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Molybdenum has been found to be associated with metabolic disorders. However, the relationship between molybdenum and metabolic syndrome (MetS) is still unclear. A large case-control study was conducted in a Chinese population from the baseline of Ezhou-Shenzhen cohort. A total of 5356 subjects were included with 2678 MetS and 2678 controls matched by sex and age (±2 years). Medians (IQRs) of plasma molybdenum concentrations were 1.24 μg/L for MetS cases and 1.46 μg/L for controls. After adjustment for multiple covariates, the odds ratio (OR) and 95% confidence intervals (CIs) for MetS were 1.00 (reference), 0.71 (0.59-0.84), 0.56 (0.46-0.68), and 0.47 (0.39-0.58) across quartiles of plasma molybdenum, and per SD increment of log-transformed molybdenum was associated with a 23% lower risk of MetS. In the spline analysis, the risk of MetS and its components decreased steeply with increasing molybdenum and followed by a plateau when the cutoff point was observed around 2.0 μg/L. The dose-dependent relationship of molybdenum with MetS remained consistent when considering other essential elements in the Bayesian kernel machine regression (BKMR) model. In our study, higher plasma molybdenum was significantly associated with a lower risk of MetS, as well as its components, in a dose-response manner.

Cellular coenzymes including coenzyme A (CoA), acetyl coenzyme A (acetyl-CoA), coenzymes of redox reactions and of energy, and antioxidants mediate biochemical reactions fundamental to the functioning of all living cells. The redox coenzymes include NAD + (oxidized nicotinamide adenine dinucleotide), NADH (reduced nicotinamide adenine dinucleotide), NADP + (oxidized nicotinamide adenine dinucleotide phosphate), and NADPH (reduced nicotinamide adenine dinucleotide phosphate); the energy coenzymes include ATP (adenosine triphosphate), ADP (adenosine diphosphate), and AMP (adenosine monophosphate); and the antioxidants include GSSG (oxidized glutathione) and GSH (reduced glutathione). Their measurement is important to better understand cellular metabolism. Recent advances have pushed the limit of metabolite quantitation using NMR methods to an unprecedented level, which offer a new avenue for analysis of the coenzymes and antioxidants. Unlike the conventional enzyme assays, which need separate protocols for analysis, a simple 1D 1 H NMR experiment enables analysis of all these molecular species in one step. In this chapter, we describe protocols for their identification and quantitation in tissue and whole blood using NMR spectroscopy.

Conventional human blood metabolomics employs serum or plasma and provides a wealth of metabolic information therein. However, this approach lacks the ability to measure and evaluate important metabolites such as coenzymes and antioxidants that are present at high concentrations in red blood cells. As an important alternative to serum/plasma metabolomics, we show here that a simple 1 H NMR experiment can simultaneously measure coenzymes and antioxidants in extracts of whole human blood, in addition to the nearly 70 metabolites that were shown to be quantitated in serum/plasma recently [ Anal. Chem. 2015 , 87 , 706 - 715 ]. Coenzymes of redox reactions: oxidized/reduced nicotinamide adenine dinucleotide (NAD + and NADH) and nicotinamide adenine dinucleotide phosphate (NADP + and NADPH); coenzymes of energy including adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP); and antioxidants, the sum of oxidized and reduced glutathione (GSSG and GSH) can be measured with essentially no additional effort. A new method was developed for detecting many of these unstable species without affecting other blood/blood plasma metabolites. The identities of coenzymes and antioxidants in blood NMR spectra were established combining 1D/2D NMR techniques, chemical shift databases, pH measurements and, finally, spiking with authentic compounds. This is the first study to report identification of major coenzymes and antioxidants and quantify them, simultaneously, with the large pool of other metabolites in human blood using NMR spectroscopy. Considering that the levels of coenzymes and antioxidants represent a sensitive measure of cellular functions in health and numerous diseases, the NMR method presented here potentially opens a new chapter in the metabolomics of blood.

Background: A significant association between Zn and Se homeostasis exists. At the same time, data on the influence of zinc supplementation on selenium distribution in organs and tissues seem to be absent. Therefore, the primary objective of the current study is to investigate the influence of zinc asparaginate supplementation on zinc and selenium distribution and serum superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity in Wistar rats., Methods: 36 rats were used in the experiment. The duration of the experiment was 7 and 14 days in the first and second series, respectively. The rats in Group I were used as the control ones. Animals in Groups II and III daily obtained zinc asparaginate (ZnA) in the doses of 5 and 15 mg/kg weight, respectively. Zinc and selenium content in liver, kidneys, heart, muscle, serum and hair was assessed using inductively coupled plasma mass spectrometry. Serum SOD and GPx activity was analysed spectrophotometrically using Randox kits., Results: Intragastric administration of zinc asparaginate significantly increased liver, kidney, and serum zinc content without affecting skeletal and cardiac muscle levels. Zinc supplementation also stimulated selenium retention in the rats' organs. Moreover, a significant positive correlation between zinc and selenium content was observed. Finally, zinc asparaginate treatment has been shown to modulate serum GPx but not SOD activity., Conclusions: The obtained data indicate that zinc-induced increase in GPx activity may be mediated through modulation of selenium status. However, future studies are required to estimate the exact mechanisms of zinc and selenium interplay.

