Old Stem Cells are Most Likely Still Useful Stem Cells

There is an intriguing amount of evidence to suggest that the stem cells remaining in the tissues of old people are still quite capable. If removed from the old cellular environments, many aspects of their behavior become similar to those of the same type of stem cell taken from a younger individual, at least in some reports. There is a greater level of accumulated cellular damage in old stem cells, but much of the evidence suggests that this does not provide as great a contribution to degenerative aging as do diminished numbers and diminished activity. Stem cell activity in the old is much declined from youthful levels, as I'm sure regular readers know. This activity is necessary for the support of tissues, supplying replacement somatic cells and generating signals that adjust cell behavior. The loss of regenerative capacity and consequent slow failure of tissue function an important part of the processes of aging. As to whether the principal problem is loss of stem cells or that the stem cells are present but become perpetually quiescent, the evidence is varied. The situation is probably different for different stem cell populations, and to muddy the waters further, these are most likely overlapping issues. The stem cell populations react to the aging of tissues, meaning the rising level of damage and the changing signal environment that results from that damage. This reaction may be to self-renew less readily, decreasing the size of the stem cell population, or to r...
Source: Fight Aging! - Category: Research Authors: Tags: Medicine, Biotech, Research Source Type: blogs