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Updated: Jul 19, 2026
15:04
Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
Published on: September 28, 2019
Mitochondrial abnormalities in Alzheimer's disease.
1Institute of Pathology, Department of Neurology, Case Western Reserve University, Cleveland, Ohio 44106, USA.
Summary
Mitochondrial abnormalities, including increased mitochondrial DNA (mtDNA) and cytochrome oxidase, are linked to oxidative damage in Alzheimer's disease neurons. These changes suggest an early association between mitochondrial dysfunction and neurodegeneration in Alzheimer's disease.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Oxidative damage is observed in Alzheimer's disease (AD) neurons, primarily in the cytoplasm.
- This cytoplasmic localization suggests a potential role for mitochondrial dysfunction in AD pathogenesis.
Purpose of the Study:
- To investigate mitochondrial abnormalities in Alzheimer's disease.
- To determine the relationship between mitochondrial abnormalities and oxidative damage markers (8-hydroxyguanosine and nitrotyrosine).
Main Methods:
- In situ hybridization for mitochondrial DNA (mtDNA).
- Immunocytochemistry for cytochrome oxidase.
- Morphometric analysis of electron micrographs from biopsy specimens.
Main Results:
- Neurons with increased oxidative damage in AD exhibit significantly higher levels of mtDNA and cytochrome oxidase.
- Elevated mtDNA and cytochrome oxidase are found in the neuronal cytoplasm and vacuoles.
- Morphometric analysis reveals a significant reduction in the number of mitochondria in AD neurons.
Conclusions:
- Mitochondrial abnormalities are closely associated with oxidative damage in Alzheimer's disease.
- The findings suggest an intimate and potentially early link between mitochondrial dysfunction and oxidative stress in AD pathogenesis.
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