Mass Spectrometry-Based Metabolic Fingerprinting Contributes to Unveil the Role of RSUME in Renal Cell Carcinoma Cell Metabolism.

Clear cell renal cell carcinoma (ccRCC) is a heterogeneous disease with 50-80% patients exhibiting mutations in the von Hippel-Lindau (VHL) gene. RSUME (RWD domain (termed after three major RWD-containing proteins: RING finger-containing proteins, WD-repeat-containing proteins, and yeast DEAD (DEXD)-like helicases)-containing protein small ubiquitin-related modifier (SUMO) enhancer) acts as a negative regulator of VHL function in normoxia. A discovery-based metabolomics approach was developed by means of ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (MS) for fingerprinting the endometabolome of a human ccRCC cell line 786-O and three other transformed cell systems (n = 102) with different expressions of RSUME and VHL. Cross-validated orthogonal projection to latent structures discriminant analysis models were built on positive, negative, and a combination of positive- and negative-ion mode MS data sets. Discriminant feature panels selected by an iterative multivariate classification allowed differentiating cells with different expressions of RSUME and VHL. Fifteen identified discriminant metabolites with level 1, including glutathione, butyrylcarnitine, and acetylcarnitine, contributed to understand the role of RSUME in ccRCC. Altered pathways associated with the RSUME expression were validated by biological and bioinformatics analyses. Combined results showed that in the absence of VHL, RSUME is involved in the downregulation of the antioxidant defense system, whereas in the presence of VHL, it acts in rerouting energy-related pathways, negatively modulating the lipid utilization, and positively modulating the fatty acid synthesis, which may promote deposition in droplets.

Urban air pollution induces alterations in redox metabolism and mitochondrial dysfunction in mice brain cortex.

Previous reports indicate that the central nervous system (CNS) is a target of air pollution, causing tissue damage and functional alterations. Oxidative stress and neuroinflammation have been pointed out as possible mechanisms mediating these effects. The aim of this work was to study the chronic effects of urban air pollution on mice brain cortex, focusing on oxidative stress markers, and mitochondrial function. Male 8-week-old BALB/c mice were exposed to filtered air (FA, control) or urban air (UA) inside whole-body exposure chambers, located in a highly polluted area of Buenos Aires city, for up to 4 weeks. Glutathione levels, assessed as GSH/GSSG ratio, were decreased after 1 and 2 weeks of exposure to UA (45% and 25% respectively vs. FA; p < 0.05). A 38% increase in lipid peroxidation was found after 1 week of UA exposure (p < 0.05). Regarding protein oxidation, carbonyl content was significantly increased at week 2 in UA-exposed mice, compared to FA-group, and an even higher increment was found after 4 weeks of exposure (week 2: 40% p < 0.05, week 4: 54% p < 0.001). NADPH oxidase (NOX) and glutathione peroxidase (GPx) activities were augmented at all the studied time points, while superoxide dismutase (Cu,Zn-SOD cytosolic isoform) and glutathione reductase (GR) activities were increased only after 4 weeks of UA exposure (p < 0.05). The increased NOX activity was accompanied with higher expression levels of NOX2 regulatory subunit p47phox, and NOX4 (p < 0.05). Also, UA mice showed impaired mitochondrial function due to a 50% reduction in O2 consumption in active state respiration (p < 0.05), a 29% decrease in mitochondrial inner membrane potential (p < 0.05), a 65% decrease in ATP production rate (p < 0.01) and a 30% increase in H2O2 production (p < 0.01). Moreover, respiratory complexes I-III and II-III activities were decreased in UA group (30% and 36% respectively vs. FA; p < 0.05). UA exposed mice showed alterations in mitochondrial function, increased oxidant production evidenced by NOX activation, macromolecules damage and the onset of the enzymatic antioxidant system. These data indicate that oxidative stress and impaired mitochondrial function may play a key role in CNS damage mechanisms triggered by air pollution.

NADPH oxidase and mitochondria are relevant sources of superoxide anion in the oxinflammatory response of macrophages exposed to airborne particulate matter.

