MAOA and Alzheimer disease: In fact, these extracts inhibited key enzymes of AD and PD involved in cholinergic metabolism, such as acetyl- and butyryl-cholinesterase (AChE and BuChE, respectively), and aminergic neurotransmission, such as monoamine oxidases (MAO)-A/B, while also reducing Aβ 1–40 aggregation [8,32,33].