A toxin present in scorpion venom stimulates the pain system through a mechanism hitherto unknown to scientists. A property that could be used to design new treatments for chronic pain.
The habit does not make the monk ... Despite its dangers, the scorpion could help us get back to health. According to researchers at the University of San Francisco and the University of Queensland, a toxin found in the venom of Australian rock scorpion Black rock could help in researching the circuits of pain in the human body.
The wasabi receiver
The researchers made this discovery while conducting a study on different venoms and their action on the TRPA1 receptor. The latter is nicknamed the wasabi receptor because it activates when it detects a potentially harmful element for the body, such as wasabi. It reacts particularly to reactive electrophiles such as cigarette smoke or pollutants. "He is active to warn you that you are exposed to something dangerous that you have to move away from," said John Lin King, one of the authors of the research.
Understanding the action of venom on the pain circuit
Scientists have isolated WaTx protein from scorpion venom. They found that it activates the TRPA1 receptor differently than other compounds. Normally, these are ingested by the cell via a complex process or pass through protein chains to access the inside of the cell. WaTx manages to pass directly through the cell membrane. "It's unusual for a peptide toxin," the researcher wonders, "but at the same time, it's very exciting because if you understand how it goes through the membrane, you can use it to bring things to life. inside cells, like drugs, that can not normally go beyond the cell membrane. "
Venom does not cause inflammation
The protein of the scorpion venom has another specificity. All compounds that can trigger a reaction of the wasabi receptor act in the same way: once they are hooked to the receptor, they modify the chemistry of the allosteric node, the TRPA1 chain is modified, sodium and calcium ions can now enter the cell. This process causes pain. As calcium enters in larger amounts, inflammation then appears. With scorpion venom protein, the chemistry of the allosteric node is not modified in the same way and the sodium ions are present in larger amounts. Venom causes pain but no inflammation. "These results suggest that we could separate pain from inflammation," adds the researcher. According to him, the findings on TRPA1 could lead to the development of new non-opioid analgesics.