James Cook University scientists have found stonefish toxins could be used to fight parasitic worm infections suffered by nearly a quarter of the world's population.
JCU PhD candidate Danica Lennox-Bulow led the study. She said parasitic gastrointestinal worms (helminths) are a massive problem around the globe - and it looks to be getting worse.
"It's estimated that over two billion people, or a little over 24% of the global population, are currently infected with helminths. They can cause intestinal issues, organ damage, skin conditions, malnutrition and impaired growth and physical development," said Ms Lennox-Bulow.
To make matters worse, existing drugs are becoming increasingly ineffective against the worms.
"It's well-established that resistance has developed against all major classes of drugs used against helminth species that infect livestock.
"Within the last decade, cases of drug resistance have also emerged for helminth species that infect pets and humans. As such, new drugs with novel mechanisms of action are urgently needed," said Ms Lennox-Bulow.
She said the scientists decided to test stonefish toxins because of an interesting phenomena.
"Stonefish live on the seabed and don't have scales. As such, we would expect these animals to harbour a lot of parasites – but interestingly, they don't. One theory is that their ichthyocrinotoxins – toxins they secrete on their skin – afford them some protection against parasites," said Ms Lennox-Bulow.
The scientists tested skin toxins from Queensland's Estuarine Stonefish and Reef Stonefish against the infective (skin burrowing) larval stage of the Rodent Hookworm.
"While skin toxins from both stonefish species were found to be toxic to rodent hookworm larvae, those from the Estuarine Stonefish displayed the most favourable characteristics for therapeutic application.
"Specifically, the small size of the active components and their limited toxicity to mammalian cells in vitro are highly encouraging," said Ms Lennox-Bulow.
She said components within the skin toxins from the Estuarine Stonefish show promise for therapeutic development.
"There's still a lot of work to do before stonefish skin toxins are as effective against parasites as established drugs are. We need to drill down to find exactly what the active components are and we need to test these against a wider range of parasite species and taxa. But we've definitely found something here worth a closer look."
Link to paper here.
Images of Ms Lennox-Bulow and stonefish here.
Stonefish are available for media to view at the JCU Eduquarium.
