ABSTRACT: Oxytocin is a nine amino acid peptide involved in a wide spectrum of physiological functions; predominantly those concerning reproduction and differentiation are of interest. Oxytocin receptors are expressed at early developmental stages of mammals, suggesting that oxytocin might be involved in the determination of the germ stem cell line, at the very early stages of mammalian development. In this respect, the proximate aim of the present study was to confirm and further analyze the existence of oxytocin receptors at a very early level of cell commitment, that is, the determination of germ cells derived from embryoid bodies. To achieve our purpose we have cultured mouse embryonic stem cells under conditions inducing formation of embryoid bodies. In this work, ES cells were allowed to aggregate in a novel medium, "Stefanidis medium" from day 0 to day 14 until formed EBs. RNA was isolated from EBs and using RT-PCR we showed that EBs expressed Oct-4, OTR, OT, and DAZL. To demonstrate simultaneous expression immunocytochemistry was preformed, in which EBs showed strong immunoreactivity for both, OTR and DAZL molecular markers. We found that 35% of the cells displayed OTR, using flow cytometry. In addition, this novel medium showed to increase OTR mRNA. We propose, that at least in murine induced embryoid bodies there is simultaneous expression of oxytocin receptors and germ cell markers (DAZL) in many cells (expressing Oct-4). We thus conclude that, the oxytocin might indeed be a molecule playing a leading role in germ cell determination.
Bio Systems 09/2009; 98(2):122-6. · 1.27 Impact Factor
ABSTRACT: To evaluate whether amniotic fluid cells contain cardiomyocyte- and neuron-like cells.
In this experimental study, cells from human amniotic fluid samples were analyzed for mRNA expression of microtubule-associated protein 2 (MAP-2), vimentin and oxytocin (OT) receptor via RT-PCR. Immunocytochemistry was also performed with MAP-2, OT receptor, vimentin and troponin I antibodies.
In all samples, MAP-2, vimentin and mRNA expression were detectable. OT receptor was also detectable. The cells showed strong immunoreactivity for molecular markers of neurogenic cells including MAP-2 and vimentin. The cells also showed strong immunoreactivity for molecular markers of cardiac muscle such as troponin I and for OT receptors. This report also shows that atosiban (an OT antagonist) added to culture medium of amniotic fluid cells did not induce neurogenic and cardiomyogenic differentiation.
The observed concurrent development of cardiomyocyte- and neuron-like cells suggests that amniotic fluid contains progenitor cells and there is bidirectional communication between both cell types.
Fetal Diagnosis and Therapy 03/2009; 25(1):62-6. · 1.05 Impact Factor
ABSTRACT: To evaluate whether amniotic fluid cells contain a germ-like cell subpopulation.
Cells from human amniotic fluid samples were analyzed for messenger RNA expression of Deleted in Azoospermia-Like gene (DAZL) and Oct-4 by reverse transcriptase polymerase chain reaction. DAZL and C-kit protein expression was assessed by flow cytometry. Immunocytochemistry also was performed to determine DAZL-, stage-specific embryonic antigen 4 (SSEA-4)-, and Oct-4-positive cells.
DAZL gene expression in amniotic fluid cells.
Reverse transcriptase polymerase chain reaction, flow cytometric, and immunocytochemical analyses revealed that human amniotic fluid consists of a distinct cell population that expresses DAZL, C-kit, SSEA-4, and Oct-4.
Our results suggest that human amniotic fluid represents a new source for the isolation of human DAZL-, C-kit-, SSEA-4-, and Oct-4-positive stem cells without raising the ethical issues associated with human embryonic research.
Fertility and sterility 12/2007; 90(3):798-804. · 3.97 Impact Factor