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Li S, Wang M, Ma J, Pang X, Yuan J, Pan Y, Fu Y, Laher I. MOTS-c and Exercise Restore Cardiac Function by Activating of NRG1-ErbB Signaling in Diabetic Rats. Front Endocrinol (Lausanne) 2022; 13:812032. [PMID: 35370955 PMCID: PMC8969227 DOI: 10.3389/fendo.2022.812032] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 02/16/2022] [Indexed: 12/13/2022] Open
Abstract
Pathologic cardiac remodeling and dysfunction are the most common complications of type 2 diabetes. Physical exercise is important in inhibiting myocardial pathologic remodeling and restoring cardiac function in diabetes. The mitochondrial-derived peptide MOTS-c has exercise-like effects by improving insulin resistance, combatting hyperglycemia, and reducing lipid accumulation. We investigated the effects and transcriptomic profiling of MOTS-c and aerobic exercise on cardiac properties in a rat model of type 2 diabetes which was induced by feeding a high fat high sugar diet combined with an injection of a low dose of streptozotocin. Both aerobic exercise and MOTS-c treatment reduced abnormalities in cardiac structure and function. Transcriptomic function enrichment analysis revealed that MOTS-c had exercise-like effects on inflammation, myocardial apoptosis, angiogenesis and endothelial cell proliferation and migration, and showed that the NRG1-ErbB4 pathway might be an important component in both MOTS-c and exercise induced attenuation of cardiac dysfunction in diabetes. Moreover, our findings suggest that MOTS-c activates NRG1-ErbB4 signaling and mimics exercise-induced cardio-protection in diabetes.
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Affiliation(s)
- Shunchang Li
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Manda Wang
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Jiacheng Ma
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Xiaoli Pang
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Jinghan Yuan
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Yanrong Pan
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Yu Fu
- Institute of Sports Medicine and Health, Chengdu Sport University, Chengdu, China
| | - Ismail Laher
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
- *Correspondence: Ismail Laher,
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2
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Ceccarelli G, Benedetti L, Arcari ML, Carubbi C, Galli D. Muscle Stem Cell and Physical Activity: What Point is the Debate at? Open Med (Wars) 2017; 12:144-156. [PMID: 28765836 PMCID: PMC5529938 DOI: 10.1515/med-2017-0022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 04/21/2017] [Indexed: 12/11/2022] Open
Abstract
In the last 15 years, it emerged that the practice of regular physical activity reduces the risks of many diseases (cardiovascular diseases, diabetes, etc.) and it is fundamental in weight control and energy consuming to contrast obesity. Different groups proposed many molecular mechanisms as responsible for the positive effects of physical activity in healthy life. However, many points remain to be clarified. In this mini-review we reported the latest observations on the effects of physical exercise on healthy skeletal and cardiac muscle focusing on muscle stem cells. The last ones represent the fundamental elements for muscle regeneration post injury, but also for healthy muscle homeostasis. Interestingly, in both muscle tissues the morphological consequence of physical activity is a physiological hypertrophy that depends on different phenomena both in differentiated cells and stem cells. The signaling pathways for physical exercise effects present common elements in skeletal and cardiac muscle, like activation of specific transcription factors, proliferative pathways, and cytokines. More recently, post translational (miRNAs) or epigenetic (DNA methylation) modifications have been demonstrated. However, several points remain unresolved thus requiring new research on the effect of exercise on muscle stem cells.