Exposure to ambient air particulate matter (PM) is associated with increased cardiorespiratory morbidity and mortality. In this context, alveolar macrophages exhibit proinflammatory and oxidative responses as a result of the clearance of particles, thus contributing to lung injury. However, the mechanisms linking these pathways are not completely clarified. Therefore, the oxinflammation phenomenon was studied in RAW 264.7 macrophages exposed to Residual Oil Fly Ash (ROFA), a PM surrogate rich in transition metals. While cell viability was not compromised under the experimental conditions, a proinflammatory phenotype was observed in cells incubated with ROFA 100 µg/mL, characterized by increased levels of TNF-α and NO production, together with PM uptake. This inflammatory response seems to precede alterations in redox metabolism, characterized by augmented levels of H2O2, diminished GSH/GSSG ratio, and increased SOD activity. This scenario resulted in increased oxidative damage to phospholipids. Moreover, alterations in mitochondrial respiration were observed following ROFA incubation, such as diminished coupling efficiency and spare respiratory capacity, together with augmented proton leak. These findings were accompanied by a decrease in mitochondrial membrane potential. Finally, NADPH oxidase (NOX) and mitochondria were identified as the main sources of superoxide anion () in our model. These results indicate that PM exposure induces direct activation of macrophages, leading to inflammation and increased reactive oxygen species production through NOX and mitochondria, which impairs antioxidant defense and may cause mitochondrial dysfunction.

Urban air pollution induces redox imbalance and epithelium hyperplasia in mice cornea.

The aim of the study was to evaluate the time course of the effects of urban air pollutants on the ocular surface, focusing on the morphological changes, the redox balance, and the inflammatory response of the cornea. 8-week-old mice were exposed to urban or filtered air (UA-group and FA-group, respectively) in exposure chambers for 1, 2, 4, and 12 weeks. After each time, the eyes were enucleated and the corneas were isolated for biochemical analysis. UA-group corneas exhibited a continuous increase in NADPH oxidase-4 levels throughout the exposure time, suggesting an increased production of reactive oxygen species (ROS). After 1 week, an early adaptive response to ROS was observed as an increase in antioxidant enzymes. After 4 weeks, the enzymatic antioxidants were decreased, meanwhile an increase of the glutathione was shown, as a later compensatory antioxidant response. However, redox imbalance took place, evidenced by the increased oxidized proteins, which persisted up to 12 weeks. At this time point, corneal epithelium hyperplasia was also observed. The inflammatory response was modulated by the increase in IL-10 levels after 1 week, which early regulates the release of TNF-α and IL-6. These results suggest that air pollution alters the ocular surface, supported by the observed cellular hyperplasia. The redox imbalance and the inflammatory response modulated by IL-10 play a key role in the response triggered by air pollutants on the cornea. Taking into account this time course study, the ocular surface should also be considered as a relevant target of urban air pollutants.

High-fat diet abolishes the cardioprotective effects of ischemic postconditioning in murine models despite increased thioredoxin-1 levels.

Ischemic postconditioning (PostC) reduces infarct size in healthy experimental models. However, if protective effects of PostC are abolished during early stages of atherosclerotic and if this is related with a disbalance in mitochondrial energetics and alterations in thioredoxin-1 (Trx1) is still unknown. The objectives were to generate a murine high-fat diet (HFD)-fed model that developed in a phenotype consistent with early stages of atherosclerosis to then evaluate whether HFD exposure increased oxidative stress and consequently abolished the cardioprotection conferred by PostC. We used C57/BL6 mice fed with control diet (CD) or HFD for 12 weeks. Isolated mice hearts were subjected to 30 min of ischemia and 120 min of reperfusion (I/R group). For PostC group, after ischemia, six cycles of reperfusion/ischemia were performed (10 s per cycle) at the onset of reperfusion. In CD group, the PostC reduced infarct size (CD-I/R: 52.14 ± 2.8 vs. CD-PostC: 36.58 ± 1.8, P < 0.05) and increased phosphorylation of GSK3ß (CD-PostC: 2.341 ± 1.03 vs. CD-Baseline: 0.923 ± 0.41 AUOD, P < 0.05), and this cardioprotection was abolished in HFD-exposed mice. HFD increased hydrogen peroxide levels, produced a shift towards an oxidized intracellular environment (GSSG/GSH2), and increased Trx1 expression with higher fractions of oxidized protein. State 3 mitochondrial oxygen consumption in basal conditions decreased 24% in HFD-exposed mice and PostC improved state 3 values only in CD mice. Cellular redox state and mitochondrial bioenergetics were altered in HFD-exposed mice. We demonstrated that alterations in redox state at early stages of atherosclerosis abolished cardioprotective mechanisms, such as those induced by PostC, even with increased Trx1 levels.

