In the fight against disease, new weapons can turn up in some unexpected places. In this case, researchers have found a potential treatment for type 2 diabetes in the gut and venom of the world's only egg-laying mammals, the platypus and echidna.

Glucagon-like peptide-1 (GLP-1) is a hormone released in the intestines of humans and animals that instructs the pancreas to release insulin as the body's glucose level increases. It naturally breaks down in a matter of minutes, which is not be enough time for it to be effective in diabetic patients. As a result, longer-lasting GLP-1 analogues are often administered in medication, and research continues to look into other ways to increase its effectiveness, through new molecules, pills or even yoghurt.

But according to new research from South Australian scientists at the University of Adelaide and Flinders University, in the platypus and echidna that hormone doesn't degrade anywhere near as fast as it does in humans.

"Our research team has discovered that monotremes – our iconic platypus and echidna – have evolved changes in the hormone GLP-1 that make it resistant to the rapid degradation normally seen in humans," says Frank Grutzner, co-lead author of the study. "We've found that GLP-1 is degraded in monotremes by a completely different mechanism."

The platypus and the echidna are the only living species of monotremes, a group of mammals that lay eggs. These creatures have been found to not just use GLP-1 to regulate glucose in the blood, but have also developed a secondary function for the hormone in their venom, which the males use during breeding season to fend off other suitors competing for female attention.

"The function in venom has most likely triggered the evolution of a stable form of GLP-1 in monotremes," says Briony Forbes, co-lead author of the study. "Excitingly, stable GLP-1 molecules are highly desirable as potential type 2 diabetes treatments."

"This is an amazing example of how millions of years of evolution can shape molecules and optimise their function," says Grutzner. "These findings have the potential to inform diabetes treatment, one of our greatest health challenges, although exactly how we can convert this finding into a treatment will need to be the subject of future research."

The research was published in the journal, Scientific Reports.