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Antioxidant Supplementation (antioxidant + supplementation)
Selected AbstractsInfluence of Ascorbic Acid and Glutathione Antioxidants on Frozen-Thawed Canine SemenREPRODUCTION IN DOMESTIC ANIMALS, Issue 2009JC Monteiro Contents Poor sperm viability post-thaw has resulted in constant research into methods of cryopreservation of canine semen. One factor that may be involved in poor viability is sperm oxidative stress caused by excessive formation of reactive oxygen species. The present study was performed in order to evaluate the effect of different concentrations of ascorbic acid (AA) and glutathione (Glu) added to an extender for the freeze-thawing of dog sperm. Semen from five mature dogs was collected and frozen in two studies. Prior to and after freezing, sperm motility, morphology and membrane status were examined. In addition, sperm motility was examined up to 120 min after thawing to evaluate thermo-resistance. In study I, semen was collected twice from each dog. On both occasions, semen was divided into three aliquots: control, Glu 1 mm and Glu 5 mm. In study II, semen was collected twice and divided into three aliquots; control, AA 50 ,m and AA 250 ,m. Initial sperm motility was significantly higher in sperm diluted with AA 50 ,m; sperm longevity, however, measured by a thermal-resistance test (TRT), was higher for Glu treatments. Higher concentration of Glu produced significant improvement in TRT and membrane status, whereas higher concentration of AA had a negative impact in sperm longevity. Antioxidant supplementation to semen freezing extenders improved semen quality post-thaw. Moreover, Glu had the most beneficial effect when supplemented at 5 mm. [source] Oxidant/antioxidant status and vitamin A levels in children infected with varicellaACTA PAEDIATRICA, Issue 7 2008Zekai Avci Abstract Aim: Varicella is a childhood disease, with its highest incidence being found in children aged 1 to 9 years. The aim of this study was to investigate the plasma oxidant and antioxidant status in Turkish children with varicella infection. Methods: The study population consisted of 29 children infected with varicella recruited from the Department of Pediatrics at Baskent University Hospital in Ankara, Turkey. The control group consisted of 20 age-matched children from the same region who were apparently otherwise healthy. After overnight fasting, venous blood samples were obtained and transferred to heparinized tubes. Plasma malondialdehyde and vitamin A levels were measured in both groups. Results: The plasma malondialdehyde levels were higher in children in the infected group than they were in children in the control group. However, there were no statistically significant differences in plasma vitamin A levels between the groups. Conclusion: This study suggests that oxidant stress causes significant peroxidation, and the antioxidant defence system is affected in varicella infection. Antioxidant supplementation may yield beneficial results in these patients. Further studies are needed to determine the positive effects of vitamin A supplementation in patients with varicella infections. [source] Antioxidant supplementation and nasal inflammatory responses among young asthmatics exposed to high levels of ozoneCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 2 2004J. J. SIENRA-MONGE SUMMARY The inflammatory response to ozone in atopic asthma suggests that soluble mediators of inflammation are released in response to oxidant stress. Antioxidants may alleviate additional oxidative stress associated with photochemical oxidant pollution. This study investigates the impact of antioxidant supplementation on the nasal inflammatory response to ozone exposure in atopic asthmatic children. We conducted a randomized trial using a double-blinded design. Children with asthma (n = 117), residents of Mexico City, were given randomly a daily supplement of vitamins (50 mg/day of vitamin E and 250 mg/day of vitamin C) or placebo. Nasal lavages were performed three times during the 4-month follow-up and analysed for content of interleukin-6 (IL-6), IL-8, uric acid and glutathione (GSx). IL-6 levels in the nasal lavage were increased significantly in the placebo group after ozone exposure while no increase was observed in the supplement group. The difference in response to ozone exposure between the two groups was significant (P = 0·02). Results were similar for IL-8, but with no significant difference between the groups (P = 0·12). GSx decreased significantly in both groups. Uric acid decreased slightly in the