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Antioxidant Enzyme Activities (antioxidant + enzyme_activity)
Selected AbstractsEffects of dietary N -acetylcysteine on the oxidative stress induced in tilapia (Oreochromis Niloticus) exposed to a microcystin-producing cyanobacterial water bloom,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2009María Puerto Abstract Fish can be exposed to toxic cyanobacterial cells in natural waters and fish farms and suffer from oxidative damage. The present study investigates the effects of N-acetylcysteine (NAC), a glutathione (GSH) precursor, on the oxidative stress induced by Microcystis cyanobacterial cells containing microcystins (MCs) in tilapia fish (Oreochromis niloticus). Variation in lipid peroxidation (LPO) levels, carbonyl group content, reduced glutathione to oxidized glutathione ratio (GSH: GSSG), and catalase (Enzyme Commission [EC] 1.11.1.6), superoxide dismutase (SOD; EC 1.15.1.1), glutathione reductase (GR; EC 1.8.1.7), glutathione peroxidase (GPx; EC 1.11.1.9), and glutathione S-transferase (EC 2.5.1.18) activities in liver and kidney of tilapia exposed to a single oral dose of 120 ,g MC-LR (with leucine [L] and arginine [R])/fish and killed in 24 h were investigated in the absence and presence of 20.0, 44.0, and 96.8 mg NAC/fish/d. Results showed a protective role of NAC, depending on the dose and the biomarker considered. The increase in LPO (1.9-and 1.4-fold in liver and kidney, respectively) and the decreased protein content and GSH:GSSG in the liver induced by MCs were recovered mainly by the lower doses of NAC employed. Antioxidant enzyme activities increased (range, 1.4-to 1.7-fold) by MCs also were ameliorated by NAC, although the highest level used induced significant alteration of some enzymatic activities, such as SOD, GPx, and GR. Thus, NAC can be considered to be a useful chemoprotectant that reduces hepatic and renal oxidative stress in the prophylaxis and treatment of MC-related intoxications in fish when careful attention is given to its application dose because of its own pro-oxidant activity, as shown in the present study at 96.8 mg NAC/ fish/d. [source] Effect of Salt Stress on the Salicylic Acid Synthesis in Young Maize (Zea mays L.) PlantsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2009G. Szalai Abstract The effect of salt stress on salicylic acid (SA) synthesis was investigated parallel with the induction of antioxidant enzymes in young maize plants. Two-week-old maize plants grown in hydroponic solution were treated with 50 or 100 mm NaCl for 7 days. Antioxidant enzyme activities, and the SA and o -hydroxy-cinnamic acid (oHCA) levels were measured on the 3rd and 7th day of treatment and after 4 days of recovery. Ascorbate peroxidase activity increased in the leaves, but changes in guaiacol peroxidase activity only could be detected in the roots after 7 days. Glutathione reductase activity increased both in the leaves and in the roots after the 3rd day of 100 mm NaCl treatment. Free SA only increased during recovery in the leaves and roots. In the leaves of plants treated with 100 mm NaCl, a slight increase was observed in the free oHCA level, which rose dramatically after recovery, while in the roots an increase could only be seen after recovery. These results suggest that oHCA may serve not only as a precursor of SA but may also have an antioxidant role during salt stress and recovery. [source] Antioxidant enzyme activities and DNA damage in children with type 1 diabetes mellitus after 12 weeks of exerciseACTA PAEDIATRICA, Issue 8 2010J Woo Abstract Objective:, The objectives of this study are to assess the effects of a low-intensity exercise training which is not risky for children with type 1 diabetes mellitus (T1DM) on the antioxidant enzyme activities and oxidative stresses compared with healthy controls. Patients and methods:, We studied 10 boys with T1DM (11.21 ± 0.97 age) and 10 age-matched healthy controls (11.90 ± 1.85 age) during the 12 weeks of moderate intensity aerobic exercise. Measurements included peak oxygen uptake, body composition, blood lipid profiles, glycated haemoglobin (HbA1c), oxidized low density lipoprotein (ox-LDL), 8-hydroxy-2,-deoxyguanosine, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. Results:, In T1DM patients, the baseline