The osteogenic effect of erythropoietin on human mesenchymal stromal cells is dose-dependent and involves non-hematopoietic receptors and multiple intracellular signaling pathways.
Erythropoietin (EPO) is a pleiotropic growth factor. Of interest for skeletal tissue engineering, the non-hematopoietic capabilities of EPO include its osteogenic and angiogenic potencies. The main aim of this study was to investigate the dose-response relationship and determine the lowest effective dose of EPO that reliably increases the osteogenic differentiation of human mesenchymal stromal cells (hMSCs). Additional aims were to elucidate the surface receptors and to investigate the role of the intracellular signaling pathways by blocking the mammalian target of rapamycin (mTOR), Jak-2 protein tyrosine kinase (JAK2), and phosphoinositide 3-kinases (PI3K). The primary outcome measures were two mineralization assays, Arsenazo III and alizarin red, applied after 10, 14, and 21 days. Moreover, alkaline phosphatase activity, cell number, and cell viability were determined after 2 and 7 days. A proportional dose-response relationship was observed. In vivo, the lowest effective dose of 20 IU/ml should be used for further research to accommodate safety concerns about adverse effects. Ex vivo, the most effective dose of 100 IU/ml could facilitate vascularization and bone ingrowth in cell-based scaffolds. The expression of non-hematopoietic receptors EPOR and CD131 was documented, and EPO triggered all three examined intracellular pathways. Future studies of the efficacy of EPO in cell-based tissue engineering can benefit from our findings.
Orthopaedic Research Laboratory, Aarhus University Hospital, Aarhus, Denmark, Noerrebrogade 44, Building 1A, 1.tv, 8000, Aarhus, Denmark, jan.roelfing@ki.au.dk.
Jan Hendrik Duedal
JH
Rölfing
Anette
A
Baatrup
Maik
M
Stiehler
Jonas
J
Jensen
Helle
H
Lysdahl
Cody
C
Bünger
D000730:Androstadienes / Q000494:pharmacology; D002478:Cells, Cultured; D002867:Chromones / Q000494:pharmacology; D053648:Cytokine Receptor Common beta Subunit / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000494:pharmacology*; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D053614:Janus Kinase 2 / Q000037:antagonists & inhibitors / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D009025:Morpholines / Q000494:pharmacology; D010012:Osteogenesis / Q000187:drug effects*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D017467:Receptors, Erythropoietin / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D020123:Sirolimus / Q000494:pharmacology; D013329:Structure-Activity Relationship; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D020032:Tyrphostins / Q000494:pharmacology; D000077191:Wortmannin
D000730:Androstadienes; D002867:Chromones; D053648:Cytokine Receptor Common beta Subunit; D004921:Erythropoietin; D053614:Janus Kinase 2; D009025:Morpholines; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D017467:Receptors, Erythropoietin; D020123:Sirolimus; D058570:TOR Serine-Threonine Kinases; D020032:Tyrphostins; D000077191:Wortmannin; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C546842:MTOR protein, human; C507924:JAK2 protein, human