Evaluation of erythrocyte changes after normoxic return from hypoxia

Abstract

Hypoxia increases erythropoiesis by hypoxia-inducible factors (HIF), principally by HIF-2, which upregulates erythropoietin transcription. This results in an increase of red blood cell (RBC) production and delivery of more oxygen to tissues. Upon rapid return to normoxia, hypoxia-induced polycythemia is overcorrected by neocytolysis, a transient destruction of preferentially young RBCs bearing low catalase (downregulated by hypoxia-stimulated microRNA(miR)-21) caused by reactive oxygen species (ROS) from expanded mitochondria. In order to study molecular mechanism of neocytolysis, it is critical to differentiate life span of young and old RBCs and to measure the hematological changes before and after hypoxia treatment. Here we describe the methodological aspects of these measurements.