Researchers at the University of Connecticut have developed a promising treatment that not only extends the lifespan of mice, but also improves their physical function throughout their lives. The study tracked health parameters such as grip strength and walking speed from old age until death, showing that treated mice were healthier and less frail than untreated mice in their final days. The results suggest that it may be possible to extend the lifespan of healthy humans by up to 10 years.
Monthly treatment can not only extend the lifespan of mice, but also help them maintain good health and vitality into old age.
Researchers have found that eliminating certain cells that cause inflammation in mice each month, starting in their 50s, not only extended their lifespan, but also improved their heart health and overall physical function throughout their lives. This approach shows promise for extending the period of good health in aging mice, which could pave the way for new treatments for aging in humans.
Everyone wants to live to a ripe old age, but no one wants to be decrepit. Researchers at the University of Connecticut have developed a treatment that could extend life—and vigor—until the end.
Although human life expectancy has increased over the past century, most older people suffer a severe decline in health in the last decade of their lives. Chronic diseases such as cancer, diabetes, or cardiovascular disease can set in, followed by frailty. Many interventions can prolong life, but not necessarily good health. And no one wants to spend the last years of an extra-long life in decrepitude.
But this fragile decline may not be inevitable. In the August 6 issue of Cellular metabolismMing Xu, a gerontologist at UConn School of Medicine, describes how a group of mice lived 9 percent longer when given monthly treatments, or about 79 extra days of life. But what’s striking is that not only did the mice live longer, they were able to walk faster and grasp objects with more force than untreated mice of the same age. In humans, slower walking speed and weakened grip are closely linked to increased overall frailty. The treated mice maintained their strength and walking speed throughout the treatment period until the end of their lives.
Detailed research methodology
This research is particularly important because of the careful measurement and record-keeping that this project required. Most experiments on mice, health, and longevity choose a certain endpoint in time (18 or 24 months) and measure the effect of treatment at that specific endpoint. But Xu, along with postdoctoral fellows Binsheng Wang and Lichao Wang and their colleagues, measured health, grip strength, and walking speed, along with a host of other parameters, on the mice every month from the time they were 20 months old (the equivalent of a 60-year-old human) until they died.
Some mice lived up to 43 months. This approach made it possible to assess each mouse’s physical function and overall health throughout the treatment period. Because each mouse died at a different age, this approach also allows Xu’s team to assess health in the period before death, which is often the most fragile and sickest stage of life.
Interestingly, they found that although the treated mice were older at the time of death, their physical function and overall frailty were better than controls during their final stage of life.
“We are all very excited about this discovery because it demonstrates that we are extending not only lifespan but also healthy life in mice, which is a key goal in the field of aging,” said Xu, an assistant professor in the UConn Center on Aging and the Department of Genetics and Genome Sciences at the UConn School of Medicine.
The researchers used two groups of mice. One group received monthly treatments to eliminate highly inflammatory cells from their tissues; the control group did not. “Highly inflammatory cells” were defined as those actively expressing a specific gene called p21.
The team, which included researchers from UConn Health, the University of Texas at Cedars-Sinai, the Jackson Laboratory for Genomic Medicine and the UNMC College of Dentistry, found that the monthly treatments extended both the mice’s maximum lifespan (the oldest treated mice lived to 43 months, or about 130 human years) as well as the average lifespan, so that the average treated mouse lived longer and healthier than the average untreated mouse.
The researchers are now working on a method to translate their results to humans. If the treatment works as well in humans, it could allow people to live an additional 8 to 10 years of healthy old age.
This research was primarily funded by the NIH National Institute on Aging, the American Federation for Aging Research (AFAR), and the Evolution Foundation.
