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Huang M, Prasad RB, Coral DE, Hjort L, Minja DT, Mulder H, Franks PW, Kalamajski S. Human Genetic Variation at rs10071329 Correlates With Adiposity-Related Traits, Modulates PPARGC1B Expression, and Alters Brown Adipocyte Function. Diabetes 2024; 73:637-645. [PMID: 38190589 PMCID: PMC10958585 DOI: 10.2337/db23-0531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 12/18/2023] [Indexed: 01/10/2024]
Abstract
Human genetic variation in PPARGC1B has been associated with adiposity, but the genetic variants that affect PPARGC1B expression have not been experimentally determined. Here, guided by previous observational data, we used clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) to scarlessly edit the alleles of the candidate causal genetic variant rs10071329 in a human brown adipocyte cell line. Switching the rs10071329 genotype from A/A to G/G enhanced PPARGC1B expression throughout the adipogenic differentiation, identifying rs10071329 as a cis-expression quantitative trait loci (eQTL). The higher PPARGC1B expression in G/G cells coincided with greater accumulation of triglycerides and higher expression of mitochondria-encoded genes, but without significant effects on adipogenic marker expression. Furthermore, G/G cells had improved basal- and norepinephrine-stimulated mitochondrial respiration, possibly relating to enhanced mitochondrial gene expression. The G/G cells also exhibited increased norepinephrine-stimulated glycerol release, indicating improved lipolysis. Altogether, our results showed that rs10071329 is a cis-eQTL, with the G/G genotype conferring enhanced PPARGC1B expression, with consequent improved mitochondrial function and response to norepinephrine in brown adipocytes. This genetic variant, and as yet undetermined eQTLs, at PPARGC1B could prove useful in genotype-based precision medicine for obesity treatment. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Mi Huang
- Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Malmö, Sweden
| | - Rashmi B. Prasad
- Genomics, Diabetes and Endocrinology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Malmö, Sweden
- Institute for Molecular Medicine, Helsinki University, Helsinki, Finland
| | - Daniel E. Coral
- Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Malmö, Sweden
| | - Line Hjort
- Department of Obstetrics, Center for Pregnant Women with Diabetes, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Metabolic Epigenetics Group, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel T.R. Minja
- National Institute for Medical Research, Tanga Center, Tanga, Tanzania
| | - Hindrik Mulder
- Unit of Molecular Metabolism, Department of Clinical Sciences, Clinical Research Centre, Lund University, Malmö, Sweden
| | - Paul W. Franks
- Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Malmö, Sweden
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA
| | - Sebastian Kalamajski
- Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Malmö, Sweden
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Zhang Y, Bowen TR, Lietman SA, Suk M, Williams MS, Lee MTM. PPARGC1B Is Associated with Nontraumatic Osteonecrosis of the Femoral Head: A Genomewide Association Study on a Chart-Reviewed Cohort. J Bone Joint Surg Am 2020; 102:1628-1636. [PMID: 32701715 DOI: 10.2106/jbjs.19.01335] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Previous studies have demonstrated the influence of heritable factors on the development of nontraumatic osteonecrosis of the femoral head (ONFH). We hypothesized that genetic variation is associated with an increased risk of ONFH, and that variants could be identified by a genomewide association study (GWAS). METHODS Using data collected from the MyCode Community Health Initiative, we identified 118 adult patients with radiographically confirmed nontraumatic ONFH. Study patients were statistically compared with a control population of 56,811 unrelated individuals without a diagnosis of ONFH. A case-control GWAS was performed to identify single nucleotide variants (SNVs) associated with ONFH. Sensitivity analyses were performed to evaluate the association of the top SNVs with (cortico)steroid-associated ONFH and ONFH with femoral head collapse. Gene-based analyses were performed to identify potential causal genes. RESULTS Of the 118 patients, 114 (96.6%) had bilateral ONFH at a median of 5 years of follow-up; 90.7% had at least one 3-week steroid prescription compared with 68.3% in controls. A GWAS identified 4 SNVs reaching genomewide significance. rs116468452 near CACNA1E was significantly associated with ONFH (p = 3.26 × 10, odds ratio [OR] = 5.6, 95% confidence interval [CI] = 3.21 to 9.76). rs10953090 in SAMD9 was significantly associated with ONFH in the steroid-exposed subset (p = 2.96 × 10, OR = 2.57, 95% CI = 1.84 to 3.58). rs112467115 in PI4K1B showed enhanced association in the collapsed subset (p = 7.82 × 10, OR = 4.5, 95% CI = 2.60 to 7.79). Gene-based analyses identified PPARGC1B as the only gene significantly associated with ONFH after Bonferroni correction (p = 1 × 10), with the lead SNV being rs78814834 (OR = 2.86, 95% CI = 1.87 to 4.38). CONCLUSIONS We identified 4 SNVs and 1 gene, PPARGC1B, associated with ONFH. LEVEL OF EVIDENCE Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Yanfei Zhang
- Genomic Medicine Institute, Geisinger, Danville, Pennsylvania.,Musculoskeletal Institute, Geisinger, Danville, Pennsylvania
| | - Thomas R Bowen
- Musculoskeletal Institute, Geisinger, Danville, Pennsylvania
| | | | - Michael Suk
- Musculoskeletal Institute, Geisinger, Danville, Pennsylvania
| | - Marc S Williams
- Genomic Medicine Institute, Geisinger, Danville, Pennsylvania
| | - Ming Ta Michael Lee
- Genomic Medicine Institute, Geisinger, Danville, Pennsylvania.,Musculoskeletal Institute, Geisinger, Danville, Pennsylvania
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Kanders SH, Pisanu C, Bandstein M, Jonsson J, Castelao E, Pistis G, Gholam-Rezaee M, Eap CB, Preisig M, Schiöth HB, Mwinyi J. A pharmacogenetic risk score for the evaluation of major depression severity under treatment with antidepressants. Drug Dev Res 2019; 81:102-113. [PMID: 31617956 PMCID: PMC7028038 DOI: 10.1002/ddr.21609] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 09/23/2019] [Accepted: 09/25/2019] [Indexed: 12/28/2022]
Abstract
The severity of symptoms as well as efficacy of antidepressants in major depressive disorder (MDD) is modified by single nucleotide polymorphisms (SNPs) in different genes, which may contribute in an additive or synergistic fashion. We aimed to investigate depression severity in participants with MDD under treatment with antidepressants in relation to the combinatory effect of selected genetic variants combined using a genetic risk score (GRS). The sample included 150 MDD patients on regular AD therapy from the population‐based Swiss PsyCoLaus cohort. We investigated 44 SNPs previously associated with antidepressant response by ranking them with regard to their association to the Center for Epidemiologic Studies Short Depression Scale (CES‐D) score using random forest. The three top scoring SNPs (rs12248560, rs878567, rs17710780) were subsequently combined into an unweighted GRS, which was included in linear and logistic regression models using the CES‐D score, occurrence of a major depressive episode (MDE) during follow‐up and regular antidepressant treatment during the 6 months preceding follow‐up assessment as outcomes. The GRS was associated with MDE occurrence (p = .02) and ln CES‐D score (p = .001). The HTR1A rs878567 variant was associated with ln CES‐D after adjustment for demographic and clinical variables [p = .02, lower scores for minor allele (G) carriers]. Additionally, rs12248560 (CYP2C19) CC homozygotes showed a six‐fold higher likelihood of regular AD therapy at follow‐up compared to minor allele homozygotes [TT; ultrarapid metabolizers (p = .03)]. Our study suggests that the cumulative consideration of pharmacogenetic risk variants more reliably reflects the impact of the genetic background on depression severity than individual SNPs.
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Affiliation(s)
- Sofia H Kanders
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Claudia Pisanu
- Department of Neuroscience, Uppsala University, Uppsala, Sweden.,Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | | | - Jörgen Jonsson
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Enrique Castelao
- Department of Psychiatry, University of Lausanne, Lausanne, Switzerland
| | - Giorgio Pistis
- Department of Psychiatry, University of Lausanne, Lausanne, Switzerland
| | | | - Chin B Eap
- Department of Psychiatry, University of Lausanne, Lausanne, Switzerland.,Department of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Switzerland
| | - Martin Preisig
- Department of Psychiatry, University of Lausanne, Lausanne, Switzerland
| | - Helgi B Schiöth
- Department of Neuroscience, Uppsala University, Uppsala, Sweden.,Institute for Translational Medicine and Biotechnology, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Jessica Mwinyi
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
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Cao J, Wang X, Wang D, Ma R, Li X, Feng H, Wang J, Liu S, Wang L. PGC-1β cooperating with FOXA2 inhibits proliferation and migration of breast cancer cells. Cancer Cell Int 2019; 19:93. [PMID: 31007610 PMCID: PMC6458718 DOI: 10.1186/s12935-019-0810-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/29/2019] [Indexed: 11/24/2022] Open
Abstract
Background Breast cancer is one of the most common malignancy among females from the worldwide cancer incidence statistics. Peroxisome gamma coactivator-1β (PGC-1β) has long been identified to be involved in this type of tumorigenesis. However, the mechanisms of PGC-1β in human breast cancer have not been fully understood and the function requires to be further elucidated. Methods mRNA and protein expression of PGC-1β and FOXA2 in breast cancer tissues and cell lines were determined by qRT-PCR and Western Blotting, respectively. To further visualize the expression and localization of PGC-1β and FOXA2, immunochemistry and immunofluorescence staining methods were employed. The effect of PGC-1β and FOXA2 on cell proliferation and migration were evaluated by CCK8, clone formation, transwell and wound-healing assays, which has been done either with stable PGC-1β knockdown or FOXA2 overexpression in vitro. Xenografts model of nude mice were used to evaluate tumor growth in vivo. In addition, proteins expression of the PI3K-AKT-mTOR signaling pathway involved in the regulation of breast cancer were detected by Western Blotting. Results Our results showed that PGC-1β was upregulated and FOXA2 was downregulated in breast cancer tissues and cell lines. These two proteins can be interacted with each other to form the complex. Also, we found the combination of PGC-1β interference with FOXA2 overexpression significantly inhibited cell proliferation and migration in vitro as well as tumor growth in vivo. We further identified that PGC-1β and FOXA2 strongly correlated with the PI3K-AKT-mTOR signaling pathway, and they exerted their biological functions by activating this pathway. Conclusions We demonstrated that downregulation of PGC-1β combined with overexpression of FOXA2 obviously inhibited the function of breast cancer cells through regulating the PI3K-AKT-mTOR pathway.
