摘要
目的探讨梓醇对D-半乳糖诱导的衰老大鼠血管内皮细胞的保护作用及对内皮细胞凋亡率及凋亡相关基因Bcl-2、Bax、Caspase-3表达的影响。方法选取3月龄Wistar大鼠32只,随机抽取8只作为正常组,余24只腹腔注射D-半乳糖复制衰老模型。造模成功后随机分为模型组、低剂量组[梓醇5 mg/(kg·d)腹腔内注射]和高剂量组[梓醇10 mg/(kg·d)腹腔内注射]3组,每组8只。12周后处死大鼠。显微镜下观察大鼠主动脉血管内皮细胞的形态学改变; TUNEL法原位标记凋亡的血管内皮细胞,计算细胞凋亡率;免疫组化法检测大鼠主动脉血管内皮细胞Caspase-3蛋白的表达; RT-PCR法检测Bcl-2及Bax的表达,并计算Bcl-2/Bax的比值。结果 D-半乳糖所致衰老大鼠主动脉血管内皮细胞出现明显病理学改变,与模型组比较,梓醇低剂量组及高剂量组均能明显改善大鼠主动脉血管内皮细胞的病理损害。模型组主动脉血管内皮细胞凋亡率明显高于正常组(P <0.01),梓醇低剂量组与高剂量组细胞凋亡率均明显低于模型组(P <0.01)。模型组Bcl-2的表达量明显低于正常组(P <0.01),而高剂量组Bcl-2的表达量明显高于模型组;模型组Bax的表达量明显高于正常组(P <0.01),高剂量组明显低于模型组;模型组Bcl-2/Bax比值明显低于正常组,梓醇低剂量组与高剂量组均能明显提高Bcl-2/Bax比值,与模型组比较差异有统计学意义(P <0.05或P <0.01);模型组Caspase-3蛋白表达明显高于正常组,而低剂量组与高剂量组Caspase-3蛋白表达均明显低于模型组(P <0.01)。结论梓醇能保护D-半乳糖所致衰老大鼠主动脉血管内皮细胞的形态学损害。梓醇的抗衰老作用可能与梓醇能抑制主动脉内皮细胞促凋亡基因Bax及Caspase-3的表达,促进抗凋亡基因Bcl-2的表达,同时上调Bcl-2/Bax比值有关。提示梓醇能抑制D-半乳糖诱导的衰老大鼠的血管内皮细胞凋亡,从而起到保护血管内皮细胞、延缓衰老的作用。梓醇的抗血管衰老作用呈现一定的剂量依赖性。
Objective To investigate the the protective effect of catalpol on the vascular endothelial cells in the aging rats,and explore the effect of catalpol on the apoptosis rate and expression of apoptosis related genes Bcl 2,Bax and Caspase 3. Methods Thirty two three months old wistar rats randomly divided into normal group （ n =8） and the aging rat model group （ n = 24）.The aging rat model was established by intraperitoneal injection of D galactose.After the model was successfully established,the rats in model group were randomly divided into model group （ n =8）,catalpol low dose group （ n =8）,and catalpol high dose group （ n =8）.The rats were treated with intraperitoneal injection of sterol 5 and 10 mg/（kg·d） in catalpol low dose group and catalpol high dose group for 12 weeks,respectively.The rats were sacrificed.The morphological changes of the aortic endothelial cells were observed under microscope.The terminal deoxynu cleotidyl transferase mediated dUTP nick end labelling （TUNEL） method was used to detect the apoptotic vascular endothelial cells in situ,and the apoptosis rate was calculated.The expression of Caspase 3 protein in aortic vascular endothelial cells was detected by immunohistochemistry.The expression of Bcl 2 and Bax was detected by reverse transcription polymerase chain reaction （RT PCR）.The ratio of Bcl 2/Bax was calculated. Results Compared with model group,the pathological changes of D galactose induced aortic vascular endothelial cells were obvious in model group.The pathological damages were significantly improved in catalpol low dose group and catalpol high dose group.The apoptosis rate of aortic endothelial cells in the model group was significantly higher than that in the normal control group.The apoptosis rate in catalpol low dose group and catalpol high dose group was significantly lower than that in the model group（ P 〈0.01）.The expression of Bcl 2 in the model group was significantly lower than that in the normal control group（ P 〈0.01）,which was significantly higher in catalpol high dose group than that in the model group（ P 〈0.01）.The expression of Bax in the model group was significantly higher than that in the normal control group（ P 〈 0.01）,which was significantly lower in catalpol high dose group than that in the model group（ P 〈0.01）.The Bcl 2/Bax ratio in the model group was significantly lower than that in the normal control group.The ratio of Bcl 2/Bax significantly increased in catalpol low dose group and catalpol high dose group（ P 〈0.05 or P 〈0.01）.The expression of Caspase 3 protein in the model group was significantly higher than that in the normal control group,which was significantly lower in catalpol high dose group than that in the model group（ P 〈0.01）. Conclusion Catalpol can significantly protect the morphological damage of aortic vascular endothelial cells in aging rats induced by D galactose.The anti aging effect may be related to the inhibition of the expression of Bax and Caspase 3 in aortic endothelial cells,and the up regulation of anti apoptotic gene Bcl 2 expression and BCL 2/Bax ratio.This study suggests that catalpol can inhibit the apoptosis of vascular endothelial cells induced by D galactose in aging rats, thereby protecting vascular endothelial cells and delaying aging.The anti vascular aging effect of catalpol has a dose dependent effect.
作者
曹萍
程梦馨
沈丹
钟亚
李夏
Cao Ping;Cheng Mengxin;Shen Dan;Zhong Ya;Li Xia(Zhongnan Hospital,Wuhan University,Wuhan 430071,Hubei,China)
出处
《中西医结合心脑血管病杂志》
2018年第18期2630-2634,共5页
Chinese Journal of Integrative Medicine on Cardio-Cerebrovascular Disease
基金
湖北省武汉市科技局应用基础研究计划项目(No.2013062301)