placebo group. Our data suggest that vitamin C and E supplementation above the minimum dietary requirement in asthmatic children with a low intake of vitamin E might provide some protection against the nasal acute inflammatory response to ozone. [source] Is oxidative stress involved in the aetiology of pre-eclampsia?ACTA PAEDIATRICA, Issue 2001L Poston Pre-eclampsia is one of the major indications for elective premature delivery. Several lines of evidence suggest that pre-eclampsia is associated with a state of oxidative stress, offering hope of prevention by antioxidant supplementation. It was recently shown by the present authors that supplementation with vitamin C and E from early in pregnancy leads to a reduction in the incidence of the disease in "high-risk" women. [source] Antioxidant and inflammatory responses of healthy horses and horses affected by recurrent airway obstruction to inhaled ozoneEQUINE VETERINARY JOURNAL, Issue 3 2005C. M. DEATON Summary Reasons for performing study: Inhaled ozone can induce oxidative injury and airway inflammation. Horses affected by recurrent airway obstruction (RAO) have a decreased pulmonary antioxidant capacity, which may render them more susceptible to oxidative challenge. It is currently unknown whether RAO-affected horses are more susceptible to oxidative stress than those unaffected by RAO. Objectives: To determine whether ozone exposure induces greater oxidative stress and airway inflammation in RAO-affected horses in remission than in healthy horses. Methods: Seven healthy control horses and 7 RAO-affected horses were exposed to 0.8 ppm ozone for 2 h at rest. Results: At baseline, bronchoalveolar lavage fluid (BALF) ascorbic acid concentrations were lower in RAO-affected horses than healthy controls. Ozone appeared to preferentially oxidise glutathione rather than ascorbic acid 6 h after exposure. Individual healthy and RAO-affected horses demonstrated oxidation of BALF glutathione after ozone exposure. Overall, RAO-affected horses did not demonstrate increased oxidative stress following ozone exposure, compared with healthy horses. Ozone did not induce significant airway inflammation in either group. Conclusions: RAO-affected horses in remission are not more sensitive to ozone despite a decreased pulmonary antioxidant capacity. Sensitivity to ozone appears to be independent of initial pulmonary antioxidant status. Potential relevance: Horses with high susceptibility to oxidative stress may benefit from antioxidant supplementation. [source] The relationship between obesity and markers of oxidative stress in dogsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 2 2009M. G. Cline Obesity, a serious epidemic affecting much of our pet population, increases the risk of developing numerous diseases. It has been demonstrated that obesity increases oxidative stress in obese children, cats and other species. Oxidative stress can result in DNA damage with subsequent alterations in gene expression, cell signaling, mutations, cell death or cell transformation. These effects of oxidative damage predispose animals and humans to numerous disease processes and cancer. The objective of the study was to demonstrate that obese dogs are under oxidative stress resulting in DNA damage and decreased endogenous antioxidant protection measured by serum glutathione levels and the ratio of reduced (GSH) to oxidized (GSSG) glutathione. In this case,control study, 10 obese dogs were compared with aged-matched healthy control dogs. Dogs with BCS of 7 or greater (9 pt scale) were considered obese. Dogs were evaluated by history, physical exam, body condition score, CBC, serum biochemical analysis and total T4, with both groups showing no significant differences in CBC, serum biochemical or T4 analysis. Single-cell gel electrophoresis (Comet assay) was used to measure DNA damage, and high performance liquid chromatography was used to measure serum glutathione. Reduced glutathione levels were significantly higher in the obese group (p = 0.012). The results of this pilot study suggest that obesity is associated with an increase in antioxidant potential, therefore justifying a larger study with antioxidant supplementation to determine how antioxidants in weight loss diets effects endogenous antioxidant capabilities. [source] Protective effects of cysteine, methionine and vitamin C on the stomach in chronically alcohol treated ratsJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2008Ramazan Amanvermez Abstract A chronic intake of high dose alcohol may cause oxidative stress and inflammation in the stomach. It is hypothesized