1
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Xu L, Li L, Wu L, Li P, Chen FJ. CIDE proteins and their regulatory mechanisms in lipid droplet fusion and growth. FEBS Lett 2024; 598:1154-1169. [PMID: 38355218 DOI: 10.1002/1873-3468.14823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 12/19/2023] [Accepted: 01/04/2024] [Indexed: 02/16/2024]
Abstract
The cell death-inducing DFF45-like effector (CIDE) proteins, including Cidea, Cideb, and Cidec/Fsp27, regulate various aspects of lipid homeostasis, including lipid storage, lipolysis, and lipid secretion. This review focuses on the physiological roles of CIDE proteins based on studies on knockout mouse models and human patients bearing CIDE mutations. The primary cellular function of CIDE proteins is to localize to lipid droplets (LDs) and to control LD fusion and growth across different cell types. We propose a four-step process of LD fusion, characterized by (a) the recruitment of CIDE proteins to the LD surface and CIDE movement, (b) the enrichment and condensate formation of CIDE proteins to form LD fusion plates at LD-LD contact sites, (c) lipid transfer through lipid-permeable passageways within the fusion plates, and (d) the completion of LD fusion. Lastly, we outline CIDE-interacting proteins as regulatory factors, as well as their contribution in LD fusion.
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Affiliation(s)
- Li Xu
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Lizhen Li
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Lingzhi Wu
- College of Future Technology, Peking University, Beijing, China
| | - Peng Li
- State Key Laboratory of Membrane Biology and Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
- Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai, China
- Tianjian Laboratory of Advanced Biomedical Sciences, Zhengzhou University, China
| | - Feng-Jung Chen
- Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University, Shanghai, China
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2
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Zadoorian A, Du X, Yang H. Lipid droplet biogenesis and functions in health and disease. Nat Rev Endocrinol 2023:10.1038/s41574-023-00845-0. [PMID: 37221402 DOI: 10.1038/s41574-023-00845-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/25/2023] [Indexed: 05/25/2023]
Abstract
Ubiquitous yet unique, lipid droplets are intracellular organelles that are increasingly being recognized for their versatility beyond energy storage. Advances uncovering the intricacies of their biogenesis and the diversity of their physiological and pathological roles have yielded new insights into lipid droplet biology. Despite these insights, the mechanisms governing the biogenesis and functions of lipid droplets remain incompletely understood. Moreover, the causal relationship between the biogenesis and function of lipid droplets and human diseases is poorly resolved. Here, we provide an update on the current understanding of the biogenesis and functions of lipid droplets in health and disease, highlighting a key role for lipid droplet biogenesis in alleviating cellular stresses. We also discuss therapeutic strategies of targeting lipid droplet biogenesis, growth or degradation that could be applied in the future to common diseases, such as cancer, hepatic steatosis and viral infection.
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Affiliation(s)
- Armella Zadoorian
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Ximing Du
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia.
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3
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Gupta A, Balakrishnan B, Karki S, Slayton M, Jash S, Banerjee S, Grahn THM, Jambunathan S, Disney S, Hussein H, Kong D, Lowell BB, Natarajan P, Reddy UK, Gokce N, Sharma VM, Puri V. Human CIDEC transgene improves lipid metabolism and protects against high-fat diet-induced glucose intolerance in mice. J Biol Chem 2022; 298:102347. [PMID: 35963433 PMCID: PMC9472082 DOI: 10.1016/j.jbc.2022.102347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/08/2022] [Accepted: 07/20/2022] [Indexed: 11/12/2022] Open
Abstract
Cell death–inducing DNA fragmentation factor-like effector C (CIDEC) expression in adipose tissue positively correlates with insulin sensitivity in obese humans. Further, E186X, a single-nucleotide CIDEC variant is associated with lipodystrophy, hypertriglyceridemia, and insulin resistance. To establish the unknown mechanistic link between CIDEC and maintenance of systemic glucose homeostasis, we generated transgenic mouse models expressing CIDEC (Ad-CIDECtg) and CIDEC E186X variant (Ad-CIDECmut) transgene specifically in the adipose tissue. We found that Ad-CIDECtg but not Ad-CIDECmut mice were protected against high-fat diet-induced glucose intolerance. Furthermore, we revealed the role of CIDEC in lipid metabolism using transcriptomics and lipidomics. Serum triglycerides, cholesterol, and low-density lipoproteins were lower in high-fat diet-fed Ad-CIDECtg mice compared to their littermate controls. Mechanistically, we demonstrated that CIDEC regulates the enzymatic activity of adipose triglyceride lipase via interacting with its activator, CGI-58, to reduce free fatty acid release and lipotoxicity. In addition, we confirmed that CIDEC is indeed a vital regulator of lipolysis in adipose tissue of obese humans, and treatment with recombinant CIDEC decreased triglyceride breakdown in visceral human adipose tissue. Our study unravels a central pathway whereby adipocyte-specific CIDEC plays a pivotal role in regulating adipose lipid metabolism and whole-body glucose homeostasis. In summary, our findings identify human CIDEC as a potential ‘drug’ or a ‘druggable’ target to reverse obesity-induced lipotoxicity and glucose intolerance.
