Dr. Tony Wyss-Coray

We have not done, and you know, this question came up many times before, we have actually never fed mice young blood.

You could try that, right?

Because it would have to be absorbed.

The factors would have to be absorbed into the body.

I wouldn't be surprised if some of them wouldn't have beneficial effects and survive sort of the stomach acid environment of the stomach, but nobody's ever done it.

I don't know where it comes from, but it's, yeah.

I mean, there's a lot of these questions and bloodletting too, it's blood thinning also, right?

These leeches release factors into the blood.

And they must have done something, otherwise people would probably not have done it.

Yeah, so it's really interesting that, you know, intuitively you think an organism just ages sort of as a whole in synchrony, we would say, right?

But what researchers have discovered, and this was first, I think Monica Driscoll was the first to show in worms.

that when she looked at the ultrastructural level, that some of these organs in the worm seemed to look more aged than others.

And over the years now, we have molecular tools where we can look at a single cell level or within an organ.

And what we clearly see is that organs and cells within an organism can have slightly different rates of aging.

And the way we conclude that is if we look at all these tissues in many different organisms

every, you know, period of weeks or months in mice, for example, we harvest tissues from different animals, we can see these trajectories that some of them are relatively stable for a long time, and then they start to decline, where others continue to decline from early adulthood.

And yet others, you know, may maintain almost until the animal expires.

So

That allows you then on an individual level to ask, if you compare now one individual to another, do their organs age exactly in the same way?

Or is maybe there a person whose heart ages a little bit faster than their actual, the rest of their body?