Alexander B. Niculescu

To date, no clinical laboratory tests for mood disorders exist. Psychiatrists currently rely on reports of patients themselves, but patients with mood disorders can be unsure of how ill they are. So an objective test of the severity of the disorder would be welcome indeed. And that's just what Indiana University School of Medicine researchers are beginning to develop.

Alexander B. Niculescu, assistant professor of psychiatry, medical neurobiology, and neuroscience at the IU School of Medicine Institute of Psychiatric Research, is lead author on a study published in the journal Molecular Psychiatry. Along with colleagues from IU and from Scripps Research Institute and the University of California, San Diego, Niculescu isolated biomarkers in blood that identify mood disorders, a breakthrough that may change the way bipolar illness is diagnosed and treated.

"Although psychiatrists have been aware that bipolar illness and other psychiatric conditions produce molecular changes in the brain, there was no way to measure those changes while the patient was living," Niculescu says. "Blood now can be used as a surrogate tissue to diagnose and assess the severity of the illness. This discovery is a major step towards bringing psychiatry on par with other medical specialties that have diagnostic tools to measure disease states and the effectiveness of treatments."

The researchers measured differences in blood samples from 96 subjects with bipolar disorder. Some had a low mood and some had a high mood at the time the blood was drawn. Niculescu and his colleagues were looking for differences in the blood of people who were in high mood states vs. low mood states.

The researchers discovered that molecular changes in the brain are reflected in the blood, producing biomarkers whose levels correlated with the severity of the symptoms. They found a panel of 10 biomarkers present in differing amounts in individuals suffering from high or low mood states. The concentration of the blood markers also varied depending on the severity of the depression or mania the individual was experiencing.

According to Niculescu, who is also a staff psychiatrist at the Richard L. Roudebush VA Medical Center, this discovery could have an impact on treatments for a wide range of mood disorders, including post-partum depression and post-traumatic stress disorder. The initial research was supported by National Institutes of Health grant funding, NAESAD, and funds from Eli Lilly and Co. The Indiana University researchers are planning a larger study looking at the mood markers in response to treatments, and they will use their methodology to seek biomarkers for other psychiatric diseases.