title: Role of the metabotropic P2Y(4) receptor during hypoglycemia: cross talk with the ionotropic NMDAR1 receptor.
abstract: It is well established that both extracellular ATP and glutamate exert a critical role during metabolic impairment, that several P2 receptor subunits are directly involved in this action and that a strong relationship exists between glutamatergic and purinergic signals. Therefore, here we studied the molecular behavior of the purinergic metabotropic P2Y(4) and the glutamatergic ionotropic NMDAR1 receptors during hypoglycemic cell death. We find that these proteins are oppositely modulated during glucose starvation (P2Y(4) is induced, whereas NMDAR1 is inhibited) and that both P2 and NMDA antagonists can restore basal protein expression levels. Moreover, double immunofluorescence experiments with confocal laser microscopy reveal co-localization at the membrane level between the P2Y(4) and NMDAR1 receptors, in both homologous (cerebellar granule neurons) and heterologous (Hek-293) cellular systems. This is furthermore confirmed by co-immunoprecipitation experiments. Finally, when we express the P2Y(4) receptor in the heterologous SH-SY5Y neuronal cell line, hypoglycemia then causes severe cell death and simultaneous downregulation of the NMDAR1 protein. In summary, our work establishes a potential molecular interplay between P2Y(4) and NMDAR1 receptors during glucose deprivation and the causative role of the P2Y(4) during cell death.
authors.affiliation: Fondazione Santa Lucia, Neurobiology Unit, Rome, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Cavaliere
authors.forename: Susanna
authors.initials: S
authors.lastname: Amadio
authors.forename: Daniela F
authors.initials: DF
authors.lastname: Angelini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sancesario
authors.forename: Giorgio
authors.initials: G
authors.lastname: Bernardi
authors.forename: Cinzia
authors.initials: C
authors.lastname: Volonté
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D016923:Cell Death / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D016291:Dizocilpine Maleate / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005947:Glucose / Q000172:deficiency / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D007003:Hypoglycemia / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D058919:Purinergic P2 Receptor Antagonists; D051381:Rats; D017208:Rats, Wistar; D020239:Receptor Cross-Talk / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D014227:Triazines / Q000494:pharmacology
chemical_list: D000255:Adenosine Triphosphate; D016291:Dizocilpine Maleate; D018691:Excitatory Amino Acid Antagonists; D005947:Glucose; D018698:Glutamic Acid; D058919:Purinergic P2 Receptor Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D018048:Receptors, Purinergic P2; D014227:Triazines; C104749:purinoceptor P2Y4; C012842:Cibacron Blue F 3GA