We all know that diabetes, whether in a person or a dog, can be treated—but what about treated with one injection that lasts for years rather than twice-daily insulin shots? Some exciting research out of Spain suggests it may be true, at least for our canine friends. The promise appears to lie in gene therapy.
Scientists at Barcelona’s Universitat Autonoma had amazing results with gene therapy used on mice with the disease. But mice are not dogs, which are much closer in their anatomy and biochemical makeup to humans.
The investigators, led by Dr. Fatima Bosch, injected five beagles with two viral vectors (“vehicles”) carrying two genes. These vehicles were able to “infect” cells in the dogs’ skeletal muscle, leading to the expression of both genes. Skeletal muscle is key because its cells do not divide, meaning that the genes can remain there for a long time and keep doing their work.
In this case, their work was to sense the presence of glucose, or blood sugar, and keep regulating glucose levels so they didn’t go too high — the hallmark of diabetes that leads to all kinds of complications, including nerve damage, amputations, and heart and kidney disease.
After four-plus years, the single shot continued to do the trick, keeping blood glucose within a tight range — not too high, and not too low, which has not been the case with other experimental treatments for diabetes.
More recently, in a follow-up study, it was found that two of the dogs originally studied had normal glucose levels in their blood after eight years, exhibiting even further promise for this kind of therapy.
The injection cannot be considered a cure because it does not resolve the underlying reason for the body’s inability to produce the insulin necessary to keep blood glucose within the proper range. But it certainly provides a possibility for making treatment infinitely easier. As those who have dogs with diabetes know, making sure their pets get an insulin shot every 12 hours, pretty much to the hour, is not a small feat.
If further research continues to confirm and refine the findings, gene therapy research on people with diabetes will be in the offing. But there is an important difference between diabetes in humans and our canine friends in the study. Insulin is produced in the pancreas, and in the dogs tested, the destruction of pancreatic cells was chemically induced. In human diabetes (we’re talking type 1 diabetes here), pancreatic cells are done away with by the body’s own immune system. Still, we’re getting closer.