title: Vascular endothelial growth factor promotes cardiomyocyte differentiation of embryonic stem cells.
abstract: Embryonic stem cells (ESCs) overexpressing the vascular endothelial growth factor (VEGF) improve cardiac function in mouse models of myocardial ischemia and infarction by mechanisms that are poorly understood. Here we studied the effects of VEGF on cardiomyocyte differentiation of mouse ESCs in vitro. We used flow cytometry to determine the expression of alpha-myosin heavy chain (alpha-MHC), cardiac troponin I (cTn-I), and Nkx2.5 in differentiated ESCs. VEGF (20 ng/ml) significantly enhanced alpha-MHC, cTn-I, and Nkx2.5 expression in differentiated ESCs. Western blot analysis confirmed these findings. We found that VEGF receptor FMS-like tyrosine kinase-1 (Flt-1) and fetal liver kinase-1 (Flk-1) expression increased during ESC differentiation. Antibodies against Flk-1 totally blocked and against Flt-1 partially blocked VEGF-induced NKx2.5-positive-stained cells. The ERK inhibitor PD-098059 abolished VEGF-induced cardiomyocyte differentiation of ESCs. Our results suggest that VEGF promotes cardiomyocyte differentiation predominantly by ERK-mediated Flk-1 activation and, to a lesser extent, by Flt-1 activation. These findings may be of significance for stem cell and growth factor therapies to regenerate failing cardiomyocytes.
authors.affiliation: Harvard Medical School, Boston, MA 02215, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.forename: Ivo
authors.initials: I
authors.lastname: Amende
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Hampton
authors.forename: Yinke
authors.initials: Y
authors.lastname: Yang
authors.forename: Qingen
authors.initials: Q
authors.lastname: Ke
authors.forename: Jiang-Yong
authors.initials: JY
authors.lastname: Min
authors.forename: Yong-Fu
authors.initials: YF
authors.lastname: Xiao
authors.forename: James P
authors.initials: JP
authors.lastname: Morgan
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D048670:MAP Kinase Kinase 4 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D033581:Stem Cell Transplantation; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D019210:Troponin I / Q000235:genetics / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology*; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000235:genetics / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000235:genetics / Q000378:metabolism; D024723:Ventricular Myosins / Q000235:genetics / Q000378:metabolism
chemical_list: D005419:Flavonoids; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins; C484469:Nkx2-5 protein, mouse; D014157:Transcription Factors; D019210:Troponin I; D042461:Vascular Endothelial Growth Factor A; C501163:Flt1 protein, mouse; D040281:Vascular Endothelial Growth Factor Receptor-1; D040301:Vascular Endothelial Growth Factor Receptor-2; D048049:Extracellular Signal-Regulated MAP Kinases; D048670:MAP Kinase Kinase 4; D024723:Ventricular Myosins; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one