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Hiraike Y, Tsutsumi S, Wada T, Oguchi M, Saito K, Nakamura M, Ota S, Koebis M, Nakao H, Aiba A, Nagano G, Ohno H, Oki K, Yoneda M, Kadowaki T, Aburatani H, Waki H, Yamauchi T. NFIA determines the cis-effect of genetic variation on Ucp1 expression in murinethermogenic adipocytes. iScience 2022; 25:104729. [PMID: 35874098 PMCID: PMC9304612 DOI: 10.1016/j.isci.2022.104729] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/17/2022] [Accepted: 07/01/2022] [Indexed: 11/04/2022] Open
Abstract
Thermogenic brown and beige adipocytes counteract obesity by enhancing energy dissipation via uncoupling protein-1 (Ucp1). However, the effect of genetic variation on these cells, a major source of disease susceptibility, has been less well studied. Here we examined beige adipocytes from obesity-prone C57BL/6J (B6) and obesity-resistant 129X1/SvJ (129) mouse strains and identified a cis-regulatory variant rs47238345 that is responsible for differential Ucp1 expression. The alternative T allele of rs47238345 at the Ucp1 -12kb enhancer in 129 facilitates the allele-specific binding of nuclear factor I-A (NFIA) to mediate allele-specific enhancer-promoter interaction and Ucp1 transcription. Furthermore, CRISPR-Cas9/Cpf1-mediated single nucleotide polymorphism (SNP) editing of rs47238345 resulted in increased Ucp1 expression. We also identified Lim homeobox protein 8 (Lhx8), whose expression is higher in 129 than in B6, as a trans-acting regulator of Ucp1 in mice and humans. These results demonstrate the cis- and trans-acting effects of genetic variation on Ucp1 expression that underlie phenotypic diversity. NFIA in adipocytes determines Ucp1 expression between obesity-prone and -resistant mouse strains Allele-specific binding of NFIA at the Ucp1 -12kb enhancer mediates differential Ucp1 expression Editing of a SNP at the Ucp1 -12kb enhancer is sufficient to increase Ucp1 in obesity-prone strain
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Affiliation(s)
- Yuta Hiraike
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan.,Division for Health Service Promotion, the University of Tokyo, Tokyo 113-0033, Japan
| | - Shuichi Tsutsumi
- Genome Science and Medicine Laboratory, Research Center for Advanced Science and Technology, the University of Tokyo, Tokyo 153-8904, Japan
| | - Takahito Wada
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan
| | - Misato Oguchi
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan
| | - Kaede Saito
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan
| | - Masahiro Nakamura
- Precision Health, Department of Bioengineering, Graduate School of Engineering, the University of Tokyo, Tokyo 113-8655, Japan
| | - Satoshi Ota
- Genome Science and Medicine Laboratory, Research Center for Advanced Science and Technology, the University of Tokyo, Tokyo 153-8904, Japan
| | - Michinori Koebis
- Laboratory of Animal Resources, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, the University of Tokyo, Tokyo 113-0033, Japan
| | - Harumi Nakao
- Laboratory of Animal Resources, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, the University of Tokyo, Tokyo 113-0033, Japan
| | - Atsu Aiba
- Laboratory of Animal Resources, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, the University of Tokyo, Tokyo 113-0033, Japan
| | - Gaku Nagano
- Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Haruya Ohno
- Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Kenji Oki
- Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Masayasu Yoneda
- Department of Molecular and Internal Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Takashi Kadowaki
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan.,Department of Prevention of Diabetes and Lifestyle-Related Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan.,Toranomon Hospital, Tokyo 105-8470, Japan
| | - Hiroyuki Aburatani
- Genome Science and Medicine Laboratory, Research Center for Advanced Science and Technology, the University of Tokyo, Tokyo 153-8904, Japan
| | - Hironori Waki
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan.,Department of Diabetes and Endocrinology, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Toshimasa Yamauchi
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Tokyo 113-8655, Japan
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Dinas PC, Nintou E, Vliora M, Pravednikova AE, Sakellariou P, Witkowicz A, Kachaev ZM, Kerchev VV, Larina SN, Cotton J, Kowalska A, Gkiata P, Bargiota A, Khachatryan ZA, Hovhannisyan AA, Antonosyan MA, Margaryan S, Partyka A, Bogdanski P, Szulinska M, Kregielska-Narozna M, Czepczyński R, Ruchała M, Tomkiewicz A, Yepiskoposyan L, Karabon L, Shidlovskii Y, Metsios GS, Flouris AD. Prevalence of uncoupling protein one genetic polymorphisms and their relationship with cardiovascular and metabolic health. PLoS One 2022; 17:e0266386. [PMID: 35482655 PMCID: PMC9049362 DOI: 10.1371/journal.pone.0266386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 03/18/2022] [Indexed: 11/18/2022] Open
Abstract
Contribution of UCP1 single nucleotide polymorphisms (SNPs) to susceptibility for cardiometabolic pathologies (CMP) and their involvement in specific risk factors for these conditions varies across populations. We tested whether UCP1 SNPs A-3826G, A-1766G, Ala64Thr and A-112C are associated with common CMP and their risk factors across Armenia, Greece, Poland, Russia and United Kingdom. This case-control study included genotyping of these SNPs, from 2,283 Caucasians. Results were extended via systematic review and meta-analysis. In Armenia, GA genotype and A allele of Ala64Thr displayed ~2-fold higher risk for CMP compared to GG genotype and G allele, respectively (p<0.05). In Greece, A allele of Ala64Thr decreased risk of CMP by 39%. Healthy individuals with A-3826G GG genotype and carriers of mutant allele of A-112C and Ala64Thr had higher body mass index compared to those carrying other alleles. In healthy Polish, higher waist-to-hip ratio (WHR) was observed in heterozygotes A-3826G compared to AA homozygotes. Heterozygosity of A-112C and Ala64Thr SNPs was related to lower WHR in CMP individuals compared to wild type homozygotes (p<0.05). Meta-analysis showed no statistically significant odds-ratios across our SNPs (p>0.05). Concluding, the studied SNPs could be associated with the most common CMP and their risk factors in some populations.
