101
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Haiyan W, Linyi L, Lingling Q, Dongchao W, Yueying J, Xinli W, Tunhai X, Tonghua L. Mixture of five herbal extracts ameliorates pioglitazone-induced aggravation of hepatic steatosis via activating the adiponectin receptor 2/AMP-activated protein kinase signal pathway in diabetic KKAy mice. J TRADIT CHIN MED 2017. [DOI: 10.1016/s0254-6272(17)30311-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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102
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de la Rosa Rodriguez MA, Kersten S. Regulation of lipid droplet-associated proteins by peroxisome proliferator-activated receptors. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:1212-1220. [DOI: 10.1016/j.bbalip.2017.07.007] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 07/13/2017] [Accepted: 07/14/2017] [Indexed: 12/24/2022]
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103
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Gao G, Chen FJ, Zhou L, Su L, Xu D, Xu L, Li P. Control of lipid droplet fusion and growth by CIDE family proteins. Biochim Biophys Acta Mol Cell Biol Lipids 2017. [DOI: 10.1016/j.bbalip.2017.06.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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104
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Armour SM, Remsberg JR, Damle M, Sidoli S, Ho WY, Li Z, Garcia BA, Lazar MA. An HDAC3-PROX1 corepressor module acts on HNF4α to control hepatic triglycerides. Nat Commun 2017; 8:549. [PMID: 28916805 PMCID: PMC5601916 DOI: 10.1038/s41467-017-00772-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 07/26/2017] [Indexed: 01/23/2023] Open
Abstract
The histone deacetylase HDAC3 is a critical mediator of hepatic lipid metabolism, and liver-specific deletion of HDAC3 leads to fatty liver. To elucidate the underlying mechanism, here we report a method of cross-linking followed by mass spectrometry to define a high-confidence HDAC3 interactome in vivo that includes the canonical NCoR-HDAC3 complex as well as Prospero-related homeobox 1 protein (PROX1). HDAC3 and PROX1 co-localize extensively on the mouse liver genome, and are co-recruited by hepatocyte nuclear factor 4α (HNF4α). The HDAC3-PROX1 module controls the expression of a gene program regulating lipid homeostasis, and hepatic-specific ablation of either component increases triglyceride content in liver. These findings underscore the importance of specific combinations of transcription factors and coregulators in the fine tuning of organismal metabolism.HDAC3 is a critical mediator of hepatic lipid metabolism and its loss leads to fatty liver. Here, the authors characterize the liver HDAC3 interactome in vivo, provide evidence that HDAC3 interacts with PROX1, and show that HDAC3 and PROX1 control expression of genes regulating lipid homeostasis.
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Affiliation(s)
- Sean M Armour
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.,Divison of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Jarrett R Remsberg
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.,Divison of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.,Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Manashree Damle
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.,Divison of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Simone Sidoli
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Wesley Y Ho
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.,Divison of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Zhenghui Li
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.,Divison of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Benjamin A Garcia
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA
| | - Mitchell A Lazar
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA. .,Divison of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 3400 Civic Center Boulevard, SCTR 12-102, Philadelphia, PA, 19104, USA.
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105
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Nishimoto Y, Tamori Y. CIDE Family-Mediated Unique Lipid Droplet Morphology in White Adipose Tissue and Brown Adipose Tissue Determines the Adipocyte Energy Metabolism. J Atheroscler Thromb 2017; 24:989-998. [PMID: 28883211 PMCID: PMC5656771 DOI: 10.5551/jat.rv17011] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
White adipose tissue (WAT) stores energy as triacylglycerol in preparation for fasting state. In contrast, brown adipose tissue (BAT) consumes energy and produces heat in a cold environment. One of the major differences between these two adipose tissues is the morphology of the intracellular lipid droplet (LD), which is large and unilocular in WAT and small and multilocular in BAT. Although the fat-specific protein 27 alpha (FSP27α), belonging to the cell death-inducing DNA fragmentation factor A (DFFA)-like effector (Cide) family, was known to be indispensable for large unilocular LD formation in WAT, the mechanism that regulated small multilocular LD formation in BAT remained unknown. We recently uncovered that FSP27β, a novel isoform of FSP27 abundantly expressed in BAT, plays a crucial role in small multilocular LD formation by inhibiting the homodimerization of CideA in BAT. We speculate that unilocular LD formation is ideal for efficient lipid storage in WAT because lipolysis from the LD surface is restricted due to the minimum LD surface area. In addition, hydrolyzed free fatty acid (FFA) and glycerol can efficiently flow out into the circulation from the cell surface. In contrast, small multilocular LD formation is ideal for efficient intracellular lipolysis from the LD surface and the subsequent facilitation of FFA transport to mitochondria that are adjacent to LDs for β-oxidation in BAT. Thus, intracellular LD morphology is closely related to the functions and characteristics of adipose tissues. Given that the browning of adipose tissue leads to enhanced energy expenditure and the prevention of obesity, clarification of the mechanism with respect to intracellular LD formation is very meaningful.
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Affiliation(s)
- Yuki Nishimoto
- Department of Internal Medicine, Division of Diabetes and Endocrinology, Kobe University Graduate School of Medicine
| | - Yoshikazu Tamori
- Department of Internal Medicine, Division of Diabetes and Endocrinology, Kobe University Graduate School of Medicine.,Department of Internal Medicine, Division of Diabetes and Endocrinology, Chibune General Hospital
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106
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Rajamoorthi A, Arias N, Basta J, Lee RG, Baldán Á. Amelioration of diet-induced steatohepatitis in mice following combined therapy with ASO-Fsp27 and fenofibrate. J Lipid Res 2017; 58:2127-2138. [PMID: 28874443 PMCID: PMC5665668 DOI: 10.1194/jlr.m077941] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/18/2017] [Indexed: 12/16/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease. NAFLD progresses from benign steatosis to steatohepatitis (NASH) to cirrhosis and is linked to hepatocellular carcinoma. No targeted treatment is currently approved for NAFLD/NASH. We previously showed that fat-specific protein 27 (FSP27), a lipid droplet-associated protein that controls triglyceride turnover in the hepatocyte, is required for fasting- and diet-induced triglyceride accumulation in the liver. However, silencing Fsp27 with antisense oligonucleotides (ASOs) did not improve hepatosteatosis in genetic nor nutritional mouse models of obesity. Herein, we tested the therapeutic potential of ASO-Fsp27 when used in combination with the PPARα agonist fenofibrate. C57BL/6 mice were fed a high-trans-fat, high-cholesterol, high-fructose diet for eight weeks to establish NASH, then kept on diet for six additional weeks while dosed with ASOs and fenofibrate, alone or in combination. Data show that ASO-Fsp27 and fenofibrate synergize to promote resistance to diet-induced obesity and hypertriglyceridemia and to reverse hepatic steatosis, inflammation, oxidative stress, and fibrosis. This multifactorial improvement of liver disease noted when combining both drugs suggests that a course of treatment that includes both reduced FSP27 activity and activation of PPARα could provide therapeutic benefit to patients with NAFLD/NASH.
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Affiliation(s)
- Ananthi Rajamoorthi
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, Saint Louis, MO
| | - Noemí Arias
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, Saint Louis, MO
| | - Jeannine Basta
- Department of Internal Medicine, Saint Louis University, Saint Louis, MO
| | - Richard G Lee
- Cardiovascular Group, Antisense Drug Discovery, Ionis Pharmaceuticals, Carlsbad, CA
| | - Ángel Baldán
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University, Saint Louis, MO .,Center for Cardiovascular Research, Saint Louis University, Saint Louis, MO.,Liver Center, Saint Louis University, Saint Louis, MO
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107
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Yasumoto J, Kasai H, Yoshimura K, Otoguro T, Watashi K, Wakita T, Yamashita A, Tanaka T, Takeda S, Moriishi K. Hepatitis B virus prevents excessive viral production via reduction of cell death-inducing DFF45-like effectors. J Gen Virol 2017; 98:1762-1773. [PMID: 28745269 DOI: 10.1099/jgv.0.000813] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The relationship between hepatitis B virus (HBV) infection and lipid accumulation remains largely unknown. In this study, we investigated the effect of HBV propagation on lipid droplet growth in HBV-infected cells and HBV-producing cell lines, HepG2.2.15 and HBV-inducible Hep38.7-Tet. The amount of intracellular triglycerides was significantly reduced in HBV-infected and HBV-producing cells compared with HBV-lacking control cells. Electron and immunofluorescent microscopic analyses showed that the average size of a single lipid droplet (LD) was significantly less in the HBV-infected and HBV-producing cells than in the HBV-lacking control cells. Cell death-inducing DFF45-like effectors (CIDEs) B and C (CIDEB and CIDEC), which are involved in LD expansion for the improvement of lipid storage, were expressed at a significantly lower level in HBV-infected or HBV-producing cells than in HBV-lacking control cells, while CIDEA was not detected in those cells regardless of HBV production. The activity of the CIDEB and CIDEC gene promoters was impaired in HBV-infected or HBV-producing cells compared to HBV-lacking control cells, while CIDEs potentiated HBV core promoter activity. The amount of HNF4α, that can promote the transcription of CIDEB was significantly lower in HBV-producing cells than in HBV-lacking control cells. Knockout of CIDEB or CIDEC significantly reduced the amount of supernatant HBV DNA, intracellular viral RNA and nucleocapsid-associated viral DNA, while the expression of CIDEB or CIDEC recovered HBV production in CIDEB- or CIDEC-knockout cells. These results suggest that HBV regulates its own viral replication via CIDEB and CIDEC.
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Affiliation(s)
- Jun Yasumoto
- Department of Microbiology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Hirotake Kasai
- Department of Microbiology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Kentaro Yoshimura
- Department of Anatomy and Cell Biology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Teruhime Otoguro
- Department of Microbiology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Atsuya Yamashita
- Department of Microbiology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Tomohisa Tanaka
- Department of Microbiology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Sen Takeda
- Department of Anatomy and Cell Biology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Kohji Moriishi
- Department of Microbiology, Faculty of Medicine, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Chuo-shi, Yamanashi, Japan
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108
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Gao B, Xu MJ, Bertola A, Wang H, Zhou Z, Liangpunsakul S. Animal Models of Alcoholic Liver Disease: Pathogenesis and Clinical Relevance. Gene Expr 2017; 17:173-186. [PMID: 28411363 PMCID: PMC5500917 DOI: 10.3727/105221617x695519] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Alcoholic liver disease (ALD), a leading cause of chronic liver injury worldwide, comprises a range of disorders including simple steatosis, steatohepatitis, cirrhosis, and hepatocellular carcinoma. Over the last five decades, many animal models for the study of ALD pathogenesis have been developed. Recently, a chronic-plus-binge ethanol feeding model was reported. This model induces significant steatosis, hepatic neutrophil infiltration, and liver injury. A clinically relevant model of high-fat diet feeding plus binge ethanol was also developed, which highlights the risk of excessive binge drinking in obese/overweight individuals. All of these models recapitulate some features of the different stages of ALD and have been widely used by many investigators to study the pathogenesis of ALD and to test for therapeutic drugs/components. However, these models are somewhat variable, depending on mouse genetic background, ethanol dose, and animal facility environment. This review focuses on these models and discusses these variations and some methods to improve the feeding protocol. The pathogenesis, clinical relevance, and translational studies of these models are also discussed.
