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Exercise limitation in COVID-19 survivors is poorly explained. In this retrospective study, cardiopulmonary exercise testing (CPET) was coupled with an oxidative stress assessment in COVID-19 critically ill survivors (ICU group). Thirty-one patients were included in this group. At rest, their oxygen uptake (VO2) was elevated (8 [5.6–9.7] mL/min/kg). The maximum effort was reached at low values of workload and VO2 (66 [40.9–79.2]% and 74.5 [62.6–102.8]% of the respective predicted values). The ventilatory equivalent for carbon dioxide remained within normal ranges. Their metabolic efficiency was low: 15.2 [12.9–17.8]%. The 50% decrease in VO2 after maximum effort was delayed, at 130 [120–170] s, with a still-high respiratory exchange ratio (1.13 [1–1.2]). The blood myeloperoxidase was elevated (92 [75.5–106.5] ng/mL), and the OSS was altered. The CPET profile of the ICU group was compared with long COVID patients after mid-disease (MLC group) and obese patients (OB group). The MLC patients (n = 23) reached peak workload and predicted VO2 values, but their resting VO2, metabolic efficiency, and recovery profiles were similar to the ICU group to a lesser extent. In the OB group (n = 15), no hypermetabolism at rest was observed. In conclusion, the exercise limitation after a critical COVID-19 bout resulted from an altered metabolic profile in the context of persistent inflammation and oxidative stress. Altered exercise and metabolic profiles were also observed in the MLC group. The contribution of obesity on the physiopathology of exercise limitation after a critical bout of COVID-19 did not seem relevant.

The aim of this study was to describe the effects of a 64.2 km ultra-trail on the biomarkers of muscle damage, inflammation and oxidative stress, and compare the results observed with an ECG and an echocardiogram, both performed before and after the race.Thirty-three ultra-trail volunteers (45.8 ± 8.7 years old) were enrolled in our study. Three blood tests were drawn from each runner, one just before (TPRE), one just after (TPOST) and the last 3 h after the end of the race (TPOST3h).All the markers increased. The maximum concentrations observed were at TPOST3h and were significant (p < 0.001) for creatine kinase, creatine kinase isoform MB, high-sensitivity C-reactive protein, uric acid and for the ratio of reduced glutathione to oxidised glutathione. However, in the case of myoglobin, high-sensitive troponin T, N-terminal pro-brain natriuretic peptide, oxidised glutathione, myeloperoxidase, cystatin C and creatinine, the most significant increases were at TPOST (p < 0.001). Modifications were observed in the medical imaging using echocardiography such as reduction of left ventricule end-sytolic and diastolic volumes and left ventricular global longitudinal strain. ECG showed electrical criteria for left ventricular hypertrophy and incomplete right bundle branch block after the race.Endurance races cause significant physiological stress to the body that can be measured by the increase of different biomarkers. From a laboratory perspective, it is important to take into account the possible exercise performed previous to the testing to avoid a misinterpretation of the results. From a training perspective, due to these increases in biomarkers, it is recommended that runners wait at least 72 h after an ultra-trail before subsequent training. In addition a transient impairment of ventricular function due to dehydration were observed.

International audience; BACKGROUND: The present study aimed to examine the effects of spirulina supplementation on pro/antioxidant status, inflammation and skeletal muscle damage markers immediately and 24 h after exhaustive exercise in elite rugby players. METHODS: Seventeen elite male Rugby Union players were randomly assigned to a spirulina (SPI: n = 9) or placebo (PLA: n = 8) group in a double-blind design. Subjects were supplemented with Spirulina platensis (5.7 g day(-1) ) or placebo (isoproteic and caloric) for 7 weeks. At baseline and after 7 weeks of supplementation, blood samples were obtained before (T0), immediately after (T1) and 24 h after (T2) exhaustive exercise. The Yoyo Intermittent Recovery Test Level 2 was used as an exhaustive exercise to induce oxidative stress (OS), inflammation and skeletal muscle damage. The studied parameters included pro/antioxidant status markers (superoxide dismutase, glutathione peroxidase, reduced glutathione/glutathione disulphide ratio, oxidised low-density lipoprotein and F2α-isoprostanes [F2-Isop]), inflammation markers (myeloperoxidase and C-reactive protein [CRP]) and skeletal muscle damage markers (lactate dehydrogenase and creatine kinase [CK]). RESULTS: Our results showed that F2-Isop, CRP and CK levels significantly increased at T1 only in the PLA group (p

