Converting maslinic acid into an effective inhibitor of acylcholinesterases

• Published in: European journal of medicinal chemistry 2015-10, Vol.103, p.438-445
• Main Authors: Schwarz, Stefan, Loesche, Anne, Lucas, Susana Dias, Sommerwerk, Sven, Serbian, Immo, Siewert, Bianka, Pianowski, Elke, Csuk, René
• Format: Article
• Language: English
• Subjects: Acetylcholinesterase; Acetylcholinesterase - metabolism; Alzheimer disease; Animals; Augustic acid; Butyrylcholinesterase; Cells, Cultured; Cholinesterase Inhibitors - chemical synthesis; Cholinesterase Inhibitors - chemistry; Cholinesterase Inhibitors - pharmacology; Dose-Response Relationship, Drug; Electrophorus - metabolism; Fibroblasts - drug effects; Maslinic acid; Mice; Molecular Docking Simulation; Molecular Structure; NIH 3T3 Cells; Structure-Activity Relationship; Triterpenes - chemical synthesis; Triterpenes - chemistry; Triterpenes - pharmacology
• ISSN: 0223-5234; 1768-3254
• DOI: 10.1016/j.ejmech.2015.09.007

During the last decade, maslinic acid has been evaluated for many biological properties, e.g. as an anti-tumor or an anti-viral agent but also as a nutraceutical. The potential of maslinic acid and related derivatives to act as inhibitors of acetyl- or butyryl-cholinesterase was examined in this communication in more detail. Cholinesterases do still represent an interesting group of target enzymes with respect to the investigation and treatment of the Alzheimer's disease and other dementia illnesses as well. Although other triterpenoic acids have successfully been tested for their ability to act as inhibitors of cholinesterases, up to now maslinic acid has not been part of such studies. For this reason, three series of maslinic acid derivatives possessing modifications at different centers were synthesized and subjected to Ellman's assay to determine their inhibitory strength and type of inhibitory action. While parent compound maslinic acid was no inhibitor in these assays, some of the compounds exhibited an inhibition of acetylcholinesterase in the single-digit micro-molar range. Two compounds were identified as inhibitors of butyrylcholinesterase showing inhibition constants comparable to those of galantamine, a drug often used in the treatment of Alzheimer's disease. Furthermore, additional selectivity as well as cytotoxicity studies were performed underlining the potential of several derivatives and qualifying them for further investigations. Docking studies revealed that the different kinetic behavior within the same compound series may be explained by the ability of the compounds to enter the active site gorge of AChE. [Display omitted] •In this study we investigated a variety of derivatives of maslinic acid.•Maslinic acid could be converted into a selective inhibitor for acetylcholinesterase.•The compounds are no substrates for other hydrolytic enzymes.•The compounds show rather low cytotoxicity.•Their activity is similar to that of standard compound galantamine.