MOLECULE

Tyramine

Tyramine is a monoamine compound derived from the amino acid tyrosine. It is a very strong basic compound (based on its pKa). Tyramine is metabolized by the enzyme monoamine oxidase. In foods, it is often produced by the decarboxylation of tyrosine during fermentation or decay. Foods containing considerable amounts of tyramine include fish (herring), chocolate, alcoholic beverages, cheese, yogurt, soy sauce, sauerkraut, and processed meat. Tyramine in the blood or urine is often considered as a biomarker for the consumption of cheese. A large dietary intake of tyramine can cause an increase in systolic blood pressure of 30 mmHg or more and induce migraine headaches (PMID: 27424325). The tyramine connection to hypertensive episodes was discovered by a British pharmacist whose wife was taking an monoamine oxidase inhibitors (MAOI). He noticed that every time they had a meal with cheese, she would get a severe headache (PMID: 19742203). Tyramine acts as a neurotransmitter via a G protein-coupled receptor called TA1, which has a high affinity for tyramine. The TA1 receptor is found in the brain as well as peripheral tissues including the kidney. As an indirect sympathomimetic compound, tyramine can also serve as a substrate for adrenergic uptake systems and monoamine oxidase, so it prolongs the actions of adrenergic transmitters. Tyramine also provokes transmitter release from adrenergic terminals.