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Affiliation(s)
- Abhishek Gupta
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Bijinu Balakrishnan
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Shakun Karki
- Evans Department of Medicine and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
| | - Mark Slayton
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Sukanta Jash
- Alpert Medical school of Brown University, Brown University, RI, USA
| | - Sayani Banerjee
- Alpert Medical school of Brown University, Brown University, RI, USA
| | - Tan Hooi Min Grahn
- Division of Molecular Medicine and Gene Therapy, Lund Stem Cell Center, Lund University Hospital, Lund, Sweden
| | | | - Sarah Disney
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Hebaallaha Hussein
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Dong Kong
- Division of Endocrinology, Department of Pediatrics, F.M. Kirby Neurobiology Center, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Bradford B Lowell
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA; Program in Neuroscience, Harvard Medical School, Boston, MA, USA
| | | | - Umesh K Reddy
- Department of Biology, West Virginia State University, Institute, WV, USA
| | - Noyan Gokce
- Evans Department of Medicine and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
| | - Vishva M Sharma
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA.
| | - Vishwajeet Puri
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA.
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4
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Jash S, Banerjee S, Lee MJ, Farmer SR, Puri V. CIDEA Transcriptionally Regulates UCP1 for Britening and Thermogenesis in Human Fat Cells. iScience 2019; 20:73-89. [PMID: 31563853 PMCID: PMC6817690 DOI: 10.1016/j.isci.2019.09.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 08/02/2019] [Accepted: 09/10/2019] [Indexed: 12/16/2022] Open
Abstract
Our study identifies a transcriptional role of cell death-inducing DNA fragmentation factor-like effector A (CIDEA), a lipid-droplet-associated protein, whereby it regulates human adipocyte britening/beiging with consequences for the regulation of energy expenditure. The comprehensive transcriptome analysis revealed CIDEA's control over thermogenic function in brite/beige human adipocytes. In the absence of CIDEA, achieved by the modified dual-RNA-based CRISPR-Cas9nD10A system, adipocytes lost their britening capability, which was recovered upon CIDEA re-expression. Uncoupling protein 1 (UCP1), the most upregulated gene in brite human adipocytes, was suppressed in CIDEA knockout (KO) primary human adipocytes. Mechanistically, during induced britening, CIDEA shuttled from lipid droplets to the nucleus via an unusual nuclear bipartite signal in a concentration-dependent manner. In the nucleus, it specifically inhibited LXRα repression of UCP1 enhancer activity and strengthened PPARγ binding to UCP1 enhancer, hence driving UCP1 transcription. Overall, our study defines the role of CIDEA in increasing thermogenesis in human adipocytes.
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Affiliation(s)
- Sukanta Jash
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Sayani Banerjee
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA
| | - Mi-Jeong Lee
- Icahn School of Medicine, Mount Sinai, New York, NY, USA
| | - Stephen R Farmer
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
| | - Vishwajeet Puri
- Department of Biomedical Sciences and Diabetes Institute, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701, USA.
