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1.
Acta Cardiol ; 76(7): 739-747, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32539581

RESUMO

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.


Assuntos
Ecocardiografia , Troponina T , Adulto , Biomarcadores , Eletrocardiografia , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo
2.
Int J Sports Med ; 37(9): 680-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27286182

RESUMO

The purpose of this study was to follow-up the variation of pro-/antioxidant status throughout a whole season in elite professional soccer players from the French league (n=19, 18.3±0.6 years) and to examine a possible link between these variations and training load. 5 time points (T1, T2, T3, T4, T5) were proposed to surround crucial periods of training during the whole season: the pre-season training/mid-season periods (T1-T2 and T3-T4), the championship or in-season periods (T2-T3 and T4-T5). At these times, blood samples were collected to measure pro-/antioxidant status (in erythrocytes: the ratio of reduced glutathione/oxidized glutathione, superoxide dismutase and glutathione peroxidase activities, in plasma: alpha-tocopherol, beta-carotene), and dietary intakes were also recorded. Training loads were quantified by the rating of perceived exertion method weekly throughout the season. Pro-/antioxidant-related measurements showed no modifications except for GSH/GSSG ratio, which evolved significantly between season periods: from 36.43±4.15 (T1) to 115.99±16.43 (T2) to 91.64±21.24 (T3) to 202.29±29.26 (T4) to 59.61±14.61 (T5). We observed a significant correlation (r(2)=0.84) between changes in GSH/GSSH ratio and cumulated mean training loads. In conclusion, these results suggest that the redox status of professional soccer players is altered according to training period (in-season periods) and that GSH/GSSH ratio variations are correlated with cumulated training loads.


Assuntos
Antioxidantes/fisiologia , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Futebol/fisiologia , Adolescente , Atletas , Glutationa/sangue , Glutationa Peroxidase/sangue , Humanos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/sangue , Adulto Jovem , alfa-Tocoferol/sangue , beta Caroteno/sangue
3.
Rev Med Liege ; 69(5-6): 270-5, 2014.
Artigo em Francês | MEDLINE | ID: mdl-25065231

RESUMO

Antioxidant supplementation in the form of pills is thought to slow down the aging process through the "free radical" scavenger activity of these compounds. The idea arose from the "Free Radical Theory of Ageing" (FRTA), initially developed by Harman in 1956. In the present paper, we present some arguments against this theory. One of the most pertinent is that "free radicals", more properly renamed as reactive oxygen species (ROS), play important biological roles in defense mechanisms of the organism as illustrated, in particular, by the hormesis phenomenon. Surprisingly, a moderate production of ROS has been shown to extend the life span in animals.


Assuntos
Envelhecimento/metabolismo , Antioxidantes/administração & dosagem , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Idoso , Idoso de 80 Anos ou mais , Suplementos Nutricionais , Hormese , Humanos , Longevidade
4.
Redox Rep ; 17(4): 139-44, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22732574

RESUMO

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, ß-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, ß-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.


Assuntos
Antioxidantes/metabolismo , Aneurisma da Aorta Abdominal/sangue , Estresse Oxidativo , Oligoelementos/sangue , Idoso , Aneurisma da Aorta Abdominal/patologia , Ácido Ascórbico/sangue , Biomarcadores , Estudos de Casos e Controles , Cobre/sangue , Feminino , Humanos , Isoprostanos/sangue , Peroxidação de Lipídeos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Zinco/sangue , alfa-Tocoferol/sangue
5.
Curr Med Chem ; 17(30): 3591-604, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20738243

RESUMO

This paper will focus on understanding the role and action of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the molecular and biochemical pathways responsible for the regulation of the survival of hair cells and spiral ganglion neurons in the auditory portion of the inner ear. The pivotal role of ROS/RNS in ototoxicity makes them potentially valuable candidates for effective otoprotective strategies. In this review, we describe the major characteristics of ROS/RNS and the different oxidative processes observed during ototoxic cascades. At each step, we discuss their potential as therapeutic targets because an increasing number of compounds that modulate ROS/RNS processing or targets are being identified.


