IFIBIO HOUSSAY   25014
INSTITUTO DE FISIOLOGIA Y BIOFISICA BERNARDO HOUSSAY
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Human chorionic gonadotropin downregulates AQP3 expression in human placenta
Autor/es:
DI PAOLA M; MARTÍNEZ N,; FARINA M; MASKIN B; CASTRO PARODI M; DAMIANO A
Lugar:
Mar del Plata
Reunión:
Simposio; VI LatinAmerican Symposium on Maternal-Fetal Interaction & Placenta; 2015
Resumen:
Human chorionic gonadotropin (hCG) is crucial for a successful pregnancy. It is involved in the differentiation of trophoblast cells, so its dysregulation may affect the placental functions. Trophoblast abnormalities have a central role in the pathophysiology of preeclampsia. High levels of hCG are observed in preeclamptic women. Previously, we identified AQP3 and AQP9 in the syncytiotrophoblast of human placenta. In subsequent experiments, we observed that the increased expression of AQP9 found in preeclamptic placentas correlated with high serum levels of hCG, suggesting that this hormone may have a stimulatory effect on AQP9. Regarding AQP3 expression little is known about its regulation in human placenta. Objective: To investigate the expression and localization of AQP3 in normal and preeclamptic placentas, and its behavior at different concentrations of hGC. Methods: This study was approved by the ethics committee of the Hospital Nacional Dr. Prof. Alejandro Posadas, Argentina and written consent was obtained from the patients. HCG serum levels were measured in all the pregnant women. AQP3 expression was analyzed by immunoblotting and immunohistochemistry in normal and preeclamptic placentas. The effect of hCG on AQP3 expression was evaluated in normal placental explants cultured with different concentrations of recombinant hCG. Results: As expected, hCG serum levels were higher in preeclamptic women than in normal ones. However, AQP3 protein expression was significantly reduced in preeclamptic placentas. A similar decrease was observed when explants were cultured with high levels of hCG. In all cases, AQP3 localized in the apical membrane of the syncytiotrophoblast. Conclusions: Our findings showed that high levels of hCG downregulate AQP3 expression in the human placenta. Thus, in preeclamptic placentas, it is possible that the decrease in AQP3 may be related to the increased levels of this hormone. Further studies are needed to determine the role of AQP3 and the consequences of its dysregulation in preeclampsia.