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Li Y, Zheng M, Limbara S, Zhang S, Yu Y, Yu L, Jiao J. Effects of the Pituitary-targeted Gland Axes on Hepatic Lipid Homeostasis in Endocrine-associated Fatty Liver Disease-A Concept Worth Revisiting. J Clin Transl Hepatol 2024; 12:416-427. [PMID: 38638376 PMCID: PMC11022059 DOI: 10.14218/jcth.2023.00421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 12/28/2023] [Accepted: 01/03/2024] [Indexed: 04/20/2024] Open
Abstract
Hepatic lipid homeostasis is not only essential for maintaining normal cellular and systemic metabolic function but is also closely related to the steatosis of the liver. The controversy over the nomenclature of non-alcoholic fatty liver disease (NAFLD) in the past three years has once again sparked in-depth discussions on the pathogenesis of this disease and its impact on systemic metabolism. Pituitary-targeted gland axes (PTGA), an important hormone-regulating system, are indispensable in lipid homeostasis. This review focuses on the roles of thyroid hormones, adrenal hormones, sex hormones, and their receptors in hepatic lipid homeostasis, and summarizes recent research on pituitary target gland axes-related drugs regulating hepatic lipid metabolism. It also calls on researchers and clinicians to recognize the concept of endocrine-associated fatty liver disease (EAFLD) and to re-examine human lipid metabolism from the macroscopic perspective of homeostatic balance.
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Affiliation(s)
- Yifang Li
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
| | - Meina Zheng
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
| | - Steven Limbara
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
| | - Shanshan Zhang
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
| | - Yutao Yu
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
| | - Le Yu
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
| | - Jian Jiao
- Department of Gastroenterology & Hepatology, China-Japan Union Hospital, Jilin University, Changchun, Jilin, China
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Charlot A, Bringolf A, Mallard J, Charles AL, Niederhoffer N, Duteil D, Pagano AF, Geny B, Zoll J. Hypercaloric low-carbohydrate high-fat diet protects against the development of nonalcoholic fatty liver disease in obese mice in contrast to isocaloric Western diet. Front Nutr 2024; 11:1366883. [PMID: 38571752 PMCID: PMC10987868 DOI: 10.3389/fnut.2024.1366883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 03/11/2024] [Indexed: 04/05/2024] Open
Abstract
Objective Obesity and metabolic complications, such as type 2 diabetes and nonalcoholic fatty liver disease (NAFLD), are one of the greatest public health challenges of the 21st century. The major role of high sugar and carbohydrate consumption rather than caloric intake in obesity and NAFLD pathophysiology remains a subject of debate. A low-carbohydrate but high-fat diet (LCHFD) has shown promising results in obesity management, but its effects in preventing NAFLD need to be detailed. This study aims to compare the effects of a LCHFD with a high-fat high-sugar obesogenic Western diet (WD) on the progression of obesity, type 2 diabetes, and nonalcoholic fatty liver disease. Methods Male C57BL/6J mice were initially fed a WD for 10 weeks. Subsequently, they were either switched to a LCHFD or maintained on the WD for an additional 6 weeks. Hepatic effects of the diet were explored by histological staining and RT-qPCR. Results After the initial 10 weeks WD feeding, LCHF diet demonstrated effectiveness in halting weight gain, maintaining a normal glucose tolerance and insulin levels, in comparison to the WD-fed mice, which developed obesity, glucose intolerance, increased insulin levels and induced NAFLD. In the liver, LCHFD mitigated the accumulation of hepatic triglycerides and the increase in Fasn relative gene expression compared to the WD mice. Beneficial effects of the LCHFD occurred despite a similar calorie intake compared to the WD mice. Conclusion Our results emphasize the negative impact of a high sugar/carbohydrate and lipid association for obesity progression and NAFLD development. LCHFD has shown beneficial effects for NAFLD management, notably improving weight management, and maintaining a normal glucose tolerance and liver health.
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Affiliation(s)
- Anouk Charlot
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
- Faculty of Sport Sciences, University of Strasbourg, Strasbourg, France
| | - Anthony Bringolf
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
| | - Joris Mallard
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
- Faculty of Sport Sciences, University of Strasbourg, Strasbourg, France
- Institute of Cancerology Strasbourg Europe (ICANS), Strasbourg, France
| | - Anne-Laure Charles
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
- Faculty of Medicine, University of Strasbourg, Strasbourg, France
| | - Nathalie Niederhoffer
- Biomedicine Research Center of Strasbourg (CRBS), UR7296, NeuroCardiovascular Pharmacology and Toxicology Laboratory (LPTNC), University of Strasbourg, Strasbourg, France
| | - Delphine Duteil
- University of Strasbourg, CNRS, Inserm, IGBMC UMR 7104-UMR-S 1258, Illkirch, France
| | - Allan F. Pagano
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
- Faculty of Sport Sciences, University of Strasbourg, Strasbourg, France
| | - Bernard Geny
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
- Service de Physiologie et explorations fonctionnelles, University Hospital of Strasbourg, Strasbourg, France
| | - Joffrey Zoll
- Biomedicine Research Center of Strasbourg (CRBS), UR 3072, “Mitochondrie, Stress oxydant et Plasticité musculaire”, University of Strasbourg, Strasbourg, France
- Faculty of Medicine, University of Strasbourg, Strasbourg, France
- Service de Physiologie et explorations fonctionnelles, University Hospital of Strasbourg, Strasbourg, France
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3
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You H, Yuan D, Li Q, Zhang N, Kong D, Yu T, Liu X, Liu X, Zhou R, Kong F, Zheng K, Tang R. Hepatitis B virus X protein increases LASP1 SUMOylation to stabilize HER2 and facilitate hepatocarcinogenesis. Int J Biol Macromol 2023; 226:996-1009. [PMID: 36473530 DOI: 10.1016/j.ijbiomac.2022.11.312] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 07/05/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022]
Abstract
The hepatitis B virus (HBV) X protein (HBX), a viral macromolecule, plays a vital role in the development of HBV-related hepatocellular carcinoma (HCC). Increased expression of HER2 is linked to HBV infection, and HBX is responsible for HER2 upregulation in HCC. Nevertheless, the underlying molecular mechanisms are not yet fully understood. In the study, we discovered that HBX promoted HER2 expression to facilitate the sensitization of the insulin signaling pathway and enhance the growth and migration of HCC cells. Mechanistically, the viral protein enhanced the stability of HER2 by preventing its ubiquitination-mediated proteasomal degradation through LASP1, which could bind to HER2. Furthermore, increased SUMOylation of LASP1 contributed to the upregulation of HER2 and the interaction of LASP1 with HER2. In addition, RANBP2 and RANGAP1 were found to interact with LASP1 and promote SUMOylation of LASP1 to upregulate HER2 expression in HBX-associated hepatoma cells. In summary, our work provides a novel insight into hepatocarcinogenesis mediated by HBX and estimates the detailed mechanisms related to the increase in HER2 regulated by the viral protein, which might help provide a theoretical basis for identifying novel targets for HBV-positive HCC treatment.
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Affiliation(s)
- Hongjuan You
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Dongchen Yuan
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Qi Li
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Ning Zhang
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Delong Kong
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Tong Yu
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiangye Liu
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiaomei Liu
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Rui Zhou
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Fanyun Kong
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China.
| | - Kuiyang Zheng
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China; National Demonstration Center for Experimental Basic Medical Sciences Education, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Renxian Tang
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogenic Biology and Immunology, Xuzhou Medical University, Xuzhou, Jiangsu, China; National Demonstration Center for Experimental Basic Medical Sciences Education, Xuzhou Medical University, Xuzhou, Jiangsu, China.
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Jiang JL, Qian JF, Xiao DH, Liu X, Zhu F, Wang J, Xing ZX, Xu DL, Xue Y, He YH. Relationship of familial cytochrome P450 4V2 gene mutation with liver cirrhosis: A case report and review of the literature. World J Clin Cases 2022; 10:10346-10357. [PMID: 36246827 PMCID: PMC9561572 DOI: 10.12998/wjcc.v10.i28.10346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 08/02/2022] [Accepted: 08/25/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Many genetic and metabolic diseases affect the liver, but diagnosis can be difficult because these diseases may have complex clinical manifestations and diverse clinical patterns. There is also incomplete clinical knowledge of these many different diseases and limitations of current testing methods.
CASE SUMMARY We report a 53-year-old female from a rural area in China who was hospitalized for lower limb edema, abdominal distension, cirrhosis, and hypothyroidism. We excluded the common causes of liver disease (drinking alcohol, using traditional Chinese medicines, hepatitis virus infection, autoimmunity, and hepatolenticular degeneration). When she was 23-years-old, she developed night-blindness that worsened to complete blindness, with no obvious cause. Her parents were first cousins, and both were alive. Analysis of the patient’s family history indicated that all 5 siblings had night blindness and impaired vision; one sister was completely blind; and another sister had night-blindness complicated with cirrhosis and subclinical hypothyroidism. Entire exome sequencing showed that the patient, parents, and siblings all had mutations in the cytochrome P450 4V2 gene (CYP4V2). The CYP4V2 mutations of the parents and two sisters were heterozygous, and the others were homozygous. Two siblings also had heterozygous dual oxidase activator 2 (DUOXA2) mutations.
CONCLUSION Mutations in the CYP4V2 gene may affect lipid metabolism and lead to chronic liver injury, fibrosis, and cirrhosis.
