DUSP1通过促进线粒体自噬相关变化保护HEI-OC1细胞免受D-半乳糖诱导的损伤

文献信息

中文摘要

引言： 双特异性磷酸酶1（DUSP1）已被证明与年龄相关性听力损失（ARHL）和线粒体自噬进展密切相关。然而，DUSP1在耳蜗毛细胞损伤中的功能及其潜在机制仍有待阐明。
方法： 在本研究中，我们采用D-半乳糖（D-gal）诱导的小鼠模型和D-gal处理的HEI-OC1细胞来模拟ARHL过程。进行听性脑干反应（ABR）检测以评估小鼠听力功能。采用免疫组织化学和免疫荧光评估DUSP1表达水平。分别通过衰老相关β-半乳糖苷酶（SA-β-gal）活性和TUNEL assay定量细胞衰老和凋亡。通过测量线粒体膜电位和ATP水平评估线粒体功能。使用透射电子显微镜（TEM）以及LCB与MitoTracker的免疫荧光共定位评估线粒体自噬相关变化。
结果： D-gal给药导致听力功能显著恶化，伴随SA-β-gal活性增加、耳蜗基底膜底转毛细胞数量减少以及DUSP1表达降低。DUSP1过表达减轻了D-gal诱导的HEI-OC1细胞衰老和凋亡，导致线粒体膜电位和ATP水平增强，并增加线粒体自噬相关变化。相反，敲低BNIP3L/NIX通过抑制线粒体自噬相关变化并促进细胞衰老和凋亡，部分逆转了DUSP1的保护作用。
讨论： 我们的发现强调了DUSP1驱动的线粒体自噬相关变化在对抗D-gal触发的耳蜗毛细胞损伤中的关键作用。调节DUSP1-BNIP3L/NIX轴可能为ARHL干预提供新的治疗见解。
结论： 体外实验结果表明，DUSP1通过正向调控线粒体自噬相关变化减轻D-gal诱导的耳蜗毛细胞损伤。BNIP3L/NIX部分介导了DUSP1在HEI-OC1细胞中的保护作用。

英文摘要

INTRODUCTION: Dual-Specificity Phosphatase 1 (DUSP1) has been proven to be closely correlated with Age-Related Hearing Loss (ARHL) and mitophagy progression. However, the function of DUSP1 in cochlear hair cell injury and the underlying mechanism remain to be elucidated.
METHODS: In this study, we employed D-galactose (D-gal)- induced mouse models and D-gal-treated HEI-OC1 cells to simulate the ARHL process. Auditory brainstem response (ABR) detection was performed to evaluate mouse hearing function. Immunohistochemistry and immunofluorescence were utilized to assess DUSP1 expression levels. Cell senescence and apoptosis were quantified through senescence-associated β-galactosidase (SA-β-gal) activity and TUNEL assay, respectively. Mitochondrial function was assessed by measuring mitochondrial membrane potential and ATP levels. Mitophagy-associated changes were evaluated using Transmission Electron Microscopy (TEM) and immunofluorescence colocalization of LCB and MitoTracker.
RESULTS: D-gal administration resulted in a significant deterioration in hearing function, accompanied by increased SA-β-gal activity, reduced the number of hair cells in basal turns of the cochlear basilar membranes, and decreased DUSP1 expression. Overexpression of DUSP1 mitigated D-gal-induced senescence and apoptosis in HEIOC1 cells, leading to enhanced mitochondrial membrane potential and ATP levels, and increased mitophagy-associated changes. Conversely, knockdown of BNIP3L/NIX partially reversed the protective effects of DUSP1 by inhibiting mitophagy-associated changes and promoting cellular senescence and apoptosis.
DISCUSSION: Our findings highlighted the critical role of DUSP1‑driven mitophagyassociated changes against D‑gal‑triggered cochlear hair cell damage. Modulation of the DUSP1‑BNIP3L/NIX axis might offer new therapeutic insights for ARHL intervention.
CONCLUSION: The in vitro experimental results demonstrated that DUSP1 alleviated Dgal- induced cochlear hair cell injury via positively regulating mitophagy-associated changes. BNIP3L/NIX partially mediated the protective effects of DUSP1 in HEI-OC1 cells.