Les galopeurs sont capables de courir à plus de 60 km/h sur des distances allant de 900 à 4 000 m pour les courses de plat et de 2 800 à 7 300 m pour les courses d’obstacles. Afin de réaliser de tels efforts, l’approvisionnement en énergie recourt à différentes voies métaboliques dont la contribution dépend de l’intensité et de la durée de l’effort. Une étude de terrain, incluant 11 galopeurs Pur-sang, a été réalisée afin d’évaluer l’implication du métabolisme lipidique lors d’une séance d’entraînement et de déterminer quels marqueurs seraient potentiellement utiles au suivi de l’entraînement. Les analyses biochimiques classiques confirment l’implication du métabolisme lipidique dans l’apport énergétique lors de l’exercice chez le galopeur. Cependant, les informations relatives à leur métabolisation restent limitées. Le recours à de nouveaux marqueurs, tel que le profil en acylcarnitines, apparaît comme un outil intéressant pour investiguer le métabolisme énergétique. Outre l’acquisition de nouvelles connaissances relatives à l’implication des différentes voies métaboliques au cours de l’effort, la détermination du profil des acylcarnitines pourrait s’avérer utile au suivi médicosportif du galopeur.

Summary: Adenosine monophosphate–activated protein kinase (AMPK) acetyl-CoA carboxylase (ACC) signaling is activated in platelets by atherogenic lipids, particularly by oxidized low-density lipoproteins, through a CD36-dependent pathway. More interestingly, increased platelet AMPK–induced ACC phosphorylation is associated with the severity of coronary artery calcification as well as acute coronary events in coronary artery disease patients. Therefore, AMPK–induced ACC phosphorylation is a potential marker for risk stratification in suspected coronary artery disease patients. The inhibition of ACC resulting from its phosphorylation impacts platelet lipid content by down-regulating triglycerides, which in turn may affect platelet function. Key Words: AMPK, acetyl-CoA carboxylase, coronary artery disease, lipidomics, platelet

Background: A key role of oxidative stress has been highlighted in the pathogenesis of COVID-19. However, little has been said about oxidative stress status (OSS) of COVID-19 patients hospitalized in intensive care unit (ICU). Material and Methods: Biomarkers of the systemic OSS included antioxidants (9 assays), trace elements (3 assays), inflammation markers (4 assays) and oxidative damage to lipids (3 assays). Results: Blood samples were drawn after 9 (7–11) and 41 (39–43) days of ICU stay, respectively in 3 and 6 patients. Vitamin C, thiol proteins, reduced glutathione, γ-tocopherol, β-carotene and PAOT® score were significantly decreased compared to laboratory reference values. Selenium concentration was at the limit of the lower reference value. By contrast, the copper/zinc ratio (as a source of oxidative stress) was higher than reference values in 55% of patients while copper was significantly correlated with lipid peroxides (r = 0.95, p &lt, 0.001). Inflammatory biomarkers (C-reactive protein and myeloperoxidase) were significantly increased when compared to normals. Conclusions: The systemic OSS was strongly altered in critically ill COVID-19 patients as evidenced by increased lipid peroxidation but also by deficits in some antioxidants (vitamin C, glutathione, thiol proteins) and trace elements (selenium).

Background: The role of herbal products in the prevention of cardiovascular disease requires supporting evidence. This open pilot study assessed the effect of 2-month supplementation of a combination of olive leaf and fruit extracts (Tensiofytol®, Tilman SA, Baillonville, Belgium) in the clinical management of hypertension and metabolic syndrome (MetS). Methods: A total of 663 (pre)-hypertensive patients were enrolled by general practitioners and supplemented for two months with Tensiofytol®, two capsules per day (100 mg/d of oleuropein and 20 mg/d of hydroxytyrosol). Systolic and diastolic blood pressures (SBP/DBP) were measured before and after treatment. Markers of MetS, high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), fasting blood glucose (FG) and waist circumference (WC), were also examined. Results: Significant reductions (p &lt, 0.0001) in SBP/DBP (13 ± 10/7.1 ± 6.6 mmHg) were observed and similarly in pre-diabetic and diabetic patients. Improvements in SBP/DPB were independent of age and gender but greater for elevated baseline SBP/DBP. Tensiofytol® supplementation also significantly improved markers of MetS, with a decrease of TG (11%), WC (1.4%) and FG (4.8%) and an increase of HDL-C (5.3%). Minor side effects were reported in 3.2% patients. Conclusions: This real-life, observational, non-controlled, non-randomized pilot study shows that supplementation of a combination of olive leaf and fruit extracts may be used efficiently and safely in reducing hypertension and MetS markers.

