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Terra M, García-Arévalo M, Avelino T, Degaki K, Malospirito C, de Carvalho M, Torres F, Saito Â, Figueira A. AM-879, a PPARy non-agonist and Ser273 phosphorylation blocker, promotes insulin sensitivity without adverse effects in mice. Metabol Open 2022; 17:100221. [PMID: 36588655 PMCID: PMC9800205 DOI: 10.1016/j.metop.2022.100221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 12/02/2022] [Accepted: 12/09/2022] [Indexed: 12/25/2022] Open
Abstract
Obesity is one of the main risk factors for type 2 diabetes, and peroxisome proliferator-activated receptor γ (PPARγ) is considered a promising pathway on insulin sensitivity and adipose tissue metabolism. The search for molecules acting as insulin sensitizers have increased, especially for molecules that block PPARγ-Ser273 phosphorylation, without reaching full agonism. We evaluated the in vivo effects of AM-879, a PPARγ non-agonist, and found that AM-879 exerts different effects in mice depending on the dose. At lower doses, this ligand decreased BAT, increased leptin and Crh expression. However, at a higher dose, it promoted improvement on insulin sensitivity, ameliorates expression of metabolism-related genes, decreased the expression of genes related to liver toxicity, maintaining body weight and adipocyte size. These results present a new lead molecule to ameliorates insulin resistance and confirm AM-879 as a PPARγ non-agonist which blocks Ser273 phosphorylation as a good strategy to modulate insulin sensitivity without developing the adverse effects promoted by PPARγ full agonists.
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Affiliation(s)
- M.F. Terra
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil,Post Graduate Program in Functional and Molecular Biology, Institute of Biology, State University of Campinas (Unicamp), Campinas, Brazil
| | - M. García-Arévalo
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - T.M. Avelino
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil,Post Graduate Program in Pharmacological Science, State University of Campinas (Unicamp), Campinas, Brazil
| | - K.Y. Degaki
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - C.C. Malospirito
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil,Post Graduate Program in Functional and Molecular Biology, Institute of Biology, State University of Campinas (Unicamp), Campinas, Brazil
| | - M. de Carvalho
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil,Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - F.R. Torres
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - Â. Saito
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil
| | - A.C.M. Figueira
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, Brazil,Corresponding author.
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Zhang L, Zhang J, Liu Y, Zhang P, Nie J, Zhao R, Shi Q, Sun H, Jiao D, Chen Y, Zhao X, Huang Y, Li Y, Zhao JY, Xu W, Zhao SM, Wang C. Mitochondrial STAT5A promotes metabolic remodeling and the Warburg effect by inactivating the pyruvate dehydrogenase complex. Cell Death Dis 2021; 12:634. [PMID: 34148062 PMCID: PMC8214628 DOI: 10.1038/s41419-021-03908-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 05/31/2021] [Accepted: 06/07/2021] [Indexed: 12/12/2022]
Abstract
Signal transducer and activator 5a (STAT5A) is a classical transcription factor that plays pivotal roles in various biological processes, including tumor initiation and progression. A fraction of STAT5A is localized in the mitochondria, but the biological functions of mitochondrial STAT5A remain obscure. Here, we show that STAT5A interacts with pyruvate dehydrogenase complex (PDC), a mitochondrial gatekeeper enzyme connecting two key metabolic pathways, glycolysis and the tricarboxylic acid cycle. Mitochondrial STAT5A disrupts PDC integrity, thereby inhibiting PDC activity and remodeling cellular glycolysis and oxidative phosphorylation. Mitochondrial translocation of STAT5A is increased under hypoxic conditions. This strengthens the Warburg effect in cancer cells and promotes in vitro cell growth under hypoxia and in vivo tumor growth. Our findings indicate distinct pro-oncogenic roles of STAT5A in energy metabolism, which is different from its classical function as a transcription factor.
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Affiliation(s)
- Liang Zhang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Jianong Zhang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yan Liu
- Institute of metabolism and integrative biology (IMIB), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Pingzhao Zhang
- Fudan University Shanghai Cancer Center and Department of Pathology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, 200032, Shanghai, China
| | - Ji Nie
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Rui Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Qin Shi
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Huiru Sun
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Dongyue Jiao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yingji Chen
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Xiaying Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yan Huang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Yao Li
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Jian-Yuan Zhao
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 200438, Shanghai, China
| | - Wei Xu
- Shanghai Fifth People's Hospital and Institutes of Biomedical Sciences, Fudan University, 20032, Shanghai, China
| | - Shi-Min Zhao
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China.
| | - Chenji Wang
- Obstetrics & Gynecology Hospital of Fudan University, State Key Laboratory of Genetic Engineering, MOE Engineering Research Center of Gene Technology, Key Laboratory of Reproduction Regulation of NPFPC (SIPPR, IRD), School of Life Sciences, Fudan University, 200438, Shanghai, China.
