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Hao L, Khan MSH, Zu Y, Liu J, Wang S. Thermoneutrality Inhibits Thermogenic Markers and Exacerbates Nonalcoholic Fatty Liver Disease in Mice. Int J Mol Sci 2024; 25:8482. [PMID: 39126051 PMCID: PMC11312964 DOI: 10.3390/ijms25158482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 07/30/2024] [Accepted: 08/01/2024] [Indexed: 08/12/2024] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) affects over a third of the US population and 25% globally, with current treatments proving ineffective. This study investigates whether manipulating brown adipose tissue (BAT) and beige fat activity by housing C57BL/6J mice at thermoneutral (27 °C) or standard temperatures (22 °C) impacts NAFLD development. Male mice were fed either a chow diet (CHD) or a "fast food" diet (FFD) for 10 weeks. Mice at 27 °C had reduced food intake but increased body weight and plasma leptin levels. FFD-fed mice at 27 °C had greater liver weight (2.6 vs. 1.8 g), triglyceride content (7.6 vs. 3.9 mg/g), and hepatic steatosis compared to those at 22 °C. Gene expression of fatty acid synthase, sterol regulatory element-binding protein 1, and fatty acid translocase CD36 was elevated in FFD-fed mice at 27 °C, but not in CHD-fed mice. Thermoneutral housing also reduced expression of thermogenic markers in BAT and inguinal white adipose tissue (WAT) and caused BAT whitening. In conclusion, thermoneutrality inhibits thermogenic markers and exacerbates NAFLD. Activating BAT or promoting WAT browning via cold exposure or other stimuli may offer a strategy for managing NAFLD.
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Affiliation(s)
- Lei Hao
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX 79409, USA; (M.S.H.K.); (Y.Z.); (J.L.)
- Department of Allied and Public Health, Indiana University of Pennsylvania, Indian, PA 15705, USA
| | - Md Shahjalal Hossain Khan
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX 79409, USA; (M.S.H.K.); (Y.Z.); (J.L.)
| | - Yujiao Zu
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX 79409, USA; (M.S.H.K.); (Y.Z.); (J.L.)
| | - Jie Liu
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX 79409, USA; (M.S.H.K.); (Y.Z.); (J.L.)
| | - Shu Wang
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX 79409, USA; (M.S.H.K.); (Y.Z.); (J.L.)
- College of Health Solutions, Arizona State University, Phoenix, AZ 85004, USA
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Thermogenic Adipose Redox Mechanisms: Potential Targets for Metabolic Disease Therapies. Antioxidants (Basel) 2023; 12:antiox12010196. [PMID: 36671058 PMCID: PMC9854447 DOI: 10.3390/antiox12010196] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/07/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Metabolic diseases, such as diabetes and non-alcoholic fatty liver disease (NAFLD), have several negative health outcomes on affected humans. Dysregulated energy metabolism is a key component underlying the pathophysiology of these conditions. Adipose tissue is a fundamental regulator of energy homeostasis that utilizes several redox reactions to carry out the metabolism. Brown and beige adipose tissues, in particular, perform highly oxidative reactions during non-shivering thermogenesis to dissipate energy as heat. The appropriate regulation of energy metabolism then requires coordinated antioxidant mechanisms to counterbalance the oxidation reactions. Indeed, non-shivering thermogenesis activation can cause striking changes in concentrations of both oxidants and antioxidants in order to adapt to various oxidative environments. Current therapeutic options for metabolic diseases either translate poorly from rodent models to humans (in part due to the challenges of creating a physiologically relevant rodent model) or tend to have numerous side effects, necessitating novel therapies. As increased brown adipose tissue activity results in enhanced energy expenditure and is associated with beneficial effects on metabolic health, such as decreased obesity, it has gathered great interest as a modulator of metabolic disease. One potential reason for the beneficial health effects may be that although non-shivering thermogenesis is enormously oxidative, it is also associated with decreased oxidant formation after its activation. However, targeting its redox mechanisms specifically to alter metabolic disease remains an underexplored area. Therefore, this review will discuss the role of adipose tissue in energy homeostasis, non-shivering thermogenesis in adults, and redox mechanisms that may serve as novel therapeutic targets of metabolic disease.