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Affiliation(s)
- Jin-Lian Jiang
- Department of Infectious Diseases, Affiliated Hospital of Zunyi Medical University, Zunyi 563003, Guizhou Province, China
| | - Jiang-Fu Qian
- Department of Digestion, Dafang County People’s Hospital, Bijie 551600, Guizhou Province, China
| | - De-Hui Xiao
- Department of Digestion, Dafang County People’s Hospital, Bijie 551600, Guizhou Province, China
| | - Xia Liu
- Department of Infectious Diseases, Affiliated Hospital of Zunyi Medical University, Zunyi 563003, Guizhou Province, China
| | - Fang Zhu
- Department of Digestion, Dafang County People’s Hospital, Bijie 551600, Guizhou Province, China
| | - Jie Wang
- Department of Infectious Diseases, Affiliated Hospital of Zunyi Medical University, Zunyi 563003, Guizhou Province, China
| | - Zhou-Xiong Xing
- Department of Intensive Care, Affiliated Hospital of Zunyi Medical University, Zunyi 563000, Guizhou Province, China
| | - De-Lin Xu
- Department of Cell Biology, Zunyi Medical University, Zunyi 563099, Guizhou Province, China
| | - Yuan Xue
- Department of Liver Diseases, the Third People’s Hospital of Changzhou, Changzhou 213000, Jiangsu Province, China
| | - Yi-Huai He
- Department of Infectious Diseases, Affiliated Hospital of Zunyi Medical University, Zunyi 563003, Guizhou Province, China
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Liao CJ, Huang PS, Chien HT, Lin TK, Yeh CT, Lin KH. Effects of Thyroid Hormones on Lipid Metabolism Pathologies in Non-Alcoholic Fatty Liver Disease. Biomedicines 2022; 10:biomedicines10061232. [PMID: 35740254 PMCID: PMC9219876 DOI: 10.3390/biomedicines10061232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 02/01/2023] Open
Abstract
The typical modern lifestyle contributes to the development of many metabolic-related disorders, as exemplified by metabolic syndrome. How to prevent, resolve, or avoid subsequent deterioration of metabolic disturbances and the development of more serious diseases has become an important and much-discussed health issue. Thus, the question of the physiological and pathological roles of thyroid hormones (THs) in metabolism has never gone out of fashion. Although THs influence almost all organs, the liver is one of the most important targets as well as the hub of metabolic homeostasis. When this homeostasis is out of balance, diseases may result. In the current review, we summarize the common features and actions of THs, first focusing on their effects on lipid metabolism in the liver. In the second half of the review, we turn to a consideration of non-alcoholic fatty liver disease (NAFLD), a disease characterized by excessive accumulation of fat in the liver that is independent of heavy alcohol consumption. NAFLD is a growing health problem that currently affects ~25% of the world’s population. Unfortunately, there are currently no approved therapies specific for NAFLD, which, if left uncontrolled, may progress to more serious diseases, such as cirrhosis or liver cancer. This absence of effective treatment can also result in the development of non-alcoholic steatohepatitis (NASH), an aggressive form of NAFLD that is the leading cause of liver transplantation in the United States. Because THs play a clear role in hepatic fat metabolism, their potential application in the prevention and treatment of NAFLD has attracted considerable research attention. Studies that have investigated the use of TH-related compounds in the management of NAFLD are also summarized in the latter part of this review. An important take-home point of this review is that a comprehensive understanding of the physiological and pathological roles of THs in liver fat metabolism is possible, despite the complexities of this regulatory axis—an understanding that has clinical value for the specific management of NAFLD.
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Affiliation(s)
- Chia-Jung Liao
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (C.-J.L.); (P.-S.H.)
| | - Po-Shuan Huang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (C.-J.L.); (P.-S.H.)
| | - Hui-Tzu Chien
- Department of Nutrition and Health Sciences, Chang Gung University of Science and Technology, Taoyuan 333, Taiwan;
- Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 333, Taiwan
| | - Tzu-Kang Lin
- Neurosurgery, Fu Jen Catholic University Hospital School of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan;
| | - Chau-Ting Yeh
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan;
| | - Kwang-Huei Lin
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan; (C.-J.L.); (P.-S.H.)
- Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 333, Taiwan
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan;
- Department of Biochemistry, Chang Gung University, 259 Wen-Hwa 1 Road, Taoyuan 333, Taiwan
- Correspondence: ; Tel./Fax: +886-3-2118263
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Transcriptional Regulation of Hepatic Autophagy by Nuclear Receptors. Cells 2022; 11:cells11040620. [PMID: 35203271 PMCID: PMC8869834 DOI: 10.3390/cells11040620] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 02/04/2023] Open
Abstract
Autophagy is an adaptive self-eating process involved in degradation of various cellular components such as carbohydrates, lipids, proteins, and organelles. Its activity plays an essential role in tissue homeostasis and systemic metabolism in response to diverse challenges, including nutrient depletion, pathogen invasion, and accumulations of toxic materials. Therefore, autophagy dysfunctions are intimately associated with many human diseases such as cancer, neurodegeneration, obesity, diabetes, infection, and aging. Although its acute post-translational regulation is well described, recent studies have also shown that autophagy can be controlled at the transcriptional and post-transcriptional levels. Nuclear receptors (NRs) are in general ligand-dependent transcription factors consisting of 48 members in humans. These receptors extensively control transcription of a variety of genes involved in development, metabolism, and inflammation. In this review, we discuss the roles and mechanisms of NRs in an aspect of transcriptional regulation of hepatic autophagy, and how the NR-driven autophagy pathway can be harnessed to treat various liver diseases.
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Kapri D, Fanibunda SE, Vaidya VA. Thyroid hormone regulation of adult hippocampal neurogenesis: Putative molecular and cellular mechanisms. VITAMINS AND HORMONES 2021; 118:1-33. [PMID: 35180924 DOI: 10.1016/bs.vh.2021.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Adult hippocampal neurogenesis is sensitive to perturbations in thyroid hormone signaling, with evidence supporting a key role for thyroid hormone and thyroid hormone receptors (TRs) in the regulation of postmitotic progenitor survival and neuronal differentiation. In this book chapter we summarize the current understanding of the effects of thyroid hormone signaling on adult hippocampal progenitor development, and also critically address the role of TRs in regulation of distinct aspects of stage-specific hippocampal progenitor progression. We highlight actions of thyroid hormone on thyroid hormone responsive target genes, and the implications for hippocampal progenitor regulation. Given the influence of thyroid hormone on both mitochondrial and lipid metabolism, we discuss a putative role for regulation of metabolism in the effects of thyroid hormone on adult hippocampal neurogenesis. Finally, we highlight specific ideas that require detailed experimental investigation, and the need for future studies to obtain a deeper mechanistic insight into the influence of thyroid hormone and TRs in the developmental progression of adult hippocampal progenitors.
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Affiliation(s)
- Darshana Kapri
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Sashaina E Fanibunda
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India; Medical Research Centre, Kasturba Health Society, Mumbai, India
| | - Vidita A Vaidya
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.
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8
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The Role and Mechanism of Oxidative Stress and Nuclear Receptors in the Development of NAFLD. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:6889533. [PMID: 34745420 PMCID: PMC8566046 DOI: 10.1155/2021/6889533] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 10/11/2021] [Indexed: 12/12/2022]
Abstract
The overproduction of reactive oxygen species (ROS) and consequent oxidative stress contribute to the pathogenesis of acute and chronic liver diseases. It is now acknowledged that nonalcoholic fatty liver disease (NAFLD) is characterized as a redox-centered disease due to the role of ROS in hepatic metabolism. However, the underlying mechanisms accounting for these alternations are not completely understood. Several nuclear receptors (NRs) are dysregulated in NAFLD, and have a direct influence on the expression of a set of genes relating to the progress of hepatic lipid homeostasis and ROS generation. Meanwhile, the NRs act as redox sensors in response to metabolic stress. Therefore, targeting NRs may represent a promising strategy for improving oxidation damage and treating NAFLD. This review summarizes the link between impaired lipid metabolism and oxidative stress and highlights some NRs involved in regulating oxidant/antioxidant turnover in the context of NAFLD, shedding light on potential therapies based on NR-mediated modulation of ROS generation and lipid accumulation.
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Xiong W, Sun KY, Zhu Y, Zhang X, Zhou YH, Zou X. Metformin alleviates inflammation through suppressing FASN-dependent palmitoylation of Akt. Cell Death Dis 2021; 12:934. [PMID: 34642298 PMCID: PMC8511025 DOI: 10.1038/s41419-021-04235-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/17/2021] [Accepted: 09/27/2021] [Indexed: 12/18/2022]
Abstract
Metformin, traditionally regarded as a hypoglycemic drug, has been studied in other various fields including inflammation. The specific mechanism of metformin’s effect on immune cells remains unclear. Herein, it is verified that LPS-induced macrophages are characterized by enhanced endogenous fatty acid synthesis and the inhibition of fatty acid synthase (FASN) downregulates proinflammatory responses. We further show that metformin could suppress such elevation of FASN as well as proinflammatory activation in macrophages. In vivo, metformin treatment ameliorates dextran sulfate sodium (DSS)-induced colitis through impairing proinflammatory activation of colonic lamina propria mononuclear cells (LPMCs). The reduction of FASN by metformin hinders Akt palmitoylation, which further disturbs Akt membrane attachment and its phosphorylation. Metformin-mediated suppression of FASN/Akt pathway and its downstream MAPK signaling contributes to its anti-inflammatory role in macrophages. From the perspective of immunometabolism, our work points towards metformin utilization as an effective and potential intervention against macrophages-involved inflammatory diseases.
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Affiliation(s)
- Wenfang Xiong
- Department of Gastroenterology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China
| | - Kuo-Yang Sun
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Sports Medicine and Adult Reconstructive Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China
| | - Yan Zhu
- Department of Gastroenterology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China
| | - Xiaoqi Zhang
- Department of Gastroenterology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China.
| | - Yi-Hua Zhou
- Departments of Laboratory Medicine and Infectious Diseases, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China.
| | - Xiaoping Zou
- Department of Gastroenterology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China.
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10
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Thibaut R, Gage MC, Pineda-Torra I, Chabrier G, Venteclef N, Alzaid F. Liver macrophages and inflammation in physiology and physiopathology of non-alcoholic fatty liver disease. FEBS J 2021; 289:3024-3057. [PMID: 33860630 PMCID: PMC9290065 DOI: 10.1111/febs.15877] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 03/05/2021] [Accepted: 04/12/2021] [Indexed: 12/13/2022]
Abstract
Non‐alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome, being a common comorbidity of type 2 diabetes and with important links to inflammation and insulin resistance. NAFLD represents a spectrum of liver conditions ranging from steatosis in the form of ectopic lipid storage, to inflammation and fibrosis in nonalcoholic steatohepatitis (NASH). Macrophages that populate the liver play important roles in maintaining liver homeostasis under normal physiology and in promoting inflammation and mediating fibrosis in the progression of NAFLD toward to NASH. Liver macrophages are a heterogenous group of innate immune cells, originating from the yolk sac or from circulating monocytes, that are required to maintain immune tolerance while being exposed portal and pancreatic blood flow rich in nutrients and hormones. Yet, liver macrophages retain a limited capacity to raise the alarm in response to danger signals. We now know that macrophages in the liver play both inflammatory and noninflammatory roles throughout the progression of NAFLD. Macrophage responses are mediated first at the level of cell surface receptors that integrate environmental stimuli, signals are transduced through multiple levels of regulation in the cell, and specific transcriptional programmes dictate effector functions. These effector functions play paramount roles in determining the course of disease in NAFLD and even more so in the progression towards NASH. The current review covers recent reports in the physiological and pathophysiological roles of liver macrophages in NAFLD. We emphasise the responses of liver macrophages to insulin resistance and the transcriptional machinery that dictates liver macrophage function.