Assuntos
Cóclea/metabolismo , Doenças Cocleares/metabolismo , Estresse Oxidativo , Aminoglicosídeos/toxicidade , Antioxidantes/farmacologia , Cisplatino/toxicidade , Doenças Cocleares/terapia , Humanos , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Nitrogênio/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/toxicidade
6.
J Anim Physiol Anim Nutr (Berl) ; 93(3): 325-30, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19646107

RESUMO

Selenium is a trace element of importance for animal health. It is essential for adequate functioning of many enzymes such as, the antioxidant enzyme, glutathione peroxidase, which protects the cell against free radicals. A muscular effort induces a rise in reactive oxygen species production which, in turn, can generate an oxidative stress. Two groups of eight racing pigeons were fed respectively with a diet containing 30.3 (control group) and 195.3 (selenium group) microg selenium/kg diet. The pigeons were submitted to a standardised simulation of a flying effort during 2 h. Blood was taken before and after the effort to measure antioxidant markers and blood parameters related to muscle metabolism. Plasma selenium concentration and glutathione peroxidase activity were significantly higher in the selenium group. There were no significant differences for the other measured parameters. As a consequence of the effort, the pigeons of the selenium group showed a higher increase of glutathione peroxidase activity and a smaller increase of plasma lactate concentration. Variations because of the effort in the other markers were not significantly different between the two groups. It is concluded that the selenium status was improved with the feeding of feedstuffs high in Selenium.


Assuntos
Ração Animal/análise , Antioxidantes/metabolismo , Columbidae/fisiologia , Voo Animal/fisiologia , Selênio/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Biomarcadores/sangue , Dieta/veterinária , Metabolismo Energético , Selênio/química , Selênio/metabolismo
7.
Int J Obes (Lond) ; 33(4): 447-55, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19363498

RESUMO

HYPOTHESIS: Basal insulin resistance (IR) and inflammation exacerbate post-exercise oxidative stress (OS) in overweight adolescent girls. DESIGN: Cross-sectional study, effect of incremental ergocycle exercise until exhaustion on OS markers. PARTICIPANTS: Normal-weight (control) (n=17, body mass index (BMI): 20-24.2 kg/m(2)) and overweight adolescent girls (n=29, BMI: 24.1-36.6 kg/m(2)). MEASUREMENTS: Dietary measurement, physical activity assessment (validated questionnaires), fat distribution parameters (by dual-energy X-ray absorptiometry and anthropometry) and maximal oxygen consumption (VO2peak). Blood assays include the following: (1) at fasting state: blood cell count, lipid profile, and IR parameters (leptin/adiponectin ratio (L/A), homeostasis model assessment of IR, insulin/glucose ratio; (2) before exercise: inflammation and OS markers (interleukin-6 (IL-6), C-reactive protein (CRP), myeloperoxidase (MPO), reduced glutathione/oxidized glutathione ratio (GSH/GSSG), 15 F(2)alpha-isoprostanes (F(2)-Isop), lipid hydroperoxides (ROOH), oxidized low-density lipoprotein (ox-LDL)) and antioxidant status (superoxide dismutase (SOD), glutathione peroxidase (GPX), vitamin C, alpha-tocopherol and beta-carotene); and (3) after exercise: inflammation and OS markers. RESULTS: At rest, overweight girls had a deteriorated lipid profile and significantly higher values of IR parameters and inflammation markers, compared with the control girls. These alterations were associated with a moderate rest OS state (lower GSH/GSSG ratio, alpha-tocopherol/total cholesterol (TC) ratio and GPX activity). In absolute values, overweight girls exhibited higher peak power output and oxygen consumption (VO2peak), compared with the control girls. Exercise exacerbated OS only in the overweight group (significant increase in F(2)-Isop, ROOH and MPO). As hypothesized, basal IR and inflammation state were correlated with the post-exercise OS. However, the adjustment of F(2)-Isop, ROOH and MPO variation per exercise VO(2) variation canceled the intergroup differences. CONCLUSION: In overweight adolescent girls, the main factors of OS, after incremental exhaustive exercise, are not the basal IR and inflammation states, but oxygen overconsumption.


