Spider venom can prevent pain, too

In news which may cause arachnophobes around the world to breathe a collective sigh of relief, researchers have discovered that spider venom contains compounds which have the potential to block pain. Their study, published in the British Journal of Pharmacology, shows particular promise for the 15% of adults worldwide who suffer from persistent pain.

Chronic pain treatment in the USA alone is estimated to cost around $600 billion a year - greater than the combined economic cost of cancer, diabetes and stroke. Furthermore, the study authors noted that current analgesics have “limited efficacy and dose-limiting side effects”.

Led by Professor Glenn King from The University of Queensland’s (UQ) Institute for Molecular Bioscience (IMB), the research team sought a method to block the voltage-gated sodium channel Nav1.7, which plays a key role in pain transmission. Professor King explained, “Previous research shows indifference to pain among people who lack Nav1.7 channels due to a naturally occurring genetic mutation - so blocking these channels has the potential of turning off pain in people with normal pain pathways.”

The team turned their search towards spiders, many of which kill their prey with venoms that contain hundreds or even thousands of mini proteins called peptides. Professor King stated, “We have nine sodium channels in our bodies and our challenge is to find peptides that can distinguish between these channels and target only Nav1.7 - something current pain relief drugs can’t do but spider venom peptides most likely can.”

The team developed a high-throughput fluorescent-based assay that allowed them to rapidly analyse a huge number of venom peptides in order to search for those with the potential to block Nav1.7 channels. Venoms from over 200 species of spider were screened, revealing that 40% of the venoms contained at least one compound that blocked the channels - more than any other natural source, according to Professor King.

The team discovered seven promising peptides in tarantula venoms, one of which had “the right structure, stability and potency to form the basis of a future painkiller”, said Professor King. He added that the team’s next step is to “continue exploring the clinical potential of these peptides - and the ones we are still yet to find”