In the field of neurodegenerative diseases, research on Parkinson’s disease (PD) has demonstrated that L. salivarius LS01 and L. acidophilus significantly reduce levels of TNF-α, IL-6, and IL-17A, while enhancing the expression of IL-4 and IL-10 through the stimulation of peripheral blood mononuclear cells (PBMCs) in PD patients [156]. This evidence concerns the gene IL4 and Parkinson disease.