Role of Erythropoietin in Neonates With Hypoxic Ischemic Encephalopathy

Hypoxic-ischemic encephalopathy (HIE) remains a major cause of morbidity and mortality. HIE causes 23% of neonatal deaths . Erythropoietin is a 34kDa glycoprotein that was originally identified because of its role in erythropoiesis. In the fetus, EPO is produced in the liver, and, following the neonatal period, EPO is produced in the kidney and the liver. EPO is a cytokine with pleiotropic functions including erythropoiesis, modulation of inflammatory and immune responses. EPO and the EPO receptor (EPO-R) are expressed by a variety of cell types in the brain including neuronal progenitor cells. EPO transport across the blood-brain barrier is limited by its large size. Only 1% to 2% of circulating EPO crosses the blood-brain barrier under normal circumstances, most likely via passive diffusion . EPO provides a mechanism to maintain or re-establish the function of all other cells in challenging physiological conditions (e.g., hypoxia) . EPO's main role is to prevent apoptosis of erythroid progenitor cells and to enhance their maturation and proliferation . The use of EPO reduces the need for blood transfusions in premature infants. To cross the blood-brain barrier, high doses at 2000 to 5000 IU/kg body weight are administered either early or late for prolonged periods of time. These high doses are well tolerated in preterm infants (i.e., EPO is safe and devoid of untoward complications in this context . In previos studies , The first dose of r-Hu-EPO was administered at 1 to 48 h after birth, followed by doses every other day for 2 weeks. At 18 months-of-age neurodevelopmental outcomes were assessed. Improved long-term outcomes in the r-Hu-EPO-treated infants were evident after moderate HIE, but not in those with severe HIE. There were no side-effects from r-HuEPO treatment .