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Affiliation(s)
- Bin Gao
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Ming-Jiang Xu
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Adeline Bertola
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
- †Université Côte d’Azur, INSERM, Centre Méditerranéen de Médecine Moléculaire, Nice, France
| | - Hua Wang
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
- ‡Department of Oncology, The First Affiliated Hospital, Institute for Liver Diseases of Anhui Medical University, Hefei, P.R. China
| | - Zhou Zhou
- *Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Suthat Liangpunsakul
- §Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
- ¶Roudebush Veterans Administration Medical Center, Indianapolis, IN, USA
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109
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Wang W, Xu MJ, Cai Y, Zhou Z, Cao H, Mukhopadhyay P, Pacher P, Zheng S, Gonzalez FJ, Gao B. Inflammation is independent of steatosis in a murine model of steatohepatitis. Hepatology 2017; 66:108-123. [PMID: 28220523 PMCID: PMC5481491 DOI: 10.1002/hep.29129] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/30/2017] [Accepted: 02/17/2017] [Indexed: 12/17/2022]
Abstract
UNLABELLED Obesity and alcohol consumption synergistically promote steatohepatitis, and neutrophil infiltration is believed to be associated with steatosis. However, the underlying mechanisms remain obscure. Peroxisome proliferator-activated receptor gamma (PPARγ) plays a complex role in lipid metabolism and inflammation; therefore, the purpose of this study was to dissect its role in regulating steatosis and neutrophil infiltration in a clinically relevant mouse steatohepatitis model of 3-month high-fat diet (HFD) feeding plus a binge of ethanol (HFD-plus-binge ethanol). Hepatocyte-specific Pparg disruption reduced liver steatosis but surprisingly increased hepatic neutrophil infiltration after HFD-plus-binge ethanol. Knockout or knockdown of the PPARγ target gene, fat-specific protein 27, reduced steatosis without affecting neutrophil infiltration in this model. Moreover, hepatocyte-specific deletion of the Pparg gene, but not the fat-specific protein 27 gene, markedly up-regulated hepatic levels of the gene for chemokine (C-X-C motif) ligand 1 (Cxcl1, a chemokine for neutrophil infiltration) in HFD-plus-binge ethanol-fed mice. In vitro, deletion of the Pparg gene also highly augmented palmitic acid or tumor necrosis factor alpha induction of Cxcl1 in mouse hepatocytes. In contrast, activation of PPARγ with a PPARγ agonist attenuated Cxcl1 expression in hepatocytes. Palmitic acid also up-regulated interleukin-8 (a key chemokine for human neutrophil recruitment) expression in human hepatocytes, which was attenuated and enhanced by cotreatment with a PPARγ agonist and antagonist, respectively. Finally, acute ethanol binge markedly attenuated HFD-induced hepatic PPARγ activation, which contributed to the up-regulation of hepatic Cxcl1 expression post-HFD-plus-binge ethanol. CONCLUSION Hepatic PPARγ plays an opposing role in controlling steatosis and neutrophil infiltration, leading to dissociation between steatosis and inflammation; acute ethanol gavage attenuates hepatic PPARγ activation and subsequently up-regulates hepatic CXCL1/interleukin-8 expression, thereby exacerbating hepatic neutrophil infiltration. (Hepatology 2017;66:108-123).
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Affiliation(s)
- Wei Wang
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA,Department of Surgery, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Ming-Jiang Xu
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yan Cai
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Zhou Zhou
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Haixia Cao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Partha Mukhopadhyay
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Pal Pacher
- Laboratory of Cardiovascular Physiology and Tissue Injury, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Shusen Zheng
- Department of Surgery, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Frank J Gonzalez
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
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110
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Li J, Liu G, Zhang F, Zhang Z, Xu Y, Li Q. Role of glycoprotein 78 and cidec in hepatic steatosis. Mol Med Rep 2017; 16:1871-1877. [PMID: 28656280 PMCID: PMC5561988 DOI: 10.3892/mmr.2017.6834] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 03/20/2017] [Indexed: 12/15/2022] Open
Abstract
Hepatic glycoprotein (gp78), a membrane-anchored E3 ubiquitin ligase, has been reported to be involved in regulating lipid and energy metabolism in animals, and cell death-inducing DFFA-like effector c (cidec) has emerged as an important regulator of metabolism, which has been implicated in the process of fat differentiation. Nonalcoholic fatty liver disease is a metabolic disorder associated with hepatic steatosis. In the present study, to investigate the role of gp78 and cidec in hepatic steatosis, an in vitro cell culture model of hepatic steatosis was established, using the AML12 mouse hepatocyte cell line to assess the protein expression of gp78. The results of Oil Red O staining, phase contrast microscopy and triglyceride content detection experiments indicated that the overexpression of gp78 induced lipid accumulation, whereas gp78-knockdown led to a reduction in lipid accumulation in the AML12 cells. The increased expression of gp78 was associated with steatosis. The expression of cidec was consistent with gp78, and the colocalization of gp78 and cidec was observed on the surface of lipid droplets using immunofluorescence analysis. Furthermore, an interaction between gp78 and cidec was detected using coimmunoprecipitation analysis, and this interaction promoted lipid accumulation. Based on these data, it was hypothesized that gp78 is a regulator of hepatic steatosis, and that it may be a putative molecular mediator in metabolic diseases.
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Affiliation(s)
- Jie Li
- State Key Laboratory of Cancer Biology, Department of Pathology, Xijing Hospital, Basic Medical College, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Guocai Liu
- The Third Department of Internal Medicine, The 273 Hospital of Chinese PLA, Korla, Xinjiang 84100, P.R. China
| | - Feng Zhang
- State Key Laboratory of Cancer Biology, Department of Pathology, Xijing Hospital, Basic Medical College, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Zhiwen Zhang
- State Key Laboratory of Cancer Biology, Department of Pathology, Xijing Hospital, Basic Medical College, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Yuqiao Xu
- State Key Laboratory of Cancer Biology, Department of Pathology, Xijing Hospital, Basic Medical College, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
| | - Qing Li
- State Key Laboratory of Cancer Biology, Department of Pathology, Xijing Hospital, Basic Medical College, Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China
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111
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Matsuo K, Matsusue K, Aibara D, Takiguchi S, Gonzalez FJ, Yamano S. Insulin Represses Fasting-Induced Expression of Hepatic Fat-Specific Protein 27. Biol Pharm Bull 2017; 40:888-893. [PMID: 28566630 DOI: 10.1248/bpb.b17-00105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The fat-specific protein 27 (Fsp27) gene belongs to the cell death-inducing DNA fragmentation factor 45-like effector family. Fsp27 is highly expressed in adipose tissue as well as the fatty liver of ob/ob mice. Fsp27 is directly regulated by the peroxisome proliferator-activated receptor γ (PPARγ) in livers of genetically obese leptin deficient ob/ob mice. In the present study, Fsp27 was markedly induced by 24 h fasting in genetically normal mouse livers and repressed by refeeding a high sucrose diet. In contrast with the liver, Fsp27 expression was decreased in adipose tissue by fasting and increased by refeeding. Interestingly, fasting-induced Fsp27 liver expression was independent of PPARγ. Moreover, Fsp27 expression was induced in the insulin-depleted livers of streptozotocin-treated mice. Finally, Fsp27 expression was repressed by direct injection of glucose or insulin in fasting mice. These results suggest that insulin represses Fsp27 expression in the fasting liver.
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Affiliation(s)
- Kohei Matsuo
- Faculty of Pharmaceutical Science, Fukuoka University
| | | | | | | | - Frank J Gonzalez
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health
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112
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Gluchowski NL, Becuwe M, Walther TC, Farese RV. Lipid droplets and liver disease: from basic biology to clinical implications. Nat Rev Gastroenterol Hepatol 2017; 14:343-355. [PMID: 28428634 PMCID: PMC6319657 DOI: 10.1038/nrgastro.2017.32] [Citation(s) in RCA: 389] [Impact Index Per Article: 55.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lipid droplets are dynamic organelles that store neutral lipids during times of energy excess and serve as an energy reservoir during deprivation. Many prevalent metabolic diseases, such as the metabolic syndrome or obesity, often result in abnormal lipid accumulation in lipid droplets in the liver, also called hepatic steatosis. Obesity-related steatosis, or NAFLD in particular, is a major public health concern worldwide and is frequently associated with insulin resistance and type 2 diabetes mellitus. Here, we review the latest insights into the biology of lipid droplets and their role in maintaining lipid homeostasis in the liver. We also offer a perspective of liver diseases that feature lipid accumulation in these lipid storage organelles, which include NAFLD and viral hepatitis. Although clinical applications of this knowledge are just beginning, we highlight new opportunities for identifying molecular targets for treating hepatic steatosis and steatohepatitis.
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Affiliation(s)
- Nina L. Gluchowski
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA.,Boston Children’s Hospital Department of Gastroenterology, Hepatology and Nutrition, 300 Longwood Avenue Boston, Massachusetts 02115, USA
| | - Michel Becuwe
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA
| | - Tobias C. Walther
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA.,Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue Boston, Massachusetts 02115, USA.,Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur Boston, Massachusetts 02115, USA.,Howard Hughes Medical Institute, Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA
| | - Robert V. Farese
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA.,Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue Boston, Massachusetts 02115, USA.,Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur Boston, Massachusetts 02115, USA
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113
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Tanaka N, Aoyama T, Kimura S, Gonzalez FJ. Targeting nuclear receptors for the treatment of fatty liver disease. Pharmacol Ther 2017; 179:142-157. [PMID: 28546081 DOI: 10.1016/j.pharmthera.2017.05.011] [Citation(s) in RCA: 149] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ligand-activated nuclear receptors, including peroxisome proliferator-activated receptor alpha (PPARα), pregnane X receptor, and constitutive androstane receptor, were first identified as key regulators of the responses against chemical toxicants. However, numerous studies using mouse disease models and human samples have revealed critical roles for these receptors and others, such as PPARβ/δ, PPARγ, farnesoid X receptor (FXR), and liver X receptor (LXR), in maintaining nutrient/energy homeostasis in part through modulation of the gut-liver-adipose axis. Recently, disorders associated with disrupted nutrient/energy homeostasis, e.g., obesity, metabolic syndrome, and non-alcoholic fatty liver disease (NAFLD), are increasing worldwide. Notably, in NAFLD, a progressive subtype exists, designated as non-alcoholic steatohepatitis (NASH) that is characterized by typical histological features resembling alcoholic steatohepatitis (ASH), and NASH/ASH are recognized as major causes of hepatitis virus-unrelated liver cirrhosis and hepatocellular carcinoma. Since hepatic steatosis is basically caused by an imbalance between fat/energy influx and utilization, abnormal signaling of these nuclear receptors contribute to the pathogenesis of fatty liver disease. Standard therapeutic interventions have not been fully established for fatty liver disease, but some new agents that activate or inhibit nuclear receptor signaling have shown promise as possible therapeutic targets. In this review, we summarize recent findings on the roles of nuclear receptors in fatty liver disease and discuss future perspectives to develop promising pharmacological strategies targeting nuclear receptors for NAFLD/NASH.
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Affiliation(s)
- Naoki Tanaka
- Department of Metabolic Regulation, Shinshu University Graduate School of Medicine, Matsumoto, Nagano, Japan.
| | - Toshifumi Aoyama
- Department of Metabolic Regulation, Shinshu University Graduate School of Medicine, Matsumoto, Nagano, Japan
| | - Shioko Kimura
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Frank J Gonzalez
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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Yang Y, Lin Y, Duan X, Lv H, Xing W, Li Q, Gao X, Hou X. The effects of cell death-inducing DNA fragmentation factor-α-like effector C (CIDEC) on milk lipid synthesis in mammary glands of dairy cows. J Dairy Sci 2017; 100:4014-4024. [DOI: 10.3168/jds.2016-11549] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 12/19/2016] [Indexed: 01/14/2023]
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115
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Heit C, Marshall S, Singh S, Yu X, Charkoftaki G, Zhao H, Orlicky DJ, Fritz KS, Thompson DC, Vasiliou V. Catalase deletion promotes prediabetic phenotype in mice. Free Radic Biol Med 2017; 103:48-56. [PMID: 27939935 PMCID: PMC5513671 DOI: 10.1016/j.freeradbiomed.2016.12.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 11/02/2016] [Accepted: 12/07/2016] [Indexed: 01/22/2023]
Abstract
Hydrogen peroxide is produced endogenously and can be toxic to living organisms by inducing oxidative stress and cell damage. However, it has also been identified as a signal transduction molecule. By metabolizing hydrogen peroxide, catalase protects cells and tissues against oxidative damage and may also influence signal transduction mechanisms. Studies suggest that acatalasemic individuals (i.e., those with very low catalase activity) have a higher risk for the development of diabetes. We now report catalase knockout (Cat-/-) mice, when fed a normal (6.5% lipid) chow, exhibit an obese phenotype that manifests as an increase in body weight that becomes more pronounced with age. The mice demonstrate altered hepatic and muscle lipid deposition, as well as increases in serum and hepatic triglycerides (TGs), and increased hepatic transcription and protein expression of PPARγ. Liver morphology revealed steatosis with inflammation. Cat-/- mice also exhibited pancreatic morphological changes that correlated with impaired glucose tolerance and increased fasting serum insulin levels, conditions consistent with pre-diabetic status. RNA-seq analyses revealed a differential expression of pathways and genes in Cat-/- mice, many of which are related to metabolic syndrome, diabetes, and obesity, such as Pparg and Cidec. In conclusion, the results of the present study show mice devoid of catalase develop an obese, pre-diabetic phenotype and provide compelling evidence for catalase (or its products) being integral in metabolic regulation.
