cGAS-STING信号通路参与耳蜗毛细胞衰老  

cGAS-STING signal pathway participates in cochlear hair cell senescence

作　　者：孙颖 贺祖宏 陈雄 SUN Ying;HE Zuhong;CHEN Xiong(Dept.of Otorhinolaryngology,Head and Neck Surgery,Zhongnan Hospital of Wuhan University,Wuhan 430071,Hubei,China)

机构地区：[1]武汉大学中南医院耳鼻咽喉头颈外科,武汉湖北430071

出　　处：《武汉大学学报(医学版)》2025年第3期298-301,391,共5页Medical Journal of Wuhan University

基　　金：国家自然科学基金面上项目(编号:82271183)。

摘　　要：目的:探讨环化鸟苷酸-腺苷酸合成酶(cGAS)-干扰素刺激基因(STING)信号通路在衰老耳蜗毛细胞中的作用机制。方法:使用D-半乳糖(D-gal)诱导OC-1细胞衰老,采用不同浓度的D-gal处理OC-1细胞72 h,然后用CCK-8法检测细胞活力变化。将OC-1细胞分为对照(Control)组和D-gal组,β-半乳糖苷酶染色法检测是否成功建立细胞衰老模型。之后,流式细胞术检测线粒体活性氧(ROS)和线粒体膜电位水平,免疫荧光观察线粒体DNA(mtDNA)泄漏情况,Western Blot检测cGAS、STING、TANK结合激酶1(TBK1)、p-TBK1、核转录因子(NF)-κB p65亚基及p-p65表达水平。结果:使用不同浓度D-gal刺激OC-1细胞72 h后发现,当D-gal浓度高于10 mg·mL^(-1)时细胞活力逐渐下降(P<0.001),随后选择15 mg·mL^(-1)作为后续实验中D-gal组的处理浓度。与Control组相比,D-gal组细胞明显蓝染,线粒体ROS水平升高(P<0.01),线粒体膜电位降低(P<0.01),细胞中存在mtDNA泄漏。此外,相比Control组,D-gal组细胞cGAS和STING蛋白表达水平上调(P<0.05),p-TBK1/TBK1和p-p65/p65比值增加(P<0.05)。结论:cGAS-STING通路可能通过mtDNA易位而激活,进而参与老年性聋的发展进程。Objective:To investigate the mechanism of the cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway in aging cochlear hair cells.Methods:Cochlear hair cells OC-1 were induced to senescence using D-galactose(D-gal).OC-1 cells were treated with different concentrations of D-gal for 72 h,then the cell viability was assessed by using the cell counting kit8(CCK-8)assay.After OC-1 cells were divided into the Control and D-gal groups,theβ-galactosidase staining was adopted to verify the successful establishment of the cellular senescence model.Subsequently,flow cytometry was utilized to assess mitochondrial reactive oxygen species(ROS)and mitochondrial membrane potential levels,immunofluorescence was employed to observe mitochondrial DNA(mtDNA)leakage,and Western Blot was conducted to detect the expression levels of cGAS,STING,TANK-binding kinase 1(TBK1),phosphorylated TBK1(p-TBK1),nuclear factor(NF)-κB p65 subunit,and phosphorylated p65.Results:After treating OC-1 cells with various concentrations of D-gal for 72 hours,the CCK-8 assay results showed a gradual decline in cell viability when the concentration of D-gal exceeded 10 mg·mL^(-1)(P<0.001).Therefore,15 mg·mL^(-1) was chosen as the treatment concentration of the D-gal group in the subsequent experiments.Compared with the cells in the control group,cells in the D-gal group displayed prominent blue staining,elevated mitochondrial ROS levels(P<0.01),decreased mitochondrial membrane potential(P<0.01),and mtDNA leakage.Furthermore,the expression levels of cGAS and STING proteins were upregulated in the D-gal group(P<0.05),with increased ratios of p-TBK1/TBK1 and p-p65/p65(P<0.05).Conclusion:The cGAS-STING pathway may be activated through mtDNA translocation,thereby participating in the development process of age-related hearing loss.

关 键 词：cGAS-STING 老年性聋 线粒体DNA 

分 类 号：R764.3[医药卫生—耳鼻咽喉科]