姜黄素后处理对缺血再灌注肾损伤大鼠Notch2/Hes-1通路的影响*

Effects of curcumin-postconditioning on Notch2/Hes-1 pathway of renal injury induced by limb ischemia-reperfusion in rats*

摘要:

目的 探讨姜黄素后处理大鼠肢体缺血再灌注肾损伤对Notch2/Hes-1通路的影响。方法 选取成年雄性SD大鼠80只，体重280～320?g，6～8月龄，采用随机数字表法，将其分成4组（各20例）：假手术组（Sham组）、缺血再灌注组（I/R组）、姜黄素后处理组（I/R+Cur组）及抑制剂组（I/R+DAPT组）。采用夹闭双下肢股动脉4?h再灌注4?h复制肢体缺血再灌注肾损伤模型。在大鼠肢体缺血后4?h，I/R+Cur组经腹腔注射姜黄素200?mg/kg；I/R+DAPT组经腹腔注射DAPT 0.5?μmol。于再灌注4?h时经颈动脉取血，待检血浆肌酐、尿素氮、丙二醛等指标。随后处死大鼠，采用HE染色检测肾组织病理变化，并对肾小管间质进行半定量评分；应用Western blotting和RT-PCR分别测定Notch2受体蛋白和靶分子Hes-1 mRNA的表达；通过ELISA测定肾组织TNF-α及IL-1β的表达。结果 与Sham组比较，I/R组可见肾小管出现小管明显扩张，管腔内可见管型，刷状缘消失、肾间质炎症细胞浸润等病变，肾小管间质半定量评分升高（P?<0.05）；组织中Notch2、Hes-1 mRNA、TNF-α和IL-1β的表达升高（P?<0.05）；与I/R组比较，I/R+Cur组肾间质炎症细胞浸润减少，视野内未见肾小管扩张，偶可见少量管型等病理改变，肾小管间质半定量评分下降（P?<0.05）；组织中Notch2、Hes-1 mRNA、TNF-α和IL-1β的表达升高（P?<0.05）；I/R+DAPT组各指标与I/R+Cur组比较，差异无统计学意义（P?>0.05）。结论 姜黄素后处理可减轻大鼠肢体缺血再灌注时肾损伤，其作用机制可能与下调Notch2/Hes-1信号通路有关。

Abstract:

Objective To investigate the effects of curcumin-postconditioning on Notch 2/Hes-1 pathway of renal injury induced by limb ischemia-reperfusion in rats. Methods Eighty adult male Sprague-Dawley rats, aged 6 to 8 months, weighing 280 to 300?g, were randomly diviled into 4 group (n?=?20) by useing a random number table: sham group (group Sham); ischemia-reperfusion group (group I/R); curcumin-postconditioning group (group I/R+Cur) and Inhibitor group (group I/R+DAPT). Limb ischemia was induced by occlusion of bilateral femoral arteries for 4?h followed by reperfusion for 4?h in group I/R, group I/R+Cur and group I/R+DAPT. 4?h after ischemia, curcumin 200?mg/kg and DAPT 0.5?μmol was respectively injected by intraperitoneal pathway into group I/R+Cur and group I/R+DAPT, and the equal volume of normal saline was given in the other groups. Arteries blood samples were taken 4?h after reperfusion for examining biochemical indexes such as creatinine (Cr), blood urea nitrogen (BUN) and malonic dialdehyde (MDA) in plasma. Then the rats were sacrificed, and the kidneys were examined by HE staining to detect pathological changes and semi-quantitative score of renal tubulointerstitia (SSRT); the expression of Notch2 and Hes-1 mRNA were determined by western-blotting and RT-PCR in renal tissue; TNF-α and IL-1β were determined by ELISA in renal tissue. Results Compared with group Sham, HE staining showed obvious dilatation of renal tubules, tubular pattern, disappearance of brush border and infiltration of inflammatory cells in renal interstitium in group I/R (P??0.05). Conclusions Curcumin post-treatment can reduce the renal injury induced by limb ischemia and reperfusion in the rats and its mechanism may be related to the downregulation of Notch2/Hes-1 signaling pathway.