Neuroprotective effects of pramipexole transdermal patch in the MPTP-induced mouse model of Parkinson's disease

Parkinson's disease (PD) is characterized by the selective death of dopaminergic neurons. To avoid inconvenience of frequent administration caused by short half life and recurrence of symptoms such as tremor and bradykinesia incurred by drug elimination, a novel long-acting pramipexole transdermal patch has been made. In the present study, we evaluated the neuroprotective effects and underlying mechanisms of pramipexole patch (PPX patch) in a subacute PD mouse model induced by 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The results showed that PPX patch treatment improved dyskinesia. MPTP-induced reduction of DA as well as its metabolites DOPAC and HVA in the striatum were prevented by PPX patch in a dose-dependent manner. PPX patch also restored the activity of antioxidant enzymes including SOD, GSH-Px and CAT in the striatum while reduced the content of MDA. Furthermore, PPX patch upregulated Nrf2/HO-1 expression. The protective effects of PPX patch was also associated with downregulation of the Bax/Bcl-2 ratio and Apaf-1, inhibition of cytochrome c release and inactivation of caspase-9 and caspase-3. In conclusion, our studies demonstrated that the long-acting pramipexole patch exerts its neuroprotective effects, at least in part, by inhibiting oxidative stress and mitochondrial apoptosis pathway and holds promise as a candidate drug.