Quercetin upregulates steroid hormone biosynthesis to enhance reproductive performance in roosters.

Quercetin (Que) possesses diverse biological activities and has been extensively investigated in various fields, but its impact on rooster reproductive performance and the underlying mechanisms remains poorly understood. The present study investigated the effect of quercetin on reproductive performance of roosters and preliminarily explored its underlying regulatory mechanism. Forty-eight 100-day-old roosters were randomly divided into control group and three quercetin groups (Que_5mg/d, Que_10mg/d, and Que_20mg/d). Daily gavage was conducted continuously for 60 days. Semen quality was evaluated using a sperm analyzer. Then, metabolomics, proteomics, network pharmacology, molecular dynamics simulation, hormone detection, qRT-PCR, and their combination analysis was employed for mechanism validation. The result of semen quality evaluation and testicular tissue morphology observation showed that quercetin can significantly increase the semen collection volume, semen motility (P < 0.05), sperm density was significantly higher in the Que_5mg/d and Que_10mg/d groups than in the control group (P < 0.05), and the diameter of the seminiferous tubules, the height of the seminiferous epithelium of the testes (P < 0.05). Consistently, both testicular metabolomics and hormone detection results indicated that quercetin significantly increased testosterone levels (P < 0.05). Metabolite KEGG enrichment analysis revealed a significant upregulation of the steroid hormone biosynthesis. Proteomics and qRT-PCR assays confirmed that quercetin upregulated the expression of genes such as CYP11A1, CYP17A1, and molecular docking and molecular dynamics simulations further indicate that quercetin has a favorable binding with steroid hormone biosynthesis related protein CYP11A1. These results demonstrates that supplementation with quercetin at a dosage of 10 mg/d can enhances reproductive performance in roosters by targeting steroid hormone biosynthesis-related proteins to promote hormone synthesis.