Perhaps old dogs can’t learn new tricks, but Purdue research veterinarian David J. Waters thinks they can teach humans a thing or two. Like how to live longer, healthier, cancer-free lives. To find out, Waters gets out of the labora-
tory in the spring for what he calls the Old Grey Muzzle Tour, making cross-country house calls on North America’s oldest Rottweilers. He wants to figure out what makes senior canines tick for so many years—and how their longevity secrets can be applied to humanity.
Waters and his team at the Center for Exceptional Longevity Studies at the Gerald P. Murphy Cancer Foundation, based in West Lafayette, started studying dogs for aging research in 1999 and collected data on more than 800 Rottweilers in the U.S. and Canada. In the process, they came across a special group: 21 Rottweilers who were at least 13 years old, the equivalent of a century in human years. Waters then focused his study on this group because “Rotties,” just like humans, are highly prone to cancer. While most of them live to be 8 or 9 years old and die from the disease, those who make it to 13 either don’t have cancer or have at least one type (sometimes several) without suffering any worse than if it were athlete’s foot. One common denominator Waters and his team discovered through their physical exams of the dogs is a surprisingly low level of the stress-inducing hormone cortisol. (Most animals, including humans, produce more cortisol as they age, and the ensuing stress exacerbates a litany of harms, including tumor growth.) The researchers are keen to understand why the oldest dogs in the country stay young physiologically, and whether their masters can emulate the achievement.
There’s plenty of precedent for trying to extend human lives by studying dogs. Canine research helped pioneer the use of insulin for diabetics and blazed the path for anti-hormonal prostate cancer treatments. And our dog friends are certainly closer relatives than the creatures more commonly used in aging studies: worms, flies, and mice.
But Waters believes researchers often get stuck in the office and can benefit from doing their work in living rooms. To do this, he drives more than 3,000 miles and boards a few planes on the Old Grey Muzzle Tour. His effort has paid off. While most vets would be lucky to see two centenarian Rotties during their careers, Waters has so far studied more than 50, including 13-year-old Thunder of Staten Island, whose “fitness regimen” included regularly pounding down slices of Key lime and pumpkin pie; 14-year-old Envy of Canada, who could still run a backyard agility course; and 15-year-old Kyrie of Alaska, whose two best friends were goats.
Somehow, the pie-eating champion, the fitness nut, and the goat-lover all defied the odds to become the most senior of citizens. When his 50-day tour wraps up this month, Waters will be a little closer to understanding why. He believes the most creative scientists are playful with words, and he has gotten as far as naming the dogs’ youthful cortisol response “the adaptive secret.” He defined the term at a TedX talk last year: “Adaptive, meaning ‘advantageous to the organism’; secret, which comes from the Latin meaning ‘we don’t have any freaking idea how the dogs are doing this.’”
Illustration by Daniel Downey
This article appeared in the April 2014 issue.