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Affiliation(s)
- Claire Heit
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver Anschutz Medical Campus, 12850 East Montview Boulevard, Aurora, CO 80045, USA
| | - Stephanie Marshall
- Department of Environmental Health Services, Yale School of Public Health, Yale University, 60 College St, New Haven CT 06520-8034, USA
| | - Surrendra Singh
- Department of Environmental Health Services, Yale School of Public Health, Yale University, 60 College St, New Haven CT 06520-8034, USA
| | - Xiaoqing Yu
- Department of Biostatistics, Yale School of Public Health, Yale University, New Haven CT 06520, USA
| | - Georgia Charkoftaki
- Department of Environmental Health Services, Yale School of Public Health, Yale University, 60 College St, New Haven CT 06520-8034, USA
| | - Hongyu Zhao
- Department of Biostatistics, Yale School of Public Health, Yale University, New Haven CT 06520, USA
| | - David J Orlicky
- Department of Pathology, School of Medicine University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Kristofer S Fritz
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver Anschutz Medical Campus, 12850 East Montview Boulevard, Aurora, CO 80045, USA
| | - David C Thompson
- Department of Clinical Pharmacy, School of Pharmacy, University of Colorado Anschutz Medical Campus, 12850 East Montview Boulevard, Aurora, CO 80045, USA
| | - Vasilis Vasiliou
- Department of Environmental Health Services, Yale School of Public Health, Yale University, 60 College St, New Haven CT 06520-8034, USA.
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Abstract
Obesity is a worldwide epidemic that predisposes individuals to cardiometabolic complications, such as type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD), which are all related to inappropriate ectopic lipid deposition. Identification of the pathogenic molecular mechanisms and effective therapeutic approaches are highly needed. The peroxisome proliferator-activated receptors (PPARs) modulate several biological processes that are perturbed in obesity, including inflammation, lipid and glucose metabolism and overall energy homeostasis. Here, we review how PPARs regulate the functions of adipose tissues, such as adipogenesis, lipid storage and adaptive thermogenesis, under healthy and pathological conditions. We also discuss the clinical use and mechanism of PPAR agonists in the treatment of obesity comorbidities such as dyslipidaemia, T2DM and NAFLD. First generation PPAR agonists, primarily those acting on PPARγ, are associated with adverse effects that outweigh their clinical benefits, which led to the discontinuation of their development. An improved understanding of the physiological roles of PPARs might, therefore, enable the development of safe, new PPAR agonists with improved therapeutic potential.
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Affiliation(s)
- Barbara Gross
- Université de Lille, INSERM, CHU Lille, Institut Pasteur de Lille, U1011-EGID, F-59000 Lille, France
| | - Michal Pawlak
- International Institute of Molecular and Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland
| | - Philippe Lefebvre
- Université de Lille, INSERM, CHU Lille, Institut Pasteur de Lille, U1011-EGID, F-59000 Lille, France
| | - Bart Staels
- Université de Lille, INSERM, CHU Lille, Institut Pasteur de Lille, U1011-EGID, F-59000 Lille, France
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PPARs and Mitochondrial Metabolism: From NAFLD to HCC. PPAR Res 2016; 2016:7403230. [PMID: 28115925 PMCID: PMC5223052 DOI: 10.1155/2016/7403230] [Citation(s) in RCA: 297] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 11/08/2016] [Accepted: 11/10/2016] [Indexed: 11/17/2022] Open
Abstract
Metabolic related diseases, such as type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease (NAFLD), are widespread threats which bring about a significant burden of deaths worldwide, mainly due to cardiovascular events and cancer. The pathogenesis of these diseases is extremely complex, multifactorial, and only partially understood. As the main metabolic organ, the liver is central to maintain whole body energetic homeostasis. At the cellular level, mitochondria are the metabolic hub connecting and integrating all the main biochemical, hormonal, and inflammatory signaling pathways to fulfill the energetic and biosynthetic demand of the cell. In the liver, mitochondria metabolism needs to cope with the energetic regulation of the whole body. The nuclear receptors PPARs orchestrate lipid and glucose metabolism and are involved in a variety of diseases, from metabolic disorders to cancer. In this review, focus is placed on the roles of PPARs in the regulation of liver mitochondrial metabolism in physiology and pathology, from NAFLD to HCC.
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The size matters: regulation of lipid storage by lipid droplet dynamics. SCIENCE CHINA-LIFE SCIENCES 2016; 60:46-56. [PMID: 27981432 DOI: 10.1007/s11427-016-0322-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 10/28/2016] [Indexed: 12/14/2022]
Abstract
Adequate energy storage is essential for sustaining healthy life. Lipid droplet (LD) is the subcellular organelle that stores energy in the form of neutral lipids and releases fatty acids under energy deficient conditions. Energy storage capacity of LDs is primarily dependent on the sizes of LDs. Enlargement and growth of LDs is controlled by two molecular pathways: neutral lipid synthesis and atypical LD fusion. Shrinkage of LDs is mediated by the degradation of neutral lipids under energy demanding conditions and is controlled by neutral cytosolic lipases and lysosomal acidic lipases. In this review, we summarize recent progress regarding the regulatory pathways and molecular mechanisms that control the sizes and the energy storage capacity of LDs.
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119
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Loke SY, Wong PTH, Ong WY. Global gene expression changes in the prefrontal cortex of rabbits with hypercholesterolemia and/or hypertension. Neurochem Int 2016; 102:33-56. [PMID: 27890723 DOI: 10.1016/j.neuint.2016.11.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 11/14/2016] [Accepted: 11/23/2016] [Indexed: 02/01/2023]
Abstract
Although many studies have identified a link between hypercholesterolemia or hypertension and cognitive deficits, till date, comprehensive gene expression analyses of the brain under these conditions is still lacking. The present study was carried out to elucidate differential gene expression changes in the prefrontal cortex (PFC) of New Zealand white rabbits exposed to hypercholesterolemia and/or hypertension with a view of identifying gene networks at risk. Microarray analyses of the PFC of hypercholesterolemic rabbits showed 850 differentially expressed genes (DEGs) in the cortex of hypercholesterolemic rabbits compared to controls, but only 5 DEGs in hypertensive rabbits compared to controls. Up-regulated genes in the PFC of hypercholesterolemic rabbits included CIDEC, ODF2, RNASEL, FSHR, CES3 and MAB21L3, and down-regulated genes included FAM184B, CUL3, LOC100351029, TMEM109, LOC100357097 and PFDN5. Comparison with our previous study on the middle cerebral artery (MCA) of the same rabbits showed many differentially expressed genes in common between the PFC and MCA, during hypercholesterolemia. Moreover, these genes tended to fall into the same functional networks, as revealed by IPA analyses, with many identical node molecules. These include: proteasome, insulin, Akt, ERK1/2, histone, IL12, interferon alpha and NFκB. Of these, PSMB4, PSMD4, PSMG1 were chosen as representatives of genes related to the proteasome for verification by quantitative RT-PCR. Results indicate significant downregulation of all three proteasome associated genes in the PFC. Immunostaining showed significantly increased number of Aβ labelled cells in layers III and V of the cortex after hypercholesterolemia and hypertension, which may be due to decreased proteasome activity and/or increased β- or γ-secretase activity. Knowledge of altered gene networks during hypercholesterolemia and/or hypertension could inform our understanding of the link between these conditions and cognitive deficits in vascular dementia or Alzheimer's disease.
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Affiliation(s)
- Sau-Yeen Loke
- Department of Anatomy, National University of Singapore, 119260, Singapore
| | - Peter Tsun-Hon Wong
- Department of Pharmacology, National University of Singapore, 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, 119260, Singapore; Neurobiology and Ageing Research Program, Life Sciences Institute, National University of Singapore, 119260, Singapore.
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Langhi C, Arias N, Rajamoorthi A, Basta J, Lee RG, Baldán Á. Therapeutic silencing of fat-specific protein 27 improves glycemic control in mouse models of obesity and insulin resistance. J Lipid Res 2016; 58:81-91. [PMID: 27884961 PMCID: PMC5234712 DOI: 10.1194/jlr.m069799] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 11/16/2016] [Indexed: 12/21/2022] Open
Abstract
Obesity is a component of the metabolic syndrome, mechanistically linked to diabetes, fatty liver disease, and cardiovascular disease. Proteins that regulate the metabolic fate of intracellular lipid droplets are potential therapeutic candidates to treat obesity and its related consequences. CIDEC (cell death-inducing DFFA-like effector C), also known in mice as Fsp27 (fat-specific protein 27), is a lipid droplet-associated protein that prevents lipid mobilization and promotes intracellular lipid storage. The consequences of complete loss of FSP27 on hepatic metabolism and on insulin resistance are controversial, as both healthy and deleterious lipodystrophic phenotypes have been reported in Fsp27−/− mice. To test whether therapeutic silencing of Fsp27 might be useful to improve obesity, fatty liver, and glycemic control, we used antisense oligonucleotides (ASOs) in both nutritional (high-fat diet) and genetic (leptin-deficient ob/ob) mouse models of obesity, hyperglycemia, and hepatosteatosis. We show that partial silencing Fsp27 in either model results in the robust decrease in visceral fat, improved insulin sensitivity and whole-body glycemic control, and tissue-specific changes in transcripts controlling lipid oxidation and synthesis. These data suggest that partial reduction of FSP27 activity (e.g., using ASOs) might be exploited therapeutically in insulin-resistant obese or overweight patients.
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Affiliation(s)
- Cédric Langhi
- Edward A. Doisy Department of Biochemistry & Molecular Biology Saint Louis University, Saint Louis, MO 63104
| | - Noemí Arias
- Edward A. Doisy Department of Biochemistry & Molecular Biology Saint Louis University, Saint Louis, MO 63104
| | - Ananthi Rajamoorthi
- Edward A. Doisy Department of Biochemistry & Molecular Biology Saint Louis University, Saint Louis, MO 63104
| | - Jeannine Basta
- Department of Internal Medicine, Saint Louis University, Saint Louis, MO 63104
| | - Richard G Lee
- Cardiovascular Group, Antisense Drug Discovery, Ionis Pharmaceuticals, Carlsbad, CA 92010
| | - Ángel Baldán
- Edward A. Doisy Department of Biochemistry & Molecular Biology Saint Louis University, Saint Louis, MO 63104 .,Center for Cardiovascular Research Saint Louis University, Saint Louis, MO 63104.,Liver Center, Saint Louis University, Saint Louis, MO 63104
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121
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Wang SX, Wei JG, Chen LL, Hu X, Kong W. The role of expression imbalance between adipose synthesis and storage mediated by PPAR-γ/FSP27 in the formation of insulin resistance in catch up growth. Lipids Health Dis 2016; 15:173. [PMID: 27716232 PMCID: PMC5050960 DOI: 10.1186/s12944-016-0319-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 08/30/2016] [Indexed: 01/08/2023] Open
Abstract
Background Catch up growth (CUG) motivated by under-nutrition can lead to insulin resistance (IR) and visceral fat over-accumulation. However, the precise mechanisms on IR induced by adipose tissue changes during CUG remain unresolved. Methods Experimental rats were divided into three groups: normal chow group, catch up growth group and resveratrol administrated group. The whole experiment was carried out in four stages: 4, 6, 8 and 12 weeks. Peroxisome-proliferator activated receptor gamma (PPAR-γ) and fat-specific protein 27 (FSP27) expression level in epididymal adipose tissues (EAT) and subcutaneous adipose tissues (SAT) were detected along with other IR indicators. Results Calorie restriction (CR) significantly increased PPAR-γ expression in EAT while decreased FSP27 expression. During re-feeding, both of the expression of PPAR-γ and FSP27 increased, even FSP27 returned to normal level when CUG for 4 weeks. Although PPAR-γ expression declined slightly at 8 weeks, it was still much stronger than normal chow groups. However, no changes were seen in SAT. Relative insufficiency of FSP27 expression in EAT results in a decrease in lipid storage capacity, causing a series of path physiological changes that led to the formation of IR. Resveratrol inhibited the expression of PPAR-γ and promoted FSP27 expression, thus fundamentally improving IR. Conclusions The imbalance between adipose synthesis and storage mediated by PPAR-γ / FSP27 in the EAT plays a pivotal role in the formation of IR during CUG. Resveratrol can correct fat formation and storage imbalance status by up-regulating FSP27 and down-regulating PPAR-γ expression level, ameliorating insulin sensitivity.