Assuntos
Resistência à Insulina , Insulina/análogos & derivados , Sobrepeso/metabolismo , Consumo de Oxigênio , Adolescente , Antropometria , Índice de Massa Corporal , Estudos Transversais , Metabolismo Energético , Teste de Esforço/métodos , Feminino , Humanos , Inflamação/metabolismo , Insulina/metabolismo , Insulina de Ação Prolongada , Líbano/epidemiologia , Obesidade/complicações , Obesidade/metabolismo , Sobrepeso/complicações , Estresse Oxidativo , Adulto Jovem
8.
Rev Med Liege ; 62(10): 628-38, 2007 Oct.
Artigo em Francês | MEDLINE | ID: mdl-18069575

RESUMO

Oxidative stress is defined as an imbalance between the production of reactive oxygen species (ROS) and the antioxidant network, in favour of the former. Our lifestyle (smoking, alcoholism, obesity, intense physical exercise), but also our inadequate diet, contributes to significantly increase the production of ROS in our organism. This is potentially associated with an increased risk of developing ageing-related pathologies such as cardiovascular diseases and cancer. As a matter of prevention, it is necessary to have in hands a high technology allowing to correctly evidence the oxidative stress status of an individual in order to render optimal our antioxidant defences and to decrease the oxidative damages in DNA, proteins and lipids.


Assuntos
Estresse Oxidativo/fisiologia , Aminoácidos/metabolismo , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Biomarcadores/análise , Carotenoides/metabolismo , Coenzimas , Dano ao DNA , Diabetes Mellitus/etiologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Radicais Livres/análise , Glutationa Peroxidase/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Lipoproteínas/metabolismo , Lipídeos de Membrana/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Tiorredoxinas/metabolismo , Oligoelementos/metabolismo , Ubiquinona/análogos & derivados , Vitamina E/metabolismo , Vitaminas/metabolismo
9.
Hum Reprod ; 22(8): 2335-43, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17584753

RESUMO

BACKGROUND: Oxidative stress is associated with the development of several disorders including cardiovascular disease and cancer. Among conditions known to influence oxidative stress, the use of oral contraception (OC) in women has been a matter of ongoing discussion. METHODS: A total of 897 eligible and healthy volunteers were recruited from among the patients of 50 general practitioners participating in the ELAN study (Etude Liégeoise sur les ANtioxydants). A subsample consisting of 209 women aged 40-48 years was studied for a comprehensive oxidative stress status (OSS), including the analysis of antioxidants, trace elements and three markers of oxidative damage to lipids. Among 209 subsample, 49 (23%) were OC users (OCU), 119 (57%) non-contraception users (NCU) and 41 (20%) were intrauterine (hormonal and copper) devices users (IUD). RESULTS: After adjustment for smoking, systolic and diastolic blood pressure and BMI (or waist circumference), a marked and significant increase in lipid peroxides was observed among OCU women when compared with NCU and IUD users. A cut-off value of 660 microM in lipid peroxides allowed the discrimination of OCU from the two other groups. In contrast, no difference was observed in the plasma concentration of both oxidized low-density lipoprotein (LDL) and their related antibodies. The increased level in lipid peroxides was strongly related to higher concentrations of copper (r < 0.84; P < 0.0001, cut-off value 1.2 mg/l). When compared with NCU and IUD users, plasma antioxidant defences were significantly altered in OCU women as shown by lower levels of beta-carotene (decrease of 39%; P < 0.01) and gamma-tocopherol (decrease by 22%; P < 0.01). In contrast, higher concentrations of selenium (increased by 11.8%; P < 0.01) were observed in OCU women. Blood concentrations of vitamin C, alpha-tocopherol and zinc were unaffected by OC use. CONCLUSIONS: The intake of OC significantly increases the lipid peroxidation in women aged 40-48 years. This may represent a potential cardiovascular risk factor for these women.


