Lipid peroxidation and nitrite plus nitrate levels in brain tissue from patients with Alzheimer's disease

Background: Although oxidative stress has been implicated in the pathogenes is of neurodegenerative diseases, data found in the literature are still a matter of controversy. Objective: To study lipid peroxidation and nitrite p lus nitrate levels in brain specimens (frontal, parietal, temporal, and occ ipital cortices) from 8 patients with Alzheimer's disease (AD) in compariso n to 6 young and 7 age-matched controls. Methods: Lipid peroxidation was es timated by the thiobarbiturate test for malonaldehyde and nitrate/nitrite u sing the Griess method. Results: Our results show a clear malonaldehyde inc rease tendency in all brain areas from AD cases in relation to older indivi duals and younger controls. In temporal cortex there was no difference betw een AD cases and age-matched controls. We suggest that this may be due to i ncipient temporal cortex damage in control individuals and that this area c ould be more susceptible to age-related changes. We showed that nitrite plu s nitrate levels significantly decrease in brain areas of AD cases in relat ion to young controls. Except for the frontal cortex, there was a trend for a decreased concentration of nitrite/nitrate in the aged group in all brai n areas studied as compared with young controls. Conclusion: Our results su pport a major role for lipid peroxidation alterations in cerebral cortex of AD patients and showed not only a decrease in nitrite/nitrate levels in fr ontal cortex of AD cases in relation to young and old individuals, but also a reduction in these nitric oxide metabolites in the other cortical areas as related to young controls. Copyright (C) 2000 S. Karger AG. Basel.