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Affiliation(s)
- Gabriele Ceccarelli
- Department of Public Health, Experimental Medicine and Forensic, University of Pavia, Pavia, Italy.,Center of Health Technologies (CHT), University of Pavia, Pavia, Italy
| | - Laura Benedetti
- Department of Public Health, Experimental Medicine and Forensic, University of Pavia, Pavia, Italy.,Center of Health Technologies (CHT), University of Pavia, Pavia, Italy
| | - Maria Luisa Arcari
- Department of Medicine and Surgery, S.Bi.Bi.T. Unit, University of Parma, Parma, Italy
| | - Cecilia Carubbi
- Department of Medicine and Surgery, S.Bi.Bi.T. Unit, University of Parma, Parma, Italy
| | - Daniela Galli
- Department of Medicine and Surgery, S.Bi.Bi.T. Unit and Sport and Exercise Medicine Center (SEM)., University of Parma c/o Ospedale Maggiore, Via Gramsci, 14, 43126, Tel: +39-0521-036306, , Parma, Italy.,Department of Medicine and Surgery, S.Bi.Bi.T. Unit, University of Parma, Parma, Italy
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3
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Bertholdt L, Gudiksen A, Schwartz CL, Knudsen JG, Pilegaard H. Lack of skeletal muscle IL-6 influences hepatic glucose metabolism in mice during prolonged exercise. Am J Physiol Regul Integr Comp Physiol 2017; 312:R626-R636. [PMID: 28122718 DOI: 10.1152/ajpregu.00373.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 01/23/2017] [Accepted: 01/23/2017] [Indexed: 01/06/2023]
Abstract
The liver is essential in maintaining and regulating glucose homeostasis during prolonged exercise. IL-6 has been shown to be secreted from skeletal muscle during exercise and has been suggested to signal to the liver. Therefore, the aim of this study was to investigate the role of skeletal muscle IL-6 on hepatic glucose regulation and substrate choice during prolonged exercise. Skeletal muscle-specific IL-6 knockout (IL-6 MKO) mice (age, 12-14 wk) and littermate lox/lox (Control) mice were either rested (Rest) or completed a single bout of exercise for 10, 60, or 120 min, and the liver was quickly obtained. Hepatic IL-6 mRNA was higher at 60 min of exercise, and hepatic signal transducer and activator of transcription 3 was higher at 120 min of exercise than at rest in both genotypes. Hepatic glycogen was higher in IL-6 MKO mice than control mice at rest, but decreased similarly during exercise in the two genotypes, and hepatic glucose content was lower in IL-6 MKO than control mice at 120 min of exercise. Hepatic phosphoenolpyruvate carboxykinase mRNA and protein increased in both genotypes at 120 min of exercise, whereas hepatic glucose 6 phosphatase protein remained unchanged. Furthermore, IL-6 MKO mice had higher hepatic pyruvate dehydrogenase (PDH)Ser232 and PDHSer300 phosphorylation than control mice at rest. In conclusion, hepatic gluconeogenic capacity in mice is increased during prolonged exercise independent of muscle IL-6. Furthermore, Skeletal muscle IL-6 influences hepatic substrate regulation at rest and hepatic glucose metabolism during prolonged exercise, seemingly independent of IL-6 signaling in the liver.
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Affiliation(s)
- Lærke Bertholdt
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Anders Gudiksen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Jakob G Knudsen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
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4
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Tao L, Bei Y, Zhang H, Xiao J, Li X. Exercise for the heart: signaling pathways. Oncotarget 2016; 6:20773-84. [PMID: 26318584 PMCID: PMC4673228 DOI: 10.18632/oncotarget.4770] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 07/10/2015] [Indexed: 12/30/2022] Open
Abstract
Physical exercise, a potent functional intervention in protecting against cardiovascular diseases, is a hot topic in recent years. Exercise has been shown to reduce cardiac risk factors, protect against myocardial damage, and increase cardiac function. This improves quality of life and decreases mortality and morbidity in a variety of cardiovascular diseases, including myocardial infarction, cardiac ischemia/reperfusion injury, diabetic cardiomyopathy, cardiac aging, and pulmonary hypertension. The cellular adaptation to exercise can be associated with both endogenous and exogenous factors: (1) exercise induces cardiac growth via hypertrophy and renewal of cardiomyocytes, and (2) exercise induces endothelial progenitor cells to proliferate, migrate and differentiate into mature endothelial cells, giving rise to endothelial regeneration and angiogenesis. The cellular adaptations associated with exercise are due to the activation of several signaling pathways, in particular, the growth factor neuregulin1 (NRG1)-ErbB4-C/EBPβ and insulin-like growth factor (IGF)-1-PI3k-Akt signaling pathways. Of interest, microRNAs (miRNAs, miRs) such as miR-222 also play a major role in the beneficial effects of exercise. Thus, exploring the mechanisms mediating exercise-induced benefits will be instrumental for devising new effective therapies against cardiovascular diseases.
