The Dog Aging Project: A Personal Journey
For Pat Schultz, enrolling her German shepherd-poodle mix, Murphy, in the Dog Aging Project wasn’t just a scientific endeavor; it was deeply personal. At the time, her husband was battling Alzheimer’s, and she hoped that the research could contribute to a better understanding of aging in both dogs and humans.
Murphy, who is now 12, is part of a larger group—over 50,000 dogs involved in this project. Across the country, scientists analyze various data points like diet, exercise, and even perform brain scans on these dogs. Veterinary neurologist Stephanie McGrath highlights that dogs age more quickly than humans and share many aging-related diseases, making them valuable for research.
“We can gather a lot of insights that would take decades to obtain from human studies,” McGrath notes.
Understanding Aging Through Tests
Matt Kaeberlein, a biologist with years of experience in aging research, co-founded the Dog Aging Project in 2014. His realization—that current methods to slow aging in lab animals might work for dogs as well—led to this initiative. He points out that mammals exhibit similar biological aging processes.
Currently, treatments usually transition directly from mice trials to human ones, but many medications that work on mice don’t translate well to humans. Dogs serve as a bridge because they live in human environments and share behaviors, like exercising and eating similar foods.
Data from the Dog Aging Project is openly available for researchers worldwide, contributing to over 50 studies so far. Some findings suggest that dogs with canine companions have a lower incidence of diseases. Additionally, inactive dogs are six times more likely to suffer from cognitive decline.
In assessing both physical and mental fitness, dogs take part in tests, like trying to recall where treats are hidden. In a recent assessment, Murphy displayed signs of anxiety, which McGrath suggested could indicate early dementia.
Exploring Dog and Human Brains
When dogs in the study pass away, their brains are donated for examination. Dr. Dirk Keene, a neuropathologist studying Alzheimer’s, has his motivation rooted in personal experiences—seeing his mother suffer from the disease and observing similar decline in his dog, Spring, which he characterized as “doggy dementia.”
Keene recalls Spring’s confusion and disorientation. He emphasizes that dementia is complex; it’s not solely about memory loss. The confusion associated with dementia affects spatial awareness in both dogs and humans.
Interestingly, dog brains share structural similarities with human brains, including various lobes. Keene explains that dementia affects brain size and structure similarly in both species, with smaller, shrunken brains and enlarged cavities being common indicators.
Spring’s donated brain exhibited signs of beta amyloid plaques, a key marker for Alzheimer’s in people, Keene mentions.
Researching Lifespan Extension
This project not only aims to improve dogs’ quality of life as they age but also investigates methods to extend their lifespan. One drug, rapamycin, has shown promise in preliminary studies with mice, suggesting it may slow cognitive decline and increase lifespan by 60%. This has sparked interest among some researchers for potential human applications.
Julie Moreno, a molecular biologist, conducted a pilot study involving 12 dogs showing dementia signs. For example, Qbert, a 10-year-old dog, was given a placebo, while 13-year-old Monkey received rapamycin. Moreno later studied their brains and found that Monkey exhibited fewer inflammatory cells linked to dementia.
Two other dogs on rapamycin also showed similar results. “If it works in dogs and is safe, it might help humans,” Moreno concluded.
Future of Aging Research in Dogs
The Dog Aging Project is currently engaged in a more extensive clinical trial, partially funded by the National Institutes of Health, administering either rapamycin or a placebo to numerous dogs, including Murphy. Meanwhile, a biotech company, Loyal, founded in 2019, is exploring three other drugs designed for older dogs.
Celine Haliou, the founder, envisions a preventive medication much like statins for humans that could enhance dogs’ health. She hopes this could lead to an extra “healthier year of life” for pets.
One of Loyal’s medications is being tested on dogs over ten, and while the FDA has approved its safety, final trial results may take years to materialize.
There’s considerable investment in understanding longevity, especially in Silicon Valley. Loyal has secured over $250 million to advance its drugs, and Haliou believes that successful outcomes for dogs could open doors for human longevity research as well.
“I think starting with dogs is a quick way to understand the biology of human aging,” she remarked.