When conducting research on polyphenols and their effects on health, it is of primary importance to use standardised and validated dietary assessment tools. This paper aims at assessing the validity of a food frequency questionnaire (FFQ) for quantifying dietary polyphenol exposure among healthy adults using the method of triads. Fifty-three healthy adults, aged 20-60, were included in the study. Total dietary polyphenol intake (TDP) estimated by the FFQ was compared with TDP measured by a 3-day food record (FR) and with urinary excretion levels of total polyphenols (TUP). Pearson correlations were calculated between methods. Validity coefficients (VC) were estimated between the three measurements and the 'unknown' true intake. There was a strong correlation between both dietary methods (r = 0.70, p 0.0001). A moderate but significant association was observed between FFQ-derived TDP and TUP (r = 0.32, p = 0.020). The method of triads yielded a VC for the FFQ of 0.63 (95%CI: 0.41-0.84), indicating a strong relationship between FFQ-derived TDP and the true polyphenol intake. This study shows that the FFQ is an adequate tool not only for measuring dietary polyphenol exposure in nutrition epidemiological studies but also for guiding clinicians in dietary advice and counselling.

The objective of this study is to investigate the effects of three home cooking methods traditionally used all around the world (boiling, steaming and microwaving) in two vegetables: broccoli and red cabbage. Their effects on phytochemical content (i.e., polyphenols, ascorbic acid, anthocyanins, glucosinolates, and sulforaphane) and on total antioxidant capacity were investigated. Steaming and microwaving were explored to understand the effect of cooking time and/or cooking power. Nutrient and health-promoting compounds in broccoli and red cabbage are significantly affected by domestic cooking. The boiling seems to result in a very significant loss of nutritional compounds by leaching in cooking water. However, steaming and microwaving allowed the preservation of the higher quantities of bioactive compounds such as antioxidant compounds and glucosinolates. Microwave cooking significantly influenced the concentrations of bioactive compounds such as ascorbic acid, anthocyanins and sulforaphane. Sulforaphane content increased four or six times during the first minute of microwaving in the two vegetables.

Background Abdominal aortic aneurysm (AAA) is a degenerative disease that causes mortality in people aged > 65 years. Increased reactive oxygen species (ROS) and oxidative stress seem to play a pivotal role in AAA pathogenesis. Several sources of ROS have been identified in aortic tissues using experimental models: inflammation, increased activity of NAD(P)H or NOX, over-expression of inducible nitric oxide synthase (iNOS), uncoupled endothelial nitric oxide synthase (eNOS), platelets activation and iron release from hemoglobin. Objectives Human studies confirmed that oxidative stress and endothelial dysfunction, an important source of ROS production, were well associated with AAA development. Reducing oxidative stress by antioxidants can therefore be a good strategy for limiting AAA development. The objective of the present study is to review literature data favoring or not such a hypothesis. There is currently no evidence showing that strategies using classical low molecular weight antioxidants (vitamins C and E, β- carotene) as target for ROS is effective to reduce human AAA progression. However, recent epidemiological data have highlighted the positive role of a diet enriched in fruits which contain high amounts of antioxidant polyphenols. By their ability to restore endothelial function and also their capacity to stimulate enzymatic antioxidants through activation of the Keap1/Nrf2/ARE pathway, polyphenols can represent a promising treatment target for reducing human AAA progression. Conclusion Clinical studies are therefore urgently necessary to confirm the potential beneficial effect of polyphenols in preventing or limiting AAA.

