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Sharma AK, Khandelwal R, Wolfrum C. Futile cycles: Emerging utility from apparent futility. Cell Metab 2024; 36:1184-1203. [PMID: 38565147 DOI: 10.1016/j.cmet.2024.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/15/2024] [Accepted: 03/11/2024] [Indexed: 04/04/2024]
Abstract
Futile cycles are biological phenomena where two opposing biochemical reactions run simultaneously, resulting in a net energy loss without appreciable productivity. Such a state was presumed to be a biological aberration and thus deemed an energy-wasting "futile" cycle. However, multiple pieces of evidence suggest that biological utilities emerge from futile cycles. A few established functions of futile cycles are to control metabolic sensitivity, modulate energy homeostasis, and drive adaptive thermogenesis. Yet, the physiological regulation, implication, and pathological relevance of most futile cycles remain poorly studied. In this review, we highlight the abundance and versatility of futile cycles and propose a classification scheme. We further discuss the energetic implications of various futile cycles and their impact on basal metabolic rate, their bona fide and tentative pathophysiological implications, and putative drug interactions.
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Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
| | - Radhika Khandelwal
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Christian Wolfrum
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
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Sharma AK, Khandelwal R, Wolfrum C. Futile lipid cycling: from biochemistry to physiology. Nat Metab 2024; 6:808-824. [PMID: 38459186 DOI: 10.1038/s42255-024-01003-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 02/02/2024] [Indexed: 03/10/2024]
Abstract
In the healthy state, the fat stored in our body isn't just inert. Rather, it is dynamically mobilized to maintain an adequate concentration of fatty acids (FAs) in our bloodstream. Our body tends to produce excess FAs to ensure that the FA availability is not limiting. The surplus FAs are actively re-esterified into glycerides, initiating a cycle of breakdown and resynthesis of glycerides. This cycle consumes energy without generating a new product and is commonly referred to as the 'futile lipid cycle' or the glyceride/FA cycle. Contrary to the notion that it's a wasteful process, it turns out this cycle is crucial for systemic metabolic homeostasis. It acts as a control point in intra-adipocyte and inter-organ cross-talk, a metabolic rheostat, an energy sensor and a lipid diversifying mechanism. In this Review, we discuss the metabolic regulation and physiological implications of the glyceride/FA cycle and its mechanistic underpinnings.
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Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
| | - Radhika Khandelwal
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Christian Wolfrum
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
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3
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Krumm CS, Landzberg RS, Ramos-Espiritu L, Adura C, Liu X, Acuna M, Xie Y, Xu X, Tillman MC, Li Y, Glickman JF, Ortlund EA, Ginn JD, Cohen DE. High-throughput screening identifies small molecule inhibitors of thioesterase superfamily member 1: Implications for the management of non-alcoholic fatty liver disease. Mol Metab 2023; 78:101832. [PMID: 38403978 PMCID: PMC10663673 DOI: 10.1016/j.molmet.2023.101832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 02/27/2024] Open
Abstract
OBJECTIVE Thioesterase superfamily member 1 (Them1) is a long chain acyl-CoA thioesterase comprising two N-terminal HotDog fold enzymatic domains linked to a C-terminal lipid-sensing steroidogenic acute regulatory transfer-related (START) domain, which allosterically modulates enzymatic activity. Them1 is highly expressed in thermogenic adipose tissue, where it functions to suppress energy expenditure by limiting rates of fatty acid oxidation, and is induced markedly in liver in response to high fat feeding, where it suppresses fatty acid oxidation and promotes glucose production. Them1-/- mice are protected against non-alcoholic fatty liver disease (NAFLD), suggesting Them1 as a therapeutic target. METHODS A high-throughput small molecule screen was performed to identify promising inhibitors targeting the fatty acyl-CoA thioesterase activity of purified recombinant Them1.Counter screening was used to determine specificity for Them1 relative to other acyl-CoA thioesterase isoforms. Inhibitor binding and enzyme inhibition were quantified by biophysical and biochemical approaches, respectively. Following structure-based optimization, lead compounds were tested in cell culture. RESULTS Two lead allosteric inhibitors were identified that selectively inhibited Them1 by binding the START domain. In mouse brown adipocytes, these inhibitors promoted fatty acid oxidation, as evidenced by increased oxygen consumption rates. In mouse hepatocytes, they promoted fatty acid oxidation, but also reduced glucose production. CONCLUSION Them1 inhibitors could prove attractive for the pharmacologic management of NAFLD.
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Affiliation(s)
- Christopher S Krumm
- Division of Gastroenterology & Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA; Sanders Tri-Institutional Therapeutics Discovery Institute, New York, NY 10065, USA
| | - Renée S Landzberg
- Division of Gastroenterology & Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | | | - Carolina Adura
- Fisher Drug Discovery Resource Center, The Rockefeller University, New York, NY 10065, USA
| | - Xu Liu
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Mariana Acuna
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Yang Xie
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Xu Xu
- Division of Gastroenterology & Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA; Division of Surgical Sciences, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Matthew C Tillman
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Yingxia Li
- Division of Gastroenterology & Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA
| | - J Fraser Glickman
- Fisher Drug Discovery Resource Center, The Rockefeller University, New York, NY 10065, USA
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - John D Ginn
- Sanders Tri-Institutional Therapeutics Discovery Institute, New York, NY 10065, USA
| | - David E Cohen
- Division of Gastroenterology & Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
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4
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Haczeyni F, Steensels S, Stein BD, Jordan JM, Li L, Dartigue V, Sarklioglu SS, Qiao J, Zhou XK, Dannenberg AJ, Iyengar NM, Yu H, Cantley LC, Ersoy BA. Submitochondrial Protein Translocation Upon Stress Inhibits Thermogenic Energy Expenditure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.04.539294. [PMID: 37205525 PMCID: PMC10187325 DOI: 10.1101/2023.05.04.539294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Mitochondria-rich brown adipocytes dissipate cellular fuel as heat by thermogenic energy expenditure (TEE). Prolonged nutrient excess or cold exposure impair TEE and contribute to the pathogenesis of obesity, but the mechanisms remain incompletely understood. Here we report that stress-induced proton leak into the matrix interface of mitochondrial innermembrane (IM) mobilizes a group of proteins from IM into matrix, which in turn alter mitochondrial bioenergetics. We further determine a smaller subset that correlates with obesity in human subcutaneous adipose tissue. We go on to show that the top factor on this short list, acyl-CoA thioesterase 9 (ACOT9), migrates from the IM into the matrix upon stress where it enzymatically deactivates and prevents the utilization of acetyl-CoA in TEE. The loss of ACOT9 protects mice against the complications of obesity by maintaining unobstructed TEE. Overall, our results introduce aberrant protein translocation as a strategy to identify pathogenic factors. One-Sentence Summary Thermogenic stress impairs mitochondrial energy utilization by forcing translocation of IM-bound proteins into the matrix.
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Celik C, Lee SYT, Yap WS, Thibault G. Endoplasmic reticulum stress and lipids in health and diseases. Prog Lipid Res 2023; 89:101198. [PMID: 36379317 DOI: 10.1016/j.plipres.2022.101198] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 11/03/2022] [Accepted: 11/09/2022] [Indexed: 11/14/2022]
Abstract
The endoplasmic reticulum (ER) is a complex and dynamic organelle that regulates many cellular pathways, including protein synthesis, protein quality control, and lipid synthesis. When one or multiple ER roles are dysregulated and saturated, the ER enters a stress state, which, in turn, activates the highly conserved unfolded protein response (UPR). By sensing the accumulation of unfolded proteins or lipid bilayer stress (LBS) at the ER, the UPR triggers pathways to restore ER homeostasis and eventually induces apoptosis if the stress remains unresolved. In recent years, it has emerged that the UPR works intimately with other cellular pathways to maintain lipid homeostasis at the ER, and so does at cellular levels. Lipid distribution, along with lipid anabolism and catabolism, are tightly regulated, in part, by the ER. Dysfunctional and overwhelmed lipid-related pathways, independently or in combination with ER stress, can have reciprocal effects on other cellular functions, contributing to the development of diseases. In this review, we summarize the current understanding of the UPR in response to proteotoxic stress and LBS and the breadth of the functions mitigated by the UPR in different tissues and in the context of diseases.
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Affiliation(s)
- Cenk Celik
- School of Biological Sciences, Nanyang Technological University, Singapore
| | | | - Wei Sheng Yap
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - Guillaume Thibault
- School of Biological Sciences, Nanyang Technological University, Singapore; Mechanobiology Institute, National University of Singapore, Singapore; Institute of Molecular and Cell Biology, A*STAR, Singapore.
