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This isn't anything interesting. They took gene-engineered mice that lacked telomerase, and rescued them by giving them telomerase. It's not life extension to

This isn't anything interesting. They took gene-engineered mice that lacked telomerase, and rescued them by giving them telomerase. It's not life extension to fix a problem that you created that shortens life. Fixing premature aging != enhancing longevity in mice without premature aging. "At Harvard, they bred genetically manipulated mice that lacked an enzyme called telomerase that stops telomeres getting shorter. Without the enzyme, the mice aged prematurely and suffered ailments, including a poor sense of smell, smaller brain size, infertility and damaged intestines and spleens. But when DePinho gave the mice injections to reactivate the enzyme, it repaired the damaged tissues and reversed the signs of ageing." There is a therapy that extends non-genetically-crippled mouse life span by 50% that involves p53 and telomerase, but this thing above is not it. http://www.fightaging.org/archives/2008/01/50-maximum-life-extension-in-mice-via-p53-and-telomerase.php http://www.fightaging.org/archives/2008/01/50-maximum-life-e... The good rule of thumb is to never, never get excited about a therapy that rescues mice from an artificially introduced condition of accelerated aging. These things are almost never applicable to normal aging.

geuis 16y ago
You have excellent points here. I wouldn't call it not interesting though. One interesting version of this experiment would be to take these same telomerase-deficient mice and see if they live longer than normal mouse while receiving the enzyme they fail to produce on their own. What this experiment shows is that telomerase is essential to the function of normal body tissues, and that its absence causes severe problems. The next step would be to see if their life-spans are lengthened with continued treatment, if they live as long as a normal mouse, or if their lifespans are indeed shortened even with continued treatment.
- stcredzero 16y ago
  Human beings and other large mammals suppress their telomerase. Why? Because it can save them from cancer. If the cancer cells never mutate to activate their telomerase or the alternative pathway for fixing telomeres, they start to malfunction and die off before the tumor gets larger than about an inch across. Often, this isn't such a big deal for a human. For a mouse, it's a really big deal and they'll probably die. Hence, there's no anti-cancer benefit for a mouse to suppress telomerase, so they're designed to have it "on" all the time. Whales almost never die of cancer. By the time a cancer gets as large as a human's head, the cancer cells have mutated into dysfunction or parasitism of other tumor cells. Tumors that have been around long enough to get that big tend to die off. For a whale, a tumor the size of a human head is no big deal. The folks that still kill whales (for "research") find tumor scars in whales all the time. They just seem to shrug it off. Activating a human being's telomerase in the fashion discussed in the article would likely bring about an early death of cancer.
DavidSJ 16y ago
I too have developed a mouse life-extension technique. Trials show that the simple, low-cost measure of removing mouse traps from your home can increase mouse life expectancy by up to 50%. It's too soon to say whether this same technique could be applicable for humans.

geuis 16y ago

You have excellent points here. I wouldn't call it not interesting though. One interesting version of this experiment would be to take these same telomerase-deficient mice and see if they live longer than normal mouse while receiving the enzyme they fail to produce on their own. What this experiment shows is that telomerase is essential to the function of normal body tissues, and that its absence causes severe problems. The next step would be to see if their life-spans are lengthened with continued treatment, if they live as long as a normal mouse, or if their lifespans are indeed shortened even with continued treatment.

stcredzero 16y ago
Human beings and other large mammals suppress their telomerase. Why? Because it can save them from cancer. If the cancer cells never mutate to activate their telomerase or the alternative pathway for fixing telomeres, they start to malfunction and die off before the tumor gets larger than about an inch across. Often, this isn't such a big deal for a human. For a mouse, it's a really big deal and they'll probably die. Hence, there's no anti-cancer benefit for a mouse to suppress telomerase, so they're designed to have it "on" all the time. Whales almost never die of cancer. By the time a cancer gets as large as a human's head, the cancer cells have mutated into dysfunction or parasitism of other tumor cells. Tumors that have been around long enough to get that big tend to die off. For a whale, a tumor the size of a human head is no big deal. The folks that still kill whales (for "research") find tumor scars in whales all the time. They just seem to shrug it off. Activating a human being's telomerase in the fashion discussed in the article would likely bring about an early death of cancer.

DavidSJ 16y ago

I too have developed a mouse life-extension technique. Trials show that the simple, low-cost measure of removing mouse traps from your home can increase mouse life expectancy by up to 50%. It's too soon to say whether this same technique could be applicable for humans.