Browsing by Author "Nualart, Francisco"

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    A characterization of cancer vasculogenic mimicry: Extracellular matrix induced cellular signaling to lumen formation.
    (AMER ASSOC CANCER RESEARCH, 2021) Mingo, Gabriel; Valdivia, Andres; Aldana, Varina; Pradenas, Javiera; Babbitt, Nicole; Gonzalez, Pamela; Nualart, Francisco; Diaz, Jorge; Leyton, Lisette; Bertocchi, Cristina; Owen, Gareth
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    Dynamic expression of the sodium-vitamin C co-transporters, SVCT1 and SVCT2, during perinatal kidney development
    (2013) Nualart, Francisco; Castro, Tamara; Low, Marcela; Henríquez, Juan Pablo; Oyarce, Karina; Cisternas, Pedro; García, Andra; Yañez, Alejandro J.; Bertinat, Romina; Montecinos Acuña, Viviana; García Robles, María Angeles
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    Fact or Fiction, It Is Time for a Verdict on Vasculogenic Mimicry?
    (2019) Valdivia Román, Andrés Felipe; Mingo Orsini, Gabriel Antonio; Aldana, Varina; Pinto, Mauricio P.; Ramírez, Marco; Retamal, Claudio; González, Alfonso; Nualart, Francisco; Corválan, Alejandro H.; Owen, Gareth Ivor
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    Glucose increases intracellular free Ca2+ in tanycytes via ATP released through connexin 43 hemichannels
    (Wiley Periodicals, Inc., 2012) Orellana Roca, Juan Andrés; Sáez Pedraza, Pablo José; Cortés-Campos, Christian; Elizondo, Roberto J.; Shoji Sánchez, Kenji Fabricio; Contreras Duarte, Susana de las Mercedes; Figueroa, Vania; Velarde Aliaga, María Victoria; Jiang, Jean X.; Nualart, Francisco; Sáez, Juan Carlos; García, María A.
    The ventromedial hypothalamus is involved in regulating feeding and satiety behavior, and its neurons interact with specialized ependymal-glial cells, termed tanycytes. The latter express glucose-sensing proteins, including glucose transporter 2, glucokinase, and ATP-sensitive K+ (KATP) channels, suggesting their involvement in hypothalamic glucosensing. Here, the transduction mechanism involved in the glucose-induced rise of intracellular free Ca2+ concentration ([Ca2+]i) in cultured beta-tanycytes was examined. Fura-2AM time-lapse fluorescence images revealed that glucose increases the intracellular Ca2+ signal in a concentration-dependent manner. Glucose transportation, primarily via glucose transporters, and metabolism via anaerobic glycolysis increased connexin 43 (Cx43) hemichannel activity, evaluated by ethidium uptake and whole cell patch clamp recordings, through a KATP channel-dependent pathway. Consequently, ATP export to the extracellular milieu was enhanced, resulting in activation of purinergic P2Y1 receptors followed by inositol trisphosphate receptor activation and Ca2+ release from intracellular stores. The present study identifies the mechanism by which glucose increases [Ca2+]i in tanycytes. It also establishes that Cx43 hemichannels can be rapidly activated under physiological conditions by the sequential activation of glucosensing proteins in normal tanycytes