Introduction of FGF-20 gene into hUC-MSCs and transplantation into a mouse model of PD significantly improved mouse behavior, accompanied by an increase in tyrosine hydroxylase-positive cells and dopaminergic neurons, which may be related to MSC-FGF-20 promoting the degradation of the transcription factor NF-κB in the nigrostriatal dopaminergic system (Jinfeng et al., 2016). Here, TH is linked to Parkinson disease.