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5
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Carino A, Marchianò S, Biagioli M, Fiorucci C, Zampella A, Monti MC, Morretta E, Bordoni M, Di Giorgio C, Roselli R, Ricci P, Distrutti E, Fiorucci S. Transcriptome Analysis of Dual FXR and GPBAR1 Agonism in Rodent Model of NASH Reveals Modulation of Lipid Droplets Formation. Nutrients 2019; 11:nu11051132. [PMID: 31117231 PMCID: PMC6567134 DOI: 10.3390/nu11051132] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/10/2019] [Accepted: 05/15/2019] [Indexed: 12/12/2022] Open
Abstract
Non-alcoholic steatohepatitis (NASH) is a progressive, chronic, liver disease whose prevalence is growing worldwide. Despite several agents being under development for treating NASH, there are no drugs currently approved. The Farnesoid-x-receptor (FXR) and the G-protein coupled bile acid receptor 1 (GPBAR1), two bile acid activated receptors, have been investigated for their potential in treating NASH. Here we report that BAR502, a steroidal dual ligand for FXR/GPBAR1, attenuates development of clinical and liver histopathology features of NASH in mice fed a high fat diet (HFD) and fructose (F). By RNAseq analysis of liver transcriptome we found that BAR502 restores FXR signaling in the liver of mice feed HFD-F, and negatively regulates a cluster of genes including Srebf1 (Srepb1c) and its target genes-fatty acid synthase (Fasn) and Cell death-inducing DFF45-like effector (CIDE) genes, Cidea and Cidec-involved in lipid droplets formation and triglycerides storage in hepatocytes. Additionally, BAR502 increased the intestinal expression of Fgf15 and Glp1 and energy expenditure by white adipose tissues. Finally, exposure to BAR502 reshaped the intestinal microbiota by increasing the amount of Bacteroidaceae. In conclusion, we have shown that dual FXR/GPBAR1 agonism might have utility in treatment of NASH.
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Affiliation(s)
- Adriana Carino
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | - Silvia Marchianò
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | - Michele Biagioli
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | - Chiara Fiorucci
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | - Angela Zampella
- Department of Pharmacy, University of Naples Federico II, 80138 Naples, Italy.
| | | | - Elva Morretta
- Department of Pharmacy, University of Salerno, 84084 Fisciano, Italy.
| | - Martina Bordoni
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | - Cristina Di Giorgio
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | - Rosalinda Roselli
- Department of Pharmacy, University of Naples Federico II, 80138 Naples, Italy.
| | - Patrizia Ricci
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
| | | | - Stefano Fiorucci
- Department of Surgical and Biomedical Sciences, University of Perugia, 06132 Perugia, Italy.
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6
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Sans A, Bonnafous S, Rousseau D, Patouraux S, Canivet CM, Leclere PS, Tran-Van-Nhieu J, Luci C, Bailly-Maitre B, Xu X, Lee AH, Minehira K, Anty R, Tran A, Iannelli A, Gual P. The Differential Expression of Cide Family Members is Associated with Nafld Progression from Steatosis to Steatohepatitis. Sci Rep 2019; 9:7501. [PMID: 31097771 PMCID: PMC6522528 DOI: 10.1038/s41598-019-43928-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 05/03/2019] [Indexed: 01/22/2023] Open
Abstract
Improved understanding of the molecular mechanisms responsible for the progression from a “non-pathogenic” steatotic state to Non-Alcoholic Steatohepatitis is an important clinical requirement. The cell death-inducing DFF45 like effector (CIDE) family members (A, B and FSP27) regulate hepatic lipid homeostasis by controlling lipid droplet growth and/or VLDL production. However, CIDE proteins, particularly FSP27, have a dual role in that they also regulate cell death. We here report that the hepatic expression of CIDEA and FSP27 (α/β) was similarly upregulated in a dietary mouse model of obesity-mediated hepatic steatosis. In contrast, CIDEA expression decreased, but FSP27-β expression strongly increased in a dietary mouse model of steatohepatitis. The inverse expression pattern of CIDEA and FSP27β was amplified with the increasing severity of the liver inflammation and injury. In obese patients, the hepatic CIDEC2 (human homologue of mouse FSP27β) expression strongly correlated with the NAFLD activity score and liver injury. The hepatic expression of CIDEA tended to increase with obesity, but decreased with NAFLD severity. In hepatic cell lines, the downregulation of FSP27β resulted in the fractionation of lipid droplets, whereas its overexpression decreased the expression of the anti-apoptotic BCL2 marker. This, in turn, sensitized cells to apoptosis in response to TNF α and saturated fatty acid. Considered together, our animal, human and in vitro studies indicate that differential expression of FSP27β/CIDEC2 and CIDEA is related to NAFLD progression and liver injury.
