Expression and significance of microRNA-21 in acute kidney injury renal of mice / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the expression and significance of microRNA - 21(miR - 21)in acute kidney injury mice model at the different time points following ischemic/ reperfusion. Methods C57BL/ 6J mice were divided into 3 major groups:the control group(C group),sham operation group(S group)and ischemia - reperfusion group(IR group). Later 2 groups were divided into 9 sub - groups respectively according to the time following reperfu-sion. Automatic biochemical analyzer detected serum creatinine(Scr),blood urea nitrogen(BUN)level. HE staining detected renal pathological damage. Renal tubulointerstitial pathological score accessed pathological damage. Real time - PCR tested the expression of miR - 21 and mitogen - activated protein kinase kinase 3(MKK3)mRNA in renal respectively. Immunohistochemistry staining tested expression of MKK3. Results IR group's Scr,BUN levels gradually increased following reperfusion,24 h reached its peak,then gradually declined. The Scr,BUN level had statistically sig-nificant difference between IR group and S group at the same time subgroup from 3 h to 168 h following reperfusion(all P ﹤ 0. 01). The change of kidney damage and pathological changes of interstitial and tubular injury score consensus with renal function. miR - 21 increased gradually in renal ischemia after reperfusion,24 h peaked and then stabilized at this high level. miR - 21 was positively correlated with pathological tubulointerstitial injury from 0 h to 168 h after reperfu-sion(r = 0. 969,P ﹤ 0. 05). IR group's MKK3 mRNA and protein expression rose sharply following ischemia/ reperfu-sion,24 h peaked,and then gradually decreased. From 3 h to 168 h,the expression of MKK3 mRNA and proteins had significant difference at each same time points subgroups between IR group and S group(all P ﹤ 0. 01). Conclusions miR - 21 increases gradually in renal ischemia after reperfusion,24 h peaked and then stabilized at this high level. miR - 21 is positively correlated with pathological tubulointerstitial injury,which may be associated with the negative regulated relationship between miR - 21 and MKK3.