黄芪预处理对大鼠肠系膜缺血/再灌注损伤的影响及机制

Effects and mechanism of astragalus on mesentery in ischemia-reperfusion rats

关键词:  黄芪预处理  肠系膜  缺血再灌注  影响  机制

Key words:  astragalus pretreatment  mesentery  ischemia-reperfusion  effect  mechanism

摘要:

[目的] 研究黄芪预处理对大鼠肠系膜缺血/再灌注损伤的影响并探讨其机制。[方法] 取120只实验用大鼠随机分为假手术组、模型组、银杏叶提取物（3.15mg/kg）预处理组和黄芪（5、10、20g/kg）预处理组，每组20只，术前7d开始腹腔注射给药（每日1次），采用夹闭肠系膜上动脉45min的方法制备肠系膜缺血再灌注大鼠模型。再灌注2h后，取肠组织观察并测定肠组织含水量，苏木精-伊红（HE）染色观察肠组织形态结构变化并进行Chiu's评分。检测肠组织中抗氧化酶[超氧化物歧化酶（SOD）、过氧化氢酶（CAT）]活性、丙二醛（MDA）含量、C反应蛋白（CRP）、肿瘤坏死因子（TNF-α）、白介素-1β（IL-1β）、白介素-6（IL-6）、白介素-10（IL-10）含量、细胞凋亡状况并计算凋亡指数（AI）、半胱氨酸天冬氨酸蛋白酶3（Caspase-3）和半胱氨酸天冬氨酸蛋白酶9（Caspase-9）活性、NF-κB蛋白表达并进行半定量分析。[结果] 与模型组比较，黄芪预处理组大鼠肠组织外观明显红润、水肿状况明显改善，肠组织病变明显较轻。黄芪（10、20g/kg）预处理组肠组织含水量显着降低，Chiu's评分显着低于模型组，肠组织中SOD、CAT活性显着升高且MDA含量显着降低，CRP、TNF-α、IL-6含量显着降低，其中20g/kg预处理组IL-1β含量显着降低且IL-10含量显着升高。黄芪预处理各组肠系膜细胞凋亡状况明显较轻，其中黄芪（10、20g/kg）预处理组AI显着降低，肠组织中Caspase-3、Caspase-9活性显着降低、NF-κB蛋白表达显着下调，上述差异均具有统计学意义（P<0.05或P<0.01）。[结论] 黄芪预处理具有抑制大鼠肠系膜缺血/再灌注损伤的作用，其作用机制可能与黄芪能够降低氧化应激损伤、抑制炎症反应和细胞凋亡有关。

Abstract:

[Objective] To investigate the effects and mechanism of astragalus on mesentery in ischemia-reperfusion rats. [Methods] The 120 excremental rats were randomly divided into six groups: sham operation group, model group, Ginkgo biloba extract (GB, 3.15 mg/kg) pretreatment group and astragalus (5, 10, 20 g/kg) pretreatment groups. Severn days before surgery, the drugs were given by intraperitoneal injection, once a day. The rat models were made by clipping superior mesenteric artery. Two hours later, the appearance of mesentery tissue was observed and the water content was detected. The histopathological changes of mesentery tissue was observed by HE staining and the Chiu's score was detected, the activity of SOD, CAT and the contents of MDA in mesentery tissue were detected. The levels of CRP, TNF-α, IL-1β, IL-6 and IL-10 in mesentery tissue were detected. Tthe apoptosis of mesentery cells was observed by TUNEL staining and the apoptosis index(AI) was calculated. The activity of Caspase-3 and Caspase-9 in mesentery tissue were detected, and the expression of NF-κB was detected by Western Blot. [Results] Compared with model group, the appearance of mesentery tissue in astragalus pretreatment groups were improved, and the water content in astragalus (10, 20 g/kg) pretreatment groups were significantly decreased The histopathological changes of mesentery tissue in astragalus pretreatment groups were significantly improved. The Chiu's score in astragalus (10, 20 g/kg) pretreatment groups were significantly decreased. The activity of SOD and CAT in mesentery tissue was significantly increased and the contents of MDA were significantly decreased. The level of CRP, TNF-α and IL-6 in mesentery tissue of astragalus (10, 20 g/kg) pretreatment groups were significantly decreased, and the level of IL-1β in 20 g/kg pretreatment group was significantly decreased and the IL-10 was significantly increased. The mesentery cells apoptosis in astragalus pretreatment groups were significantly improved and the AI in astragalus(10, 20 g/kg) pretreatment groups was significantly decreased and the activity of Caspase-3, Caspase-9 in mesentery tissue were significantly decreased, and the expression of NF-κB was significantly decreased; all of the difference above were significant (P<0.05 or P<0.01). [Conclusion] Astragalus had inhibitive effects on mesentery in ischemia-reperfusion rats, which perhaps related to its effects of enhancing the activity of depressing oxidative stress, inhibiting inflammation and apoptosis.