An open, randomized, four-phased crossover study using 4 mg of pitavastatin or 20 mg of atorvastatin was performed to compare their efficacy and safety, especially regarding plasma levels of coenzyme Q10 (CoQ10) in 19 Japanese patients with heterozygous familial hypercholesterolemia. Pitavastatin and atorvastatin caused significant and almost comparable reductions in serum levels of total cholesterol (-35.4 vs. -33.8%), low-density lipoprotein cholesterol (-42.8 vs. -40.7%), and triglyceride (-26.1 vs. -29.4%), and significantly increased serum levels of high-density lipoprotein cholesterol (12.1 vs. 11.4%). Under these conditions, plasma levels of CoQ10 were reduced by atorvastatin (-26.1%, P=0.0007) but not by pitavastatin (-7.7%, P=0.39), although no adverse events or abnormalities of liver and muscle enzyme were observed after either statin treatment. It remains to be seen whether the observed changes in CoQ10 levels are related to the long-term safety of this drug.

Background: The hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) are effective cholesterol lowering medications, however, statins may interfere with CoQ(10) biosynthesis. We examined the effect of statin therapy as well as nutritional supplements on plasma, cardiac and skeletal muscle concentrations of CoQ(10)., Methods: Forty patients with left ventricular dysfunction had fasting blood samples collected at baseline and following four weeks of supplementation (150mg/day of CoQ(10)). Cardiac and skeletal muscle biopsies were collected at the time of surgery and frozen in liquid nitrogen until analyzed for CoQ(10) levels by high performance liquid chromatography., Results: Nutrient supplementation significantly increased plasma [(1.8 (1.2, 2.7) vs 0.8 (0.6, 0.94) mug/ml plasma, median+IQR; p=0.001)] and cardiac tissue concentrations of CoQ(10) [(120.5 (76.5, 177.1) vs 87.3 (60.5, 110.8) nmol/g wet weight, p=0.04)]. No effect of supplementation was seen on samples of skeletal muscle from the chest wall. Statin therapy was not found to influence plasma, cardiac or chest wall levels of CoQ(10)., Conclusion: Nutrient supplementation significantly increased plasma and cardiac tissue levels of CoQ(10) but did not influence chest wall muscle concentrations. Statin therapy did not significantly influence tissue concentrations of CoQ(10). Longer term studies are needed to confirm this observation.

A UPLC-MS method for determining Coenzyme Q(10) (CoQ(10)) levels in rat serum was developed. CoQ(10) was quantitatively extracted into 2-propanol using a fast extraction procedure. The separation of CoQ(10) was performed on a Waters Acquity UPLCtrade mark BEH C(18) column (1.7 microm, 1.0 mm x 50 mm) with the mobile phase containing acetonitrile, 2-propanol, and formic acid (90:10:0.1) over 5 min. The sensitivity of this method allows for the quantitation of 50 ng/mL CoQ(10) in serum (S/N=10). The linearity of this method was found to be from 50 to 20,000 ng/mL. The precision was less than 10% (intra- and inter-day), and the average extraction recovery was between 90 and 105%. This procedure provides a precise, sensitive and direct assay method for the determination of CoQ(10) in rat serum after oral administration. This method could be applied to further pharmacokinetic studies of CoQ(10).

Endogenous coenzyme Q10 is an essential cofactor in the mitochondrial respiratory chain, a potent antioxidant, and a potential biomarker for systemic oxidative status. Evidence of oxidative stress was reported in individuals with trisomy 21. In this study, 14 children with trisomy 21 had significantly increased (P < 0.0001) plasma ubiquinone-10 (the oxidized component of coenzyme Q10) compared with 12 age- and sex-matched healthy children (historical controls). Also, the mean ratio of ubiquinol-10 (the biochemically reduced component):total coenzyme Q10 was significantly decreased (P < 0.0001). After 3 months of ubiquinol-10 supplementation (10 mg/kg/day) to 10 patients with trisomy 21, the mean ubiquinol-10:total coenzyme Q10 ratio increased significantly (P < 0.0001) above baseline values, and 80% of individual ratios were within normal range. No significant or unexpected adverse effects were reported by participants. To our knowledge, this is the first study to indicate that the pro-oxidant state in plasma of children with trisomy 21, as assessed by ubiquinol-10:total coenzyme Q10 ratio, may be normalized with ubiquinol-10 supplementation. Further studies are needed to determine whether correction of this oxidant imbalance improves clinical outcomes of children with trisomy 21.

