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Trophoblast cell lines are important research tools used as a surrogate for primary trophoblast cells in the study of placental function. Because the cellular origins of transformed trophoblasts are likely to be diverse, it would be of value to understand the unique and shared phenotypes of the cells on a global scale. We have compared two widely used cell lines, BeWo and JEG3, by microarray analysis in order to identify differentially expressed genes. Results indicated that approximately 2700 genes were differentially expressed between the cell lines, with principal differences observed in the biological processes of response to stress, cell adhesion, signal transduction, and protein and nucleobase metabolisms. These data suggest that BeWo and JEG3 cell lines, and perhaps other trophoblast cell lines, are sufficiently dissimilar from each other such that they will be differentially suited for specific experimental paradigms.

Objective: Type I diabetes mellitus during pregnancy is associated with dysregulation of the oxygen and glucose metabolic pathways, both of which affect placental villous growth and function. Alteration of placental development in women with diabetes may contribute to the increased risk of preeclampsia, macrosomia, or fetal growth restriction., Methods: To evaluate placental growth in the setting of maternal diabetes, immunohistochemical techniques were used to examine fibroblast growth factor-2 (FGF-2) expression, cell proliferation (Ki67), and apoptosis (Apo-Tag) in placentas from diabetic and nondiabetic patients., Results: Immunostaining for FGF-2 in placentas from diabetic women demonstrated an increase in intensity within the villous stroma and syncytiotrophoblast (P<.05). Associated with these changes in FGF-2 expression, placentas from diabetic women showed no change in villous mitotic activity but did show decreased stromal compartment apoptosis. When expressed as a ratio of Ki67-positive:Apo-Tag-positive nuclei as an index of relative cell turnover, the stromal compartment showed a significant trend towards decreased nuclei turnover (P<.05), suggesting relative tissue growth in diabetic patients., Conclusion: Increased FGF-2 expression and decreased stromal cell compartment turnover in the diabetic placenta might be a compensatory mechanism in response to the altered physiologic milieu of maternal diabetes on placental function.

Objective: We undertook this investigation to explore the effects of ethanol exposure on nitric oxide synthase levels and nitric oxide release. Our hypothesis was that ethanol exposure modifies nitric oxide activity within the placenta as a result of oxidative stress., Study Design: Four 10-g samples of term normal human placental villous tissue were perifused with nonrecirculating Dulbecco's modified Eagle's medium and 25-mmol/L N-[2-hydroxyethyl]piperazine-N'-[2-ethanesulfonic acid] with 0-, 50-, 100-, or 200-mmol/L ethanol. After 2 hours of exposure, tissue was removed, fixed, and frozen for analysis. Immunohistochemical analysis was performed for subtype I or neuronal nitric oxide synthase (nNOS), subtype II or inducible nitric oxide synthase (iNOS), and subtype III or endothelial nitric oxide synthase (eNOS) localization. Western blot analysis was performed for eNOS quantitation. Cyclic guanosine monophosphate and copper-zinc superoxide dismutase levels were measured by electroimmunoassay and kinetic assay, respectively. Nitric oxide release was analyzed by a Sievers nitric oxide analyzer., Results: Immunohistochemical examination confirmed that only eNOS was localized to the syncytiotrophoblasts. After ethanol exposure, eNOS protein expression increased 2.5- to 3.0-fold over that of the control. Tissue cyclic guanosine monophosphate content and nitric oxide release into the effluent were decreased, whereas superoxide dismutase levels were increased at higher ethanol levels (P <.05)., Conclusion: Ethanol exposure appears to induce oxidative stress, which may account for the decreased nitric oxide release, because nitric oxide may be shunted toward scavenging free radicals. Increased eNOS protein expression may be a response to the increased demand for nitric oxide. Decreased nitric oxide availability could adversely affect placental blood flow regulation, which could, in turn, account for the growth restriction seen in ethanol-exposed fetuses.