More than 100 million people worldwide suffer from chronic pain. Pain is considered chronic when it lasts for at least three months. Varying in intensity from mild to severe, it can profoundly impair the quality of life of those who suffer from it.
At the Pasteur Institute in Lille, Dr. Priscille Brodin's team is working on the fundamental mechanisms of analgesia in order to eventually find ways to relieve millions of people suffering from chronic pain, without resorting to drugs that cause undesirable effects such as morphine.
Analgesia: discovery of a new mechanism
Worldwide, 55 million people suffer from lower back pain. 31 million migraines et 16 million cases of osteoarthritisThousands more suffer from shingles, fibromyalgia, cancerous tumors, or sciatica. Understanding the fundamental mechanisms involved in chronic pain has been the subject of scientific research for several years at the Pasteur Institute in Lille. Our researchers are trying to help the millions of people whose daily lives are ruined by this chronic pain. This is achieved by initiating research on the bacterium responsible for Buruli ulcer, in collaboration with the team of Dr. Laurent Marsollier In Angers, researchers discovered a lipid secreted by the bacterium, mycolactone, which has analgesic properties. "It has been found that this lipid is responsible for the absence of pain in patients with Buruli ulcer, which causes enormous sores on the skin that are normally very painful." asserts the Dr. Priscille Brodin, research director at Inserm and team leader at the Lille Center for Infection and Immunity. Indeed, mycolactone acts on the angiotensin II receptor present on the primary sensory neuron. It then triggers a local release of cellular potassium, which prevents the transmission of the nerve signals responsible for pain to the brain. This discovery of a new mechanism involved in analgesia opens up promising prospects for people suffering from chronic pain.
Towards an effective pain relief treatment
Currently, there are many treatments to relieve pain, but they are imperfect because they are not without side effects or toxicity that limit their use, such as non-steroidal anti-inflammatory drugs. (NSAIDs)Paracetamol, used as a first-line treatment, is well-tolerated at recommended doses but highly toxic to the liver at slightly higher doses. Morphine and its derivatives, on the other hand, cause constipation and respiratory depression, in addition to addiction, tolerance, and withdrawal syndrome. Furthermore, some types of pain, particularly those originating from damage to the sensory neuron itself, known as neuropathic pain, are resistant to most available treatments. Therefore, there is a significant need in this understudied area of medicine.
The stakes of the research at the Pasteur Institute in Lille are therefore crucial: to develop a pain relief treatment that mimics the natural effects of mycolactone. Mycolactone has a long-lasting analgesic effect at very low doses. In fact, a single dose of mycolactone can reproduce the effect of 1,000 doses of morphine Researchers also believe that a painkiller acting like mycolactone would be less addictive than morphine. To achieve this ambitious goal, our researchers are working in conjunction with the Drug Discovery Center, the new drug discovery research unit led by the Professor Benoit DeprezTogether, they are searching a large library of molecules for those that behave like mycolactone: they must both successfully bind to specific receptors on cells (angiotensin II receptor 2) and then trigger the same signal sent to the brain to prevent pain. If a molecule meets these criteria, the researchers could design a new, more effective, and better-tolerated treatment prototype to combat chronic pain.
Did you know?
People suffering from chronic pain have an average of 14 medical consultations per year. They are also more frequently hospitalized and take more sick leave than the rest of the population.
Since 2004, the fight against pain has become a public health priority in France. Pain assessment and management are crucial as a quality criterion. The law concerning patients' rights and the quality of the healthcare system of March 4, 2002, also recognizes pain relief as a fundamental right of every person.
