Young blood reverses some age-related impairments

As reported in the prestigious Nature Medicine:

At the cognitive level, systemic administration of young blood plasma into aged mice improved age-related cognitive impairments in both contextual fear conditioning and spatial learning and memory... Our data indicate that exposure of aged mice to young blood late in life is capable of rejuvenating synaptic plasticity and improving cognitive function.

Discussed at a webpage of UC San Francisco:

Anatomically, it was clear that these mice formed more structural and functional connections between neurons, or nerve cells, while they also turned on more genes associated with the formation of new nerve connections.

Furthermore, the researchers found that a protein called Creb became more activated in the brain region known as the hippocampus, and that this increased activity was associated with the anatomical and cognitive improvements the team observed...

Identifying and getting rid of aging factors in old blood, or supplying youthful factors from young blood, might both be worthwhile strategies to combat aging...

There is an AMA with the lead author at the Reddit Journal of Science.