diaminooxidáz

Diaminooxidase, often abbreviated as DAO, is an enzyme that plays a crucial role in the metabolism of biogenic amines, particularly histamine. It is a copper-containing enzyme and is primarily found in the small intestine, kidneys, and placenta. The main function of DAO is to catalyze the oxidative deamination of amines, breaking them down into less biologically active compounds.

In humans, DAO is responsible for the degradation of dietary histamine and histamine released from mast cells in the body. This process is essential for preventing the accumulation of histamine, which can lead to various physiological effects. When DAO activity is insufficient, it can result in histamine intolerance, a condition characterized by symptoms such as headaches, digestive issues, skin reactions, and respiratory problems after consuming histamine-rich foods or experiencing histamine release.

The gene encoding diamino oxidase is known as AOC1. Variations in this gene have been associated with differences in DAO enzyme activity and susceptibility to histamine intolerance. While DAO is the primary enzyme for histamine breakdown in the gut and circulation, another enzyme, histamine N-methyltransferase (HNMT), handles histamine metabolism in other tissues.