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Bruder-Nascimento T, Kennard S, Antonova G, Mintz J, Bence K, de Chantemèle EJ. Ptp1b deletion in pro-opiomelanocortin neurons increases energy expenditure and impairs endothelial function via TNF-α dependent mechanisms. Clin Sci (Lond) 2016; 130:881-893. [DOI: 10.1042/cs20160073] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Protein tyrosine phosphatase 1b (Ptp1b) is a negative regulator of leptin and insulin-signalling pathways. Its targeted deletion in proopiomelanocortin (POMC) neurons protects mice from obesity and diabetes by increasing energy expenditure. Inflammation accompanies increased energy expenditure. Therefore, the present study aimed to determine whether POMC-Ptp1b deletion increases energy expenditure via an inflammatory process, which would impair endothelial function. We characterized the metabolic and cardiovascular phenotypes of Ptp1b+/+ and POMC-Ptp1b−/− mice. Clamp studies revealed that POMC-Ptp1b deletion reduced body fat and increased energy expenditure as evidenced by a decrease in feed efficiency and an increase in oxygen consumption and respiratory exchange ratio. POMC-Ptp1b deletion induced a 2.5-fold increase in plasma tumour necrosis factor α (TNF-α) levels and elevated body temperature. Vascular studies revealed an endothelial dysfunction in POMC-Ptp1b−/− mice. Nitric oxide synthase inhibition [N-nitro-L-arginine methyl ester (L-NAME)] reduced relaxation to a similar extent in Ptp1b+/+ and POMC-Ptp1b−/− mice. POMC-Ptp1b deletion decreased ROS-scavenging enzymes [superoxide dismutases (SODs)] whereas it increased ROS-generating enzymes [NADPH oxidases (NOXs)] and cyclooxygenase-2 (COX-1) expression, in aorta. ROS scavenging or NADPH oxidase inhibition only partially improved relaxation whereas COX-2 inhibition and thromboxane-A2 (TXA2) antagonism fully restored relaxation in POMC-Ptp1b−/− mice. Chronic treatment with the soluble TNF-α receptor etanercept decreased body temperature, restored endothelial function and reestablished aortic COX-2, NOXs and SOD expression to their baseline levels in POMC-Ptp1b−/− mice. However, etanercept promoted body weight gain and decreased energy expenditure in POMC-Ptp1b−/− mice. POMC-Ptp1b deletion increases plasma TNF-α levels, which contribute to body weight regulation via increased energy expenditure and impair endothelial function via COX-2 and ROS-dependent mechanisms.
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Affiliation(s)
- Thiago Bruder-Nascimento
- Physiology Department, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, U.S.A
| | - Simone Kennard
- Physiology Department, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, U.S.A
| | - Galina Antonova
- Physiology Department, Medical College of Georgia at Georgia Regents University, Augusta, GA 30912, U.S.A
| | - James D. Mintz
- Vascular Biology Center, Georgia Regents University, Augusta, GA 30912, U.S.A
| | - Kendra K. Bence
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, U.S.A
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Hollensted M, Ahluwalia TS, Have CT, Grarup N, Fonvig CE, Nielsen TRH, Trier C, Paternoster L, Pedersen O, Holm JC, Sørensen TIA, Hansen T. Common variants in LEPR, IL6, AMD1, and NAMPT do not associate with risk of juvenile and childhood obesity in Danes: a case-control study. BMC MEDICAL GENETICS 2015; 16:105. [PMID: 26558825 PMCID: PMC4642628 DOI: 10.1186/s12881-015-0253-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 11/09/2015] [Indexed: 01/11/2023]
Abstract
Background Childhood obesity is a highly heritable disorder, for which the underlying genetic architecture is largely unknown. Four common variants involved in inflammatory-adipokine triggering (IL6 rs2069845, LEPR rs1137100, NAMPT rs3801266, and AMD1 rs2796749) have recently been associated with obesity and related traits in Indian children. The current study aimed to examine the effect of these variants on risk of childhood/juvenile onset obesity and on obesity-related quantitative traits in two Danish cohorts. Methods Genotype information was obtained for 1461 young Caucasian men from the Genetics of Overweight Young Adults (GOYA) study (overweight/obese: 739 and normal weight: 722) and the Danish Childhood Obesity Biobank (TDCOB; overweight/obese: 1022 and normal weight: 650). Overweight/obesity was defined as having a body mass index (BMI) ≥25 kg/m2; among children and youths, this cut-off was defined using age and sex-specific cut-offs corresponding to an adult body mass index ≥25 kg/m2. Risk of obesity was assessed using a logistic regression model whereas obesity-related quantitative measures were analyzed using a general linear model (based on z-scores) stratifying on the case status and adjusting for age and gender. Meta-analyses were performed using the fixed effects model. Results No statistically significant association with childhood/juvenile obesity was found for any of the four gene variants among the individual or combined analyses (rs2069845 OR: 0.94 CI: 0.85–1.04; rs1137100 OR: 1.01 CI: 0.90–1.14; rs3801266: 0.96 CI: 0.84–1.10; rs2796749 OR: 1.02 CI: 0.90–1.15; p > 0.05). However, among normal weight children and juvenile men, the LEPR rs1137100 A-allele significantly associated with lower BMI (β = −0.12, p = 0.0026). Conclusions The IL6, LEPR, NAMPT, and AMD1 gene variants previously found to associate among Indian children did not associate with risk of obesity or obesity-related quantitative measures among Caucasian children and juvenile men from Denmark.
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Affiliation(s)
- Mette Hollensted
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark.
| | - Tarunveer S Ahluwalia
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark. .,COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Ledreborg Allé 34, DK-2820, Copenhagen, Denmark. .,Steno Diabetes Center, Gentofte, Denmark.
| | - Christian Theil Have
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark.
| | - Niels Grarup
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark.
| | - Cilius Esmann Fonvig
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark. .,The Children's Obesity Clinic, Department of Pediatrics, Copenhagen University Hospital Holbæk, Holbæk, Denmark.
| | - Tenna Ruest Haarmark Nielsen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark. .,The Children's Obesity Clinic, Department of Pediatrics, Copenhagen University Hospital Holbæk, Holbæk, Denmark.
| | - Cæcilie Trier
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark. .,The Children's Obesity Clinic, Department of Pediatrics, Copenhagen University Hospital Holbæk, Holbæk, Denmark.
| | - Lavinia Paternoster
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, UK.
| | - Oluf Pedersen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark.
| | - Jens-Christian Holm
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, UK.
| | - Thorkild I A Sørensen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark. .,MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, UK. .,Institute of Preventive Medicine, Bispebjerg and Frederiksberg Hospital, The Capital Region, Copenhagen, Denmark.
| | - Torben Hansen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, DIKU Building, Universitetsparken 1, 2100, Copenhagen, Denmark.