Commercial coenzyme Q(10) (CoQ(10)) and alpha-tocopherol (vitamin E) formulations often show poor intestinal absorption. Delivery of CoQ(10) and vitamin E was enhanced when used with a new formulation, NanoSolve (Lipoid GmbH, Ludwigshafen, Germany), as shown by an open, comparative monocenter, crossover study of 24 volunteers. Plasma CoQ(10) and vitamin E were determined from predose until +14 hours. To compare bioavailability, corrected maximum concentration, time to reach maximum concentration, and area under the curve from 0 to 14 hours were assessed. The NanoSolve test formulation contained 100 mg of CoQ(10) and 120 mg of vitamin E. The pure substances in hard gelatin capsules served as the reference. Although identical amounts of CoQ(10) and vitamin E were administered, absolutely higher serum concentrations of the active ingredients were achieved by the NanoSolve formulation than by the pure materials in gelatin capsules. The bioavailability of CoQ(10) increased fivefold after administration of the NanoSolve formulation, and the bioavailability of vitamin E was enhanced 10-fold both compared to the pure substances.

The long-term efficacy and safety of HMG-CoA reductase inhibitors (statins) have been established in large multicenter trials. Inhibition of this enzyme, however, results in decreased synthesis of cholesterol and other products downstream of mevalonate, such as CoQ10 or dolichol. This was a randomized double-blind, placebo-controlled study that examined the effects of CoQ10 and placebo in hypercholesterolemic patients treated by atorvastatin. Eligible patients were given 10mg/day of atorvastatin for 16 weeks. Half of the patients (n=24) were supplemented with 100mg/day of CoQ10, while the other half (n=25) were given the placebo. Serum LDL-C levels in the CoQ10 group decreased by 43%, while in the placebo group by 49%. The HDL-C increment was more striking in the CoQ10 group than in the placebo group. All patients showed definite reductions of plasma CoQ10 levels in the placebo group, by 42%. All patients supplemented with CoQ10 showed striking increases in plasma CoQ10 by 127%. In conclusion atorvastatin definitely decreased plasma CoQ10 levels and supplementation with CoQ10 increased their levels. These changes in plasma CoQ10 levels showed no relation to the changes in serum AST, ALT and CK levels. Further studies are needed, however, for the evaluation of CoQ10 supplementation in statin therapy.

Myalgia is the most frequently reported adverse side effect associated with statin therapy and often necessitates reduction in dose, or the cessation of therapy, compromising cardiovascular risk management. One postulated mechanism for statin-related myalgia is mitochondrial dysfunction through the depletion of coenzyme Q(10), a key component of the mitochondrial electron transport chain. This pilot study evaluated the effect of coenzyme Q(10) supplementation on statin tolerance and myalgia in patients with previous statin-related myalgia. Forty-four patients were randomized to coenzyme Q(10) (200 mg/day) or placebo for 12 weeks in combination with upward dose titration of simvastatin from 10 mg/day, doubling every 4 weeks if tolerated to a maximum of 40 mg/day. Patients experiencing significant myalgia reduced their statin dose or discontinued treatment. Myalgia was assessed using a visual analogue scale. There was no difference between combined therapy and statin alone in the myalgia score change (median 6.0 [interquartile range 2.1 to 8.8] vs 2.3 [0 to 12.8], p = 0.63), in the number of patients tolerating simvastatin 40 mg/day (16 of 22 [73%] with coenzyme Q(10) vs 13 of 22 [59%] with placebo, p = 0.34), or in the number of patients remaining on therapy (16 of 22 [73%] with coenzyme Q(10) vs 18 of 22 [82%] with placebo, p = 0.47). In conclusion, coenzyme Q(10) supplementation did not improve statin tolerance or myalgia, although further studies are warranted.

We present a case of a patient with longstanding transfusion-dependent congenital dyserythropoietic anaemia (CDA) who developed cardiomyopathy despite iron chelation therapy. She presented with severe heart failure that responded poorly to conventional therapy, recovering only when therapy was augmented with metabolic agents including antioxidants and with increased iron chelation. The present case gives support to the concept of treating oxidatively induced heart failure with metabolic and antioxidant therapy. This therapy may have wider application in refractory heart failure and in the prevention of cardiomyopathy in patients receiving regular red cell transfusions who are at risk of transfusional haemosiderosis.

Objectives: We investigated the association of idiopathic sudden sensorineural hearing loss (ISSNHL) with coenzyme Q (CoQ) and cardiovascular risk factors., Study Design: A prospective study., Setting: Hospital center., Patients: Thirty Italian patients with ISSNHL and 60 healthy Italian subjects., Intervention: Diagnostic., Main Outcome Measures: Evaluation of serum CoQ levels and cardiovascular risk factors (total cholesterol, low-density lipoprotein [LDL], homocysteine [HCY]). The results were compared with variance analysis and Student's t test. Univariate and multivariate analysis were used to evaluate the association between ISSNHL and CoQ, total cholesterol, LDL, and HCY levels., Results: In our series, we found a significant association between ISSNHL and high total cholesterol (p < 0.05), high LDL (p = 0.021), and low CoQ (p < 0.05) levels. We did not find a significant association between ISSNHL and HCY levels. In the univariate analysis, low levels of CoQ, high levels of total cholesterol, and LDL were found to be significantly associated with ISSNHL. In the multivariate analysis, only high levels of total cholesterol and low levels of CoQ remained significantly associated with a high risk of sudden sensorineural hearing loss., Conclusion: The studies regarding the role of cardiovascular risk factors in ISSNHL are not conclusive. This is the first report regarding the association of ISSNHL and low serum levels of the antioxidant CoQ. Further studies are needed to investigate the role of antioxidants, including CoQ, in ISSNHL.

