The mystery of aging

WEST LAFAYETTE, IND. — Old dogs may be able to teach veterinary researchers new tricks about cancer and aging.

David J. Waters, DVM, PhD, associate director of Purdue's Center on Aging and the Life Course and comparative oncology professor in the Department of Veterinary Clinical Sciences recently completed a 23-day tour of 16 cities to gather information about the nation's oldest Rottweilers. Rottweilers frequently succumb to cancer by age 8 or 9, and Waters says all the dogs he visited were far beyond that milestone, with most considered the centenarians of the dog world.

Over the last three years, Waters' team at the Center on Aging created a database of more than 140 Rottweilers with exceptional longevity, but only 15 remain today. So he decided now was the time to get up close and personal and discover what it is about these dogs that have allowed them to have such longevity.

"If you're looking to come up with new theories on how kids can learn better, then you better carefully observe kids learning. When it comes to developing fresh insights on what it takes to age more successfully, the same holds true. There's no substitute for careful firsthand observations," Waters says. "Our working hypothesis is ... that each dog is uniquely different and this uniqueness holds the key to better understanding the different pathways to successful aging."

Questionnaires completed by the dogs' owners prior to the study, dubbed "The Old Grey Muzzle Tour," asked for information about their medical histories, diet and dietary supplement usage, and parents' longevity. The tour was completed under the work of the Center for Exceptional Longevity Studies, Gerald P. Murphy Cancer Foundation, where Waters serves as director. At each stop on his fact-finding tour, Waters collected DNA samples, measured each dog's height and chest/belly circumference, and performed physical examinations. He observed the dogs in their home environment, paying close attention to how the dog was regarded by the household.

"For centuries, dogs have enriched people's lives in important ways as our pets and our companions," Waters says. "Now we are recognizing that a special group of dogs may have something important to tell us about successful aging. This tour sends a simple message: We're prepared to listen."

One of his most notable stops came in Riverside, Iowa, where Waters met Two Lane, a female Rottweiler aged 14 years and 3 months — the equivalent of a 109-year-old woman. The robust Rottweiler, ironically, lived just down the highway from the oldest living person at the time, Neva Morris, age 114.

"We think exceptional longevity is more than just superb genetics," Waters says. "What an interesting tale about these two old girls living in the heartland."

It's too early to draw conclusions about what he learned during his trek, but Waters says he is eager to further dissect the information he collected. Cancer resistance most impressed him at first glance, he says, adding that 14 out of the 15 Rottweilers had never received any cancer diagnosis. Cancer most frequently appears in older tissues, so Waters says this revelation has important implications for both cancer and aging research.

"Like people, Rottweilers and prone to cancer and we think the freshest ideas in cancer prevention will come from studies in aging," Waters says. "That's one of the things we're doing. We're training the next generation of scientists who will be cross-trained in aging and cancer."

Additionally, his research will add to a new trend toward "healthspan," as a way to promote quality of life.

"Cancer resistance is only one of the keys to successful aging. Our research is all about gathering clues from pet dogs, not just cancer."

For more information go to www.gpmcf.org to learn more about the Old Grey Muzzle Tour.