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Pharmacokinetics of T0901317 in mouse serum and tissues using a validated UFLC-IT-TOF/MS method. J Pharm Biomed Anal 2020; 189:113420. [PMID: 32593849 DOI: 10.1016/j.jpba.2020.113420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 06/04/2020] [Accepted: 06/07/2020] [Indexed: 01/08/2023]
Abstract
T0901317, a liver X receptors (LXRs) agonist with high-affinity, is widely used to explore the functions of LXRs in various diseases such as atherosclerosis and Alzheimer's disease. However, there is currently little information available about the pharmacokinetics (PK) behavior of T0901317. Here we established a novel ultrafast liquid chromatography-high resolution mass spectrometry method to quantify the concentration of T0901317 in serum, liver, and brain. The chromatographic separation was attained on a C18 (2.1 × 100 mm, 1.8 μm) column using acetonitrile and 0.1 % of formic acid in water as mobile phase operated in gradient elution mode. The mass detection was carried out using negative ions m/z 479.9809 and 322.0882 for T0901317 and internal standard, respectively. The proposed method was fully validated according to the FDA guidelines, and it generally provides good results in terms of linearity (r2 > 0.99), precision (RSD < 18 % and 12 % for LLOQ and other QC levels, respectively), accuracy (between 92.30 % and 108.16 %), and matrix effect (between 86.56 % and 113.81 %). We then for the first time determined and computed the PK parameters of T0901317 in mouse after intraperitoneal administration of a 20 mg/kg dosage. The peak times (Tmax) in serum, liver, and brain were 1.5, 1.5, and 4 h, respectively, while the half-lives (t1/2) were 4.9, 3.3, and 4.5 h, respectively. Taken together, our results provide a significant choice to study the PK property of T0901317, from which the design of the dosing and sampling protocols of LXRs receptor-antagonist experiments employing T0901317 can also benefit.
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Pu S, Wu X, Yang X, Zhang Y, Dai Y, Zhang Y, Wu X, Liu Y, Cui X, Jin H, Cao J, Li R, Cai J, Cao Q, Hu L, Gao Y. The Therapeutic Role of Xenobiotic Nuclear Receptors Against Metabolic Syndrome. Curr Drug Metab 2019; 20:15-22. [PMID: 29886826 DOI: 10.2174/1389200219666180611083155] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 04/05/2018] [Accepted: 05/29/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Diabetes, with an increased prevalence and various progressive complications, has become a significant global health challenge. The concrete mechanisms responsible for the development of diabetes still remain incompletely unknown, although substantial researches have been conducted to search for the effective therapeutic targets. This review aims to reveal the novel roles of Xenobiotic Nuclear Receptors (XNRs), including the Peroxisome Proliferator-Activated Receptor (PPAR), the Farnesoid X Receptor (FXR), the Liver X Receptor (LXR), the Pregnane X Receptor (PXR) and the Constitutive Androstane Receptor (CAR), in the development of diabetes and provide potential strategies for research and treatment of metabolic diseases. METHODS We retrieved a large number of original data about these five XNRs and organized to focus on their recently discovered functions in diabetes and its complications. RESULTS Increasing evidences have suggested that PPAR, FXR, LXR ,PXR and CAR are involved in the development of diabetes and its complications through different mechanisms, including the regulation of glucose and lipid metabolism, insulin and inflammation response and related others. CONCLUSION PPAR, FXR, LXR, PXR, and CAR, as the receptors for numerous natural or synthetic compounds, may be the most effective therapeutic targets in the treatment of metabolic diseases.