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Feldhammer M, Uetani N, Miranda-Saavedra D, Tremblay ML. PTP1B: a simple enzyme for a complex world. Crit Rev Biochem Mol Biol 2013; 48:430-45. [PMID: 23879520 DOI: 10.3109/10409238.2013.819830] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Our understanding of the fundamental regulatory roles that tyrosine phosphatases play within cells has advanced significantly in the last two decades. Out-dated ideas that tyrosine phosphatases acts solely as the "off" switch counterbalancing the action of tyrosine kinases has proved to be flawed. PTP1B is the most characterized of all the tyrosine phosphatases and it acts as a critical negative and positive regulator of numerous signaling cascades. PTP1B's direct regulation of the insulin and the leptin receptors makes it an ideal therapeutic target for type II diabetes and obesity. Moreover, the last decade has also seen several reports establishing PTP1B as key player in cancer serving as both tumor suppressor and tumor promoter depending on the cellular context. Despite many key advances in these fields one largely ignored area is what role PTP1B may play in the modulation of immune signaling. The important recognition that PTP1B is a major negative regulator of Janus kinase - signal transducer and activator of transcription (JAK-STAT) signaling throughout evolution places it as a key link between metabolic diseases and inflammation, as well as a unique regulator between immune response and cancer. This review looks at the emergence of PTP1B through evolution, and then explore at the cell and systemic levels how it is controlled physiologically. The second half of the review will focus on the role(s) PTP1B can play in disease and in particular its involvement in metabolic syndromes and cancer. Finally we will briefly examine several novel directions in the development of PTP1B pharmacological inhibitors.
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Variants of insulin-signaling inhibitor genes in type 2 diabetes and related metabolic abnormalities. Int J Genomics 2013; 2013:376454. [PMID: 23762820 PMCID: PMC3674720 DOI: 10.1155/2013/376454] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 04/23/2013] [Indexed: 02/08/2023] Open
Abstract
Insulin resistance has a central role in the pathogenesis of several metabolic diseases, including type 2 diabetes, obesity, glucose intolerance, metabolic syndrome, atherosclerosis, and cardiovascular diseases. Insulin resistance and related traits are likely to be caused by abnormalities in the genes encoding for proteins involved in the composite network of insulin-signaling; in this review we have focused our attention on genetic variants of insulin-signaling inhibitor molecules. These proteins interfere with different steps in insulin-signaling: ENPP1/PC-1 and the phosphatases PTP1B and PTPRF/LAR inhibit the insulin receptor activation; INPPL1/SHIP-2 hydrolyzes PI3-kinase products, hampering the phosphoinositide-mediated downstream signaling; and TRIB3 binds the serine-threonine kinase Akt, reducing its phosphorylation levels. While several variants have been described over the years for all these genes, solid evidence of an association with type 2 diabetes and related diseases seems to exist only for rs1044498 of the ENPP1 gene and for rs2295490 of the TRIB3 gene. However, overall the data recapitulated in this Review article may supply useful elements to interpret the results of novel, more technically advanced genetic studies; indeed it is becoming increasingly evident that genetic information on metabolic diseases should be interpreted taking into account the complex biological pathways underlying their pathogenesis.
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Gu P, Jiang W, Chen M, Lu B, Shao J, Du H, Jiang S. Association of leptin receptor gene polymorphisms and essential hypertension in a Chinese population. J Endocrinol Invest 2012; 35:859-65. [PMID: 22293279 DOI: 10.3275/8238] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND The leptin receptor (LEPR) is an important regulator of leptin activity and resistance. Several single nucleotide polymorphisms (SNP) of LEPR have been linked to diseases accompanying obesity and/or obesity-related diseases in different populations. However, the results from published studies remain inconsistent rather than conclusive. AIM To investigate whether LEPR SNP are associated with essential hypertension and related metabolic traits in Chinese subjects. MATERIALS AND METHODS A total of 544 Chinese patients with hypertension and 357 non-hypertensive subjects were screened. The genotypes of LEPR polymorphisms were determined by PCR-restriction fragment length polymorphism methods. Demographic and biochemical characteristics including waist circumference, waist-to-hip ratio, body mass index (BMI), lipids profiles, glucose metabolism, and leptin levels were obtained for analysis. RESULTS This case-control study showed associations between the frequencies of AA genotype and A allele of Gln223Arg and hypertension (p=0.029, p=0.002, respectively). Furthermore, the Gln223Arg polymorphism was significantly associated with plasma leptin levels (p<0.001), while no correlations between Lys109Arg SNP and hypertension were found. Multivariate logistic regression analysis evidenced that A allele carriers of Gln223Arg (AA+AG) showed higher risks of hypertension than GG carriers after adjustment of age and sex (adjusted odds ratio: 1.549, 95% confidence interval: 1.031- 2.036, p=0.035). BMI, fasting serum insulin, oral glucose tolernace test (OGTT)-2h glucose, serum leptin, as well as LDL-cholesterol (LDL-C) levels were also independent risk factors of hypertension in this population. In addition, significant associations were observed between the Gln223Arg and Lys109Arg SNP and serum total cholesterol, LDL-C, and fasting plasma glucose levels in hypertensive patients. Besides, A allele of Gln223Arg had raised diastolic blood pressure, compared with GG carriers (p=0.001). While variance of Lys109Arg was associated with waist-to-hip ratio, OGTT-2h glucose, and homeostasis model assessment of insulin resistance (p<0.05). CONCLUSIONS LEPR polymorphisms may be a marker for susceptibility to essential hypertension in Chinese subjects, and be involved in the development of several features including dyslipidemia and impaired glucose regulation in hypertension subjects.
