Various studies have indicated that MSCs derived from diverse sources can differentiate into dopaminergic neurons when subjected to specific combinations of growth factors and chemical agents (e.g., bFGF, BDNF, GDNF, IGF-1, retinoic acid, forskolin, ultrasound hedgehog, etc.).384,385 Offen et al.386 reported that transplanted BM-MSCs differentiated into dopaminergic-like cells and successfully improved the behavior of PD model mice. Here, BDNF is linked to Parkinson disease.