MITOCHONDRIAL METABOLISM IN HUMAN FRESH VILLOUS TROPHOBLAST

MEDINA, YOLLYSETH; CASTRO-PARODI MAURICIO; ACOSTA, LUCAS; ARNAIZ, SILVIA; DAMIANO, ALICIA E; BUSTAMANTE, JUANITA

Ciudad Autonoma de Buenos Aires

Congreso; International Federation of Placenta Associations (IFPA) meeting 2019; 2019

International Federation of Placenta Associations

Objectives: To study different metabolic parameters of the mitochondrial population present in the villous trophoblast in the human term placenta. Methods: This study was approved by the ethics committee of Hospital Nacional Prof. Dr. A. Posadas. After fresh placental tissue dissection, differential ultracentrifugation, followed by flow cytometry analysis of their Forward Scatter (FSC) and Side Scatter (SSC) parameters were performed. Two different mitochondrial fractions were obtained and several mitochondrial metabolic parameters were determined: transmembrane potential(Dym), cardiolipin content, activity of the mitochondrial respiratory complexes as well as the hydrogen peroxide production in both mitochondrial subpopulations. Results: We could confirm the presence of two mitochondrial subpopulations that coexist in fresh human villous trophoblast, described as heavy/large particles with high FSC and light/small particles with lowFSC, both with similar SSC characteristics. Analysis of the Dym showed that the light/small mitochondria are more depolarized as compared with the large/heavy mitochondria subpopulations, with a level of polarization 30% lower than the heavy mitochondrial samples. In addition, the mitochondrial cardiolipin level of the small population was lesser than the observed in the heavy mitochondrial samples, showing 42% of cardiolipin oxidation/depletion, probably due to an induced mitochondrial oxidative process. Conclusion: These results suggest that the mitochondrial population in the human villous trophoblast could exhibit different morphologic and metabolic states. Thus, the respiratory function closely associated to their oxidative processes may regulate the energy demand critical for the progesterone production and cell death process during trophoblast turnover. Consequently, alterations in the mitochondrial function of these subpopulations may be related to the aberrant differentiation in the villous trophoblast observed in preeclampsia.