摘要目的:评价微小核糖核酸-10a(miRNA-10a)在小鼠肾缺血再灌注损伤中的作用及其与转化生长因子β 1(TGF-β 1)/SMAD家族成员2(Smad2)信号通路的关系。 方法:SPF级健康成年雄性C57BL/6小鼠24只，8～10周龄，体重20～25 g，采用随机数字表法分为4组( n＝6)：假手术组(S组)、肾缺血再灌注组(IR组)、肾缺血再灌注+miRNA-10a拮抗剂组(I组)和肾缺血再灌注+miRNA-10a激动剂组(M组)。采用夹闭左侧肾蒂45 min后恢复灌注的方法制备小鼠肾缺血再灌注模型。M组和I组术前72 h时分别尾静脉注射miRNA-10a拮抗剂和激动剂20 nmol，1次/24 h，连续3次，S组和IR组给予等容量生理盐水。于再灌注24 h时采集眶静脉血样，检测血清肌酐(Scr)和BUN浓度。随后处死小鼠取肾组织，测定肾组织MDA含量和SOD活性，采用ELISA法测定IL-1β和TNF-α含量，采用Western blot法检测TGF-β 1和磷酸化Smad2(p-Smad2)的表达，光镜下观察病理学结果并计算肾小管损伤评分。 结果:与S组比较，IR组、I组和M组血清Scr、BUN浓度、肾组织MDA、IL-1β、TNF-α含量和肾小管损伤评分升高，IR组和M组肾组织SOD活性降低，TGF-β 1和p-Smad2表达上调( P<0.05)；与IR组比较，I组血清Scr、BUN浓度、肾组织MDA、IL-1β、TNF-α含量和肾小管损伤评分降低，SOD活性升高，TGF-β 1和p-Smad2表达下调，M组血清Scr、BUN浓度、肾组织MDA、IL-1β、TNF-α含量和肾小管损伤评分升高，SOD活性降低，TGF-β 1和p-Smad2表达上调( P<0.05)；与I组比较，M组血清Scr、BUN浓度、肾组织MDA、IL-1β、TNF-α含量和肾小管损伤评分升高，SOD活性降低，TGF-β 1和p-Smad2表达上调( P<0.05)。 结论:miRNA-10a参与了小鼠肾缺血再灌注损伤的过程，与激活TGF-β 1/Smad2信号通路有关。

abstractsObjective: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.