Old blood carries risks for brain

New transfusion process between young, old mice helps pinpoint effects

mouse hippocampus

FADING YOUTH  Young blood doesn’t kick-start nerve cell division (red cells, left image) in the hippocampus of an old mouse (second from right). And factors in old blood interfere with the process in the brain of a young mouse (second from left).

J. Rebo et al/Nature Communications 2016

Harmful factors circulating in old blood may be partly responsible for the mental decline that can come with age, a small study in mice suggests.