A novel non-invasive sampling method using buccal mucosa cells for determination of coenzyme Q10.

Coenzyme Q10 (CoQ10) is an important cofactor in the mitochondrial respiratory chain and a potent endogenous antioxidant. CoQ10 deficiency is often associated with numerous diseases, and patients can benefit from CoQ10 supplementation, being more effective when diagnosed and treated early. Due to the increased interest in CoQ10 deficiency, several methods for CoQ10 analysis from plasmatic, muscular, fibroblast, and platelet matrices have been developed. These sampling techniques are not only highly invasive but also too traumatic for periodic clinical monitoring. In the present work, we describe the development and validation of a novel non-invasive sampling method for quantification of CoQ10 in buccal mucosa cells (BMCs) by microHPLC. This method is suitable for using in a routine laboratory and useful for sampling patients in pediatry. CoQ10 correlation was demonstrated between BMCs and plasma levels (Spearman r, 0.4540; p < 0.001). The proposed method is amenable to be applied in the post treatment monitoring, especially in pediatric patients as a non-invasive sample collection. More studies are needed to assess whether this determination could be used for diagnosis and if this matrix could replace the traditional ones.

Coenzyme Q in pregnant women and rats with intrahepatic cholestasis.

BACKGROUND & AIMS: Intrahepatic cholestasis of pregnancy is a high-risk liver disease given the eventual deleterious consequences that may occur in the foetus. It is accepted that the abnormal accumulation of hydrophobic bile acids in maternal serum are responsible for the disease development. Hydrophobic bile acids induce oxidative stress and apoptosis leading to the damage of the hepatic parenchyma and eventually extrahepatic tissues. As coenzyme Q (CoQ) is considered an early marker of oxidative stress in this study, we sought to assess CoQ levels, bile acid profile and oxidative stress status in intrahepatic cholestasis. METHODS: CoQ, vitamin E and malondialdehyde were measured in plasma and/or tissues by HPLC-UV method whereas serum bile acids by capillary electrophoresis in rats with ethinyl estradiol-induced cholestasis and women with pregnancy cholestasis. RESULTS: CoQ and vitamin E plasma levels were diminished in both rats and women with intrahepatic cholestasis. Furthermore, reduced CoQ was also found in muscle and brain of cholestatic rats but no changes were observed in heart or liver. In addition, a positive correlation between CoQ and ursodeoxycholic/lithocholic acid ratio was found in intrahepatic cholestasis suggesting that increased plasma lithocholic acid may be intimately related to CoQ depletion in blood and tissues. CONCLUSION: Significant CoQ and vitamin E depletion occur in both animals and humans with intrahepatic cholestasis likely as the result of increased hydrophobic bile acids known to produce significant oxidative stress. Present findings further suggest that antioxidant supplementation complementary to traditional treatment may improve cholestasis outcome.

UHPLC-HRMS-Based Analysis of S-Hydroxymethyl-Glutathione, GSH, and GSSG in Human Cells.

Glutathione (GSH) is one of the main antioxidant molecules present in cells. It harbors a thiol group responsible for sustaining cellular redox homeostasis. This moiety can react with cellular electrophiles such as formaldehyde yielding the compound S-hydroxymethyl-GSH (HSMGSH). HSMGSH is the substrate of the enzyme alcohol dehydrogenase 5 (ADH5) and thus a key intermediate in formaldehyde metabolism. In this work, we describe a method for the chemical synthesis of HSMGSH and a pipeline to identify this compound in complex cell extracts by means of ultra-high-performance liquid chromatography coupled to high-resolution spectrometry (UHPLC-HRMS). This method also allows determining GSH and oxidized disulfide (GSSG) in the same samples, thus providing broad information about formaldehyde-GSH metabolism.

Endogenous formaldehyde scavenges cellular glutathione resulting in redox disruption and cytotoxicity.

