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Updated: Jan 29, 2026
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Analysis of Brain Mitochondria Using Serial Block-Face Scanning Electron Microscopy
Published on: July 9, 2016
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Methylene blue does not bypass Complex III antimycin block in mouse brain mitochondria
Artem P Gureev1, Ekaterina A Shaforostova1, Vasily N Popov1,2
1Department of Genetics, Cytology and Bioengineering, Voronezh State University, Russia.
FEBS Letters
|February 9, 2019
Summary
Methylene blue (MB) may not effectively treat Alzheimer's disease by restoring mitochondrial function. Studies show MB fails to bypass Complex III inhibition in the electron transfer chain, suggesting limited therapeutic potential for certain mitochondrial disorders.
Area of Science:
- Biochemistry
- Neuroscience
- Pharmacology
Background:
- Mitochondrial dysfunction is implicated in Alzheimer's disease.
- Methylene blue (MB) is investigated as a prodrug to treat these dysfunctions.
- MB's proposed mechanism involves acting as a redox mediator in the electron transfer chain (ETC).
Purpose of the Study:
- To investigate the efficacy of Methylene blue (MB) in restoring mitochondrial function in the context of Alzheimer's disease.
- To elucidate the specific mechanism of MB's action within the mitochondrial electron transfer chain.
Main Methods:
- Experiments were conducted using mouse brain mitochondria.
- Mitochondrial membrane potential and respiration were measured.
- Inhibition was induced using antimycin, a known Complex III inhibitor.
- Hydrogen peroxide (H2O2) generation was assessed.
Main Results:
- Methylene blue (MB) failed to restore mitochondrial membrane potential and respiration inhibited by antimycin.
- Antimycin was found to inhibit MB-induced hydrogen peroxide (H2O2) generation.
- Electron acceptor for MB was identified as the Qo ubiquinol-binding site of Complex III.
Conclusions:
- Methylene blue (MB) may not be effective in treating mitochondrial dysfunctions caused by Complex III inhibition.
- The therapeutic potential of MB-based drugs for Alzheimer's disease might be limited in cases involving Complex III.
- Further research is needed to understand MB's precise role in ETC and its applicability in neurodegenerative diseases.
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