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Lee K, Kim HJ, Kim JY, Shim JJ, Lee JH. A Mixture of Lactobacillus HY7601 and KY1032 Regulates Energy Metabolism in Adipose Tissue and Improves Cholesterol Disposal in High-Fat-Diet-Fed Mice. Nutrients 2024; 16:2570. [PMID: 39125449 PMCID: PMC11314552 DOI: 10.3390/nu16152570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2024] [Revised: 07/30/2024] [Accepted: 08/03/2024] [Indexed: 08/12/2024] Open
Abstract
We aimed to characterize the anti-obesity and anti-atherosclerosis effects of Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032 using high-fat diet (HFD)-fed obese C57BL/6 mice. We divided the mice into control (CON), HFD, HFD with 108 CFU/kg/day probiotics (HFD + KL, HY7301:KY1032 = 1:1), and HFD with 109 CFU/kg/day probiotics (HFD + KH, HY7301:KY1032 = 1:1) groups and fed/treated them during 7 weeks. The body mass, brown adipose tissue (BAT), inguinal white adipose tissue (iWAT), and epididymal white adipose tissue (eWAT) masses and the total cholesterol and triglyceride concentrations were remarkably lower in probiotic-treated groups than in the HFD group in a dose-dependent manner. In addition, the expression of uncoupling protein 1 in the BAT, iWAT, and eWAT was significantly higher in probiotic-treated HFD mice than in the HFD mice, as demonstrated by immunofluorescence staining and Western blotting. We also measured the expression of cholesterol transport genes in the liver and jejunum and found that the expression of those encoding liver-X-receptor α, ATP-binding cassette transporters G5 and G8, and cholesterol 7α-hydroxylase were significantly higher in the HFD + KH mice than in the HFD mice. Thus, a Lactobacillus HY7601 and KY1032 mixture with 109 CFU/kg/day concentration can assist with body weight regulation through the management of lipid metabolism and thermogenesis.
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Affiliation(s)
| | | | - Joo-Yun Kim
- R&BD Center, Hy Co., Ltd., 22 Giheungdanji-ro 24 Beon-gil, Giheung-gu, Yongin-si 17086, Republic of Korea; (K.L.); (H.-J.K.); (J.-J.S.); (J.-H.L.)
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Jamerson LE, Bradshaw PC. The Roles of White Adipose Tissue and Liver NADPH in Dietary Restriction-Induced Longevity. Antioxidants (Basel) 2024; 13:820. [PMID: 39061889 PMCID: PMC11273496 DOI: 10.3390/antiox13070820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/01/2024] [Accepted: 07/03/2024] [Indexed: 07/28/2024] Open
Abstract
Dietary restriction (DR) protocols frequently employ intermittent fasting. Following a period of fasting, meal consumption increases lipogenic gene expression, including that of NADPH-generating enzymes that fuel lipogenesis in white adipose tissue (WAT) through the induction of transcriptional regulators SREBP-1c and CHREBP. SREBP-1c knockout mice, unlike controls, did not show an extended lifespan on the DR diet. WAT cytoplasmic NADPH is generated by both malic enzyme 1 (ME1) and the pentose phosphate pathway (PPP), while liver cytoplasmic NADPH is primarily synthesized by folate cycle enzymes provided one-carbon units through serine catabolism. During the daily fasting period of the DR diet, fatty acids are released from WAT and are transported to peripheral tissues, where they are used for beta-oxidation and for phospholipid and lipid droplet synthesis, where monounsaturated fatty acids (MUFAs) may activate Nrf1 and inhibit ferroptosis to promote longevity. Decreased WAT NADPH from PPP gene knockout stimulated the browning of WAT and protected from a high-fat diet, while high levels of NADPH-generating enzymes in WAT and macrophages are linked to obesity. But oscillations in WAT [NADPH]/[NADP+] from feeding and fasting cycles may play an important role in maintaining metabolic plasticity to drive longevity. Studies measuring the WAT malate/pyruvate as a proxy for the cytoplasmic [NADPH]/[NADP+], as well as studies using fluorescent biosensors expressed in the WAT of animal models to monitor the changes in cytoplasmic [NADPH]/[NADP+], are needed during ad libitum and DR diets to determine the changes that are associated with longevity.
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Affiliation(s)
| | - Patrick C. Bradshaw
- Department of Biomedical Sciences, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
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Burkhardt P, Palma-Duran SA, Tuck ARR, Norgren K, Li X, Nikiforova V, Griffin JL, Munic Kos V. Environmental chemicals change extracellular lipidome of mature human white adipocytes. CHEMOSPHERE 2024; 349:140852. [PMID: 38048832 DOI: 10.1016/j.chemosphere.2023.140852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 10/25/2023] [Accepted: 11/28/2023] [Indexed: 12/06/2023]
Abstract
Certain environmental chemicals affect the body's energy balance and are known as metabolism disrupting chemicals (MDCs). MDCs have been implicated in the development of metabolic diseases, such as obesity and type 2 diabetes. In contrast to their well-known impact on developing adipocytes, MDC effects leading to altered energy balance and development of insulin resistance in mature white adipocytes, constituents of adult adipose tissue, are largely unclear. Here, we investigated the effects of six well-established environmental MDCs (bisphenol A (BPA), perfluorooctanoic acid (PFOA), triclosan (TCS), p,p-dichlorodiphenyl-dichloroethylene (ppDDE), tributyltin chloride (TBT) and triphenyl phosphate (TPP)) on mature human white adipocytes derived from mesenchymal stem cells in vitro. We aimed to identify biomarkers and sensitive endpoints of their metabolism disrupting effects. While most of the tested exposures had no effect on adipocyte glucose consumption, lipid storage and assessed gene expression endpoints, the highest concentration of triclosan affected the total lipid storage and adipocyte size, as well as glucose consumption and mRNA expression of the glucose transporter GLUT1, leptin and adiponectin. Additionally, an increased expression of adiponectin was observed with TPP and the positive control PPARγ agonist rosiglitazone. In contrast, the lipidomic analysis of the cell culture medium after a 3-day exposure was extremely sensitive and revealed concentration-dependent changes in the extracellular lipidome of adipocytes exposed to nearly all studied chemicals. While some of the extracellular lipidome changes were specific for the MDC used, some effects were found common to several tested chemicals and included increases in lysophosphatidylcholines, glycerophospholipids and ceramides and a decrease in fatty acids, with possible implications in inflammation, lipid and glucose uptake. This study points to early signs of metabolic disruption and likely systemic effects of mature adipocyte exposure to environmental chemicals, as well as to the need to include lipidomic endpoints in the assessment of adverse effects of MDCs.