Formaldehyde (FA) is a ubiquitous endogenous and environmental metabolite that is thought to exert cytotoxicity through DNA and DNA-protein crosslinking, likely contributing to the onset of the human DNA repair condition Fanconi Anaemia. Mutations in the genes coding for FA detoxifying enzymes underlie a human inherited bone marrow failure syndrome (IBMFS), even in the presence of functional DNA repair, raising the question of whether FA causes relevant cellular damage beyond genotoxicity. Here, we report that FA triggers cellular redox imbalance in human cells and in Caenorhabditis elegans. Mechanistically, FA reacts with the redox-active thiol group of glutathione (GSH), altering the GSH:GSSG ratio and causing oxidative stress. FA cytotoxicity is prevented by the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR), which metabolizes FA-GSH products, lastly yielding reduced GSH. Furthermore, we show that GSH synthesis protects human cells from FA, indicating an active role of GSH in preventing FA toxicity. These findings might be relevant for patients carrying mutations in FA-detoxification systems and could suggest therapeutic benefits from thiol-rich antioxidants like N-acetyl-L-cysteine.

Temporal evolution of cardiac mitochondrial dysfunction in a type 1 diabetes model. Mitochondrial complex I impairment, and H2O2 and NO productions as early subcellular events.

The aim of this work was to study the early events that occur in heart mitochondria and to analyse the temporal evolution of cardiac mitochondrial dysfunction in a type 1 diabetes model. Male Wistar rats were injected with Streptozotocin (STZ, single dose, 60 mg × kg-1, i.p.) and hyperglycemic state was confirmed 72 h later. The animals were sacrificed 10 or 14 days after STZ-injection. Heart mitochondrial state 3 O2 consumption sustained by malate-glutamate (21%) or by succinate (16%), and complexes I-III (27%), II-III (24%) and IV (22%) activities were lower in STZ group, when animals were sacrificed at day 14, i.e. ~11 days of hyperglycemia. In contrast, after 10 days of STZ-injection (~7 days of hyperglycemia), only the state 3 O2 consumption sustained by malate-glutamate (23%) and its corresponding respiratory control (30%) were lower in diabetic rats, in accordance with complex I-III activity reduction (17%). Therefore, this time (~7 days of hyperglycemia) has been considered as an "early stage" of cardiac mitochondrial dysfunction. At this point, mitochondrial production rates of H2O2 (117%), NO (30%) and ONOO- (~225%), and mtNOS expression (29%) were higher; and mitochondrial SOD activity (15%) and [GSH + GSSG] (28%) were lower in diabetic rats. Linear correlations between the modified mitochondrial parameters and glycemias were observed. PGC-1α expression was similar between groups, suggesting that mitochondrial biogenesis was not triggered in this initial phase of mitochondrial dysfunction. Consequently, complex I, H2O2 and NO could be considered early subcellular signals of cardiac mitochondrial dysfunction, with NO and H2O2 being located upstream de novo synthesis of mitochondria.

Coenzyme Q10 deficiency in patients with hereditary hemochromatosis.

AIM: Hereditary hemochromatosis (HH) is a group of inherited disorders that causes a slow and progressive iron deposition in diverse organs, particularly in the liver. Iron overload induces oxidative stress and tissue damage. Coenzyme Q10 (CoQ10) is a cofactor in the electron-transport chain of the mitochondria, but it is also a potent endogenous antioxidant. CoQ10 interest has recently grown since various studies show that CoQ10 supplementation may provide protective and safe benefits in mitochondrial diseases and oxidative stress disorders. In the present study we sought to determine CoQ10 plasma level in patients recently diagnosed with HH and to correlate it with biochemical, genetic, and histological features of the disease. METHODS: Plasma levels of CoQ10, iron, ferritin, transferrin and vitamins (A, C and E), liver tests (transaminases, alkaline phosphatase and bilirubin), and histology, as well as three HFE gene mutations (H63D, S654C and C282Y), were assessed in thirty-eight patients (32 males, 6 females) newly diagnosed with HH without treatment and in twenty-five age-matched normolipidemic healthy subjects with no HFE gene mutations (22 males, 3 females) and without clinical or biochemical signs of iron overload or liver diseases. RESULTS: Patients with HH showed a significant decrease in CoQ10 levels respect to control subjects (0.31 ±â€¯0.03 µM vs 0.70 ±â€¯0.06 µM, p < 0.001, respectively) independently of the genetic mutation, cirrhosis, transferrin saturation, ferritin level or markers of hepatic dysfunction. Although a decreasing trend in CoQ10 levels was observed in patients with elevated iron levels, no correlation was found between both parameters in patients with HH. Vitamins C and A levels showed no changes in HH patients. Vitamin E was significantly decreased in HH patients (21.1 ±â€¯1.3 µM vs 29.9 ±â€¯2.5 µM, p < 0.001, respectively), but no correlation was observed with CoQ10 levels. CONCLUSION: The decrease in CoQ10 levels found in HH patients suggests that CoQ10 supplementation could be a safe intervention strategy complementary to the traditional therapy to ameliorate oxidative stress and further tissue damage induced by iron overload.