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Affiliation(s)
- Jia Cao
- 1School of Clinical Medicine, Ningxia Medical University, Yinchuan, 750004 China.,2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Xi Wang
- 1School of Clinical Medicine, Ningxia Medical University, Yinchuan, 750004 China.,2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Danni Wang
- 1School of Clinical Medicine, Ningxia Medical University, Yinchuan, 750004 China.,2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Rong Ma
- 2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Xiaohan Li
- 1School of Clinical Medicine, Ningxia Medical University, Yinchuan, 750004 China.,2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Huimin Feng
- 1School of Clinical Medicine, Ningxia Medical University, Yinchuan, 750004 China.,2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Jia Wang
- 2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
| | - Shihai Liu
- 3Medical Animal Lab, The Affiliated Hospital of Qingdao University, Qingdao, 266003 China
| | - Libin Wang
- 1School of Clinical Medicine, Ningxia Medical University, Yinchuan, 750004 China.,2Beijing National Biochip Research Center Sub-Center in Ningxia, The General Hospital of Ningxia Medical University, Yinchuan, 750004 China
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5
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Liu LL, Liu L, Liu HH, Ren SS, Dou CY, Cheng PP, Wang CL, Wang LN, Chen XL, Zhang H, Chen MT. Levamisole suppresses adipogenesis of aplastic anaemia-derived bone marrow mesenchymal stem cells through ZFP36L1-PPARGC1B axis. J Cell Mol Med 2018; 22:4496-4506. [PMID: 29993187 PMCID: PMC6111807 DOI: 10.1111/jcmm.13761] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/08/2018] [Indexed: 11/26/2022] Open
Abstract
Aplastic anaemia (AA) is a life‐threatening hematopoietic disorder characterized by hypoplasia and pancytopenia with increasing fat cells in the bone marrow (BM). The BM‐derived mesenchymal stem cells (MSCs) from AA are more susceptible to be induced into adipogenic differentiation compared with that from control, which may be causatively associated with the fatty BM and defective hematopoiesis of AA. Here in this study, we first demonstrated that levamisole displayed a significant suppressive effect on the in vitro adipogenic differentiation of AA BM‐MSCs. Mechanistic investigation revealed that levamisole could increase the expression of ZFP36L1 which was subsequently demonstrated to function as a negative regulator of adipogenic differentiation of AA BM‐MSCs through lentivirus‐mediated ZFP36L1 knock‐down and overexpression assay. Peroxisome proliferator‐activated receptor gamma coactivator 1 beta (PPARGC1B) whose 3′‐untranslated region bears adenine‐uridine‐rich elements was verified as a direct downstream target of ZFP36L1, and knock‐down of PPARGC1B impaired the adipogenesis of AA BM‐MSCs. Collectively, our work demonstrated that ZFP36L1‐mediated post‐transcriptional control of PPARGC1B expression underlies the suppressive effect of levamisole on the adipogenic differentiation of AA BM‐MSCs, which not only provides novel therapeutic targets for alleviating the BM fatty phenomenon of AA patients, but also lays the theoretical and experimental foundation for the clinical application of levamisole in AA therapy.
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Affiliation(s)
- Lu-Lu Liu
- Central Laboratory, Affiliated Hospital of Jining Medical University, Jining, China
| | - Lei Liu
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Hai-Hui Liu
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China.,Department of Graduate School, Jining Medical University, Jining, China
| | - Sai-Sai Ren
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Cui-Yun Dou
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Pan-Pan Cheng
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Cui-Ling Wang
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Li-Na Wang
- Central Laboratory, Affiliated Hospital of Jining Medical University, Jining, China
| | - Xiao-Li Chen
- Department of Graduate School, Jining Medical University, Jining, China
| | - Hao Zhang
- Department of Hematology, Affiliated Hospital of Jining Medical University, Jining, China
| | - Ming-Tai Chen
- Central Laboratory, Affiliated Hospital of Jining Medical University, Jining, China
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Zhu L, Huang Q, Xie Z, Kang M, Ding H, Chen B, Chen Y, Liu C, Wang Y, Tang W. PPARGC1A rs3736265 G>A polymorphism is associated with decreased risk of type 2 diabetes mellitus and fasting plasma glucose level. Oncotarget 2018; 8:37308-37320. [PMID: 28418876 PMCID: PMC5514910 DOI: 10.18632/oncotarget.16307] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 02/13/2017] [Indexed: 12/21/2022] Open
Abstract
It has been reported that peroxisome proliferator-activated receptor gamma (PPARG) and peroxisome proliferator-activated receptor gamma co-activator 1 (PPARGC1) family (e.g. PPARGC1A and PPARGC1B) are key agents in the development and pathophysiology of type 2 diabetes mellitus (T2DM). In this study, we designed a case-control study and selected PPARG rs1801282 C>G, PPARG rs3856806 C>T, PPARGC1A rs8192678 C>T, PPARGC1A rs2970847 C>T, PPARGC1A rs3736265 G>A, PPARGC1B rs7732671 G>C and PPARGC1B rs17572019 G>A polymorphisms to assess the relationship between these polymorphisms and T2DM using the SNPscan method. A total of 502 T2DM patients and 784 non-diabetic controls were enrolled. We found that PPARGC1A rs3736265 G>A polymorphism was correlated with a borderline decreased susceptibility of T2DM. In a subgroup analysis by age, sex, alcohol use, smoking status and body mass index, a significantly decreased risk of T2DM in <65 years and female groups was found. Haplotype comparison analysis indicated that CTTCGGG and CTCTGGG haplotypes with the order of PPARG rs1801282 C>G, PPARG rs3856806 C>T, PPARGC1A rs8192678 C>T, PPARGC1A rs2970847 C>T, PPARGC1A rs3736265 G>A, PPARGC1B rs7732671 G>C and PPARGC1B rs17572019 G>A polymorphisms in gene position significantly increased the risk of T2DM. However, CCCCACA haplotype conferred a decreased risk to T2DM. We also found that PPARGC1A rs3736265 A allele decreased the level of fasting plasma glucose (FPG), while increased the level of Triglyceride. In conclusion, Our findings suggest that variants of PPARGC1A rs3736265 G>A polymorphism decrease the level of FPG, improving the expectation of study in individual's prevention strategies to T2DM.
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Affiliation(s)
- Li Zhu
- Department of Nephrology, Affiliated People's Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Qiuyu Huang
- Department of Cardiac Surgery, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China
| | - Zhiqiang Xie
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China
| | - Mingqiang Kang
- Department of Thoracic Surgery, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China
| | - Hao Ding
- Department of Respiratory Disease, Affiliated People's Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Boyang Chen
- Department of Thoracic Surgery, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China
| | - Yu Chen
- Department of Medical Oncology, Fujian Provincial Cancer Hospital, Fujian Medical University Cancer Hospital, Fuzhou, Fujian Province, China
| | - Chao Liu
- Department of Cardiothoracic Surgery, Affiliated People's Hospital of Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Yafeng Wang
- Department of Cardiology, The People's Hospital of Xishuangbanna Dai Autonomous Prefecture, Jinghong, Yunnan Province, China
| | - Weifeng Tang
- Department of Thoracic Surgery, Fujian Medical University Union Hospital, Fuzhou, Fujian Province, China
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Chang WC, Jan Wu YJ, Chung WH, Lee YS, Chin SW, Chen TJ, Chang YS, Chen DY, Hung SI. Genetic variants of PPAR-gamma coactivator 1B augment NLRP3-mediated inflammation in gouty arthritis. Rheumatology (Oxford) 2017; 56:457-466. [PMID: 28394398 DOI: 10.1093/rheumatology/kew337] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Indexed: 12/22/2022] Open
Abstract
Objective Gout is characterized by recurrent attacks of arthritis with hyperuricaemia and urate crystal-induced inflammation. Although urate transporters are known as risk factors, the immunogenetics of gouty inflammation remains unclear. This study aimed to investigate the genetic association between immune/metabolism regulators and gout. Methods We enrolled 448 gout patients and 943 population controls from Taiwan; all were Han Chinese. We screened association between gout and 22 variants of candidate genes, including NLRP3 , caspase 1, peroxisome proliferator-activated receptor-γ, proliferator-activated receptor-γ coactivator 1α ( PPARGC1A ) and 1β ( PPARGC1B ). The association was validated by replication and combined-sample analyses. Functional assays were performed by quantitative PCR, ELISA, siRNA knockdown and transfection using THP-1 cells, peripheral blood mononuclear cells and synovial cells from patients. Results Gouty arthritis exhibited significant association with variants of peroxisome PPARGC1B , which included a missense single nucleotide polymorphism, rs45520937 [P = 6.66 × 10 -9 ; odds ratio (95% CI): 1.85 (1.51, 2.28)]. Expression of PPARGC1B and NLRP3 was induced in urate crystal-activated THP-1, peripheral blood mononuclear cells and synovial cells from gout patients in acute stage. siRNA knockdown of PPARGC1B upregulated NLRP3 in urate crystal-activated macrophages. Compared with the wild-type carriers, patients with the risk A allele of rs45520937 showed statistically increased NLRP3 (P = 0.044) and plasma IL-1β (P = 0.006). Transfection of PPARGC1B cDNA with rs45520937 A allele to macrophages significantly augmented the expression of NLRP3 and IL-1β. Conclusion Genetic variants of PPARGC1B are significantly associated with gout, and a missense single nucleotide polymorphism, rs45520937, augments NLRP3 and IL-1β expression. These data suggest that variants of PPARGC1B , a regulator of metabolism and inflammation, contribute to the pathogenesis of gouty arthritis.
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Affiliation(s)
- Wan-Chun Chang
- Institute of Pharmacology, Program in Molecular Medicine, School of Medicine, National Yang-Ming University, Taipei
| | - Yeong-Jian Jan Wu
- Department of Medicine, Division of Allergy, Immunology and Rheumatology, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Keelung
| | - Wen-Hung Chung
- Department of Dermatology, Drug Hypersensitivity Clinical and Research Center, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Taipei
| | - Yun-Shien Lee
- Department of Biotechnology, Ming Chuan University, Taoyuan
| | - See-Wen Chin
- Institute of Pharmacology, Program in Molecular Medicine, School of Medicine, National Yang-Ming University, Taipei.,Department of Dermatology, Drug Hypersensitivity Clinical and Research Center, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Taipei
| | - Ting-Jui Chen
- Institute of Pharmacology, Program in Molecular Medicine, School of Medicine, National Yang-Ming University, Taipei.,Department of Dermatology, Wan Fang Hospital, Taipei Medical University, Taipei
| | - Yu-Sun Chang
- Institute of Biomedical Sciences, Molecular Medicine Research Center, School of Medicine, Chang Gung University, Taoyuan
| | - Der-Yuan Chen
- Department of Rheumatology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Shuen-Iu Hung
- Institute of Pharmacology, Program in Molecular Medicine, School of Medicine, National Yang-Ming University, Taipei
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Oelsner KT, Guo Y, To SBC, Non AL, Barkin SL. Maternal BMI as a predictor of methylation of obesity-related genes in saliva samples from preschool-age Hispanic children at-risk for obesity. BMC Genomics 2017; 18:57. [PMID: 28068899 PMCID: PMC5223358 DOI: 10.1186/s12864-016-3473-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 12/26/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The study of epigenetic processes and mechanisms present a dynamic approach to assess complex individual variation in obesity susceptibility. However, few studies have examined epigenetic patterns in preschool-age children at-risk for obesity despite the relevance of this developmental stage to trajectories of weight gain. We hypothesized that salivary DNA methylation patterns of key obesogenic genes in Hispanic children would 1) correlate with maternal BMI and 2) allow for identification of pathways associated with children at-risk for obesity. RESULTS Genome-wide DNA methylation was conducted on 92 saliva samples collected from Hispanic preschool children using the Infinium Illumina HumanMethylation 450 K BeadChip (Illumina, San Diego, CA, USA), which interrogates >484,000 CpG sites associated with ~24,000 genes. The analysis was limited to 936 genes that have been associated with obesity in a prior GWAS Study. Child DNA methylation at 17 CpG sites was found to be significantly associated with maternal BMI, with increased methylation at 12 CpG sites and decreased methylation at 5 CpG sites. Pathway analysis revealed methylation at these sites related to homocysteine and methionine degradation as well as cysteine biosynthesis and circadian rhythm. Furthermore, eight of the 17 CpG sites reside in genes (FSTL1, SORCS2, NRF1, DLC1, PPARGC1B, CHN2, NXPH1) that have prior known associations with obesity, diabetes, and the insulin pathway. CONCLUSIONS Our study confirms that saliva is a practical human tissue to obtain in community settings and in pediatric populations. These salivary findings indicate potential epigenetic differences in Hispanic preschool children at risk for pediatric obesity. Identifying early biomarkers and understanding pathways that are epigenetically regulated during this critical stage of child development may present an opportunity for prevention or early intervention for addressing childhood obesity. TRIAL REGISTRATION The clinical trial protocol is available at ClinicalTrials.gov ( NCT01316653 ). Registered 3 March 2011.
