Ghrelin activates translation initiate factor in human T cells through mTOR pathway / 中国免疫学杂志

ABSTRACT

Objective:Ghrelin is a brain-gut peptide with GH-releasing,apetide-inducing and anti-inflammation activities and with widespread tissue distribution.Ghrelin is the endogenous ligand of GH secretagogue receptor (GHSR),and both ghrelin and the GHSR are expressed in T cells.We therefore examined the effect of Ghrelin on human T cell and its signal transduction.Methods:Ghrelin-activating mTOR pathway in human primary T cell was studied using immunoblotting and inhibitors of the PI3K(LY294002,3-Methyladenine) or mTOR(rapamycin) and antagonist of GHSR1a(Des-Lys-3-GHRP6).Results:The results showed that GHSR1a was expressed on T cells.Ghrelin caused a significant increase in the phosphorylated mTOR,P70S6K,S6K,4E-BP-1,eIF4G,eIF4E by immunoblotting.While the phosphorylated mTOR,P70S6K were abolished by the mTOR inhibitor rapamycin and PI3K inhibitor LY294002,3-methyladenine and also antagonist of GHSR1a,Des-Lys-3-GHRP6.Conclusion:The data document that Ghrelin activates translation of T cells through mTOR pathway.