Propoxur (2-isopropoxyphenyl N-methylcarbamate) is widely used as an
acaricide in agriculture and public health programs. Studies have shown that sub-chronic exposure to
propoxur can cause oxidative stress and immuno-suppression in rats.
Carbamates are also known to exhibit inhibitory effect on
cholinesterase activity, which is directly related to their
cholinergic effects. In the present study, the effect of Withania somnifera (
Ashwagandha), a widely used herbal
drug possessing anti-stress and immunomodulatory properties was studied on
propoxur-induced
acetylcholine esterase inhibition and impairment of cognitive function in rats. Male Wistar rats were divided into four groups. Group I was treated with
olive oil and served as control. Group II was administered orally with
propoxur (10 mg/kg b.wt.) in
olive oil, group III received a combination of
propoxur (10 mg/kg b.wt.) and W. somnifera (100 mg/kg b.wt.)
suspension and group IV W. somnifera (100 mg/kg b.wt.) only. All animals were treated for 30 days. Cognitive behaviour was assessed by transfer latency using elevated plus maze. Blood and brain
acetylcholine esterase (AChE) activity was also assessed.
Oral administration of
propoxur (10 mg/kg b.wt.) resulted in a significant reduction of brain and blood AChE activity. A significant prolongation of the acquisition as well as retention transfer latency was observed in
propoxur-treated rats. Oral treatment of W. somnifera exerts protective effect and attenuates AChE inhibition and
cognitive impairment caused by sub-chronic exposure to
propoxur.