[Meta
I apologize for not getting to this sooner, but Yahoo did not send us
a notice of a new message waiting as it usually does and neither I nor
Kitty have looked at the group in the last 3 days. We will have to
check more often from now on even if we do not get a notice.
/Meta --Paul]

Paul,

I figured if anyone would know, you would. Is the potential for rapamycin as
promising as this article suggests?

http://www.physorg.com/news166279683.html

Mark Patterson

[Thanks for posting this Mark.

Yes, this positive rapamycin lifespan study is very interesting, but
for those of us who have been closely following the literature on
everything related to life extension, it was not at all surprising.
Rapamycin is not really an "antibiotic" as some people have stated,
but is rather an inhibitor of cell growth. That is why it is in trials
as a possible anti-cancer therapeutic and it is also the reason for
great caution by a healthy person towards it - it will inhibit the
growth and multiplication of immune cells and may greatly inhibit the
immune response necessary to combat any infection. Many of the same
pathway effects of taking rapamycin (which inhibits a major pathway
regulated by an enzyme called mTOR) can be obtained by many other
supplements and by caloric restriction (CR) or intermittent fasting
(IF). For details on this and several news stories about the rapamycin
study see the thread on sci.life-extension: http://tinyurl.com/nq66jy

BTW, you will notice a major difference in the amount of life
extension quoted in the different stories. The link that you gave
above misinterpreted the study results and used the percentages of
extension of the remaining life at the late age (60 weeks) at which
the rapamycin cohort began taking it. The true figures for total life
extension were 9% for males and 14% for females - a small but still
amazing amount considering that 60 weeks for a mouse is equivalent to
about 60 years for a human. Furthermore, few CR studies have shown
that large an extending when started that late in the life of the
animal under study.

I first got onto rapamycin when mTOR inhibition kept turning up and
showing itself to be a good thing (if not done so strongly that
immunity is also inhibited). Among other things mTOR inhibition and
autophagy promotion are closely related. To find out more about this
read the papers of "Blagosklonny MV" who has been promoting autophagy
and rapapmycin for many years.

Note that the use of rapamycin and the inhibition of mTOR is
completely contrary to the notion of taking hGH for anti-aging
purposes. It has always been my stand that yes, taking hGH will likely
increase the quality of life for a person who has already let hirself
become sarcopenic and generally feeble, and it may even thereby extend
hir lifespan moderately beyond what it would have been if s/he had
remained in the previous state. However, for an already healthy person
who takes all possible steps to not become sarcopenic and feeble, its
use is operating in the wrong direction to the biological pathways
alterations that will extend lifespan.

The bottom line on rapamycin is that I am already doing many things
that are working in the same biochemical pathway direction as the
inhibition of mTOR by rapamycin and because of the immune suppressing
potential, I am still not in any hurry to get some and start taking
it. I will continue to follow the research and after a few more
studies, hopefully some relating to immunity, I will likely consider
trying out a small dosage along with everything else.

Additionally, it should be noted that also this past week was released
the latest results on the rhesus monkey lifespan study, which results
clearly shows that calorie restriction (CR) is highly effective in a
moderately long lived primate (about 1/3 the lifespan of a human).
What these stories do not emphasize, unfortunately, is that
intermittent fasting (IF) has been shown to have the same or better
effects than CR (albeit not as often studied), without the need for
such extreme CR. I and Kitty fast one day out of every three as well
as moderately restrict total calories - we have been doing this for
just over 1 year now. The beauty of IF fasting is that you can get to
feel really full on those days when you do eat. So IMO, IF is a far
more quality of life enhancing method of life extension. --Paul]

[One of several recent articles on the calorie restricted rhesus
monkeys - http://tinyurl.com/kq99v2 in Science News. **Kitty]