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Affiliation(s)
- P Gu
- Department of Endocrinology, Nanjing General Hospital of Nanjing Command, Jiangsu Province, PR China
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Pérusse L, Rankinen T, Zuberi A, Chagnon YC, Weisnagel SJ, Argyropoulos G, Walts B, Snyder EE, Bouchard C. The Human Obesity Gene Map: The 2004 Update. ACTA ACUST UNITED AC 2012; 13:381-490. [PMID: 15833932 DOI: 10.1038/oby.2005.50] [Citation(s) in RCA: 212] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This paper presents the eleventh update of the human obesity gene map, which incorporates published results up to the end of October 2004. Evidence from single-gene mutation obesity cases, Mendelian disorders exhibiting obesity as a clinical feature, transgenic and knockout murine models relevant to obesity, quantitative trait loci (QTLs) from animal cross-breeding experiments, association studies with candidate genes, and linkages from genome scans is reviewed. As of October 2004, 173 human obesity cases due to single-gene mutations in 10 different genes have been reported, and 49 loci related to Mendelian syndromes relevant to human obesity have been mapped to a genomic region, and causal genes or strong candidates have been identified for most of these syndromes. There are 166 genes which, when mutated or expressed as transgenes in the mouse, result in phenotypes that affect body weight and adiposity. The number of QTLs reported from animal models currently reaches 221. The number of human obesity QTLs derived from genome scans continues to grow, and we have now 204 QTLs for obesity-related phenotypes from 50 genome-wide scans. A total of 38 genomic regions harbor QTLs replicated among two to four studies. The number of studies reporting associations between DNA sequence variation in specific genes and obesity phenotypes has also increased considerably with 358 findings of positive associations with 113 candidate genes. Among them, 18 genes are supported by at least five positive studies. The obesity gene map shows putative loci on all chromosomes except Y. Overall, >600 genes, markers, and chromosomal regions have been associated or linked with human obesity phenotypes. The electronic version of the map with links to useful publications and genomic and other relevant sites can be found at http://obesitygene.pbrc.edu.
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Affiliation(s)
- Louis Pérusse
- Division of Kinesiology, Department of Social and Preventive Medicine, Faculty of Medicine, Laval University, Sainte-Foy, Québec, Canada
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Ukkola O, Rankinen T, Lakka T, Leon AS, Skinner JS, Wilmore JH, Rao DC, Kesäniemi YA, Bouchard C. Protein Tyrosine Phosphatase 1B Variant Associated with Fat Distribution and Insulin Metabolism. ACTA ACUST UNITED AC 2012; 13:829-34. [PMID: 15919835 DOI: 10.1038/oby.2005.95] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Protein tyrosine phosphatase 1B (PTPN1) affects the regulation of insulin signaling and energy metabolism. We studied whether polymorphisms in the PTPN1 gene impact body fat distribution in the HERITAGE Family Study cohort in 502 white and 276 black subjects. Insulin sensitivity index, glucose disappearance index, acute insulin response to glucose (AIR(glucose)), and the disposition index (DI) were obtained from the frequently sampled intravenous glucose tolerance test. White subjects with the G82G at the PTPN1 IVS6+G82A polymorphism had higher body fat levels (p = 0.031) and sum of eight skinfolds (p = 0.003) and highest subcutaneous fat on the limbs (p = 0.002). G82A subjects had the lowest AIR(glucose) (p = 0.005) and disposition index (p = 0.040). Interaction effects between PTPN1 and leptin receptor gene variants influenced insulin sensitivity index and AIR(glucose) (p from 0.006 to 0.010). The variant PTPN1 Pro387Leu was associated with lower fasting insulin level (p = 0.035) and glucose disappearance index (p = 0.038). In summary, PTPN1 IVS6+G82G homozygotes showed higher levels of all measures of adiposity. G82 allele heterozygotes are potentially at higher risk for type 2 diabetes. Gene-gene interactions between the PTPN1 and leptin receptor genes contributed to the phenotypic variability of insulin sensitivity. The PTPN1 Pro387Leu variant was associated with lower glucose tolerance.
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Affiliation(s)
- Olavi Ukkola
- Pennington Biomedical Research Center, Louisiana State University, 6400 Perkins Road, Baton Rouge, LA 70808-4124, USA
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Zhou X, Xu W, Chen J. The 981C>T polymorphism in protein tyrosine phosphatase 1B is associated with decreased risk of coronary artery disease in Chinese Han population. Atherosclerosis 2011; 218:147-50. [PMID: 21676396 DOI: 10.1016/j.atherosclerosis.2011.05.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 05/17/2011] [Accepted: 05/17/2011] [Indexed: 01/12/2023]
Abstract
OBJECTIVE The present study was designed to investigate the potential association between the 981C>T polymorphism in protein tyrosine phosphatase 1B (PTP-1B) and coronary artery disease (CAD). METHODS We conducted a hospital-based case-control study with 864 CAD patients and 1008 controls to explore the association between the PTP-1B 981C>T polymorphism and risk of CAD in Chinese Han population. RESULTS Subjects with the variant genotypes (CT+TT) had a 52% decreased risk of CAD relative to CC carriers (adjusted odds ratio, 0.48; 95% confidence interval, 0.39-0.60). The 981C>T polymorphism was associated with a higher body mass index and serum triglyceride levels in both CAD patients and controls. Moreover, this polymorphism was found to be associated with a lower serum glucose levels in cases, but not in controls. CONCLUSION Our study demonstrates that the PTP-1B 981C>T polymorphism is associated with decreased risk of CAD in Chinese Han population.
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Affiliation(s)
- Xiang Zhou
- Department of Cardiology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, People's Republic of China
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Furusawa T, Naka I, Yamauchi T, Natsuhara K, Kimura R, Nakazawa M, Ishida T, Nishida N, Eddie R, Ohtsuka R, Ohashi J. The serum leptin level and body mass index in Melanesian and Micronesian Solomon Islanders: focus on genetic factors and urbanization. Am J Hum Biol 2010; 23:435-44. [PMID: 21648011 DOI: 10.1002/ajhb.21124] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 09/03/2010] [Accepted: 09/30/2010] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES This study examined the association between the serum leptin level and body mass index (BMI) and the effects of urbanization and polymorphisms of leptin (LEP) or leptin receptor (LEPR) genes on the leptin level in three Solomon Islands populations. METHODS A Melanesian population living in a remote area (participants: 106 males and 106 females, ages: 18-74 years), a Melanesian population in an urban area (89 and 94, 18-79 years), and a Micronesian population who migrated to a peri-urban area in the 1960s (84 and 69, 18-71 years) were studied. Anthropometric and serum leptin measurements and genotyping for LEP G-2548A and LEPR K109R and Q223R were performed. RESULTS The prevalence of obesity (BMI ≥ 30 kg/m(2)) was the highest in the Micronesian population (30.1%), followed by the urban (18.6%) and the rural (2.4%) Melanesian population. The serum leptin concentration was the highest in the urban Melanesian, followed by the Micronesian and the rural Melanesian populations (P < 0.05). Interestingly, the parameter coefficients of the leptin concentrations on the BMIs were nearly identical in the urban and rural Melanesians after adjusting for age and gender. The LEPR 223Q/Q genotype was associated with an increased leptin level only in the Micronesian population after adjusting for BMI (P = 0.0008 and 0.0016 referenced to the Q/R and the R/R types, respectively). CONCLUSIONS These observations suggest that the increase in obesity in the Micronesians had a genetic component while that in Melanesians might have been related with the urbanization.
