摘要
在足细胞凋亡的众多原因中,氧化应激是足细胞凋亡发生的基质,是肾脏病进展的最重要特征。足细胞凋亡时,氧化应激的确切机制及信号通路尚不完全明确。目的探讨平滑肌22α(smooth muscle 22 alpha,SM22α)通过phospho-p47^(phox)(p47^(phox))调控血管紧张素Ⅱ(AngiotensinⅡ,Ang Ⅱ)诱导的足细胞的氧化应激。方法①通过实时定量PCR(quantitative real time-polymerase chain reaction,q RT-PCR)技术检测足细胞在正常和AngⅡ刺激下,SM22α、p47^(phox)等蛋白的表达情况。②应用Western Blot技术观察足细胞在正常和AngⅡ刺激下SM22α、p47^(phox)表达变化。③敲减SM22α,检测p47^(phox)等的表达情况。④SM22α的磷酸化p47^(phox)的表达情况。结果①AngⅡ诱导下,足细胞的SM22α的mRNA表达显著下调(t12h=2.215,P12h=0.041),p47^(phox)的mRNA表达显著升高(t12h=3.955,P12h=0.025)。②AngⅡ刺激下,SM22α表达下调(t^(12h)=2.215,P^(12h)=0.041),加速了足细胞氧化应激的发生(12小时的时候达到高峰,t^(12h-DHE)=2.547,P^(12h-DHE)=0.042,t^(12h-TBA)=3.689,P^(12h-TBA)=0.022)。结论 AngⅡ诱导了SM22α功能失调,SM22α磷酸化后活化p47^(phox),揭示了SM22α在足细胞的氧化应激中起到了重要作用。
Objective Oxidative stress is the main cause of podocyte apoptosis, and accelerates the disease course of chronic kidney disease. However, the mechanism of podocyte apoptosis by oxidative stress remains elusive. Here we investigated the induction of oxidative stress in podocytes through the phosphorylation of p47phox by smooth muscle 22 alpha （SM22α） to regulate angiotensinⅡ（AngII）. Methods The expression of SM22α, p47phox and other proteins in normal podocytes and podocytes stimulated with AngII were measured by quantitative real time PCR and western blot. Changes of p47phox expression was evaluated under the knockdown of SM22α expression. Results After the stimulation of AngII for 12 hours, SM22α mRNA in podocytes decreased significantly （t=2.215, P=0.041）, while p47phox mRNA increased significantly （t=3.955, P =0.025）; the down-regulation of SM22α （t=2.215, P=0.041） prompted oxidative stress in podocytes and the oxidative stress reached the peak after 12 hours （tDHE=2.547, PDHE=0.042; tTBA=3.689, PTBA=0.022）. Conclusion AngII induced the dysfunction of SM22α and the phosphorylation of SM22α activated p47phox, which suggests that SM22α plays important role in the oxidative stress in podocytes.
出处
《中国血液净化》
2017年第9期601-606,共6页
Chinese Journal of Blood Purification
基金
黑龙江省科技厅资助项目(LC2012C22)
