Signaling pathways activated during hepatic differentiation and proliferation of amniotic epithelial cells

PÉREZ-PÉREZ, ANTONIO; CASALE, ROBERTO; VARONE, CECILIA L.; JAIME, MARIANA; DUEÑAS, JOSÉ LUIS; MAYMÓ, JULIETA L.; RIEDEL, RODRIGO; PAROLINI, ORNELLA; VICTOR SANCHEZ MARGALET

Mar del Plata

Congreso; LXIV Reunión anual SAIC SAI SAFIS 2019; 2019

The placenta and fetal membranes have recently been proposed as an important stem cells source for regenerative medicine. Amniotic epithelial cells (hAECs) can be isolated from the amnion of the human placenta at term. They express embryonic stem cells markers and they are pluripotent. These characteristics would make hAECs ideal candidates for regenerative medicine. Hepatic failure is one of the major causes of morbidity and mortality worldwide and the available treatments have several obstacles. Stem cells have been spotlighted as alternative sources of hepatocytes because of their potential for hepatogenic differentiation. The adequate regulation of the signalling pathways activated during a differentiation process is the key for the success of such process. The aim of this work was to study some of the main pathways activated in hAECs during their hepatic differentiation process. Hepatic differentiation (HD) was assayed by specific HD medium (EGF + dexamethasone). Immunofluorescence (IF), Western blot (WB), qRT-PCR, PAS staining and MTT assays were performed. We have found that HD significantly induced an increment in Wnt-1 and B-catenin expression in hAECs, measured by qRTPCR, WB and IF. Treatment of hAECs with XAV939 (a B-catenin inhibitor) caused the inhibition of HD, as albumin expression and glycogen synthesis were reduced. In addition, we determined that B-catenin pathway inhibition diminished Ki-67 expression and cell viability, during HD. We have also observed that HD promotes phosphorylation of PI3K and Akt, as determined by WB and IF. We observed a significant increment in nuclear localization of P-Akt during hAECs HD. These results suggest that the activation of the B-catenin and PI3K pathways may be responsible for a successful hepatic differentiation and proliferation of hAECs. Understanding the molecular mechanisms regulating hepatocyte differentiation will significantly facilitate the development of stem cell-based therapy to treat liver diseases.