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Affiliation(s)
- Takuro Furusawa
- Network for Education and Research on Asia, The University of Tokyo, Institute for Advanced Studies on Asia, The University of Tokyo, Japan.
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Gu P, Jiang W, Du H, Shao J, Lu B, Wang J, Zou D. Protein tyrosine phosphatase 1B gene polymorphisms and essential hypertension: a case-control study in Chinese population. J Endocrinol Invest 2010; 33:483-8. [PMID: 20101100 DOI: 10.1007/bf03346629] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Protein tyrosine phosphatase (PTP)- 1B, encoded by the PTPN1 gene, negatively regulates insulin signaling by dephosphorylating the phosphotyrosine residues of the insulin receptor kinase activation segment. Several rare single nucleotide polymorphisms (SNP) have been linked to diseases accompanying insulin resistance such as Type 2 diabetes, obesity, and dyslipidemia in different populations. AIM To investigate whether PTP-1B SNP are associated with hypertension and hypertension-related metabolic traits in Chinese subjects. MATERIALS AND METHODS A total of 239 Chinese patients with hypertension and 141 non-hypertensive subjects were screened. The genotypes of PTP-1B gene polymorphisms were determined by PCR-restriction fragment length polymorphism methods. RESULTS The case-control study showed associations between the frequencies of T allelic g54281 T>A and A allele of I5/37C>A and hypertension (p<0.0001, p=0.0371, respectively). In addition, significant associations were observed between the IVS6+G82A polymorphism and waist circumference, total cholesterol, and LDL-cholesterol levels in hypertensive patients (p=0.0005 approximately 0.0260). And g54281 T allele was associated with higher plasma triglyceride (p=0.0390) and LDL-cholesterol concentration (p=0.0141), while g58585 T>C was associated with body mass index (BMI) (p=0.0308), waist circumference (p=0.0216), and homeostasis model assessment of insulin resistance (p=0.047). Multivariate logistic regression analysis showed that T allele carriers of g54281T>A and A allele carriers of I5/37C>A had higher risks of hypertension independent of age, gender, BMI, glucose levels, and lipids profiles [odds ratio (OR): 1.79, 95% confidence interval (CI): 1.09- 2.96, p=0.02; OR: 1.66, 95% CI: 1.13-2.44, p=0.01, respectively]. CONCLUSIONS PTP-1B polymorphisms contribute to pathogenesis of hypertension in Chinese subjects and PTP-1B SNP may be involved in the development of several features including dyslipidemia and obesity in hypertensive subjects.
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Affiliation(s)
- P Gu
- Department of Endocrinology, Nanjing General Hospital of Nanjing Military Command, Nanjing 210002, China
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MohammadTaghvaei N, Meshkani R, Taghikhani M, Larijani B, Adeli K. Palmitate Enhances Protein Tyrosine Phosphatase 1B (PTP1B) Gene Expression at Transcriptional Level in C2C12 Skeletal Muscle Cells. Inflammation 2010; 34:43-8. [DOI: 10.1007/s10753-010-9206-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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12
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Furusawa T, Naka I, Yamauchi T, Natsuhara K, Kimura R, Nakazawa M, Ishida T, Inaoka T, Matsumura Y, Ataka Y, Nishida N, Tsuchiya N, Ohtsuka R, Ohashi J. The Q223R polymorphism in LEPR is associated with obesity in Pacific Islanders. Hum Genet 2009; 127:287-94. [DOI: 10.1007/s00439-009-0768-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Hong KW, Jin HS, Lim JE, Ryu HJ, Ahn YJ, Lee JY, Han BG, Shin HD, Cho NH, Shin C, Woo JT, Park HK, Oh BS. Protein Tyrosine Phosphatase N1 Gene Variants Associated with Type 2 Diabetes Mellitus and Its Related Phenotypes in the Korean Population. Genomics Inform 2008. [DOI: 10.5808/gi.2008.6.3.099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Wang ZQ, Ribnicky D, Zhang XH, Raskin I, Yu Y, Cefalu WT. Bioactives of Artemisia dracunculus L enhance cellular insulin signaling in primary human skeletal muscle culture. Metabolism 2008; 57:S58-64. [PMID: 18555856 PMCID: PMC2981033 DOI: 10.1016/j.metabol.2008.04.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
An alcoholic extract of Artemisia dracunculus L (PMI 5011) has been shown to decrease glucose and improve insulin levels in animal models, suggesting an ability to enhance insulin sensitivity. We sought to assess the cellular mechanism by which this botanical affects carbohydrate metabolism in primary human skeletal muscle culture. We measured basal and insulin-stimulated glucose uptake, glycogen accumulation, phosphoinositide 3 (PI-3) kinase activity, and Akt phosphorylation in primary skeletal muscle culture from subjects with type 2 diabetes mellitus incubated with or without various concentrations of PMI 5011. We also analyzed the abundance of insulin receptor signaling proteins, for example, IRS-1, IRS-2, and PI-3 kinase. Glucose uptake was significantly increased in the presence of increasing concentrations of PMI 5011. In addition, glycogen accumulation, observed to be decreased with increasing free fatty acid levels, was partially restored with PMI 5011. PMI 5011 treatment did not appear to significantly affect protein abundance for IRS-1, IRS-2, PI-3 kinase, Akt, insulin receptor, or Glut-4. However, PMI 5011 significantly decreased levels of a specific protein tyrosine phosphatase, that is, PTP1B. Time course studies confirmed that protein abundance of PTP1B decreases in the presence of PMI 5011. The cellular mechanism of action to explain the effects by which an alcoholic extract of A dracunculus L improves carbohydrate metabolism on a clinical level may be secondary to enhancing insulin receptor signaling and modulating levels of a specific protein tyrosine phosphatase, that is, PTP1B.
