Scientists have discovered a blood compound linked to suicidal ideation, a finding that could have major implications for personalized medicine and treatments. Researchers at the University of California, San Diego have discovered biomarkers related to mitochondrial dysfunction, which interferes with the "conversation" between cells and may be a factor in suicidal tendencies. While suicide is a complex problem that includes a wide range of factors such as trauma and stress, being able to identify those most at risk can be an important diagnostic tool.
Robert Naviaux, a professor at the University of California, San Diego, said: "The effects and drivers of mental illnesses such as depression extend far beyond the brain. About 10 years ago, it would have been difficult to study how the chemistry of the entire body affects our behavior and mental state, but modern technologies such as metabolomics are helping us listen to the conversations that cells are having in their native language: biochemistry."
Earlier this year, scientists discovered a molecular link to suicidal ideation, suggesting some people with depression may be at greater risk. Research on blood markers began in 2019.
For the study, researchers analyzed the blood of 99 adults with depression and suicidal tendencies who had failed traditional treatments, as well as 99 "healthy" participants with no history of mental illness. While hundreds of different biochemicals were found in the blood of key people, five specific biochemicals were identified as key factors in resistance to depression and suicidal ideation.
The identified metabolomics responsible for the disruption of cell-to-cell communication originate from mitochondria. Mitochondria are known as the "power chambers" of cells, and they promote the production of ATP energy, which is necessary for the human body. These five biochemicals were consistent in men and women, and they appeared to alter this process in the depressed group.
"Mitochondria are one of the most important structures in our cells, and alterations in mitochondrial function can trigger a range of human diseases," Navijax said. "When ATP is inside the cell, it acts like an energy source, but outside the cell, it is a danger signal that activates dozens of protective pathways in response to certain environmental stressors. We hypothesize that suicide attempts may actually be part of a larger physiological urge to halt a stress response that has become intolerable at the cellular level."
Now, researchers hope the findings will lead to more personalized mental health treatments and find a target for drugs to help people who don't respond to current clinical treatments.
"If we had 100 people who were not depressed or who were depressed and suicidal, we could correctly identify 85-90 of them who were most at risk based on five metabolites for men and another five metabolites for women," Naviaks said. "This could be important diagnostically, but it also opens up a broader conversation in the field about what exactly causes these metabolic changes."
Among the metabolites identified, some are currently found in supplements such as folic acid and carnitine. This also provides researchers with an exciting new avenue of research.
"None of these metabolites is a magic bullet that can completely reverse depression," Navio said. "However, our findings tell us there are things we can do to steer metabolism in the right direction and help patients respond better to treatment."
The study was published in the journal Translational Medicine.