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rapamycin: drug hopes to extend life expectancy of dogs

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Old senior Pug on couch | Rapamycin drug hopes to extend life expectancy of pets | Petplan
Posted by Dr. Ernie Ward on Nov 09 2015

Veterinarians search for ways to help pets enjoy longer and healthier lives their entire careers, driven by the desire to enable dogs and cats to remain vigorous and vital for many, many years. A drug, rapamycin, may also help dogs fight the effects of aging and prolong life in animals and humans.

How Rapamycin works

Rapamycin is most commonly used as an anti-rejection drug after kidney transplants. The compound was found in a soil bacterium on Easter Island, known to locals as Rapa Nui. During tests, scientists noted laboratory mice lived longer. Subsequent experiments validated rapamycin’s effect on extending the lifespan of mice. If it could help mice live longer, what about humans?

We’ve been down this road before. Resveratrol, the substance found in red wine, was touted so highly that the company that discovered it was bought for $720 million. It’s no longer in business. In fact, scientists have yet to concoct anything that’s been proven to slow, stop or reverse aging in humans.

The fountain of youth appears to be a combination of genetics and lifestyle habits. That’s why recent technological innovations and drugs such as rapamycin create such excitement. The big break could be in the next beaker.

Slowing aging in dogs

New scientific experiments and better understanding of how and why animals age offer renewed hope that we may actually be closing in on slowing aging. Researchers at the University of Washington in Seattle have begun a small pilot study evaluating the effects of rapamycin on dogs. As of October 2016, the scientists had completed a 10-week pilot study on 16 dogs.

Early results are promising; several dogs that received rapamycin reported improved heart function, increased energy and enhanced quality of life. While these encouraging results are very preliminary, the scientists are convinced enough to pursue longer and larger experiments on up to 150 dogs in 2017-2018.

One of the key questions we can’t answer yet is how does rapamycin extend the lifespan in mice? It appears to impact a protein involved in cell growth, but we don’t understand how that affects lifespan.

Perhaps rapamycin improves other aspects of health such as cardiac function or prevents cancer. The mice studies concluded that not only did mice live 9% to 14% longer, they had fewer diseases and were sick less. This is what scientists call “squaring the curve” or extending the quality of life rather than prolonging illness or impairment. Hopefully, newer research will begin to unravel how rapamycin works. That answer may lead to other breakthroughs in other beakers.

Rapamycin risks and benefits

Rapamycin doesn’t come without risks. Side effects reported include cancer, diabetes, serious infections and more.

The dosage used for dogs is considerably lower than the human dosage, giving hope that these side effects may be sidestepped. My hunch based on the current literature is rapamycin will at least improve heart function and systemic blood flow while simultaneously boosting immune function. In humans there’s hope rapamycin may slow cognitive decline. At this time, I’m remaining cautiously optimistic for a happy ending to the rapamycin story.

Rapamycin is one of a handful of drugs that hold promise in slowing aging. You can bet I’ll be closely monitoring these developments for my patients and readers. Until we have more information, the fountain of youth is in your hands.

Here's 5 tips to help your pet age their best:

1. Feed a healthy, wholesome diet with plenty of water.

2. Exercise at least 30 minutes a day.

3. Avoid high-sugar and calorie treats and try wholefood and fresh snacks.

4. Have your pet checked out every year by your veterinarian and don’t forget urine and blood tests to uncover hidden diseases.

5. Talk with your veterinarian about nutritional supplements that may benefit your dog or cat.