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Bogie KM, Schwartz K, Li Y, Wang S, Dai W, Sun J. Exploring adipogenic and myogenic circulatory biomarkers of recurrent pressure injury risk for persons with spinal cord injury. J Circ Biomark 2020; 9:1-7. [PMID: 33599626 PMCID: PMC7883629 DOI: 10.33393/jcb.2020.2121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 08/18/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose: To investigate linkages between circulatory adipogenic and myogenic biomarkers, gluteal intramuscular adipose tissue (IMAT), and pressure injury (PrI) history following spinal cord injury (SCI). Methods: This is an observational repeated-measures study of 30 individuals with SCI. Whole blood was collected regularly over 2-3 years. Circulatory adipogenic and myogenic gene expression was determined. IMAT was defined as above/below 15% (IMATd) or percentage (IMAT%). PrI history was defined as recurrent PrI (RPrI) or PrI number (n PrI). Model development used R packages (version 3.5.1). Univariate analysis screened for discriminating genes for downstream multivariate and combined models of averaged and longitudinal data for binary (RPrI/IMATd) and finer scales (n PrI/IMAT%). Results: For adipogenesis, Krüppel-like factor 4 was the top RPrI predictor together with resistin and cyclin D1, and sirtuin 2 was the top IMAT predictor. For myogenesis, the top RPrI predictor was dysferlin 2B, and pyruvate dehydrogenase kinase-4 was the top IMAT predictor together with dystrophin. Conclusion: Circulatory adipogenic and myogenic biomarkers have statistically significant relationships with PrI history and IMAT for persons with SCI. Biomarkers of interest may act synergistically or additively. Variable importance rankings can reveal nonlinear correlations among the predictors. Biomarkers of interest may act synergistically or additively, thus multiple genes may need to be included for prediction with finer distinction.
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Affiliation(s)
- Kath M. Bogie
- Case Western Reserve University, Departments of Orthopaedics and Biomedical Engineering, Cleveland, Ohio - USA
- Louis Stokes Cleveland Veterans Affairs Medical Center (LSCVAMC), Research Service, Cleveland, Ohio - USA
| | - Katelyn Schwartz
- Louis Stokes Cleveland Veterans Affairs Medical Center (LSCVAMC), Research Service, Cleveland, Ohio - USA
| | - Youjin Li
- Case Western Reserve University, Department of Population & Quantitative Health Sciences, Cleveland, Ohio - USA
| | - Shengxuan Wang
- Case Western Reserve University, Department of Population & Quantitative Health Sciences, Cleveland, Ohio - USA
| | - Wei Dai
- Case Western Reserve University, Department of Population & Quantitative Health Sciences, Cleveland, Ohio - USA
| | - Jiayang Sun
- Department of Statistics, George Mason University, Fairfax, Virginia - USA
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Fernández-Calleja JMS, Bouwman LMS, Swarts HJM, Oosting A, Keijer J, van Schothorst EM. Direct and Long-Term Metabolic Consequences of Lowly vs. Highly-Digestible Starch in the Early Post-Weaning Diet of Mice. Nutrients 2018; 10:E1788. [PMID: 30453616 PMCID: PMC6265974 DOI: 10.3390/nu10111788] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 11/09/2018] [Accepted: 11/14/2018] [Indexed: 01/26/2023] Open
Abstract
Starches of low and high digestibility have different metabolic effects. Here, we examined whether this gives differential metabolic programming when fed in the immediate post-weaning period. Chow-fed mice were time-mated, and their nests were standardized and cross-fostered at postnatal days 1⁻2. After postnatal week (PW) 3, individually housed female and male offspring were switched to a lowly-digestible (LDD) or highly-digestible starch diet (HDD) for three weeks. All of the mice received the same high-fat diet (HFD) for nine weeks thereafter. Energy and substrate metabolism and carbohydrate fermentation were studied at the end of the HDD/LDD and HFD periods by extended indirect calorimetry. Glucose tolerance (PW 11) and metabolic flexibility (PW14) were analyzed. Directly in response to the LDD versus the HDD, females showed smaller adipocytes with less crown-like structures in gonadal white adipose tissue, while males had a lower fat mass and higher whole body fat oxidation levels. Both LDD-fed females and males showed an enlarged intestinal tract. Although most of the phenotypical differences disappeared in adulthood in both sexes, females exposed to LDD versus HDD in the early post-weaning period showed improved metabolic flexibility in adulthood. Cumulatively, these results suggest that the type of starch introduced after weaning could, at least in females, program later-life health.
