菟丝子醇提液对衰老模型小鼠肝线粒体保护作用的实验研究

The study protection of alcoholic extract of semen cuscutae on the hepatic mitochondria in aging model mice

目的探讨菟丝子醇提液对衰老模型小鼠肝脏线粒体的保护作用及机制。方法将纯系昆明种小鼠50只,随机分为青年组、衰老模型组、给药15d组、给药30d组和给药45d组。D-半乳糖制作衰老模型,经胃灌服菟丝子醇提液。采用比色分析法测定呼吸链复合体Ⅳ活性,PCR法检测线粒体DNA缺失,RT-PCR法检测COⅠmRNA的表达水平;同时观察不同给药天数对上述指标的影响。结果D-半乳糖可诱导小鼠肝线粒体呼吸链复合体Ⅳ活性降低(P<0.01),肝mtDNA的缺失增加,呼吸链复合体ⅣCOⅠ亚基mRNA的表达水平增高。菟丝子醇提液可提高呼吸链复合体Ⅳ活性,减少mtDNA缺失,降低呼吸链复合体ⅣCOⅠ亚基mRNA的表达。结论菟丝子醇提液可提高衰老模型小鼠呼吸链复合体Ⅳ活性,降低COⅠ亚基mRNA表达,减少mtDNA缺失,而发挥保护肝脏线粒体的作用,并随给药时间的延长作用更显著。

Objective By investigating the effect of alcoholic extract of semen cuscutae on the complex IV activities and expression of mRNA of subunit CO I of mitochondrial respiratory chain, DNA damage in liver of aging model mice to explain the protection and mechanism of alcoholic extract of semen cuscutae on hepatic mitochondrial of aging model mice. Methods 50 Kunming mice were randomly divid- ed into young, aging, three different administration group of 15, 30 and 45 d. Aging model mice were made by D-gal injection. The alcoholic extract of semen cuscutae was drenched by stomach at a dosage of 1.5 g/kg. Complex IV activities were detected by colorimetric analysis antigenic, mtDNA absence part was assayed by PCR method. Co I subunit express was examined on the mRNA level by RT-PCR. At the same time, the effect of administration of different days on these indexs were observed. Results Compared with the young group, the activity of complex IV of respiratory chain was decreased, the loss of mtDNA fragment was increased and the level of expression of mRNA of subunit CO I of respiratory chain was higher in aging model mice. The alcoholic extract of semen cuscutae increased the activity of complex IV of respiratory chain, decreased the loss of mtDNA and the expression of mRNA of submit CO I of respiratory chain. Conclusions The alco- holic extract of semen cuscutae educes the protection mitochondrial in liver by increasing the activity of complex IV and decreasing the loss of mtDNA and the Co I expression, having more significant effect with the administration prolongation.