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Affiliation(s)
- Su-Xing Wang
- The Second Department of Geriatrics, Hebei General Hospital, Shijiazhuang, 050051, China
| | - Jin-Gang Wei
- Department of general surgery, The fifth hospital of Shijiazhuang City, Shijiazhuang, 050024, China
| | - Lu-Lu Chen
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
| | - Xiang Hu
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Wen Kong
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
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Li Z, Xiong C, Mo S, Tian H, Yu M, Mao T, Chen Q, Luo H, Li Q, Lu J, Zhao Y, Li W. Comprehensive Transcriptome Analyses of the Fructose-Fed Syrian Golden Hamster Liver Provides Novel Insights into Lipid Metabolism. PLoS One 2016; 11:e0162402. [PMID: 27589064 PMCID: PMC5010245 DOI: 10.1371/journal.pone.0162402] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 07/21/2016] [Indexed: 01/08/2023] Open
Abstract
Dyslipidemia has been widely proven to contribute to cardiovascular diseases and other metabolic disorders, especially in insulin resistance and type 2 diabetes. The overproduction of VLDL is a significant characteristic of dyslipidemia, indicating the dysfunction of hepatic lipid metabolism, from triglyceride synthesis to transport. The fructose-fed Syrian golden hamster is an established animal model for the study of VLDL assembly with insulin resistance, however, it remains unknown how VLDL production is regulated at the transcriptional level due to the absence of a complete hamster genome. Here, we performed deep sequencing and constructed an mRNA-miRNA-lncRNA interaction network of Syrian golden hamster liver in order to reveal the global transcription profile and find potential RNA molecular regulation of VLDL production. We identified 4,450 novel multi-exon hamster lncRNAs and 755 miRNAs expressed in liver. Additionally, 146 differentially expressed coding genes, 27 differentially expressed lncRNA genes, as well as 16 differentially expressed miRNAs were identified. We then constructed an mRNA-miRNA-lncRNA interaction network that may potentially regulate VLDL production, and interestingly found several microRNA-centered regulatory networks. In order to verify our interpretation, miR-486 was selected for further experiments. Overexpression or down-regulation of miR-486 in fructose-fed hamsters resulted in altered hepatic expression of proteins involved in VLDL production, and in modulated levels of circulating VLDL. Our findings implicated that miR-486 is a potential regulator of circulating VLDL levels. These results provide new insights and a valuable resource for further study of the molecular mechanisms of VLDL secretion.
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Affiliation(s)
- Ziyang Li
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Chaoliang Xiong
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Suo Mo
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Haiying Tian
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Mengqian Yu
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Tingting Mao
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Qian Chen
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Haitao Luo
- Key Laboratory of Intelligent Information Processing, Advanced Computer Research Center, State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Quanzhen Li
- Department of Immunology & Microarray Core Facility, The University of Texas Southwestern Medical Center at Dallas, Dallas, TX, 75390, United States of America
| | - Jianxin Lu
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
- Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical University, Wenzhou, 325035, PR China
| | - Yi Zhao
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
- Key Laboratory of Intelligent Information Processing, Advanced Computer Research Center, State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Wei Li
- Key Laboratory of Laboratory Medicine, Ministry of Education of China, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, 325035, PR China
- Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical University, Wenzhou, 325035, PR China
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Ham JR, Lee HI, Choi RY, Sim MO, Choi MS, Kwon EY, Yun KW, Kim MJ, Lee MK. Anti-obesity and anti-hepatosteatosis effects of dietary scopoletin in high-fat diet fed mice. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.06.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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Murakami M, Tognini P, Liu Y, Eckel-Mahan KL, Baldi P, Sassone-Corsi P. Gut microbiota directs PPARγ-driven reprogramming of the liver circadian clock by nutritional challenge. EMBO Rep 2016; 17:1292-303. [PMID: 27418314 DOI: 10.15252/embr.201642463] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/22/2016] [Indexed: 12/20/2022] Open
Abstract
The liver circadian clock is reprogrammed by nutritional challenge through the rewiring of specific transcriptional pathways. As the gut microbiota is tightly connected to host metabolism, whose coordination is governed by the circadian clock, we explored whether gut microbes influence circadian homeostasis and how they distally control the peripheral clock in the liver. Using fecal transplant procedures we reveal that, in response to high-fat diet, the gut microbiota drives PPARγ-mediated activation of newly oscillatory transcriptional programs in the liver. Moreover, antibiotics treatment prevents PPARγ-driven transcription in the liver, underscoring the essential role of gut microbes in clock reprogramming and hepatic circadian homeostasis. Thus, a specific molecular signature characterizes the influence of the gut microbiome in the liver, leading to the transcriptional rewiring of hepatic metabolism.
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Affiliation(s)
- Mari Murakami
- Center for Epigenetics and Metabolism, Department of Biological Chemistry, U904 INSERM, University of California Irvine, Irvine, CA, USA
| | - Paola Tognini
- Center for Epigenetics and Metabolism, Department of Biological Chemistry, U904 INSERM, University of California Irvine, Irvine, CA, USA
| | - Yu Liu
- Institute for Genomics and Bioinformatics, School of Information and Computer Sciences, University of California Irvine, Irvine, CA, USA
| | - Kristin L Eckel-Mahan
- Center for Epigenetics and Metabolism, Department of Biological Chemistry, U904 INSERM, University of California Irvine, Irvine, CA, USA Center for Metabolic and Degenerative Diseases, Institute of Molecular Medicine, University of Texas Health Sciences Center, Houston, TX, USA
| | - Pierre Baldi
- Institute for Genomics and Bioinformatics, School of Information and Computer Sciences, University of California Irvine, Irvine, CA, USA
| | - Paolo Sassone-Corsi
- Center for Epigenetics and Metabolism, Department of Biological Chemistry, U904 INSERM, University of California Irvine, Irvine, CA, USA
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Tsujimoto S, Kishina M, Koda M, Yamamoto Y, Tanaka K, Harada Y, Yoshida A, Hisatome I. Nimesulide, a cyclooxygenase-2 selective inhibitor, suppresses obesity-related non-alcoholic fatty liver disease and hepatic insulin resistance through the regulation of peroxisome proliferator-activated receptor γ. Int J Mol Med 2016; 38:721-8. [PMID: 27431935 PMCID: PMC4990319 DOI: 10.3892/ijmm.2016.2674] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/30/2016] [Indexed: 12/25/2022] Open
Abstract
Cyclooxygenase (COX)-2 selective inhibitors suppress non-alcoholic fatty liver disease (NAFLD); however, the precise mechanism of action remains unknown. The aim of this study was to examine how the COX-2 selective inhibitor nimesulide suppresses NAFLD in a murine model of high-fat diet (HFD)‑induced obesity. Mice were fed either a normal chow diet (NC), an HFD, or HFD plus nimesulide (HFD-nime) for 12 weeks. Body weight, hepatic COX-2 mRNA expression and triglyceride accumulation were significantly increased in the HFD group. Triglyceride accumulation was suppressed in the HFD-nime group. The mRNA expression of hepatic peroxisome proliferator-activated receptor γ (PPARγ) and the natural PPARγ agonist 15-deoxy-Δ12,14-prostaglandin J2 (15d‑PGJ2) were significantly increased in the HFD group and significantly suppressed in the HFD-nime group. Glucose metabolism was impaired in the HFD group compared with the NC group, and it was significantly improved in the HFD-nime group. In addition, the plasma insulin levels in the HFD group were increased compared with those in the NC group, and were decreased in the HFD-nime group. These results indicate that HFD-induced NAFLD is mediated by the increased hepatic expression of COX-2. We suggest that the production of 15d-PGJ2, which is mediated by COX-2, induces NAFLD and hepatic insulin resistance by activating PPARγ. Furthermore, the mRNA expression of tissue inhibitor of metalloproteinases-1 (TIMP‑1), procollagen-1 and monocyte chemoattractant protein-1 (MCP-1), as well as the number of F4/80-positive hepatic (Kupffer) cells, were significantly increased in the HFD group compared with the NC group, and they were reduced by nimesulide. In conclusion, COX-2 may emerge as a molecular target for preventing the development of NAFLD and insulin resistance in diet-related obesity.
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Affiliation(s)
- Shunsuke Tsujimoto
- Department of Genetic Medicine and Regenerative Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Science, Yonago, Tottori 683-8504, Japan
| | - Manabu Kishina
- Second Department of Internal Medicine, Tottori University, Yonago, Tottori 683-8504, Japan
| | - Masahiko Koda
- Second Department of Internal Medicine, Tottori University, Yonago, Tottori 683-8504, Japan
| | - Yasutaka Yamamoto
- Pharmaceutical Research Group II, Pharmacology Research Department, Pharmaceutical Development Research Laboratories, Tokyo 191‑8512, Japan
| | - Kohei Tanaka
- Department of Genetic Medicine and Regenerative Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Science, Yonago, Tottori 683-8504, Japan
| | - Yusuke Harada
- Department of Genetic Medicine and Regenerative Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Science, Yonago, Tottori 683-8504, Japan
| | - Akio Yoshida
- Department of Genetic Medicine and Regenerative Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Science, Yonago, Tottori 683-8504, Japan
| | - Ichiro Hisatome
- Department of Genetic Medicine and Regenerative Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Science, Yonago, Tottori 683-8504, Japan
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126
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Liangpunsakul S, Gao B. Alcohol and fat promote steatohepatitis: a critical role for fat-specific protein 27/CIDEC. J Investig Med 2016; 64:1078-81. [PMID: 27342423 DOI: 10.1136/jim-2016-000204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2016] [Indexed: 12/20/2022]
Abstract
Alcoholic liver disease (ALD) is a major public health problem worldwide and is the leading cause of end-stage liver disease. While the ultimate control of ALD will require the prevention of alcohol abuse, better understanding of the mechanisms of alcohol-induced liver injury may lead to treatments of fatty liver, alcoholic hepatitis, and prevention or delay of occurrence of cirrhosis. The elucidation and the discovery of several new concepts in ALD pathogenesis have raised our understanding on the complex mechanisms and the potential in developing the new strategies for therapeutic benefits. In this review, we provide the most up-to-date information on the basic molecular mechanisms focusing on the role of fat-specific protein 27/CIDEC in the pathogenesis of ALD.
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Affiliation(s)
- Suthat Liangpunsakul
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA Indiana University School of Medicine, Indianapolis, Indiana, USA Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, USA
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute of Alcohol Abuse and Alcoholism, Rockville, Maryland, USA
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127
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Park JE, Lee M, Mifflin R, Lee YK. Enhanced ethanol catabolism in orphan nuclear receptor SHP-null mice. Am J Physiol Gastrointest Liver Physiol 2016; 310:G799-807. [PMID: 26968209 PMCID: PMC4895871 DOI: 10.1152/ajpgi.00343.2015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 03/07/2016] [Indexed: 01/31/2023]
Abstract
Deficiency of the orphan nuclear hormone receptor small heterodimer partner (SHP, NR0B2) protects mice from diet-induced hepatic steatosis, in part, via repression of peroxisome proliferator-activated receptor (PPAR)-γ2 (Pparg2) gene expression. Alcoholic fatty liver diseases (AFLD) share many common pathophysiological features with non-AFLD. To study the role of SHP and PPARγ2 in AFLD, we used a strategy of chronic ethanol feeding plus a single binge ethanol feeding to challenge wild-type (WT) and SHP-null (SHP(-/-)) mice with ethanol. The ethanol feeding induced liver fat accumulation and mRNA expression of hepatic Pparg2 in WT mice, which suggests that a high level of PPARγ2 is a common driving force for fat accumulation induced by ethanol or a high-fat diet. Interestingly, ethanol-fed SHP(-/-) mice displayed hepatic fat accumulation similar to that of ethanol-fed WT mice, even though their Pparg2 expression level remained lower. Mortality of SHP(-/-) mice after ethanol binge feeding was significantly reduced and their acetaldehyde dehydrogenase (Aldh2) mRNA level was higher than that of their WT counterparts. After an intoxicating dose of ethanol, SHP(-/-) mice exhibited faster blood ethanol clearance and earlier wake-up time than WT mice. Higher blood acetate, the end product of ethanol metabolism, and lower acetaldehyde levels were evident in the ethanol-challenged SHP(-/-) than WT mice. Ethanol-induced inflammatory responses and lipid peroxidation were also lower in SHP(-/-) mice. The current data show faster ethanol catabolism and extra fat storage through conversion of acetate to acetyl-CoA before its release into the circulation in this ethanol-feeding model in SHP(-/-) mice.
