Screening of Indian medicinal plants for acetylcholinesterase inhibitory activity

Abstract

The cholinergic hypothesis of Alzheimer's disease (AD) has provided the rationale for the current pharmaco-therapy of this disease, in an attempt to reduce the cognitive decline caused by cholinergic deficits. Nevertheless, the search for potent and long-acting acetylcholinesterase (AChE) inhibitors that exert minimal side effects in AD patients is still ongoing. AChE inhibitors are currently the only approved therapy for the treatment of Alzheimer's disease; only a limited number of drugs are commercially available. Hydroalcohol extracts of six herbs, Andrographis paniculata, Centella asiatica, Evalvulus alsinoides, Nardostachys jatamansi, Nelumbo nucifera, Myristica fragrans used in Indian systems of medicine, were tested for in vitro acetylcholinesterase inhibitory activity based on Ellman's method in 96-well microplates using AChE obtained from bovine erythrocytes. The results showed that the hydroalcohol extract from Centella asiatica, Nardostachys jatamansi, Myristica fragrans, Evalvulus alsinoides inhibited 50% of AChE activity at concentrations of 100-150 microg/mL. Andrographis paniculata and Nelumbo nucifera extracts showed a weak inhibition of acetylcholinesterase with IC(50) values of 222.41 +/- 19.87 microg/mL and 185.55 +/- 21.24 microg/mL, respectively. Physostigmine was used as a standard and showed inhibition of acetylcholinesterase with an IC(50) value of 0.076 +/- 0.0042 microg/mL.

Biological activities of the hydro-alcoholic and aqueous extracts of <i>Achillea fragrantissima</i> (Forssk.) grown in Jordan

“…A variety of plants has been reported to show AChE inhibitory activity and so may be relevant to the treatment of neurodegenerative disorders such as AD [35]. Using TLC assay method, neither aqueous, nor hydroalcoholic extracts showed AChE inhibition.…”

Facile approach to synthesize magnesium oxide nanoparticles by using Clitoria ternatea—characterization and in vitro antioxidant studies

“…Clitoria ternatea is commonly used as a brain tonic in Ayurvedic system of traditional Indian herbal medicine to ameliorate intelligence and intensify the memory function (Karuna Talpate et al 2014), prevents convulsions as in epilepsy (anticonvulsant) and also as relaxing agent. Various activities of C. ternatea were reported as antioxidant, vascular smooth muscle relaxant and hepatoprotective agent (Mukherjee et al 2007(Mukherjee et al , 2008Kuppan Nithianantham et al 2011). Hence, in the present study, we have evaluated the ethanolic extract of C. ternatea was utilization in green nano MgOÁNPs synthesis and their antioxidant activity.…”

Natural sesquiterpen lactones as acetylcholinesterase inhibitors

“…It was established by Ellman et al (1961) and is based on the reaction of thiocholine (one of the products of enzymatic hydrolysis of acetylthiocholine) with DTNB (Ellman's reagent), forming a yellow product (5-mercapto-2-nitrobenzoic acid and its dissociated forms) at pH 8 which can be detected at 405 nm (Komersova et al 2007). Based on the above mentioned assay, the experiment was conducted according to modified microplate method (Mukherjee et al 2007). All samples were dissolved in methanol in concentration of 3 mg/mL.…”