Erythropoietin : An overview – Uses and Side effects

Introduction

Erythropoietin (EPO) is a sialoglycoprotein hormone (MW 34000) produced by peritubular cells of the kidney that is essential for normal erythropoiesis.

NOTE – Erythropoiesis (from Greek ‘erythro’ meaning “red” and ‘poiesis’ meaning “to make” is the process which produces red blood cells (erythrocytes), which is the development from erythropoietic stem cell to mature red blood cell.

It is stimulated by decreased O2 in circulation, which is detected by the kidneys, which then secrete the hormone erythropoietin.

This hormone stimulates proliferation and differentiation of red cell precursors, which activates increased erythropoiesis in the hemopoietic tissues, ultimately producing red blood cells.

Anaemia and hypoxia are sensed by kidney cells and induce rapid secretion of EPO → acts on erythroid marrow and:

(a) Stimulates proliferation of colony forming cells of the erythroid series.

(b) Induces haemoglobin formation and erythro blast maturation.

(c) Releases reticulocytes in the circulation.

The following types of ESAs are available:

• Erythropoietin (Epo)
• Epoetin alfa
• Epoetin beta
• Epoetin zeta
• Darbepoetin alfa
• Methoxy polyethylene glycol-epoetin beta

Uses :-

Erythropoiesis-stimulating agents (ESAs) are medications which stimulate the bone marrow to make red blood cells.

They are used to treat anemia due to end stage kidney disease, chemotherapy, major surgery, or keratin treatments of HIV/AIDS. In these situations they decrease the need for blood transfusion.

Side effects :-

Common side effects may include joint pain, rash, vomiting, and headache. Serious side effects may include heart attack, stroke, increased cancer growth, or pure red cell aplasia. It is unclear if use is safe during pregnancy.