ubiquinol and Coronary-Disease

Topics: Anticarcinogenic Agents; Antioxidants; Coronary Disease; Diet; Flavonoids; Humans; Neoplasms; Ubiquinone; Vitamins

A double-blinded, placebo-controlled cross-over trial was carried out with 27 hypercholesterolemic men with coronary heart disease. During the 6-week treatment period lovastatin (60 mg/day) decreased fasting serum LDL cholesterol by 45%, LDL phosphorus by 38% and apoB by 33%. Ubiquinol content diminished by 13% as measured per LDL phosphorus. When LDL was oxidized ex vivo with AMVN both LDL ubiquinol and alpha-tocopherol were exhausted faster after lovastatin treatment compared to placebo, by 24% (P < 0.005) and 36% (P < 0.0001), respectively. Lag time in copper-induced oxidation of LDL decreased by 7% (P < 0.01). This suggests diminished antioxidant-dependent resistance of LDL to the early phase of oxidative stress.

Topics: Adult; Aged; Anticholesteremic Agents; Antioxidants; Apolipoproteins A; Apolipoproteins B; Cholesterol; Cholesterol, LDL; Copper; Coronary Disease; Cross-Over Studies; Double-Blind Method; Humans; Hypercholesterolemia; Lovastatin; Male; Middle Aged; Oxidation-Reduction; Triglycerides; Ubiquinone; Vitamin E

Ubiquinol-10 and ubiquinone-10 were measured in plasma of patients with several pathologies known to be associated with increased oxidative stress. Plasma ubiquinol-10, expressed as a percentage of total ubiquinol-10 + ubiquinone-10, was found to be significantly lower in hyperlipidaemic patients and in patients with liver diseases than in age-matched control subjects. In contrast, no decrease in ubiquinol-10 was detected in plasma of patients with coronary heart disease and Alzheimer's disease. Except for ubiquinol-10, no other lipophilic antioxidant was found to be decreased in patients with liver diseases. These data suggest that the level of ubiquinol-10 in human plasma may serve as a marker for liver dysfunction, reflecting its diminished reduction by the liver rather than increased consumption by oxidants.

Topics: Adult; Aged; Alzheimer Disease; Biomarkers; Cholesterol; Coronary Disease; Humans; Hyperlipidemias; Liver Diseases; Middle Aged; Models, Biological; Oxidative Stress; Reference Values; Reproducibility of Results; Triglycerides; Ubiquinone

The purpose of the study was to investigate changes in serum ubiquinol/ubiquinone ratio with copper ion induced oxidative stress, and to assess the ubiquinol/ubiquinone ratio as marker of in vivo oxidative stress in patients with coronary artery disease (CAD). Plasma ubiquinol, ubiquinone, vitamin E (alpha-tocopherol) and total cholesterol (TC) concentrations were measured in 40 patients with angiographically confirmed coronary artery disease and 100 apparently healthy controls. The mean (SD) ubiquinol/ubiquinone ratio of 26.5 (7.5) of the CAD patients was significantly lower than the mean ratio of 30.2 (8.8) of the controls (p = 0.02). Our results indicate that the ubiquinol/ubiquinone ratio is a sensitive marker of oxidative stress and that an altered ubiquinol/ubiquinone ratio is the first sign of lipoprotein exposure to oxidative stress. The altered ratio in CAD patients cannot be explained by differences in plasma vitamin E levels. The vitamin E concentrations were in fact significantly higher in CAD patients, and did not appear to protect the ubiquinol from increased oxidation due to free radical reactions. These results may indicate that circulating lipoproteins of CAD patients are more exposed to, or are more susceptible to, free radical reactions compared with apparently healthy controls.

Topics: Adult; Aged; Biomarkers; Copper; Coronary Disease; Enzyme Inhibitors; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Lipoproteins; Male; Middle Aged; Oxidation-Reduction; Oxidative Stress; Ubiquinone; Vitamin E

Ubiquinol-10, the reduced form of ubiquinone-10 (coenzyme Q10), is a potent lipophilic antioxidant present in nearly all human tissues. The exceptional oxidative lability of ubiquinol-10 implies that it may represent a sensitive index of oxidative stress. The present study was undertaken to assess the hypothesis that the level of ubiquinol-10 in human plasma can discriminate between healthy subjects and patients who are expected to be subjected to an increased oxidative stress in vivo. Using a newly developed method, we measured plasma ubiquinol-10 in 38 hyperlipidaemic patients with and without further complications, such as coronary heart disease, hypertension, or liver disease, and in 30 healthy subjects. The oxidizability of plasma samples obtained from hyperlipidaemic patients was found to be increased in comparison with control subjects, suggesting that the patients were subjected to a higher oxidative stress in vivo than the controls. Plasma ubiquinol-10, expressed as a percentage of total ubiquinol-10 + ubiquinone-10 or normalized to plasma lipids, was lower in the patients than in controls (P = 0.001 and 0.008, respectively). The proportion of ubiquinol-10 decreased in the order young controls > aged controls > hyperlipidaemic patients without complications > hyperlipidaemic patients with complications (P = 0.003). A negative correlation was found between the proportion of ubiquinol-10 and plasma triglycerides. The hyperlipidaemic patients with hypertension had a lower proportion of ubiquinol-10 than subjects without. When the study population was divided into smokers and non-smokers, plasma ubiquinol-10 was found to be reduced amongst smokers, independently of whether it was expressed as a percentage of total ubiquinol-10 + ubiquinone-10 (P = 0.006) or normalized to plasma lipids (P = 0.009). These data suggest that the level of ubiquinol-10 in human plasma may represent a sensitive index of oxidative stress in vivo especially indicative of early oxidative damage. Measuring plasma ubiquinol-10 can be proposed as a practical approach to assess oxidative stress in humans.

Topics: Adult; Alcohol Drinking; Amidines; Antidotes; Body Mass Index; Coronary Disease; Female; Humans; Hyperlipidemias; Hypertension; Lipid Peroxidation; Lipoxygenase; Liver Diseases; Male; Middle Aged; Oxidation-Reduction; Oxidative Stress; Regression Analysis; Risk Factors; Smoking; Spectrophotometry; Triglycerides; Ubiquinone

Oxidative modifications of blood serum in humans with and without coronary artery disease were investigated. Four parameters were analyzed: the intensity of serum fluorescence, which is indicative of the content of lipofuscine-like lipid peroxidation products; the content of thiobarbituric acid-reactive substances; the lag-phase of serum oxidation by azo-compounds; and the content of lipophilic natural antioxidants--alpha-tocopherol, beta-carotene and ubiquinol-9(10). It was found that coronary artery disease resulted in a significant increase of serum fluorescence and the content of TBARS. The atherogenic disorders in humans with coronary artery disease drastically decreased the lag-phase of serum oxidation in the presence of 2,2'-azo-bis-(2-amidinopropane) dihydrochloride. The oxidative modifications of serum were in close correlation with the balance of natural lipophilic antioxidants in blood serum, i.e. alpha-tocopherol, ubiquinols and beta-carotene. The contents of all antioxidants tested in serum were significantly decreased in patients with coronary artery disease.

Topics: Aged; Amidines; Analysis of Variance; beta Carotene; Biomarkers; Coronary Disease; Female; Free Radicals; Humans; Lipid Peroxidation; Lipid Peroxides; Male; Middle Aged; Oxidation-Reduction; Thiobarbituric Acid Reactive Substances; Ubiquinone; Vitamin E