histaminaasi

Histaminase, also known as diamine oxidase (DAO), is an enzyme found in humans and other animals. Its primary function is to catalyze the oxidative deamination of primary amines. In the human body, histaminase plays a crucial role in the metabolism of histamine, a biogenic amine involved in local immune responses, gastric acid secretion, and neurotransmission. It also metabolizes other polyamines like putrescine and cadaverine.

The enzyme is particularly abundant in the small intestine, kidneys, and placenta. In the digestive tract, histaminase is thought to be important for breaking down dietary histamine, thereby preventing potential adverse reactions in individuals with histamine intolerance. The placenta also expresses high levels of histaminase, suggesting its role in protecting the fetus from maternal histamine.

Deficiency or reduced activity of histaminase has been linked to conditions like histamine intolerance, characterized by symptoms such as headaches, hives, digestive upset, and nasal congestion after consuming histamine-rich foods. While histaminase is a significant enzyme in amine metabolism, research into its precise roles and therapeutic applications is ongoing.