Abstract: Objective: To explore the preventive effect of Lactobacillus paracasei FZU103 (LP-FZU103) on alcoholic liver injury (ALI). Methods: Altogether 36 specific pathogen free- (SPF-) grade ICR mice were randomly divided into three groups: control, model and experimental (LP-FZU103 intervention). After the six-week experiment, body mass, organ coefficients, serum and liver biochemical indexes, liver histopathology and inflammatory cytokines, the transcription of liver function-related genes and intestinal flora composition were measured. Results: Compared with the model group, intervention of LP-FZU103 improved the organ coefficients and pathological liver damage in ALI mice, significantly reduced the levels of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) as well as the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the serum, increased the serum concentration of high-density lipoprotein cholesterol (HDL-C), significantly increased the activity of catalase (CAT) and superoxide dismutase (SOD) and the content of glutathione (GSH) in the liver, and decreased MDA content and interleukin-6 (IL-6), interferon-γ (IFN-γ) levels in the liver. Moreover, LP-FZU103 intervention significantly up-regulated the mRNA expression level of the lipid metabolism-related gene Ldlr and down-regulated the mRNA expression level of Acc1, Hmgcr and Cd36 as well as increased the relative abundance of beneficial bacteria such as Lactobacillus johnsonii, Lactobacillus reuteri and Lactobacillus paracasei in the gut of mice. Conclusion: LP-FZU103 intervention can prevent and control the occurrence of alcoholic liver injury in mice, which is closely related to the improved intestinal flora and liver metabolic function.

Key words: Lactobacillus paracasei; alcoholic liver injury; oxidative stress; liver function-related genes; intestinal flora