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Affiliation(s)
- Zhong Q. Wang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
| | - David Ribnicky
- Biotech Center, Rutgers University, New Brunswick, NJ 08901, USA
| | - Xian H. Zhang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
| | - Ilya Raskin
- Biotech Center, Rutgers University, New Brunswick, NJ 08901, USA
| | - Yongmei Yu
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
| | - William T. Cefalu
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
- Corresponding author. Tel.: +1 225 763 2654; fax: +1 225 763 3030. (W.T. Cefalu)
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Common SNPs in LEP and LEPR associated with birth weight and type 2 diabetes-related metabolic risk factors in twins. Int J Obes (Lond) 2008; 32:1233-9. [PMID: 18490929 DOI: 10.1038/ijo.2008.68] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Children born small for gestational age are at increased risk of developing type 2 diabetes in adulthood. The satiety signal leptin that regulates food intake and energy expenditure might be a possible molecular link, as umbilical cord leptin levels are positively correlated with birth weight. In the present study, we examined whether common single nucleotide polymorphisms (SNPs) in the leptin (LEP; 19G>A) gene and its receptor (LEPR; Q223R and K109R) are associated with birth weight and adult metabolic risk factors for type 2 diabetes in twins. DESIGN SNPs were genotyped in 396 monozygotic and 232 dizygotic twins (286 men and 342 women, mean age 25 years) recruited from the East Flanders Prospective Twin Survey. Data were analysed using linear mixed models. RESULTS The LEPR K109R SNP was associated with birth weight (KK, KR and RR (95% confidence interval, CI): 2511 (2465-2557), 2575 (2516-2635) and 2726 (2606-2845) gram; P(additive)=0.001). Also the LEPR Q223R SNP showed a significant association with weight at birth (QQ, QR and RR (95% CI): 2492 (2431-2554), 2545 (2495-2595) and 2655 (2571-2740) gram; P(additive)=0.003). Furthermore, an interaction between the LEPR K109R and the Q223R SNP on birth weight was observed (P=0.014). G allele carriers of the LEP 19G>A SNP had higher high-density lipoprotein (HDL) cholesterol levels compared to 19A homozygotes (GX vs AA (95% CI): 1.62 (1.58-1.66) vs 1.49 (1.40-1.58) mmol l(-1); P(recessive)=0.013). CONCLUSIONS This study indicates that leptin may act as a growth-promoting signal during fetal development, and suggests a possible role for the LEPR in explaining the inverse relationship between birth weight and the development of metabolic diseases in adulthood. Additionally, these results suggest that the LEP 19G>A SNP affect HDL cholesterol levels.
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de Luis DA, Gonzalez Sagrado M, Aller R, Izaola O, Conde R. Influence of Lys656Asn polymorphism of the leptin receptor gene on insulin resistance in nondiabetic obese patients. J Diabetes Complications 2008; 22:199-204. [PMID: 18413223 DOI: 10.1016/j.jdiacomp.2006.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Revised: 10/10/2006] [Accepted: 10/12/2006] [Indexed: 11/21/2022]
Abstract
BACKGROUND Alterations of the normal leptin receptor (LEPR) gene may be involved in the development of obesity. Leptin has been shown to be able to modulate insulin secretion. Different polymorphisms in the LEPR gene have been studied, albeit with unclear results. The polymorphism on codon 656 produces a change in charge, making this change possibly functional. OBJECTIVE The objective of this study was to investigate the influence of Lys656Asn polymorphism in the LEPR gene on serum insulin, glucose values, and insulin resistance in the fasted state among obese men and women without diabetes mellitus. DESIGN Two hundred thirty-three (body mass index, >30 kg/m(2)) nondiabetic obese patients were analyzed. Indirect calorimetry, tetrapolar electrical bioimpedance, blood pressure determination, serial assessment of nutritional intake with 3-day written food records, and biochemical analysis were performed. Statistical analysis was performed for Lys656/Asn656 and Asn656/Asn656 jointly as a mutant allelic group and for Lys656/Lys656 as a wild allelic group. RESULTS The subjects' (67 males and 166 females) mean age and mean body mass index were 43.6+/-16.6 years and 35.3+/-5.6 kg/m(2), respectively. One hundred forty-three patients (61.9%) had the genotype Lys656/Lys656 (wild group), whereas 88 (38.1%) had either the genotype Lys656/Asn656 (n=81; 30.7%) or the genotype Asn656/Asn656 (n=7; 7.4%) (mutant group). Age and sex distribution were similar in both groups. No difference was detected between the mutant and wild allelic groups in anthropometric parameters and dietary intakes. Homeostasis model assessment (HOMA; 2.8+/-1.7 vs. 5.6+/-4.8; P<.05) and insulin (18.1+/-10.7 vs. 32.1+/-25 mUI/ml; P<.05) levels were higher in males with the genotypes Lys656/Asn656 and Asn656/Asn656 than in males with the genotype Lys656/Lys656. Leptin levels were higher in males with a mutant genotype than in males with a wild genotype (39.3+/-23 vs. 63.5+/-28 ng/ml; P<.05). CONCLUSION The novel findings of our study are those of the association of the Lys656/Asn656 and Asn656/Asn656 genotypes with higher levels of insulin, HOMA, and leptin in males and the lack of such an association in females.
