Protective effects of oxyresveratrol on motor functions in 6-OHDA-Induced neurodegeneration

Abstract

Parkinson disease (PD) is the second most common neurodegenerative disorder, associated with progressive loss of dopaminergic neurons in the substantia nigra. Majority of PD is due to environment factors. PD affects approximately 1% of the population over age 55 and 2% of the population over age 65 worldwide and this number is increasing (Dauer et al, 2003). One of the most typical symptoms of PD is motor deficit. Parkinsonian mimetic 6-hydroxydopamine (6-OHDA) can be served as toxin agent in experimental model for PD. Oxyresveratrol (OXY) is a stilbene extracted from mulberry. OXY has been shown to exert antioxidative effects against cerebral ischemia. Our previous studies have shown that OXY elicits neuroprotective effects against experimental PD (Chao et al, 2008). In our in vivo study, male Sprague Dawley rats were fed with OXY, resveratrol (RES) as a positive control and pinostilbene (PINO) as a negative control at a dose of 1 mg/kg for 7 days prior to stereotactic injection of 6-OHDA. Rats were fed for 14 days more after surgery. Apomorphine-triggered rotation was used to test the effectiveness of 6-OHDA to induce dopaminergic neuronal loss and rotarod test were used to assess motor function. We found that OXY attenuated motor deficit induced by 6-OHDA 16.7% ± 0.3 (mean ± standard derivation). We further investigated the effect of OXY (25M) in MES 23.5 and SH-SY5Y cell lines in the in vitro model of PD established by 6-OHDA treatments. There was significantly decreased in the release of lactate dehydrogenase (LDH) in both MES 23.5 (P<0.0001) and SH-SY5Y cells (P<0.05) after OXY treatment comparing with 6-OHDA groups. However, the cleaved caspase 3 expressions only decreased in MES 23.5 cells (P<0.05). In conclusion, OXY displayed protective effect on motor function in 6-OHDA induced PD model.