Metabolomic and microbiome profiling reveals the anti-Pb effect of Lactiplantibacillus plantarum

As a toxic environmental contaminant, lead (Pb) enters the body via the food chain and leads to a disturbance of the gut microbiota. Lactiplantibacillus plantarum CCFM8661 was found to be favorable in decreasing Pb concentrations in the blood and organs of chronically Pb-ingested mice and in promoting fecal Pb excretion. The alterations of the colonic microbiome as well as the colonic and serum metabolomes of chronically Pb-exposed mice after L. plantarum CCFM8661 intervention were investigated. It was observed that L. plantarum CCFM8661 induced significant changes in α and β diversity, increasing Bacteroides, Bifidobacterium, and Dubosiella, which are regarded as beneficial genera, and decreasing harmful genera such as Bilophila. Untargeted metabolomics identified that L. plantarum CCFM8661 significantly increased serum level of lauric acid as well as colonic levels of taurine and metabolites in the purine metabolism pathway, including xanthine, deoxyinosine, hypoxanthine, guanine, and deoxyguanosine. These metabolites were associated with differential bacteria and contributed to repairing the intestinal barrier and facilitating Pb excretion. It turned out that regulation of gut microbiota and its metabolic activity may be one of the important reasons why L. plantarum CCFM8661 alleviates the symptoms of Pb poisoning.