Abstract

It has been recognized that Gastrodia elata Bl (GE), an oriental herb medicine, ameliorates various neurological disorders, that GE modulates the monoaminergic and GABAergic systems, and that GE possess antioxidant activities. We examined whether GE affects methamphetamine (MA)-induced striatal dopaminergic toxicity in mice. Treatment with MA (7.5 mg/kg, i.p. × 4) resulted in significant decreases in behavioural activity (as shown by locomotor activity and rota rod performance), dopamine level, tyrosine hydroxylase (TH) activity, and TH protein expression (as evaluated by immunocytochemistry and western blot analysis). In addition, MA treatment showed significant increases in lipid peroxidation [as evaluated by 4-hydroxy-2-nonenal (4-HNE) expression and malondialdehyde formation], protein oxidation (as shown by protein carbonyl expression and its formation), and reactive oxygen species (ROS) formation. Treatment with GE significantly attenuates MA-induced behavioural and dopaminergic impairments, and oxidative stresses in a dose-dependent manner. Our results suggest that GE treatment shows anti-dopaminergic effects in response to MA insult via, at least in part, inhibiting oxidative stresses in the striatum of the mice.

Keywords: Gastrodia elata Bl, methamphetamine, dopamine, oxidative stress, GABA receptor, DOPAC, Dopaminergic Toxicity, Tryosine Hydroxylase, Oxidative Burdens