Coenzyme Q 10 supplementation: A potential therapeutic option for the treatment of intrahepatic cholestasis of pregnancy.

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy specific liver disease characterized by pruritus, elevated serum bile acids and abnormal liver function that may be associated with severe adverse pregnancy outcomes. We previously reported that plasma coenzyme Q10 (CoQ10) is decreased in women with ICP as it is its analogue coenzyme Q9 (CoQ9) in rats with ethinyl estradiol (EE)-induced cholestasis. The aim of the present study was to evaluate the possible therapeutic role of CoQ10 in experimental hepatocellular cholestasis and to compare it with ursodeoxycholic acid (UDCA) supplementation. Bile acids, CoQ9, CoQ10, transaminases, alkaline phosphatase, retinol, α-tocopherol, ascorbic acid, thiobarbituric acid reactive substances, carbonyls, glutathione, superoxide dismutase and catalase were assessed in plasma, liver and/or hepatic mitochondria in control and cholestatic rats supplemented with CoQ10 (250 mg/kg) administered alone or combined with UDCA (25 mg/kg). CoQ10 supplementation prevented bile flow decline (P < 0.05) and the increase in serum alkaline phosphatase and bile acids, particularly lithocholic acid (P < 0.05) in cholestatic rats. Furthermore, it also improved oxidative stress parameters in the liver, increased both CoQ10 and CoQ9 plasma levels and partially prevented the fall in α-tocopherol (P < 0.05). UDCA also prevented cholestasis, but it was less efficient than CoQ10 to improve the liver redox environment. Combined administration of CoQ10 and UDCA resulted in additive effects. In conclusion, present findings show that CoQ10 supplementation attenuated EE-induced cholestasis by promoting a favorable redox environment in the liver, and further suggest that it may represent an alternative therapeutic option for ICP.

Fetal coenzyme Q10 deficiency in intrahepatic cholestasis of pregnancy.

AIM: Intrahepatic cholestasis of pregnancy (ICP) is considered a high-risk condition because it may have serious consequences for the fetus health. ICP is characterized by the accumulation of bile acids in maternal serum which contribute to an imbalance between the production of reactive oxygen species and the antioxidant defenses increasing the oxidative stress experienced by the fetus. Previously, it was reported a significant decrease in plasma coenzyme Q10 (CoQ10) in women with ICP. CoQ10 is a redox substance integrated in the mitochondrial respiratory chain and is recognized as a potent antioxidant playing an intrinsic role against oxidative damage. The objective of the present study was to investigate the levels of CoQ10 in umbilical cord blood during normal pregnancy and in those complicated with ICP, all of them compared to the maternal ones. METHODS: CoQ10 levels and bile acid levels in maternal and umbilical cord blood levels during normal pregnancies (n=23) and in those complicated with ICP (n=13), were investigated. RESULTS: A significant decrease in neonate CoQ10 levels corrected by cholesterol (0.105±0.010 vs. 0.069±0.011, P<0.05, normal pregnancy vs. ICP, respectively), together with an increase of total serum bile acids (2.10±0.02 vs. 7.60±2.30, P<0.05, normal pregnancy vs. ICP, respectively) was observed. CONCLUSIONS: A fetus from an ICP mother is exposed to a greater risk derived from oxidative damage. The recognition of CoQ10 deficiency is important since it could be the starting point for a new and safe intervention strategy which can establish CoQ10 as a promising candidate to prevent the risk of oxidative stress.

