Researchers identify safer pathway for pain relief

(Press-News.org) University of Florida scientists have helped identify a novel drug compound that selectively activates pain-altering receptors in the body, offering a potentially safer alternative to conventional pain medications.

In a new study published in Nature Communications, researchers describe how this drug compound provides pain relief without the dangerous side effects commonly associated with opioids administered to patients. The National Institutes of Health funded the study.

The human body relies on three kinds of opioid receptors to regulate pain, much like traffic control systems on a busy highway. Understanding these pathways is key to developing safer pain treatments. Medications working at mu receptors stop pain traffic to provide rapid relief, but with risks like dangerous respiratory depression and addiction. Most current pain medications target the mu receptor, but UF researchers are pioneering a new strategy focused on the delta opioid receptor, which could offer pain relief with fewer side effects.

“Delta receptors are located throughout the body on pathways and neurons that transmit pain signals to the brain,” said Jay McLaughlin, Ph.D., a professor of pharmacodynamics in the UF College of Pharmacy. “Unlike mu receptors, activating delta receptors does not cause respiratory depression. If we can develop drugs that safely target the delta receptor, we might achieve effective pain relief without the lethal concerns.”

The need for safer pain treatments is urgent. According to the Centers for Disease Control and Prevention, nearly a fourth of U.S. adults experienced chronic pain in 2023, with almost one in 10 suffering from pain severe enough to limit daily activities. Studies estimate that the economic burden of chronic pain exceeds $600 billion annually.

“Chronic pain is an ongoing problem that significantly impacts quality of life,” McLaughlin said. “With an aging population, it’s urgent that we identify new pain therapies that minimize harmful side effects.”

For the past three years, a team of scientists at UF, Washington University in St. Louis and the University of Southern California has been studying how opioid receptors work and applying those insights to develop better and safer pain medications.

The main problem with delta receptors has been the potential for seizures, which has stopped these treatments from being widely used. The research team found a way around this by modifying an existing drug to target a specific area of the delta receptor, giving it the ability to provide pain relief without the harmful effects of traditional opioids.

“Applying new insights into receptor function, our novel compound demonstrated pain-relieving effects in mouse models without major opioid-related side effects like respiratory depression,” McLaughlin said. “This is a significant advance in science, because if we can design safer medications using this approach, it could extend beyond pain relief to treating heart disease, blood pressure and other conditions regulated by receptors with similar functional features.”

McLaughlin emphasized that additional research and clinical trials are needed to validate the safety and effectiveness of targeting delta opioid receptors for treating pain.

END