Oxidative Stress in the Progression of Alzheimer Disease in the Frontal Cortex
Year: 2010
Type: article
Abstract: We investigated oxidative stress in human postmortem frontal cortexfrom individuals characterized as mild cognitive impairment (n= 8), mild/moderate Alzheimer disease (n = 4), and late-stage Alzheimer disease (n = 9). Samples from subjects with no cognitive impairment (n = 10) that were age- and postmortem interval-matched with these cases were used as controls. The short postmortem intervalbrain samples were processed for postmitochondrial supernatant, nonsynaptic mitochondria, and synaptosome fractions. Samples were analyzed for several antioxidants (glutathione, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, glucose-6-phosphate dehydrogenase, superoxide dismutase, catalase) and the oxidative marker, thiobarbituric acid reactive substances. The tissue was also analyzed for possible changes in protein damage using neurochemical markers for protein carbonyls, 3-nitrotyrosine, 4-hydroxynonenal, andacrolein. All 3 neuropil fractions (postmitochondrial supernatant, mitochondrial, and synaptosomal) demonstrated significant disease-dependent increases in oxidative markers. The highest changes were observed in the synaptosomal fraction. Both mitochondrial and synaptosomal fractions had significant declines in antioxidants (glutathione, glutathione peroxidase, glutathione-S-transferase, and superoxide dismutase). Levels of oxidative markers significantly correlated with Mini-Mental Status Examination scores. Oxidative stress was more localized to the synapses, with levels increasing in a disease-dependent fashion. These correlations implicate an involvement of oxidative stress in Alzheimer disease-related synaptic loss.
Authors: Mubeen A. Ansari, Stephen W. Scheff
Institution: University of Kentucky
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
Funder: National Institute on Aging
OpenAlex ID: W2031762170
