Native Medicinal Valerian Plants and Their Effects on Acetyl and Butyryl Cholinesterases.

NATALIA COLETTIS ; RAFAEL ALEJANDRO RICCO; MARCELO LUIS WAGNER; CAROLINA MARCUCCI; BEATRIZ GRACIELA VARELA; GOBEC STANISLAV; HERNÁN GERÓNIMO BACH ; DAMIJAN KNEZ; MARIEL MARDER

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

SAIC, SAIB, SAI, SAFE, SAP, SAB, SAFIS, SAA, SAH

It has been shown that acetylcholinesterase (AChE) activity is increased in patients with Alzheimer?s disease (AD), whereas expression and concentration of butyrylcholinesterase (BChE) is compensatory and is increased. Three out of the four approved drugs for the treatment of AD are AChE inhibitors (donepezil/galantamine/rivastigmine); however, they present undesired side effects due to AChE inhibition in peripheral and autonomous nervous systems. They could be overcome by selective inhibition of BChE.Our country harbours several thousands of plant species, which lack scientific information although many of them are used in folk medicine. Our hypothesis is that native plants have unexplored compounds with multiple biological activities on central nervous system.Herein we studied the capacity of hydroalcoholic (70%) extracts (underground parts, 10 %) from 5 Argentinian valerianas: V. carnosa, V. macrorhiza, V. clarionifolia, V. effusa and V. ferax, and V. officinalis (as the reference plant) (Caprifoliaceae) to inhibit AChE/BChE (from mice brain homogenate/plasma and mAChE/recombinant hBChE) by using the Ellman´s method. V. clarionifolia and V. macrhoriza ethanolic extracts inhibited AChE (IC50 (95% confidence interval): 1.29 (0.81-2.05) mg/ml and 1.08 (0.49-2.37) mg/ml, respectively). Although, main effects were observed on BChE, as V. clarionifolia, V. macrorhiza and V. carnosa showed IC50 of 1.86 (1.43-2.43) µg/ml; 82.04 (66.43-101.30) µg/ml and 1.46 (0.99-2.14) mg/ml; respectively. Moreover, even a better inhibition was observed with a partial purification step (ethyl ether extracts) from these three Valerianas´ ethanolic extracts (IC50: 0.57 (0.41-0.81) µg/ml; 4.53 (3.79-5.43) µg/ml and 263.60 (164.60-422.00) µg/ml; respectively). Similar inhibitory profiles were observed with both recombinant and murine enzymes. Our results showed that Argentinian Valerians are promising tools for the discovery of novel native herbal products for the treatment of AD.