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Affiliation(s)
- Lichan Tao
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Yihua Bei
- Regeneration and Ageing Lab and Experimental Center of Life Sciences, School of Life Science, Shanghai University, Shanghai 200444, China.,Shanghai Key Laboratory of Bio-Energy Crops, School of Life Science, Shanghai University, Shanghai 200444, China
| | - Haifeng Zhang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Junjie Xiao
- Regeneration and Ageing Lab and Experimental Center of Life Sciences, School of Life Science, Shanghai University, Shanghai 200444, China.,Shanghai Key Laboratory of Bio-Energy Crops, School of Life Science, Shanghai University, Shanghai 200444, China
| | - Xinli Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
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5
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Bishop-Bailey D. Mechanisms governing the health and performance benefits of exercise. Br J Pharmacol 2014; 170:1153-66. [PMID: 24033098 DOI: 10.1111/bph.12399] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 07/18/2013] [Accepted: 07/23/2013] [Indexed: 12/18/2022] Open
Abstract
Humans are considered among the greatest if not the greatest endurance land animals. Over the last 50 years, as the population has become more sedentary, rates of cardiovascular disease and its associated risk factors such as obesity, type 2 diabetes and hypertension have all increased. Aerobic fitness is considered protective for all-cause mortality, cardiovascular disease, a variety of cancers, joint disease and depression. Here, I will review the emerging mechanisms that underlie the response to exercise, focusing on the major target organ the skeletal muscle system. Understanding the mechanisms of action of exercise will allow us to develop new therapies that mimic the protective actions of exercise.
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Affiliation(s)
- D Bishop-Bailey
- Comparative Biomedical Sciences, The Royal Veterinary College, London, UK
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6
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Choudhury M, Qadri I, Rahman SM, Schroeder-Gloeckler J, Janssen RC, Friedman JE. C/EBPβ is AMP kinase sensitive and up-regulates PEPCK in response to ER stress in hepatoma cells. Mol Cell Endocrinol 2011; 331:102-8. [PMID: 20797423 PMCID: PMC2981635 DOI: 10.1016/j.mce.2010.08.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 08/12/2010] [Accepted: 08/17/2010] [Indexed: 01/11/2023]
Abstract
Diabetes and obesity are associated with activation of endoplasmic reticulum (ER) stress; however a direct link between ER stress and increased hepatic gluconeogenesis remains unclear. Here we show that ER stress triggers a significant increase in expression of CCAAT/enhancer-binding protein (C/EBPβ) and phosphorylated CREB together with reduced phospho-AMP-activated protein kinase (pAMPK) in hepatoma cells. ER stress contributed to transcriptional activation of the gluconeogenic phosphoenolpyruvate carboxykinase (PEPCK) promoter in Huh7 and HepG2 cells via cAMP binding motif (CRE site). Chromatin immunoprecipitation assays demonstrate that C/EBPβ is recruited to the PEPCK promoter during ER stress and is reversed by pre-treatment with a JNK inhibitor that relieves ER stress. C/EBPβ but not pCREB was suppressed by the AMPK-activator AICAR or constitutively active AMPK, while dominant negative AMPK increased C/EBPβ expression. These data suggest that ER stress triggers suppression of AMPK while increasing C/EBPβ and pCREB expression which activates PEPCK gene transcription. Understanding how ER stress suppresses AMPK activation and increases C/EBPβ expression could lead to a potentially novel pathway for treatment of diabetes.
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Affiliation(s)
- Mahua Choudhury
- Department of Pediatrics, University of Colorado Denver, Aurora, CO 80045, USA
| | - Ishtiaq Qadri
- Department of Pediatrics, University of Colorado Denver, Aurora, CO 80045, USA
| | | | | | - Rachel C. Janssen
- Department of Pediatrics, University of Colorado Denver, Aurora, CO 80045, USA
| | - Jacob E. Friedman
- Department of Pediatrics, University of Colorado Denver, Aurora, CO 80045, USA
- Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, CO 80045, USA
- Corresponding author: University of Colorado Denver, Department of Pediatrics, P.O. Box 6511, MS 8106, Aurora, CO 80045, USA. Tel.: +1 303 724 3983; fax: +1 303 724 3920.
