Ever since last summer, when Lynn Gemmell’s dog, Bela, was inducted into the trial of a drug that has been shown to significantly lengthen the lives of laboratory mice, she has been the object of intense scrutiny among dog park regulars.
To those who insist that Bela, 8, has turned back into a puppy — “Look how fast she’s getting that ball!” — Ms. Gemmell has tried to turn a deaf ear. Bela, a Border collie-Australian shepherd mix, may have been given a placebo, for one thing.
The drug, rapamycin, which improved heart health and appeared to delay the onset of some diseases in older mice, may not work the same magic in dogs, for another. There is also a chance it could do more harm than good. “This is just to look for side effects, in dogs,” Ms. Gemmell told Bela’s many well-wishers.
Technically that is true. But the trial also represents a new frontier in testing a proposition for improving human health: Rather than only seeking treatments for the individual maladies that come with age, we might do better to target the biology that underlies aging itself.
While the diseases that now kill most people in developed nations — heart disease, stroke, Alzheimer’s, diabetes, cancer — have different immediate causes, age is the major risk factor for all of them. That means that even treatment breakthroughs in these areas, no matter how vital to individuals, would yield on average four or five more years of life, epidemiologists say, and some of them likely shadowed by illness.
A drug that slows aging, the logic goes, might instead serve to delay the onset of several major diseases at once. A handful of drugs tested by federally funded laboratories in recent years appear to extend the healthy lives of mice, with rapamycin and its derivatives, approved by the Food and Drug Administration for organ transplant patients and to treat some types of cancer, so far proving the most effective. In a 2014 study by the drug company Novartis, the drug appeared to bolster the immune system in older patients. And the early results in aging dogs suggest that rapamycin is helping them, too, said Matt Kaeberlein, a biology of aging researcher at the University of Washington who is running the study with a colleague, Daniel Promislow.
But scientists who champion the study of aging’s basic biology — they call it “geroscience” — say their field has received short shrift from the biomedical establishment. And it was not lost on the University of Washington researchers that exposing dog lovers to the idea that aging could be delayed might generate popular support in addition to new data.
“Many of us in the biology of aging field feel like it is underfunded relative to the potential impact on human health this could have,” said Dr. Kaeberlein, who helped pay for the study with funds he received from the university for turning down a competing job offer. “If the average pet owner sees there’s a way to significantly delay aging in their pet, maybe it will begin to impact policy decisions.”