Dietary coenzyme Q(10) prolongs life span of rats fed on a PUFAn-6-enriched diet. Our aim was to analyze changes in the levels of plasma proteins of rats fed on a PUFAn-6 plus coenzyme Q(10)-based diet. This approach could give novel insights into the mechanisms of life span extension by dietary coenzyme Q(10) in the rat. Serum albumin, which decreases with aging in the rat, was significantly increased by coenzyme Q(10) supplementation both at 6 and 24 months. After depletion of the most abundant proteins by affinity chromatography, levels of less abundant plasma proteins were also studied by using 2D-electrophoresis and MALDI-TOF mass fingerprinting analysis. Our results have shown that lifelong dietary supplementation with coenzyme Q(10) induced significant decreases of plasma hemopexin, apolipoprotein H and inter-alpha-inhibitor H4P heavy chain (at both 6 and 24 months), preprohaptoglobin, fibrinogen gamma-chain precursor, and fetuin-like protein (at 6 months), and alpha-1-antitrypsin precursor and type II peroxiredoxin (at 24 months). On the other hand, coenzyme Q(10) supplementation resulted in significant increases of serine protease inhibitor 3, vitamin D-binding protein (at 6 months), and Apo A-I (at 24 months). Our results support a beneficial role of dietary coenzyme Q(10) decreasing oxidative stress and cardiovascular risk, and modulating inflammation during aging.

In this paper the authors review the relationship and the possible interaction between the HMG-CoA reductase inhibitors (statins) and the CoQ10 (ubiquinone) based on the current literature. The statins are widely used in the clinical practice. Inhibiting the synthesis of mevalonic acid they decrease the plasma cholesterol level. Since mevalonic acid is also required for ubiquinone synthesis statins could influence ubiquinone metabolism. Many studies confirmed the relationship between statin therapy and lower plasma ubiquinone level. Much less data are available about the tissue concentration changes of ubiquinone during statin therapy. The authors try to summarise the consequences of the interaction between statin therapy and ubiquinone metabolism.

Objective: 6R-5,6,7,8-tetrahydro-L-biopterin (6R-BH4) is a cofactor for endothelial nitric oxide synthase but also has antioxidant properties. Its stereo-isomer 6S-5,6,7,8-tetrahydro-L-biopterin (6S-BH4) and structurally similar pterin 6R,S-5,6,7,8-tetrahydro-D-neopterin (NH4) are also antioxidants but have no cofactor function. When endothelial nitric oxide synthase is 6R-BH4-deplete, it synthesizes superoxide rather than nitric oxide. Reduced nitric oxide bioavailability by interaction with reactive oxygen species is implicated in endothelial dysfunction (ED). 6R-BH4 corrects ED in animal models of ischemia reperfusion injury (IRI) and in patients with cardiovascular risks. It is uncertain whether the effect of exogenous 6R-BH4 on ED is through its cofactor or antioxidant action., Methods and Results: In healthy volunteers, forearm blood flow was measured by venous occlusion plethysmography during intra-arterial infusion of the endothelium-dependent vasodilator acetylcholine, or the endothelium-independent vasodilator glyceryl trinitrate, before and after IRI. IRI reduced plasma total antioxidant status (P=0.03) and impaired vasodilatation to acetylcholine (P=0.01), but not to glyceryl trinitrate (P=0.3). Intra-arterial infusion of 6R-BH4, 6S-BH4 and NH4 at approximately equimolar concentrations prevented IRI., Conclusion: IRI causes ED associated with increased oxidative stress that is prevented by 6R-BH4, 6S-BH4, and NH4, an effect mediated perhaps by an antioxidant rather than cofactor function. Regardless of mechanism, 6R-BH4, 6S-BH4, or NH4 may reduce tissue injury during clinical IRI syndromes.

The major coenzyme Q species in humans is the decaprenyl quinoid derivative coenzyme Q10 (CoQ10), and its measurement is somewhat challenging owing to its hydrophobicity and tendency to be oxidized. There are three major methods which are suited for analysis of CoQ10: HPLC-coupled UV or electrochemical detection, and tandem mass spectrometry. The techniques are discussed, and results of these applications to determine CoQ10 concentrations in various human fluids and tissues are summarized.