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Affiliation(s)
- Paula Burkhardt
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Susana Alejandra Palma-Duran
- Metabolomics STP, The Francis Crick Institute, London, UK; Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK; Department of Food Science, Research Center in Food and Development A.C., Hermosillo, Mexico
| | - Astrud R R Tuck
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Kalle Norgren
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Xinyi Li
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Violetta Nikiforova
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Julian L Griffin
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK; The Rowett Institute, University of Aberdeen, Aberdeen, UK
| | - Vesna Munic Kos
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
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Jeon YG, Kim YY, Lee G, Kim JB. Physiological and pathological roles of lipogenesis. Nat Metab 2023; 5:735-759. [PMID: 37142787 DOI: 10.1038/s42255-023-00786-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 03/15/2023] [Indexed: 05/06/2023]
Abstract
Lipids are essential metabolites, which function as energy sources, structural components and signalling mediators. Most cells are able to convert carbohydrates into fatty acids, which are often converted into neutral lipids for storage in the form of lipid droplets. Accumulating evidence suggests that lipogenesis plays a crucial role not only in metabolic tissues for systemic energy homoeostasis but also in immune and nervous systems for their proliferation, differentiation and even pathophysiological roles. Thus, excessive or insufficient lipogenesis is closely associated with aberrations in lipid homoeostasis, potentially leading to pathological consequences, such as dyslipidaemia, diabetes, fatty liver, autoimmune diseases, neurodegenerative diseases and cancers. For systemic energy homoeostasis, multiple enzymes involved in lipogenesis are tightly controlled by transcriptional and post-translational modifications. In this Review, we discuss recent findings regarding the regulatory mechanisms, physiological roles and pathological importance of lipogenesis in multiple tissues such as adipose tissue and the liver, as well as the immune and nervous systems. Furthermore, we briefly introduce the therapeutic implications of lipogenesis modulation.
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Affiliation(s)
- Yong Geun Jeon
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Ye Young Kim
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Gung Lee
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Jae Bum Kim
- Center for Adipocyte Structure and Function, Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul, South Korea.
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Florijn BW, Duijs JMGJ, Klaver M, Kuipers EN, Kooijman S, Prins J, Zhang H, Sips HCM, Stam W, Hanegraaf M, Limpens RWAL, Nieuwland R, van Rijn BB, Rabelink TJ, Rensen PCN, den Heijer M, Bijkerk R, van Zonneveld AJ. Estradiol-driven metabolism in transwomen associates with reduced circulating extracellular vesicle microRNA-224/452. Eur J Endocrinol 2021; 185:539-552. [PMID: 34342596 PMCID: PMC8436186 DOI: 10.1530/eje-21-0267] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 08/03/2021] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Sex steroid hormones like estrogens have a key role in the regulation of energy homeostasis and metabolism. In transwomen, gender-affirming hormone therapy like estradiol (in combination with antiandrogenic compounds) could affect metabolism as well. Given that the underlying pathophysiological mechanisms are not fully understood, this study assessed circulating estradiol-driven microRNAs (miRs) in transwomen and their regulation of genes involved in metabolism in mice. METHODS Following plasma miR-sequencing (seq) in a transwomen discovery (n = 20) and validation cohort (n = 30), we identified miR-224 and miR-452. Subsequent systemic silencing of these miRs in male C57Bl/6 J mice (n = 10) was followed by RNA-seq-based gene expression analysis of brown and white adipose tissue in conjunction with mechanistic studies in cultured adipocytes. RESULTS Estradiol in transwomen lowered plasma miR-224 and -452 carried in extracellular vesicles (EVs) while their systemic silencing in mice and cultured adipocytes increased lipogenesis (white adipose) but reduced glucose uptake and mitochondrial respiration (brown adipose). In white and brown adipose tissue, differentially expressed (miR target) genes are associated with lipogenesis (white adipose) and mitochondrial respiration and glucose uptake (brown adipose). CONCLUSION This study identified an estradiol-drive post-transcriptional network that could potentially offer a mechanistic understanding of metabolism following gender-affirming estradiol therapy.
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Affiliation(s)
- Barend W Florijn
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Correspondence should be addressed to B W Florijn;
| | - Jacques M G J Duijs
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Maartje Klaver
- Department of Internal Medicine, Division of Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
| | - Eline N Kuipers
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Department of Internal Medicine (Endocrinology), Leiden University Medical Center, Leiden, The Netherlands
| | - Sander Kooijman
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Department of Internal Medicine (Endocrinology), Leiden University Medical Center, Leiden, The Netherlands
| | - Jurrien Prins
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Huayu Zhang
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Hetty C M Sips
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Department of Internal Medicine (Endocrinology), Leiden University Medical Center, Leiden, The Netherlands
| | - Wendy Stam
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Maaike Hanegraaf
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Ronald W A L Limpens
- Department of Cell and Chemical Biology (Section Electron Microscopy), Leiden University Medical Center, Leiden, The Netherlands
| | - Rienk Nieuwland
- Laboratory of Experimental Clinical Chemistry, Department of Clinical Chemistry and Vesicle Observation Center, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Bas B van Rijn
- Department of Obstetrics and Fetal Medicine, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Ton J Rabelink
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Patrick C N Rensen
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
- Department of Internal Medicine (Endocrinology), Leiden University Medical Center, Leiden, The Netherlands
| | - Martin den Heijer
- Department of Internal Medicine, Division of Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
| | - Roel Bijkerk
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Anton Jan van Zonneveld
- Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
- Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
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Tiwari D, Gupta P. Nuclear Receptors in Asthma: Empowering Classical Molecules Against a Contemporary Ailment. Front Immunol 2021; 11:594433. [PMID: 33574813 PMCID: PMC7870687 DOI: 10.3389/fimmu.2020.594433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 12/09/2020] [Indexed: 02/06/2023] Open
Abstract
The escalation in living standards and adoption of 'Western lifestyle' has an allied effect on the increased allergy and asthma burden in both developed and developing countries. Current scientific reports bespeak an association between allergic diseases and metabolic dysfunction; hinting toward the critical requirement of organized lifestyle and dietary habits. The ubiquitous nuclear receptors (NRs) translate metabolic stimuli into gene regulatory signals, integrating diet inflences to overall developmental and physiological processes. As a consequence of such promising attributes, nuclear receptors have historically been at the cutting edge of pharmacy world. This review discusses the recent findings that feature the cardinal importance of nuclear receptors and how they can be instrumental in modulating current asthma pharmacology. Further, it highlights a possible future employment of therapy involving dietary supplements and synthetic ligands that would engage NRs and aid in eliminating both asthma and linked comorbidities. Therefore, uncovering new and evolving roles through analysis of genomic changes would represent a feasible approach in both prevention and alleviation of asthma.
