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Korenfeld N, Gorbonos T, Romero Florian MC, Rotaro D, Goldberg D, Radushkevitz-Frishman T, Charni-Natan M, Bar-Shimon M, Cummins CL, Goldstein I. LXR-dependent enhancer activation regulates the temporal organization of the liver's response to refeeding leading to lipogenic gene overshoot. PLoS Biol 2024; 22:e3002735. [PMID: 39241209 PMCID: PMC11379474 DOI: 10.1371/journal.pbio.3002735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 07/04/2024] [Indexed: 09/08/2024] Open
Abstract
Transitions between the fed and fasted state are common in mammals. The liver orchestrates adaptive responses to feeding/fasting by transcriptionally regulating metabolic pathways of energy usage and storage. Transcriptional and enhancer dynamics following cessation of fasting (refeeding) have not been explored. We examined the transcriptional and chromatin events occurring upon refeeding in mice, including kinetic behavior and molecular drivers. We found that the refeeding response is temporally organized with the early response focused on ramping up protein translation while the later stages of refeeding drive a bifurcated lipid synthesis program. While both the cholesterol biosynthesis and lipogenesis pathways were inhibited during fasting, most cholesterol biosynthesis genes returned to their basal levels upon refeeding while most lipogenesis genes markedly overshoot above pre-fasting levels. Gene knockout, enhancer dynamics, and ChIP-seq analyses revealed that lipogenic gene overshoot is dictated by LXRα. These findings from unbiased analyses unravel the mechanism behind the long-known phenomenon of refeeding fat overshoot.
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Affiliation(s)
- Noga Korenfeld
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Tali Gorbonos
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Maria C Romero Florian
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Dan Rotaro
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Dana Goldberg
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Talia Radushkevitz-Frishman
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Meital Charni-Natan
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Meirav Bar-Shimon
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Carolyn L Cummins
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada
| | - Ido Goldstein
- Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
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Mao Z, Mu J, Gao Z, Huang S, Chen L. Biological Functions and Potential Therapeutic Significance of O-GlcNAcylation in Hepatic Cellular Stress and Liver Diseases. Cells 2024; 13:805. [PMID: 38786029 PMCID: PMC11119800 DOI: 10.3390/cells13100805] [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: 04/16/2024] [Revised: 05/07/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
O-linked-β-D-N-acetylglucosamine (O-GlcNAc) glycosylation (O-GlcNAcylation), which is dynamically regulated by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), is a post-translational modification involved in multiple cellular processes. O-GlcNAcylation of proteins can regulate their biological functions via crosstalk with other post-translational modifications, such as phosphorylation, ubiquitination, acetylation, and methylation. Liver diseases are a major cause of death worldwide; yet, key pathological features of the disease, such as inflammation, fibrosis, steatosis, and tumorigenesis, are not fully understood. The dysregulation of O-GlcNAcylation has been shown to be involved in some severe hepatic cellular stress, viral hepatitis, liver fibrosis, nonalcoholic fatty acid liver disease (NAFLD), malignant progression, and drug resistance of hepatocellular carcinoma (HCC) through multiple molecular signaling pathways. Here, we summarize the emerging link between O-GlcNAcylation and hepatic pathological processes and provide information about the development of therapeutic strategies for liver diseases.
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Affiliation(s)
- Zun Mao
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China; (Z.M.); (Z.G.)
| | - Junpeng Mu
- Department of Clinical Medicine, Xuzhou Medical University, Xuzhou 221004, China;
| | - Zhixiang Gao
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China; (Z.M.); (Z.G.)
| | - Shile Huang
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130-3932, USA
- Department of Hematology and Oncology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130-3932, USA
- Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, LA 71130-3932, USA
| | - Long Chen
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China; (Z.M.); (Z.G.)
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3
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Hu YJ, Zhang X, Lv HM, Liu Y, Li SZ. Protein O-GlcNAcylation: The sweet hub in liver metabolic flexibility from a (patho)physiological perspective. Liver Int 2024; 44:293-315. [PMID: 38110988 DOI: 10.1111/liv.15812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/18/2023] [Accepted: 11/22/2023] [Indexed: 12/20/2023]
Abstract
O-GlcNAcylation is a dynamic, reversible and atypical O-glycosylation that regulates various cellular physiological processes via conformation, stabilisation, localisation, chaperone interaction or activity of target proteins. The O-GlcNAcylation cycle is precisely controlled by collaboration between O-GlcNAc transferase and O-GlcNAcase. Uridine-diphosphate-N-acetylglucosamine, the sole donor of O-GlcNAcylation produced by the hexosamine biosynthesis pathway, is controlled by the input of glucose, glutamine, acetyl coenzyme A and uridine triphosphate, making it a sensor of the fluctuation of molecules, making O-GlcNAcylation a pivotal nutrient sensor for the metabolism of carbohydrates, amino acids, lipids and nucleotides. O-GlcNAcylation, particularly prevalent in liver, is the core hub for controlling systemic glucose homeostasis due to its nutritional sensitivity and precise spatiotemporal regulation of insulin signal transduction. The pathology of various liver diseases has highlighted hepatic metabolic disorder and dysfunction, and abnormal O-GlcNAcylation also plays a specific pathological role in these processes. Therefore, this review describes the unique features of O-GlcNAcylation and its dynamic homeostasis maintenance. Additionally, it explains the underlying nutritional sensitivity of O-GlcNAcylation and discusses its mechanism of spatiotemporal modulation of insulin signal transduction and liver metabolic homeostasis during the fasting and feeding cycle. This review emphasises the pathophysiological implications of O-GlcNAcylation in nonalcoholic fatty liver disease, nonalcoholic steatohepatitis and hepatic fibrosis, and focuses on the adverse effects of hyper O-GlcNAcylation on liver cancer progression and metabolic reprogramming.
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Affiliation(s)
- Ya-Jie Hu
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Xu Zhang
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Hong-Ming Lv
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Yang Liu
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Shi-Ze Li
- Key Laboratory of Bovine Disease Control in Northeast China of Ministry of Agriculture and Rural affairs of the People's Republic of China, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
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4
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Nakamoto A, Ohashi N, Sugawara L, Morino K, Ida S, Perry RJ, Sakuma I, Yanagimachi T, Fujita Y, Ugi S, Kume S, Shulman GI, Maegawa H. O-linked N-acetylglucosamine modification is essential for physiological adipose expansion induced by high-fat feeding. Am J Physiol Endocrinol Metab 2023; 325:E46-E61. [PMID: 37224467 PMCID: PMC10292976 DOI: 10.1152/ajpendo.00263.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 05/01/2023] [Accepted: 05/18/2023] [Indexed: 05/26/2023]
Abstract
Adipose tissues accumulate excess energy as fat and heavily influence metabolic homeostasis. O-linked N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation), which involves the addition of N-acetylglucosamine to proteins by O-GlcNAc transferase (Ogt), modulates multiple cellular processes. However, little is known about the role of O-GlcNAcylation in adipose tissues during body weight gain due to overnutrition. Here, we report on O-GlcNAcylation in mice with high-fat diet (HFD)-induced obesity. Mice with knockout of Ogt in adipose tissue achieved using adiponectin promoter-driven Cre recombinase (Ogt-FKO) gained less body weight than control mice under HFD. Surprisingly, Ogt-FKO mice exhibited glucose intolerance and insulin resistance, despite their reduced body weight gain, as well as decreased expression of de novo lipogenesis genes and increased expression of inflammatory genes, resulting in fibrosis at 24 weeks of age. Primary cultured adipocytes derived from Ogt-FKO mice showed decreased lipid accumulation. Both primary cultured adipocytes and 3T3-L1 adipocytes treated with OGT inhibitor showed increased secretion of free fatty acids. Medium derived from these adipocytes stimulated inflammatory genes in RAW 264.7 macrophages, suggesting that cell-to-cell communication via free fatty acids might be a cause of adipose inflammation in Ogt-FKO mice. In conclusion, O-GlcNAcylation is important for healthy adipose expansion in mice. Glucose flux into adipose tissues may be a signal to store excess energy as fat.NEW & NOTEWORTHY We evaluated the role of O-GlcNAcylation in adipose tissue in diet-induced obesity using adipose tissue-specific Ogt knockout mice. We found that O-GlcNAcylation in adipose tissue is essential for healthy fat expansion and that Ogt-FKO mice exhibit severe fibrosis upon long-term overnutrition. O-GlcNAcylation in adipose tissue may regulate de novo lipogenesis and free fatty acid efflux to the degree of overnutrition. We believe that these results provide new insights into adipose tissue physiology and obesity research.
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Affiliation(s)
- Akiko Nakamoto
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Natsuko Ohashi
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
- Department of Stem Cell Biology and Regenerative Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Lucia Sugawara
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Katsutaro Morino
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
- Institutional Research Office, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Shogo Ida
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Rachel J Perry
- Department of Medicine (Endocrinology), Yale University School of Medicine, New Haven, Connecticut, United States
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Ikki Sakuma
- Department of Medicine (Endocrinology), Yale University School of Medicine, New Haven, Connecticut, United States
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | | | - Yukihiro Fujita
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Satoshi Ugi
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Shinji Kume
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
| | - Gerald I Shulman
- Department of Medicine (Endocrinology), Yale University School of Medicine, New Haven, Connecticut, United States
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Hiroshi Maegawa
- Department of Medicine, Shiga University of Medical Science, Otsu, Shiga, Japan
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5
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Uehara K, Santoleri D, Whitlock AEG, Titchenell PM. Insulin Regulation of Hepatic Lipid Homeostasis. Compr Physiol 2023; 13:4785-4809. [PMID: 37358513 PMCID: PMC10760932 DOI: 10.1002/cphy.c220015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
The incidence of obesity, insulin resistance, and type II diabetes (T2DM) continues to rise worldwide. The liver is a central insulin-responsive metabolic organ that governs whole-body metabolic homeostasis. Therefore, defining the mechanisms underlying insulin action in the liver is essential to our understanding of the pathogenesis of insulin resistance. During periods of fasting, the liver catabolizes fatty acids and stored glycogen to meet the metabolic demands of the body. In postprandial conditions, insulin signals to the liver to store excess nutrients into triglycerides, cholesterol, and glycogen. In insulin-resistant states, such as T2DM, hepatic insulin signaling continues to promote lipid synthesis but fails to suppress glucose production, leading to hypertriglyceridemia and hyperglycemia. Insulin resistance is associated with the development of metabolic disorders such as cardiovascular and kidney disease, atherosclerosis, stroke, and cancer. Of note, nonalcoholic fatty liver disease (NAFLD), a spectrum of diseases encompassing fatty liver, inflammation, fibrosis, and cirrhosis, is linked to abnormalities in insulin-mediated lipid metabolism. Therefore, understanding the role of insulin signaling under normal and pathologic states may provide insights into preventative and therapeutic opportunities for the treatment of metabolic diseases. Here, we provide a review of the field of hepatic insulin signaling and lipid regulation, including providing historical context, detailed molecular mechanisms, and address gaps in our understanding of hepatic lipid regulation and the derangements under insulin-resistant conditions. © 2023 American Physiological Society. Compr Physiol 13:4785-4809, 2023.
