AIDS Drug May Work Against Bat Disease
Protease inhibitors may help in the fight against a deadly disease that's killing millions of bats.
Drugs that are widely used to treat HIV/AIDS and hepatitis C could in future treat white nose syndrome in bats, new research suggests.
So far the deadly syndrome has killed 6 million bats in North America alone, so the findings, published in the Proceedings of the National Academy of Sciences, provide some hope that remaining bats can be saved.
The disease is named for the white fungus, Pseudogymnoascus destructans. It infects the skin of the muzzle, ears, and wings of hibernating bats.
The fungus is sinister because it penetrates the bodies of the resting bats. The resulting injuries wake the bats, which in their discomfort, begin moving in their caves and flying when they should be hibernating. Eventually, most victims succumb to emaciation, since they run down their body fat stores meant to last them through the hibernation.
The HIV drugs, called protease inhibitors, appear to knock out much of the fungus. The word "protease" refers to enzymes that can break down proteins and peptides, so inhibiting these damaging enzymes holds many benefits.
"This study suggests that proteases may help in infection and so addition of protease inhibitors could block degradation and invasion of bat tissues by the fungus," Brown University biologist and co-author Richard Bennett said in a press release.
Bennett and his team discovered an enzyme, called "Destructin-1," which is secreted by the white nose syndrome fungus. This protease, along with other components of the fungus, can attack collagen, a primary protein found in animal connective tissues.
Hopefully "Destructin-1" can be renamed "Destructible," because the scientists found that the common protease inhibitor chymostatin biochemically reduces the activity of the deadly fungal enzyme. As a result, the researchers saw a 77 percent reduction in collagen damage.
They are puzzled, though, why that figure wasn't 100 percent. Bennett and his colleagues strongly suspect that something else besides Destructin-1 in the fungus is damaging to collagen.
As he said, "There is more to discover."
Photo: A bat infected with white nose syndrome. Credit: Ryan von Linden/N.Y. Department of Environmental Conservation
Did you know April 17 is bat appreciation day? And why not? These flying mammals, though they look a bit scary to some people, are actually most welcome critters, for all of the good they do. Bats are terrific pollinators and seed-dispersers of hundreds of plant species, and they eat tons of insects -- enough to match their own body weight on a good night of foraging. So on this day, appreciate them we will! Let's have a look at some more of these winged wonders.
Most bats spend their days sleeping, in preparation for their nocturnal foraging. Their slumber may look upside-down to us, but to them it's totally the way you're supposed to do it.
Bats love, love, love insects, but they'll also eat fruits, flower nectar, vertebrates, and -- yes, indeed -- blood.
This female dwarf epauletted fruit bat is in a family way, at the moment. Pregnant bats usually carry just one child at a time. Once born, the moms will nurse the newbies until they're almost fully grown, as the little ones' wings need to be fully developed before they can hunt for food on their own.
Bat colonies roost together, and can do so in unspeakably large numbers -- in the millions, in some cases and caves.
And when they take wing at dusk, they do that together too, in huge swarms.
There are more than 1,200 species of bat, the vast percentage of them insectivores.
Bats have generally small teeth that will vary by species, but they're plenty well suited to tearing into bugs, fruit, or even skin if the bat is among the small group of species that dines on vertebrates such as frogs or birds.
Bats' wings are a lot thinner than those of birds, which helps them move fast, with incredible precision. Of course their thinness makes them fragile and susceptible to tearing. But if the tears aren't too large, they heal quickly.
Sadly, bats today are experiencing a health emergency that first came to light in 2006. In large numbers, they're being decimated by a condition called white-nose syndrome, a fungus that grows on the muzzles, ears, and wings and is fatal nearly 100 percent of the time. This northern long-eared bat in Illinois is affected by white-nose syndrome. While there has been some
into treatments, there is as yet no cure for the disease. Here's hoping one arrives soon, because we need bats!