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Affiliation(s)
| | - Pawan Gupta
- Department of Molecular Biology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
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Abdulrahman AO, Kuerban A, Alshehri ZA, Abdulaal WH, Khan JA, Khan MI. Urolithins Attenuate Multiple Symptoms of Obesity in Rats Fed on a High-Fat Diet. Diabetes Metab Syndr Obes 2020; 13:3337-3348. [PMID: 33061495 PMCID: PMC7524201 DOI: 10.2147/dmso.s268146] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 08/20/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Urolithins are gut microbiota-derived polyphenol metabolites, produced following the consumption of pomegranate, berries, and nuts. Recent studies have shown the potentials of these metabolites on reducing triglycerides accumulation in cultured hepatocytes and adipocytes. In this study, we investigated the ability of both urolithin A (Uro-A) and urolithin B (Uro-B) to attenuate obesity and associated symptoms in a high-fat diet-induced obesity model in rats. METHODS Twenty-four male Wistar rats were randomly assigned to four groups. Group 1 was fed on a normal diet while groups 2, 3, and 4 were fed on a high-fat diet for 10 weeks. After this, groups 3 and 4 were treated with 2.5mg/kg body weight of Uro-A and Uro-B intraperitoneally, respectively. Body weight, serum lipid profile, hepatic antioxidant activity, hepatic lipid accumulation, fecal lipid content, and the expressions of genes involved in lipogenesis and hepatic ER stress were quantified. RESULTS Indeed, a high-fat diet resulted in increased body weight, visceral adipose tissue mass, and oxidative stress in rats. However, treatment with both Uro-A and Uro-B decreased body weight and visceral adipose tissue mass. These metabolites restored hepatic antioxidant capacity and decreased lipid accumulation in addition to an increase in fecal fat excretion. Moreover, both Uro-A and Uro-B treatment downregulated the expression of LXRα and SREBP1c; involved in de novo lipogenesis while upregulating PPARα expression for increased fatty acid oxidation. Furthermore, Uro-A and Uro-B decreased the expression of PERK and IRE1α; which are involved in hepatic ER stress. Taken together, our results showed the potentials of Uro-A and Uro-B in mitigating obesity symptoms and they could thus provide promising roles in the future as functional anti-obesity candidates.
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Affiliation(s)
| | - Abudukadeer Kuerban
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi Arabia
| | - Zuhair Ahmed Alshehri
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi Arabia
| | - Wesam H Abdulaal
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi Arabia
| | - Jalaluddin Awlia Khan
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi Arabia
| | - Mohammad Imran Khan
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi Arabia
- Cancer Metabolism and Epigenetic Unit, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi Arabia
- Correspondence: Mohammad Imran Khan Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah21589, Saudi ArabiaTel +966-12-6952000 Email
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Loss of transglutaminase 2 sensitizes for diet-induced obesity-related inflammation and insulin resistance due to enhanced macrophage c-Src signaling. Cell Death Dis 2019; 10:439. [PMID: 31165747 PMCID: PMC6549190 DOI: 10.1038/s41419-019-1677-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/09/2019] [Accepted: 05/19/2019] [Indexed: 12/11/2022]
Abstract
Transglutaminase 2 (TG2) is a multifunctional protein that promotes clearance of apoptotic cells (efferocytosis) acting as integrin β3 coreceptor. Accumulating evidence indicates that defective efferocytosis contributes to the development of chronic inflammatory diseases. Obesity is characterized by the accumulation of dead adipocytes and inflammatory macrophages in the adipose tissue leading to obesity-related metabolic syndrome. Here, we report that loss of TG2 from bone marrow-derived cells sensitizes for high fat diet (HFD)-induced pathologies. We find that metabolically activated TG2 null macrophages express more phospho-Src and integrin β3, unexpectedly clear dying adipocytes more efficiently via lysosomal exocytosis, but produce more pro-inflammatory cytokines than the wild type ones. Anti-inflammatory treatment with an LXR agonist reverts the HFD-induced phenotype in mice lacking TG2 in bone marrow-derived cells with less hepatic steatosis than in wild type mice proving enhanced lipid clearance. Thus it is interesting to speculate whether LXR agonist treatment together with enhancing lysosomal exocytosis could be a beneficial therapeutic strategy in obesity.
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Small molecules for fat combustion: targeting obesity. Acta Pharm Sin B 2019; 9:220-236. [PMID: 30976490 PMCID: PMC6438825 DOI: 10.1016/j.apsb.2018.09.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 08/01/2018] [Accepted: 08/22/2018] [Indexed: 12/11/2022] Open
Abstract
Obesity is increasing in an alarming rate worldwide, which causes higher risks of some diseases, such as type 2 diabetes, cardiovascular diseases, and cancer. Current therapeutic approaches, either pancreatic lipase inhibitors or appetite suppressors, are generally of limited effectiveness. Brown adipose tissue (BAT) and beige cells dissipate fatty acids as heat to maintain body temperature, termed non-shivering thermogenesis; the activity and mass of BAT and beige cells are negatively correlated with overweight and obesity. The existence of BAT and beige cells in human adults provides an effective weight reduction therapy, a process likely to be amenable to pharmacological intervention. Herein, we combed through the physiology of thermogenesis and the role of BAT and beige cells in combating with obesity. We summarized the thermogenic regulators identified in the past decades, targeting G protein-coupled receptors, transient receptor potential channels, nuclear receptors and miscellaneous pathways. Advances in clinical trials were also presented. The main purpose of this review is to provide a comprehensive and up-to-date knowledge from the biological importance of thermogenesis in energy homeostasis to the representative thermogenic regulators for treating obesity. Thermogenic regulators might have a large potential for further investigations to be developed as lead compounds in fighting obesity.
