In Silico Protein-Ligand Interaction Study of Selected Phytochemicals Against Monoamine Oxidase-B

Parkinson’s disease (PD) is a progressive neurodegenerative disease associated with the death of dopaminergic neurons in the substantia nigra pars compacta. Monoamine oxidase B (MAO-B) inhibitors lessen the degree of PD but still present various side effects. Natural products such as morin, piceatannol, resveratrol, and gallic acid are vital phytochemicals from plants with numerous health benefits. This in silico study aimed to identify potent natural MAO-B inhibitors that could serve as better alternatives to the known MAO-B inhibitors (rasagiline and selegiline). The crystal structure of MAO-B (PDB ID: 2C65) was retrieved from the Protein Data Bank (RSCB) and prepared for molecular docking via Discovery Studio 2020 software. Molecular docking between MAO-B and morin, piceatannol, resveratrol, gallic acid, rasagiline, and selegiline utilised the PyRx software. The Discovery Studio 2020 software was used for visualization. The SwissADME server was used to study the physiochemical properties (Lipinski rule of five), pharma-cokinetic parameters, and absorption, distribution, metabolism, elimination, and toxicity (ADMET) profiles of morin. Comparing results with binding affinity indicated that morin (-10.0 kcal/mol) has a superior potency against 2C65 than piceatannol (-9.0 kcal/mol), resveratrol (-807 kcal/mol), dopamine (-6.4 kcal/mol), gallic acid (-6.3 kcal/mol), rasagiline (-8.0 kcal/mol), and selegiline (-7.4 kcal/mol). Drug candidates comply with all five of Lipinski’s drug-likeness rules with appropriate ADMET properties. Overall, the molecular docking results suggest that morin may be considered a suitable therapeutic candidate for PD treatment.