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Affiliation(s)
- Petros C. Dinas
- FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece
- Faculty of Education Health and Wellbeing, University of Wolverhampton, Walsall, West Midlands, United Kingdom
| | - Eleni Nintou
- FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece
| | - Maria Vliora
- FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece
| | - Anna E. Pravednikova
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Paraskevi Sakellariou
- FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece
| | - Agata Witkowicz
- L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Zaur M. Kachaev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Victor V. Kerchev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Svetlana N. Larina
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - James Cotton
- Royal Wolverhampton NHS Trust, New Cross Hospital, Wolverhampton, United Kingdom
| | - Anna Kowalska
- Institute of Human Genetics, Polish Academy of Sciences, Poznań, Poland
| | - Paraskevi Gkiata
- FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece
| | - Alexandra Bargiota
- Department of Endocrinology and Metabolic Diseases, Medical School, Larissa University Hospital, University of Thessaly, Larissa, Greece
| | - Zaruhi A. Khachatryan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, Yerevan, Armenia
| | - Anahit A. Hovhannisyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, Yerevan, Armenia
| | - Mariya A. Antonosyan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, Yerevan, Armenia
| | - Sona Margaryan
- Institute of Molecular Biology, National Academy of Sciences of the Republic of Armenia, Yerevan, Armenia
| | - Anna Partyka
- L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Pawel Bogdanski
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, Poznań, Poland
| | - Monika Szulinska
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, Poznań, Poland
| | - Matylda Kregielska-Narozna
- Department of Treatment of Obesity, Metabolic Disorders and Clinical Dietetics, Poznan University of Medical Sciences, Poznań, Poland
| | - Rafał Czepczyński
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Poznań, Poland
| | - Marek Ruchała
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, Poznań, Poland
| | - Anna Tomkiewicz
- L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Levon Yepiskoposyan
- Department of Bioengineering, Bioinformatics and Molecular Biology, Russian-Armenian University, Yerevan, Armenia
| | - Lidia Karabon
- L. Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Yulii Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - George S. Metsios
- Department of Nutrition and Dietetics, School of Physical Education, Sport Science and Dietetics, University of Thessaly, Trikala, Greece
| | - Andreas D. Flouris
- FAME Laboratory, Department of Physical Education and Sport Science, University of Thessaly, Trikala, Greece
- * E-mail:
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Diao Z, Murakami M, Sato R, Shimokawa F, Matsumura M, Hashimoto O, Onda K, Shirai M, Matsui T, Funaba M. Identification and expression of bovine Ucp1 variants. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159111. [DOI: 10.1016/j.bbalip.2022.159111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/05/2022] [Accepted: 01/12/2022] [Indexed: 10/19/2022]
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Tait BD. The importance of establishing genetic phase in clinical medicine. Int J Immunogenet 2021; 49:1-7. [PMID: 34958529 DOI: 10.1111/iji.12567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 11/15/2021] [Accepted: 11/19/2021] [Indexed: 12/27/2022]
Abstract
Haplotyping or determination of genetic phase has always played a pivotal role in MHC (HLA studies) both in helping to understand inheritance patterns in diseases such as type 1 diabetes (T1D) and in ensuring better matching in transplantation scenarios such as haematopoietic stem cell transplantation (HSCT), using donors genetically related to the patient. In recent years the need to establish genetic phase in a number of clinical scenarios has become apparent. These include: Genetic phasing for hematopoietic stem cell transplants using unrelated donors, where the HLA haplotypes are not known but where haplotype-matched recipients fare better clinically than allele matched, but haplotype mismatched patients. The use of checkpoint inhibitors is one of the most innovative and exciting developments in cancer treatment in years. An example is the use of the monoclonal ipilimumab to block the CTLA-4 receptor which is known to contain polymorphic sites. Until the phase of these polymorphisms is known it will not be possible to determine how effectively this monoclonal will perform in individual patients. The role of miRNA single strand molecules and their effect on gene expression. Thousands of non-coding genes have been identified and have been shown to be polymorphic, as have their target genes. Genetic phasing of polymorphism both in the miRNA source genes and their targets is clearly a fertile area of research In areas such a drug metabolism where the polymorphic family of CYP genes is responsible for the metabolism of the majority of prescription drugs, determining phase of SNPs is critical to understanding drug metabolism and efficacy. In multigenic disease studies combinations of single nucleotide polymorphisms (SNPs) in participating genes require accurate phasing in order to fully appreciate their role in the disease process. In addition, the level of expression of genes (point 3) is also important in understanding disease processes at the functional level. This review outlines the techniques that are currently available for approximating phase and discusses the clinical relevance of establishing genetic phase in areas of clinical medicine outlined in points 1-3.
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Affiliation(s)
- Brian D Tait
- Haplomic Technologies, Melbourne, Australia.,Department of Medicine, University of Melbourne, Royal Melbourne Hospital, Australia
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5
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Ethnicity Differences in the Association of UCP1-3826A/G, UCP2-866G/A and Ala55Val, and UCP3-55C/T Polymorphisms with Type 2 Diabetes Mellitus Susceptibility: An Updated Meta-Analysis. BIOMED RESEARCH INTERNATIONAL 2021; 2021:3482879. [PMID: 34712730 PMCID: PMC8548105 DOI: 10.1155/2021/3482879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/04/2021] [Indexed: 01/19/2023]
Abstract
Background The relationship between uncoupling protein (UCP) 1-3 polymorphisms and susceptibility to type 2 diabetes mellitus (T2DM) has been extensively studied, while conclusions remain contradictory. Thus, we performed this meta-analysis to elucidate whether the UCP1-3826A/G, UCP2-866G/A, Ala55Val, and UCP3-55C/T polymorphisms are associated with T2DM. Methods Eligible studies were searched from PubMed, Cochrane Library, and Web of Science database before 12 July 2020. Pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. Heterogeneity analysis, subgroup analysis, sensitivity analysis, and publication bias were also performed. Results A total of 38 case-control studies were included in this meta-analysis. The overall results revealed significant association between T2DM and the UCP2 Ala55Val polymorphism (recessive model: OR = 1.25, 95% CI 1.12-1.40, P < 0.01; homozygous model: OR = 1.33, 95% CI 1.03-1.72, P = 0.029, respectively). In subgroup analysis stratified by ethnicity, T2DM risk was increased with the UCP2 Ala55Val polymorphism (allele model: OR = 1.17, 95% CI 1.02-1.34, P = 0.023; recessive model: OR = 1.28, 95% CI 1.13-1.45, P < 0.01; homozygous model: OR = 1.39, 95% CI 1.05-1.86, P = 0.023, respectively), while decreased with the UCP2-866G/A polymorphism in Asians (dominant model: OR = 0.86, 95% CI 0.74-1.00, P = 0.045). Conclusions Our results demonstrate that the UCP2-866G/A polymorphism is protective against T2DM, while the UCP2 Ala55Val polymorphism is susceptible to T2DM in Asians.
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Pravednikova AE, Shevchenko SY, Kerchev VV, Skhirtladze MR, Larina SN, Kachaev ZM, Egorov AD, Shidlovskii YV. Association of uncoupling protein (Ucp) gene polymorphisms with cardiometabolic diseases. Mol Med 2020; 26:51. [PMID: 32450815 PMCID: PMC7249395 DOI: 10.1186/s10020-020-00180-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 05/11/2020] [Indexed: 12/23/2022] Open
Abstract
The hereditary aspect of obesity is a major focus of modern medical genetics. The genetic background is known to determine a higher-than-average prevalence of obesity in certain regions, like Oceania. There is evidence that dysfunction of brown adipose tissue (BAT) may be a risk factor for obesity and type 2 diabetes (T2D). A significant number of studies in the field focus on the UCP family. The Ucp genes code for electron transport carriers. UCP1 (thermogenin) is the most abundant protein of the UCP superfamily and is expressed in BAT, contributing to its capability of generating heat. Single nucleotide polymorphisms (SNPs) of Ucp1-Ucp3 were recently associated with risk of cardiometabolic diseases. This review covers the main Ucp SNPs A-3826G, A-1766G, A-112C, Met229Leu, Ala64Thr (Ucp1), Ala55Val, G-866A (Ucp2), and C-55 T (Ucp3), which may be associated with the development of obesity, disturbance in lipid metabolism, T2D, and cardiovascular diseases.
