By Tracy Brighten
Scientists have found that compounds in spider venom may provide the key to developing a new class of painkillers for chronic pain relief
The study, published in the British Journal of Pharmacology, reveals the potential for analgesics without the side effects that restrict the dosage and effectiveness of existing medications.
Chronic pain affects 15% of the adult population worldwide, causing prolonged suffering and reducing quality of life. The economic cost is significant, and in the U.S. it is estimated at $600 billion a year, exceeding the combined cost of cancer, diabetes and stroke.
People feel pain when the body sends electrical signals from the affected area to the brain via the nervous system. However, some people do not register pain and previous research has identified a genetic mutation that modulates this pain pathway in these people. Of the nine subtypes of voltage-gated sodium channels that regulate the electrical properties of cells, Nav1.7 sodium channels are critical to pain sensation.
This new study identifies subtype-selective Nav1.7 channel inhibitors that could lead to new drugs that block pain without blocking other sodium channels that have life-sustaining functions, such as heartbeat regulation.
On the basis that protein molecules in spider venom immobilise prey by blocking nerve activity through sodium channels, this study analyses venom to identify peptides that can block human Nav1.7 channels. With 45,000 species of spider, there could be nine million spider-venom peptides as yet unexplored in pharmaceutical research.
Led by Professor Glenn King, researchers from University of Queensland’s Institute for Molecular Bioscience in Australia, along with Professor Frank Bosmans from John Hopkins University’s Department of Physiology and Neuroscience in the U.S, developed a research method that could analyse compounds in spider venom.
Venom from 205 species was screened and 40% of spider venoms were found to contain at least one of the seven compounds identified as inhibiting human Nav1.7 channels.
This exciting spider venom discovery will allow the most promising compound to be developed in the laboratory, offering hope of a new painkiller for chronic pain relief.
First published on Science Nutshell Mar 8, 2015
Klint, J. K., Smith, J. J., Vetter, I., Rupasinghe, D. B., Er, S. Y., Senff, S., Herzig, V., Mobli, M., Lewis, R. J., Bosmans, F., King, G. F. (2015). Seven novel modulators of the analgesic target NaV1.7 uncovered using a high-throughput venom-based discovery approach. British Journal of Pharmacology. DOI: 10.1111/bph.13081
Wiley Press Release (2015, March). New analysis of spider venom reveals seven promising compounds with the potential to relieve chronic pain. Retrieved from: http://au.wiley.com/WileyCDA/PressRelease/pressReleaseId-116382.html
Image credit: Mikhail F. Bagaturov