FNDC5 and Parkinson disease: In an MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine), animal model of PD, authors showed that rats treated with irisin and bone marrow stromal cells (BMSCs) prevented the dopaminergic neurons loss and irisin facilitated the stem cells with regenerative ability inducing the migration of BMSCs in the damaged brain area (Ref.