Among different sources that contribute in the global oxidative stress, the vast majority of cellular reactive oxygen species (ROS) originate from mitochondrial compartments. Recently, monoamine oxidases (MAOs) are identified as a prominent source of ROS. Monoamine oxidases are localized in the outer membrane of mitochondria and exist as two different isoforms, MAO-A and MAO-B. MAOs are mitochondrial flavoenzymes responsible for oxidative deamination of biogenic amines and during this process, H 2 O 2 and aldehydes are generated as intermediate products. The role of monoamine oxidase in cardiovascular pathophysiology has only recently gained some attention as it is demonstrated that H 2 O 2 and aldehydes may target myocardial function and consequently cardiac function. Results obtained by different research groups showed that MAO-A plays a key role in the regulation of physiological cardiac function and in the development of acute and chronic heart diseases through two mechanisms: regulation of substrate concentration and intracellular production of ROS. In this review, we will focus on the role of MAO-A in the field of cardiac aging and related diseases.
Monoamine oxidase-A (MAO-A), a pro-oxidative enzyme catalyzes the oxidative deamination of endogenous and exogenous monoamines/neurotransmitters like dopamine, serotonin, norepinephrine or tyramine and converting them into their corresponding aldehydes and reactive oxygen species (ROS). Hyperactivity of MAO-A has been shown to be involved in depression, neuro-degeneration including Parkinson’s and Alzheimer’s diseases, neuropsychiatric disorders and cardiovascular diseases. Our recent results however demonstrated the involvement of MAO-A in promoting aggressiveness of lung carcinoma. We found both constitutive and inducible expression of MAO-A in non-small cell lung cancer cells H1299 and in A549 lung epithelial carcinoma cells. By using knockout (by CRISPR-Cas9 gene editing technology) or knockdown (using MAO-A specific esiRNA) MAO-A cells we demonstrated the role of MAO-A in promoting lung cancer aggressiveness and epithelial to mesenchymal transition (EMT). From our observations, we can conclude that MAO-A may be considered as a potential therapeutic target for the intervention and treatment of lung carcinoma.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.