复方健耳剂干预小鼠老年性耳蜗感音神经细胞凋亡径路

Exploration and discussion of compound healthy ear agent on interfering in age-related cochlear sensorineural apoptotic pathway

目的探讨中药复方健耳剂干预老年性耳蜗感音神经细胞凋亡作用可能径路。方法选择刚断奶C57BL/6J小鼠15只随机分为2月龄对照组、7月龄对照组、7月龄中药组各5只,其中2月龄对照组、7月龄对照组每日饮用自来水直到出生后2、7个月止,7月龄中药组每日饮用中药复方健耳剂直到出生后7个月止。各组期满立刻取出耳蜗,利用实时聚合酶链反应技术,检测耳蜗Fas配体(L)、细胞色素(cyt) C基因、含半胱氨酸的天冬氨酸蛋白水解酶(caspase)-3表达量。结果 7月龄对照组耳蜗cyt C、Fas L、caspase-3表达量均显著高于7月龄中药组和2月龄对照组(P<0. 05)。结论 C57BL/6J小鼠老年性耳蜗感音神经细胞凋亡可能均通过线粒体或细胞膜途径介导caspase引起程序性细胞死亡。该中药防治老年性聋关键作用机制之一可能与保护线粒体,防止cyt C外泄或稳定细胞膜,抑制Fas L,以阻止其触发caspase引起细胞程序性死亡径路有关。

Objective To investigate possible pathway on effects of compound healthy ear agent(CHEA)from traditional Chinese medicine(TCM)on interfering in age-related cochlear sensorineural apoptosis.Methods 15 C57 BL/6 J mice at 4 weeks of age were randomly divided into three groups.Five animals drank tap water daily from ablactation till 2 months of age and terminated as 2-month old control group.Five animals drank tap water daily from ablactation till 7 months of age and terminated as 7-month old control group with presbycusis.Other five animals drank the CHEA TCM daily from ablactation till 7 months of age as CHEA treating group.The animal cochleae in each group at the termination of the experiment were immediately removed and then were used for detecting cyt C,Fas L and caspase-3 in the cochlear tissue by Real Time PCR technique.In the end,the data were statistically analyzed and compared.Results Cycs,Fas L and caspase-3 expression were higher in 7-month old control group than those in 2-month old control group or in CHEA treating group(P<0.05).Conclusions Age-related cochlear sensorineural apoptosis in C57 BL/6 J mouse is probably via caspase-inducing programmed cell death mediated by two pathways from mitochondrion and cell membrane.One of mechanisms of the key effects of the CHEA on preventing and treating presbycusis is perhaps related mainly to protecting mitochondria and preventing cytochrome C leakage,or stabilizing cell membrane and inhibiting Fas L and then preventing them triggering programmed cell death pathway.