Orexin-A （OxA） is a key neuropeptide involved in the central control of appetite and the maintenance of energy homeostasis, as well as in the regulation of glycemia. In the present study, OxA receptors, OXtR and OX2...Orexin-A （OxA） is a key neuropeptide involved in the central control of appetite and the maintenance of energy homeostasis, as well as in the regulation of glycemia. In the present study, OxA receptors, OXtR and OX2R were identified to be highly expressed in porcine hepatocytes. 100 nM OxA could rapidly stimulate the glucose output of porcine hepatocytes in 10min. Primary hepatocytes treated by 1 nM-500 nM OxA for 24 h significantly increase the released glucose and the concentration of albumin, total bile acids and triglyceride in the supernatant. The mRNA expression level of such gluconeogenesis and fat mobilization related genes as acetyl-coA carboxylase, glycogen phosphorylase, fatty acid translocase and phosphoenolpyrurate carboxykinase were also up-regulated accordingly. The results first demonstrated that OxA had direct effect on the hepatic glucose and lipid metabolism, which was an aspect for OxA to exert its maintenance function of energy homeostasis.展开更多
基金Acknowledgements： This work was supported by the Joint Funds of the National Natural Science Foundation of China （No. u0731004）, National Natural Science Foundation of China （No. 30871845） and Natural Science Foundation of Guangdong Province of China （No. 07118116）.
文摘Orexin-A （OxA） is a key neuropeptide involved in the central control of appetite and the maintenance of energy homeostasis, as well as in the regulation of glycemia. In the present study, OxA receptors, OXtR and OX2R were identified to be highly expressed in porcine hepatocytes. 100 nM OxA could rapidly stimulate the glucose output of porcine hepatocytes in 10min. Primary hepatocytes treated by 1 nM-500 nM OxA for 24 h significantly increase the released glucose and the concentration of albumin, total bile acids and triglyceride in the supernatant. The mRNA expression level of such gluconeogenesis and fat mobilization related genes as acetyl-coA carboxylase, glycogen phosphorylase, fatty acid translocase and phosphoenolpyrurate carboxykinase were also up-regulated accordingly. The results first demonstrated that OxA had direct effect on the hepatic glucose and lipid metabolism, which was an aspect for OxA to exert its maintenance function of energy homeostasis.
