So maybe Count Dracula had it right after all. It looks like that young blood has some really good stuff in it. The lab of Tony Wyss-Coray at Stanford has been studying the causes of the aging of the brain. As baby boomers get older and older they get more and more interested in how to keep their brains young.
The Wyss-Coray lab used parabiosis to see if there might be something in the blood that regulates brain aging. Parabiosis is a surgical technique that connects the circulatory systems of two mice. It is sort of like taking two mice and turning them into Siamese twins. Sorry mice, I’m sure it is no fun, but it is for the sake of science. For controls they connected young mice to young mice, and old mice to old. Not surprisingly, nothing much happened.
But when they connected young mice to old mice, Eureka! The brains of the old mice started behaving like they were much younger! The brain stem cells, which normally slow down in old mice, became active and divided more. Neurogenesis, the formation of new neurons, was kicked back on in the old brains. The reverse effects also took place in the young mice receiving old blood. Their cognitive functions declined, as measured by performance on maze tests, and by studies of their synaptic plasticity.
Was the active element in the shared blood cells or plasma? To test this they injected old plasma into young mice and vice versa. They found that the plasma was sufficient for the brain effects, so cells were not necessary. Then they examined the plasma carefully to better define the differences in young and old. They found a cytokine, CCL11, which elevates in concentration in both old mice and people. When they injected CCL11 into the blood of young mice it was able to cause aging effects very similar to that of old blood.
So, if you have a young brain and want an old one, they have the answer. Shoot up some CCL11. But, if you have an old brain and want a young one, the more likely scenario, they still are not sure what to do. Perhaps inactivate your CCL11, maybe with antibodies? They don’t describe this experiment, but it would seem a possibility. Or wait until they discover the active ingredient in the young blood that provides the neuronal fountain of youth? Or hunt the night for beautiful young women, so you can drink their blood?