白藜芦醇减轻衰老小鼠听皮层线粒体氧化损伤  

Resveratrol Attenuates Mitochondrial Oxidative Damage in the Auditory Cortex of Aging Mice

作　　者：高进良[1] 彭梦萍 刘成[1] 陈锡铭 GAO Jinliang;PENG Mengping;LIU Cheng;CHEN Ximing(Department of Otorhinolaryngology,Shenzhen Baoan Women and Children’s Hospital,Shenzhen 518102,China;Department of Hand and Foot Microsurgery,Huazhong University of Science and Technology Union Shenzhen Hospital,Shenzhen 518052,China)

机构地区：[1]深圳市宝安区妇幼保健院耳鼻咽喉科,深圳518102 [2]华中科技大学协和深圳医院手足显微外科,深圳518052

出　　处：《中华耳科学杂志》2023年第4期509-513,共5页Chinese Journal of Otology

基　　金：广东省医学科学技术研究基金项目(No.B2023169)。

摘　　要：目的研究沉默信息调节因子2相关酶1(sirtuin1,SIRT1)激动剂白藜芦醇对D-半乳糖诱导的衰老小鼠听皮层线粒体氧化损伤的作用。方法24只5周龄雄性C57BL/6J小鼠适应性喂养1周后随机分成3组(8只/组):①对照组:小鼠每日皮下注射生理盐水1次,连续6周;②D-半乳糖组:小鼠每日皮下注射1000mg/kg D-半乳糖1次,连续6周;③D-半乳糖+白藜芦醇组:小鼠每日皮下注射1000mg/kg D-半乳糖1次,饲料中添加白藜芦醇400mg/kg,连续6周。造模结束后,我们利用听性脑干反应(auditory brain response,ABR)检测各组小鼠听功能,利用免疫印迹检测各组小鼠听皮层SIRT1蛋白水平的表达,利用酶化学法检测H2O2水平和总超氧化物歧化酶(Total superoxide dismutase,T-SOD)活性,利用免疫组织化学检测DNA氧化损伤标记物8-羟基-2-脱氧鸟苷(8-hydroxy-2-deoxyguanosine,8-OHdG)的水平,利用透射电镜观察各组小鼠听皮层线粒体超微结构。结果和对照组相比较,D-半乳糖诱导的衰老小鼠90 dB SPL声强下ABR-I波幅值显著降低(P=0.000<0.01),ABR-I波潜伏期显著延长(P=0.004<0.01),听皮层组织中SIRT1蛋白表达显著降低(P=0.000<0.01),H2O2生成显著增加(P=0.000<0.01),T-SOD活性显著降低(P=0.000<0.01),线粒体DNA氧化损伤标记物8-OHdG显著增加(P=0.000<0.01),部分线粒体超微结构呈现空泡化。和D-半乳糖组相比较,D-半乳糖+白藜芦醇组小鼠90 dB SPL声强下ABR-I波幅值显著升高(P=0.012<0.05),ABR-I波潜伏期显著缩短(P=0.002<0.01),听皮层组织中SIRT1蛋白表达显著增加(P=0.000<0.01),H2O2生成显著减少(P=0.000<0.01),T-SOD活性显著增加(P=0.013<0.05),8-OHdG显著降低(P=0.000<0.01),线粒体超微结构基本正常,仅表现为电子密度降低。结论SIRT1激动剂白藜芦醇可有效减轻衰老过程中听皮层线粒体氧化损伤。Objective To investigate the effects of sirtuin1(SIRT1)agonist resveratrol(RSV)on mitochondrial oxidative damage in the auditory cortex of D-galactose(D-gal)-induced aging mice.Methods After acclimation for a week,24 five-week-old male C57BL/6J mice were randomly allocated into a control group(0.9%saline injected subcutaneously once a day for 6 weeks),a D-gal group(D-gal injected subcutaneously at 1000 mg/kg once a day for 6 weeks)and a D-gal+resveratrol(RSV)(dietary supplementation with 400 mg/kg RSV once a day in addition to D-gal for 6 weeks)(n=8 per group).Auditory function was evaluated by auditory brain responses(ABRs).SIRT1 protein in the auditory cortex was detected by western blot.The levels of H2O2 and total superoxide dismutase(T-SOD)activity were tested by enzymatic chemistry.The levels of 8-hydroxy-2-deoxyguanosine(8-OHdG),a biomarker of DNA oxidative damage,were analyzed by immunohistochemical methods.The ultrastructure of mitochondria in the auditory cortex was observed by transmission electron microscopy.Results Compared with the control group,the of ABR-wave I amplitude was significantly decreased(P=0.000<0.01)with prolonged latency(P=0.004<0.01)at 90 dB SPL in the D-gal group,who also showed decreased levels of SIRT1 protein in the auditory cortex(P=0.000<0.01)with increased H2O2 generation(P=0.000<0.01),decreased T-SOD activity(P=0.000<0.01),increased levels of 8-OHdG(P=0.000<0.01),as well as serious degeneration of mitochondria.Compared with the D-gal group,ABR-wave I amplitude were higher(P=0.012<0.05)and latency shorter(P=0.002<0.01)at 90 dB SPL in the D-gal+RSV group,with increased levels of SIRT1 protein(P=0.000<0.01),decreased H2O2 generation(P=0.000<0.01),increased T-SOD activity(P=0.013<0.05)and decreased levels of 8-OHdG(P=0.000<0.01)in the auditory cortex.Mitochondrial ultrastructure showed only reduced electron density in the D-gal+RSV group.Conclusion Our findings suggest that the SIRT1 agonist resveratrol can be an effective treatment against mitochondrial oxidative damage in the a

关 键 词：白藜芦醇 SIRT1 老年性聋 听皮层 线粒体氧化损伤 

分 类 号：R764[医药卫生—耳鼻咽喉科]