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6
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Cheng Z, Luo X, Zhu Z, Huang Y, Yan X. Furfural Produces Dose-Dependent Attenuating Effects on Ethanol-Induced Toxicity in the Liver. Front Pharmacol 2022; 13:906933. [PMID: 35754511 PMCID: PMC9214037 DOI: 10.3389/fphar.2022.906933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/12/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Alcohol-associated liver disease (ALD) increases the health burden worldwide, but effective drugs to prevent ALD are lacking. Furfural is a small molecule that can limit alcohol production in microorganisms and may have the capacity to attenuate ethanol-induced toxicity. Methods: Human HepG2 cells were incubated with ethanol and furfural, and cell viability, NAD+/NADH ratio, and mitochondrial function assays were performed. RNA sequencing (RNA-seq) data were used to annotate enriched pathways, and these findings were confirmed by reverse transcription-quantitative PCR (RT–qPCR) and Western blotting. C57BL/6J mice were fed a Lieber-DeCarli liquid diet. After 4 weeks, biochemical analysis of mouse serum and histological analysis of mouse livers were performed. Results: Different concentrations of furfural exerted different effects on mitochondria: low-dose furfural reduced reactive oxygen species (ROS) production, maintained mitochondrial transmembrane potential, and inhibited apoptosis pathway activation, while high-dose furfural led to the opposite effects. In mice, furfural mitigated transaminase increases and attenuated the lipid metabolism disorder that had been induced by ethanol. Conclusion: Low-dose furfural reduced ethanol-induced toxicity in the liver. Consuming food or beverages containing the appropriate level of furfural when drinking alcohol may be a convenient and useful way to prevent ALD.
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Affiliation(s)
- Zhuo Cheng
- The Department of Gastroenterology and Hepatology, Peking University Third Hospital, Beijing, China
| | - Xuanmei Luo
- National Center of Gerontology, Beijing Hospital, Beijing, China
| | - Zixin Zhu
- Department of Infectious Diseases, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Yonghui Huang
- The Department of Gastroenterology and Hepatology, Peking University Third Hospital, Beijing, China
| | - Xiue Yan
- The Department of Gastroenterology and Hepatology, Peking University Third Hospital, Beijing, China
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ChREBP-regulated lipogenesis is not required for the thermogenesis of brown adipose tissue. Int J Obes (Lond) 2022; 46:1068-1075. [PMID: 35152269 PMCID: PMC8853070 DOI: 10.1038/s41366-022-01082-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 11/08/2022]
Abstract
Objectives Brown adipose tissue (BAT) plays a critical role in energy expenditure by uncoupling protein 1 (UCP1)-mediated thermogenesis and represents an important therapeutic target for metabolic diseases. Carbohydrate response element-binding protein (ChREBP) is a key transcription factor regulating de novo lipogenesis, and its activity is associated with UCP1 expression and thermogenesis in BAT. However, the exact physiological role of endogenous ChREBP in BAT thermogenesis remains unclear. Methods We used the Cre/LoxP system to generate ChREBP BAT-specific knockout mice, and examined their BAT thermogenesis under acute cold exposure and long-term cold acclimation. Gene expression was analyzed at the mRNA and protein levels, and lipogenesis was examined by 3H-H2O incorporation assay. Results The mice lacking ChREBP specifically in BAT displayed a significant decrease in the expression levels of lipogenic genes and the activity of de novo lipogenesis in BAT after cold exposure, with UCP1 expression decreased under thermoneutral conditions or after acute cold exposure but not chronic cold acclimation. Unexpectedly, BAT-specific ChREBP deletion did not significantly affect body temperature as well as local temperature or morphology of BAT after acute cold exposure or chronic cold acclimation. Of note, ChREBP deletion mildly aggravated glucose intolerance induced by a high-fat diet. Conclusions Our work indicates that ChREBP regulates de novo lipogenesis in BAT and glucose tolerance, but is not required for non-shivering thermogenesis by BAT under acute or long-term cold exposure.
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Mills EL, Harmon C, Jedrychowski MP, Xiao H, Gruszczyk AV, Bradshaw GA, Tran N, Garrity R, Laznik-Bogoslavski D, Szpyt J, Prendeville H, Lynch L, Murphy MP, Gygi SP, Spiegelman BM, Chouchani ET. Cysteine 253 of UCP1 regulates energy expenditure and sex-dependent adipose tissue inflammation. Cell Metab 2022; 34:140-157.e8. [PMID: 34861155 PMCID: PMC8732317 DOI: 10.1016/j.cmet.2021.11.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 09/15/2021] [Accepted: 11/08/2021] [Indexed: 01/07/2023]
Abstract
Uncoupling protein 1 (UCP1) is a major regulator of brown and beige adipocyte energy expenditure and metabolic homeostasis. However, the widely employed UCP1 loss-of-function model has recently been shown to have a severe deficiency in the entire electron transport chain of thermogenic fat. As such, the role of UCP1 in metabolic regulation in vivo remains unclear. We recently identified cysteine-253 as a regulatory site on UCP1 that elevates protein activity upon covalent modification. Here, we examine the physiological importance of this site through the generation of a UCP1 cysteine-253-null (UCP1 C253A) mouse, a precise genetic model for selective disruption of UCP1 in vivo. UCP1 C253A mice exhibit significantly compromised thermogenic responses in both males and females but display no measurable effect on fat accumulation in an obesogenic environment. Unexpectedly, we find that a lack of C253 results in adipose tissue redox stress, which drives substantial immune cell infiltration and systemic inflammatory pathology in adipose tissues and liver of male, but not female, mice. Elevation of systemic estrogen reverses this male-specific pathology, providing a basis for protection from inflammation due to loss of UCP1 C253 in females. Together, our results establish the UCP1 C253 activation site as a regulator of acute thermogenesis and sex-dependent tissue inflammation.
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Affiliation(s)
- Evanna L Mills
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Cathal Harmon
- Department of Immunology, Harvard Medical School, Boston, MA, USA; Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital and Harvard Medical School, Boston, USA
| | - Mark P Jedrychowski
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Haopeng Xiao
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Anja V Gruszczyk
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Gary A Bradshaw
- Harvard Program in Therapeutic Science, Harvard Medical School, Boston, MA, USA
| | - Nhien Tran
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Ryan Garrity
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | | | - John Szpyt
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Hannah Prendeville
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| | - Lydia Lynch
- Department of Immunology, Harvard Medical School, Boston, MA, USA; Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital and Harvard Medical School, Boston, USA; School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
| | - Michael P Murphy
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Bruce M Spiegelman
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Edward T Chouchani
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
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Transcriptome Profiles of the Liver in Two Cold-Exposed Sheep Breeds Revealed Different Mechanisms and Candidate Genes for Thermogenesis. Genet Res (Camb) 2021; 2021:5510297. [PMID: 36017327 PMCID: PMC9364924 DOI: 10.1155/2021/5510297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 07/29/2021] [Indexed: 11/23/2022] Open
Abstract
Cold-induced thermogenesis plays an important role in the survival of lambs exposed to
low air temperatures. The liver produces and mediates heat production in mammals; however,
to date, little is known about the role of liver genes in cold-induced thermogenesis in
lambs. In this study, the difference in the liver transcriptome between Altay and Hu ewe
lambs was compared. Because of different backgrounds of the two breeds, we hypothesized
that the transcriptome profiles of the liver would differ between breeds when exposed to
cold. Cold-exposed Altay lambs activated 8 candidate genes (ACTA1,
MYH1, MYH2, MYL1,
MYL2, TNNC1, TNNC2, and
TNNT3) involved in muscle shivering thermogenesis; 3 candidate genes
(ATP2A1, SLN, and CKM) involved in
muscle nonshivering thermogenesis related to the Ca2+ signal and creatine
cycle; and 6 candidate genes (PFKM, ALDOC,
PGAM2, ENO2, ENO3, and
ENO4) involved in enhancing liver metabolism. In contrast, the liver
may not act as the main tissue for thermogenesis in cold-exposed Hu lambs. We concluded
that Altay lambs rely on liver-mediated shivering and nonshivering thermogenesis by muscle
tissue to a greater extent than Hu lambs. Results from this study could provide a
theoretical foundation for the breeding and production of cold-resistant lambs.
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Mohr AE, Reiss RA, Beaudet M, Sena J, Naik JS, Walker BR, Sweazea KL. Short-term high fat diet alters genes associated with metabolic and vascular dysfunction during adolescence in rats: a pilot study. PeerJ 2021; 9:e11714. [PMID: 34285833 PMCID: PMC8274493 DOI: 10.7717/peerj.11714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 06/11/2021] [Indexed: 11/20/2022] Open
Abstract
Background Diet-induced metabolic dysfunction precedes multiple disease states including diabetes, heart disease, and vascular dysfunction. The critical role of the vasculature in disease progression is established, yet the details of how gene expression changes in early cardiovascular disease remain an enigma. The objective of the current pilot project was to evaluate whether a quantitative assessment of gene expression within the aorta of six-week old healthy male Sprague-Dawley rats compared to those exhibiting symptoms of metabolic dysfunction could reveal potential mediators of vascular dysfunction. Methods RNA was extracted from the aorta of eight rats from a larger experiment; four animals fed a high-fat diet (HFD) known to induce symptoms of metabolic dysfunction (hypertension, increased adiposity, fasting hyperglycemia) and four age-matched healthy animals fed a standard chow diet (CHOW). The bioinformatic workflow included Gene Ontology (GO) biological process enrichment and network analyses. Results The resulting network contained genes relevant to physiological processes including fat and protein metabolism, oxygen transport, hormone regulation, vascular regulation, thermoregulation, and circadian rhythm. The majority of differentially regulated genes were downregulated, including several associated with circadian clock function. In contrast, leptin and 3-hydroxy-3-methylglutaryl-CoA synthase 2 (Hmgcs2) were notably upregulated. Leptin is involved in several major energy balance signaling pathways and Hmgcs2 is a mitochondrial enzyme that catalyzes the first reaction of ketogenesis. Conclusion Together, these data describe changes in gene expression within the aortic wall of HFD rats with early metabolic dysfunction and highlight potential pathways and signaling intermediates that may impact the development of early vascular dysfunction.
