涩里番

Nerve injuries can have long-lasting effects on the immune system that appear to differ between males and females, according to preclinical research from 涩里番.

Nerve injuries are common and can happen from stretching, pressure or cuts. They can have lasting consequences, including chronic pain. While the immune system typically helps repair the damaged area, shows that nerve injuries can also disrupt the body鈥檚 entire immune system.

Analysis of blood samples from mice revealed signs of widespread inflammation throughout the body after a nerve injury. To the researchers鈥� surprise, male and female mice reacted very differently.

Males and females respond differently to nerve damage

In male mice, inflammation markers in the blood rose as expected and stayed high. But in female mice, those markers didn鈥檛 increase at all. Yet when blood from male and female mice with nerve injuries was transferred into healthy mice, it caused increased pain sensitivity in both cases. This suggests that something in the blood 鈥� though different between the sexes 鈥� spreads the pain response throughout the body.

鈥淭hat means whatever is causing pain in females is working through a completely different biological pathway that we don鈥檛 yet understand,鈥� said co-author Jeffrey Mogil, E.P. Taylor Professor of Pain Studies at 涩里番 and a Distinguished James 涩里番 Professor.

鈥淏y understanding how men and women react differently to nerve injuries, we can work toward more personalized and effective treatments for chronic pain,鈥� added Sam Zhou, the study鈥檚 lead author and a PhD student at 涩里番.

Broader implications

The study provides evidence that nerve injuries can have wide-reaching effects, not just tissue damage at the injury site. Long-term immune system changes may increase the risk of many chronic diseases, including chronic pain and related conditions such as anxiety and depression.

鈥淩ecognizing the full impact of nerve injuries is important for both doctors and patients,鈥� said Dr. Ji Zhang, the senior author and a professor at 涩里番鈥檚 Department of Neurology and Neurosurgery and Faculty of Dental Medicine and Oral Health Sciences. 鈥淎 localized nerve injury can affect whole body. Men and women may respond differently.鈥�

About the study

鈥溾�� by Sam Zhou, Xiang Shi, Alain Zhang, Magali Millecamps, Jeffrey Mogil and Ji Zhang was published in Neurobiology of Pain. The study was funded by the Canadian Institutes of Health Research and the Louise and Alan Edwards Foundation.