University of Queensland researchers have found seven peptides (mini-proteins) in spider venom that block the molecular pathway responsible for sending pain signals from nerves to the brain.
The discovery, published in the British Journal of Pharmacology, could inspire a new class of potent painkillers with fewer side effects than current medications.
The research team, led by Professor Glenn King from UQ’s Institute for Molecular Bioscience, said the seven peptides discovered in tarantula venoms blocked the human proteins known as voltage-gated sodium channels, which play a key role in pain transmission.
“Previous research shows people who lack Nav1.7 channels due to a naturally-occurring genetic mutation are unable to experience pain, so blocking this channel could potentially help us to switch off pain in people with normal pain pathways,” Professor King said.
“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.”
Dr Julie Kaae Klint, a former IMB postdoctoral researcher and current research associate at Evotec, said spider venom peptides had evolved to help spiders immobilise or kill their prey.
“A conservative estimate indicates that there are nine million spider-venom peptides contained within the venoms of the world’s 45,000 known spider species, and only 0.01% of this vast pharmacological landscape has been explored so far,” Dr Klint said.
Professor King said the team built a system 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.
“We analysed venom from 205 spider species and found that 40 per cent of the venoms contained at least one peptide that blocked human Nav1.7 channels,” he said.
“Importantly, of the seven promising peptides we identified, we discovered one that had the right structure, stability and potency to form the basis of a future painkiller.
“Our next step is to continue exploring the clinical potential of these peptides – and the ones we are still yet to find – in the hope of developing better treatments for the one in five Australians living with persistent pain,” Professor King said.
Source: University of Queensland