The distinct metabolic profile of hematopoietic stem cells reflects their location in a hypoxic niche.

Bone marrow transplantation is the primary therapy for numerous hematopoietic disorders. The efficiency of bone marrow transplantation depends on the function of long-term hematopoietic stem cells (LT-HSCs), which is markedly influenced by their hypoxic niche. Survival in this low-oxygen microenvironment requires significant metabolic adaptation. Here, we show that LT-HSCs utilize glycolysis instead of mitochondrial oxidative phosphorylation to meet their energy demands. We used flow cytometry to identify a unique low mitochondrial activity/glycolysis-dependent subpopulation that houses the majority of hematopoietic progenitors and LT-HSCs. Finally, we demonstrate that Meis1 and Hif-1alpha are markedly enriched in LT-HSCs and that Meis1 regulates HSC metabolism through transcriptional activation of Hif-1alpha. These findings reveal an important transcriptional network that regulates HSC metabolism.

[1]  M. Simon,et al.  Expansion of human SCID-repopulating cells under hypoxic conditions. , 2003, The Journal of clinical investigation.

[2]  M. Gassmann,et al.  Cellular and developmental control of O2 homeostasis by hypoxia-inducible factor 1 alpha. , 1998, Genes & development.

[3]  M. Poot,et al.  Analysis of mitochondrial morphology and function with novel fixable fluorescent stains. , 1996, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society.

[4]  T. Suda,et al.  Bone marrow long label-retaining cells reside in the sinusoidal hypoxic niche. , 2008, Biochemical and biophysical research communications.

[5]  W M Miller,et al.  Modeling pO(2) distributions in the bone marrow hematopoietic compartment. I. Krogh's model. , 2001, Biophysical journal.

[6]  S. Jagannath,et al.  Enrichment of human hematopoietic stem cell activity in the CD34+Thy-1+Lin- subpopulation from mobilized peripheral blood. , 1995, Blood.

[7]  R. Humphries,et al.  Differential expression of Hox, Meis1, and Pbx1 genes in primitive cells throughout murine hematopoietic ontogeny. , 2002, Experimental hematology.

[8]  I. Weissman,et al.  Analysis of candidate human blood stem cells in "humanized" immune-deficiency SCID mice. , 1993, Leukemia.

[9]  D. Bowtell,et al.  Siah2 Regulates Stability of Prolyl-Hydroxylases, Controls HIF1α Abundance, and Modulates Physiological Responses to Hypoxia , 2004, Cell.

[10]  E. Fuchs,et al.  Socializing with the Neighbors Stem Cells and Their Niche , 2004, Cell.

[11]  E. Papoutsakis,et al.  Reduced oxygen tension increases hematopoiesis in long-term culture of human stem and progenitor cells from cord blood and bone marrow. , 1992, Experimental hematology.

[12]  H. Mizoguchi,et al.  Improvement of culture conditions for human megakaryocytic and pluripotent progenitor cells by low oxygen tension. , 1987, International journal of cell cloning.

[13]  I. Weissman,et al.  The SCID-hu mouse: murine model for the analysis of human hematolymphoid differentiation and function. , 1988, Science.

[14]  T. Kietzmann,et al.  Induction of plasminogen activator inhibitor I gene expression by intracellular calcium via hypoxia-inducible factor-1. , 2004, Blood.

[15]  R. Humphries,et al.  Unraveling the crucial roles of Meis1 in leukemogenesis and normal hematopoiesis. , 2007, Genes & development.

[16]  G. Semenza,et al.  Hypoxia-inducible factor 1 is a basic-helix-loop-helix-PAS heterodimer regulated by cellular O2 tension. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[17]  Michael I. Wilson,et al.  Targeting of HIF-α to the von Hippel-Lindau Ubiquitylation Complex by O2-Regulated Prolyl Hydroxylation , 2001, Science.

[18]  C. Wykoff,et al.  The tumour suppressor protein VHL targets hypoxia-inducible factors for oxygen-dependent proteolysis , 1999, Nature.

[19]  N. Copeland,et al.  Hematopoietic, angiogenic and eye defects in Meis1 mutant animals , 2004, The EMBO journal.

[20]  R. Deberardinis,et al.  Beyond aerobic glycolysis: Transformed cells can engage in glutamine metabolism that exceeds the requirement for protein and nucleotide synthesis , 2007, Proceedings of the National Academy of Sciences.

[21]  R. Johnson,et al.  Dye efflux studies suggest that hematopoietic stem cells expressing low or undetectable levels of CD34 antigen exist in multiple species , 1997, Nature Medicine.

[22]  H. Ryan,et al.  HIF-1 alpha is required for solid tumor formation and embryonic vascularization. , 1998, The EMBO journal.

[23]  G. Semenza,et al.  V-SRC induces expression of hypoxia-inducible factor 1 (HIF-1) and transcription of genes encoding vascular endothelial growth factor and enolase 1: involvement of HIF-1 in tumor progression. , 1997, Cancer research.

[24]  E. Messing,et al.  VHL protein‐interacting deubiquitinating enzyme 2 deubiquitinates and stabilizes HIF‐1α , 2005, EMBO reports.

[25]  K. Parmar,et al.  Distribution of hematopoietic stem cells in the bone marrow according to regional hypoxia , 2007, Proceedings of the National Academy of Sciences.

[26]  Pernilla Eliasson,et al.  The hematopoietic stem cell niche: Low in oxygen but a nice place to be , 2010, Journal of cellular physiology.

[27]  Charles P. Lin,et al.  In vivo imaging of hematopoietic stem cells and their microenvironment , 2009, Journal of biophotonics.

[28]  A. S. Conner,et al.  Isolation and functional properties of murine hematopoietic stem cells that are replicating in vivo , 1996, The Journal of experimental medicine.

