Erythropoietin

Erythropoietin , also known as erythropoetin, haematopoietin, or haemopoietin, is a <a href="/facts/Glycoprotein/bKPzzW7m">glycoprotein</a> <a href="/facts/Cytokine/SdWpWABH">cytokine</a> secreted mainly by the <a href="/facts/Kidney/HBspPrv9">kidneys</a> in response to cellular <a href="/facts/Hypoxia_(medicine)/JWV04G89">hypoxia</a>; it stimulates <a href="/facts/Red_blood_cell/Kggpq8Jh">red blood cell</a> production (<a href="/facts/Erythropoiesis/HFUbNYAf">erythropoiesis</a>) in the <a href="/facts/Bone_marrow/4dfudk0H">bone marrow</a>. Low levels of EPO (around 10 <a href="/facts/Enzyme_unit/s7aR2VqR">mU</a>/mL) are constantly secreted in sufficient quantities to compensate for normal red blood cell turnover. Common causes of cellular hypoxia resulting in elevated levels of EPO (up to 10 000 mU/mL) include any <a href="/facts/Anemia/AgEPPmg8">anemia</a>, and <a href="/facts/Hypoxemia/n1cqE0JW">hypoxemia</a> due to chronic lung disease.
Erythropoietin is largely synthesized by fibroblast-like type-1 <a href="/facts/Interstitial_cells/VoIzlQlG">interstitial cells</a>, located primarily in the deep <a href="/facts/Renal_cortex/SPHny2Y6">renal cortex</a> in close association with the <a href="/facts/Peritubular_capillary/WJSuILEx">peritubular capillaries</a> and <a href="/facts/Proximal_convoluted_tubule/mkezjse0">proximal convoluted tubule</a>; it is also produced in <a href="/facts/Perisinusoidal_space/2bp5cVM3">perisinusoidal</a> cells in the <a href="/facts/Liver/Rtp4Fk2b">liver</a>. Liver production predominates in the fetal and perinatal period; renal production predominates in adulthood. It is homologous with <a href="/facts/Thrombopoietin/0Whum9R8">thrombopoietin</a>.
<a href="/facts/Exogeny/yHXbIsAa">Exogenous</a> erythropoietin, recombinant human erythropoietin (rhEPO), is produced by <a href="/facts/Recombinant_DNA_technology/dT3PL7M6">recombinant DNA technology</a> in <a href="/facts/Cell_culture/7Qhu13D9">cell culture</a> and are collectively called <a href="/facts/Erythropoiesis-stimulating_agent/2tgXMKrv">erythropoiesis-stimulating agents</a> (ESA): two examples are <a href="/facts/Epoetin_alfa/eHHmCVju">epoetin alfa</a> and <a href="/facts/Epoetin_beta/kYumhujv">epoetin beta</a>. ESAs are used in the treatment of <a href="/facts/Anemia/AgEPPmg8">anemia</a> in <a href="/facts/Chronic_kidney_disease/4YKH9wpo">chronic kidney disease</a>, anemia in <a href="/facts/Myelodysplasia/6ppeUYWk">myelodysplasia</a>, and in anemia from <a href="/facts/Cancer/PVW6n1D0">cancer</a> <a href="/facts/Chemotherapy/fWTLbaUT">chemotherapy</a>. Risks of therapy include death, <a href="/facts/Myocardial_infarction/xoGw0qcG">myocardial infarction</a>, <a href="/facts/Stroke/DwpjdzY0">stroke</a>, <a href="/facts/Venous_thromboembolism/oQAalgo3">venous thromboembolism</a>, and tumor recurrence. Risk increases when EPO treatment raises hemoglobin levels over 11 g/dL to 12 g/dL: this is to be avoided.
rhEPO has been used illicitly as a <a href="/facts/Performance-enhancing_drug/NydFWSGJ">performance-enhancing drug</a>. It can often be detected in blood, due to slight differences from the endogenous protein; for example, in features of <a href="/facts/Posttranslational_modification/KMUayTIc">posttranslational modification</a>.

Erythropoietin open-in-new

Erythropoietin