罗布麻宁减轻衰老小鼠耳蜗带状突触氧化损伤  

Cochlear ribbon synapse oxidative damage attenuated by apocynin in aging mice

作　　者：刘成[1] 陈锡铭 彭梦萍 罗佳祺 高进良[1] LIU Cheng;CHEN Ximing;PENG Mengping;LUO Jiaqi;GAO Jinliang(Department of Otorhinolaryngology,Shenzhen Baoan Women and Children’s Hospital,Shenzhen,518102,China)

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

出　　处：《中国中西医结合耳鼻咽喉科杂志》2025年第1期1-5,共5页Chinese Journal of Otorhinolaryngology in Integrative Medicine

基　　金：广东省医学科学技术研究基金项目(No.B2023169)。

摘　　要：目的 观察NADPH氧化酶抑制剂罗布麻宁(apocynin,APO)对衰老小鼠耳蜗带状突触氧化损伤的保护作用。方法 36只雄性C57BL/6J小鼠(5周龄)分为三组(每组12只)。空白对照组小鼠项背部皮下注射生理盐水,D-gal组小鼠项背部皮下注射1000mg/kg D-gal,D-gal+APO组小鼠项背部皮下注射1000mg/kg D-gal和腹膜内注射50mg/kg APO,均每日1次,连续注射6周。造模结束后,90d B SPL声强下听性脑干反应(ABR)检测各组小鼠I波幅值以评估听功能;然后获取耳蜗组织,酶化学法检测小鼠耳蜗NADPH氧化酶活性和H_(2)O_(2)水平,免疫组织化学染色检测耳蜗DNA氧化损伤产物8-羟基-2-脱氧鸟苷(8-OHd G)及Ct BP2标记的内毛细胞带状突触突触前蛋白活性。结果 与空白对照组相比较,D-gal组小鼠ABR I波幅值显著降低,潜伏期显著延长;NADPH活性和H_(2)O_(2)水平显著升高,8-OHd G显著增加,Ct BP2计数显著减少。与D-gal组相比较,D-gal+APO组小鼠ABR I波幅值显著升高,潜伏期显著缩短,NADPH氧化酶活性和H_(2)O_(2)水平显著降低,耳蜗内毛细胞线粒体8-OHd G显著降低,Ct BP2计数显著增加。各指标差异水平均具有显著性统计学意义(P<0.01)。结论 NADPH氧化酶抑制剂罗布麻宁可有效减轻小鼠衰老过程中耳蜗带状突触的氧化损伤而对听功能发挥保护作用。Objective To investigate the attenuating effect of NADPH oxidase inhibitor apocynin(APO)on oxidative damage of cochlear ribbon synapse in D-galactose(D-gal)-induced aging mice.Methods In this experimental study,36 C57BL/6J mice at the age of 36 five-weeks were used to prepare aging mode with aging-associated hearing loss,randomly divided into 3 groups,with 12 in each.Mice in blank control group(BCG)were injected with 0.9%normal saline on the back of neck subcutaneously,those in modeling group(MG)injected with D-gal at a dose of 1000mg/kg in the same site as that in BCG subcutaneously,and ones in treating group(TG)injected with D-gal at a dosage of 1000mg/kg in the same site as those above subcutaneously plus APO injected at a dosage of 50 mg/kg intraperitoneally,all being once a day and lasted for 6 weeks.Once the model prepared successfully,auditory function of all mice was evaluated by auditory brain response(ABR),and then,all these animals were put into death to collect tissue samples from their cochlear for determination on the levels of NADPH oxidase activity and H_(2)O_(2) by enzymatic chemistry,and the expressive activity of DNA oxidative damage biomarker 8-hydroxy-2-deoxyguanosine(8-OHdG)as well as the numbers of carboxyl-terminal binding protein 2(CtBP2)-labeled cochlear ribbon synapse by immunohistochemical assay,tested and analyzed in a comparative way for their difference evaluation.Results Taking the data collected from animals of BCG as the baseline,mice in MG showed significantly decreased amplitude and delayed latency of ABR-wave I at 90dB SPL level,markedly elevated levels of NADPH oxidase activity,H_(2)O_(2) concentration and 8-OHdG value,while their numbers of cochlear ribbon synapse were obviously decreased.When compared with these data of MG,animals in TG were seen with obviously elevated amplitude and shorten latency of ABR-wave I at 90dB SPL level,significantly decreased levels of NADPH oxidase activity,H_(2)O_(2) concentration and 8-OHdG value,while their numbers of cochlear ribbon synapse

关 键 词：老年性聋 耳蜗带状突触 氧化损伤 罗布麻宁 保护效应 

分 类 号：R28[医药卫生—中药学]