Test pour la taxonomie
Common treatments used to treat pain may be making things worse by triggering a change to chronic pain in some people.
Chronic pain is known to arise from acute pain, and a paper in Science Translational Medicine elucidates how this happens.
According to study co-author Jeffrey Mogil, PhD, “For many decades it’s been standard medical practice to treat pain with anti-inflammatory drugs. But we found that this short-term fix could lead to longer-term problems.” Mogil is a professor of psychology at McGill University and E. P. Taylor Chair in Pain Studies.
The researchers studied immune cells from 98 people with low back pain (LBP) and mice to study the mechanisms mediating the transition from acute to chronic pain.
Following the human subjects for three months, researchers used transcriptomics—a technology that allows for the study of all an organism’s RNA transcripts.
Upon entry to the study, patients with LBP entered the study recorded their pain scores, and genome-wide transcriptomics were done during the acute phase of their pain. At a three-month follow-up, the patients were divided into two groups: those with resolved pain and those who continued to have persistent pain. Transcriptomics studies were repeated, and the results between the two groups were compared.
The study found neutrophil activation-dependent inflammatory genes were up-regulated in subjects with resolved pain, but there were no changes seen in patients with persistent pain. This suggests neutrophils—a type of white blood cell that are part of the immune system and help fight infection—lead to beneficial inflammation.
The study was replicated in patients with temporomandibular disorder (TMD), resulting in similar findings.
In additional research conducted in mice with induced injuries, researchers performed a series of tests to investigate the effects of a variety of anti-inflammatory and analgesic treatments and pain responses over time.
In brief, it was found that in the mice, anti-inflammatory treatments prolonged pain duration. Intriguingly, the effect was abolished when the researchers administered neutrophils.
Overall, “These results indicate the importance of the up-regulation of inflammatory response at the acute stage of musculoskeletal pain as a protective mechanism against the development of chronic pain,” the study said.
