Evaluation of the Anti-amyloidogenic Potential of Nootropic Herbal Extracts in Vitro

Alzheimer’s disease (AD) is characterized by the abnormal aggregation of amyloid ß (Aß) peptide into insoluble fibrils called amyloid plaques. Preventing this process of fibrillization may offer effective therapy for treatment of AD. The aim of the present study is to investigate the effect of methanolic extracts of 13 plant species which are known to be brain boosters in Ayurvedic system of medicine. Our study addressed the influence of these extracts on (i) prevention of aggregation of Aß and (ii) dissociation of preformed Aß fibrils. The aggregation status was monitored by thioflavin T fluorescence assay. The results showed that extracts from Bacopa monneria, Centella asiatica, Convolvulus pluricaulis, Withania sominfera, Nardostachys jatamansi and Glycirrhiza glabra exhibited promising activity by preventing Aß fibril formation/ retention thus identifying Aß as the molecular target for their action. These findings prompt further studies to isolate the active ingredients from these extracts to ultimately determine their therapeutic potential in AD treatment.