"It's not in your head, and you're not weak. It's your immune system." Geoffroy Laumet, lead author of this work published Friday in the journal, confirms this. Immunology Science. Led by Michigan State University in the United States, these studies highlighted the role of certain immune system cells in pain resolution. But also, and perhaps more importantly, they revealed that this mechanism functioned much more effectively in men than in women.
"There are real biological reasons why women suffer from prolonged pain," Mr. Laumet, the lead researcher at the laboratory, insists to AFP. And while these reasons are probably varied, one of the leads revealed by his team lies in the action of a type of white blood cell.
An identified biological mechanism
They discovered in mice that a subcategory of immune cells left the blood to travel to injured tissues and release "a molecule that silences pain-sensitive neurons" explains Mr. Laumet. This effect was more pronounced in male mice due to a well-known sex hormone, testosterone, which appeared as "promoting the production by these white blood cells of the molecule that calms neurons," the researcher explains.
This biological mechanism was subsequently observed in human patients who had suffered physical trauma, such as a road accident. Researchers measured the levels of these specific white blood cells and the molecule suspected of alleviating pain in their blood and discovered that these levels were significantly higher in men than in women.
And although injured men and women reported comparable levels of initial pain after their trauma, this pain then decreased significantly more rapidly in men than in women.
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This discovery fills us with joy "a significant gap" in our understanding of pain
This discovery fills us with joy "a significant gap" "This advances our understanding of pain," Elora Midavaine, a researcher at the University of California and a specialist in chronic pain, told AFP. "if the differences between the sexes in terms of pain are well documented"the underlying mechanisms still largely "Misunderstood", notes this expert who did not participate in the study.
By shedding light on this mechanism, researchers could pave the way for new treatments. This avenue of research offers hope because, while numerous painkillers are currently available, no ideal treatment exists for chronic pain or for women.
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Several studies have indeed highlighted differences in response to painkillers, with opioids, for example, not appearing to be as effective in women as in men. It will likely take years to arrive at a suitable therapeutic solution, but Geoffroy Laumet hopes that this research will, in the meantime, lead to improvements. "to help dispel this widespread idea that women's pain is exaggerated."
Long neglected and minimized by the medical profession, women's pain was indeed considered to be the responsibility of "the emotional" rather than as something of"rooted in biology""This prejudice has only recently begun to be dismantled," recalls Elora Midavaine. "Thanks in particular to the inclusion of women and female subjects in clinical research over the last few decades. But as this study shows, things are..." "changing" the researcher assures.
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