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Affiliation(s)
- Anna E. Pravednikova
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Sergey Y. Shevchenko
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Victor V. Kerchev
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Manana R. Skhirtladze
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Svetlana N. Larina
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Zaur M. Kachaev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander D. Egorov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Yulii V. Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
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Jin P, Li Z, Xu X, He J, Chen J, Xu X, Du X, Bai X, Zhang B, He X, Lu L, Zhu J, Shi Y, Zou H. Analysis of association between common variants of uncoupling proteins genes and diabetic retinopathy in a Chinese population. BMC MEDICAL GENETICS 2020; 21:25. [PMID: 32028915 PMCID: PMC7006419 DOI: 10.1186/s12881-020-0956-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 01/20/2020] [Indexed: 01/19/2023]
Abstract
BACKGROUND The aim of this study was to explore the association between diabetic retinopathy (DR) and the variants of uncoupling proteins (UCPs) genes in a Chinese population of type 2 diabetes, in total and in patients of different glycemic status separately. METHODS This case-control study included a total of 3107 participants from two datasets, among which 662 were DR patients (21.31%). Eighteen tag single nucleotide polymorphisms (SNPs) of UCP1, UCP2, and UCP3 were selected as genetic markers. TaqMan probes, Sequenom MassARRAY MALDI-TOF mass spectrometry platform and Affymetrix Genome-Wide Human SNP Array were used for genotyping. Online SHEsis software was used for association analysis. Bonferroni correction was used for multiple comparisons correction. RESULTS Three SNPs of UCP1: rs7688743 (A allele, OR = 1.192, p = 0.013), rs3811787 (T allele, OR = 0.863, p = 0.023), and rs10011540 (G allele, OR = 1.368, p = 0.004) showed association with DR after the adjustment of glucose, but only rs10011540 was marginally significantly associated with DR when Bonferroni correction was strictly applied (padj = 0.048). In patients with uncontrolled glucose, rs7688743 (A allele, p = 0.012, OR = 1.309), rs10011540 (G allele, p = 0.033, OR = 1.432), and rs3811787 (T allele, p = 0.022, OR = 0.811) were associated with DR, while in participants with well controlled glucose, the rs2734827 of UCP3 was associated with DR (A allele, p = 0.017, OR = 0.532). Rs3811787 of UCP1 showed a protective effect to sight threatening DR (T allele, p = 0.007, OR = 0.490), and the association existed after the adjustment for environmental factors and the correction. In patients with uncontrolled glucose, the rs3811787 of UCP1 (T allele, p = 0.017, OR = 0.467) and the rs591758 of UCP3 (C allele, p = 0.026, OR = 0.103) were associated with STDR. While in those with well controlled glucose, only the rs7688743 of UCP1 showed a protective effect (A allele, p = 0.024, OR = 0.049). None of the associations remain significant when Bonferroni correction was strictly applied (all p < 0.05). CONCLUSIONS The rs10011540 and rs3811787 of the UCP1 gene was marginally significantly associated with DR in Chinese type 2 diabetes patients. There might be different mechanisms of DR development in patients with different glycemic status.
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Affiliation(s)
- Peiyao Jin
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine (originally named"Shanghai First People's Hospital"), Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, National Clinical Research Center for Eye Diseases, No.100 Haining Road, Shanghai, 20080, China
| | - Zhiqiang Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Xian Xu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine (originally named"Shanghai First People's Hospital"), Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, National Clinical Research Center for Eye Diseases, No.100 Haining Road, Shanghai, 20080, China
| | - Jiangnan He
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Jianhua Chen
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Xun Xu
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine (originally named"Shanghai First People's Hospital"), Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, National Clinical Research Center for Eye Diseases, No.100 Haining Road, Shanghai, 20080, China.,Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Xuan Du
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Xuelin Bai
- Xinjing Community Health Service Centre, Shanghai, 200335, China
| | - Bo Zhang
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Xiangui He
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Lina Lu
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Jianfeng Zhu
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China
| | - Yongyong Shi
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Haidong Zou
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine (originally named"Shanghai First People's Hospital"), Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, National Clinical Research Center for Eye Diseases, No.100 Haining Road, Shanghai, 20080, China. .,Shanghai Eye Disease Prevention and Treatment Center, Shanghai Eye Hospital, Shanghai, 200040, China.
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Lu WH, Chang YM, Huang YS. Alternative Polyadenylation and Differential Regulation of Ucp1: Implications for Brown Adipose Tissue Thermogenesis Across Species. Front Pediatr 2020; 8:612279. [PMID: 33634052 PMCID: PMC7899972 DOI: 10.3389/fped.2020.612279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/30/2020] [Indexed: 12/12/2022] Open
Abstract
Brown adipose tissue (BAT) is a thermogenic organ owing to its unique expression of uncoupling protein 1 (UCP1), which is a proton channel in the inner mitochondrial membrane used to dissipate the proton gradient and uncouple the electron transport chain to generate heat instead of adenosine triphosphate. The discovery of metabolically active BAT in human adults, especially in lean people after cold exposure, has provoked the "thermogenic anti-obesity" idea to battle weight gain. Because BAT can expend energy through UCP1-mediated thermogenesis, the molecular mechanisms regulating UCP1 expression have been extensively investigated at both transcriptional and posttranscriptional levels. Of note, the 3'-untranslated region (3'-UTR) of Ucp1 mRNA is differentially processed between mice and humans that quantitatively affects UCP1 synthesis and thermogenesis. Here, we summarize the regulatory mechanisms underlying UCP1 expression, report the number of poly(A) signals identified or predicted in Ucp1 genes across species, and discuss the potential and caution in targeting UCP1 for enhancing thermogenesis and metabolic fitness.
