A probiotic formulation protects the dopaminergic neurons via attenuating the intestinal inflammation in mice of Parkinson’s disease

Abstract Objective Targeting the intestinal inflammation becomes a strategy for Parkinson’s disease (PD) treatment. This study investigated the neuroprotective effects of a probiotic formulation, VSL#3® formulation, and the involvement of the anti-inflammation, in particular the intestinal inflammation. Materials and Methods The probiotics was orally administrated to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD for six weeks. Results The striatal content of dopamine and its metabolites, the survival of dopaminergic neurons in the substantia nigra were substantially increased in probiotics treatment mice compared to PD mice. The pro-inflammatory cytokines in the striatum were significantly suppressed while the anti-inflammation mediators were dramatically up-regulated by probiotics. The probiotics attenuated the intestinal inflammation via regulating the gut microbial composition. The mRNA expression of Tumor Necrosis Factor- α ( TNF-α) and Interleukin-1β ( IL-1β) mRNA significantly decreased in probiotic treatment mice compared to PD mice. Besides, the circulating levels of pro-inflammatory cytokines were notably decreased, indicating the blocked transfer of inflammatory cytokine from gut via blood. Conclusion Probiotics protect dopaminergic neurons in PD mice by attenuating the neuroinflammation via inhibiting the intestinal inflammation, which is acquired by restoring the imbalanced gut microbial composition, providing evidence for the idea of targeting the intestinal inflammation as well as using probiotics for PD treatment.