Research ArticleAging

mTOR Regulation and Therapeutic Rejuvenation of Aging Hematopoietic Stem Cells

Sci. Signal.  24 Nov 2009:
Vol. 2, Issue 98, pp. ra75
DOI: 10.1126/scisignal.2000559

You are currently viewing the abstract.

View Full Text
As a service to the community, AAAS/Science has made this article free with registration.


Age-related declines in hematopoietic stem cell (HSC) function may contribute to anemia, poor response to vaccination, and tumorigenesis. Here, we show that mammalian target of rapamycin (mTOR) activity is increased in HSCs from old mice compared to those from young mice. mTOR activation through conditional deletion of Tsc1 in the HSCs of young mice mimicked the phenotype of HSCs from aged mice in various ways. These included increased abundance of the messenger RNA encoding the CDK inhibitors p16Ink4a, p19Arf, and p21Cip1; a relative decrease in lymphopoiesis; and impaired capacity to reconstitute the hematopoietic system. In old mice, rapamycin increased life span, restored the self-renewal and hematopoiesis of HSCs, and enabled effective vaccination against a lethal challenge with influenza virus. Together, our data implicate mTOR signaling in HSC aging and show the potential of mTOR inhibitors for restoring hematopoiesis in the elderly.

View Full Text

Cited By...