High levels of human chorionic gonadotropin (hCG) correlate with increased aquaporin-9 (AQP9) expression in explants from human preeclamptic placenta.
Trophoblastic abnormalities have a central role in the pathophysiology of preeclampsia, and some placental hormones, such as human chorionic gonadotropin (hCG), could affect the placental function. Here, we hypothesized that the elevated serum levels of hCG may be involved in the increased aquaporin-9 (AQP9) protein expression in preeclamptic placentas via adenosine 3('),5(')-cyclic phosphate (cAMP) pathways. Normal placental explants were cultured with different concentrations of recombinant hCG or 8-Br-cAMP, a potent analogue of cAMP. We evaluated AQP9 protein expression and localization. After both treatments, we localized AQP9 in the apical membrane of syncytiotrophoblast and in the cytoplasm. We also observed a concentration-dependent effect on AQP9 protein expression. In addition, water uptake increased 1.6-fold in explants treated with hCG. Our results suggest that hCG may increase AQP9 protein expression and functionality via cAMP pathways. Although, in preeclamptic placentas high levels of hCG may upregulate AQP9 protein expression, AQP9 functionality was reduced possibly by other factors.
Marino
Gabriela I
GI
Laboratorio de Canales iónicos-Neurofisiología, Instituto de Investigaciones Médicas A. Lanari, Universidad de Buenos Aires-CONICET, Argentina.
Castro-Parodi
Mauricio
M
Dietrich
Valeria
V
Damiano
Alicia E
AE
D000328:Adult; D020346:Aquaporins / Q000096:biosynthesis*; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000096:biosynthesis / Q000378:metabolism*; D000242:Cyclic AMP / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D010920:Placenta / Q000166:cytology / Q000502:physiology*; D011225:Pre-Eclampsia / Q000378:metabolism*; D011247:Pregnancy; D015398:Signal Transduction / Q000502:physiology; D015854:Up-Regulation / Q000502:physiology*; D055815:Young Adult
C109669:AQP9 protein, human; D020346:Aquaporins; D006063:Chorionic Gonadotropin; D000242:Cyclic AMP