大蒜素对D-半乳糖致衰老小鼠心脏和肺的保护作用∗

摘要

Objective To observe protective effects of allicin on heart and lung in aging mice induced by D-galactose, and try to explore the possible mechanism from the aspect of oxidative stress. Methods Fifty male Kunming mice were randomly divided into 5 groups:normal control group ( group C) ,model control group ( group D) and high-,middle-and low-dose of allicin groups ( H,M,L group) . The rats in group D,L,M and H were injected with D-galactose. At the same time,the rats in group L,M and H were injected with allicin. All of the injection lasted for 6 weeks. After that,athletic ability of the mice was evaluated by behavioral experiments. Malondialdehyde ( MDA ) content, superoxide dismutase ( SOD ) activity and total antioxidant capacity ( T-AOC) in the homogenate of heart and lung tissues were measured,and the expression levels of Bax and Bcl-2 were tested in heart and lung. Results Behavioral experiment showed that standing time on Rota Rod System and continuous running time on mice treadmill were significantly shortened in group D as compared with group C ( P<0.05) ,but those were prolonged in the allicin groups. Compared with group C,MDA content in homogenate of myocardium and lung tissues was significantly increased in group D (P<0.05),the activity of SOD was decreased (P<0.05) and T-AOC was decreased (P<0.05) . As compared with group D,MDA content in allicin groups was significantly decreased ( P<0.05) ,SOD activity increased (P<0.05) and A-TOC increased (P<0.05) in a dose-dependent manner. The results of immunohistochemistry showed that the expression of Bax was significantly increased in group D as compared with group C,and the expression of Bcl-2 was decreased. After the intervention of allicin,expression of Bax was decreased in group L,M and H as compared with group D, and expression of Bcl-2 was increased as compared with group D. Expression levels of Bax and Bcl-2 in lung tissues showed the same changing trend. Conclusion Allicin has a potential protect role on heart and lung in D-galactose-induced aging mice by increasing athletic ability,decreasing oxidative stress and decreasing cell apoptosis of myocardium and lung tissues.%目的：观察大蒜素对D-半乳糖致衰老小鼠心肌和肺组织氧化应激与细胞凋亡的影响，并初步探讨其作用机制。方法雄性昆明小鼠50只，按体质量随机分为正常对照组(C组)、模型对照组(D组)和大蒜素小剂量组(L组)、中剂量组(M组)、大剂量组(H组)，每组10只。 D、L、M、H组小鼠注射D-半乳糖0.9％氯化钠溶液制备衰老模型，L、M和H组同时腹腔注射大蒜素注射液进行给药干预，共持续6周。通过小鼠转棒疲劳仪和小鼠跑台检测各组小鼠运动耐力；检测心肌和肺组织匀浆上清液中丙二醛( MDA)含量、超氧化物歧化酶( SOD)活性及总抗氧化力( T-AOC)；免疫组织化学法观察凋亡相关蛋白Bax和Bcl-2表达并统计二者比值变化。结果行为学实验结果：与C组比较，D组小鼠在疲劳转棒上的停留时间和小鼠跑台上持续跑步时间均明显缩短( P<0.05)，L、M、H组较D组有所延长；D组小鼠心肌和肺组织匀浆上清液中MDA含量较C组升高( P<0.05)，SOD活性下降( P<0.05)，T-AOC下降( P<0.05)，L、M、H组较D组小鼠心肌和肺组织匀浆中MDA含量下降(P<0.05)，SOD活性升高(P<0.05)，T-AOC上升(P<0.05)，且呈现一定剂量效应关系；免疫组化结果显示：D组小鼠较C组小鼠心肌Bax表达增强，Bcl-2表达减弱，L、M、H组小鼠Bax表达较D组减弱，Bcl-2表达较D组增强，肺组织两蛋白表达趋势同心肌组织。结论大蒜素对D-半乳糖致衰老小鼠心脏和肺具有保护作用，具体表现为增加衰老小鼠心肺运动耐力、减轻心肌和肺局部组织过氧化水平，并减少心肌和肺组织内的细胞凋亡。