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Affiliation(s)
- Daniel A de Luis
- Medicine School and Unit of Investigation, Institute of Endocrinology and Nutrition, Hospital Rio Hortega, University of Valladolid, Valladolid, Spain
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17
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Zabolotny JM, Kim YB, Welsh LA, Kershaw EE, Neel BG, Kahn BB. Protein-tyrosine phosphatase 1B expression is induced by inflammation in vivo. J Biol Chem 2008; 283:14230-41. [PMID: 18281274 DOI: 10.1074/jbc.m800061200] [Citation(s) in RCA: 300] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Protein-tyrosine phosphatase 1B (PTP1B) is a major negative regulator of insulin and leptin sensitivity. PTP1B overexpression in adipose tissue and skeletal muscle of humans and rodents may contribute to insulin resistance and obesity. The mechanisms mediating PTP1B overexpression in obese and diabetic states have been unclear. We find that adipose tissue inflammation and the pro-inflammatory cytokine tumor necrosis factor alpha (TNFalpha) regulate PTP1B expression in vivo. High fat feeding of mice increased PTP1B expression 1.5- to 7-fold in adipose tissue, liver, skeletal muscle, and arcuate nucleus of hypothalamus. PTP1B overexpression in high fat-fed mice coincided with increased adipose tissue expression of the macrophage marker CD68 and TNFalpha, which is implicated in causing obesity-induced insulin resistance. TNFalpha increased PTP1B mRNA and protein levels by 2- to 5-fold in a dose- and time-dependent manner in adipocyte and hepatocyte cell lines. TNFalpha administration in mice increased PTP1B mRNA 1.4- to 4-fold in adipose tissue, liver, skeletal muscle, and hypothalamic arcuate nucleus and PTP1B protein 2-fold in liver. Actinomycin D treatment blocked, and high dose salicylate treatment inhibited by 80%, TNFalpha-induced PTP1B expression in adipocyte cell lines, suggesting TNFalpha may induce PTP1B transcription via nuclear factor kappaB (NFkappaB) activation. Chromatin immunoprecipitation from adipocyte cell lines and liver of mice demonstrated TNFalpha-induced recruitment of NFkappaB subunit p65 to the PTP1B promoter in vitro and in vivo. In mice with diet-induced obesity, TNFalpha deficiency also partly blocked PTP1B overexpression in adipose tissue. Our data suggest that PTP1B overexpression in multiple tissues in obesity is regulated by inflammation and that PTP1B may be a target of anti-inflammatory therapies.
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Affiliation(s)
- Janice M Zabolotny
- Division of Endocrinology, Diabetes, and Metabolism and Cancer Biology Program, Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA.
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18
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Meshkani R, Taghikhani M, Al-Kateb H, Larijani B, Khatami S, Sidiropoulos GK, Hegele RA, Adeli K. Polymorphisms within the Protein Tyrosine Phosphatase 1B (PTPN1) Gene Promoter: Functional Characterization and Association with Type 2 Diabetes and Related Metabolic Traits. Clin Chem 2007; 53:1585-92. [PMID: 17634210 DOI: 10.1373/clinchem.2007.088146] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Abstract
Background: Protein tyrosine phosphatase 1B (PTPN1) dephosphorylates insulin receptors and attenuates insulin signaling. Polymorphisms in the coding sequence of PTPN1 have been variably associated with type 2 diabetes (T2D). We hypothesized that variations within the PTPN1 promoter might contribute to the development of T2D and related metabolic traits.
Methods: We screened 2.0 kb of PTPN1 promoter in 174 T2D patients and 412 controls using PCR and denaturing HPLC. Association analysis was performed between diabetes and related traits and single-nucleotide polymorphism genotypes. We functionally tested 2 variants (−1023C>A and −51delA) by measuring their influence on luciferase activity in HepG2 cells and performing the electrophoretic mobility shift assay (EMSA).
Results: One common (−1023C>A) and 6 rare (−51delA, −451A>G, −467T>C, −1045G>A, −1286-3bp-del, and −1291-9bp-del) variants were identified in the PTPN1 promoter. The −1023(C) allele had significant association with T2D that disappeared after we adjusted for established diabetes risk factors. The alleles of −1023C>A and −51delA variants did not show significant effects on the biochemical markers after adjustment for established diabetes risk factors in the nondiabetic and diabetic groups separately. The −51delA variant decreased luciferase gene expression in HepG2 cells by 2-fold. EMSA revealed a weaker binding of −51delA to specific protein family proteins compared with the A allele. The −1023C>A variant had no influence in either experiment.
Conclusions: The PTPN1 promoter variants −1023C>A and −51delA (which appears to be functional) were not associated with T2D or related traits in this study but must be investigated in a larger population to reveal any potential metabolic association.
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Affiliation(s)
- Reza Meshkani
- Department of Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, I.R. Iran
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19
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Application of nutrigenomic concepts to Type 2 diabetes mellitus. Nutr Metab Cardiovasc Dis 2007; 17:89-103. [PMID: 17276047 DOI: 10.1016/j.numecd.2006.11.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Revised: 11/27/2006] [Accepted: 11/28/2006] [Indexed: 12/13/2022]
Abstract
The genetic makeup that individuals inherit from their ancestors is responsible for variation in responses to food and susceptibility to chronic diseases such as Type 2 diabetes mellitus (T2DM). Common variations in gene sequences, such as single nucleotide polymorphisms, produce differences in complex traits such as height or weight potential, food metabolism, food-gene interactions, and disease susceptibilities. Nutritional genomics, or nutrigenomics, is the study of how foods affect the expression of genetic information in an individual and how an individual's genetic makeup affects the metabolism and response to nutrients and other bioactive components in food. Since both diet and genes alter one's health and susceptibility to disease, identifying genes that are regulated by diet and that cause or contribute to chronic diseases could result in the development of diagnostic tools, individualized intervention, and eventually strategies for maintaining health. Translating this research through clinical studies promises contributions to the development of personalized medicine that includes nutritional as well as drug interventions. Reviewed here are the key nutrigenomic concepts that help explain aspects of the development and complexity of T2DM.
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20
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Abstract
The etiology of type 2 diabetes (T2D) is complex and remains poorly understood. Differences in individual susceptibility to this condition reflect the action of multiple variants, each of which confers a modest effect, and their interactions with a variety of environmental exposures. Several complementary approaches to the identification of the etiological variants have been adopted, though, for all, association analyses provide the final common pathway. The genes and/or chromosomal regions studied have been selected on the basis of their presumed biological relevance to diabetes, known involvement in monogenic forms, or animal models of the condition and/or signals arising from whole-genome linkage scans. These association studies have featured a wide variety of designs and analytical approaches, but reliable biological insights have been few, largely because of difficulties in obtaining reproducible findings. However, in recent years, several examples of robustly replicated associations have emerged, largely as a result of an emphasis on the need for improved power and more appropriate analysis and interpretation. New strategies for the large-scale identification of T2D susceptibility variants are now becoming possible, including the prospect of genuine genome-wide association scans, but caution in their design, analysis, and interpretation remains essential.
