MITOCHONDRIAL LOCALIZATION OF AQUAPORIN-9 IN NORMAL AND PREECLAMPTIC PLACENTAS

FERNANDEZ, NAZARENA; SIERRA, MATIAS N.; SZPILBARG, NATALIA; FAVALE, NICOLAS; MARTINEZ, NORA; DAMIANO, ALICIA E.

Congreso; Symposium of the Latin American Society on Maternal-Fetal Interaction and Placenta (SLIMP); 2024

Objectives: In preeclampsia, increased oxidative stress causes mitochondrial dysfunction, trophoblast apoptosis, and placental insufficiency. Previously, we described an increase in Aquaporin-9 (AQP9) expression inthe trophoblast cells of preeclamptic placentas, though its function isunknown. Recently, we found that AQP9 also localizes in the trophoblastmitochondria of normal placentas with a high expression in the “heavy/large” mitochondrial fraction, while it was almost undetectable in the"light/small" one. Here, we aimed to study the AQP9 expression in themitochondria from preeclamptic trophoblast cells.Methods: This study was approved by the Ethics Committee of Facultad deFarmacia y Bioquímica, Universidad de Buenos Aires (RES CD-2023-836).Placentas were obtained from healthy-term (n=6) and preeclamptic (n=6)pregnancies. The microsomal and the two mitochondrial fractions wereisolated from placental tissue by differential centrifugation. Co-localization of AQP9 and cytochrome-C was assessed by double-immunofluorescence and confocal microscopy. Mitoplast and the outer mitochondrialmembrane (OMM) were obtained by using digitonin. AQP9 expression wasanalyzed by Western blot.Results: AQP9 co-localized with cytochrome C, in both normal and preeclamptic trophoblast cells. AQP9 expression was significantly increased inthe microsomal and in heavy/large mitochondrial fraction (p