diastolic blood pressure and HbA1c were higher than that in controls (p < 0.05), while the GPx level was lower. The training-induced DNA damage peak was higher in T1DM patients than in controls (p < 0.05), and exercise improved both SOD and GPx levels. Conclusion:, Although our exercise programme increase antioxidant enzyme activities, the results of the study demonstrate that low-intensity aerobic exercise training programme performed over 12 weeks may accelerate adverse effects of antioxidant defence capacity in children with T1DM. Therefore, the future studies should be performed to clarify much more the relationship to exercise and antioxidant capacity in children with T1DM. [source] Effects of Eriobotrya japonica seed extract on oxidative stress in rats with non-alcoholic steatohepatitisJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2010Saburo Yoshioka Abstract Objectives Non-alcoholic steatohepatitis is associated with the deposition of lipid droplets in the liver, and is characterised histologically by the infiltration of inflammatory cells, hepatocellular degeneration and liver fibrosis. Oxidative stress may play an important role in the onset and deterioration of non-alcoholic steatohepatitis. We previously reported that an Eriobotrya japonica seed extract, extracted in 70% ethanol, exhibited antioxidant actions in vitro and in vivo. In this study, we examined the effect of this extract in a rat model of non-alcoholic steatohepatitis. Methods The seed extract was given in the drinking water to fats being fed a methionine-choline-deficient diet for 15 weeks. Key findings Increases in alanine aminotransferase and aspartate aminotransferase levels were significantly inhibited in rats fed the seed extract compared with the group on the diet alone. Formation of fatty droplets in the liver was also inhibited. Antioxidant enzyme activity in liver tissue was higher than in the diet-only group and lipid peroxidation was reduced compared with rats that also received the extract. Expression of 8-hydroxy-2,-deoxyguanosine and 4-hydroxy-2-nonenal was lower in the rats given the seed extract than in the diet-only group. In the former, liver tissue levels of transforming growth factor-, and collagen were also decreased. Conclusions Thus, the E. japonica seed extract inhibited fatty liver, inflammation and fibrosis, suggesting its usefulness in the treatment of non-alcoholic steatohepatitis. [source] Antioxidant enzyme activity and MDA level in the rat testis following chronic administration of ghrelinANDROLOGIA, Issue 6 2009A. Kheradmand Summary Ghrelin has recently been reported to exert beneficial effects on various oxidative stresses as a result of its antioxidant properties. Therefore, we designed this study to explore the probable antioxidative effects of this peptide in the testis. Twenty-eight male adult Wistar rats were divided into equal control and treatment groups. In the treatment group, 1 nmol of ghrelin was administered as subcutaneous injection for 10 consecutive days or vehicle (physiological saline) to the control rats. The control and treated rats were killed on days 6 and 10 after beginning of ghrelin injection (n = 7 from each group on each day). The testes were taken and measured for antioxidant enzyme activity and malondialdehyde (MDA) content. Glutathione peroxidase activity significantly increased on day 10 in the treated animals compared with the control group (P < 0.05). Although the mean activity of glutathione peroxidase was greater on day 6 in the ghrelin-treated group than in the control animals, it was not statistically significant. There were no significant differences in superoxide dismutase and catalase activities between the groups. However, MDA level decreased by ghrelin treatment on day 10 compared with the control rats (P < 0.05). The results of this study indicate for the first time novel evidences for antioxidant properties of ghrelin in the rat testis. [source] Antioxidant Defenses and DNA Damage Induced by UV-A and UV-B Radiation in the Crab Chasmagnathus granulata (Decapoda, Brachyura),PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005Glauce R. Gouveia ABSTRACT The photoprotector role of pigment dispersion in the melanophores of the crab, Chasmagnathus granulata, against DNA and oxidative damages caused by UV-A and