敲减SET8表达通过上调p53/DRAM1信号通路促进大鼠血管平滑肌细胞自噬和凋亡  

Knockdown of SET8 promotes autophagy and apoptosis of rat vascular smooth muscle cells by up-regulating p53/DRAM1 signaling pathway

作　　者：刘兰[1] 张东雪[1] 朱荣芳[1] 李晖 梁向楠 张胜雷[1] 白亚玲[1] LIU Lan;ZHANG Dong-xue;ZHU Rong-fang;LI Hui;LIANG Xiang-nan;ZHANG Sheng-lei;BAI Ya-ling(Departments of Nephrology,the Fourth Hospital of Hebei Medical University,Shijiazhuang 050011,China)

机构地区：[1]河北医科大学第四医院肾内科,河北石家庄050011

出　　处：《中国病理生理杂志》2022年第3期427-433,共7页Chinese Journal of Pathophysiology

基　　金：河北省医学科学研究重点课题(No.20180513,No.20190702)。

摘　　要：目的:探讨赖氨酸甲基转移酶SET8(SET domain-containing protein 8)低表达通过p53/DRAM1(DNA damage-regulated autophagy modulator 1)通路调控大鼠血管平滑肌细胞(vascular smooth muscle cells,VSMCs)自噬和凋亡的作用及机制。方法:体外原代培养大鼠VSMCs,敲减SET8表达,将细胞分为3组:正常组、空载体对照组和SET8-shRNA组。流式细胞术检测细胞凋亡,MTT法检测细胞活力,Western blot检测SET8、p53、DRAM1、LC3、Bax和Bcl-2的蛋白水平。过表达DRAM1,将大鼠VSMCs分为3组:正常组、空载体对照组和DRAM1组。检测各组细胞活力,凋亡及DRAM1、LC3、Bax和Bcl-2的蛋白水平。敲减SET8表达的同时敲减p53或DRAM1表达,观察LC3、Bax和Bcl-2的蛋白表达情况。结果:(1)敲减SET8表达后,大鼠VSMCs凋亡显著增多,活力显著降低(P<0.05)。Western blot结果显示,敲减SET8表达后,SET8和Bcl-2表达显著降低(P<0.05),p53、DRAM1、LC3-II和Bax表达显著升高(P<0.05)。(2)过表达DRAM1后,大鼠VSMCs凋亡显著增多(P<0.05),活力显著降低(P<0.05)。Western blot结果显示,过表达DRAM1后,DRAM1、LC3-II和Bax表达显著升高(P<0.05),Bcl-2表达显著降低(P<0.05)。(3)敲减p53或DRAM1表达后,LC3-II和Bax表达降低,Bcl-2表达升高(P<0.05)。结论:敲减SET8表达可促进大鼠血管平滑肌细胞发生自噬和凋亡,可能机制是通过上调p53和DRAM1表达,促进自噬蛋白LC3-II及凋亡蛋白Bax表达实现的。AIM:To investigate whether lysine methyltransferase SET domain-containing protein 8(SET8)knockdown regulates the autophagy and apoptosis of rat vascular smooth muscle cells(VSMCs)through p53/DNA damageregulated autophagy modulator 1(DRAM1)signaling pathway.METHODS:Rat VSMCs were divided into 3 groups:normal group,vector group and SET8-shRNA group.Apoptosis was detected by flow cytometry,viability was detected by MTT,and the protein levels of SET8,p53,DRAM1,LC3,Bax and Bcl-2 were detected by Western blot.VSMCs of rats were divided into 3 groups:normal group,vector group and DRAM1 overexpression group.Cell viability,apoptosis and protein levels of DRAM1,LC3,Bax and Bcl-2 were detected.The protein expressions of LC3,Bax and Bcl-2 were observed in VSMCs of rats following suppression of p53 or DRAM1 while interfering with SET8.RESULTS:The apoptosis of VSMCs was increased significantly and viability was decreased significantly after SET8 knockdown(P<0.05).Western blot showed that the expressions of SET8 and Bcl-2 were decreased,and the expressions of p53,DRAM1,LC3-II and Bax were increased significantly after SET8 knockdown(P<0.05).Apoptosis of VSMCs was increased significantly and viability was decreased significantly after overexpression of DRAM1(P<0.05).Western blot showed that the expressions of DRAM1,LC3-II and Bax were increased and the expression of Bcl-2 was decreased after overexpression of DRAM1(P<0.05).The expressions of LC3 and Bax were decreased and the expression of Bcl-2 was increased after inhibiting the expression of p53 or DRAM1(P<0.05).CONCLUSION:Autophagy and apoptosis in vascular smooth muscle cells of rats were promoted by knockdown of SET8.The possible mechanism is to promote the expression of autophagy protein LC3-II and apoptotic protein Bax by upregulating the expressions of p53 and DRAM1.

关 键 词：血管平滑肌细胞 SET8蛋白 DRAM1蛋白 自噬 细胞凋亡 

分 类 号：R363.2[医药卫生—病理学] R543[医药卫生—基础医学]