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7
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Hoene M, Franken H, Fritsche L, Lehmann R, Pohl AK, Häring HU, Zell A, Schleicher ED, Weigert C. Activation of the mitogen-activated protein kinase (MAPK) signalling pathway in the liver of mice is related to plasma glucose levels after acute exercise. Diabetologia 2010; 53:1131-41. [PMID: 20195842 DOI: 10.1007/s00125-010-1666-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 12/17/2009] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS We aimed to identify, in the liver of mice, signal transduction pathways that show a pronounced regulation by acute exercise. We also aimed to elucidate the role of metabolic stress in this response. METHODS C57Bl6 mice performed a 60 min run on a treadmill under non-exhaustive conditions. Hepatic RNA and protein lysates were prepared immediately after running and used for whole-genome-expression analysis, quantitative real-time PCR and immunoblotting. A subset of mice recovered for 3 h after the treadmill run. A further group of mice performed the treadmill run after having received a vitamin C- and vitamin E-enriched diet over 4 weeks. RESULTS The highest number of genes differentially regulated by exercise in the liver was found in the mitogen-activated protein kinase (MAPK) signalling pathway, with a pronounced and transient upregulation of the transcription factors encoded by c-Fos (also known as Fos), c-Jun (also known as Jun), FosB (also known as Fosb) and JunB (also known as Junb) and phosphorylation of hepatic MAPK. Acute exercise also activated the p53 signalling pathway. A major role for oxidative stress is unlikely since the antioxidant-enriched diet did not prevent the activation of the MAPK pathway. In contrast, lower plasma glucose levels after running were related to enhanced levels of MAPK signalling proteins, similar to the upregulation of Igfbp1 and Pgc-1alpha (also known as Ppargc1a). In the working muscle the activation of the MAPK pathway was weak and not related to plasma glucose concentrations. CONCLUSIONS/INTERPRETATION Metabolic stress evidenced as low plasma glucose levels appears to be an important determinant for the activation of the MAPK signalling pathway and the transcriptional response of the liver to acute exercise.
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Affiliation(s)
- M Hoene
- Division of Endocrinology, Diabetology, Angiology, Nephrology, Pathobiochemistry and Clinical Chemistry, Department of Internal Medicine, University Hospital of Tuebingen, Otfried-Mueller-Strasse 10, D-72076 Tuebingen, Germany
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8
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Banzet S, Koulmann N, Simler N, Sanchez H, Chapot R, Serrurier B, Peinnequin A, Bigard X. Control of gluconeogenic genes during intense/prolonged exercise: hormone-independent effect of muscle-derived IL-6 on hepatic tissue and PEPCK mRNA. J Appl Physiol (1985) 2009; 107:1830-9. [PMID: 19850730 DOI: 10.1152/japplphysiol.00739.2009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Prolonged intense exercise is challenging for the liver to maintain plasma glucose levels. Hormonal changes cannot fully account for exercise-induced hepatic glucose production (HGP). Contracting skeletal muscles release interleukin-6 (IL-6), a cytokine able to increase endogenous glucose production during exercise. However, whether this is attributable to a direct effect of IL-6 on liver remains unknown. Here, we studied hepatic glycogen, gluconeogenic genes, and IL-6 signaling in response to one bout of exhaustive running exercise in rats. To determine whether IL-6 can modulate gluconeogenic gene mRNA independently of exercise, we injected resting rats with recombinant IL-6. Exhaustive exercise resulted in a profound decrease in liver glycogen and an increase in gluconeogenic gene mRNA levels, phosphoenolpyruvate-carboxykinase (PEPCK), glucose-6-phosphatase (G6P), and peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha), suggesting a key role for gluconeogenesis in hepatic glucose production. This was associated to an active IL-6 signaling in liver tissue, as shown by signal transducer and activator of transcription and CAAT/enhancer binding protein-beta phosphorylation and IL-6-responsive gene mRNA levels at the end of exercise. Recombinant IL-6 injection resulted in an increase in IL-6-responsive gene mRNA levels in the liver. We found a dose-dependent increase in PEPCK gene mRNA strongly correlated with IL-6-induced gene mRNA levels. No changes in G6P and PGC-1alpha mRNA levels were found. Taken together, our results suggest that, during very demanding exercise, muscle-derived IL-6 could help increase HGP by directly upregulating PEPCK mRNA abundance.
