Biogenic amine

Biogenic amines are organic nitrogen compounds derived from amino acids, the building blocks of proteins. They play crucial roles in various biological processes in both animals and plants. In humans, biogenic amines are involved in the central nervous system's functioning, acting as neurotransmitters, and are integral to peripheral organ systems, influencing blood pressure, gastric acid secretion, and more.

Formation and Structure

Biogenic amines are formed by the decarboxylation of amino acids or by amination and transamination of aldehydes and ketones. The structure of biogenic amines consists of an amine group attached to an alkyl chain, which originates from the parent amino acid. Common biogenic amines include Histamine, Serotonin (5-hydroxytryptamine, 5-HT), Dopamine, Norepinephrine, and Epinephrine.

Function

Neurotransmitters

Many biogenic amines, such as dopamine, serotonin, and norepinephrine, function as neurotransmitters in the brain. They are involved in regulating mood, sleep, appetite, and cognition. For example, imbalances in serotonin and dopamine levels are associated with depression and other psychiatric disorders.

Hormonal Actions

Epinephrine and norepinephrine, produced by the adrenal glands, act as hormones. They are critical in the body's fight-or-flight response, increasing heart rate, blood pressure, and blood glucose levels.

Regulatory Functions

Histamine is involved in immune responses and regulates physiological functions in the gut. It also acts as a neurotransmitter in the brain.

Metabolism

The metabolism of biogenic amines occurs primarily in the liver and brain, involving enzymes such as monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT). These enzymes help in the breakdown and inactivation of biogenic amines.

Clinical Significance

Abnormal levels of biogenic amines are linked to various diseases and conditions. For instance, elevated histamine levels can cause allergic reactions, while deficiencies in neurotransmitters like serotonin and dopamine are linked to depression and Parkinson's disease, respectively.

Dietary Sources and Health Risks

Certain foods contain high levels of biogenic amines, such as aged cheeses, wine, and fermented products. Ingesting large amounts can lead to health issues like headaches, hypertension, and allergic reactions in sensitive individuals. This is particularly problematic in individuals with impaired metabolism of these amines due to genetic variations or inhibitory drugs.

See Also

• Neurotransmitter
• Amino Acid
• Decarboxylation
• Monoamine Oxidase
• Catechol-O-methyltransferase