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Affiliation(s)
- Wen-Hsin Lu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yao-Ming Chang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yi-Shuian Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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Chathoth S, Ismail MH, Vatte C, Cyrus C, Al Ali Z, Ahmed KA, Acharya S, Al Barqi AM, Al Ali A. Association of Uncoupling Protein 1 (UCP1) gene polymorphism with obesity: a case-control study. BMC MEDICAL GENETICS 2018; 19:203. [PMID: 30458724 PMCID: PMC6247512 DOI: 10.1186/s12881-018-0715-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 11/08/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Obesity is one of the main causes of morbidity and mortality worldwide. More than 120 genes have been shown to be associated with obesity related phenotypes. The aim of this study was to determine the effect of selected genetic polymorphisms in Uncoupling protein 1 (UCP1) and Niemann-Pick C1 (NPC1) genes in an obese population in Saudi Arabia. METHODS The genotypes of rs1800592, rs10011540 and rs3811791 (UCP1 gene) and rs1805081 and rs1805082 (NPC1 gene) were determined in a total of 492 subjects using TaqMan chemistry by Real-time PCR. In addition, capillary sequencing assay was performed to identify two specific polymorphisms viz., rs45539933 (exon 2) and rs2270565 (exon 5) of UCP1 gene. RESULTS A significant association of UCP1 polymorphisms rs1800592 [OR, 1.52 (1.10-2.08); p = 0.009] was observed in the obese cohort after adjusting with age, sex and type 2 diabetes. Further BMI based stratification revealed that this association was inconsistent with both moderate and extreme obese cohort. A significant association of UCP1 polymorphisms rs3811791 was observed only in the moderate-obese cohort [OR = 2.89 (1.33-6.25); p = 0.007] but not in the extreme-obese cohort indicating an overlying genetic complexity between moderate-obesity and extreme-obesity. The risk allele frequencies, which were higher in moderate-obese cohort, had abnormal HDL, LDL and triglyceride levels. CONCLUSION The rs1800592 and rs3811791 of UCP1 gene are associated with obesity in general and in the moderate-obese group in particular. The associated UCP1 polymorphisms in the moderate-obese group may regulate the impaired energy metabolism which plays a significant role in the initial stages of obesity.
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Affiliation(s)
- Shahanas Chathoth
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam, 31441 Saudi Arabia
| | - Mona H. Ismail
- Department of Internal Medicine, King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Al-Khobar, Saudi Arabia
| | - Chittibabu Vatte
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam, 31441 Saudi Arabia
| | - Cyril Cyrus
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam, 31441 Saudi Arabia
| | - Zhara Al Ali
- Department of Internal Medicine, King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Al-Khobar, Saudi Arabia
| | | | - Sadananda Acharya
- Department of Public Health, College of Public Health, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Aisha Mohammed Al Barqi
- Department of Internal Medicine, King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Al-Khobar, Saudi Arabia
| | - Amein Al Ali
- Department of Biochemistry, Imam Abdulrahman Bin Faisal University, Dammam, 31441 Saudi Arabia
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Sequence and Haplotypes Variation of the Ovine Uncoupling Protein-1 Gene (UCP1) and Their Association with Growth and Carcass Traits in New Zealand Romney Lambs. Genes (Basel) 2018; 9:genes9040189. [PMID: 29601527 PMCID: PMC5924531 DOI: 10.3390/genes9040189] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/12/2018] [Accepted: 03/28/2018] [Indexed: 11/21/2022] Open
Abstract
Uncoupling protein-1 gene (UCP1) plays an important role in the regulation of thermogenesis, energy expenditure, and protection against oxidative stress. In this study, six separate UCP1 regions: region-1 and region-2 (two parts of the promoter), region-3 and region-4 (two parts of intron 1), region-5 (spanning part of intron 5 and part of exon 6), and region-6 (spanning part of exon 6 and part of the 3′-UTR) from a variety of sheep breeds, were analysed using polymerase chain reaction-single-stranded conformational polymorphism (PCR-SSCP) analyses. In total, 30 single nucleotide polymorphisms (SNPs) were detected. Of these, 14 were located in the promoter, eight were found in intron 1, six were found in intron 5, and one was found in the 3′-UTR. One substitution in exon 6 (c.910A/G) would putatively result in an amino acid change (p.Thr304Ala). Twenty-eight novel SNPs and nine new haplotypes spanning region-2 to region-5 were identified. Of these nine haplotypes, five were common (B2-A5, C2-A5, C2-C5, A2-A5, and A2-B5) and four were rare (C2-B5, A2-C5, B2-C5, and B2-B5) in the sheep investigated. Of the five common haplotypes found in 314 New Zealand Romney sheep for which growth and carcass trait data were available, the presence of A2-B5 was associated with decreased hot carcass weight (HCW) and loin lean-meat yield (p = 0.006, p = 0.032, respectively), and the presence of C2-C5 was associated with a decreased proportion of leg lean-meat yield (p = 0.047) in the carcasses. No associations were found with growth traits. These results confirm that ovine UCP1 is a variable gene and may have value as a genetic marker for sheep breeding.
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Brondani LDA, Assmann TS, Duarte GCK, Gross JL, Canani LH, Crispim D. The role of the uncoupling protein 1 (UCP1) on the development of obesity and type 2 diabetes mellitus. ACTA ACUST UNITED AC 2013; 56:215-25. [PMID: 22790465 DOI: 10.1590/s0004-27302012000400001] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 06/10/2012] [Indexed: 12/19/2022]
Abstract
It is well established that genetic factors play an important role in the development of both type 2 diabetes mellitus (DM2) and obesity, and that genetically susceptible subjects can develop these metabolic diseases after being exposed to environmental risk factors. Therefore, great efforts have been made to identify genes associated with DM2 and/or obesity. Uncoupling protein 1 (UCP1) is mainly expressed in brown adipose tissue, and acts in thermogenesis, regulation of energy expenditure, and protection against oxidative stress. All these mechanisms are associated with the pathogenesis of DM2 and obesity. Hence, UCP1 is a candidate gene for the development of these disorders. Indeed, several studies have reported that polymorphisms -3826A/G, -1766A/G and -112A/C in the promoter region, Ala64Thr in exon 2 and Met299Leu in exon 5 of UCP1 gene are possibly associated with obesity and/or DM2. However, results are still controversial in different populations. Thus, the aim of this study was to review the role of UCP1 in the development of these metabolic diseases.