Objective Polyphenol-rich products such as fruit juices have been found to have strong antioxidant capacities and to induce potent endothelium-dependent relaxation. We evaluated whether the commercial blackcurrant juices induced endothelium-dependent relaxation of isolated coronary arteries can be related to their antioxidant capacity and/or phenolic content. Methods Six different commercial blackcurrant juices were selected. Their main phenolic compounds were measured by ultra-performance liquid chromatography and antioxidant capacity was evaluated by spectrometric methods. Vascular reactivity studies with these juices were done using isolated porcine coronary arteries. Results The six different commercial blackcurrant juices induced relaxation ranging from 21% to 100% at the concentration of 0.5% volume per volume (v/v). The relaxation induced at 0.5% v/v was not correlated to their antioxidant capacity measured by either oxygen radical antioxidant capacity or DPPH (2,2-diphenyl-1-picrylhydrazyl) assays and also not to the ascorbic acid, total polyphenols, total flavanols, and total phenolic acid contents. In contrast, the amplitude of the relaxation was correlated to the total anthocyanins content and the individual anthocyanin concentration. Conclusions Correlations between relaxation amplitude and total anthocyanin or individual anthocyanin contents are of interest for the development of functional blackcurrant beverages with the potential to promote vascular protection.

Visual Abstract, Highlights • Platelet phosphoACC is a marker for risk stratification in suspected CAD patients. It identifies high-risk CAD patients and correlates with severity of coronary artery calcification. • The triglycerides/high-density lipoprotein cholesterol ratio is strongly associated with increased phosphoACC in circulating platelets. PhosphoACC is a metabolic signature of the platelet-proatherogenic lipid interplay in CAD patients. • Phosphorylation and inhibition of acetyl-CoA carboxylase impacts platelet lipid content by down-regulating triglycerides lipid species., Summary Adenosine monophosphate–activated protein kinase (AMPK) acetyl-CoA carboxylase (ACC) signaling is activated in platelets by atherogenic lipids, particularly by oxidized low-density lipoproteins, through a CD36-dependent pathway. More interestingly, increased platelet AMPK–induced ACC phosphorylation is associated with the severity of coronary artery calcification as well as acute coronary events in coronary artery disease patients. Therefore, AMPK–induced ACC phosphorylation is a potential marker for risk stratification in suspected coronary artery disease patients. The inhibition of ACC resulting from its phosphorylation impacts platelet lipid content by down-regulating triglycerides, which in turn may affect platelet function.

BACKGROUND: Several studies have shown that cherries, especially sour cultivars, contain substantial amounts of phenolic compounds. OBJECTIVE: This study aims to (i) analyze the total phenolic compound (TPC) content and the antioxidant capacity (AC) of a large range of cultivars using the same methodology in one laboratory, and (ii) determine the possible relationship between agronomic characteristics and AC. METHODS: A total of 245 samples including sweet, sour and hybrid cultivars from our collections were harvested at their optimum maturity and characterized according to their TPC, DPPH and ORAC values. RESULTS: The TPC content and DPPH and ORAC values varied greatly among the cherries, with the sour cultivars presenting higher levels than the sweet ones. The PCA plot showed a slight grouping by species and confirmed the high TPC content level in sour cultivars. The bi-colored cultivars had lower TPC and antioxidant capacity (AC) values than dark-colored ones, indicating that coloration could give an indication of the AC of fruits. No significant relationship between the agronomic and chemical properties was highlighted. CONCLUSIONS: Cherry fruits, especially from sour cultivars, represent an important source of bioactive compounds and could attract new interest as a ‘functional food’.

Chronic liver diseases with portal hypertension are characterized by a progressive vasodilatation, endothelial dysfunction, and NADPH oxidase-derived vascular oxidative stress, which have been suggested to involve the angiotensin system. This study evaluated the possibility that oral intake of polyphenol-rich blackcurrant juice (PRBJ), a rich natural source of antioxidants, prevents endothelial dysfunction in a rat model of cirrhosis induced by chronic bile duct ligation (CBDL), and, if so, determined the underlying mechanism. Male Wistar rats received either control drinking water or water containing 60 mg/kg gallic acid equivalents of PRBJ for 3 weeks before undergoing surgery with CBDL or sham surgery. After 4 weeks, vascular reactivity was assessed in mesenteric artery rings using organ chambers. Both the acetylcholine-induced nitric oxide (NO)- and endothelium-dependent hyperpolarization (EDH)-mediated relaxations in mesenteric artery rings were significantly reduced in CBDL rats compared to sham rats. An increased level of oxidative stress and expression of NADPH oxidase subunits, COX-2, NOS, and of the vascular angiotensin system are observed in arterial sections in the CBDL group. Chronic intake of PRBJ prevented the CBDL-induced impaired EDH-mediated relaxation, oxidative stress, and expression of the different target proteins in the arterial wall. In addition, PRBJ prevented the CBDL-induced increase in the plasma level of proinflammatory cytokines (interleukin [IL]-1α, monocyte chemotactic protein 1, and tumor necrosis factor α) and the decrease of the anti-inflammatory cytokine, IL-4. Altogether, these observations indicate that regular ingestion of PRBJ prevents the CBDL-induced endothelial dysfunction in the mesenteric artery most likely by normalizing the level of vascular oxidative stress and the angiotensin system.

