by Delia Lenzi
Villeda et al. (but many others are working on this) in a series of elegant experiments demostrate that age-related synaptic alterations might be reversible. Authors use parabiois to show that young blood contains a factor that reverses some aspects of age-related cognitive impairment in mice.
What is this rejuvenating factor, or, more likely, factors, present in young blood and where is it produced? Comment and overview in Nature.com\News and views,