2.11, 5.9: news.health/glucosamine/life extender?:
. the studies that claimed
glucosamine caused insulin resistance
were looking at acute high doses;
whereas moderate chronic doses
appear to have a beneficial effect .
D-Glucosamine (CAS 3416-24-8,
"Life Extension Update 2010 reported findings
from a study of supplement users which found
a reduced risk of dying in association with
the use of glucosamine and chondroitin
over a five year period."
Ristow and colleagues point to a reason:
. it had previously been assumed that
D-Glucosamine was good for osteoarthritis
but also impaired glucose metabolism
(only in high doses);
however, the mounting evidence suggests that
D-Glucosamine doesn't help osteoarthritis
but does extend life span by
mimicking a low-carbohydrate diet:
it inhibits glycolysis which causes cells to
use amino-acid oxidation as fuel
and induces generation of new mitochondria
[Nature Communications 2014].
see mitochondrial hormesis (mitohormesis):
Harman's free radical theory of aging,
said that loss of antioxidants
was responsible for the effects of aging;
but antioxidants can also cause aging
if they interfere with mitochondrial ROS
(reactive oxygen species).
. calorie restriction, and specifically
reduced glucose metabolism,
extends life span apparently by
the increased formation of mitochondrial ROS .
. hormesis is a dosage concept
where high doses may be unhealthy,
but moderate doses are essential to health
[Exp Gerontol. 2010].