University of Florida researchers suggest in a new study that specific genetic markers that put people at risk for depression may also predict who might benefit from exercise.
The researchers note in the study, published recently in The Journal of Frailty & Aging, that men who were carriers of two specific genes—the brain-derived neurotrophic, or BDNF, gene, and a serotonin transporter gene—had the most significant response to exercise.
They then suggest that physical activity as part of a treatment plan could help the carriers of these genes, according to a media release from University of Florida.
Study co-author Vonetta Dotson, PhD, an assistant professor in the College of Public Health and Health Profession’s department of clinical and health psychology, and her team looked at data gathered in the Lifestyle Interventions and Independence for Elders, or LIFE, pilot study, in which 396 sedentary older adults were separated into two groups: those who received health education classes and those who were given moderate physical activity classes for 12 months.
Although a prior study published from the data suggested that exercise did not significantly affect depression symptoms among all the participants, the suggestion changed when the researchers studied the data further, per the release.
“When we looked at subgroups, we ended up finding significant response to exercise in men who were carriers of a specific gene.” Dotson says in the release.
To assess the participants’ response to exercise, they took a test called the Center for Epidemiologic Studies Depression Scale, a screening test for depression and depressive disorders, at the beginning of the LIFE study, and again 12 months later. The Depression Scale assesses factors such as sadness and fearfulness, loss of appetite and concentration difficulties, a diminished capacity to experience pleasure, or perceived difficulties in social relationships.
The participants also underwent genetic testing before participating in the study. Three genes in particular were tested: the brain-derived neurotrophic, or BDNF, gene, a serotonin transporter gene, and a gene called apolipoprotein E, the release explains.
The researchers found the greatest decrease in symptoms such as loss of appetite and concentration difficulties in men who carried the BDNF genetic variation that predisposed them to depression. They also saw an increase in the capacity to experience pleasure in men who exercised regularly who carried specific variations of the serotonin transporter gene, per the release.
According to Dotson in the release, the study provides evidence that physical activity could be explored as an intervention for depression. However, she warns that this study did not include people whose symptoms were severe enough to be formally diagnosed with clinical depression. It’s also important to understand the benefits of exercise because of the impact medications may have on the brains of older adults, she continues.
“I’m trying to understand how exercise versus antidepressants affect the brain,” Dotson adds. “The next step for me is to understand from a brain standpoint who is going to benefit and how exercise is going to be beneficial in addition to or as an alternative to medication.”
[Source(s): University of Florida, EurekAlert]