Systemic sclerosis (SSc) is a chronic multisystemic connective tissue disease characterized by progressive fibrosis affecting skin and internal organs. Despite serious efforts to unveil the pathogenic mechanisms of SSc, they are still unclear. High levels of reactive oxygen species (ROS) in affected patients have been shown, and ROS are suggested to play a role in fibrosis pathogenesis. In this study we evaluate ROS levels in nonfibrotic and fibrotic skin of patients with SSc and we compare them with those obtained from healthy controls. We enrolled nine SSc patients fulfilling the EULAR/ACR classification criteria and seven healthy controls. Patients included four men and five women with mean age of 46 ± 10 years. Controls were matched by sex and age. All patients were affected by the diffuse cutaneous form of SSc and the ANA pattern anti-Scl70. Mean disease duration was 7.5 ± 5 years. Skin involvement was evaluated by modified Rodnan skin score. Skin samples (4-mm punch biopsy) were taken from fibrotic skin and nonfibrotic skin of patients and from healthy controls as well. To detect ROS, specimens were analyzed immediately after sampling by electron paramagnetic resonance spectroscopy. Blood samples were drawn from all patients and controls to assess oxidative stress biomarkers. ROS levels (expressed as median and range, in nmol/L/min/mg of dry weight) were 24.7 (10.9-47.0) in fibrotic skin, 18.7 (7.3-34.0) in nonfibrotic skin, and 7.7 (3.5-13.6) in healthy control skin. ROS levels in fibrotic and nonfibrotic skin of SSc patients were significantly higher than in healthy controls (p = 0.002 and p = 0.009, respectively). ROS levels in fibrotic skin were raised in comparison to nonfibrotic skin, when samples related to each patient were compared (p = 0.01). ROS levels in fibrotic skin were correlated with forced vital capacity (r = -0.75, p = 0.02) and erythrocyte sedimentation rate (r = 0.70, p = 0.04). All other clinical and lab parameters showed no significant correlation. Compared to controls, blood from SSc patients showed lower ascorbate (vitamin C) levels (8 (3.8-9.8) vs 10.5 (9-19.1) mg/L, p = 0.004) and higher lipid peroxides (873.5 (342-1973) vs 422 (105-576) μmol/L, p = 0.004). Our results indicate the presence of high oxidative stress in both nonfibrotic skin and fibrotic skin of SSc patients, but with higher tendency in the latter. Raised ROS levels in nonfibrotic skin of SSc patients might be a hint of early involvement in skin fibrogenesis. However, a longitudinal prospective study is necessary for such proof.

Aims Facioscapulohumeral muscular dystrophy (FSHD) causes progressive muscle weakness and loss. This study aims to compare changes in quadriceps oxygenation and hemodynamics during maximal voluntary quadriceps isometric contraction (MVC Q) and to determine the relationships between these parameters and systemic oxidative stress markers and muscle structural parameters and muscle volume in patients with FSHD and healthy controls. Methods and results 17 patients with FSHD and 14 sedentary healthy controls were matched for age and physical activity level. Blood antioxidant status and stress markers were evaluated. The quadriceps tissue oxygenation index was evaluated by near infrared spectroscopy during MVC Q. Quadriceps volume was determined by magnetic resonance imaging. Quadriceps muscle samples were obtained to evaluate muscle fiber typology and mitochondria morphology by transmission electron microcopy (TEM). Groups were compared by the unpaired Student t-test or by the non-parametric Kruskal-Wallis test in case of skewed distributions with p

