Mitochonria - Of Mice and Men

[SmallIsPower]

I've read that mitochondia is often the cause of aging in humans because they deteriorate faster than our cells. I've heard that's also true in mice, yet humans live 80 years, while mice live just a few. Is our mitochondria that much more robust than a mouse's mitochondria? If that's true, could ours be engineered to last much longer?

[SkepticLance]

Mitochondria as a cause of ageing is still a wee bit controversial. However, they appear to be, at least, part of the story. Mitochondria have their own DNA and manufacture their own enzymes, primarily to carry out the function of energy release. DNA gets slowly damaged over the years, mainly by the chemical products of oxidation, thus making the mitochondria less able to produce the vital enzymes, making them effective as the cell's 'power-house'. This is the suggested cause of ageing.

 

There are enzymes inside our cells designed to attack the products of oxidation. Humans happen to have a hell of a lot of the main one. Thus, oxidants are neutralised very quickly. Mice have a lot less of this enzyme, and their oxidants build up much more quickly. Thus mice mitichondria are damaged much more quickly than human.

 

Incidentally, this is also the source of the widely held belief that consuming lots of food with anti-oxidants (or anti-oxidant pills) will slow or even reverse the ageing process. The only problem with this is that there is little or no empirical evidence to support it, despite many scientists testing the idea.

 

This has not prevented a whole bunch of people and companies from making $$$$ by selling anti-oxidants with the false claim that it will slow ageing.