Chronic inflammation causes loss of bone healing ability in elderly

Washington: A recent study has found out the reason why injured bones do not heal as well with age. The study shows that chronic inflammation is the main reason behind bones ability to heal with time.
The research was published in Proceedings of the National Academy of Sciences (PNAS). The results revolve around the known breakdown, due to wear and tear, of the protein machines and large molecules necessary for the life of human cells, the remnants of which trigger the immune system.
First studied in its role in destroying invading microbes, this system also can react to the body’s own proteins to cause inflammation, a response that fights infection at the site of injury and transitions into the healing process.
“Our results argue that age-associated inflammation called ‘inflamm-aging’ is the culprit in the decline in the number and function of the skeletal stem cells that enable bones to heal,” says senior study author Philipp Leucht, MD, assistant professor in the Departments of Orthopedic Surgery and Cell Biology at NYU School of Medicine.
Diseases that weaken the skeleton are among the most common impairments in the United States, with one report estimating that more than three of every five injuries are to the musculoskeletal system. Seldom fatal, bone fractures greatly diminish the quality of life, say researchers and more so with advanced age, when some fractures never heal.
The current study is based on the observation in human patients that stem cell number in the bone marrow significantly declines with increasing age, and that fractures take longer to heal as the stem cell number drops. The research team then moved to mouse models to explore the related mechanisms.