[MrsGoo]

FightAging! Newsletter
Friday, November 25, 2011

There have been a number of research results in the past year or two
that suggest the barriers posed by age to the production of
patient-specific cells suitable for stem cell therapies are lower than
first thought. Several research groups have obtained useful cells from
old patients, showing that age-related damage to patient cells is no
barrier to reprogramming them - indeed, the reprogramming appears to
repair many types of damage. Here is another such result: "Somatic
cells reprogrammed into induced pluripotent stem cells (iPSCs) acquire
features of human embryonic stem cells (hESCs) and thus represent a
promising source for cellular therapy of debilitating diseases, such
as age-related disorders. ... Aged somatic cells might possess high
susceptibility to nuclear and mitochondrial genome instability. Hence,
concerns over the [potential of reprogrammed cells to spawn cancer]
due to the lack of genomic integrity may hinder the applicability of
iPSC-based therapies for age-associated conditions. ... Four iPSC
lines were generated from dermal fibroblasts derived from an
84-year-old woman, representing the oldest human donor so far
reprogrammed to pluripotency. ... all aged-iPSCs were able to
differentiate into neurons, re-establish telomerase activity, and
reconfigure mitochondrial ultra-structure and functionality to a
hESC-like state. Importantly, aged-iPSCs exhibited high sensitivity to
drug-induced apoptosis and low levels of oxidative stress and DNA
damage, in a similar fashion as iPSCs derived from young donors and
hESCs. Thus, the occurrence of chromosomal abnormalities within aged
reprogrammed cells might not be sufficient to over-ride the cellular
surveillance machinery and induce malignant transformation through the
alteration of mitochondrial-associated cell death. Taken together, we
unveiled that cellular reprogramming is capable of reversing
aging-related features in somatic cells from a very old subject,
despite the presence of genomic alterations."