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Affiliation(s)
| | - Lianne M S Bouwman
- Human and Animal Physiology, Wageningen University, De Elst 1, Wageningen 6708 WD, The Netherlands.
| | - Hans J M Swarts
- Human and Animal Physiology, Wageningen University, De Elst 1, Wageningen 6708 WD, The Netherlands.
| | - Annemarie Oosting
- Danone Nutricia Research, Uppsalalaan 12, Utrecht 3584 CT, The Netherlands.
| | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, De Elst 1, Wageningen 6708 WD, The Netherlands.
| | - Evert M van Schothorst
- Human and Animal Physiology, Wageningen University, De Elst 1, Wageningen 6708 WD, The Netherlands.
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Segovia SA, Vickers MH, Gray C, Zhang XD, Reynolds CM. Conjugated Linoleic Acid Supplementation Improves Maternal High Fat Diet-Induced Programming of Metabolic Dysfunction in Adult Male Rat Offspring. Sci Rep 2017; 7:6663. [PMID: 28751679 PMCID: PMC5532367 DOI: 10.1038/s41598-017-07108-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 06/23/2017] [Indexed: 12/13/2022] Open
Abstract
The developmental origins of health and disease hypothesis proposes that an adverse early life environment, including in utero exposure to a maternal obesogenic environment, can lead to an increased long-term risk of obesity and related metabolic complications in offspring. We assessed whether maternal supplementation with conjugated linoleic acid (CLA) could prevent some of these adverse effects in offspring exposed to a maternal high fat diet. Sprague-Dawley dams consumed either a: control (CD), control with CLA (CLA), high fat (HF) or high fat with CLA (HFCLA) diet 10 days prior to mating and throughout pregnancy/lactation. Male offspring were weaned onto a standard chow diet. Body composition was quantified by DXA and oral glucose tolerance tests conducted on adult offspring. Gene/protein expression and histological analysis were conducted in adipose tissue. Offspring from HF dams had increased body weight, body fat deposition, impaired insulin sensitivity and adipocyte hypertrophy; all of which were rescued in HFCLA offspring. Molecular and histological analyses of the adipose tissue suggest that disturbances in adipogenesis may mediate the metabolic dysfunction observed in HF offspring. Therefore, CLA supplementation to a maternal obesogenic diet may be a promising strategy to prevent adverse programming outcomes.
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Affiliation(s)
| | - Mark H Vickers
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - Clint Gray
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - Xiaoyuan D Zhang
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - Clare M Reynolds
- Liggins Institute, University of Auckland, Auckland, New Zealand.
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Zhang W, Zhang SL, Hu X, Tam KY. Targeting Tumor Metabolism for Cancer Treatment: Is Pyruvate Dehydrogenase Kinases (PDKs) a Viable Anticancer Target? Int J Biol Sci 2015; 11:1390-400. [PMID: 26681918 PMCID: PMC4671996 DOI: 10.7150/ijbs.13325] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/07/2015] [Indexed: 01/07/2023] Open
Abstract
Cancer remains a lethal threat to global lives. Development of novel anticancer therapeutics is still a challenge to scientists in the field of biomedicine. In cancer cells, the metabolic features are significantly different from those of normal ones, which are hallmarks of several malignancies. Recent studies brought atypical cellular metabolism, such as aerobic glycolysis or the Warburg effect, into the scientific limelight. Targeting these altered metabolic pathways in cancer cells presents a promising therapeutic strategy. Pyruvate dehydrogenase kinases (PDKs), key enzymes in the pathway of glucose metabolism, could inactivate the pyruvate dehydrogenase complex (PDC) by phosphorylating it and preserving the substrates pyruvate, lactate and alanine for gluconeogenesis. Overexpression of PDKs could block the oxidative decarboxylation of pyruvate to satisfy high oxygen demand in cancer cells, while inhibition of PDKs could upregulate the activity of PDC and rectify the balance between the demand and supply of oxygen, which could lead to cancer cell death. Thus, inhibitors targeting PDKs represent a promising strategy for cancer treatment by acting on glycolytic tumors while showing minimal side effects on the oxidative healthy organs. This review considers the role of PDKs as regulator of PDC that catalyzes the oxidative decarboxylation of pyruvate in mitochondrion. It is concluded that PDKs are solid therapeutic targets. Inhibition of PDKs could be an attractive therapeutic approach for the development of anti-cancer drugs.
