1
|
Ding K, Liu C, Li L, Yang M, Jiang N, Luo S, Sun L. Acyl-CoA synthase ACSL4: an essential target in ferroptosis and fatty acid metabolism. Chin Med J (Engl) 2023; 136:2521-2537. [PMID: 37442770 PMCID: PMC10617883 DOI: 10.1097/cm9.0000000000002533] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Indexed: 07/15/2023] Open
Abstract
ABSTRACT Long-chain acyl-coenzyme A (CoA) synthase 4 (ACSL4) is an enzyme that esterifies CoA into specific polyunsaturated fatty acids, such as arachidonic acid and adrenic acid. Based on accumulated evidence, the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation. Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids; ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis, respectively. In addition, ACSL4 is an essential regulator of fatty acid (FA) metabolism. ACSL4 remodels the phospholipid composition of cell membranes, regulates steroidogenesis, and balances eicosanoid biosynthesis. In addition, ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology. Because it facilitates the cross-talk between ferroptosis and FA metabolism, ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries. In this review, we focus on the structure, biological function, and unique role of ASCL4 in various human diseases. Finally, we propose that ACSL4 might be a potential therapeutic target.
Collapse
Affiliation(s)
- Kaiyue Ding
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Chongbin Liu
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Li Li
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Ming Yang
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Na Jiang
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Shilu Luo
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| | - Lin Sun
- Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410000, China
- Hunan Key Laboratory of Kidney Disease and Blood Purification, Changsha, Hunan 410000, China
| |
Collapse
|
2
|
Li S, He C, Nie H, Pang Q, Wang R, Zeng Z, Song Y. G Allele of the rs1801282 Polymorphism in PPARγ Gene Confers an Increased Risk of Obesity and Hypercholesterolemia, While T Allele of the rs3856806 Polymorphism Displays a Protective Role Against Dyslipidemia: A Systematic Review and Meta-Analysis. Front Endocrinol (Lausanne) 2022; 13:919087. [PMID: 35846293 PMCID: PMC9276935 DOI: 10.3389/fendo.2022.919087] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The relationships between the rs1801282 and rs3856806 polymorphisms in nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) gene and obesity indexes as well as serum lipid levels have been extensively investigated in various studies, but the results were inconsistent and even contradictory. METHODS PubMed, Google Scholar, Embase, Cochrane Library, Web of Science, Wanfang, CNKI and VIP databases were searched for eligible studies. The random-effTPDEects model was used, and standardized mean difference (SMD) with 95% confidence interval (CI) was calculated to estimate the differences in obesity indexes and serum lipid levels between the subjects with different genotypes in a dominant model. Heterogeneity among studies was assessed by Cochran's x2-based Q-statistic test. Publication bias was identified by using Begg's test. RESULTS One hundred and twenty studies (70,317 subjects) and 33 studies (18,353 subjects) were identified in the analyses for the rs1801282 and rs3856806 polymorphisms, respectively. The G allele carriers of the rs1801282 polymorphism had higher levels of body mass index (SMD = 0.08 kg/m2, 95% CI = 0.04 to 0.12 kg/m2, p < 0.001), waist circumference (SMD = 0.12 cm, 95% CI = 0.06 to 0.18 cm, p < 0.001) and total cholesterol (SMD = 0.07 mmol/L, 95% CI = 0.02 to 0.11 mmol/L, p < 0.01) than the CC homozygotes. The T allele carriers of the rs3856806 polymorphism had lower levels of low-density lipoprotein cholesterol (SMD = -0.09 mmol/L, 95% CI = -0.15 to -0.03 mmol/L, p < 0.01) and higher levels of high-density lipoprotein cholesterol (SMD = 0.06 mmol/L, 95% CI = 0.02 to 0.10 mmol/L, p < 0.01) than the CC homozygotes. CONCLUSIONS The meta-analysis suggests that the G allele of the rs1801282 polymorphism confers an increased risk of obesity and hypercholesterolemia, while the T allele of the rs3856806 polymorphism displays a protective role against dyslipidemia, which can partly explain the associations between these polymorphisms and cardiovascular disease. SYSTEMATIC REVIEW REGISTRATION https://www.crd.york.ac.uk/prospero/, identifier [CRD42022319347].
Collapse
Affiliation(s)
- Shujin Li
- Central Laboratory, Clinical Medical College and Affiliated Hospital of Chengdu University, Chengdu, China
| | - Chuan He
- Department of Cardiology, Clinical Medical College and Affiliated Hospital of Chengdu University, Chengdu, China
| | - Haiyan Nie
- Clinical Medical College of Chengdu University, Chengdu, China
| | - Qianyin Pang
- Clinical Medical College of Chengdu University, Chengdu, China
| | - Ruixia Wang
- Clinical Medical College of Chengdu University, Chengdu, China
| | - Zhifu Zeng
- Clinical Medical College of Chengdu University, Chengdu, China
| | - Yongyan Song
- Central Laboratory, Clinical Medical College and Affiliated Hospital of Chengdu University, Chengdu, China
- *Correspondence: Yongyan Song,
| |
Collapse
|
3
|
Duan J, Wang Z, Duan R, Yang C, Zhao R, Feng Q, Qin Y, Jiang J, Gu S, Lv K, zhang L, He B, Birnbaumer L, Yang S, Chen Z, Yang Y. Therapeutic targeting of hepatic ACSL4 ameliorates NASH in mice. Hepatology 2022; 75:140-153. [PMID: 34510514 PMCID: PMC8688219 DOI: 10.1002/hep.32148] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 08/11/2021] [Accepted: 09/03/2021] [Indexed: 01/03/2023]
Abstract
BACKGROUND AND AIMS Globally, NAFLD is one of the most common liver disorders, with an estimated prevalence rate of more than 30% in men and 15% in women and an even higher prevalence in people with type 2 diabetes mellitus. Optimal pharmacologic therapeutic approaches for NAFLD are an urgent necessity. APPROACH AND RESULTS In this study, we showed that compared with healthy controls, hepatic ACSL4 levels in patients with NAFLD were found to be elevated. Suppression of ACSL4 expression promoted mitochondrial respiration, thereby enhancing the capacity of hepatocytes to mediate β-oxidation of fatty acids and to minimize lipid accumulation by up-regulating peroxisome proliferator-activated receptor coactivator-1 alpha. Moreover, we found that abemaciclib is a potent and selective ACSL4 inhibitor, and low dose of abemaciclib significantly ameliorated most of the NAFLD symptoms in multiple NAFLD mice models. CONCLUSIONS Therefore, inhibition of ACSL4 is a potential alternative therapeutic approach for NAFLD.
Collapse
Affiliation(s)
- Jingjing Duan
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Zhuo Wang
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Ran Duan
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Chenxinhui Yang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Ruolin Zhao
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Qi Feng
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Yuanyuan Qin
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Jingwei Jiang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Shouyong Gu
- Province Geriatic Hospital, 30 Luojia Road, Nanjing 210024, China
| | - Kaiyan Lv
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Libo zhang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Bixia He
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Lutz Birnbaumer
- Institute of Biomedical Research (BIOMED), Catholic University of Argentina, Buenos Aires C1107AFF, Argentina, and Neurobiology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
| | - Song Yang
- Center of hepatology, Beijing Ditan Hospital of Capital Medical University, Beijing 100015, China
| | - Zhen Chen
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| | - Yong Yang
- Center for New Drug Safety Evaluation and Research, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, China
| |
Collapse
|
4
|
The role of genetic and epigenetic factors in non alcoholic fatty liver disease (NAFLD) pathogenesis. Meta Gene 2020. [DOI: 10.1016/j.mgene.2020.100647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
|
5
|
Singh AB, Kan CFK, Kraemer FB, Sobel RA, Liu J. Liver-specific knockdown of long-chain acyl-CoA synthetase 4 reveals its key role in VLDL-TG metabolism and phospholipid synthesis in mice fed a high-fat diet. Am J Physiol Endocrinol Metab 2019; 316:E880-E894. [PMID: 30721098 PMCID: PMC6580179 DOI: 10.1152/ajpendo.00503.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Long-chain acyl-CoA synthetase 4 (ACSL4) has a unique substrate specificity for arachidonic acid. Hepatic ACSL4 is coregulated with the phospholipid (PL)-remodeling enzyme lysophosphatidylcholine (LPC) acyltransferase 3 by peroxisome proliferator-activated receptor δ to modulate the plasma triglyceride (TG) metabolism. In this study, we investigated the acute effects of hepatic ACSL4 deficiency on lipid metabolism in adult mice fed a high-fat diet (HFD). Adenovirus-mediated expression of a mouse ACSL4 shRNA (Ad-shAcsl4) in the liver of HFD-fed mice led to a 43% reduction of hepatic arachidonoyl-CoA synthetase activity and a 53% decrease in ACSL4 protein levels compared with mice receiving control adenovirus (Ad-shLacZ). Attenuated ACSL4 expression resulted in a substantial decrease in circulating VLDL-TG levels without affecting plasma cholesterol. Lipidomics profiling revealed that knocking down ACSL4 altered liver PL compositions, with the greatest impact on accumulation of abundant LPC species (LPC 16:0 and LPC 18:0) and lysophosphatidylethanolamine (LPE) species (LPE 16:0 and LPE 18:0). In addition, fasting glucose and insulin levels were higher in Ad-shAcsl4-transduced mice versus control (Ad-shLacZ). Glucose tolerance testing further indicated an insulin-resistant phenotype upon knockdown of ACSL4. These results provide the first in vivo evidence that ACSL4 plays a role in plasma TG and glucose metabolism and hepatic PL synthesis of hyperlipidemic mice.
Collapse
Affiliation(s)
- Amar B Singh
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| | - Chin Fung K Kan
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
- Ochsner Clinical School, University of Queensland School of Medicine , New Orleans, Louisiana
| | - Fredric B Kraemer
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
- Department of Medicine, Stanford University School of Medicine , Stanford, California
- Stanford Diabetes Research Center, Stanford University School of Medicine , Stanford, California
| | - Raymond A Sobel
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
- Department of Pathology, Stanford University School of Medicine , Stanford, California
| | - Jingwen Liu
- Veterans Affairs Palo Alto Health Care System, Palo Alto, California
| |
Collapse
|
6
|
Sanghera DK, Bejar C, Sharma S, Gupta R, Blackett PR. Obesity genetics and cardiometabolic health: Potential for risk prediction. Diabetes Obes Metab 2019; 21:1088-1100. [PMID: 30667137 PMCID: PMC6530772 DOI: 10.1111/dom.13641] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/17/2019] [Accepted: 01/19/2019] [Indexed: 02/06/2023]
Abstract
The increasing burden of obesity worldwide and its effect on cardiovascular disease (CVD) risk is an opportunity for evaluation of preventive approaches. Both obesity and CVD have a genetic background and polymorphisms within genes which enhance expression of variant proteins that influence CVD in obesity. Genome-based prediction may therefore be a feasible strategy, but the identification of genetically driven risk factors for CVD manifesting as clinically recognized phenotypes is a major challenge. Clusters of such risk factors include hyperglycaemia, hypertension, ectopic liver fat, and inflammation. All involve multiple genetic pathways having complex interactions with variable environmental influences. The factors that make significant contributions to CVD risk include altered carbohydrate homeostasis, ectopic deposition of fat in muscle and liver, and inflammation, with contributions from the gut microbiome. A futuristic model depends on harnessing the predictive power of plausible genetic variants, phenotype reversibility, and effective therapeutic choices based on genotype-phenotype interactions. Inverting disease phenotypes into ideal cardiovascular health metrics could improve genetic and epigenetic assessment, and form the basis of a future model for risk detection and early intervention.