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Affiliation(s)
- Eleftheria Zeggini
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, UK
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21
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Rankinen T, Zuberi A, Chagnon YC, Weisnagel SJ, Argyropoulos G, Walts B, Pérusse L, Bouchard C. The human obesity gene map: the 2005 update. Obesity (Silver Spring) 2006; 14:529-644. [PMID: 16741264 DOI: 10.1038/oby.2006.71] [Citation(s) in RCA: 685] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This paper presents the 12th update of the human obesity gene map, which incorporates published results up to the end of October 2005. Evidence from single-gene mutation obesity cases, Mendelian disorders exhibiting obesity as a clinical feature, transgenic and knockout murine models relevant to obesity, quantitative trait loci (QTL) from animal cross-breeding experiments, association studies with candidate genes, and linkages from genome scans is reviewed. As of October 2005, 176 human obesity cases due to single-gene mutations in 11 different genes have been reported, 50 loci related to Mendelian syndromes relevant to human obesity have been mapped to a genomic region, and causal genes or strong candidates have been identified for most of these syndromes. There are 244 genes that, when mutated or expressed as transgenes in the mouse, result in phenotypes that affect body weight and adiposity. The number of QTLs reported from animal models currently reaches 408. The number of human obesity QTLs derived from genome scans continues to grow, and we now have 253 QTLs for obesity-related phenotypes from 61 genome-wide scans. A total of 52 genomic regions harbor QTLs supported by two or more studies. The number of studies reporting associations between DNA sequence variation in specific genes and obesity phenotypes has also increased considerably, with 426 findings of positive associations with 127 candidate genes. A promising observation is that 22 genes are each supported by at least five positive studies. The obesity gene map shows putative loci on all chromosomes except Y. The electronic version of the map with links to useful publications and relevant sites can be found at http://obesitygene.pbrc.edu.
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Affiliation(s)
- Tuomo Rankinen
- Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808-4124, USA
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22
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Park KS, Shin HD, Park BL, Cheong HS, Cho YM, Lee HK, Lee JY, Lee JK, Oh B, Kimm K. Polymorphisms in the leptin receptor (LEPR)--putative association with obesity and T2DM. J Hum Genet 2005; 51:85-91. [PMID: 16333525 DOI: 10.1007/s10038-005-0327-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2005] [Accepted: 10/06/2005] [Indexed: 11/28/2022]
Abstract
Leptin plays an important role in regulating adipose-tissue mass. Leptin controls energy balance and food intake through the leptin receptor in the hypothalamus of the brain, which suggests that some polymorphisms of the leptin receptor gene (LEPR) might contribute to obesity or obesity-related diseases. In an effort to identify genetic polymorphisms in a potential candidate gene for obesity and type 2 diabetes mellitus (T2DM) in the Korean population, we have sequenced the LEPR gene. Thirty-five sequence variants were identified (including 9 novel polymorphisms): 1 single nucleotide polymorphism (SNP) in the promoter region, 1 SNP in the 5' UTR, 8 SNPs in exons (3 non-synonymous SNPs), 23 SNPs in introns, 1 ins/del in the 3' UTR, and 1 SNP in the 3' downstream region. To investigate possible association of LEPR polymorphisms with body mass index (BMI) and the risk of T2DM, we genotyped for 11 polymorphisms in the Korean population (n = 1,463). Using statistical analyses, no significant associations between the genetic polymorphisms in the LEPR gene and the risk of T2DM were detected. However, one non-synonymous SNP in exon 3, +5193G > A (Arg109Lys), showed marginal association with BMI (P = 0.02) and gene dose-dependent genetic effects were observed. The present study provides information about additional genetic polymorphisms in LEPR and positive associations of those polymorphisms with BMI in the Korean population.
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Affiliation(s)
- Kyong Soo Park
- Genome Research Center for Diabetes and Endocrine Disease, Clinical Research Institute, Seoul National University Hospital, Department of Internal Medicine, Seoul National University College of Medicine, 110-744, Seoul, Korea
| | - Hyoung Doo Shin
- Department of Genetic Epidemiology, SNP Genetics, Rm 1407, 14th floor, B-dong, WooLim Lion's Valley, 371-28, Gasan-dong, Geumcheon-Gu, 153-803, Seoul, Korea
| | - Byung Lae Park
- Department of Genetic Epidemiology, SNP Genetics, Rm 1407, 14th floor, B-dong, WooLim Lion's Valley, 371-28, Gasan-dong, Geumcheon-Gu, 153-803, Seoul, Korea
| | - Hyun Sub Cheong
- Department of Genetic Epidemiology, SNP Genetics, Rm 1407, 14th floor, B-dong, WooLim Lion's Valley, 371-28, Gasan-dong, Geumcheon-Gu, 153-803, Seoul, Korea
| | - Young Min Cho
- Genome Research Center for Diabetes and Endocrine Disease, Clinical Research Institute, Seoul National University Hospital, Department of Internal Medicine, Seoul National University College of Medicine, 110-744, Seoul, Korea
| | - Hong Kyu Lee
- Genome Research Center for Diabetes and Endocrine Disease, Clinical Research Institute, Seoul National University Hospital, Department of Internal Medicine, Seoul National University College of Medicine, 110-744, Seoul, Korea
| | - Jong-Young Lee
- National Genome Research Institute, National Institute of Health, 5 Nokbun-dong, Eunpyung-ku, 122-701, Seoul, Korea
| | - Jong-Keuk Lee
- National Genome Research Institute, National Institute of Health, 5 Nokbun-dong, Eunpyung-ku, 122-701, Seoul, Korea
| | - Bermseok Oh
- National Genome Research Institute, National Institute of Health, 5 Nokbun-dong, Eunpyung-ku, 122-701, Seoul, Korea
| | - Kuchan Kimm
- National Genome Research Institute, National Institute of Health, 5 Nokbun-dong, Eunpyung-ku, 122-701, Seoul, Korea.
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23
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Florez JC, Agapakis CM, Burtt NP, Sun M, Almgren P, Råstam L, Tuomi T, Gaudet D, Hudson TJ, Daly MJ, Ardlie KG, Hirschhorn JN, Groop L, Altshuler D. Association testing of the protein tyrosine phosphatase 1B gene (PTPN1) with type 2 diabetes in 7,883 people. Diabetes 2005; 54:1884-91. [PMID: 15919813 DOI: 10.2337/diabetes.54.6.1884] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Protein tyrosine phosphatase (PTP)-1B, encoded by the PTPN1 gene, inactivates the insulin signal transduction cascade by dephosphorylating phosphotyrosine residues in insulin signaling molecules. Due to its chromosomal location under a chromosome 20 linkage peak and the metabolic effects of its absence in knockout mice, it is a candidate gene for type 2 diabetes. Recent studies have associated common sequence variants in PTPN1 with type 2 diabetes and diabetes-related phenotypes. We sought to replicate the association of common single nucleotide polymorphisms (SNPs) and haplotypes in PTPN1 with type 2 diabetes, fasting plasma glucose, and insulin sensitivity in a large collection of subjects. We assessed linkage disequilibrium, selected tag SNPs, and typed these markers in 3,347 cases of type 2 diabetes and 3,347 control subjects as well as 1,189 siblings discordant for type 2 diabetes. Despite power estimated at >95% to replicate the previously reported associations, no statistically significant evidence of association was observed between PTPN1 SNPs or common haplotypes with type 2 diabetes or with diabetic phenotypes.
