In vitro anti-β-secretase and dual anti-cholinesterase activity of Camellia sinensis L. (tea) relevant to treatment of dementia

The primary target of licensed drugs for the treatment of Alzheimer's disease is the inhibition of the enzyme acetyleholinesterase, although preventing beta-amyloidosis is a prime target for drugs in development. The in vitro dual anti-cholinesterase and beta-secretase activities of Camellia sinensis L. extract (tea) is reported. Green and black tea inhibited human acetylcholinesterase (AChE) With IC50 values of 0.03 mg/mL and 0.06 mg/mL respectively, and human butyrylcholinesterase (BuChE) with IC50 values 0.05 mg/mL. Green tea at a final assay concentration of 0.03 mg/mL inhibited beta-secretase by 38%. These novel findings suggest that tea infusions contain biologically active principles, perhaps acting synergistically, that may be used to retard the progression of the disease assuming that these principles, yet to be identified, reach the brain. Copyright (C) 2004 John Wiley Sons, Ltd.