High intake of B complex attenuates 6-hydroxydopamine-induced arkinsonism in rat

Several lines of evidence show that high plasma level of homocysteine (Hcy) induces development or exacerbates Parkinson’s disease. B vitamins are necessary for Hcy metabolism and control plasma level of Hcy. In the present study، we studied the effect of B vitamin supplementation on the 6-hydroxydopamine (6-OHDA) -induced Parkinsonism in rat. Rats were nourished with B vitamin supplements from 1 month before the surgery till the end of experiment. 6-OHDA was injected into the striatum of rat brains by stereotaxic surgery. Development and severity of the Parkinsonism were assessed by three conventional behavioral tests. Serum level of Hcy was measured before the surgery and at the end of experiment. Supplement of B complex significantly attenuated behavioral symptoms of the Parkinsonism. Supplement of B6 improved rotational behavior of the rats but had no effect on the swing and rotarod tests. Supplements of B12 and combination of B6، B12 and folate had no remarkable effect. Supplements of B6، B12 and B complex decreased serum level of Hcy before the surgery. In the end of the experiment، however، there was no significant difference for serum level of Hcy between experimental groups. Our results indicate that high intake of B complex can provide anti-Parkinsonism effect which is not mediated by lowering plasma Hcy.