The rejuvenating effects of young blood is astonishingly effective on mice.
“Who wants to live forever,” Freddy Mercury once memorably sang. While the question was rhetorical, plenty of tech entrepreneurs considered their options and decided that, on balance, they would quite like to, please.
That's why, right now, you can spend $US8,000 on a not-at-all-creepy two litre transfusion of young blood. You might think that that's a pretty rash step to try and reverse the aging process, and while there's no evidence that it works in humans, researchers can at least point to the mouse cage for backup.
And now there's more evidence that young blood rejuvenates mousey brains. Researchers from the University of Stanford have discovered that proteins taken from umbilical cord blood and then injected into the brain rejuvenate elderly mice. Not only do they perform better on behavioural tasks and show improvements to their memory, they even start to build nests again – an ability that gets lost in older mice.
“The really exciting thing about this study, and previous studies that have come before it, is that we've sort of tapped into previously unappreciated potential of our blood - our plasma - and what it can do for reversing the harmful effects of aging on the brain,” lead researcher Joe Castellano told NPR.
But couldn't that be the effect of any old human blood? Apparently not. The study involved three types of blood: samples taken from babies' umbilical cords; young people aged between 19 and 24; and those aged between 61 and 82. The lucky mice that benefited from the human blood (if you can call an injection directly to the brain a lucky event) were aged around 50 in human years.
The mice with umbilical cord blood performed the best, followed by those who got the blood from young people. Those getting blood from the oldest age group displayed no improvements on the tests which involved remembering the way through a maze, and an analysis of brain activity. The mice with the younger injection showed more activity in the hippocampus, and much improved maze performance.
So should we transfer this to humans right away? Maybe, but it's far from a sure thing. Lots of experiments work in mice, but as yet, the trick hasn't found its way to us bipeds. Improving mouse lifespan is pretty easy to do, comparatively speaking, because they're just not built to last in the same way humans are. Or as Rob Howard from University College London put it to The Guardian, "almost everything works in the animals, and so far nothing works in humans".
In other words, further studies are required. Something is certainly going on here, but whether it's unique to mousey physiology remains to be seen, for now. In any case, spending $8,000 on that transfusion would seem premature.