PureSorb-Q40 (water-soluble type CoQ10 powder, CoQ10 content is 40 w/w%; hereinafter referred to as P40) is reported in the single-dose human and rat studies to have a greater absorption rate and absorbed volume of CoQ10 even taken postprandially, than those of regular CoQ10, which is lipid-soluble and generally taken in the form of soft-gel capsules. Thus, it was anticipated that the serum CoQ10 level might be higher with P40 tablets than with soft-gel capsules, even for the same dose of CoQ10. In the present study, in order to confirm the safety and measure the serum CoQ10 level for the case of an excessive dose of P40, a double-blinded Placebo controlled comparative study was conducted on 46 healthy volunteers and they were randomly divided into two groups. The P40 tablets or placebo were repeatedly taken by the volunteers. As the result of the study, for the group of taking 2250 mg/d of P40 (that is, 900 mg/d of CoQ10) for 4 consecutive wk, the serum CoQ10 level peaked at 2 wk after the start of intake at 8.79 +/- 3.34 microg/mL, and at 4 wk, it was at the level of 8.33 +/- 4.04 microg/mL. At 2 wk from withdrawal of intake, the serum CoQ10 level decreased to 1.30 +/- 0.49 microg/mL. The serum CoQ10 levels at these three points were significantly higher than those of the first day of intake and the Placebo group, which had no significant change throughout the study. Furthermore, P40 intake did not cause any significant changes in symptoms or clinical laboratory results as assessed by physical, hematological, blood biochemical or urinalysis tests. Physician examinations also did not reveal any abnormalities. These results confirm that P40 is an extremely safe material and it can produce better absorption of CoQ10.

Plasma coenzyme Q10 (CoQ10) response to oral ingestion of various CoQ10 formulations was examined. Both total plasma CoQ10 and net increase over baseline CoQ10 concentrations show a gradual increase with increasing doses of CoQ10. Plasma CoQ10 concentrations plateau at a dose of 2400 mg using one specific chewable tablet formulation. The efficiency of absorption decreases as the dose increases. About 95% of circulating CoQ10 occurs as ubiquinol, with no appreciable change in the ratio following CoQ10 ingestion. Higher plasma CoQ10 concentrations are necessary to facilitate uptake by peripheral tissues and also the brain. Solubilized formulations of CoQ10 (both ubiquinone and ubiquinol) have superior bioavailability as evidenced by their enhanced plasma CoQ10 responses.

Coenzyme Q10 (CoQ10) is a lipid-soluble antioxidant and essential component of the mitochondrial electron transfer system in the body, and is in wide use as a functional food material and cosmetic raw material. However, as CoQ10 is extremely lipid-soluble, absorption by the body is not easy. In general, people use soft-gel capsules in which CoQ10 is suspended in oil, and take these capsules with food. PureSorb-Q40 (P40) was developed to improve CoQ10 processability and absorption when taken without food, and the present study compared the effects of food on absorption between P40 and conventional lipid-soluble CoQ10 in rats and humans. The results of a rat study showed higher uptake when P40 was administered in the fasting state or with food compared to lipid-soluble CoQ10. The results of a human study showed that uptake was favorable when P40 was administered in the fasting state, and even when administered postprandially, a significant difference was noted in uptake rate up to 6 h after intake and uptake volume up to 8 h after intake when compared to lipid-soluble CoQ10. These results show that any CoQ10 product using P40 can be quickly and reliably absorbed by the body regardless of dosage form or intake time.

Coenzyme Q10 (CoQ10) is used by the body as an endogenous antioxidant. This property combined with its essential function in mitochondrial energy production suggests that it may have therapeutic potential in cancer treatment. As part of the body's antioxidant defence against free radical production, CoQ10 concentrations may change during anti-cancer chemotherapy. Our study measured CoQ10 concentration in the plasma of 27 children with acute lymphoblastic leukaemia (ALL) at the time of diagnosis, during induction (protocol ALL-BFM 2000), and post induction treatment. The starting values were compared to the CoQ10 concentrations in 92 healthy children. The total CoQ10 concentration and its redox status were measured by HPLC using electrochemical detection and internal standardisation. While the CoQ10 concentration in the plasma of children with ALL was within a normal range at the time of diagnosis (0.99 +/- 0.41 pmol/microl), a drastic increase was observed during induction treatment (2.19 +/- 1.01 pmol/mul on day 33). This increase was accompanied by shift in the redox status in favour of the reduced form of CoQ10. The increase in CoQ10 concentration during induction treatment may be attributed to the activation of a natural antioxidative defence mechanism, endocrine influence on CoQ10 synthesis from steroid treatment, or a shift in CoQ10 from the damaged cells to the plasma after cell lysis.

Aim: We aimed to examine the effect of Coenzyme Q10 (CoQ10) supplementation on the exhaustive exercise-induced injury and oxidative stress in skeletal muscle and liver., Methods: Rats were divided into four groups: rest group [control (Con)-Rest; n = 6)], exercise group (Con-Ex; n = 6), rest group with CoQ10 supplement (CoQ10-Rest; n = 6), and exercise group with CoQ10 supplement (CoQ10-Ex; n = 6). The exercise groups were run on a treadmill until exhaustion. The CoQ10 supplemented groups received an oral administration of CoQ10 (300 mg kg(-1), 4 weeks). After 4 weeks, total CoQ concentration, creatine kinase (CK), glutamic-oxaloacetic transaminase (GOT), malondialdehyde (MDA), scavenging activity against reactive oxygen species [ROS; superoxide anions (O2*-) and hydroxyl radicals (HO*)] were measured., Results: Total CoQ concentration in plasma, slow-twitch muscles (soleus and gastronemius deep portion), and liver were significantly increased by CoQ10 supplementation. Plasma CK was significantly higher in Con-Ex compared with Con-Rest, whereas there was no difference between CoQ10-Rest and CoQ10-Ex. There were no significant differences in muscle MDA in each group. Plasma GOT and liver MDA in exercise groups were significantly higher than that of rest groups, but not significantly different between CoQ10 supplemented groups and control groups. CoQ10 supplementation was not able to favorably influence ROS scavenging activity in skeletal muscle and liver., Conclusions: These data indicated that CoQ10 supplementation increased total CoQ concentration in the slow-twitch muscles, and was useful for reducing exhaustive exercise-induced muscular injury by enhancing stabilization of muscle cell membrane.

