Expression of Adenosine Monophosphate-Activated Protein Kinase Subunit Related to the Rate of Intramuscular Lipogenesis in Fast and Slow-Growing Chicken Strains

Abstract

The objective of this study was to compare the expression of adenosine monophosphate-activated protein kinase ( AMPK) and its relation to rates of lipogenesis in the muscle of fast (Arbor Acres, AA chickens)-and slow (Bei-Jing-You, BJY chickens)-growing chicken strains. Twelve birds for each strain were selected and slaughtered at 8 weeks of age for AA chickens and week 8, week 16 for BJY chickens. The amount of intramuscular fat (IMF) content, expression of AMPK subunits and key regulators of lipogenesis in the thigh and breast muscle tissue were determined. Results showed that the content of IMF and expression of peroxisome proliferator activated receptors γ, FA translocase CD36 and fatty acid synthase in the thigh and breast muscle of week 16 BJY were significantly higher than those for week 8 AA and week 8 BJY chickens ( P < 0.05). Compared with AA chickens at 8 weeks, at 16 weeks, the BJY showed a significantly lower expression of AMPK subunits (except subunits α1 and γ3 in thigh and β1 and γ2 in breast) in the muscle ( P < 0.05). To examine the role of AMPK on adipogenesis, the muscle-derived stromal-vascular cells were cultured in adipogenic medium and treated with AICAR and Compound C. The administration of compound C significantly induced expression of CCAAT/enhancer-binding protein factors β, sterol regulatory element-binding protein 1 and peroxisome proliferator activated receptors γ ( P < 0.05), and AICAR-induced AMPK activation inhibited adipogenic gene expression. In conclusion, there was a significantly higher IMF content and lipogenic gene expression in week 16 BJY than week 8 AA. AMPK expression negatively related to intramuscular lipid in chickens.