Assuntos
Anticoncepcionais Orais/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Adulto , Antioxidantes/análise , Doenças Cardiovasculares/etiologia , Cobre/sangue , Feminino , Humanos , Dispositivos Intrauterinos de Cobre , Dispositivos Intrauterinos Medicados , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/sangue , Lipoproteínas LDL/sangue , Lipoproteínas LDL/imunologia , Pessoa de Meia-Idade , Fatores de Risco , Selênio/sangue , beta Caroteno/sangue , gama-Tocoferol/sangue
10.
Vet J ; 174(1): 113-21, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17110141

RESUMO

The aim of this study was to investigate in a placebo-controlled field study the effect of a (n-3)-vitamin supplementation on erythrocyte membrane fluidity (EMF), oxidant/antioxidant markers and plasmatic omega3/omega6 fatty acid ratio (FAR) in 12 eventing horses. Venous blood was sampled at rest before (PRE) and after (POST) a three week treatment period with either the supplement (group S, n=6) or a placebo (group P, n=6) as well as after 15min (POST E15') and 24h (POST E24h) after a standardised exercise test. The following markers were analysed: EMF, plasma antioxidant capacity of water and lipid soluble components, ascorbic acid, uric acid (UA), glutathione (reduced: GSH, oxidised: GSSG), vitamin E (Vit E), beta-carotene, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity, selenium, copper (Cu), zinc (Zn), oxidised proteins (Protox), lipid peroxides (Pool) and FAR. EMF did not differ between group S and P after treatment, but GPx remained unchanged in group S whereas it decreased in group P and plasma Cu/Zn ratio remained unchanged whereas it increased in group P. FAR were significantly increased in group S. Exercise induced a significant decrease of EMF (POST vs. E24h) in both groups, but which was significantly lower at E15' in group S than in group P. Exercise induced a significant increase of UA and ACW (POST vs. E15') and Protox (POST vs. E24h) in both groups. An exercise-related decrease in GSH and Pool (POST vs. E15') was found in group P, whereas Vit E and FAR (POST vs. E24h) significantly decreased in both groups. The study showed that exercise induced a decrease in EMF in horses associated with changes of blood oxidative balance. The (omega-3)-vitamin supplementation tested improved the oxidative balance poorly but delayed the exercise-induced decrease of EMF and increased the FAR.


Assuntos
Antioxidantes/administração & dosagem , Membrana Eritrocítica/efeitos dos fármacos , Ácidos Graxos Ômega-3/administração & dosagem , Cavalos/sangue , Condicionamento Físico Animal , Animais , Suplementos Nutricionais , Membrana Eritrocítica/fisiologia , Ácidos Graxos Ômega-6/administração & dosagem , Feminino , Masculino
11.
Equine Vet J Suppl ; (36): 239-44, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17402425

RESUMO

REASONS FOR PERFORMING STUDY: There is increasing evidence that the equine athlete is exposed to exercise-induced changes of its oxidant/antioxidant balance and antioxidant supplementation is frequently recommended. However, it is unknown whether there is a specific need for antioxidants according to performance, breed, gender or age. OBJECTIVES: To assess whether breed-, gender- and age-related differences of blood oxidant/antioxidant markers occur in competition horses. METHODS: Healthy horses (n = 493) underwent oxidant/ antioxidant blood marker determination. Vitamin E, lipophilic antioxidant capacity (ACL), ascorbic acid (AA), glutathione (GSH, GSSG), gluthione peroxidase (GPx), superoxide dismutase (SOD), selenium (Se), copper (Cu), zinc (Zn), lipid peroxides (Pool), oxidised proteins (Protox) were determined, as well as magnesium (Mg), creatine phosphokinase (CPK), lactate dehydrogenase (LDH), packed cell volume (PCV) and haemoglobin (Hb). A mixed linear model assessed the effect of breed, gender and age category. P<0.05 was considered significant. RESULTS: Thoroughbreds showed the highest values of vitamin E, ACL, GPx, PCV and Hb, whilst standardbreds had the highest values of AA and LDH. Jumping horses had the highest Protox values. Females had significantly higher SOD values, whereas most of the other markers were higher in stallions and geldings. Horses age 2-6 years had higher AA, SOD and LDH values than horses age >6 years. Correlation analyses were positive and significant between vitamin E and GPx, VitE and ACL, Se and GPx, Cu and Pool and negative between Pool and vitamin E, Pool and ACL, Protox and GPx, Protox and vitamin E. CONCLUSIONS: Blood oxidant/ antioxidant status of horses is influenced by breed, gender and age. The correlation analyses suggest synergistic relations between GPx, vitamin E and Se and an antagonistic relation between Protox-GPx, Protox-vitamin E, and Pool-vitamin E. POTENTIAL RELEVANCE: The results of this investigation provide definition of the specific need for antioxidants and vitamins in competition horses.


