title: Glycine transporters type 1 inhibitor promotes brain preconditioning against NMDA-induced excitotoxicity.
abstract: Brain preconditioning is a protective mechanism, which can be activated by sub-lethal stimulation of the NMDA receptors (NMDAR) and be used to achieve neuroprotection against stroke and neurodegenerative diseases models. Inhibitors of glycine transporters type 1 modulate glutamatergic neurotransmission through NMDAR, suggesting an alternative therapeutic strategy of brain preconditioning. The aim of this work was to evaluate the effects of brain preconditioning induced by NFPS, a GlyT1 inhibitor, against NMDA-induced excitotoxicity in mice hippocampus, as well as to study its neurochemical mechanisms. C57BL/6 mice (male, 10-weeks-old) were preconditioned by intraperitoneal injection of NFPS at doses of 1.25, 2.5 or 5.0 mg/kg, 24 h before intrahippocampal injection of NMDA. Neuronal death was evaluated by fluoro jade C staining and neurochemical parameters were evaluated by gas chromatography-mass spectrometry, scintillation spectrometry and western blot. We observed that NFPS preconditioning reduced neuronal death in CA1 region of hippocampus submitted to NMDA-induced excitotoxicity. The amino acids (glycine and glutamate) uptake and content were increased in hippocampus of animals treated with NFPS 5.0 mg/kg, which were associated to an increased expression of type-2 glycine transporter (GlyT2) and glutamate transporters (EAAT1, EAAT2 and EAAT3). The expression of GlyT1 was reduced in animals treated with NFPS. Interestingly, the preconditioning reduced expression of GluN2B subunits of NMDAR, whereas did not change the expression of GluN1 or GluN2A in all tested doses. Our study suggests that NFPS preconditioning induces resistance against excitotoxicity, which is associated with neurochemical changes and reduction of GluN2B-containing NMDAR expression.
authors.affiliation: INCT de Medicina Molecular, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena 190, 30130-100, Belo Horizonte, MG, Brazil; Departamento de Cirurgia, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, 30130-100, Belo Horizonte, MG, Brazil. Electronic address: mauroxavier@ufmg.br.
authors.forename: Mauro Cunha Xavier
authors.initials: MC
authors.lastname: Pinto
authors.affiliation: Departamento de Farmacologia, Instituto de Ciência Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, MG, Brazil.
authors.forename: Isabel Vieira de Assis
authors.initials: IV
authors.lastname: Lima
authors.affiliation: INCT de Medicina Molecular, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena 190, 30130-100, Belo Horizonte, MG, Brazil; Departamento de Cirurgia, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, 30130-100, Belo Horizonte, MG, Brazil.
authors.forename: Flávia Lage Pessoa
authors.initials: FL
authors.lastname: da Costa
authors.affiliation: INCT de Medicina Molecular, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena 190, 30130-100, Belo Horizonte, MG, Brazil.
authors.forename: Daniela Valadão
authors.initials: DV
authors.lastname: Rosa
authors.affiliation: Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, MG, Brazil.
authors.forename: Vânia Aparecida
authors.initials: VA
authors.lastname: Mendes-Goulart
authors.affiliation: Departamento de Bioquímica e Imunologia, Instituto de Ciência Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, MG, Brazil.
authors.forename: Rodrigo Ribeiro
authors.initials: RR
authors.lastname: Resende
authors.affiliation: INCT de Medicina Molecular, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena 190, 30130-100, Belo Horizonte, MG, Brazil.
authors.forename: Marco Aurélio
authors.initials: MA
authors.lastname: Romano-Silva
authors.affiliation: Departamento de Farmacologia, Instituto de Ciência Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, MG, Brazil.
authors.forename: Antônio Carlos Pinheiro
authors.initials: AC
authors.lastname: de Oliveira
authors.affiliation: Instituto de Ensino e Pesquisa da Santa Casa de Belo Horizonte, R. Domingos Vieira, 590, Belo Horizonte, MG, Brazil.
authors.forename: Marcus Vinícius
authors.initials: MV
authors.lastname: Gomez
authors.affiliation: Departamento de Cirurgia, Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, 30130-100, Belo Horizonte, MG, Brazil.
authors.forename: Renato Santiago
authors.initials: RS
authors.lastname: Gomez
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D018690:Excitatory Amino Acid Agonists / Q000633:toxicity*; D005452:Fluoresceins; D008401:Gas Chromatography-Mass Spectrometry; D005786:Gene Expression Regulation / Q000187:drug effects; D018698:Glutamic Acid / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D050487:Glycine Plasma Membrane Transport Proteins / Q000037:antagonists & inhibitors*; D006624:Hippocampus / Q000187:drug effects / Q000293:injuries; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016202:N-Methylaspartate / Q000633:toxicity*; D020258:Neurotoxicity Syndromes / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D012521:Sarcosine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D013997:Time Factors; D014316:Tritium / Q000378:metabolism
chemical_list: D018690:Excitatory Amino Acid Agonists; D005452:Fluoresceins; D050487:Glycine Plasma Membrane Transport Proteins; C435025:N-(3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)-3-(4'-phenylphenoxy)propyl)sarcosine; C435731:fluoro jade; D014316:Tritium; D018698:Glutamic Acid; D016202:N-Methylaspartate; D005998:Glycine; D012521:Sarcosine
keywords: Brain preconditioning; Glycine transporter type 1; Neuroprotection; Neurotransmission