Tyramine: characteristics of this monoamine-type neurotransmitter

For the proper functioning of the body, we naturally secrete a series of substances that help promote it; others, on the other hand, that we extract from food, and others that we secrete and extreme.

Tyramine is a substance that is part of the latter; it is a monoamine amino acid (neurotransmitter) that helps regulate blood pressure. We also find it in foods such as cheese, nuts or herring.

• Related article: "Types of neurotransmitters: functions and classification"

Tyramine: characteristics of this neurotransmitter

Tyramine is a vasoactive amino acid. This means that it widens (vasodilation) or narrows (vasoconstriction) the blood vessels. It is, specifically, a monoamine, a type of neurotransmitter.

All monoamines are derived from aromatic amino acids such as phenylalanine, tyrosine, tryptophan, and thyroid hormones through the action of aromatic l-amino acid enzymes decarboxylase. tyramine found in some foods such as aged cheese, walnuts, chicken liver, and herrings (belonging to the sardine family).

Regarding its effects, tyramine stimulates the release of the catecholamines adrenaline and norepinephrine. On the other hand, it helps regulate blood pressure, and, in addition to being found in certain foods, it occurs naturally in the body.

tyramine causes headache in some people, and it is a product that is obtained by converting tyrosine (an amino acid present in many proteins) into epinephrine (active hormone produced internally in the adrenal gland).

Pharmacology

At the drug level, it is important to know that antidepressant medications called monoamine oxidase inhibitors (MAOIs) block monoamine oxidase, which is an enzyme that breaks down excess tyramine in the body.

Blocking this enzyme helps alleviate the symptoms of depression. That is why MAOIs are indicated for this type of mood disorders (depression), and especially indicated for atypical depressions.

• You may be interested in: "MAOIs (monoamine oxidase inhibitors): effects and types"

Foods with this substance

Tyramine occurs naturally in small amounts in certain foods that contain protein. As these foods age, tyramine levels rise. On the other hand, tyramine levels can vary among different foods, due to their different processing, storage, and preparation methods. Also, even when cooked, tyramine levels in food cannot be reduced.

Some examples of foods with a high level of tyramine are the following:

• Strong or aged cheeses, such as aged cheddar, Swiss, and Parmesan.
• cured meats, which are meats treated with salt and nitrate or nitrite.
• Smoked or processed meats, such as hot dogs, bologna, bacon, corned beef, or smoked fish.
• Canned or fermented foodssuch as sauerkraut, kimchi, caviar, tofu, or pickles.
• Sauces, such as soy sauce, shrimp sauce, fish sauce, miso, and teriyaki sauce.
• Soy and soy products.
• Peas, broad beans and their pods.
• Dried or overripe fruits, such as raisins or prunes, plantains or overripe avocados.
• Alcoholic beverages, such as beer, especially draft or homemade, red wine, sherry, and spirits.

effects

As we have seen, foods that contain tyramine can cause headaches (migraine), since this substance triggers a chain reaction resulting in the most common causes of headache, such as cerebral vasoconstriction, followed by dilation of the blood vessels in the head.

On the other hand, tyramine could also cause, in particularly sensitive people, arrhythmias and arterial hypertension.

Relationship with MAOIs

If you are following a pharmacological treatment with MAOI-type antidepressants, their combination with foods that contain high levels of tyramine, such as those mentioned, should be avoided.

This is so because if you take an MAOI and eat foods high in tyramine, it can quickly reach dangerous levels, causing a serious increase in blood pressure, which can end up leading to hypertensive crises or heart attacks.

hypertensive crisis

In the event of a rapid and severe increase in blood pressure (with risk of a seizure hypertensive), it is advisable to know the symptoms that may appear (emergency signs), which would include the following: following:

• Intense headache.
• Nausea and vomiting.
• Sweating and severe anxiety.
• Nasal bleeding.
• Rapid heartbeat.
• Chest pain.
• Changes in sight.
• Shortness of breath.
• Confusion.

Bibliographic references:

• Hall-Flavin, D. (2019). Monoamine oxidase inhibitors and diet: is it necessary to restrict tyramine? Mayo Clinic.
• National Headache Foundation. (2007). The Tyramine.
• Stahl, S.M. (2002). Essential Psychopharmacology. Neuroscientific bases and clinical applications. Barcelona: Ariel.