An association between biological changes on the cellular level and both childhood adversity and psychiatric disorders was identified by researchers. These changes in the form of telomere shortening and alterations of mitochondrial DNA (mtDNA), are important in the aging process.
In a new study published online in Biological Psychiatry, researchers from Butler Hospital identify an association between biological changes on the cellular level and both childhood adversity and psychiatric disorders. These changes in the form of telomere shortening and alterations of mitochondrial DNA (mtDNA), are important in the aging process, and this new research provides evidence that psychosocial factors--specifically childhood adversity and psychiatric disorders-- may also influence these cellular changes and could lead to accelerated aging.
Mitochondria convert molecules from food into energy that can be used by cells and also play a key role in cellular growth, signaling, and death. Telomere shortening is also a measure of advanced cellular aging. Recent studies have examined the possible connection between mitochondria and psychiatric disorders, but the research is very limited, and no prior work has examined the relationship of mitochondrial DNA to psychosocial stress. "We are interested in these relationships because there is now clear evidence that stress exposure and psychiatric conditions are associated with inflammation and health conditions like diabetes and heart disease. Identifying the changes that occur at a cellular level due to these psychosocial factors allows us to understand the causes of these poor health conditions and possibly the overall aging process." said Audrey Tyrka, MD, PhD, Director of the Laboratory for Clinical and Translational Neuroscience at Butler Hospital and Associate Professor of Psychiatry and Human Behavior at Brown University.
Tyrka and fellow researchers recruited 299 healthy adults from the community for the study. Participants completed diagnostic interviews to assess psychiatric disorder diagnosis, and assess childhood adversities, including parental loss, and childhood abuse and neglect. Participants were categorized into four groups based upon the presence or absence of childhood adversity and the presence or absence of lifetime depressive, anxiety, or substance use disorders. Using standard techniques, researchers extracted DNA from whole blood samples for each participant and quantified telomere length and mtDNA copy number, a measure of mitochondrial DNA content.