The catechol-O-methyltransferase inhibitory potential of Z-vallesiachotamine by in silico and in vitro approaches

Abstract

Z-Vallesiachotamine is a monoterpene indole alkaloid that has a β-N-acrylate group in its structure. This class of compounds has already been described in different Psychotria species. Our research group observed that E/Z-vallesiachotamine exhibits a multifunctional feature, being able to inhibit targets related to neurodegeneration, such as monoamine oxidase A, sirtuins 1 and 2, and butyrylcholinesterase enzymes. Aiming at better characterizing the multifunctional profile of this compound, its effect on cathecol-O-methyltransferase activity was investigated. The cathecol-O-methyltransferase activity was evaluated in vitro by a fluorescence-based method, using S-(5′-adenosyl)-l-methionine as methyl donor and aesculetin as substrate. The assay optimization was performed varying the concentrations of methyl donor (S-(5′-adenosyl)-l-methionine) and enzyme. It was observed that the highest concentrations of both factors (2.25U of the enzyme and 100μM of S-(5′-adenosyl)-l-methionine) afforded the more reproducible results. The in vitro assay demonstrated that Z-vallesiachotamine was able to inhibit the cathecol-O-methyltransferase activity with an IC50 close to 200μM. Molecular docking studies indicated that Z-vallesiachotamine can bind the catechol pocket of catechol-O-methyltransferase enzyme. The present work demonstrated for the first time the inhibitory properties of Z-vallesiachotamine on cathecol-O-methyltransferase enzyme, affording additional evidence regarding its multifunctional effects in targets related to neurodegenerative diseases.