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Affiliation(s)
- Arnaud Sans
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | - Stéphanie Bonnafous
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | | | - Stéphanie Patouraux
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | - Clémence M Canivet
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | | | - Jeanne Tran-Van-Nhieu
- HU Henri Mondor, Department of Pathology, AP-HP - Université Paris Est Créteil, Créteil, France
| | - Carmelo Luci
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France
| | | | - Xu Xu
- Weill Cornell Medicine, Department of Medicine, Division of Gastroenterology and Hepatology, New York, USA
| | - Ann-Hwee Lee
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, USA
| | - Kaori Minehira
- University of Lausanne, Department of Physiology, Lausanne, Switzerland
| | - Rodolphe Anty
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | - Albert Tran
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | - Antonio Iannelli
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.,Université Côte d'Azur, CHU, INSERM, U1065, C3M, Nice, France
| | - Philippe Gual
- Université Côte d'Azur, INSERM, U1065, C3M, Nice, France.
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7
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Slayton M, Gupta A, Balakrishnan B, Puri V. CIDE Proteins in Human Health and Disease. Cells 2019; 8:cells8030238. [PMID: 30871156 PMCID: PMC6468517 DOI: 10.3390/cells8030238] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/07/2019] [Accepted: 03/09/2019] [Indexed: 12/14/2022] Open
Abstract
Cell death-Inducing DNA Fragmentation Factor Alpha (DFFA)-like Effector (CIDE) proteins have emerged as lipid droplet-associated proteins that regulate fat metabolism. There are three members in the CIDE protein family—CIDEA, CIDEB, and CIDEC (also known as fat-specific protein 27 (FSP27)). CIDEA and FSP27 are primarily expressed in adipose tissue, while CIDEB is expressed in the liver. Originally, based upon their homology with DNA fragmentation factors, these proteins were identified as apoptotic proteins. However, recent studies have changed the perception of these proteins, redefining them as regulators of lipid droplet dynamics and fat metabolism, which contribute to a healthy metabolic phenotype in humans. Despite various studies in humans and gene-targeting studies in mice, the physiological roles of CIDE proteins remains elusive. This review will summarize the known physiological role and metabolic pathways regulated by the CIDE proteins in human health and disease.
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Affiliation(s)
- Mark Slayton
- Department of Biomedical Sciences and Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH 45701, USA.
| | - Abhishek Gupta
- Department of Biomedical Sciences and Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH 45701, USA.
| | - Bijinu Balakrishnan
- Department of Biomedical Sciences and Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH 45701, USA.
| | - Vishwajeet Puri
- Department of Biomedical Sciences and Diabetes Institute, Ohio University Heritage College of Osteopathic Medicine, Athens, OH 45701, USA.
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8
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Xu S, Zhang X, Liu P. Lipid droplet proteins and metabolic diseases. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1968-1983. [DOI: 10.1016/j.bbadis.2017.07.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/14/2017] [Accepted: 07/19/2017] [Indexed: 12/13/2022]
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9
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Abstract
Triglyceride molecules represent the major form of storage and transport of fatty acids within cells and in the plasma. The liver is the central organ for fatty acid metabolism. Fatty acids accrue in liver by hepatocellular uptake from the plasma and by de novo biosynthesis. Fatty acids are eliminated by oxidation within the cell or by secretion into the plasma within triglyceride-rich very low-density lipoproteins. Notwithstanding high fluxes through these pathways, under normal circumstances the liver stores only small amounts of fatty acids as triglycerides. In the setting of overnutrition and obesity, hepatic fatty acid metabolism is altered, commonly leading to the accumulation of triglycerides within hepatocytes, and to a clinical condition known as nonalcoholic fatty liver disease (NAFLD). In this review, we describe the current understanding of fatty acid and triglyceride metabolism in the liver and its regulation in health and disease, identifying potential directions for future research. Advances in understanding the molecular mechanisms underlying the hepatic fat accumulation are critical to the development of targeted therapies for NAFLD. © 2018 American Physiological Society. Compr Physiol 8:1-22, 2018.