that cysteine-methionine and vitamin C may neutralize harmful compounds while potentiating the antioxidant capacity of the cell or tissue. The experimental animals were fed regular diets and were maintained for 90 days in the control group, the alcoholic group, which was given 2.5 g of 50% ethanol kg,1 body wt. administered intragastrically every other day, or the alcoholic with antioxidant supplement group, to whom 2.5 g of 50% ethanol kg,1 body wt. + a solution that contained 200 mg vitamin C, 100 mg cysteine and 100 mg methionine was administered intragastrically every other day. After the treatments, the stomach was taken for pathological and biochemical analysis. The stomach of the alcoholic group rats had higher scores of pathological findings compared with the control group, whereas the scores of the antioxidant-supplemented group were lower than the alcoholic group. In addition, the oxidized protein and lipid content in the stomachs of the alcoholic group were significantly higher than the control, but antioxidant supplementation lowered the amount of oxidation in the antioxidant supplemented group. The amount of stomach glutathione in the alcoholic group was higher than that of the control and antioxidant-supplemented groups. Interestingly, the level of total thiol in the stomach tissue of rats with antioxidant supplement was statistically higher than that of the control and alcoholic groups. In conclusion, the scores of the pathological findings in the stomach of rats with the antioxidant supplement were lower than the chronic alcohol-treated rats, albeit the amount of total thiol was increased in this group. Moreover, chronic alcohol treatment led to an increase in the level of lipid and protein oxidation in the stomach tissue of rats. A simultaneous intake of ascorbate/l -cys/l -met along with ethanol attenuated the amount of oxidation which suggested that cysteine-methionine and vitamin C could play a protective role in the stomach against oxidative damage resulting from chronic alcohol ingestion. Copyright © 2007 John Wiley & Sons, Ltd. [source] Protective effect of vitamin E on ultraviolet B light,induced damage in keratinocytesMOLECULAR CARCINOGENESIS, Issue 3 2002Samar Maalouf Abstract Ultraviolet (UV) B radiation is the most common environmental factor in the pathogenesis of skin cancer. Exposure of human skin to UVB radiation leads to the depletion of cutaneous antioxidants, the activation of nuclear factor kappa B (NF-,B), and programmed cell death (apoptosis). Although antioxidant supplementation has been shown to prevent UVB-induced photooxidative damage, its effect on components of cell signaling pathways leading to gene expression has not been clearly established. In the present study, the effect of the antioxidant vitamin, ,-tocopherol (,-T), and its acetate analog, ,-tocopherol acetate (,-TAc), on UVB-induced damage in primary and neoplastic mouse keratinocytes was investigated. The ability of both vitamins to modulate UVB-induced apoptosis and activation of the transcription factor NF-,B were studied. Treatment of normal and neoplastic mouse epidermal keratinocytes (308 cells) with 30,60 mJ/cm2 UVB markedly decreased viable cell number and was accompanied by DNA fragmentation. When both vitamins were applied to cells at times before and after UVB radiation, a significant increase in the percentage of viable cells and concomitant decrease in the number of apoptotic cells was noted, with vitamin pretreatment providing a better protection than posttreatment. Simultaneous posttreatment of irradiated cells with ,-TAc abolished the cytotoxic effects of UVB and restored cell viability to control levels. In addition, simultaneous posttreatment of irradiated cells with ,-T reduced the number of apoptotic cells by half, indicating a synergistic effect of two such treatments compared with any single one. Flow cytometry analysis indicated that vitamin treatment suppressed both an increase in pre-G0 cells and a decrease in cycling cells by UVB exposure. In addition, NF-,B activation was detected 2 h after UV exposure and was maintained for up to 8 h. Pretreatment with vitamins significantly inhibited NF-,B activation at 4 and 8 h. These results indicate that vitamin E and its acetate analog can modulate the cellular response to UVB partly through their action on NF-,B activation. Thus, these antioxidant vitamins are potential drugs for the protection from or the reduction of UVB-associated epidermal damage. © 2002 Wiley-Liss, Inc. [source] Antioxidant Requirements of Endurance Athletes: Implications for HealthNUTRITION REVIEWS, Issue 