Synthesis and Antichlamydial Activity of Molecules Based on Dysregulators of Cylindrical Proteases.

Chlamydia trachomatis is the most common sexually transmitted bacterial disease globally and the leading cause of infertility and preventable infectious blindness (trachoma) in the world. Unfortunately, there is no FDA-approved treatment specific for chlamydial infections. We recently reported two sulfonylpyridines that halt the growth of the pathogen. Herein, we present a SAR of the sulfonylpyridine molecule by introducing substituents on the aromatic regions. Biological evaluation studies showed that several analogues can impair the growth of C. trachomatis without affecting host cell viability. The compounds did not kill other bacteria, indicating selectivity for Chlamydia. The compounds presented mild toxicity toward mammalian cell lines. The compounds were found to be nonmutagenic in a Drosophila melanogaster assay and exhibited a promising stability in both plasma and gastric fluid. The presented results indicate this scaffold is a promising starting point for the development of selective antichlamydial drugs.

Supramolecular solvent-based high-throughput sample treatment platform for the biomonitoring of PAH metabolites in urine by liquid chromatography-tandem mass spectrometry.

Monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs), present in human urine at trace concentrations (viz. from ng L-1 to µg L-1), are considered the main biomarkers of human exposure to PAHs. In this work, we report a simple and high-throughput sample treatment platform to facilitate the biomonitoring of OH-PAHs by making it easier, greener and most cost-effective. This platform is based on the integration of analyte extraction and sample cleanup in a single step by the use of supramolecular solvents with restricted access properties (SUPRAS-RAM). The SUPRAS was spontaneously formed in situ in the urine by the addition of a colloidal suspension of decanoic acid in THF. Metabolites from naphthalene, fluorene, phenanthrene and pyrene were quantitatively extracted (absolute recoveries in the range 91-109%). Polysaccharides and proteins in the urine were excluded from extraction by physical and chemical mechanisms, which allowed the direct analysis of the SUPRAS extract by liquid chromatography tandem mass spectrometry. Absolute matrix effects for OH-PAHs were in the range 92-103%. Method quantification limits for OH-PAHs, without the need for evaporation of the SUPRAS extracts, were in the interval 1.0-6.7 ng L-1. The precision, evaluated in terms of repeatability and reproducibility, varied between 1.1 and 13.8%. The method was successfully applied to the analysis of urine from 16 smoking and non-smoking volunteers. Both analytical and operational features of this method make it suitable to evaluate human exposure to PAHs.

High-dose coenzyme Q10-loaded oleogels for oral therapeutic supplementation.

Coenzyme Q10 (CoQ10) is a mitochondrial respiratory cofactor and potent endogenous antioxidant. In CoQ10-deficient patients, early treatment with high-oral doses (5-50 mg/kg/day) can limit the progression of renal disease and the onset of neurological manifestations. Crystalline CoQ10 is lipophilic, water-insoluble, and poorly absorbed in the gut. Here, CoQ10 showed low bulk density, another important disadvantage in solid oral formulations. Thus, we propose the use of oleogels to maintain dissolved a high-dose of CoQ10 in medium-chain triglyceride (MCT) oil, using ethylcellulose (EC) for gelling, and a surfactant (sorbitan monostearate -SMS- or lecithin). "True gels" were only obtained with the surfactant presence. Thermoreversible oleogels with 1 g of dissolved CoQ10 per 5 g-disk were successfully developed with proved stability and solubility for 12 months (25.0 °C). SMS was better than lecithin as a surfactant because it allowed lower syneresis, higher CoQ10 retention for 12 months, and notably higher oxidative-stability of the MCT-oil, best immobilized by its true gel network. Plastic deformation without fracture was determined under compression, emulating the soft deformation behavior inside the mouth. SMS-oleogels allowed loading a maximal solubilized CoQ10 dose with maximal stability, and may be easier to swallow by CoQ10-deficient patients who suffer from secondary dysphagia.

Relative bioavailability of coenzyme Q10 formulation for paediatric individualized therapy.

