Diaminoxidase

Diaminoxidase, also known as DAO, is an enzyme that plays a crucial role in the metabolism of amines, particularly histamine. It is found in various tissues throughout the body, including the intestine, liver, and kidneys, and is also present in certain foods. DAO catalyzes the oxidative deamination of primary amines, converting them into their corresponding aldehydes. In the context of histamine, this means that diamine oxidase breaks down ingested histamine, preventing it from being absorbed into the bloodstream and causing adverse reactions.

The enzyme is a copper-containing amine oxidase. Its activity is essential for maintaining proper histamine levels, which are involved in immune responses, digestion, and neurotransmission. A deficiency in diamine oxidase can lead to a buildup of histamine in the body, a condition often referred to as histamine intolerance. Symptoms associated with histamine intolerance can be varied and may include digestive issues, skin reactions, headaches, and respiratory problems.

While diamine oxidase is produced by the body, it can also be consumed through foods like liver, bacon, and aged cheese, though these are often high in histamine themselves. The enzyme's effectiveness can be influenced by various factors, including genetics, certain medications, and gastrointestinal health. Research into diamine oxidase continues to explore its functions and potential therapeutic applications, particularly in managing conditions related to histamine metabolism.