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Affiliation(s)
- Kathryn Tully Oelsner
- College of Medicine, Medical University of South Carolina, 96 Jonathan Lucas St, Suite 601, MSC 617, Charleston, SC 29425 USA
| | - Yan Guo
- Center for Quantitative Research, School of Medicine, Vanderbilt University, 2220 Pierce Ave, 571 Preston Research Building, Nashville, TN USA
| | - Sophie Bao-Chieu To
- Department of Biological Sciences, Vanderbilt University, 1210 BSB, 465 21st Ave S, Nashville, TN USA
| | - Amy L. Non
- Department of Anthropology, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093 USA
| | - Shari L. Barkin
- Department of Pediatrics, Vanderbilt University School of Medicine, 2200 Children’s Way, Doctor’s Office Tower 8232, Nashville, TN 37232-9225 USA
- Pediatric Obesity Research, Diabetes Research and Training Center, Vanderbilt University School of Medicine, 2200 Children’s Way, Doctor’s Office Tower 8232, Nashville, TN 37232-9225 USA
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9
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Golpich M, Amini E, Mohamed Z, Azman Ali R, Mohamed Ibrahim N, Ahmadiani A. Mitochondrial Dysfunction and Biogenesis in Neurodegenerative diseases: Pathogenesis and Treatment. CNS Neurosci Ther 2017; 23:5-22. [PMID: 27873462 PMCID: PMC6492703 DOI: 10.1111/cns.12655] [Citation(s) in RCA: 353] [Impact Index Per Article: 50.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 09/29/2016] [Accepted: 10/04/2016] [Indexed: 12/11/2022] Open
Abstract
Neurodegenerative diseases are a heterogeneous group of disorders that are incurable and characterized by the progressive degeneration of the function and structure of the central nervous system (CNS) for reasons that are not yet understood. Neurodegeneration is the umbrella term for the progressive death of nerve cells and loss of brain tissue. Because of their high energy requirements, neurons are especially vulnerable to injury and death from dysfunctional mitochondria. Widespread damage to mitochondria causes cells to die because they can no longer produce enough energy. Several lines of pathological and physiological evidence reveal that impaired mitochondrial function and dynamics play crucial roles in aging and pathogenesis of neurodegenerative diseases. As mitochondria are the major intracellular organelles that regulate both cell survival and death, they are highly considered as a potential target for pharmacological-based therapies. The purpose of this review was to present the current status of our knowledge and understanding of the involvement of mitochondrial dysfunction in pathogenesis of neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) and the importance of mitochondrial biogenesis as a potential novel therapeutic target for their treatment. Likewise, we highlight a concise overview of the key roles of mitochondrial electron transport chain (ETC.) complexes as well as mitochondrial biogenesis regulators regarding those diseases.
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Affiliation(s)
- Mojtaba Golpich
- Department of MedicineUniversiti Kebangsaan Malaysia Medical CentreCherasKuala LumpurMalaysia
| | - Elham Amini
- Department of MedicineUniversiti Kebangsaan Malaysia Medical CentreCherasKuala LumpurMalaysia
| | - Zahurin Mohamed
- Department of PharmacologyFaculty of MedicineUniversity of MalayaKuala LumpurMalaysia
| | - Raymond Azman Ali
- Department of MedicineUniversiti Kebangsaan Malaysia Medical CentreCherasKuala LumpurMalaysia
| | | | - Abolhassan Ahmadiani
- Neuroscience Research CenterShahid Beheshti University of Medical SciencesTehranIran
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10
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Chang HS, Lee SH, Lee JU, Park JS, Chung IY, Park CS. Functional Characterization of Exonic Variants of the PPARGC1B Gene in Coregulation of Estrogen Receptor Alpha. DNA Cell Biol 2016; 35:314-21. [PMID: 27027322 DOI: 10.1089/dna.2015.3195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Peroxisome proliferator-activated receptor gamma coactivator 1 beta (PPARGC1B) is a coactivator of estrogen receptor (ER)α and ERβ. We previously demonstrated a significant association between a variant of exon 5 of the PPARGC1B gene (+102525 G>A, R265Q) and airway hyperreactivity (AHR). The aims of the study were to evaluate the genetic effects of variants of the PPARGC1B gene on the function of ERs. PPARGC1B +102525G and A gene constructs were generated using PCR and cloned into a pCMV4 promoter vector. A luciferase reporter assay was undertaken in 293T cells cotransfected with one of the PPARGC1B +102525G>A constructs, ERα, and an estrogen response element (ERE) containing a luciferase construct after treatment with 17β-estradiol. According to the luciferase reporter assay, the +102525A allele showed higher ERα activity than the +102525G allele in response to stimulation with 17β-estradiol. In addition, the interaction between ERα and PPARGC1B was evaluated by coprecipitation assay. Human influenza hemagglutinin-tagged PPARGC1B coprecipitated more intensely with ERα in the +102525A than the +102525G construct after 17β estradiol treatment. The variant +102525A allele enhances the activity of ERα to a greater degree than the +102525G allele of PPARGC1B.
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Affiliation(s)
- Hun Soo Chang
- 1 Department of Medical Bioscience, Graduate School, Soonchunhyang University , Asan, Republic of Korea
| | - Shin-Hwa Lee
- 1 Department of Medical Bioscience, Graduate School, Soonchunhyang University , Asan, Republic of Korea
| | - Jong-Uk Lee
- 1 Department of Medical Bioscience, Graduate School, Soonchunhyang University , Asan, Republic of Korea
| | - Jong Sook Park
- 2 Division of Allergy and Respiratory Medicine, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital , Bucheon, Republic of Korea
| | - Il Yup Chung
- 3 Division of Molecular and Life Sciences, College of Science and Technology, Hanyang University , Ansan, Republic of Korea
| | - Choon-Sik Park
- 1 Department of Medical Bioscience, Graduate School, Soonchunhyang University , Asan, Republic of Korea.,2 Division of Allergy and Respiratory Medicine, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital , Bucheon, Republic of Korea
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Vilahur N, Bustamante M, Morales E, Motta V, Fernandez MF, Salas LA, Escaramis G, Ballester F, Murcia M, Tardon A, Riaño I, Santa-Marina L, Ibarluzea J, Arrebola JP, Estivill X, Bollati V, Sunyer J, Olea N. Prenatal exposure to mixtures of xenoestrogens and genome-wide DNA methylation in human placenta. Epigenomics 2016; 8:43-54. [DOI: 10.2217/epi.15.91] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Background: In utero exposure to xenostrogens may modify the epigenome. We explored the association of prenatal exposure to mixtures of xenoestrogens and genome-wide placental DNA methylation. Materials & methods: Sex-specific associations between methylation changes in placental DNA by doubling the concentration of TEXB-alpha exposure were evaluated by robust multiple linear regression. Two CpG sites were selected for validation and replication in additional male born placentas. Results: No significant associations were found, although the top significant CpGs in boys were located in the LRPAP1, HAGH, PPARGC1B, KCNQ1 and KCNQ1DN genes, previously associated to birth weight, Type 2 diabetes, obesity or steroid hormone signaling. Neither technical validation nor biological replication of the results was found in boys for LRPAP and PPARGC1B. Conclusion: Some suggestive genes were differentially methylated in boys in relation to prenatal xenoestrogen exposure, but our initial findings could not be validated or replicated.
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Affiliation(s)
- Nadia Vilahur
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Genomics & Disease Group, Bioinformatics & Genomics Program, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Mariona Bustamante
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Genomics & Disease Group, Bioinformatics & Genomics Program, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Eva Morales
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- IMIB-Arrixaca Research Institute, Virgen de la Arrixaca University Hospital, Murcia, Spain
| | - Valeria Motta
- EPIGET – Epidemiology, Epigenetics & Toxicology Lab – Department of Clinical Sciences & Community Health, Università degli Studi di Milano, Milan, Italy
| | - Mariana Fátima Fernandez
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Department of Radiology, University of Granada, Spain
- Instituto de Investigación Biosanitaria, ibs.GRANADA, Spain
| | - Lucas Andrés Salas
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
| | - Georgia Escaramis
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Genomics & Disease Group, Bioinformatics & Genomics Program, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Ferran Ballester
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- FISABIO-Universitat de València – Universitat Jaume I Joint Research Unit of Epidemiology & Environmental Health, Valencia, Spain
- University of Valencia, Valencia, Spain
| | - Mario Murcia
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- FISABIO-Universitat de València – Universitat Jaume I Joint Research Unit of Epidemiology & Environmental Health, Valencia, Spain
| | - Adonina Tardon
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- University of Oviedo, Oviedo, Asturias, Spain
| | - Isolina Riaño
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Hospital San Agustín, SESPA, Asturias, Spain
| | - Loreto Santa-Marina
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Biodonostia, Health Research Institute, San Sebastián, Spain
- Public Health of Gipuzkoa, Department of Health, Government of the Basque Country, San Sebastian, Spain
| | - Jesús Ibarluzea
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Biodonostia, Health Research Institute, San Sebastián, Spain
- Public Health of Gipuzkoa, Department of Health, Government of the Basque Country, San Sebastian, Spain
| | - Juan Pedro Arrebola
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Department of Radiology, University of Granada, Spain
- Instituto de Investigación Biosanitaria, ibs.GRANADA, Spain
| | - Xavier Estivill
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Genomics & Disease Group, Bioinformatics & Genomics Program, Centre for Genomic Regulation (CRG), Barcelona, Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
| | - Valentina Bollati
- EPIGET – Epidemiology, Epigenetics & Toxicology Lab – Department of Clinical Sciences & Community Health, Università degli Studi di Milano, Milan, Italy
| | - Jordi Sunyer
- ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Hospital del Mar Research Institute (IMIM), Barcelona, Spain
| | - Nicolás Olea
- CIBER Epidemiología y Salud Pública (CIBERESP), Spain
- Department of Radiology, University of Granada, Spain
- Instituto de Investigación Biosanitaria, ibs.GRANADA, Spain
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Oropeza D, Jouvet N, Bouyakdan K, Perron G, Ringuette LJ, Philipson LH, Kiss RS, Poitout V, Alquier T, Estall JL. PGC-1 coactivators in β-cells regulate lipid metabolism and are essential for insulin secretion coupled to fatty acids. Mol Metab 2015; 4:811-22. [PMID: 26629405 PMCID: PMC4632114 DOI: 10.1016/j.molmet.2015.08.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 07/30/2015] [Accepted: 08/05/2015] [Indexed: 11/30/2022] Open
Abstract
Objectives Peroxisome proliferator-activated receptor γ coactivator 1 (PPARGCA1, PGC-1) transcriptional coactivators control gene programs important for nutrient metabolism. Islets of type 2 diabetic subjects have reduced PGC-1α expression and this is associated with decreased insulin secretion, yet little is known about why this occurs or what role it plays in the development of diabetes. Our goal was to delineate the role and importance of PGC-1 proteins to β-cell function and energy homeostasis. Methods We investigated how nutrient signals regulate coactivator expression in islets and the metabolic consequences of reduced PGC-1α and PGC-1β in primary and cultured β-cells. Mice with inducible β-cell specific double knockout of Pgc-1α/Pgc-1β (βPgc-1 KO) were created to determine the physiological impact of reduced Pgc1 expression on glucose homeostasis. Results Pgc-1α and Pgc-1β expression was increased in primary mouse and human islets by acute glucose and palmitate exposure. Surprisingly, PGC-1 proteins were dispensable for the maintenance of mitochondrial mass, gene expression, and oxygen consumption in response to glucose in adult β-cells. However, islets and mice with an inducible, β-cell-specific PGC-1 knockout had decreased insulin secretion due in large part to loss of the potentiating effect of fatty acids. Consistent with an essential role for PGC-1 in lipid metabolism, β-cells with reduced PGC-1s accumulated acyl-glycerols and PGC-1s controlled expression of key enzymes in lipolysis and the glycerolipid/free fatty acid cycle. Conclusions These data highlight the importance of PGC-1s in coupling β-cell lipid metabolism to promote efficient insulin secretion. Loss of Pgc-1s in adult β-cells decreases insulin secretion in response to glucose/palmitate. Pgc-1α/β is not required to maintain basal mitochondrial mass or oxidative capacity in mature β-cells. Pgc-1α/β regulates expression of the lipolytic enzymes HSL and ATGL in β-cells. Reduced β-cell Pgc-1 causes accumulation of intracellular acyl-glycerols and cholesterol esters.
