Table 1.

Main difference between the two isoforms MAO-A and MAO-B

MAO-A	MAO-B
It preferentially oxidizes nor-epinephrine and serotonin	Preferentially deaminates β-phenylethylamine and benzyl-amine [65, 66]
It is selectively inhibited by clorgyline	Selectively inhibited by l-deprenyl [65, 66]
Both the MAO isoforms have a different tissue distribution. Occurs in cathecholaminergic neurons as well as glia	MAO-B is predominant in the human brain, and is compartmentalized into different cell types. It occurs mainly in glial cells and serotoninergic neurons [67, 68]
MAO-A inhibitors have been used mostly in the treatment of mental disorders, in particular depression and anxiety [80, 81]	Used in the treatment of Parkinson’s disease and perhaps, Alzheimer’s disease [70, 82]