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Affiliation(s)
- Kahealani Uehara
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Dominic Santoleri
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Anna E. Garcia Whitlock
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Paul M. Titchenell
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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6
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Jeon YG, Kim YY, Lee G, Kim JB. Physiological and pathological roles of lipogenesis. Nat Metab 2023; 5:735-759. [PMID: 37142787 DOI: 10.1038/s42255-023-00786-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 03/15/2023] [Indexed: 05/06/2023]
Abstract
Lipids are essential metabolites, which function as energy sources, structural components and signalling mediators. Most cells are able to convert carbohydrates into fatty acids, which are often converted into neutral lipids for storage in the form of lipid droplets. Accumulating evidence suggests that lipogenesis plays a crucial role not only in metabolic tissues for systemic energy homoeostasis but also in immune and nervous systems for their proliferation, differentiation and even pathophysiological roles. Thus, excessive or insufficient lipogenesis is closely associated with aberrations in lipid homoeostasis, potentially leading to pathological consequences, such as dyslipidaemia, diabetes, fatty liver, autoimmune diseases, neurodegenerative diseases and cancers. For systemic energy homoeostasis, multiple enzymes involved in lipogenesis are tightly controlled by transcriptional and post-translational modifications. In this Review, we discuss recent findings regarding the regulatory mechanisms, physiological roles and pathological importance of lipogenesis in multiple tissues such as adipose tissue and the liver, as well as the immune and nervous systems. Furthermore, we briefly introduce the therapeutic implications of lipogenesis modulation.
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Affiliation(s)
- Yong Geun Jeon
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Ye Young Kim
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Gung Lee
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Jae Bum Kim
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea.
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7
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Kim H, Park C, Kim TH. Targeting Liver X Receptors for the Treatment of Non-Alcoholic Fatty Liver Disease. Cells 2023; 12:cells12091292. [PMID: 37174692 PMCID: PMC10177243 DOI: 10.3390/cells12091292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 04/29/2023] [Accepted: 04/29/2023] [Indexed: 05/15/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) refers to a range of conditions in which excess lipids accumulate in the liver, possibly leading to serious hepatic manifestations such as steatohepatitis, fibrosis/cirrhosis and cancer. Despite its increasing prevalence and significant impact on liver disease-associated mortality worldwide, no medication has been approved for the treatment of NAFLD yet. Liver X receptors α/β (LXRα and LXRβ) are lipid-activated nuclear receptors that serve as master regulators of lipid homeostasis and play pivotal roles in controlling various metabolic processes, including lipid metabolism, inflammation and immune response. Of note, NAFLD progression is characterized by increased accumulation of triglycerides and cholesterol, hepatic de novo lipogenesis, mitochondrial dysfunction and augmented inflammation, all of which are highly attributed to dysregulated LXR signaling. Thus, targeting LXRs may provide promising strategies for the treatment of NAFLD. However, emerging evidence has revealed that modulating the activity of LXRs has various metabolic consequences, as the main functions of LXRs can distinctively vary in a cell type-dependent manner. Therefore, understanding how LXRs in the liver integrate various signaling pathways and regulate metabolic homeostasis from a cellular perspective using recent advances in research may provide new insights into therapeutic strategies for NAFLD and associated metabolic diseases.
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Affiliation(s)
- Hyejin Kim
- College of Pharmacy, Sookmyung Women's University, Seoul 04310, Republic of Korea
| | - Chaewon Park
- College of Pharmacy, Sookmyung Women's University, Seoul 04310, Republic of Korea
| | - Tae Hyun Kim
- College of Pharmacy, Sookmyung Women's University, Seoul 04310, Republic of Korea
- Drug Information Research Institute, Sookmyung Women's University, Seoul 04310, Republic of Korea
- Muscle Physiome Research Center, Sookmyung Women's University, Seoul 04310, Republic of Korea
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8
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Favalier N, Roy J, Dias K, Maunas P, Turonnet N, Conde-Sieira M, Panserat S, Soengas JL, Marandel L. Sex dimorphism of glucosensing parameters and appetite-regulating peptides in the hypothalamus of rainbow trout broodstocks. Comp Biochem Physiol A Mol Integr Physiol 2023; 281:111436. [PMID: 37085140 DOI: 10.1016/j.cbpa.2023.111436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 04/03/2023] [Accepted: 04/17/2023] [Indexed: 04/23/2023]
Abstract
Rainbow trout (Oncorhynchus mykiss) is traditionally considered as a poor user of digestible carbohydrates harbouring persistent postprandial hyperglycaemia and decreased growth performances when fed a diet containing more than 20% of digestible carbohydrates. While this glucose-intolerant phenotype is well-described in juveniles, evidence points to a particular regulation of glucose metabolism in rainbow trout broodstrocks. By detecting changes in glucose levels and triggering a specific metabolic response, the hypothalamus plays a key role in the regulation of peripheral glucose metabolism. Therefore, our objective was to assess, for the first time in fish, the short-term consequences in hypothalamus, the glucose sensing and feed intake regulation of feeding mature female and male, and neomale rainbow trout with a diet containing either no or a 33% carbohydrate. The hypothalamic glucosensing capacity was assessed through mRNA levels of glucosensing related-genes and feed intake regulation through appetite-regulating peptides. Our data indicate that a brief period of carbohydrate intake (5 meals at 8 °C) did not induce specific changes in glucosensing capacity and appetite-regulating peptides in the hypothalamus of rainbow trout broodstock. Our results did however demonstrate, for the first time in fish, the existence of sex dimorphism of glucosensing-related genes and appetite-regulating peptides.
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Affiliation(s)
- Nathan Favalier
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Jérôme Roy
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Karine Dias
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Patrick Maunas
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Nicolas Turonnet
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Stephane Panserat
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - José Luis Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Lucie Marandel
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France.
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9
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Emerging Role of Protein O-GlcNAcylation in Liver Metabolism: Implications for Diabetes and NAFLD. Int J Mol Sci 2023; 24:ijms24032142. [PMID: 36768465 PMCID: PMC9916810 DOI: 10.3390/ijms24032142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/16/2023] [Accepted: 01/18/2023] [Indexed: 01/24/2023] Open
Abstract
O-linked b-N-acetyl-glucosaminylation (O-GlcNAcylation) is one of the most common post-translational modifications of proteins, and is established by modifying the serine or threonine residues of nuclear, cytoplasmic, and mitochondrial proteins. O-GlcNAc signaling is considered a critical nutrient sensor, and affects numerous proteins involved in cellular metabolic processes. O-GlcNAcylation modulates protein functions in different patterns, including protein stabilization, enzymatic activity, transcriptional activity, and protein interactions. Disrupted O-GlcNAcylation is associated with an abnormal metabolic state, and may result in metabolic disorders. As the liver is the center of nutrient metabolism, this review provides a brief description of the features of the O-GlcNAc signaling pathway, and summarizes the regulatory functions and underlying molecular mechanisms of O-GlcNAcylation in liver metabolism. Finally, this review highlights the role of O-GlcNAcylation in liver-associated diseases, such as diabetes and nonalcoholic fatty liver disease (NAFLD). We hope this review not only benefits the understanding of O-GlcNAc biology, but also provides new insights for treatments against liver-associated metabolic disorders.
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10
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Jo R, Shibata H, Kurihara I, Yokota K, Kobayashi S, Murai-Takeda A, Mitsuishi Y, Hayashi T, Nakamura T, Itoh H. Mechanisms of mineralocorticoid receptor-associated hypertension in diabetes mellitus: the role of O-GlcNAc modification. Hypertens Res 2023; 46:19-31. [PMID: 36229526 DOI: 10.1038/s41440-022-01036-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 09/04/2022] [Accepted: 09/05/2022] [Indexed: 02/03/2023]
Abstract
This study investigated the mechanism underlying the beneficial effects of mineralocorticoid receptor (MR) antagonists in patients with resistant hypertension and diabetic nephropathy by examining post-translational modification of the MR by O-linked-N-acetylglucosamine (O-GlcNAc), which is strongly associated with type 2 diabetes. Coimmunoprecipitation assays in HEK293T cells showed that MR is a target of O-GlcNAc modification (O-GlcNAcylation). The expression levels and transcriptional activities of the receptor increased in parallel with its O-GlcNAcylation under high-glucose conditions. Liquid chromatography-tandem mass spectrometry revealed O-GlcNAcylation of the MR at amino acids 295-307. Point mutations in those residues decreased O-GlcNAcylation, and both the protein levels and transcriptional activities of MR. In db/db mouse kidneys, MR protein levels increased in parallel with overall O-GlcNAc levels of the tissue, accompanied by increased SGK1 mRNA levels. The administration of 6-diazo-5-oxo-L-norleucin, an inhibitor of O-GlcNAcylation, reduced tissue O-GlcNAc levels and MR protein levels in db/db mice. Thus, our study showed that O-GlcNAcylation of the MR directly increases protein levels and transcriptional activities of the receptor under high-glucose conditions in vitro and in vivo. These findings provide a novel mechanism of MR as a target for prevention of complications associated with diabetes mellitus.
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Affiliation(s)
- Rie Jo
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.,Keiyu Hospital, Kanagawa, Japan
| | - Hirotaka Shibata
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan. .,Department of Endocrinology, Metabolism, Rheumatology and Nephrology, Faculty of Medicine, Oita University, Oita, Japan.
| | - Isao Kurihara
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.,Department of Medical Education, National Defense Medical College, Saitama, Japan
| | - Kenichi Yokota
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.,Division of Metabolism and Endocrinology, Department of Internal Medicine, St. Marianna University School of Medicine, Kanagawa, Japan
| | - Sakiko Kobayashi
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan
| | - Ayano Murai-Takeda
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.,Health Center, Keio University, Kanagawa, Japan
| | - Yuko Mitsuishi
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.,Center of Preventive Medicine, Keio University Hospital, Tokyo, Japan
| | - Takeshi Hayashi
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan.,Hayashi Clinic, Tokyo, Japan
| | - Toshifumi Nakamura
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan
| | - Hiroshi Itoh
- Division of Endocrinology, Metabolism and Nephrology, Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan
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11
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Zhou Y, Li Z, Xu M, Zhang D, Ling J, Yu P, Shen Y. O-GlycNacylation Remission Retards the Progression of Non-Alcoholic Fatty Liver Disease. Cells 2022; 11:cells11223637. [PMID: 36429065 PMCID: PMC9688300 DOI: 10.3390/cells11223637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/04/2022] [Accepted: 11/10/2022] [Indexed: 11/18/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a metabolic disease spectrum associated with insulin resistance (IR), from non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma (HCC). O-GlcNAcylation is a posttranslational modification, regulated by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Abnormal O-GlcNAcylation plays a key role in IR, fat deposition, inflammatory injury, fibrosis, and tumorigenesis. However, the specific mechanisms and clinical treatments of O-GlcNAcylation and NAFLD are yet to be elucidated. The modification contributes to understanding the pathogenesis and development of NAFLD, thus clarifying the protective effect of O-GlcNAcylation inhibition on liver injury. In this review, the crucial role of O-GlcNAcylation in NAFLD (from NAFL to HCC) is discussed, and the effect of therapeutics on O-GlcNAcylation and its potential mechanisms on NAFLD have been highlighted. These inferences present novel insights into the pathogenesis and treatments of NAFLD.
