TabMenu

Poverty and InequalitySexual and Reproductive HealthFamily, Maternal & Child HealthMethodology

Muscle-selective knockout of AMPKalpha2 does not exacerbate diet-induced obesity probably related to altered myokines expression

TitleMuscle-selective knockout of AMPKalpha2 does not exacerbate diet-induced obesity probably related to altered myokines expression
Publication TypeJournal Article
Year of Publication2015
AuthorsChen, T, Li, Z, Zhang, Y, Feng, F, Wang, X, Wang, X, Shen, QW
JournalBiochem Biophys Res Commun
Volume458
Pagination449-55
Date PublishedMar 13
ISBN Number1090-2104 (Electronic)0006-291X (Linking)
Accession Number25637528
KeywordsAmpkα2, Insulin Resistance, Lipid metabolism, Myokine, Obesity
Abstract

Dysregulation of lipid metabolism has been believed to be central in the development of skeletal muscle insulin resistance. Since first being described in 1989, the role of AMPK in energy metabolism, especially its role in lipid metabolism in skeletal muscle has been well studied. However, some recent literature report that fatty acid oxidation in skeletal muscle is not directly associated with AMPK activation and ACC phosphorylation. To further understand the role of AMPK in lipid metabolism and the development of induced obesity and insulin resistance, muscle specific AMPKalpha2 knockout mice (mAMPKalpha2-KO) was employed in this study. The results showed that AMPKalpha2 ablation in muscle did not exacerbate high fat diet induce obesity in mice. On the contrary, it improved animal glucose tolerance and insulin sensitivity, with reduced triglyceride content in skeletal muscle and fat mass in various adipose tissues, when mice were fed high fat diet for 14 weeks. Gene expression analysis revealed that AMPKalpha2 knockout up-regulated the expression of genes related to lipid catabolism and down-regulated that of genes related to triglyceride synthesis. More importantly, ablation of AMPKalpha2 altered the expression of several myokines related to adipogenesis and muscle regeneration. Our data suggest that defect in AMPKalpha2 signaling does not necessarily lead to the development of muscle insulin resistance and obesity. AMPKalpha2 may regulate whole body lipid metabolism by regulating myokine secretion.