The Role And Mechanisms Of AMPK In Sheep Muscle Derived Preadipocytes Differentiation

Intramuscular fat content(IMF)directly affects the tenderness,succulence and flavor of meat.The intramuscular preadipocytes provide good tools for studying the mechanisms of intramuscular adipogenesis.The IMF’s content is influenced by genetics,nutrition,environment and other factors.AMPK is one of the most important enzymes for regulating energy metabolism in cells,and is involved in the metabolism of sugar,fat and protein.The objective of this study was to investigate the effect and mechanism of AMP-activated protein kinase(AMPK)on sheep muscle derived preadipocytes differentiation.In this experiment,The LD muscle was sampled from 3 d 1amb,and the perimysium was isolated and digested for preadipocytes isolation.The activity of AMPK and Wnt/β-catenin signaling pathway were altered,and qRT-PCR and Western blotting were used to evaluate the key genes expression pattern.Oil-Red-O staining was used to determine the lipid droplet in mature adipocytesThe experimental results show that:AMPK activation decreased Oil-Red-O staining,and down-regulate adipogenic genes expression,including PPARy,C/EBPα and aP2(P<0.01),while inhibition of AMPK activity showed opposite effects.Wnt/β-catenin signaling pathway activation blocked preadipocytes adipogenesis,while inhibition activity promoted adipogenesis.The β-catenin transcription was not affected by alteration of AMPK activity.Interestingly,AMPK activity was positively correlated with β-catenin protein content.Furthermore,AMPK activation increased GSK3β phosphorylation(P<0.01)In conclusion,AMPK activity influenced sheep muscle derived preadipocytes differentiation,which might through interaction with GSK3β and Wnt/β-catenin signaling pathway.