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From the article:

".. The scientists found that the basic cause of age-related health decline is malfunctioning telomeres — the end caps on cells’ chromosomes that protect them against DNA damage ... DePinho published a study in Nature in January 2011 that demonstrated it was possible to reverse the symptoms of extreme aging in mice by increasing their levels of telomerase, the enzyme that maintains the health of the telomeres ..."

A bit late. Elizabeth Blackburn won the nobel prize for physiology in medicine 2009 for ...

"... The trio has been credited with creating a new field of science, with their investigation of chromosomes and the discovery of an enzyme which they named Telomerase. Telomerase is almost like an anti-ageing solution - it is critical to the regeneration of cells, which are the building blocks of life. If cells cannot replenish, humans are more prone to disease. ..." ~ http://www.abc.net.au/news/stories/2009/10/05/2705473.htm

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I am (unfortunately) not a biologist, but the abstract of their paper in Nature [1] seems to suggest that their research is notable not because they discovered telomerase is related to ageing, but because they figured out why lack of telomerase causes cells to stop regenerating and organs to fail:

We demonstrate that telomere dysfunction activates p53 which in turn binds and represses PGC-1α and PGC-1β promoters, thereby forging a direct link between telomere and mitochondrial biology. We propose that this telomere–p53–PGC axis contributes to organ and metabolic failure and to diminishing organismal fitness in the setting of telomere dysfunction.

[1]: http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...

Also, mice do not suppress their telomerase. Without telomerase, tumors have a hard time getting larger than a golf ball. This is why large mammals like humans actually suppress telomerase expression in most cells. We might survive a golf ball sized tumor. A mouse? No way! There's no value in a mouse suppressing telomerase, so they're designed to have it switched on all the time.

Would we want our telomerase to be switched on all the time? This would probably make us abnormally prone to developing cancer.

This is also why whalers find tumor scars in whales all the time, but never run across whales that are going die of cancer. It's hard for a tumor to get larger than the size of your head. For us, this would likely be fatal. For a whale, it's no big deal.

While you probably wouldn't want full-on telomerase in your 20s might be worth the risk if you're pushing 80 :).

While you probably wouldn't want full-on telomerase in your 20s might be worth the risk if you're pushing 80 :).

Actually, you are much more at risk for cancer in your 80's. That might be the worst possible plan.

There are 7 distinct classes of damage that comprise the wear and tear resulting from aging. Addressing telomeres only addresses one of these. Read and learn:

http://www.scribd.com/doc/522716/Aubrey-de-Grey-SENS

http://www.sens.org/

My point is that you're probably going to die soon anyway, so even with the cancer risk the treatment may well be +EV. Similar to how people are more willing to undergo risky medical treatments when they're already dying.

That is an interesting trade off.

Still good new though, in my opinion. Cancer seems much more tractable than aging. If we can reduce the problem of aging to something that only requires us to additionally solve cancer, I would be ecstatic.

One of the things that cancer is good at is switching "on" telomerase (enabling the cancer to spread), so naturally working out how to switch "off" telomerase in cancer tumors has actually been one of the key vectors in cancer research.

Cancer and aging are really the same problem. If we solve the other 6 forms of molecular damage and dysfunction, but don't solve the problem of cancer, then we all just get to be healthy for about a century, as if we're in our prime, but then die horribly of cancer.

If we shorten all the telomerase in our body to the point where cancers can't do much more than grow to beign side tumor, cancer is prevented from killing us ever.

On the other hand, we must replace all our cells periodically with the same shorten telomerase.

careful here- I'm fairly certain there's more to cancer than just tumors.

Well the major danger from what I understand is tumors metastasizing all over your body. On the other hand, certain special kind of gland cancers start over or under producing vital hormones (for instance tumors of the adrenal glands can induce massive doses of cortisol and/or adrenaline). That ain't so good for you.

This paper is significant because it finds a precise molecular mechanism whereby reduced telomere function affects organ health. From the article,

"We demonstrate that telomere dysfunction activates p53 which in turn binds and represses PGC-1α and PGC-1β promoters, thereby forging a direct link between telomere and mitochondrial biology. We propose that this telomere–p53–PGC axis contributes to organ and metabolic failure and to diminishing organismal fitness in the setting of telomere dysfunction."

Physorg isn't the most reputable science journalism around (heh), but Nature is arguably the most prestigious journal for life science in the world, and everybody involved in the process of publishing this paper, and writing the News & Views article about it, is aware of Elizabeth Blackburn and telomere research.

The more we know about the pathways involved, the more avenues we have for drug development.

The news is actually further down in the article: they've figured out the processes by which telomeres cause these effects.

good point. but from the sound of it, this finding too will likely earn a Nobel. we're talking about something which is very likely a subset of what's going to either achieve immortality, or cure/prevent cancer, or do both!

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