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Affiliation(s)
- Shuqi Pu
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiaojie Wu
- Department of Immunology, Binzhou Medical University, Yantai, China
| | - Xiaoying Yang
- Jiangsu Key Laboratory of Immunity and Metabolism, Department of Pathogen Biology and Immunology and Laboratory of Infection and Immunity, Xuzhou Medical University, Xuzhou, China
| | - Yunzhan Zhang
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yunkai Dai
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yueling Zhang
- Department of Operating Theatre, Binzhou People's Hospital, Binzhou, China
| | - Xiaoting Wu
- Department of Operating Theatre, Binzhou People's Hospital, Binzhou, China
| | - Yan Liu
- Department of Immunology, Binzhou Medical University, Yantai, China
| | - Xiaona Cui
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Research Center for Biochemistry and Molecular Biology, Xuzhou Medical University, Xuzhou, China
| | - Haiyong Jin
- Department of Otolaryngology, the Second Affiliated Hospital & Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jianhong Cao
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Ruliu Li
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiazhong Cai
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qizhi Cao
- Department of Immunology, Binzhou Medical University, Yantai, China
| | - Ling Hu
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yong Gao
- PI-WEI Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
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Xiong T, Li Z, Huang X, Lu K, Xie W, Zhou Z, Tu J. TO901317 inhibits the development of hepatocellular carcinoma by LXRα/Glut1 decreasing glycometabolism. Am J Physiol Gastrointest Liver Physiol 2019; 316:G598-G607. [PMID: 30817182 DOI: 10.1152/ajpgi.00061.2018] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This study was conducted to observe the effect and possible mechanism of TO901317 in vivo and in vitro to provide a new basis for the targeted therapy of hepatocellular carcinoma (HCC). The expressions of liver X receptor (LXR)-α, glucose transporter (Glut)-1, proliferating cell nuclear antigen (PCNA), and matrix metalloproteinase (MMP)-9 were analyzed from HCC public database (NCBI PubMed database). The result showed that LXRα was downregulated, whereas Glut1, PCNA, and MMP9 were upregulated in human HCC compared with normal liver. Furthermore, LXRα mRNA was negatively correlated with Glut1 mRNA. At the same time, HCC cells were cultivated in vitro and axillary injected in nude mice to establish the xenograft model. The xenograft in the TO901317-treated group was slower and smaller than the control group. The protein expression of LXRα, Glut1, and MMP9 could be detected by Western blot and glucose level. As a result, TO901317 could inhibit the cell proliferation of HCC in a dose-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. With the increase of TO901317 concentration, the cellular glucose concentration and ATP level were gradually decreased. Western blot results showed TO901317 could upregulate LXRα expression but downregulate MMP9 and Glut1 expression. Transwell and wound-healing analysis confirmed that, by increasing the concentration of TO901317, the cell invasion and migration were both decreased. LXRα small-interfering RNA (siRNA) could relieve the suppression effect of TO901317 on the cell invasion and migration and the expression of LXRα, Glut1, and MMP9. The glucose concentration was also raised. TO901317 could repress the progress of HCC cells by reducing the glucose concentration, upregulating LXRα expression, but downregulating the expression of Glut1 and MMP9. NEW & NOTEWORTHY This subject confirmed that TO901317, a specific liver X receptor agonist, could inhibit the progression of liver cancer through upregulating liver X receptor-α, downregulating the expression of glucose transporter-1 and matrix metalloproteinase-9, and decreasing the glucose content in SMMC-7721 and HepG2 cells.
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Affiliation(s)
- Ting Xiong
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan, People's Republic of China.,School of Pharmacy, Changsha Medical University, Hunan, People's Republic of China
| | - Zihan Li
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan, People's Republic of China
| | - Xuelong Huang
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan, People's Republic of China
| | - Kaiqiang Lu
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan, People's Republic of China
| | - Weiquan Xie
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan, People's Republic of China
| | - Zhigang Zhou
- Department of Anesthesia, the First Affiliated Hospital, University of South China, Hengyang, Hunan, People's Republic of China
| | - Jian Tu
- Institute of Pharmacy and Pharmacology, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hunan, People's Republic of China
