天冬总皂苷对衰老大鼠心脏P16基因表达的影响

Effect of total saponins of Asparagus racemosus on expression of P16 gene in the heart of aging rats

目的:研究天冬总皂苷对衰老大鼠心脏的保护作用及其对P16基因表达的影响。方法:通过皮下注射D-半乳糖建立衰老大鼠模型的同时,以天冬总皂苷灌胃进行治疗;采用硫代巴比妥酸法和黄嘌呤氧化法分别测定血清和心脏组织中丙二醛(Malondialdehyde,MDA)含量和超氧化物歧化酶(Superoxide dismutase,SOD)活性;采用光镜观察各组大鼠心脏形态学改变;应用Real-time PCR检测各组心脏组织P16 mRNA的表达。结果:天冬总皂苷给药组与模型组相比,血清与心脏中SOD活性均明显增高、MDA含量显著降低(P<0.05),并呈剂量依赖性;模型组心肌细胞嗜酸性染色增强,心肌细胞数量未见明显改变,但可见部分心肌细胞体积增大,心肌细胞间质内结缔组织增生,给药组能有效改善上述改变;与模型组相比,给药组能够使大鼠心脏组织内的P16 mRNA表达下降(P<0.05)。结论:天冬总皂苷增加自由基清除酶活力、降低P16 mRNA的表达可能是其改善衰老大鼠心脏的机制之一。

Objective：To investigate the effect of total saponins of Asparagus on the expression of P16 gene in the heart of aging rats,and to discuss its mechanism.Methods：Rats were injected with D-galactose daily for the construction of aging rat models,then rats in model group were orally administered with total saponins of Asparagus.The contents of superoxide dismutase（SOD） and malondialdehyde（MDA） in the serum and the heart were measured by hydroxylamine and chromatometric methods.The morphological changes of the heart was observed by microscope.The expression of P16 mRNA in the heart was detected by Real-time PCR.Results：Compared with those in model group,the activity of SOD was significantly higher and the content of MDA was significantly lower in the serum and the heart in treatment group（P0.05）;the heart had obvious pathological injury;the expression of P16 mRNA in the heart of treatment group was decreased significantly（P0.05）.Conclusion：Total saponins of Asparagus can improve the heart＇s function among aging rats,which may associate with the increase of SOD content and decrease of P16 expression.