Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Sci. Signal., 24 November 2009
Vol. 2, Issue 98, p. ra75
[DOI: 10.1126/scisignal.2000559]

RESEARCH

mTOR Regulation and Therapeutic Rejuvenation of Aging Hematopoietic Stem Cells

Chong Chen1, Yu Liu1, Yang Liu1,2*, and Pan Zheng1,3*

1 Division of Immunotherapy, Department of Surgery, University of Michigan School of Medicine and Comprehensive Cancer Center, Ann Arbor, MI 48109, USA.
2 Department of Internal Medicine, University of Michigan School of Medicine and Comprehensive Cancer Center, Ann Arbor, MI 48109, USA.
3 Department of Pathology, University of Michigan School of Medicine and Comprehensive Cancer Center, Ann Arbor, MI 48109, USA.

Abstract: 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.

* To whom correspondence should be addressed. E-mail: panz{at}umich.edu (P.Z.) and yangl{at}umich.edu (Y.L.)

Citation: C. Chen, Y. Liu, Y. Liu, P. Zheng, mTOR Regulation and Therapeutic Rejuvenation of Aging Hematopoietic Stem Cells. Sci. Signal. 2, ra75 (2009).

Read the Full Text

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
2009: Signaling Breakthroughs of the Year.
E. M. Adler (2010)
Science Signaling 3, eg1
   Abstract »    Full Text »    PDF »
Science Signaling Podcast: 5 January 2010.
M. B. Yaffe and A. M. VanHook (2010)
Science Signaling 3, pc1
   Abstract »    Full Text »

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882