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Affiliation(s)
| | | | | | - Yoon Kwang Lee
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, Ohio
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128
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Tan X, Cao Z, Li M, Xu E, Wang J, Xiao Y. TNF-α downregulates CIDEC via MEK/ERK pathway in human adipocytes. Obesity (Silver Spring) 2016; 24:1070-80. [PMID: 27062372 DOI: 10.1002/oby.21436] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 10/01/2015] [Accepted: 11/25/2015] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Cell death-inducing DFF45-like effector C (CIDEC) is a lipid droplet-coating protein that promotes triglyceride accumulation and inhibits lipolysis. TNF-α downregulates CIDEC levels to enhance basal lipolysis, whereas CIDEC overexpression could block this effect. This study aimed to investigate the signaling pathway of TNF-α-mediated CIDEC downregulation in human adipocytes. METHODS First CIDEC expression was detected in adipose tissue of lean and human subjects with obesity. Next, the temporal- and dose-dependent effects of TNF-α on CIDEC expression in human SW872 adipocytes were investigated. Selective inhibitors or RNAi or constitutively active MEK1 mutant was used to suppress or stimulate MEK/ERK cascade. Immunofluorescence and subcellular fractionation technique were used to study PPARγ redistribution after TNF-α treatment. Reporter assay was performed to confirm the direct effects of TNF-α on CIDEC transcription. RESULTS CIDEC expression decreased in adipose tissue of subjects with obesity and negatively correlated with adipose TNF-α levels and systemic lipolysis. TNF-α reduced CIDEC expression in vitro, but suppression of MEK/ERK cascade prevented TNF-α-mediated CIDEC downregulation. PPARγ, the transcription factor of CIDEC, was phosphorylated and redistributed by TNF-α in a MEK/ERK-dependent manner. Reporter assay confirmed that TNF-α reduced CIDEC transcription. CONCLUSIONS TNF-α downregulates CIDEC expression through phosphorylation and nuclear export of PPARγ by MEK/ERK cascade.
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Affiliation(s)
- Xinrui Tan
- Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi Province, People's Republic of China
| | - Zhenzhen Cao
- Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi Province, People's Republic of China
| | - Min Li
- Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi Province, People's Republic of China
| | - Erdi Xu
- Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi Province, People's Republic of China
| | - Jingjing Wang
- Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi Province, People's Republic of China
| | - Yanfeng Xiao
- Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi Province, People's Republic of China
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129
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Gao M, Ma Y, Alsaggar M, Liu D. Dual Outcomes of Rosiglitazone Treatment on Fatty Liver. AAPS JOURNAL 2016; 18:1023-31. [PMID: 27125895 DOI: 10.1208/s12248-016-9919-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 04/15/2016] [Indexed: 01/10/2023]
Abstract
In previous studies, it has been reported that rosiglitazone has opposing effects on nonalcoholic fatty liver disease. The purpose of the current study is to test the hypothesis that such opposing effects are related to different levels of peroxisome proliferator-activated receptor gamma (PPAR-γ) in the liver. Using a gene transfer approach and mice fed a high-fat diet (HFD) as an animal model, we demonstrate that mice with low levels of PPAR-γ expression in the liver are resistant to HFD-induced development of fatty liver when treated with rosiglitazone. Conversely, rosiglitazone treatment actually exacerbates liver steatosis in obese mice that have a higher level of PPAR-γ. Mechanistic studies show that an elevated hepatic PPAR-γ level is associated with an increased expression of genes responsible for lipid metabolism in the liver, particularly Cd36, Fabp4, and Mgat1. The concurrent transfer of these three genes into the mouse liver fully recapitulates the phenotypic change induced by the overexpression of PPAR-γ. These results provide evidence in support of the importance of PPAR-γ in the liver when rosiglitazone is considered for the treatment of fatty liver disease. Clinically, our results suggest the necessity of verifying PPAR-γ levels in the liver when rosiglitazone is considered as a treatment option, and indicate that the direct use of rosiglitazone for treatment of nonalcoholic fatty liver may not be desirable when the patient's PPAR-γ level in the liver is significantly elevated.
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Affiliation(s)
- Mingming Gao
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, 30602, USA
| | - Yongjie Ma
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, 30602, USA
| | - Mohammad Alsaggar
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, 30602, USA
| | - Dexi Liu
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, 30602, USA.
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130
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Ruan J, Zhang Y, Yuan J, Xin L, Xia J, Liu N, Mu Y, Chen Y, Yang S, Li K. A long-term high-fat, high-sucrose diet in Bama minipigs promotes lipid deposition and amyotrophy by up-regulating the myostatin pathway. Mol Cell Endocrinol 2016; 425:123-32. [PMID: 26850224 DOI: 10.1016/j.mce.2016.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 01/29/2016] [Accepted: 02/01/2016] [Indexed: 01/08/2023]
Abstract
Skeletal muscle is as an important regulator of blood glucose and glycolipid metabolism and is closely related to motor ability. The underlying mechanisms by which dietary ectopic lipids in skeletal muscle prevents muscle growth remain elusive. We utilized miniature Bama swine as a model to mimic human obesity using prolonged dietary induction. After 23 months on a high-fat, high-sucrose diet, metabolic disorders were induced in the animals, which exhibited increased body weight, extensive lipid deposition in the skeletal muscle and amyotrophy. Microarray profiles demonstrated the up-regulation of genes related to fat deposition and muscle growth inhibition. We outline a clear potential pathway that in combination with increased 11β-hydroxysteroid dehydrogenase type 1, promotes expression of a major inhibitor, myostatin, by converting corticosterone to cortisol, which leads to the growth inhibition of skeletal muscle. This research provides new insights into the treatment of muscle diseases induced by obesity.
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Affiliation(s)
- Jinxue Ruan
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China; Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Science, Jilin University, Changchun, 130012, PR China
| | - Yuanyuan Zhang
- College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China
| | - Jing Yuan
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China; College of Animal Science, Yangtz University, Jinzhou, 434023, Hubei, PR China
| | - Leilei Xin
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China
| | - Jihan Xia
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China
| | - Nan Liu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China; Agricutural Genomes Institute at Shenzhen, CAAS, Shenzhen, 518120, PR China
| | - Yulian Mu
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China
| | - Yaoxing Chen
- College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China
| | - Shulin Yang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China.
| | - Kui Li
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing, 100193, PR China; Agricutural Genomes Institute at Shenzhen, CAAS, Shenzhen, 518120, PR China
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131
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Conover CA, Bale LK, Nair KS. Comparative gene expression and phenotype analyses of skeletal muscle from aged wild-type and PAPP-A-deficient mice. Exp Gerontol 2016; 80:36-42. [PMID: 27086066 DOI: 10.1016/j.exger.2016.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 04/05/2016] [Accepted: 04/06/2016] [Indexed: 12/17/2022]
Abstract
Mice deficient in pregnancy-associated plasma protein-A (PAPP-A) have extended lifespan associated with decreased incidence and severity of degenerative diseases of age, such as cardiomyopathy and nephropathy. In this study, the effect of PAPP-A deficiency on aging skeletal muscle was investigated. Whole-genome expression profiling was performed on soleus muscles from 18-month-old wild-type (WT) and PAPP-A knock-out (KO) mice of the same sex and from the same litter ('womb-mates') to identify potential mechanisms of skeletal muscle aging and its retardation in PAPP-A deficiency. Top genes regulated in PAPP-A KO compared to WT muscle were associated with increased muscle function, increased metabolism, in particular lipid metabolism, and decreased stress. Fiber cross-sectional area was significantly increased in solei from PAPP-A KO mice. In vitro contractility experiments indicated increased specific force and decreased fatigue in solei from PAPP-A KO mice. Intrinsic mitochondrial oxidative capacity was significantly increased in skeletal muscle of aged PAPP-A KO compared to WT mice. Moreover, 18-month-old PAPP-A KO mice exhibited significantly enhanced endurance running on a treadmill. Thus, PAPP-A deficiency in mice is associated with indices of healthy skeletal muscle function with age.
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Affiliation(s)
- Cheryl A Conover
- Division of Endocrinology, Metabolism, and Nutrition, Endocrine Research Unit, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, United States.
| | - Laurie K Bale
- Division of Endocrinology, Metabolism, and Nutrition, Endocrine Research Unit, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, United States.
| | - K Sreekumaran Nair
- Division of Endocrinology, Metabolism, and Nutrition, Endocrine Research Unit, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, United States.
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132
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He B, Nohara K, Park N, Park YS, Guillory B, Zhao Z, Garcia JM, Koike N, Lee CC, Takahashi JS, Yoo SH, Chen Z. The Small Molecule Nobiletin Targets the Molecular Oscillator to Enhance Circadian Rhythms and Protect against Metabolic Syndrome. Cell Metab 2016; 23:610-21. [PMID: 27076076 PMCID: PMC4832569 DOI: 10.1016/j.cmet.2016.03.007] [Citation(s) in RCA: 359] [Impact Index Per Article: 44.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 02/01/2016] [Accepted: 03/14/2016] [Indexed: 02/07/2023]
Abstract
Dysregulation of circadian rhythms is associated with metabolic dysfunction, yet it is unclear whether enhancing clock function can ameliorate metabolic disorders. In an unbiased chemical screen using fibroblasts expressing PER2::Luc, we identified Nobiletin (NOB), a natural polymethoxylated flavone, as a clock amplitude-enhancing small molecule. When administered to diet-induced obese (DIO) mice, NOB strongly counteracted metabolic syndrome and augmented energy expenditure and locomotor activity in a Clock gene-dependent manner. In db/db mutant mice, the clock is also required for the mitigating effects of NOB on metabolic disorders. In DIO mouse liver, NOB enhanced clock protein levels and elicited pronounced gene expression remodeling. We identified retinoid acid receptor-related orphan receptors as direct targets of NOB, revealing a pharmacological intervention that enhances circadian rhythms to combat metabolic disease via the circadian gene network.
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Affiliation(s)
- Baokun He
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Kazunari Nohara
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Noheon Park
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Yong-Sung Park
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Bobby Guillory
- Division of Endocrinology, Diabetes and Metabolism, MCL, Center for Translational Research in Inflammatory Diseases, Michael E. DeBakey Veterans Affairs Medical Center, and Department of Medicine, and Molecular and Cell Biology, Dan L. Duncan Cancer Center, Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Zhaoyang Zhao
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Jose M Garcia
- Division of Endocrinology, Diabetes and Metabolism, MCL, Center for Translational Research in Inflammatory Diseases, Michael E. DeBakey Veterans Affairs Medical Center, and Department of Medicine, and Molecular and Cell Biology, Dan L. Duncan Cancer Center, Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA
| | - Nobuya Koike
- Department of Physiology and Systems Bioscience, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Cheng Chi Lee
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Joseph S Takahashi
- Department of Neuroscience, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Howard Hughes Medical Institute, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Seung-Hee Yoo
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Zheng Chen
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, 6431 Fannin Street, Houston, TX 77030, USA.
