Skin mucus of Indian frog can help fight flu

Posted April 19, 2017

A frog in south India excretes a mucus from its skin that could one day help people fight off certain types of flu viruses, according to researchers. Other antiviral medications attack different parts of the virus.

Jacob said, "In this paper we screened 32 peptides, and the surprise was that four out of 32 had activity against the virus".

"It's a natural innate immune mediator that all living organisms maintain", said Josh Jacob, who co-authored the study at Emory University, Georgia. "There's no collateral damage", he said. "You and I make host defense peptides ourselves". Jacob thinks it's a coincidence.

To protect themselves in a soup of potentially unsafe microbes, many plants and invertebrates - including frogs - coat themselves with "host defense peptides".

Scientists at Emory University named the beneficial element "urumin", which can be isolated, after the a sword with a flexible blade that snaps and bends like a whip, which comes from the same Indian province.

The initial groundwork was laid by researchers from the Rajiv Gandhi Center for Biotechnology in Kerala, India.

Frogs can't catch the flu, but they're susceptible to bacterial infections and other diseases.

Lead researcher Joshy Jacob points out that they tested just a handful of frogs, while important discoveries of such kind tend to require thousands of trials.

Some frog mucus contains antimicrobial peptides, which are immune system molecules that can neutralize bacteria, viruses, and fungi.

One of the more incredible aspects of this study is how easily this peptide was discovered. Finally, they vaccinated mice with urumin and found that it protected them from a lethal amount of the H1 flu virus, the same strain responsible for the 2009 pandemic.

This could have great value since the current anti-flu drugs attack other parts of the virus and are thus not as effective in their action.

But Jacob believes other frog compounds nearly certainly will, and he's testing them against other viruses too, included HIV, hepatitis viruses, Zika and Ebola.

"I don't think people thought that they work that way before", Chinchar said about the peptide. He and his colleagues administered the peptide to mice and then exposed them to H1 viruses. Most peptide-based drugs are delivered intravenously, and that's not practical for an everyday drug, which is what Jacob hopes to develop. "The flu virus most likely shares a common motif with whatever the peptide is targeted to".

One of the molecules, urumin, successfully killed several viral strains, as well as a number of harmful microbes.

This discovery, reported Tuesday in the journal Immunity, will face many hurdles before it can become an actual influenza treatment.

"This peptide works against all influenza viruses of the H1 hemagglutinin subtype because it binds specifically to a conserved piece in this protein", explained Jacob to Gizmodo. [The peptide] doesn't keep you from getting [the flu] again, but it kills the virus.