Thursday, June 19, 2014
Researchers examined 16 healthy but sedentary men to determine whether old muscle can be regrown. Through this research the authors studied Sarcopenia, which is the significant loss of muscle mass and function that occur as we age. Sacropenia is by product of conditions like diabetes, high cholesterol and obesity. Through findings by FASEB Journal, researchers at the Jean Mayer USDA Human Nutrition Research Centre on Aging at Tufts University were able to identify a muscle-building mechanism that could be important in addressing Sarcopenia.
Out of the 16 men chosen to be part of the study, half of them were in their 20’s and the other half in their 70’s; both age groups led sedentary lives. They were asked to perform a single bout of resistance exercises to trigger muscle growth before and six hours after it.
“In order for the body to make proteins that build muscle, certain genes need to be turned on,” said lead author Donato A. Rivas, Ph.D., a scientist in the Nutrition, Exercise Physiology and Sarcopenia Laboratory at the USDA HNRCA at Tufts University. “We noticed the older people had a lot fewer genes turned on compared to the younger people, showing us their muscles weren’t responding as well to the exercise.”
“One of the steps in building muscle seems to be missing in the older men, preventing them from responding to the exercise as strongly as the younger men did,” Rivas said. “It is possible that the suppression of these microRNAs is setting off a chain of events that is causing older people to be less efficient in developing muscle.” Through this Rivas et all were able to determine that the level of micro RNA and Small RNA molecules, which play an important role in regulating genes was on the lower side in the older men compared to younger lot.
“Age-related muscle loss has been associated with a myriad of other health problems,” said senior author Roger A. Fielding, Ph.D., director of the Nutrition, Exercise Physiology and Sarcopenia Laboratory at the USDA HNRCA at Tufts University. “Muscle mass is closely tied to our metabolism and losing it increases the risk of developing metabolic diseases like type 2 diabetes and cardiovascular disease. We also know that a program of moderate physical activity, including resistance exercises, can strongly influence a person’s chances of maintaining their ability to walk after age 70.”
Fielding, a professor at the Friedman School of Nutrition Science and Policy at Tufts University and the Tufts University School of Medicine noted that besides resistance exercises, other approaches need to be explored to help and preserve muscle in older adults. Owing to the small sample size, more research needs to be conducted.
“A few studies suggest gene therapy, nutrient supplementation or hormone replacement therapy can assist with building muscle.” He added, “Our identification of a possible microRNA target could help advance the study of these largely untested, but promising approaches to promoting muscle growth in older people.”