Hourglass: a blog carnival of biogerontology
July 09 2008 / by mycophage
Category: Health & Medicine Year: General Rating: 6 Hot
(cross-posted from Ouroboros: Research in the biology of aging)
Welcome to the first installation of Hourglass, a blog carnival devoted to the biology of aging. This first issue corresponds with the second blogiversary of Ouroboros, but mostly I consider it a celebration of the excellent (and growing) community of bloggers who are writing about biogerontology, lifespan extension technologies, and aging in general.
Without further ado, then, let’s get started:
Reason at Fight Aging! reports on AnAge, a
curated database of longevity, aging, and life history in a wide
range of animals. The database contains information about average
and maximum longevity within species, and also cool features like
lists of the “world-record” holders for the longest-lived organisms
on the planet. AnAge will be a great tool for anyone interested in
studying
evolution of negligible senescence or exploiting
lifespan diversity across related species to learn about
mechanisms of aging. For those who are interested in databases of
this kind, AnAge is a component of a larger project, the Human Ageing Genomic
Resources.
The most widely studied technique for
extending the lifespan of diverse animals is calorie restriction (CR),
whose benefits in humans are still under careful study. One of the
disadvantages of studying humans, of course, is that you can’t keep
them in completely controlled environments, free from temptation to
cheat on their defined diets — but this may be more than adequately
compensated by the main advantage of human subjects, namely, that
they can tell you how they’re feeling about the study while it’s
underway. Over at Weekly Adventures
of a Girl on a Diet, Elizabeth Ewen describes
her experiences as a subject in the CALERIE study, a large-scale test of the effects
of CR on humans (we’ve discussed CALERIE
here before). In her post, Elizabeth describes the CALERIE study in detail, and also critically assesses
some of its specific features — something that no mouse, however
talented, could ever do. (cont.)
While methods like CR may delay
aging, or at least aspects thereof, they can’t stop it dead in its
tracks — and they certainly can’t reverse large-scale age-related
decline in tissue function. For those applications, we will have to
look to more dramatic interventions, such as tissue engineering. In
this exciting new field, biomedical engineers are seeking,
essentially, to grow new organs for people whose originals have
worn out due to injury, disease, or aging itself. One of the major
challenges of tissue engineering is morphology: Even assuming that
the appropriate sorts of stem cells are available, and that one can
induce them to differentiate appropriately, how would one guarantee
that they grow into the appropriate spatial architecture for
efficient function? According to Attila Csordás at Partial Immortalization, one
solution would be to use the “decellularized
matrix hack“: to chemically or enzymatically remove the cells
from cadaver organs, and then regrow new cells over the
extracellular matrix left behind. (Since ECM is much more highly conserved than cell-surface
markers, I suspect that such an approach could also be used to
overcome immune rejection issues.) Attila’s post includes a video
of the application of this concept to the heart. </p
Moving from the heart to the brain, we’re going to finish up with two huge posts about aging, mental fitness, and age-related changes in neurological function.
Ward Plunet at BrainHealthHacks writes about
recent evidence that
smarter people live longer. This is true whether your metric of
intelligence is education (which could be problematic, as education
levels are often correlated with lifelong affluence and access to
medical care) or whether you’re looking at individual genetic
variations correlated with both longevity and intelligence. It’s a
giant post that quotes several articles from the primary literature
as well as studies by international organizations. Nature, nurture,
Ward has it all.
Assuming for the moment that long
life and intelligence are associated — in which direction does the
causal arrow point? We’re still unsure about that at the level of
the whole organism, but in the case of brain health we know a bit
more. At SharpBrains, Alvaro
Fernandez
interviews U. of Illinois’ Prof. Art Kramer, who describes ways
that everyone can extend their mental healthspans and even delay
the onset of age-related neurological dysfunction such as
Alzheimer’s disease. That’s just the beginning of the lengthy
interview, which goes on to talk about people’s desire for magical
solutions to age-related declines in mental function, the results
of prior studies, and the synergy between physical and cognitive
exercise — among many other subjects.
Thanks for reading. I’m going to try to make Hourglass a monthly carnival on the second Tuesday of every month, so the next one will be held on August 12th. If you’re interested in hosting, please email me.
Comment Thread (1 Response)
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“Evolution Of Negligible Senescence”
I can’t help but notice how this phrase has quite an apt acronym. I wonder if this was a factor to whoever first used it.
Posted by: gremlinn July 09, 2008
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