Fst通过调节IκBα/NF-κB信号通路减轻耳蜗炎症和氧化应激

Fst attenuates Cochlear Inflammation and Oxidative Stress Via regulating the IκBα/NF-κB Signaling Pathway

目的探讨卵泡抑素(follistatin,Fst)在耳蜗基底膜损伤中抗炎抗氧化应激的作用及机制。方法利用新霉素损伤耳蜗毛细胞模型,过表达Fst,采用RT-PCR检测各组Fst的表达,荧光显微镜下观察免疫荧光染色结果,并计数毛细胞变化情况,ELISA检测TNF-α、IL-1β、IL-6炎症因子的含量,Western Blot检测氧化应激指数、IκBα、NF-κB p65的变化及下游靶点的表达。结果新霉素损伤模型组中基底膜毛细胞受损明显,过表达Fst后,其中圈毛细胞数量部分逆转(P<0.05),而底圈无明显改善(P>0.05)。模型组中TNF-α、IL-1β、IL-6、iNOS和COX-2的表达量增加,过表达Fst可明显降低。在细胞浆中,模型组IκBα、NF-κB p65降低,过表达Fst后明显升高。P-IκBα在模型组明显升高,Fst过表达后降低。在细胞核内,模型组NF-κB p65显著升高,Fst过表达可部分逆转这一变化。结论Fst可能是通过调节IκBα/NF-κB信号通路减轻耳蜗炎症和氧化应激过程,保护耳蜗毛细胞。

Objective To investigate influence of follistatin(Fst)on inflammation and oxidative stress in cochlear basement membrane injury and the mechanisms.Methods In a model of neomycin induced cochlear basement membrane tissue injury,Fst expression was detected by RT-PCR.Changes of hair cells were observed under a fluorescence microscope with immunofluorescence staining.Inflammatory factors TNF-α,IL-1βand IL-6 were detected by ELISA.Oxidative stress index,IκBα,NF-κB P65 and expression of downstream targets were detected by Western Blot.Results Basement membrane hair cells were significantly damaged with neomycin injury.With Fst overexpression,hair cells conditions were significantly improved in the basal turn and partially preserved in the middle turn(P<0.05).Expression of TNF-α,IL-1β,IL-6,iNOS and COX-2 was increased with neomycin injury,while that of Fst was significantly decreased.with decreased IκBαand NF-κB P65 in the cytoplasm,which were reversed following overexpression of Fst.P-IκBαalso increased with neomycin injury,while was reversed after overexpression of Fst.In the nucleus,NF-κB P65 was significantly increased with neomycin injury and partially reversed by Fst overexpression.Conclusion Fst may reduce cochlear inflammation and oxidative stress and protect cochlear hair cells by regulating the IκBα/NF-κB signaling pathway.