CAPN10 mRNA expression in their skeletal muscle. A decreased rate of insulin-mediated glucose turnover, or insulin resistance, is one mechanism by which the polymorphism in CAPN10 may increase susceptibility to type 2 diabetes mellitus in older persons.

Topics: Adolescent; Adult; Age Factors; Arizona; Biopsy; Blood Glucose; Calpain; Child; Diabetes Mellitus, Type 2; Female; Genotype; Glucose Tolerance Test; Humans; Indians, North American; Insulin Resistance; Male; Middle Aged; Muscle Proteins; Muscles; Polymorphism, Genetic; RNA, Messenger; Sex Factors

Topics: Calpain; Chromosome Mapping; Chromosomes, Human, Pair 2; Diabetes Mellitus, Type 2; Expressed Sequence Tags; Genetic Predisposition to Disease; Humans; Mexican Americans; Polymorphism, Genetic; United States

Translocation of calcium activated neutral proteinase from cytosol to plasma membrane, concurrently with decrease in the activity of membrane bound Ca2+/Mg2+ ATPase has been detected in diabetic polymorphonuclear leucocytes. Plausible involvement of the extralysosomal proteinase in the derangement of the Ca2+/Mg2+ ATPase is indicated by non restoration of the enzyme activity on treatment with activators such as trypsin or calmodulin and enhanced membrane translocation of the proteinase observed with concomitant decrease in the activity of Ca2+/Mg2+ ATPase in normal neutrophils on insult with diabetic serum factor.

Topics: Adult; Ca(2+) Mg(2+)-ATPase; Calpain; Diabetes Mellitus, Type 2; Female; Humans; Male; Middle Aged; Neutrophils

Topics: Calpain; Diabetes Mellitus, Type 2; Endopeptidases; Glucose; Humans; Islets of Langerhans; Receptor, Insulin