[29]  A. Spradling,et al.  Stem cells find their niche , 2001, Nature.

[30]  G. Semenza,et al.  Induction of Hypoxia-inducible Factor 1 Activity by Muscarinic Acetylcholine Receptor Signaling* , 2004, Journal of Biological Chemistry.

[31]  G. Semenza,et al.  HIF-1-mediated expression of pyruvate dehydrogenase kinase: a metabolic switch required for cellular adaptation to hypoxia. , 2006, Cell metabolism.

[32]  G. Semenza,et al.  HIF-1 inhibits mitochondrial biogenesis and cellular respiration in VHL-deficient renal cell carcinoma by repression of C-MYC activity. , 2007, Cancer cell.

[33]  M. Olivotto,et al.  The role of hypoxia in the maintenance of hematopoietic stem cells. , 1993, Blood.

[34]  G. Hodgson,et al.  The effect of oxygen tension on haemopoietic and fibroblast cell proliferation in vitro , 1978, Journal of cellular physiology.

[35]  R. Conaway,et al.  Activation of HIF1alpha ubiquitination by a reconstituted von Hippel-Lindau (VHL) tumor suppressor complex. , 2000, Proceedings of the National Academy of Sciences of the United States of America.

[36]  H. Lodish,et al.  Murine hematopoietic stem cells change their surface phenotype during ex vivo expansion. , 2005, Blood.

[37]  N. Denko,et al.  HIF-1 mediates adaptation to hypoxia by actively downregulating mitochondrial oxygen consumption. , 2006, Cell metabolism.

[38]  E. Papoutsakis,et al.  Oxygen tension alters the effects of cytokines on the megakaryocyte, erythrocyte, and granulocyte lineages. , 1998, Experimental hematology.

[39]  P. Johnston,et al.  HIF-1 and NF-κB-mediated upregulation of CXCR1 and CXCR2 expression promotes cell survival in hypoxic prostate cancer cells , 2007, Oncogene.

[40]  S. Morrison,et al.  Lack of evidence that hematopoietic stem cells depend on N-cadherin-mediated adhesion to osteoblasts for their maintenance. , 2007, Cell stem cell.

[41]  D. Bowtell,et al.  The ubiquitin ligase Siah2 regulates tumorigenesis and metastasis by HIF-dependent and -independent pathways , 2008, Proceedings of the National Academy of Sciences.

[42]  H. Lodish,et al.  Insulin-like growth factor 2 expressed in a novel fetal liver cell population is a growth factor for hematopoietic stem cells. , 2004, Blood.

[43]  Y. S. Cho,et al.  Profiling of differentially expressed genes in human stem cells by cDNA microarray. , 2006, Molecules and cells.

[44]  R. Moreno-Sánchez,et al.  HIF-1alpha modulates energy metabolism in cancer cells by inducing over-expression of specific glycolytic isoforms. , 2009, Mini reviews in medicinal chemistry.

[45]  J. Caro,et al.  Hypoxia-inducible factor 1alpha (HIF-1alpha) protein is rapidly degraded by the ubiquitin-proteasome system under normoxic conditions. Its stabilization by hypoxia depends on redox-induced changes. , 1997, The Journal of biological chemistry.

[46]  H. Nakauchi,et al.  The ABC transporter Bcrp1/ABCG2 is expressed in a wide variety of stem cells and is a molecular determinant of the side-population phenotype , 2001, Nature Medicine.

[47]  Nathan C Boles,et al.  Mouse hematopoietic stem cell identification and analysis , 2009, Cytometry. Part A : the journal of the International Society for Analytical Cytology.

[48]  Caroline C. Blouin,et al.  Hypoxic gene activation by lipopolysaccharide in macrophages: implication of hypoxia-inducible factor 1alpha. , 2004, Blood.

[49]  R. Krumlauf Hox genes in vertebrate development , 1994, Cell.

[50]  T. Imamura,et al.  Frequent co‐expression of HoxA9 and Meis1 genes in infant acute lymphoblastic leukaemia with MLL rearrangement , 2002, British journal of haematology.

[51]  T. Kietzmann,et al.  Hypoxia up-regulates hypoxia-inducible factor-1alpha transcription by involving phosphatidylinositol 3-kinase and nuclear factor kappaB in pulmonary artery smooth muscle cells. , 2007, Molecular biology of the cell.

[52]  B. Torok-Storb,et al.  The ABCG2 transporter is an efficient Hoechst 33342 efflux pump and is preferentially expressed by immature human hematopoietic progenitors. , 2002, Blood.

[53]  G. Semenza,et al.  Hypoxia-Inducible Factor 1 (HIF-1) Pathway , 2007, Science's STKE.

[54]  Linheng Li,et al.  Understanding hematopoietic stem-cell microenvironments. , 2006, Trends in biochemical sciences.

[55]  C. Martínez-A,et al.  The homeodomain protein Meis1 is essential for definitive hematopoiesis and vascular patterning in the mouse embryo. , 2005, Developmental biology.

[56]  M. Ivan,et al.  HIFα Targeted for VHL-Mediated Destruction by Proline Hydroxylation: Implications for O2 Sensing , 2001, Science.

[57]  G. Semenza,et al.  HER2 (neu) Signaling Increases the Rate of Hypoxia-Inducible Factor 1α (HIF-1α) Synthesis: Novel Mechanism for HIF-1-Mediated Vascular Endothelial Growth Factor Expression , 2001, Molecular and Cellular Biology.

[58]  S. Wennström,et al.  Activation of hypoxia-induced transcription in normoxia. , 2005, Experimental cell research.

[59]  B. Chance,et al.  Localization and kinetics of reduced pyridine nucleotide in living cells by microfluorometry. , 1959, The Journal of biological chemistry.