Further research could lead to a better understanding of how to boost the opioid response in people who are depressed to reduce the exaggerated effect of social stress and to increase the benefits of positive social interactions, researchers say.
“Every day we experience positive and negative social interactions. Our findings suggest that a depressed person’s ability to regulate emotions during these interactions is compromised, potentially because of an altered opioid system,” says lead author David Hsu, formerly of University of Michigan and now at Stony Brook University.
“This may be one reason for depression’s tendency to linger or return, especially in a negative social environment. This builds on our growing understanding that the brain’s opioid system may help an individual feel better after negative social interactions and sustain good feelings after positive social interactions.”
New Medication Targets
For the study, researchers focused on the mu-opioid receptor system in the brain—the same system that has been studied in relation to response to physical pain. During physical pain, the brain releases opioids to dampen pain signals.
The new work, published in the journal Molecular Psychiatry, shows that this same system is associated with an individual’s ability to withstand social stress and to positively respond to positive social interactions.
“Social stressors are important factors that precipitate or worsen illnesses such as depression, anxiety, and other neuropsychiatric conditions,” says senior author Jon-Kar Zubieta, research professor of depression at University of Michigan. “This study examined mechanisms that are involved in the suppression of those stress responses.
“The findings suggest novel potential targets for medication development that directly or indirectly target these circuits, and biological factors that affect variation between individuals in recovery from this otherwise chronic and disabling illness.”
Rejection and Acceptance
The new findings have already prompted the team to plan follow-up studies to test individuals who are more sensitive to social stress and vulnerable to disorders such as social anxiety and depression, and to test ways of boosting the opioid response.
“Of course, everyone responds differently to their social environment,” Hsu says. “To help us understand who is most affected by social stressors, we’re planning to investigate the influence of genes, personality, and the environment on the brain’s ability to release opioids during rejection and acceptance.”
