November 30, 2016
Platypus venom could be used as a diabetes treatment
Researchers in Australia have uncovered that two of its most notable creatures, the platypus and echidna underwent incredible evolutionary transformations in their insulin regulation. The discovery could potentially give rise to a new treatment for diabetes.
The team found that a hormone produced in the digestive system of the platypus, regulating blood sugar levels, is also found in the venom of the platypus.The hormone, called glucagon-like peptide-1, or simply GLP-1, is produced by both humans and animals. The hormone acts by being secreted in the gut which in turn triggers an insulin release, maintaining the levels of blood glucose in the body.
The problem, according to the research published in Scientific reports, is that GLP-1 breaks down rapidly in humans.
When individuals suffering from type 2 diabetes have a stimulus release caused by GLP-1, it isn’t enough to ensure the appropriate levels of blood sugar. This means that medications need to extend this triggered release of insulin to main the balance
"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," said study co-author Professor Frank Grutzner from the University of Adelaide's School of Biological Sciences.
"We've found that GLP-1 is degraded in monotremes by a completely different mechanism. Further analysis of the genetics of monotremes reveals that there seems to be a kind of molecular warfare going on between the function of GLP-1, which is produced in the gut but surprisingly also in their venom," added Professor Grutzner.
Venom helps to combat love rivals
Male platypuses fight each other for females during the breeding period, producing a venom containing GLP-1 as an aide to combat.
Echidnas also contain the GLP-1 hormone within their venom, however, they do not have the spurs on their hind limbs with which to deliver the venom.
"The lack of a spur on echidnas remains an evolutionary mystery, but the fact that both platypus and echidnas have evolved the same long-lasting form of the hormone GLP-1 is in itself a very exciting finding," explained Professor Grutzner.
"We've discovered conflicting functions of GLP-1 in the platypus: in the gut as a regulator of blood glucose, and in venom to fend off other platypus males during breeding season. This tug of war between the different functions has resulted in dramatic changes in the GLP-1 system," said Associate Professor Briony Forbes, of Flinders University's School of Medicine and another co-author of the research.
"The function in venom has most likely triggered the evolution of a stable form of GLP-1 in monotremes. Excitingly, stable GLP-1 molecules are highly desirable as potential type 2 diabetes treatments," she added.
Professor Grutzner concluded: "This is an amazing example of how millions of years of evolution can shape molecules and optimize their function.
"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."
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