Salamanders can regenerate damaged lungs
Aug 8, 2009 - 2:19:15 PM
The salamander is a super hero of regeneration, able to replace lost limbs, damaged lungs, sliced spinal cord - even bits of lopped-off brain.
But it turns out that this remarkable ability isn't so mysterious after all - suggesting that researchers could learn how to replicate it in people.
Scientists had long credited the diminutive amphibious creature's outsized capabilities to 'pluripotent' cells that, like human embryonic stem cells, have the uncanny ability to morph into whatever appendage, organ or tissue happens to be needed or is due for a replacement.
But a team of seven researchers, including a University of Florida - zoologist, debunk that notion.
Based on experiments on genetically modified axolotl salamanders, the researchers have shown that cells from the salamander's different tissues retain the 'memory' of those tissues when they regenerate, contributing with few exceptions only to the same type of tissue from where they came.
Standard mammal stem cells operate the same way, albeit with far less dramatic results - they can heal wounds or knit bone together, but not regenerate a limb or rebuild a spinal cord.
What's exciting about the new findings is they suggest that harnessing the salamander's regenerative wonders is at least within the realm of possibility for human medical science.
Also, the salamanders heal perfectly, without any scars whatsoever, another ability people would like to learn how to mimic, said Malcolm Maden, professor of biology and author of the paper.
Axolotl salamanders, originally native to only one lake in central Mexico, are evolutionary oddities that become sexually reproducing adults while still in their larval stage.
When an axolotl loses, for example, a leg, a small bump called a blastema forms over the injury. It takes only about three weeks for this blastema to transform into a new, fully functioning replacement leg - not long considering these animals can live 12 or more years.
These findings appeared in the Thursday edition of Nature.
All rights reserved by RxPG Medical Solutions Private Limited ( www.rxpgnews.com )