From: Mike Linksvayer (ml@gondwanaland.com)
Date: Tue Apr 09 2002 - 22:43:27 MDT
On Sun, 2002-04-07 at 16:54, elf quoted "Robert":
> sorry about the lag time...but re:
> ........................
> " ...All of the above not withstanding, one of the general mechanisms
> that
> is thought to lead to lifespan extension through caloric restriction
> is a reduction in metabolism, exhibiting itself as a slightly decreased
> body tempterature, leading to lower free radical production and
> increased longevity. But the details of this are still largely
> unknown.
>
> Robert "
Quoting from a cite posted to the CR list today:
Initial theories that CR acted mainly through retarding growth
and development, reducing the metabolic rate and body fat have not
been born out. CR seems to modify biologic activities at every
level, affecting physiologic, molecular, and genomic processes
[45]. More specifically, CR reduces insulin-like growth factor 1
levels [46], reduces oxidative stress [47] and bolsters DNA repair
and genomic stability [48, 49]. Regarding the latter, Guarente's
group [50] have just identified a mechanism in yeast through which
CR might mediate its effects. CR boosts Sir2, a protein needed for
a phenomenon called silencing which turns genes off at particular
chromosomal regions.
CR doesn't appear to work by slowing down metabolism, though it is
systemic, details unknown as noted.
Mike Linksvayer
http://gondwanaland.com/ml/
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