Wines produced from various grape varieties present different properties affecting taste and color. The hypothesis was that grape genotype could have a deep impact on wine antioxidant properties and phenolic composition. But in this study on 38 different wines of 4 main grape varieties, large variability in the levels of individual phenolic compounds as well as in antioxidant capacity was observed in each grape variety. Comparisons of the wine varieties based on their individual phenolic profile (flavonols, anthocyanidins, flavan-3-ols, phenolic acids, resveratrol, etc.) and antioxidant capacities (ORAC, DPPH, hemolysis, ESR, and total phenolics) showed limited differences. An exception was the group of wines made from the grape variety Pinot Noir, in which the range of phenolic compounds was different from the other wines: anthocyanidins (87 mg L−1, 119–206 mg L−1 in other grape varieties) and flavonols (17 mg L−1, 20–57 mg L−1in others except Primitivo) showed lower levels while flavanols (327 mg L−1, 152–244 mg L−1 in others) and phenolic acids (161 mg L−1, 103–152 mg L−1 in others) showed levels higher than in the other wines. This different profile was associated with a lower antioxidant capacity (i.e. mean ORAC value: 20988 for Pinot Noir, 27820–33651 for others; ORAC concentration μmol TE L−1; see Section 2.3.3 ).

BACKGROUND: Small dark fruits represent one of the most important sources of bioactive compounds with antioxidant capacity in the human diet. The content of health-promoting antioxidants in these fruits may be important information to take into account when a fruit producer has to choose which cultivar to grow. OBJECTIVE: It is important to know how antioxidant capacity and antioxidant compounds as total phenolics and ascorbic acid vary between 9 small dark fruit species and for each species among cultivars (2 to 10 per species). METHODS: The antioxidant capacity (ORAC assay), total phenolic (Folin-Ciocalteu) and ascorbic acid content were measured in 9 fruits (plums, blackcurrants, blackberries, blueberries, cherries, redcurrants, raspberries, white currants and gooseberries) / 42 cultivars harvested at maturity during their high production period. RESULTS: The comparison of the average of the various cultivars of each small fruits showed that blackcurrants had the best antioxidant capacity (with plums), the highest ascorbic acid content and the highest total phenolic content (with blackberries). The present study shows that total phenolic compounds, ascorbic acid and antioxidant capacity strongly differed between genotypes of each small dark fruits. Other parameters as harvest time, culture conditions and maturity degree at the harvest may also influence the antioxidant capacity of small fruits. CONCLUSIONS: Among small dark fruits, blackcurrants have high qualities. Choices of variety, harvest time and maturity degree are important for all fruits.

The present study was designed to test the hypothesis that an increased consumption of fruits and vegetables up to 600 g per day in type 2 diabetes patients can reduce oxidative damages to lipids. After a clinical examination, 29 type 2 diabetes patients were divided into two groups: the first one did not receive any special instructions about the diet while the second one received fruits and vegetables consumption advices thanks to a picture catalogue describing types of fruits and vegetables as well as quantities to be eaten every day. After two months of intervention, plasma concentrations in vitamin C, b-carotene and polyphenols remained unchanged in both groups when compared to baseline values. No significant decrease in lipid peroxidation as evidenced by nine biomarkers (malonaldehyde as TBAR’s, lipid peroxides, oxidized LDL, antibodies against oxidized LDL, isoprostanes, 7-keto-cholesterol, 7b-hydroxycholesterol, 4-hydroxynonenal metabolite, LDL size) was also noted. In conclusion, our findings confirmed the fact that the effect of high intake of fruits and vegetables on reducing oxidative damage to lipids remains largely controversial even in patients having an oxidative stress profile. Moreover, the present leaves open the question of the most appropriate markers of lipid peroxidation since only small correlations were evidenced between the large battery of tests investigated.

The influence of sample dilution on the measurement of antioxidant capacity was analyzed. To ensure the reproducibility of results, it is necessary to realize such scarce investigations. This study focuses on different antioxidant capacity assays commonly used for the analysis of pure substances and food extracts. For all compounds and foods tested in most of the four assays (Trolox equivalent antioxidant capacity, 2,2-diphenyl-1-picrylhydrazyl, and oxygen radical absorbance capacity), effects of sample dilution on the measured (and recalculated) antioxidant capacity were observed, with differences up to 28 % between dilutions. An extrapolation method was proposed to obtain a “real value” thus to minimize the effects of the sample dilution. This extrapolation method is relatively simple, based on a linear regression of 4 or 5 appropriate dilutions of the sample and applicable to the various assays. The use of such a method will improve the consistency of interlaboratory antioxidant capacity data and thus permit better comparisons. In contrast, there was no dilution problem with ferric reducing antioxidant power assays.

