Our Bodies “Remember” Pain, New Pain Research Says

Pain is an important part of all of our lives. It lets us know when we are injured or have a problem that need to be addressed. However, pain can become an issue when it stops being acute and evolves into a more chronic condition after the cause has been resolved. It is believed that psychological effects play a large role in the development of chronic pain. There are numerous new pain research studies that dive into the mechanisms behind pain. These try to identify the underlying causes to eventually create powerful new treatments for those who suffer from chronic pain.

Four new pain research studies

1. The body “remembers” pain, new pain research says

New research from King’s College London explores how even mild injuries can leave a molecular “footprint” or marker on DNA. The researchers examined the immune cells in the nervous system of mice to better understand why some have an overly sensitive system that responds much more than it normally should. It is believed that certain markers can exacerbate pain and lead to lasting damage and chronic pain even after the injury has subsided.

The study found that nerve damage changes the epigenetic marks on some of the genes associated with these immune cells. Epigenetics refers to the numerous chemical compounds in the body that can attach to DNA and direct it to take certain actions such as turning genes on and off as well as controlling the production of proteins. The study demonstrated that immune cells still act normally, but the presence of these unique epigenetic marks may mean that the cells carry the memory of the initial injury.

This study is one of the first of its kind in this arena, however, it is believed to be an important step forward. The discovery of this novel marker will lead to new research. It may also help answer the question if this epigenetic marker is the real reason chronic pain persists in patients in the long-term.

2. Drugs for mood disorders may help combat chronic pain

A team from the University College London has developed a group of drugs for mood disorders that shows promising results in also being able to combat chronic pain. In previous studies, people who were identified to have certain variants of the protein FKBP51 were observed to feel greater physical pain after a trauma. This research focused on mice who lacked the protein FKBP51, which is an important protein in regulating stress levels.

This pain research study demonstrated how this protein shapes the body’s response to stress and amplifies pain, leading to a chronic pain condition. Inhibiting this protein was shown to have a powerful effect on the chronic pain in mice by alleviating the pain without numbing the entire pain response throughout the body. This new discovery opens avenues for future research and pain treatments in the future.

Senior author Dr. Sandrine Géranton describes the new drug by stating:

“The compound was designed to have positive effects on mental health, but we have discovered that it also has significant benefits for physical pain syndromes. Who wouldn’t want a treatment that relieves chronic pain while also making you less stressed?”

3. Researchers discover source of allodynia

Pain can take many forms, including allodynia: the pain that is magnified by sensations such as touch, light, or heat. It is believed that the spinal cord and glial cells play a major role in allodynia since they are the most abundant in the central nervous system, however, the exact underlying mechanism remained a mystery.

A group of researchers at the National Institute for Physiological Science has shed some light on this mystery. They discovered unique effects in the S1 cortex of the brain pertaining to sustained allodynia in the body. This remote region of the brain is not directly affected by spinal cord injuries, but manipulating the S1 cortex has been shown to relieve neuropathic pain in various animals and people.

This could be the first step to developing new pain treatments that focus on manipulating this region of the brain to suppress neuropathic pain in humans. Author Sun Kwang Kim explains that relief from direct manipulation of the S1 cortex could have serious implications on the region’s purpose.

“This suggests the S1 cortex might act as a sort of central processing unit within the brain networks that mediate and/or sustain chronic neuropathic pain. We hypothesized that S1 astrocytes, a type of glial cell, may show functional changes following peripheral nerve injury, resulting in mechanical allodynia.”

4. Complex regional pain syndrome and the brain

Complex regional pain syndrome (CRPS) is a chronic pain condition that affects one of the limbs, such as the arms or feet. It usually occurs after an injury or trauma to that extremity. It is believed that this syndrome is caused due to damage to the central nervous system at the time of the injury and can spread to other parts of the body.

Aalto University scientists, in collaboration with scientists from Helsinki University Hospital and Harvard Medical School, have found a new connection between the choroid plexus of the brain and CRPS. The choroid plexus is the part of the brain that produces cerebrospinal fluid that cushions the brain’s cortex. It also controls what substances from the blood pass over into the cerebrospinal fluid, brain, and spinal cord.

This new pain research used magnetic resonance images of the brain to show that patients suffering from CRPS have a choroid plexus 21% larger than the average subject. This discovery suggests a heavy involvement of the choroid plexus in CRPS. It also offers an interesting target for future research that is trying to identify what parts of the brain play an important role in pain.

What new pain research have you heard about? Which research do you find most exciting?