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Affiliation(s)
- Daniel Oropeza
- Laboratory of Molecular Mechanisms of Diabetes, Institut de Recherches Cliniques de Montreal (IRCM), 110 Ave des Pins Ouest, Montreal, Quebec, H2W 1R7, Canada ; Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada
| | - Nathalie Jouvet
- Laboratory of Molecular Mechanisms of Diabetes, Institut de Recherches Cliniques de Montreal (IRCM), 110 Ave des Pins Ouest, Montreal, Quebec, H2W 1R7, Canada ; Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Khalil Bouyakdan
- Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
| | - Gabrielle Perron
- Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada
| | - Lea-Jeanne Ringuette
- Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada
| | - Louis H Philipson
- Department of Medicine, University of Chicago, 5801 South Ellis Avenue, Chicago, IL, USA
| | - Robert S Kiss
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Vincent Poitout
- Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
| | - Thierry Alquier
- Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
| | - Jennifer L Estall
- Laboratory of Molecular Mechanisms of Diabetes, Institut de Recherches Cliniques de Montreal (IRCM), 110 Ave des Pins Ouest, Montreal, Quebec, H2W 1R7, Canada ; Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada ; Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
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Fam BC, Sgambellone R, Ruan Z, Proietto J, Andrikopoulos S. Contribution of the hypothalamus and gut to weight gain susceptibility and resistance in mice. J Endocrinol 2015; 225:191-204. [PMID: 25934705 DOI: 10.1530/joe-15-0131] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/30/2015] [Indexed: 12/15/2022]
Abstract
Obesity susceptibility in humans and in rodent strains varies in response to the consumption of high-energy density (HED) diets. However, the exact mechanism(s) involved in this susceptibility remain(s) unresolved. The aim of the present study was to gain greater insight into this susceptibility by using C57BL/6J (B6) mice that were separated into obesity-prone (diet-induced obese (DIO)) and obesity-resistant (diet-induced resistant (DR)) groups following an HED diet for 6 weeks. Physiological, biochemical and gene expression assessments of energy balance were performed in the DIO and DR mice on an HED diet and chow-fed mice. The increased weight gain of the DIO mice as compared to the DR mice was associated with increased energy intake and higher plasma leptin and adiponectin levels but not with reduced physical activity or resting energy expenditure. Hypothalamic Pomc gene expression was elevated, but there were no changes in Npy or Agrp expression. Adipose tissue leptin and adiponectin gene expression were significantly reduced in the DIO group as compared to the DR group. Interestingly, ileum expression of G protein-coupled receptor (Gpr) 40 (Gpr40) was significantly increased, whereas Gpr120, Gpr119, Gpr41, and glucagon-like peptide 1 (Glp1) were reduced. Contrastingly, the lower weight gain of the DR group was associated with elevated adipose tissue leptin and adiponectin gene expression, but there were no differences in plasma hormone or hypothalamic gene expression levels as compared to chow-fed mice. Therefore, the present data demonstrate that susceptibility and resistance to diet-induced weight gain in B6 mice appears to be predominantly driven by peripheral rather than hypothalamic modifications, and changes in gut-specific receptors are a potentially important contributor to this variation.
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Affiliation(s)
- Barbara C Fam
- Department of Medicine (Austin Health) Austin Hospital, The University of Melbourne, Level 7, Lance Townsend Building, Studley Road, Heidelberg, Victoria 3084, Australia
| | - Rebecca Sgambellone
- Department of Medicine (Austin Health) Austin Hospital, The University of Melbourne, Level 7, Lance Townsend Building, Studley Road, Heidelberg, Victoria 3084, Australia
| | - Zheng Ruan
- Department of Medicine (Austin Health) Austin Hospital, The University of Melbourne, Level 7, Lance Townsend Building, Studley Road, Heidelberg, Victoria 3084, Australia
| | - Joseph Proietto
- Department of Medicine (Austin Health) Austin Hospital, The University of Melbourne, Level 7, Lance Townsend Building, Studley Road, Heidelberg, Victoria 3084, Australia
| | - Sofianos Andrikopoulos
- Department of Medicine (Austin Health) Austin Hospital, The University of Melbourne, Level 7, Lance Townsend Building, Studley Road, Heidelberg, Victoria 3084, Australia
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Kripke DF, Kline LE, Nievergelt CM, Murray SS, Shadan FF, Dawson A, Poceta JS, Cronin J, Jamil SM, Tranah GJ, Loving RT, Grizas AP, Hahn EK. Genetic variants associated with sleep disorders. Sleep Med 2015; 16:217-24. [PMID: 25660813 PMCID: PMC4352103 DOI: 10.1016/j.sleep.2014.11.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 10/30/2014] [Accepted: 11/14/2014] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The diagnostic boundaries of sleep disorders are under considerable debate. The main sleep disorders are partly heritable; therefore, defining heritable pathophysiologic mechanisms could delineate diagnoses and suggest treatment. We collected clinical data and DNA from consenting patients scheduled to undergo clinical polysomnograms, to expand our understanding of the polymorphisms associated with the phenotypes of particular sleep disorders. METHODS Patients at least 21 years of age were recruited to contribute research questionnaires, and to provide access to their medical records, saliva for deoxyribonucleic acid (DNA), and polysomnographic data. From these complex data, 38 partly overlapping phenotypes were derived indicating complaints, subjective and objective sleep timing, and polysomnographic disturbances. A custom chip was used to genotype 768 single-nucleotide polymorphisms (SNPs). Additional assays derived ancestry-informative markers (eg, 751 participants of European ancestry). Linear regressions controlling for age, gender, and ancestry were used to assess the associations of each phenotype with each of the SNPs, highlighting those with Bonferroni-corrected significance. RESULTS In peroxisome proliferator-activated receptor gamma, coactivator 1 beta (PPARGC1B), rs6888451 was associated with several markers of obstructive sleep apnea. In aryl hydrocarbon receptor nuclear translocator-like (ARNTL), rs10766071 was associated with decreased polysomnographic sleep duration. The association of rs3923809 in BTBD9 with periodic limb movements in sleep was confirmed. SNPs in casein kinase 1 delta (CSNK1D rs11552085), cryptochrome 1 (CRY1 rs4964515), and retinoic acid receptor-related orphan receptor A (RORA rs11071547) were less persuasively associated with sleep latency and time of falling asleep. CONCLUSIONS SNPs associated with several sleep phenotypes were suggested, but due to risks of false discovery, independent replications are needed before the importance of these associations can be assessed, followed by investigation of molecular mechanisms.
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Affiliation(s)
- Daniel F Kripke
- Viterbi Family Sleep Center, Scripps Clinic, La Jolla, CA, USA; Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA.
| | | | | | - Sarah S Murray
- Department of Pathology, Center for Advanced Laboratory Medicine, University of California, San Diego, CA, USA
| | - Farhad F Shadan
- Viterbi Family Sleep Center, Scripps Clinic, La Jolla, CA, USA
| | - Arthur Dawson
- Viterbi Family Sleep Center, Scripps Clinic, La Jolla, CA, USA
| | - J Steven Poceta
- Viterbi Family Sleep Center, Scripps Clinic, La Jolla, CA, USA
| | - John Cronin
- Viterbi Family Sleep Center, Scripps Clinic, La Jolla, CA, USA
| | - Shazia M Jamil
- Viterbi Family Sleep Center, Scripps Clinic, La Jolla, CA, USA
| | - Gregory J Tranah
- California Pacific Medical Center Research Institute, San Francisco, CA, USA
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Zhai N, Sun C, Gu W, He X, Shan A, Sun H, Lu N, Cui B, Ning G. Resistance to high-fat diet-induced obesity in male heterozygous Pprc1 knockout mice. Endocr J 2015; 62:633-44. [PMID: 25994039 DOI: 10.1507/endocrj.ej14-0383] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Peroxisome proliferator-activated receptor gamma, co-activator-related 1 (Pprc1) is the third member of the Pgc1 family. Other than the well-characterized Pgc1a and Pgc1b that act as regulators of mitochondrial biogenesis and oxidative metabolism, the function of Pprc1 in vivo is rarely reported, due to embryonic lethality of whole-body Pprc1 knockout mice. To investigate the biological and physiological function of Pprc1 in metabolic processes, male Pprc1(+/-) mice fed with a high fat diet (HFD) showed resistance to diet-induced obesity with a decrease of adipose tissue in Pprc1(+/-) mice, which was a result of elevated energy expenditure. In skeletal muscle of Pprc1(+/-) mice, Pprc1 level showed haplo-insufficiency with down-regulation of Pgc1b and Pgc1a, whereas in adipose tissue, Pprc1 expression remained normal, with significant compensatory increase of other Pgc1 family members to induce an up-regulation of respiratory chain genes. Taken together, as the first report on the metabolic roles of Pprc1 in vivo, these results indicated an elevated basal metabolic rate and lipid metabolic alteration of male Pprc1(+/-) mice on HFD, suggesting the significant role of Pprc1 in controlling mitochondrial gene expression and energy metabolic processes, synergistically with Pgc1a and Pgc1b.