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Affiliation(s)
- Yicheng Zhou
- Department of Endocrinology and Metabolism, the Second Affiliated Hospital of Nanchang University, Branch of Nationlal Clinical Research Center for Metabolic Diseases, Institute for the Study of Endocrinology and Metabolism in Jiangxi Province, Nanchang 330006, China
| | - Zhangwang Li
- The Second Clinical Medical College of Nanchang University, Nanchang 330031, China
| | - Minxuan Xu
- Department of Endocrinology and Metabolism, the Second Affiliated Hospital of Nanchang University, Branch of Nationlal Clinical Research Center for Metabolic Diseases, Institute for the Study of Endocrinology and Metabolism in Jiangxi Province, Nanchang 330006, China
| | - Deju Zhang
- Food and Nutritional Sciences, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Jitao Ling
- Department of Endocrinology and Metabolism, the Second Affiliated Hospital of Nanchang University, Branch of Nationlal Clinical Research Center for Metabolic Diseases, Institute for the Study of Endocrinology and Metabolism in Jiangxi Province, Nanchang 330006, China
| | - Peng Yu
- Department of Endocrinology and Metabolism, the Second Affiliated Hospital of Nanchang University, Branch of Nationlal Clinical Research Center for Metabolic Diseases, Institute for the Study of Endocrinology and Metabolism in Jiangxi Province, Nanchang 330006, China
- Correspondence: (P.Y.); (Y.S.)
| | - Yunfeng Shen
- Department of Endocrinology and Metabolism, the Second Affiliated Hospital of Nanchang University, Branch of Nationlal Clinical Research Center for Metabolic Diseases, Institute for the Study of Endocrinology and Metabolism in Jiangxi Province, Nanchang 330006, China
- Correspondence: (P.Y.); (Y.S.)
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12
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Hu A, Zou H, Chen B, Zhong J. Posttranslational modifications in diabetes: Mechanisms and functions. Rev Endocr Metab Disord 2022; 23:1011-1033. [PMID: 35697961 DOI: 10.1007/s11154-022-09740-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/20/2022] [Indexed: 12/15/2022]
Abstract
As one of the most widespread chronic diseases, diabetes and its accompanying complications affect approximately one tenth of individuals worldwide and represent a growing cause of morbidity and mortality. Accumulating evidence has proven that the process of diabetes is complex and interactive, involving various cellular responses and signaling cascades by posttranslational modifications (PTMs). Therefore, understanding the mechanisms and functions of PTMs in regulatory networks has fundamental importance for understanding the prediction, onset, diagnosis, progression, and treatment of diabetes. In this review, we offer a holistic summary and illustration of the crosstalk between PTMs and diabetes, including both types 1 and 2. Meanwhile, we discuss the potential use of PTMs in diabetes treatment and provide a prospective direction for deeply understanding the metabolic diseases.
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Affiliation(s)
- Ang Hu
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China
| | - Haohong Zou
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China
| | - Bin Chen
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China
- The First Affiliated Hospital of Gannan Medical University, Ganzhou, China
| | - Jianing Zhong
- Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases, Ministry of Education, Gannan Medical University, 323 National Road, Ganzhou, 341000, Jiangxi, China.
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13
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Liu Y, Hu Y, Li S. Protein O-GlcNAcylation in Metabolic Modulation of Skeletal Muscle: A Bright but Long Way to Go. Metabolites 2022; 12:888. [PMID: 36295790 PMCID: PMC9610910 DOI: 10.3390/metabo12100888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/09/2022] [Accepted: 09/17/2022] [Indexed: 09/07/2024] Open
Abstract
O-GlcNAcylation is an atypical, dynamic and reversible O-glycosylation that is critical and abundant in metazoan. O-GlcNAcylation coordinates and receives various signaling inputs such as nutrients and stresses, thus spatiotemporally regulating the activity, stability, localization and interaction of target proteins to participate in cellular physiological functions. Our review discusses in depth the involvement of O-GlcNAcylation in the precise regulation of skeletal muscle metabolism, such as glucose homeostasis, insulin sensitivity, tricarboxylic acid cycle and mitochondrial biogenesis. The complex interaction and precise modulation of O-GlcNAcylation in these nutritional pathways of skeletal muscle also provide emerging mechanical information on how nutrients affect health, exercise and disease. Meanwhile, we explored the potential role of O-GlcNAcylation in skeletal muscle pathology and focused on its benefits in maintaining proteostasis under atrophy. In general, these understandings of O-GlcNAcylation are conducive to providing new insights into skeletal muscle (patho) physiology.
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Affiliation(s)
| | | | - Shize Li
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China
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14
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Lockridge A, Hanover JA. A nexus of lipid and O-Glcnac metabolism in physiology and disease. Front Endocrinol (Lausanne) 2022; 13:943576. [PMID: 36111295 PMCID: PMC9468787 DOI: 10.3389/fendo.2022.943576] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Although traditionally considered a glucose metabolism-associated modification, the O-linked β-N-Acetylglucosamine (O-GlcNAc) regulatory system interacts extensively with lipids and is required to maintain lipid homeostasis. The enzymes of O-GlcNAc cycling have molecular properties consistent with those expected of broad-spectrum environmental sensors. By direct protein-protein interactions and catalytic modification, O-GlcNAc cycling enzymes may provide both acute and long-term adaptation to stress and other environmental stimuli such as nutrient availability. Depending on the cell type, hyperlipidemia potentiates or depresses O-GlcNAc levels, sometimes biphasically, through a diversity of unique mechanisms that target UDP-GlcNAc synthesis and the availability, activity and substrate selectivity of the glycosylation enzymes, O-GlcNAc Transferase (OGT) and O-GlcNAcase (OGA). At the same time, OGT activity in multiple tissues has been implicated in the homeostatic regulation of systemic lipid uptake, storage and release. Hyperlipidemic patterns of O-GlcNAcylation in these cells are consistent with both transient physiological adaptation and feedback uninhibited obesogenic and metabolic dysregulation. In this review, we summarize the numerous interconnections between lipid and O-GlcNAc metabolism. These links provide insights into how the O-GlcNAc regulatory system may contribute to lipid-associated diseases including obesity and metabolic syndrome.
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Affiliation(s)
- Amber Lockridge
- Laboratory of Cell and Molecular Biology, National Institute for Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - John A. Hanover
- Laboratory of Cell and Molecular Biology, National Institute for Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
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15
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Sato T, Sassone-Corsi P. Nutrition, metabolism, and epigenetics: pathways of circadian reprogramming. EMBO Rep 2022; 23:e52412. [PMID: 35412705 PMCID: PMC9066069 DOI: 10.15252/embr.202152412] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 10/28/2021] [Accepted: 03/30/2022] [Indexed: 01/07/2023] Open
Abstract
Food intake profoundly affects systemic physiology. A large body of evidence has indicated a link between food intake and circadian rhythms, and ~24-h cycles are deemed essential for adapting internal homeostasis to the external environment. Circadian rhythms are controlled by the biological clock, a molecular system remarkably conserved throughout evolution. The circadian clock controls the cyclic expression of numerous genes, a regulatory program common to all mammalian cells, which may lead to various metabolic and physiological disturbances if hindered. Although the circadian clock regulates multiple metabolic pathways, metabolic states also provide feedback on the molecular clock. Therefore, a remarkable feature is reprogramming by nutritional challenges, such as a high-fat diet, fasting, ketogenic diet, and caloric restriction. In addition, various factors such as energy balance, histone modifications, and nuclear receptor activity are involved in the remodeling of the clock. Herein, we review the interaction of dietary components with the circadian system and illustrate the relationships linking the molecular clock to metabolism and critical roles in the remodeling process.
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Affiliation(s)
- Tomoki Sato
- Department of Biological Chemistry, Center for Epigenetics and Metabolism, School of Medicine, INSERM U1233, University of California, Irvine, CA, USA
| | - Paolo Sassone-Corsi
- Department of Biological Chemistry, Center for Epigenetics and Metabolism, School of Medicine, INSERM U1233, University of California, Irvine, CA, USA
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16
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Zhang H, Li Z, Wang Y, Kong Y. O-GlcNAcylation is a key regulator of multiple cellular metabolic pathways. PeerJ 2021. [DOI: 10.7717/peerj.11443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
O-GlcNAcylation modifies proteins in serine or threonine residues in the nucleus, cytoplasm, and mitochondria. It regulates a variety of cellular biological processes and abnormal O-GlcNAcylation is associated with diabetes, cancer, cardiovascular disease, and neurodegenerative diseases. Recent evidence has suggested that O-GlcNAcylation acts as a nutrient sensor and signal integrator to regulate metabolic signaling, and that dysregulation of its metabolism may be an important indicator of pathogenesis in disease. Here, we review the literature focusing on O-GlcNAcylation regulation in major metabolic processes, such as glucose metabolism, mitochondrial oxidation, lipid metabolism, and amino acid metabolism. We discuss its role in physiological processes, such as cellular nutrient sensing and homeostasis maintenance. O-GlcNAcylation acts as a key regulator in multiple metabolic processes and pathways. Our review will provide a better understanding of how O-GlcNAcylation coordinates metabolism and integrates molecular networks.
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17
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Bravo-Ruiz I, Medina MÁ, Martínez-Poveda B. From Food to Genes: Transcriptional Regulation of Metabolism by Lipids and Carbohydrates. Nutrients 2021; 13:nu13051513. [PMID: 33946267 PMCID: PMC8145205 DOI: 10.3390/nu13051513] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 04/28/2021] [Indexed: 12/31/2022] Open
Abstract
Lipids and carbohydrates regulate gene expression by means of molecules that sense these macronutrients and act as transcription factors. The peroxisome proliferator-activated receptor (PPAR), activated by some fatty acids or their derivatives, and the carbohydrate response element binding protein (ChREBP), activated by glucose-derived metabolites, play a key role in metabolic homeostasis, especially in glucose and lipid metabolism. Furthermore, the action of both factors in obesity, diabetes and fatty liver, as well as the pharmacological development in the treatment of these pathologies are indeed of high relevance. In this review we present an overview of the discovery, mechanism of activation and metabolic functions of these nutrient-dependent transcription factors in different tissues contexts, from the nutritional genomics perspective. The possibility of targeting these factors in pharmacological approaches is also discussed. Lipid and carbohydrate-dependent transcription factors are key players in the complex metabolic homeostasis, but these factors also drive an adaptive response to non-physiological situations, such as overeating. Possibly the decisive role of ChREBP and PPAR in metabolic regulation points to them as ideal therapeutic targets, but their pleiotropic functions in different tissues makes it difficult to "hit the mark".
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Affiliation(s)
- Inés Bravo-Ruiz
- Andalucía Tech, Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain; (I.B.-R.); (M.Á.M.)
| | - Miguel Ángel Medina
- Andalucía Tech, Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain; (I.B.-R.); (M.Á.M.)
- Instituto de Investigación Biomédica de Málaga (IBIMA), E-29071 Málaga, Spain
- CIBER de Enfermedades Raras (CIBERER), E-29071 Málaga, Spain
| | - Beatriz Martínez-Poveda
- Andalucía Tech, Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain; (I.B.-R.); (M.Á.M.)
