Regulation of Metabolism and the Role of Redox Factors in the Energy Control of Quiescence and Proliferation of Hematopoietic Cells

Abstract

One of the key regulators of hematopoietic stem cell (HSC) maintenance is cellular metabolism. Resting HSCs use anaerobic glycolysis as the main source of energy. During expansion and differentiation under conditions of steady state hematopoiesis, the energy needs of activated HSC increase many fold. To meet the increased demands, cells switch to mitochondrial oxidative phosphorylation, which is accompanied by the increase in reactive oxygen species (ROS) production. Here, the molecular mechanisms maintaining glycolysis in HSCs as well as the factors determining the increase in metabolic activity and the transition to mitochondrial biogenesis during HSC activation are considered. We focus on the role of HIF (hypoxia-inducible factor) proteins as key mediators of the cellular response to hypoxia, and also consider the phenomenon of extraphysiological oxygen shock (EPHOSS), leading to the forced differentiation of HSCs as well as methods of overcoming it. Finally, the role of fatty acid oxidation (FAO) in hematopoiesis is discussed. Understanding the metabolic needs of normal HSCs and precursors is crucial for the development of new treatments for diseases related to the hematopoietic and immune systems.