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Affiliation(s)
- Nan Zhai
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrinology and Metabolism, Endocrine and Metabolic E-Institutes of Shanghai Universities and Key Laboratory for Endocrinology and Metabolism of Chinese Health Ministry, Rui-jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shang Hai 200025, China
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Moon KY, Park MK, Leikauf GD, Park CS, Jang AS. Diesel exhaust particle-induced airway responses are augmented in obese rats. Int J Toxicol 2014; 33:21-8. [PMID: 24536021 DOI: 10.1177/1091581813518355] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Air pollutants and obesity are important factors that contribute to asthma. The aim of this study was to assess the airway responsiveness and inflammation in Otsuka-Long Evans Tokushima Fatty (OLETF) obese rats and Long Evans Tokushima-Otsuka (LETO) nonobese rats exposed to diesel exhaust particles (DEPs). Otsuka Long Evans Tokushima fatty rats and LETO rats were exposed intranasally to DEP and then challenged with aerosolized DEP on days 6 to 8. Body plethysmography, bronchoalveolar lavage (BAL), and histology were performed. Enhanced pause (Penh) was measured as an indicator of airway resistance on day 9 and samples were collected on day 10. After exposure to DEP, the OLETF group exhibited a greater increase in Penh compared to that in the LETO group. Moreover, the BAL fluid in mice showed an increase in the total and differential cell counts in the DEP-exposed OLETF group compared to that in the DEP-exposed LETO group. Histological assessment of lung tissue from each group revealed that the DEP-exposed OLETF group tended to have increased inflammatory cell infiltrations in the prebronchial area. Increased peroxisome proliferator-activated receptor γ, coactivator 1β messenger RNA was observed in the lungs of obese rats compared to that in nonobese rats following DEP exposure. These data indicate that the DEP-exposed OLETF group had increased airway responses and inflammation compared to the DEP-exposed LETO group, indicating that diesel particulates and obesity may be co-contributors to asthma.
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Affiliation(s)
- Kuk-Young Moon
- Department of Internal Medicine, Division of Allergy and Respiratory Diseases, Soonchunhyang University Hospital, 170 Jomaru-ro, Wonmi-gu, Bucheon, Gyeonggi-Do, 420-767, Republic of Korea.
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Villegas R, Williams SM, Gao YT, Long J, Shi J, Cai H, Li H, Chen CC, Tai ES, Hu F, Cai Q, Zheng W, Shu XO. Genetic variation in the peroxisome proliferator-activated receptor (PPAR) and peroxisome proliferator-activated receptor gamma co-activator 1 (PGC1) gene families and type 2 diabetes. Ann Hum Genet 2014; 78:23-32. [PMID: 24359475 DOI: 10.1111/ahg.12044] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 09/01/2013] [Indexed: 12/30/2022]
Abstract
We used a two-stage study design to evaluate whether variations in the peroxisome proliferator-activated receptors (PPAR) and the PPAR gamma co-activator 1 (PGC1) gene families (PPARA, PPARG, PPARD, PPARGC1A, and PPARGC1B) are associated with type 2 diabetes (T2D) risk. Stage I used data from a genome-wide association study (GWAS) from Shanghai, China (1019 T2D cases and 1709 controls) and from a meta-analysis of data from the Asian Genetic Epidemiology Network for T2D (AGEN-T2D). Criteria for selection of single nucleotide polymorphisms (SNPs) for stage II were: (1) P < 0.05 in single marker analysis in Shanghai GWAS and P < 0.05 in the meta-analysis or (2) P < 10(-3) in the meta-analysis alone and (3) minor allele frequency ≥ 0.10. Nine SNPs from the PGC1 family were assessed in stage II (an independent set of middle-aged men and women from Shanghai with 1700 T2D cases and 1647 controls). One SNP in PPARGC1B, rs251464, was replicated in stage II (OR = 0.87; 95% CI: 0.77-0.99). Gene-body mass index (BMI) and gene-exercise interactions and T2D risk were evaluated in a combined dataset (Shanghai GWAS and stage II data: 2719 cases and 3356 controls). One SNP in PPARGC1A, rs12640088, had a significant interaction with BMI. No interactions between the PPARGC1B gene and BMI or exercise were observed.
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Affiliation(s)
- Raquel Villegas
- Vanderbilt Epidemiology Center, Vanderbilt University Medical Center, Nashville, TN, USA
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Functional crosstalk of PGC-1 coactivators and inflammation in skeletal muscle pathophysiology. Semin Immunopathol 2013; 36:27-53. [DOI: 10.1007/s00281-013-0406-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 10/29/2013] [Indexed: 02/06/2023]
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Civelek M, Hagopian R, Pan C, Che N, Yang WP, Kayne PS, Saleem NK, Cederberg H, Kuusisto J, Gargalovic PS, Kirchgessner TG, Laakso M, Lusis AJ. Genetic regulation of human adipose microRNA expression and its consequences for metabolic traits. Hum Mol Genet 2013; 22:3023-37. [PMID: 23562819 DOI: 10.1093/hmg/ddt159] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The genetics of messenger RNA (mRNA) expression has been extensively studied in humans and other organisms, but little is known about genetic factors contributing to microRNA (miRNA) expression. We examined natural variation of miRNA expression in adipose tissue in a population of 200 men who have been carefully characterized for metabolic syndrome (MetSyn) phenotypes as part of the Metabolic Syndrome in Men (METSIM) study. We genotyped the subjects using high-density single-nucleotide polymorphism microarrays and quantified the mRNA abundance using genome-wide expression arrays and miRNA abundance using next-generation sequencing. We reliably quantified 356 miRNA species that were expressed in human adipose tissue, a limited number of which made up most of the expressed miRNAs. We mapped the miRNA abundance as an expression quantitative trait and determined cis regulation of expression for nine of the miRNAs and of the processing of one miRNA (miR-28). The degree of genetic variation of miRNA expression was substantially less than that of mRNAs. For the majority of the miRNAs, genetic regulation of expression was independent of the expression of mRNA from which the miRNA is transcribed. We also showed that for 108 miRNAs, mapped reads displayed widespread variation from the canonical sequence. We found a total of 24 miRNAs to be significantly associated with MetSyn traits. We suggest a regulatory role for miR-204-5p which was predicted to inhibit acetyl coenzyme A carboxylase β, a key fatty acid oxidation enzyme that has been shown to play a role in regulating body fat and insulin resistance in adipose tissue.
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Affiliation(s)
- Mete Civelek
- Department of Medicine, University of California, Los Angeles, CA 90095, USA
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Piantadosi CA, Suliman HB. Redox regulation of mitochondrial biogenesis. Free Radic Biol Med 2012; 53:2043-53. [PMID: 23000245 PMCID: PMC3604744 DOI: 10.1016/j.freeradbiomed.2012.09.014] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 09/07/2012] [Accepted: 09/11/2012] [Indexed: 12/21/2022]
Abstract
The cell renews, adapts, or expands its mitochondrial population during episodes of cell damage or periods of intensified energy demand by the induction of mitochondrial biogenesis. This bigenomic program is modulated by redox-sensitive signals that respond to physiological nitric oxide (NO), carbon monoxide (CO), and mitochondrial reactive oxygen species production. This review summarizes our current ideas about the pathways involved in the activation of mitochondrial biogenesis by the physiological gases leading to changes in the redox milieu of the cell, with an emphasis on the responses to oxidative stress and inflammation. The cell's energy supply is protected from conditions that damage mitochondria by an inducible transcriptional program of mitochondrial biogenesis that operates in large part through redox signals involving the nitric oxide synthase and the heme oxygenase-1/CO systems. These redox events stimulate the coordinated activities of several multifunctional transcription factors and coactivators also involved in the elimination of defective mitochondria and the expression of counterinflammatory and antioxidant genes, such as IL10 and SOD2, as part of a unified damage-control network. The redox-regulated mechanisms of mitochondrial biogenesis schematically outlined in the graphical abstract link mitochondrial quality control to an enhanced capacity to support the cell's metabolic needs while improving its resistance to metabolic failure and avoidance of cell death during periods of oxidative stress.
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Affiliation(s)
- Claude A Piantadosi
- Department of Medicine, Duke University Medical Center and the Durham VA Medical Center, Durham, NC 27710, USA.
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21
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Piantadosi CA, Suliman HB. Transcriptional control of mitochondrial biogenesis and its interface with inflammatory processes. Biochim Biophys Acta Gen Subj 2012; 1820:532-41. [PMID: 22265687 DOI: 10.1016/j.bbagen.2012.01.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 12/23/2011] [Accepted: 01/07/2012] [Indexed: 12/28/2022]
Abstract
BACKGROUND Cells avoid major mitochondrial damage and energy failure during systemic inflammatory states, such as severe acute infections, by specific targeting of the inflammatory response and by inducing anti-inflammatory and anti-oxidant defenses. Recent evidence indicates that these cell defenses also include mitochondrial biogenesis and the clearance of damaged mitochondria through autophagy. SCOPE OF REVIEW This review addresses a group of transcriptional signaling mechanisms that engage mitochondrial biogenesis, including energy-sensing and redox-regulated transcription factors and co-activators, after major inflammatory events. MAJOR CONCLUSIONS Stimulation of the innate immune system by activation of toll-like receptors (TLR) generates pro-inflammatory mediators, such as tumor necrosis factor-α (TNF-α)and interleukin-1β (IL-1β), necessary for optimal host defense, but which also contribute to mitochondrial damage through oxidative stress and other mechanisms. To protect its energy supply, host cells sense mitochondrial damage and initiate mitochondrial biogenesis under the control of an inducible transcriptional program that also activates anti-oxidant and anti-inflammatory gene expression. This multifunctional network not only increases cellular resistance to metabolic failure, oxidative stress, and cell death, but promotes immune tolerance as shown in the graphical abstract. GENERAL SIGNIFICANCE The post-inflammatory induction of mitochondrial biogenesis supports metabolic function and cell viability while helping to control inflammation. In clinical settings, patients recovering from severe systemic infections may develop transient immune suppression, placing them at risk for recurrent infection, but there may be therapeutic opportunities to enhance mitochondrial quality control that would improve the resolution of life-threatening host responses to such infections.
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Affiliation(s)
- Claude A Piantadosi
- Department of Medicine, Duke University Medical Center, and Durham VA Medical Center, Durham, NC 27710, USA.
