TRPV1 and Parkinson disease: Many experimental studies demonstrated that TRPV1 activation by capsaicin (CAP) prevents the degeneration of nigrostriatal dopamine neurons in the 1-methyl-4-phenylpyridinium- (MPP+-) or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine- (MPTP-) or 6-hydroxy dopamine (6-OHDA-) lesioned rodent model of PD via inhibiting glial-derived inflammatory responses and producing ciliary neurotrophic factor (CNTF) [11–13].