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Yau WW, Singh BK, Lesmana R, Zhou J, Sinha RA, Wong KA, Wu Y, Bay BH, Sugii S, Sun L, Yen PM. Thyroid hormone (T 3) stimulates brown adipose tissue activation via mitochondrial biogenesis and MTOR-mediated mitophagy. Autophagy 2018; 15:131-150. [PMID: 30209975 DOI: 10.1080/15548627.2018.1511263] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The thyroid hormone triiodothyronine (T3) activates thermogenesis by uncoupling electron transport from ATP synthesis in brown adipose tissue (BAT) mitochondria. Although T3 can induce thermogenesis by sympathetic innervation, little is known about its cell autonomous effects on BAT mitochondria. We thus examined effects of T3 on mitochondrial activity, autophagy, and metabolism in primary brown adipocytes and BAT and found that T3 increased fatty acid oxidation and mitochondrial respiration as well as autophagic flux, mitophagy, and mitochondrial biogenesis. Interestingly, there was no significant induction of intracellular reactive oxygen species (ROS) despite high mitochondrial respiration and UCP1 induction by T3. However, when cells were treated with Atg5 siRNA to block autophagy, induction of mitochondrial respiration by T3 decreased, and was accompanied by ROS accumulation, demonstrating a critical role for autophagic mitochondrial turnover. We next generated an Atg5 conditional knockout mouse model (Atg5 cKO) by injecting Ucp1 promoter-driven Cre-expressing adenovirus into Atg5Flox/Flox mice to examine effects of BAT-specific autophagy on thermogenesis in vivo. Hyperthyroid Atg5 cKO mice exhibited lower body temperature than hyperthyroid or euthyroid control mice. Metabolomic analysis showed that T3 increased short and long chain acylcarnitines in BAT, consistent with increased β-oxidation. T3 also decreased amino acid levels, and in conjunction with SIRT1 activation, decreased MTOR activity to stimulate autophagy. In summary, T3 has direct effects on mitochondrial autophagy, activity, and turnover in BAT that are essential for thermogenesis. Stimulation of BAT activity by thyroid hormone or its analogs may represent a potential therapeutic strategy for obesity and metabolic diseases. Abbreviations: ACACA: acetyl-Coenzyme A carboxylase alpha; AMPK: AMP-activated protein kinase; Acsl1: acyl-CoA synthetase long-chain family member 1; ATG5: autophagy related 5; ATG7: autophagy related 7; ATP: adenosine triphosphate; BAT: brown adipose tissue; cKO: conditional knockout; COX4I1: cytochrome c oxidase subunit 4I1; Cpt1b: carnitine palmitoyltransferase 1b, muscle; CQ: chloroquine; DAPI: 4',6-diamidino-2-phenylindole; DIO2: deiodinase, iodothyronine, type 2; DMEM: Dulbecco's modified Eagle's medium; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; Fabp4: fatty acid binding protein 4, adipocyte; FBS: fetal bovine serum; FCCP: carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone; FGF: fibroblast growth factor; FOXO1: forkhead box O1; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; Gpx1: glutathione peroxidase 1; Lipe: lipase, hormone sensitive; MAP1LC3B: microtubule-associated protein 1 light chain 3; mRNA: messenger RNA; MTORC1: mechanistic target of rapamycin kinase complex 1; NAD: nicotinamide adenine dinucleotide; Nrf1: nuclear respiratory factor 1; OCR: oxygen consumption rate; PBS: phosphate-buffered saline; PCR: polymerase chain reaction; PPARGC1A: peroxisome proliferative activated receptor, gamma, coactivator 1 alpha; Pnpla2: patatin-like phospholipase domain containing 2; Prdm16: PR domain containing 16; PRKA: protein kinase, AMP-activated; RPS6KB: ribosomal protein S6 kinase; RFP: red fluorescent protein; ROS: reactive oxygen species; SD: standard deviation; SEM: standard error of the mean; siRNA: small interfering RNA; SIRT1: sirtuin 1; Sod1: superoxide dismutase 1, soluble; Sod2: superoxide dismutase 2, mitochondrial; SQSTM1: sequestosome 1; T3: 3,5,3'-triiodothyronine; TFEB: transcription factor EB; TOMM20: translocase of outer mitochondrial membrane 20; UCP1: uncoupling protein 1 (mitochondrial, proton carrier); ULK1: unc-51 like kinase 1; VDAC1: voltage-dependent anion channel 1; WAT: white adipose tissue.
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Affiliation(s)
- Winifred W Yau
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore
| | - Brijesh K Singh
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore
| | - Ronny Lesmana
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore.,b Physiology Division, Department of Anatomy, Physiology and Biology Cell, Faculty of Medicine , Universitas Padjadjaran , Bandung , Indonesia.,c Central laboratory , Universitas Padjadjaran , Bandung , Indonesia
| | - Jin Zhou
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore
| | - Rohit A Sinha
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore.,d Department of Endocrinology , Sanjay Gandhi Postgraduate Institute of Medical Sciences , Lucknow , India
| | - Kiraely A Wong
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore
| | - Yajun Wu
- e Department of Anatomy , Yong Loo Lin School of Medicine, National University of Singapore , Singapore
| | - Boon-Huat Bay
- e Department of Anatomy , Yong Loo Lin School of Medicine, National University of Singapore , Singapore
| | - Shigeki Sugii
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore.,f Fat Metabolism and Stem Cell Group , Singapore Bioimaging Consortium, A*STAR , Singapore
| | - Lei Sun
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore
| | - Paul M Yen
- a Laboratory of Hormonal Regulation , Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore.,g Sarah W. Stedman Nutrition and Metabolism Center, Departments of Medicine and Pharmacology and Cancer Biology , Duke University Medical Center , Durham , NC , USA