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22
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Lee SH, Jang AS, Woo Park S, Park JS, Kim YK, Uh ST, Kim YH, Chung IY, Park BL, Shin HD, Park CS. Genetic effect of single-nucleotide polymorphisms in the PPARGC1B gene on airway hyperreactivity in asthmatic patients. Clin Exp Allergy 2011; 41:1533-44. [PMID: 21692888 DOI: 10.1111/j.1365-2222.2011.03801.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Peroxisome proliferator-activated receptor gamma coactivator 1 beta (PPARGC1B) is a co-activator for intracellular receptors such as the estrogen receptor, PPAR, and glucocorticoid receptor, which are involved in asthma development. OBJECTIVES Genetic association of single-nucleotide polymorphisms (SNPs) in the PPARGC1B gene with the risk of asthma and airway hyperreactivity (AHR) was investigated, as well as the functional effects of these SNPs on PPARGC1B gene and protein expression. METHODS Direct sequencing of DNA from 24 Korean was performed to identify PPARGC1B SNPs. Genotyping was done in 264 controls and 949 asthmatics using single-base extension methods. PPARGC1B mRNA levels were measured using real-time PCR methodology. Luciferase and electrophoretic mobility shift assays (EMSA) were performed to functionally analyse PPARGC1B SNPs on promoter. RESULTS Eighteen SNPs and one insertion/deletion polymorphism were identified, and seven SNPs were genotyped. No significant difference existed in the distribution of SNPs and haplotypes between the asthmatics and controls. However, the allele frequency of -427C>T and +102525G>A;R265Q showed a significant association with log-transformed PC(20) methacholine values in the asthmatics (P=0.005-0.0004). Real-time PCR demonstrated higher PPARGC1B mRNA levels in asthmatics having -427CC allele than in those having -427TT or CT alleles (P=0.048). The ratio of the mRNA expression for each PPARGC1B exon4-mRNA compared with the wild type was similar in peripheral blood mononuclear cells carrying the +102525G>A allele. Luciferase reporter assays revealed that -427C allele caused higher promoter activity than -427T allele. EMSA demonstrated that -427C allele exhibited stronger binding activity to a nuclear protein in 293T cells than did the -427T allele. CONCLUSIONS AND CLINICAL RELEVANCE Polymorphisms of -427C>T on the promoter and those of +102525G>A on exon 5 of the PPARGC1B gene may affect the development of AHR through the modulation of PPARGC1B gene products. The PPARGC1B genotypes may serve as genetic markers for AHR.
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Affiliation(s)
- S-H Lee
- Genome Research Center for Allergy and Respiratory disease, Soonchunhyang University Hospital, Wonmi-gu, Bucheon, Gyeonggi-do, Republic of Korea
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Abstract
PURPOSE OF REVIEW The review highlights recent findings regarding the functions of mitochondria in adipocytes, providing an understanding of their central roles in regulating substrate metabolism, energy expenditure, disposal of reactive oxygen species (ROS), and in the pathophysiology of obesity and insulin resistance, as well as roles in the mechanisms that affect adipogenesis and mature adipocyte function. RECENT FINDINGS Nutrient excess leads to mitochondrial dysfunction, which in turn leads to obesity-related pathologies, in part due to the harmful effects of ROS. The recent recognition of 'ectopic' brown adipose in humans suggests that this tissue may play an underappreciated role in the control of energy expenditure. Transcription factors, PGC-1alpha and PRDM16, which regulate brown adipogenesis, and members of the TGF-beta superfamily that modulate this process may be important new targets for antiobesity drugs. SUMMARY Mitochondria play central roles in ATP production, energy expenditure, and disposal of ROS. Excessive energy substrates lead to mitochondrial dysfunction with consequential effects on lipid and glucose metabolism. Adipocytes help to maintain the appropriate balance between energy storage and expenditure and maintaining this balance requires normal mitochondrial function. Many adipokines, including members of the TGF-beta superfamily, and transcriptional coactivators, PGC-1alpha and PRDM16, are important regulators of this process.
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Affiliation(s)
- Juan C. Bournat
- Department of Molecular and Human Genetics, Houston, TX 77030, USA
| | - Chester W. Brown
- Department of Molecular and Human Genetics, Houston, TX 77030, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children’s Hospital, Houston, TX 77030, USA
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Estep M, Armistead D, Hossain N, Elarainy H, Goodman Z, Baranova A, Chandhoke V, Younossi ZM. Differential expression of miRNAs in the visceral adipose tissue of patients with non-alcoholic fatty liver disease. Aliment Pharmacol Ther 2010; 32:487-97. [PMID: 20497147 DOI: 10.1111/j.1365-2036.2010.04366.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Progression of non-alcoholic fatty liver disease (NAFLD) can be facilitated by soluble molecules secreted by visceral adipose tissue (VAT). MicroRNAs (miRNAs) are likely to regulate some of these molecular pathways involved in pathogenesis of NAFLD. AIM To profile miRNA expression in the visceral adipose tissue of patients with NAFLD. METHODS Visceral adipose tissue samples were collected from NAFLD patients and frozen. Patients with biopsy-proven NAFLD were divided into non-alcoholic steatohepatitis (NASH) (n = 12) and non-NASH (n = 12) cohorts controlled for clinical and demographic characteristics. Extracted total RNA was profiled using TaqMan Human MicroRNA arrays. Univariate Mann-Whitney comparisons and multivariate regression analysis were performed to compare miRNA profiles. RESULTS A total of 113 miRNA differentially expressed between NASH patients and non-NASH patients (P < 0.05). Of these, seven remained significant after multiple test correction (hsa-miR-132, hsa-miR-150, hsa-miR-433, hsa-miR-28-3p, hsa-miR-511, hsa-miR-517a, hsa-miR-671). Predicted target genes for these miRNAs include insulin receptor pathway components (IGF1, IGFR13), cytokines (CCL3, IL6), ghrelin/obestatin gene, and inflammation-related genes (NFKB1, RELB, FAS). In addition, two miRNA species, hsa-miR-197 and hsa-miR-99, were significantly associated with pericellular fibrosis in NASH patients (P < 0.05). Levels of IL-6 in the serum negatively correlated with the expression levels of all seven miRNAs capable of down regulating IL-6 encoding gene. CONCLUSIONS miRNA expression from VAT may contribute to the pathogenesis of NAFLD - a finding which may distinguish relatively simple steatosis from NASH. This could help identify potential targets for pharmacological treatment regimens and candidate biomarkers for NASH.
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Affiliation(s)
- M Estep
- Betty and Guy Beatty Center for Integrated Research, Falls Church, VA 22042, USA
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25
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Abstract
The genetic contribution to interindividual variation in common obesity has been estimated at 40-70%. Yet, despite a relatively high heritability, the search for obesity susceptibility genes has been an arduous task. This paper reviews recent progress made in the obesity genetics field with an emphasis on established obesity susceptibility loci identified through candidate gene as well as genome-wide studies. For the last 15 years, candidate gene and genome-wide linkage studies have been the two main genetic epidemiological approaches to identify genetic loci for common traits, yet progress has been slow and success limited. Only recently have candidate gene studies started to succeed; by means of large-scale studies and meta-analyses at least five variants in four candidate genes have been found to be robustly associated with obesity-related traits. Genome-wide linkage studies, however, have so far not been able to pinpoint genetic loci for common obesity. The genome-wide association approach, which has become available in recent years, has dramatically changed the pace of gene discoveries for common disease, including obesity. Three waves of large-scale high-density genome-wide association studies have already discovered at least 15 previously unanticipated genetic loci incontrovertibly associated with body mass index and extreme obesity risk. Although the combined contribution of these loci to the variation in obesity risk at the population level is small and their predictive value is typically low, these recently discovered loci are set to improve fundamentally our insights into the pathophysiology of obesity.
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Affiliation(s)
- Ruth J F Loos
- MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
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26
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Delhon I, Gutzwiller S, Morvan F, Rangwala S, Wyder L, Evans G, Studer A, Kneissel M, Fournier B. Absence of estrogen receptor-related-alpha increases osteoblastic differentiation and cancellous bone mineral density. Endocrinology 2009; 150:4463-72. [PMID: 19608650 DOI: 10.1210/en.2009-0121] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The nuclear orphan receptor human estrogen receptor-related receptor (ERR)-alpha is implicated in bone metabolism. We studied the effect of ERRalpha silencing in human mesenchymal stem cells (hMSCs) during osteoblastogenesis. We found that ERRalpha silencing led to an increase of bone sialoprotein and a decrease of osteopontin mRNA levels, suggesting enhanced osteoblastic differentiation. This was confirmed by an increased ability of hMSCs to deposit calcium. Concomitantly, knockdown of ERRalpha inhibited adipogenesis, resulting in a decrease in adipocyte number and adipocyte marker gene expression. In line with a negative role of ERRalpha in bone metabolism, we found that adult female and male ERRalpha-deficient mice displayed a moderate increase in femoral cancellous bone volume and density. Osteoblast surface was increased and marrow fat volume decreased in these animals. Furthermore, ERRalpha-deficient osteoblasts displayed increased differentiation properties in vitro in line with our observations in hMSCs. In summary, we identified a role for ERRalpha in bone mass regulation by affecting osteoblastic differentiation.
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Affiliation(s)
- I Delhon
- Novartis Institutes for Biomedical Research, Musculoskeletal Diseases, 4002 Basel, Switzerland
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27
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Andreasen CH, Andersen G. Gene-environment interactions and obesity--further aspects of genomewide association studies. Nutrition 2009; 25:998-1003. [PMID: 19596186 DOI: 10.1016/j.nut.2009.06.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 06/08/2009] [Accepted: 06/08/2009] [Indexed: 12/29/2022]
Abstract
Advances in genotyping technologies have facilitated the advent of the genomewide association studies in large study populations and thereby led to the identification of an impressive-and still increasing-number of genetic variants with significant impact on the risk of widespread lifestyle health problems such as obesity, diabetes, and cardiovascular disease. Yet, the scientific community is a long way from reaching a comprehensive picture of the heritable components of these diseases and advancing from plain statistical significance into a biological understanding where the true contribution to a trait is recognized. Increasingly large study populations, denser single-nucleotide polymorphism mapping, deep sequencing, and raised awareness of the importance of structural variants may add to the known genetic variance underlying common complex disorders; however, genetic variance alone probably cannot account for disease susceptibility without the addition of pre- and postnatal environmental and/or behavioral factors. Moreover, an interaction between genetic and environmental factors may hinder the detection of genetic effects if not accounted for, e.g., in genomewide association studies, and prospective cohort studies have hence been proposed to surpass the classic case-control design. With a focus on obesity we describe some of the recently reported gene-environment interactions for polymorphisms identified in the FTO and INSIG2 genes. Ultimately, a thorough understanding of the gene-environment interactions underlying a common complex condition such as obesity may suggest novel treatment or intervention strategies to complement the harmful effect of detrimental genetic variation and thus may assist in improving the quality of life for affected individuals.
