Scinderin Promotes Hydrogen Peroxide-induced Lens Epithelial Cell Injury in Age-related Cataract

Scinderin (SCIN) is a calcium-dependent protein implicated in cell growth and apoptosis by regulating actin cleavage and capping. In this study, we investigated the role of SCIN in hydrogen peroxide-induced lens epithelial cell (LEC) injury related to age-related cataract (ARC).

Anterior lens capsules from ARC patients were collected to examine SCIN expression levels. Immortalized human LEC cell line SRA01/04 and lens capsules freshly isolated from mice were induced by H₂O₂ to mimic the oxidative stress in ARC. The role of SCIN was investigated by gain-of-function (overexpression) and loss-offunction (knockdown) experiments. Flow cytometry (FCM) and Western-blot (WB) assays were performed to investigate the effect of SCIN on apoptosis. The oxidative stress (OS) was examined by detecting malondialdehyde (MDA) level, superoxide dismutase (SOD) and catalase (CAT) activity. The interaction between SCIN mRNA and miR-489-3p was predicted by StarBase and miRDB databases and validated by luciferase reporter activity assay.

SCIN was significantly elevated in cataract samples, and the expression levels were positively correlated with the nuclear sclerosis grades. SCIN overexpression promoted OS and apoptosis in H₂O₂-induced SRA01/04 cells, while SCIN silencing showed the opposite effect. We further showed that miR-489-3p was a negative regulator of SCIN. miR-489-3p overexpression suppressed apoptosis and OS in H₂O₂-induced SRA01/04 cells by targeting SCIN.

Our study identified SCIN as an upregulated gene in ARC, which is negatively regulated by miR-489-3p. Targeting miR-489-3p/SCIN axis could attenuate OS-induced apoptosis in LECs.