Lactobacillus exerts anti-depression effects by regulating gut microbiota and metabolites in Ampicillin administered C57BL/6J mice

The probiotic modifying gut microbiota to reduce neuroinflammation and anti-depression by the gut-brain axis path is a potential issue. This study investigates the anti-depression potential of C57BL/6 mice feeding Lactobacillus spp. (LAB) under Ampicillin (Amp) induction. After 10 Lactobacillus spp were assessed by recovery rate test from the depression behavior, there are three higher potential Lactobacillus spp. were combined as low and high dosage material groups, including a low dosage Lactobacillus spp. (1.6 x 108 CFU/mice, LABL) and high dosage Lactobacillus spp. (4.8 x 108 CFU/mice, LABH). The gut microbiota composition, nutrient metabolism paths, short-chain fatty acid levels, and inflammatory factors were analyzed after C57BL/6J mice were fed LAB under Amp induction. Results showed that under C57BL/6J mice induced by Amp, both two LAB groups could recover from the depression behavior effect. LAB treatment also could lead to mice ileum’s Firmicutes abundance decreasing, and the Actinobacteria and Bacteroidetes were increased. The microbes functional pathway prediction found that two LAB groups increased arginine and proline metabolism, cyanoamino acid metabolism, and nicotinate and nicotinamide metabolism and decreased fatty acid synthesis. LABH groups increased the levels of acetic acid, propanoic acid and iso-butyric acid and decreased butyric acid levels in the cecum. And LABH treatment also can improve claudin5 mRNA and reduce the IL-6 mRNA expression. These results showed treatment exerts the composite LAB of L. rhamnosus GMNL-74, L. acidophilus GMNL-185 and L. plantarum GMNL-141 anti-depression effects by regulating gut microbiota and modifying depression-related metabolites in C57BL/6J Amp administered Mice.