Collapse
Affiliation(s)
- Dharambir K. Sanghera
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- (Corresponding authors) Dharambir K. Sanghera, Ph.D., F.A.H.A., Department of Pediatrics, Section of Genetics, University of Oklahoma Health Sciences Center, 940 Stanton L. Young Blvd., Rm. D317 BMSB, Oklahoma City, OK 73104, USA, , Piers R. Blackett, M.D., Department of Pediatrics, Section of Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA,
| | - Cynthia Bejar
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Sonali Sharma
- Department of Biochemistry, College of Medical Sciences, Rajasthan University of Health Sciences, Kumbha Marg, Pratap Nagar, Jaipur 302033, India
| | - Rajeev Gupta
- Academic Research Development Unit, College of Medical Sciences, Rajasthan University of Health Sciences, Kumbha Marg, Pratap Nagar, Jaipur 302033, India
| | - Piers R. Blackett
- Department of Pediatrics, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- (Corresponding authors) Dharambir K. Sanghera, Ph.D., F.A.H.A., Department of Pediatrics, Section of Genetics, University of Oklahoma Health Sciences Center, 940 Stanton L. Young Blvd., Rm. D317 BMSB, Oklahoma City, OK 73104, USA, , Piers R. Blackett, M.D., Department of Pediatrics, Section of Endocrinology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA,
| |
Collapse
|
7
|
Ahmad A, Ali T, Kim MW, Khan A, Jo MH, Rehman SU, Khan MS, Abid NB, Khan M, Ullah R, Jo MG, Kim MO. Adiponectin homolog novel osmotin protects obesity/diabetes-induced NAFLD by upregulating AdipoRs/PPARα signaling in ob/ob and db/db transgenic mouse models. Metabolism 2019; 90:31-43. [PMID: 30473057 DOI: 10.1016/j.metabol.2018.10.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 10/05/2018] [Accepted: 10/15/2018] [Indexed: 12/23/2022]
Abstract
BACKGROUND In metabolic disorders, adiponectin and adiponectin receptors (AdipoR1/R2) signaling has a key role in improving nonalcoholic fatty liver disease (NAFLD) in obesity-associated diabetes. OBJECTIVE To the best of our knowledge, here, we reported for the first time the underlying mechanistic therapeutic efficacy of the novel osmotin, a homolog of mammalian adiponectin, against NAFLD in leptin-deficient ob/ob and db/db mice. METHODS The ob/ob and db/db mice were treated with osmotin at a dose of 5 μg/g three times a week for two weeks. To co-relate the in vivo results we used the human liver carcinoma HepG2 cells, subjected to knockdown with small siRNAs of AdipoR1/R2 and PPARα genes and treated with osmotin and palmitic acid (P.A.). MTT assay, Western blotting, immunohistofluorescence assays, and plasma biochemical analyses were applied. RESULTS Osmotin stimulated AdipoR1/R2 and its downstream APPL1/PPAR-α/AMPK/SIRT1 pathways in ob/ob and db/db mice, and HepG2 cells exposed to P.A. Mechanistically, we confirmed that knockdown of AdipoR1/R2 and PPARα by their respective siRNAs abolished the osmotin activity in HepG2 cells exposed to P.A. Overall, the in vivo and in vitro results suggested that osmotin protected against NAFLD through activation of AdipoR1/R2 and its downstream APPL1/PPAR-α/AMPK/SIRT1 pathways as shown by the reduced body weight, blood glucose level and glycated hemoglobin, improved glucose tolerance, attenuated insulin resistance and hepatic glucogenesis, regulated serum lipid parameters, and increased fatty acid oxidation and mitochondrial functions. CONCLUSION Our findings strongly suggest that novel osmotin might be a potential novel therapeutic tool against obesity/diabetes-induced NAFLD and other metabolic disorders.
Collapse
MESH Headings
- Adiponectin/analogs & derivatives
- Adiponectin/chemistry
- Animals
- Anti-Obesity Agents/pharmacology
- Cytoprotection/drug effects
- Diabetes Mellitus, Experimental/complications
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/pathology
- Disease Models, Animal
- Hep G2 Cells
- Humans
- Hypoglycemic Agents/pharmacology
- Leptin/deficiency
- Leptin/genetics
- Lipid Metabolism/drug effects
- Liver/drug effects
- Liver/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Obese
- Mice, Transgenic
- Non-alcoholic Fatty Liver Disease/etiology
- Non-alcoholic Fatty Liver Disease/pathology
- Non-alcoholic Fatty Liver Disease/prevention & control
- Obesity/complications
- Obesity/genetics
- Obesity/pathology
- PPAR alpha/metabolism
- Plant Proteins/pharmacology
- Receptors, Adiponectin/metabolism
- Receptors, Leptin/deficiency
- Receptors, Leptin/genetics
- Signal Transduction/drug effects
- Up-Regulation/drug effects
Collapse
Affiliation(s)
- Ashfaq Ahmad
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Tahir Ali
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Min Woo Kim
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Amjad Khan
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Myeung Hoon Jo
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Shafiq Ur Rehman
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Muhammad Sohail Khan
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Noman Bin Abid
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Mehtab Khan
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Rahat Ullah
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Min Gi Jo
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea
| | - Myeong Ok Kim
- Division of Applied Life Science (BK 21), College of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea.
| |
Collapse
|
8
|
Vurgun E, Diker İY, Çoban N, Geyik F, Güven G, Erginel Ünaltuna N. ACSL4 gen polimorfizminin (rs7886473) metabolik sendrom ve lipid düzeyleri üzerine etkisi. CUKUROVA MEDICAL JOURNAL 2018. [DOI: 10.17826/cumj.407589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
9
|
Kovalic AJ, Banerjee P, Tran QT, Singal AK, Satapathy SK. Genetic and Epigenetic Culprits in the Pathogenesis of Nonalcoholic Fatty Liver Disease. J Clin Exp Hepatol 2018; 8:390-402. [PMID: 30564000 PMCID: PMC6286466 DOI: 10.1016/j.jceh.2018.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 04/18/2018] [Indexed: 02/08/2023] Open
Abstract
Nonalcoholic Fatty Liver Disease (NAFLD) constitutes a wide spectrum of liver pathology with hepatic steatosis at the core of this pathogenesis. Variations of certain genetic components have demonstrated increased susceptibility for hepatic steatosis. Therefore, these inciting variants must be further characterized in order to ultimately provide effective, targeted therapies for NAFLD and will be the focus of this review. Several genetic variants revealed an association with NAFLD through Genome-wide Association Study, meta-analyses, and retrospective case-control studies. PNPLA3 rs738409 and TM6SF2 rs58542926 are the two genetic variants providing the strongest evidence for association with NAFLD. However, it remains to be determined if these genetic variants serve as the primary culprit which induces the pathogenesis of NAFLD. Prospective and intervention studies are urgently needed to firmly establish a cause-and-effect relationship between the presence of certain genetic variants and risk of NAFLD development and progression.
Collapse
Key Words
- 1H-MRS, Proton Magnetic Resonance Spectroscopy
- ACC2, Acetyl-CoA Carboxylase 2
- ACLY, ATP Citrate Lyase
- BMI, Body Mass Index
- CK-18, Cytokeratin 18
- CT, Computed Tomography
- FASN, Fatty Acid Synthase
- GWAS, Genome-wide Association Study
- HCC, Hepatocellular Carcinoma
- LT, Liver Transplantation
- NAFLD, Nonalcoholic Fatty Liver Disease
- NASH, Nonalcoholic Steatohepatitis
- SCD1, Stearoyl-CoA Desaturase 1
- SNP, Single Nucleotide Polymorphism
- US, Ultrasonography
- epigenetics
- genetic polymorphisms
- genetic variants
- miRNA, MicroRNA
- nonalcoholic fatty liver disease
- single nucleotide polymorphisms
Collapse
Affiliation(s)
- Alexander J. Kovalic
- Wake Forest Baptist Medical Center, Department of Internal Medicine, Winston-Salem, NC, United States
| | - Pratik Banerjee
- University of Memphis, School of Public Health, Division of Epidemiology, Biostatistics, and Environmental Health, Memphis, TN, United States
| | - Quynh T. Tran
- University of Tennessee Health Science Center, Department of Preventive Medicine, Memphis, TN, United States
| | - Ashwani K. Singal
- University of Alabama at Birmingham, Department of Medicine, Division of Gastroenterology and Hepatology, Birmingham, AL, United States
| | - Sanjaya K. Satapathy
- University of Tennessee Health Science Center, Methodist University Hospital Transplant Institute, Memphis, TN, United States
| |
Collapse
|
10
|
Kobayashi H, Otsuka H, Yanai M, Hara M, Hishiki M, Soma M, Abe M. Adiponectin Receptor gene Polymorphisms are Associated with Kidney Function in Elderly Japanese Populations. J Atheroscler Thromb 2018; 26:328-339. [PMID: 30135333 PMCID: PMC6456456 DOI: 10.5551/jat.45609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Aim: Adiponectin exhibits its biological effects through adiponectin receptors (AdipoR1 and AdipoR2), which are distributed in the kidneys, and activation of those receptors could prevent or ameliorate diabetic nephropathy. This study aimed to evaluate the associations between AdipoR single nucleotide polymorphisms (SNPs) and kidney function in an elderly Japanese population. Methods: A total of 271 elderly Japanese volunteers underwent anthropometric and laboratory tests (cystatin C-based eGFR and total and high molecular weight adiponectin levels at baseline and a follow-up visit). Genotype data were obtained for the selected 7 and 5 AdipoR1 and AdipoR2 SNPs, respectively. Results: In a cross-sectional analysis at baseline, we found a significant association between the AdipoR2 SNP rs12230440 and kidney function; eGFRcys tended to increase as the number of carriers of T alleles increased after adjustment for covariates and Bonferroni correction, although the association of the SNP and annual eGFR decline could not be identified in the longitudinal data. Regarding the variants rs16850797, rs11061925, and rs10773983, each of the allele G, allele C, and allele G showed nominally significant associations with higher eGFRcys. However, this failed to reach significance after Bonferroni correction. Conclusion: Here, an AdipoR2 SNP was associated with kidney function, suggesting that the effects of this polymorphism on adiponectin receptor may affect kidney function in the elderly Japanese population.
Collapse
Affiliation(s)
- Hiroki Kobayashi
- Division of Nephrology, Hypertension and Endocrinology, Department of Internal Medicine, Nihon University School of Medicine
| | - Hiromasa Otsuka
- Division of General Medicine, Department of Internal Medicine, Nihon University School of Medicine
| | - Mitsuru Yanai
- Division of General Medicine, Department of Internal Medicine, Nihon University School of Medicine
| | - Motohiko Hara
- Department of Nursing, School of Health and Social Services, Saitama Prefectural University
| | - Mikano Hishiki
- Department of Diabetes and Endocrinology, Tokyo Metropolitan Hiroo Hospital
| | - Masayoshi Soma
- Division of General Medicine, Department of Internal Medicine, Nihon University School of Medicine
| | - Masanori Abe
- Division of Nephrology, Hypertension and Endocrinology, Department of Internal Medicine, Nihon University School of Medicine
| |
Collapse
|
11
|
Mora-García G, Ruiz-Díaz MS, Espitia-Almeida F, Gómez-Camargo D. Variations in ADIPOR1 But Not ADIPOR2 are Associated With Hypertriglyceridemia and Diabetes in an Admixed Latin American Population. Rev Diabet Stud 2017; 14:311-328. [PMID: 29145541 PMCID: PMC6115010 DOI: 10.1900/rds.2017.14.311] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/17/2017] [Accepted: 08/29/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Adiponectin is a hormone secreted by adipose tissue. It regulates glycolysis and lipolysis and is involved in the pathophysiology of diabetes and related disorders. Its activity is mainly mediated by the transmembrane receptors AdipoR1 and AdipoR2, which are encoded by ADIPOR1 (1q32.1) and ADIPOR2 (12p13.33) genes, respectively. In genetic association studies, single nucleotide polymorphisms (SNPs) in or near these genes have been associated with metabolic alterations. However, these relationships are still controversial. AIM The aim of this work was to analyze possible associations between ADIPOR1/2 and diabetes and other metabolic disorders. METHODS A genetic association study was carried out in an admixed Latin American population. A sample of 200 adults was analyzed. Clinical and serum-biochemical characteristics were measured to diagnose obesity, abdominal obesity, hypertension, hyperglycemia, hypertriglyceridemia, low HDLc, insulin resistance (HOMA-IR), and diabetes. Three SNPs were genotyped in ADIPOR1 (rs10494839, rs12733285, and rs2275737) and ADIPOR2 (rs11061937, rs11612383, and rs2286383). For the association analysis, an additive model was assessed through logistic regression. An admixture adjustment was performed using a Monte-Carlo-Markov-Chain method, assuming a three-hybrid substructure (k = 3). RESULTS Two SNPs in ADIPOR1 were associated with diabetes: rs10494839 (OR = 3.88, adjusted p < 0.03) and rs12733285 (OR = 4.72, adjusted p < 0.03). Additionally, rs10494839 was associated with hypertriglyceridemia (OR = 2.16, adjusted p < 0.01). None of the SNPs in ADIPOR2 were associated with metabolic disorders. CONCLUSIONS ADIPOR1 was consistently associated with diabetes and hypertriglyceridemia. This association was maintained even after adjusting for genetic stratification. There were no significant associations involving ADIPOR2.