- Instituto de Investigación Biomédica de Málaga (IBIMA), E-29071 Málaga, Spain
- CIBER de Enfermedades Cardiovasculares (CIBERCV), E-28029 Madrid, Spain
- Correspondence:
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18
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Abstract
Mammals undergo regular cycles of fasting and feeding that engage dynamic transcriptional responses in metabolic tissues. Here we review advances in our understanding of the gene regulatory networks that contribute to hepatic responses to fasting and feeding. The advent of sequencing and -omics techniques have begun to facilitate a holistic understanding of the transcriptional landscape and its plasticity. We highlight transcription factors, their cofactors, and the pathways that they impact. We also discuss physiological factors that impinge on these responses, including circadian rhythms and sex differences. Finally, we review how dietary modifications modulate hepatic gene expression programs.
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Affiliation(s)
- Lara Bideyan
- Department of Pathology and Laboratory Medicine, and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, USA.,Department of Biological Chemistry, and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Rohith Nagari
- Department of Pathology and Laboratory Medicine, and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, USA.,Department of Biological Chemistry, and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Peter Tontonoz
- Department of Pathology and Laboratory Medicine, and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, USA.,Department of Biological Chemistry, and Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, USA
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19
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Russo-Savage L, Schulman IG. Liver X receptors and liver physiology. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166121. [PMID: 33713792 DOI: 10.1016/j.bbadis.2021.166121] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/26/2021] [Accepted: 03/01/2021] [Indexed: 12/29/2022]
Abstract
The liver x receptors LXRα (NR1H3) and LXRβ (NR1H2) are members of the nuclear hormone receptor superfamily of ligand dependent transcription factors that regulate transcription in response to the direct binding of cholesterol derivatives. Studies using genetic knockouts and synthetic ligands have defined the LXRs as important modulators of lipid homeostasis throughout the body. This review focuses on the control of cholesterol and fatty acid metabolism by LXRs in the liver and how modifying LXR activity can influence the pathology of liver diseases.
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Affiliation(s)
- Lillian Russo-Savage
- Department of Pharmacology, University of Virginia, School of Medicine, United States of America
| | - Ira G Schulman
- Department of Pharmacology, University of Virginia, School of Medicine, United States of America.
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20
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Ma J, Wu C, Hart GW. Analytical and Biochemical Perspectives of Protein O-GlcNAcylation. Chem Rev 2021; 121:1513-1581. [DOI: 10.1021/acs.chemrev.0c00884] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Junfeng Ma
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington D.C. 20057, United States
| | - Ci Wu
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington D.C. 20057, United States
| | - Gerald W. Hart
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602, United States
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21
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Effects of dietary carbohydrate sources on lipid metabolism and SUMOylation modification in the liver tissues of yellow catfish. Br J Nutr 2020; 124:1241-1250. [PMID: 32600495 DOI: 10.1017/s0007114520002408] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dysregulation in hepatic lipid synthesis by excess dietary carbohydrate intake is often relevant with the occurrence of fatty liver; therefore, the thorough understanding of the regulation of lipid deposition and metabolism seems crucial to search for potential regulatory targets. In the present study, we examined TAG accumulation, lipid metabolism-related gene expression, the enzyme activities of lipogenesis-related enzymes, the protein levels of transcription factors or genes involving lipogenesis in the livers of yellow catfish fed five dietary carbohydrate sources, such as glucose, maize starch, sucrose, potato starch and dextrin, respectively. Generally speaking, compared with other carbohydrate sources, dietary glucose promoted TAG accumulation, up-regulated lipogenic enzyme activities and gene expressions, and down-regulated mRNA expression of genes involved in lipolysis and small ubiquitin-related modifier (SUMO) modification pathways. Further studies found that sterol regulatory element binding protein 1 (SREBP1), a key transcriptional factor relevant to lipogenic regulation, was modified by SUMO1. Mutational analyses found two important sites for SUMOylation modification (K254R and K264R) in SREBP1. Mutant SREBP lacking lysine 264 up-regulated the transactivation capacity on an SREBP-responsive promoter. Glucose reduced the SUMOylation level of SREBP1 and promoted the protein expression of SREBP1 and its target gene stearoyl-CoA desaturase 1 (SCD1), indicating that SUMOylation of SREBP1 mediated glucose-induced hepatic lipid metabolism. Our study elucidated the molecular mechanism of dietary glucose increasing hepatic lipid deposition and found that the SREBP-dependent transactivation was regulated by SUMO1 modification, which served as a new target for the transcriptional programmes governing lipid metabolism.
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22
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Zhao L, Lei W, Deng C, Wu Z, Sun M, Jin Z, Song Y, Yang Z, Jiang S, Shen M, Yang Y. The roles of liver X receptor α in inflammation and inflammation-associated diseases. J Cell Physiol 2020; 236:4807-4828. [PMID: 33305467 DOI: 10.1002/jcp.30204] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 10/19/2020] [Accepted: 11/24/2020] [Indexed: 12/14/2022]
Abstract
Liver X receptor α (LXRα; also known as NR1H3), an isoform of LXRs, is a member of the nuclear receptor family of transcription factors and plays essential roles in the transcriptional control of cholesterol homeostasis. Previous in-depth phenotypic analyses of mouse models with deficient LXRα have also demonstrated various physiological functions of this receptor within inflammatory responses. LXRα activation exerts a combination of metabolic and anti-inflammatory actions resulting in the modulation and the amelioration of inflammatory disorders. The tight "repercussions" between LXRα and inflammation, as well as cholesterol homeostasis, have suggested that LXRα could be pharmacologically targeted in pathologies such as atherosclerosis, acute lung injury, and Alzheimer's disease. This review gives an overview of the recent advances in understanding the roles of LXRα in inflammation and inflammation-associated diseases, which will help in the design of future experimental researches on the potential of LXRα and advance the investigation of LXRα as pharmacological inflammatory targets.
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Affiliation(s)
- Lin Zhao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Life of Sciences, Northwest University, Xi'an, China.,Department of Cardiovascular Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Wangrui Lei
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Life of Sciences, Northwest University, Xi'an, China
| | - Chao Deng
- Department of Cardiovascular Surgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Zhen Wu
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Life of Sciences, Northwest University, Xi'an, China
| | - Meng Sun
- Department of Cardiology, The First Hospital of Shanxi Medical University, Taiyuan, China
| | - Zhenxiao Jin
- Department of Cardiovascular Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Yanbin Song
- Department of Cardiology, Affiliated Hospital, Yan'an University, China
| | - Zhi Yang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Life of Sciences, Northwest University, Xi'an, China
| | - Shuai Jiang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Life of Sciences, Northwest University, Xi'an, China
| | - Mingzhi Shen
- Hainan Hospital of PLA General Hospital, The Second School of Clinical Medicine, Southern Medical University, Sanya, Hainan, China.,Hainan Branch of National Clinical Reasearch Center of Geriatrics Disease, Sanya, Hainan, China
| | - Yang Yang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education Life of Sciences, Northwest University, Xi'an, China
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23
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Konzman D, Abramowitz LK, Steenackers A, Mukherjee MM, Na HJ, Hanover JA. O-GlcNAc: Regulator of Signaling and Epigenetics Linked to X-linked Intellectual Disability. Front Genet 2020; 11:605263. [PMID: 33329753 PMCID: PMC7719714 DOI: 10.3389/fgene.2020.605263] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/20/2020] [Indexed: 12/13/2022] Open
Abstract
Cellular identity in multicellular organisms is maintained by characteristic transcriptional networks, nutrient consumption, energy production and metabolite utilization. Integrating these cell-specific programs are epigenetic modifiers, whose activity is often dependent on nutrients and their metabolites to function as substrates and co-factors. Emerging data has highlighted the role of the nutrient-sensing enzyme O-GlcNAc transferase (OGT) as an epigenetic modifier essential in coordinating cellular transcriptional programs and metabolic homeostasis. OGT utilizes the end-product of the hexosamine biosynthetic pathway to modify proteins with O-linked β-D-N-acetylglucosamine (O-GlcNAc). The levels of the modification are held in check by the O-GlcNAcase (OGA). Studies from model organisms and human disease underscore the conserved function these two enzymes of O-GlcNAc cycling play in transcriptional regulation, cellular plasticity and mitochondrial reprogramming. Here, we review these findings and present an integrated view of how O-GlcNAc cycling may contribute to cellular memory and transgenerational inheritance of responses to parental stress. We focus on a rare human genetic disorder where mutant forms of OGT are inherited or acquired de novo. Ongoing analysis of this disorder, OGT- X-linked intellectual disability (OGT-XLID), provides a window into how epigenetic factors linked to O-GlcNAc cycling may influence neurodevelopment.
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Affiliation(s)
| | | | | | | | | | - John A. Hanover
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
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24
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Christensen JJ, Ulven SM, Thoresen M, Westerman K, Holven KB, Andersen LF. Associations between dietary patterns and gene expression pattern in peripheral blood mononuclear cells: A cross-sectional study. Nutr Metab Cardiovasc Dis 2020; 30:2111-2122. [PMID: 32807640 DOI: 10.1016/j.numecd.2020.06.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/25/2020] [Accepted: 06/18/2020] [Indexed: 01/12/2023]
Abstract
BACKGROUND AND AIMS Diet may alter gene expression in immune cells involved in atherosclerotic cardiovascular disease susceptibility. However, we still lack a robust understanding of the association between diet and immune cell-related gene expression in humans. Therefore, we examined associations between dietary patterns (DPs) and gene expression profiles in peripheral blood mononuclear cells (PBMCs) in a population of healthy, Norwegian adults (n = 130 women and 105 men). METHODS AND RESULTS We used factor analysis to define a posteriori DPs from food frequency questionnaire-based dietary assessment data. In addition, we derived interpretable features from microarray-based gene expression data (13 967 transcripts) using two algorithms: CIBERSORT for estimation of cell subtype proportions, and weighted gene co-expression network analysis (WGCNA) for cluster discovery. Finally, we associated DPs with either CIBERSORT-predicted PBMC leukocyte distribution or WGCNA gene clusters using linear regression models. We detected three DPs that broadly reflected Western, Vegetarian, and Low carbohydrate diets. CIBERSORT-predicted percentage of monocytes associated negatively with the Vegetarian DP. For women, the Vegetarian DP associated with a large gene cluster consisting of 600 genes mainly involved in regulation of DNA transcription, whereas for men, the Western DP inversely associated with a smaller cluster of 36 genes mainly involved in regulation of metabolic and inflammatory processes. A subsequent protein-protein interaction network analysis suggested that genes within these clusters might physically interact in biological networks. CONCLUSIONS Although the present findings are exploratory, our analysis pipeline serves as a useful framework for studying the association between diet and gene expression.
