Potential therapeutic agents from Philippine medicinal plants against Alzheimer's disease

Abstract

AbstractBackgroundNatural products derived from plants have been in the lead of extensive studies in the search of potential anti‐Alzheimer’s disease agents. These plant species comprised a high chemical diversity of compounds. Natural products and plant extracts as therapeutic agents for AD have demonstrated that they favor neuroprotection against amyloid‐beta cytotoxicity and aggregation. Hence, the identification of plants and their bioactive constituents as a possible source of pharmacologically‐relevant compounds against AD is warranted.MethodA total of 25 Philippine plant extracts were used in the experiment. The cytotoxicity of the extracts was initially determined using the ATP cytotoxicity assay utilizing the SH‐SY5Y and HEK‐293 cell lines. The non‐toxic extracts were subjected to our in‐house multimer detection system (MDS) assay. The procedure utilized three mutant cells, namely, Amyloid Precursor Protein (APP) 669, APP 604, and Presenilin 1 (PSE1 232). ELISA was used to establish whether the extracts and compounds have down‐regulated the aggregation of amyloid‐beta in the mutant cells against a positive control (phenol red) and a negative control (no treatment of cells), and in comparison with the normal HEK‐293 cells.ResultSeveral plant extracts prevented the oligomer aggregation of amyloid‐beta in the mutant cells. These include Pandanus amaryllifolius, Pandanus simplex, Pandanus tectorius, Guettarda speciosa, Lasianthus trichophlebus, and Psydrax puberula. The prevention of oligomer aggregation is statistically different from the negative control. Also, these extracts were non‐toxic to the SH‐SY5Y and HEK‐293 cells. These results suggest that these plants may be developed as potential nutraceuticals to minimize the effects of AD. Currently, we are in the process of identification the bioactive compounds from these plant extracts using chromatographic and spectroscopic techniques.ConclusionThe results in this study can pave the way for the development of new drugs with therapeutic value against AD. These drugs can also be candidates for pre‐clinical and clinical trials and licensing. The compounds can be used as chemical markers for the standardization of health products formulated from these plants. The scientific community including scientists, researchers and students can benefit from the new knowledge and discoveries and the validated protocols for the detection of extracts and compounds against AD.