Some deadly and paralytic neurotoxins usually associated with snake venoms will no longer require animal testing.
Research conducted by University of Queensland (UQ) scientists and others has discovered an animal-free technique for testing toxins that will not demand euthanasia of its subjects.
The research is contained in a paper published in the open-access MDPI journal Toxins on October 16.
Test animals die slowly
A 2003 research paper published in ResearchGate journal Toxicon (Animal experimentation in snake venom research and in vitro alternative) cited the following description of how lab animals are used to test neurotoxic venom: "neurotoxic activity is usually assayed by inoculating mice intravenously or intraperitoneally and registering the mortality rate due to asphyxia following paralysis of respiratory muscles".
The Toxicon paper acknowledged society's opposition to animal experimentation: "Stringent regulations governing the use of animals, limited research funds and public pressure all focus the need for progress towards non-animal, or non-sentient, research methods."
Snake-venom research is conducted for various reasons, but mainly to develop antivenoms for use in treating humans bitten by venomous snakes and to discover new medicines for use in a wide range of human diseases and chronic conditions, including heart disease, arthritis, and painkillers.
A 2013 paper published in the Indian Journal of Medical Research estimated that 46,000 cases of human fatal snakebite occurred in India alone in 2005.
UQ associate professor Bryan Fry, who works in the Australian university's Venom Evolution Lab, told SCITechDaily on October 29 that the old method of obtaining animal tissue for analysis was accurate but slow and necessitated the death of the animal test subjects.
“Our new method uses optical probes dipped into a solution containing the venoms and we measure the binding to these probes—the critical factor—by analyzing changes in the light reflected back. It’s going to reduce the numbers of animals used for research testing, but it also has significant biomedical implications," Fry said.
“The team can now—without the use of animal subjects—screen venoms for non-target activities that may be relevant for drug design and development, helping treat all types of ailments. For example, we’ve shown that temple pit viper venom has an unusual cross-reactivity for the human alpha-5 receptor, which is a major target for conditions including colitis and smoking.
“Who knows what other potential treatments the world’s venoms could lead to? We’re excited to find out.”
U.S. labs alone kill 100 million mice and rats annually
No estimate was given for how many animals' lives may be spared as a result of the discovery; domestic chickens and mice are two of the animals frequently used in such testing.
U.S.-based animal-rights organization People for the Ethical Treatment of Animals (PETA) estimates that 100 million mice and rats are killed every year in U.S. labs alone.
In the paper's abstract, published in Toxins, the authors summed up their discovery's possible applications: "We have shown that our novel method is broadly applicable for studies including evolutionary patterns of venom diversification, predicting potential neurotoxic effects in human envenomed patients, and searches for novel ligands of interest for laboratory tools and in drug design and development."
The authors also stated that their research would be "of major interest for drug design and development".