We have previously demonstrated that nobiletin from the peels of Citrus depressa has the potential to improve cognitive dysfunction in Alzheimer's disease. In the present study, considering a choline theory for the development of Alzheimer's disease, inhibitory effects of 6 citrus polymethoxyflavones, such as nobiletin, 5-demethylnobiletin, 6-demethoxynobiletin, 3'-demethoxynobiletin, 8-demethoxynobiletin and 6,3'-di(demethoxy)nobiletin, on the activity of human acetylcholinesterase (AChE) were assessed in vitro, and the structure-activity relationships were examined. Human AChE activities in the presence and absence of each chemical were spectrophotometrically measured according to the modified Ellman's method with acetylcholine iodide as a substrate of AChE, and their inhibitory effects were assessed. Nobiletin, 8-demethoxynobiletin, and 6-demethoxynobiletin, but not the 3 other chemicals, showed definitely inhibitory effects on AChE activity, and their inhibitory activities (60∼76 % of control at 100 μM of each compound) were almost the same. Methoxyl substituents at both the 5 and 3' positions of the nobiletins were demonstrated to be essential for showing the inhibitory effect on AChE activity.
|Number of pages||4|
|Publication status||Published - 2011|
- Alzheimer's disease
ASJC Scopus subject areas
- Pharmacology, Toxicology and Pharmaceutics(all)