Assuntos
Antioxidantes/metabolismo , Cavalos/sangue , Minerais/sangue , Vitaminas/sangue , Fatores Etários , Animais , Biomarcadores/sangue , Cruzamento , Feminino , Glutationa Peroxidase/sangue , Glutationa Peroxidase/metabolismo , Cavalos/metabolismo , Masculino , Minerais/metabolismo , Oxirredução , Selênio/sangue , Selênio/metabolismo , Fatores Sexuais , Vitamina E/sangue , Vitamina E/metabolismo , Vitaminas/metabolismo
12.
Equine Vet J Suppl ; (36): 254-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17402427

RESUMO

REASONS FOR PERFORMING STUDY: Interest in establishing oxidant/ antioxidant profiles in competition horses is increasing. Earlier studies performed in horses have mainly been performed under laboratory conditions using a treadmill and it is not known to what extent laboratory results of oxidant/antioxidant studies might be transposed to field conditions. OBJECTIVE: To compare the impact on the blood oxidant/ antioxidant status of a standardised exercise test including a run up to fatigue performed on a treadmill (TM) and on a racetrack (RT) in healthy and trained Standardbred horses. MATERIAL AND METHODS: During TM and RT tests the following blood antioxidant markers were analysed in jugular venous blood at rest and 15 mins (E15) after an intense bout of exercise: uric acid (UA), ascorbic acid (AA), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione (reduced: GSH and oxidised: GSSG), glutathione redox ratio (GRR) and protein thiol (PSH). Running time to fatigue (RTF), velocity during the last exercise stage (Vmax), final heart rate (HRfinal) and venous lactic acid (LA) were also recorded. RESULTS: Vmax was significantly (P<0.05) higher during the RT, whereas LA was significantly lower. HRfinal and RTF did not differ significantly between TM and RT. Exercise induced a significant increase (R vs. E15) of UA and AA in both tests, whereas GSH and PSH decreased significantly. GPx, SOD, GSSG and GRR remained unchanged. Differences between TM and RT were significant at E15 for UA, AA and PSH. CONCLUSIONS: Comparison of oxidant/antioxidant profiles from laboratory and field studies are difficult to standardise and should be interpreted with caution. POTENTIAL RELEVANCE: For the same RTF and final HR, the TM induced stronger changes in blood lactate and in blood oxidant/antioxidant balance than did RT.


Assuntos
Antioxidantes/metabolismo , Teste de Esforço/veterinária , Cavalos , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/fisiologia , Animais , Biomarcadores/sangue , Análise Química do Sangue/veterinária , Estudos Cross-Over , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Cavalos/sangue , Cavalos/fisiologia , Lactatos/sangue , Masculino , Oxirredução
13.
Transplant Proc ; 37(6): 2883-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16182842

RESUMO

The etiological mechanisms of brain edema in fulminant hepatic failure are incompletely understood. In a surgical model of fulminant hepatic failure in the rat, we tested whether oxidative stress may be involved in the early steps of brain edema. Moreover, we took advantage of this model to determine if oxidative stress may be involved in the hepatocyte dysfunction observed in the setting of fulminant hepatic failure. Oxidative stress was evaluated by measurement of tissue ascorbic acid in the brain and liver of rats at 6 hours after induction of fulminant hepatic failure versus in control or partially hepatectomized rats. After 6 hours, the level of ascorbic acid was not different in the brain tissue of the various groups, indicating no oxidative stress. The liver showed a significant decrease in ascorbic acid levels, both in ischemic and nonischemic liver tissue, suggesting that oxidative stress might be involved in the failure of liver regeneration in fulminant hepatic failure. In this rat model no oxidative stress was demonstrated in the brain during the early phase of fulminant liver failure.


