Think back to the last time your cut your finger or skinned your knee. There was acute pain, but eventually that subsided as your body worked to repair the damage. After a few days, the injury was healed and pain from that incident was nothing but a memory.
That’s how our bodies work most of the time. However, on rare occasions, that injury damages nerves in such a way that pain doesn’t ever subside; it becomes chronic. So why do some injuries fade away, while other people are forced to deal with chronic pain for months or years? Researchers say it’s due to nerve epigenetics.
As researchers from a recent study explain, think of epigenetics as a nerve’s “memory.” Just like traumatizing memories can stick with a person for years, so too can a traumatizing experience for a nerve. And just like a person, although you learn to heal and move on from the incident, certain actions can trigger that memory, and when it happens to a nerve, it can actively send off pain signals.
“We are ultimately trying to reveal why pain can turn into a chronic condition,” said Dr. Franziska Denk, an author of the recent study. “Cells have housekeeping systems….the majority of their content are replaced and renewed every few weeks and months. So why do crucial proteins keep being replaced by malfunctioning versions of themselves?”
For his study, Dr. Denk and his team examined pain signals in mice. They looked at some particular immune cells in the mice and found that when some nerves are damaged, their epigenetics change, and the epigentics remained in an altered state even after the nerve had “healed.” This change in epigenetics caused the nerves to become overly active, firing off pain signals during activity at at seemingly random times.
Dr. Denk’s team wants to conduct further studies to see if they can find a way to coax these damaged nerve cells into letting go or forgetting these traumatic experiences that are causing them to flare up when no pain is actually being experienced. They believe that by doing so, they could help treat millions of people who deal with chronic pain, and they could help stop the current opioid crisis in America.