p38MAPK信号通路介导miR-21在缺血再灌注肾损伤中的作用机制  

Mechanism of p38MAPK signaling pathway mediating miR-21 in renal ischemia-reperfusion injury

作　　者：刘恋红 李志辉[1] LIU Lianhong;LI Zhihui(Hunan Children's Hospital,Changsha 410007,China)

机构地区：[1]湖南省儿童急性肾损伤临床医学研究中心,湖南省儿童医院肾脏风湿免疫科,长沙410007

出　　处：《中国中西医结合儿科学》2021年第6期468-472,F0003,共6页Chinese Pediatrics of Integrated Traditional and Western Medicine

基　　金：湖南省科技厅重点项目(2018SK2139)。

摘　　要：目的研究microRNA-21(简称miR-21)与p38MAPK信号通路在缺血再灌注(IR)肾损伤中的作用机制。方法以雄性C57BL/6J小鼠为研究对象,根据是否进行IR损伤将小鼠分为对空白对照组、IR组,假手术组及缺血预处理再灌注组(IPC+IR组)。按IR后不同时间点(0 min、5 min、30 min、45 min、2 h、12 h、24 h、48 h)各分为8个亚组,分析各组肾脏组织,miR-21水平及p38MAPK、p-p38MAPK蛋白表达水平及肾脏病理损害情况。结果(1)肾脏病理:空白对照组无明显肾脏损害;在IR组及假手术组中,小鼠在IR后逐渐出现了肾脏病理损害,24 h达高峰,之后逐渐恢复;缺血预处理后,IPC+IR组小鼠肾脏病理损害趋势与IR组平行,但各亚组损害程度均较IR组低,IPC+IR组与IR组、假手术组肾小管病理损伤评分组间比较差异有统计学意义(P<0.01)。(2)p38MAPK表达水平:各组的8个时间点相对表达水平(p38MAPK/β-actin)差异均无统计学意义(P>0.05)。(3)p-p38MAPK相对表达水平(p-p38MAPK/p38MAPK):在空白对照组中无明显表达;在IR组中,p-p38MAPK相对表达水平在IR 5 min后迅速增高,2 h达峰值,之后仍持续有较高水平表达。缺血预处理后,在IPC+IR组中,p-p38MAPK的相对表达水平趋势与IR组平行,2 h达峰值,但各亚组的表达相对水平均低于IR组、假手术组,各组组间差异有统计学意义(P<0.01)。(4)miR-21表达水平:在IR组中,随着IR时间的推移,miR-21在IR后5 min表达增高,24 h达高峰,为基线值的15.2倍,之后维持在较高水平,空白对照组miR-21水平表达无明显变化;缺血预处理后,IPC+IR组中,miR-21的表达水平在0~48 h各时间点均保持在IR组时的峰值,约为基线值14.8倍;与假手术组、IR组之间差异有统计学意义(P<0.01)。结论缺血预处理保护肾脏的可能机制是通过上调miR-21,抑制p38MAPK的磷酸化,从而减少p38MAPK信号通路下游相关炎性介质的表达而保护肾脏。Objective To study the functioning mechanism of microRNA-21(miR-21)and p38MAPK signaling pathway in renal injury of ischemia reperfusion(IR).Methods Male C57BL/6J mice were divided into four groups based on whether IR was performed:blank control group,IR group,sham operation group and ischemia preconditioning+ischemia reperfusion group(IPC+IR group).Then they were each divided to 8 subgroups according to different time points after IR(0min,5min,30min,45min,2h,12h,24h,48h).Analyze the renal tissue,miR-21 level,expression level of p38MAPK and p-p38MAPK protein,and pathological injury of kidney.Results(1)Pathology of kidney:there was no obvious renal injury in the blank control group;pathology injury of kidney gradually appeared after IR in IR group and sham-operation group,which peaked at 24h and gradually recovered;after ischemic preconditioning,the tendency of pathological injury of kidney in IPC+IR group was parallel to that in IR group,but the injury of each subgroup was milder than IR group,and there was statistical difference in the score of renal tubular pathological injury between IPC+IR group and IR and sham-operation group(P<0.01).(2)p38MAPK expression level:there was no statistical difference in the relative expression level(p-p38MAPK/β-actin)among the groups at the 8 time points(P>0.05).(3)The relative expression level of p-p38MAPK(p-p38MAPK/p38MAPK):there was no obvious expression in blank control group;in IR group,the relative expression level of p-p38MAPK increased rapidly at 15min after IR and peaked at 2h,and remained at a relatively high level afterwards.After ischemic preconditioning,the tendency of the relative expression level of p-p38MAPK in IPC+IR group was parallel to that in IR group,and the level peaked at 2h,but it was lower in each of the 8 subgroups than in the IR group and sham-operation group,the difference being statistical(P<0.01).(4)Expression level of miR-21:in IR group,with time passing,miR-21 expression increased at 5min after IR and peaked at 24h,being 15.2 times that of basel

关 键 词：急性肾损伤 MICRORNA-21 缺血再灌注损伤 缺血预处理 P38MAPK 

分 类 号：R725.9[医药卫生—儿科]