Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin, China, Tianjin Branch of National Clinical Research Center for Ocular Disease, Tianjin, China, Eye Institute and School of Optometry, Tianjin, China, Tianjin Medical University Eye Hospita, Tianjin, China.
Tianjin Eye Hospital, Tianjin Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin, China.
Bioengineered. 2022 May;13(5):12955-12971. doi: 10.1080/21655979.2022.2079270.
Etiology and pathogenesis of age-related cataract is not entirely clear till now. Senescence marker protein 30 (SMP30) is a newly discovered anti-aging factor, which plays an important role in preventing apoptosis and reducing oxidative stress damage. Mitochondria are located at the intersection of key cellular pathways, such as energy substrate metabolism, reactive oxygen species (ROS) production and apoptosis. Oxidative stress induced by 4-hydroxynonenal (4-HNE) is closely related to neurodegenerative diseases and aging. Our study focused on the effect of SMP30 on mitochondrial homeostasis of human lens epithelial cells (HLECs) induced by 4-HNE. Western blots and qPCR were used to compare the expression of SMP30 protein in the residual lens epithelial cells in the lens capsule of age-related cataract (ARC) patients and the donated transparent lens capsule. On this basis, SMP30 overexpression plasmid and SMP30 shRNA interference plasmid were introduced to explore the effect of SMP30 on the biological behavior in HLECs under the condition of oxidative stress induced by 4-HNE through immunohistochemistry, ROS evaluation, metabolic spectrum analysis and JC-1 fluorescence measurement. Given that Nuclear Factor erythroid 2-Related Factor 2 (Nrf2)/Kelch Like ECH Associated Protein 1 (KEAP1) signaling pathway is the most important antioxidant stress pathway, we further analyzed the regulatory effect of SMP30 by WB to explore its molecular mechanism. Our study indicated that SMP30 may inhibit ROS accumulation, restore mitochondrial function, activate Nrf2/Keap1 signaling pathway, therefore protecting lens epithelial cells from oxidative stress-induced cell damage.
年龄相关性白内障的病因和发病机制尚不完全清楚。衰老标志物蛋白 30（SMP30）是一种新发现的抗衰老因子，在预防细胞凋亡和减少氧化应激损伤方面发挥着重要作用。线粒体位于细胞内关键途径的交汇处，如能量底物代谢、活性氧（ROS）产生和细胞凋亡。4-羟壬烯醛（4-HNE）诱导的氧化应激与神经退行性疾病和衰老密切相关。我们的研究集中在 SMP30 对 4-HNE 诱导的人晶状体上皮细胞（HLECs）线粒体稳态的影响。Western blot 和 qPCR 用于比较年龄相关性白内障（ARC）患者晶状体囊内残留晶状体上皮细胞和捐赠透明晶状体囊内 SMP30 蛋白的表达。在此基础上，通过免疫组化、ROS 评价、代谢谱分析和 JC-1 荧光测量，引入 SMP30 过表达质粒和 SMP30 shRNA 干扰质粒，探讨 SMP30 在 4-HNE 诱导的氧化应激条件下对 HLECs 生物学行为的影响。鉴于核因子红细胞 2 相关因子 2（Nrf2）/Kelch 样 ECH 相关蛋白 1（KEAP1）信号通路是最重要的抗氧化应激通路，我们进一步通过 WB 分析 SMP30 的调节作用，以探讨其分子机制。我们的研究表明，SMP30 可能通过抑制 ROS 积累、恢复线粒体功能、激活 Nrf2/Keap1 信号通路，从而保护晶状体上皮细胞免受氧化应激诱导的细胞损伤。
