A molecule from the slime of a colorful Indian frog kills some flu strains and could provide a promising route for new treatments.
In a study published today in the journal Immunity, researchers caught the Indian frog Hydrophylax bahuvistara and collected their skin secretions after mildly electrocuting them. (Don’t worry, the animals were returned to their natural habitat.) They then isolated several molecules from the secretions and tested them on human blood cells until they found one, called urumin, that killed flu viruses while not hurting the cells. 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. We’re not quite at a frog slime vaccine yet, but it’s a first step toward a new way to fight the virus that doesn’t involve traditional antibiotics.
Frog mucus contains peptides, or short chains of amino acids. In today’s study, first scientists screened 32 frog peptides against various flu strains, and found that four of them could fight off the virus. But when the researchers put these peptides in a dish with human red blood cells, three of them killed the blood cells by punching holes in their cell membranes. So that’s out.
The fourth — urumin — was safe and killed flu viruses. (It’s named urumin after a whip-like Indian sword called the “urumi” which is from Kerala, the same region as the frog.) By using an electron microscope, the researchers saw that urumin completely destroyed the flu virus by binding to a specific protein found in many strains of flu. This makes it versatile, though not a cure-all: it didn’t work against a modern strain called H3N2.
Still, urumin could be promising when current drugs don’t work anymore. I, for one, am ready for my frog mucus treatment.