3 2006Sarah L. Williams BSc (Hons) This review discusses studies investigating the effects of antioxidant supplementation on exercise-induced oxidative stress with a focus on the health implications. The aim is to determine antioxidant requirements for endurance athletes. Overall, differences in methodology make it difficult to compare the relatively small number of published studies on this topic. The types of studies needed to more adequately assess the health effects of antioxidant supplements in athletes (long-term interventions with hard end points) have not been done. Therefore, there is currently insufficient evidence to recommend antioxidant supplements for endurance athletes. [source] Short-term antioxidant supplementation reduces oxidative stress in elderly patients with type 2 diabetes mellitus,a pilot studyPRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 7 2002SL Nuttall PhD Research Fellow Abstract Aims The aim of this pilot study was to determine what dose of which antioxidants might be studied in clinical trials by assessing the impact of vitamin (C and E) supplementation on markers of oxidative stress and LDL subfractions in patients with type 2 diabetes mellitus. Methods Nine elderly patients with type 2 diabetes took a moderate dose combination of vitamins C (500 mg) and E (400 IU) for 4 weeks. Following a 4 week washout, the patients had a further 4 weeks of supplementation with a higher dose combination of vitamins C (1000 mg) and E (800 IU). Blood was sampled pre- and post-supplementation for vitamin E by high-performance liquid chromatography (HPLC), total antioxidant capacity by enhanced chemiluminescence, total cholesterol and lipid hydroperoxides by colour spectrophotometry and LDL subfraction profile by disc polyacrylamide gel electrophoresis. Results Vitamin E was increased, after the moderate dose combination (59.8 ± 6 versus 36.4 ± 4 µmol/L, p < 0.001) and increased further by the higher dose (72.7 ± 11 versus 30.8 ± 5 µmol/L, p < 0.001). Total antioxidant capacity was significantly increased above baseline after both doses (508.2 ± 33 versus 436.4 ± 31, p < 0.01 (moderate); 519.3 ± 48 versus 440.8 ± 34 µmol/L trolox eq., p < 0.01 (high)). Lipid hydroperoxides were reduced more after the moderate dose combination than after the high dose (6.1 ± 1 versus 12.1 ± 2, p < 0.01; 8.0 ± 1 versus 11.6 ± 1 µmol/L, p < 0.05). LDL subfraction score showed a non-significant reduction after both periods of supplementation. Conclusions This study has demonstrated that supplementation with modest doses of the antioxidant vitamins C and E can significantly increase antioxidant defences and reduce oxidative damage in elderly patients with type 2 diabetes. Copyright © 2002 John Wiley & Sons, Ltd. [source] Reduction of Oxidative Stress in Bovine Spermatozoa During Flow Cytometric SortingREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2007P Klinc Contents The goal of the study was to investigate the effect of antioxidant supplementation on the quality of frozen-thawed flow cytometrically sorted bull spermatozoa. Twelve ejaculates from two Holstein Friesian bulls were sorted according to the Beltsville Sperm Sexing Technology. Each ejaculate was divided into three parts and processed as (i) unsorted controls, (ii) according to a standard sorting protocol and (iii) in the presence of different antioxidants (S-AO). Cooling and freezing of the samples were performed in the same way for all three groups, except that antioxidants were added to the TRIS-egg-yolk freezing extender for those semen samples that were already sorted in the presence of antioxidants. The semen quality in frozen-thawed samples was determined by morphology analysis immediately after thawing, motility estimation in a thermo-resistance test after 0, 6, 12 and 24 h incubation at 37°C and Fluorescein isothiocyanate conjugated PNA/propidium iodide (FITC-PNA/PI) staining after 0, 12 and 24 h of incubation at 37°C. There was a significantly higher (p < 0.05) percentage of motile spermatozoa in S-AO samples in comparison to unsorted frozen-thawed control at 0, 6 and 24 h after thawing and compared with normally sorted samples at all times after thawing. The percentage of damaged acrosomes was significantly lower (p < 0.05) in S-AO samples than in the unsorted controls (20.8 ± 6.9% vs 30.3 ± 12.0%). The percentage of morphologically abnormal spermatozoa in this group was significantly lower (p < 0.05) than in the unsorted controls and normally sorted samples (25.8 ± 5.2%, 36.0 ± 12.5% and 35.1 ± 7.4%, respectively). Analysis of frozen-thawed spermatozoa with