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Affiliation(s)
- Wen Zhang
- Drug Development Core, Faculty of Health Sciences, University of Macau, Macau, China
| | - Shao-Lin Zhang
- Drug Development Core, Faculty of Health Sciences, University of Macau, Macau, China
| | - Xiaohui Hu
- Drug Development Core, Faculty of Health Sciences, University of Macau, Macau, China
| | - Kin Yip Tam
- Drug Development Core, Faculty of Health Sciences, University of Macau, Macau, China
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Nugara RN, Inafuku M, Takara K, Iwasaki H, Oku H. Pteryxin: A coumarin in Peucedanum japonicum Thunb leaves exerts antiobesity activity through modulation of adipogenic gene network. Nutrition 2014; 30:1177-84. [DOI: 10.1016/j.nut.2014.01.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/27/2013] [Accepted: 01/20/2014] [Indexed: 10/25/2022]
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Zhang S, Hulver MW, McMillan RP, Cline MA, Gilbert ER. The pivotal role of pyruvate dehydrogenase kinases in metabolic flexibility. Nutr Metab (Lond) 2014; 11:10. [PMID: 24520982 PMCID: PMC3925357 DOI: 10.1186/1743-7075-11-10] [Citation(s) in RCA: 309] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 02/08/2014] [Indexed: 01/26/2023] Open
Abstract
Metabolic flexibility is the capacity of a system to adjust fuel (primarily glucose and fatty acids) oxidation based on nutrient availability. The ability to alter substrate oxidation in response to nutritional state depends on the genetically influenced balance between oxidation and storage capacities. Competition between fatty acids and glucose for oxidation occurs at the level of the pyruvate dehydrogenase complex (PDC). The PDC is normally active in most tissues in the fed state, and suppressing PDC activity by pyruvate dehydrogenase (PDH) kinase (PDK) is crucial to maintain energy homeostasis under some extreme nutritional conditions in mammals. Conversely, inappropriate suppression of PDC activity might promote the development of metabolic diseases. This review summarizes PDKs’ pivotal role in control of metabolic flexibility under various nutrient conditions and in different tissues, with emphasis on the best characterized PDK4. Understanding the regulation of PDC and PDKs and their roles in energy homeostasis could be beneficial to alleviate metabolic inflexibility and to provide possible therapies for metabolic diseases, including type 2 diabetes (T2D).
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Affiliation(s)
| | | | | | | | - Elizabeth R Gilbert
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA USA.
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Wan Z, Matravadia S, Holloway GP, Wright DC. FAT/CD36 regulates PEPCK expression in adipose tissue. Am J Physiol Cell Physiol 2013; 304:C478-84. [PMID: 23302781 DOI: 10.1152/ajpcell.00372.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fatty acid translocase (FAT)/CD36 has been extensively studied for its role in facilitating fatty acid uptake. Recent findings have also demonstrated that this protein regulates adipocyte lipolysis and may modulate fatty acid reesterification. As FAT/CD36 has been shown to control the expression of genes involved in fatty acid oxidation in adipocytes, we reasoned that this protein might also control the expression of enzymes involved in fatty acid reesterification. In adipose tissue from FAT/CD36 knockout (KO) mice, we found that glycerol and fatty acid release were reduced and this was associated with reductions in adipose triglyceride lipase. Decreases in lipolysis were paralleled by increases in the free fatty acid-to-glycerol ratio and reductions in primary and fractional rates of fatty acid reesterfication in cultured adipose tissue from FAT/CD36 KO mice. Reductions in reesterfication were associated with decreases in the mRNA expression and protein content of phosphoenolpyruvate carboxykinase (PEPCK). To determine if reductions in lipolysis could lead to decreases in PEPCK mRNA expression, we treated cultured mouse adipose tissue with the lipase inhibitor CAY10499 (2 μM) and found that this resulted in an ∼50% reduction in PEPCK mRNA expression. Treatment with hexarelin (10 μM, 12 h), a CD36 agonist, increased PEPCK mRNA expression independent of lipolysis. Collectively, our results provide novel evidence that FAT/CD36 regulates PEPCK in adipose tissue and that this could be secondary to reductions in lipolysis.
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Affiliation(s)
- Zhongxiao Wan
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta, Canada
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