TRIM3 Inhibits H₂O₂-Induced Apoptosis in Human Lens Epithelial Cells by Decreasing p53 via Ubiquitination

Purpose: Cataract is a leading visual disease characterized by enhanced oxidative stress and increased apoptosis of human lens epithelial cells (HLECs). TRIM3 is a tumor suppressor in many cancers. However, its role in cataract remains unknown. In this study, we aimed to explore the role of TRIM3 in H₂O₂-injured HLECs and the underlying mechanisms involved.

Methods: HLECs were treated with different H₂O₂ concentrations to induce apoptosis. A lentivirus was designed to overexpress TRIM3 and p53, and TRIM3 knockdown was prepared. A P53 inhibitor, PFTα, was used to knockdown p53. Cell viability and apoptosis were detected by CCK-8 and flow cytometric analyses, respectively. TRIM3, p53, Bcl2, and Bax expression levels were determined by qRT-qPCR and western blotting.

Results: It was found that H₂O₂-treated HLECs had markedly decreased cell viability and TRIM3 expression. TRIM3 overexpression attenuated the H₂O₂-induced HLEC apoptosis, while TRIM3 knockdown promoted it. P53, a downstream target of TRIM3, was found to be negatively regulated by TRIM3 via ubiquitination in HLECs. Furthermore, p53 overexpression abolished the effect of TRIM3 overexpression on H₂O₂-induced HLEC apoptosis, while PFTα alleviated the TRIM3 knockdown-mediated HLEC apoptosis.

Conclusion: This study demonstrates that TRIM3 inhibited the H₂O₂-induced apoptosis of HLECs by decreasing p53 via ubiquitination.