Tripchlorolide-induced reversible impairment of male fertility and the involvement of PI3K/Akt/mTOR signaling

Tripchlorolide, a low-toxicity derivative of the natural product triptolide, exhibits significant therapeutic potential for inflammatory and autoimmune diseases; however, its profile of male reproductive toxicity remains a major concern for clinical translation. To address this, we first established its median lethal dose at 33.13 mg/kg in mice to guide safe exposure levels. We then systematically evaluated its reproductive toxicity in male rats following 8-week intraperitoneal administration (2.5, 5, and 10 μg/kg/day). Our results demonstrated a clear dose-dependent toxicity, characterized by significant reductions in testicular and epididymal coefficients, impaired sperm count and motility, disrupted testosterone, follicle-stimulating hormone, and luteinizing hormone levels, and evident histopathological damage in the testes and epididymides. Encouragingly, these adverse effects showed signs of reversal after a 4-week recovery period, suggesting that the impairment is reversible. Through an integrated approach combining network pharmacology prediction and molecular docking, we identified the inhibition of the PI3K/Akt/mTOR signaling pathway as the pivotal molecular event. This mechanism was conclusively validated by our in vivo rescue experiment, where co-administration of the Akt activator SC79 markedly attenuated the tripchlorolide-induced reproductive impairments. Our study provides a comprehensive toxicological profile, defining the dose-response, reversibility, and mechanistic basis of tripchlorolide's male reproductive toxicity, thereby offering critical insights for its risk assessment and potential repurposing.