Evaluation of Nootropic and Anti-Nociceptive Activity of Green Tea in Comparison with Medhya Rasayana

Abstract

Green tea (Camellia sinesis) is a known traditional medicinal plant that has been consumed for its putative nutritional and health benefits for centuries. The polyphenols found in green tea are epicatechin, epicatechin-3- gallate, epigallocatechin, and epigallocatechin-3-gallate (EGCG), comprise 30-40 percent of the extractable solids of dried green tea leaves. Green tea polyphenols have demonstrated significant antioxidant activity. In the present study aqueous extract of green tea (10 ml/kgp.o), methanolic extract of green tea (5 ml/kg p.o) and standard Piracetam (150 mg/kg body weight p.o) were used to evaluate the Nootropic activity. Its behavioral studies on mazes like Elevated plus Maze, Morris Water Maze and avoidance behavior on step down type passive avoidance models were performed, whole brain acetyl cholinesterase enzyme activity was also estimated. For evaluating the analgesic activity, analgesic models like hot plate and acetic acid induced writhing were performed. Methanolic extract of green tea showed significant (p<0.01) change in evaluation parameters like transfer latency and step down latency when compared with the aqueous extract of green tea. Methanolic extract of green tea showed better antinociceptive activity in acetic acid induced writhing model (41.6%) when compared to hot plate method (6.64%). Whole Brain acetyl cholinesterase enzyme activity was performed and the results indicated that the methanolic extract of green tea (p<0.01) has better nootropic activity than aqueous extract. The results proved that the methanolic extract of green tea has better Nootropic and anti-nociceptive activity when compared with the aqueous extract of green tea. Methanolic extract of green tea also proved to be superior to the marketed product, Medha rasayana as a memory enhancer.