Monoamine oxidase A enzyme; Monoamine oxidase B enzyme (MAO-A (for Monoamine oxidase A), MAO-B (for Monoamine oxidase B))

Monoamine oxidase A and B enzymes are mitochondrial, flavin-containing enzymes crucial for the breakdown (oxidative deamination) of neurotransmitters such as serotonin, norepinephrine, dopamine, and dietary amines including tyramine and phenethylamine. MAO-A (encoded by MAOA) preferentially metabolizes serotonin, norepinephrine, and tyramine, and is widely expressed in neural and some non-neural tissues; deficiency results in Brunner syndrome and has been implicated in aggression, psychiatric conditions, and certain cancers. MAO-B (encoded by MAOB) preferentially metabolizes phenethylamine and benzylamine, is abundant in glial cells and platelets, and is important in dopaminergic and neurodegenerative disease processes such as Parkinson's disease. Both enzymes are therapeutic targets: MAO inhibitors (MAOIs) are used as antidepressants and in the treatment of Parkinson’s disease. Safety concerns include interactions with dietary amines and other drugs, and their activity in non-neural tissue has implications for cardiovascular and oncologic disease[1][2][3][4][5][6][8][7].

Other names

MAOAmonoamine oxidase type Aamine oxidase [flavin-containing] A isoform 1/2BRNRSMAOBmonoamine oxidase type Bamine oxidase [flavin-containing] B

Irreversible inhibition of MAO-A and/or MAO-B (classic MAOIs); Reversible inhibition of MAO-A (e.g., moclobemide); Selective inhibition of MAO-B (e.g., selegiline, rasagiline); Increase in central monoamine neurotransmitters by preventing their enzymatic degradation