Endothelial dysfunction and increased oxidative stress in mitochondrial diseases.
Pietro Minuz1, Cristiano Fava, Gaetano Vattemi
1Department of Medicine, Section of Internal Medicine, University of Verona, Verona, Italy. pietro.minuz@univr.it
Clinical Science (London, England : 1979)
|October 6, 2011
Summary
Mitochondrial diseases (MDs) cause endothelial dysfunction due to increased oxidative stress. Antioxidant vitamins temporarily improved vascular function in patients, suggesting oxidative stress contributes to this dysfunction.
Area of Science:
- Biochemistry
- Vascular Biology
- Mitochondrial Medicine
Background:
- Mitochondrial diseases (MDs) are characterized by impaired respiratory chain function and altered oxidative phosphorylation.
- Increased oxidative stress is implicated in the pathophysiology of various chronic conditions.
Purpose of the Study:
- To investigate the hypothesis that vascular endothelial function is impaired by increased oxidative stress in patients with MDs.
- To assess the effect of antioxidant supplementation on endothelial function in MDs.
Main Methods:
- Assessed endothelial function using flow-mediated vasodilation (FMD) in brachial and femoral arteries of 12 MD patients and controls.
- Measured urinary 8-iso-prostaglandin F2α (8-iso-PGF2α) as a marker of oxidative stress.
- Administered vitamin C and E supplementation, followed by a washout period, to evaluate treatment effects.
Main Results:
- FMD was significantly reduced in MD patients compared to controls, correlating with plasma lactate levels.
- Urinary 8-iso-PGF2α was elevated in MD patients and correlated with plasma lactate, with staining found in muscle biopsies.
- Antioxidant vitamin supplementation transiently restored FMD in MD patients, normalizing values compared to controls.
Conclusions:
- Increased oxidative stress contributes to endothelial dysfunction in patients with mitochondrial diseases.
- Targeting oxidative stress with antioxidants may offer a therapeutic avenue for managing vascular complications in MDs.
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