Collapse
Affiliation(s)
- Gustavo Mora-García
- Doctorate in Tropical Medicine, Faculty of Medicine, Universidad de Cartagena. Cartagena de Indias, Colombia
| | - María S. Ruiz-Díaz
- Doctorate in Tropical Medicine, Faculty of Medicine, Universidad de Cartagena. Cartagena de Indias, Colombia
| | - Fabian Espitia-Almeida
- Biochemistry Master Program, Faculty of Medicine, Universidad de Cartagena. Cartagena de Indias, Colombia
| | - Doris Gómez-Camargo
- Doctorate in Tropical Medicine, Faculty of Medicine, Universidad de Cartagena. Cartagena de Indias, Colombia
| |
Collapse
|
12
|
Zhang DM, Jiao RQ, Kong LD. High Dietary Fructose: Direct or Indirect Dangerous Factors Disturbing Tissue and Organ Functions. Nutrients 2017; 9:E335. [PMID: 28353649 PMCID: PMC5409674 DOI: 10.3390/nu9040335] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/15/2017] [Accepted: 03/24/2017] [Indexed: 02/06/2023] Open
Abstract
High dietary fructose is a major contributor to insulin resistance and metabolic syndrome, disturbing tissue and organ functions. Fructose is mainly absorbed into systemic circulation by glucose transporter 2 (GLUT2) and GLUT5, and metabolized in liver to produce glucose, lactate, triglyceride (TG), free fatty acid (FFA), uric acid (UA) and methylglyoxal (MG). Its extrahepatic absorption and metabolism also take place. High levels of these metabolites are the direct dangerous factors. During fructose metabolism, ATP depletion occurs and induces oxidative stress and inflammatory response, disturbing functions of local tissues and organs to overproduce inflammatory cytokine, adiponectin, leptin and endotoxin, which act as indirect dangerous factors. Fructose and its metabolites directly and/or indirectly cause oxidative stress, chronic inflammation, endothelial dysfunction, autophagy and increased intestinal permeability, and then further aggravate the metabolic syndrome with tissue and organ dysfunctions. Therefore, this review addresses fructose-induced metabolic syndrome, and the disturbance effects of direct and/or indirect dangerous factors on the functions of liver, adipose, pancreas islet, skeletal muscle, kidney, heart, brain and small intestine. It is important to find the potential correlations between direct and/or indirect risk factors and healthy problems under excess dietary fructose consumption.
Collapse
Affiliation(s)
- Dong-Mei Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210023, China.
| | - Rui-Qing Jiao
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210023, China.
| | - Ling-Dong Kong
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210023, China.
| |
Collapse
|
13
|
Holland WL, Xia JY, Johnson JA, Sun K, Pearson MJ, Sharma AX, Quittner-Strom E, Tippetts TS, Gordillo R, Scherer PE. Inducible overexpression of adiponectin receptors highlight the roles of adiponectin-induced ceramidase signaling in lipid and glucose homeostasis. Mol Metab 2017; 6:267-275. [PMID: 28271033 PMCID: PMC5323887 DOI: 10.1016/j.molmet.2017.01.002] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 12/27/2016] [Accepted: 01/05/2017] [Indexed: 02/06/2023] Open
Abstract
Objective Adiponectin and the signaling induced by its cognate receptors, AdipoR1 and AdipoR2, have garnered attention for their ability to promote insulin sensitivity and oppose steatosis. Activation of these receptors promotes the deacylation of ceramide, a lipid metabolite that appears to play a causal role in impairing insulin signaling. Methods Here, we have developed transgenic mice that overexpress AdipoR1 or AdipoR2 under the inducible control of a tetracycline response element. These represent the first inducible genetic models that acutely manipulate adiponectin receptor signaling in adult mouse tissues, which allows us to directly assess AdipoR signaling on glucose and lipid metabolism. Results Overexpression of either adiponectin receptor isoform in the adipocyte or hepatocyte is sufficient to enhance ceramidase activity, whole body glucose metabolism, and hepatic insulin sensitivity, while opposing hepatic steatosis. Importantly, metabolic improvements fail to occur in an adiponectin knockout background. When challenged with a leptin-deficient genetic model of type 2 diabetes, AdipoR2 expression in adipose or liver is sufficient to reverse hyperglycemia and glucose intolerance. Conclusion These observations reveal that adiponectin is critical for AdipoR-induced ceramidase activation which enhances hepatic glucose and lipid metabolism via rapidly acting “cross-talk” between liver and adipose tissue sphingolipids. Adiponectin receptor signaling in adipose prompts beneficial effects on whole-body glucose and lipid metabolism. The small molecule adiponectin receptor antagonist AdipoRon lowers hepatic ceramides. Depletion of ceramides in adipocytes results in diminished hepatic ceramide accumulation. Depletion of ceramides in hepatocytes results in diminished adipose sphingolipid accumulation. Adiponectin is essential for the beneficial effects of adiponectin receptors on glucose, ceramide, and lipid metabolism.
Collapse
Affiliation(s)
- William L Holland
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA.
| | - Jonathan Y Xia
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Joshua A Johnson
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Kai Sun
- Center for Metabolic and Degenerative Diseases, Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Mackenzie J Pearson
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Ankit X Sharma
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Ezekiel Quittner-Strom
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Trevor S Tippetts
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Ruth Gordillo
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA; Department of Cell Biology, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| |
Collapse
|
14
|
Panera N, Della Corte C, Crudele A, Stronati L, Nobili V, Alisi A. Recent advances in understanding the role of adipocytokines during non-alcoholic fatty liver disease pathogenesis and their link with hepatokines. Expert Rev Gastroenterol Hepatol 2016; 10:393-403. [PMID: 26654761 DOI: 10.1586/17474124.2016.1110485] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is currently considered the main cause of chronic liver disease worldwide. Mechanisms leading to the development and progression of this disease are topics of great interest for researchers and clinicians. The current multi-hit hypothesis has thrown the crosstalk between liver and adipose tissue into sharp focus. It is well known that adipose tissue produces circulating factors, known as adipocytokines, which exert several effects on liver cells, promoting the onset of NAFLD and its progression to non-alcoholic steatohepatitis in obese subjects. In a similar way, hepatocytes may also respond to obesogenic stimuli by producing and releasing hepatokines into the circulation. Here, the authors provide an overview of recent advances in our understanding of the role of the most relevant adipocytokines and hepatokines in NAFLD pathogenesis, highlighting their possible molecular and functional interactions.
Collapse
Affiliation(s)
- Nadia Panera
- a Liver Research Unit , 'Bambino Gesù' Children's Hospital, IRCCS , Rome , Italy
| | - Claudia Della Corte
- b Hepato-Metabolic Disease Unit , 'Bambino Gesù' Children's Hospital, IRCCS , Rome , Italy
| | - Annalisa Crudele
- a Liver Research Unit , 'Bambino Gesù' Children's Hospital, IRCCS , Rome , Italy
| | - Laura Stronati
- c Department of Radiobiology and Human Health , ENEA , Rome , Italy
| | - Valerio Nobili
- b Hepato-Metabolic Disease Unit , 'Bambino Gesù' Children's Hospital, IRCCS , Rome , Italy
| | - Anna Alisi
- a Liver Research Unit , 'Bambino Gesù' Children's Hospital, IRCCS , Rome , Italy
| |
Collapse
|
15
|
Genomics of human fatty liver disease reveal mechanistically linked lipid droplet-associated gene regulations in bland steatosis and nonalcoholic steatohepatitis. Transl Res 2016; 177:41-69. [PMID: 27376874 DOI: 10.1016/j.trsl.2016.06.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 05/13/2016] [Accepted: 06/08/2016] [Indexed: 12/11/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common disorder hallmarked by excessive lipid deposits. Based on our recent research on lipid droplet (LD) formation in hepatocytes, we investigated LD-associated gene regulations in NAFLD of different grades, that is, steatosis vs steatohepatitis by comparing liver biopsies from healthy controls (N = 13) and NAFLD patients (N = 102). On average, more than 700 differentially expressed genes (DEGs) were identified of which 146 are mechanistically linked to LD formation. We identified 51 LD-associated DEGs frequently regulated in patient samples (range ≥5 to ≤102) with the liver-receptor homolog-1(NR5A2), that is, a key regulator of cholesterol metabolism being commonly repressed among 100 patients examined. With bland steatosis, notable regulations involved hypoxia-inducible lipid droplet-associated-protein and diacylglycerol-O-acyltransferase-2 renowned for their role in LD-growth. Conversely, nonalcoholic steatohepatitis-associated DEGs coded for epidermal growth factor receptor and TLR4 signaling with decreased expression of the GTPase Rab5 and the lipid phosphohydrolase PPAP2B thus highlighting adaptive responses to inflammation, LDL-mediated endocytosis and lipogenesis, respectively. Studies with steatotic primary human hepatocyte cultures demonstrated induction of LD-associated PLIN2, CIDEC, DNAAF1, whereas repressed expression of CPT1A, ANGPTL4, and PKLR informed on burdened mitochondrial metabolism. Equally, repressed expression of the B-lymphocyte chemoattractant CXCL13 and STAT4 as well as induced FGF21 evidenced amelioration of steatosis-related inflammation. In-vitro/in-vivo patient sample comparisons confirmed C-reactive protein, SOCS3, NR5A2, and SOD2 as commonly regulated. Lastly, STRING network analysis highlighted potential "druggable" targets with PLIN2, CIDEC, and hypoxia-inducible lipid droplet-associated-protein being confirmed by immunofluorescence microscopy. In conclusion, steatosis and steatohepatitis specific gene regulations informed on the pathogenesis of NAFLD to broaden the perspective of targeted therapies.
Collapse
|
16
|
Yang G, Liu N, Hu M, Xin X, Han J, Cai Y, Hu Z, Jia C, Zhang M. A Variant in ADIPOR2 Is Associated with Increased Free Fatty Acid Levels in Chinese Population. Metab Syndr Relat Disord 2016; 14:368-71. [PMID: 27348122 DOI: 10.1089/met.2016.0005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
BACKGROUND Elevated free fatty acids (FFAs) are thought to play an important role in the development of insulin resistance. Adiponectin is an adipose tissue-secreted protein known for its effects on the stimulation of fatty acid oxidation. The aim of this study was to investigate the association of adiponectin receptor 2 gene variations with FFAs levels in subjects with normal fasting glucose levels in Chinese Han population. METHODS Four common single nucleotide polymorphisms of ADIPOR2 were genotyped using the TaqMan method to perform association studies with metabolic parameters in 1819 subjects among Chinese Han population. All the subjects were divided into two groups: normal FFAs group (FFAs ≤0.88 mmol/L) and high FFAs group (FFAs >0.88 mmol/L). RESULTS There was a significant association of rs2370055 with higher FFA levels in major T-allele carriers (P = 0.000). There was a significant difference in the distribution of genotypes of polymorphism rs2370055 between normal and high FFA groups. The frequencies of TT and CT genotypes are significantly higher in subjects with high FFA level than those in the normal FFAs group (P = 0.013 and P = 0.004, respectively). After adjustment for age, sex, body mass index, triglyceride, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoproteincholesterol, the TT and CT genotypes are both independent risk factors for high FFAs level. CONCLUSIONS Our findings suggest that variants of ADIPOR2 could be a determinant for higher FFA levels, and among Chinese Han population, carriers of the CT and TT genotypes for rs2370055 even with normal glucose levels may have significantly higher insulin resistance susceptibility.
