This study aims to investigate the hepatotoxicity of Psoraleae Fructus water extract and the underlying mechanism in rats. Forty-eight rats were randomly assigned into four groups: a blank group and low-(BZGL, 6.25 g·kg~(-1)), medium-(BGZM, 12.5 g·kg~(-1)), and high-dose(BGZH, 25 g·kg~(-1)) Psoraleae Fructus water extract groups. The rats were treated for 28 days, and toxicity and mortality were observed daily. After 28 days, the rats were sacrificed, and the body weight, liver index, and liver-to-brain ratio were calculated. The morphological changes in the liver tissue were observed, and the serum levels of related biochemical indicators were measured. The results showed that compared with the blank group, Psoraleae Fructus water extracts of different doses decreased the body weight, increased the liver index and liver-to-brain ratio, and caused liver hypertrophy and pathological changes. Pathological examination revealed that the rats in Psoraleae Fructus water extract groups had bile duct hyperplasia, inflammatory cell infiltration, and liver cell fibrosis. Compared with the blank group, BGZL elevated the levels of alanine transaminase(ALT), α-glutathione S-transferase(α-GST), and total bile acid(TBA)(P<0.05), and BGZM and BGZH elevated the levels of ALT, TBA, α-GST, γ-glutamyl transferase(γ-GT), purine nucleoside phosphorylase(PNP), ornithine carbamoyltransferase(OCT), and arginase(ArgI)(P<0.05). Compared with the blank group, Psoraleae Fructus water extracts of different doses down-regulated the mRNA and protein levels of bile salt export pump(BSEP) and farnesoid X receptor(FXR) and up-regulated the mRNA and protein levels of tumor necrosis factor-α(TNF-α), nuclear factor kappaB(NF-κB), and cholesterol 7 alpha-hydroxylase(CYP7A1)(P<0.05). The results suggested that Psoraleae Fructus water extract caused toxicity in rats, showing a dose-toxicity relationship. Psoraleae Fructus water extract may cause liver damage, which may be due to its effect on liver bile acid secretion and induction of inflammation.
Keywords: Psoraleae Fructus water extract; cholestasis; inflammation; liver injury.