Elderly mice hooked up to the circulatory systems of young adult mice bounce back quickly from broken legs, researchers report May 19 in Nature Communications. The bone-healing finding is the latest in a chain of recent studies exposing the health benefits of young blood on different parts of the body. Last year, scientists discovered that a hit of young blood gave old mice a boost in brain power and even rejuvenated aging muscle cells.
Scientists haven’t yet pinpointed the mysterious helper that lurks in young blood. A molecule previously pegged as responsible for some fountain-of-youth properties may not be so impressive after all, a second new study suggests. The molecule, a protein called GDF11, actually makes muscles wither, researchers contend May 19 in Cell Metabolism.