Ok so, most rodents can live about five years - small rodents.
But naked mole rats, this exotic species from africa, can live up to thirty years.
One of the most amazing things is that in all the colonies of naked mole rats kept in
labs around the world, scientists have never once observed them to develop cancer.
That's not true for any other mammal species.
Over the past few years scientists have looked into the naked mole rat cells in petri dishes
and started to find all these interesting mechanisms that might account for why they
can live so long.
When they grow cells in petri dishes, most animal cells grow to extremely high densities.
But naked mole rat cells, they've observed, stop when they're relatively far apart.
This might be related to the fact that they don't develop tumors because tumors are an
uncontrollable cell growth that keeps growing when there's no room for it.
And even when they dosed the naked mole rat cells with carcinogens -- cancer causing chemicals
-- there's no tumors there either.
So one of the explanations for this, scientists have found, might be a chemical called hyaluronan
that builds up between the naked mole rat cells.
Our cells also have hyaluronan, but the naked mole rat's version is five times longer than
ours.
But when the researchers used enzymes to hyaluronan down to our length, they could see tumors
forming in the naked mole rat cells.
Another thing that might be involved with these animals being able to live so long is
these little things inside cells called ribosomes.
Ribosomes are what take the genetic information in your DNA and translate that into proteins
that allow your body to function.
Allow you to live.
And almost every animal species has a particular structure to their ribosomes that has two
pieces.
Researchers have found that the naked mole rats have these really weird ribosomes with
three pieces.
One hypothesis is that these strange ribosomes may be better at accurately translating DNA
into proteins, they make fewer errors.
So to test this, researchers devised this interesting experiment where they took a gene
from a firefly, that's a piece of DNA, and this gene inside the firefly, is responsible
for the fluorescence.
The glow that fireflies give off.
But they interfered with the gene so that it doesn't produce fluorescence unless the
ribosomes make an error when translating it.
And they took this gene and they put it in both naked mole rat cells and mouse cells.
And they found that the naked mole rat cells only shone 10% as brightly -- which means
that the mouse cells made ten times as many errors when translating the protein.
For a fair number of diseases, the build up of inaccurate proteins seems to play a role
in long-term diseases like Alzheimer's.
So the fact that they produce so many fewer inaccurate proteins might be one of the reasons
that naked mole rats are able to live such a long time.