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Maczewsky J, Sikimic J, Bauer C, Krippeit-Drews P, Wolke C, Lendeckel U, Barthlen W, Drews G. The LXR Ligand T0901317 Acutely Inhibits Insulin Secretion by Affecting Mitochondrial Metabolism. Endocrinology 2017; 158:2145-2154. [PMID: 28449117 DOI: 10.1210/en.2016-1941] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 04/20/2017] [Indexed: 12/15/2022]
Abstract
The role of liver X receptor (LXR) in pancreatic β-cell physiology and pathophysiology is still unclear. It has been postulated that chronic LXR activation in β-cells induces lipotoxicity, a key step in the development of β-cell dysfunction, which accompanies type 2 diabetes mellitus. In most of these studies, the LXR ligand T0901317 has been administered chronically in the micromolar range to study the significance of LXR activation. In the current study, we have evaluated acute effects of T0901317 on stimulus-secretion coupling of β-cells. We found that 10 µM T0901317 completely suppressed oscillations of the cytosolic Ca2+ concentration induced by 15 mM glucose. Obviously, this effect was due to inhibition of mitochondrial metabolism. T0901317 markedly depolarized the mitochondrial membrane potential, thus inhibiting adenosine triphosphate (ATP) production and reducing the cytosolic ATP concentration. This led in turn to a huge increase in KATP current and hyperpolarization of the cell membrane potential. Eventually, T0901317 inhibited glucose-induced insulin secretion. These effects were rapid in on-set and not compatible with the activation of a nuclear receptor. In vivo, T0901317 acutely increased the blood glucose concentration after intraperitoneal application. In summary, these data clearly demonstrate that T0901317 exerts acute effects on stimulus-secretion coupling. This observation questions the chronic use of T0901317 and limits the interpretation of results obtained under these experimental conditions.
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Affiliation(s)
- Jonas Maczewsky
- Institute of Pharmacy, Department of Pharmacology, University of Tübingen, 72076 Tübingen, Germany
| | - Jelena Sikimic
- Institute of Pharmacy, Department of Pharmacology, University of Tübingen, 72076 Tübingen, Germany
| | - Cita Bauer
- Institute of Pharmacy, Department of Pharmacology, University of Tübingen, 72076 Tübingen, Germany
| | - Peter Krippeit-Drews
- Institute of Pharmacy, Department of Pharmacology, University of Tübingen, 72076 Tübingen, Germany
| | - Carmen Wolke
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Uwe Lendeckel
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Winfried Barthlen
- Department of Pediatric Surgery, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Gisela Drews
- Institute of Pharmacy, Department of Pharmacology, University of Tübingen, 72076 Tübingen, Germany
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Jeremic N, Chaturvedi P, Tyagi SC. Browning of White Fat: Novel Insight Into Factors, Mechanisms, and Therapeutics. J Cell Physiol 2016; 232:61-8. [PMID: 27279601 DOI: 10.1002/jcp.25450] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 06/07/2016] [Indexed: 12/16/2022]
Abstract
What is more interesting about brown adipose tissue (BAT) is its ability to provide thermogenesis, protection against obesity by clearing triglycerides, releasing batokines, and mitigating insulin resistance. White adipose tissue (WAT) on the other hand stores excess energy and secretes some endocrine factors like leptin for regulating satiety. For the last decade there has been an increasing interest in the browning of fat keeping in view its beneficial effects on metabolic disorders and protection in the form of perivascular fat. Obesity is one such metabolic disorder that leads to significant morbidity and mortality from obesity-related disorders such as type 2 diabetes mellitus (T2D) and cardiovascular disease risk. Browning of white fat paves the way to restrict obesity and obesity related disorders. Although exercise has been the most common factor for fat browning; however, there are other factors that involve: (1) beta aminoisobutyric acid (BAIBA); (2) gamma amino butyric acid (GABA); (3) PPARɣ agonists; (4) JAK inhibition; and (5) IRISIN. In this review, we propose two novel factors musclin and TFAM for fat browning. Musclin a myokine released from muscles during exercise activates PPARɣ which induces browning of WAT that has beneficial metabolic and cardiac effects. TFAM is a transcription factor that induces mitochondrial biogenesis. Since BAT is rich in mitochondria, higher expression of TFAM in WAT or TFAM treatment in WAT cells can induce browning of WAT. We propose that fat browning can be used as a therapeutic tool for metabolic disorders and cardiovascular diseases. J. Cell. Physiol. 232: 61-68, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Nevena Jeremic
- Department of Physiology, University of Louisville, Louisville, Kentucky
| | - Pankaj Chaturvedi
- Department of Physiology, University of Louisville, Louisville, Kentucky
| | - Suresh C Tyagi
- Department of Physiology, University of Louisville, Louisville, Kentucky.
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