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Affiliation(s)
- Jacob J Christensen
- Norwegian National Advisory Unit on Familial Hypercholesterolemia, Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Forskningsveien 2B, 0373 Oslo, Norway; Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Sognsvannsveien 9, 0372 Oslo, Norway.
| | - Stine M Ulven
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Sognsvannsveien 9, 0372 Oslo, Norway
| | - Magne Thoresen
- Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Sognsvannsveien 9, 0372 Oslo, Norway
| | - Kenneth Westerman
- Clinical and Translation Epidemiology Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA, USA; Programs in Metabolism and Medical & Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Kirsten B Holven
- Norwegian National Advisory Unit on Familial Hypercholesterolemia, Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Forskningsveien 2B, 0373 Oslo, Norway; Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Sognsvannsveien 9, 0372 Oslo, Norway
| | - Lene F Andersen
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Sognsvannsveien 9, 0372 Oslo, Norway
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Chatham JC, Zhang J, Wende AR. Role of O-Linked N-Acetylglucosamine Protein Modification in Cellular (Patho)Physiology. Physiol Rev 2020; 101:427-493. [PMID: 32730113 DOI: 10.1152/physrev.00043.2019] [Citation(s) in RCA: 154] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In the mid-1980s, the identification of serine and threonine residues on nuclear and cytoplasmic proteins modified by a N-acetylglucosamine moiety (O-GlcNAc) via an O-linkage overturned the widely held assumption that glycosylation only occurred in the endoplasmic reticulum, Golgi apparatus, and secretory pathways. In contrast to traditional glycosylation, the O-GlcNAc modification does not lead to complex, branched glycan structures and is rapidly cycled on and off proteins by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively. Since its discovery, O-GlcNAcylation has been shown to contribute to numerous cellular functions, including signaling, protein localization and stability, transcription, chromatin remodeling, mitochondrial function, and cell survival. Dysregulation in O-GlcNAc cycling has been implicated in the progression of a wide range of diseases, such as diabetes, diabetic complications, cancer, cardiovascular, and neurodegenerative diseases. This review will outline our current understanding of the processes involved in regulating O-GlcNAc turnover, the role of O-GlcNAcylation in regulating cellular physiology, and how dysregulation in O-GlcNAc cycling contributes to pathophysiological processes.
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Affiliation(s)
- John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
| | - Jianhua Zhang
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
| | - Adam R Wende
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
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Voisin M, Gage MC, Becares N, Shrestha E, Fisher EA, Pineda-Torra I, Garabedian MJ. LXRα Phosphorylation in Cardiometabolic Disease: Insight From Mouse Models. Endocrinology 2020; 161:bqaa089. [PMID: 32496563 PMCID: PMC7324054 DOI: 10.1210/endocr/bqaa089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/29/2020] [Indexed: 01/12/2023]
Abstract
Posttranslational modifications, such as phosphorylation, are a powerful means by which the activity and function of nuclear receptors such as LXRα can be altered. However, despite the established importance of nuclear receptors in maintaining metabolic homeostasis, our understanding of how phosphorylation affects metabolic diseases is limited. The physiological consequences of LXRα phosphorylation have, until recently, been studied only in vitro or nonspecifically in animal models by pharmacologically or genetically altering the enzymes enhancing or inhibiting these modifications. Here we review recent reports on the physiological consequences of modifying LXRα phosphorylation at serine 196 (S196) in cardiometabolic disease, including nonalcoholic fatty liver disease, atherosclerosis, and obesity. A unifying theme from these studies is that LXRα S196 phosphorylation rewires the LXR-modulated transcriptome, which in turn alters physiological response to environmental signals, and that this is largely distinct from the LXR-ligand-dependent action.
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Affiliation(s)
- Maud Voisin
- Department of Microbiology, New York University School of Medicine, New York, New York, US
| | - Matthew C Gage
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Natalia Becares
- Centre of Clinical Pharmacology, Division of Medicine, University College of London, London, UK
| | - Elina Shrestha
- Department of Microbiology, New York University School of Medicine, New York, New York, US
| | - Edward A Fisher
- Department of Microbiology, New York University School of Medicine, New York, New York, US
- Department of Medicine, New York University School of Medicine, New York, New York, US
| | - Ines Pineda-Torra
- Centre of Cardiometabolic and Vascular Science, Division of Medicine, University College of London, London, UK
| | - Michael J Garabedian
- Department of Microbiology, New York University School of Medicine, New York, New York, US
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Fan Q, Nørgaard RC, Grytten I, Ness CM, Lucas C, Vekterud K, Soedling H, Matthews J, Lemma RB, Gabrielsen OS, Bindesbøll C, Ulven SM, Nebb HI, Grønning-Wang LM, Sæther T. LXRα Regulates ChREBPα Transactivity in a Target Gene-Specific Manner through an Agonist-Modulated LBD-LID Interaction. Cells 2020; 9:cells9051214. [PMID: 32414201 PMCID: PMC7290792 DOI: 10.3390/cells9051214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/19/2020] [Accepted: 05/07/2020] [Indexed: 01/02/2023] Open
Abstract
The cholesterol-sensing nuclear receptor liver X receptor (LXR) and the glucose-sensing transcription factor carbohydrate responsive element-binding protein (ChREBP) are central players in regulating glucose and lipid metabolism in the liver. More knowledge of their mechanistic interplay is needed to understand their role in pathological conditions like fatty liver disease and insulin resistance. In the current study, LXR and ChREBP co-occupancy was examined by analyzing ChIP-seq datasets from mice livers. LXR and ChREBP interaction was determined by Co-immunoprecipitation (CoIP) and their transactivity was assessed by real-time quantitative polymerase chain reaction (qPCR) of target genes and gene reporter assays. Chromatin binding capacity was determined by ChIP-qPCR assays. Our data show that LXRα and ChREBPα interact physically and show a high co-occupancy at regulatory regions in the mouse genome. LXRα co-activates ChREBPα and regulates ChREBP-specific target genes in vitro and in vivo. This co-activation is dependent on functional recognition elements for ChREBP but not for LXR, indicating that ChREBPα recruits LXRα to chromatin in trans. The two factors interact via their key activation domains; the low glucose inhibitory domain (LID) of ChREBPα and the ligand-binding domain (LBD) of LXRα. While unliganded LXRα co-activates ChREBPα, ligand-bound LXRα surprisingly represses ChREBPα activity on ChREBP-specific target genes. Mechanistically, this is due to a destabilized LXRα:ChREBPα interaction, leading to reduced ChREBP-binding to chromatin and restricted activation of glycolytic and lipogenic target genes. This ligand-driven molecular switch highlights an unappreciated role of LXRα in responding to nutritional cues that was overlooked due to LXR lipogenesis-promoting function.
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Affiliation(s)
- Qiong Fan
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
| | - Rikke Christine Nørgaard
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Ivar Grytten
- Department of Informatics, Faculty of Mathematics and Natural Sciences, University of Oslo, N-0317 Oslo, Norway;
| | - Cecilie Maria Ness
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Christin Lucas
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Kristin Vekterud
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
| | - Helen Soedling
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Jason Matthews
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Roza Berhanu Lemma
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, N-0317 Oslo, Norway; (R.B.L.); (O.S.G.)
| | - Odd Stokke Gabrielsen
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, N-0317 Oslo, Norway; (R.B.L.); (O.S.G.)
| | - Christian Bindesbøll
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
| | - Stine Marie Ulven
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Hilde Irene Nebb
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Line Mariann Grønning-Wang
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (R.C.N.); (C.M.N.); (C.L.); (H.S.); (J.M.); (S.M.U.); (H.I.N.); (L.M.G.-W.)
| | - Thomas Sæther
- Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, N-0317 Oslo, Norway; (Q.F.); (K.V.); (C.B.)
- Correspondence: ; Tel.: +47-22-851510
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Viscarra J, Sul HS. Epigenetic Regulation of Hepatic Lipogenesis: Role in Hepatosteatosis and Diabetes. Diabetes 2020; 69:525-531. [PMID: 32198196 PMCID: PMC7085244 DOI: 10.2337/dbi18-0032] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 01/23/2020] [Indexed: 12/31/2022]
Abstract
Hepatosteatosis, which is frequently associated with development of metabolic syndrome and insulin resistance, manifests when triglyceride (TG) input in the liver is greater than TG output, resulting in the excess accumulation of TG. Dysregulation of lipogenesis therefore has the potential to increase lipid accumulation in the liver, leading to insulin resistance and type 2 diabetes. Recently, efforts have been made to examine the epigenetic regulation of metabolism by histone-modifying enzymes that alter chromatin accessibility for activation or repression of transcription. For regulation of lipogenic gene transcription, various known lipogenic transcription factors, such as USF1, ChREBP, and LXR, interact with and recruit specific histone modifiers, directing specificity toward lipogenesis. Alteration or impairment of the functions of these histone modifiers can lead to dysregulation of lipogenesis and thus hepatosteatosis leading to insulin resistance and type 2 diabetes.
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Affiliation(s)
- Jose Viscarra
- Nutritional Science and Toxicology, University of California, Berkeley, Berkeley, CA
| | - Hei Sook Sul
- Nutritional Science and Toxicology, University of California, Berkeley, Berkeley, CA
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29
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Zhang X, Xie X, Heckmann BL, Saarinen AM, Gu H, Zechner R, Liu J. Identification of an intrinsic lysophosphatidic acid acyltransferase activity in the lipolytic inhibitor G 0/G 1 switch gene 2 (G0S2). FASEB J 2019; 33:6655-6666. [PMID: 30802154 PMCID: PMC6463910 DOI: 10.1096/fj.201802502r] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
G0/G1 switch gene 2 (G0S2) is a specific inhibitor of adipose triglyceride lipase (ATGL), the rate-limiting enzyme for intracellular lipolysis. Recent studies show that G0S2 plays a critical role in promoting triacylglycerol (TG) accumulation in the liver, and its encoding gene is a direct target of a major lipogenic transcription factor liver X receptor (LXR)α. Here we sought to investigate a lipolysis-independent role of G0S2 in hepatic triglyceride synthesis. Knockdown of G0S2 decreased hepatic TG content in mice with ATGL ablation. Conversely, overexpression of G0S2 promoted fatty acid incorporation into TGs and diacylglycerols in both wild-type and ATGL-deficient hepatocytes. Biochemical characterization showed that G0S2 mediates phosphatidic acid synthesis from lysophosphatidic acid (LPA) and acyl-coenzyme A. In response to a high-sucrose lipogenic diet, G0S2 is up-regulated via LXRα and required for the increased TG accumulation in liver. Furthermore, deletion of a distinct 4-aa motif necessary for the LPA-specific acyltransferase (LPAAT) activity impaired G0S2's ability to mediate TG synthesis both in vitro and in vivo. These studies identify G0S2 as a dual-function regulator of lipid metabolism as well as a novel mechanism whereby hepatic TG storage is promoted in response to lipogenic stimulation. In addition to its role as a lipolytic inhibitor, G0S2 is capable of directly promoting TG synthesis by acting as a lipid-synthesizing enzyme.-Zhang, X., Xie, X., Heckmann, B. L., Saarinen, A. M., Gu, H., Zechner, R., Liu, J. Identification of an intrinsic lysophosphatidic acid acyltransferase activity in the lipolytic inhibitor G0/G1 switch gene 2 (G0S2).