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Affiliation(s)
- Ronan Thibaut
- Cordeliers Research Centre, INSERM, IMMEDIAB Laboratory, Sorbonne Université, Université de Paris, France
| | - Matthew C Gage
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Inès Pineda-Torra
- Department of Medicine, Centre for Cardiometabolic and Vascular Science, University College London, UK
| | - Gwladys Chabrier
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Nicolas Venteclef
- Cordeliers Research Centre, INSERM, IMMEDIAB Laboratory, Sorbonne Université, Université de Paris, France
| | - Fawaz Alzaid
- Cordeliers Research Centre, INSERM, IMMEDIAB Laboratory, Sorbonne Université, Université de Paris, France
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11
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Olichwier A, Balatskyi VV, Wolosiewicz M, Ntambi JM, Dobrzyn P. Interplay between Thyroid Hormones and Stearoyl-CoA Desaturase 1 in the Regulation of Lipid Metabolism in the Heart. Int J Mol Sci 2020; 22:ijms22010109. [PMID: 33374300 PMCID: PMC7796080 DOI: 10.3390/ijms22010109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/17/2020] [Accepted: 12/21/2020] [Indexed: 12/19/2022] Open
Abstract
Stearoyl-CoA desaturase 1 (SCD1), an enzyme that is involved in the biosynthesis of monounsaturated fatty acids, induces the reprogramming of cardiomyocyte metabolism. Thyroid hormones (THs) activate both lipolysis and lipogenesis. Many genes that are involved in lipid metabolism, including Scd1, are regulated by THs. The present study used SCD1 knockout (SCD1−/−) mice to test the hypothesis that THs are important factors that mediate the anti-steatotic effect of SCD1 downregulation in the heart. SCD1 deficiency decreased plasma levels of thyroid-stimulating hormone and thyroxine and the expression of genes that regulate intracellular TH levels (i.e., Slc16a2 and Dio1-3) in cardiomyocytes. Both hypothyroidism and SCD1 deficiency affected genomic and non-genomic TH pathways in the heart. SCD1 deficiency is known to protect mice from genetic- or diet-induced obesity and decrease lipid content in the heart. Interestingly, hypothyroidism increased body adiposity and triglyceride and diacylglycerol levels in the heart in SCD1−/− mice. The accumulation of triglycerides in cardiomyocytes in SCD1−/− hypothyroid mice was caused by the activation of lipogenesis, which likely exceeded the upregulation of lipolysis and fatty acid oxidation. Lipid accumulation was also observed in the heart in wildtype hypothyroid mice compared with wildtype control mice, but this process was related to a reduction of triglyceride lipolysis and fatty acid oxidation. We also found that simultaneous SCD1 and deiodinase inhibition increased triglyceride content in HL-1 cardiomyocytes, and this process was related to the downregulation of lipolysis. Altogether, the present results suggest that THs are an important part of the mechanism of SCD1 in cardiac lipid utilization and may be involved in the upregulation of energetic metabolism that is associated with SCD1 deficiency.
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Affiliation(s)
- Adam Olichwier
- Laboratory of Molecular Medical Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland; (A.O.); (V.V.B.); (M.W.)
| | - Volodymyr V. Balatskyi
- Laboratory of Molecular Medical Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland; (A.O.); (V.V.B.); (M.W.)
| | - Marcin Wolosiewicz
- Laboratory of Molecular Medical Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland; (A.O.); (V.V.B.); (M.W.)
| | - James M. Ntambi
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA;
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Pawel Dobrzyn
- Laboratory of Molecular Medical Biochemistry, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093 Warsaw, Poland; (A.O.); (V.V.B.); (M.W.)
- Correspondence:
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12
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Xiao Y, Kim M, Lazar MA. Nuclear receptors and transcriptional regulation in non-alcoholic fatty liver disease. Mol Metab 2020; 50:101119. [PMID: 33220489 PMCID: PMC8324695 DOI: 10.1016/j.molmet.2020.101119] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND As a result of a sedentary lifestyle and excess food consumption in modern society, non-alcoholic fatty liver disease (NAFLD) characterized by fat accumulation in the liver is becoming a major disease burden. Non-alcoholic steatohepatitis (NASH) is an advanced form of NAFLD characterized by inflammation and fibrosis that can lead to hepatocellular carcinoma and liver failure. Nuclear receptors (NRs) are a family of ligand-regulated transcription factors that closely control multiple aspects of metabolism. Their transcriptional activity is modulated by various ligands, including hormones and lipids. NRs serve as potential pharmacological targets for NAFLD/NASH and other metabolic diseases. SCOPE OF REVIEW In this review, we provide a comprehensive overview of NRs that have been studied in the context of NAFLD/NASH with a focus on their transcriptional regulation, function in preclinical models, and studies of their clinical utility. MAJOR CONCLUSIONS The transcriptional regulation of NRs is context-dependent. During the dynamic progression of NAFLD/NASH, NRs play diverse roles in multiple organs and different cell types in the liver, which highlights the necessity of targeting NRs in a stage-specific and cell-type-specific manner to enhance the efficacy and safety of treatment methods.
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Affiliation(s)
- Yang Xiao
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mindy Kim
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mitchell A Lazar
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
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Ritter MJ, Amano I, Hollenberg AN. Thyroid Hormone Signaling and the Liver. Hepatology 2020; 72:742-752. [PMID: 32343421 DOI: 10.1002/hep.31296] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/30/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022]
Abstract
Thyroid hormone (TH) plays a critical role in maintaining metabolic homeostasis throughout life. It is well known that the liver and thyroid are intimately linked, with TH playing important roles in de novo lipogenesis, beta-oxidation (fatty acid oxidation), cholesterol metabolism, and carbohydrate metabolism. Indeed, patients with hypothyroidism have abnormal lipid panels with higher levels of low-density lipoprotein levels, triglycerides (triacylglycerol; TAG), and apolipoprotein B levels. Even in euthyroid patients, lower serum-free thyroxine levels are associated with higher total cholesterol levels, LDL, and TAG levels. In addition to abnormal serum lipids, the risk of nonalcoholic fatty liver disease (NAFLD) increases with lower free thyroxine levels. As free thyroxine rises, the risk of NAFLD is reduced. This has led to numerous animal studies and clinical trials investigating TH analogs and TH receptor agonists as potential therapies for NAFLD and hyperlipidemia. Thus, TH plays an important role in maintaining hepatic homeostasis, and this continues to be an important area of study. A review of TH action and TH actions on the liver will be presented here.
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Affiliation(s)
- Megan J Ritter
- Division of Endocrinology, Weill Cornell Medicine, New York, NY
| | - Izuki Amano
- Division of Endocrinology, Weill Cornell Medicine, New York, NY.,Department of Integrative Physiology, Gunma University Graduate School of Medicine, Maebashi, Japan
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Lin X, Liou YH, Li Y, Gong L, Li Y, Hao Y, Pham B, Xu S, Jiang Z, Li L, Peng Y, Qiao D, Lin H, Liu P, Wei W, Zhang G, Lee CH, Zhou X. FAM13A Represses AMPK Activity and Regulates Hepatic Glucose and Lipid Metabolism. iScience 2020; 23:100928. [PMID: 32151973 PMCID: PMC7063182 DOI: 10.1016/j.isci.2020.100928] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/12/2020] [Accepted: 02/17/2020] [Indexed: 12/14/2022] Open
Abstract
Obesity commonly co-exists with fatty liver disease with increasing health burden worldwide. Family with Sequence Similarity 13, Member A (FAM13A) has been associated with lipid levels and fat mass by genome-wide association studies (GWAS). However, the function of FAM13A in maintaining metabolic homeostasis in vivo remains unclear. Here, we demonstrated that rs2276936 in this locus has allelic-enhancer activity in massively parallel reporter assays (MPRA) and reporter assay. The DNA region containing rs2276936 regulates expression of endogenous FAM13A in HepG2 cells. In vivo, Fam13a-/- mice are protected from high-fat diet (HFD)-induced fatty liver accompanied by increased insulin sensitivity and reduced glucose production in liver. Mechanistically, loss of Fam13a led to the activation of AMP-activated protein kinase (AMPK) and increased mitochondrial respiration in primary hepatocytes. These findings demonstrate that FAM13A mediates obesity-related dysregulation of lipid and glucose homeostasis. Targeting FAM13A might be a promising treatment of obesity and fatty liver disease.
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Affiliation(s)
- Xin Lin
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Yae-Huei Liou
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Yujun Li
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Guangzhou First People's Hospital, the Second Affiliated Hospital of South China University of Technology, Guangzhou, Guangdong 510180, China
| | - Lu Gong
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yan Li
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yuan Hao
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Betty Pham
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Shuang Xu
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Zhiqiang Jiang
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Lijia Li
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yifan Peng
- Department of Chemical and Biological Engineering, Tufts University, Boston, MA 02155, USA
| | - Dandi Qiao
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Honghuang Lin
- Section of Computational Biomedicine, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Pengda Liu
- Lineberger Comprehensive Cancer Center and Department of Biochemistry and Biophysics, School of Medicine, The University of North Carolina, Chapel Hill, NC 27514, USA
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Guo Zhang
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Chih-Hao Lee
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Xiaobo Zhou
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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15
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Li Z, Yu Z, Gao P, Yin D. Multigenerational effects of perfluorooctanoic acid on lipid metabolism of Caenorhabditis elegans and its potential mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 703:134762. [PMID: 31761367 DOI: 10.1016/j.scitotenv.2019.134762] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 09/26/2019] [Accepted: 09/29/2019] [Indexed: 05/15/2023]
Abstract
Per-and polyfluoroalkyl substances (PFASs), especially perfluorooctanoic acid (PFOA), have been showed to induce obesogenic effects which may last over generations. However, the underlying mechanisms are not yet clear. In the present study, wild-type N2 Caenorhabditis elegans and the daf-2 mutant were exposed to PFOA for 4 consecutive generations (F0 to F3) at 1.0 ng/L. Effects on fat content and fat metabolism in the directly exposed F0 to F3 generations, the offspring of F0 (T1 to T3) and also those of F3 (T1' to T3'). Results showed that PFOA significantly stimulated the fat contents in F0 (with the percentage of the control as 184.1%), T1 (189.5%), F1 (167.3%), F2 (238.0%), T2' (193.9%) and T3' (159.4%) while inhibited them in T3 (70%). The changes of fat contents over generations were accompanied with significant changes in enzymes facilitating fatty acid synthesis (e.g., acetyl-CoA carboxylase, fatty acid synthase and desaturase, and glycerol phosphate acyltransferase) and those in fatty acid consumption (e.g., acetyl CoA synthetase, fatty acid transport protein, acyl-CoA oxidase and carnitine palmitoyl transferase). Furthermore, RNA-Seq analysis was performed on F0, F3 and T3 generations. Based on the KEGG analysis of differential genes, PFOA exposure affected lipid metabolism signaling pathways including MAPK, fatty acid degradation, TGF-β signaling pathways. Notably, PFOA exposure provoked significantly different effects in daf-2 nematodes on fat contents, lipid metabolizing enzymes and even different signaling pathways. The overall results demonstrated that the obesogenic effects of PFOA were resulted from a complex combination of various enzymes and pathways with essential involvement of insulin signaling pathway.
