A prominent feature of Alzheimer's disease (AD) is the accumulation of amyloid-β peptide (Aβ) derived from abnormal processing of amyloid precursor protein in senile plaques. Accordingly, reduction in the potentially toxic Aβ has emerged as one of the most important therapeutic goals in treating AD. One potential source of phytotherapeutic agents is berberine (BBR), an alkaloid from Coptis Chinensis.