UV-B was investigated. Intact and eyestalkaless crabs were used. In eyestalkless crabs, the dorsal epidermis of the cephalothorax (dispersed melanophores) and the epidermis of pereiopods (aggregated melanophores) were analyzed. Intact crabs showed only dispersed melanophores in the two epidermis. Antioxidant enzymes activity and lipoperoxidation content were analyzed after UV-A (2.5 J/cm2) or UV-B (8.6 J/sm2) irradiation. DNA damage was analyzed by single cell electrophoresis (comet) assay, after exposure to UV-B (8.6 J/cm2). UV-A radiation increased the glutatione- S -transferase activity in the pereiopods epidermis of eyestalkless crabs (P < 0.05). UV-B radiation induced DNA damage in the dorsal epidermis of eyestalkless crabs (P < 0.005). In pereiopod epidermis of eyestalkless crabs, there was no significant difference between control and UV-B-exposed crabs. In the pereiopods epidermis of eyestalkless, the control group showed higher scores of DNA damage and ,50% of cellular viability. Because in eyestalkless and irradiated crabs the cellular viability was ,5%, it was not possible to observe nuclei for determination of DNA damage. The findings show that melanophores can play a role in the defense against harmful effects of a momentary exposure to UV radiation. [source] Pharmaceutical industry effluent diluted 1:500 affects global gene expression, cytochrome P450 1A activity, and plasma phosphate in fish,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2009Lina Gunnarsson Abstract Patancheru, near Hyderabad, India, is a major production site for the global bulk drug market. Approximately 90 manufacturers send their wastewater to a common treatment plant in Patancheru. Extraordinary high levels of a wide range of pharmaceuticals have recently been demonstrated in the treated effluent. As little as 0.2% of this effluent can strongly reduce the growth rate of tadpoles, but the underlying mechanisms of toxicity are not known. To begin addressing how the effluent affects aquatic vertebrates, rainbow trout (Oncorhynchus mykiss) were exposed to 0.2% effluent for 5 d. Several physiological endpoints, together with effects on global hepatic gene expression patterns, were analyzed. The exposed fish showed both an induction of hepatic cytochrome P450 1A (CYP1A) gene expression, as well as enzyme activity. Clinical blood chemistry analyses revealed an increase in plasma phosphate levels, which in humans indicates impaired kidney function. Several oxidative stress-related genes were induced in the livers; however, no significant changes in antioxidant enzyme activities or in the hepatic glutathione levels were found. Furthermore, estrogen-regulated genes were slightly up-regulated following exposure, and moderate levels of estriol were detected in the effluent. The present study identifies changes in gene expression triggered by exposure to a high dilution of the effluent, supporting the hypothesis that these fish are responding to chemical exposure. The pattern of regulated genes may contribute to the identification of mechanisms of sublethal toxicity, as well as illuminate possible causative agents. [source] Pharmacological interventions in aging and age-associated disordersGERIATRICS & GERONTOLOGY INTERNATIONAL, Issue 2 2007Kenichi Kitani In the present study, past attempts using different pharmaceuticals and chemicals which were reported to prolong lifespans of animals are critically reviewed. Despite a large number of trials in animals and humans, the validity of supplementation of antioxidant vitamins such as vitamins A, E and C for improving human health remains unresolved at present. A recent approach using antioxidant mimetics called the EUK series which, despite an initial enthusiastically reported success in prolonging the lifespan of nematodes, remains again unsettled because of the failure in reproducing the initial success by follow-up studies. ,-Phenyl- tert -butylnitrone and related nitrones were initially introduced as radical scavengers. Some of these (e.g. disodium 2,4-disulfophenyl-N- tert -butylnitrone) are at phase 3 clinical trials as an agent to treat cerebral stroke. This effect, however, appears at least in part to be related to signal transduction which makes these agents effective against cerebral stroke even when they are administered later