EFFECT OF MELATONIN-TREATED TROPHOBLAST EXTRACELLULAR VESICLES ON PLACENTAL ENDOTHELIAL CELL MIGRATION

SZPILBARG NATALIA; REPPETTI JULIETA; SAR JUAN; DAMIANO ALICIA; MARTÍNEZ NORA

CIUDAD DE BUENOS AIRES

Congreso; Reunión Anual de la Sociedad Argentina de Fisiología; 2023

INTRODUCTIONPlacental angiogenesis is indispensable for successful gestation and it is regulated by trophoblast paracrine signaling. In this sense, placental extracellular vesicles (EVs) have been recognized as a major mediator of feto-maternal communication and have been involved in placental angiogenesis regulation. Trophoblast cells synthesize large amounts of melatonin and express its receptors. Melatonin acts in an autocrine and paracrine manner in this organ, prevents the injury produced by oxidative stress and regulates the expression of vascular endothelial growth factor (VEGF).Here, we investigated whether treatment of trophoblast with melatonin can change the content of released placental EVs and modify the biological functions of placental endothelial cells.MATERIALS AND METHODS:This study was approved by the Ethics Committee of Naval Hospital. Placentas were obtained from healthy-term pregnancies (n=3). Placental explants were cultured with and without melatonin (1-20 μM). Tissue viability was evaluated by the MTT assay. Placental EVs were isolated by differential centrifugation, filtration, and ultracentrifugation. EVs were characterized by DLS, NTA, TEM, and western blot for CD63 and HSP70. The EVs-VEGF expression was evaluated by western blot. EA.hy926 placental endothelial cells were treated with placental EVs for 24h and cell migration was assessed by wound healing assays.RESULTS:Trophoblast viability was not altered by the different melatonin concentrations analyzed. VEGF expression was significantly decreased in EVs cultured with 20 μM of melatonin (p