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Affiliation(s)
- Alex E Mohr
- College of Health Solutions, Arizona State University, Phoenix, AZ, United States
| | - Rebecca A Reiss
- Biology Department, New Mexico Institute of Mining and Technology, Socorro, NM, United States
| | - Monique Beaudet
- Biology Department, New Mexico Institute of Mining and Technology, Socorro, NM, United States
| | - Johnny Sena
- National Center for Genome Resources, Santa Fe, NM, USA
| | - Jay S Naik
- The Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Benjimen R Walker
- The Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM, United States
| | - Karen L Sweazea
- College of Health Solutions & School of Life Sciences, Arizona State University, Tempe, AZ, USA
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Thioesterase superfamily member 1 undergoes stimulus-coupled conformational reorganization to regulate metabolism in mice. Nat Commun 2021; 12:3493. [PMID: 34108467 PMCID: PMC8190112 DOI: 10.1038/s41467-021-23595-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 04/29/2021] [Indexed: 01/21/2023] Open
Abstract
In brown adipose tissue, thermogenesis is suppressed by thioesterase superfamily member 1 (Them1), a long chain fatty acyl-CoA thioesterase. Them1 is highly upregulated by cold ambient temperature, where it reduces fatty acid availability and limits thermogenesis. Here, we show that Them1 regulates metabolism by undergoing conformational changes in response to β-adrenergic stimulation that alter Them1 intracellular distribution. Them1 forms metabolically active puncta near lipid droplets and mitochondria. Upon stimulation, Them1 is phosphorylated at the N-terminus, inhibiting puncta formation and activity and resulting in a diffuse intracellular localization. We show by correlative light and electron microscopy that Them1 puncta are biomolecular condensates that are inhibited by phosphorylation. Thus, Them1 forms intracellular biomolecular condensates that limit fatty acid oxidation and suppress thermogenesis. During a period of energy demand, the condensates are disrupted by phosphorylation to allow for maximal thermogenesis. The stimulus-coupled reorganization of Them1 provides fine-tuning of thermogenesis and energy expenditure.
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Kábelová A, Malínská H, Marková I, Oliyarnyk O, Chylíková B, Šeda O. Ellagic Acid Affects Metabolic and Transcriptomic Profiles and Attenuates Features of Metabolic Syndrome in Adult Male Rats. Nutrients 2021; 13:nu13030804. [PMID: 33671116 PMCID: PMC8001306 DOI: 10.3390/nu13030804] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 12/16/2022] Open
Abstract
Ellagic acid, a natural substance found in various fruits and nuts, was previously shown to exhibit beneficial effects towards metabolic syndrome. In this study, using a genetic rat model of metabolic syndrome, we aimed to further specify metabolic and transcriptomic responses to ellagic acid treatment. Adult male rats of the SHR-Zbtb16Lx/k.o. strain were fed a high-fat diet accompanied by daily intragastric gavage of ellagic acid (50 mg/kg body weight; high-fat diet–ellagic acid (HFD-EA) rats) or vehicle only (high-fat diet–control (HFD-CTL) rats). Morphometric and metabolic parameters, along with transcriptomic profile of liver and brown and epididymal adipose tissues, were assessed. HFD-EA rats showed higher relative weight of brown adipose tissue (BAT) and decreased weight of epididymal adipose tissue, although no change in total body weight was observed. Glucose area under the curve, serum insulin, and cholesterol levels, as well as the level of oxidative stress, were significantly lower in HFD-EA rats. The most differentially expressed transcripts reflecting the shift induced by ellagic acid were detected in BAT, showing downregulation of BAT activation markers Dio2 and Nr4a1 and upregulation of insulin-sensitizing gene Pla2g2a. Ellagic acid may provide a useful nutritional supplement to ameliorate features of metabolic syndrome, possibly by suppressing oxidative stress and its effects on brown adipose tissue.
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Affiliation(s)
- Adéla Kábelová
- Institute of Biology and Medical Genetics, The First Faculty of Medicine, Charles University and The General University Hospital, 121 08 Prague, Czech Republic; (A.K.); (B.C.)
| | - Hana Malínská
- Institute for Clinical and Experimental Medicine, 140 21 Prague, Czech Republic; (H.M.); (I.M.); (O.O.)
| | - Irena Marková
- Institute for Clinical and Experimental Medicine, 140 21 Prague, Czech Republic; (H.M.); (I.M.); (O.O.)
| | - Olena Oliyarnyk
- Institute for Clinical and Experimental Medicine, 140 21 Prague, Czech Republic; (H.M.); (I.M.); (O.O.)
| | - Blanka Chylíková
- Institute of Biology and Medical Genetics, The First Faculty of Medicine, Charles University and The General University Hospital, 121 08 Prague, Czech Republic; (A.K.); (B.C.)
| | - Ondřej Šeda
- Institute of Biology and Medical Genetics, The First Faculty of Medicine, Charles University and The General University Hospital, 121 08 Prague, Czech Republic; (A.K.); (B.C.)
- Correspondence: ; Tel.: +420-224-968-180
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Tan Y, Gan M, Shen L, Li L, Fan Y, Chen Y, Chen L, Niu L, Zhao Y, Jiang A, Jiang D, Zhang S, Zhu L. Profiling and Functional Analysis of Long Noncoding RNAs and mRNAs during Porcine Skeletal Muscle Development. Int J Mol Sci 2021; 22:ijms22020503. [PMID: 33419093 PMCID: PMC7825455 DOI: 10.3390/ijms22020503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/28/2020] [Accepted: 01/01/2021] [Indexed: 11/16/2022] Open
Abstract
Gene transcripts or mRNAs and long noncoding RNAs (lncRNAs) are differentially expressed during porcine skeletal muscle development. However, only a few studies have been conducted on skeletal muscle transcriptome in pigs based on timepoints according to the growth curve for porcine. Here, we investigated gene expression in Qingyu pigs at three different growth stages: the inflection point with the maximum growth rate (MGI), the inflection point of the gradually increasing stage to the rapidly increasing stage (GRI), and the inflection point of the rapidly increasing stage to the slowly increasing stage (RSI). Subsequently, we explored gene expression profiles during muscle development at the MGI, GRI and RSI stages by Ribo-Zero RNA sequencing. Qingyu pigs reached the MGI, GRI and RSI stages at 156.40, 23.82 and 288.97 days of age with 51.73, 3.14 and 107.03 kg body weight, respectively. A total of 14,530 mRNAs and 11,970 lncRNAs were identified at the three stages, and 645, 323 differentially expressed genes (DEGs) and 696, 760 differentially expressed lncRNAs (DELs) were identified in the GRI vs. MGI, and RSI vs. MGI, comparisons. Functional enrichment analysis revealed that genes involved in immune system development and energy metabolism (mainly relate to amino acid, carbohydrate and lipid) were enriched at the GRI and MGI stages, respectively, whereas genes involved in lipid metabolism were enriched at the RSI stage. We further characterized G1430, an abundant lncRNA. The full-length sequence (316 nt) of lncRNA G1430 was determined by rapid amplification of cDNA ends (RACE). Subcellular distribution analysis by quantitative real-time PCR (qRT-PCR) revealed that G1430 is a cytoplasmic lncRNA. Binding site prediction and dual luciferase assay showed that lncRNA G1430 directly binds to microRNA 133a (miR-133a). Our findings provide the basis for further investigation of the regulatory mechanisms and molecular genetics of muscle development in pigs.
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Affiliation(s)
- Ya Tan
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
- Institute of Animal Husbandry and Veterinary, Guizhou Academy of Agricultural Science, Guiyang 550005, China
| | - Mailin Gan
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Linyuan Shen
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Liang Li
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
- Institute of Animal Husbandry and Veterinary, Guizhou Academy of Agricultural Science, Guiyang 550005, China
| | - Yuan Fan
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Ying Chen
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Lei Chen
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Lili Niu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Ye Zhao
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Anan Jiang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Dongmei Jiang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
| | - Shunhua Zhang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
- Correspondence: (S.Z.); (L.Z.); Tel.: +86-28-8629-1133 (S.Z. & L.Z.)
| | - Li Zhu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China; (Y.T.); (M.G.); (L.S.); (L.L.); (Y.F.); (Y.C.); (L.C.); (L.N.); (Y.Z.); (A.J.); (D.J.)
- Correspondence: (S.Z.); (L.Z.); Tel.: +86-28-8629-1133 (S.Z. & L.Z.)
