Researchers have found a protein in the blood of human umbilical cords that improves memory and learning in old mice. The provocative finding joins a flurry of other recent, sometimes controversial work attempting to find factors that explain the apparent anti-aging properties of young blood.
“These are exciting results,” says Sally Temple, scientific director of the Neural Stem Cell Institute in Rensselaer, New York, who was not involved with the work. She and others say the new finding suggests that this and other factors in young blood may have different, complementary effects on the aging brain.
Decades ago in somewhat grisly experiments, researchers found that sewing together the circulatory systems of an old and young mouse so that they shared the same blood supply rejuvenated the old animals. In 2014, as part of renewed interest in this unusual procedure, known as parabiosis, neuroscientist Tony Wyss-Coray’s lab at Stanford University in Palo Alto, California, reported that it could mimic some of the brain-boosting effects of parabiosis with injections of young mouse plasma, the cell-free part of blood.
Wyss-Coray’s lab recently tested the youngest human blood available—umbilical cord blood, which is traditionally thrown away after a birth but has become increasingly prized as physicians explore its therapeutic uses.