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28
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Holloway GP, Bonen A, Spriet LL. Regulation of skeletal muscle mitochondrial fatty acid metabolism in lean and obese individuals. Am J Clin Nutr 2009; 89:455S-62S. [PMID: 19056573 DOI: 10.3945/ajcn.2008.26717b] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A reduction in fatty acid (FA) oxidation has been associated with lipid accumulation and insulin resistance in skeletal muscle of obese individuals. Numerous reports suggest that the reduction in FA oxidation may result from intrinsic mitochondrial defects, although little direct evidence has been offered to support this conclusion. This brief review summarizes recent work from our laboratory that reexamined whether this decrease in skeletal muscle FA oxidation with obesity was attributable to a dysfunction in FA oxidation within mitochondria or simply to a reduction in muscle mitochondrial content. Whole-muscle mitochondrial content and FA oxidation was reduced in the obese, but there was no decrease in the ability of isolated mitochondria to oxidize FA. The mitochondrial content of the transport protein, FA translocase (FAT/CD36), did not differ between lean and obese women but was correlated with mitochondrial FA oxidation. It was concluded that the reduced FA oxidation in obesity is attributable to decreased muscle mitochondrial content and not intrinsic defects in mitochondrial FA oxidation, and that mitochondrial FAT/CD36 is involved in regulating FA oxidation in human skeletal muscle. The reduced skeletal muscle mitochondrial content with obesity may result from impaired mitochondrial biogenesis. However, this did not result from decreased protein contents of various transcription factors, because peroxisome proliferater-activated receptor gamma coactivator 1alpha (PGC1alpha), PGC1beta, peroxisome proliferator-activated receptor alpha (PPARalpha), and mitochondrial transcription factor A (TFAM) were not reduced with obesity. In contrast, it appears that obesity is associated with altered regulation of cofactors (PGC1alpha and PGC1beta) and their downstream transcription factors (PPARalpha, PPARdelta/beta, and TFAM), because relations among these variables were present in muscle from lean individuals but not from obese individuals. These findings imply that obese individuals would benefit from interventions that increase the skeletal muscle mitochondrial content and the potential for oxidizing FAs.
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Affiliation(s)
- Graham P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
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29
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Oberkofler H, Hafner M, Felder T, Krempler F, Patsch W. Transcriptional co-activator peroxisome proliferator-activated receptor (PPAR)gamma co-activator-1beta is involved in the regulation of glucose-stimulated insulin secretion in INS-1E cells. J Mol Med (Berl) 2008; 87:299-306. [PMID: 19082571 DOI: 10.1007/s00109-008-0425-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 11/17/2008] [Accepted: 11/26/2008] [Indexed: 01/01/2023]
Abstract
Peroxisome proliferator-activated receptor-gamma co-activator-1 (PGC-1) alpha and -beta play pivotal roles in the regulation of intermediary metabolism. We have previously shown that PGC-1alpha-mediated upregulation of beta-cell sterol element binding protein (SREBP) gene expression impairs insulin secretion via increased transcription of uncoupling protein 2 (UCP2). PGC-1beta, in contrast to PGC-1alpha, directly binds to and acts as a co-activator of SREBPs and the forkhead transcription factor 2A (FOXA2) involved in pancreas development and function. To address a possible role of PGC-1beta in beta-cell function, we determined islet gene expression levels of PGC-1alpha, PGC-1beta, SREBPs, FOXA2, FOXO1, UCP2 as well as granuphilin, a critical component of the insulin secretory machinery, in Zucker diabetic fatty rats (ZDF). In comparison to controls, mRNA levels of all genes studied except for FOXA2 and FOXO1 were increased in islets of obese, fa/fa ZDF rats. The transcriptional activities of the UCP2 and granuphilin promoters were assessed in INS-1E cells in response to PGC-1beta overexpression and small interference RNA (siRNA)-mediated gene silencing. PGC-1beta as well as SREBP-1c and -2 increased transcription from the UCP2 promoter in INS-1E cells. Transient transfection of PGC-1beta-specific siRNAs significantly decreased SREBP-2-mediated transcriptional activation of the UCP2 gene. Furthermore PGC-1beta, SREBP-1c, and FOXA2 overexpression augmented granuphilin promoter activity, whereas siRNA-mediated gene knockdown of PGC-1beta reduced the effects of SREBP-1c and FOXA2 on granuphilin gene transcription and significantly increased glucose-stimulated insulin release from INS-1E cells. Our results support a role of PGC-1beta in the regulation of insulin secretion via upregulation of UCP2 and granuphilin gene expression.
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Affiliation(s)
- Hannes Oberkofler
- Department of Laboratory Medicine, Landeskliniken and Paracelsus Private Medical University Salzburg, Müllner Hauptstr., Austria.
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30
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Holloway GP, Perry CGR, Thrush AB, Heigenhauser GJF, Dyck DJ, Bonen A, Spriet LL. PGC-1alpha's relationship with skeletal muscle palmitate oxidation is not present with obesity despite maintained PGC-1alpha and PGC-1beta protein. Am J Physiol Endocrinol Metab 2008; 294:E1060-9. [PMID: 18349111 DOI: 10.1152/ajpendo.00726.2007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Reduced skeletal muscle mitochondrial content and fatty acid oxidation are associated with obesity and insulin resistance. Although the exact mechanisms remain elusive, this may result from impaired mitochondrial biogenesis or reductions in the mitochondrial reticulum network. Therefore, the purpose of this study was to determine whether the protein contents of various transcription factors, including PGC-1alpha and PGC-1beta and proteins associated with mitochondrial fusion events, were reduced in skeletal muscle of nine obese (BMI = 37.6 +/- 2.2 kg/m(-2)) compared with nine age-matched lean (BMI = 23.3 +/- 0.7 kg/m(-2)) women. The protein contents of PGC-1alpha, PGC-1beta, PPARalpha, and tFAM were not reduced with obesity. In contrast, PPARgamma was increased (+22%, P < 0.05) with obesity, and there was a trend toward an increase (+31%, P = 0.13) in PPARdelta/beta. In lean individuals, PGC-1alpha protein correlated with citrate synthase (CS; r = 0.67) and rates of palmitate oxidation (r = 0.87), whereas PGC-1beta correlated with PPARgamma (r = 0.90), PPARdelta/beta (r = 0.63), and cytochrome c oxidase IV (COX-IV; r = 0.63). In obese individuals, the relationship between PGC-1alpha and CS was maintained (r = 0.65); however, the associations between PGC-1alpha and palmitate oxidation (r = -0.38) and PGC-1beta with PPARgamma (r = 0.14), PPARdelta/beta (r = 0.21), and COX-IV (r = 0.01) were lost. In addition, mitofusin-1 (MFN-1), MFN-2, and dynamin-related protein-1 (DRP-1) total protein contents were not altered with obesity (P > 0.05). These data suggest that altered regulation, and not reductions in the protein contents of transcription factors, is associated with insulin resistance. Also, it does not appear that alterations in the proteins associated with mitochondrial network formation and degradation can account for the observed decrease in mitochondrial content.
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Affiliation(s)
- Graham P Holloway
- Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada.
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31
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Abstract
PURPOSE OF REVIEW The purpose of this review is to summarize the recent literature regarding the familial heritability of heart failure and to discuss the possible mechanisms through which this risk is mediated. RECENT FINDINGS Data from the Framingham Heart Study recently showed that the parental occurrence of heart failure increases the risk of heart failure in offspring. Although the mechanisms mediating this increased risk are not elucidated, heritable risks of heart failure may result from genes affecting the cardiac or vascular systems. Alternatively, familial risk may be mediated partly through the inheritance of recognized or as yet unidentified risk factors for heart failure. Heritable components or genetic loci for quantitative traits contribute to the development of hypertension, coronary artery disease, cardiomyopathies, valvular heart disease, and metabolic conditions, which collectively increase the risk of heart failure. SUMMARY A careful assessment of the family history of heart failure and associated risk factors may identify treatable targets that can potentially reduce the likelihood of developing heart failure, and can assist in the implementation of preventive strategies for risk populations with stages A and B heart failure.
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Affiliation(s)
- Husam M Abdel-Qadir
- Faculty of Medicine, University Health Network, University of Toronto, Toronto, Canada
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32
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Ling C, Wegner L, Andersen G, Almgren P, Hansen T, Pedersen O, Groop L, Vaag A, Poulsen P. Impact of the peroxisome proliferator activated receptor-gamma coactivator-1beta (PGC-1beta) Ala203Pro polymorphism on in vivo metabolism, PGC-1beta expression and fibre type composition in human skeletal muscle. Diabetologia 2007; 50:1615-20. [PMID: 17579828 DOI: 10.1007/s00125-007-0729-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Accepted: 04/30/2007] [Indexed: 10/23/2022]
Abstract
AIMS/HYPOTHESIS Peroxisome proliferator activated receptor-gamma coactivator-1beta (PGC-1beta, also known as PPARGC1B) expression is reduced in skeletal muscle from patients with type 2 diabetes mellitus and in elderly subjects. Ala203Pro, a common variant in the PGC-1beta gene is associated with obesity. The aim of this study was to investigate whether the PGC-1beta Ala203Pro polymorphism influences the age-related decline in skeletal muscle PGC-1beta expression, in vivo metabolism and markers for muscle fibre type composition. MATERIALS AND METHODS The PGC-1beta Ala203Pro polymorphism was genotyped in 110 young (age 28.0 +/- 1.9 years) and 86 elderly (age 62.4 +/- 2.0 years) twins and related to muscle PGC-1beta expression, in vivo metabolism and markers for fibre type composition. RESULTS Insulin-stimulated non-oxidative glucose metabolism (NOGM; p = 0.025) and glycolytic flux rate (GF; p = 0.026) were reduced in young Ala/Ala carriers compared with carriers of a 203Pro allele. In addition, a regression analysis, correcting for covariates, showed that the PGC-1beta 203Pro allele was positively related to insulin-stimulated NOGM and GF in the young twins. While muscle expression of PGC-1beta was reduced in elderly compared with young carriers of the Ala/Ala genotype (p < or = 0.001), there was no significant age-related decline in PGC-1beta expression in carriers of the 203Pro allele (p > or = 0.4). However, a regression analysis, correcting for covariates, showed that only age was significantly related to muscle PGC-1beta expression. Finally, PGC-1beta expression correlated positively with markers for oxidative fibres in human muscle. CONCLUSIONS/INTERPRETATION This study suggests that young carriers of a PGC-1beta 203Pro allele have enhanced insulin-stimulated glucose metabolism and may be protected against an age-related decline in PGC-1beta expression in muscle.
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Affiliation(s)
- C Ling
- Department of Clinical Sciences/Diabetes and Endocrinology, Lund University, CRC, University Hospital MAS, 205 02 Malmo, Sweden.
