Different degrees of vascularization and their relationship to the expression of vascular endothelial growth factor, placental growth factor, angiopoietins, and their receptors in first-trimester decidual tissues.
OBJECTIVE
To evaluate vascular adaptation to implantation by studying vascularization and angiogenic factors in the decidua basalis (DB), decidua parietalis, and decidual secretory endometrium of first-trimester pregnancies. Comparison of these tissues provides information about the regulation of vascularization by pregnancy-induced hormones and/or the extravillous trophoblast (EVT).


METHODS
Prospective study.


METHODS
Leids University Medical Center (LUMC).


METHODS
Women (n = 32) undergoing voluntarily first-trimester termination of pregnancy.


METHODS
Decidual samples from vacuum-aspiration.


METHODS
Evaluation of vascularization, determined by CD34 immunohistochemistry, and vascular endothelial growth factor-A, placental growth factor (PlGF), vascular endothelial growth factor receptor 1 (Flt-1), vascular endothelial growth factor receptor 2, angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), and TIE-2 protein and messenger RNA (mRNA) expression, determined by reverse transcriptase-polymerase chain reaction and immunohistochemistry, in serial paraffin sections.


RESULTS
Pregnancy-induced hormones and EVT influence vascularization by enhancing the vascular and luminal surface, and by reducing vessel density at the implantation site. These changes correlate with differences in gene and protein expression. Placental growth factor mRNA and PlGF and Flt-1 protein expressions were elevated in DB under the influence of EVT. In addition, the angiopoietins were differentially expressed, in favor of Ang-2, in DB.


CONCLUSIONS
The EVT and pregnancy-induced hormones might be associated with the regulation of vascularization and the expression of angiogenic factors in decidua. The induction of PlGF and Flt-1, and the Ang-2:Ang-1 ratio in DB, suggest that these factors play a role in regulating angiogenesis at the implantation site.
Plaisier
Margreet
M
Department of Biomedical Research, TNO-Quality of Life, Leiden, The Netherlands.
Rodrigues
Sharon
S
Willems
Florian
F
Koolwijk
Pieter
P
van Hinsbergh
Victor W M
VW
Helmerhorst
Frans M
FM
D000328:Adult; D042682:Angiopoietins / Q000096:biosynthesis* / Q000235:genetics; D004717:Endometrium / Q000098:blood supply* / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D000072483:Placenta Growth Factor; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000096:biosynthesis* / Q000235:genetics; D011261:Pregnancy Trimester, First / Q000235:genetics / Q000378:metabolism*; D011446:Prospective Studies; D040262:Receptors, Vascular Endothelial Growth Factor / Q000096:biosynthesis* / Q000235:genetics; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis* / Q000235:genetics
D042682:Angiopoietins; C000608036:PGF protein, human; D011257:Pregnancy Proteins; D042461:Vascular Endothelial Growth Factor A; D000072483:Placenta Growth Factor; D040262:Receptors, Vascular Endothelial Growth Factor