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Affiliation(s)
- Zhuo Li
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Zhenyang Yu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China; Jiaxing Tongji Institute for Environment, Jiaxing, Zhejiang 314051, PR China.
| | - Pin Gao
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China; College of Environmental Science and Engineering, Donghua University, Shanghai 201620, PR China
| | - Daqiang Yin
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
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16
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Sinha RA, Bruinstroop E, Singh BK, Yen PM. Nonalcoholic Fatty Liver Disease and Hypercholesterolemia: Roles of Thyroid Hormones, Metabolites, and Agonists. Thyroid 2019; 29:1173-1191. [PMID: 31389309 PMCID: PMC6850905 DOI: 10.1089/thy.2018.0664] [Citation(s) in RCA: 136] [Impact Index Per Article: 27.2] [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
Background: Thyroid hormones (THs) exert a strong influence on mammalian lipid metabolism at the systemic and hepatic levels by virtue of their roles in regulating circulating lipoprotein, triglyceride (TAG), and cholesterol levels, as well as hepatic TAG storage and metabolism. These effects are mediated by intricate sensing and feedback systems that function at the physiological, metabolic, molecular, and transcriptional levels in the liver. Dysfunction in the pathways involved in lipid metabolism disrupts hepatic lipid homeostasis and contributes to the pathogenesis of metabolic diseases, such as nonalcoholic fatty liver disease (NAFLD) and hypercholesterolemia. There has been strong interest in understanding and employing THs, TH metabolites, and TH mimetics as lipid-modifying drugs. Summary: THs regulate many processes involved in hepatic TAG and cholesterol metabolism to decrease serum cholesterol and intrahepatic lipid content. TH receptor β analogs designed to have less side effects than the natural hormone are currently being tested in phase II clinical studies for NAFLD and hypercholesterolemia. The TH metabolites, 3,5-diiodo-l-thyronine (T2) and T1AM (3-iodothyronamine), have different beneficial effects on lipid metabolism compared with triiodothyronine (T3), although their clinical application is still under investigation. Also, prodrugs and glucagon/T3 conjugates have been developed that direct TH to the liver. Conclusions: TH-based therapies show clinical promise for the treatment of NAFLD and hypercholesterolemia. Strategies for limiting side effects of TH are being developed and may enable TH metabolites and analogs to have specific effects in the liver for treatments of these conditions. These liver-specific effects and potential suppression of the hypothalamic/pituitary/thyroid axis raise the issue of monitoring liver-specific markers of TH action to assess clinical efficacy and dosing of these compounds.
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Affiliation(s)
- Rohit A. Sinha
- Department of Endocrinology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India
| | - Eveline Bruinstroop
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Endocrinology & Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Brijesh K. Singh
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore, Singapore
| | - Paul M. Yen
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore, Singapore
- Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, North Carolina
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17
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Gionfra F, De Vito P, Pallottini V, Lin HY, Davis PJ, Pedersen JZ, Incerpi S. The Role of Thyroid Hormones in Hepatocyte Proliferation and Liver Cancer. Front Endocrinol (Lausanne) 2019; 10:532. [PMID: 31543862 PMCID: PMC6730500 DOI: 10.3389/fendo.2019.00532] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/17/2019] [Indexed: 12/13/2022] Open
Abstract
Thyroid hormones T3 and T4 (thyroxine) control a wide variety of effects related to development, differentiation, growth and metabolism, through their interaction with nuclear receptors. But thyroid hormones also produce non-genomic effects that typically start at the plasma membrane and are mediated mainly by integrin αvβ3, although other receptors such as TRα and TRβ are also able to elicit non-genomic responses. In the liver, the effects of thyroid hormones appear to be particularly important. The liver is able to regenerate, but it is subject to pathologies that may lead to cancer, such as fibrosis, cirrhosis, and non-alcoholic fatty liver disease. In addition, cancer cells undergo a reprogramming of their metabolism, resulting in drastic changes such as aerobic glycolysis instead of oxidative phosphorylation. As a consequence, the pyruvate kinase isoform M2, the rate-limiting enzyme of glycolysis, is dysregulated, and this is considered an important factor in tumorigenesis. Redox equilibrium is also important, in fact cancer cells give rise to the production of more reactive oxygen species (ROS) than normal cells. This increase may favor the survival and propagation of cancer cells. We evaluate the possible mechanisms involving the plasma membrane receptor integrin αvβ3 that may lead to cancer progression. Studying diseases that affect the liver and their experimental models may help to unravel the cellular pathways mediated by integrin αvβ3 that can lead to liver cancer. Inhibitors of integrin αvβ3 might represent a future therapeutic tool against liver cancer. We also include information on the possible role of exosomes in liver cancer, as well as on recent strategies such as organoids and spheroids, which may provide a new tool for research, drug discovery, and personalized medicine.
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Affiliation(s)
- Fabio Gionfra
- Department of Sciences, University Roma Tre, Rome, Italy
| | - Paolo De Vito
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | | | - Hung-Yun Lin
- Ph.D. Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Taipei Cancer Center, Taipei Medical University, Taipei, Taiwan
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, United States
- Traditional Herbal Medicine Research Center of Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan
- Department of Medicine, Albany Medical College, Albany, NY, United States
| | - Paul J. Davis
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, United States
- Department of Medicine, Albany Medical College, Albany, NY, United States
| | - Jens Z. Pedersen
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Sandra Incerpi
- Department of Sciences, University Roma Tre, Rome, Italy
- *Correspondence: Sandra Incerpi
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18
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Abstract
It has been known for a long time that thyroid hormones have prominent effects on hepatic fatty acid and cholesterol synthesis and metabolism. Indeed, hypothyroidism has been associated with increased serum levels of triglycerides and cholesterol as well as non-alcoholic fatty liver disease (NAFLD). Advances in areas such as cell imaging, autophagy and metabolomics have generated a more detailed and comprehensive picture of thyroid-hormone-mediated regulation of hepatic lipid metabolism at the molecular level. In this Review, we describe and summarize the key features of direct thyroid hormone regulation of lipogenesis, fatty acid β-oxidation, cholesterol synthesis and the reverse cholesterol transport pathway in normal and altered thyroid hormone states. Thyroid hormone mediates these effects at the transcriptional and post-translational levels and via autophagy. Given these potentially beneficial effects on lipid metabolism, it is possible that thyroid hormone analogues and/or mimetics might be useful for the treatment of metabolic diseases involving the liver, such as hypercholesterolaemia and NAFLD.
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Affiliation(s)
- Rohit A. Sinha
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Programme, Duke-NUS Medical School, Singapore, Singapore
- Department of Endocrinology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
- ;
| | - Brijesh K. Singh
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Paul M. Yen
- Laboratory of Hormonal Regulation, Cardiovascular and Metabolic Disorders Programme, Duke-NUS Medical School, Singapore, Singapore
- ;
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19
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Jia Y, Yee JK, Wang C, Nikolaenko L, Diaz-Arjonilla M, Cohen JN, French SW, Liu PY, Lue Y, Lee WNP, Swerdloff RS. Testosterone protects high-fat/low-carbohydrate diet-induced nonalcoholic fatty liver disease in castrated male rats mainly via modulating endoplasmic reticulum stress. Am J Physiol Endocrinol Metab 2018; 314:E366-E376. [PMID: 28928235 PMCID: PMC5966753 DOI: 10.1152/ajpendo.00124.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We previously showed that testosterone (T) deficiency enhanced high-fat/low-carbohydrate diet (HFD)-induced hepatic steatosis in rats independent of insulin resistance and that T replacement reduced hepatic macrovesicular fat accumulation and inflammation. The present report explores the mechanism of T's protective effects on HFD-induced steatohepatitis. Adult male rats were randomized into four treatment groups for 15 wk: intact rats on regular chow diet or HFD, and castrated rats on HFD with or without T replacement. Fatty acid β-oxidation and de novo synthesis were not changed by castration and T replacement, but expression of lipid export proteins ApoB100 and microsomal triglyceride transfer protein (MTP) was suppressed by HFD in both intact and castrated rats but restored by T replacement. Macrovesicular lipid droplet-related proteins perilipin 1 and fat-specific protein 27 were increased by HFD in castrated rats and suppressed by T replacement. Higher activation/expression of ER stress proteins (PERK, IRE-1α, JNK, NF-κB, and CHOP) was demonstrated in castrated rats fed HFD compared with intact animals, and T replacement suppressed these changes. We conclude that 1) HFD leads to ApoB100/MTP suppression reducing export of lipids; 2) castration promotes progression to steatohepatitis through activation of the ER stress pathway and enhancement of macrovesicular droplet protein expression; and 3) testosterone suppresses ER stress, inhibits the formation of macrovesicular lipid droplets, promotes lipid export, and ameliorates steatohepatitis induced by HFD and castration.
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Affiliation(s)
- Yue Jia
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Jennifer K Yee
- Department and Endocrinology, Department of Pediatrics, Harbor-UCLA Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Christina Wang
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Liana Nikolaenko
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Maruja Diaz-Arjonilla
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Joshua N Cohen
- Department and Endocrinology, Department of Pediatrics, Harbor-UCLA Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Samuel W French
- Department of Pathology, Harbor-UCLA Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Peter Y Liu
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - YanHe Lue
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Wai-Nang P Lee
- Department and Endocrinology, Department of Pediatrics, Harbor-UCLA Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
| | - Ronald S Swerdloff
- Division of Endocrinology, Department of Medicine, Harbor-University of California, Los Angeles (UCLA), Medical Center , Torrance, California
- Department of Pathology, Harbor-UCLA Medical Center , Torrance, California
- Los Angeles Biomedical Research Institute , Torrance, California
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20
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Senese R, Cioffi F, de Lange P, Leanza C, Iannucci LF, Silvestri E, Moreno M, Lombardi A, Goglia F, Lanni A. Both 3,5-Diiodo-L-Thyronine and 3,5,3'-Triiodo-L-Thyronine Prevent Short-term Hepatic Lipid Accumulation via Distinct Mechanisms in Rats Being Fed a High-Fat Diet. Front Physiol 2017; 8:706. [PMID: 28959215 PMCID: PMC5603695 DOI: 10.3389/fphys.2017.00706] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/31/2017] [Indexed: 12/14/2022] Open
Abstract
3,3′,5-triiodo-L-thyronine (T3) improves hepatic lipid accumulation by increasing lipid catabolism but it also increases lipogenesis, which at first glance appears contradictory. Recent studies have shown that 3,5-diiodothyronine (T2), a natural thyroid hormone derivative, also has the capacity to stimulate hepatic lipid catabolism, however, little is known about its possible effects on lipogenic gene expression. Because genes classically involved in hepatic lipogenesis such as SPOT14, acetyl-CoA-carboxylase (ACC), and fatty acid synthase (FAS) contain thyroid hormone response elements (TREs), we studied their transcriptional regulation, focusing on TRE-mediated effects of T3 compared to T2 in rats receiving high-fat diet (HFD) for 1 week. HFD rats showed a marked lipid accumulation in the liver, which was significantly reduced upon simultaneous administration of either T3 or T2 with the diet. When administered to HFD rats, T2, in contrast with T3, markedly downregulated the expression of the above-mentioned genes. T2 downregulated expression of the transcription factors carbohydrate-response element-binding protein (ChREBP) and sterol regulatory element binding protein-1c (SREBP-1c) involved in activation of transcription of these genes, which explains the suppressed expression of their target genes involved in lipogenesis. T3, however, did not repress expression of the TRE-containing ChREBP gene but repressed SREBP-1c expression. Despite suppression of SREBP-1c expression by T3 (which can be explained by the presence of nTRE in its promoter), the target genes were not suppressed, but normalized to HFD reference levels or even upregulated (ACC), partly due to the presence of TREs on the promoters of these genes and partly to the lack of suppression of ChREBP. Thus, T2 and T3 probably act by different molecular mechanisms to achieve inhibition of hepatic lipid accumulation.
