- Chronic pain can limit the quality of life as it lasts for a prolonged period of time and usually occurs due to hypersensitivity.
- The underlying mechanism of pain has not been understood up until this study that highlights the significance of micoRNAs.
- A research team from Karolinska University has identified targets for drug therapy that could improve therapy for chronic pain.
Pain is set off in the nervous system and chronic nerve pain can affect the quality of life led by the patient. Chronic pain is believed to be caused due to the hypersensitivity to pain neurons
but a new study by a research team from Karolinska Institute has found that a different neuron may be associated. This neuron is known to be associated with the sensation of pleasant touch but it could signal pain when there is nerve damage. The study was published in the journal Nature Communications
and it highlights the importance of the neuron in the development of chronic pain.
is a common condition but current treatment only provides moderate efficacy. The development of better drugs by the pharmaceutical industry has been hampered by the absence of a well-defined mechanism behind chronic pain.
‘microRNAs play an important role in the mechanism of pain development making them potential targets of therapy’
The long held belief was that certain neurons were associated with sensory perception while certain others were associated with pain. In patients with chronic nerve pain, even a simple touch can cause intense pain, but the steps involved in this process have so long been unknown.
Regulation of Sensory Neurons by microRNA
A research team from Karolinska Institute has identified microRNAs that are involved in the regulation of sensory neurons that manage the sensation of touch. When the nerves are damaged, there is a reduction in the levels of the microRNAs with a resultant increase in ion channels associated with pain.
Karolinska Institute's Department of Medical Biochemistry and Biophysics's Dr. Patrik Ernfors said, that the nerves that were sensitive to touch, switched function and began to produce pain, which could be the basis of hypersensitivity to pain. The professor further stated that the regulation of microRNA could be the reason why people have different thresholds for pain.
is a drug that is used predominantly to arrest nerve pain even though the mechanism of action was not understood. This drug works on the neurons that are sensitive to touch and which block the increase in ion channel that are associated with the decrease in mRNA levels. The important aspect is that only 50% of the population
responds to this drug treatment.
Dr. Ernfors said that nerve pain was a complex condition with many underlying mechanisms. The current study showed that mRNA molecules were associated with the regulation of nearly 80% of the genes
that are important for nerve pain. These could be new targets for drug therapy against chronic nerve pain.
The study was conducted on mice and there are further tests that need to be carried out before they can be conducted on humans.
An understanding of the mechanism that is associated with chronic pain is essential to develop an effective method of treatment. The current method of drug treatment is aimed at targeting the ion channels and the receptors that are associated with pain; this has been proved otherwise by the current studies.
Chronic pain is a pain that lasts for longer than 12 weeks while acute pain is a sensation that is intense and is indicative of injury. Chronic pain is persistent and can last for many months.
Chronic pain could be caused due to an initial injury, like a sprain, or it could be due to an underlying disease condition. Though there could be no clear association. Patients who experience chronic pain often have a poor appetite, disturbed sleep, changes in mood along with extensive fatigue. It can often limit a person's movement with reduction in flexibility, stamina and strength. Most people find it difficult to carry out daily activities because of the chronic pain.
Gene Associated with Chronic Pain
Catechol O Methyl Transferase (COMT)
gene is associated with the level of pain perception that an individual feels. The current study has shown that the level of microRNA regulates the genes that are associated with pain. Therefore, these microRNAs could serve as a potential target for drug therapy to alleviate pain.
- Genetic contributions to pain: a review of findings in humans - (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667226/)
- Chronic Pain: Symptoms, Diagnosis, & Treatment - (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667226/)