than its onset. (,)Deprenyl is a monoamine oxidase-B inhibitor and has some neuroprotective and anti-apoptotic effects. The drug has also been shown to prolong the lifespans of at least four different animal species. The drug upregulates superoxide dismutase and catalase activities in selective brain regions of dopaminergic nature. These effects on antioxidant enzyme activities are suspected to be causally related to its effect on lifespans of animals. Future trials using these and other drugs are expected to open new doors for interventions in aging and age-associated disorders in humans. [source] Tunisian radish extract (Raphanus sativus) enhances the antioxidant status and protects against oxidative stress induced by zearalenone in Balb/c miceJOURNAL OF APPLIED TOXICOLOGY, Issue 1 2008Jalila Ben Salah-Abbès Abstract Radish (Raphanus sativus) is a food plant known worldwide. From antiquity it has been used in folk medicine as a natural drug against many toxicants. Zearalenone (zen) is a non-steroidal estrogenic mycotoxin present in corn and food mixture for farm animals and it is hepatotoxic, hematotoxic, immunotoxic, nephrotoxic and genotoxic. The objectives of the present study were to assess the biological activity of radish extract and to evaluate the protective role of radish extract against the toxicity of zen in female Balb/c mice. Animals were divided into seven groups and treated orally for 10 days as follows: a control, an olive oil group, groups treated with radish extract alone (5, 10 and 15 mg kg,1 b.w.), a group treated with zen (40 mg kg,1 b.w.) and a group treated with zen plus the lowest dose of radish extract. The results indicate that radish extract improved the antioxidant status and had no significant effects on hematological and biochemical parameters tested or histology of the liver and kidney. Treatment with zen results in a significant increase in ALT, AST, ALP, BILT, BILD, CRE accompanied with significant changes in most of hematological parameters and the antioxidant enzyme activities, co-treatment of zen and the radish extract results in a significant reestablishment of hematological, serum biochemical parameters, and the histology of the liver and kidney. These findings suggest that radish extract is safe and can be overcome or, at least, significantly diminish zen effects. Copyright © 2007 John Wiley & Sons, Ltd. [source] Interaction of pyridostigmine and physical stress on antioxidant defense system in skeletal muscle of miceJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2001R. Jagannathan Abstract Pyridostigmine bromide (PB), a reversible anticholinesterase drug, had been used against possible nerve gas exposure during the Persian Gulf War. The Gulf War veterans used PB and they were under physical stress. This study investigated the delayed and interactive effects of pyridostigmine and physical stress on the antioxidant defense system in triceps muscle of mice. Male NIH Swiss mice were divided into four groups and treated as follows: sedentary control; pyridostigmine (1.2 mg kg,1 p.o.); exercise; and PB plus exercise. Mice were exercised for 10 weeks, but PB was administered daily during the 5th and 6th weeks. Mice were sacrificed 24 h after the last treatments and the triceps muscle was isolated and analyzed. There was a significant increase in total superoxide dismutase (CuZn-SOD + Mn-SOD) activity (141% of control) with PB plus exercise, suggesting that any influx of superoxide anions was scavenged efficiently. The Mn-SOD enzyme protein levels were reduced significantly (63% of control) by PB plus exercise. Catalase enzyme protein levels were increased significantly by exercise (132% of control) as well as by PB plus exercise (139% of control). Glutathione levels were increased significantly by exercise alone (123% of control). Pyridostigmine bromide plus exercise significantly increased the malondialdehyde concentration (124% of control) in the triceps muscle, indicating an oxidative stress response of the combination. The data indicate that a combination of PB ingestion and exercise training significantly altered the antioxidant enzyme activities, enzyme protein levels and lipid peroxidation, leading to oxidative injury. Physical stress amplified the delayed effects of PB in the skeletal muscle of mice. Copyright © 2001 John Wiley & Sons, Ltd. [source] Attenuation of TCDD-induced oxidative stress by 670 nm photobiomodulation in developmental chicken kidneyJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 4 2008Jinhwan Lim 2,3,7,8-Tetrachlorodibenzo- p -dioxin (TCDD), a potent developmental teratogen inducing oxidative stress and sublethal changes in multiple organs, provokes developmental renal injuries. In this study, we investigated TCDD-induced biochemical changes and the therapeutic efficacy of photobiomodulation (670 nm; 4 J/cm2) on oxidative stress in chicken kidneys during development. Eggs were injected once prior to incubation with TCDD (2 pg/g or 200 pg/g) or sunflower oil vehicle control. Half of the eggs in each dose group were then treated with red light once per day through embryonic day 20 (E20). Upon hatching at E21, the kidneys were collected and assayed for glutathione peroxidase, glutathione reductase, catalase, superoxide dimutase, and glutathione- S -transferase activities, as well as reduced glutathione and ATP levels, and lipid peroxidation. TCDD exposure alone suppressed the activity of the antioxidant enzymes, increased lipid peroxidation, and depleted available ATP. The biochemical indicators of oxidative and energy stress in the kidney were reversed by daily phototherapy, restoring ATP and glutathione contents and increasing antioxidant enzyme activities to control levels. Photobiomodulation also normalized the level of lipid peroxidation increased by TCDD exposure. The results of this study suggest that 670 nm photobiomodulation may be useful as a noninvasive treatment for renal injury resulting from chemically induced cellular oxidative and energy stress. © 2008 Wiley Periodicals, Inc. J Biochem Mol Toxicol 22:230,239, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20233 [source] Spatial and Temporal Ontogenies of Glutathione Peroxidase and Glutathione Disulfide Reductase During Development of the Prenatal RatJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 4 2001Hyungsuk Choe Abstract Spatial and temporal expression and regulation of the antioxidant enzymes, glutathione peroxidase (GSH-Px), glutathione disulfide reductase (GSSG-Rd) may be important in determining cell-specific susceptibility to embryotoxicants. Creation of tissue-specific ontogenies for antioxidant enzyme activities during development is an important first step in understanding regulatory relationships. Early organogenesis-stage embryos were grouped according to the somite number (GD 9,13), and fetuses were evaluated by gestational day (GD 14,21). GSH-Px activities in the visceral yolk sac (VYS) increased on consecutive days from GD 9 to GD 13, representing a 5.7-fold increase during this period of development. GSH-Px activities in VYS decreased after GD 13, ultimately constituting a 37% decrease at GD 21. Head, heart, and trunk specific activities generally increased from GD 9 to GD 13 albeit not to the same magnitude as detected in the VYS. GSSG-Rd activities showed substantial increases in the VYS from GD 9 to GD 13, 6.3-fold and decreased thereafter to 50% by GD 21. The greatest changes in enzyme activities were noted in the period between GD 10 and GD 11, where the embryo establishes an active cardiovascular system and begins to convert to aerobic metabolism. Generally, from GD 14,21, embryonic organ GSH-Px and GSSG-Rd activities either remained constant or increased as gestation progressed. These studies suggest the importance of the VYS in dealing with ROS and protecting the embryo. Furthermore, understanding the consequences of lower antioxidant activities during organogenesis may help to pinpoint periods of teratogenic susceptibility to xenobiotics and increased oxygen. © 2001 John Wiley & Sons, Inc. J Biochem Mol Toxicol 15:197,206, 2001 [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] EFFECT OF BUTYRIC ACID SUPPLEMENTATION ON SERUM AND RENAL ANTIOXIDANT ENZYME ACTIVITIES IN STREPTOZOTOCIN-INDUCED DIABETIC RATSJOURNAL OF FOOD BIOCHEMISTRY, Issue 2010A. PUNEETH KUMAR ABSTRACT Reactive oxygen metabolites, which are constant products of normal aerobic cell metabolism, play a key role in worsening the pathophysiological complications of diabetes. The present investigation was aimed at understanding the effect of butyric acid supplementation along with wheatbran and guar gum on serum and renal antioxidant enzyme activities and lipid peroxidation in streptozotocin (STZ)-induced diabetic rats. Activities of superoxide dismutase, catalase, glutathione peroxidase were evaluated in serum and kidney of control and experimental rats. Results clearly showed that the altered activity of the enzymes during diabetes was significantly ameliorated by butyric acid (500 mg/kg body weight/day) supplementation compared with other experimental groups. Further, the increased lipid peroxidation in serum and kidney of diabetic rats was also significantly reduced in butyric acid-supplemented diabetic rats. The study led us to conclude that butyric acid exert antioxidant property, thereby minimizing oxidative stress induced diabetes and its related complications. PRACTICAL APPLICATIONS Butyric acid , a product of dietary fiber fermentation , is a four-carbon fatty acid, which has wide range of application in disease management. This product is involved in various physiological functions of body like cell differentiation, apoptosis, colonic homeostasis, histone acetylation, etc. It is also known to decrease the incidence of bowel cancer and some of its analogues are shown to selectively improve glucose-stimulated insulin release and glucose tolerance in both normal and diabetic rats. This study aims to evaluate the beneficial effects of butyric acid supplementation on oxidative stress-induced diabetic complications in rats. [source] Melatonin increases activities of glutathione peroxidase and superoxide dismutase in fetal rat brainJOURNAL OF PINEAL RESEARCH, Issue 2 2000Yuji Okatani Melatonin is a powerful scavenger of oxygen free radicals. In humans, melatonin is rapidly transferred from the maternal to the fetal circulation. To investigate whether or not maternal melatonin administration can protect the fetal rat brain from radical-induced damage by increasing the activities of antioxidant enzymes, we administered melatonin to pregnant rats on day 20 of gestation. Melatonin (10 mg/kg) was injected intraperitoneally at daytime (14:00 hr) and, to remove the fetuses, a laparotomy was performed at 1, 2, or 3 hr after its administration. We measured the melatonin concentration in the maternal serum and in fetal brain homogenates and determined the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in fetal brain homogenates. Melatonin administration markedly increased melatonin concentrations in the maternal serum and fetal brain homogenates, with peak levels achieved 1 hr after melatonin administration (serum: 538.2±160.7 pM/mL; brain homogenates: 13.8±2.8 pM/mg protein). Between 1 and 3 hr after melatonin administration, GSH-Px activity in fetal brain homogenates increased significantly (P<0.01). Similarly, SOD activity increased significantly between 1 and 2 hr after melatonin administration (P<0.01). These results indicate that melatonin administration to the mother increases antioxidant enzyme activities in the fetal brain and may thereby provide indirect protection against free radical injury. Thus, melatonin may potentially be useful in the treatment of neurodegenerative conditions that may involve excessive free radical production, such as fetal hypoxia and preeclampsia. [source] The protective effects of garlic oil on acute ethanol-induced oxidative stress in the liver of miceJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2008Tao Zeng Abstract BACKGROUND: Alcoholic liver disease is so serious that no effective therapies have been developed up to now. This study was conducted to elucidate the effects of garlic oil (GO) on acute ethanol-induced liver injury. Male Kun-Ming mice were orally administered GO (50, 100 or 200 mg kg,1) for 30 days and then ethanol (4.8 g kg,1). At 16 h after ethanol treatment the mice were sacrificed. Subsequent serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and triglyceride (TG) levels, hepatic malondialdehyde (MDA) and glutathione (GSH) levels and antioxidant enzyme activities were measured. Histopathological examination of mouse liver sections was performed by Sudan III staining. RESULTS: GO pretreatment significantly inhibited acute ethanol-induced increase in ALT, AST, TG and MDA and decrease in GSH in a dose-dependent manner. In the three GO groups the level of GSH increased by 10.3%, 15.8% (P < 0.05) and 25.5% (P < 0.01) respectively compared with that in the ethanol group. The activities of superoxide dismutase, catalase and glutathione reductase were increased markedly in the 200 mg kg,1 GO group (P < 0.01). Histopathological examination showed fewer fat droplets in liver sections of GO-pretreated mice. CONCLUSION: GO may have protective effects against acute ethanol-induced liver injury through restoration of the GSH level and enhancement of the activities of antioxidant enzymes. Copyright © 2008 Society of Chemical Industry [source] Influence of enrofloxacin administration on the proteolytic and antioxidant enzyme activities of raw and cooked turkey productsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2005Irene Carreras Abstract The objective of this study was to assess the effect of enrofloxacin administration with and without withdrawal period on the quality of fresh meat and cooked products from turkey breasts. Cathepsin B and L activities were inactivated by the thermal process but were not affected by the presence of enrofloxacin. The level of enrofloxacin in samples without withdrawal time was higher than the regulatory maximum residue limit (MRL). The antioxidant enzymes glutathione peroxidase (GSHPx) and catalase (CAT) were affected by both the thermal process and the antibiotic residues in cooked meat. In no cases were differences found in superoxide dismutase (SOD) activity, supporting the theory that this enzyme could play a major role in preventing lipid oxidation of cooked meat. Enrofloxacin residues could contribute to an increase in the oxidative stress produced by thermal processing, as can be deduced by the reduction in GSHPx and CAT activities. Copyright © 2005 Society of Chemical Industry [source] Time-course of lipoxygenase, antioxidant enzyme activities and H2O2 accumulation during the early stages of Rhizobium,legume symbiosisNEW PHYTOLOGIST, Issue 1 2001Pablo Bueno Summary ,,The involvement of lipoxygenase and antioxidant enzyme activities as well as hydrogen peroxide (H2O2) accumulation are reported during early infection steps in alfalfa (Medicago sativa) roots inoculated either with a wild type Sinorhizobium meliloti or with a mutant defective in Nod-factor synthesis (Nod C,). ,,Compatibility between M. sativa and Rhizobium correlates, at least in part, with an increase in the activities of these enzymes, particularly catalase and lipoxygenase, during the preinfection period (up to 12 h). The mutant strain, defective in Nod-factor biosynthesis, showed a decrease in all enzyme activities assayed, and an increase in H2O2 accumulation. ,,Enhancement of scavenging activities for several reactive oxygen species correlated with compatibility of the S. meliloti,alfalfa symbiosis, whereas the Nod C, strain triggered a defence response. Nod factors were essential to suppress this response. ,,Increase in lipoxygenase and lipid hydroperoxide decomposing activities, observed during the first hours after inoculation with a compatible strain, could be related to tissue differentiation and/or the production of signal molecules involved in autoregulation of nodulation by the plant. [source] Effects of L-arginine and L-carnitine in hypoxia/reoxygenation-induced intestinal injuryPEDIATRICS INTERNATIONAL, Issue 1 2005Ceyda Kabaroglu Abstract,Background:,This study was designed to show the role of oxidative stress, nitric oxide and glutathione-related antioxidant enzymes in hypoxia/reoxygenation (H/R)-induced intestinal injury model in mice and to evaluate the potential benefits of arginine and carnitine supplementation. Methods:,A total of 28 young Balb/c mice were divided into four groups: Group 1 (untreated) was given physiological saline before the experiment; group 2 H/R mice were supplemented with L-arginine; group 3 H/R mice were given L-carnitine for 7 days; and group 4 mice served as controls. At the end of day 7, H/R injury was induced and intestinal tissue malondialdehyde (MDA), nitrate levels and glutathione peroxidase (GSH-Px), glutathione reductase (GR) and glutathione-S-transferase (GST) activities were measured. Results:,MDA levels were higher in the untreated animals than in the other three groups. MDA levels were higher in the L-arginine-treated animals than in the L-carnitine-treated animals. Nitrate levels