Assuntos
Encéfalo/fisiopatologia , Falência Hepática Aguda/fisiopatologia , Fígado/fisiopatologia , Estresse Oxidativo/fisiologia , Animais , Ácido Ascórbico/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Hepatectomia , Isquemia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
14.
Vet J ; 169(1): 65-74, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15683765

RESUMO

The oxidant/antioxidant equilibrium of trained thoroughbred horses (n = 40) was assessed on three occasions during a period of three months under field conditions by blood antioxidant markers analysis, i.e. plasma ascorbic acid (AA), plasma antioxidant capacity of water-soluble components (ACW), whole blood (GSH) and oxidised (GSSG) glutathione, plasma alpha-tocopherol and beta-carotene, plasma antioxidant capacity of lipid-soluble components (ACL), red blood cell superoxide dismutase (SOD) and glutathione-peroxidase activity (GPx) and plasma trace-elements, i.e. selenium (Se), copper (Cu), zinc (Zn). A control group of ten horses receiving a placebo and an antioxidant group of 30 horses orally supplemented with an antioxidant mixture were randomly formed. An antioxidant imbalance was observed after three months in the control group, reflected by a significant decrease in GSH, SOD, GPx, Se (P < 0.05) and a significant increase in GSSG (P < 0.05). The antioxidant supplement prevented GPx and Se decrease and significantly increased ACW, alpha-tocopherol, beta-carotene and ACL (P < 0.05). Significant sex- or age-related differences were found for AA, ACW, alpha-tocopherol, SOD, GPx and Se, and there were significant correlations between ACW-AA, ACL-alpha-tocopherol, GPx-Se, CPK-Se, CPK-alpha-tocopherol and CPK-Cu. This field study has shown that trained thoroughbred horses undergo significant changes of several blood antioxidant markers and that oral antioxidant supplementation might partially counterbalance these changes by improving the hydrophilic, lipophilic and enzymatic antioxidant blood capacity.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Cavalos/sangue , Administração Oral , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Suplementos Nutricionais , Feminino , Glutationa/sangue , Glutationa/metabolismo , Glutationa Peroxidase/sangue , Glutationa Peroxidase/metabolismo , Cavalos/metabolismo , Masculino , Minerais/sangue , Minerais/metabolismo , Distribuição Aleatória , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo , Vitaminas/sangue , Vitaminas/metabolismo
17.
Perfusion ; 17(2): 117-23, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11958302

RESUMO

Intraoperative blood salvage devices allowing a reinfusion of red blood cells (RBCs) after processing of shed blood and stagnant blood in the mediastinal cavity are more and more used to reduce homologous blood requirements in cardiac surgery with cardiopulmonary bypass (CPB). As the proinflammatory activity of the shed blood also contributes to morbidity during CPB, we conducted a prospective study in order to examine the quality of autologous blood before and after processing with five different devices [BRAT2, Sequestra, Compact Advanced, Cell Saver 5 (CS5), Continuous Autologous Transfusion System (CATS)]. All systems resulted in an excellent haemoconcentration, ranging from 53.7% (Compact) to 68.9% (CATS). The concentrations and elimination rates of several inflammatory markers [IL-1beta, IL-2, IL-8, TNFalpha, myeloperoxidase (MPO), elastase] were examined. Except for the Sequestra, an important increase in concentration of IL-1beta (between 30% and 220%) has been observed after processing with each device. In contrast, the attenuation rate of IL-6 and TNFalpha (95%) was optimal for all investigated blood salvages systems. Regarding IL-8, only the CATS and CS5 systems were able to attenuate this biological parameter with an excellent efficacy. The rate of attenuation in MPO and elastase, as markers of leukocyte activation, was higher than 80% for all devices. In conclusion, the different RBC washing systems tested in this study resulted in a significant attenuation of the inflammatory response. Increased levels of IL-1beta after processing remained, however, unclear. According to the type of protocol, based on inlet haematocrit, fill and wash speeds, and wash volumes, small variations in reducing the inflammatory response have been observed from one device to another.