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Key Words
- AKT, protein kinase B
- ALDH9, aldehyde dehydrogenase 9
- AMPK, AMP-activated protein kinase
- ATP, adenosine triphosphate
- BA, bile acids
- BAT, brown adipose tissue
- BMP8b, bone morphogenetic protein 8b
- Beige cells
- Brown adipose tissue
- C/EBPα, CCAAT/enhancer binding protein α
- CLA, cis-12 conjugated linoleic acid
- CRABP-II, cellular RA binding protein type II
- CRE, cAMP response element
- Cidea, cell death-inducing DNA fragmentation factor α-like effector A
- Dio2, iodothyronine deiodinase type 2
- ERE, estrogen response element
- ERs, estrogen receptors
- FAS, fatty acid synthase
- FGF21, fibroblast growth factor 21
- GPCRs, G protein-coupled receptors
- HFD, high fat diet
- LXR, liver X receptors
- MAPK, mitogen-activated protein kinase
- OXPHOS, oxidative phosphorylation
- Obesity
- PDEs, phosphodiesterases
- PET-CT, positron emission tomography combined with computed tomography
- PGC-1α, peroxisome proliferator-activated receptor γ coactivator 1-α
- PKA, protein kinase A
- PPARs, peroxisome proliferator-activated receptors
- PPREs, peroxisome proliferator response elements
- PRDM16, PR domain containing 16
- PTP1B, protein-tyrosine phosphatase 1B
- PXR, pregnane X receptor
- RA, retinoic acid
- RAR, RA receptor
- RARE, RA response element
- RMR, resting metabolic rate
- RXR, retinoid X receptor
- SIRT1, silent mating type information regulation 2 homolog 1
- SNS, sympathetic nervous system
- TFAM, mitochondrial transcription factor A
- TMEM26, transmembrane protein 26
- TRPs, transient receptor potential cation channels
- Thermogenesis
- UCP1, uncoupling protein 1
- Uncoupling protein 1
- VDR, vitamin D receptor
- VDRE, VDR response elements
- WAT, white adipose tissue
- cAMP, cyclic adenosine monophosphate
- cGMP, cyclic guanosine monophosphate
- β3-AR, β3-adrenergic receptor
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Shang C, Sun W, Wang C, Wang X, Zhu H, Wang L, Yang H, Wang X, Gong F, Pan H. Comparative Proteomic Analysis of Visceral Adipose Tissue in Morbidly Obese and Normal Weight Chinese Women. Int J Endocrinol 2019; 2019:2302753. [PMID: 31929791 PMCID: PMC6935805 DOI: 10.1155/2019/2302753] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/26/2019] [Accepted: 10/01/2019] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE Visceral adipose tissue (VAT) plays a central role in the balance of energy metabolism. The objective of this study was to investigate the differentially expressed proteins in VAT between morbidly obese (BMI >35 kg/m2) and normal weight Chinese women. METHOD Nine morbidly obese women and 8 normal weight women as controls were enrolled. Abdominal VAT was excised and analyzed by label-free one-dimensional liquid chromatography tandem mass spectrometry (1D-LC-MS/MS). Differentially expressed VAT proteins were further analyzed with Gene Ontology (GO) analysis and Ingenuity Pathway Analysis (IPA). Masson's trichrome staining and CD68 immunohistochemical staining of VAT were conducted in all subjects. RESULT A total of 124 differentially expressed proteins were found with a ≥2-fold difference. Forty-one proteins were upregulated, and 83 proteins were downregulated in obese individuals. These altered VAT proteins were involved in the attenuation of the liver X receptor/retinoid X receptor (LXR/RXR) signaling pathway and the activation of the acute-phase response process. Three proteins (ACSL1, HADH, and UCHL1) were validated by western blotting using the same set of VAT samples from 6 morbidly obese and 7 normal weight patients, and the results indicated that the magnitude and direction of the protein changes were in accordance with the proteomic analysis. Masson's trichrome staining and CD68 immunohistochemical staining demonstrated that there was much more collagen fiber deposition and CD68-positive macrophages in the VAT of morbidly obese patients, suggesting extensive fiber deposition and macrophage infiltration. CONCLUSION A number of differentially expressed proteins were identified in VAT between morbidly obese and normal weight Chinese females. These differential proteins could be potential candidates in addressing the role of VAT in the development of obesity.
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Affiliation(s)
- Chen Shang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Wei Sun
- Core Facility of Instrument, Institute of Basic Medicine, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Chunlin Wang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Xiangqing Wang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Huijuan Zhu
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Linjie Wang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Hongbo Yang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Xue Wang
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Fengying Gong
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
| | - Hui Pan
- Key Laboratory of Endocrinology of National Health Commission, Department of Endocrinology, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Peking Union Medical College, Beijing 100730, China
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11
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Knockdown of LXRα Inhibits Goat Intramuscular Preadipocyte Differentiation. Int J Mol Sci 2018; 19:ijms19103037. [PMID: 30301149 PMCID: PMC6213902 DOI: 10.3390/ijms19103037] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 09/21/2018] [Accepted: 09/28/2018] [Indexed: 01/11/2023] Open
Abstract
Goat intramuscular fat (IMF) content is mainly determined by the processes of intramuscular preadipocytes adipogenic differentiation and mature adipocyte lipid accumulation. However, the underlying regulators of these biological processes remain largely unknown. Here, we report that the expression of Liver X receptor alpha (LXRα) reaches a peak at early stage and then gradually decreases during goat intramuscular adipogenesis. Knockdown of LXRα mediated by two independent siRNAs significantly inhibits intramuscular adipocytes lipid accumulation and upregulates preadipocytes marker- preadipocyte factor 1 (pref1) expression. Consistently, siRNA treatments robustly decrease mRNA level of adipogenic related genes, including CCAAT enhancer binding protein alpha (Cebpα), Peroxisome proliferator activated receptor gamma (Pparg), Sterol regulatory element binding protein isoform 1c (Srebp1c), Fatty acids binding protein (aP2) and Lipoprotein lipase (Lpl). Next, adenovirus overexpression of LXRα does not affect intramuscular adipocytes adipogenesis manifested by Oil Red O signal measurement and adipogenic specific genes detection. Mechanically, we found that both CCAAT enhancer binding protein beta (Cebpβ) and Kruppel like factor 8 (Klf8) are potential targets of LXRα, indicated by having putative binding sites of LXRα at the promoter of these genes and similar expression pattern during adipogenesis comparing to LXRα. Importantly, mRNA levels of Cebpβ and Klf8 are downregulated significantly in goat LXRα knockdown intramuscular adipocyte. These results demonstrate that loss function of LXRα inhibits intramuscular adipogenesis possibly through down-regulation of Cebpβ and Klf8. Our research will provide new insights into mechanical regulation of goat IMF deposition.
