title: Galangin, a flavonol derived from Rhizoma Alpiniae Officinarum, inhibits acetylcholinesterase activity in vitro.
abstract: Acetylcholinesterase (AChE) inhibitors are widely used for the treatment of Alzheimer's disease (AD). Several AChE inhibitors, e.g. rivastigmine, galantamine and huperzine are originating from plants, suggesting that herbs could potentially serve as sources for novel AChE inhibitors. Here, we searched potential AChE inhibitors from flavonoids, a group of naturally occurring compounds in plants or traditional Chinese medicines (TCM). Twenty-one flavonoids, covered different subclasses, were tested for their potential function in inhibiting AChE activity from the brain in vitro. Among all the tested flavonoids, galangin, a flavonol isolated from Rhizoma Alpiniae Officinarum, the rhizomes of Alpiniae officinarum (Hance.) showed an inhibitory effect on AChE activity with the highest inhibition by over 55% and an IC(50) of 120 microM and an enzyme-flavonoid inhibition constant (K(i)) of 74 microM. The results suggest that flavonoids could be potential candidates for further development of new drugs against AD.
authors.affiliation: Department of Biology and Center for Chinese Medicine, The Hong Kong University of Science and Technology, Clear Water Bay Road, Hong Kong SAR, China. avaguo@ust.hk
authors.forename: Ava J Y
authors.initials: AJ
authors.lastname: Guo
authors.forename: Heidi Q
authors.initials: HQ
authors.lastname: Xie
authors.forename: Roy C Y
authors.initials: RC
authors.lastname: Choi
authors.forename: Ken Y Z
authors.initials: KY
authors.lastname: Zheng
authors.forename: Cathy W C
authors.initials: CW
authors.lastname: Bi
authors.forename: Sherry L
authors.initials: SL
authors.lastname: Xu
authors.forename: Tina T X
authors.initials: TT
authors.lastname: Dong
authors.forename: Karl W K
authors.initials: KW
authors.lastname: Tsim
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D032429:Alpinia / Q000737:chemistry*; D000818:Animals; D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D004353:Drug Evaluation, Preclinical; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D051381:Rats; D027343:Rhizome / Q000737:chemistry*
chemical_list: D002800:Cholinesterase Inhibitors; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; C037032:galangin; D000110:Acetylcholinesterase