Venom of tiny fish could lead to new pain treatments

In the study, a team of global researchers analyzed those glands and found the toxins are a chemical mix of different opioid peptides that act like morphine or heroine. The researchers dealt with the problem by taking the fishes out of their tanks and dangling cotton swabs in front of the blennies until they bit it.

Animal venoms are known to provide researchers with clues on how to produce new pain medications and even substances that they can work with.

Compared to snakes, spiders and scorpions, venomous fish - of which there are some 2,500 species - are a neglected group when it comes to the study of toxins, which is a shame, say researchers, as they could open the door to therapies for a wide range of ailments.

The study authors developed a very detail study of the venom of fang blennies. The most pain I've ever been in other than the time I broke my back was from a stingray envenomation. Predators fear them. At first glance, you'd be forgiven for dismissing the tiny fang blenny as an easy meal ticket. It can also be used in case the benny was already caught and eater.

The venom of these fearless 1.5-three inch (four-seven centimetre) swimmers - which are popular tropical aquarium fish - numbs would-be predators, rather than causing them pain, said the report in the journal Current Biology.

In his initial research, Dr Casewell read fang blenny studies carried out in the 1970s, where larger, predatory fish were "introduced" to the fang blennies. "While the feeling of pain is not produced, opioids can produce sensations of extremely unpleasant nausea and dizziness", says Brian Fry.

There are five genera of fangblennies, but only one with venom. For instance, they could develop a more effective painkiller by using the opioid peptides present in the venom.

Specialists indicate that a small tropical fish known as fang blenny has a venomous bite. Casewell added that it appears as if evolution favored the little fang fish with large teeth and later by filling them with venom. He also thinks 15 to 20 species of fish have evolved to look like venomous fangblennies to protect themselves from predators.

Scientists from the Liverpool School of Tropical Medicine and the University of Queensland in Australia became interested in these small, brightly coloured fish because their pain-free bite was so unusual in the marine world. Unlike most venomous creatures, blennies don't use this venom for capturing prey - they use it to escape their predators by getting them high.

Fry said the fang blenny was an "excellent example" of why nature and unique habitats must be protected, particularly the Great Barrier Reef.

The team started their study with "no grand hypothesis, just basic wonderment" says Fry, but given the results they plan to continue the study by analyzing the composition of venoms from different blenny species.

  • Tracy Ferguson