Shiga toxin type 2 (Stx2) causes the increase in cell volume of human glomerular endothelial cells (HGEC) that showed Aquaporin 1 and Aquaporin 4 (AQP1 and AQP4) expression.

GOMEZ F.; REPPETTI J.; GIRON REYES D.C.; SACERDOTI F.; IBARRA C.; MARTINEZ N.; DAMIANO A.E.; DI GIUSTO G.; AMARAL M.M.

Mar del Plata

Congreso; Reunión anual de las sociedades de biociencias 2022 (SAIC, SAI, FAIC, SAFIS); 2022

Shiga toxin type 2 (Stx2) causes the increase in cell volume of human glomerular endothelial cells (HGEC) that showed Aquaporin 1 and Aquaporin 4 (AQP1 and AQP4) expression.Fernando Gomez1, Julieta Repetti2, Daniel Claudio Girón Reyes1, Flavia Sacerdoti1, Cristina Ibarra1, Nora Martínez2, Alicia Damiano2, Gisela Digiusto3, María Marta Amaral1. 1-Laboratorio de Fisiopatogenia, IFIBIO-Houssay (UBA-CONICET) Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.2-Laboratorio de Biología de la Reproducción, IFIBIO-Houssay (UBA-CONICET) Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.3-Laboratorio de Biomembranas, IFIBIO-Houssay (UBA-CONICET) Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.Hemolytic Uremic Syndrome related to Shiga toxin–producing Escherichia coli (STEC-HUS) is the major cause of acute renal injury in pediatric age groups in Argentina.Previously, we have demonstrated that Stx2 inhibited the net water transport (Jw) across monolayers of HGEC, possibly as a consequence of direct alterations in the Jw mechanisms. In addition, we showed that Stx2 increased the cell area of HGEC and AQPs inhibitors were able to reverse this effect. So, in this work we evaluated changes in cell volume of monolayers of HGEC cells treated with Stx2 as well as we analyze the expression of both AQP1 & AQP4 by these cells. Microscopy, immunohistochemical and immunofluorescence studies were performed in HGEC that were grown on gelatinized glass coverslips (12 mm) and then treated or not with Stx2 for 40 minutes. Images were acquired and digitized using a confocal microscope Olympus FluoView (FV1000). A z-stack consisting of a series of 0.5 µm optical 2D slices was taken from top to bottom of the cells and then 3D reconstructed. The measure of total cell volume and the analysis of AQP1 or AQP4 expression and localization in HGEC cells images were processed using the Surface tool of Imaris 7.1.0 software. Our results showed that HGEC treated with Stx2 exhibited the increase in the cell volume (Stx2: 9374 ± 992 µm3 vs CTRL 4411.15 ± 470 µm3, n=6, p