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Xu CL, Chen L, Li D, Chen FT, Sha ML, Shao Y. Acyl-CoA Thioesterase 8 and 11 as Novel Biomarkers for Clear Cell Renal Cell Carcinoma. Front Genet 2020; 11:594969. [PMID: 33362855 PMCID: PMC7758486 DOI: 10.3389/fgene.2020.594969] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/18/2020] [Indexed: 01/21/2023] Open
Abstract
Background Clear cell renal cell carcinoma (ccRCC) is essentially a metabolic disorder characterized by reprogramming of several metabolic pathways. Acyl-coenzyme A thioesterases (ACOTs) are critical enzymes involved in fatty acid metabolism; however, the roles of ACOTs in ccRCC remain unclear. This study explored ACOTs expressions and their diagnostic and prognostic values in ccRCC. Methods Three online ccRCC datasets from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) were utilized to measure the expressions of ACOTs in paired normal and tumor tissues. Receiver operating characteristic (ROC) curves were depicted to assess the diagnostic values of ACOTs in ccRCC. Quantitative real-time PCR and immunohistochemical analysis were performed to validate the ACOT11 expression in ccRCC cell lines and clinical samples. Survival curves and Cox regression analysis were used to evaluate the predictive values of ACOTs in clinical outcome of ccRCC patients. Functional enrichment analyses and correlation analysis were carried out to predict the potential roles of ACOT8 in tumorigenesis and progression of ccRCC. Results ACOT1/2/8/11/13 were found to be significantly downregulated in ccRCC samples. In particular, ACOT11 was decreased in almost every matched normal-tumor pair, and had extremely high diagnostic value as shown by ROC curve analysis (AUC = 0.964). The expression of ACOT11 was further verified in ccRCC cell lines and clinical samples at mRNA and protein levels. Furthermore, clinical correlation analysis and survival analysis indicated that ACOT8 was correlated with disease progression and was an independent predictor of unfavorable outcome in ccRCC. Moreover, functional analyses suggested potential roles of ACOT8 in the regulation of oxidative phosphorylation (OXPHOS), and correlation analysis revealed an association between ACOT8 and ferroptosis-related genes in ccRCC. Conclusion Our study revealed that ACOT11 and ACOT8 are promising biomarkers for diagnosis and prognosis of ccRCC, respectively, and ACOT8 may affect ccRCC development and progression through the regulation of OXPHOS and ferroptosis. These findings may provide new strategies for precise diagnosis and personalized therapy of ccRCC.
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Affiliation(s)
- Chao-Liang Xu
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lei Chen
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Deng Li
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fei-Teng Chen
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ming-Lei Sha
- Department of Geriatric, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi Shao
- Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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15
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Pei Y, Otieno D, Gu I, Lee SO, Parks JS, Schimmel K, Kang HW. Effect of quercetin on nonshivering thermogenesis of brown adipose tissue in high-fat diet-induced obese mice. J Nutr Biochem 2020; 88:108532. [PMID: 33130188 DOI: 10.1016/j.jnutbio.2020.108532] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 06/18/2020] [Accepted: 10/20/2020] [Indexed: 12/18/2022]
Abstract
Activating nonshivering thermogenesis in brown adipose tissue (BAT) is a promising strategy to prevent obesity. This study investigated whether quercetin supplementation improves obesity in mice by increasing nonshivering thermogenesis in BAT and white adipose tissue (WAT) browning. Compared to high-fat diet (HFD)-fed mice, mice fed a HFD supplemented with 1% quercetin (HFDQ) had reduced body weight and total plasma cholesterol. In HFDQ-fed mice, retroperitoneal WAT (RWAT) weight was decreased, and browning effect and lipolysis were increased. HFDQ-fed mice had increased expression of nonshivering thermogenesis genes in BAT, including uncoupling protein 1 (UCP1), peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC1α), cell death-inducing DFFA-like effector A (CIDEA), and mitochondrial transcriptional factor A (mtTFA). Quercetin supplementation increased genes and proteins in β3-adrenergic receptor (ADRB3), p38 mitogen-activated protein kinase (MAPK), and AMP-activated protein kinase (AMPK) pathways in HFD-fed mice, which were suppressed by an AMPK inhibitor or an ADRB3 antagonist. Energy expenditure and core body temperature were not changed by quercetin, but physical activity was increased in HFDQ mice during dark periods at room and cold temperatures. Quercetin also decreased the Firmicutes to Bacteroidetes ratio and increased short-chain fatty acid production in the feces of HFD-fed mice. In summary, quercetin supplementation in HFD-fed mice may attenuate obesity. Although the study did not show consistency in data at molecular and pathophysiological levels between BAT function and obesity, it also shows promising health effects of quercetin, accompanied by improved physical activity and gut microbiota dysbiosis.
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Affiliation(s)
- Ya Pei
- Food and Nutritional Sciences, Department of Family and Consumer Sciences, North Carolina Agricultural and Technical State University, Greensboro, North Carolina, USA
| | - Dammah Otieno
- Applied Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, North Carolina, USA
| | - Inah Gu
- Department of Food Science, University of Arkansas, Fayetteville, Arkansas, USA
| | - Sun-Ok Lee
- Department of Food Science, University of Arkansas, Fayetteville, Arkansas, USA
| | - John S Parks
- Department of Internal Medicine-Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Keith Schimmel
- Applied Science and Technology, North Carolina Agricultural and Technical State University, Greensboro, North Carolina, USA
| | - Hye Won Kang
- Food and Nutritional Sciences, Department of Family and Consumer Sciences, North Carolina Agricultural and Technical State University, Greensboro, North Carolina, USA.
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16
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Tillman MC, Imai N, Li Y, Khadka M, Okafor CD, Juneja P, Adhiyaman A, Hagen SJ, Cohen DE, Ortlund EA. Allosteric regulation of thioesterase superfamily member 1 by lipid sensor domain binding fatty acids and lysophosphatidylcholine. Proc Natl Acad Sci U S A 2020; 117:22080-22089. [PMID: 32820071 PMCID: PMC7486800 DOI: 10.1073/pnas.2003877117] [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] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Nonshivering thermogenesis occurs in brown adipose tissue to generate heat in response to cold ambient temperatures. Thioesterase superfamily member 1 (Them1) is transcriptionally up-regulated in brown adipose tissue upon exposure to the cold and suppresses thermogenesis in order to conserve energy reserves. It hydrolyzes long-chain fatty acyl-CoAs that are derived from lipid droplets, preventing their use as fuel for thermogenesis. In addition to its enzymatic domains, Them1 contains a C-terminal StAR-related lipid transfer (START) domain with unknown ligand or function. By complementary biophysical approaches, we show that the START domain binds to long-chain fatty acids, products of Them1's enzymatic reaction, as well as lysophosphatidylcholine (LPC), lipids shown to activate thermogenesis in brown adipocytes. Certain fatty acids stabilize the START domain and allosterically enhance Them1 catalysis of acyl-CoA, whereas 18:1 LPC destabilizes and inhibits activity, which we verify in cell culture. Additionally, we demonstrate that the START domain functions to localize Them1 near lipid droplets. These findings define the role of the START domain as a lipid sensor that allosterically regulates Them1 activity and spatially localizes it in proximity to the lipid droplet.
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Affiliation(s)
- Matthew C Tillman
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Norihiro Imai
- Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065
| | - Yue Li
- Department of Surgery, Beth Israel Deaconess Medical Center, Boston, MA 02215
| | - Manoj Khadka
- Emory Integrated Lipidomics Core, Emory University, Atlanta, GA 30322
| | - C Denise Okafor
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Puneet Juneja
- Robert P. Apkarian Integrated Electron Microscopy Core, Emory University, Atlanta, GA 30322
| | - Akshitha Adhiyaman
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Susan J Hagen
- Department of Surgery, Beth Israel Deaconess Medical Center, Boston, MA 02215
| | - David E Cohen
- Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10065
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322;
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17
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Clark BJ. The START-domain proteins in intracellular lipid transport and beyond. Mol Cell Endocrinol 2020; 504:110704. [PMID: 31927098 DOI: 10.1016/j.mce.2020.110704] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 01/08/2020] [Accepted: 01/08/2020] [Indexed: 12/17/2022]
Abstract
The Steroidogenic Acute Regulatory Protein-related Lipid Transfer (START) domain is a ~210 amino acid sequence that folds into an α/β helix-grip structure forming a hydrophobic pocket for lipid binding. The helix-grip fold structure defines a large superfamily of proteins, and this review focuses on the mammalian START domain family members that include single START domain proteins with identified ligands, and larger multi-domain proteins that may have novel roles in metabolism. Much of our understanding of the mammalian START domain proteins in lipid transport and changes in metabolism has advanced through studies using knockout mouse models, although for some of these proteins the identity and/or physiological role of ligand binding remains unknown. The findings that helped define START domain lipid-binding specificity, lipid transport, and changes in metabolism are presented to highlight that fundamental questions remain regarding the biological function(s) for START domain-containing proteins.
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Affiliation(s)
- Barbara J Clark
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA.