Collapse
Affiliation(s)
- Guihua Yang
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Na Liu
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Mei Hu
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Xuli Xin
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Jing Han
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Yuyu Cai
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Zhiying Hu
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Chundi Jia
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| | - Man Zhang
- 1 Department of Clinical Laboratory Medicine, Beijing Shijitan Hospital, Peking University Ninth School of Clinical Medicine , Beijing, China .,2 Beijing Shijitan Hospital, Capital Medical University , Beijing, China
| |
Collapse
|
17
|
Ramos-Lopez O, Martinez-Lopez E, Roman S, Fierro NA, Panduro A. Genetic, metabolic and environmental factors involved in the development of liver cirrhosis in Mexico. World J Gastroenterol 2015; 21:11552-11566. [PMID: 26556986 PMCID: PMC4631960 DOI: 10.3748/wjg.v21.i41.11552] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 07/29/2015] [Accepted: 09/14/2015] [Indexed: 02/06/2023] Open
Abstract
Liver cirrhosis (LC) is a chronic illness caused by inflammatory responses and progressive fibrosis. Globally, the most common causes of chronic liver disease include persistent alcohol abuse, followed by viral hepatitis infections and nonalcoholic fatty liver disease. However, regardless of the etiological factors, the susceptibility and degree of liver damage may be influenced by genetic polymorphisms that are associated with distinct ethnic and cultural backgrounds. Consequently, metabolic genes are influenced by variable environmental lifestyle factors, such as diet, physical inactivity, and emotional stress, which are associated with regional differences among populations. This Topic Highlight will focus on the genetic and environmental factors that may influence the metabolism of alcohol and nutrients in the setting of distinct etiologies of liver disease. The interaction between genes and environment in the current-day admixed population, Mestizo and Native Mexican, will be described. Additionally, genes involved in immune regulation, insulin sensitivity, oxidative stress and extracellular matrix deposition may modulate the degree of severity. In conclusion, LC is a complex disease. The onset, progression, and clinical outcome of LC among the Mexican population are influenced by specific genetic and environmental factors. Among these are an admixed genome with a heterogenic distribution of European, Amerindian and African ancestry; a high score of alcohol consumption; viral infections; a hepatopathogenic diet; and a high prevalence of obesity. The variance in risk factors among populations suggests that intervention strategies directed towards the prevention and management of LC should be tailored according to such population-based features.
Collapse
|
18
|
Zhou YJ, Zhang ZS, Nie YQ, Cao J, Cao CY, Li YY. Association of adiponectin gene variation with progression of nonalcoholic fatty liver disease: A 4-year follow-up survey. J Dig Dis 2015; 16:601-9. [PMID: 26334200 DOI: 10.1111/1751-2980.12288] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/17/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To explore the role of tagging single nucleotide polymorphisms (tagSNPs) in the adiponectin gene in the natural course of nonalcoholic fatty liver disease (NAFLD). METHODS The participants were chosen from our previous survey containing 3543 individuals. Finally, a total of 696 participants who had been followed up for a median of 4 years were included. Each participant was administered with an interview, physical examination, blood tests and ultrasonic examination at both baseline and end-point. Polymerase chain reaction-restriction fragment length polymorphism was applied to determine seven tagSNPs in the adiponectin gene, namely, rs182052, rs16861205, rs822396, rs7627128, rs1501299, rs2241767 and rs3774261. Ordinal logistic regression was used to screen risk factors of NAFLD progression as well as the susceptibility to the disease. Haplotypes analyses were performed to confirm the results. RESULTS After adjusting for age and gender, rs1501299 (G276T), rs2241767 (A45G) and rs3774261 (A712G) were found to be risk factors of both susceptibility (OR 5.040, 7.471 and 3.546, respectively) and progression (OR 3.83, 3.51 and 3.30, respectively) to NAFLD. Nevertheless, rs182052, rs16861205, rs822396 and rs7627128 had no impact on them. These findings were confirmed by haplotype analysis. CONCLUSION The tagSNPs rs2241767, rs1501299 and rs3774261 in the adiponectin gene are risk factors for the individuals' susceptibility to and progression of NAFLD.
Collapse
Affiliation(s)
- Yong Jian Zhou
- Department of Gastroenterology and Hepatology, Guangzhou Digestive Diseases Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangdong, China
| | - Zong Sheng Zhang
- Department of Gastroenterology and Hepatology, Guangzhou Digestive Diseases Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangdong, China
| | - Yu Qiang Nie
- Department of Gastroenterology and Hepatology, Guangzhou Digestive Diseases Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangdong, China
| | - Jie Cao
- Department of Gastroenterology and Hepatology, Guangzhou Digestive Diseases Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangdong, China
| | - Chuang Yu Cao
- Department of Gastroenterology and Hepatology, Guangzhou Digestive Diseases Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangdong, China
| | - Yu Yuan Li
- Department of Gastroenterology and Hepatology, Guangzhou Digestive Diseases Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangdong, China
| |
Collapse
|
19
|
Johns N, Tan BH, MacMillan M, Solheim TS, Ross JA, Baracos VE, Damaraju S, Fearon KCH. Genetic basis of interindividual susceptibility to cancer cachexia: selection of potential candidate gene polymorphisms for association studies. J Genet 2015; 93:893-916. [PMID: 25572253 DOI: 10.1007/s12041-014-0405-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cancer cachexia is a complex and multifactorial disease. Evolving definitions highlight the fact that a diverse range of biological processes contribute to cancer cachexia. Part of the variation in who will and who will not develop cancer cachexia may be genetically determined. As new definitions, classifications and biological targets continue to evolve, there is a need for reappraisal of the literature for future candidate association studies. This review summarizes genes identified or implicated as well as putative candidate genes contributing to cachexia, identified through diverse technology platforms and model systems to further guide association studies. A systematic search covering 1986-2012 was performed for potential candidate genes / genetic polymorphisms relating to cancer cachexia. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Pathway analysis software was used to reveal possible network associations between genes. Functionality of SNPs/genes was explored based on published literature, algorithms for detecting putative deleterious SNPs and interrogating the database for expression of quantitative trait loci (eQTLs). A total of 154 genes associated with cancer cachexia were identified and explored for functional polymorphisms. Of these 154 genes, 119 had a combined total of 281 polymorphisms with functional and/or clinical significance in terms of cachexia associated with them. Of these, 80 polymorphisms (in 51 genes) were replicated in more than one study with 24 polymorphisms found to influence two or more hallmarks of cachexia (i.e., inflammation, loss of fat mass and/or lean mass and reduced survival). Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides a contemporary basis to select genes and/or polymorphisms for further association studies in cancer cachexia, and to develop their potential as susceptibility biomarkers of cachexia.
Collapse
Affiliation(s)
- N Johns
- Department of Clinical and Surgical Sciences, University of Edinburgh, Edinburgh, EH16 4SB, UK.
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Edelman D, Kalia H, Delio M, Alani M, Krishnamurthy K, Abd M, Auton A, Wang T, Wolkoff AW, Morrow BE. Genetic analysis of nonalcoholic fatty liver disease within a Caribbean-Hispanic population. Mol Genet Genomic Med 2015; 3:558-69. [PMID: 26740948 PMCID: PMC4694126 DOI: 10.1002/mgg3.168] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/07/2015] [Accepted: 07/09/2015] [Indexed: 12/18/2022] Open
Abstract
We explored potential genetic risk factors implicated in nonalcoholic fatty liver disease (NAFLD) within a Caribbean–Hispanic population in New York City. A total of 316 individuals including 40 subjects with biopsy‐proven NAFLD, 24 ethnically matched non‐NAFLD controls, and a 252 ethnically mixed random sampling of Bronx County, New York were analyzed. Genotype analysis was performed to determine allelic frequencies of 74 known single‐nucleotide polymorphisms (SNPs) associated with NAFLD risk based on previous genome‐wide association study (GWAS) and candidate gene studies. Additionally, the entire coding region of PNPLA3, a gene showing the strongest association to NAFLD was subjected to Sanger sequencing. Results suggest that both rare and common DNA variations in PNPLA3 and SAMM50 may be correlated with NAFLD in this small population study, while common DNA variations in CHUK and ERLIN1, may have a protective interaction. Common SNPs in ENPP1 and ABCC2 have suggestive association with fatty liver, but with less compelling significance. In conclusion, Hispanic patients of Caribbean ancestry may have different interactions with NAFLD genetic modifiers; therefore, further investigation with a larger sample size, into this Caribbean–Hispanic population is warranted.
Collapse
Affiliation(s)
- Deborah Edelman
- Department of GeneticsAlbert Einstein College of Medicine1301 Morris Park Ave.BronxNew York10461
| | - Harmit Kalia
- Division of Gastroenterology and Liver DiseasesMontefiore Medical Center and Albert Einstein College of MedicineBronxNew York10461
| | - Maria Delio
- Department of GeneticsAlbert Einstein College of Medicine1301 Morris Park Ave.BronxNew York10461
- Marion Bessin Liver Research CenterAlbert Einstein College of MedicineBronxNew York10461
| | - Mustafa Alani
- Division of Gastroenterology and Liver DiseasesMontefiore Medical Center and Albert Einstein College of MedicineBronxNew York10461
| | - Karthik Krishnamurthy
- Division of Gastroenterology and Liver DiseasesMontefiore Medical Center and Albert Einstein College of MedicineBronxNew York10461
| | - Mortadha Abd
- Division of Gastroenterology and Liver DiseasesMontefiore Medical Center and Albert Einstein College of MedicineBronxNew York10461
| | - Adam Auton
- Department of GeneticsAlbert Einstein College of Medicine1301 Morris Park Ave.BronxNew York10461
| | - Tao Wang
- Department of Epidemiology & Population HealthAlbert Einstein College of MedicineBronxNew York10461
| | - Allan W. Wolkoff
- Division of Gastroenterology and Liver DiseasesMontefiore Medical Center and Albert Einstein College of MedicineBronxNew York10461
- Marion Bessin Liver Research CenterAlbert Einstein College of MedicineBronxNew York10461
- Department of Anatomy and Structural BiologyAlbert Einstein College of MedicineBronxNew York10461
| | - Bernice E. Morrow
- Department of GeneticsAlbert Einstein College of Medicine1301 Morris Park Ave.BronxNew York10461
- Department of Anatomy and Structural BiologyAlbert Einstein College of MedicineBronxNew York10461
| |
Collapse
|
21
|
Kasturiratne A, Akiyama K, Niriella MA, Takeuchi F, Isono M, Dassanayake AS, de Silva AP, Wickremasinghe RA, Kato N, de Silva HJ. Association of genetic variants with non-alcoholic fatty liver disease in an urban Sri Lankan community. Liver Int 2015; 35:676-9. [PMID: 24947803 DOI: 10.1111/liv.12624] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 06/15/2014] [Indexed: 12/18/2022]
|
22
|
Kan CFK, Singh AB, Dong B, Shende VR, Liu J. PPARδ activation induces hepatic long-chain acyl-CoA synthetase 4 expression in vivo and in vitro. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:577-87. [PMID: 25645621 DOI: 10.1016/j.bbalip.2015.01.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/07/2015] [Accepted: 01/14/2015] [Indexed: 12/29/2022]
Abstract
The arachidonic acid preferred long-chain acyl-CoA synthetase 4 (ACSL4) is a key enzyme for fatty acid metabolism in various metabolic tissues. In this study, we utilized hamsters fed a normal chow diet, a high-fat diet or a high cholesterol and high fat diet (HCHFD) as animal models to explore novel transcriptional regulatory mechanisms for ACSL4 expression under hyperlipidemic conditions. Through cloning hamster ACSL4 homolog and tissue profiling ACSL4 mRNA and protein expressions we observed a selective upregulation of ACSL4 in testis and liver of HCHFD fed animals. Examination of transcriptional activators of the ACSL family revealed an increased hepatic expression of PPARδ but not PPARα in HCHFD fed hamsters. To explore a role of PPARδ in dietary cholesterol-mediated upregulation of ACSL4, we administered a PPARδ specific agonist L165041 to normolipidemic and dyslipidemic hamsters. We observed significant increases of hepatic ACSL4 mRNA and protein levels in all L165041-treated hamsters as compared to control animals. The induction of ACSL4 expression by L165041 in liver tissue in vivo was recapitulated in human primary hepatocytes and hepatocytes isolated from hamster and mouse. Moreover, employing the approach of adenovirus-mediated gene knockdown, we showed that depletion of PPARδ in hamster hepatocytes specifically reduced ACSL4 expression. Finally, utilizing HepG2 as a model system, we demonstrate that PPARδ activation leads to increased ACSL4 promoter activity, mRNA and protein expression, and consequently higher arachidonoyl-CoA synthetase activity. Taken together, we have discovered a novel PPARδ-mediated regulatory mechanism for ACSL4 expression in liver tissue and cultured hepatic cells.