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12
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Song Z, Xiaoli AM, Yang F. Regulation and Metabolic Significance of De Novo Lipogenesis in Adipose Tissues. Nutrients 2018; 10:nu10101383. [PMID: 30274245 PMCID: PMC6213738 DOI: 10.3390/nu10101383] [Citation(s) in RCA: 237] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 09/20/2018] [Accepted: 09/21/2018] [Indexed: 12/20/2022] Open
Abstract
De novo lipogenesis (DNL) is a complex and highly regulated process in which carbohydrates from circulation are converted into fatty acids that are then used for synthesizing either triglycerides or other lipid molecules. Dysregulation of DNL contributes to human diseases such as obesity, type 2 diabetes, and cardiovascular diseases. Thus, the lipogenic pathway may provide a new therapeutic opportunity for combating various pathological conditions that are associated with dysregulated lipid metabolism. Hepatic DNL has been well documented, but lipogenesis in adipocytes and its contribution to energy homeostasis and insulin sensitivity are less studied. Recent reports have gained significant insights into the signaling pathways that regulate lipogenic transcription factors and the role of DNL in adipose tissues. In this review, we will update the current knowledge of DNL in white and brown adipose tissues with the focus on transcriptional, post-translational, and central regulation of DNL. We will also summarize the recent findings of adipocyte DNL as a source of some signaling molecules that critically regulate energy metabolism.
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Affiliation(s)
- Ziyi Song
- Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Alus M Xiaoli
- Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Fajun Yang
- Departments of Medicine and Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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13
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Cruz MM, Lopes AB, Crisma AR, de Sá RCC, Kuwabara WMT, Curi R, de Andrade PBM, Alonso-Vale MIC. Palmitoleic acid (16:1n7) increases oxygen consumption, fatty acid oxidation and ATP content in white adipocytes. Lipids Health Dis 2018; 17:55. [PMID: 29554895 PMCID: PMC5859716 DOI: 10.1186/s12944-018-0710-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 03/13/2018] [Indexed: 12/27/2022] Open
Abstract
Background We have recently demonstrated that palmitoleic acid (16:1n7) increases lipolysis, glucose uptake and glucose utilization for energy production in white adipose cells. In the present study, we tested the hypothesis that palmitoleic acid modulates bioenergetic activity in white adipocytes. Methods For this, 3 T3-L1 pre-adipocytes were differentiated into mature adipocytes in the presence (or absence) of palmitic (16:0) or palmitoleic (16:1n7) acid at 100 or 200 μM. The following parameters were evaluated: lipolysis, lipogenesis, fatty acid (FA) oxidation, ATP content, oxygen consumption, mitochondrial mass, citrate synthase activity and protein content of mitochondrial oxidative phosphorylation (OXPHOS) complexes. Results Treatment with 16:1n7 during 9 days raised basal and isoproterenol-stimulated lipolysis, FA incorporation into triacylglycerol (TAG), FA oxidation, oxygen consumption, protein expression of subunits representing OXPHOS complex II, III, and V and intracellular ATP content. These effects were not observed in adipocytes treated with 16:0. Conclusions Palmitoleic acid, by concerted action on lipolysis, FA esterification, mitochondrial FA oxidation, oxygen consumption and ATP content, does enhance white adipocyte energy expenditure and may act as local hormone.
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Affiliation(s)
- Maysa M Cruz
- Department of Biological Sciences, Institute of Environmental Sciences, Chemical and Pharmaceutical, Federal University of São Paulo, 210, Sao Nicolau St, Diadema, 09913-030, Brazil
| | - Andressa B Lopes
- Department of Nursing , Health Sciences Center, Federal University of Espírito Santo, Vitória, Brazil
| | - Amanda R Crisma
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Roberta C C de Sá
- Department of Biological Sciences, Institute of Environmental Sciences, Chemical and Pharmaceutical, Federal University of São Paulo, 210, Sao Nicolau St, Diadema, 09913-030, Brazil
| | - Wilson M T Kuwabara
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Interdisciplinary Postgraduate Program in Health Sciences, Institute of Physical Activity Sciences and Sports, Cruzeiro do Sul University, São Paulo, Brazil
| | - Paula B M de Andrade
- Interdisciplinary Postgraduate Program in Health Sciences, Institute of Physical Activity Sciences and Sports, Cruzeiro do Sul University, São Paulo, Brazil
| | - Maria I C Alonso-Vale
- Department of Biological Sciences, Institute of Environmental Sciences, Chemical and Pharmaceutical, Federal University of São Paulo, 210, Sao Nicolau St, Diadema, 09913-030, Brazil.
