More importantly, the expression of α-synuclein, a specific biomarker of PD, was reduced, and the genes and proteins related to the mitochondrial apoptotic pathway were changed in the presence of tFNAs.175 To enhance the therapeutic efficacy of tFNAs on PD, vitamin B12 (VB12), inhibiting the activity of leucine-rich repeat kinase 2 (LRRK2), a major neurotoxicity factor, was loaded onto tFNAs, named TVC. This evidence concerns the gene LRRK2 and Parkinson disease.