Lactobacillus protects against lead-induced hepatotoxicity by preserving the gut barrier and microbiota remodeling

Lead (Pb) toxicity is a global health concern that primarily affects the liver. This study explored the protective effects of lactobacilli against Pb(II)-induced hepatotoxicity in mice. Three strains of lactobacilli— Lacticaseibacillus paracasei GMNL-32, Limosilactobacillus fermentum GMNL-93, and Lacticaseibacillus casei GMNL-277—were evaluated for Pb adsorption and cytoprotective properties. The results indicated that probiotic treatment reduced the liver-to-body weight ratio, aspartate transaminase and alanine transaminase levels, and liver damage without increasing Pb excretion. It also upregulated the expression of gut tight junction proteins, reduced the levels of inflammatory cytokines (tumor necrosis factor-α and interleukin-6), and modulated the diversity and composition of the gut microbiota. Strong correlations were observed between probiotics, microbial abundance, metabolic pathways, and reduced liver inflammation. Overall, this study suggests that GMNL-32, GMNL-93, and GMNL-277 can mitigate Pb-induced hepatotoxicity by modulating the gut microbiota and regulating metabolism. Thus, these probiotics hold promise as protective agents against Pb-induced hepatotoxicity.