title: Muscle-derived expression of the chemokine CXCL1 attenuates diet-induced obesity and improves fatty acid oxidation in the muscle.
abstract: Serum levels and muscle expression of the chemokine CXCL1 increase markedly in response to exercise in mice. Because several studies have established muscle-derived factors as important contributors of metabolic effects of exercise, this study aimed at investigating the effect of increased expression of muscle-derived CXCL1 on systemic and intramuscular metabolic parameters, with focus on fatty acid oxidation and oxidative metabolism in skeletal muscle. By overexpression of CXCL1 in the tibialis cranialis muscle in mice, significant elevations in muscle and serum CXCL1 within a physiological range were obtained. At 3 mo of high-fat feeding, visceral and subcutaneous fat mass were 32.4 (P < 0.01) and 22.4% (P < 0.05) lower, respectively, in CXCL1-overexpressing mice compared with control mice. Also, chow-fed CXCL-transfected mice had 35.4% (P < 0.05) lower visceral fat mass and 33.4% (P < 0.05) lower subcutaneous fat mass compared with chow-fed control mice. These reductions in accumulation of adipose tissue were accompanied by improved glucose tolerance and insulin sensitivity. Furthermore, in CXCL1-transfected muscles, muscular ex vivo fatty acid oxidation was significantly enhanced compared with control muscles (chow fed: 2.2-fold, P < 0.05; high-fat fed: 2-fold, P < 0.05) and also showed increased expression levels of major fatty acid oxidation genes (CD36, CPT I, and HADH). Finally, CXCL1 expression was associated with increased muscle mRNA expression of VEGF and CD31, suggesting a role for CXCL1 in muscle angiogenesis. In conclusion, our data show that overexpression of CXCL1 within a physiological range attenuates diet-induced obesity, likely mediated through a CXCL1-induced improvement of fatty acid oxidation and oxidative capacity in skeletal muscle tissue.
authors.affiliation: Centre of Inflammation and Metabolism, Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Line
authors.initials: L
authors.lastname: Pedersen
authors.forename: Caroline Holkmann
authors.initials: CH
authors.lastname: Olsen
authors.forename: Bente Klarlund
authors.initials: BK
authors.lastname: Pedersen
authors.forename: Pernille
authors.initials: P
authors.lastname: Hojman
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001823:Body Composition / Q000235:genetics / Q000502:physiology; D001835:Body Weight / Q000235:genetics / Q000502:physiology; D054360:Chemokine CXCL1 / Q000235:genetics / Q000502:physiology*; D016207:Cytokines / Q000097:blood; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D004032:Diet; D004435:Eating / Q000235:genetics / Q000502:physiology; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D005951:Glucose Tolerance Test; D051379:Mice; D008810:Mice, Inbred C57BL; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D018919:Neovascularization, Physiologic / Q000235:genetics / Q000502:physiology; D009765:Obesity / Q000378:metabolism*; D010084:Oxidation-Reduction; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014162:Transfection; D015854:Up-Regulation / Q000502:physiology; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis / Q000235:genetics
chemical_list: D054360:Chemokine CXCL1; D016207:Cytokines; D005230:Fatty Acids, Nonesterified; D009124:Muscle Proteins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A; D004247:DNA