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Affiliation(s)
- Rosalba Senese
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania, "Luigi Vanvitelli" CasertaCaserta, Italy
| | - Federica Cioffi
- Dipartimento di Scienze e Tecnologie, Università degli Studi del SannioBenevento, Italy
| | - Pieter de Lange
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania, "Luigi Vanvitelli" CasertaCaserta, Italy
| | - Cristina Leanza
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania, "Luigi Vanvitelli" CasertaCaserta, Italy
| | - Liliana F Iannucci
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania, "Luigi Vanvitelli" CasertaCaserta, Italy
| | - Elena Silvestri
- Dipartimento di Scienze e Tecnologie, Università degli Studi del SannioBenevento, Italy
| | - Maria Moreno
- Dipartimento di Scienze e Tecnologie, Università degli Studi del SannioBenevento, Italy
| | - Assunta Lombardi
- Dipartimento di Biologia, Università degli Studi di Napoli Federico IINaples, Italy
| | - Fernando Goglia
- Dipartimento di Scienze e Tecnologie, Università degli Studi del SannioBenevento, Italy
| | - Antonia Lanni
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania, "Luigi Vanvitelli" CasertaCaserta, Italy
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21
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Damiano F, Rochira A, Gnoni A, Siculella L. Action of Thyroid Hormones, T3 and T2, on Hepatic Fatty Acids: Differences in Metabolic Effects and Molecular Mechanisms. Int J Mol Sci 2017; 18:ijms18040744. [PMID: 28362337 PMCID: PMC5412329 DOI: 10.3390/ijms18040744] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 03/22/2017] [Accepted: 03/27/2017] [Indexed: 12/28/2022] Open
Abstract
The thyroid hormones (THs) 3,3′,5,5′-tetraiodo-l-thyronine (T4) and 3,5,3′-triiodo-l-thyronine (T3) influence many metabolic pathways. The major physiological function of THs is to sustain basal energy expenditure, by acting primarily on carbohydrate and lipid catabolism. Beyond the mobilization and degradation of lipids, at the hepatic level THs stimulate the de novo fatty acid synthesis (de novo lipogenesis, DNL), through both the modulation of gene expression and the rapid activation of cell signalling pathways. 3,5-Diiodo-l-thyronine (T2), previously considered only a T3 catabolite, has been shown to mimic some of T3 effects on lipid catabolism. However, T2 action is more rapid than that of T3, and seems to be independent of protein synthesis. An inhibitory effect on DNL has been documented for T2. Here, we give an overview of the mechanisms of THs action on liver fatty acid metabolism, focusing on the different effects exerted by T2 and T3 on the regulation of the DNL. The inhibitory action on DNL exerted by T2 makes this compound a potential and attractive drug for the treatment of some metabolic diseases and cancer.
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Affiliation(s)
- Fabrizio Damiano
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy.
| | - Alessio Rochira
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy.
| | - Antonio Gnoni
- Department of Basic Medical Sciences, Section of Medical Biochemistry, University of Bari Aldo Moro, 70125 Bari, Italy.
| | - Luisa Siculella
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy.
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22
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Mandave P, Khadke S, Karandikar M, Pandit V, Ranjekar P, Kuvalekar A, Mantri N. Antidiabetic, Lipid Normalizing, and Nephroprotective Actions of the Strawberry: A Potent Supplementary Fruit. Int J Mol Sci 2017; 18:E124. [PMID: 28085064 PMCID: PMC5297758 DOI: 10.3390/ijms18010124] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 12/24/2016] [Accepted: 12/28/2016] [Indexed: 12/15/2022] Open
Abstract
The study was designed to assess the effect of different strawberry extracts on glucose levels, lipid profiles, and oxidative stress in nicotinamide-streptozotocin (NIC-STZ) induced diabetic rats. The associated changes were evaluated through biochemical, molecular, and histological assays. Diabetes was induced by intraperitoneal injection of STZ to albino Wistar rats after treatment with nicotinamide. Aqueous, hydroalcoholic, and alcoholic strawberry extracts were administrated orally to diabetic rats. Treatment of strawberry extracts improved lipid profile, liver function, and serum creatinine and led to a significant increase in antioxidant status in diabetic rats. Real-time PCR expression analysis of genes from the liver of animals treated with strawberry extracts exhibited downregulation of several fatty acid synthesis genes, transcription factors, such as Sterol regulatory Element Binding Transcription factor (SREBP) and Nuclear Factor-κβ (NF-κβ), and inflammatory markers, like Interleukin 6 (IL6) and Tumor Necrosis Factor-α (TNF-α). Strawberry extracts also upregulated liver Peroxisome Proliferator Activated Receptor-γ (PPAR-γ). Histological examination confirmed the nephroprotective and β-cell regeneration/protection effects of strawberry extracts. The present study demonstrates several beneficial effects of strawberry extracts along with its probable mechanism of action.
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Affiliation(s)
- Pallavi Mandave
- Interactive Research School for Health Affairs, Bharati Vidyapeeth University, Katraj, Pune, Maharashtra 411043, India.
| | - Suresh Khadke
- Interactive Research School for Health Affairs, Bharati Vidyapeeth University, Katraj, Pune, Maharashtra 411043, India.
| | - Manjiri Karandikar
- Department of Pathology, Bharati Vidyapeeth Medical College, Bharati Vidyapeeth Deemed University, Pune-Satara Road, Pune, Maharashtra 411043, India.
| | - Vijaya Pandit
- Department of Pharmacology, Bharati Vidyapeeth Medical College, Bharati Vidyapeeth Deemed University, Pune-Satara Road, Pune, Maharashtra 411043, India.
| | - Prabhakar Ranjekar
- Interactive Research School for Health Affairs, Bharati Vidyapeeth University, Katraj, Pune, Maharashtra 411043, India.
| | - Aniket Kuvalekar
- Interactive Research School for Health Affairs, Bharati Vidyapeeth University, Katraj, Pune, Maharashtra 411043, India.
| | - Nitin Mantri
- School of Science, RMIT University, Melbourne 3000, Australia.
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23
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Singh SB, Kang L, Nawrocki AR, Zhou D, Wu M, Previs S, Miller C, Liu H, Hines CDG, Madeira M, Cao J, Herath K, Wang L, Kelley DE, Li C, Guan HP. The Fatty Acid Synthase Inhibitor Platensimycin Improves Insulin Resistance without Inducing Liver Steatosis in Mice and Monkeys. PLoS One 2016; 11:e0164133. [PMID: 27695056 PMCID: PMC5047649 DOI: 10.1371/journal.pone.0164133] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 09/20/2016] [Indexed: 01/12/2023] Open
Abstract
Objectives Platensimycin (PTM) is a natural antibiotic produced by Streptomyces platensis that selectively inhibits bacterial and mammalian fatty acid synthase (FAS) without affecting synthesis of other lipids. Recently, we reported that oral administration of PTM in mouse models (db/db and db/+) with high de novo lipogenesis (DNL) tone inhibited DNL and enhanced glucose oxidation, which in turn led to net reduction of liver triglycerides (TG), reduced ambient glucose, and improved insulin sensitivity. The present study was conducted to explore translatability and the therapeutic potential of FAS inhibition for the treatment of diabetes in humans. Methods We tested PTM in animal models with different DNL tones, i.e. intrinsic synthesis rates, which vary among species and are regulated by nutritional and disease states, and confirmed glucose-lowering efficacy of PTM in lean NHPs with quantitation of liver lipid by MRS imaging. To understand the direct effect of PTM on liver metabolism, we performed ex vivo liver perfusion study to compare FAS inhibitor and carnitine palmitoyltransferase 1 (CPT1) inhibitor. Results The efficacy of PTM is generally reproduced in preclinical models with DNL tones comparable to humans, including lean and established diet-induced obese (eDIO) mice as well as non-human primates (NHPs). Similar effects of PTM on DNL reduction were observed in lean and type 2 diabetic rhesus and lean cynomolgus monkeys after acute and chronic treatment of PTM. Mechanistically, PTM lowers plasma glucose in part by enhancing hepatic glucose uptake and glycolysis. Teglicar, a CPT1 inhibitor, has similar effects on glucose uptake and glycolysis. In sharp contrast, Teglicar but not PTM significantly increased hepatic TG production, thus caused liver steatosis in eDIO mice. Conclusions These findings demonstrate unique properties of PTM and provide proof-of-concept of FAS inhibition having potential utility for the treatment of diabetes and related metabolic disorders.
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Affiliation(s)
- Sheo B. Singh
- Departments of Discovery Chemistry, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
- * E-mail: (SBS); (HPG)
| | - Ling Kang
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Andrea R. Nawrocki
- Department of Pharmacology, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Dan Zhou
- Department of Pharmacology, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Margaret Wu
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Stephen Previs
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Corey Miller
- Department of Imaging and Biomarker, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Haiying Liu
- Department of Imaging and Biomarker, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Catherine D. G. Hines
- Department of Translational Imaging Biomarkers, Merck Research Laboratories, 770 Sumneytown Pike, West Point, PA, 19486, United States of America
| | - Maria Madeira
- Department of PKPD, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Jin Cao
- Department of Imaging and Biomarker, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Kithsiri Herath
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Liangsu Wang
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - David E. Kelley
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Cai Li
- Department of Pharmacology, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
| | - Hong-Ping Guan
- Department of Cardiometabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Rd, Kenilworth, NJ, 07033, United States of America
- * E-mail: (SBS); (HPG)
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24
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Gambo Y, Matsumura M, Fujimori K. Triiodothyronine enhances accumulation of intracellular lipids in adipocytes through thyroid hormone receptor α via direct and indirect mechanisms. Mol Cell Endocrinol 2016; 431:1-11. [PMID: 27132806 DOI: 10.1016/j.mce.2016.04.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 01/16/2023]
Abstract
Triiodothyronine (T3) enhanced the expression of adipogenic and lipogenic genes with elevation of the intracellular lipids through thyroid hormone receptor (TR) α in mouse 3T3-L1 cells. However, the transcription of the SREBP-1c and HSL genes was decreased by T3. Such T3-mediated alterations were negated by TRα siRNA. Chromatin immunoprecipitation assay showed that the binding of TRα to the TR-responsive element (TRE) of the FAS promoter was elevated by T3. In contrast, the ability of TRα to bind to the TRE of the SREBP-1c promoter was decreased by T3. In addition, the binding of SREBP-1c to the SRE of the HSL promoter was lowered by T3. These results indicate that T3 increased the accumulation of intracellular lipids by enhancing the expression of the FAS gene through direct binding of TRα to the FAS promoter and simultaneously lowered the amount of lipolysis via reduced binding of T3-decreased SREBP-1c to the HSL promoter.
