Alleviative effect of scopolamine-induced memory deficit via enhancing antioxidant and cholinergic function in rats by pinostrobin from Boesenbergia rotunda (L.)

Pinostrobin, a key bioactive compound found in the medicinal plant Boesenbergia rotunda (L.), has been noted for its beneficial biological properties including antioxidant, anti-inflammation, anti-cancer and anti-amnesia activities. In view of this, the present study purposed to evaluate the neuroprotective potential of pinostrobin in reversing scopolamine-induced cognitive impairment involving oxidative stress and cholinergic function in rats. A total of 30 male Wistar rats were randomly divided into five groups (n=6): Group 1 received vehicle as a control, group 2 received vehicle + scopolamine (3 mg/kg, i.p.), group 3 received pinostrobin (20 mg/kg, p.o.) + scopolamine, group 4 received pinostrobin (40 mg/kg, p.o.) + scopolamine and group 5 received donepezil (5 mg/kg, p.o.) + scopolamine. Treatments were administered orally to the rats for 14 days. During the final 7 days of treatment, a daily injection of scopolamine was administered. Scopolamine impaired learning and memory performance, as measured by the novel object recognition test and the Y-maze test. Additionally, oxidative stress marker levels, acetylcholinesterase (AChE) activity, choline acetyltransferase (ChAT) and glutamate receptor 1 (GluR1) expression were determined. Consequently, the findings demonstrated that the administration of pinostrobin (20 and 40 mg/kg) markedly improved cognitive function as indicated by an increase in recognition index and by spontaneous alternation behaviour. Pinostrobin also modulated the levels of oxidative stress by causing a decrease in malondialdehyde levels accompanied by increases in superoxide dismutase and glutathione activities. Similarly, pinostrobin markedly enhanced cholinergic function by decreasing AChE activity and promoting ChAT immunoreactivity in the hippocampus. Additionally, the reduction in GluR1 expression due to scopolamine was diminished by treatment with pinostrobin. The findings indicated that pinostrobin exhibited a significant restoration of scopolamine-induced memory impairment by regulating oxidative stress and cholinergic system function. Thus, pinostrobin could serve as a potential therapeutic agent for the management of neurodegenerative diseases such as Alzheimer's disease.