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Affiliation(s)
- Michele Alves-Bezerra
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
| | - David E Cohen
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
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10
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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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11
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Wu J, Zhang L, Zhang J, Dai Y, Bian L, Song M, Russell A, Wang W. The genetic contribution of CIDEA polymorphisms, haplotypes and loci interaction to obesity in a Han Chinese population. Mol Biol Rep 2013; 40:5691-9. [PMID: 24057179 DOI: 10.1007/s11033-013-2671-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Accepted: 09/14/2013] [Indexed: 11/25/2022]
Abstract
To investigate the association of tag-SNPs and haplotype structures of the CIDEA gene with obesity in a Han Chinese population. Five single nucleotide polymorphisms (SNPs) (rs1154588/V115F, rs4796955/SNP1, rs8092502/SNP2, rs12962340/SNP3 and rs7230480/SNP4) in the CIDEA gene were genotyped in a case-control study. Genotyping was performed using the sequenom matrix-assisted laser desorption/ionization time-of-flight mass spectrometry iPLEX platform. There were significant differences between the obese and control groups in genotype distributions of V115F (P < 0.001), SNP1 (P = 0.006) and SNP2 (P = 0.005). Carriers of V115F-TT, SNP1-GG and SNP2-CC genotypes had a 2.84-fold (95 % CI 1.73-4.66), 2.19-fold (95 % CI 1.09-4.38) and 4.37-fold (95 % CI 1.21-15.08) increased risk for obesity, respectively. Haplotype analysis showed that GTTC (SNP1/SNP2/V115F/SNP4) had 1.41-fold (95 % CI 1.02-1.95) increased risk for obesity; whereas, haplotype TTGC had 0.48-fold (95 % CI 0.24-0.96) decreased risk for obesity. Using the multifactor dimensionality reduction method, the best model including SNP1, SNP2, V115F and SNP4 polymorphisms was identified with a maximum testing accuracy to 59.32 % and a perfect cross-validation consistency of 10/10 (P = 0.011). Logistic analysis indicated that there was a significant interaction between SNP1 and V115F associated with obesity. Subjects having both genotypes of SNP1/GG and V115F/TT were more susceptible to obesity in the Han Chinese population (OR 2.66, 95 %: 1.22-5.80). Genotypes of V115F/TT, SNP1/GG and SNP2/CC and haplotype GTTC of CIDEA gene were identified as risk factors for obesity in the Han Chinese population. The interaction between SNP1 and V115F could play a joint role in the development of obesity.
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Affiliation(s)
- Jingjing Wu
- Department of Epidemiology and Biostatistics, School of Public Health, Capital Medical University, Beijing, 100069, People's Republic of China
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Krahmer N, Farese RV, Walther TC. Balancing the fat: lipid droplets and human disease. EMBO Mol Med 2013; 5:973-83. [PMID: 23740690 PMCID: PMC3721468 DOI: 10.1002/emmm.201100671] [Citation(s) in RCA: 309] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 04/30/2013] [Accepted: 05/02/2013] [Indexed: 01/04/2023] Open
Abstract
Lipid droplets (LDs) are dynamic, cytosolic lipid-storage organelles found in nearly all cell types. Too many or too few LDs during excess or deficient fat storage lead to many different human diseases. Recent insights into LD biology and LD protein functions shed new light on mechanisms underlying those metabolic pathologies. These findings will likely provide opportunities for treatment of diseases associated with too much or too little fat.
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Affiliation(s)
- Natalie Krahmer
- Department of Cell Biology, Yale School of MedicineNew Haven, CT, USA
| | - Robert V Farese
- Gladstone Institutes, Departments of Medicine and Biochemistry & Biophysics, University of CaliforniaSan Francisco, CA, USA
| | - Tobias C Walther
- Department of Cell Biology, Yale School of MedicineNew Haven, CT, USA
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Dahlman I, Arner P. Genetics of adipose tissue biology. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 94:39-74. [PMID: 21036322 DOI: 10.1016/b978-0-12-375003-7.00003-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Adipose tissue morphology and release of free fatty acids, as well as peptide hormones, are believed to contribute to obesity and related metabolic disorders. These adipose tissue phenotypes are influenced by adiposity, but there is also a strong hereditary impact. Polymorphisms in numerous adipose-expressed genes have been evaluated for association with adipocyte and clinical phenotypes. In our opinion, some results are convincing. Thus ADRB2 and GPR74 genes are associated with adipocyte lipolysis, GPR74 also with BMI; PPARG and SREBP1, which promote adipogenesis and lipid storage, are associated with T2D and possible adiposity; ADIPOQ and ARL15 are associated with circulating levels of adiponectin, ARL15 also with coronary heart disease. We anticipate that the use of complementary approaches such as expression profiling and RNAi screening, and studies of additional levels of gene regulation, that is, miRNA and epigenetics, will be important to unravel the genetics of adipose tissue function.
