Acetylcholinesterase inhibitors from the toadstool Cortinarius infractus

Inhibition of acetylcholinesterase (AChE) and therefore prevention of acetylcholine degradation is one of the most accepted therapy opportunities for Alzheimer's disease (AD), today. Due to lack of selectivity of AChE inhibitor drugs on the market, AD-patients suffer from side effects like nausea or vomiting. In the present study the isolation of two alkaloids, infractopicrin (1) and 10-hydroxy-infractopicrin (2), from Cortinarius infractus Berk. (Cortinariaceae) is presented. Both compounds show AChE-inhibiting activity and possess a higher selectivity than galanthamine. Docking studies show that lacking pi-pi-interactions in butyrylcholinesterase (BChE) are responsible for selectivity. Studies on other AD pathology related targets show an inhibitory effect of both compounds on self-aggregation of A beta-peptides but not on AChE induced Ab-peptide aggregation. Low cytotoxicity as well as calculated pharmacokinetic data suggest that the natural products could be useful candidates for further drug development. (C) 2010 Elsevier Ltd. All rights reserved.