A team of scientists has developed a new method for treating pain caused by nerve damage. The technique uses a specific chemical to block pain without interfering with other sensations and chemical signals. So far, the treatment is still in the early testing stages but shows promise. The details are in a paper that was just published in the journal Nature Neuroscience.
Nerve injuries and other types of nerve pain make patients recoil at the slightest touch. Currently, the only available treatment is the use of anesthetics, which completely shut down all sensations and signals in the treated site. The main cause of nerve pain is a type of ion channel called Piezo2. Piezo2 acts as a sensor in the skin and is sensitive to even very light touches. The STOML3 protein manually controls the gates of the Piezo2 channel, increasing or decreasing sensitivity. After nerve damage, the Piezo2 channels tend to remain open and active, causing pain. If STOML3 activity could be stopped without interfering with other signals, sensitivity and pain could be toned down.
Researchers used a screening tool called EU OPENSCREEN to test 35,000 chemical compounds in order to find chemicals that reacted with STOML3 proteins. They finally found a compound called OB-1, which inhibited STOML3 and kept Piezo2 gates closed. When the team tested an OB-1 drug on mice, the drug eliminated pain sensitivity, including pain from nerve damage and diabetes. Piezo2 channels remained inactive until the medication began to wear off. The drug could simply be applied externally to the area with nerve damage. No side effects were found but the OB-1 drug is still in very early testing stages.
The team’s discovery of OB-1 and its effects on nerve pain could be used to treat pain from nerve injuries, diabetes, and similar problems. OB-1 inhibits the activity of a protein that opens skin sensitivity channels. By keeping these channels closed, pain can be eliminated without interfering with other sensations or signals. The team hopes that their findings will eventually be applied to human medicine.
Lewin et al. Small-molecule inhibition of STOML3 oligomerization reverses pathological mechanical hypersensitivity. Nature Neuroscience (2016).