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133
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Tamori Y, Tateya S, Ijuin T, Nishimoto Y, Nakajima S, Ogawa W. Negatively-charged residues in the polar carboxy-terminal region in FSP27 are indispensable for expanding lipid droplets. FEBS Lett 2016; 590:750-9. [PMID: 26921608 DOI: 10.1002/1873-3468.12114] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 02/03/2016] [Accepted: 02/23/2016] [Indexed: 12/13/2022]
Abstract
FSP27 has an important role in large lipid droplet (LD) formation because it exchanges lipids at the contact site between LDs. In the present study, we clarify that the amino-terminal domain of FSP27 (amino acids 1-130) is dispensable for LD enlargement, although it accelerates LD growth. LD expansion depends on the carboxy-terminal domain of FSP27 (amino acids 131-239). Especially, the negative charge of the acidic residues (D215, E218, E219 and E220) in the polar carboxy-terminal region (amino acids 202-239) is essential for the enlargement of LD. We propose that the carboxy-terminal domain of FSP27 has a crucial role in LD expansion, whereas the amino-terminal domain only has a supportive role.
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Affiliation(s)
- Yoshikazu Tamori
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Chibune General Hospital, Osaka, Japan.,Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan
| | - Sanshiro Tateya
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan.,Division of Diabetes, Department of Internal Medicine, Kakogawa West City Hospital, Japan
| | - Takeshi Ijuin
- Division of Biochemistry, Department of Molecular and Cellular Biology, Kobe University Graduate School of Medicine, Japan
| | - Yuki Nishimoto
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan
| | - Shinsuke Nakajima
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan
| | - Wataru Ogawa
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Japan
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134
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Xu W, Wu L, Yu M, Chen FJ, Arshad M, Xia X, Ren H, Yu J, Xu L, Xu D, Li JZ, Li P, Zhou L. Differential Roles of Cell Death-inducing DNA Fragmentation Factor-α-like Effector (CIDE) Proteins in Promoting Lipid Droplet Fusion and Growth in Subpopulations of Hepatocytes. J Biol Chem 2016; 291:4282-93. [PMID: 26733203 DOI: 10.1074/jbc.m115.701094] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Indexed: 01/21/2023] Open
Abstract
Lipid droplets (LDs) are dynamic subcellular organelles whose growth is closely linked to obesity and hepatic steatosis. Cell death-inducing DNA fragmentation factor-α-like effector (CIDE) proteins, including Cidea, Cideb, and Cidec (also called Fsp27), play important roles in lipid metabolism. Cidea and Cidec are LD-associated proteins that promote atypical LD fusion in adipocytes. Here, we find that CIDE proteins are all localized to LD-LD contact sites (LDCSs) and promote lipid transfer, LD fusion, and growth in hepatocytes. We have identified two types of hepatocytes, one with small LDs (small LD-containing hepatocytes, SLHs) and one with large LDs (large LD-containing hepatocytes, LLHs) in the liver. Cideb is localized to LDCSs and promotes lipid exchange and LD fusion in both SLHs and LLHs, whereas Cidea and Cidec are specifically localized to the LDCSs and promote lipid exchange and LD fusion in LLHs. Cideb-deficient SLHs have reduced LD sizes and lower lipid exchange activities. Fasting dramatically induces the expression of Cidea/Cidec and increases the percentage of LLHs in the liver. The majority of the hepatocytes from the liver of obese mice are Cidea/Cidec-positive LLHs. Knocking down Cidea or Cidec significantly reduced lipid storage in the livers of obese animals. Our data reveal that CIDE proteins play differential roles in promoting LD fusion and lipid storage; Cideb promotes lipid storage under normal diet conditions, whereas Cidea and Cidec are responsible for liver steatosis under fasting and obese conditions.
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Affiliation(s)
- Wenyi Xu
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lizhen Wu
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Miao Yu
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Feng-Jung Chen
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Muhammad Arshad
- the Department of Bioinformatics and Biotechnology, International Islamic University, Islamabad 44000, Pakistan
| | - Xiayu Xia
- the Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences, Beijing 100021, China
| | - Hao Ren
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jinhai Yu
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Li Xu
- the Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China, and
| | - Dijin Xu
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - John Zhong Li
- the Jiangsu Province Key Laboratory of Human Functional Genomics, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanjing Medical University, Nanjing 210029, China
| | - Peng Li
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China,
| | - Linkang Zhou
- From the MOE Key Laboratory of Bioinformatics and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China,
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135
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Ham JR, Lee HI, Choi RY, Sim MO, Seo KI, Lee MK. Anti-steatotic and anti-inflammatory roles of syringic acid in high-fat diet-induced obese mice. Food Funct 2016; 7:689-697. [DOI: 10.1039/c5fo01329a] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2023]
Abstract
This study examined the effects of syringic acid (SA) on obese diet-induced hepatic dysfunction.
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Affiliation(s)
- Ju Ri Ham
- Department of Food and Nutrition
- Sunchon National University
- Suncheon
- Korea
| | - Hae-In Lee
- Mokpo Marin Food-Industry Research Center
- Mokpo
- Korea
| | - Ra-Yeong Choi
- Department of Food and Nutrition
- Sunchon National University
- Suncheon
- Korea
| | - Mi-Ok Sim
- Jeollanamdo Development Institute of Korean Traditional Medicine
- Jangheung
- Korea
| | - Kwon-Il Seo
- Department of Biotechnology
- Dong-A University
- Busan
- Korea
| | - Mi-Kyung Lee
- Department of Food and Nutrition
- Sunchon National University
- Suncheon
- Korea
- Suncheon Research Center for Natural Medicines
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136
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Zhu YX, Zhang ML, Zhong Y, Wang C, Jia WP. Modulation Effect of Peroxisome Proliferator-Activated Receptor Agonists on Lipid Droplet Proteins in Liver. J Diabetes Res 2016; 2016:8315454. [PMID: 26770990 PMCID: PMC4684860 DOI: 10.1155/2016/8315454] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 06/02/2015] [Accepted: 07/01/2015] [Indexed: 12/14/2022] Open
Abstract
Peroxisome proliferator-activated receptor (PPAR) agonists are used for treating hyperglycemia and type 2 diabetes. However, the mechanism of action of these agonists is still under investigation. The lipid droplet-associated proteins FSP27/CIDEC and LSDP5, regulated directly by PPARγ and PPARα, are associated with hepatic steatosis and insulin sensitivity. Here, we evaluated the expression levels of FSP27/CIDEC and LSDP5 and the regulation of these proteins by consumption of a high-fat diet (HFD) or administration of PPAR agonists. Mice with diet-induced obesity were treated with the PPARγ or PPARα agonist, pioglitazone or fenofibrate, respectively. Liver tissues from db/db diabetic mice and human were also collected. Interestingly, FSP27/CIEDC was expressed in mouse and human livers and was upregulated in obese C57BL/6J mice. Fenofibrate treatment decreased hepatic triglyceride (TG) content and FSP27/CIDEC protein expression in mice fed an HFD diet. In mice, LSDP5 was not detected, even in the context of insulin resistance or treatment with PPAR agonists. However, LSDP5 was highly expressed in humans, with elevated expression observed in the fatty liver. We concluded that fenofibrate greatly decreased hepatic TG content and FSP27/CIDEC protein expression in mice fed an HFD, suggesting a potential regulatory role for fenofibrate in the amelioration of hepatic steatosis.
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Affiliation(s)
- Yun-Xia Zhu
- Department of Geriatrics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
| | - Ming-Liang Zhang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
| | - Yuan Zhong
- Department of Geriatrics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
| | - Chen Wang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
- Shanghai Key Laboratory of Diabetes Mellitus, 600 Yishan Road, Shanghai 200233, China
- Shanghai Diabetes Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
- *Chen Wang:
| | - Wei-Ping Jia
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
- Shanghai Key Laboratory of Diabetes Mellitus, 600 Yishan Road, Shanghai 200233, China
- Shanghai Diabetes Institute, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China
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WANG MIN, ZHAO SHUIPING, TAN MINGYUE. bZIP transmembrane transcription factor CREBH: Potential role in non-alcoholic fatty liver disease (Review). Mol Med Rep 2015; 13:1455-62. [DOI: 10.3892/mmr.2015.4749] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 12/02/2015] [Indexed: 11/06/2022] Open
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Urrutia RA, Kalinec F. Biology and pathobiology of lipid droplets and their potential role in the protection of the organ of Corti. Hear Res 2015; 330:26-38. [PMID: 25987503 PMCID: PMC5391798 DOI: 10.1016/j.heares.2015.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 12/20/2022]
Abstract
The current review article seeks to extend our understanding on the role of lipid droplets within the organ of Corti. In addition to presenting an overview of the current information about the origin, structure and function of lipid droplets we draw inferences from the collective body of knowledge about this cellular organelle to build a conceptual framework to better understanding their role in auditory function. This conceptual model considers that lipid droplets play a significant role in the synthesis, storage, and release of lipids and proteins for energetic use and/or modulating cell signaling pathways. We describe the role and mechanism by which LD play a role in human diseases, and we also review emerging data from our laboratory revealing the potential role of lipid droplets from Hensen cells in the auditory organ. We suggest that lipid droplets might help to develop rapidly and efficiently the resolution phase of inflammatory responses in the mammalian cochlea, preventing inflammatory damage of the delicate inner ear structures and, consequently, sensorineural hearing loss.
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Affiliation(s)
- Raul A Urrutia
- Epigenetics and Chromatin Dynamics Laboratory, Translational Epigenomic Program, Center for Individualized Medicine (CIM) Mayo Clinic, Rochester, MN 55905, USA
| | - Federico Kalinec
- Laboratory of Auditory Cell Biology, Department of Head & Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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Barneda D, Planas-Iglesias J, Gaspar ML, Mohammadyani D, Prasannan S, Dormann D, Han GS, Jesch SA, Carman GM, Kagan V, Parker MG, Ktistakis NT, Klein-Seetharaman J, Dixon AM, Henry SA, Christian M. The brown adipocyte protein CIDEA promotes lipid droplet fusion via a phosphatidic acid-binding amphipathic helix. eLife 2015; 4:e07485. [PMID: 26609809 PMCID: PMC4755750 DOI: 10.7554/elife.07485] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 11/25/2015] [Indexed: 12/22/2022] Open
Abstract
Maintenance of energy homeostasis depends on the highly regulated storage and release of triacylglycerol primarily in adipose tissue, and excessive storage is a feature of common metabolic disorders. CIDEA is a lipid droplet (LD)-protein enriched in brown adipocytes promoting the enlargement of LDs, which are dynamic, ubiquitous organelles specialized for storing neutral lipids. We demonstrate an essential role in this process for an amphipathic helix in CIDEA, which facilitates embedding in the LD phospholipid monolayer and binds phosphatidic acid (PA). LD pairs are docked by CIDEA trans-complexes through contributions of the N-terminal domain and a C-terminal dimerization region. These complexes, enriched at the LD–LD contact site, interact with the cone-shaped phospholipid PA and likely increase phospholipid barrier permeability, promoting LD fusion by transference of lipids. This physiological process is essential in adipocyte differentiation as well as serving to facilitate the tight coupling of lipolysis and lipogenesis in activated brown fat. DOI:http://dx.doi.org/10.7554/eLife.07485.001 If other energy sources become unavailable, cells fall back on stores of fatty molecules called lipids. These are held in membrane-enclosed compartments in the cell called lipid droplets, which in mammals are particularly abundant in fat cells called adipocytes. There are two main types of adipocytes: white adipocytes have a single giant lipid droplet, whereas brown adipocytes contain many smaller droplets. Proteins embedded in the membrane that surrounds a lipid droplet help to control the droplet’s growth and when it releases lipids. For example, a protein called CIDEA, which is only found in brown adipocytes, helps lipid droplets to grow by enabling one droplet to transfer its contents to another droplet. However, little is known about how this occurs. By combining cell biology, biophysical and computer modelling approaches, Barneda et al. investigated how normal and mutant forms of CIDEA affect the growth of lipid droplets. These experiments identified a helix in the structure of CIDEA that embeds it in the membrane, from where it can then interact with CIDEA proteins on other lipid droplets to hold the droplets together. In addition, the helix interacts with a molecule in the lipid droplet membrane called phosphatidic acid. Barneda et al. suggest that this interaction helps to transfer the contents of one droplet to another by making it easier for lipids to move through the droplets’ membranes. The next challenge is to characterize the mechanisms that control CIDEA activity to influence the formation of the multiple lipid droplets that distinguish brown and BRITE (brown-in-white) adipocytes from white adipocytes. The lipid droplets in brown adipocytes are an important target for research to combat obesity, due to the 'burning' rather than storing of lipids that occurs in these cells. DOI:http://dx.doi.org/10.7554/eLife.07485.002
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Affiliation(s)
- David Barneda
- Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom
| | | | - Maria L Gaspar
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Dariush Mohammadyani
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, United States
| | - Sunil Prasannan
- Department of Chemistry, University of Warwick, Coventry, United Kingdom
| | - Dirk Dormann
- Microscopy Facility, MRC Clinical Sciences Centre, Imperial College London, London, United Kingdom
| | - Gil-Soo Han
- Department of Food Science, Rutgers Center for Lipid Research, Rutgers University, New Brunswick, United States
| | - Stephen A Jesch
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - George M Carman
- Department of Food Science, Rutgers Center for Lipid Research, Rutgers University, New Brunswick, United States
| | - Valerian Kagan
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, United States
| | - Malcolm G Parker
- Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom
| | | | - Judith Klein-Seetharaman
- Warwick Medical School, University of Warwick, Coventry, United Kingdom.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, United States
| | - Ann M Dixon
- Department of Chemistry, University of Warwick, Coventry, United Kingdom
| | - Susan A Henry
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Mark Christian
- Institute of Reproductive and Developmental Biology, Imperial College London, London, United Kingdom.,Warwick Medical School, University of Warwick, Coventry, United Kingdom
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140
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Nuotio-Antar AM, Poungvarin N, Li M, Schupp M, Mohammad M, Gerard S, Zou F, Chan L. FABP4-Cre Mediated Expression of Constitutively Active ChREBP Protects Against Obesity, Fatty Liver, and Insulin Resistance. Endocrinology 2015; 156:4020-32. [PMID: 26248218 PMCID: PMC4606753 DOI: 10.1210/en.2015-1210] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Carbohydrate response element binding protein (ChREBP) regulates cellular glucose and lipid homeostasis. Although ChREBP is highly expressed in many key metabolic tissues, the role of ChREBP in most of those tissues and the consequent effects on whole-body glucose and lipid metabolism are not well understood. Therefore, we generated a transgenic mouse that overexpresses a constitutively active ChREBP isoform under the control of the fatty acid binding protein 4-Cre-driven promoter (FaChOX). Weight gain was blunted in male, but not female, FaChOX mice when placed on either a normal chow diet or an obesogenic Western diet. Respiratory exchange ratios were increased in Western diet-fed FaChOX mice, indicating a shift in whole-body substrate use favoring carbohydrate metabolism. Western diet-fed FaChOX mice showed improved insulin sensitivity and glucose tolerance in comparison with controls. Hepatic triglyceride content was reduced in Western diet-fed FaChOX mice in comparison with controls, suggesting protection from fatty liver. Epididymal adipose tissue exhibited differential expression of genes involved in differentiation, browning, metabolism, lipid homeostasis, and inflammation between Western diet-fed FaChOX mice and controls. Our findings support a role for ChREBP in modulating adipocyte differentiation and adipose tissue metabolism and inflammation as well as consequent risks for obesity and insulin resistance.
