title: Coupling of glutamate and glucose uptake in cultured Bergmann glial cells.
abstract: Glutamate, the main excitatory neurotransmitter in the vertebrate brain, exerts its actions through specific membrane receptors present in neurons and glial cells. Over-stimulation of glutamate receptors results in neuronal death, phenomena known as excitotoxicity. A family of sodium-dependent, glutamate uptake transporters mainly expressed in glial cells, removes the amino acid from the synaptic cleft preventing neuronal death. The sustained sodium influx associated to glutamate removal in glial cells, activates the sodium/potassium ATPase restoring the ionic balance, additionally, glutamate entrance activates glutamine synthetase, both events are energy demanding, therefore glia cells increase their ATP expenditure favouring glucose uptake, and triggering several signal transduction pathways linked to proper neuronal glutamate availability, via the glutamate/glutamine shuttle. To further characterize these complex transporters interactions, we used the well-established model system of cultured chick cerebellum Bergmann glia cells. A time and dose-dependent increase in the activity, plasma membrane localization and protein levels of glucose transporters was detected upon d-aspartate exposure. Interestingly, this increase is the result of a protein kinase C-dependent signaling cascade. Furthermore, a glutamate-dependent glucose and glutamate transporters co-immunoprecipitation was detected. These results favour the notion that glial cells are involved in glutamatergic neuronal physiology.
authors.affiliation: Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del Instituto Politécnico Nacional (IPN), México D.F. 07000, Mexico.
authors.forename: Orquidia G
authors.initials: OG
authors.lastname: Mendez-Flores
authors.affiliation: Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del Instituto Politécnico Nacional (IPN), México D.F. 07000, Mexico.
authors.forename: Luisa C
authors.initials: LC
authors.lastname: Hernández-Kelly
authors.affiliation: Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del Instituto Politécnico Nacional (IPN), México D.F. 07000, Mexico.
authors.forename: Edna
authors.initials: E
authors.lastname: Suárez-Pozos
authors.affiliation: Laboratory of Pediatric Hepatology and Cell Therapy, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires St Luc, Université catholique de Louvain, 1200 Brussels, Belgium.
authors.forename: Mustapha
authors.initials: M
authors.lastname: Najimi
authors.affiliation: Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados (Cinvestav) del Instituto Politécnico Nacional (IPN), México D.F. 07000, Mexico. Electronic address: arortega@cinvestav.mx.
authors.forename: Arturo
authors.initials: A
authors.lastname: Ortega
mesh_terms: D027322:Amino Acid Transport System X-AG; D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism; D002478:Cells, Cultured; D002642:Chick Embryo; D004734:Energy Metabolism / Q000502:physiology; D018846:Excitatory Amino Acids / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism*; D009457:Neuroglia / Q000187:drug effects / Q000378:metabolism*; D018377:Neurotransmitter Agents / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
chemical_list: D027322:Amino Acid Transport System X-AG; D002352:Carrier Proteins; D018846:Excitatory Amino Acids; D018377:Neurotransmitter Agents; D001224:Aspartic Acid; D018698:Glutamic Acid; D011493:Protein Kinase C; D000254:Sodium-Potassium-Exchanging ATPase; D005947:Glucose
keywords: 2-Deoxy D glucose; Bergmann glia; Excitatory amino acid transporters; Glucose transporters