A team of researchers from UCSD’s School of Medicine, Stony Brook University and other institutions published a pilot study this week on how short-term stress can cause molecular alterations in immune responses.
Using tandem skydiving as the simulated psychological stressor, the researchers employed a range of biological measurements to determine the physiological and molecular responses to acute stressors, including RNA isolation and several kinds of gene expression analysis.
The experiment’s participants were all healthy first-time divers who had blood and saliva samples taken at specific intervals, once at a week and an hour before, and then one day after skydiving. The results showed an increase in natural killer cells, an immune response that kills tumor cells and virus-infected cells.
First co-author of the study and assistant project scientist at UCSD Nadejd Beliakova-Bethell explained another finding of the study — gender-specific differences in the molecular stress response.
“The results from our study point to a possibility that the differences in the immune cell response to stress at the [RNA level] vary between men and women,” Beliakova-Bethell told the UCSD Guardian.
Beliakova-Bethell elaborated on how genetic differences that are associated with stressful events may be linked to physical ailments, showing how psychological stress can manifest itself in tangible ways.
“Co-expressed genes associated to specific immune pathways were identified,” Beliakova-Bethell said. “Further studies would be needed to validate association of these pathways with stressful life events and incidences of heart disease, post-traumatic stress disorder and possibly other diseases in men and in women. ”
Brinda Rana, co-author of the paper and associate professor in the department of psychiatry at UCSD’s School of Medicine, described how stress functions as a protective mechanism.
“Stress is how your body reacts to harmful events or environments,” Rana told the Guardian. “During an acute stress, a biochemical reaction is triggered in your body to prepare you and your body to prevent injury.”
According to Beliakova-Bethell, the type of stressful events, unique to students, could produce immune responses similar to those found in the study.
“Students may experience both short-term and long-term stress in the course of their studies,” Beliakova-Bethell said. “Taking an exam may be a short-term stress for some people, if they stress in anticipation of the test on that day. On the other hand, stressing about an exam throughout the review period, worrying about not being able to complete all the necessary requirements for obtaining a degree, and even being away from family constitute long-term stress that may result in adverse consequences, such as anxiety and depression.”
For many students, college can be a stressful experience. The National College Health Assessment estimated that about a third of college students had difficulty functioning in the last year due to depression, while over half said they felt overwhelming anxiety in 2013.
UCSD’s own Counseling and Psychological Services produced a short video about stress management. The video includes suggestions such as eating healthier, being active and setting realistic short-term goals that demonstrate the relationship between state of mind and physical well-being, similarly to how the study found psychological stressors to have physiological impacts.
Beliakova-Bethell highlighted the ways psychological stress affects the body over time at the molecular level, resulting in physical maladies.
“As opposed to acute stress, chronic stress over weeks, months or years has detrimental effects, such as suppression of the immune response,” Beliakova-Bethell said. “The result may be inability to adequately respond to pathogens, hence increased susceptibility to infectious diseases, such as flu or common cold.”
Rana said that the newer, advanced technologies will allow for further follow-up studies that focus at the molecular level of stress.
“[These studies are] just getting started,” Rana told the Guardian, “And as we start applying these new technologies, we’ll learn a lot more about how stress at the molecular level impacts the cells, the tissues and the physiology of the subjects.”