…the fountain of youth?

Tissue from the hippocampus of old mice given young blood showed changes in the expression of 200 to 300 genes, particularly in those involved in synaptic plasticity, which underpins learning and memory. They also found changes in some proteins involved in nerve growth.

The infusion of young blood also boosted the number and strength of neuronal connections in an area of the brain where new cells do not grow. This didn’t happen when old mice received old blood.

To find out whether these changes improved cognition, the team gave 12 old mice eight intravenous shots of blood plasma either from a young or an old mouse, over the course of one month. They used plasma rather than whole blood to exclude any effect produced by blood cells.

The mice then took part in a standard memory task to locate a hidden platform in water. The old mice that had received young blood plasma remembered where to find the platform much quicker than the mice on the old plasma.

Of course, this is the theme of many a science fiction story in which a rich evil codger kidnaps youth to drain their blood and preserve his own vitality. But I hope it turns out to be right, and they can figure out how to extract and manufacture whatever it is.

…is extremely unlikely.