The relative bioavailability of coenzyme Q10 (CoQ10) is markedly influenced by its delivery systems. The aim of this study was to compare four standard CoQ10 supplements available on the market with a novel solubilizate formulation of CoQ10 (Solu Q10). Pharmacokinetic parameters were assessed in 54 healthy volunteers after single and multiple intakes of 60 mg CoQ10 over a time period of 14 days. Solubilizates showed earlier flooding compared with oily dispersions and crystalline CoQ10, resulting in significantly elevated area under the curve between 0 and 4 h (P<0.01 solubilizates versus crystalline). The difference in the pharmacokinetic parameters of maximum plasma concentration, time to reach the peak plasma concentration and area under the curve between 0 and 12 h was not statistically significant between formulations. Long-term supplementation resulted in significantly higher plasma levels (P<0.01) for all formulations, with Solu Q10 performing best. Intracellular CoQ10 levels measured in buccal mucosa cells were increased (P<0.05) in response to supplementation when starting within the physiological range. In summary, solubilizates were clearly superior to oily dispersions and crystalline CoQ10 in their overall bioavailability, with the best absorption characteristics seen for the novel Solu Q10 solubilizate.

Statin therapy can reduce the biosynthesis of both cholesterol and coenzyme Q10 by blocking the common upstream mevalonate pathway. Coenzyme Q10 depletion has been speculated to play a potential role in statin-related adverse events, and withdrawal of statin is the choice in patients developing myotoxicity or liver toxicity. However, the effect of statin withdrawal on circulating levels of coenzyme Q10 remains unknown. Twenty-six patients with hypercholesterolemia received atorvastatin at 10 mg/day for 3 months. Serum lipid profiles and coenzyme Q10 were assessed before and immediately after 3 months and were also measured 2 and 3 days after the last day on the statin. After 3 months' atorvastatin therapy, serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and coenzyme Q10 (0.43 +/- 0.23 to 0.16 +/- 0.10 microg/mL) were all significantly reduced (all p<0.001). On day 2 after the last atorvastatin, the coenzyme Q10 level was significantly elevated (0.37 +/- 0.16 microg/mL) and maintained the same levels on day 3 (0.39 +/- 0.18 microg/mL) compared with those on month 3 (both p< 0.001), while TC and LDL-C did not significantly change within the same 3 days. These results suggest that statin inhibition of coenzyme Q10 synthesis is less strict than inhibition of cholesterol biosynthesis.

Unlabelled: The risk of cardio vascular disease (CVD) doubles after menopause. Plasma homocysteine (hCy) is a risk factor which is influenced by vitamins B12,B6 and folate. The present study was conducted to examine the relationship of plasma hCy to the three vitamins and other contributing variables in early natural menopause., Methods: Participants were healthy, non smoking Caucasian women 3 to 5 years postmenopausal (n = 26) or premenopausal between 30 and 45 y(n = 30). Anthropometric data, dietary records and plasma concentrations of hCy, vitamin B6, vitamin B12 and folate were obtained., Results: The nutritional status of vitamins B6, B12 and folate as measured by dietary intake and blood concentrations was adequate in both groups. Mean fasting plasma total (t) hCy concentration of postmenopausal group was 2-fold higher than the value found for control group (P < 0.0001) without oral methionine loading. The difference between the two groups remained highly significant after adjustment for confounding variables by multivariate analysis, suggesting that the effect of estrogen deficiency was direct., Conclusion: In addition to the loss of the protective effects of estrogen on their cardiovascular physiology and lipid metabolism, postmenopausal women are exposed to higher plasma hCy concentrations and deleterious cardiovascular effects. The exact mechanism is not known but does not seem to be related to coenzyme deficiency.

The present work investigated the activity of Cu/Zn superoxide dismutase enzyme (SOD) in red blood cells and glutathione peroxidase enzyme (GPx) in whole blood by spectrophotometric methods. Plasma levels of the cofactors copper and zinc and whole-blood selenium were evaluated using atomic absorption spectrophotometer. The study included a population of 18 Down's syndrome (DS) patients with complete trisomy 21 (group 1), translocations (group 2), and mosaicism (group 3), and their 15 matched controls. The purpose of this work was to study the gene dosage effect of SOD and its consequence on GPx enzyme and the various cofactors, and to find out correlations with developmental fields. Our results showed that in the population with complete trisomy 21 and translocations, SOD and GPx activities were increased, whereas in cases with mosaicism, the enzymes activities were within normal limits. Plasma copper concentrations were increased, whereas whole-blood selenium concentrations were significantly decreased in the three DS groups. Plasma zinc levels were within normal in all patients. We concluded that changes in trace elements and enzyme activities were not related to age or sex. Also, there was no correlation between the enzyme levels and the developmental activities. Our results are useful tools for identifying nutritional status and guiding antioxidant intervention.

