Potential anticholinesterase activity of edible plantas with popular medicine uses.

FABIANI, C.; WENZ, J.J.; ANTOLLINI, S.S.

Rio de Janeiro

Congreso; IBRO 9th Word Congress; 2015

Cholinergic deficit is an important factor responsible for Alzheimer?s disease symptoms. Acetylcholinesterase (AChE), an enzyme that hydrolyzes acetylcholine molecules at the synaptic cleft, is one of the molecular targets for the treatment of this disease. AChE inhibitors interfere with the breakdown of ACh and prolong its action. Furthermore, oxidative stress has been identified as an early event in the pathogenesis of Alzheimer, and antioxidant molecules have been shown to mitigate the cognitive decline and decrease its progression. Thus, the goal of the present work was to identify novel compounds with dual effects: inhibition of AChE and antioxidant activity. To this end, we tested extracts from six edible plants used in traditional medicine. Inhibition of AChE activity was evaluated in methanolic extracts obtained from leaves of Peumus boldus Loser (boldo), Laurus nobilis (laurel), Lippia turbinata Grisebach (poleo), Rosmarinus officinalis (rosemary), Camellia sinensis (read tea) and Tilia platiphyllos (linden). Our results revealed that, among these plants, P. boldus and C. sinensis produced the strongest inhibition of AChE. Also, both extracts showed high antioxidant activity when tested by the radical scavenging power (DPPH) and the reducing power assays. The presence of phenolic and flavonoid compounds was detected in both extracts. The methanolic extracts of P. boldus and C. sinensis were then fractionated with n-hexane, dichloromethane, ethyl acetate, n-butanol, and water. For both P. boldus and C. sinensis the hexane phase contained the main AChE inhibitory activity whereas the acetate and n-butanolic phases contained the main antioxidant power as well as the main proportion of phenolic and flavonoid compounds. Thus, the antioxidant activity of these extracts directly correlated with phenolic and flavonoid compounds and not with the AChE inhibitory activity. Hydrophobic compounds with potential AChE inhibitory activity were discovered. Our results imply that P. boldus and C. sinensis have great potential as sources for new active principles in the treatment of Alzheimer?s disease. This work establishes the initial step in the development of potential drugs for the treatment of Alzheimer?s disease and further evaluation is required.