Collapse
Affiliation(s)
- Chin Fung Kelvin Kan
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, United States
| | - Amar Bahadur Singh
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, United States
| | - Bin Dong
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, United States
| | - Vikram Ravindra Shende
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, United States; Department of Medicine, Stanford University, Stanford, CA 94305, United States
| | - Jingwen Liu
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, United States.
| |
Collapse
|
23
|
Xin XM, Zhong MX, Yang GL, Peng Y, Zhang YL, Zhu W. GW4064, a farnesoid X receptor agonist, upregulates adipokine expression in preadipocytes and HepG2 cells. World J Gastroenterol 2014; 20:15727-15735. [PMID: 25400456 PMCID: PMC4229537 DOI: 10.3748/wjg.v20.i42.15727] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 06/13/2014] [Accepted: 07/11/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effect of GW4064 on the expression of adipokines and their receptors during differentiation of 3T3-L1 preadipocytes and in HepG2 cells.
METHODS: The mRNA expression of farnesoid X receptor (FXR), peroxisome proliferator-activated receptor-gamma 2 (PPAR-γ2), adiponectin, leptin, resistin, adiponectin receptor 1 (AdipoR1), adiponectin receptor 2 (AdipoR2), and the long isoform of leptin receptor (OB-Rb) and protein levels of adiponectin, leptin, and resistin were determined using fluorescent real-time PCR and enzyme linked immunosorbent assay, respectively, on days 0, 2, 4, 6, and 8 during the differentiation of 3T3-L1 preadipocytes exposed to GW4064. Moreover, mRNA expression of AdipoR2 and OB-Rb was also examined using fluorescent real-time PCR at 0, 12, 24, and 48 h in HepG2 cells treated with GW4064.
RESULTS: The mRNA expression of FXR, PPAR-γ2, adiponectin, leptin, resistin, AdipoR1, AdipoR2, and OB-Rb and protein levels of adiponectin, leptin, and resistin increased along with differentiation of 3T3-L1 preadipocytes (P < 0.05 for all). The mRNA expression of FXR, PPAR-γ2, adiponectin, leptin, and AdipoR2 in 3T3-L1 preadipocytes, and AdipoR2 and OB-Rb in HepG2 cells was significantly increased after treatment with GW4064, when compared with the control group (P < 0.05 for all). A similar trend was observed for protein levels of adipokines (including adiponectin, leptin and resistin). However, the expression of resistin, AdipoR1, and OB-Rb in 3T3-L1 cells did not change after treatment with GW4064.
CONCLUSION: The FXR agonist through regulating, at least partially, the expression of adipokines and their receptors could offer an innovative way for counteracting the progress of metabolic diseases such as nonalcoholic fatty liver disease.
Collapse
MESH Headings
- 3T3-L1 Cells
- Adipocytes/drug effects
- Adipocytes/metabolism
- Adipokines/genetics
- Adipokines/metabolism
- Animals
- Hep G2 Cells
- Hepatocytes/drug effects
- Hepatocytes/metabolism
- Humans
- Isoxazoles/pharmacology
- Mice
- PPAR gamma/drug effects
- PPAR gamma/genetics
- PPAR gamma/metabolism
- RNA, Messenger/metabolism
- Receptors, Adiponectin/drug effects
- Receptors, Adiponectin/genetics
- Receptors, Adiponectin/metabolism
- Receptors, Cytoplasmic and Nuclear/agonists
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, Leptin/drug effects
- Receptors, Leptin/genetics
- Receptors, Leptin/metabolism
- Signal Transduction/drug effects
- Time Factors
- Up-Regulation
Collapse
|
24
|
Bag S, Anbarasu A. Revealing the Strong Functional Association of adipor2 and cdh13 with adipoq: A Gene Network Study. Cell Biochem Biophys 2014; 71:1445-56. [DOI: 10.1007/s12013-014-0367-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
25
|
Mazzoccoli G, Vinciguerra M, Oben J, Tarquini R, De Cosmo S. Non-alcoholic fatty liver disease: the role of nuclear receptors and circadian rhythmicity. Liver Int 2014; 34:1133-52. [PMID: 24649929 DOI: 10.1111/liv.12534] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 03/16/2014] [Indexed: 12/22/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the accumulation of triglycerides in the hepatocytes in the absence of excess alcohol intake, and is caused by an imbalance between hepatic synthesis and breakdown of fats, as well as fatty acid storage and disposal. Liver metabolic pathways are driven by circadian biological clocks, and hepatic health is maintained by proper timing of circadian patterns of metabolic gene expression with the alternation of anabolic processes corresponding to feeding/activity during wake times, and catabolic processes characterizing fasting/resting during sleep. A number of nuclear receptors in the liver are expressed rhythmically, bind hormones and metabolites, sense energy flux and expenditure, and connect the metabolic pathways to the molecular clockwork throughout the 24-h day. In this review, we describe the role played by the nuclear receptors in the genesis of NAFLD in relationship with the circadian clock circuitry.
Collapse
Affiliation(s)
- Gianluigi Mazzoccoli
- Division of Internal Medicine and Chronobiology Unit, Department of Medical Sciences, IRCCS Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", San Giovanni Rotondo (FG), Italy
| | | | | | | | | |
Collapse
|
26
|
Wang L, Tian Y, Mei X, Han R, Li G, Kang X. SNPs in the adiponectin receptor 2 gene and their associations with chicken performance traits. Anim Biotechnol 2014; 26:1-7. [PMID: 25153449 DOI: 10.1080/10495398.2013.862254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The adiponectin receptor 2 (ADIPOR2) is a receptor for both globular and full-length adiponectin. In the current study, two genetic variations in ADIPOR2 gene were identified in an F2 resource population of Gushi chicken and Anka broiler. Association analysis between the two SNPs and chicken performance traits were determined using the linear mixed model. The data revealed that the g.34490C > T mutation in intron 3 was significantly associated with liver weight and globulin, the g.35363T > C polymorphism in exon 5 was significantly associated with body weights at 6, 10, and 12 weeks of age. Both polymorphisms have no significant effects on serum glucose and fat-related traits. The g.34490C > T mutation might play an important role in regulating liver weight. The g.35363T > C polymorphism does contribute in a significant manner to growth traits at the medium and later development stage but it is uncertain whether it could be a molecular marker for liver disease.
Collapse
Affiliation(s)
- Lele Wang
- a College of Animal Science and Veterinary Medicine , Henan Agricultural University , Zhengzhou , China
| | | | | | | | | | | |
Collapse
|
27
|
Simó R, Saez-Lopez C, Lecube A, Hernandez C, Fort JM, Selva DM. Adiponectin upregulates SHBG production: molecular mechanisms and potential implications. Endocrinology 2014; 155:2820-30. [PMID: 24828613 DOI: 10.1210/en.2014-1072] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Epidemiological studies have shown that plasma SHBG levels correlate with plasma adiponectin levels, both in men and women. There are no reports describing any molecular mechanism by which adiponectin regulates hepatic SHBG production. The aim of the present study is to explore whether adiponectin regulates SHBG production by increasing HNF-4α levels through reducing hepatic lipid content. For this purpose, in vitro studies using human HepG2 cells, as well as human liver biopsies, were performed. Our results show that adiponectin treatment increased SHBG production via AMPK activation in HepG2 cells. Adiponectin treatment decreased the mRNA and protein levels of enzymes related to hepatic lipogenesis (ACC) and increased those related to fatty acid oxidation (ACOX and CPTI). These adiponectin-induced changes in hepatic enzymes resulted in a reduction of total TG and FFA and an increase of HNF-4α. When HNF-4α expression was silenced by using siRNA, adiponectin-induced SHBG overexpression was blocked. Furthermore, adiponectin-induced upregulation of SHBG production via HNF-4α overexpression was abrogated by the inhibition of fatty acid oxidation or by the induction of lipogenesis with a 30mM glucose treatment in HepG2 cells. Finally, adiponectin levels correlated positively and significantly with both HNF-4α and SHBG mRNA levels in human liver biopsies. Our results suggest for the first time that adiponectin increases SHBG production by activating AMPK, which reduces hepatic lipid content and increases HNF-4α levels.
Collapse
Affiliation(s)
- Rafael Simó
- Diabetes and Metabolism Research Unit (R.S., C.S.-L., C.H., D.M.S.), Vall d'Hebron Institut de Recerca, 08035 Barcelona, Universitat Autónoma de Barcelona, 08193 Barcelona, Centro de Investigación Biomédica en Red, 28029 Madrid, Spain Endocrinology and Nutrition Unit (A.L.), Hospital Universitari Arnau de Vilanova, 25198 Lleida, Spain; Endocrine, Metabolic and Bariatric Unit (J.M.F.), General Surgery Department, Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
| | | | | | | | | | | |
Collapse
|
28
|
Kan CFK, Singh AB, Stafforini DM, Azhar S, Liu J. Arachidonic acid downregulates acyl-CoA synthetase 4 expression by promoting its ubiquitination and proteasomal degradation. J Lipid Res 2014; 55:1657-67. [PMID: 24879802 PMCID: PMC4109760 DOI: 10.1194/jlr.m045971] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Indexed: 01/16/2023] Open
Abstract
ACSL4 is a member of the long-chain acyl-CoA synthetase (ACSL) family with a marked preference for arachidonic acid (AA) as its substrate. Although an association between elevated levels of ACSL4 and hepatosteatosis has been reported, the function of ACSL4 in hepatic FA metabolism and the regulation of its functional expression in the liver remain poorly defined. Here we provide evidence that AA selectively downregulates ACSL4 protein expression in hepatic cells. AA treatment decreased the half-life of ACSL4 protein in HepG2 cells by approximately 4-fold (from 17.3 ± 1.8 h to 4.2 ± 0.4 h) without causing apoptosis. The inhibitory action of AA on ACSL4 protein stability could not be prevented by rosiglitazone or inhibitors that interfere with the cellular pathways involved in AA metabolism to biologically active compounds. In contrast, treatment of cells with inhibitors specific for the proteasomal degradation pathway largely prevented the AA-induced ACSL4 degradation. We further show that ACSL4 is intrinsically ubiquitinated and that AA treatment can enhance its ubiquitination. Collectively, our studies have identified a novel substrate-induced posttranslational regulatory mechanism by which AA downregulates ACSL4 protein expression in hepatic cells.
Collapse
Affiliation(s)
- Chin Fung Kelvin Kan
- Department of Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304
| | - Amar Bahadur Singh
- Department of Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304
| | | | - Salman Azhar
- Department of Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304
| | - Jingwen Liu
- Department of Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304
| |
Collapse
|
29
|
Dongiovanni P, Anstee QM, Valenti L. Genetic predisposition in NAFLD and NASH: impact on severity of liver disease and response to treatment. Curr Pharm Des 2014; 19:5219-38. [PMID: 23394097 PMCID: PMC3850262 DOI: 10.2174/13816128113199990381] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 02/01/2013] [Indexed: 02/07/2023]
Abstract
Liver fat deposition related to systemic insulin resistance defines non-alcoholic fatty liver disease (NAFLD) which, when associated with oxidative hepatocellular damage, inflammation, and activation of fibrogenesis, i.e. non-alcoholic steatohepatitis (NASH), can progress towards cirrhosis and hepatocellular carcinoma. Due to the epidemic of obesity, NAFLD is now the most frequent liver disease and the leading cause of altered liver enzymes in Western countries. Epidemiological, familial, and twin studies provide evidence for an element of heritability of NAFLD. Genetic modifiers of disease severity and progression have been identified through genome-wide association studies. These include the Patatin-like phosholipase domain-containing 3 (PNPLA3) gene variant I148M as a major determinant of inter-individual and ethnicity-related differences in hepatic fat content independent of insulin resistance and serum lipid concentration. Association studies confirm that the I148M polymorphism is also a strong modifier of NASH and progressive hepatic injury. Furthermore, a few large multicentre case-control studies have demonstrated a role for genetic variants implicated in insulin signalling, oxidative stress, and fibrogenesis in the progression of NAFLD towards fibrosing NASH, and confirm that hepatocellular fat accumulation and insulin resistance are key operative mechanisms closely involved in the progression of liver damage. It is now important to explore the molecular mechanisms underlying these associations between gene variants and progressive liver disease, and to evaluate their impact on the response to available therapies. It is hoped that this knowledge will offer further insights into pathogenesis, suggest novel therapeutic targets, and could help guide physicians towards individualised therapy that improves clinical outcome.