It is widely accepted that ORAC is a useful method for assessing food extracts that contain various antioxidants. The principal aim of this study was to validate the ORAC assay. We first identified parameters that can interfere with the ORAC assay and we optimized it. Then, experiments were conducted to determine the limits of linearity and response function, to determine the accuracy profiles to circumvent some of the drawbacks of traditional validation procedures. Trueness, selectivity and limits of quantification of the method were also determined. Our objective of ORAC method validation is thus to give guarantees that most of the results generated during use of this method will be close enough to unknown true value of antioxidant capacity of food matrices. The validation results indicate that the described method will give accurate and reliable results for Trolox equivalent values ranging from 50 to 200 μmol/L.

Introduction L’atteinte musculaire peripherique et l’intolerance a l’effort des patients BPCO n’est que partiellement amelioree par le reentrainement a l’effort (REE) [1] . Le stress oxydant (SO) de repos et d’exercice chez ces patients, regulent des voies de signalisations impliquees dans l’endurance et la force musculaire, limitant les effets du REE. Contrairement aux sujets sains, le REE n’augmente pas les defenses antioxydantes dans la BPCO, exposant le muscle aux effets deleteres du SO. Les patients BPCO pourraient donc tirer benefice d’une supplementation en antioxydants durant le REE. Base sur l’observation recente de deficits en antioxydants dans la BPCO [2] , nous avons compare les effets d’une supplementation ciblee en antioxydants a dose non pharmacologique (vitamine C, E, zinc et selenium) contre placebo, associe au REE, sur l’atteinte musculaire et la tolerance a l’effort de patients BPCO. Methodes Au total, 64 patients BPCO inclus dans cet essai randomise, controle, en double insu ont effectue en debut et apres 4 semaines de REE au seuil ventilatoire : epreuve d’effort (mesure de VO2 sL), fonction et biopsie musculaire. Resultats Au total, 27 patients ont fini l’etude dans le groupe « placebo » et 31 dans le groupe « antioxydant ». Les 2 groupes etaient similaires en termes de : caracteristiques, observance, REE, nombre d’exacerbations et apports en antioxydants. Les patients du groupe « antioxydant » ont specifiquement ameliore les taux de vitamine E et selenium (p = 0,05 et p Conclusion Pour la premiere fois, nous montrons dans la BPCO que la combinaison REE et supplementation en antioxydants, induit specifiquement des gains de 9 % a 20 % pour des parametres musculaires-cles. Ces resultats ouvrent la perspective d’une etude clinique en vie reelle evaluant les benefices potentiels a long terme d’une telle supplementation.

Introduction: A fatty acid (FA) is a carboxylic acid with a long aliphatic chain, which is either saturated or unsaturated. Recently, the role of FA and particularly omega-3 and -6 has emerged as cardiovascular risk factor in the literature. The aim of our study was to establish reference values for these FA and to compare them with data obtained in a population of acute myocardial infarction (AMI) patients. Materials and methods: Hundred thirty five healthy subjects (59.38 ± 27.12 yo, 75 men) were selected as reference population. We also evaluated FA in thirty three patients (55 ± 9 yo, 23 men) admitted in the Emergency Department of our Institution for AMI. The fasting whole blood was drawn in vacutainer containing EDTA. Before analysis, samples were washed and transmethylated. We performed the quantification of different FA by gas chromatography associated with flame ionization detector (GCFID). Results: We obtained results in control healthy patients to be used as reference values. In the AMI group, levels of omega-6 were significantly higher (p 0.05) for C18:2n6 and C18:3n6 than the reference population and omega-3 values were significantly lower (p 0.01) compared to reference value for C22:6n3. The omega-3 index was lower and the ratio omega-6/omega-3 was higher in AMI group compared to reference values. Conclusions: We have established reference value for FA and have compared these values with the results obtained in AMI population. FA determination is a new tool we are able to use and to process in our laboratory which can help the clinician to screen patients with the highest cardiovascular risks because of the implication of FA in the etiopathogeny of atherosclerosis.

