What can a simple newt do that humans are trying to learn? The tiny amphibian can regenerate an entire lopped-off limb, or a whole organ, by taking normal, differentiated body cells--bone, skin, muscle and so on--and winding back their clocks to an undifferentiated state of stemness. Newts create these instant stem cells at the site of an injury, then immediately begin rebuilding the missing body part.

 

Ok, here's my actual question; how can the body convert already specialized cells back into stem cells? And do these cells being converted really come from other parts of the body? Don't they need them?

Does noone know the answers to these questions?

Exactly how newts and other urodele amphibians are able to dedifferentiate cells is an active area of research, and scientists do not yet have a clear idea of the mechanism of regeneration. However, I did read over some reviews on the subject and apparently, scientists believe that some of the homeobox proteins, which play a critical role the differentiation of cells, may also play a role in the dedifferentiation of cells.

What happens in urodeles is a specialized occurance. It has been demonstrated that in ideal conditions, in vitro, we can cause cells to dedifferentiate into stem cell-like cells. They are not stem cells, per se, but have some multipotential capability to proliferate and differentiate into other cell types. There are literally hundreds, if not thousands, of interactions (between proteins and cells) that result in a perfect regenerate. It is not possible for every newt to perfectly regenerate every single time. Humans lack this capability to do this so naturally. Well, with the exception of children regenerating fingertips.

Also, while dedifferentiation is necessary for regeneration, stem cells from neighbouring tissues contribute towards this process. It is more complicated that what the magazine is saying (but I have not read the article).

There are several theories out there of why they can, but we cannot regenerate. I have commented on this in an earlier thread.

 

Newty