Blues clue

Clinically depressed people have lower levels of a naturally occurring amino acid that helps our bodies produce energy, a collaborative study reported.

The findings, published July 30 in the Proceedings of the National Academy of Sciences, mirror results of rodent research into the potential link between depression and levels of the substance, acetyl-L-carnitine.

Natalie Rasgon, MD, PhD, professor of psychiatry and behavioral sciences, called the findings “an exciting addition to our understanding of the mechanisms of depressive illness,” but said large-scale, robust clinical trials are needed to determine any potential role in treatment.

Depression affects 8 to 10 percent of the general population at any given time.

Rasgon shared senior authorship of the study, which analyzed blood samples from 71 adults treated for depression at either of two New York City hospitals. Compared with 45 adults without depression, levels of acetyl-L-carnitine were lower in people with depression symptoms and lowest in people with more severe symptoms.