Lege Artis Medicinae

[PLEIOTROPIC FUNCTIONS OF ERYTHROPOIETIN]

NAGY Judit, KISS István

DECEMBER 20, 2007

Lege Artis Medicinae - 2007;17(12)

[Erythropoietin produced by the foetal liver and the adult kidney is the major stimulator of erythropoiesis. Erythropoietin production is regulated by hypoxic activation of erythropoietin gene transcription. Recently, new sites of erythropoietin production have been found mainly in the central nervous system and in the cardiovascular system. These tissues have a paracrine and/or autocrine system of erythopoietin. The pleiotropic function of erythropoietin in these systems is tissue and cell protection by several mechanisms including inhibition of apoptosis, attenuation of ischaemic or reperfusion injury, anti-inflammatory and antioxidative effects. Furthermore, it promotes vascular recovery and enhances neoangiogenesis. In vivo and in vitro studies have proved that systemically administered human erythropoietin can also provide tissue protection. However, adverse effects of erythropoietin treatment such as hypertension, hyperviscosity and thrombosis may override the beneficial effect of systemic erythropoietin treatment. There are preliminary data that erythropoietin analogues, e.g., asyaloerythropoietin or carbamylated erythropoietin can provide tissue protection without stimulating erythropoiesis.]

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