Acetylcholinesterase Inhibitory Effect of Some Medicinal Herbs Used in Iranian Traditional Medicine for Memory Improvement

Abstract

Iranian Traditional Medicine (ITM) has a long history in treatment of disorders mostly by using medicinal plants. “Nesyan” is one of the common diseases in ITM that could be partly comparable with Alzheimer. Since, acetylcholinesterase inhibitors (AChEIs) are the usual drugs for Alzheimer, therefore, in order to find new AChEIs, the plants used in ITM are good candidates. In the present investigation, AChEI activity of nine species used for “Nesyan” in ITM have been investigated. Aqueous and total extracts of Phyllanthus emblica, Urginea maritima, Corylus avellana, Alpinia officinarum, Matricaria chamomilla, Curcuma longa, Crocus sativus, Melissa officinalis and Brassica nigra have been prepared by using infusion and maceration methods, respectively. The extracts were dried and their AChEI activity were assessed by using Ellman method with acetylthiocholine iodide as substrate and dithiodinitrobenzoic acid as reagent in 96-well plates at 405 nm. The results demonstrated that only total extract of Alpinia officinarum showed 41.3% inhibition at concentration of 300 µg/ml. Other extracts had trace or no AChEI properties. It is concluded that among the examined species used in ITM, Alpinia officinarum acts as anti-Alzheimer through AChE inhibition possibly with other mechanisms. In order to find the mechanisms of other plants more investigations are necessary.