Collapse
Affiliation(s)
- Paola Dongiovanni
- Department of Pathophysiology and Transplantation, section Internal Medicine, Università degli Studi Milano, UO Medicina Interna1B, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
| | | | | |
Collapse
|
30
|
Tao C, Sifuentes A, Holland WL. Regulation of glucose and lipid homeostasis by adiponectin: effects on hepatocytes, pancreatic β cells and adipocytes. Best Pract Res Clin Endocrinol Metab 2014; 28:43-58. [PMID: 24417945 PMCID: PMC4455885 DOI: 10.1016/j.beem.2013.11.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Adiponectin has received considerable attention for its potential anti-diabetic actions. The adipokine exerts control of glucose and lipid homeostasis via critical effects within the liver, adipose, and pancreas. By stimulating adipogenesis, opposing inflammation, and influencing rates of lipid oxidation and lipolysis, adiponectin critically governs lipid spillover into non-adipose tissues. Ceramide, a cytotoxic and insulin desensitizing lipid metabolite formed when peripheral tissues are exposed to excessive lipid deposition, is potently opposed by adiponectin. Via adiponectin receptors, AdipoR1 and AdipoR2, adiponectin stimulates the deacylation of ceramide- yielding sphingosine for conversion to sphingosine 1-phosphate (S1P) by sphingosine kinase. The resulting conversion from ceramide to S1P promotes survival of functional beta cell mass, allowing for insulin production to meet insulin demands. Alleviation of ceramide burden on the liver allows for improvements in hepatic insulin action. Here, we summarize how adiponectin-induced changes in these tissues lead to improvements in glucose metabolism, highlighting the sphingolipid signaling mechanisms linking adiponectin to each action. ONE SENTENCE SUMMARY: We review the anti-diabetic actions of adiponectin.
Collapse
Affiliation(s)
- Caroline Tao
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - Angelica Sifuentes
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA
| | - William L Holland
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390-8549, USA.
| |
Collapse
|
31
|
Lindgren A, Levin M, Rodrigo Blomqvist S, Wikström J, Ahnmark A, Mogensen C, Böttcher G, Bohlooly-Y M, Borén J, Gan LM, Lindén D. Adiponectin receptor 2 deficiency results in reduced atherosclerosis in the brachiocephalic artery in apolipoprotein E deficient mice. PLoS One 2013; 8:e80330. [PMID: 24324556 PMCID: PMC3855811 DOI: 10.1371/journal.pone.0080330] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 09/26/2013] [Indexed: 01/01/2023] Open
Abstract
Adiponectin has been shown to have beneficial cardiovascular effects and to signal through the adiponectin receptors, AdipoR1 and AdipoR2. The original aim of this study was to investigate the effect of combined AdipoR1 and AdipoR2 deficiency (AdipoR1-/-AdipoR2-/-) on atherosclerosis. However, we made the interesting observation that AdipoR1-/-AdipoR2-/- leads to embryonic lethality demonstrating the critical importance of the adiponectin signalling system during development. We then investigated the effect of AdipoR2-ablation on the progression of atherosclerosis in apolipoprotein E deficient (ApoE-/-) mice. AdipoR2-/-ApoE-/- mice fed an atherogenic diet had decreased plaque area in the brachiocephalic artery compared with AdipoR2+/+ApoE-/- littermate controls as visualized in vivo using an ultrasound biomicroscope and confirmed by histological analyses. The decreased plaque area in the brachiocephalic artery could not be explained by plasma cholesterol levels or inflammatory status. However, accumulation of neutral lipids was decreased in peritoneal macrophages from AdipoR2-/-ApoE-/- mice after incubation with oxidized LDL. This effect was associated with lower CD36 and higher ABCA1 mRNA levels in peritoneal macrophages from AdipoR2-/-ApoE-/- mice compared with AdipoR2+/+ApoE-/- controls after incubation with oxidized LDL. In summary, we show that adiponectin receptors are crucial during embryonic development and that AdipoR2-deficiency slows down the progression of atherosclerosis in the brachiocephalic artery of ApoE-deficient mice.
Collapse
Affiliation(s)
- Anna Lindgren
- Cardiovascular & Metabolic Disease Innovative Medicines, AstraZeneca R&D, Mölndal, Sweden
| | - Malin Levin
- Wallenberg Laboratory for Cardiovascular Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | | | - Johannes Wikström
- Cardiovascular & Metabolic Disease Innovative Medicines, AstraZeneca R&D, Mölndal, Sweden
| | - Andrea Ahnmark
- Cardiovascular & Metabolic Disease Innovative Medicines, AstraZeneca R&D, Mölndal, Sweden
| | - Christina Mogensen
- Cardiovascular & Metabolic Disease Innovative Medicines, AstraZeneca R&D, Mölndal, Sweden
| | - Gerhard Böttcher
- Global Safety Assessment, Pathology Sciences, AstraZeneca R&D, Mölndal, Sweden
| | | | - Jan Borén
- Wallenberg Laboratory for Cardiovascular Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Li-Ming Gan
- Cardiovascular & Metabolic Disease Innovative Medicines, AstraZeneca R&D, Mölndal, Sweden
| | - Daniel Lindén
- Cardiovascular & Metabolic Disease Innovative Medicines, AstraZeneca R&D, Mölndal, Sweden
- * E-mail:
| |
Collapse
|
32
|
Superparamagnetic iron oxide nanoparticles alter expression of obesity and T2D-associated risk genes in human adipocytes. Sci Rep 2013; 3:2173. [PMID: 23838847 PMCID: PMC3707025 DOI: 10.1038/srep02173] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 06/20/2013] [Indexed: 12/26/2022] Open
Abstract
Adipocytes hypertrophy is the main cause of obesity and its affliction such as type 2 diabetes (T2D). Since superparamagnetic iron oxide nanoparticles (SPIONs) are used for a wide range of biomedical/medical applications, we aimed to study the effect of SPIONs on 22 and 29 risk genes (Based on gene wide association studies) for obesity and T2D in human adipocytes. The mRNA expression of lipid and glucose metabolism genes was changed upon the treatment of human primary adipocytes with SPIONs. mRNA of GULP1, SLC30A8, NEGR1, SEC16B, MTCH2, MAF, MC4R, and TMEM195 were severely induced, whereas INSIG2, NAMPT, MTMR9, PFKP, KCTD15, LPL and GNPDA2 were down-regulated upon SPIONs stimulation. Since SEC16B gene assist the phagocytosis of apoptotic cells and this gene were highly expressed upon SPIONs treatment in adipocytes, it is logic to assume that SPIONs may play a crucial role in this direction, which requires more consideration in the future.
Collapse
|
33
|
Anstee QM, Targher G, Day CP. Progression of NAFLD to diabetes mellitus, cardiovascular disease or cirrhosis. Nat Rev Gastroenterol Hepatol 2013; 10:330-44. [PMID: 23507799 DOI: 10.1038/nrgastro.2013.41] [Citation(s) in RCA: 1217] [Impact Index Per Article: 110.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
NAFLD is a spectrum of progressive liver disease that encompasses simple steatosis, NASH, fibrosis and, ultimately, cirrhosis. NAFLD is recognized as the hepatic component of the metabolic syndrome, as these conditions have insulin resistance as a common pathophysiological mechanism. Therefore, NAFLD is strongly associated with type 2 diabetes mellitus and abdominal obesity. As lifestyles have become increasingly sedentary and dietary patterns have changed, the worldwide prevalence of NAFLD has increased dramatically and is projected to be the principal aetiology for liver transplantation within the next decade. Importantly, a growing body of clinical and epidemiological evidence suggests that NAFLD is associated not only with liver-related morbidity and mortality, but also with an increased risk of developing both cardiovascular disease and type 2 diabetes mellitus. This article reviews the evidence that suggests NAFLD is a multisystem disease and the factors that might determine interindividual variation in the development and progression of its major hepatic and extrahepatic manifestations (principally type 2 diabetes mellitus and cardiovascular disease).
Collapse
Affiliation(s)
- Quentin M Anstee
- Liver Research Group, Institute of Cellular Medicine, The Medical School, Newcastle University, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK
| | | | | |
Collapse
|
34
|
Naik A, Košir R, Rozman D. Genomic aspects of NAFLD pathogenesis. Genomics 2013; 102:84-95. [PMID: 23545492 DOI: 10.1016/j.ygeno.2013.03.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 03/19/2013] [Accepted: 03/22/2013] [Indexed: 02/07/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most predominant liver disease worldwide and hepatic manifestation of the metabolic syndrome. Its histology spectrum ranges from steatosis, to steatohepatitis (NASH) that can further progress to cirrhosis and hepatocellular carcinoma (HCC). The increasing incidence of NAFLD has contributed to rising numbers of HCC occurrences. NAFLD progression is governed by genetic susceptibility, environmental factors, lifestyle and features of the metabolic syndrome, many of which overlap with HCC. Gene expression profiling and genome wide association studies have identified novel disease pathways and polymorphisms in genes that may be potential biomarkers of NAFLD progression. However, the multifactorial nature of NAFLD and the limited number of sufficiently powered studies are among the current limitations for validated biomarkers of clinical utility. Further studies incorporating the links between circadian regulation and hepatic metabolism might represent an additional direction in the search for predictive biomarkers of liver disease progression and treatment outcomes.
Collapse
Affiliation(s)
- Adviti Naik
- Faculty of Computer Sciences and Informatics, Tržaška Cesta 25, Ljubljana 1000, University of Ljubljana, Slovenia
| | | | | |
Collapse
|
35
|
Cao CY, Li YY, Zhou YJ, Nie YQ, Wan YJY. The C-681G polymorphism of the PPAR-γ gene is associated with susceptibility to non-alcoholic fatty liver disease. TOHOKU J EXP MED 2013; 227:253-62. [PMID: 22820754 DOI: 10.1620/tjem.227.253] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is defined as excessive accumulation of fatty acid in the liver, a common disease in the world. The research of single nucleotide polymorphisms (SNPs) provides a new approach for managing NAFLD. SNPs may increase or decrease the functions of the target genes and their encoding proteins. Peroxisome proliferator-activated receptor (PPAR) plays a key role in modulating metabolism of hepatic triglycerides and consequently magnitude of NAFLD. In this study, we investigated the effect of three SNPs in the PPAR-γ gene i.e. rs10865710 (C-681G), rs7649970 (C-689T) and rs1801282 (C34G, also termed Pro12Ala) on susceptibility to NAFLD. The participants were selected from our epidemiological survey. Totally 169 participants were enrolled in NAFLD group, and 699 healthy subjects were included as controls. PCR-RFLP was applied to detect the SNPs. The G allele frequency of rs10865710 in NAFLD group (41.1%) was significantly higher than that (34.8%) in controls (p = 0.03). Differences in other two loci (rs7649970 and rs1801282) were not statistically significant between the two groups (p > 0.05). This result was confirmed by haplotype analysis. The GCC haplotype (a set of 3 adjacent SNPs in linkage disequilibrium, corresponding to the three alleles of above polymorphisms in order) was a risk factor for the susceptibility to NAFLD (p = 0.03). This study has revealed that the G allele of rs10865710 in the PPAR-γ gene is associated with the increased susceptibility to NAFLD. Our findings may provide novel diagnostic biomarkers and therapeutic targets for NAFLD.
Collapse
Affiliation(s)
- Chuang-Yu Cao
- Department of Gastroenterology and Hepatology, Guangzhou Institute of Clinical Medicine, Guangzhou First Municipal People's Hospital, Guangzhou Medical College, Guangzhou, PR China
| | | | | | | | | |
Collapse
|
36
|
Sahebkar A. Does PPARγ2 gene Pro12Ala polymorphism affect nonalcoholic fatty liver disease risk? Evidence from a meta-analysis. DNA Cell Biol 2013; 32:188-98. [PMID: 23448101 DOI: 10.1089/dna.2012.1947] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Genetic factors can substantially contribute to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). A missense Pro12Ala substitution in the PPARγ2 gene (rs1801282) has been studied in relation with NAFLD risk in different ethnic groups, but findings have been inconclusive. The aim of this was to evaluate the association between rs1801282 and NAFLD through meta-analysis of all relevant published evidence. A systematic search to find eligible studies was performed in Medline, HuGE Navigator, and SCOPUS databases. The strength of association was evaluated using odds ratios with 95% confidence intervals obtained from a random effect approach and under additive, dominant, co-dominant, recessive, and allelic contrast models. Seven studies comprising 1474 cases and 2259 controls met the eligibility criteria and included in the meta-analysis. Combined results did not indicate any predisposing or protective effect for rs1801282 under any of the assessed modes of inheritance. The rate of heterogeneity was generally high due to the inter-study variations in terms of age, gender, and ethnicity. Evidence from the current meta-analysis indicated that rs1801282 variants are not associated with NAFLD risk. Future large-scale studies are required to substantiate the present findings.