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Affiliation(s)
- Alli M Nuotio-Antar
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Naravat Poungvarin
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Ming Li
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Michael Schupp
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Mahmoud Mohammad
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Sarah Gerard
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Fang Zou
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
| | - Lawrence Chan
- Diabetes and Endocrinology Research Center (A.M.N.-A., N.P., M.L., L.C.), Department of Medicine, and Children's Nutrition Research Center (A.M.N.-A., M.M., S.G., F.Z.), Department of Pediatrics, Baylor College of Medicine, Houston, Texas 77030; and Charité University School of Medicine (M.S.), Institute of Pharmacology, Center for Cardiovascular Research, 10115 Berlin, Germany
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141
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Kobayashi K, Tanaka T, Okada S, Morimoto Y, Matsumura S, Manio MCC, Inoue K, Kimura K, Yagi T, Saito Y, Fushiki T, Inoue H, Matsumoto M, Nabeshima YI. Hepatocyte β-Klotho regulates lipid homeostasis but not body weight in mice. FASEB J 2015; 30:849-62. [PMID: 26514166 DOI: 10.1096/fj.15-274449] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 10/19/2015] [Indexed: 01/26/2023]
Abstract
β-Klotho (β-Kl), a transmembrane protein expressed in the liver, pancreas, adipose tissues, and brain, is essential for feedback suppression of hepatic bile acid synthesis. Because bile acid is a key regulator of lipid and energy metabolism, we hypothesized potential and tissue-specific roles of β-Kl in regulating plasma lipid levels and body weight. By crossing β-kl(-/-) mice with newly developed hepatocyte-specific β-kl transgenic (Tg) mice, we generated mice expressing β-kl solely in hepatocytes (β-kl(-/-)/Tg). Gene expression, metabolomic, and in vivo flux analyses consistently revealed that plasma level of cholesterol, which is over-excreted into feces as bile acids in β-kl(-/-), is maintained in β-kl(-/-) mice by enhanced de novo cholesterogenesis. No compensatory increase in lipogenesis was observed, despite markedly decreased plasma triglyceride. Along with enhanced bile acid synthesis, these lipid dysregulations in β-kl(-/-) were completely reversed in β-kl(-/-)/Tg mice. In contrast, reduced body weight and resistance to diet-induced obesity in β-kl(-/-) mice were not reversed by hepatocyte-specific restoration of β-Kl expression. We conclude that β-Kl in hepatocytes is necessary and sufficient for lipid homeostasis, whereas nonhepatic β-Kl regulates energy metabolism. We further demonstrate that in a condition with excessive cholesterol disposal, a robust compensatory mechanism maintains cholesterol levels but not triglyceride levels in mice.
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Affiliation(s)
- Kanako Kobayashi
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Tomohiro Tanaka
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Sadanori Okada
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Yuki Morimoto
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Shigenobu Matsumura
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Mark Christian C Manio
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Kazuo Inoue
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Kumi Kimura
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Takashi Yagi
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Yoshihiko Saito
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Tohru Fushiki
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Hiroshi Inoue
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Michihiro Matsumoto
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Yo-Ichi Nabeshima
- *Laboratory of Molecular Life Science, Foundation for Biomedical Research and Innovation, Kobe, Hyogo, Japan; Medical Innovation Center and Department of Pathology and Tumor Biology, Graduate School of Medicine, and Laboratory of Nutrition Chemistry, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan; First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, Japan; Department of Physiology and Metabolism, Brain/Liver Interface Medicine Research Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan; and Department of Molecular Metabolic Regulation, Diabetes Research Center, Research Institute, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
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Carr RM, Ahima RS. Pathophysiology of lipid droplet proteins in liver diseases. Exp Cell Res 2015; 340:187-92. [PMID: 26515554 DOI: 10.1016/j.yexcr.2015.10.021] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/21/2015] [Accepted: 10/23/2015] [Indexed: 02/07/2023]
Abstract
Cytosolic lipid droplets (LDs) are present in most cell types, and consist of a core comprising neutral lipids, mainly triglycerides and sterol esters, surrounded by a monolayer of phospholipids. LDs are heterogeneous in their structure, chemical composition, and tissue distribution. LDs are coated by several proteins, including perilipins and other structural proteins, lipogenic enzymes, lipases and membrane-trafficking proteins. Five proteins of the perilipin (PLIN) family (PLIN1 (perilipin), PLIN2 (adipose differentiation-related protein), PLIN3 (tail-interacting protein of 47kDa), PLIN4 (S3-12), and PLIN5 (myocardial lipid droplet protein)), are associated with LD formation. More recently, the CIDE family of proteins, hypoxia-inducible protein 2 (HIG2), and patanin-like phospholipase domain-containing 3 (PNPLA3) have also gained attention in hepatic LD biology. Evidence suggests that LD proteins are involved in the pathophysiology of fatty liver diseases characterized by excessive lipid accumulation in hepatocytes. This review article will focus on how hepatic LDs and their associated proteins are involved in the pathogenesis of three chronic liver conditions: hepatitis C virus infection, non-alcoholic fatty liver disease, and alcoholic liver disease.
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Affiliation(s)
- Rotonya M Carr
- Department of Medicine, Gastroenterology and Hepatology Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Rexford S Ahima
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
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143
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Xu MJ, Cai Y, Wang H, Altamirano J, Chang B, Bertola A, Odena G, Lu J, Tanaka N, Matsusue K, Matsubara T, Mukhopadhyay P, Kimura S, Pacher P, Gonzalez FJ, Bataller R, Gao B. Fat-Specific Protein 27/CIDEC Promotes Development of Alcoholic Steatohepatitis in Mice and Humans. Gastroenterology 2015; 149:1030-41.e6. [PMID: 26099526 PMCID: PMC4584194 DOI: 10.1053/j.gastro.2015.06.009] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 05/29/2015] [Accepted: 06/09/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Alcoholic steatohepatitis (ASH) is the progressive form of alcoholic liver disease and may lead to cirrhosis and hepatocellular carcinoma. We studied mouse models and human tissues to identify molecules associated with ASH progression and focused on the mouse fat-specific protein 27 (FSP-27)/human cell death-inducing DFF45-like effector C (CIDEC) protein, which is expressed in white adipose tissues and promotes formation of fat droplets. METHODS C57BL/6N mice or mice with hepatocyte-specific disruption of Fsp27 (Fsp27(Hep-/-) mice) were fed the Lieber-Decarli ethanol liquid diet (5% ethanol) for 10 days to 12 weeks, followed by 1 or multiple binges of ethanol (5 or 6 g/kg) during the chronic feeding. Some mice were given an inhibitor (GW9662) of peroxisome proliferator-activated receptor γ (PPARG). Adenoviral vectors were used to express transgenes or small hairpin (sh) RNAs in cultured hepatocytes and in mice. Liver tissue samples were collected from ethanol-fed mice or from 31 patients with alcoholic hepatitis (AH) with biopsy-proved ASH and analyzed histologically and immunohistochemically and by transcriptome, immunoblotting, and real-time PCR analyses. RESULTS Chronic-plus-binge ethanol feeding of mice, which mimics the drinking pattern of patients with AH, produced severe ASH and mild fibrosis. Microarray analyses revealed similar alterations in expression of many hepatic genes in ethanol-fed mice and humans with ASH, including up-regulation of mouse Fsp27 (also called Cidec) and human CIDEC. Fsp27(Hep-/-) mice and mice given injections of adenovirus-Fsp27shRNA had markedly reduced ASH following chronic-plus-binge ethanol feeding. Inhibition of PPARG and cyclic AMP-responsive element binding protein H (CREBH) prevented the increases in Fsp27α and FSP27β mRNAs, respectively, and reduced liver injury in this chronic-plus-binge ethanol feeding model. Overexpression of FSP27 and ethanol exposure had synergistic effects in inducing production of mitochondrial reactive oxygen species and damage to hepatocytes in mice. Hepatic CIDEC mRNA expression was increased in patients with AH and correlated with the degree of hepatic steatosis and disease severity including mortality. CONCLUSIONS In mice, chronic-plus-binge ethanol feeding induces ASH that mimics some histological and molecular features observed in patients with AH. Hepatic expression of FSP27/CIDEC is highly up-regulated in mice following chronic-plus-binge ethanol feeding and in patients with AH; this up-regulation contributes to alcohol-induced liver damage.
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Affiliation(s)
- Ming-Jiang Xu
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland; Department of Physiology and Pathophysiology, School of Basic Medical Science, Peking University, Beijing, China
| | - Yan Cai
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland; Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Hua Wang
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland; Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - José Altamirano
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) and Liver Unit-Internal Medicine Department, Vall d'Hebron Hospital, Vall d'Hebron Institut de Recerca, Barcelona, Spain
| | - Binxia Chang
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| | - Adeline Bertola
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| | - Gemma Odena
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Jim Lu
- GoPath Diagnostics, LLC, Chicago, Illinois
| | - Naoki Tanaka
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Kimihiko Matsusue
- Faculty of Pharmaceutical Science, Fukuoka University, Fukuoka, Japan
| | - Tsutomu Matsubara
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Partha Mukhopadhyay
- Section of Oxidative Stress and Tissue Injury, Laboratory of Physiological Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| | - Shioko Kimura
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Pal Pacher
- Section of Oxidative Stress and Tissue Injury, Laboratory of Physiological Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| | - Frank J Gonzalez
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Ramon Bataller
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) and Liver Unit-Internal Medicine Department, Vall d'Hebron Hospital, Vall d'Hebron Institut de Recerca, Barcelona, Spain; Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Department of Medicine, Division of Gastroenterology and Hepatology, University of North Carolina, Chapel Hill, North Carolina
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland.
