Dr. AA Badway, from Cardiff Metropolitan University (Wales, UK), published an article which points to the essential amino acid tryptophan as a possible key to developing new antidepressant serotonin-boosting drugs to treat Major Depressive Disorder.

The article, published in July 2013, focused on Major Depressive Disorder, which is also known as clinical depression, unipolar depression, or recurrent depression. This mental disorder causes pervasive, persistent low moods, where the patient can no longer experience pleasure in normally enjoyable activities. It is usually also accompanied by low self-esteem.

Major Depressive Disorder is an extremely debilitating condition which greatly impacts quality of life. Major Depressive Disorder affects private and work life, impacting eating habits, sleeping habits, and general overall health. In some cases, the disorder has led to suicide.

Serotonin deficiency is one of the causes of Major Depressive Disorder. Serotonin is a neurotransmitter, a chemical messenger that transmits signals between the brain and the body. Serotonin has many effects, including the regulation of moods.

Treatment for Major Depressive Disorder includes antidepressant medications which cause the synthesis of serotonin, and thus these medications have a mood stabilizing effect.

Serotonin is synthesized in the body by the amino acid tryptophan.

Tryptophan’s role in serotonin synthesis

Tryptophan is one of the essential amino acids, which means we must obtain it from our food. Tryptophan is widely available in most proteins, like eggs, fish, meat, soybeans, and sesame seeds.

There are several factors which cause decreased levels of tryptophan, and which result in the serotonin deficiencies which could cause Major Depressive Disorder. One factor, accelerated degradation of tryptophan in the liver, is one of the factors which must be addressed when developing new antidepressants.

The article concluded that enhancing the availability of tryptophan to the brain will result in normalized levels of serotonin synthesis, and could form the basis for new antidepressant drugs.