Assuntos
Transfusão de Sangue Autóloga/instrumentação , Ponte Cardiopulmonar/efeitos adversos , Inflamação/sangue , Idoso , Biomarcadores/sangue , Remoção de Componentes Sanguíneos/instrumentação , Remoção de Componentes Sanguíneos/normas , Transfusão de Sangue Autóloga/normas , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Citocinas/sangue , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/sangue , Peroxidase/sangue
18.
Ann Thorac Surg ; 69(4): 1084-91, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10800798

RESUMO

BACKGROUND: Cardiopulmonary bypass (CPB) initiates a whole-body inflammatory response where complement and neutrophil activation and cytokine release play an important role. This prospective trial examined the effects of both heparin-coated circuits and aprotinin on the inflammatory processes during CPB, with respect to cytokine release and neutrophil activation. METHODS: Two hundred patients undergoing cardiac surgery were randomized in four groups of 50 patients each: heparin-coated circuit with aprotinin (HCO-A) or without aprotinin (HCO) administration, and uncoated circuit with aprotinin (C-A) or without aprotinin administration (C). In groups receiving aprotinin, a high-dose regimen was given. In all groups, high initial doses of heparin were used (3 mg/kg intravenously). Tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-8, and myeloperoxidase and elastase levels were measured in plasma samples taken before, during, and after CPB. RESULTS: In all groups, the TNF-alpha, IL-6, and IL-8 levels reached a maximum after protamine administration. After 24 hours, they remained significantly elevated (IL-6 and IL-8) or returned to baseline values (TNF-alpha). A similar pattern was observed with myeloperoxidase and elastase levels. No significant intergroup differences were observed. CONCLUSIONS: CPB is associated with cytokine release and neutrophil activation, which are not attenuated by the use of heparin-coated circuits or by the administration of aprotinin. Aprotinin and heparin-coated circuits do not show additive effects.


Assuntos
Ponte Cardiopulmonar , Materiais Revestidos Biocompatíveis , Citocinas/sangue , Fibrinolíticos/uso terapêutico , Heparina/uso terapêutico , Ativação de Neutrófilo , Aprotinina/uso terapêutico , Feminino , Hemostáticos/uso terapêutico , Humanos , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/análise
19.
Ann Biol Clin (Paris) ; 58(2): 177-85, 2000.
Artigo em Francês | MEDLINE | ID: mdl-10760704

RESUMO

A large number of epidemiological and clinical studies suggest that oxidative stress plays an important role in the development of cardiovascular diseases. In this way, following reference values in plasmatic antioxidants have been determined in a group of 123 blood donors (94 males, 29 females; age: 21-64 years) living in the surroundings of Liege, Belgium: vitamin A (1.5-3.62 mmol/l), vitamin C (3.68-75.21 mmol/l), vitamin E (16.98-46.46 mmol/l), ratio vitamin E/cholesterol (3.92-8.32 mmol/mmol), selenium (0.66-1.26 mmol/l), sulphydryl proteins (216-556 mmol/l), uric acid (174-477 mmol/l), superoxide dismutase (542-852 IU/g hemoglobine), glutathion peroxidase (39.55-91.83 IU/g hemoglobine). Only a few number of subjects were found with values corresponding to high risk of deficiency in antioxidants although low values in vitamin C (< 11.35 mmol/l) and in selenium (< 0.75 mmol/l) were respectively observed in 5.69 and 10.5% of our subjects. Autoantibodies against oxidized LDL, as marker of oxidative stress, and homocysteine, as a risk factor of atherosclerosis involved in the development of oxidative stress, have also been investigated. Approximatively 40% of the population presented values higher than the superior limit mean value (20.3% > 650 IU/l in autoantibodies and 19.5% > 15.2 mmol/l in homocysteine) that are, however, not correlated with age or low levels in antioxidants. The effect of smoking (25% of the population) contributed to significantly decrease vitamin C, selenium and glutathion peroxidase concentrations by 31.9 and 13% when compared to nonsmokers. Intake of 1 to 4 fruits per day resulted in a significant increase of 56.9% in vitamin C when compared to nonconsumers (26.8% of the population). In contrast, homocysteine concentrations were significantly decreased by 21.4% in fruits consumers. Thank to the development of methods allowing the routine dosage of all these parameters, general practitioners can now easily establish the oxidative stress status of their patients and, as fonction of getting patterns, detect populations at risk of developing cardiovascular diseases.


Assuntos
Ácido Ascórbico/sangue , Autoanticorpos/sangue , LDL-Colesterol/imunologia , Homocisteína/sangue , Vitamina A/sangue , Vitamina E/sangue , Adulto , LDL-Colesterol/metabolismo , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução
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