A team of researchers at Duke University, including three NARSAD Grantees, studied the metabolic profiles of patients with major depression and identified biochemical changes in the patients taking antidepressants who got better. Led by NARSAD Independent Investigator Grantee, Rima Kaddurah-Daouk, Ph.D., the team worked with 75 patients with major depressive disorder who either took a selective serotonin reuptake inhibitor (SSRI) antidepressant or placebo. After one week and four weeks of taking the SSRI or placebo, they measured improvement in symptoms of depression, and blood samples were taken and analyzed. The results of this work were published on July 17, 2013 in the journal PLOS ONE.

The researchers found changes in a neurotransmitter pathway connected to the pineal gland, the part of the endocrine system that controls the sleep cycle, in patients taking the SSRI who responded to the treatment; these changes were not found in those who did not respond to the antidepressant. “This study revealed that the pineal gland is involved in mechanisms of recovery from a depressed state,” said Dr. Kaddurah-Daouk, Associate Professor of Psychiatry and Behavioral Sciences at Duke Medicine and leader of the Pharmacometabolomics Research Network. “We have started to map serotonin which is believed to be implicated in depression, but now realize that it may not be serotonin itself that is important in depression recovery. It could be metabolites of serotonin that are produced in the pineal gland that are implicated in sleep cycles.”

"Metabolomics is teaching us about the differences in metabolic profiles of patients who respond to medication, and those who do not," she went on to say. "This could help us to better target the right therapies for patients suffering from depression who can benefit from treatment with certain antidepressants, and identify, early on, patients who are resistant to treatment and should be placed on different therapies."

Other NARSAD Grantees involved in the study include Ranga R. Krishnan, M.B., Ch.B., Dean of the Duke-NUS Graduate Medical School and John A. Rush, M.D.,Vice Dean, Clinical Sciences, Duke-NUS Graduate Medical School.

Read more about this research which may lead to more effective depression treatments.