Short communication: effects of dietary corticosterone on the central AMPK signaling pathway in broiler chickens.

Glucocorticoids (GCs) induce the activation of the central adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling pathway in birds. In this study, we aimed to investigate the effects of corticosterone (CORT) supplemented in diet on the central AMPK signaling pathway in broilers. Average daily gain (ADG) was reduced by CORT treatment, and average daily feed intake (ADFI) remained unchanged. Plasma glucose (GLU), triglyceride (TG), total cholesterol (TCHO) and CORT contents were increased by CORT administration. In addition, CORT treatment decreased the relative weights of heart, spleen and bursa, and increased the relative weights of liver and abdominal fat. The glycogen contents in the liver and breast muscle were higher in the chicks treated with CORT. CORT treatment upregulated the gene expression of mammalian target of rapamycin (mTOR), glucocorticoid receptor (GR), AMP-activated protein kinase α2 (AMPKα2), neuropeptide Y (NPY), liver kinase B1 (LKB1), AMP-activated protein kinase α1 (AMPKα1), and fatty acid synthase (FAS) in the hypothalamus. Moreover, CORT treatment increased the protein levels of acetyl-coenzyme A carboxylase (ACC) phosphorylation, and total AMPK and phosphorylated AMPK in the hypothalamus. Hence, CORT administration in the diet activated the LKB1-AMPK-NPY/ACC signaling pathway in the hypothalamus of broiler.