[extropy-chat] Suppression of Aging in Mice by the Hormone Klotho

[Joao Magalhaes]

Suppression of Aging in Mice by the Hormone Klotho
http://www.sciencemag.org/cgi/content/abstract/1112766

It requires a subscription, so I'll copy the abstract:

"A defect in Klotho gene expression in mice accelerates the degeneration of 
multiple age-sensitive traits. Here we show that overexpression of Klotho 
in mice extends life span. Klotho protein functions as a circulating 
hormone that binds to a cell-surface receptor and represses intracellular 
signals of insulin and insulin-like growth factor-1 (IGF1), an 
evolutionarily conserved mechanism for extending life span. Alleviation of 
aging-like phenotypes in Klotho-deficient mice was observed by perturbing 
insulin/IGF1 signaling, suggesting that Klotho-mediated inhibition of 
insulin/IGF1 signaling contributes to its anti-aging properties. Klotho 
protein may function as an anti-aging hormone in mammals."

I've read the paper and while the lifespan extension (20-30%) is inferior 
to other similar experiments, it is a pretty good work--probably the best 
so far this year. Klotho is now the first gene in mammals that accelerates 
aging when disrupted and extends lifespan when overexpressed--though it can 
be argued that growth hormone is similar in that it extends lifespan when 
disrupted and accelerates aging when overexpressed.

Interestingly, the klotho hormone can be produced, which means that I 
wouldn't be surprised to see companies selling the purified hormone like 
they do for GH within a near future. In fact, I wonder what happens if you 
inject klotho in old people. I don't think they would be 
rejuvenated--nothing in the mice suggests that--, but I wouldn't be 
surprised to see some amelioration of the aging phenotype or of specific 
age-related diseases like osteoporosis.

Cheers,

Joao


---

Joao Pedro de Magalhaes, PhD

Harvard Medical School, Dept. of Genetics
77 Avenue Louis Pasteur, Room 238
Boston, MA 02115
Telephone: 1-617-432-6512

http://www.senescence.info