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Affiliation(s)
- Yurina Gambo
- Laboratory of Biodefense and Regulation, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Miki Matsumura
- Laboratory of Biodefense and Regulation, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Ko Fujimori
- Laboratory of Biodefense and Regulation, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
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25
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Giudetti AM, Stanca E, Siculella L, Gnoni GV, Damiano F. Nutritional and Hormonal Regulation of Citrate and Carnitine/Acylcarnitine Transporters: Two Mitochondrial Carriers Involved in Fatty Acid Metabolism. Int J Mol Sci 2016; 17:ijms17060817. [PMID: 27231907 PMCID: PMC4926351 DOI: 10.3390/ijms17060817] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/06/2016] [Accepted: 05/19/2016] [Indexed: 12/13/2022] Open
Abstract
The transport of solutes across the inner mitochondrial membrane is catalyzed by a family of nuclear-encoded membrane-embedded proteins called mitochondrial carriers (MCs). The citrate carrier (CiC) and the carnitine/acylcarnitine transporter (CACT) are two members of the MCs family involved in fatty acid metabolism. By conveying acetyl-coenzyme A, in the form of citrate, from the mitochondria to the cytosol, CiC contributes to fatty acid and cholesterol synthesis; CACT allows fatty acid oxidation, transporting cytosolic fatty acids, in the form of acylcarnitines, into the mitochondrial matrix. Fatty acid synthesis and oxidation are inversely regulated so that when fatty acid synthesis is activated, the catabolism of fatty acids is turned-off. Malonyl-CoA, produced by acetyl-coenzyme A carboxylase, a key enzyme of cytosolic fatty acid synthesis, represents a regulator of both metabolic pathways. CiC and CACT activity and expression are regulated by different nutritional and hormonal conditions. Defects in the corresponding genes have been directly linked to various human diseases. This review will assess the current understanding of CiC and CACT regulation; underlining their roles in physio-pathological conditions. Emphasis will be placed on the molecular basis of the regulation of CiC and CACT associated with fatty acid metabolism.
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Affiliation(s)
- Anna M Giudetti
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce 73100, Italy.
| | - Eleonora Stanca
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce 73100, Italy.
| | - Luisa Siculella
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce 73100, Italy.
| | - Gabriele V Gnoni
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce 73100, Italy.
| | - Fabrizio Damiano
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce 73100, Italy.
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26
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Martin J, Balmer ML, Rajendran S, Maurhofer O, Dufour JF, St-Pierre MV. Nutritional stress exacerbates hepatic steatosis induced by deletion of the histidine nucleotide-binding (Hint2) mitochondrial protein. Am J Physiol Gastrointest Liver Physiol 2016; 310:G497-509. [PMID: 26767982 DOI: 10.1152/ajpgi.00178.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 01/07/2016] [Indexed: 01/31/2023]
Abstract
The histidine nucleotide-binding protein, Hint2, is a mitochondrial phosphoramidase expressed in liver, brown fat, pancreas, and muscle. The livers of Hint2 knockout (Hint2(-/-)) mice accumulate triglycerides and show a pattern of mitochondrial protein lysine hyperacetylation. The extent and nature of the lysine acetylation changes and the response of Hint2(-/-) mice to nutritional challenges that elicit a modification of protein acetylation have not been investigated. To compare the adaptation of Hint2(-/-) and control (Hint2(+/+)) mice with episodes of fasting and high-fat diet (HFD), we subjected animals to either feeding ad libitum or fasting for 24 h, and to either a HFD or control diet for 8 wk. Triglyceride content was higher in Hint2(-/-) than in Hint2(+/+) livers, whereas plasma triglycerides were fourfold lower. Malonyl-CoA levels were increased twofold in Hint2(-/-) livers. After 24 h fasting, Hint2(-/-) displayed a decrease in body temperature, commensurate with a decrease in mass of brown fat and downregulation of uncoupling protein 1. HFD-treated Hint2(-/-) livers showed more steatosis, and plasma insulin and cholesterol were higher than in Hint(+/+) mice. Several proteins identified as substrates of sirtuin 3 and 5 and active in intermediary and ketone metabolism were hyperacetylated in liver and brown fat mitochondria after both HFD and fasting regimens. Glutamate dehydrogenase activity was downregulated in fed and fasted livers, and this was attributed to an increase in acetylation and ADP-ribosylation. The absence of Hint2 deregulates the posttranslational modification of several mitochondrial proteins, which impedes the adaptation to episodes of nutritional stress.
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Affiliation(s)
- Juliette Martin
- Department of Clinical Research, University of Bern, Bern, Switzerland; and Department of Hepatology, Gastroenterology; and
| | - Maria L Balmer
- Department of Clinical Research, University of Bern, Bern, Switzerland; and Department of Hepatology, Gastroenterology; and
| | - Saranya Rajendran
- Department of Clinical Research, University of Bern, Bern, Switzerland; and Department of Hepatology, Gastroenterology; and
| | - Olivier Maurhofer
- Department of Clinical Research, University of Bern, Bern, Switzerland; and Department of Hepatology, Gastroenterology; and
| | - Jean-François Dufour
- Department of Clinical Research, University of Bern, Bern, Switzerland; and Department of Hepatology, Gastroenterology; and Visceral Surgery, University Hospital, Inselspital, Bern, Switzerland
| | - Marie V St-Pierre
- Department of Clinical Research, University of Bern, Bern, Switzerland; and Department of Hepatology, Gastroenterology; and
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27
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Gebhardt R. Speeding up hepatocyte proliferation: how triiodothyronine and β-catenin join forces. Hepatology 2014; 59:2074-6. [PMID: 24919451 DOI: 10.1002/hep.26984] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 12/15/2013] [Indexed: 01/20/2023]
Affiliation(s)
- Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany
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28
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Zhang D, Lu K, Dong Z, Jiang G, Xu W, Liu W. The effect of exposure to a high-fat diet on microRNA expression in the liver of blunt snout bream (Megalobrama amblycephala). PLoS One 2014; 9:e96132. [PMID: 24788396 PMCID: PMC4008502 DOI: 10.1371/journal.pone.0096132] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 04/02/2014] [Indexed: 12/15/2022] Open
Abstract
Blunt snout bream (Megalobrama amblycephala) are susceptible to hepatic steatosis when maintained in modern intensive culture systems. The aim of this study was to investigate the potential roles of microRNAs (miRNAs) in diet-induced hepatic steatosis in this species. MiRNAs, small non-coding RNAs that regulate gene expression at the posttranscriptional level, are involved in diverse biological processes, including lipid metabolism. Deep sequencing of hepatic small RNA libraries from blunt snout bream fed normal-fat and high-fat diets identified 202 (193 known and 9 novel) miRNAs, of which 12 were differentially expressed between the normal-fat and high-fat diet groups. Quantitative stem-loop reverse transcriptase-polymerase chain reaction analyses confirmed the upregulation of miR-30c and miR-30e-3p and the downregulation of miR-145 and miR-15a-5p in high-fat diet-fed fish. Bioinformatics tools were used to predict the targets of these verified miRNAs and to explore potential downstream gene ontology biological process categories and Kyoto Encyclopedia of Genes and Genomes pathways. Six putative lipid metabolism-related target genes (fetuin-B, Cyp7a1, NADH dehydrogenase (ubiquinone) 1 beta subcomplex subunit 2, 3-oxoacid CoA transferase 1b, stearoyl-CoA desaturase, and fatty-acid synthase) were identified as having potential important roles in the development of diet-induced hepatic steatosis in blunt snout bream. The results presented here are a foundation for future studies of miRNA-controlled lipid metabolism regulatory networks in blunt snout bream.
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Affiliation(s)
- Dingdong Zhang
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Kangle Lu
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Zaijie Dong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
- * E-mail: (WL); (ZD)
| | - Guangzhen Jiang
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Weina Xu
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Wenbin Liu
- Key Laboratory of Aquatic Nutrition and Feed Science of Jiangsu Province, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
- * E-mail: (WL); (ZD)
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29
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Suppression of adipogenesis by valproic acid through repression of USF1-activated fatty acid synthesis in adipocytes. Biochem J 2014; 459:489-503. [DOI: 10.1042/bj20131476] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Valproic acid suppresses the accumulation of the intracellular lipids through suppression of fatty acid synthesis via repression of USF1-mediated expression of the fatty acid synthase gene in adipocytes.
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30
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Nikolaenko L, Jia Y, Wang C, Diaz-Arjonilla M, Yee JK, French SW, Liu PY, Laurel S, Chong C, Lee K, Lue Y, Lee WNP, Swerdloff RS. Testosterone replacement ameliorates nonalcoholic fatty liver disease in castrated male rats. Endocrinology 2014; 155:417-28. [PMID: 24280056 PMCID: PMC5393315 DOI: 10.1210/en.2013-1648] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Nonalcoholic fatty liver disease is common in developed countries and is associated with obesity, metabolic syndrome, and type 2 diabetes. T deficiency is a risk factor for developing these metabolic deficiencies, but its role in hepatic steatosis has not been well studied. We investigated the effects of T on the pathogenesis of hepatic steatosis in rats fed a high-fat diet (HFD). Adult male rats were randomly placed into four groups and treated for 15 weeks: intact rats on regular chow diet (RCD), intact rats on liquid HFD (I+HFD), castrated rats on HFD (C+HFD), and castrated rats with T replacement on HFD (C+HFD+T). Fat contributed 71% energy to the HFD but only 16% of energy to the RCD. Serum T level was undetectable in castrated rats, and T replacement led to 2-fold higher mean serum T levels than in intact rats. C+HFD rats gained less weight but had higher percentage body fat than C+HFD+T. Severe micro- and macrovesicular fat accumulated in hepatocytes with multiple inflammatory foci in the livers of C+HFD. I+HFD and C+HFD+T hepatocytes demonstrated only mild to moderate microvesicular steatosis. T replacement attenuated HFD-induced hepatocyte apoptosis in castrated rats. Serum glucose and insulin levels were not increased with HFD in any group. Immunoblots showed that insulin-regulated proteins were not changed in any group. This study demonstrates that T deficiency may contribute to the severity of hepatic steatosis and T may play a protective role in hepatic steatosis and nonalcoholic fatty liver disease development without insulin resistance.
