Role of miRNA-10a in renal ischemia-reperfusion injury in mice: the relationship with TGF-β 1/Smad2 signaling pathway / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the role of microRNA-10a (miRNA-10a) in renal ischemia-reperfusion (I/R) injury in mice and the relationship with transforming growth factor beta1 (TGF-β 1)/Smad2 signaling pathway. Methods:Twenty-four SPF healthy male adult C57BL/6 mice, aged 8-10 weeks, weighing 20-25 g, were divided into 4 groups ( n=6 each) by the random number table method: sham operation group (S group), renal I/R group (IR group), renal I/R plus miRNA-10a antagonist group (I group), and renal I/R+ miRNA-10a agonist group (M group). The mouse model of renal I/R was developed by clamping the left renal pedicle for 45 min followed by reperfusion in anesthetized animals.miRNA-10a antagonist and agonist 20 nmol were injected via the tail vein once every 24 h for 3 consecutive days starting from 72 h before surgery in group M and group I, respectively, while the equal volume of normal saline was given instead in S and IR groups.Blood samples were collected from the orbital vein at 24 h of reperfusion to determine the concentrations of the serum creatinine (Scr) and blood urea nitrogen (BUN). Then the mice were sacrificed, and the kidney tissues were taken for determination of the malondialdehyde (MDA) content and superoxide dismutase (SOD) activity, contents of interleukin-1 beta (IL-β) and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay), and expression of TGF-β 1 and phosphorylated Smad2 (p-Smad2) (by Western blot) and for microscopic examination of the pathological changes.The damage to the renal tubules was scored. Results:Compared with group S, the concentrations of Scr and BUN, contents of MDA, IL-1β and TNF-α in renal tissues and renal tubular damage score were significantly increased in IR, I and M groups, and the activity of SOD was significantly decreased, and the expression of TGF-β 1 and p-Smad2 was up-regulated in IR and M groups ( P<0.05). Compared with group IR, the concentrations of Scr and BUN, contents of MDA, IL-1β and TNF-α in renal tissues and renal tubular damage score were significantly decreased, the activity of SOD was increased, and the expression of TGF-β 1 and p-Smad2 was down-regulated in group I, and the concentrations of Scr and BUN, contents of MDA, IL-1β and TNF-α in renal tissues and renal tubular damage score were significantly increased, the activity of SOD was decreased, and the expression of TGF-β 1 and p-Smad2 was up-regulated in group M ( P<0.05). Compared with group I, the concentrations of Scr and BUN, contents of MDA, IL-1β and TNF-α in renal tissues and renal tubular damage score were significantly increased, the activity of SOD was decreased, and the expression of TGF-β 1 and p-Smad2 was up-regulated in group M ( P<0.05). Conclusions:miRNA-10a is involved in the process of renal I/R injury and is related to activation of TGF-β 1/Smad2 signaling pathway in mice.