Proteins and growth factors in the blood of young mammals may be able to help reverse the aging process in older mammals, The New York Times reports. The finding is based on two studies, both of which found that exposing old mice to the blood supply of young mice can help reverse neurological aging. The first study, published in Nature found that injecting the blood of young mice into old mice stimulated the hippocampus to sprout new connections and caused the old mice to preform better on memory tasks. In the second study, published in Science, researchers found that a young blood supply, or an injection of GDF11, a protein shown previously to be linked to rejuvenate old organs, stimulated vascular growth in the brain. The increased circulation can “revive” dormant stem cells and may have implications for the treatment of age-related diseases, such as Alzheimer’s.