We have developed a new automated method for the determination of malate dehydrogenase (MDH) isoenzymes in serum employing guanidine hydrochloride. Our proposed method showed good reproducibility; within-run precision coefficient of variations (CVs) were less than 2.5 (mean 13.6-42.9 U/L) for total MDH (T-MDH) and less than 6.7% (mean 6.3-23.5 U/L) for mitochondrial MDH (m-MDH) (n = 10). The upper detection limit of the proposed method exhibited good linearity up to 1,000 U/L for both T-MDH and m-MDH. In the proposed m-MDH reagent, the presence of up to 2,000 U/L of cytosolic MDH(c-MDH) activity had no effect on the outcome of m-MDH assay. Results of our proposed method (y) correlated well with those of the electrophoretic method (x) giving the regression equation: y = 1.46 x + 6.87 (N = 30); r = 0.99. Normal concentrations of various anticoagulants and bilirubin did not affect the assay results. Both ascorbic acid and glucose exhibited a slight positive interference with the proposed assay. Clinically, we found that m-MDH activity in serum had greater diagnostic predictive value than T-MDH activity for judging successful outcome of reperfusion therapy; the prognosis was poor when the m-MDH/T-MDH ratio was greater than 20%.

A method for creating a reference model in the quantitative assay of specific clotting factor activities is described. This method incorporates the use of a piecewise function with two component polynomials. This function allows more accurate representation of the global coagulation reaction, a sequential activation of multiple serine protease enzymes and cofactors, leading to improvements over traditional methods in range, accuracy, precision and robustness in reported activity levels. Clotting factor assay results using this method are compared with traditional and other candidate methods.

PQQ, also called methoxatin, has been isolated from guinea-pig neutrophils. The organic cations diphenyleneiodonium (DPI) and diphenyliodonium (BPI) and the aromatic o-diamine 4,5-dimethylphenylenediamine (DIMPDA) sequester synthetic PQQ and inhibit its redox-cycling activity in a model system. Standards were made of adducts of tritiated PQQ with unlabeled DIMPDA and of unlabeled PQQ with tritiated DPI or DIMPDA. PQQ adducts were isolated from guinea-pig neutrophils with each of the tritiated inhibitors. They were separated and defined by high-performance liquid chromatography (HPLC). Tiron, a disodium benzene disulphonic acid, broke the DPI-PQQ adduct isolated from neutrophils and released free PQQ. Both DPI and DIMPDA, as well as BPI, blocked O2.- release by stimulated neutrophils. The blockade exerted by these inhibitors was released by the addition of PQQ to the cell suspensions. The data demonstrate the presence of PQQ in guinea-pig neutrophils and suggest that it has a possible role, direct or indirect, in the O2.(-)-producing respiratory burst.

Phosphatidylethanolamine:dolichol acyltransferase (PEDAT), an enzyme previously partially purified and characterized in rat liver [Sindelar, P., Chojnacki, T., & Valtersson, C. (1992) J. Biol. Chem. 267, 20594-20599], is here purified to homogeneity from a heparin perfusate of rat liver and is shown to be identical to hepatic lipase. However, in contrast to triglyceride hydrolysis by hepatic lipase, the PEDAT activity is strongly dependent on a heat-stable plasma cofactor. This cofactor stimulates the activity up to 15-fold and shifts the pH optimum for the reaction from 8.5 to 7.5. Upon gel filtration on Bio-Gel A-1.5, the factor is heterogeneously distributed, with a major peak at 220 kDa. The dolichol-acylating activity can also be detected in rat adrenals and ovaries, and evidence is presented that the PEDAT assay shows a higher degree of specificity for hepatic lipase than the standard assay with triolein-gum arabic emulsion in 1 M NaCl.

Increase of vitamin B6 derivatives by 36% in liver tissue, decrease in content of thiamine by 20%, of ascorbic acid--by 35%, of oxidized nicotinamide coenzymes--by 27%, simultaneously with a decrease in excretion of 1-methyl nicotinamide and 4-pyridoxic acid with urine were observed in rats with alimentary deficiency in riboflavin as compared with the animals kept on a ration containing 1/3 of the vitamin physiological requirements. The same regularities were detected in adult persons and children examined for consumption of vitamins: a decrease in excretion of 4-pyridoxic acid and 1-methyl nicotinamide with urine, slight decrease in content of pyridoxal coenzymes in blood plasma and of nicotinamide coenzymes in erythrocytes were observed in children with deficiency in riboflavin close to deficiency of corresponding enzymes in food ration as compared with normal level of vitamin consumption. This suggests that evaluation of pyridoxine and/or niacin deficiency in food ration should be related with the rate of riboflavin consumption.

