Calvero [Public domain] via Wikimedia CommonsAs we age, the ability of our tissues to maintain homeostasis and to repair themselves declines, eventually leading to organ degeneration and failure. Aging of muscle tissue is characterized by deficient muscle regeneration after injury and by altered muscle function and associated atrophy, known as sarcopenia. Some previous work suggests that the age-related decline in regenerative capacity of skeletal muscle can be reversed by exposing tissue from an older animal to the circulatory system of a younger animal, but the circulatory components underlying the reversal have not been identified. Now, researchers from the University of California, Berkeley, led by Irene M. Conboy, report that oxytocin can improve muscle regeneration in older mice.