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Affiliation(s)
- L Nikolaenko
- Divisions of Endocrinology, Departments of Medicine (L.N., Y.J., C.W., M.D.-A., P.Y.L., S.L., C.C., K.L., Y.L., R.S.S.) and Pediatrics (J.K.Y., W.N.P.L.), and Department of Pathology (S.W.F.) Harbor-UCLA Medical Center and Los Angeles Biomedical Research Institute, Torrance, California 90509
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Blanco J, Mulero M, Domingo JL, Sanchez DJ. Perinatal exposure to BDE-99 causes decreased protein levels of cyclin D1 via GSK3β activation and increased ROS production in rat pup livers. Toxicol Sci 2013; 137:491-8. [PMID: 24218147 DOI: 10.1093/toxsci/kft257] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We here examined the potential liver toxicity in rat pups from dams exposed during the gestational and lactation periods to 2,2',4,4',5-pentabromodiphenyl ether (BDE-99). Dams were exposed to 0, 1, and 2mg/kg/day of BDE-99 from gestation day 6 to postnatal day 21. When the pups were weaning, the liver from 1 pup of each litter was excised to evaluate oxidative stress markers and the messenger RNA (mRNA) expression of multiple cytochrome P450 (CYP) isoforms. To determine whether thyroid hormone (TH) was disrupted, the protein and mRNA expressions of several TH receptor (TR) isoforms, as well as the protein levels of cyclin D1 and the phosphorylated protein kinases Akt and glycogen synthase kinase 3 beta (GSK3β), were evaluated. Perinatal exposure to BDE-99 produced decreased levels of cyclin D1 in rat pup livers. A decrease in the active form of Akt and an increase in the active form of GSK3β were observed. The decreased Akt pathway may be due to a potential disruption of the nongenomic actions of TH by BDE-99 and its metabolites. This possible TH disruption was noted as a decrease in TR isoforms expression. By contrast, we observed an upregulation of CYP2B1 gene expression, which is correlated with an increase in reactive oxygen species production. This outcome indicates activation of the nuclear constitutive androstane receptor, which could induce the expression of other enzymes capable of metabolizing TH. The present findings support the hypothesis that perinatal exposure to PBDEs, at levels found in humans, may have serious implications for metabolic processes in rat pup livers.
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Affiliation(s)
- Jordi Blanco
- * Laboratory of Toxicology and Environmental Health and
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Inafuku M, Nugara RN, Kamiyama Y, Futenma I, Inafuku A, Oku H. Cirsium brevicaule A. GRAY leaf inhibits adipogenesis in 3T3-L1 cells and C57BL/6 mice. Lipids Health Dis 2013; 12:124. [PMID: 23945333 PMCID: PMC3751477 DOI: 10.1186/1476-511x-12-124] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 08/14/2013] [Indexed: 01/01/2023] Open
Abstract
Background Various flavonoids obtained from the genus Cirsium have been reported to exhibit beneficial effects on health. The present study evaluated the antiobesity effects of Cirsium brevicaule A. GRAY leaf (CL) by using 3T3-L1 cells and C57BL/6 mice that were fed a high-fat diet (HFD). Methods Dried CL powder was serially extracted with solvents of various polarities, and these extracts were tested for antiadipogenic activity using 3T3-L1 adipocytes. Mice were fed experimental HFD supplemented with dried CL powder for 4 wk. Lipid levels and mRNA levels of genes related to lipid metabolism were determined in 3T3-L1 adipocytes and the white adipose tissue (WAT) and liver of mice fed on a HFD. Results Treatment of 3T3-L1 adipocytes with a hexane extract of CL significantly reduced cellular lipid accumulation and expression of the fatty acid synthase (FASN) gene. Dietary CL reduced the serum levels of non-esterified fatty acids in HFD-fed mice. Significant decreases in subcutaneous WAT weight and associated FASN gene expression were observed in the mice fed the experimental CL diet. Dietary CL also reduced the hepatic lipid and serum levels of a hepatopathic indicator in the HFD-fed mice. A significant reduction in mRNA levels of FASN and HMG-CoA reductase were observed in the livers of the CL-diet group. Dietary CL, on the other hand, increased in the hepatic mRNA levels of genes related to β-oxidation, namely peroxisome proliferator-activated receptor α, calnitine palmitoyltrasferase 1A, and uncoupling protein 2. Expression of the insulin receptor gene was also significantly increased in the livers of mice-fed the CL diet. Conclusions The present study therefore demonstrated that CL suppresses lipid accumulation in the WAT and liver partly through inhibiting mRNA levels of FASN gene and enhancing the lipolysis-related gene expression.
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Affiliation(s)
- Masashi Inafuku
- Center of Molecular Biosciences, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan
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Cordeiro A, Souza LL, Einicker-Lamas M, Pazos-Moura CC. Non-classic thyroid hormone signalling involved in hepatic lipid metabolism. J Endocrinol 2013; 216:R47-57. [PMID: 23297113 DOI: 10.1530/joe-12-0542] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Thyroid hormones are important modulators of lipid metabolism because the liver is a primary hormonal target. The hypolipidaemic effects of thyroid hormones result from the balance between direct and indirect actions resulting in stimulation of lipid synthesis and lipid oxidation, which favours degradation pathways. Originally, it was believed that thyroid hormone activity was only transduced by alteration of gene transcription mediated by the nuclear receptor thyroid hormone receptors, comprising the classic action of thyroid hormone. However, the discovery of other effects independent of this classic mechanism characterised a new model of thyroid hormone action, the non-classic mechanism that involves other signalling pathways. To date, this mechanism and its relevance have been intensively described. Considering the increasing evidence for non-classic signalling of thyroid hormones and the major influence of these hormones in the regulation of lipid metabolism, we reviewed the role of thyroid hormone in cytosolic signalling cascades, focusing on the regulation of second messengers, and the activity of effector proteins and the implication of these mechanisms on the control of hepatic lipid metabolism.
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Affiliation(s)
- Aline Cordeiro
- Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Centro de Ciências da Saúde, Avenida Carlos Chagas Filho, 373, Bloco G, Cidade Universitária - Ilha do Fundão, Rio de Janeiro - RJ 21941-902, Brazil.
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Gathercole LL, Morgan SA, Tomlinson JW. Hormonal Regulation of Lipogenesis. VITAMINS & HORMONES 2013; 91:1-27. [DOI: 10.1016/b978-0-12-407766-9.00001-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Wang X, Huang M, Wang Y. The effect of insulin, TNFα and DHA on the proliferation, differentiation and lipolysis of preadipocytes isolated from large yellow croaker (Pseudosciaena Crocea R.). PLoS One 2012; 7:e48069. [PMID: 23110176 PMCID: PMC3482209 DOI: 10.1371/journal.pone.0048069] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2012] [Accepted: 09/20/2012] [Indexed: 01/19/2023] Open
Abstract
Fish final product can be affected by excessive lipid accumulation. Therefore, it is important to develop strategies to control obesity in cultivated fish to strengthen the sustainability of the aquaculture industry. As in mammals, the development of adiposity in fish depends on hormonal, cytokine and dietary factors. In this study, we investigated the proliferation and differentiation of preadipocytes isolated from the large yellow croaker and examined the effects of critical factors such as insulin, TNFα and DHA on the proliferation, differentiation and lipolysis of adipocytes. Preadipocytes were isolated by collagenase digestion, after which their proliferation was evaluated. The differentiation process was optimized by assaying glycerol-3-phosphate dehydrogenase (GPDH) activity. Oil red O staining and electron microscopy were performed to visualize the accumulated triacylglycerol. Gene transcript levels were measured using SYBR green quantitative real-time PCR. Insulin promoted preadipocytes proliferation, stimulated cell differentiation and decreased lipolysis of mature adipocytes. TNFα and DHA inhibited cell proliferation and differentiation. While TNFα stimulated mature adipocyte lipolysis, DHA showed no lipolytic effect on adipocytes. The expressions of adipose triglyceride lipase (ATGL), fatty acid synthase (FAS), lipoprotein lipase (LPL) and peroxisome proliferator-activated receptor α, γ (PPARα, PPARγ) were quantified during preadipocytes differentiation and adipocytes lipolysis to partly explain the regulation mechanisms. In summary, the results of this study indicated that although preadipocytes proliferation and the differentiation process in large yellow croaker are similar to these processes in mammals, the effects of critical factors such as insulin, TNFα and DHA on fish adipocytes development are not exactly the same. Our findings fill in the gaps in the basic data regarding the effects of critical factors on adiposity development in fish and will facilitate the further study of molecular mechanism by which these factors act in fish and the application of this knowledge to eventually control obesity in cultured species.
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Affiliation(s)
- Xinxia Wang
- Institute of Feed Science, Zhejiang University, Hangzhou, Zhejiang Province, People’s Republic of China
| | - Ming Huang
- Institute of Feed Science, Zhejiang University, Hangzhou, Zhejiang Province, People’s Republic of China
| | - Yizhen Wang
- Institute of Feed Science, Zhejiang University, Hangzhou, Zhejiang Province, People’s Republic of China
- * E-mail:
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Yousefi B, Darabi M, Baradaran B, Shekari Khaniani M, Rahbani M, Darabi M, Fayezi S, Mehdizadeh A, Saliani N, Shaaker M. Inhibition of MEK/ERK1/2 Signaling Affects the Fatty Acid Composition of HepG2 Human Hepatic Cell Line. BIOIMPACTS : BI 2012; 2:145-50. [PMID: 23678452 DOI: 10.5681/bi.2012.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 06/18/2012] [Accepted: 06/19/2012] [Indexed: 01/22/2023]
Abstract
INTRODUCTION The extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase pathway, also known as the MEK/ERK1/2 kinase cascade, has recently been implicated in the regulation of lipid metabolism and fatty liver disease. However, its functional effect on cellular fatty acid composition is unknown. Herein, we examined the effect of a pharmacological inhibitor of MEK, the upstream kinase activator of ERK1/2, on fatty acid composition of hepatocellular carcinoma cell line HepG2. METHODS HepG2 cells cultured in RPMI-1640 were exposed to the commonly used ERK1/2 pathway inhibitor PD98059 and were investigated with respect to fatty acid composition by gas-liquid chromatography. RESULTS Exposure of cells to the ERK1/2 pathway inhibitor induced an increase in monounsaturated fatty acids and the fatty acid desaturation index and a decrease in polyunsaturated fatty acid content. Specifically, we showed a significant increase of oleic acid (18:1n-9; +29%, P=0.003) and arachidonic acid (20:4n-6)/linoleic acid (18:2n-6) ratio (3.5-fold; P<0.001) in HepG2 cells. CONCLUSION Cellular fatty acid composition of HepG2 cells appeared to be differentially regulated by ERK1/2 pathway, thus suggesting related metabolic pathways as potential mediators of the effects of ERK1/2 signaling on hepatic fatty acid composition.
