Bats are the only flying mammal.
But that's just one of a long list of bats' unique attributes, including an unusually long life and the ability to avoid the effects of aging. In Northeast Ohio, researchers searching for the fountain of youth by studying bats.
A bat sees with sound. It sends out high frequency chirps, and then listens for the faint echo of a leaf, a telephone wire or a tasty mosquito.
Echolocation, and the necessity of a fine set of ears, is what first drew NEOMED neurobiologist Alexander Galazyuk to study hearing in bats.
To his surprise he found that a bat's auditory system is very similar to ours, "but much sharper.”
Eventually Galazyuk got to wondering if bats, which can live for decades, experience age-related hearing loss like virtually all other mammals, including humans.
Galazyuk posed the question, "How can bats survive for so long if they’re also losing hearing?”
He decided to compare hearing in young and older bats, but he ran into a problem.
“We were collecting animals in the wild," Galazyuk says, "and we could not age them because we have no clue how old they are.”
Unlike humans whose gray hair, worn teeth, age spots, baldness, stiff joints and wrinkles provide abundant clues to age, he says, "all bats look like young ones when they are old.”
The Fountain Of Youth With Wings
Galazyuk’s lab is filled with equipment to measure sounds and brain waves.
There’s also a box that contains a pair of big brown bats, Eptesicus fuscus, a species still common in Ohio despite the ravages of white nose syndrome.
“They are as big as mice, but they live much longer life," says Galazyuk as he holds up a chittering specimen.
These bats live 20 years or more says Galazyuk, an unusually long time for such a small animal.
Another local species, the little brown bat, can live more than twice that long.
Stepping inside his lab's special soundproof research chamber, Galazyuk reveals his long-range plan.
“We are trying to introduce to the field an absolutely new, fantastic anti-aging model,” he says.
Does he believe bats hold clues to the Fountain of Youth?
“Yes, exactly,” Galazuk says.
Bats, he says, could hold the secrets for humans to someday avoid not only age-related hearing loss, but also the ravages of osteoporosis, arthritis, cellular damage and even cancer.
Secrets Behind Bendy Bones
NEOMED developmental biologist Lisa Noelle Cooper is helping with the research.
“Bats are excellent at preventing age-related declines in multiple systems,” she says.
Her focus is on the unique properties of bats' bones.
Cooper shows off a set of 2-inch long wisps of bone.
"These are the palm bones here, the metacarpals,” she says.
Holding one between her thumb and forefinger, she bends it nearly in half.
“So that’s been out of the body since 2014, and it’s still that compliant,” Cooper says.
Bats need bendy bones to fly, she says, and they need to maintain that bendiness throughout their life.
“Over time they aren’t getting fragile with age," Cooper says, "and they’re the only mammals we know so far that are taking that matrix and keeping it healthy.”
She says when bats hit middle age, a renewal cascade kicks in that replenishes the bendy component of the bone, a protein called collagen.
Cooper is gathering data on each step in that molecular pathway, “and we’re going to be mining that to look at what’s the regulator, what’s the main gene that turns on this whole cascade.”
She envisions a time when the secrets of bone renewal in bats is utilized to prevent deterioration in our bones.
She says it requires "figuring out what’s the right cocktail of genes in order to create this ability in people to be able to renew their collagen matrix and stop the mineral loss.”
Bats: The Best Longevity Model
Cooper has also figured out a way to solve Alexander Galazyuk’s original problem of determining how old a bat is.
She’s devised a test of metabolites in the bats’ feces that corresponds with age.
In the course of that work, Cooper also discovered that as they get older, bats produce increasing amounts of potent anti-tumor compounds.
“With age," she says, "the bats are synthesizing chemicals that allow for them to prevent aging in a variety of systems.”
Where all this work is leading, Cooper says, is that these winged marvels could become the workhorse of researchers seeking keys to keeping humans ever youthful.
“The whole idea is prevention," she says, "and bats are the best model for that they we’ve ever seen.”
