Old Dogs, New Research and the Secrets of Aging

Dogs go through stages in their life, just as people do, as is obvious to anyone who has watched their stiff-legged, white-muzzled companion rouse themselves to go for one more walk.

Poets from Homer to Pablo Neruda have taken notice. As have folk singers and story tellers. Now science is taking a turn, in the hope that research on how dogs grow and age will help us understand how humans age. And, like the poets before them, scientists are finding parallels between the two species.

Their research so far shows that dogs are similar to us in important ways, like how they act during adolescence and old age, and what happens in their DNA as they get older. They may be what scientists call a “model” for human aging, a species that we can study to learn more about how we age and perhaps how to age better.

Most recently, researchers in Vienna have found that dogs’ personalities change over time. They seem to mellow in the same way that most humans do. The most intriguing part of this study is that like people, some dogs are just born old, which is to say, relatively steady and mature, the kind of pup that just seems ready for a Mr. Rogers cardigan. “That’s professor Spot, to you, thank you, and could we be a little neater when we pour kibble into my dish?”

However, teenage dogs don’t torment their actual mothers. They complain to their humans. That means a double whammy for some pet owners. If you happen to have adolescent human children as well as adolescent dogs and you all are stuck at home in close proximity because of a worldwide coronavirus pandemic, then all I can say is more research is required.

Perhaps I shouldn’t be flippant about these research projects. They involve some groundbreaking work and could have potentially important conclusions. Take that paper with the natural algorithms, for example. To come to those conclusions researchers sought patterns of chemical changes in DNA, a process called methylation that doesn’t alter the content of genes, but does change how active they are.

Lab tests can tell how old a human is just from the pattern of methylation. Thanks to this research, the same can be done for dogs. The results will help researchers studying aging in dogs to translate findings to humans. None of this research was done on dogs kept in a laboratory. All of the dogs in the aging comparison study were pet Labrador retrievers and the owners gave permission for blood samples.

Scientists are unsure about whether the physical decline seen in aging in dogs and humans, in fact in all mammals, is related to the process of development in earlier life, or whether the decline is a different process altogether. The researchers found that the pattern of methylation suggested that the same genes may be involved in both processes.

Elinor Karlsson at the Broad Institute described her research in genomics and dogs:
“One of the things that we’re really interested in is figuring out, first of all, whether there are things in the DNA of dogs that you can find that actually explain why some of them live a remarkably long time.” Those findings might be of use in extending healthy aging in people.

The study on the changes in dog personality over time used Border collies that were part of the Clever Dog Project at the University of Vienna. The Border collies were all companions, volunteered by their human owners. Humans are said to grow more easygoing, stable and agreeable as they age. We can all think of exceptions, probably in our own family, but overall statistics cannot predict the behavior of outliers like Uncle Rasputin or Aunt Ratchet.

How do you test dog personality? The Border collies were put through many different tests. In one, a stranger walks into a room and pets the dog. In another, the owners dress up their dogs in human T-shirts. One-fifth of the dog owners admitted to having done this before, on their own, not for research purposes. In another test, the owners dangle a sausage in front of their dogs just out of reach for a minute or so. Be assured this was approved by an ethics board, and the dogs were fed the sausages once the time was up.

The researchers found that dogs do change as they grow older just as people do. They become less active and less anxious. But one of the authors of the study, Borbalu Turcsan, of Eötvös Loránd University in Budapest, noted that some dogs don’t change as much over time. “People with more mature personality profiles change less as they age,” she said. “And we found exactly the same in the case of dogs.”

The end of aging is of course the same in dog and human. Dogs just get there more quickly. This is one thing that makes the dog a “good model for human aging and mortality,” as Dr. Promislow wrote.

“Dogs age a lot faster than people do,” Dr. Karlsson of the Broad Institute explained. “And so if you want to study aging with the idea that you want to help people within our life span, then you want to be able to study something that’s aging much faster than us. You can learn about it more quickly than waiting eighty years until somebody dies.”

Source link Health

Be the first to comment

Leave a Reply

Your email address will not be published.