Mitochondrial control of hematopoietic stem cell balance and hematopoiesis

Hematopoietic stem cells (HSCs) are stem cells from mesodermal derivation that reside in bone marrow and provide blood cells for the whole life of an adult individual, through a process called hematopoiesis. The long lasting support of HSCs for hematopoiesis is permitted by the fine regulation of quiescence and division output. Exit from the quiescent state is to produce a committed and/or stem daughter cells, in an event defined asymmetric or symmetric division. A deregulation in the proportion between asymmetric and symmetric divisions is critical in the appearance of hematological disorders ranging from bone marrow failure to hematological malignancies. Over the past years, several studies have indicated how the metabolism of HSCs is determinant in the regulation of HSC quiescence and commitment process. A metabolism shifted to the glycolytic pathway promotes HSCs quiescence and sustainment of hematopoiesis. Boosting mitochondrial respiration promotes the stem cell commitment followed by stem pool exhaustion, and minimal mitochondrial activity is required to maintain the HSCs quiescence. In the present review are discussed the most recent advances in comprehension of the roles of mitochondria in the hematopoiesis and in the division balance.