Protective Effects of Piceatannol on Hydrogen Peroxide-induced Damage to Human Corneal Epithelial Cells

OBJECTIVE  To investigate the protective effect and mechanism of piceatannol on hydrogen peroxide(H₂O₂)-induced injury of human corneal epithelial cells(HCECs).

METHODS  HCECs were cultured in vitro, the effects of different concentrations of H₂O₂ and piceatannol on HCECs activity were detected by CCK-8 method. The working concentration of H₂O₂ was screened out. The lactate dehydrogenase(LDH) release levels in HCECs after intervention with different concentrations of piceatannol were measured using an LDH assay kit, and the optimal concentration of piceatannol was determined. The cells were divided into four groups: the control group, the model group, the 40 μmol·L^–1 piceatannol group, and the 80 μmol·L^–1 piceatannol group. Reactive oxygen species(ROS) generation was detected using the 2′,7′-dichlorodihydrofluorescein diacetate(DCFH-DA) probe. Cell migration ability was evaluated using the scratch assay. Changes in the expression levels of Bcl-2, Bax, and cleaved caspase-3 proteins in HCECs were examined by Western blotting. The SIRT1 agonist SRT1720 and inhibitor EX527 were used to validate the relationship between piceatannol and the SIRT1/FOXO3a/BNIP3 signaling pathway.

RESULTS  The results of cell proliferation assay and cytotoxicity assay showed that, compared with the control group, H₂O₂-treated HCECs exhibited reduced cell viability, increased LDH release, elevated ROS levels, and impaired scratch wound healing ability. Western blotting analysis showed that, H₂O₂ treatment downregulated the expression of Bcl-2 while upregulating the expression of Bax and cleaved caspase-3 in HCECs. In contrast, compared with the model group, piceatannol treatment enhanced the viability of HCECs, decreased LDH release, reduced intracellular ROS levels, and promoted scratch wound healing. By using the SIRT1 agonist SRT1720 and inhibitor EX527, it was found that both EX527 and H₂O₂ could inhibit the expression of SIRT1, FOXO3a and BNIP3 in HCECs, and this effect was reversed by piceatannol, which was synergistically SRT1720 further increased the expression levels of SIRT1, FOXO3a and BNIP3.

CONCLUSION  Piceatannol may ameliorate H₂O₂-induced HCECs injury by activating the SIRT1/FOXO3a/BNIP3 signaling pathway.