When UCLA Medical Center cardiologist Barbara Natterson-Horowitz was asked one day to perform echocardiography on the failing heart of a Los Angeles Zoo emperor tamarin, a small monkey that evolved in the treetops of the Central and South American rainforests, she couldn’t have predicted how profoundly that act would change her thinking on human health. It was after making eye contact with the kitten-sized animal — and being chastised by colleagues for it — that she began to see a connection between the health of humans and “our nonhuman brethren.”
Last year, Natterson-Horowitz co-authored a book with science journalist Kathryn Bowers on the subject titled Zoobiquity: The Astonishing Connection Between Human and Animal Health. So when I heard the news this morning that researchers are now studying grizzly bears in the state of Washington for insights on human obesity, I wasn’t surprised. I wrote about the One Health Initiative concept in 2011.
Two years ago, comments on that article mentioned that it was an “interesting” and “enticing” idea, but one that was “way ahead of its time” at best and “impractical” at worst. However, the current grizzly bear study suggests it may be time to revisit the question: Should human and veterinary doctors be partnering, along with wildlife biologists? Could this lead to more human cures?
Disease doesn’t discriminate
According to Natterson-Horowitz, jaguars get breast cancer. Rhinos in zoos get leukemia. Chimpanzees in the wild experience depression and sometimes die from it. Melanoma has been diagnosed in the bodies of buffaloes. Western lowland gorillas die from a terrifying condition in which the aorta ruptures, and dinosaurs got brain tumors. It turns out that nonhuman and human animals have a lot of health issues in common.
When it comes to obesity and diabetes, two of the most pressing human health concerns of our time, there is a strong connection, as well. And researchers are now studying grizzly bears to, hopefully, design remedies for people.
Dr. Kevin Corbit, a scientist at the California-based drugmaker Amgen, Inc., is conducting research on captive grizzly bears in labs at Washington State University. The bears in the center there, set up almost thirty years ago, are either born at the facility or rescued from places such as Yellowstone National Park because they got too close to humans and would otherwise have been euthanized.
Hibernating bears are experts at naturally gaining weight. In the weeks before hibernating, grizzlies pack away enough salmon, apples, and berries to put on one hundred pounds or more. Their bad cholesterol jumps and their blood pressure spikes; but unlike with humans, their health doesn’t deteriorate. The bears’ arteries don’t clog from overeating, nor do the animals suffer from heart attacks or turn into diabetics. It seems the bears have figured out how to be healthily obese and then lose massive amounts of weight without problems.
Dr. Corbit has stated that his studies of the bears’ fat and blood samples suggest that they are able to adjust their sensitivity to the insulin hormone that controls how much the fat and sugars in food are broken down and stored for energy. The bears are more sensitive to insulin while putting on the pounds. When hibernating a few weeks later, they shut off their insulin responsiveness entirely. Over the next two years of the project, Dr. Corbit plans to explore how they succeed in doing that — eventually with help from sequencing the bears’ genome.
The doctor will see you now
While news of the grizzly bear study does bring up other questions about the complex and important ethical issues of lab-animal investigation, it is known that wild animals in forests, jungles, and oceans sometimes get sick and acquire diseases, just as we do. Perhaps we could improve the health of all species by learning more about how animals live, get sick, heal, and die in their natural settings.
Today, most physicians will go through their entire careers never professionally interacting with veterinarians. But a century ago, they did. In many communities back then, animals and humans were cared for by the same practitioner, the town doctor.
To tell you the truth, I wouldn’t mind if my doctor routinely cooperated with animal experts. I think it would be cool if someday I went to my physician’s office and sitting in the waiting room beside me was a poodle — or a pachyderm.
Do you think that human doctors, veterinarians, and wildlife biologists should be educated cooperatively and work in the same facilities to improve health care for human and nonhuman animals alike?
Here’s to finding your true places and natural habitats,