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33
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Li D, Kang Q, Wang DM. Constitutive coactivator of peroxisome proliferator-activated receptor (PPARgamma), a novel coactivator of PPARgamma that promotes adipogenesis. Mol Endocrinol 2007; 21:2320-33. [PMID: 17595322 DOI: 10.1210/me.2006-0520] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Peroxisome proliferator-activated receptor gamma (PPARgamma) plays essential roles in adipogenesis by transcriptionally regulating adipocyte-specific genes through recruitment of coregulators including coactivators and corepressors. However, the precise repertoire of coactivators required for PPARgamma transactivation remains unresolved. In this report, we cloned and characterized a novel PPARgamma interacting protein, constitutive coactivator of PPARgamma (CCPG), which is expressed in multiple adult tissues and throughout embryonic development. CCPG is localized in nucleus and contains four LXXLL motifs, which are characteristic for nuclear receptor coactivators. A delineation of CCPG-PPARgamma interaction by glutathione-S-transferase pull-down and coimmunoprecipitation assays indicated that CCPG interacts with the hinge region of PPARgamma in a ligand-independent manner. However, mutation of four motifs of LXXLL to LXXAA in CCPG does not compromise its interaction with PPARgamma, suggesting LXXLL motif is not required for the interaction. Glutathione-S-transferase pull-down assays showed that CCPG binds to retinoic X receptor-alpha and estrogen receptor-alpha independent of their ligands, but not to thyroid hormone receptor-beta. CCPG coactivates PPARgamma in PPAR response element reporter assays, and the N terminus (amino acids 1-561) of CCPG acts to significantly augment the transactivation of PPARgamma, whereas the C terminus (amino acids 562-786) represses PPARgamma activity, indicating the N terminus possesses the activation domain. Using an adenoviral-mediated system, we also revealed that overexpression of CCPG promoted differentiation of OP9 preadipocyte into adipocyte, and knockdown of CCPG by RNA interference blocked this process, as examined by Oil Red O staining and Western blots of adipocyte-specific protein, adiponectin, and perilipin. Taken together, our data indicate that CCPG is a bona fide coactivator and promotes adipogenesis in a PPARgamma-dependent manner.
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Affiliation(s)
- Dechun Li
- Department of Internal Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Saint Louis University, Desloge Towers, Seventh Floor, 3635 Vista Avenue, St. Louis, Missouri 63110-0250, USA.
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Abstract
Obesity is the result of an imbalance between food intake and energy expenditure resulting in the storing of energy as fat. Adipose tissue contains the largest store of energy in the body and plays important roles in regulating energy partitioning. Developments in genomics, in particular microarray-based expression profiling, have provided scientists with a number of new candidate genes whose expression in adipose tissue is regulated by obesity. Integrating expression profiles with genome-wide linkage and/or association analyses is a promising strategy to identify new genes underlying susceptibility to obesity. This article provides a comprehensive review of adipose-tissue-expressed genes implicated in predisposition to human obesity. The authors consider the following genes of particular interest: peroxisome proliferator-activated receptor gamma and, potentially, INSIG2 acting in adipogenesis; the adrenoreceptors beta 2 and 3, as well as hormone-sensitive lipase acting on lipolysis; uncoupling protein 2 acting in mitochondria energy expenditure; and among secreted molecules the cytokine tumor necrosis factor alpha and the hormone leptin. With the rapid development in genome research, we predict that additional alleles in genes regulating adipose tissue function will be established as risk factors for common obesity in the coming years. This has important implications for the prevention of obesity and may also offer new therapeutic targets.
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Affiliation(s)
- I Dahlman
- Department of Medicine, Huddinge, Karolinska Institute, Stockholm, Sweden.
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Dahlman I, Dicker A, Jiao H, Kere J, Blomqvist L, van Harmelen V, Hoffstedt J, Borch-Johnsen K, Jorgensen T, Hansen T, Pedersen O, Laakso M, Arner P. A common haplotype in the G-protein-coupled receptor gene GPR74 is associated with leanness and increased lipolysis. Am J Hum Genet 2007; 80:1115-24. [PMID: 17503329 PMCID: PMC1867099 DOI: 10.1086/518445] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 03/21/2007] [Indexed: 11/03/2022] Open
Abstract
The G-protein-coupled receptor GPR74 is a novel candidate gene for body weight regulation. In humans, it is predominantly expressed in brain, heart, and adipose tissue. We report a haplotype in the GPR74 gene, ATAG, with allele frequency ~4% in Scandinavian cohorts, which was associated with protection against obesity in two samples selected for obese and lean phenotypes (odds ratio for obesity 0.48 and 0.62; nominal P=.0014 and .014; n=1,013 and 1,423, respectively). In a population-based sample, it was associated with lower waist (P=.02) among 3,937 men and with obesity protection (odds ratio 0.36; P=.036) among those selected for obese or lean phenotypes. The ATAG haplotype was associated with increased adipocyte lipid mobilization (lipolysis) in vivo and in vitro. In human fat cells, GPR74 receptor stimulation and inhibition caused a significant and marked decrease and increase, respectively, of lipolysis, which could be linked to catecholamine stimulation of adipocytes through beta -adrenergic receptors. These findings suggest that a common haplotype in the GPR74 gene protects against obesity, which, at least in part, is caused by a relief of inhibition of lipid mobilization from adipose tissue. The latter involves a cross-talk between GPR74 and beta -adrenoceptor signaling to lipolysis in fat cells.
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Affiliation(s)
- Ingrid Dahlman
- Department of Medicine, Karolinska University Hospital, Huddinge, Stockholm, Sweden
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Krämer DK, Ahlsén M, Norrbom J, Jansson E, Hjeltnes N, Gustafsson T, Krook A. Human skeletal muscle fibre type variations correlate with PPAR alpha, PPAR delta and PGC-1 alpha mRNA. Acta Physiol (Oxf) 2006; 188:207-16. [PMID: 17054660 DOI: 10.1111/j.1748-1716.2006.01620.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Studies from genetically modified animals have been instrumental in highlighting genes and their products involved in the regulation of muscle fibre type and oxidative phenotypes; however, evidence in humans is limited. Our aim was therefore to investigate expression of those genes implicated in the regulation of oxidative fibre phenotypes in humans. METHODS Using quantitative polymerase chain reaction we determined mRNA expression of selected genes in skeletal muscle from three different groups, displaying physiological and pathological variations in muscle fibre type, activity and skeletal muscle metabolism respectively: (i) elite athletes (cyclists), with an increased proportion of type I slow twitch, oxidative fibres, (ii) normally active subjects with an average fibre type distribution, and (iii) spinal cord-injured subjects with a low proportion of type I fibres. RESULTS Skeletal muscle mRNA expression of calcineurin Aalpha and Abeta, peroxisome proliferator-activated receptor (PPAR)-alpha and -delta, and PPAR gamma coactivator (PGC)-1alpha and -1beta was determined. Calcineurin Aalpha and calcineurin Abeta mRNA expression was similar between groups. In contrast, mRNA expression of PPARalpha, PPARdelta, PGC-1alpha and -1beta was increased in athletes, when compared with normally active subjects. Furthermore, mRNA expression of PPARalpha, PPARdelta, PGC-1alpha and -1beta was reduced in spinal cord-injured subjects. Additionally, PPARalpha, PPARdelta and PGC-1alpha correlated with oxidative fibre content. CONCLUSION Skeletal muscle mRNA expression of PPARalpha, PPARdelta, PGC-1alpha and -1beta reflects differences in type I muscle fibres associated with pathologically and physiologically induced skeletal muscle fibre type differences.
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Affiliation(s)
- D K Krämer
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
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Larsen LH, Rose CS, Sparsø T, Overgaard J, Torekov SS, Grarup N, Jensen DP, Albrechtsen A, Andersen G, Ek J, Glümer C, Borch-Johnsen K, Jørgensen T, Hansen T, Pedersen O. Genetic analysis of the estrogen-related receptor α and studies of association with obesity and type 2 diabetes. Int J Obes (Lond) 2006; 31:365-70. [PMID: 16755280 DOI: 10.1038/sj.ijo.0803408] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The estrogen-related receptor alpha (ERRalpha or NR3B1) is a transcription factor from the nuclear receptor super-family, group III. The gene encoding ERRalpha (ESRRA) is located on chromosome 11q13, a region showing genetic linkage to body mass index and fat percentage. Through interaction with the peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha), ERRalpha regulates key enzymes involved in the beta-oxidation of fatty acids. RESULTS By screening 48 overweight or obese subjects for variants in the exons, exon-intron boundaries and 1000 base pairs (bp) of the promoter region of ESRRA using bi-directional nucleotide sequencing, we identified seven variants. Four rare variants had minor allele frequencies (MAF) below 1%: Pro369Pro, Gly406Asp, 3'UTR+418G>A, 3'UTR+505C>A. Two single-nucleotide polymorphisms, Pro116Pro and IVS6+65C>T (MAF 15%), were in complete linkage disequilibrium (LD) (r (2)=1). We also confirmed the presence of a reported 23 bp microsatellite repeat (ESRRA23). The Pro116Pro and ESRRA23 variants were not associated with obesity, type 2 diabetes or related phenotypes in a large population-based study of 6365 Danish whites. The two variants were examined for interactions with variants in the peroxisome proliferator-activated receptor-gamma coactivator-1alpha and -beta; however, no evidence of epistatic effects between the variants was demonstrated. CONCLUSION The ESRRA23 and Pro116Pro variants of the gene encoding ERRalpha are not associated with obesity, type 2 diabetes or related quantitative traits in the examined Danish whites.
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Affiliation(s)
- L H Larsen
- Steno Diabetes Center, Gentofte, Denmark
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Park KS, Shin HD, Park BL, Cheong HS, Cho YM, Lee HK, Lee JY, Lee JK, Kim HT, Park CS, Han BG, Kimm K, Oh B. Putative association of peroxisome proliferator-activated receptor gamma co-activator 1beta (PPARGC1B) polymorphism with Type 2 diabetes mellitus. Diabet Med 2006; 23:635-42. [PMID: 16759305 DOI: 10.1111/j.1464-5491.2006.01882.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIMS Peroxisome proliferator-activated receptor gamma co-activator 1beta (PPARGC1B) may play an important role in obesity and Type 2 diabetes mellitus (T2DM). In an effort to identify genetic polymorphisms in potential candidate genes for T2DM, genetic associations of PPARGC1B were examined in a Korean T2DM study. METHODS We have sequenced the PPARGC1B, and examined its association with T2DM and diabetic phenotypes in a Korean T2DM study (775 T2DM patients and 316 control subjects) using the TaqMan method. Logistic and multiple regression models were employed to analyse the genetic contributions of polymorphisms. Nineteen polymorphisms were identified in PPARGC1B. RESULTS By logistic regression analysis controlling for age and sex as covariates, one non-synonymous single-nucleotide polymorphism (SNP; +102605C>A; Arg292Ser) in exon 5 showed marginal significant associations with the risk of T2DM. The allele frequency of the minor allele ['A (= Ser)' allele of +102605C>A] was lower among T2DM patients (frequency = 0.101) than among control subjects (frequency = 0.135) [P = 0.03, OR = 0.71 (95% CI: 0.51-0.94)]. Furthermore, serum triglyceride level was also associated with this non-synonymous SNP (+102605C>A; Arg292Ser) in exon 5 among controls (P = 0.03 in the dominant analysing model). Serum triglyceride levels [1.46 +/- 0.70 (log-transformed value; 0.12 +/- 0.18)] were lower in individuals who carry one or two copies of minor alleles than among others [1.60 +/- 0.85 (log-transformed value; 0.16 +/- 0.21)]. CONCLUSION The present study provides, for the first time, information about genetic polymorphisms in PPARGC1B and putative associations of one non-synonymous SNP with the risk of T2DM and serum triglyceride (TG) levels in the Korean population, although this result was not significant after correction for multiple testing.
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Affiliation(s)
- K S Park
- Genome Research Center for Diabetes and Endocrine Disease, Clinical Research Institute, Seoul National University Hospital, Korea
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