Animal lovers often say their pets are like people, and when it comes to health, in many ways, they’re right. Dogs get cancer, cats develop arthritis, and many pets suffer from obesity. 

Cardiologist resident Kursten Roderick presses an ultrasound wand against the shaved chest of a mild-mannered yellow lab. The dog’s name is Cooper. He’s ten-years-old, and has active heart disease.

"With heart disease the pressure inside this chamber will increase and that chamber gets larger and larger The bigger it gets, the closer they are to heart failure."

Ruderick says Cooper can still go on his daily one-mile walks, but no hiking and no steep inclines, and she wants Cooper’s owner to watch his breathing. Cooper’s owner – and best friend – Chuck Duby took him to the Foster Hospital for Small Animals at Tufts to be treated.

"I never knew it was so similar to some of the human heart diseases, and to actually hear that he was on some human meds to treat the heart was kind of interesting," Duby said.

Cooper takes at least three medications that also are used to treat humans for similar conditions: Lasix, Enalapril, and Carvedilol.

But veterinarians at Tufts know that things can work the other way, too – that some pet medicine can prove useful to humans. Veterinarian Andrew Hoffman is the director of the Regenerative Medicine Laboratory at Tufts Hospital for Large Animals.

Hoffman said that just like with humans, there’s a lot of hope in stem cell therapy for animals.

"Stem cells are one of the pillars of regenerative medicine, so our lab is a stem cell laboratory," he said.

Hoffman’s lab studies how stem cells affect damaged cells and tissues in sick animals. Current clinical trials include studies on arthritis, chronic liver disease, autoimmune kidney failure, and the canine illnesses that resemble Crohn’s disease and multiple sclerosis. Even the heart condition that plagues Cooper, the yellow lab, is being investigated

"There is no human clinical trial, at least there wasn’t yesterday, applying stem cells to treat mitral valve disease, and that’s an area that we’re developing," Hoffman said. "This is a great opportunity to develop cell therapies in an area that’s received much less or little or no attention in human medicine."

All of the clinical trials in Hoffman’s lab involve vets and a human physician partner. This way positive results can be of dual benefit: to humans and pets.

"We pick the type of disease problems that have analogies to human conditions. They are not exactly the same, but they are very similar. And we explore novel therapies in those patients."

Using animals to better understand human diseases and to develop human medicines is nothing new. But most of the time, animals are specifically bred to be used for research. That sort of research is called an experimental model. For example, one experimental model at Tufts is the study of emphysema in sheep.

"This is entirely for human health. There is no veterinary analog to emphysema, there is no tobacco related illness, per se, that causes emphysema naturally in pets."

Sheep don’t smoke, and they don’t get emphysema, so to study that disease, doctors have to give it to the animal first. This gives researchers a high level of control, but it also means that the disease they are studying is genetically modified. Hoffman says that limitation is overcome by moving beyond lab animals and studying diseases that occur naturally in family pets.

"These are the patients that we see every single day with incurable diseases or diseases that are not treated satisfactory by standard of care," Hoffman said. 

These are the patients – the pets – whose outcome might be improved with new therapies. And if a pet’s outcome is improved, there’s hope that new therapies might help human patients, too. Veterinary oncologist David Vail has seen this happen. He said they've been doing this for approximately 10 years in an organized fashion. 

Vail is part of the Comparative Oncology Trials Consortium at the National Cancer Institute. The cancers that dogs and cats get are very similar to the cancers that people get, and studying those cancers in our pets can help speed up the process of getting new therapies to humans, he said.

"It’s a very expensive proposition. About a billion dollars and eight to ten years to bring a new anti cancer drug to market, so anything we can do to speed that process up is certainly helpful."

Vail said that pets have already done a lot for human health.

"Bone marrow transplant techniques were first developed in dogs with lymphoma," Vail said. 

So was a radiation therapy called TOMO, which is used to take images of a tumor while its being irradiated.

"That’s now currently available throughout the world, that unit, and the first patients to be treated on that unit were our veterinary patients here that had nasal cancer."

While humans may benefit, the purpose of treating diseases in pets is the same as treating diseases in people – to prolong life and good health. And in the process, perhaps bring new meaning to the phrase, “man’s best friend.”

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