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14
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Murakami S. The physiological and pathophysiological roles of taurine in adipose tissue in relation to obesity. Life Sci 2017; 186:80-86. [DOI: 10.1016/j.lfs.2017.08.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 07/31/2017] [Accepted: 08/08/2017] [Indexed: 01/08/2023]
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15
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Peng L, Zhao XS, Peng D. Anti-obesity Effect of a Novel Potent Synthetic Steroidal Liver X Receptor α (LXRα)-selective Agonist in Male ob/ob C57BL/6 Mice. INT J PHARMACOL 2017. [DOI: 10.3923/ijp.2017.636.642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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16
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Dong Y, Xu Z, Zhang Z, Yin X, Lin X, Li H, Zheng F. Impaired adipose expansion caused by liver X receptor activation is associated with insulin resistance in mice fed a high-fat diet. J Mol Endocrinol 2017; 58:141-154. [PMID: 28258092 DOI: 10.1530/jme-16-0196] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 01/30/2017] [Indexed: 12/23/2022]
Abstract
Liver X receptors (LXR) are deemed as potential drug targets for atherosclerosis, whereas a role in adipose tissue expansion and its relation to insulin sensitivity remains unclear. To assess the metabolic effects of LXR activation by the dual LXRα/β agonist T0901317, C57BL/6 mice fed a high-fat diet (HFD) were treated with T0901317 (30 mg/kg once daily by intraperitoneal injection) for 3 weeks. Differentiated 3T3-L1 adipocytes were used for analysing the effect of T0901317 on glucose uptake. The following results were obtained from this study. T0901317 reduced fat mass, accompanied by a massive fatty liver and lower serum adipokine levels in HFD mice. Increased adipocyte apoptosis was found in epididymal fat of T0901317-treated HFD mice. In addition, T0901317 treatment promoted basal lipolysis, but blunted the anti-lipolytic action of insulin. Furthermore, LXR activation antagonised PPARγ target genes in epididymal fat and PPARγ-PPRE-binding activity in 3T3-L1 adipocytes. Although the glucose tolerance was comparable to that in HFD mice, the insulin response during IPGTT was significantly higher and the insulin tolerance was significantly impaired in T0901317-treated HFD mice, indicating decreased insulin sensitivity by T0901317 administration, and which was further supported by impaired insulin signalling found in epididymal fat and decreased insulin-induced glucose uptake in 3T3-L1 adipocytes by T0901317 administration. In conclusion, these findings reveal that LXR activation impairs adipose expansion by increasing adipocyte apoptosis, lipolysis and antagonising PPARγ-mediated transcriptional activity, which contributes to decreased insulin sensitivity in whole body. The potential of LXR activation being a therapeutic target for atherosclerosis might be limited by the possibility of exacerbating insulin resistance.
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Affiliation(s)
- Yueting Dong
- Department of EndocrinologySir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Zhiye Xu
- Department of EndocrinologySir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Ziyi Zhang
- Department of EndocrinologySir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Xueyao Yin
- Department of EndocrinologySir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Xihua Lin
- Biomedical Research Center and Key Laboratory of Biotherapy of Zhejiang ProvinceSir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Hong Li
- Department of EndocrinologySir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Fenping Zheng
- Department of EndocrinologySir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
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17
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Guillemot-Legris O, Mutemberezi V, Muccioli GG. Oxysterols in Metabolic Syndrome: From Bystander Molecules to Bioactive Lipids. Trends Mol Med 2016; 22:594-614. [PMID: 27286741 DOI: 10.1016/j.molmed.2016.05.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/12/2016] [Accepted: 05/13/2016] [Indexed: 12/11/2022]
Abstract
Oxysterols are cholesterol metabolites now considered bona fide bioactive lipids. Recent studies have identified new receptors for oxysterols involved in immune and inflammatory processes, hence reviving their appeal. Through multiple receptors, oxysterols are involved in numerous metabolic and inflammatory processes, thus emerging as key mediators in metabolic syndrome. This syndrome is characterized by complex interactions between inflammation and a dysregulated metabolism. Presently, the use of synthetic ligands and genetic models has facilitated a better understanding of the roles of oxysterols in metabolism, but also raised interesting questions. We discuss recent findings on the absolute levels of oxysterols in tissues, their newly identified targets, and the mechanistic studies emphasizing their importance in metabolic disease, as there is a pressing need to further comprehend these intriguing bioactive lipids.
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Affiliation(s)
- Owein Guillemot-Legris
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, Av. E.Mounier, 72 (B1.72.01), 1200 Bruxelles, Belgium
| | - Valentin Mutemberezi
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, Av. E.Mounier, 72 (B1.72.01), 1200 Bruxelles, Belgium
| | - Giulio G Muccioli
- Bioanalysis and Pharmacology of Bioactive Lipids Research Group, Louvain Drug Research Institute, Université catholique de Louvain, Av. E.Mounier, 72 (B1.72.01), 1200 Bruxelles, Belgium.
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18
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Liu D, Bordicchia M, Zhang C, Fang H, Wei W, Li JL, Guilherme A, Guntur K, Czech MP, Collins S. Activation of mTORC1 is essential for β-adrenergic stimulation of adipose browning. J Clin Invest 2016; 126:1704-16. [PMID: 27018708 DOI: 10.1172/jci83532] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 02/19/2016] [Indexed: 12/27/2022] Open
Abstract
A classic metabolic concept posits that insulin promotes energy storage and adipose expansion, while catecholamines stimulate release of adipose energy stores by hydrolysis of triglycerides through β-adrenergic receptor (βARs) and protein kinase A (PKA) signaling. Here, we have shown that a key hub in the insulin signaling pathway, activation of p70 ribosomal S6 kinase (S6K1) through mTORC1, is also triggered by PKA activation in both mouse and human adipocytes. Mice with mTORC1 impairment, either through adipocyte-specific deletion of Raptor or pharmacologic rapamycin treatment, were refractory to the well-known βAR-dependent increase of uncoupling protein UCP1 expression and expansion of beige/brite adipocytes (so-called browning) in white adipose tissue (WAT). Mechanistically, PKA directly phosphorylated mTOR and RAPTOR on unique serine residues, an effect that was independent of insulin/AKT signaling. Abrogation of the PKA site within RAPTOR disrupted βAR/mTORC1 activation of S6K1 without affecting mTORC1 activation by insulin. Conversely, a phosphomimetic RAPTOR augmented S6K1 activity. Together, these studies reveal a signaling pathway from βARs and PKA through mTORC1 that is required for adipose browning by catecholamines and provides potential therapeutic strategies to enhance energy expenditure and combat metabolic disease.
