Young Blood Rejuvenates Old Muscles
THURSDAY, Feb. 17 (HealthDay News) -- Young blood can help revive damaged older muscles, according to a study that found the blood of aged mice somehow hinders muscle's ability to repair itself.
In the study, researchers from Stanford University focused on specialized cells called satellite cells, which are stem cells sprinkled throughout muscle tissue. These satellite cells are normally dormant but spring into action whenever muscles in young mice are damaged. However, in older mice, satellite cells don't appear to respond to muscle damage.
The Stanford researchers hooked up a group of older mice with a group of younger mice in a way that allowed both groups to share the same blood supply. The researchers then induced muscle damage in the older mice. When these older mice were hooked up to a blood supply from older mice, their muscles healed slowly. But when the older mice received blood from younger mice, their muscles healed much more quickly.
The researchers also studied the livers of older mice who received blood from younger mice. They found that cells that help liver tissue regenerate were more active in older mice when they received younger blood.
The study appears in the Feb. 17 issue of Nature.
The findings indicate that something in younger blood revives regenerative cells in muscle and the liver, the researchers said.
Lead researcher Dr. Thomas Rando, associate professor of neurology and neurological services, suggested that age-related problems in chemicals surrounding the satellite cells, not the cells themselves, might be at fault.
"We need to consider the possibility that the niche in which stem cells sit is as important in terms of stem cell aging as the cells themselves," he said in a prepared statement.
The American Academy of Orthopaedic Surgeons has more about muscle strains and sprains.