食欲素A调控INS-1胰岛素瘤细胞的细胞增殖的分子机制

摘要

Objective To investigate the interference effects of orexin A on cell proliferation of the insulin⁃secreting beta⁃cell line(INS⁃1 cells) through the orexin receptor 1(OX1R)and the AKT/PKB signaling pathway. Methods INS⁃1 cells were exposed to different concentrations of orexin A in vitro,and treated with OX1R antagonist(SB334867),PI3K antagonist(wortmannin),or AKT antagonist(PF⁃04691502). The INS⁃1 cell proliferation and apoptosis,insulin secretion,OX1R protein activity and AKT phosphorylation level were determined. Results Orexin A(10-10 to 10-6 mol/L)stimulated the proliferation and activation of INS⁃1 cells,prevented apoptpsis,and increased insulin secretion. Additionally,AKT phosphorylation was stimulated by orexin A(10-10 to 10-6 mol/L). The OX1R antagonist SB334867(10-6 mol/L),the PI3K antagonist wortmannin (10-8 mol/L)and the AKT antagonist PF⁃04691502(10-6 mol/L)weakened the effects of orexin A. Conclusion Orexin A activated the AKT sig⁃naling pathway through the mediation of orexin A⁃OX1R,and promoted cell proliferation in INS⁃1 cells.%目的：探讨增食欲素A（Orexin A）通过增食欲素受体1（OX1R）和AKT/PKB信号传导途径对胰岛细胞增殖的干预效应。方法体外培养的大鼠INS⁃1胰岛素瘤细胞暴露于不同浓度的Orexin A，OX1R拮抗剂（SB334867）、PI3K拮抗剂（渥曼青霉素）和AKT拮抗剂（PF⁃04691502）干预Orexin A的作用，测定INS⁃1的细胞增殖、凋亡、胰岛素分泌、OX1R蛋白活性及AKT蛋白磷酸化水平。结果 Orexin A（10-10~10-6 mol/L）可刺激INS⁃1细胞的增殖和活化，防止细胞凋亡，并增加胰岛素的分泌；Orexin A （10-10~10-6 mol/L）增强了INS⁃1细胞内AKT的磷酸化，SB334867（10-6 mol/L）、渥曼青霉素（10-8 mol/L）和PF⁃04691502（10-6 mol/L）可以减弱Orexin A的作用。结论 INS⁃1细胞内Orexin A通过Orexin A⁃OX1R的介导而活化AKT信号通路，促进细胞增殖。