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MESH Headings
- 3T3-L1 Cells
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Adipose Tissue, Brown/cytology
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, White/cytology
- Adipose Tissue, White/metabolism
- Animals
- Cyclic AMP-Dependent Protein Kinases/genetics
- Cyclic AMP-Dependent Protein Kinases/metabolism
- HEK293 Cells
- Humans
- Insulin/genetics
- Insulin/metabolism
- Mechanistic Target of Rapamycin Complex 1
- Mice
- Mice, Knockout
- Multiprotein Complexes/genetics
- Multiprotein Complexes/metabolism
- Receptors, Adrenergic, beta/genetics
- Regulatory-Associated Protein of mTOR
- Ribosomal Protein S6 Kinases, 70-kDa/genetics
- Ribosomal Protein S6 Kinases, 70-kDa/metabolism
- Ribosomal Protein S6 Kinases, 90-kDa/genetics
- Ribosomal Protein S6 Kinases, 90-kDa/metabolism
- Signal Transduction/physiology
- TOR Serine-Threonine Kinases/genetics
- TOR Serine-Threonine Kinases/metabolism
- Uncoupling Protein 1/biosynthesis
- Uncoupling Protein 1/genetics
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19
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Korach-André M, Gustafsson JÅ. Liver X receptors as regulators of metabolism. Biomol Concepts 2016; 6:177-90. [PMID: 25945723 DOI: 10.1515/bmc-2015-0007] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/01/2015] [Indexed: 11/15/2022] Open
Abstract
The liver X receptors (LXR) are crucial regulators of metabolism. After ligand binding, they regulate gene transcription and thereby mediate changes in metabolic pathways. Modulation of LXR and their downstream targets has appeared to be a promising treatment for metabolic diseases especially atherosclerosis and cholesterol metabolism. However, the complexity of LXR action in various metabolic tissues and the liver side effect of LXR activation have slowed down the interest for LXR drugs. In this review, we summarized the role of LXR in the main metabolically active tissues with a special focus on obesity and associated diseases in mammals. We will also discuss the dual interplay between the two LXR isoforms suggesting that they may collaborate to establish a fine and efficient system for the maintenance of metabolism homeostasis.
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20
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Lin JC. Impacts of Alternative Splicing Events on the Differentiation of Adipocytes. Int J Mol Sci 2015; 16:22169-89. [PMID: 26389882 PMCID: PMC4613302 DOI: 10.3390/ijms160922169] [Citation(s) in RCA: 18] [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: 08/13/2015] [Revised: 09/07/2015] [Accepted: 09/07/2015] [Indexed: 02/07/2023] Open
Abstract
Alternative splicing was found to be a common phenomenon after the advent of whole transcriptome analyses or next generation sequencing. Over 90% of human genes were demonstrated to undergo at least one alternative splicing event. Alternative splicing is an effective mechanism to spatiotemporally expand protein diversity, which influences the cell fate and tissue development. The first focus of this review is to highlight recent studies, which demonstrated effects of alternative splicing on the differentiation of adipocytes. Moreover, use of evolving high-throughput approaches, such as transcriptome analyses (RNA sequencing), to profile adipogenic transcriptomes, is also addressed.
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Affiliation(s)
- Jung-Chun Lin
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, 250 Wu-Hsing Street, Taipei 11031, Taiwan.
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21
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Qiushi W, Guanghua L, Guangquan X. Acanthoic acid ameliorates lipopolysaccharide-induced acute lung injury. Eur J Pharmacol 2015; 750:32-8. [PMID: 25620130 DOI: 10.1016/j.ejphar.2015.01.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 01/13/2015] [Accepted: 01/15/2015] [Indexed: 12/20/2022]
Abstract
Acanthoic acid, a pimaradiene diterpene isolated from Acanthopanax koreanum, has been reported to have anti-inflammatory activities. However, the effects of acanthoic acid on LPS-induced acute lung injury have not been reported. The purpose of this study was to investigate the protective effect of acanthoic acid on LPS-induced ALI and to clarify the possible anti-inflammatory mechanisms. In vivo, an LPS-induced ALI model in mice was used to assess the protective effects of acanthoic acid on ALI. Meanwhile, mouse alveolar macrophages MH-S were stimulated with LPS in the presence or absence of acanthoic acid. The expressions of TNF-α, IL-6 and IL-1β were measured by ELISA. LXRα and NF-κB expression were detected by Western blot analysis. The results showed that acanthoic acid downregulated LPS-induced TNF-α, IL-6 and IL-1β production in BALF. MPO activity and lung wet-to-dry ratio were also inhibited by acanthoic acid. In addition, acanthoic acid attenuated lung histopathologic changes. In vitro, acanthoic acid inhibited inflammatory cytokines TNF-α, IL-6 and IL-1β production and NF-κB activation in LPS-stimulated alveolar macrophages. Acanthoic acid was found to up-regulated the expression of LXRα. The inhibition of acanthoic acid on LPS-induced cytokines and NF-κB activation can be abolished by LXRα siRNA. In conclusion, our results suggested that the protective effect of acanthoic acid on LPS-induced ALI was due to its ability to activate LXRα, thereby inhibiting LPS-induced inflammatory response.
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Affiliation(s)
- Wang Qiushi
- Department of Thoracic Surgery, The 2nd Affiliated Hospital of Harbin Medical University, Harbin 150086, China
| | - Li Guanghua
- Department of Thoracic Surgery, The 2nd Affiliated Hospital of Harbin Medical University, Harbin 150086, China
| | - Xu Guangquan
- Department of Thoracic Surgery, The 2nd Affiliated Hospital of Harbin Medical University, Harbin 150086, China.
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22
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Ma A, Wang Y, Zhang Q. Tormentic acid reduces inflammation in BV-2 microglia by activating the liver X receptor alpha. Neuroscience 2014; 287:9-14. [PMID: 25497374 DOI: 10.1016/j.neuroscience.2014.12.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 12/03/2014] [Accepted: 12/03/2014] [Indexed: 01/18/2023]
Abstract
Tormentic acid (TA) has been reported to have anticancer, anti-inflammatory and anti-atherogenic properties. However, the effects of TA on neuroinflammation have not been reported. In this study, we investigated whether TA inhibited lipopolysaccharide (LPS)-induced inflammatory response in BV2 microglia cells. BV2 microglia cells were treated with TA for 1h before exposure to LPS. The expression of inducible nitric oxide synthase (iNOS), Cyclooxygenase-2 (COX-2), Nuclear factor κB (NF-κB) and liver X receptor alpha (LXRα) was detected by western blotting. The expression of cytokines Tumor necrosis factor-alpha (TNF-α) and interleukin 1beta (IL-1β) was detected by enzyme-linked immunosorbent assays (ELISA). Results showed that TA inhibited nitric oxide (NO), prostaglandin E2 (PGE2) production by inhibiting iNOS and COX-2 expression. TA also inhibited LPS-induced inflammatory cytokines TNF-α and IL-1β expression. Furthermore, TA could activate LXRα and inhibit LPS-induced NF-κB activation. Knowdown of LXRα reversed the anti-inflammatory effects of TA. In conclusion, our results indicate that TA exerts an anti-inflammatory effect on LPS-stimulated BV2 microglia cells by activating LXRα.
