AQP9-MEDIATED LACTATE TRANSPORT: AN ALTERNATIVE SOURCE OF ENERGY IN PLACENTA

MEDINA, YOLLYSETH; SZPILBARG, NATALIA; REPPETTI, JULIETA; DAMIANO, ALICIA E.

Ciudad Autonoma de Buenos Aires

Simposio; International Symposium of Reproductive Health; 2021

ISRH

Introduction: Emerging evidence shows that placental AQP9 is not involved in the transfer of water between the mother and the fetus. AQP9 is an aquaglyceroporin that also permeates other solutes such as lactate. In other tissues, AQP9 may transport lactate as an alternative energy substrate, having important participation as a nutrient sensor, detecting the availability of nutrients in the cell.Objective: Our aim was to evaluate the participation of AQP9 in the lactate transfer across the human placenta.Methodology: This study was approved by the ethics committee of the Hospital Nacional Dr. Prof. A. Posadas. Explants from normal term placentas were cultured in low glucose with or without L-lactate, and in presence and absence of AQP9 inhibitors (0.3mM HgCl2, a general blocker of AQPs, or 0.5mM Phloretin, to block AQP9). Medium supplemented with glucose was used as control. Cell viability was assessed by MTT assay and LDH release. Apoptosis indexes were analyzed by Bax/Bcl-2 protein expression ratio and TUNEL assay.Results: In low glucose medium, MTT decreased while LDH release did not change compared to controls, suggesting that cell death is not due to necrosis. Moreover, Bax/Bcl-2 ratio and apoptotic nuclei increased (n=5, p