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18
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Krisko TI, Nicholls HT, Bare CJ, Holman CD, Putzel GG, Jansen RS, Sun N, Rhee KY, Banks AS, Cohen DE. Dissociation of Adaptive Thermogenesis from Glucose Homeostasis in Microbiome-Deficient Mice. Cell Metab 2020; 31:592-604.e9. [PMID: 32084379 PMCID: PMC7888548 DOI: 10.1016/j.cmet.2020.01.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 11/18/2019] [Accepted: 01/24/2020] [Indexed: 01/16/2023]
Abstract
Recent studies suggest that a key mechanism whereby the gut microbiome influences energy balance and glucose homeostasis is through the recruitment of brown and beige adipocytes, primary mediators of the adaptive thermogenic response. To test this, we assessed energy expenditure and glucose metabolism in two complementary mouse models of gut microbial deficiency, which were exposed to a broad range of thermal and dietary stresses. Neither ablation of the gut microbiome, nor the substantial microbial perturbations induced by cold ambient temperatures, influenced energy expenditure during cold exposure or high-fat feeding. Nevertheless, we demonstrated a critical role for gut microbial metabolism in maintaining euglycemia through the production of amino acid metabolites that optimized hepatic TCA (tricarboxylic acid) cycle fluxes in support of gluconeogenesis. These results distinguish the dispensability of the gut microbiome for the regulation of energy expenditure from its critical contribution to the maintenance of glucose homeostasis.
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Affiliation(s)
- Tibor I Krisko
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Hayley T Nicholls
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Curtis J Bare
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Corey D Holman
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Gregory G Putzel
- Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medical College, New York, NY 10021, USA
| | - Robert S Jansen
- Division of Infectious Diseases, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Natalie Sun
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Kyu Y Rhee
- Division of Infectious Diseases, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA
| | - Alexander S Banks
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
| | - David E Cohen
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA.
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SUMOylation inhibitors synergize with FXR agonists in combating liver fibrosis. Nat Commun 2020; 11:240. [PMID: 31932588 PMCID: PMC6957516 DOI: 10.1038/s41467-019-14138-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 12/19/2019] [Indexed: 02/06/2023] Open
Abstract
Farnesoid X receptor (FXR) is a promising target for nonalcoholic steatohepatitis (NASH) and fibrosis. Although various FXR agonists have shown anti-fibrotic effects in diverse preclinical animal models, the response rate and efficacies in clinical trials were not optimum. Here we report that prophylactic but not therapeutic administration of obeticholic acid (OCA) prevents hepatic stellate cell (HSC) activation and fibrogenesis. Activated HSCs show limited response to OCA and other FXR agonists due to enhanced FXR SUMOylation. SUMOylation inhibitors rescue FXR signaling and thereby increasing the efficacy of OCA against HSC activation and fibrosis. FXR upregulates Perilipin-1, a direct target gene of FXR, to stabilize lipid droplets and thereby prevent HSC activation. Therapeutic coadministration of OCA and SUMOylation inhibitors drastically impedes liver fibrosis induced by CCl4, bile duct ligation, and more importantly NASH. In conclusion, we propose a promising therapeutic approach by combining SUMOylation inhibitors and FXR agonists for liver fibrosis. FXR agonists have been investigated for the treatment of non-alcoholic steatohepatitis and liver fibrosis but the clinical efficacy is not optimal. Here the authors show that enhanced FXR SUMOylation in activated hepatic stellate cells reduces FXR signaling and that this can be rescued by SUMOylation inhibitors.
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20
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Gapp B, Jourdain M, Bringer P, Kueng B, Weber D, Osmont A, Zurbruegg S, Knehr J, Falchetto R, Roma G, Dietrich W, Valdez R, Beckmann N, Nigsch F, Sanyal AJ, Ksiazek I. Farnesoid X Receptor Agonism, Acetyl-Coenzyme A Carboxylase Inhibition, and Back Translation of Clinically Observed Endpoints of De Novo Lipogenesis in a Murine NASH Model. Hepatol Commun 2019; 4:109-125. [PMID: 31909359 PMCID: PMC6939503 DOI: 10.1002/hep4.1443] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/03/2019] [Indexed: 12/16/2022] Open
Abstract
A promising approach for the treatment of nonalcoholic steatohepatitis (NASH) is the inhibition of enhanced hepatic de novo lipogenesis (DNL), which is the synthesis of fatty acids from nonlipid sources. This study assesses three approaches to DNL suppression in a newly developed dietary NASH mouse model: i) dietary intervention (switch from NASH‐inducing diet to normal diet); ii) inhibition of acetyl‐coenzyme A carboxylase (ACC), the enzyme catalyzing the rate‐limiting step in DNL; and iii) activation of farnesoid X receptor (FXR), a major transcriptional regulator of DNL. C57BL/6J mice on a high‐fat diet combined with ad libitum consumption of a fructose–sucrose solution developed several of the liver histologic features seen in human disease, including steatosis, inflammation, and fibrosis, accompanied by elevated fibrosis biomarkers and liver injury enzymes. Obesity and metabolic impairments were associated with increased intestinal permeability and progression to adenoma and hepatocellular carcinoma. All three approaches led to resolution of established NASH with fibrosis in mice; however, some differences were noted, e.g., with respect to the degree of hepatic steatosis attenuation. While ACC inhibition resulted in elevated blood triglycerides and peripheral obesity, FXR activation prevented peripheral obesity in NASH mice. Comparative transcriptome analysis underlined the translatability of the mouse model to human NASH and revealed novel mechanistic insights into differential regulation of lipid, inflammatory, and extracellular matrix pathways by FXR agonism and ACC inhibition. Conclusion: Novel insights are provided on back translation of clinically observed endpoints of DNL inhibition by targeting ACC or FXR, which are promising therapeutic options for the treatment of NASH, in a newly developed diet‐induced NASH mouse model.
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Affiliation(s)
- Berangere Gapp
- Disease Area X Novartis Institutes for BioMedical Research Basel Switzerland
| | - Marie Jourdain
- Disease Area X Novartis Institutes for BioMedical Research Basel Switzerland
| | - Pauline Bringer
- Disease Area X Novartis Institutes for BioMedical Research Basel Switzerland
| | - Benjamin Kueng
- Disease Area X Novartis Institutes for BioMedical Research Basel Switzerland
| | - Delphine Weber
- Disease Area X Novartis Institutes for BioMedical Research Basel Switzerland
| | - Arnaud Osmont
- Biotherapeutic and Analytical Technologies Novartis Institutes for BioMedical Research Basel Switzerland
| | - Stefan Zurbruegg
- Neurosciences Novartis Institutes for BioMedical Research Basel Switzerland
| | - Judith Knehr
- Chemical Biology and Therapeutics Novartis Institutes for BioMedical Research Basel Switzerland
| | - Rocco Falchetto
- Biotherapeutic and Analytical Technologies Novartis Institutes for BioMedical Research Basel Switzerland
| | - Guglielmo Roma
- Chemical Biology and Therapeutics Novartis Institutes for BioMedical Research Basel Switzerland
| | - William Dietrich
- Disease Area X Novartis Institutes for BioMedical Research Cambridge MA
| | - Reginald Valdez
- Disease Area X Novartis Institutes for BioMedical Research Cambridge MA
| | - Nicolau Beckmann
- Musculoskeletal Diseases Novartis Institutes for BioMedical Research Basel Switzerland
| | - Florian Nigsch
- Chemical Biology and Therapeutics Novartis Institutes for BioMedical Research Basel Switzerland
| | - Arun J Sanyal
- Department of Internal Medicine Division of Gastroenterology Virginia Commonwealth University Richmond VA
| | - Iwona Ksiazek
- Disease Area X Novartis Institutes for BioMedical Research Basel Switzerland
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21
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BCL6 regulates brown adipocyte dormancy to maintain thermogenic reserve and fitness. Proc Natl Acad Sci U S A 2019; 116:17071-17080. [PMID: 31375635 PMCID: PMC6708354 DOI: 10.1073/pnas.1907308116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
During exposure to environmental cold, brown adipocytes protect against hypothermia by generating heat (thermogenesis). In warm environments, brown adipocytes become inactive or dormant but still maintain their identity and thermogenic capacity, allowing rapid reactivation of thermogenesis upon subsequent cold exposure. Our understanding of the dormant state and its regulation is very limited. Here, we show that the transcription factor B cell leukemia/lymphoma 6 (BCL6) is specifically required for maintenance of thermogenic capacity during dormancy in brown adipocytes. Mechanistically, BCL6 drives a gene expression program that promotes survival, fatty acid oxidation, and uncoupled respiration. Thus, unlike other transcription factors that regulate cold-induced thermogenesis, BCL6 is specifically required for maintaining thermogenic fitness during adaptation to environmental warmth. Brown adipocytes provide a metabolic defense against environmental cold but become dormant as mammals habituate to warm environments. Although dormancy is a regulated response in brown adipocytes to environmental warmth, its transcriptional mechanisms and functional importance are unknown. Here, we identify B cell leukemia/lymphoma 6 (BCL6) as a critical regulator of dormancy in brown adipocytes but not for their commitment, differentiation, or cold-induced activation. In a temperature-dependent manner, BCL6 suppresses apoptosis, fatty acid storage, and coupled respiration to maintain thermogenic fitness during dormancy. Mechanistically, BCL6 remodels the epigenome of brown adipocytes to enforce brown and oppose white adipocyte cellular identity. Thus, unlike other thermogenic regulators, BCL6 is specifically required for maintaining thermogenic fitness when mammals acclimate to environmental warmth.
