Researchers at the University of Illinois Chicago (UIC) in the US have identified a biomarker to track depression and antidepressant response.
Found in human platelets, the biomarker can be identified with the help of a blood test and used to track the extent of depression.
The blood test can help to determine the efficacy of antidepressant therapies in individual patients.
UIC stated that the research is developed from previous studies that show depression is consistent with decreased levels of adenylyl cyclase, a small molecule within the cell.
Adenylyl cyclase is made in response to epinephrine and serotonin neurotransmitters.
UIC distinguished professor of physiology, biophysics and psychiatry Mark Rasenick said: “When you are depressed, adenylyl cyclase is low. The reason adenylyl cyclase is attenuated is that the intermediary protein that allows the neurotransmitter to make the adenylyl cyclase, Gs alpha, is stuck in a cholesterol-rich matrix of the membrane – a lipid raft – where they don’t work very well.”
In the new study, titled ‘A Novel Peripheral Biomarker for Depression and Antidepressant Response’, researchers have identified a new cellular biomarker that can translocate Gs alpha from lipid rafts.
In previous research, patients showed improvement in their depression symptoms when Gs alpha was out of the lipid raft.
However, patients who received antidepressants and showed no improvement were observed to have Gs alpha stuck in the lipid raft.
This showed that the presence of antidepressants in the bloodstream was not sufficient to improve depression symptoms on its own.
The UIC researchers noted that a blood test could help to find whether Gs alpha was out of the lipid raft after just one week of treatment.
Rasenick further added: “Most depression is diagnosed in primary care doctor’s offices, where they don’t have sophisticated screening.
“With this test, a doctor could say, ‘Gee, they look like they are depressed, but their blood doesn’t tell us they are. So, maybe we need to reexamine this’.”
Last November, researchers at the University of Central Florida (UCF) developed a device to identify viruses, such as Covid-19, in the human body.