Vascular endothelial growth factor level changes during human embryo development in culture medium.
OBJECTIVE
Implantation is a complex phenomenon consisting of the first strong contact between embryo and endometrium. Recent studies have demonstrated that this process is dependent not only on the 'readiness' of the endometrium, but also on complex interactions between endometrial and embryonic tissues that cross-talk by means of different molecules (growth factors, cytokines, vasoactive factors). Investigations performed on human blastocysts indicate a role for vascular endothelial growth factor (VEGF) in these processes. The aim of the present study was to investigate VEGF levels at different stages in human embryo culture medium.


METHODS
We selected 20 women among patients undergoing assisted reproduction with the in vitro fertilization-blastocyst transfer protocol. The oocytes were inseminated by intracytoplasmic sperm injection. For each patient, approximately two cultures of four microinjected oocytes (and then of four embryos) were performed. Each culture of four oocytes/embryos was placed in one dish to increase the probability to detect small VEGF concentrations.


RESULTS
Results showed significantly higher VEGF levels in the medium at blastocyst stage (12.16 +/- 2.80 pg/ml) compared with embryos at pronuclear stage (13.58 +/- 2.32 pg/ml) and microinjected oocytes (12.80 +/- 3.45 pg/ml).


CONCLUSIONS
An important VEGF synthesis by blastocysts occurs during human embryo development.
Artini
Paolo Giovanni
PG
Department of Reproductive Medicine and Child Development, Division of Obstetrics and Gynecology, University of Pisa, Pisa, Italy. g.artini@obgyn.med.unipi.it
Valentino
Valeria
V
Monteleone
Patrizia
P
Simi
Giovanna
G
Parisen-Toldin
Maria Rosaria
MR
Cristello
Francesca
F
Cela
Vito
V
Genazzani
Andrea Riccardo
AR
D002478:Cells, Cultured; D002970:Cleavage Stage, Ovum / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D046149:Embryo Culture Techniques; D047108:Embryonic Development / Q000235:genetics* / Q000502:physiology; D005260:Female; D006801:Humans; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis / Q000378:metabolism*
D003470:Culture Media; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A