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Ito M, Nagasawa M, Omae N, Ide T, Akasaka Y, Murakami K. Differential regulation of CIDEA and CIDEC expression by insulin via Akt1/2- and JNK2-dependent pathways in human adipocytes. J Lipid Res 2011; 52:1450-60. [PMID: 21636835 DOI: 10.1194/jlr.m012427] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Both insulin and the cell death-inducing DNA fragmentation factor-α-like effector (CIDE) family play important roles in apoptosis and lipid droplet formation. Previously, we reported that CIDEA and CIDEC are differentially regulated by insulin and contribute separately to insulin-induced anti-apoptosis and lipid droplet formation in human adipocytes. However, the upstream signals of CIDE proteins remain unclear. Here, we investigated the signaling molecules involved in insulin regulation of CIDEA and CIDEC expression. The phosphatidylinositol 3-kinase (PI3K) inhibitors wortmannin and PI-103 blocked both insulin-induced downregulation of CIDEA and upregulation of CIDEC. The Akt inhibitor API-2 and the c-Jun N-terminal kinase (JNK) inhibitor SP600125 selectively inhibited insulin regulation of CIDEA and CIDEC expression, respectively, whereas the MAPK/ERK kinase inhibitor U0126 and the p38 inhibitor SB203580 did not. Small interfering RNA-mediated depletion of Akt1/2 prevented insulin-induced downregulation of CIDEA and inhibition of apoptosis. Depletion of JNK2, but not JNK1, inhibited insulin-induced upregulation of CIDEC and lipid droplet enlargement. Furthermore, insulin increased both Akt and JNK phosphorylation, which was abrogated by the PI3K inhibitors. These results suggest that insulin regulates CIDEA and CIDEC expression via PI3K, and it regulates expression of each protein via Akt1/2- and JNK2-dependent pathways, respectively, in human adipocytes.
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Affiliation(s)
- Minoru Ito
- Discovery Research Laboratories, Kyorin Pharmaceutical Co. Ltd., Tochigi 329-0114, Japan
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15
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Greenberg AS, Coleman RA, Kraemer FB, McManaman JL, Obin MS, Puri V, Yan QW, Miyoshi H, Mashek DG. The role of lipid droplets in metabolic disease in rodents and humans. J Clin Invest 2011; 121:2102-10. [PMID: 21633178 DOI: 10.1172/jci46069] [Citation(s) in RCA: 470] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lipid droplets (LDs) are intracellular organelles that store neutral lipids within cells. Over the last two decades there has been a dramatic growth in our understanding of LD biology and, in parallel, our understanding of the role of LDs in health and disease. In its simplest form, the LD regulates the storage and hydrolysis of neutral lipids, including triacylglycerol and/or cholesterol esters. It is becoming increasingly evident that alterations in the regulation of LD physiology and metabolism influence the risk of developing metabolic diseases such as diabetes. In this review we provide an update on the role of LD-associated proteins and LDs in metabolic disease.
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Affiliation(s)
- Andrew S Greenberg
- Obesity and Metabolism Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts 02111, USA.
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Zhang L, Dai Y, Bian L, Wang W, Wang W, Muramatsu M, Hua Q. Association of the cell death-inducing DNA fragmentation factor alpha-like effector A (CIDEA) gene V115F (G/T) polymorphism with phenotypes of metabolic syndrome in a Chinese population. Diabetes Res Clin Pract 2011; 91:233-8. [PMID: 21106268 DOI: 10.1016/j.diabres.2010.10.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 10/09/2010] [Accepted: 10/26/2010] [Indexed: 01/18/2023]
Abstract
AIMS The CIDEA gene is involved in energy metabolism and a non-synonymous single nucleotide polymorphism (SNP), V115F (G/T), is a risk factor for obesity in Swedish subjects and metabolic syndrome (MetS) in Japanese subjects. However, the risk allele was a G in Swedish subjects and a T in Japanese subjects. The present study investigated the association between this SNP and MetS in a Chinese population. METHODS Three hundred and fifty-one subjects evaluated at the Cardiac Clinic in Xuanwu Hospital for MetS risks were recruited. Anthropometric measurements, blood pressure, fasting blood glucose, and blood lipid levels were determined in addition to the polymorphism. RESULTS The proportion of subjects with MetS was significantly higher based on genotype, in the order: GG<GT<TT (p=0.003). In multiple logistic regression analysis, the odds ratios for MetS in the GT and TT genotypes, compared to the referent GG genotype, were 2.26 (p=0.003) and 2.89 (p=0.002), respectively. Similar trends were observed for the related phenotypes of central obesity (GT: OR=2.20, p=0.004; TT: OR=3.31, p=0.002) and dyslipidemia (GT: OR=1.73, p=0.047; TT: OR=2.10, p=0.03). CONCLUSIONS The T allele of the CIDEA V115F SNP is a risk factor for MetS and its related phenotypes in a Chinese population.
