To Edouard & JP,
This is a fascinating discussion.
Thank you, Edouard, for sharing the paper and to JP for balanced comments.
Do you think that your result (no extension of lifespan) may indicate that a buildup of deleterious “factors” is the cause of aging, rather than a deficency of “good factors”? If that was the case, plasma would need to be treated to lower levels of certain factors in order to see an effect.
On Sun, Jan 25, 2015 at 2:56 PM, J Pedro Magalhaes wrote:
Yes, I am aware that this old paper has some flaws. I don’t think
it’s a simple experiment, however, both to perform and interpret.
Likewise the injections of young blood are also not simple since the
administration method could have an impact. For instance, I can see
you also employed IP injections, which I found a bit strange. one
could also argue that the schedule of injections has an effect
(i.e., you might have to do injections of young blood more
frequently to observe an effect).
so I don’t think any of these studies is conclusive. I maintain my
opinion that parabiosis may not be affecting aging (or maybe it’s
beneficial to some aspects of aging but detrimental to others), and
your results point in that direction, but I think there is still
room for larger and more controlled lifespan experiments.
On 24/01/2015 23:21, Edouard Debonneuil
you, in that old paper that I had read in details
things are actually not so clear: