Researchers at Rush University Medical Center, in collaboration with researchers at Northwestern University, have identified a molecular mechanism central to the development of osteoarthritis (OA) pain, a finding that could have major implications for future treatment of this often-debilitating condition.
An article describing the research was published in the Dec. 11 print version of the Proceedings of the National Academy of Sciences.
According to the Arthritis Foundation, an estimated 27 million Americans live with OA, but, despite the frequency of the disease, its cause is still not completely known and there is no cure. In fact, many different factors may play a role in whether or not you get OA, including age, obesity, injury or overuse and genetics.
The researchers elevated the levels of this protein in one group of mice with simulated OA and the mice exhibited signs that they were experiencing pain — for example, avoiding climbing and other movement that would typically trigger pain. Another group of mice with simulated knee joint damage, but without the protein, did not exhibit the pain-avoidance behaviors.
"This method essentially provides us with a longitudinal 'read-out' of the development of OA pain and pain-related behaviors, in a mouse model," said Anne-Marie Malfait, MD, PhD, associate professor of biochemistry and of internal medicine at Rush, who led the study.
New insight into the mechanisms of pain caused by OA may one day lead to new treatments to reduce pain for a growing population of OA sufferers.
"This is an important contribution to the field of osteoarthritis research. Rather than looking at the cartilage breakdown pathway in osteoarthritis, Dr. Malfait and her colleagues are looking at the pain pathway, and this can take OA research into a novel direction that can lead to new pain remedies in the future," said Dr. Joshua Jacobs, professor and chairman of orthopedic surgery at Rush University Medical Center.