Protocatechuic acid inhibits neurotoxicity induced by MPTP in vivo

Parkinson's disease (PD) is characterized by the progressive degeneration of dopaminergic neurons in substantia nigra (SN) with the presence of alpha-synuclein inclusions termed Lewy bodies. The neuroprotective effects of protocatechuic acid (PAc) both in vitro and in vivo have been reported. However, little is known about the effects of PAc on neurotoxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in vivo. In this study, we demonstrated that PAc inhibited the reduction of the latent periods in a rotarod test, and the contents of dopamine (DA) and its metabolites in striatum, and furthermore, it ameliorated the pathology in SN and the decreases in the expression of tyrosine hydroxylase (TH) in SN of C57BL/6J mice induced by MPTP. Taken together, our results indicate for the first time that PAc has neuroprotective effects on MPTP treated C57BL/6J mice and may be useful in clinical treatment of PD.