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Affiliation(s)
- Letícia de Almeida Brondani
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, RS, Brazil
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12
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de Souza BM, Brondani LA, Bouças AP, Sortica DA, Kramer CK, Canani LH, Leitão CB, Crispim D. Associations between UCP1 -3826A/G, UCP2 -866G/A, Ala55Val and Ins/Del, and UCP3 -55C/T polymorphisms and susceptibility to type 2 diabetes mellitus: case-control study and meta-analysis. PLoS One 2013; 8:e54259. [PMID: 23365654 PMCID: PMC3554780 DOI: 10.1371/journal.pone.0054259] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 12/10/2012] [Indexed: 12/30/2022] Open
Abstract
Background Some studies have reported associations between five uncoupling protein (UCP) 1–3 polymorphisms and type 2 diabetes mellitus (T2DM). However, other studies have failed to confirm the associations. This paper describes a case-control study and a meta-analysis conducted to attempt to determine whether the following polymorphisms are associated with T2DM: -3826A/G (UCP1); -866G/A, Ala55Val and Ins/Del (UCP2) and -55C/T (UCP3). Methods The case-control study enrolled 981 T2DM patients and 534 nondiabetic subjects, all of European ancestry. A literature search was run to identify all studies that investigated associations between UCP1–3 polymorphisms and T2DM. Pooled odds ratios (OR) were calculated for allele contrast, additive, recessive, dominant and co-dominant inheritance models. Sensitivity analyses were performed after stratification by ethnicity. Results In the case-control study the frequencies of the UCP polymorphisms did not differ significantly between T2DM and nondiabetic groups (P>0.05). Twenty-three studies were eligible for the meta-analysis. Meta-analysis results showed that the Ala55Val polymorphism was associated with T2DM under a dominant model (OR = 1.27, 95% CI 1.03–1.57); while the -55C/T polymorphism was associated with this disease in almost all genetic models: allele contrast (OR = 1.17, 95% CI 1.02–1.34), additive (OR = 1.32, 95% CI 1.01–1.72) and dominant (OR = 1.18, 95% CI 1.02–1.37). However, after stratification by ethnicity, the UCP2 55Val and UCP3 -55C/T alleles remained associated with T2DM only in Asians (OR = 1.25, 95% CI 1.02–1.51 and OR = 1.22, 95% CI 1.04–1.44, respectively; allele contrast model). No significant association of the -3826A/G, -866G/A and Ins/Del polymorphisms with T2DM was observed. Conclusions In our case-control study of people with European ancestry we were not able to demonstrate any association between the UCP polymorphisms and T2DM; however, our meta-analysis detected a significant association between the UCP2 Ala55Val and UCP3 -55C/T polymorphisms and increased susceptibility for T2DM in Asians.
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Affiliation(s)
- Bianca M. de Souza
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
| | - Letícia A. Brondani
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
| | - Ana P. Bouças
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
| | - Denise A. Sortica
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
| | - Caroline K. Kramer
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Luís H. Canani
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
| | - Cristiane B. Leitão
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
| | - Daisy Crispim
- Endocrinology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Postgraduate Program in Medical Sciences: Endocrinology, Universidade Federal do Rio Grande do Sul. Porto Alegre, Rio Grande do Sul, Brazil
- * E-mail:
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Cloning and ontogenetic expression of the uncoupling protein 1 gene UCP1 in sheep. J Appl Genet 2012; 53:203-12. [DOI: 10.1007/s13353-012-0086-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 01/26/2012] [Accepted: 01/26/2012] [Indexed: 12/19/2022]
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14
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Yao X, Shan S, Zhang Y, Ying H. Recent progress in the study of brown adipose tissue. Cell Biosci 2011; 1:35. [PMID: 22035495 PMCID: PMC3219668 DOI: 10.1186/2045-3701-1-35] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 10/28/2011] [Indexed: 01/11/2023] Open
Abstract
Brown adipose tissue in mammals plays a critical role in maintaining energy balance by thermogenesis, which means dissipating energy in the form of heat. It is held that in mammals, long-term surplus food intake results in energy storage in the form of triglyceride and may eventually lead to obesity. Stimulating energy-dissipating function of brown adipose tissue in human body may counteract fat accumulation. In order to utilize brown adipose tissue as a therapeutic target, the mechanisms underlying brown adipocyte differentiation and function should be better elucidated. Here we review the molecular mechanisms involved in brown adipose tissue development and thermogenesis, and share our thoughts on current challenges and possible future therapeutic approaches.
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Affiliation(s)
- Xuan Yao
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
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15
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Rose G, Crocco P, D'Aquila P, Montesanto A, Bellizzi D, Passarino G. Two variants located in the upstream enhancer region of human UCP1 gene affect gene expression and are correlated with human longevity. Exp Gerontol 2011; 46:897-904. [PMID: 21827845 DOI: 10.1016/j.exger.2011.07.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 05/31/2011] [Accepted: 07/24/2011] [Indexed: 11/25/2022]
Abstract
The brown fat specific UnCoupling Protein 1 (UCP1) is involved in thermogenesis, a process by which energy is dissipated as heat in response to cold stress and excess of caloric intake. Thermogenesis has potential implications for body mass control and cellular fat metabolism. In fact, in humans, the variability of the UCP1 gene is associated with obesity, fat gain and metabolism. Since regulation of metabolism is one of the key-pathways in lifespan extension, we tested the possible effects of UCP1 variability on survival. Two polymorphisms (A-3826G and C-3740A), falling in the upstream promoter region of UCP1, were analyzed in a sample of 910 subjects from southern Italy (475 women and 435 men; age range 40-109). By analyzing haplotype specific survival functions we found that the A-C haplotype favors survival in the elderly. Consistently, transfection experiments showed that the luciferase activity of the construct containing the A-C haplotype was significantly higher than that containing the G-A haplotype. Interestingly, the different UCP1 haplotypes responded differently to hormonal stimuli. The results we present suggest a correlation between the activity of UCP1 and human survival, indicating once again the intricacy of mechanisms involved in energy production, storage and consumption as the key to understanding human aging and longevity.
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Affiliation(s)
- Giuseppina Rose
- Department of Cell Biology, University of Calabria, Rende, Italy.
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Labruna G, Pasanisi F, Fortunato G, Nardelli C, Finelli C, Farinaro E, Contaldo F, Sacchetti L. Sequence Analysis of the UCP1 Gene in a Severe Obese Population from Southern Italy. J Obes 2011; 2011:269043. [PMID: 21773003 PMCID: PMC3136174 DOI: 10.1155/2011/269043] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Accepted: 04/08/2011] [Indexed: 02/07/2023] Open
Abstract
Brown adipose tissue, where Uncoupling Protein 1 (UCP1) activity uncouples mitochondrial respiration, is an important site of facultative energy expenditure. This tissue may normally function to prevent obesity. Our aim was to investigate by sequence analysis the presence of UCP1 gene variations that may be associated with obesity. We studied 100 severe obese adults (BMI > 40 kg/m(2)) and 100 normal-weight control subjects (BMI range = 19-24.9 kg/m(2)). We identified 7 variations in the promoter region, 4 in the intronic region and 4 in the exonic region. Globally, 72% of obese patients bore UCP1 polymorphisms. Among UCP1 variants, g.IVS4-208T>G SNP was associated with obesity (OR: 1.77; 95% CI = 1.26-2.50; P = .001). Further, obese patients bearing the g.-451C>T (CT+TT) or the g.940G>A (GA+AA) genotypes showed a higher BMI than not polymorphic obese patients (P = .008 and P = .043, resp.). In conclusion, UCP1 SNPs could represent "thrifty" factors that promote energy storage in prone subjects.