In 35 children of 9-13 years old with insulin-dependent diabetes mellitus distinct alterations in metabolism of vitamin B2 were detected, which were manifested as elevated rate of riboflavin excretion with urine and a decrease in the vitamin content in erythrocytes, as 1.5-fold increase in activity of erythrocyte glutathione reductase and augmented affinity of erythrocyte glutathione reductase to exogenous FAD. Alterations in metabolism of riboflavin did not involve the vitamin deficiency as shown by analysis of vitamins B6 and PP (4-pyridoxic acid and I-methyl nicotinamide, respectively) excretion with urine as well as by study of the coenzymes content in blood of healthy and sick children with various rates of riboflavin consumption. Rates of 4-pyridoxic acid and I-methyl nicotinamide excretion with urine were similar both in healthy children of 9-13 years and in children of this age with diabetes mellitus. The data obtained suggest that rates of riboflavin consumption in patients with diabetes mellitus differed from those of healthy persons; these reasons should be taken into consideration in evaluation of vitamins B2 consumption in patients with diabetes mellitus.

A detailed procedure for the assay of free pyrroloquinoline quinone (PQQ) in human and rat samples by gas chromatography/mass spectrometry (GC/MS) has been established with stable-isotopic PQQ as internal standard. PQQ was extracted from the samples, after addition of the internal standard, with butanol under acid conditions and with Sep-Pak C18 cartridges. After derivatization of PQQ with phenyltrimethylammonium hydroxide, molecular peaks at m/z 448 and 462 were used for detection of PQQ and [U-13C]PQQ by selected ion monitoring, respectively. Trace amounts of free PQQ were detected in eight organs, plasma and urine of the human, and in three organs of the rat. The PQQ level was highest in the human spleen (5.9 +/- 3.4 ng/g tissue, followed by the pancreas and lung, and it was below detection limits for human brain and heart. Trace levels of PQQ were also found in rat small intestine, liver and testis. Our data are far below those measured by the redox cycling method of Gallop's group for human plasma, adrenal and urine.

The determination of ammonia in plasma, using glutamate dehydrogenase, is complicated by non-specific oxidation of the coenzyme, promoted by components of the sample matrix. Measurements performed with appropriate plasma blanks show that 2'-phosphorylated coenzymes (NADPH, deamino-NADPH) are much less oxidized than NADH. By adding lactate dehydrogenase, NADH oxidation by endogenous pyruvate can be completed within a short time. Considerable consumption of coenzyme occurs, however, and endogenous L-alanine aminotransferase also represents a possible source of interference. The results of ammonia determinations using deamino-NADPH (y) or NADPH (x) were identical (a = 0.0 mumol/l, b = 1.00; r = 0.996, n = 62). With NADH as the coenzyme, the method displays adequate specificity only at high sample dilution, e.g. in the measurement of urea after conversion to ammonia.

The activities of the red blood cell enzymes transketolase, glutathione reductase, and glutamic oxaloacetate transaminase were measured with and without in vitro addition of their respective coenzyme components thiamine, riboflavin, and pyridoxine in a group of patients with neurological disorders which may have been caused by malnutrition, intestinal malabsorption, hepatic failure or neoplasms arising outside the nervous system. The incidence of thiamine deficiency was 31%, of riboflavin deficiency 22% and of pyridoxine deficiency 6%. Alcoholics in particular suffered from deficiencies of vitamin B 1, and B 2. There was a correlation of vitamin B 1 and B 2 deficiency and signs of a cerebellar and/or brainstem lesion. The most frequent symptoms in this connection were gait disturbances and oculomotor signs like spontaneous and gaze nystagmus, disturbed eye tracking, diminished optokinetic nystagmus, decreased ability to suppress vestibular nystagmus by fixation. These signs hardly ever occurred in alcoholic patients who showed no deficiency of vitamin B 1, B 2 or B 6. Whenever they do appear, a vitamin B supplementation has to be performed in order to prevent the manifestation of Wernicke's encephalopathy, cerebral or cerebellar atrophy. Alcoholics showed the same incidence of polyneuropathy, whether they suffered from a deficiency of B vitamins or not. Deficiencies of vitamin B 1, B 2 or B 6 were also found in patients with intestinal malabsorption and polyneuropathy, diabetic polyneuropathy, optic atrophy, myelopathy and cerebellar ataxia of unknown etiology, neurological manifestations of neoplasms arising outside the nervous system, B 12 myeloencephalopathy and Thévenard's syndrome.

Both soluble and particulate forms of human platelet guanylate cyclase were found to be sensitive to sub-micromolar concentrations of free Ca2+; soluble enzyme activity increased as Ca2+ was increased from 10 nM to 1 microM; particulate enzyme activity showed a biphasic response to Ca2+, with maximal enzyme activity between 1 and 10 nM free Ca2+ and inhibition occurring at higher Ca2+ concentrations. Neither Ca2+-sensitivity appeared to be calmodulin-dependent.

Adaptation of coenzyme stimulation assays for the nutritional assessment of thiamine, riboflavin and pyridoxine on the Cobas Bio centrifugal analyser are described. Whole blood was collected into acid-citrate dextrose, which preserves the erythrocytes, prior to assay for several days. Washed erythrocytes stored at -70 degrees C and subsequently thawed, showed altered enzyme activities. The methods offer improved precision over existing procedures and take advantage of the high throughput capabilities of the instrumentation.