Dexamethasone increases angiopoietin-1 and quiescent hematopoietic stem cells: A novel mechanism of dexamethasone-induced hematoprotection

Abstract

Angiopoietin-1 (Ang-1) is known to have hematoprotective effects by increasing the quiescence of hematopoietic stem cells. However, it remains to be determined if the upregulation of Ang-1 and the subsequent increase in the quiescence of hematopoietic stem cells are also involved in the dexamethasone (Dex)mediated bone marrow protection. Here Western blotting and flow cytometric analyses demonstrate that Dex increases the levels of Ang-1 in mouse bone marrow and the quiescence of hematopoietic stem cells. Our data for the first time suggest that the increased quiescence of hematopoietic stem cells provides a novel mechanism of Dex-induced hematoprotection.