FITC/PI revealed no significant difference in membrane integrity at 0 and 12 h after sorting, but after 24 h of incubation the S-AO samples had a significantly higher (p < 0.001) percentage of spermatozoa with intact membranes in comparison to unsorted controls and normally sorted semen (40.7 ± 6.3%, 7.8 ± 4.7% and 7.4 ± 4.6%, respectively). The percentage of acrosome-reacted spermatozoa was significantly lower (p < 0.05) in the S-AO samples than in the unsorted controls (14.1 ± 7.5%, 23.4 ± 5.4% and 28.8 ± 6.3% vs 25.9 ± 14.4%, 38.5 ± 16.7% and 79.8 ± 4.1%, for 0, 12 and 24 h after thawing, respectively) and in comparison to normally sorted semen 24 h after thawing (67.3 ± 10.0%). This study demonstrates the highly protective effects of antioxidants on the quality of flow cytometrically sorted frozen-thawed bull spermatozoa. [source] Serum iron and copper status and oxidative stress in severe and mild preeclampsiaCELL BIOCHEMISTRY AND FUNCTION, Issue 3 2006Zehra Serdar Abstract Our aim was to investigate parameters of iron and copper status and oxidative stress and antioxidant function in women with healthy pregnancy, mild and severe preeclampsia with a view to exploring the possible contribution of these parameters to the aetiology. Thirty healthy, 30 mild preeclamptic and 30 severe preeclamptic pregnant women were included. Serum and placental lipid peroxides, and serum vitamin E and total carotene levels were measured by colorimetric assay. Cholesterol, copper, iron, total iron binding capacity (TIBC), ceruloplasmin and transferrin concentrations were measured by commercially available procedures. Data were analysed statistically using one-way analysis of variance and Pearson correlation test. Logistic regression procedures were used to calculate odds ratios. Lipid peroxides in serum and placental tissue, and iron, copper and ceruloplasmin levels in serum were significantly increased, and transferrin, TIBC, vitamin E/total cholesterol and total carotene/total cholesterol ratios in serum were significantly decreased especially in women with severe preeclampsia. Significant correlations were detected between serum iron and lipid peroxidesin serum and placental tissue and between serum iron and vitamin E/total cholesterol in severe preeclamptic pregnancy. Furthermore, there were significant correlations between serum malondialdehyde and ceruloplasmin and vitamin E/total cholesterol in women with severe preeclampsia, and changes in serum and placental lipid peroxides and serumiron concentrations were significantly associated with preeclampsia. In conclusion, ischaemic placental tissue may be a primary source of potentially toxic iron in preeclampsia and the released iron species may contribute to the aetiology and would exacerbatelipid peroxidation and endothelial cell injury, which may be abated by antioxidant supplementation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Antioxidant supplementation and nasal inflammatory responses among young asthmatics exposed to high levels of ozoneCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 2 2004J. J. SIENRA-MONGE SUMMARY The inflammatory response to ozone in atopic asthma suggests that soluble mediators of inflammation are released in response to oxidant stress. Antioxidants may alleviate additional oxidative stress associated with photochemical oxidant pollution. This study investigates the impact of antioxidant supplementation on the nasal inflammatory response to ozone exposure in atopic asthmatic children. We conducted a randomized trial using a double-blinded design. Children with asthma (n = 117), residents of Mexico City, were given randomly a daily supplement of vitamins (50 mg/day of vitamin E and 250 mg/day of vitamin C) or placebo. Nasal lavages were performed three times during the 4-month follow-up and analysed for content of interleukin-6 (IL-6), IL-8, uric acid and glutathione (GSx). IL-6 levels in the nasal lavage were increased significantly in the placebo group after ozone exposure while no increase was observed in the supplement group. The difference in response to ozone exposure between the two groups was significant (P = 0·02). Results were similar for IL-8, but with no significant difference between the groups (P = 0·12). GSx decreased significantly in both groups. Uric acid decreased slightly in the placebo group. Our data suggest that vitamin C and E supplementation above the minimum dietary requirement in asthmatic children with a low intake of vitamin E might provide some protection against the nasal acute inflammatory response to ozone. [source] | |||||||||||||