The Lipidmetabolism In Muscle-Selective Knockout AMPKα2 Mice Under High Fat Feeding

Dysregulation of lipid metabolism has been believed tobe central in the development of skeletal muscle insulin resistance. Since 1989, the role of AMPK in energy metabolism, especially its role in lipid metabolism in skeletal muscle has been well studied. However, some recent literatures 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 AMPKα2 knockout mice(mAMPKα2-KO) was employed in this study. We tested thePhysiologicalmeasures of mAMPKα2-KO mice, the mRNA expressionsofgenes related to lipid catabolism and the the expression of several myokines related to adipogenesis and muscle regeneration. The main results were follows:1,we generated the muscle specific AMPKα2 knockout mice.we used the PCR and Western Bloting techniques to confirm the theessentialcorrectness of the mAMPKα2-KO mice.2,Physiological effects of muscle-specific knockout of AMPKα2. Our results showed that AMPKα2 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.3, AMPKα2 ablation in muscle alters the expression of genes related to lipid metabolism.Gene expression analysis revealed that AMPKα2 knockout up-regulated the expression of genes related to lipid catabolism and down-regulated that of genes related to triglyceride synthesis.4,AMPKα2 knockout changes the expression of myokines inskeletal muscle. ablation of AMPKα2 altered the expression of several myokines related to adipogenesis and muscle regeneration.Conclusion:our data suggest that defect in AMPKα2 signaling does not necessarily lead to the development of muscle insulin resistance and obesity. AMPKα2 may regulate whole body lipid metabolism by regulating myokine secretion.