γ干扰素诱导小鼠肾小球系膜细胞表达IP-10及其机制研究

Effect of IFN-γ on the expression of IP-10 in mice mesangial cells and its mechanisminduced

目的探讨γ干扰素对小鼠肾小球系膜细胞(MMC)表达γ干扰素诱导蛋白10(IP-10)的影响及其机制。方法将MMC随机分为空白组、γ干扰素刺激组、α-氰基-(3,4-羟基)-N-苄苯乙烯胺(AG490)干预组,运用实时荧光定量PCR检测IP-10 mRNA相对表达量;酶联免疫吸附测定法检测细胞培养上清液中IP-10蛋白分泌量;蛋白质印迹法检测JAK/STAT1信号通路相关蛋白JAK1、JAK2、STAT1及其磷酸化蛋白p-JAK1、p-JAK2、p-STAT1表达情况。结果γ干扰素刺激MMC后IP-10 mRNA及蛋白分泌量明显增多(P<0.01),并呈浓度、时间依赖性;AG490干预后,与刺激组相比,IP-10 mRNA相对表达量下降了81.16%(P<0.01),IP-10蛋白分泌量下降了91.81%(P<0.01);γ干扰素刺激后p-JAK1、p-JAK2、p-STAT1蛋白表达明显增加(P<0.01),经AG490干预后p-JAK1、p-JAK2、p-STAT1蛋白表达减少(P<0.01)。结论γ干扰素通过激活JAK/STAT1信号通路诱导MMC表达IP-10;抑制JAK/STAT1信号通路对减少MMC表达IP-10具有重要意义。

Objective To investigate the effect of IFN-γ on the expression of IP-10 in mouse mesangial cells （MMC） and its possible mechanism. Methods MMC were randomly divided into blank group, IFN-γ stimula- tion group, AG490 intervention group. Real-time PCR was used to detect the expression of IP-10 mRNA.ELISA was employed to detect the secretion of IP-10 in cell culture supernatant. Western blot was utilized to detect the expression of JAK/STAT1 signaling pathway related JAkl, JAK2, STAT1 and the phosphated protein p-JAK1, p-JAK2, p-STAT1. Results The IP-10 mRNA and secretion of protein were significantly in- creased （P 〈 0.01） in a dose and time-dependent manner after stimulated by IFN-γ. AG490 intervention treat- ment, the expression level of IP-10 mRNA was decreased 81.16% （P 〈 0.01） compared to IFN-γ stimulation group, and the IP-10 protein secretion was decreased 91.81% （P 〈 0.01）. Western blot results showed IFN-γ significantly enhancedthe expression of p-JAK1, p-JAK2, p-STAT1 protein when compared with the blank group （P 〈 0.01）, AG490 intervention rediced the expression ofp-JAK1, p-JAK2, p-STAT1 protein （P 〈 0.01）. Conclusion IFN-γ induces IP-10 expression by activating JAK/STAT1 signaling pathway, the inhibition of JAK/STAT1 signaling pathway has important significance for reducing expression IP-10 inMMC.