Baicalein improves Na₂SeO₃ induced cataract by enhancing the antioxidant capacity of juvenile Sprague Dawley Rat

Ethnopharmacological relevance: Baicalein (BAI) is the crucial flavonoid component in Scutellaria baicalensis Georgi, possessing biological functions such as anti-oxidant, anti-apoptotic, and anti-inflammatory. However, there is limited intensive pharmacological and mechanistic research on the therapeutic effects of BAI for cataract treatment.

Aim of the study: This study aimed to investigate the effects and mechanisms of BAI on Na₂SeO₃-induced cataract in juvenile rats.

Materials and methods: The cataract model was established by a single subcutaneous injection of 3.46 mg/kg Na₂SeO₃ on the back of 10-day-old rats. The BAI (25 mg/kg, 50 mg/kg, 100 mg/kg) was administered to the 8-day-old rats and continued until they reached 30 days of age, and the opacity of the lens was observed using a slit lamp microscope every 3 days. Pathological changes in the lens were observed using hematoxylin-eosin (HE) staining to investigate the effects of BAI on Na₂SeO₃-induced cataract in rats. The levels of antioxidant substances in rat serum and the lens, as well as the levels of soluble and insoluble proteins in rat lens, were measured by the reagent kit. Furthermore, the mechanism of BAI on Na₂SeO₃-induced cataract rats was analyzed by network pharmacology, molecular docking, and Western blot.

Results: BAI significantly increased the content of soluble proteins in the lens, mitigated the dense opacity of rat lens and reduced the damage to lens epithelial cells, reduced the levels of malondialdehyde (MDA) in rat serum and lens, increased the levels of total superoxide dismutase (T-SOD) and Glutathione peroxidase (GSH-PX). The improvement effects of BAI on Na₂SeO₃-induced cataract may related to the mitogen-activated protein kinase (MAPK) and the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathways.

Conclusion: In conclusion, this study demonstrated that BAI could mitigate the dense opacity of rat lens in Na₂SeO₃-induced cataract rats, which may be achieved through the MAPK signaling pathway and the PI3K/AKT signaling pathway.