In COPD patients oxidative stress (OS) is a limiting factor of exercise training effects on muscle impairment during pulmonary rehabilitation (PR). Antioxidant supplementation used during PR appeared inappropriate to cope with COPD-related antioxidant deficits. We therefore investigated whether exercise training PR, combined with non-pharmacological antioxidant supplementation (vitamins C and E, zinc, selenium), would have beneficial effects on muscle impairment and exercise capacity. 58 stable COPD patients (61 years; FEV1: 59%predicted) referred for a 4-week PR program, were recruited in a double-blind randomized, placebo-controlled clinical trial. Primary outcome was change in quadriceps endurance (Qend). Secondary outcomes were: quadriceps maximal voluntary contraction (QMVC), exercise capacity (maximal oxygen uptake (Vo 2sl ), systemic OS markers and muscle fiber cross sectional area (CSA). Qend was significantly increased in both COPD patient groups. QMVC and VO 2sl were improved (+9 and +16%, respectively) exclusively in “PR+antioxidant” group (p=0.01 and p In conclusion, this study showed that antioxidant supplementation combining vitamin C, E, zinc and selenium, improves the PR effects on QMVC, Vo 2sl and muscle fiber CSA by enhancing antioxidant capacity of COPD patients.

Introduction: Re-transfusion of lipid particles and activated leucocytes with shed mediastinal blood (SMB) can aggravate cardiopulmonary bypass-associated inflammation and increase the embolic load. This study evaluated the fat and leucocyte removal capacity of the RemoweLL cardiotomy reservoir. Methods: Forty-five patients undergoing elective on-pump cardiac surgery were randomly allocated to filtration of SMB using the RemoweLL or the Admiral cardiotomy reservoir. The primary outcome was a drop in leucocytes and lipid particles obtained with the two filters. The effect of the filters on other blood cells and inflammatory mediators, such as myeloperoxidase (MPO), was also assessed. Results: The RemoweLL cardiotomy filter removed 16.5% of the leucocytes (pConclusion: The RemoweLL filter more effectively removed leucocytes from SMB than the Admiral. It offered no advantage in terms of lipid particle clearance.

Background Abdominal aortic aneurysm (AAA) is a major cause of preventable deaths in older patients. Oxidative stress has been suggested to play a key role in the pathogenesis of AAA. However, only few studies have been conducted to evaluate the blood oxidative stress status of AAA patients. Methods and results Twenty seven AAA patients (mean age of 70 years) divided into two groups according to AAA size (≤50 or >50 mm) were compared with an age-matched group of 18 healthy subjects. Antioxidants (vitamins C and E, β-carotene, glutathione, thiols, and ubiquinone), trace elements (selenium, copper, zinc, and copper/zinc ratio) and markers of oxidative damage to lipids (lipid peroxides, antibodies against oxidized patients, and isoprostanes) were measured in each subject. The comparison of the three groups by ordinal logistic regression showed a significant decrease of the plasma levels of vitamin C (P = 0.011), α-tocopherol (P = 0.016) but not when corrected for cholesterol values, β-carotene (P = 0.0096), ubiquinone (P = 0.014), zinc (P = 0.0035), and of selenium (P = 0.0038), as AAA size increased. By contrast, specific markers of lipid peroxidation such as the Cu/Zn ratio (P = 0.046) and to a lesser extent isoprostanes (P = 0.052) increased. Conclusion The present study emphasizes the potential role of the oxidative stress in AAA disease and suggests that an antioxidant therapy could be of interest to delay AAA progression.

Blackcurrant berries contain high amounts of flavonoids with various health benefits as anti-inflammatory properties attributed to their antioxidant potential. Leaves and buds actually used to produce food supplement could also exhibit such interesting properties. In the literature, various methods are often used and valid indicators of the antioxidant potential of dietary substances. However these assays do not provide evidence that antioxidants have in viv o or ex vivo activity when consumed. To obtain biologically relevant information, the antioxidant activities of the extracts were evaluated on cellular models implicating the measurement of blood haemolysis, the Cellular Antioxidant Activity on endothelial cells and the anti-inflammatory activities on isolated equine stimulated neutrophils and purified myeloperoxidase. These tests generally showed that the blackcurrant leaf extract have the highest antioxidant and anti-inflammatory (inhibition of MPO activity and ROS production on activated neutrophils) capacities correlated to the highest total phenolics content.