The Protective Effect of N-Acetylcysteine on Oxidative Stress in the Brain Caused by the Long-Term Intake of Aspartame by Rats
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Long-term intake of aspartame at the acceptable daily dose causes oxidative stress in rodent brain mainly due to the dysregulation of glutathione (GSH) homeostasis. N-Acetylcysteine provides the cysteine that is required for the production of GSH, being effective in treating disorders associated with oxidative stress. We investigated the effects of N-acetylcysteine treatment (150 mg kg−1, i.p.) on oxidative stress biomarkers in rat brain after chronic aspartame administration by gavage (40 mg kg−1). N-Acetylcysteine led to a reduction in the thiobarbituric acid reactive substances, lipid hydroperoxides, and carbonyl protein levels, which were increased due to aspartame administration. N-Acetylcysteine also resulted in an elevation of superoxide dismutase, glutathione peroxidase, glutathione reductase activities, as well as non-protein thiols, and total reactive antioxidant potential levels, which were decreased after aspartame exposure. However, N-acetylcysteine was unable to reduce serum glucose levels, which were increased as a result of aspartame administration. Furthermore, catalase and glutathione S-transferase, whose activities were reduced due to aspartame treatment, remained decreased even after N-acetylcysteine exposure. In conclusion, N-acetylcysteine treatment may exert a protective effect against the oxidative damage in the brain, which was caused by the long-term consumption of the acceptable daily dose of aspartame by rats.
KeywordsN-Acetylcysteine Protective Aspartame Brain Oxidative damage Glutathione
The authors are grateful to the Conselho Nacional de Desenvolvimento Tecnológico (CNPq), to the Comissão de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and to the Fundo de Incentivo a Pesquisa da Universidade Federal de Santa Maria (FIPE-UFSM).
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