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144
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Stinkens R, Goossens GH, Jocken JWE, Blaak EE. Targeting fatty acid metabolism to improve glucose metabolism. Obes Rev 2015; 16:715-57. [PMID: 26179344 DOI: 10.1111/obr.12298] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/23/2015] [Accepted: 05/10/2015] [Indexed: 12/15/2022]
Abstract
Disturbances in fatty acid metabolism in adipose tissue, liver, skeletal muscle, gut and pancreas play an important role in the development of insulin resistance, impaired glucose metabolism and type 2 diabetes mellitus. Alterations in diet composition may contribute to prevent and/or reverse these disturbances through modulation of fatty acid metabolism. Besides an increased fat mass, adipose tissue dysfunction, characterized by an altered capacity to store lipids and an altered secretion of adipokines, may result in lipid overflow, systemic inflammation and excessive lipid accumulation in non-adipose tissues like liver, skeletal muscle and the pancreas. These impairments together promote the development of impaired glucose metabolism, insulin resistance and type 2 diabetes mellitus. Furthermore, intrinsic functional impairments in either of these organs may contribute to lipotoxicity and insulin resistance. The present review provides an overview of fatty acid metabolism-related pathways in adipose tissue, liver, skeletal muscle, pancreas and gut, which can be targeted by diet or food components, thereby improving glucose metabolism.
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Affiliation(s)
- R Stinkens
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - G H Goossens
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - J W E Jocken
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - E E Blaak
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
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145
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Ikura Y, Caldwell SH. Lipid droplet-associated proteins in alcoholic liver disease: a potential linkage with hepatocellular damage. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:8699-8708. [PMID: 26464614 PMCID: PMC4583846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 07/29/2015] [Indexed: 06/05/2023]
Abstract
Steatosis is a characteristic morphological change of alcoholic liver disease, but its pathologic significance is still obscure. Regardless of cell types, intracellular lipid droplets are coated with a phospholipid monolayer, on which many kinds of lipid droplet-associated proteins are present. These proteins, such as the perilipin family of proteins and the cell death inducing DNA fragmentation factor (DFF) 45-like effectors, are recognized to play important roles in lipid metabolism in the physiological settings. In addition, recent lipidology studies have revealed that expression of the lipid droplet-associated proteins possibly participate in the pathologic processes of many metabolic disorders, including fatty liver and insulin resistance. Hence, controlling protein expressions is expected to offer novel therapeutic options. In this review, we summarize collected data concerning the potential contribution of the lipid droplet-associated proteins to the development of alcoholic fatty liver. Without exception, existing data indicates that the lipid droplet-associated proteins, especially the perilipin family proteins, are important factors in alcoholic fatty liver. These proteins exert a prosteatotic effect, and their expression is closely associated with lipotoxicity based on endoplasmic reticulum stress and oxidative injury. Although suppression of their expression may be beneficial, careful consideration is required because these proteins simultaneously function as protective factors against lipotoxicity.
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Affiliation(s)
- Yoshihiro Ikura
- Department of Pathology, Takatsuki General Hospital1-3-13, Kosobecho, Takatsuki 569-1192, Japan
| | - Stephen H Caldwell
- Division of Gastroenterology and Hepatology, University of VirginiaCharlottesville, Virginia 22908-0708, USA
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146
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147
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Soni NK, Nookaew I, Sandberg AS, Gabrielsson BG. Eicosapentaenoic and docosahexaenoic acid-enriched high fat diet delays the development of fatty liver in mice. Lipids Health Dis 2015; 14:74. [PMID: 26193881 PMCID: PMC4509768 DOI: 10.1186/s12944-015-0072-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/01/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Low hepatic content of n-3 PUFA has been associated with NAFLD in humans. Whether this is associated with reduced dietary intake or increased turnover of these FA is not clear. We have here investigated the effects of dietary fat quality on hepatic lipid storage and transcriptomics over time. AIM To investigate the effects of quality of fat in a high fat diet (HFD) over time on hepatic lipid storage and liver transcriptomics. METHODS AND RESULTS Male C57BL/6J mice were fed control, HFD-eicosapentaenoic acid (EPA)/ docosahexaenoic acid (DHA) or HFD-corn oil diet for 8 or 12 weeks. Body weight, body composition, plasma and hepatic triglyceride contents were measured. Hepatic transcriptomes were analysed by microarray followed by gene-set enrichment analyses. At 8 weeks, the HFD-corn oil mice had higher body weight and adipose depot mass than the HFD-EPA/DHA but there were no differences at 12 weeks. Hepatic triglyceride content was lower in HFD-EPA/DHA fed compared with the HFD-corn oil fed mice at both time-points. Enrichment analyses of the hepatic transcriptomes showed that lipid/fatty acid biosynthesis; transport and homeostasis were lower in the HFD-EPA/DHA fed compared with the HFD-corn oil fed mice. Genes encoding proteins associated to cytoplasmic lipid droplets were expressed at higher levels in livers from the HFD-corn oil compared to HFD-EPA/DHA mice. CONCLUSIONS Dietary EPA and DHA counteracted development of HFD-induced fatty liver. The liver transcriptome data implicate that the quality of dietary fat could modulate Ppar-related gene expression that in turn affects hepatic lipid storage and maintenance of metabolic health.
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Affiliation(s)
- Nikul K Soni
- Divisions of Food and Nutrition Science, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden.
| | - Intawat Nookaew
- The division of Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden. .,Present address: Comparative Genomics Group, Biosciences division, Oak Ridge National Library, Oak Ridge, TN, 37831, USA.
| | - Ann-Sofie Sandberg
- Divisions of Food and Nutrition Science, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden.
| | - Britt G Gabrielsson
- Divisions of Food and Nutrition Science, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden.
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148
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Haplotypes in the promoter region of the CIDEC gene associated with growth traits in Nanyang cattle. Sci Rep 2015; 5:12075. [PMID: 26189824 PMCID: PMC4648405 DOI: 10.1038/srep12075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 06/16/2015] [Indexed: 12/13/2022] Open
Abstract
Cell death-inducing DFFA-like effector c (CIDEC, also known as Fsp27) has emerged as an important regulator of metabolism associated with lipodystrophy, diabetes, and hepatic steatosis. It is required for unilocular lipid droplet formation and optimal energy storage. The mechanism between this gene and livestock growth traits, however, has yet to be reported. In this study, we found ten novel single nucleotide polymorphisms (SNPs) in the 5’ transcriptional region of CIDEC in Nanyang (NY) cattle, which are located in the recognition sequences (potential cis-acting elements) of 22 transcription factors, and the nine haplotypes represent nine different combinations of polymorphic potential cis-acting elements. The results indicated that individuals with the H8-H8 diplotype had heavier body weights and faster growth rates (P < 0.01) at 18th months than those with H1-H8. We evaluated the transcriptional activities of different haplotypes in vitro, the results were consistent with the association analysis. The H8 haplotype had 1.88-fold (P < 0.001) higher transcriptional activity than the H1 haplotype. We speculate that the haplotypes of the potential cis-acting elements may affect the transcriptional activity of CIDEC, thus affecting the growth traits of cattle. This information may be used in molecular marker-assisted selection of cattle breeding in the future.
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149
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Reynolds TH, Banerjee S, Sharma VM, Donohue J, Couldwell S, Sosinsky A, Frulla A, Robinson A, Puri V. Effects of a High Fat Diet and Voluntary Wheel Running Exercise on Cidea and Cidec Expression in Liver and Adipose Tissue of Mice. PLoS One 2015; 10:e0130259. [PMID: 26176546 PMCID: PMC4503728 DOI: 10.1371/journal.pone.0130259] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 05/19/2015] [Indexed: 11/19/2022] Open
Abstract
Cidea and Cidec play an important role in regulating triglyceride storage in liver and adipose tissue. It is not known if the Cidea and Cidec genes respond to a high fat diet (HFD) or exercise training, two interventions that alter lipid storage. The purpose of the present study was to determine the effect of a HFD and voluntary wheel running (WR) on Cidea and Cidec mRNA and protein expression in adipose tissue and liver of mice. A HFD promoted a significant increase in Cidea and Cidec mRNA levels in adipose tissue and liver. The increase in Cidea and Cidec mRNAs in adipose tissue and liver in response to a HFD was prevented by WR. Similar to the changes in Cidea mRNA, Cidea protein levels in adipose tissue significantly increased in response to a HFD, a process that was, again, prevented by WR. However, in adipose tissue the changes in Cidec mRNA did not correspond to the changes in Cidec protein levels, as a HFD decreased Cidec protein abundance. Interestingly, in adipose tissue Cidea protein expression was significantly related to body weight (R=.725), epididymal adipose tissue (EWAT) mass (R=.475) and insulin resistance (R=.706), whereas Cidec protein expression was inversely related to body weight (R=-.787), EWAT mass (R=-.706), and insulin resistance (R=-.679). Similar to adipose tissue, Cidea protein expression in liver was significantly related to body weight (R=.660), EWAT mass (R=.468), and insulin resistance (R=.599); however, unlike adipose tissue, Cidec protein levels in liver were not related to body weight or EWAT mass and only moderately associated with insulin resistance (R=-.422, P=0.051). Overall, our findings indicate that Cidea is highly associated with adiposity and insulin resistance, whereas Cidec is related to insulin sensitivity. The present study suggests that Cide proteins might play an important functional role in the development of obesity, hepatic steatosis, as well as the pathogenesis of type 2 diabetes.
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Affiliation(s)
- Thomas H. Reynolds
- Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, 12866, United States of America
- * E-mail:
| | - Sayani Banerjee
- Department of Medicine, Section of Endocrinology, Diabetes and Nutrition, Boston University, Boston, MA, 02118, United States of America
| | - Vishva Mitra Sharma
- Department of Medicine, Section of Endocrinology, Diabetes and Nutrition, Boston University, Boston, MA, 02118, United States of America
| | - Jacob Donohue
- Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, 12866, United States of America
| | - Sandrine Couldwell
- Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, 12866, United States of America
| | - Alexandra Sosinsky
- Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, 12866, United States of America
| | - Ashton Frulla
- Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, 12866, United States of America
| | - Allegra Robinson
- Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, NY, 12866, United States of America
| | - Vishwajeet Puri
- Department of Medicine, Section of Endocrinology, Diabetes and Nutrition, Boston University, Boston, MA, 02118, United States of America
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Leptin administration restores the altered adipose and hepatic expression of aquaglyceroporins improving the non-alcoholic fatty liver of ob/ob mice. Sci Rep 2015; 5:12067. [PMID: 26159457 PMCID: PMC4498231 DOI: 10.1038/srep12067] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 06/17/2015] [Indexed: 12/27/2022] Open
Abstract
Glycerol is an important metabolite for the control of lipid accumulation in white adipose tissue (WAT) and liver. We aimed to investigate whether exogenous administration of leptin improves features of non-alcoholic fatty liver disease (NAFLD) in leptin-deficient ob/ob mice via the regulation of AQP3 and AQP7 (glycerol channels mediating glycerol efflux in adipocytes) and AQP9 (aquaglyceroporin facilitating glycerol influx in hepatocytes). Twelve-week-old male wild type and ob/ob mice were divided in three groups as follows: control, leptin-treated (1 mg/kg/d) and pair-fed. Leptin deficiency was associated with obesity and NAFLD exhibiting an AQP3 and AQP7 increase in WAT, without changes in hepatic AQP9. Adipose Aqp3 and hepatic Aqp9 transcripts positively correlated with markers of adiposity and hepatic steatosis. Chronic leptin administration (4-weeks) was associated with improved body weight, whole-body adiposity, and hepatosteatosis of ob/ob mice and to a down-regulation of AQP3, AQP7 in WAT and an up-regulation of hepatic AQP9. Acute leptin stimulation in vitro (4-h) induced the mobilization of aquaglyceroporins towards lipid droplets (AQP3) and the plasma membrane (AQP7) in murine adipocytes. Our results show that leptin restores the coordinated regulation of fat-specific AQP7 and liver-specific AQP9, a step which might prevent lipid overaccumulation in WAT and liver in obesity.
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