Oxidative stress and inhibitors of a monoamine oxidase compound design based on natural products: A multitarget strategy for Alzheimer’s and Parkinson’s diseases

Oxidative stress, one of many problems facing living organisms, is produced by free radicals and reactive oxygen species (ROS) and occurs due to an imbalance between endogen antioxidant defenses and these ROS. Free radicals and ROS are highly reactive and have a short halflife; thus, these features cause numerous oxidative reactions with biomolecules like membrane lipids or DNA. Indeed, ROS are particularly active in the brain and neuronal tissues, which presents a problem in treating neurodegeneration diseases, like Alzheimer’s and Parkinson’s. A key enzyme in both diseases is monoamine oxidase, which catalyzes neurotransmitter oxidation and produces hydrogen peroxide from that process. Currently, due to the oxidative stresses involved, there is research into dual therapies for neurodegenerative diseases. In this context, nature plays a key role in the development of new dual-drugs, as is the case of phenolic compounds. These compounds may dually inhibit monoamine oxidase and be strong antioxidants. In addition, with scientific advances in neurodegenerative disease treaments, there may be novel synergies among new and old compounds and these enzymes (MAO-A and MAO-B). This text discusses the effects of oxidative stress, antioxidant activities and the benefit of this feature, nature as a source of antioxidant and monoamine oxidase inhibitors, and finally, the development of new drugs from natural products based on structural similarities, and the use of molecular docking for explaining the different activities of tested compounds.