Investigation of Fructus Ligustri Lucidi for Premature Ovarian Insufficiency based on a Network Pharmacology and Experiment Verifications.

Introduction: Premature ovarian insufficiency [POI] is a disease characterized by a premature decline in ovarian function before the age of 40. In China, Ligustrum lucidum [FLL] has long been used to improve ovarian function and treat POI.

Methods: This study aims to verify the effect of FLL on POI through network pharmacology, molecular docking, and in-vitro cell experiments.

Results: A total of 13 active substances were screened in FLL, including including quercetin, taxifolin, luteolin, kaempferol, and beta-sitosterol. Then, network analysis found that FLL may exert effects on POI through 10 targets, including AR, ESR1, ESR2, KDR, CYP19A1, CLPP, GC, MMP3, PPARG, and STS. According to GO and KEGG enrichment analysis, FLL is associated with mechanisms related to estrogen, including steroid hormone biosynthesis, ovarian steroidogenesis, and the estrogen signaling pathway. Molecular docking confirms the interaction between the active ingredients of FLL and CYP19A1, which encodes aromatase. CCK8 experiment confirmed that quercetin and taxifolin can enhance the proliferation of KGN granulosa cells, while quercetin, taxifolin, and kaempferol can inhibit the apoptosis of KGN granulosa cells. ELISA experiments have confirmed that quercetin, taxifolin, luteolin, and kaempferol can increase the synthesis of estradiol in KGN granulosa cells. WB confirms that quercetin can increase the expression level of CYP19A1 in KGN cells.

Conclusion: FLL can improve the proliferation, apoptosis, and synthesis of estradiol in ovarian granulosa cells, and has the potential to treat POI.