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Affiliation(s)
- Sébastien Banzet
- Department of Human Factors, Military Health Service Research Center, La Tronche, France.
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9
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Hoene M, Lehmann R, Hennige AM, Pohl AK, Häring HU, Schleicher ED, Weigert C. Acute regulation of metabolic genes and insulin receptor substrates in the liver of mice by one single bout of treadmill exercise. J Physiol 2008; 587:241-52. [PMID: 19001047 DOI: 10.1113/jphysiol.2008.160275] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Acute exercise performance represents a major metabolic challenge for the skeletal muscle, but also for the liver as the most important source of energy. However the molecular adaptation of the liver to one single bout of exercise is largely unknown. C57BL/6 mice performed a 60 min treadmill run at high aerobic intensity. Liver, soleus and white gastrocnemius muscle were removed immediately after exercise. The single bout of exercise resulted in a very rapid and pronounced induction of hepatic metabolic enzymes and regulators of metabolism or transcription: glucose-6-phosphatase (G6Pase; 3-fold), pyruvate dehydrogenase kinase-4 (PDK4; 4.8-fold), angiopoietin-like 4 (2.1-fold), insulin receptor substrate (IRS)-2 (5.1-fold), peroxisome proliferator activated receptor-gamma coactivator 1alpha (PGC-1alpha; 3-fold). In soleus and white gastrocnemius muscle the up-regulation of IRS-2 and PDK4 was less pronounced compared with the liver and no significant induction of PGC-1alpha could be detected at this early time point. Activation of AMPK was found in both liver and white gastrocnemius muscle as phosphorylation of Thr-172. The induction of endogenous insulin secretion by a glucose load directly after the exercise bout resulted in a significantly higher PKB/Akt phosphorylation in the liver of exercised mice. The markedly enhanced IRS-2 protein amount, and presumably reduced serine/threonine phosphorylation of the IRS proteins induced by the acute exercise could be responsible for this enhanced action of insulin. In conclusion, acute exercise induced a rapid and pronounced transcriptional adaptation in the liver, and regulated hepatic IRS proteins leading to improved cellular insulin signal transduction.
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Affiliation(s)
- Miriam Hoene
- Division of Pathobiochemistry and Clinical Chemistry, University of Tuebingen, Otfried-Mueller-Strasse 10, D-72076 Tuebingen, Germany
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10
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Schroeder-Gloeckler JM, Rahman SM, Janssen RC, Qiao L, Shao J, Roper M, Fischer SJ, Lowe E, Orlicky DJ, McManaman JL, Palmer C, Gitomer WL, Huang W, O’Doherty RM, Becker TC, Klemm DJ, Jensen DR, Pulawa LK, Eckel RH, Friedman JE. CCAAT/enhancer-binding protein beta deletion reduces adiposity, hepatic steatosis, and diabetes in Lepr(db/db) mice. J Biol Chem 2007; 282:15717-29. [PMID: 17387171 PMCID: PMC4109269 DOI: 10.1074/jbc.m701329200] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
CCAAT/enhancer-binding protein beta (C/EBPbeta) plays a key role in initiation of adipogenesis in adipose tissue and gluconeogenesis in liver; however, the role of C/EBPbeta in hepatic lipogenesis remains undefined. Here we show that C/EBPbeta inactivation in Lepr(db/db) mice attenuates obesity, fatty liver, and diabetes. In addition to impaired adipogenesis, livers from C/EBPbeta(-/-) x Lepr(db/db) mice had dramatically decreased triglyceride content and reduced lipogenic enzyme activity. C/EBPbeta deletion in Lepr(db/db) mice down-regulated peroxisome proliferator-activated receptor gamma2 (PPARgamma2) and stearoyl-CoA desaturase-1 and up-regulated PPARalpha independent of SREBP1c. Conversely, C/EBPbeta overexpression in wild-type mice increased PPARgamma2 and stearoyl-CoA desaturase-1 mRNA and hepatic triglyceride content. In FAO cells, overexpression of the liver inhibiting form of C/EBPbeta or C/EBPbeta RNA interference attenuated palmitate-induced triglyceride accumulation and reduced PPARgamma2 and triglyceride levels in the liver in vivo. Leptin and the anti-diabetic drug metformin acutely down-regulated C/EBPbeta expression in hepatocytes, whereas fatty acids up-regulate C/EBPbeta expression. These data provide novel evidence linking C/EBPbeta expression to lipogenesis and energy balance with important implications for the treatment of obesity and fatty liver disease.