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Affiliation(s)
- Xiaodong Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Xitao Xie
- Department of Chemical Engineering, Arizona State University, Tempe, Arizona, USA
| | - Bradlee L. Heckmann
- Department of Immunology, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Alicia M. Saarinen
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA
| | - Haiwei Gu
- Center for Metabolic and Vascular Biology, College of Health Solutions, Arizona State University, Scottsdale, Arizona, USA
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Jun Liu
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA;,Division of Endocrinology, Mayo Clinic College of Medicine and Science, Rochester, Minnesota, USA,Correspondence: Mayo Clinic College of Medicine and Science, Guggenheim Building 14-05, 222 3rd Ave. SW, Rochester, MN 55905, USA. E-mail:
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Lian J, Watts R, Quiroga AD, Beggs MR, Alexander RT, Lehner R. Ces1d deficiency protects against high-sucrose diet-induced hepatic triacylglycerol accumulation. J Lipid Res 2019; 60:880-891. [PMID: 30737251 PMCID: PMC6446703 DOI: 10.1194/jlr.m092544] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Indexed: 12/20/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Triacylglycerol accumulation in the liver is a hallmark of NAFLD. Metabolic studies have confirmed that increased hepatic de novo lipogenesis (DNL) in humans contributes to fat accumulation in the liver and to NAFLD progression. Mice deficient in carboxylesterase (Ces)1d expression are protected from high-fat diet-induced hepatic steatosis. To investigate whether loss of Ces1d can also mitigate steatosis induced by over-activated DNL, WT and Ces1d-deficient mice were fed a lipogenic high-sucrose diet (HSD). We found that Ces1d-deficient mice were protected from HSD-induced hepatic lipid accumulation. Mechanistically, Ces1d deficiency leads to activation of AMP-activated protein kinase and inhibitory phosphorylation of acetyl-CoA carboxylase. Together with our previous demonstration that Ces1d deficiency attenuated high-fat diet-induced steatosis, this study suggests that inhibition of CES1 (the human ortholog of Ces1d) might represent a novel pharmacological target for prevention and treatment of NAFLD.
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Affiliation(s)
- Jihong Lian
- Group on Molecular and Cell Biology of Lipids University of Alberta, Alberta, Canada; Departments of Pediatrics, University of Alberta, Alberta, Canada
| | - Russell Watts
- Group on Molecular and Cell Biology of Lipids University of Alberta, Alberta, Canada; Departments of Pediatrics, University of Alberta, Alberta, Canada
| | - Ariel D Quiroga
- Instituto de Fisiología Experimental (IFISE), Área Morfología, Facultad de Ciencias Bioquímicas y Farmacéuticas, CONICET, UNR, Rosario, Argentina
| | | | - R Todd Alexander
- Departments of Pediatrics, University of Alberta, Alberta, Canada; Physiology, University of Alberta, Alberta, Canada
| | - Richard Lehner
- Group on Molecular and Cell Biology of Lipids University of Alberta, Alberta, Canada; Departments of Pediatrics, University of Alberta, Alberta, Canada; Cell Biology, University of Alberta, Alberta, Canada.
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Abstract
In the early 1980s, while using purified glycosyltransferases to probe glycan structures on surfaces of living cells in the murine immune system, we discovered a novel form of serine/threonine protein glycosylation (O-linked β-GlcNAc; O-GlcNAc) that occurs on thousands of proteins within the nucleus, cytoplasm, and mitochondria. Prior to this discovery, it was dogma that protein glycosylation was restricted to the luminal compartments of the secretory pathway and on extracellular domains of membrane and secretory proteins. Work in the last 3 decades from several laboratories has shown that O-GlcNAc cycling serves as a nutrient sensor to regulate signaling, transcription, mitochondrial activity, and cytoskeletal functions. O-GlcNAc also has extensive cross-talk with phosphorylation, not only at the same or proximal sites on polypeptides, but also by regulating each other's enzymes that catalyze cycling of the modifications. O-GlcNAc is generally not elongated or modified. It cycles on and off polypeptides in a time scale similar to phosphorylation, and both the enzyme that adds O-GlcNAc, the O-GlcNAc transferase (OGT), and the enzyme that removes O-GlcNAc, O-GlcNAcase (OGA), are highly conserved from C. elegans to humans. Both O-GlcNAc cycling enzymes are essential in mammals and plants. Due to O-GlcNAc's fundamental roles as a nutrient and stress sensor, it plays an important role in the etiologies of chronic diseases of aging, including diabetes, cancer, and neurodegenerative disease. This review will present an overview of our current understanding of O-GlcNAc's regulation, functions, and roles in chronic diseases of aging.
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Affiliation(s)
- Gerald W Hart
- From the Complex Carbohydrate Research Center and Biochemistry and Molecular Biology Department, University of Georgia, Athens, Georgia 30602
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O-GlcNAc site-mapping of liver X receptor-α and O-GlcNAc transferase. Biochem Biophys Res Commun 2018; 499:354-360. [PMID: 29577901 DOI: 10.1016/j.bbrc.2018.03.164] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 03/21/2018] [Indexed: 01/17/2023]
Abstract
The Liver X Receptor α (LXRα) belongs to the nuclear receptor superfamily and plays an essential role in regulating cholesterol, lipid and glucose metabolism and inflammatory responses. We have previously shown that LXRα is post-translationally modified by O-linked β-N-acetyl-glucosamine (O-GlcNAc) with increased transcriptional activity. Moreover, we showed that LXRα associates with O-GlcNAc transferase (OGT) in vitro and in vivo in mouse liver. In this study, we report that human LXRα is O-GlcNAc modified in its N-terminal domain (NTD) by identifying a specific O-GlcNAc site S49 and a novel O-GlcNAc modified peptide 20LWKPGAQDASSQAQGGSSCILRE42. However, O-GlcNAc site-mutations did not modulate LXRα transactivation of selected target gene promoters in vitro. Peptide array and co-immunoprecipitation assays demonstrate that LXRα interacts with OGT in its NTD and ligand-binding domain (LBD) in a ligand-independent fashion. Moreover, we map two new O-GlcNAc sites in the longest OGT isoform (ncOGT): S437 in the tetratricopeptide repeat (TPR) 13 domain and T1043 in the far C-terminus, and a new O-GlcNAc modified peptide (amino acids 826-832) in the intervening region (Int-D) within the catalytic domain. We also map four new O-GlcNAc sites in the short isoform sOGT: S391, T393, S399 and S437 in the TPRs 11-13 domain. Future studies will reveal the biological role of identified O-GlcNAc sites in LXRα and OGT.
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Zenata O, Vrzal R. Fine tuning of vitamin D receptor (VDR) activity by post-transcriptional and post-translational modifications. Oncotarget 2018; 8:35390-35402. [PMID: 28427151 PMCID: PMC5471063 DOI: 10.18632/oncotarget.15697] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/08/2017] [Indexed: 12/31/2022] Open
Abstract
Vitamin D receptor (VDR) is a member of the nuclear receptor (NR) superfamily of ligand-activated transcription factors. Activated VDR is responsible for maintaining calcium and phosphate homeostasis, and is required for proper cellular growth, cell differentiation and apoptosis. The expression of both phases I and II drug-metabolizing enzymes is also regulated by VDR, therefore it is clinically important. Post-translational modifications of NRs have been known as an important mechanism modulating the activity of NRs and their ability to drive the expression of target genes. The aim of this mini review is to summarize the current knowledge about post-transcriptional and post-translational modifications of VDR.
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Affiliation(s)
- Ondrej Zenata
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Olomouc, Czech Republic
| | - Radim Vrzal
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Olomouc, Czech Republic
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Kim MJ, Choi MY, Lee DH, Roh GS, Kim HJ, Kang SS, Cho GJ, Kim YS, Choi WS. O-linked N-acetylglucosamine transferase enhances secretory clusterin expression via liver X receptors and sterol response element binding protein regulation in cervical cancer. Oncotarget 2017; 9:4625-4636. [PMID: 29435130 PMCID: PMC5797001 DOI: 10.18632/oncotarget.23588] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 12/04/2017] [Indexed: 01/09/2023] Open
Abstract
O-linked N-acetylglucosamine transferase (OGT) expression is increased in various cancer types, indicating the potential importance of O-GlcNAcylation in tumorigenesis. Secretory clusterin (sCLU) is involved in cancer cell proliferation and drug resistance, and recently, liver X receptors (LXRs) and sterol response element binding protein-1 (SREBP-1) were reported to regulate sCLU transcription. Here, we found that sCLU is significantly increased in cervical cancer cell lines, which have higher expression levels of O-GlcNAc and OGT than keratinocytes. OGT knockdown decreased expression of LXRs, SREBP-1 and sCLU through hypo-O-GlcNAcylation of LXRs. Additionally, treatment with Thiamet G, O-GlcNAcase OGA inhibitor, increased expression of O-GlcNAcylation and sCLU, and high glucose increased levels of LXRs, SREBP-1 and sCLU in HeLa cells. Moreover, OGT knockdown induced G0/G1 phase cell cycle arrest and late apoptosis in cisplatin-treated HeLa cells, and decreased viability compared to OGT intact HeLa cells. Taken together, these findings suggest that OGT, O-GlcNAcylated LXRs, and SREBP-1 increase sCLU expression in cervical cancer cells, which contributes to drug resistance.
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Affiliation(s)
- Min Jun Kim
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Mee Young Choi
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Dong Hoon Lee
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Gu Seob Roh
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Hyun Joon Kim
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Sang Soo Kang
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Gyeong Jae Cho
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Yoon Sook Kim
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
| | - Wan Sung Choi
- Department of Anatomy and Convergence Medical Science, Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju, Gyeongnam, Republic of Korea
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Peng L, Zhao XS, Peng D. Anti-obesity Effect of a Novel Potent Synthetic Steroidal Liver X Receptor α (LXRα)-selective Agonist in Male ob/ob C57BL/6 Mice. INT J PHARMACOL 2017. [DOI: 10.3923/ijp.2017.636.642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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LXRα Regulates Hepatic ChREBPα Activity and Lipogenesis upon Glucose, but Not Fructose Feeding in Mice. Nutrients 2017; 9:nu9070678. [PMID: 28661453 PMCID: PMC5537793 DOI: 10.3390/nu9070678] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/15/2017] [Accepted: 06/26/2017] [Indexed: 12/16/2022] Open
Abstract
Liver X receptors (LXRα/β) and carbohydrate response element-binding proteins (ChREBPα/β) are key players in the transcriptional control of hepatic de novo lipogenesis. LXRα/β double knockout (LXRα−/−/β−/−) mice have reduced feeding-induced nuclear O-linked N-acetylglucosamine (O-GlcNAc) signaling, ChREBPα activity, and lipogenic gene expression in livers, suggesting important roles for LXRs in linking hepatic glucose utilization to lipid synthesis. However, the role of LXRs in fructose-induced ChREBP activation and lipogenesis is currently unknown. In this study, we studied the effects of high fructose or high glucose feeding on hepatic carbohydrate metabolism and lipogenic gene expression in livers from fasted (24 h) and fasted-refed (12 h) wild type and LXRα knockout (LXRα−/−) mice. Hepatic lipogenic gene expression was reduced in glucose fed, but not fructose fed LXRα−/− mice. This was associated with lower expression of liver pyruvate-kinase (L-pk) and Chrebpβ, indicating reduced ChREBPα activity in glucose fed, but not fructose fed mice. Interestingly, ChREBP binding to the L-pk promoter was increased in fructose fed LXRα−/− mice, concomitant with increased glucose-6-phosphatase (G6pc) expression and O-GlcNAc modified LXRβ, suggesting a role for LXRβ in regulating ChREBPα activity upon fructose feeding. In conclusion, we propose that LXRα is an important regulator of hepatic lipogenesis and ChREBPα activity upon glucose, but not fructose feeding in mice.