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Affiliation(s)
- Giuseppe Labruna
- Fondazione IRCCS SDN, Istituto di Ricerca Diagnostica e Nucleare, Via Gianturco 113, 80143 Naples, Italy
| | - Fabrizio Pasanisi
- Centro Interuniversitario di Studi e Ricerche sull'Obesità e Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Napoli Federico II, Via Pansini 5, 80131 Naples, Italy
| | - Giuliana Fortunato
- CEINGE Biotecnologie Avanzate S.C. a R.L., Via Gaetano Salvatore 486, 80145, Naples, Italy
- Dipartimento di Biochimica e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Pansini 5, Via Pansini 5, 80131 Naples, Italy
| | - Carmela Nardelli
- CEINGE Biotecnologie Avanzate S.C. a R.L., Via Gaetano Salvatore 486, 80145, Naples, Italy
- Dipartimento di Biochimica e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Pansini 5, Via Pansini 5, 80131 Naples, Italy
| | - Carmine Finelli
- Fondazione Stella Maris Mediterraneo, Centro Disturbi del Comportamento Alimentare e del Peso “G. Gioia”, Chiaromonte, C/da S. Lucia, 85100, Chiaromonte, Potenza, Italy
| | - Eduardo Farinaro
- Dipartimento di Scienze Mediche Preventive, Università degli Studi di Napoli Federico II, Via Pansini 5, 80131 Naples, Italy
| | - Franco Contaldo
- Centro Interuniversitario di Studi e Ricerche sull'Obesità e Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Napoli Federico II, Via Pansini 5, 80131 Naples, Italy
| | - Lucia Sacchetti
- CEINGE Biotecnologie Avanzate S.C. a R.L., Via Gaetano Salvatore 486, 80145, Naples, Italy
- Dipartimento di Biochimica e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Via Pansini 5, Via Pansini 5, 80131 Naples, Italy
- *Lucia Sacchetti:
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Vimaleswaran KS, Radha V, Ghosh S, Majumder PP, Rao MRS, Mohan V. A haplotype at the UCP1 gene locus contributes to genetic risk for type 2 diabetes in Asian Indians (CURES-72). Metab Syndr Relat Disord 2010; 8:63-8. [PMID: 19943796 DOI: 10.1089/met.2009.0039] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The gene encoding for uncoupling protein-1 (UCP1) is considered to be a candidate gene for type 2 diabetes because of its role in thermogenesis and energy expenditure. The objective of the study was to examine whether genetic variations in the UCP1 gene are associated with type 2 diabetes and its related traits in Asian Indians. METHODS The study subjects, 810 type 2 diabetic subjects and 990 normal glucose tolerant (NGT) subjects, were chosen from the Chennai Urban Rural Epidemiological Study (CURES), an ongoing population-based study in southern India. The polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Linkage disequilibrium (LD) was estimated from the estimates of haplotypic frequencies. RESULTS The three polymorphisms, namely -3826A-->G, an A-->C transition in the 5'-untranslated region (UTR) and Met229Leu, were not associated with type 2 diabetes. However, the frequency of the A-C-Met (-3826A-->G-5'UTR A-->C-Met229Leu) haplotype was significantly higher among the type 2 diabetic subjects (2.67%) compared with the NGT subjects (1.45%, P < 0.01). The odds ratio for type 2 diabetes for the individuals carrying the haplotype A-C-Met was 1.82 (95% confidence interval, 1.29-2.78, P = 0.009). CONCLUSIONS The haplotype, A-C-Met, in the UCP1 gene is significantly associated with the increased genetic risk for developing type 2 diabetes in Asian Indians.
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Kozak LP, Koza RA. The genetics of brown adipose tissue. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 94:75-123. [PMID: 21036323 DOI: 10.1016/b978-0-12-375003-7.00004-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Brown adipose tissue is highly differentiated and has evolved as a mechanism for heat production based upon uncoupling of mitochondrial oxidative phosphorylation. Additionally, large amounts of lipid can be stored in the cells to provide fuel necessary for heat production upon adrenergic stimulation from the central nervous system, and a highly developed vascular system evolved to rapidly deliver heat to vital organs. For unknown reasons, the development of brown adipocytes has two independent pathways: one originates from muscle progenitor cells in the fetus and leads to a fully functional cell at birth (interscapular-type brown fat), while the other transiently emerges in traditional white fat depots at weaning, regresses, and then can be induced in adult mice upon adrenergic stimulation. No genetic variants have been found for interscapular fat, but naturally occurring alleles at eight genetic loci in mice lead to over 100-fold variation for brown adipocytes in white fat upon adrenergic stimulation. The ability to activate this potential for energy expenditure is of great interest in obesity research.
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Affiliation(s)
- Leslie P Kozak
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, USA
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The polymorphisms of UCP1 genes associated with fat metabolism, obesity and diabetes. Mol Biol Rep 2009; 37:1513-22. [PMID: 19444646 DOI: 10.1007/s11033-009-9550-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Accepted: 04/30/2009] [Indexed: 10/20/2022]
Abstract
Uncoupling protein 1 (UCP1), a 32-kDa protein located in the inner mitochondrial membrane, is abundant in brown adipose tissue, as a proton transporter in mitochondria inner membrane which uncouples oxidative metabolism from ATP synthesis and dissipates energy through the heat. UCP1 has been reported to play important roles for energy homeostasis in rodents and neonate of larger mammals including human. Recently, numerous candidate genes were searched to determine the genetic factors implicated in the pathogenesis of obesity, related metabolic disorders and diabetes. UCP-1, which plays a major role in thermogenesis, was suggested to be one of the candidates. This review summarizes data supporting the existence of brown adipocytes and the role of UCP1 in energy dissipation in adult humans, and the genetic variety association with the fat metabolism, obesity and diabetes.
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Tiwari AK, Prasad P, B K T, Kumar KMP, Ammini AC, Gupta A, Gupta R. Oxidative stress pathway genes and chronic renal insufficiency in Asian Indians with Type 2 diabetes. J Diabetes Complications 2009; 23:102-11. [PMID: 18413200 DOI: 10.1016/j.jdiacomp.2007.10.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Revised: 07/16/2007] [Accepted: 10/18/2007] [Indexed: 12/13/2022]
Abstract
BACKGROUND There are significant regional variations in prevalence of diabetes and diabetic chronic renal insufficiency (CRI) in India. Oxidative stress plays an important role in the development of diabetic complications. To determine the importance of the polymorphisms in the genes involved in maintenance of cellular redox balance, we performed a case control study in subjects from south and north India. METHODS Successive cases presenting to the study centers with Type 2 diabetes of >2 years duration and moderate CRI (n=194, south India 104, north India 90) diagnosed by serum creatinine >or=2 mg/dl after exclusion of nondiabetic causes of CRI were compared with diabetes subjects with no evidence of renal disease (n=224, south India 149, north India 75). Twenty-six polymorphisms from 13 genes from the oxidative stress pathway were analyzed using polymerase chain reaction-restriction fragment length polymorphism. Genes included were superoxide dismutases (SOD1, 2, 3), uncoupling proteins (UCP1, 2), endothelial nitric oxide synthase (NOS3), glutathione-S-transferases (GST) (M1, T1, P1), vascular endothelial growth factor (VEGF), paraoxonase (PON) 1 and 2, and nicotinamide adenine dinucleotide phosphate reduced, oxidase p22(phox). Genes were tested for their association with CRI using chi(2) test. RESULTS In south Indian (SI) subjects there was significant allelic and genotypic association of the wild-type allele in SOD2 (Ala9Val; P=.002 and P=.013, respectively), UCP1 (-112 T>G, P=.012 and P=.009; Ala64Thr, P=.015 and P=.004), NOS3 (Glu298Asp, P=.002 and P=.009) and GSTP1 (Ile105Val, P=.003 and P=.004) genes with development of CRI. None of these observations were replicated in the north Indian (NI) subjects. A genotypic but not allelic association was observed for two markers, VEGF (-460 T>C) and PON1 (Arg192Gly) among NI diabetic CRI subjects. CONCLUSION The nonreplication of association suggests differential genetic susceptibility of the two populations to diabetic chronic renal insufficiency. In the SI diabetic subjects, oxidative stress pathway genes might be an important predictor for the development of diabetic complications. Further, the association of wild-type alleles may suggest that they confer greater survival ability to comorbid complications and may be nephroprotective.
