New research from Israel suggesting that exercise enables you to age more gracefully may also lead to a drug to increase muscle mass and to reduce the effects of aging.
The latest research from Israel suggests that the key to aging gracefully may lie in our own hands. Or at least in our own muscles. The secret to staving off the loss of muscle mass that accompanies aging may lie in endurance exercise, like spinning or jogging. Both activities increase the number of muscle stem cells and enhance their ability to rejuvenate old muscles.
Prof. Dafna Benayahu of Tel Aviv University’s Sackler School of Medicine hopes that her finding will lead to a new drug to heal muscles faster. “With this advance, we can dream about creating a drug for humans that could increase muscle mass and ameliorate the negative effects of aging,” as well as help the elderly and immobilized to heal their muscles faster, she says.
The real rat race
Benayahu and her team say their findings explain for the first time why older people who have exercised throughout their lives age more gracefully. The results of the study were recently published in the journal PLoS ONE.
The muscles and skeleton in our bodies work together, explains Benayahu. “When we age, we experience sarcopenia, a decline in mass and function of muscles, and osteopenia refers to bone loss,” she says. As a result, our musculoskeletal system is more susceptible to daily wear and tear, which also explains the increased risk of falling in the elderly.
Investigating a rat population, Dr. Gabi Shefer from the research team says that the finding shows that exercise increased the number of satellite cells (muscle stem cells) – a number which normally declines with aging. The researchers believe that a decline in the number of these cells and their functionality may prevent proper maintenance of muscle mass and its ability to repair itself, leading to muscle deterioration.
Comparing the performance of rats of different ages and sexes, they found that the number of satellite cells increased after rats ran on a treadmill for 20 minutes a day for a 13-week period. The younger rats showed a 20 percent to 35% increase in the average number of stem cells per muscle fiber retained – and older rats benefited even more significantly, exhibiting a 33% to 47% increase in stem cells.
A good reason to get up and dance
Endurance exercise also improved the levels of “spontaneous locomotion” – the feeling that tells our bodies to just get up and dance – in old rats. Aging is typically associated with a reduced level of spontaneous locomotion.
The combination of aging and a sedentary lifestyle significantly contributes to the development of diseases such as osteoporosis, obesity, diabetes and cardiovascular diseases, as well as a decline in cognitive abilities. If researchers can discover a method to “boost” satellite cells in our muscles, it could simulate the performance of young and healthy muscles and hold our aging bones in place.
“We hope to understand the mechanisms for the activation codes of muscle stem cells at the molecular level,” says Benayahu. “With this advance, we can let ourselves dream about creating a new drug for humans – one that could increase muscle mass and ameliorate the negative effects of aging.”
Grants for the study were provided by the EU-FP7 Excell project; Israel’s Ministry of Health; and the US-Israel Binational Science Foundation jointly with Prof. Yablonka-Reuveni from the University of Washington.