胃促生长素对人主动脉平滑肌细胞增殖及线粒体融合蛋白2表达的影响

目的 通过体外培养人主动脉平滑肌细胞(HASMCs),研究胃促生长素(ghrelin)对血管平滑肌细胞(VSMC)增殖及线粒体融合蛋白2(Mfn-2)表达的影响.方法 体外培养HASMCs,第4～6代细胞用于试验.给予不同浓度(10-9、10-8、10-7、10-6、10-5 mol/L)的ghrelin 或10-6 mol/L ghrelin不同时间(0、6、12、18、24 h)处理,用四甲基偶氮唑蓝比色(MMT)法观察其对HASMC增殖的影响.RT-PCR,Western blot方法检测不同处理方法对Mfn-2表达的影响.结果 10-7～10-5 mol/L的ghrelin可明显抑制HASMC增殖,浓度为10-6 mol/L抑制作用最为明显(P<0.01).ghrelin在6～24 h内均能明显抑制HASMC增殖,在24 h达最高峰(P<0.01).10-6 mol/L ghrelin能明显上调Mfn-2 mRNA和蛋白的表达(P<0.01).10-6 mol/L ghrelin在18 h上调Mfn-2 mRNA和蛋白表达的作用最为明显(P<0.01).结论 ghrelin可能通过上调Mfn-2的表达来抑制HASMC增殖.

Effect of ghrelin on proliferation and mitofusin-2 expression of human aortic smooth muscle cells

Objective To investigate the effects of ghrelin on proliferation of vascular smooth muscle cells(VSMC)and the expression of mitochondrial fusion 2(Mfn-2)in cultured human aortic smooth muscle cells(HASMCs).Methods HASMCs were cultured in vitro,treated with different concentrations(10-9,10-8,10-7,10-6,10-5 mol/L)ghrelin or 10-6 mol/L ghrelin for different time(0,6,12,18,24 h).Subconfluent HASMCs at passage 4-6 were used in experiments.MTT essay was used to investigate the effect on proliferation of HASMCs.RT-PCR and Western blot were used to analyse the expression of Mfn-2.Results 10-7-10-5 mol/L ghrelin inhibited the proliferation of HASMCs,and the inhibitory effect of concentration of 10-6 mol/L was the most obvious(P<0.01).Ghrelin inhibited the proliferation of HASMCs in 6-24 h,and it reached the peak at 24 h(P<0.01).10-6 mol/L ghrelin significantly increased the expression of Mfn-2 mRNA and protein(P<0.01).The up-regulation of 10-6 mol/L ghrelin on Mfn-2 mRNA and protein expression reached the peak at 18 h(P<0.01).Conclusion Ghrelin might inhibit the proliferation of HASMC by up-regulating the expression of Mfn-2.