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Delgado MJ, Cerdá-Reverter JM, Soengas JL. Hypothalamic Integration of Metabolic, Endocrine, and Circadian Signals in Fish: Involvement in the Control of Food Intake. Front Neurosci 2017; 11:354. [PMID: 28694769 PMCID: PMC5483453 DOI: 10.3389/fnins.2017.00354] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 06/07/2017] [Indexed: 12/12/2022] Open
Abstract
The regulation of food intake in fish is a complex process carried out through several different mechanisms in the central nervous system (CNS) with hypothalamus being the main regulatory center. As in mammals, a complex hypothalamic circuit including two populations of neurons: one co-expressing neuropeptide Y (NPY) and Agouti-related peptide (AgRP) and the second one population co-expressing pro-opiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART) is involved in the integration of information relating to food intake control. The production and release of these peptides control food intake, and the production results from the integration of information of different nature such as levels of nutrients and hormones as well as circadian signals. The present review summarizes the knowledge and recent findings about the presence and functioning of these mechanisms in fish and their differences vs. the known mammalian model.
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Affiliation(s)
- María J. Delgado
- Departamento de Fisiología (Fisiología Animal II), Facultad de Biología, Universidad Complutense de MadridMadrid, Spain
| | - José M. Cerdá-Reverter
- Departamento de Fisiología de Peces y Biotecnología, Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones CientíficasCastellón, Spain
| | - José L. Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de VigoVigo, Spain
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38
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Abd Eldaim MA, Matsuoka S, Okamatsu-Ogura Y, Kamikawa A, Ahmed MM, Terao A, Nakajima KI, Kimura K. Retinoic acid modulates lipid accumulation glucose concentration dependently through inverse regulation of SREBP-1 expression in 3T3L1 adipocytes. Genes Cells 2017; 22:568-582. [PMID: 28488421 DOI: 10.1111/gtc.12498] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 03/29/2017] [Indexed: 12/19/2022]
Abstract
It is well known that retinoic acid (RA) suppresses adipogenesis, although there are some contradicting reports. In this study, we examined the effect of extracellular glucose on RA-induced suppression of adipogenesis in 3T3L1 cell culture. When the cells were cultured in normal glucose medium (NG), the addition of RA suppressed lipid accumulation. However, when cultured in high glucose medium (HG), addition of RA to the cells enhanced lipid accumulation. These changes were accompanied by parallel alterations in fatty acid synthase (FAS) and sterol regulatory element-binding protein (SREBP)-1 gene expression. Transfection of SREBP-1 siRNA suppressed RA-induced enhancement of lipid accumulation and FAS expression in the cells cultured with HG. Transfection of the nuclear form of SREBP-1a cDNA into the cells cultured with NG inhibited RA-induced suppression of lipid accumulation and FAS expression. Moreover, RA- and HG-induced SREBP-1a expression occurred at the early phase of adipogenesis and was dependent on glucocorticoid to induce liver X receptor (LXR) β, peroxisomal proliferator-activated receptor (PPAR) γ and retinoid X receptor (RXR), the key nuclear factors influencing the SREBP-1a gene expression. These results suggest that RA suppresses and enhances lipid accumulation through extracellular glucose concentration-dependent modulation of SREBP-1 expression.
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Affiliation(s)
- Mabrouk Attia Abd Eldaim
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan.,Department of Biochemistry and Chemistry of Nutrition, Faculty of Veterinary Medicine, Menoufia University, Menoufia, 32721, Egypt
| | - Shinya Matsuoka
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan
| | - Yuko Okamatsu-Ogura
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan
| | - Akihiro Kamikawa
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan
| | - Mohamed Mohamed Ahmed
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan
| | - Akira Terao
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan
| | - Kei-Ichi Nakajima
- National Agricultural Research Center for Hokkaido Region, Sapporo, 062-8555, Japan
| | - Kazuhiro Kimura
- Laboratories of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, 060-0818, Japan
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39
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Heckmann BL, Zhang X, Saarinen AM, Schoiswohl G, Kershaw EE, Zechner R, Liu J. Liver X receptor α mediates hepatic triglyceride accumulation through upregulation of G0/G1 Switch Gene 2 expression. JCI Insight 2017; 2:e88735. [PMID: 28239648 DOI: 10.1172/jci.insight.88735] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Liver X receptors (LXRs) are transcription factors essential for cholesterol homeostasis and lipogenesis. LXRα has been implicated in regulating hepatic triglyceride (TG) accumulation upon both influx of adipose-derived fatty acids (FAs) during fasting and stimulation of de novo FA synthesis by chemical agonism of LXR. However, whether or not a convergent mechanism is employed to drive deposition of FAs from these 2 different sources in TGs is undetermined. Here, we report that the G0/G1 Switch Gene 2 (G0S2), a selective inhibitor of intracellular TG hydrolysis/lipolysis, is a direct target gene of LXRα. Transcriptional activation is conferred by LXRα binding to a direct repeat 4 (DR4) motif in the G0S2 promoter. While LXRα-/- mice exhibited decreased hepatic G0S2 expression, adenoviral expression of G0S2 was sufficient to restore fasting-induced TG storage and glycogen depletion in the liver of these mice. In response to LXR agonist T0901317, G0S2 ablation prevented hepatic steatosis and hypertriglyceridemia without affecting the beneficial effects on HDL. Thus, the LXRα-G0S2 axis plays a distinct role in regulating hepatic TG during both fasting and pharmacological activation of LXR.
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Affiliation(s)
- Bradlee L Heckmann
- Department of Biochemistry and Molecular Biology.,HEALth Program, Mayo Clinic in Arizona, Scottsdale, Arizona, USA.,Mayo Graduate School, Rochester, Minnesota, USA
| | - Xiaodong Zhang
- Department of Biochemistry and Molecular Biology.,HEALth Program, Mayo Clinic in Arizona, Scottsdale, Arizona, USA
| | - Alicia M Saarinen
- Department of Biochemistry and Molecular Biology.,HEALth Program, Mayo Clinic in Arizona, Scottsdale, Arizona, USA
| | - Gabriele Schoiswohl
- Division of Endocrinology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Erin E Kershaw
- Division of Endocrinology, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Jun Liu
- Department of Biochemistry and Molecular Biology.,HEALth Program, Mayo Clinic in Arizona, Scottsdale, Arizona, USA.,Division of Endocrinology, Mayo Clinic in Arizona, Scottsdale, Arizona, USA
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Becares N, Gage MC, Pineda-Torra I. Posttranslational Modifications of Lipid-Activated Nuclear Receptors: Focus on Metabolism. Endocrinology 2017; 158:213-225. [PMID: 27925773 PMCID: PMC5413085 DOI: 10.1210/en.2016-1577] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 12/02/2016] [Indexed: 12/18/2022]
Abstract
Posttranslational modifications (PTMs) occur to nearly all proteins, are catalyzed by specific enzymes, and are subjected to tight regulation. They have been shown to be a powerful means by which the function of proteins can be modified, resulting in diverse effects. Technological advances such as the increased sensitivity of mass spectrometry-based techniques and availability of mutant animal models have enhanced our understanding of the complexities of their regulation and the effect they have on protein function. However, the role that PTMs have in a pathological context still remains unknown for the most part. PTMs enable the modulation of nuclear receptor function in a rapid and reversible manner in response to varied stimuli, thereby dramatically altering their activity in some cases. This review focuses on acetylation, phosphorylation, SUMOylation, and O-GlcNAcylation, which are the 4 most studied PTMs affecting lipid-regulated nuclear receptor biology, as well as on the implications of such modifications on metabolic pathways under homeostatic and pathological situations. Moreover, we review recent studies on the modulation of PTMs as therapeutic targets for metabolic diseases.
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Affiliation(s)
- Natalia Becares
- Centre for Clinical Pharmacology, Division of Medicine, University College of London, London, United Kingdom
| | - Matthew C Gage
- Centre for Clinical Pharmacology, Division of Medicine, University College of London, London, United Kingdom
| | - Inés Pineda-Torra
- Centre for Clinical Pharmacology, Division of Medicine, University College of London, London, United Kingdom
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41
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Conde-Sieira M, Soengas JL. Nutrient Sensing Systems in Fish: Impact on Food Intake Regulation and Energy Homeostasis. Front Neurosci 2017; 10:603. [PMID: 28111540 PMCID: PMC5216673 DOI: 10.3389/fnins.2016.00603] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 12/19/2016] [Indexed: 12/27/2022] Open
Abstract
Evidence obtained in recent years in a few species, especially rainbow trout, supports the presence in fish of nutrient sensing mechanisms. Glucosensing capacity is present in central (hypothalamus and hindbrain) and peripheral [liver, Brockmann bodies (BB, main accumulation of pancreatic endocrine cells in several fish species), and intestine] locations whereas fatty acid sensors seem to be present in hypothalamus, liver and BB. Glucose and fatty acid sensing capacities relate to food intake regulation and metabolism in fish. Hypothalamus is as a signaling integratory center in a way that detection of increased levels of nutrients result in food intake inhibition through changes in the expression of anorexigenic and orexigenic neuropeptides. Moreover, central nutrient sensing modulates functions in the periphery since they elicit changes in hepatic metabolism as well as in hormone secretion to counter-regulate changes in nutrient levels detected in the CNS. At peripheral level, the direct nutrient detection in liver has a crucial role in homeostatic control of glucose and fatty acid whereas in BB and intestine nutrient sensing is probably involved in regulation of hormone secretion from endocrine cells.
