Posted on 12/04/2005 12:37:45 PM PST by narses
It's been well established with previous research that an extra copy of the SIR2 gene can promote longevity in yeast, worms and fruit flies. But a counterintuitive experiment that deleted the gene entirely has resulted in one of the longest recorded life-span extensions in any organism. The new study, by scientists at the University of Southern California, suggests that SIR2 promotes, rather than retards, aging. The findings may throw a spanner into the works of biotech companies and their anti-aging drug development programs.
Author of the study, Valter Longo, said deleting the gene altogether in yeast resulted in a dramatically extended life span - up to six times longer than normal - when combined with caloric restriction and/or a mutation in one or two genes, RAS2 and SCH9, that control the storage of nutrients and resistance to cell damage. Longo added that human cells with reduced SIR2 activity also appeared to confirm that SIR2 has a pro-aging effect, but these results were not included in the Cell paper.
Longo believes that SIR2 (and possibly its counterpart in mammals, SIRT1) may stop an organism from entering an extreme survival mode characterized by the absence of reproduction, improved DNA repair and increased protection against cell damage. Organisms usually enter this mode in response to starvation. According to Longo, the SIR2 deletion made the yeast extraordinarily resilient under stress. "We hit them with oxidants, we hit them with heat. They are highly resistant to everything. What they're doing is basically saying, 'I cannot afford to age. I still have to generate offspring, but I don't have enough food to do it now', he remarked."
While any kind of anti-aging treatment for humans is still a long way off, Longo is excited about the possible implications for another area of research. "Cells may be able to speed up their DNA repair efforts. All organisms have the ability to repair harmful mutations in their DNA, whether caused by age, radiation, diet or other environmental factors," said Longo. And while many researchers believe DNA repair systems are already running flat out, the organisms in Longo's experiment suggest otherwise.
Longo's group began studying SIR2 in 2000, just after a well-known set of experiments by Leonard Guarente at MIT showed that over-expression of the SIR2 gene could extend life span beyond its natural limit. But Longo went in the opposite direction. "We were convinced that SIR2 had the potential to be a more potent pro-aging than an anti-aging gene. And the reason was in part because of the similarity with this other gene, called HST1, which negatively regulated so-called protective genes. So we set out to test whether SIR2 could do the opposite of what everybody said it does," he explained. Longo doesn't question Guarente's finding of a moderate increase in life span when SIR2 is over-expressed, but he believes his work shows that much greater potential gains may lie in the opposite direction.
Source: University of Southern California
Good point. And I guess that people who never fought before are the most eager to send others to fight.
In more noble times the leaders led their troops in battle.
Hopefully if such treatment became available they would withhold it until most/all of the Boomers are gone.
We are already going to be stuck with them continuing to screw up this country for the next 20-30 years, let's not extend that.
True but if the age of soldiers goes up .....
Larry Niven in his "Ringworld Novels" give a pretty good account of the results of increased longevity. You keep meeting people (and wives) you knew long ago and the longest lived seemed to be the most risk averse (cowardly).
What a difference if individuals and societies began to realistically think of goals centuries and not decades in the future. Hey I might even live to see a man on Mars or even another star system.
If we eliminate aging the concept of permanent taxpayer-funded retirement becomes silly, and SS goes away completely. One more reason to support this research.
Quote "One other concern - overpopulation. It is almost mandated that some of us die so make room for the young. Even if the young are less than plentiful - do not forget those civilizations and societies who are making huge numbers of their own."
Overpopulation does not exist. There is plenty of room around the world for people to live. This is a liberal strawman.
Thanks for the ping!
thanks, PH
"Overpopulation does not exist..."
Would you accept that populations need to spread out then?
There is much room on earth - however much of it is uninhabitable by mankind as live now unless full development of technology is achieved by all of the populations. Even on land which is habitable...
...clustering leads to disease, starvation and land devastation....For example the continent of Africa has immense natural resources and expanse of land, but the people there cannot seem to exist above poverty unless there has been outside influence. There is room for all yes but can their population be sustained even in favorable conditions?
Not certain what you are saying here - and if I am wrong I would like to know your thoughts. Please don't label me as espousing liberal mantra. Thanks.
I'm wondering if this implies the society of immortals will be a society of pre-adolescents.
Peter Pans.
In some ways, it appeals to me. Sounds like fun.
Well, aren't you the charming little tyke.
It would appear that you get contention because you are contentious. How about if everyone just pays his own way?
"How about if everyone just pays his own way?"
Deal. I don't have to pay your Social Security and Medicare and you don't have to pay for my...my...aw, hell, you figure out something the government gratuitously gives Gen X like it gratuitously provides for the Boomers, and I'll forgo it.
And as long as I'm dreaming, I'd like seniors to vote for the good of the country instead of their pocketbooks for once.
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"I don't think so. People who start wars don't fight in them."
I used to believe that propaganda until I started reading up on it. It turns out that wars are most popular with young males. They have the least to lose (because they have not accumulated much yet) and the most to gain (glory, status, treasure, women). It is the old and established that are reluctant to start wars.
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