Monoamine Oxidase (None)

Monoamine oxidases (MAOs) are a family of flavoprotein enzymes (EC 1.4.3.4) that catalyze the oxidative deamination of monoamines, including neurotransmitters and dietary amines. They play a crucial role in regulating the levels of key neurotransmitters such as serotonin, norepinephrine, dopamine, and trace amines within the central nervous system and peripheral tissues. There are two main isoforms: MAO-A and MAO-B. Inhibitors targeting these enzymes—monoamine oxidase inhibitors (MAOIs)—are used clinically to treat depression, Parkinson’s disease, anxiety disorders, among others. By blocking enzymatic activity, levels of mood-regulating neurotransmitters increase, symptoms related to low monoaminergic tone can be alleviated, but there is risk for adverse effects due to accumulation of dietary amines like tyramine (“cheese effect”) or drug interactions with serotonergic agents leading to serotonin syndrome.

Inhibition of monoamine oxidase, leading to increased levels of monoamine neurotransmitters (serotonin, norepinephrine, dopamine) in the synaptic cleft and/or cytosol.