title: AKT/GSK3β signaling pathway is critically involved in human pluripotent stem cell survival.
abstract: Human embryonic and induced pluripotent stem cells are self-renewing pluripotent stem cells (PSC) that can differentiate into a wide range of specialized cells. Basic fibroblast growth factor is essential for PSC survival, stemness and self-renewal. PI3K/AKT pathway regulates cell viability and apoptosis in many cell types. Although it has been demonstrated that PI3K/AKT activation by bFGF is relevant for PSC stemness maintenance its role on PSC survival remains elusive. In this study we explored the molecular mechanisms involved in the regulation of PSC survival by AKT. We found that inhibition of AKT with three non-structurally related inhibitors (GSK690693, AKT inhibitor VIII and AKT inhibitor IV) decreased cell viability and induced apoptosis. We observed a rapid increase in phosphatidylserine translocation and in the extent of DNA fragmentation after inhibitors addition. Moreover, abrogation of AKT activity led to Caspase-9, Caspase-3, and PARP cleavage. Importantly, we demonstrated by pharmacological inhibition and siRNA knockdown that GSK3β signaling is responsible, at least in part, of the apoptosis triggered by AKT inhibition. Moreover, GSK3β inhibition decreases basal apoptosis rate and promotes PSC proliferation. In conclusion, we demonstrated that AKT activation prevents apoptosis, partly through inhibition of GSK3β, and thus results relevant for PSC survival.
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Romorini
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Ximena
authors.initials: X
authors.lastname: Garate
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Neiman
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Carlos
authors.initials: C
authors.lastname: Luzzani
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Verónica Alejandra
authors.initials: VA
authors.lastname: Furmento
authors.affiliation: Laboratorio de Regulación de Expresión Génica, IQUIBICEN, UBA/CONICET, Dptos. de Química Biológica y de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Buenos Aires, C1428EGA, Argentina.
authors.forename: Alejandra Sonia
authors.initials: AS
authors.lastname: Guberman
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Gustavo Emilio
authors.initials: GE
authors.lastname: Sevlever
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: María Elida
authors.initials: ME
authors.lastname: Scassa
authors.affiliation: Laboratorios de Investigación Aplicada en Neurociencias (LIAN-CONICET), Fundación FLENI, Ruta 9, Km 52.5, Escobar, Buenos Aires, B1625XAF, Argentina.
authors.forename: Santiago Gabriel
authors.initials: SG
authors.lastname: Miriuka
mesh_terms: D002470:Cell Survival; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D000071679:Glycogen Synthase Kinase 3 beta / Q000378:metabolism*; D006801:Humans; D051058:Oncogene Protein v-akt / Q000378:metabolism*; D039904:Pluripotent Stem Cells / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D000071679:Glycogen Synthase Kinase 3 beta; D051058:Oncogene Protein v-akt