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Affiliation(s)
- Jose C Florez
- Department of Endocrinology, University Hospital MAS, Lund University, Malmö, Sweden
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Hansen SK, Nielsen EMD, Ek J, Andersen G, Glümer C, Carstensen B, Mouritzen P, Drivsholm T, Borch-Johnsen K, Jørgensen T, Hansen T, Pedersen O. Analysis of separate and combined effects of common variation in KCNJ11 and PPARG on risk of type 2 diabetes. J Clin Endocrinol Metab 2005; 90:3629-37. [PMID: 15797964 DOI: 10.1210/jc.2004-1942] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The separate and combined effects of the PPARG Pro(12)Ala polymorphism and the KCNJ11 Glu(23)Lys polymorphisms on risk of type 2 diabetes were investigated in relatively large-scale, case-control studies. Separate effects of the variants were examined among 1187/1461 type 2 diabetic patients and 4791/4986 middle-aged, glucose-tolerant subjects. The combined analysis involved 1164 type 2 diabetic patients and 4733 middle-aged, glucose-tolerant subjects. In the separate analyses, the K allele of the KCNJ11 Glu(23)Lys associated with type 2 diabetes (odds ratio, 1.19; P = 0.0002), whereas the PPARG Pro(12)Ala showed no significant association with type 2 diabetes. The combined analysis indicated that the two polymorphisms acted in an additive manner to increase the risk of type 2 diabetes, and we found no evidence for a synergistic interaction between them. Analysis of a model with equal additive effects of the two variants showed that the odds ratio for type 2 diabetes increased with 1.14/risk allele (P = 0.003). Together, the two polymorphisms conferred a population-attributable risk for type 2 diabetes of 28%. In conclusion, our results showed no evidence of a synergistic interaction between the KCNJ11 Glu(23)Lys and PPARG Pro(12)Ala polymorphisms, but indicated that they may act in an additive manner to increase the risk of type 2 diabetes.
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Affiliation(s)
- Sara K Hansen
- Steno Diabetes Center and Hagedorn Research Institute, Niels Steensens Vej 2, DK-2820 Gentofte, Denmark
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Gouni-Berthold I, Giannakidou E, Müller-Wieland D, Faust M, Kotzka J, Berthold HK, Krone W. The Pro387Leu variant of protein tyrosine phosphatase-1B is not associated with diabetes mellitus type 2 in a German population. J Intern Med 2005; 257:272-80. [PMID: 15715684 DOI: 10.1111/j.1365-2796.2004.01446.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Diabetes mellitus type 2 (DM-2) is a complex disorder with a strong genetic background. Protein tyrosine phosphatase-1B (PTP-1B) dephosphorylates various receptor protein kinases in vitro, including the beta subunit of the insulin receptor, therefore representing a potential candidate to be involved in the polygenic pathogenesis of DM-2. Recently a Pro387Leu variant of the PTP-1B gene has been associated with an increased risk of DM-2 in a Danish population. Reports from China and Finland failed to confirm this association. DESIGN, SETTING AND SUBJECTS The purpose of the present study was to examine the possible association between the presence of DM-2 and the Pro387Leu polymorphism in a German Caucasian population. A total of 836 subjects (age 20-92 years) participated in the study. The presence of the Pro387Leu variant of the PTP-1B gene was investigated using polymerase chain reaction (PCR) restriction fragment-length polymorphism in 402 subjects with DM-2 (231 men, 171 women, age 63.1 +/- 10.8 years, BMI 28.7 +/- 5.1 kg m(-2)) and in 434 normoglycemic age- and sex-matched control subjects (248 men, 186 women, age 64.4 +/- 6.5 years, BMI 26.5 +/- 3.7 kg m(-2)). RESULTS Nine subjects in the control group and nine in the diabetic group (allelic frequency 0.99% in both groups) carried the Pro387Leu polymorphism. A meta-analysis on published data of >3000 subjects including our own data did not find an association between the polymorphism and DM-2. In addition, the polymorphism had no significant influence on the presence of atherosclerotic disease, whilst the influence of other known cardiovascular risk factors was confirmed. Furthermore, the impact of the mutation on metabolic and anthropometric parameters in both groups was examined. Amongst the controls there were no significant differences in BMI, HDL and LDL cholesterol or blood pressure between the two groups with or without the Pro387Leu polymorphism. The same was true for the diabetic group. Interestingly, in both diabetics and controls, Pro387Leu carriers had significantly higher triglycerides. In a logistic regression model only BMI and family history but not polymorphism were predictors of DM-2. CONCLUSIONS In conclusion, the present data suggest that in a German Caucasian population the Pro387Leu polymorphism of the PTP-1B gene is not associated with DM-2 but may play a role in other metabolic phenotypes.
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Affiliation(s)
- I Gouni-Berthold
- Department of Internal Medicine II, University of Cologne and Center of Molecular Medicine Cologne (CMMC), Cologne, Germany.
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von Eyben FE, Kroustrup JP, Larsen JF, Celis J. Comparison of Gene Expression in Intra-Abdominal and Subcutaneous Fat: A Study of Men with Morbid Obesity and Nonobese Men Using Microarray and Proteomics. Ann N Y Acad Sci 2004; 1030:508-36. [PMID: 15659836 DOI: 10.1196/annals.1329.063] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Extent of intra-abdominal fat had significant linear relations with six metabolic coronary risk factors: systolic and diastolic blood pressure, fasting blood concentrations of glucose, high density lipoprotein (HDL) cholesterol, triglyceride, and plasminogen activator inhibitor-1. Tumor necrosis factor-alpha and adiponectin can be biological mediators from the intra-abdominal fat to the metabolic coronary risk factors. Complementarily, we describe a new study that will analyze the gene expression in intra-abdominal and subcutaneous fat on mRNA and protein level using high throughput methods. The study will elucidate further whether intra-abdominal obesity is the common denominator for the different components of the metabolic syndrome.
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