Sustainable Use of Various Amaryllidaceae Plants Against Alzheimer's Disease

Abstract

Alzheimer's Disease (AD), a slowly progressive neuropsychiatric illness, principally characterized by memory deficits, has become the fourth leading cause of death in developed nations. Since the patients with AD suffer from marked reduction of cholinergic neuronal function resulting in a deficiency in acetylcholine (ACh) concentration in the brain, and these reductions are associated with impairments in memory, cholinergic enhancement strategies have been at the forefront of efforts to palliate pharmacologically the cognitive symptoms. Therefore, treatment approaches have been focused on the acetylcholinesterase inhibitors (AChEI) which are the most promising drugs demonstrating efficacy in the treatment of AD. Since, recently, galanthamine, an alkaloid isolated from different Galanthus species (Amaryllidaceae), has been found to be a potent and reversible acetylcholinesterase inhibitor, this development has prompted us to investigate the anticholinesterase activity in other plant species of Amaryllidaceae growing in Turkey, namely Galanthus elwesii, G. ikariae, Narcissus tazetta subsp. tazetta, Leucojum aestivum and Pancratium maritimum by Ellman method in comparison with galanthamine as the standard drug. Bioactivity-directed fractionation and isolation studies carried out on G. ikariae and N. tazetta subsp. tazetta extracts afforded 8 Amaryllidaceae-type alkaloids in total. We found that the activity of both of the plant extracts was due to the synergistic interaction of the alkaloids isolated. a Values were expressed as mean ± SEM p>0.05:-, p<0.05: + , p<0.01: ++ , p<0.001: +++

Cholinesterase inhibitors from botanicals

“…Most of the compounds having potential anticholinesterase activity are isolated from Buxaceae, Amaryllidaceae, Lycopodiaceae, Lamiaceae, Chenopodiaceae, Papaveraceae, Apocynaceae , and Labiatae species. [ 13 17 18 25 27 29 45 59 ] Following are three of the imporant families having potential compounds to be used as anticholonesterase inhibitors.…”

Medicinal plants with cholinesterase inhibitory activity and their applications

“…The acetyl-cholinesterase inhibiting rates were: lycorine 43.69%, tazettine 36.34%, galanthamine 48.00%, 3epihydroxybulbispermine 30.18% N-nor-galanthamine 34.09% and haemanthamine 20.8 %. Chloroform: methanol extract and crude alkaloid extract of the plant were also possessed acetyl-cholinesterase inhibiting activity (46.62±0.77 and 46.96±0.08%, respectively) (98)(99) .…”

Biological Activities of Snowdrop (Galanthus spp., Family Amaryllidaceae)

“…Rhee et al (2003) showed that the methanol extract of G. nivalis had 96% inhibition against AChE (Rhee et al, 2003). Chloroform:methanol (1 : 1) extracts of the bulbs of G. elwesii and G. ikariae inhibited AChE at 73.18 and 75.56% (10 μg/ml), comparable to the alkaloid extracts at 77.23 and 76.96% (10 μg/ml) (Orhan and S ¸ener, 2005). Phytochemical study of alkaloid extract of G. ikariae yielded amaryllidaceae-type alkaloids, including lycorine (IC 50 3.16 µM), tazettine, crinine, galanthamine (IC 50 3.2 µM), 3-epi-hydroxybulbispermine and 2demethoxymontanine.…”