Avaliação da inibição da acetilcolinesterase por extratos de plantas medicinais

Abstract

Palavras-chave: extrato aquoso, extrato etanólico, inibição enzimática ABSTRACT: Evaluation of acetylcholinesterase inhibition by extracts from medicinal plants.In this study, we evaluated the inhibitory activity against acetylcholinesterase (AChE) according to Ellman's method, modified by Rhee, for ethanol and aqueous extracts from eight plants used in folk medicine in the northeast region of Brazil. E. velutina aqueous extract did not have inhibitory activity, while Maytenus rigida aqueous extract showed low inhibitory activity (percentage of inhibition of 4%). Moderate inhibitory activity was detected for Phoradendron piperoides aqueous extract (percentage of inhibition of 40%), while V. agnus castus L. extract inhibited 74% AChE activity, characterized as a potent inhibitory activity. Evaluation of AChE inhibition by ethanol extracts indicated that the extracts from Sideroxylon obtusifolium, Erythrina velutina, Vitex agnus-castus L., Phoradendron piperoides, Chrysobalanus icaco, Bauhinia cheilantha and Orbignya phalerata did not show inhibitory activity. A low inhibitory activity was observed for ethanol extracts from Maytenus rigida (percentage of inhibition of 7%) and Hyptis fruticosa (percentage of inhibition of 11%). Moringa oleifera ethanol extract showed moderate inhibitory activity, inhibiting 47% of the activity of this enzyme. None of the tested ethanol extracts showed potent inhibitory activity against AChE. Results of the studies of acetylcholinesterase inhibition allow the conclusion that V. agnus-castus L. aqueous extract showed to be most effective in inhibiting AChE. This result reinforces the need for continued study of this extract in order to make the partition and the purification of fractions to isolate the molecule responsible for the observed inhibition.

Potencial bioativo de ervas-de-passarinho: Efeito do extrato aquoso de folhas de Phoradendron piperoides (Kunt.) Trel. (Santalaceae) na mitose

“…Os resultados dos efeitos mitóticos do extrato EAFPp estão na Tabela 1. (Dias et al, 2007); interferência no trânsito intestinal (Marçal, Almeida & Carvalho, 2007) e na atividade da acetilcolinesterase, induzidos por compostos presentes em extratos vegetais, inibindo-a moderadamente (Mota et al, 2012). Efeitos na mitose em raízes de A. cepa foram constatados por diferentes autores (Bezerra & Oliveira, 2016;Bastos et al, 2017;Akwu et al, 2019;Rieder et al, 2019).…”

“…piperoides no trânsito intestinal em camundongos, reduzindo as contrações significativamente, o que, em hipótese, pode ser devido a um bloqueio de influxo de cálcio através dos canais de cálcios e à ativação do setor adrenérgico. Mota et al (2012) detectaram atividade inibitória moderada (40%) da acetilcolinesterase com o extrato aquoso de P. piperoides. Em duas outras espécies de Phoradendron (P. microphyllum e P. mucrunatum), Bastos et al (2017) identificaram presença de alcalóides e outros compostos como diterpenos, triterpenos, esteróis, álcoois, aldeídos, ácidos graxos e hidrocarbonetos.…”

“…Há vários estudos que abordam propriedades e bioatividades proporcionadas por extratos da espécie Phoradendron piperoides, os quais revelam: -efeitos miorelaxantes, antiespasmódicos e, baixa toxicidade aguda do extrato aquoso foliar, sem efeito antinociceptivo em animais cobaias-camundongos (Dias et al, 2007); -atividades antinociceptiva, anti-inflamatória e antioxidante produzidas pelo extrato metanólico, o que requer a identificação e o isolamento dos componentes bioativos (Vasconcellos et al, 2009); -indícios de efeitos antidiabéticos de componentes encontrados na planta (Rostron, 2014;Rodriguez et al, 2008); -efeito inibitório de 40% da atividade da acetilcolinesterase (AChE) apenas do extrato aquoso foliar e, sem este efeito, sobre a enzima, do extrato etanólico (Mota et al, 2012); -altos potencias antioxidantes (> 75%) nas composições polares (extrato metanólico bruto, fração acetato de etila e partição metanólica) (Vasconcellos et al, 2009);atividade antimicrobiana do extrato diclorometado da planta inteira, mas inibindo em menos de 50% o crescimento de Mycobacterium tuberculosis em cultura radiométrica (Graham et al, 2003).…”

Bioactivity and Toxicity of Senna cana and Senna pendula Extracts

“…The drugs available at present are effective only in the early stages of AD, whose period is very short. Therefore, it is important to search for new drugs of natural origin that inhibit the enzyme acetylcholinesterase (AchE), both in the early stages and advanced stages of AD [31, 32]. …”

The Confrontation between Ethnopharmacology and Pharmacological Tests of Medicinal Plants Associated with Mental and Neurological Disorders

“…There is a growing evidence from in vitro, animal, and clinical studies reporting that medicinal plants might be beneficial for treating various mental and neurological disorders including Alzheimer disease, depression, anxiety, and insomnia [ 363 – 366 ]. For neurological disorders, in particular, pharmacological tests have shown promising results in the reduction of side effects when using plants with known therapeutic effects in the treatment of some types of dementia [ 18 , 22 , 367 – 372 ]. Medicinal plants have been sought as an alternative therapy [ 18 , 373 – 375 ] owing to the inefficacy of some industrial medications on certain diseases, such as degenerative ones.…”