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Affiliation(s)
- Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo Vigo, Spain
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42
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In vitro evidence in rainbow trout supporting glucosensing mediated by sweet taste receptor, LXR, and mitochondrial activity in Brockmann bodies, and sweet taste receptor in liver. Comp Biochem Physiol B Biochem Mol Biol 2016; 200:6-16. [DOI: 10.1016/j.cbpb.2016.04.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 04/25/2016] [Accepted: 04/27/2016] [Indexed: 12/31/2022]
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43
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Glucosensing in liver and Brockmann bodies of rainbow trout through glucokinase-independent mechanisms. Comp Biochem Physiol B Biochem Mol Biol 2016; 199:29-42. [DOI: 10.1016/j.cbpb.2015.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/17/2015] [Accepted: 09/25/2015] [Indexed: 01/21/2023]
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44
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Lee JH, Kim H, Park SJ, Woo JH, Joe EH, Jou I. Small heterodimer partner SHP mediates liver X receptor (LXR)–dependent suppression of inflammatory signaling by promoting LXR SUMOylation specifically in astrocytes. Sci Signal 2016; 9:ra78. [DOI: 10.1126/scisignal.aaf4850] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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45
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Baldini SF, Wavelet C, Hainault I, Guinez C, Lefebvre T. The Nutrient-Dependent O -GlcNAc Modification Controls the Expression of Liver Fatty Acid Synthase. J Mol Biol 2016; 428:3295-3304. [DOI: 10.1016/j.jmb.2016.04.035] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 04/27/2016] [Accepted: 04/29/2016] [Indexed: 12/13/2022]
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46
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Wang Y, Viscarra J, Kim SJ, Sul HS. Transcriptional regulation of hepatic lipogenesis. Nat Rev Mol Cell Biol 2016; 16:678-89. [PMID: 26490400 DOI: 10.1038/nrm4074] [Citation(s) in RCA: 453] [Impact Index Per Article: 56.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fatty acid and fat synthesis in the liver is a highly regulated metabolic pathway that is important for very low-density lipoprotein (VLDL) production and thus energy distribution to other tissues. Having common features at their promoter regions, lipogenic genes are coordinately regulated at the transcriptional level. Transcription factors, such as upstream stimulatory factors (USFs), sterol regulatory element-binding protein 1C (SREBP1C), liver X receptors (LXRs) and carbohydrate-responsive element-binding protein (ChREBP) have crucial roles in this process. Recently, insights have been gained into the signalling pathways that regulate these transcription factors. After feeding, high blood glucose and insulin levels activate lipogenic genes through several pathways, including the DNA-dependent protein kinase (DNA-PK), atypical protein kinase C (aPKC) and AKT-mTOR pathways. These pathways control the post-translational modifications of transcription factors and co-regulators, such as phosphorylation, acetylation or ubiquitylation, that affect their function, stability and/or localization. Dysregulation of lipogenesis can contribute to hepatosteatosis, which is associated with obesity and insulin resistance.
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Affiliation(s)
- Yuhui Wang
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
| | - Jose Viscarra
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
| | - Sun-Joong Kim
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
| | - Hei Sook Sul
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
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47
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Otero-Rodiño C, Velasco C, Álvarez-Otero R, López-Patiño MA, Míguez JM, Soengas JL. In vitro evidence supports the presence of glucokinase-independent glucosensing mechanisms in hypothalamus and hindbrain of rainbow trout. ACTA ACUST UNITED AC 2016; 219:1750-9. [PMID: 27026717 DOI: 10.1242/jeb.137737] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 03/03/2016] [Indexed: 11/20/2022]
Abstract
We previously obtained evidence in rainbow trout for the presence and response to changes in circulating levels of glucose (induced by intraperitoneal hypoglycaemic and hyperglycaemic treatments) of glucosensing mechanisms based on liver X receptor (LXR), mitochondrial production of reactive oxygen species (ROS) leading to increased expression of uncoupling protein 2 (UCP2), and sweet taste receptor in the hypothalamus, and on sodium/glucose co-transporter 1 (SGLT-1) in hindbrain. However, these effects of glucose might be indirect. Therefore, we evaluated the response of parameters related to these glucosensing mechanisms in a first experiment using pooled sections of hypothalamus and hindbrain incubated for 6 h at 15°C in modified Hanks' medium containing 2, 4 or 8 mmol l(-1) d-glucose. The responses observed in some cases were consistent with glucosensing capacity. In a second experiment, pooled sections of hypothalamus and hindbrain were incubated for 6 h at 15°C in modified Hanks' medium with 8 mmol l(-1) d-glucose alone (control) or containing 1 mmol l(-1) phloridzin (SGLT-1 antagonist), 20 µmol l(-1) genipin (UCP2 inhibitor), 1 µmol l(-1) trolox (ROS scavenger), 100 µmol l(-1) bezafibrate (T1R3 inhibitor) and 50 µmol l(-1) geranyl-geranyl pyrophosphate (LXR inhibitor). The response observed in the presence of these specific inhibitors/antagonists further supports the proposal that critical components of the different glucosensing mechanisms are functioning in rainbow trout hypothalamus and hindbrain.
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Affiliation(s)
- Cristina Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo E-36310, Spain
| | - Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo E-36310, Spain
| | - Rosa Álvarez-Otero
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo E-36310, Spain
| | - Marcos A López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo E-36310, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo E-36310, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo E-36310, Spain
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48
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Shrestha E, Hussein MA, Savas JN, Ouimet M, Barrett TJ, Leone S, Yates JR, Moore KJ, Fisher EA, Garabedian MJ. Poly(ADP-ribose) Polymerase 1 Represses Liver X Receptor-mediated ABCA1 Expression and Cholesterol Efflux in Macrophages. J Biol Chem 2016; 291:11172-84. [PMID: 27026705 DOI: 10.1074/jbc.m116.726729] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Indexed: 11/06/2022] Open
Abstract
Liver X receptors (LXR) are oxysterol-activated nuclear receptors that play a central role in reverse cholesterol transport through up-regulation of ATP-binding cassette transporters (ABCA1 and ABCG1) that mediate cellular cholesterol efflux. Mouse models of atherosclerosis exhibit reduced atherosclerosis and enhanced regression of established plaques upon LXR activation. However, the coregulatory factors that affect LXR-dependent gene activation in macrophages remain to be elucidated. To identify novel regulators of LXR that modulate its activity, we used affinity purification and mass spectrometry to analyze nuclear LXRα complexes and identified poly(ADP-ribose) polymerase-1 (PARP-1) as an LXR-associated factor. In fact, PARP-1 interacted with both LXRα and LXRβ. Both depletion of PARP-1 and inhibition of PARP-1 activity augmented LXR ligand-induced ABCA1 expression in the RAW 264.7 macrophage line and primary bone marrow-derived macrophages but did not affect LXR-dependent expression of other target genes, ABCG1 and SREBP-1c. Chromatin immunoprecipitation experiments confirmed PARP-1 recruitment at the LXR response element in the promoter of the ABCA1 gene. Further, we demonstrated that LXR is poly(ADP-ribosyl)ated by PARP-1, a potential mechanism by which PARP-1 influences LXR function. Importantly, the PARP inhibitor 3-aminobenzamide enhanced macrophage ABCA1-mediated cholesterol efflux to the lipid-poor apolipoprotein AI. These findings shed light on the important role of PARP-1 on LXR-regulated lipid homeostasis. Understanding the interplay between PARP-1 and LXR may provide insights into developing novel therapeutics for treating atherosclerosis.
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Affiliation(s)
- Elina Shrestha
- From the Department of Microbiology, New York University School of Medicine, New York, New York 10016
| | - Maryem A Hussein
- From the Department of Microbiology, New York University School of Medicine, New York, New York 10016
| | - Jeffery N Savas
- the Department of Neurology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois 60611
| | - Mireille Ouimet
- the Department of Medicine, Division of Cardiology, Marc and Ruti Bell Program in Vascular Biology, New York University School of Medicine, New York, New York 10016, and
| | - Tessa J Barrett
- the Department of Medicine, Division of Cardiology, Marc and Ruti Bell Program in Vascular Biology, New York University School of Medicine, New York, New York 10016, and
| | - Sarah Leone
- From the Department of Microbiology, New York University School of Medicine, New York, New York 10016
| | - John R Yates
- the Department of Chemical Physiology, Scripps Research Institute, La Jolla, California 92037
| | - Kathryn J Moore
- the Department of Medicine, Division of Cardiology, Marc and Ruti Bell Program in Vascular Biology, New York University School of Medicine, New York, New York 10016, and
| | - Edward A Fisher
- the Department of Medicine, Division of Cardiology, Marc and Ruti Bell Program in Vascular Biology, New York University School of Medicine, New York, New York 10016, and
| | - Michael J Garabedian
- From the Department of Microbiology, New York University School of Medicine, New York, New York 10016,
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49
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TCDD-inducible poly-ADP-ribose polymerase (TIPARP/PARP7) mono-ADP-ribosylates and co-activates liver X receptors. Biochem J 2016; 473:899-910. [PMID: 26814197 DOI: 10.1042/bj20151077] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/26/2016] [Indexed: 12/27/2022]
Abstract
Members of the poly-ADP-ribose polymerase (PARP) family catalyse the ADP-ribosylation of target proteins and are known to play important roles in many cellular processes, including DNA repair, differentiation and transcription. The majority of PARPs exhibit mono-ADP-ribosyltransferase activity rather than PARP activity; however, little is known about their biological activity. In the present study, we report that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-inducible poly-ADP-ribose polymerase (TIPARP), mono-ADP-ribosylates and positively regulates liver X receptor α (LXRα) and LXRβ activity. Overexpression of TIPARP enhanced LXR-reporter gene activity. TIPARP knockdown or deletion reduced LXR regulated target gene expression levels in HepG2 cells and in Tiparp(-/-)mouse embryonic fibroblasts (MEFs) respectively. Deletion and mutagenesis studies showed that TIPARP's zinc-finger and catalytic domains were required to enhance LXR activity. Protein interaction studies using TIPARP and LXRα/β peptide arrays revealed that LXRs interacted with an N-terminal sequence (a.a. 209-236) of TIPARP, which also overlapped with a putative co-activator domain of TIPARP (a.a. 200-225). Immunofluorescence studies showed that TIPARP and LXRα or LXRβ co-localized in the nucleus.In vitroribosylation assays provided evidence that TIPARP mono-ADP-ribosylated both LXRα and LXRβ. Co-immunoprecipitation (co-IP) studies revealed that ADP-ribosylase macrodomain 1 (MACROD1), but not MACROD2, interacted with LXRs in a TIPARP-dependent manner. This was complemented by reporter gene studies showing that MACROD1, but not MACROD2, prevented the TIPARP-dependent increase in LXR activity. GW3965-dependent increases in hepatic Srebp1 mRNA and protein expression levels were reduced in Tiparp(-/-)mice compared with Tiparp(+/+)mice. Taken together, these data identify a new mechanism of LXR regulation that involves TIPARP, ADP-ribosylation and MACROD1.
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50
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Baldini SF, Lefebvre T. O-GlcNAcylation and the Metabolic Shift in High-Proliferating Cells: All the Evidence Suggests that Sugars Dictate the Flux of Lipid Biogenesis in Tumor Processes. Front Oncol 2016; 6:6. [PMID: 26835421 PMCID: PMC4722119 DOI: 10.3389/fonc.2016.00006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 01/08/2016] [Indexed: 12/25/2022] Open
Abstract
Cancer cells are characterized by their high capability to proliferate. This imposes an accelerated biosynthesis of membrane compounds to respond to the need for increasing the membrane surface of dividing cells and remodeling the structure of lipid microdomains. Recently, attention has been paid to the upregulation of O-GlcNAcylation processes observed in cancer cells. Although O-GlcNAcylation of lipogenic transcriptional regulators is described in the literature (e.g., FXR, LXR, ChREBP), little is known about the regulation of the enzymes that drive lipogenesis: acetyl co-enzyme A carboxylase and fatty acid synthase (FAS). The expression and catalytic activity of both FAS and O-GlcNAc transferase (OGT) are high in cancer cells but the reciprocal regulation of the two enzymes remains unexplored. In this perspective, we collected data linking FAS and OGT and, in so doing, pave the way for the exploration of the intricate functions of these two actors that play a central role in tumor growth.
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Affiliation(s)
- Steffi F Baldini
- University Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle , Lille , France
| | - Tony Lefebvre
- University Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle , Lille , France
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