Collapse
Affiliation(s)
- Amirhossein Sahebkar
- Biotechnology Research Center and School of Pharmacy, Cardiovascular Research Center, Mashhad University of Medical Sciences (MUMS), Mashhad, Iran.
| |
Collapse
|
37
|
Li YY. Genetic and epigenetic variants influencing the development of nonalcoholic fatty liver disease. World J Gastroenterol 2012; 18:6546-51. [PMID: 23236228 PMCID: PMC3516206 DOI: 10.3748/wjg.v18.i45.6546] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 07/24/2012] [Accepted: 08/14/2012] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is common worldwide. The importance of genetic and epigenetic changes in etiology and pathogenesis of NAFLD has been increasingly recognized. However, the exact mechanism is largely unknown. A large number of single nucleotide polymorphisms (SNPs) related to NAFLD has been documented by candidate gene studies (CGSs). Among these genes, peroxisome proliferatoractivated receptor-γ, adiponectin, leptin and tumor necrosis factor-α were frequently reported. Since the introduction of genome-wide association studies (GWASs), there have been significant advances in our understanding of genomic variations of NAFLD. Patatin-like phospholipase domain containing family member A3 (PNPLA3, SNP rs738409, encoding I148M), also termed adiponutrin, has caught most attention. The evidence that PNPLA3 is associated with increased hepatic fat levels and hepatic inflammation has been validated by a series of studies. Epigenetic modification refers to phenotypic changes caused by an adaptive mechanism unrelated to alteration of primary DNA sequences. Epigenetic regulation mainly includes microRNAs (miRs), DNA methylation, histone modifications and ubiquitination, among which miRs are studied most extensively. miRs are small natural single stranded RNA molecules regulating mRNA degradation or translation inhibition, subsequently altering protein expression of target genes. The miR-122, a highly abundant miR accounting for nearly 70% of all miRs in the liver, is significantly under-expressed in NAFLD subjects. Inhibition of miR-122 with an antisense oligonucleotide results in decreased mRNA expression of lipogenic genes and improvement of liver steatosis. The investigation into epigenetic involvement in NAFLD pathogenesis is just at the beginning and needs to be refined. This review summarizes the roles of genetics and epigenetics in the development of NAFLD. The progress made in this field may provide novel diagnostic biomarkers and therapeutic targets for NAFLD management.
Collapse
|
38
|
Bhatt SP, Nigam P, Misra A, Guleria R, Luthra K, Pandey RM, Pasha MAQ. Association of peroxisome proliferator activated receptor-γ gene with non-alcoholic fatty liver disease in Asian Indians residing in north India. Gene 2012; 512:143-7. [PMID: 23031808 DOI: 10.1016/j.gene.2012.09.067] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 08/20/2012] [Accepted: 09/12/2012] [Indexed: 02/08/2023]
Abstract
BACKGROUND Genetics of non-alcoholic fatty liver (NAFLD) in Asian Indians has been inadequately studied. We investigated the association of polymorphisms C161T and Pro12Ala of peroxisome proliferator-activated receptor gamma (PPARγ) with clinical and biochemical parameters in Asian Indians with NAFLD. METHODS In this case-control study, 162 NAFLD cases and 173 controls were recruited. Abdominal ultrasound, clinical and biochemical profiles, fasting insulin levels and value of homeostasis model assessment of insulin resistance were determined. Polymerase chain reaction-restriction fragment length polymorphisms of two polymorphisms were performed. The association of these polymorphisms with clinical and biochemical parameters was analysed. RESULTS Higher frequency of Ala and T alleles of PPARγ was obtained in cases. Ala/Ala genotype of PPARγ (Pro12Ala) was associated with significantly higher serum triglycerides (TG), alkaline phosphatase (ALK) and waist-hip ratio in cases as compared to controls. In C161T polymorphism, TT genotype was significantly increased TG (p=0.04), total cholesterol (p=0.01), ALK (p=0.04) and gamma-glutamyl transpeptidase (p=0.007) in cases. The linkage disequilibrium for these two single-nucleotide polymorphisms of PPARγ was differed in cases (D1=0.1; p=0.006) and controls (D1=0.07; p=0.1). Using a multivariate analysis after adjusting for age, sex and body mass index, the presence of NAFLD was linked to these two polymorphisms (odds ratio 1.64 (95% CI: 1.09-2.45, p=0.05)]. CONCLUSION Asian Indians in north India carrying the alleles Ala and T of PPARγ (Pro12Ala and C161T) polymorphisms are predisposed to develop NAFLD.
Collapse
Affiliation(s)
- Surya Prakash Bhatt
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, India
| | | | | | | | | | | | | |
Collapse
|
39
|
Adams LA, Marsh JA, Ayonrinde OT, Olynyk JK, Ang WQ, Beilin LJ, Mori T, Palmer LJ, Oddy WW, Lye SJ, Pennell CE. Cholesteryl ester transfer protein gene polymorphisms increase the risk of fatty liver in females independent of adiposity. J Gastroenterol Hepatol 2012; 27:1520-7. [PMID: 22414273 DOI: 10.1111/j.1440-1746.2012.07120.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIM Environmental factors including excessive caloric intake lead to disordered lipid metabolism and fatty liver disease (FLD). However, FLD demonstrates heritability suggesting genetic factors are also important. We aimed to use a candidate gene approach to examine the association between FLD and single nucleotide polymorphisms (SNPs) in lipid metabolism genes in the adolescent population-based Western Australian Pregnancy (Raine) Cohort. METHODS A total 951 seventeen year-olds underwent hepatic ultrasound, anthropometric and biochemical characterization, DNA extraction and genotyping for 57 SNPs in seven lipid metabolism genes (ApoB100, ATGL, ABHD5, MTTP, CETP, SREBP-1c, PPARα). Associations were adjusted for metabolic factors and Bonferroni corrected. RESULTS The prevalence of FLD was 16.2% (11.4% male vs 21.2% female, P=0.001). Multivariate analysis of metabolic factors found suprailiac skinfold thickness (SST) to be the major predictor of FLD in females and males (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.08-1.15, P=1.7×10(-10) and OR 1.17, 95%CI 1.13-1.22, P=2.4×10(-11) , respectively). In females, two SNPs in linkage disequilibrium from the CETP gene were associated with FLD: rs12447924 (OR 2.16, 95%CI 1.42-3.32, P=0.0003) and rs12597002 (OR=2.22, 95%CI 1.46-3.41 P=0.0002). In lean homozygotes, the probability of FLD was over 30%, compared with 10-15% in lean heterozygotes and 3-5% in lean wild-types. However, these associations were modified by SST, such that for obese individuals, the probability of FLD was over 30% in all genotype groups. CONCLUSIONS Cholesteryl ester transfer protein gene polymorphisms are associated with an increased risk of FLD in adolescent females. The effect is independent of adiposity in homozygotes, thereby placing lean individuals at a significant risk of FLD.
Collapse
Affiliation(s)
- Leon A Adams
- School of Medicine and Pharmacology, The University of Western Australia (UWA), Australia.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Watkins PA, Ellis JM. Peroxisomal acyl-CoA synthetases. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1411-20. [PMID: 22366061 DOI: 10.1016/j.bbadis.2012.02.010] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 01/12/2012] [Accepted: 02/10/2012] [Indexed: 01/26/2023]
Abstract
Peroxisomes carry out many essential lipid metabolic functions. Nearly all of these functions require that an acyl group-either a fatty acid or the acyl side chain of a steroid derivative-be thioesterified to coenzyme A (CoA) for subsequent reactions to proceed. This thioesterification, or "activation", reaction, catalyzed by enzymes belonging to the acyl-CoA synthetase family, is thus central to cellular lipid metabolism. However, despite our rather thorough understanding of peroxisomal metabolic pathways, surprisingly little is known about the specific peroxisomal acyl-CoA synthetases that participate in these pathways. Of the 26 acyl-CoA synthetases encoded by the human and mouse genomes, only a few have been reported to be peroxisomal, including ACSL4, SLC27A2, and SLC27A4. In this review, we briefly describe the primary peroxisomal lipid metabolic pathways in which fatty acyl-CoAs participate. Then, we examine the evidence for presence and functions of acyl-CoA synthetases in peroxisomes, much of which was obtained before the existence of multiple acyl-CoA synthetase isoenzymes was known. Finally, we discuss the role(s) of peroxisome-specific acyl-CoA synthetase isoforms in lipid metabolism.
Collapse
|
41
|
Ruść A, Sieczkowska H, Krzęcio E, Antosik K, Zybert A, Koćwin-Podsiadła M, Kamiński S. The association between acyl-CoA synthetase (ACSL4) polymorphism and intramuscular fat content in (Landrace × Yorkshire) × Duroc pigs. Meat Sci 2011; 89:440-3. [DOI: 10.1016/j.meatsci.2011.05.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 05/11/2011] [Accepted: 05/12/2011] [Indexed: 11/28/2022]
|
42
|
Hernaez R. Genetic factors associated with the presence and progression of nonalcoholic fatty liver disease: a narrative review. GASTROENTEROLOGIA Y HEPATOLOGIA 2011; 35:32-41. [PMID: 22093607 DOI: 10.1016/j.gastrohep.2011.08.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 08/04/2011] [Indexed: 12/25/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world. Whereas insulin resistance and obesity are considered major risk factors for the development and progression of NAFLD, the genetic underpinnings are unclear. Before 2008, candidate gene studies based on prior knowledge of pathophysiology of fatty liver yielded conflicting results. In 2008, Romeo et al. published the first genome wide association study and reported the strongest genetic signal for the presence of fatty liver (PNPLA3, patatin-like phospholipase domain containing 3; rs738409). Since then, two additional genome wide scans were published and identified 9 additional genetic variants. Whereas these results shed light into the understanding of the genetics of NAFLD, most of associations have not been replicated in independent samples and, therefore, remain undetermined the significance of these findings. This review aims to summarize the understanding of genetic epidemiology of NAFLD and highlights the gaps in knowledge.
Collapse
Affiliation(s)
- Ruben Hernaez
- Department of Medicine, The Johns Hopkins School of Medicine, Baltimore, MD 21287, USA.
| |
Collapse
|
43
|
|
44
|
Siitonen N, Pulkkinen L, Lindström J, Kolehmainen M, Schwab U, Eriksson JG, Ilanne-Parikka P, Keinänen-Kiukaanniemi S, Tuomilehto J, Uusitupa M. Association of ADIPOR2 gene variants with cardiovascular disease and type 2 diabetes risk in individuals with impaired glucose tolerance: the Finnish Diabetes Prevention Study. Cardiovasc Diabetol 2011; 10:83. [PMID: 21943112 PMCID: PMC3196906 DOI: 10.1186/1475-2840-10-83] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2011] [Accepted: 09/24/2011] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Adiponectin is an adipokine with insulin-sensitising and anti-atherogenic effects. Two receptors for adiponectin, ADIPOR1 and ADIPOR2, have been characterized that mediate effects of adiponectin in various tissues. We examined whether genetic variation in ADIPOR2 predicts the development of cardiovascular disease (CVD) and/or Type 2 Diabetes (T2DM) in individuals with impaired glucose tolerance (IGT) participating the Finnish Diabetes Prevention Study (DPS). METHODS CVD morbidity and mortality data were collected during a median follow-up of 10.2 years (range 1-13 years) and conversion from IGT to T2DM was assessed during a median follow-up of 7 years (range 1-11 years). Altogether eight SNPs in the ADIPOR2 locus were genotyped in 484 participants of the DPS. Moreover, the same SNPs were genotyped and the mRNA expression levels of ADIPOR2 were determined in peripheral blood mononuclear cells and subcutaneous adipose tissue samples derived from 56 individuals participating in the Genobin study. RESULTS In the DPS population, four SNPs (rs10848554, rs11061937, rs1058322, rs16928751) were associated with CVD risk, and two remained significant (p = 0.014 for rs11061937 and p = 0.020 for rs1058322) when all four were included in the same multi-SNP model. Furthermore, the individuals homozygous for the rare minor alleles of rs11061946 and rs11061973 had increased risk of converting from IGT to T2DM. Allele-specific differences in the mRNA expression levels for the rs1058322 variant were seen in peripheral blood mononuclear cells derived from participants of the Genobin study. CONCLUSIONS Our results suggest that SNPs in the ADIPOR2 may modify the risk of CVD in individuals with IGT, possibly through alterations in the mRNA expression levels. In addition an independent genetic signal in ADIPOR2 locus may have an impact on the risk of developing T2DM in individuals with IGT. TRIAL REGISTRATION NUMBER ClinicalTrials.gov NCT00518167.
