Enhanced in vitro proliferation of aortic endothelial cells from plasminogen activator inhibitor-1-deficient mice.
A number of studies have identified a role for plasminogen activator inhibitor-1 (PAI-1) in regulating angiogenesis, although results from these investigations have been controversial. Among key cellular components of an angiogenic vessel are endothelial cells (ECs), which are known to express several components of the fibrinolytic system, including PAI-1. Thus, alterations in expression of this protein may have direct effects on cell functions involved in vascular development. In this study, ECs were isolated from sections of murine arterial trees from wild-type and PAI-1-deficient mice, and low passage (passages 3-4) homogeneous subpopulations of these cells were obtained by immunomagnetic absorption to antibodies against CD105/CD106. The homogeneity of these cells was further assessed by immunohistochemistry and quantitative real-time reverse transcription-PCR analysis of a number of EC markers. Comparative analyses of EC proliferation (one event associated with angiogenesis) in wild-type and PAI-1-deficient ECs demonstrated enhanced rates of cell growth for PAI-1-deficient cells relative to wild-type cells. Additional studies demonstrated similar levels of both vascular endothelial growth factor (VEGF) mRNA and protein and enhanced levels of VEGF receptor-1 (Flt-1) mRNA in PAI-1-deficient cells relative to wild-type cells. Immunohistochemical analyses indicated that phosphorylation of Akt was also enhanced in PAI-1-deficient cells, implicating VEGF-induced cell signaling alterations in PAI-1-deficient cells, the result of which may contribute to alterations in cell proliferation.
Ploplis
Victoria A
VA
W. M. Keck Center for Transgene Research and the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA. vploplis@nd.edu
Balsara
Rashna
R
Sandoval-Cooper
Mayra J
MJ
Yin
Zhi Jun
ZJ
Batten
Jennifer
J
Modi
Nayan
N
Gadoua
Daniel
D
Donahue
Deborah
D
Martin
J Andrew
JA
Castellino
Francis J
FJ
D000818:Animals; D015703:Antigens, CD; D001011:Aorta / Q000166:cytology* / Q000473:pathology; D015153:Blotting, Western; D002455:Cell Division; D002478:Cells, Cultured; D000071063:Endoglin; D042783:Endothelial Cells / Q000166:cytology*; D004730:Endothelium, Vascular / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010455:Peptides / Q000737:chemistry; D010766:Phosphorylation; D017395:Plasminogen Activator Inhibitor 1 / Q000235:genetics* / Q000502:physiology*; D020033:Protein Isoforms; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D012313:RNA / Q000737:chemistry; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013050:Spectrometry, Fluorescence; D013997:Time Factors; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis
D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; D010455:Peptides; D017395:Plasminogen Activator Inhibitor 1; D020033:Protein Isoforms; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D019010:Vascular Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A; D012313:RNA; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt