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Total Glutathione (total + glutathione)
Selected AbstractsThermally oxidized palm olein exposure increases triglyceride polymer levels in rat small intestineEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2010Raul Olivero David Abstract The origin and presence of triglyceride polymers in small intestine have been poorly studied. The present study combined a short in vivo absorption experiment and high-performance size-exclusion chromatography determination. Groups of six male Wistar rats were administered by esophageal probe 1,g/100,g body weight unused palm olein and palm oleins used in 40 and 90 potato frying operations. Small intestines were dissected, cleaned of luminal fat, and analyzed for the presence of triglyceride polymers (oligomers and/or dimers) after 4,h oil administration. The intestinal fat content did not change but the polymers content was positively and significantly correlated (r,=,0.5983; p<0.01) with the amount of polymers present in the oil tested. The small intestine contained 5.05,mg [median and percentile 25 (1.57,mg),percentile 75 (10.40,mg)] of polymers after 4-h exposure to palm olein used for frying 90 times. The results suggested that 2.7,4.9% of the triglyceride polymers administered were present in the small intestine 4,h after ingestion. TBARS levels (p<0.05) and the redox index (oxidized glutathione/total glutathione) (p<0.01) in the small intestine increased significantly after exposure to the palm olein used in 90 frying operations. In conclusion, administration of altered oil increased the presence of resynthesized polymers in the small intestine, thus contributing to small intestine oxidative stress. [source] Response of the freshwater alga Chlorella vulgaris to trichloroisocyanuric acid and ciprofloxacin,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2008Xiangping Nie Abstract The effects of trichloroisocyanuric acid (TCCA) and ciprofloxacin (CPFX) on the freshwater alga Chlorella vulgaris were assessed by toxicity bioassays and by the values of biomarkers in phase I and phase II. The biomarkers included growth rate, concentration of chlorophyll a, activities of 7-ethoxyresorufin- O -dealkylases (EROD), glutathione S -transferase (GST), catalase (CAT), and total glutathione (GSH). Ciprofloxacin was a weaker growth inhibitor than TCCA but, at a concentration of greater than 12.5 mg/L, decreased the growth of C. vulgaris. Concentration of chlorophyll a showed a similar trend. The 96-h median effective concentration (EC50; i.e., 50% reduction in growth relative to the control) of CPFX was 20.6 mg/L. Trichloroisocyanuric acid was a strong growth inhibitor and, at concentrations of greater than 0.80 mg/L, caused 100% inhibition on 24-h exposure. The 96-h EC50 of TCCA was 0.313 mg/L. Ciprofloxacin and TCCA affected the phase I and phase II enzyme activities differently. On exposure to CPFX, both EROD and GSH decreased at low CPFX concentrations (<5.0 mg/L) and increased at high CPFX concentrations (>12.5 mg/L), and CAT and GST exhibited induction at low concentrations and inhibition at high concentrations. In TCCA exposure, GST activity was significantly stimulated, and GSH concentration was increased. Catalase activity increased only at TCCA concentrations of greater than 0.12 mg/L, and no change in EROD activity was observed. [source] Oral vitamin E supplementation on oxidative stress, vitamin and antioxidant status in intensely exercised horsesEQUINE VETERINARY JOURNAL, Issue S36 2006C. A. WILLIAMS Summary Reasons for performing study: Vitamin E is the most commonly supplemented antioxidant in horses; however, previous research is not conclusive as to the recommended level for exercising horses. Objective: To evaluate the effects of 3 levels of vitamin E supplementation on oxidative stress and vitamin/antioxidant status in intensely exercised horses to determine the optimal level of vitamin E supplementation. Methods: Twelve unfit Standardbreds were divided into 3 groups, supplemented orally with 0 (CON), 5000 (MOD), or 10,000 (HI) iu/day of DL-,-tocopheryl acetate. The 3 times 3 Latin square design consisted of three 4 week supplementation periods with 4 week wash out periods between. After each period, horses underwent a treadmill interval exercise test. Blood samples were collected and heart rate (HR) measured before, during and after exercise. Data were analysed using ANOVA with repeated measures in SAS. Results: The CON group had lower HR throughout the test compared to the MOD and HI groups (P<0.05). There was an increase in plasma retinol (RET), ,-carotene (BC), red blood cell total glutathione and glutathione peroxidase with exercise (P<0.05), but all groups returned to baseline after 24 h. Plasma ,-tocopherol (TOC) increased from baseline with exercise (P<0.0001) in all groups; treatment differences were observed at 24 h (P<0.05). The HI and CON groups had lower BC compared to the MOD group (P = 0.05). Conclusions: Horses supplemented with vitamin E, at nearly 10-times the 1989 NRC recommended level, did not experience lower oxidative stress compared to control horses. Additionally, lower plasma BC levels observed in the HI group, which may indicate that vitamin E has an inhibitory effect on BC metabolism. Potential relevance: Supplementation above control levels is not more beneficial to oxidative stress and antioxidant status in intensely exercising horses; indeed, levels 10 times in excess may be detrimental to BC and should be avoided. [source] Changes in oxidative balance in rat pericytes exposed to diabetic conditionsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2004A. Manea Abstract Recent data indicate that the oxidative stress plays an important role in the pathogenesis of diabetes and its complications such as retinopathy, nephropathy and accelerated atherosclerosis. In diabetic retinopathy, it was demonstrated a selective loss of pericytes accompanied by capillary basement membrane thickening, increased permeability and neovascularization. This study was designed to investigate the role of diabetic conditions such as high glucose, AGE-Lysine, and angiotensin II in the modulation of antioxidant enzymes activities, glutathione level and reactive oxygen species (ROS) production in pericytes. The activity of antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and total glutathione (GSH) was measured spectrophotometrically. The production of ROS was detected by spectrofluorimetry and fluorescence microscopy after loading the cells with 2,-7, dichlorofluoresceine diacetate; as positive control H2O2 was used. Intracellular calcium was determined using Fura 2 AM assay. The results showed that the cells cultured in high glucose alone, do not exhibit major changes in the antioxidant enzyme activities. The presence of AGE-Lys or Ang II induced the increase of SOD activity. Their combination decreased significantly GPx activity and GSH level. Athree times increase in ROS production and a significant impairment of intracellular calcium homeostasis was detected in cells cultured in the presence of the three pro-diabetic agents used. In conclusion, our data indicate that diabetic conditions induce in pericytes: (i) an increase of ROS and SOD activity, (ii) a decrease in GPx activity and GSH level, (iii) a major perturbation of the intracellular calcium homeostasis. The data may explain the structural and functional abnormalities of pericytes characteristic for diabetic retinopathy. [source] Matrix metalloproteinases, IL-8 and glutathione in the prognosis of workers exposed to chlorineALLERGY, Issue 6 2010K. Maghni To cite this article: Maghni K, Malo J-L, L'Archevêque J, Castellanos L, Gautrin D. Matrix metalloproteinases, IL-8 and glutathione in the prognosis of workers exposed to chlorine. Allergy 2010; 65: 722,730. Abstract Background:, Workers exposed to chlorine may be at risk of deterioration in FEV1. Methods:, A prospective study of 72 workers examined over a 5.8 ± 1.9 year period. A sample of induced sputum for cells and mediators was obtained in 69 subjects at baseline (Vb) and in 36 both at Vb and at follow-up (Vf). Results:, Sixty-four workers (89%) experienced at least one accidental inhalation of chlorine in the interval. The mean decrease in FEV1 was 30 ml/year and thus was within normal limits. Among the analysed remodelling markers, the level of the MMP-9-TIMP-1 complex, but not of free MMP-9 and TIMP-1, significantly diminished from Vb to Vf. We found significant correlations between neutrophils, IL-8, MMP-9 and MMP9-TIMP-1 complex at Vb and Vf. While levels of total glutathione, IL-8, MMP9, TIMP-1 and MMP9-TIMP-1 complex were highly correlated with each other at Vb, this was inconstant at Vf. Levels of MMP9-TIMP1 complex and of TIMP1 at Vf were significantly lower in workers reporting chlorine puffs with mild acute respiratory symptoms between visits compared to those who had no, or asymptomatic inhalations (P = 0.03 and 0.02, respectively). The fall in FEV1 from Vb to Vf was significantly correlated with levels of glutathione at Vb. Cough between visits was associated with a decrease in FEV1 (P = 0.06). Conclusion:, Although no accelerated loss in FEV1 was documented in these workers exposed to chlorine, subjects with a greater fall in FEV1 were more likely to report cough and have higher levels of total glutathione at Vb. [source] Copper accumulation, synthesis of ascorbate and activation of ascorbate peroxidase in Enteromorpha compressa (L.) Grev. (Chlorophyta) from heavy metal-enriched environments in northern ChilePLANT CELL & ENVIRONMENT, Issue 10 2003N. RATKEVICIUS ABSTRACT Enteromorpha compressa is the dominant species in coastal areas of northern Chile receiving copper mine wastes. Copper remains as the main heavy metal in these coastal waters and it is accumulated in E. compressa growing at the impacted sites. Algae from these sites showed higher levels of lipoperoxides than from non-impacted sites, which suggests the occurrence of cellular damage resulting from oxidative stress. The strong activation of ascorbate peroxidase detected in this study probably occurs in order to buffer this oxidative stress. Unexpectedly, the activity of glutathione reductase, normally coupled to ascorbate peroxidase activity, was not affected by the chronic exposure to the mine wastes. Moreover, catalase, dehydroascorbate reductase and glutathione peroxidase, commonly reported to buffer oxidative stress in plants and algae, were not detected in E. compressa from any of the studied sites. Levels of total glutathione