A Comprehensive Review on Compounds and Herbal Approaches against Amyloid Beta Aggregation in Alzheimer's Disease

Alzheimer's disease is a neurodegenerative disorder that affects brain cells over time, progressively reducing cognitive function, interfering with memory retention, and making daily tasks more difficult. The development of amyloid-beta (Aβ) plaques plays an important role in the progression of the disease, contributing to neurological swelling and cognitive impairment. Aβ induces oxidative damage and produces anti-inflammatory cytokines while reducing the association with vascular RAGE and acetylcholine. This article aims to present the latest and relevant research on treatment approaches targeting amyloid beta, including synthetic compounds, phytomolecules, and plant extracts. Novel delivery approaches are also covered. Memantine, latrepirdine, somatostatin, diosgenin, cirsiliol, amentoflavone, luteoloside, and many other synthetic compounds have been reported to generally inhibit Aβ aggregation, thereby reducing plaque development. Phytomolecules such as brazilin, (+)-catechin, ginnalin A, bacoside-A, bakuchiol, curcumin, homotaurine, icariin, genistein, fucosterol, and quercitrin also alleviate symptoms via various mechanisms. Additionally, plant extracts from Annona atemoya, Lycium barbarum, Humulus lupulus, Oroxylum indicum, Salvia macilenta, Trichosanthis Semen, Camellia sinensis, Betula utilis, Cirsium japonicum, Elaeagnus glabra, Orthosiphon aristatus, Metasequoia glyptostroboides, Zizania latifolia, and Benincasa hispida are discussed briefly with their mechanisms of action. The present review also addresses the pathogenesis, risk factors, symptoms, and diagnosis of amyloid beta aggregation. Data were collected from PubMed, ScienceDirect, SciFinder, Scopus, and Google Scholar.