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Affiliation(s)
- Ling Zhang
- Department of Epidemiology and Biostatistics, School of Public Health and Family Medicine, Capital Medical University, No. 129 Mail Box, No. 10 Xitoutiao, Youanmenwai, Beijing 100069, PR China
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Miyaki K, Oo T, Song Y, Lwin H, Tomita Y, Hoshino H, Suzuki N, Muramatsu M. Association of a cyclin-dependent kinase 5 regulatory subunit-associated protein 1-like 1 (CDKAL1) polymorphism with elevated hemoglobin A₁(c) levels and the prevalence of metabolic syndrome in Japanese men: interaction with dietary energy intake. Am J Epidemiol 2010; 172:985-91. [PMID: 20847106 DOI: 10.1093/aje/kwq281] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Genome-wide association studies have identified the cyclin-dependent kinase 5 regulatory subunit-associated protein 1-like 1 (CDKAL1) gene as a novel risk factor for type 2 diabetes mellitus. Application of this genetic marker for prevention of type 2 diabetes and metabolic syndrome (MetS) in healthy populations has not yet been evaluated. The authors examined the effects of a CDKAL1 polymorphism (rs9465871) on metabolic phenotype and of gene-lifestyle (CDKAL1-energy intake) interaction on MetS in a cohort of apparently healthy Japanese men examined in 2003. The CC genotype of the CDKAL1 variant was associated with elevated glycosylated hemoglobin A₁(c) (HbA1c) levels. The prevalence of MetS was 25.6% for CC and 16.3% for TT + CT (odds ratio = 2.18, 95% confidence interval: 1.06, 4.48; P = 0.035). When dietary energy intake was accounted for, the variant's effect on HbA1c was observed in the highest energy-intake group (mean: CC, 5.6% (standard deviation, 1.7); TT + CT, 5.0% (standard deviation, 0.5); P = 0.025). In addition, the positive association between HbA1c and energy intake was stronger in subjects with the CC genotype than in subjects with TT + CT. These results suggest that the interaction between the CDKAL1 polymorphism and dietary energy intake influences the dysglycemic phenotype leading to MetS, possibly through impaired insulin secretion. The CDKAL1 polymorphism may be a marker for MetS in the Japanese population.
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Affiliation(s)
- Koichi Miyaki
- Department of Neurology, Keio University, Tokyo, Japan
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Yonezawa T, Kurata R, Kimura M, Inoko H. Which CIDE are you on? Apoptosis and energy metabolism. MOLECULAR BIOSYSTEMS 2010; 7:91-100. [PMID: 20967381 DOI: 10.1039/c0mb00099j] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Around 1998, cell death-inducing DNA fragmentation factor-alpha (DFFA)-like effector (CIDE) proteins including CIDEA, CIDEB and CIDEC/fat specific protein 27 (Fsp27) were first identified by their sequence homology with the N-terminal domain of the DNA fragmentation factor (DFF). Indeed, in vitro analysis revealed that all three CIDE proteins are involved in apoptosis. However, recent gene-targeting studies have provided novel insights into the physiological function of CIDE proteins. Mice deficient in each CIDE protein exhibit lean phenotypes, a reduction of lipid droplet size in white adipose tissue and increased metabolic rate. Thus, all CIDE proteins play an important role in energy metabolism and lipid droplet formation. More recently, a glycoproteomics approach has shown that post-translational regulation of CIDE proteins via glycosylation modulates transforming growth factor (TGF)-beta 1-dependent apoptosis. Another recent study using mouse embryonic fibroblasts derived from CIDEA-deficient mice revealed that 5'AMP-activated protein kinase (AMPK) activity is regulated by CIDEA-mediated ubiquitin-dependent proteasomal degradation via a protein interaction with the AMPK beta subunit. Even after a decade of study, the physiological roles of CIDE proteins have still not been completely elucidated. This review aims to shed light on the novel functions of CIDE proteins and their physiological roles.
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Affiliation(s)
- Tomo Yonezawa
- Division of Basic Medical Science and Molecular Medicine, School of Medicine, Tokai University, Bohseidai, Ishehara, Kanagawa 259-1193, Japan.