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22
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Tardo-Dino PE, Touron J, Baugé S, Bourdon S, Koulmann N, Malgoyre A. The effect of a physiological increase in temperature on mitochondrial fatty acid oxidation in rat myofibers. J Appl Physiol (1985) 2019; 127:312-319. [PMID: 31161881 DOI: 10.1152/japplphysiol.00652.2018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We investigated the effect of temperature increase on mitochondrial fatty acid (FA) and carbohydrate oxidation in the slow-oxidative skeletal muscles (soleus) of rats. We measured mitochondrial respiration at 35°C and 40°C with the physiological substrates pyruvate + 4 mM malate (Pyr) and palmitoyl-CoA (PCoA) + 0.5 mM malate + 2 mM carnitine in permeabilized myofibers under nonphosphorylating (V˙0) or phosphorylating (V˙max) conditions. Mitochondrial efficiency was calculated by the respiratory control ratio (RCR = V˙max/V˙0). We used guanosine triphosphate (GTP), an inhibitor of uncoupling protein (UCP), to study the mechanisms responsible for alterations of mitochondrial efficiency. We measured hydrogen peroxide (H2O2) production under nonphosphorylating and phosphorylating conditions at both temperatures and substrates. We studied citrate synthase (CS) and 3-hydroxyl acyl coenzyme A dehydrogenase (3-HAD) activities at both temperatures. Elevating the temperature from 35°C to 40°C increased PCoA-V˙0 and decreased PCoA-RCR, corresponding to the uncoupling of oxidative phosphorylation (OXPHOS). GTP blocked the heat-induced increase of PCoA-V˙0. Rising temperature moved toward a Pyr-V˙0 increase, without significance. Heat did not alter H2O2 production, resulting from either PCoA or Pyr oxidation. Heat induced an increase in 3-HAD but not in CS activities. In conclusion, heat induced OXPHOS uncoupling for PCoA oxidation, which was at least partially mediated by UCP and independent of oxidative stress. The classically described heat-induced glucose shift may actually be mostly due to a less efficient FA oxidation. These findings raise questions concerning the consequences of heat-induced alterations in mitochondrial efficiency of FA metabolism on thermoregulation.NEW & NOTEWORTHY Ex vivo exposure of skeletal myofibers to heat uncouples substrate oxidation from ADP phosphorylation, decreasing the efficiency of mitochondria to produce ATP. This heat effect alters fatty acids (FAs) more than carbohydrate oxidation. Alteration of FA oxidation involves uncoupling proteins without inducing oxidative stress. This alteration in lipid metabolism may underlie the preferential use of carbohydrates in the heat and could decrease aerobic endurance.
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Affiliation(s)
- Pierre-Emmanuel Tardo-Dino
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,Ecole du Val-de-Grâce, Paris, France.,EDISS 205, Université Claude Bernard Lyon 1, Villeurbanne, France
| | - Julianne Touron
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France
| | - Stéphane Baugé
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France
| | - Stéphanie Bourdon
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France
| | - Nathalie Koulmann
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France.,Ecole du Val-de-Grâce, Paris, France.,EDISS 205, Université Claude Bernard Lyon 1, Villeurbanne, France
| | - Alexandra Malgoyre
- Unité de Physiologie de l'Exercice et des Activités en Conditions Extrêmes, Département Environnements Opérationnels, Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France
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23
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Peres Valgas da Silva C, Hernández-Saavedra D, White JD, Stanford KI. Cold and Exercise: Therapeutic Tools to Activate Brown Adipose Tissue and Combat Obesity. BIOLOGY 2019; 8:biology8010009. [PMID: 30759802 PMCID: PMC6466122 DOI: 10.3390/biology8010009] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 12/11/2022]
Abstract
The rise in obesity over the last several decades has reached pandemic proportions. Brown adipose tissue (BAT) is a thermogenic organ that is involved in energy expenditure and represents an attractive target to combat both obesity and type 2 diabetes. Cold exposure and exercise training are two stimuli that have been investigated with respect to BAT activation, metabolism, and the contribution of BAT to metabolic health. These two stimuli are of great interest because they have both disparate and converging effects on BAT activation and metabolism. Cold exposure is an effective mechanism to stimulate BAT activity and increase glucose and lipid uptake through mitochondrial uncoupling, resulting in metabolic benefits including elevated energy expenditure and increased insulin sensitivity. Exercise is a therapeutic tool that has marked benefits on systemic metabolism and affects several tissues, including BAT. Compared to cold exposure, studies focused on BAT metabolism and exercise display conflicting results; the majority of studies in rodents and humans demonstrate a reduction in BAT activity and reduced glucose and lipid uptake and storage. In addition to investigations of energy uptake and utilization, recent studies have focused on the effects of cold exposure and exercise on the structural lipids in BAT and secreted factors released from BAT, termed batokines. Cold exposure and exercise induce opposite responses in terms of structural lipids, but an important overlap exists between the effects of cold and exercise on batokines. In this review, we will discuss the similarities and differences of cold exposure and exercise in relation to their effects on BAT activity and metabolism and its relevance for the prevention of obesity and the development of type 2 diabetes.
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Affiliation(s)
- Carmem Peres Valgas da Silva
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
| | - Diego Hernández-Saavedra
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
| | - Joseph D White
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
| | - Kristin I Stanford
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
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24
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Tillander V, Miniami A, Alves-Bezerra M, Coleman RA, Cohen DE. Thioesterase superfamily member 2 promotes hepatic insulin resistance in the setting of glycerol-3-phosphate acyltransferase 1-induced steatosis. J Biol Chem 2018; 294:2009-2020. [PMID: 30523156 DOI: 10.1074/jbc.ra118.005184] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 11/21/2018] [Indexed: 02/05/2023] Open
Abstract
Hepatic insulin resistance in the setting of steatosis is attributable at least in part to the accumulation of bioactive lipids that suppress insulin signaling. The mitochondria-associated glycerol-3-phosphate acyltransferase 1 (GPAT1) catalyzes the first committed step in glycerolipid synthesis, and its activity diverts fatty acids from mitochondrial β-oxidation. GPAT1 overexpression in mouse liver leads to hepatic steatosis even in the absence of overnutrition. The mice develop insulin resistance owing to the generation of saturated diacylglycerol and phosphatidic acid molecular species that reduce insulin signaling by activating PKCϵ and by suppressing mTORC2, respectively. Them2, a mitochondria-associated acyl-CoA thioesterase, also participates in the trafficking of fatty acids into oxidative versus glycerolipid biosynthetic pathways. Them2 -/- mice are protected against diet-induced hepatic steatosis and insulin resistance. To determine whether Them2 contributes to hepatic insulin resistance due to hepatic overexpression of GPAT1, recombinant adenovirus was used to overexpress GPAT1 in livers of chow-fed Them2 +/+ and Them2 -/- mice. Hepatic GPAT1 overexpression led to steatosis in both genotypes. In the setting of GPAT1 overexpression, glucose tolerance was reduced in Them2 +/+ but not Them2 -/- mice, without influencing whole-body insulin sensitivity or basal hepatic glucose production. Improved glucose tolerance in Them2 -/- mice was associated with reduced PKCϵ translocation. Preserved insulin receptor activity was supported by Thr-308 phosphorylation of Akt following GPAT1 overexpression in Them2 -/- hepatocytes. These findings suggest a pathogenic role of Them2 in the biosynthesis of glycerolipid metabolites that promote hepatic insulin resistance.
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Affiliation(s)
- Veronika Tillander
- From the Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, New York 10021.,the Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institute, 14152 Huddinge, Sweden
| | - Akihiro Miniami
- From the Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, New York 10021.,the Department of Gastroenterology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan, and
| | - Michele Alves-Bezerra
- From the Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, New York 10021
| | - Rosalind A Coleman
- the Department of Nutrition, University of North Carolina, Chapel Hill, North Carolina 27599
| | - David E Cohen
- From the Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, New York 10021,
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25
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Li J, Deng SP, Wei G, Yu P. CITGeneDB: a comprehensive database of human and mouse genes enhancing or suppressing cold-induced thermogenesis validated by perturbation experiments in mice. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2018; 2018:4953403. [PMID: 29688375 PMCID: PMC5868181 DOI: 10.1093/database/bay012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/18/2018] [Indexed: 11/14/2022]
Abstract
Abstract Cold-induced thermogenesis increases energy expenditure and can reduce body weight in mammals, so the genes involved in it are thought to be potential therapeutic targets for treating obesity and diabetes. In the quest for more effective therapies, a great deal of research has been conducted to elucidate the regulatory mechanism of cold-induced thermogenesis. Over the last decade, a large number of genes that can enhance or suppress cold-induced thermogenesis have been discovered, but a comprehensive list of these genes is lacking. To fill this gap, we examined all of the annotated human and mouse genes and curated those demonstrated to enhance or suppress cold-induced thermogenesis by in vivo or ex vivo experiments in mice. The results of this highly accurate and comprehensive annotation are hosted on a database called CITGeneDB, which includes a searchable web interface to facilitate broad public use. The database will be updated as new genes are found to enhance or suppress cold-induced thermogenesis. It is expected that CITGeneDB will be a valuable resource in future explorations of the molecular mechanism of cold-induced thermogenesis, helping pave the way for new obesity and diabetes treatments.