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Affiliation(s)
- Arun K Tiwari
- Department of Genetics, University of Delhi South Campus, New Delhi 110 021, India
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Abstract
Mitochondrial uncoupling protein 1 (UCP1) is a key regulator of adaptive thermogenesis and energy expenditure. Mice lacking UCP1 are cold sensitive, but surprisingly not obese at room temperature. In this issue of Cell Metabolism, Feldmann et al. (2009) unmask an obesogenic phenotype by simply maintaining these mice at thermoneutrality.
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Vimaleswaran K, Radha V, Deepa R, Mohan V. Absence of Association of Metabolic Syndrome with PPARGC1A, PPARG and UCP1 Gene Polymorphisms in Asian Indians. Metab Syndr Relat Disord 2007; 5:153-62. [DOI: 10.1089/met.2006.0032] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- K.S. Vimaleswaran
- Madras Diabetes Research Foundation, Dr. Mohan's Diabetes Specialities Centre, Chennai, India
| | - V. Radha
- Madras Diabetes Research Foundation, Dr. Mohan's Diabetes Specialities Centre, Chennai, India
| | - R. Deepa
- Madras Diabetes Research Foundation, Dr. Mohan's Diabetes Specialities Centre, Chennai, India
| | - V. Mohan
- Madras Diabetes Research Foundation, Dr. Mohan's Diabetes Specialities Centre, Chennai, India
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Sale MM, Hsu FC, Palmer ND, Gordon CJ, Keene KL, Borgerink HM, Sharma AJ, Bergman RN, Taylor KD, Saad MF, Norris JM. The uncoupling protein 1 gene, UCP1, is expressed in mammalian islet cells and associated with acute insulin response to glucose in African American families from the IRAS Family Study. BMC Endocr Disord 2007; 7:1. [PMID: 17397545 PMCID: PMC1852562 DOI: 10.1186/1472-6823-7-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Accepted: 03/30/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Variants of uncoupling protein genes UCP1 and UCP2 have been associated with a range of traits. We wished to evaluate contributions of known UCP1 and UCP2 variants to metabolic traits in the Insulin Resistance and Atherosclerosis (IRAS) Family Study. METHODS We genotyped five promoter or coding single nucleotide polymorphisms (SNPs) in 239 African American (AA) participants and 583 Hispanic participants from San Antonio (SA) and San Luis Valley. Generalized estimating equations using a sandwich estimator of the variance and exchangeable correlation to account for familial correlation were computed for the test of genotypic association, and dominant, additive and recessive models. Tests were adjusted for age, gender and BMI (glucose homeostasis and lipid traits), or age and gender (obesity traits), and empirical P-values estimated using a gene dropping approach. RESULTS UCP1 A-3826G was associated with AIR(g) in AA (P = 0.006) and approached significance in Hispanic families (P = 0.054); and with HDL-C levels in SA families (P = 0.0004). Although UCP1 expression is reported to be restricted to adipose tissue, RT-PCR indicated that UCP1 is expressed in human pancreas and MIN-6 cells, and immunohistochemistry demonstrated co-localization of UCP1 protein with insulin in human islets. UCP2 A55V was associated with waist circumference (P = 0.045) in AA, and BMI in SA (P = 0.018); and UCP2 G-866A with waist-to-hip ratio in AA (P = 0.016). CONCLUSION This study suggests a functional variant of UCP1 contributes to the variance of AIR(g) in an AA population; the plausibility of this unexpected association is supported by the novel finding that UCP1 is expressed in islets.
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Affiliation(s)
- Michèle M Sale
- Center for Human Genomics, Wake Forest University School of Medicine, Winston-Salem, USA.
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Ioannidis JPA, Kavvoura FK. Concordance of functional in vitro data and epidemiological associations in complex disease genetics. Genet Med 2006; 8:583-93. [PMID: 16980815 DOI: 10.1097/01.gim.0000237775.93658.0c] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
PURPOSE We aimed to assess whether epidemiological evidence on genetic associations for complex diseases concord with in vitro functional data. METHODS We examined 36 studies on bi-allelic markers and 23 studies on haplotypes where investigators had addressed both epidemiological associations and the functional effect of the same gene variants in luciferase reporter systems in vitro. RESULTS There was no correlation between epidemiological odds ratios and luciferase activity ratios (-0.09, P = 0.60). Luciferase activity ratios could not tell whether a probed epidemiologic association would be significant or not (area under receiver operating characteristics curve, 0.52). Luciferase results usually were qualitatively similar across cell lines and experimental conditions, with some exceptions. A luciferase activity ratio of 1.44 adequately separated statistically significant from non-significant functional differences (area under receiver operating characteristics curve, 0.95). Binary and continuous disease outcomes usually gave concordant results; other in vitro methods, in particular EMSA, agreed with luciferase results. Selective reporting and use of different variants and contrasts between functional and epidemiological analyses were common in these studies. CONCLUSIONS In vitro biological data and epidemiology provide independent lines of evidence on complex diseases. We provide suggestions for improving the design and reporting of studies addressing both in vitro and epidemiological effects.