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Affiliation(s)
- Jill M. Schroeder-Gloeckler
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Shaikh Mizanoor Rahman
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Rachel C. Janssen
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Liping Qiao
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Jianhua Shao
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Michael Roper
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Stephanie J. Fischer
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Erin Lowe
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - David J. Orlicky
- Department of Pathology, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - James L. McManaman
- Department of Obstetrics and Gynecology, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
- Department of Physiology and Biophysics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Carol Palmer
- Department of Obstetrics and Gynecology, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | | | - Wan Huang
- Department of Medicine, Division of Endocrinology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Robert M. O’Doherty
- Department of Medicine, Division of Endocrinology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Thomas C. Becker
- Division of Endocrinology, Nutrition, and Metabolism, Duke University Medical Center, Durham, North Carolina 27704
| | - Dwight J. Klemm
- Pulmonary Sections, Research Service, Veterans Affairs Medical Center, Denver, Colorado 80220
- Department of Biochemistry and Molecular Genetics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Dalan R. Jensen
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Leslie K. Pulawa
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Robert H. Eckel
- Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
| | - Jacob E. Friedman
- Department of Pediatrics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
- Department of Biochemistry and Molecular Genetics, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045
- To whom correspondence should be addressed: Depts. of Pediatrics and Biochemistry and Molecular Genetics, UCDHSC-Mail Stop F-8106, P.O. Box 6511, Aurora, CO 80045. Tel.: 303-724-3983; Fax: 303-724-3920;
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11
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Harrison BC, Bell ML, Allen DL, Byrnes WC, Leinwand LA. Skeletal muscle adaptations in response to voluntary wheel running in myosin heavy chain null mice. J Appl Physiol (1985) 2002; 92:313-22. [PMID: 11744674 DOI: 10.1152/japplphysiol.00832.2001] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
10.1152/ japplphysiol.00832.2001.-To examine the effects of gene inactivation on the plasticity of skeletal muscle, mice null for a specific myosin heavy chain (MHC) isoform were subjected to a voluntary wheel-running paradigm. Despite reduced running performance compared with nontransgenic C57BL/6 mice (NTG), both MHC IIb and MHC IId/x null animals exhibited increased muscle fiber size and muscle oxidative capacity with wheel running. In the MHC IIb null animals, there was no significant change in the percentage of muscle fibers expressing a particular MHC isoform with voluntary wheel running at any time point. In MHC IId/x null mice, wheel running produced a significant increase in the percentage of fibers expressing MHC IIa and MHC I and a significant decrease in the percentage of fibers expressing MHC IIb. Muscle pathology was not affected by wheel running for either MHC null strain. In summary, despite their phenotypes, MHC null mice do engage in voluntary wheel running. Although this wheel-running activity is lessened compared with NTG, there is evidence of distinct patterns of muscle adaptation in both null strains.
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Affiliation(s)
- B C Harrison
- Department of Kinesiology and Applied Physiology, Cellular and Developmental Biology, University of Colorado at Boulder, 80309, USA
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