Database URL: http://citgenedb.yubiolab.org.
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Affiliation(s)
- Jin Li
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA.,TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Su-Ping Deng
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA.,TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Gang Wei
- Shanghai Key Laboratory of Diabetes, Shanghai Institute for Diabetes, Shanghai Clinical Medical Centre of Diabetes, Shanghai Key Clinical Centre of Metabolic Diseases, Department of Endocrinology and Metabolism, Shanghai Jiao-Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Peng Yu
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843, USA.,TEES-AgriLife Center for Bioinformatics and Genomic Systems Engineering, Texas A&M University, College Station, TX 77843, USA
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26
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Hankir MK, Klingenspor M. Brown adipocyte glucose metabolism: a heated subject. EMBO Rep 2018; 19:embr.201846404. [PMID: 30135070 DOI: 10.15252/embr.201846404] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/22/2018] [Accepted: 07/20/2018] [Indexed: 11/09/2022] Open
Abstract
The energy expending and glucose sink properties of brown adipose tissue (BAT) make it an attractive target for new obesity and diabetes treatments. Despite decades of research, only recently have mechanistic studies started to provide a more complete and consistent picture of how activated brown adipocytes handle glucose. Here, we discuss the importance of intracellular glycolysis, lactate production, lipogenesis, lipolysis, and beta-oxidation for BAT thermogenesis in response to natural (temperature) and artificial (pharmacological and optogenetic) forms of sympathetic nervous system stimulation. It is now clear that together, these metabolic processes in series and in parallel flexibly power ATP-dependent and independent futile cycles in brown adipocytes to impact on whole-body thermal, energy, and glucose balance.
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Affiliation(s)
- Mohammed K Hankir
- Department of Experimental Surgery, University Hospital Wuerzburg, Wuerzburg, Germany .,German Research Foundation Collaborative Research Center in Obesity Mechanisms 1052, University of Leipzig, Leipzig, Germany
| | - Martin Klingenspor
- Chair of Molecular Nutritional Medicine, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany .,EKFZ - Else Kröner-Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany
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27
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Steensels S, Ersoy BA. Fatty acid activation in thermogenic adipose tissue. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:79-90. [PMID: 29793055 DOI: 10.1016/j.bbalip.2018.05.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 03/10/2018] [Accepted: 05/17/2018] [Indexed: 02/07/2023]
Abstract
Channeling carbohydrates and fatty acids to thermogenic tissues, including brown and beige adipocytes, have garnered interest as an approach for the management of obesity-related metabolic disorders. Mitochondrial fatty acid oxidation (β-oxidation) is crucial for the maintenance of thermogenesis. Upon cellular fatty acid uptake or following lipolysis from triglycerides (TG), fatty acids are esterified to coenzyme A (CoA) to form active acyl-CoA molecules. This enzymatic reaction is essential for their utilization in β-oxidation and thermogenesis. The activation and deactivation of fatty acids are regulated by two sets of enzymes called acyl-CoA synthetases (ACS) and acyl-CoA thioesterases (ACOT), respectively. The expression levels of ACS and ACOT family members in thermogenic tissues will determine the substrate availability for β-oxidation, and consequently the thermogenic capacity. Although the role of the majority of ACS and ACOT family members in thermogenesis remains unclear, recent proceedings link the enzymatic activities of ACS and ACOT family members to metabolic disorders and thermogenesis. Elucidating the contributions of specific ACS and ACOT family members to trafficking of fatty acids towards thermogenesis may reveal novel targets for modulating thermogenic capacity and treating metabolic disorders.
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Affiliation(s)
- Sandra Steensels
- Department of Medicine, Division of Gastroenterology and Hepatology, Weill Cornell Medical College, New York, NY, USA
| | - Baran A Ersoy
- Department of Medicine, Division of Gastroenterology and Hepatology, Weill Cornell Medical College, New York, NY, USA.
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28
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Kohlgruber AC, Gal-Oz ST, LaMarche NM, Shimazaki M, Duquette D, Koay HF, Nguyen HN, Mina AI, Paras T, Tavakkoli A, von Andrian U, Uldrich AP, Godfrey DI, Banks AS, Shay T, Brenner MB, Lynch L. γδ T cells producing interleukin-17A regulate adipose regulatory T cell homeostasis and thermogenesis. Nat Immunol 2018; 19:464-474. [PMID: 29670241 DOI: 10.1038/s41590-018-0094-2] [Citation(s) in RCA: 210] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 03/16/2018] [Indexed: 01/10/2023]
Abstract
γδ T cells are situated at barrier sites and guard the body from infection and damage. However, little is known about their roles outside of host defense in nonbarrier tissues. Here, we characterize a highly enriched tissue-resident population of γδ T cells in adipose tissue that regulate age-dependent regulatory T cell (Treg) expansion and control core body temperature in response to environmental fluctuations. Mechanistically, innate PLZF+ γδ T cells produced tumor necrosis factor and interleukin (IL) 17 A and determined PDGFRα+ and Pdpn+ stromal-cell production of IL-33 in adipose tissue. Mice lacking γδ T cells or IL-17A exhibited decreases in both ST2+ Treg cells and IL-33 abundance in visceral adipose tissue. Remarkably, these mice also lacked the ability to regulate core body temperature at thermoneutrality and after cold challenge. Together, these findings uncover important physiological roles for resident γδ T cells in adipose tissue immune homeostasis and body-temperature control.
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Affiliation(s)
- Ayano C Kohlgruber
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA.,Division of Medical Sciences, Harvard Medical School, Boston, MA, USA
| | - Shani T Gal-Oz
- Department of Life Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Nelson M LaMarche
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA.,Division of Medical Sciences, Harvard Medical School, Boston, MA, USA
| | - Moto Shimazaki
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA
| | - Danielle Duquette
- Division of Endocrinology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Hui-Fern Koay
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia.,ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - Hung N Nguyen
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA
| | - Amir I Mina
- Division of Endocrinology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Tyler Paras
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA
| | - Ali Tavakkoli
- Department of General and Gastrointestinal Surgery, Brigham and Women's Hospital, Boston, MA, USA
| | - Ulrich von Andrian
- Division of Medical Sciences, Harvard Medical School, Boston, MA, USA.,Department of Microbiology and Immunology, Harvard Medical School, Boston, MA, USA
| | - Adam P Uldrich
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia.,ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - Dale I Godfrey
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, Australia.,ARC Centre of Excellence in Advanced Molecular Imaging, University of Melbourne, Parkville, Australia
| | - Alexander S Banks
- Division of Endocrinology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Tal Shay
- Department of Life Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Michael B Brenner
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA.
| | - Lydia Lynch
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA. .,Division of Endocrinology, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA. .,School of Biochemistry and Immunology, Trinity College, Dublin, Ireland.
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29
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Desai A, Alves-Bezerra M, Li Y, Ozdemir C, Bare CJ, Li Y, Hagen SJ, Cohen DE. Regulation of fatty acid trafficking in liver by thioesterase superfamily member 1. J Lipid Res 2018; 59:368-379. [PMID: 29208699 PMCID: PMC5794430 DOI: 10.1194/jlr.m081455] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/04/2017] [Indexed: 12/13/2022] Open
Abstract
Thioesterase superfamily member 1 (Them1) is an acyl-CoA thioesterase that is highly expressed in brown adipose tissue, where it functions to suppress energy expenditure. Lower Them1 expression levels in the liver are upregulated in response to high-fat feeding. Them1-/- mice are resistant to diet-induced obesity, hepatic steatosis, and glucose intolerance, but the contribution of Them1 in liver is unclear. To examine its liver-specific functions, we created conditional transgenic mice, which, when bred to Them1-/- mice and activated, expressed Them1 exclusively in the liver. Mice with liver-specific Them1 expression exhibited no changes in energy expenditure. Rates of fatty acid oxidation were increased, whereas hepatic VLDL triglyceride secretion rates were decreased by hepatic Them1 expression. When fed a high-fat diet, Them1 expression in liver promoted excess steatosis in the setting of reduced rates of fatty acid oxidation and preserved glycerolipid synthesis. Liver-specific Them1 expression did not influence glucose tolerance or insulin sensitivity, but did promote hepatic gluconeogenesis in high-fat-fed animals. This was attributable to the generation of excess fatty acids, which activated PPARα and promoted expression of gluconeogenic genes. These findings reveal a regulatory role for Them1 in hepatocellular fatty acid trafficking.