and phenolic compounds decreased in algae from mine-impacted sites. In contrast, high levels of dehydroascorbate were found in algae from impacted sites, whereas ascorbate remained unchanged. Therefore, it is suggested that E. compressa tolerates a copper-enriched environment, and the accompanying oxidative stress, through the accumulation of copper, activation of ascorbate peroxidase, synthesis of ascorbate (accumulated as dehydroascorbate) and consumption of glutathione and water-soluble phenolic compounds. [source] Protective Effect of Sesamol against 3-Nitropropionic Acid-Induced Cognitive Dysfunction and Altered Glutathione Redox Balance in RatsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 1 2010Puneet Kumar It is a well-known antioxidant, currently being tried against several neurological disorders. The present study was designed to evaluate the potential of sesamol treatment against 3-nitropropionic acid (3-NP)-induced cognitive impairment and oxidative damage in striatal, cortex and hippocampal regions of the rat. The memory performance was assessed by Morris water maze and elevated plus maze paradigms. The oxidative damage was assessed by estimating the total glutathione, reduced glutathione, oxidized glutathione levels and glutathione redox ratio. Glutathione- S -transferase and lactate dehydrogenase enzymes were also measured in different brain areas. 3-NP significantly impaired memory performance as assessed in Morris water maze and elevated plus maze, which was significantly attenuated by sesamol (5, 10 and 20 mg/kg) pre-treatment. On the other hand, 3-NP significantly induced oxidative stress and depleted total glutathione, reduced glutathione, glutathione- S -transferase, lactate dehydrogenase enzyme levels and redox ratio in the striatum, cortex and hippocampal regions as compared to the vehicle-treated group. Sesamol pre-treatment restored oxidative defence possibly by its free radical scavenging activity as compared to the 3NP-treated group. The present study suggests that sesamol could be used as an effective agent in the management of Huntington's disease. [source] Glutathione cycle in stable chronic obstructive pulmonary diseaseCELL BIOCHEMISTRY AND FUNCTION, Issue 6 2010Biljak, Vanja Radi Abstract Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation and oxidant/antioxidant imbalance. Glutathione is the most abundant cellular low-molecular weight thiol and the glutathione redox cycle is the fundamental component of the cellular antioxidant defence system. Concentration of total glutathione and catalytic activities of glutathione peroxidase and glutathione reductase were determined in peripheral blood of patients (n,=,109) and healthy subjects (n,=,51). Concentration of total glutathione in patients was not changed in comparison to healthy controls. However, we found statistically significant difference between patients with moderate and severe disease stages. Glutathione reductase activity was increased, while glutathione proxidase activity was decreased in the patients with COPD, when compared to healthy controls. We found no significant difference in glutathione peroxidase and glutathione reductase activities between stages. Patients who smoked had lower concentration of total glutathione compared with former smokers and never-smoking patients. Lung function parameters were inversely associated with glutathione level. Evidence is presented for differential modulation of glutathione peroxidase and glutathione reductase activities in peripheral blood of patients with stable COPD. We suppose that in addition to glutathione biosynthesis, glutathione reductase-dependent regulation of the glutathione redox state is vital for protection against oxidative stress. Copyright © 2010 John Wiley & Sons, Ltd. [source] Fluvastatin Normalizes The Decreased Turnovers Of Glutathione And Ascorbic Acid In Watanabe Heritable Hyperlipidaemic RabbitsCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2000Kuniharu Suzumura SUMMARY 1. Fluvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, has been reported to decrease the oxidizability of plasma lipids in hyperlipidaemic subjects. In order to elucidate one of the mechanisms of this in vivo, we investigated the effects of fluvastatin and pravastatin on the decreased turnovers of reduced glutathione (GSH) and ascorbic acid (AA) in Watanabe heritable hyperlipidaemic (WHHL) rabbits. 2. These drugs (30 mg/kg per day) equally decreased plasma levels of lipids after a 4 week treatment period. However, only fluvastatin significantly decreased thiobarbituric acid-reactive substances, which were increased in the plasma of WHHL. 3. Although these drugs did not affect the steady state levels of total glutathione and low molecular weight thiols in the liver and kidney, fluvastatin markedly normalized the rate of GSH turnover in these tissues, as determined by using L -buthionine-( S, R)-sulphoximine, a specific inhibitor of GSH synthesis. 4. Fluvastatin also increased the clearance of AA from the circulation in WHHL. 5. These results suggest that, in addition to its hypolipidaemic action, fluvastatin has the potential to improve the turnover of anti-oxidants, which is closely related to the amelioration of the redox status in the body. [source] | |||||||||||||