Li Yuchen, Xu Weida, Zhao Guiyang, Guo Yuchen, Wang Liyuan, Du Qianming, Fei Yuxiang, Hu Xueteng, Hu Haoshen, Chen Lixun, Xu Yidan
Department of Ophthalmology, Nanjing First Hospital, Nanjing Medical University, Nanjing, People's Republic of China.
General Clinical Research Center, Nanjing First Hospital, Nanjing Medical University, Nanjing, People's Republic of China.
Clin Ophthalmol. 2025 Jul 16;19:2343-2362. doi: 10.2147/OPTH.S521660. eCollection 2025.
Recent studies have demonstrated that mitochondrial dysfunction is pivotal in early diabetic retinopathy (DR). Tumor necrosis factor-associated protein 1 (TRAP1), a mitochondrial chaperone regulating stress responses, remains unexplored in DR pathogenesis.
We established in vivo and in vitro models of DR. Hematoxylin and eosin (H&E) staining was utilized to evaluate retinal lesions in rats. Western blotting, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and immunofluorescence staining were employed to assess TRAP1 expression in the retina. Cell viability, reactive oxygen species (ROS), mitochondrial damage, and TRAP1 expression levels were measured in ARPE-19 cells. RNA sequencing (RNA-seq) identified gene expression and pathway changes in shTRAP1 cells. The role of TRAP1 in ferroptosis in ARPE-19 cells was evaluated with or without ferrostatin-1 (Fer-1) and erastin. Potential ferroptosis-related proteins interacting with TRAP1 were validated using co-immunoprecipitation (CO-IP) techniques. This study confirmed TRAP1's critical role in the pathogenesis of DR.
Our findings elucidate a significant reduction in TRAP1 expression in diabetic rat retinas, particularly in the pigment epithelium. High glucose levels correspondingly diminished TRAP1 expression in ARPE-19 cells, causing decreased cellular viability, increased ROS generation, and mitochondrial dysfunction. Notably, the overexpression of TRAP1 effectively preserved mitochondrial homeostasis under stress, mitigated mitochondrial impairment, and enhanced cellular viability. Importantly, TRAP1 may alleviate hyperglycemia-induced mitochondrial damage by reducing ferroptosis through its interactions with ferroptosis-related proteins, including acyl-CoA synthetase long-chain family member 1 (ACSL1), acyl-CoA synthetase long-chain family member 4 (ACSL4), and cytochrome b5 reductase 1 (CYB5R1).
TRAP1 exerts a protective influence on mitochondrial function in ARPE-19 cells. Reduced levels of TRAP1 may play a crucial role as an early contributor to mitochondrial dysfunction in diabetic retinopathy. Furthermore, the association of TRAP1 with ferroptosis improves cellular viability by enhancing mitochondrial resilience against high glucose-induced stressors and preventing cellular ferroptosis.
近期研究表明，线粒体功能障碍在早期糖尿病视网膜病变（DR）中起关键作用。肿瘤坏死因子相关蛋白1（TRAP1）是一种调节应激反应的线粒体伴侣蛋白，其在DR发病机制中的作用尚不清楚。
我们建立了DR的体内和体外模型。采用苏木精-伊红（H&E）染色评估大鼠视网膜病变。运用蛋白质免疫印迹法、逆转录定量聚合酶链反应（RT-qPCR）和免疫荧光染色评估视网膜中TRAP1的表达。在ARPE-19细胞中检测细胞活力、活性氧（ROS）、线粒体损伤及TRAP1表达水平。通过RNA测序（RNA-seq）确定shTRAP1细胞中的基因表达和通路变化。使用或不使用铁死亡抑制剂1（Fer-1）和埃拉斯汀评估TRAP1在ARPE-19细胞铁死亡中的作用。运用免疫共沉淀（CO-IP）技术验证与TRAP1相互作用的潜在铁死亡相关蛋白。本研究证实了TRAP1在DR发病机制中的关键作用。
我们的研究结果表明，糖尿病大鼠视网膜中TRAP1表达显著降低，尤其是在色素上皮细胞中。高糖水平相应降低了ARPE-19细胞中TRAP1的表达，导致细胞活力下降、ROS生成增加和线粒体功能障碍。值得注意的是，TRAP1的过表达在应激状态下有效维持了线粒体稳态，减轻了线粒体损伤，并提高了细胞活力。重要的是，TRAP1可能通过与铁死亡相关蛋白相互作用，包括酰基辅酶A合成酶长链家族成员1（ACSL1）、酰基辅酶A合成酶长链家族成员4（ACSL4）和细胞色素b5还原酶1（CYB5R1），减少铁死亡，从而减轻高血糖诱导的线粒体损伤。
TRAP1对ARPE-19细胞的线粒体功能具有保护作用。TRAP1水平降低可能是糖尿病视网膜病变中线粒体功能障碍的早期重要因素。此外，TRAP1与铁死亡的关联通过增强线粒体对高糖诱导应激源的耐受性和防止细胞铁死亡来提高细胞活力。
