大蒜素对大鼠溃疡性结肠炎淋巴细胞凋亡及其调控蛋白的影响

Effects of allitridi on lymphocyte apoptosis and its regulatory gene expression in rat ulcerative colitis

目的:通过观察大鼠溃疡性结肠炎淋巴细胞凋亡及其调控蛋白Bcl-2和Bax的表达及大蒜素对其的影响,探讨大蒜素(Allitridi,Alt)对溃疡性结肠炎肠黏膜的保护作用及其机制.方法:用三硝基苯磺酸(TNBS)建立大鼠溃疡性结肠炎模型.将动物随机分为空白对照组(Normalgroup)、三硝基苯磺酸组(TNBSgroup)、三硝基苯磺酸+生理盐水组(TNBS+NSgroup)、三硝基苯磺酸+大蒜素组(TNBS+Altgroup)四组.利用DNA缺口末端标记技术(TUNEL法)和Bcl-2、Bax蛋白免疫组化染色,分别检测溃疡性结肠炎大鼠肠组织中的淋巴细胞凋亡和淋巴细胞Bcl-2和Bax的表达,生化检测一氧化氮(NO)含量,并观察肠道大体形态和组织学改变.结果:和三硝基苯磺酸组相比,三硝基苯磺酸+大蒜素组中淋巴细胞凋亡增加(2.1±1.0vs5.9±2.0,P<0.01),Bcl-2表达阳性淋巴细胞减少及一氧化氮(NO)含量下降(10.0±2.5vs31.0±6.0,197±11vs523±40,P<0.01).损伤指数明显下降(1.6±0.5vs5.8±0.7,2.1±0.6vs6.1±0.6,P<0.01).结论:大蒜素可以通过促进淋巴细胞凋亡和清除NO自由基而对TNBS诱导的溃疡性结肠炎肠黏膜有保护作用.

AIM:To investigate the effects of Allitridi on lymphocyte apoptosis and its regulatory gene expression in rat ulcerative colitis. METHODS:Rat colitis model was induced by 2, 4, 6- trinitrobenzene sulfonic acid (TNBS). The apoptotic cells were visualized by TUNEL. Bcl-2 and Bax protein expression in colon tissue was examined by immunohistochemistry. Bio- chemistry was used to detect the nitrogen monoxide (NO) activity in the mucosa, At the same time, the macroscopical and histological changes of the colon were evaluated. RESULTS:In TNBS group, the content of nitrogen monoxide, the positive cell quantity of expression of Bcl-2 and the apoptotic cell quantity were higher than those in both nor- mal group and TNBS+Alt group (P <0.01), but Bax positive cell quantity was lower than that in normal group (P <0.01). CONCLUSION:Allitridi has protective effects on ulcerative colitis of rat by promoting apoptosis of lymphocytes in lamina propria and cleaning NO free radical.