TY - JOUR

T1 - High-dose erythropoietin alters platelet reactivity and bleeding time in rodents in contrast to the neuroprotective variant carbamyl-erythropoietin (CEPO).

AU - Kirkeby, Agnete

AU - Torup, Lars

AU - Bochsen, Louise

AU - Kjalke, Marianne

AU - Abel, Kristin

AU - Theilgaard-Mønch, Kim

AU - Johansson, Pär I

AU - Bjørn, Søren E

AU - Gerwien, Jens

AU - Leist, Marcel

N1 - Keywords: Adenosine Diphosphate; Animals; Bleeding Time; Blood Proteins; Collagen; Dose-Response Relationship, Drug; Erythropoietin; Erythropoietin, Recombinant; Male; Mice; Neuroprotective Agents; P-Selectin; Platelet Activation; Platelet Aggregation; Rats; Rats, Sprague-Dawley; Receptors, Proteinase-Activated

PY - 2008

Y1 - 2008

N2 - The haematopoietic hormone erythropoietin (EPO) has neuroprotective properties and is currently being explored for treatment of stroke and other neurological disorders. Short-term, high-dose treatment with EPO seems to improve neurological function of stroke patients but may be associated with increased thrombotic risk, whereas alternative non-erythropoietic neuroprotective derivatives of EPO, such as carbamylated EPO (CEPO), may be devoid of such side-effects. We investigated the effects of short-term, high-dose treatment with EPO and CEPO on platelet function and haemostasis in healthy mice and rats. Animals received three daily doses of EPO or CEPO (50 microg/kg), and blood was compared with respect to alterations in haematology and platelet reactivity. In rats, treatment with EPO increased the haematocrit to >50% and the mean platelet volume by 37%, while CEPO had no effect on these parameters. Platelets from EPO-treated rats showed an increased sensitivity to thrombin receptor agonist peptides and elevated plasma levels of soluble P-selectin (sP-selectin) were found in treated mice. Further indicators of platelet hyperreactivity in EPO, but not CEPO-treated animals, were significantly increased aggregatory responses to collagen in whole blood and platelet-rich plasma (PRP). The increased platelet reactivity was paralleled by a decreased bleeding time after tail transection in rats. Samples from EPO-treated rats showed an attenuated response to ADP in whole blood aggregometry and thrombelastography (TEG) platelet mapping but not in apyrase-treated PRP, suggesting involvement of ADP receptor desensitization. These findings suggest that while EPO affects various aspects of platelet function, CEPO is devoid of such effects.

AB - The haematopoietic hormone erythropoietin (EPO) has neuroprotective properties and is currently being explored for treatment of stroke and other neurological disorders. Short-term, high-dose treatment with EPO seems to improve neurological function of stroke patients but may be associated with increased thrombotic risk, whereas alternative non-erythropoietic neuroprotective derivatives of EPO, such as carbamylated EPO (CEPO), may be devoid of such side-effects. We investigated the effects of short-term, high-dose treatment with EPO and CEPO on platelet function and haemostasis in healthy mice and rats. Animals received three daily doses of EPO or CEPO (50 microg/kg), and blood was compared with respect to alterations in haematology and platelet reactivity. In rats, treatment with EPO increased the haematocrit to >50% and the mean platelet volume by 37%, while CEPO had no effect on these parameters. Platelets from EPO-treated rats showed an increased sensitivity to thrombin receptor agonist peptides and elevated plasma levels of soluble P-selectin (sP-selectin) were found in treated mice. Further indicators of platelet hyperreactivity in EPO, but not CEPO-treated animals, were significantly increased aggregatory responses to collagen in whole blood and platelet-rich plasma (PRP). The increased platelet reactivity was paralleled by a decreased bleeding time after tail transection in rats. Samples from EPO-treated rats showed an attenuated response to ADP in whole blood aggregometry and thrombelastography (TEG) platelet mapping but not in apyrase-treated PRP, suggesting involvement of ADP receptor desensitization. These findings suggest that while EPO affects various aspects of platelet function, CEPO is devoid of such effects.

M3 - Journal article

C2 - 18392330

VL - 99

SP - 720

EP - 728

JO - Thrombosis et diathesis haemorrhagica

JF - Thrombosis et diathesis haemorrhagica

SN - 0340-6245

IS - 4

ER -