Serotonin levels could lead to early detection.
A new study out of the Medical University of Vienna has found that depression can be detected by performing a blood test. A team of researchers led by Lukas Pezawas indicates that biomarkers in the blood may be useful for diagnosing the illnesss.
While many people become depression for short periods of time, clinical depressive states are actually mental illnesses. Depression is an illness that can interfere with daily life. In addition to feelings of extreme sadness, clinical depression is accompanied by many symptoms, such as anger, loss of interests, appetites changes, and concentration problems. Doctors do not know exactly what causes depression, though it is understood as a result of chemical changes in the brain. Before the study conducted by Pezawas, there has been no way to determine the existence of the illness through regular blood tests.
Low serotonin levels have often been linked to depression. Serotonin is a molecule that is regarded as a mood regulator. Serotonin transporter proteins are responsible for serotonin getting where it needs to go in the cells. Sometimes serotonin transporter proteins will reabsorb the serotonin, which acts like a clogged drain – the signal is unable to move onto the next neuron. Physicians target serotonin transporter proteins by prescribing selective serotonin reuptake inhibitors (SSRIs), which prevents a cell from reabsorbing the serotonin. SSRIs regulate the flow of serotonin in the brain, thus improving mood.
Studies have shown that the serotonin transports in the blood works in exactly the same way as in the brain. In the blood, it ensures that blood platelets maintain the appropriate concentration of serotonin in the blood plasma.
The researchers, who published their findings in PLOS ONE, used a functional MRI to determine how readily the cells in the blood took serotonin. They then related this to the depression neural network. This network is termed the ‘default mode network’, because it is active at rest and processes content with strong self-reference.
A very strong correlation was found between the two. This could mea that monitoring serotonin levels in the blood could potentially be used as a diagnostic tool.
“This is the first study that has been able to predict the activity of a major depression network in the brain using a blood test,” said Pezawas in a press release. He also said that using the test “could become reality in the not too distant future.”
Also, by diagnosing on a biological basis, this could ensure that a patient is getting a proper dose of medication to create the best possible result.
Although the results of this study are promising, depression is very multifaceted and many factors other than serotonin levels contribute to the illness. It may take time before a fully reliable blood test could detect depression, but this is certainly a start.
Originally published May 8, 2014.