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Identification and Characterization of a Novel Mouse Cidea N-terminal Truncated Isoform*. PROG BIOCHEM BIOPHYS 2010. [DOI: 10.3724/sp.j.1206.2010.00159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ito M, Nagasawa M, Hara T, Ide T, Murakami K. Differential roles of CIDEA and CIDEC in insulin-induced anti-apoptosis and lipid droplet formation in human adipocytes. J Lipid Res 2010; 51:1676-84. [PMID: 20154362 DOI: 10.1194/jlr.m002147] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Both insulin and the cell death-inducing DNA fragmentation factor-alpha-like effector (CIDE) family play important roles in apoptosis and lipid droplet formation. However, regulation of the CIDE family by insulin and the contribution of the CIDE family to insulin actions remain unclear. Here, we investigated whether insulin regulates expression of the CIDE family and which subtypes contribute to insulin-induced anti-apoptosis and lipid droplet formation in human adipocytes. Insulin decreased CIDEA and increased CIDEC but not CIDEB mRNA expression. Starvation-induced apoptosis in adipocytes was significantly inhibited when insulin decreased the CIDEA mRNA level. Small interfering RNA-mediated depletion of CIDEA inhibited starvation-induced apoptosis similarly to insulin and restored insulin deprivation-reduced adipocyte number, whereas CIDEC depletion did not. Lipid droplet size of adipocytes was increased when insulin increased the CIDEC mRNA level. In contrast, insulin-induced enlargement of lipid droplets was markedly abrogated by depletion of CIDEC but not CIDEA. Furthermore, depletion of CIDEC, but not CIDEA, significantly increased glycerol release from adipocytes. These results suggest that CIDEA and CIDEC are novel genes regulated by insulin in human adipocytes and may play key roles in the effects of insulin, such as anti-apoptosis and lipid droplet formation.
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Affiliation(s)
- Minoru Ito
- Discovery Research Laboratories, Kyorin Pharmaceutical Co. Ltd., 2399-1, Nogi, Nogi-machi, Shimotsuga-gun, Tochigi 329-0114, Japan
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Svensson PA, Gummesson A, Carlsson LMS, Sjöholm K. Changes in human adipose tissue gene expression during diet-induced weight loss. JOURNAL OF NUTRIGENETICS AND NUTRIGENOMICS 2010; 3:239-50. [PMID: 21474955 DOI: 10.1159/000324360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Per-Arne Svensson
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Department of Molecular and Clinical Medicine, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
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Abstract
PURPOSE OF REVIEW The cell death-inducing DFF45-like effector (CIDE) family proteins, comprising three members, Cidea, Cideb, and Fsp27 (Cidec), have emerged as important regulators for various aspects of metabolism. This review summarizes our current understanding about the physiological roles of CIDE proteins, their transcriptional regulations, and their underlying mechanism in controlling the development of metabolic disorders. RECENT FINDINGS Animals with deficiency in Cidea, Cideb, and Fsp27 all display lean phenotypes with higher energy expenditure and are resistant to diet-induced obesity and insulin resistance. CIDE proteins, localized to lipid droplets and endoplasmic reticulum, control lipid metabolism in adipocytes and hepatocytes through regulating AMP-activated protein kinase stability and influencing lipogenesis or lipid droplet formation. The expression of CIDE proteins is controlled at both transcriptional and posttranslational levels and positively correlates with the development of obesity, liver steatosis, and insulin sensitivity in both rodents and humans. SUMMARY CIDE proteins are important regulators of energy homeostasis and are closely linked to the development of metabolic disorders including obesity, diabetes, and liver steatosis. They may serve as potential molecular targets for the screening of therapeutic drugs for these diseases.
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Affiliation(s)
- Jingyi Gong
- Protein Science Laboratory of Ministry of Education, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, China
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Abstract
Fat-specific protein of 27 kDa (FSP27) is a highly expressed adipocyte protein that promotes triglyceride accumulation within lipid droplets. In this issue of the JCI, Nishino et al. show that FSP27 also helps to maintain the characteristically large unilocular lipid droplet structure within each white adipocyte (see the related article beginning on page 2808). Fragmentation of lipid droplets in white adipocytes from FSP27-KO mice caused both increased lipolysis and upregulation of genes enhancing mitochondrial oxidative metabolism. This increased energy expenditure in turn protected the mice from diet-induced obesity and insulin resistance. These new results highlight powerful mechanisms that tightly coordinate rates of triglyceride storage in lipid droplets with mitochondrial fatty acid oxidation in white adipocytes.
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Affiliation(s)
- Vishwajeet Puri
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
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