Regrowing hearts, lungs, but not brains
Researchers have recently found a way to cause mice to regrow and/or regenerate vital organs: hearts, lungs, appendages, etc. In fact, the only thing that they couldn’t get to regenerate was the brain. Normally, mammals cannot regrow limbs, once they’re lost (unlike certain reptiles), because the genes that control this ability are turned off by default. Ellen Heber-Katz of the Wistar Institute found that by manipulating about a dozen genes, this ability could be turned back on. The whole thing seems rather vague to me, for the simple reason that what genes and how many there were that were altered seems to be unknown. While the results are slated to be revealed this coming week, we’re left dangling in the meantime.
The self-healing mice, from a strain known as MRL, were then subjected to a series of surgical procedures. In one case the mice had their toes amputated — but the digits grew back, complete with joints.
In another test some of the tail was cut off, and this also regenerated. Then the researchers used a cryoprobe to freeze parts of the animals’ hearts, and watched them grow back again. A similar phenomenon was observed when the optic nerve was severed and the liver partially destroyed.
While direct analogs in the human genome are unknown at this point, this could potentially lead to much longer lifespans among humans. It’s almost mind-boggling to think about: imagine an injection of fetal liver cells that would allow an elderly person to have six months of regeneration. Bad hearts are made new, arthritic joins are repaired. I doubt it’s this easy in human beings, of course, so I will retain a modest amount of skepticism for the time being, but I do think that this sort of treatment offers a great deal of hope (somewhere) on the horizon.
What I would like to know is whether stem cell research is involved. If not, this would leapfrog a huge ethical barrier, at least here in the United States. Sadly, though, I suspect that there is, simply because of the phrase “fetal liver cells.” Unfortunately, this regeneration method doesn’t offer any hope for those who choose (or chose) to indulge in reckless recreational habits of questionable legality in the past or present.
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“Unfortunately, this regeneration method doesn’t offer any hope for those who choose (or chose) to indulge in reckless recreational habits of questionable legality in the past or present.”
What exactly do you mean by that? Excessive drinking, smoking, etc…? If so, why couldn’t this method “heal” the affected organs?
Comment by MT — September 12, 2005 @ 11:20 am
I was implying killing brain cells via the substances that will do so. Harder drugs and such.
I’m sure you could regrow or regenerate a liver if you end up with cirrhosis, or grow a new set of lungs if you smoke too much. The article states as much.
Comment by Rian — September 12, 2005 @ 2:51 pm