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Affiliation(s)
- Anal Desai
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021
| | - Michele Alves-Bezerra
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021
| | - Yingxia Li
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021
| | - Cafer Ozdemir
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118
| | - Curtis J Bare
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021
| | - Yue Li
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215
| | - Susan J Hagen
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215
| | - David E Cohen
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021
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30
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Abstract
Triglyceride molecules represent the major form of storage and transport of fatty acids within cells and in the plasma. The liver is the central organ for fatty acid metabolism. Fatty acids accrue in liver by hepatocellular uptake from the plasma and by de novo biosynthesis. Fatty acids are eliminated by oxidation within the cell or by secretion into the plasma within triglyceride-rich very low-density lipoproteins. Notwithstanding high fluxes through these pathways, under normal circumstances the liver stores only small amounts of fatty acids as triglycerides. In the setting of overnutrition and obesity, hepatic fatty acid metabolism is altered, commonly leading to the accumulation of triglycerides within hepatocytes, and to a clinical condition known as nonalcoholic fatty liver disease (NAFLD). In this review, we describe the current understanding of fatty acid and triglyceride metabolism in the liver and its regulation in health and disease, identifying potential directions for future research. Advances in understanding the molecular mechanisms underlying the hepatic fat accumulation are critical to the development of targeted therapies for NAFLD. © 2018 American Physiological Society. Compr Physiol 8:1-22, 2018.
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Affiliation(s)
- Michele Alves-Bezerra
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
| | - David E Cohen
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
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31
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Tillander V, Alexson SEH, Cohen DE. Deactivating Fatty Acids: Acyl-CoA Thioesterase-Mediated Control of Lipid Metabolism. Trends Endocrinol Metab 2017; 28:473-484. [PMID: 28385385 PMCID: PMC5474144 DOI: 10.1016/j.tem.2017.03.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/01/2017] [Indexed: 12/28/2022]
Abstract
The cellular uptake of free fatty acids (FFA) is followed by esterification to coenzyme A (CoA), generating fatty acyl-CoAs that are substrates for oxidation or incorporation into complex lipids. Acyl-CoA thioesterases (ACOTs) constitute a family of enzymes that hydrolyze fatty acyl-CoAs to form FFA and CoA. Although biochemically and biophysically well characterized, the metabolic functions of these enzymes remain incompletely understood. Existing evidence suggests regulatory roles in controlling rates of peroxisomal and mitochondrial fatty acyl-CoA oxidation, as well as in the subcellular trafficking of fatty acids. Emerging data implicate ACOTs in the pathogenesis of metabolic diseases, suggesting that better understanding their pathobiology could reveal unique targets in the management of obesity, diabetes, and nonalcoholic fatty liver disease.
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Affiliation(s)
- Veronika Tillander
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, 14186, Sweden
| | - Stefan E H Alexson
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, 14186, Sweden
| | - David E Cohen
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA.
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32
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Wall VZ, Barnhart S, Kramer F, Kanter JE, Vivekanandan-Giri A, Pennathur S, Bolego C, Ellis JM, Gijón MA, Wolfgang MJ, Bornfeldt KE. Inflammatory stimuli induce acyl-CoA thioesterase 7 and remodeling of phospholipids containing unsaturated long (≥C20)-acyl chains in macrophages. J Lipid Res 2017; 58:1174-1185. [PMID: 28416579 DOI: 10.1194/jlr.m076489] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Indexed: 01/01/2023] Open
Abstract
Acyl-CoA thioesterase 7 (ACOT7) is an intracellular enzyme that converts acyl-CoAs to FFAs. ACOT7 is induced by lipopolysaccharide (LPS); thus, we investigated downstream effects of LPS-induced induction of ACOT7 and its role in inflammatory settings in myeloid cells. Enzymatic thioesterase activity assays in WT and ACOT7-deficient macrophage lysates indicated that endogenous ACOT7 contributes a significant fraction of total acyl-CoA thioesterase activity toward C20:4-, C20:5-, and C22:6-CoA, but contributes little activity toward shorter acyl-CoA species. Lipidomic analyses revealed that LPS causes a dramatic increase, primarily in bis(monoacylglycero)phosphate species containing long (≥C20) polyunsaturated acyl-chains in macrophages, and that the limited effect observed by ACOT7 deficiency is restricted to glycerophospholipids containing 20-carbon unsaturated acyl-chains. Furthermore, ACOT7 deficiency did not detectably alter the ability of LPS to induce cytokines or prostaglandin E2 production in macrophages. Consistently, although ACOT7 was induced in macrophages from diabetic mice, hematopoietic ACOT7 deficiency did not alter the stimulatory effect of diabetes on systemic inflammation or atherosclerosis in LDL receptor-deficient mice. Thus, inflammatory stimuli induce ACOT7 and remodeling of phospholipids containing unsaturated long (≥C20)-acyl chains in macrophages, and, although ACOT7 has preferential thioesterase activity toward these lipid species, loss of ACOT7 has no major detrimental effect on macrophage inflammatory phenotypes.≥.
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Affiliation(s)
- Valerie Z Wall
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA.,Division of Metabolism, Endocrinology and Nutrition, and Department of Pathology, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Shelley Barnhart
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Farah Kramer
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Jenny E Kanter
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | | | | | - Chiara Bolego
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Jessica M Ellis
- Department of Nutrition Science, Purdue University, West Lafayette, IN.,Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Miguel A Gijón
- Department of Pharmacology, University of Colorado Denver, Aurora, CO
| | - Michael J Wolfgang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Karin E Bornfeldt
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA .,Division of Metabolism, Endocrinology and Nutrition, and Department of Pathology, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
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Ohtomo T, Ino K, Miyashita R, Chigira M, Nakamura M, Someya K, Inaba N, Fujita M, Takagi M, Yamada J. Chronic high-fat feeding impairs adaptive induction of mitochondrial fatty acid combustion-associated proteins in brown adipose tissue of mice. Biochem Biophys Rep 2017; 10:32-38. [PMID: 28955734 PMCID: PMC5614659 DOI: 10.1016/j.bbrep.2017.02.002] [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: 07/25/2016] [Revised: 02/04/2017] [Accepted: 02/15/2017] [Indexed: 11/13/2022] Open
Abstract
Since brown adipose tissue (BAT) is involved in thermogenesis using fatty acids as a fuel, BAT activation is a potential strategy for treating obesity and diabetes. However, whether BAT fatty acid combusting capacity is preserved in these conditions has remained unclear. We therefore evaluated expression levels of fatty acid oxidation-associated enzymes and uncoupling protein 1 (Ucp1) in BAT by western blot using a diet-induced obesity C57BL/6J mouse model. In C57BL/6J mice fed a high-fat diet (HFD) over 2–4 weeks, carnitine palmitoyltransferase 2 (Cpt2), acyl-CoA thioesterase (Acot) 2, Acot11 and Ucp1 levels were significantly increased compared with baseline and control low-fat diet (LFD)-fed mice. Similar results were obtained in other mouse strains, including ddY, ICR and KK-Ay, but the magnitudes of the increase in Ucp1 level were much smaller than in C57BL/6J mice, with decreased Acot11 levels after HFD-feeding. In C57BL/6J mice, increased levels of these mitochondrial proteins declined to near baseline levels after a longer-term HFD-feeding (20 weeks), concurrent with the accumulation of unilocular, large lipid droplets in brown adipocytes. Extramitochondrial Acot11 and acyl-CoA oxidase remained elevated. Treatment of mice with Wy-14,643 also increased these proteins, but was less effective than 4 week-HFD, suggesting that mechanisms other than peroxisome proliferator-activated receptor α were also involved in the upregulation. These results suggest that BAT enhances its fatty acid combusting capacity in response to fat overload, however profound obesity deprives BAT of the responsiveness to fat, possibly via mitochondrial alteration. BAT activation is a potential strategy for treating obesity and diabetes. BAT enhances its fatty acid combusting capacity in response to high-fat feeding. Profound obesity deprives BAT of the responsiveness to fat overload. Susceptibility to BAT activation could depend on the degree of obesity.
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Key Words
- Acot, acyl-CoA thioesterase
- Acox, acyl-CoA oxidase
- Acyl-CoA thioesterase
- BAT, brown adipose tissue
- Brown adipose tissue
- Cpt, carnitine palmitoyltransferase
- ETC, electron transport chain
- Fatty acid oxidation
- HFD and LFD, high- and low-fat diet
- Obesity
- Ppar, peroxisome proliferator-activated receptor
- SNS, sympathetic nervous system
- TCA, tricarboxylic acid
- TG, triglyceride
- Ucp, uncoupling protein
- Uncoupling protein
- WAT, white adipose tissue
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Affiliation(s)
- Takayuki Ohtomo
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Kanako Ino
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Ryota Miyashita
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Maya Chigira
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Masahiko Nakamura
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Koji Someya
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Niro Inaba
- Center for the Advancement of Pharmaceutical Education, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Mariko Fujita
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Mitsuhiro Takagi
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Junji Yamada
- Department of Pharmacotherapeutics, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
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