- Researchers have identified an intracellular enzyme, known as NAAA for N-acylethanolamine acid amidase, as playing a key role in causing pain to develop chronically.
- Deactivating this enzyme in the spinal cord 72 hours after peripheral tissue injury stopped the development of chronic pain in mice.
- This makes it possible to consider a treatment other than opioids.
About a third of adults (30%) suffer from chronic pain, according to Inserm. These can be linked to pathology, joint and muscle problems, migraines, etc. They are said to be chronic when they last more than three months. In this case, they are no longer a symptom but become a disease in its own right. American researchers at the University of California recently identified the molecular mechanism that triggers the transition from acute to chronic pain. The study, published on October 22 in the journal Science Advances, allows treatment to be considered in order to prevent this transition.
Identify new drugs
Researchers have identified an intracellular enzyme, known as NAAA for N-acylethanolamine acid amidase, as playing a key role in causing pain to develop chronically. Deactivating this enzyme in the spinal cord 72 hours after peripheral tissue injury stopped the development of chronic pain in mice.
“Delineating the nature, location and timing of events involved in pain chronicity is necessary to identify control nodes in the process that can be targeted by new classes of disease-modifying drugs beyond analgesics., says Daniele Piomelli, professor of anatomy and neurobiology and lead author of the study. This study is the first to identify that NAAA, a previously unrecognized control node, can be effectively targeted by small molecule therapies that inhibit this enzyme and block the transition from acute pain to chronic pain.”
Pain that persists after tissue heals
Chronic pain arises from acute pain caused by the physical trauma of tissue damage. The problem is that it persists long after the tissue has healed and is often resistant to treatment. Treatment largely depends on a handful of classes of pain relieving drugs such as opioids, which can lose their effectiveness over time and can also be addictive.
Nerve damage is considered a critical factor in the transition to chronic pain, but the underlying molecular events leading to its emergence have been poorly understood. “Our results suggest that a new class of drugs, NAAA inhibitors, can be used to treat various forms of chronic pain and to prevent incisional and inflammatory injuries after surgery.”, Concluded Daniele Piomelli.