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Affiliation(s)
- A Ma
- Department of Neurology, He Bei Provincial Chest Hospital, Shi Jiazhuang 050000, China
| | - Y Wang
- Department of Nephrology, He Bei Provincial Chest Hospital, Shi Jiazhuang 050000, China
| | - Q Zhang
- Department of Neurology, He Bei Provincial Chest Hospital, Shi Jiazhuang 050000, China.
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23
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Hijmans BS, Tiemann CA, Grefhorst A, Boesjes M, van Dijk TH, Tietge UJF, Kuipers F, van Riel NAW, Groen AK, Oosterveer MH. A systems biology approach reveals the physiological origin of hepatic steatosis induced by liver X receptor activation. FASEB J 2014; 29:1153-64. [PMID: 25477282 DOI: 10.1096/fj.14-254656] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 11/05/2014] [Indexed: 12/12/2022]
Abstract
Liver X receptor (LXR) agonists exert potent antiatherosclerotic actions but simultaneously induce excessive triglyceride (TG) accumulation in the liver. To obtain a detailed insight into the underlying mechanism of hepatic TG accumulation, we used a novel computational modeling approach called analysis of dynamic adaptations in parameter trajectories (ADAPT). We revealed that both input and output fluxes to hepatic TG content are considerably induced on LXR activation and that in the early phase of LXR agonism, hepatic steatosis results from only a minor imbalance between the two. It is generally believed that LXR-induced hepatic steatosis results from increased de novo lipogenesis (DNL). In contrast, ADAPT predicted that the hepatic influx of free fatty acids is the major contributor to hepatic TG accumulation in the early phase of LXR activation. Qualitative validation of this prediction showed a 5-fold increase in the contribution of plasma palmitate to hepatic monounsaturated fatty acids on acute LXR activation, whereas DNL was not yet significantly increased. This study illustrates that complex effects of pharmacological intervention can be translated into distinct patterns of metabolic regulation through state-of-the-art mathematical modeling.
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Affiliation(s)
- Brenda S Hijmans
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Christian A Tiemann
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Aldo Grefhorst
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Marije Boesjes
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Theo H van Dijk
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Uwe J F Tietge
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Folkert Kuipers
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Natal A W van Riel
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Albert K Groen
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
| | - Maaike H Oosterveer
- Departments of *Pediatrics and Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Netherlands Consortium for Systems Biology, University of Amsterdam, Amsterdam, The Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands; and Groningen Centre for Systems Biology, University of Groningen, Groningen, The Netherlands
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Zheng F, Zhang S, Lu W, Wu F, Yin X, Yu D, Pan Q, Li H. Regulation of insulin resistance and adiponectin signaling in adipose tissue by liver X receptor activation highlights a cross-talk with PPARγ. PLoS One 2014; 9:e101269. [PMID: 24972069 PMCID: PMC4074121 DOI: 10.1371/journal.pone.0101269] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 06/05/2014] [Indexed: 01/15/2023] Open
Abstract
Liver X receptors (LXRs) have been recognized as a promising therapeutic target for atherosclerosis; however, their role in insulin sensitivity is controversial. Adiponectin plays a unique role in maintaining insulin sensitivity. Currently, no systematic experiments elucidating the role of LXR activation in insulin function based on adiponectin signaling have been reported. Here, we investigated the role of LXR activation in insulin resistance based on adiponectin signaling, and possible mechanisms. C57BL/6 mice maintained on a regular chow received the LXR agonist, T0901317 (30 mg/kg.d) for 3 weeks by intraperitoneal injection, and differentiated 3T3-L1 adipocytes were treated with T0901317 or GW3965. T0901317 treatment induced significant insulin resistance in C57BL/6 mice. It decreased adiponectin gene transcription in epididymal fat, as well as serum adiponectin levels. Activity of AMPK, a key mediator of adiponectin signaling, was also decreased, resulting in decreased Glut-4 membrane translocation in epididymal fat. In contrast, adiponectin activity was not changed in the liver of T0901317 treated mice. In vitro, both T0901317 and GW3965 decreased adiponectin expression in adipocytes in a dose-dependent manner, an effect which was diminished by LXRα silencing. ChIP-qPCR studies demonstrated that T0901317 decreased the binding of PPARγ to the PPAR-responsive element (PPRE) of the adiponectin promoter in a dose-dependent manner. Furthermore, T0901317 exerted an antagonistic effect on the expression of adiponectin in adipocytes co-treated with 3 µM Pioglitazone. In luciferase reporter gene assays, T0901317 dose-dependently inhibited PPRE-Luc activity in HEK293 cells co-transfected with LXRα and PPARγ. These results suggest that LXR activation induces insulin resistance with decreased adiponectin signaling in epididymal fat, probably due to negative regulation of PPARγ signaling. These findings indicate that the potential of LXR activation as a therapeutic target for atherosclerosis may be limited by the possibility of exacerbating insulin resistance-related disease.
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Affiliation(s)
- Fenping Zheng
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
| | - Saifei Zhang
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
| | - Weina Lu
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
| | - Fang Wu
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
| | - Xueyao Yin
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
| | - Dan Yu
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
| | - Qianqian Pan
- Biomedical Research Center and Key Laboratory of Biotherapy of Zhejiang Province, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P.R. China
| | - Hong Li
- Department of Endocrinology, Sir Run Run Shaw Hospital Affiliated with School of Zhejiang University, Hangzhou, Zhejiang, P. R. China
- * E-mail:
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