百里醌对大鼠肠缺血再灌注损伤的保护作用

Protective effects of thymoquinone on intestinal ischemia-reperfusion injury in rats

目的观察百里醌对大鼠肠缺血再灌注损伤(IIRI)的保护作用。方法 45只健康雄性SD大鼠,随机分成3组:假手术对照组(A组)、肠缺血再灌注组(B组)和肠缺血再灌注+百里醌组(C组)。B组和C组分别建立大鼠肠缺血再灌注模型,C组在再灌注同时腹腔注射百里醌(50mg/kg)。方法 HE染色观察小肠组织形态学改变;测定丙二醛(MDA)、超氧化物岐化酶(SOD)含量;采用原位缺口末端标记检测肠黏膜上皮细胞凋亡指数(AI);RT-PCR检测小肠组织中的caspase-3、Bax和Bcl-2的表达情况。结果 B组可见肠绒毛排列紊乱,肠黏膜坏死等表现,经百里醌治疗后明显改善;A组、B组和C组的凋亡指数分别为(4.53±0.28)%、(21.73±1.17)%、(9.53±0.96)%,SOD活性分别为(135.37±3.34)、(76.45±1.39)和(95.13±1.64)U/mg蛋白,MDA含量分别为(2.83±0.36)、(9.23±0.78)和(4.97±0.45)nmol/mg蛋白;与A组比较,B组中Bax、caspase-3mRNA表达水平明显增高,Bcl-2表达水平降低(P<0.05)。与B组比较,C组中Bcl-2表达水平增高,Bax、caspase-3表达水平减低(P<0.05)。结论百里醌可减轻氧化应激水平,发挥抗凋亡作用,从而在肠IIRI过程中发挥保护作用。

Objective To investigate the protective effect of thymoquinone on intestinal ischemia reperfusion injury in rats.Methods Forty-five male SD rats were randomly divided into Sham-operation control group(group A),ischemia reperfusion group(group B)and ischemia reperfusion+thymoquinone group(group C).Intestinal ischemia reperfusion model was established in group B and C.Thymoquinone(50 mg/kg)was injected intraperitoneally followed reperfusion in group C.The pathological changes of the intestine were observed by HE staining.MDA and SOD content were deter-mined.Cell apoptosis index was detected by dUTP nick end labeling.The expression of caspase-3,Bax and Bcl-2 in in-testinal tissue were detected by RT-PCR.Results Group B showed intestinal villus disorderly arrangement,intestinal mucosa epithelia necrosis thymoquinone treatment significantly improved the above changes.AI in group A,group B and groupC were(4.53±0.28)%,(21.73±1.17)%and(9.53±0.96)%,respectively.The SOD activities were(135.37±3.34),(76.45±1.39)and(95.13±1.64)U/mg,respectively.MDA were(2.83±0.36),(9.23±0.78)and(4.97±0.45)nmol/mg.Compared with group A,the mRNA expression of Bax and caspase-3 were significantly increased,and the mRNA expression of Bcl-2 was decreased in group B(P〈0.05).Compared with group B,the expression of Bcl-2 in was obvious increased,and the expression of Bax and caspase-3 decreased in group C(P〈0.05).Conclusion Thymoqui-none reduces the level of oxidative stress and inhibits the apoptosis.Thus,it plays a protective role in the process of intestinal ischemia-reperfusion injury.