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Affiliation(s)
- John P A Ioannidis
- Clinical and Molecular Epidemiology Unit, Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina 45110, Greece
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Fukuyama K, Ohara T, Hirota Y, Maeda K, Kuno SI, Zenibayashi M, Teranishi T, Kouyama K, Maeda E, Sakamoto N, Kasuga M. Association of the -112A>C polymorphism of the uncoupling protein 1 gene with insulin resistance in Japanese individuals with type 2 diabetes. Biochem Biophys Res Commun 2005; 339:1212-6. [PMID: 16338218 DOI: 10.1016/j.bbrc.2005.11.140] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Accepted: 11/22/2005] [Indexed: 01/14/2023]
Abstract
The -112A>C polymorphism (rs10011540) of the gene for uncoupling protein 1 (UCP1) has been associated with type 2 diabetes mellitus in Japanese individuals. The aim of the present study was to investigate the effects of this polymorphism, as well as the well-known -3826A>G polymorphism (rs1800592), on clinical characteristics of type 2 diabetes. We determined the genotypes of the two polymorphisms in 93 Japanese patients with type 2 diabetes. Intramyocellular lipid content and hepatic lipid content (HLC) were measured by magnetic resonance spectroscopy. No significant differences in age, sex, BMI, or HbA1c level were detected between type 2 diabetic patients with the -112C allele and those without it. However, homeostasis model assessment for insulin resistance (p=0.0089) and HLC (p=0.012) was significantly greater in patients with the -112C allele. We did not detect an association of the -3826A>G polymorphism (rs1800592) of UCP1 gene with any measured parameters. These results suggest that insulin resistance caused by the -112C allele influences the susceptibility to type 2 diabetes.
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Affiliation(s)
- Keiko Fukuyama
- Division of Diabetes and Digestive and Kidney Diseases, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
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Valverde AM, Benito M, Lorenzo M. The brown adipose cell: a model for understanding the molecular mechanisms of insulin resistance. ACTA ACUST UNITED AC 2005; 183:59-73. [PMID: 15654920 DOI: 10.1111/j.1365-201x.2004.01384.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Type 2 diabetes mellitus is a complex metabolic disease that occurs when insulin secretion can no longer compensate insulin resistance in peripheral tissues. At the molecular level, insulin resistance correlates with impaired insulin signalling. This review provides new insights into the molecular mechanisms of insulin action and resistance in brown adipose tissue and pinpoints the role of this tissue in the control of glucose homeostasis. Brown adipocytes are target cells for insulin and IGF-I action, especially during late foetal development when insulin supports survival and promotes both adipogenic and thermogenic differentiation. The main pathway involved in insulin induction of adipogenic differentiation, monitored by fatty acid synthase expression, is the cascade insulin receptor substrate (IRS)-1/phosphatidylinositol 3-kinase (PI3K)/Akt. Glucose transport in these cells is maintained mainly by the activity of GLUT4. Acute insulin treatment stimulates glucose transport largely by mediating translocation of GLUT4 to the plasma membrane, involving the activation of IRS-2/PI3K, and the downstream targets Akt and protein kinase C zeta. Tumour necrosis factor (TNF-alpha) caused insulin resistance on glucose uptake by impairing insulin signalling at the level of IRS-2. Activation of stress kinases and phosphatases by this cytokine contribute to insulin resistance. Furthermore, brown adipocytes are also target cells for rosiglitazone action since they show a high expression of peroxisome proliferator activated receptor gamma, and rosiglitazone increased the expression of the thermogenic uncoupling protein 1. Rosiglitazone ameliorates insulin resistance provoked by TNF-alpha, completely restoring insulin-stimulated glucose uptake in parallel to the insulin signalling cascade. Accordingly, foetal brown adipocytes represent a model for investigating insulin action, as well as for the mechanism by which rosiglitazone increase insulin sensitivity under situations that mimic insulin resistance.
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Affiliation(s)
- A M Valverde
- Instituto de Bioquimica. Centro Mixto CSIC/UCM, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain
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Abstract
There are more than 430 chromosomic regions with gene variants involved in body weight regulation and obesity development. Polymorphisms in genes related to energy expenditure--uncoupling proteins (UCPs), related to adipogenesis and insulin resistance--hormone-sensitive lipase (HLS), peroxisome proliferator-activated receptor gamma (PPAR gamma), beta adrenergic receptors (ADRB2,3), and alfa tumor necrosis factor (TNF-alpha), and related to food intake--ghrelin (GHRL)--appear to be associated with obesity phenotypes. Obesity risk depends on two factors: a) genetic variants in candidate genes, and b) biographical exposure to environmental risk factors. It is necessary to perform new studies, with appropriate control groups and designs, in order to reach relevant conclusions with regard to gene/environmental (diet, lifestyle) interactions.
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Daimon M, Ji G, Saitoh T, Oizumi T, Tominaga M, Nakamura T, Ishii K, Matsuura T, Inageda K, Matsumine H, Kido T, Htay L, Kamatani N, Muramatsu M, Kato T. Large-scale search of SNPs for type 2 DM susceptibility genes in a Japanese population. Biochem Biophys Res Commun 2003; 302:751-8. [PMID: 12646233 DOI: 10.1016/s0006-291x(03)00248-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The etiology of type 2 diabetes (DM) is polygenic. We investigated here genes and polymorphisms that associate with DM in the Japanese population. Single-nucleotide polymorphisms (SNPs) of 398 derived from 120 candidate genes were examined for association with DM in a population-based case-control study. The study group consisted of 148 cases and 227 controls recruited from Funagata, Japan. No evident subpopulation structure was detected for the tested population. The association tests were conducted with standard allele positivity tables (chi(2) tests) between SNP genotype frequency and case-control status. The independent association of the SNPs from serum triglyceride levels and body mass index was examined by multiple logistic regression analysis. A value of P<0.01 was accepted as statistically significant. Six genes (met proto-oncogene, ATP-binding cassette transporter A1, fatty acid binding protein 2, LDL receptor defect C complementing, aldolase B, and sulfonylurea receptor) were shown to be associated with DM.
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Affiliation(s)
- Makoto Daimon
- The Third Department of Internal Medicine, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan.
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Abstract
Energy balance in animals is a metabolic state that exists when total body energy expenditure equals dietary energy intake. Energy expenditure, or thermogenesis, can be subcategorized into groups of obligatory and facultative metabolic processes. Brown adipose tissue (BAT), through the activity of uncoupling protein 1 (UCP1), is responsible for nonshivering thermogenesis, a major component of facultative thermogenesis in newborn humans and in small mammals. UCP1, found in the mitochondrial inner membrane in BAT, uncouples energy substrate oxidation from mitochondrial ATP production and hence results in the loss of potential energy as heat. Mice that do not express UCP1 (UCP1 knockouts) are markedly cold sensitive. The recent identification of four new homologs to UCP1 expressed in BAT, muscle, white adipose tissue, brain, and other tissues has been met by tremendous scientific interest. The hypothesis that the novel UCPs may regulate thermogenesis and/or fatty acid metabolism guides investigations worldwide. Despite several hundred publications on the new UCPs, there are a number of significant controversies, and only a limited understanding of their physiological and biochemical properties has emerged. The discovery of UCP orthologs in fish, birds, insects, and even plants suggests the widespread importance of their metabolic functions. Answers to fundamental questions regarding the metabolic functions of the new UCPs are thus pending and more research is needed to elucidate their physiological functions. In this review, we discuss recent findings from mammalian studies in an effort to identify potential patterns of function for the UCPs.
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