Investigation of NADPH-Oxidase’s Binding Subunit(s) for Catechin Compounds Induce Inhibition

Abstract

Catechins are natural polyphenolic compounds with ability to minimize excess free radicals through different mechanisms including inhibition of NADPH oxidase (NOX) activity. NOX is a complex enzyme made-up of several subunits, where molecules including catechins binds to exert their effect. Hence, the attempt to probe the NOX enzyme’s binding subunit of catechins-induce effect. Several in-silico techniques were deployed in probing the NOX enzyme’s binding subunit of the catechins. The catechins were downloaded from PubChem database in SDF files. The five NOX subunits with PDB ID: 3A1F, 1OV3, 1HH4, 1OEY, and 7CFZ were downloaded from the protein databank. Drug-likeness properties and biological activities were predicted using ADMETMESH software. Catechin-NOX subunits’ interactions was performed via molecular docking, and the docked conformations were analyzed using Protein-plus software. The results of the study predicted the catechin compounds; epicatechin (E), epicatechin gallate (EG) and epigallocatehin gallate (EGG) are drug-like in nature and possess enzymes inhibitory properties. Docking result predicted catechins are capable of interacting with the various NADPH oxidase (NOX) subunits but in a varied degree. Their (catechins) strongest affinities was predicted on p40phox and p67phox PB1 subunit (PBD: 1OEY) with binding energies in the ranges of -8.3 to -9.9kcal/mol in this order; Apocynin>EGG>EG>E. While a weak affinity was predicted between the catechin compounds and gp91 (phox) subunit (PDB: 3A1F) with binding energies (-4.9 to -6.5 kcal/mol) in this sequence; E<apocynin<EGG<EG. In conclusion, the study predicted catechin compounds possess drug-likeness properties and has affinities for interaction with NADPH-oxidase subunits particularly the p40phox and p67phox PB1 probably to exert their antioxidant effects. Therefore, in vitro and in vivo study is recommended to verify this claim.