Oxidative stress has been reported to induce
cognitive impairment in
Parkinson's disease. This paper aimed to determine the effect of
quercetin, a substance possessing
antioxidant activity, on the cognitive function in a rat model of
Parkinson's disease. Male Wistar rats, weighing 200-250 g, were orally given
quercetin at doses of 100, 200, 300 mg/kg BW once daily for a period of 14 days before and 14 days after the unilateral lesion of right substantia nigra induced by
6-hydroxydopamine (6-OHDA). Their spatial memory was assessed at 7 and 14 days of treatment and neuron density was determined,
malondialdehyde (MDA) level, the activity of
superoxide dismutase (SOD),
catalase (CAT), and
glutathione peroxidase (GPx) were evaluated at the end of the experiment. In addition, the activity of
acetylcholinesterase (AChE) was also measured. It was found that all doses of
quercetin enhanced spatial memory. Therefore, it is suggested that the cognitive-enhancing effect of
quercetin occurs partly because of decreased oxidative damage resulting in increased neuron density.