Collapse
Affiliation(s)
- Niina Siitonen
- Department of Clinical Nutrition and Food and Health Research Centre, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Leena Pulkkinen
- Department of Clinical Nutrition and Food and Health Research Centre, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Jaana Lindström
- Department of Health Promotion and Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland
- Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Marjukka Kolehmainen
- Department of Clinical Nutrition and Food and Health Research Centre, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Ursula Schwab
- Department of Clinical Nutrition and Food and Health Research Centre, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
- Institute of Medicine, Clinical Medicine, Kuopio University Hospital, Kuopio, Finland
| | - Johan G Eriksson
- Department of Health Promotion and Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland
- Folkhalsan Research Centre, Helsinki, Finland
- Department of General Practice and Primary Health Care, University of Helsinki, Helsinki, Finland
- Vasa Central Hospital, Vasa, Finland
- Unit of General Practice, Helsinki University Central Hospital, Helsinki, Finland
| | - Pirjo Ilanne-Parikka
- Diabetes Centre, Finnish Diabetes Association, Tampere, Finland
- Science Centre, Pirkanmaa Hospital District, Tampere University Hospital, Tampere, Finland
| | - Sirkka Keinänen-Kiukaanniemi
- Institute of Health Sciences, University of Oulu, Oulu, Finland
- Unit of General Practice, Oulu University Hospital, Oulu, Finland
- Health Centre of Oulu, Oulu Finland
| | - Jaakko Tuomilehto
- Department of Health Promotion and Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland
- Department of Public Health, University of Helsinki, Helsinki, Finland
- South Ostrobothnia Central Hospital, Seinäjoki, Finland
- Department of Preventive and Clinical Medicine, Danube-Universität Krems, Krems, Austria
| | - Matti Uusitupa
- Department of Clinical Nutrition and Food and Health Research Centre, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
- Research Unit, Kuopio University Hospital, Kuopio, Finland
| |
Collapse
|
45
|
Cai T, Dufour JF, Muellhaupt B, Gerlach T, Heim M, Moradpour D, Cerny A, Malinverni R, Kaddai V, Bochud M, Negro F, Bochud PY. Viral genotype-specific role of PNPLA3, PPARG, MTTP, and IL28B in hepatitis C virus-associated steatosis. J Hepatol 2011; 55:529-535. [PMID: 21236304 DOI: 10.1016/j.jhep.2010.12.020] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 11/06/2010] [Accepted: 12/06/2010] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Steatosis is a prominent feature of hepatitis C, especially in patients infected with genotype 3. The analysis of genetic polymorphisms influencing steatosis in chronic hepatitis C has been limited by the studies' small sample size, and important single nucleotide polymorphisms (SNPs), such as those in the patatin-like phospholipase family 3 protein (PNPLA3), were never evaluated. METHODS We analyzed the role of SNPs, from 19 systematically selected candidate genes, on steatosis in 626 Caucasian hepatitis C virus (HCV) infected patients. SNPs were extracted from a genome-wide association-generated dataset. Associations of alleles with the presence and/or different severity of steatosis were evaluated by univariate and multivariate logistic regression, accounting for all relevant covariates. RESULTS The risk of steatosis was increased by carriage of I148M in PNPLA3, but only in patients with HCV genotypes non-3 (odds ratio [OR]=1.9, 95% confidence interval [CI]=1.6-2.3, p<0.001) and similar, albeit weaker associations were found for SNPs in peroxisome proliferator-activated receptor-γ (PPARG) and interleukin-28B (IL28B). Carriage of a SNP in the microsomal triglyceride transfer protein (MTTP) increased the risk of steatosis, but only in patients with HCV genotype 3 (rs1800803, OR=3.4, 95% CI=2.4-4.9, p=0.001). CONCLUSIONS The rs738409 SNP in PNPLA3 is associated with an increased risk of steatosis in patients infected with HCV genotypes non-3. Host genes affect steatosis depending on the infecting HCV genotype, suggesting their interaction with viral factors.
Collapse
Affiliation(s)
- Tao Cai
- Infectious Diseases Service, Department of Medicine, University Hospital and University of Lausanne, Switzerland; Institute of Microbiology, University Hospital and University of Lausanne, Switzerland
| | | | - Beat Muellhaupt
- Division of Gastroenterology and Hepatology, University Hospital, Zurich, Switzerland
| | - Tilman Gerlach
- Division of Gastroenterology, Canton Hospital, St. Gallen, Switzerland
| | - Markus Heim
- Division of Gastroenterology and Hepatology, University Hospital, Basel, Switzerland
| | - Darius Moradpour
- Division of Gastroenterology and Hepatology, CHUV, Lausanne, Switzerland
| | | | | | - Vincent Kaddai
- Division of Clinical Pathology, University Hospitals, Geneva, Switzerland
| | - Murielle Bochud
- Institute of Social and Preventive Medicine, CHUV, Lausanne, Switzerland
| | - Francesco Negro
- Division of Clinical Pathology, University Hospitals, Geneva, Switzerland; Division of Gastroenterology and Hepatology, University Hospitals, Geneva, Switzerland.
| | - Pierre-Yves Bochud
- Infectious Diseases Service, Department of Medicine, University Hospital and University of Lausanne, Switzerland; Institute of Microbiology, University Hospital and University of Lausanne, Switzerland
| |
Collapse
|
46
|
Anstee QM, Daly AK, Day CP. Genetic modifiers of non-alcoholic fatty liver disease progression. Biochim Biophys Acta Mol Basis Dis 2011; 1812:1557-66. [PMID: 21840395 DOI: 10.1016/j.bbadis.2011.07.017] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 07/28/2011] [Accepted: 07/29/2011] [Indexed: 12/11/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is now recognised as the most common cause of liver dysfunction worldwide. However, whilst the majority of individuals who exhibit features of the metabolic syndrome including obesity and insulin resistance will develop steatosis, only a minority progress to steatohepatitis, fibrosis and cirrhosis. Subtle inter-patient genetic variations and environment interact to determine disease phenotype and influence progression. A decade after the sequencing of the human genome, the comprehensive study of genomic variation offers new insights into the modifier genes, pathogenic mechanisms and is beginning to suggest novel therapeutic targets. We review the current status of the field with particular focus on advances from recent genome-wide association studies.
Collapse
Affiliation(s)
- Quentin M Anstee
- Liver Research Group, Instiutte of Cellular Medicine, Teh Medical School, Newcastle University, Framlington Place, Newcaltle-upon-Type, NE2 4HHK, UK
| | | | | |
Collapse
|
47
|
Liang X, Hu M, Rogers CQ, Shen Z, You M. Role of SIRT1-FoxO1 signaling in dietary saturated fat-dependent upregulation of liver adiponectin receptor 2 in ethanol-administered mice. Antioxid Redox Signal 2011; 15:425-35. [PMID: 21194380 PMCID: PMC3118604 DOI: 10.1089/ars.2010.3780] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The aim of the present study is to examine the effects of dietary saturated fatty acids on liver adiponectin receptor 1 (AdipoR1) and adiponectin receptor 2 (AdipoR2) in ethanol-administered animals and in ethanol-exposed cultured hepatic cells, and to explore the underlying molecular mechanisms. The mRNA and protein levels of hepatic AdipoR2 were selectively increased by chronic ethanol feeding to mice consuming a diet high in saturated fat (HSF). Administration of an HSF diet blocked hyperacetylation of forkhead transcription factor 1 (FoxO1), a known target of sirtuin 1 (SIRT1), increased nuclear FoxO1 protein levels, and enhanced association of FoxO1 with the AdipoR2 promoter in the livers of ethanol-fed mice. Treatment of cultured hepatic cells with palmitic acid (a major saturated fatty acid in HSF diet) in the presence of ethanol robustly increased AdipoR2 mRNA expression and enhanced activity of a mouse AdipoR2 promoter. Knocking down SIRT1 or FoxO1 using the small silencing SIRT1 or FoxO1 plasmid blunted the palmitic acid effect. Taken together, these results reveal that dietary saturated fat selectively upregulates hepatic AdipoR2 through modulation of SIRT1-FoxO1 signaling in ethanol fed mice, and this effect may contribute to the protective effect of the HSF diet against alcoholic fatty liver.
Collapse
Affiliation(s)
- Xiaomei Liang
- Departments of Molecular Pharmacology and Physiology, University of South Florida Health Sciences Center, Tampa, Florida 33612, USA
| | | | | | | | | |
Collapse
|
48
|
Buechler C, Wanninger J, Neumeier M. Adiponectin, a key adipokine in obesity related liver diseases. World J Gastroenterol 2011; 17:2801-11. [PMID: 21734787 PMCID: PMC3120939 DOI: 10.3748/wjg.v17.i23.2801] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Revised: 11/17/2010] [Accepted: 11/24/2010] [Indexed: 02/06/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) comprising hepatic steatosis, non-alcoholic steatohepatitis (NASH), and progressive liver fibrosis is considered the most common liver disease in western countries. Fatty liver is more prevalent in overweight than normal-weight people and liver fat positively correlates with hepatic insulin resistance. Hepatic steatosis is regarded as a benign stage of NAFLD but may progress to NASH in a subgroup of patients. Besides liver biopsy no diagnostic tools to identify patients with NASH are available, and no effective treatment has been established. Visceral obesity is a main risk factor for NAFLD and inappropriate storage of triglycerides in adipocytes and higher concentrations of free fatty acids may add to increased hepatic lipid storage, insulin resistance, and progressive liver damage. Most of the adipose tissue-derived proteins are elevated in obesity and may contribute to systemic inflammation and liver damage. Adiponectin is highly abundant in human serum but its levels are reduced in obesity and are even lower in patients with hepatic steatosis or NASH. Adiponectin antagonizes excess lipid storage in the liver and protects from inflammation and fibrosis. This review aims to give a short survey on NAFLD and the hepatoprotective effects of adiponectin.
Collapse
|
49
|
Monda KL, North KE, Hunt SC, Rao DC, Province MA, Kraja AT. The genetics of obesity and the metabolic syndrome. Endocr Metab Immune Disord Drug Targets 2011; 10:86-108. [PMID: 20406164 DOI: 10.2174/187153010791213100] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 04/04/2010] [Indexed: 12/19/2022]
Abstract
In this review, we discuss the genetic architecture of obesity and the metabolic syndrome, highlighting recent advances in identifying genetic variants and loci responsible for a portion of the variation in components of the metabolic syndrome, namely, adiposity traits, serum HDL and triglycerides, blood pressure, and glycemic traits. We focus particularly on recent progress from large-scale genome-wide association studies (GWAS), by detailing their successes and how lessons learned can pave the way for future discovery. Results from recent GWAS coalesce with earlier work suggesting numerous interconnections between obesity and the metabolic syndrome, developed through several potentially pleiotropic effects. We detail recent work by way of a case study on the cadherin 13 gene and its relation with adiponectin in the HyperGEN and the Framingham Heart Studies, and its association with obesity and the metabolic syndrome. We provide also a gene network analysis of recent variants related to obesity and metabolic syndrome discovered through genome-wide association studies, and 4 gene networks based on searching the NCBI database.
Collapse
Affiliation(s)
- Keri L Monda
- Department of Epidemiology, University of North Carolina at Chapel Hill, USA.
| | | | | | | | | | | |
Collapse
|
50
|
Hooper AJ, Adams LA, Burnett JR. Genetic determinants of hepatic steatosis in man. J Lipid Res 2011; 52:593-617. [PMID: 21245030 DOI: 10.1194/jlr.r008896] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatic steatosis is one of the most common liver disorders in the general population. The main cause of hepatic steatosis is nonalcoholic fatty liver disease (NAFLD), representing the hepatic component of the metabolic syndrome, which is characterized by type 2 diabetes, obesity, and dyslipidemia. Insulin resistance and excess adiposity are considered to play key roles in the pathogenesis of NAFLD. Although the risk factors for NAFLD are well established, the genetic basis of hepatic steatosis is largely unknown. Here we review recent progress on genomic variants and their association with hepatic steatosis and discuss the potential impact of these genetic studies on clinical practice. Identifying the genetic determinants of hepatic steatosis will lead to a better understanding of the pathogenesis and progression of NAFLD.
Collapse
Affiliation(s)
- Amanda J Hooper
- Department of Core Clinical Pathology and Biochemistry, Royal Perth Hospital, Perth, Australia
| | | | | |
Collapse
|