The physiological damage caused by 17β-estradiol in Chinese longsnout catfish (Leiocassis longirostris)

Hormone-induced sex reversal is a widely employed technique for the large-scale production of mono-sex or mono-gender populations in aquaculture. However, the improper and irrational use of exogenous hormones can negatively impact the physiological functions of aquatic animals. To investigate the potentially toxic effects of hormones on the Chinese longsnout catfish ( Leiocassis longirostris ), which exhibits marked sexual dimorphism in growth, we conducted an experiment in which L. longirostris was maintained in tanks and fed a diet containing varying concentrations of 17β-estradiol (E2) from 30 to 60 days post-hatching (dph). The experimental feed included E2 concentrations of 50 mg E2/kg, 100 mg E2/kg, and 150 mg E2/kg. The results showed that E2 administration suppressed body weight and survival rate, and induced hepatic and renal damage whose severity was positively correlated with E2 concentration. Transcriptomic and metabolomic analyses revealed that feeding with E2-contaminated feed for 30 days impaired metabolic functions in liver tissues, disrupting energy metabolism, amino acid metabolism, and lipid metabolism. This impairment resulted in a decrease in most amino acid-related metabolites and an increase in various lipid metabolites. Additionally, several metabolic regulatory factors, including Psma3, Psma4, and PGD were identified. Furthermore, excessive E2 intake was found to disrupt liver phase I metabolic pathways, particularly those associated with xenobiotic and drug metabolism via cytochrome P450. In summary, this study systematically evaluates the physiological damage caused by E2 in the Chinese longsnout catfish and provides important insights for future mono-sex breeding strategies in L. longirostris .