OBJECTIVES: Conduct a preliminary comparison of the bioavailability between two formulations: commercial grade coenzyme Q10 (CoQ10) powder (solid formulation) and a new oil-in-water liquid emulsion and their effect on other antioxidants. METHODS: Six healthy individuals participated in a randomized, crossover, open, consecutive design, with a 2-week washout period. Pharmacokinetic parameters were assessed after a single and multiple intakes of 250 mg CoQ10 given daily for 1 week. KEY FINDINGS: The differences in the pharmacokinetic parameters of maximum plasma concentration, area under the curve between 0-360 and 0-4 h, elimination half-life were statistically significant with a relative bioavailability of 489% increase over solid CoQ10 formulation. A multiple dose supplementation increased plasma CoQ10 levels in both formulations, liquid emulsion performing better (2.4- vs 3.9-fold for solid and liquid formulation, respectively) without modifications on other antioxidants. Furthermore, the plasma CoQ10 at 7th day was statistically different between formulations (P < 0.05). CONCLUSIONS: The results obtained showed that liquid emulsion improves the bioavailability of CoQ10 respect to solid form which not only facilitates the individualized administration for the child but in turn could increase the therapeutic efficacy, which should be confirmed by further studies.

Coenzyme Q10 analytical determination in biological matrices and pharmaceuticals.

In recent years, the analytical determination of coenzyme Q10 (CoQ10) has gained importance in clinical diagnosis and in pharmaceutical quality control. CoQ10 is an important cofactor in the mitochondrial respiratory chain and a potent endogenous antioxidant. CoQ10 deficiency is often associated with numerous diseases and patients with these conditions may benefit from administration of supplements of CoQ10. In this regard, it has been observed that the best benefits are obtained when CoQ10 deficiency is diagnosed and treated early. Therefore, it is of great value to develop analytical methods for the detection and quantification of CoQ10 in this type of disease. The methods above mentioned should be simple enough to be used in routine clinical laboratories as well as in quality control of pharmaceutical formulations containing CoQ10. Here, we discuss the advantages and disadvantages of different methods of CoQ10 analysis.

Aerobic degradation of ibuprofen in batch and continuous reactors by an indigenous bacterial community.

Water from six points from the Riachuelo-Matanza basin was analyzed in order to assess ibuprofen biodegradability. In four of them biodegradation of ibuprofen was proved and degrading bacterial communities were isolated. Biodegradation in each point could not be correlated with sewage pollution. The indigenous bacterial community isolated from the point localized in the La Noria Bridge showed the highest degradative capacity and was selected to perform batch and continuous degradation assays. The partial 16S rRNA gene sequence showed that the community consisted of Comamonas aquatica and Bacillus sp. In batch assays the community was capable of degrading 100 mg L(-1) of ibuprofen in 33 h, with a specific growth rate (µ) of 0.21 h(-1). The removal of the compound, as determined by High performance liquid chromatography (HPLC), exceeded 99% of the initial concentration, with a 92.3% removal of Chemical Oxygen Demand (COD). In a down-flow fixed-bed continuous reactor, the community shows a removal efficiency of 95.9% of ibuprofen and 92.3% of COD for an average inlet concentration of 110.4 mg. The reactor was kept in operation for 70 days. The maximal removal rate for the compound was 17.4 g m(-3) d(-1). Scanning electron microscopy was employed to observe biofilm development in the reactor. The ability of the isolated indigenous community can be exploited to improve the treatment of wastewaters containing ibuprofen.

New analytical strategies applied to the determination of Coenzyme Q10 in biological matrix.

In the last few years the importance of Coenzyme Q10 (CoQ10) determination has gained clinical relevance. CoQ10 is a redox-active, lipophilic substance integrated in the mitochondrial respiratory chain which acts as an electron carrier for the production of cellular energy. In addition, it is recognized as a primary regenerating antioxidant playing an intrinsic role against oxidative damage. There are some reports of low CoQ10 levels in a number of disorders, such as cancer, muscular, neurodegenerative, cardiological, and reproductive diseases. Therefore, it is a priority to develop analytical methodologies for evaluating CoQ10 in matrices of greater importance for the correct diagnosis of diseases, simple enough to be used in routine clinical laboratories. In this chapter two recently developed techniques, capillary electrophoresis and microHPLC, for the analysis of CoQ10 in biological matrices, are studied.