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Affiliation(s)
- Bahman Yousefi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Gnoni GV, Rochira A, Leone A, Damiano F, Marsigliante S, Siculella L. 3,5,3'triiodo-L-thyronine induces SREBP-1 expression by non-genomic actions in human HEP G2 cells. J Cell Physiol 2012; 227:2388-97. [PMID: 21826653 DOI: 10.1002/jcp.22974] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Liver is an important target for thyroid hormone actions. T(3) exerts its effects by two mechanisms: (i) Genomic actions consisting of T(3) link to nuclear receptors that bind responsive elements in the promoter of target genes, (ii) non-genomic actions including integrin αvb3 receptor-mediated MAPK/ERK and PI3K/Akt/mTOR-C1 activation. SREBP-1a, SREBP-1c, and SREBP-2 are transcription factors involved in the regulation of lipogenic genes. We show in Hep G2 cells that T(3) determined a dose- and time-dependent increase in the level of the precursor form of SREBP-1 without affecting SREBP-1 mRNA abundance. T(3) also induced phosphorylation of ERK1/2, Akt and of mTOR-C1 target S6K-P70, and the cytosol-to-membrane translocation of PKC-α. Modulation of SREBP-1 protein level by T(3) was dependent on MAPK/ERK, PI3K/Akt/mTOR-C1 pathway activation since the MEK inhibitor PD98059 or the PI3K inhibitor LY294002 abolished the stimulatory effect of T(3) . Conversely, the effect of T(3) on SREBP-1 level was enhanced by using rapamycin, mTOR-C1 inhibitor. These data suggest a negative control of mTOR-C1 target S6K-P70 on PI3K/Akt pathway. The effect of T(3) on SREBP-1 content increased also by using PKC inhibitors. These inhibitors increased the action of T(3) on Akt phosphorylation suggesting that conventional PKCs may work as negative regulators of the T(3) -dependent SREBP-1 increase. T(3) effects were partially abrogated by tetrac, an inhibitor of the T(3) -αvβ3 receptor interaction and partially evoked by T(3) analog T(3) -agarose. These findings support a model in which T(3) activates intracellular signaling pathways which may be involved in the increment of SREBP-1 level through an IRES-mediated translation mechanism.
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Affiliation(s)
- Gabriele V Gnoni
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Via Prov.le Lecce-Monteroni, Lecce, Italy.
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Polakof S, Médale F, Larroquet L, Vachot C, Corraze G, Panserat S. Regulation of de novo hepatic lipogenesis by insulin infusion in rainbow trout fed a high-carbohydrate diet. J Anim Sci 2011; 89:3079-88. [PMID: 21571891 DOI: 10.2527/jas.2010-3733] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Carbohydrate energy intake in excess of total energy expenditure is converted to fat. In fish, the liver is considered to be the main lipogenic tissue. Its regulation by insulin is not fully understood, and some of the available in vivo findings are contradictory. In this study, bovine insulin was infused for 5 d into rainbow trout fed a high-carbohydrate diet, and variables of de novo hepatic lipogenesis were measured. We found that hepatic lipogenesis in trout is stimulated by insulin, reflected in enhanced mRNA and protein abundance and enzyme activity of ATP-citrate lyase, acetyl-CoA carboxylase, and fatty acid synthase. These results were further supported by parallel changes in enzymes acting as NAD phosphate donors, especially those participating in the pentose phosphate pathway. This is the first time that the main enzymes involved in de novo hepatic lipogenesis have been studied at the molecular, protein, and activity levels in fish. We hypothesize that some of the delayed changes found in the different levels of regulation were probably related to the insulin resistance achieved by the trout liver after 5 d of insulin infusion. We assessed enzyme activity and mRNA abundance of lipid oxidation-related enzymes in the livers of insulin-infused fish in which paradoxically increased β-oxidation potential was found. The insulin-stimulated de novo hepatic lipogenesis in carbohydrate-fed trout reinforces the hypothesis that this pathway may act as an important sink for excess glucose, which could ultimately contribute to improved glucose homeostasis in this carnivorous and glucose-intolerant species when fed high-carbohydrate diets.
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Affiliation(s)
- S Polakof
- INRA, UR1067 Nutrition Metabolism Aquaculture, F-64310 Saint-Pée-sur-Nivelle, France.
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Antidiabetic and antisteatotic effects of the selective fatty acid synthase (FAS) inhibitor platensimycin in mouse models of diabetes. Proc Natl Acad Sci U S A 2011; 108:5378-83. [PMID: 21389266 DOI: 10.1073/pnas.1002588108] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Platensimycin (PTM) is a recently discovered broad-spectrum antibiotic produced by Streptomyces platensis. It acts by selectively inhibiting the elongation-condensing enzyme FabF of the fatty acid biosynthesis pathway in bacteria. We report here that PTM is also a potent and highly selective inhibitor of mammalian fatty acid synthase. In contrast to two agents, C75 and cerulenin, that are widely used as inhibitors of mammalian fatty acid synthase, platensimycin specifically inhibits fatty acid synthesis but not sterol synthesis in rat primary hepatocytes. PTM preferentially concentrates in liver when administered orally to mice and potently inhibits hepatic de novo lipogenesis, reduces fatty acid oxidation, and increases glucose oxidation. Chronic administration of platensimycin led to a net reduction in liver triglyceride levels and improved insulin sensitivity in db/+ mice fed a high-fructose diet. PTM also reduced ambient glucose levels in db/db mice. These results provide pharmacological proof of concept of inhibiting fatty acid synthase for the treatment of diabetes and related metabolic disorders in animal models.
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Mauvoisin D, Mounier C. Hormonal and nutritional regulation of SCD1 gene expression. Biochimie 2011; 93:78-86. [DOI: 10.1016/j.biochi.2010.08.001] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 07/16/2010] [Accepted: 08/03/2010] [Indexed: 01/08/2023]
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Akpa MM, Point F, Sawadogo S, Radenne A, Mounier C. Inhibition of insulin and T3-induced fatty acid synthase by hexanoate. Lipids 2010; 45:997-1009. [PMID: 20811782 DOI: 10.1007/s11745-010-3465-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Accepted: 08/06/2010] [Indexed: 12/30/2022]
Abstract
Fatty acid synthase (FAS) is responsible for the de novo synthesis of palmitate and stearate. This enzyme is activated by insulin and T(3), and inhibited by fatty acids. In this study, we show that insulin and T(3) have an inducing effect on FAS enzymatic activity, which is synergetic when both hormones are present. Octanoate and hexanoate specifically inhibit this hormonal effect. A similar inhibitory effect is observed at the level of protein expression. Transient transfections in HepG2 cells revealed that hexanoate inhibits, at least in part, FAS at a transcriptional level targeting the T(3) response element (TRE) on the FAS promoter. The effect of C6 on FAS expression cannot be attributed to a modification of insulin receptor activation or to a decrease in T(3) entry in the cells. Using bromo-hexanoate, we determined that hexanoate needs to undergo a transformation in order to have an effect. When incubating cells with triglyceride-hexanoate or carnitine-hexanoate, no effect on the enzymatic activity induced by insulin and T(3) is observed. A similar result was obtained when cells were incubated with betulinic acid, an inhibitor of the diacylglycerol acyltransferase. However, the incubation of cells with Triacsin C, a general inhibitor of acyl-CoA synthetases, completely reversed the inhibitory effect of hexanoate. Our results suggest that in hepatic cells, hexanoate needs to be activated into a CoA derivative in order to inhibit the insulin and T(3)-induced FAS expression. This effect is partially transcriptional, targeting the TRE on the FAS promoter.
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Affiliation(s)
- Murielle M Akpa
- Département des Sciences Biologiques, Centre de Recherche BioMed, Université du Québec à Montréal, C.P. 8888, Succursale Centre-ville, Montréal, H3C 3P8, Canada
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Gauthier K, Billon C, Bissler M, Beylot M, Lobaccaro JM, Vanacker JM, Samarut J. Thyroid hormone receptor beta (TRbeta) and liver X receptor (LXR) regulate carbohydrate-response element-binding protein (ChREBP) expression in a tissue-selective manner. J Biol Chem 2010; 285:28156-63. [PMID: 20615868 DOI: 10.1074/jbc.m110.146241] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Thyroid hormone (TR) and liver X (LXR) receptors are transcription factors involved in lipogenesis. Both receptors recognize the same consensus DNA-response element in vitro. It was previously shown that their signaling pathways interact in the control of cholesterol elimination in the liver. In the present study, carbohydrate-response element-binding protein (ChREBP), a major transcription factor controlling the activation of glucose-induced lipogenesis in liver, is characterized as a direct target of thyroid hormones (TH) in liver and white adipose tissue (WAT), the two main lipogenic tissues in mice. Using genetic and molecular approaches, ChREBP is shown to be specifically regulated by TRbeta but not by TRalpha in vivo, even in WAT where both TR isoforms are expressed. However, this isotype specificity is not found in vitro. This TRbeta specific regulation correlates with the loss of TH-induced lipogenesis in TRbeta(-/-) mice. Fasting/refeeding experiments show that TRbeta is not required for the activation of ChREBP expression particularly marked in WAT following refeeding. However, TH can stimulate ChREBP expression in WAT even under fasting conditions, suggesting completely independent pathways. Because ChREBP has been described as an LXR target, the interaction of LXR and TRbeta in ChREBP regulation was assayed both in vitro and in vivo. Each receptor recognizes a different response element on the ChREBP promoter, located only 8 bp apart. There is a cross-talk between LXR and TRbeta signaling on the ChREBP promoter in liver but not in WAT where LXR does not regulate ChREBP expression. The molecular basis for this cross-talk has been determined in in vitro systems.
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Affiliation(s)
- Karine Gauthier
- Institut de Génomique Fonctionnelle de Lyon, Université Lyon 1, CNRS, INRA, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon, France.
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Possible protective role of pregnenolone-16α-carbonitrile in lithocholic acid-induced hepatotoxicity through enhanced hepatic lipogenesis. Eur J Pharmacol 2010; 636:145-54. [DOI: 10.1016/j.ejphar.2010.03.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 02/25/2010] [Accepted: 03/12/2010] [Indexed: 01/04/2023]
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