title: Creatine affords protection against glutamate-induced nitrosative and oxidative stress.
abstract: Creatine has been reported to exert beneficial effects in several neurodegenerative diseases in which glutamatergic excitotoxicity and oxidative stress play an etiological role. The purpose of this study was to investigate the protective effects of creatine, as compared to the N-Methyl-d-Aspartate (NMDA) receptor antagonist dizocilpine (MK-801), against glutamate or hydrogen peroxide (H2O2)-induced injury in human neuroblastoma SH-SY5Y cells. Exposure of cells to glutamate (60-80 mM) or H2O2 (200-300 μM) for 24 h decreased cellular viability and increased dichlorofluorescein (DCF) fluorescence (indicative of increased reactive oxygen species, ROS) and nitric oxide (NO) production (assessed by mono-nitrogen oxides, NOx, levels). Creatine (1-10 mM) or MK-801 (0.1-10 μM) reduced glutamate- and H2O2-induced toxicity. The protective effect of creatine against glutamate-induced toxicity involves its antioxidant effect, since creatine, similar to MK-801, prevented the increase on DCF fluorescence induced by glutamate or H2O2. Furthermore, creatine or MK-801 blocked glutamate- and H2O2-induced increases in NOx levels. In another set of experiments, the repeated, but not acute, administration of creatine (300 mg/kg, po) in mice prevented the decreases on cellular viability and mitochondrial membrane potential (assessed by tetramethylrhodamine ethyl ester, TMRE, probe) of hippocampal slices incubated with glutamate (10 mM). Creatine concentration-dependent decreased the amount of nitrite formed in the reaction of oxygen with NO produced from sodium nitroprusside solution, suggesting that its protective effect against glutamate or H2O2-induced toxicity might be due to its scavenger activity. Overall, the results suggest that creatine may be useful as adjuvant therapy for neurodegenerative disease treatments.
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil. Electronic address: mauricio.personal@gmail.com.
authors.forename: Mauricio P
authors.initials: MP
authors.lastname: Cunha
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Vicente
authors.initials: V
authors.lastname: Lieberknecht
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Ana Belén
authors.initials: AB
authors.lastname: Ramos-Hryb
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Gislaine
authors.initials: G
authors.lastname: Olescowicz
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Fabiana K
authors.initials: FK
authors.lastname: Ludka
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Carla I
authors.initials: CI
authors.lastname: Tasca
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Nelson H
authors.initials: NH
authors.lastname: Gabilan
authors.affiliation: Department of Biochemistry, Center of Biological Sciences, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Ana Lúcia S
authors.initials: AL
authors.lastname: Rodrigues
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003401:Creatine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D018698:Glutamic Acid / Q000633:toxicity*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D051379:Mice; D018696:Neuroprotective Agents / Q000494:pharmacology*; D015538:Nitrosation / Q000187:drug effects / Q000502:physiology; D009924:Organ Culture Techniques; D018384:Oxidative Stress / Q000187:drug effects* / Q000502:physiology; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D018696:Neuroprotective Agents; D017382:Reactive Oxygen Species; D018698:Glutamic Acid; D003401:Creatine
keywords: Cellular viability; Creatine; Glutamate; Hydrogen peroxide; Nitric oxide