Scientists have discovered a novel way to block pain at its source.
A research team at The University of Texas Health Science Center at San Antonio says that a substance similar to capsaicin, which gives chili peppers their heat, is generated at the site of pain in the human body.
And blocking the production of this substance can stop chronic pain, the team found.
Capsaicin is the primary ingredient in hot chilli peppers, which causes a burning sensation.
It does this by binding to receptors present on the cells inside the body.
Similarly, when the body is injured, it releases capsaicin-like substances - fatty acids called oxidized linoleic acid metabolites or OLAMs - and these, via receptors, cause pain, the researchers have found.
Dr Kenneth Hargreaves, senior researcher at the Dental School at the University of Texas, and his team next set out to see if they could block these newly discovered pain pathways.
Lab work on mice showed that by knocking out a gene for the receptors, there was no sensitivity to capsaicin.
Armed with this knowledge they set about making drugs to do the same.
"This is a major breakthrough in understanding the mechanisms of pain and how to more effectively treat it. We have discovered a family of endogenous capsaicin-like molecules that are naturally released during injury, and now we understand how to block these mechanisms with a new class of non-addictive therapies," Dr Hargreaves said.
Ultimately, he hopes the drugs will be able to treat different types of chronic pain, including that associated with cancer and inflammatory diseases such as arthritis and fibromyalgia.
The findings were published April 26 in the Journal of Clinical Investigation.