γ干扰素对高磷诱导大鼠血管平滑肌细胞钙化的影响研究

Effect of IFNγ on high phosphorus-induced calcification in rat vascular smooth muscle cells

目的探讨γ干扰素(IFNγ)对大鼠血管平滑肌细胞(VSMCs)钙化的影响,为临床治疗血管钙化提供新的线索。方法大鼠胸主动脉VSMCs原代培养,采用免疫细胞化学方法鉴定。将VSMCs随机分为阴性对照组、高磷组、IFNγ干预组(在高磷培养基的基础上加入100 U/L重组大鼠IFNγ),刺激3 d后RT-PCR对各组细胞内核心结合因子α1(Cbfα1)、骨形态发生蛋白2(BMP2)、Smad 1以及Smad 7的mRNA进行检测,刺激14 d后,对各组细胞进行钙化染色,钙含量及碱性磷酸酶(ALP)活性测定。结果与阴性对照组比较,高磷组及IFNγ干预组VSMCs均有钙盐沉积,ALP活性及Cbfα1的mRNA及蛋白表达均增高,BMP 2、Smad 1 mRNA表达也增高(均为P<0.05),与高磷组比较,IFNγ干预组VSMCs的钙盐沉积、ALP活性及Cbfα1 mRNA和蛋白表达均显著降低(均为P<0.05),BMP 2、Smad 1 mRNA表达也降低,而正常组和IFNγ干预组的VSMCs中Smad 7 mRNA表达均高于高磷组(均为P<0.05)。结论 IFNγ对高磷诱导的VSMCs钙化有抑制作用,其可能机制之一是通过抑制了VSMCs Cbfα1的表达,进而抑制了VSMCs的转分化来实现的。

Objective To explore the effect of IFNγ on rat vascular smooth muscle cell （ VSMCs） calcification. Methods VSMCs were obtained from rat aortic, and identified by immunocytochemistry, then randomly divided into control group, high phosphorus group and IFNγ intervention group. Calcification staining, calcium content and alkaline phosphatase activity were measured and the expressions of BMP2, Smad 1 and Cbfa 1 mRNA were detected by RT-PCR and the expression of Cbfa1 protein was detected by western blot, after stimulating 3 days. Results Compared with the control group, the high phosphorus groups cell calcification, alkaline phosphatase activity and the expressions of Cbfa1, BMP2, Smad1 mRNA were increased significantly （ all p 〈 0. 05 ） . Compared with the high phosphorus group, the calcium deposition, ALP activity and the expressions of BMP2,Smad 1 and Runx 2 mRNA in IFNy intervention group were decreased significantly （all p〈0. 05）. Conclusions IFNγ can reduce the calcification in rat vascular smooth muscle cells, may be due to inhibiting the transdifferentiation of vascular smooth muscle cells.