Effect of Electroacupuncture at Tinggong and Yifeng on D-galactose-induced Aging of Auditory Cortex through SIRT1/PGC-1α Pathway in Guinea Pigs / 听力学及言语疾病杂志

ABSTRACT

Objective To investigate the role of SIRT1/PGC-1α pathway in the auditory cortex aging of guinea pigs with age-related hearing loss and whether the electroacupuncture can delay aging process of the auditory cortex in the aged guinea pigs induced by D-galactose through the regulation of SIRT1/PGC-1α pathway.Methods Thirty 4-month-old guinea pigs were randomly divided into three groups including the control group (n=10),D-galactose group (model group,n =10),and D-galactose and electroacupuncture group (electroacupuncture group,n =10).The elderly group (n=10) was composed of 18-month-old guinea pigs.The guinea pigs in model group and electroacupuncture group had been subcutaneously injected with D-galactose(300 mg· kg-1· d-1)for 6 weeks.Moreover,the guinea pigs in electroacupuncture group electroacupunctured at Tinggong and Yifeng for 15 minutes half an hour later once a day.After 6 weeks,the ABR threshold of guinea pigs in each group was detected.The mRNA and protein expression of SIR1 and PG-C-1α in auditory cortex of guinea pigs were detected by real -time fluoreacence quantitative PCR and Western Blot.Results There was a significant increase in the ABR threshold of the model group and elderly group (P＜0.001,compared with the control group),decrease in the electroacupuncture group (P＜0.001,compared with the model group),and no significant difference between model group and elderly group(P＞0.05).There was significant decrease in the expression of SIRT1 and PGC-1α in the model groupand elderly group(P＜0.05,compared with the control group),and significant increase at mRNA and protein levels in the electroacupuncture group (P＜0.05,compared with the model group).Conclusion SIRT1/PG-C-1α pathway may play a role in aging process of the auditory cortex in the aged guinea pigs induced by D-galactose,and electroacupuncture at Tinggong and Yifeng may increase the antioxidant capacity of auditory cortex by activating SIRT1/PGC 1α in guinea pigs with age-related hearing loss,thus delaying the aging process of auditory cortex.