How aging prompts kidney disease
By Amy Ettinger
Millions of older cats are affected by chronic kidney disease. The disease is costly, affects quality of life and has few treatment options. In addition, the disease is often not diagnosed until the late stages, once 75 percent of kidney function is already lost.
Researchers at Colorado State University are investigating why kidney disease affects senior cats and are exploring the role of cell aging, known as cell senescence. With Morris Animal Foundation funding, the scientists are studying cells to determine whether cats with kidney disease have shortened telomeres, which are the specialized protective structures located at the ends of chromosomes. During normal cell division, telomeres gradually shorten and eventually become too short to protect the chromosome, which then signals the cell to stop dividing.
In humans, shortened telomeres and cell senescence have been associated with kidney disease and injury, says Dr. Jessica Quimby, a veterinary internal medicine specialist at Colorado State University who received a fellowship from the Foundation to study telomeres in cats. If a similar correlation were found in cats, it might help explain why the disease is so common in older cats.
During the study, researchers gathered cell samples from cats with kidney disease, older cats without kidney disease and healthy, young cats. The scientists are analyzing the cells to see whether cats with kidney disease show signs of shortened telomeres and cell senescence. If so, the findings may lead to the development of drugs that could turn back some of the signs of aging, Dr. Quimby says. But she adds that researchers studying telomeres need to be cautious and must fully understand the science because longer telomeres have been associated with such diseases as cancer, so potential treatments must strike a fine balance.
Dr. Quimby and a team of researchers are also investigating whether giving stem cells to cats can help fight chronic kidney disease. This project, which the Foundation is also supporting, is part of Colorado State’s feline stem-cell research project, the only one of its kind in the country.
The researchers isolated adult stem cells from the fat tissue of healthy, young cats and injected them into cats suffering from kidney disease. The team found that the stem cells potentially produce mild improvement in kidney function with minimal side effects. This could be an important key in managing kidney disease.
“Chronic kidney disease causes a lot of inflammation, which leads to scarring and kidney failure,” Dr. Quimby says. “Stem cells may help decrease the inflammation present and therefore slow down the scarring process.”
“Stem-cell therapy isn’t going to cure kidney disease, but it can potentially ameliorate it,” she adds.
Even without a cure, better treatments would certainly help keep aging cats with their families just a little bit longer.
Posted by MAFon December 8, 2011. Permalink