- Licenciado in Biochemistry, Universidad de Concepción, Concepción, Chile, 2000
- Biochemist, Universidad de Concepción, Concepción, Chile, 2000
- Ph.D., Cell and Molecular Biology, Universidad Austral de Chile, Valdivia, Chile, 2005
Historically we have learnt that the brain is an organ which is nourished mainly by glucose and that neurons are cells that depend upon this sugar. More than a decade ago, it was thought that synaptically-active neurons preferentially use monocarboxylates from glial cells surrounding the synaptic cleft. These monocarboxylates come from glucose breakdown via glycolysis and lactic fermentation in astrocytes. We have recently described that vitamin C inhibit glucose uptake into neurons in a state of glutamatergic synaptic activity. In addition, we have observed that vitamin C is able to activate lactate transport in these cells. This mechanism is tightly regulated and coordinated in both cell types: neurons and astrocytes, managed by fluctuations in cerebral vitamin C concentration that, in turn, are governed by synaptic activity. We are currently studying the molecular mechanisms involved in this effect and also we are exploring these metabolic cooperation events in peripheral systems.
We are also interested in the regulation of vitamin C and glucose transport in peripheral organs, mainly in male reproductive tissue.
- Castro, M.A., Beltrán F.A., Brauchi, S. and Concha I.I. A metabolic switch in brain: glucose and lactate metabolism modulation by ascorbic acid. J Neurochem. 110(2):423-40, 2009.
- Castro, M.A., Angulo, C., Brauchi, S., Nualart, F. and Concha I.I. (2008) Ascrobic acid participates in a general mechanism for concerted glucose transport inhibition and lactate transport stimulation. Plfugers Arch 457(2):519-28.
- Angulo, C., Castro, M.A., Rivas, C., Segretain, D., Maldonado, R., Yañez, A., Slebe, J.C, Vera, J.C, and Concha I.I.(2008) Molecular identification and functional characterization of the vitamin C transporters by Sertoli cells. J Cellular Physiol 217(3):708-16.
- "Castro, M., Pozo, M., García, M.A., Concha, I.I. and Nualart, F. (2007) Intracellular ascorbic acid inhibits transport of glucose by neurons, but not by astrocytes.
J Neurochem 102(3):773-82."
- Astuya, A, Caprile, T., Castro, M., Salazar, K., García, M.A., Reinicke, K., Rodríguez, F., Vera, J.C., Ulloa, V., Low, M. and Nualart, F. Uptake and recicling of vitamin C in normal and tumor nervous system cells. (2005) J Neuroscience Res, 79:146-156.
- Castro, M., Caprile, T., Astuya, A., Millán, C., Reinicke, K., Vera, J.C., Vásquez, O., Aguayo, L. and Nualart, F. (2001). High-affinity sodium–vitamin C co-transporters (SVCT) expression in embryonic mouse neurons. J Neurochem, 78: 815-823.