unrelated yet still starting with thy the thymus may have something to do with programmed physiological change
recent thoughts that partial repair mechanisms may be associated with aging as well as the idea that autoimmunity as well as redirected beneficial immunity might cause repair events a big source of physiological immunochemistry like the thymus may have strong effects
basically the human immune system changes completely with puberty going from a preserve the soma form to a "were outta here" role Thus it is possible that thymus cytokines or hormonal linkages may be associated with the conversion of the human body grow n preserve program of childhood to a mating program where there are theorists that say onset of gene replication is associated with lack of utility of the soma to the genes
I'm under the impression that castration confers longevity a quick look online suggests that castrating rats prior to puberty is more effective at giving longevity which goes with the thymus idea; generally though the improvement was minimal
http://www.ratbehavi...g.htm#Longevitywikipedia says The thymus continues to grow between birth and puberty and then begins to atrophy, a process directed by the high levels of circulating sex hormones. Proportional to thymic size, thymic activity (T cell output) is most active before puberty. Upon atrophy, the size and activity are dramatically reduced, and the organ is primarily replaced with fat (a phenomenon known as "organ involution"). The atrophy is due to the increased circulating level of sex hormones, and chemical or physical castration of an adult results in the thymus increasing in size and activity
Its possible that rather than the sex hormones it is a cytokine released from a tissue responding to the sex hormones that affects the thymus which if it could be blocked would permit puberty with the greater longevity associated with castration
Edited by treonsverdery, 22 April 2009 - 07:39 PM.