were found to be increased in the L-arginine-treated group when compared to the controls. GSH-Px and GR activities were increased in the untreated, the L-arginine and the L-carnitine-treated H/R groups when compared to the control group. GST activities were indifferent between the groups. Conclusions:,Oxidative stress contributes to the pathogenesis of H/R-induced intestinal injury. The glutathione redox cycle may have a crucial role in the H/R-induced intestinal injury. L-arginine and L-carnitine supplementations ameliorate the histological evidence of H/R-induced intestinal injury and decrease lipid peroxidation but do not alter the glutathione-related antioxidant enzyme activities. [source] Antioxidant effect of squeezed juice from black radish (Raphanus sativus L. var niger) in alimentary hyperlipidaemia in ratsPHYTOTHERAPY RESEARCH, Issue 7 2005Andrea Lugasi Abstract Black radish (Raphanus sativus L. var. niger) root has been used in folk medicine since antiquity as a natural drug for the stimulation of bile function. According to in vitro studies the squeezed juice from black radish root exhibited significant antioxidant properties. In the present study, the beneficial effect of the black radish juice on some free radical reactions in rats fed with a diet rich in lipids (20% sunflower oil, 2% cholesterol, 0.5% cholic acid in normal chow) was examined. Thiobarbituric acid reactive substances and conjugated diene concentrations were significantly higher, while the antioxidant enzyme activities and the free radical scavenging capacity were lower in hyperlipidaemic rats compared with normal controls. Supplementation of the lipid-rich diet with black radish juice resulted in a significant improvement of the parameters mentioned above. Although the exact mechanism of the biologically active compounds in black radish on the lipid metabolism and lipid peroxidation is not clear yet, a beneficial effect of the drug was evident in alimentary hyperlipidaemia. Copyright © 2005 John Wiley & Sons, Ltd. [source] Panax notoginseng saponins attenuate acute lung injury induced by intestinal ischaemia/reperfusion in ratsRESPIROLOGY, Issue 6 2009Ling RONG ABSTRACT Background and objective: Acute lung injury remains a challenge for both clinicians and scientists. The effects of Panax notoginseng saponins (PNS) on acute lung injury induced by intestinal ischaemia/reperfusion (II/R) were studied in rats. Methods: Forty-eight Wistar rats were randomly assigned to four groups: (1) a sham-operated group that received laparotomy without II/R (n= 12); (2) a sham + PNS group, which was identical to group 1 except for PNS treatment (n= 12); (3) an II/R group that had 1 h of intestinal ischaemia followed by 3 h of reperfusion (n= 12); and (4) an II/R + PNS group that received 100 mg/kg of PNS, i.v., 15 min before reperfusion (n= 12). The effects of PNS administration on lung tissue histology, activities of oxidant and antioxidant enzymes, levels of malondialdehyde, nitric oxide and inducible nitric oxide synthase activity were examined. Levels of surfactant protein B, cell numbers in BAL fluid and plasma levels of pro-inflammatory cytokines were also examined. Results: Compared with the II/R group, pulmonary parenchymal damage, activities of oxidant enzymes, levels of malondialdehyde and nitric oxide, inducible nitric oxide synthase activity in lung tissue, and plasma levels of pro-inflammatory cytokines were significantly reduced by PNS treatment. In addition, the decreases in antioxidant enzyme activities were prevented in the II/R + PNS group. Total leukocyte and neutrophil counts were significantly decreased by PNS treatment. The decline in surfactant protein B levels in BAL fluid was reduced in the II/R + PNS group compared with the II/R group. Conclusions: Administration of PNS before reperfusion injury alleviates acute lung injury induced by II/R, and this is attributable to the antioxidant and anti-inflammatory effects of PNS. [source] Effect of supplemental l -ascorbyl-2-polyphosphate in enriched live food on the antioxidant defense system of Penaeus vannamei of different sizes exposed to ammonia-NAQUACULTURE NUTRITION, Issue 5 2006W.-N. WANG Abstract The effects of supplemental l -ascorbyl-2-polyphosphate (APP) in enriched live food (Artemia) on reactive oxygen intermediate (ROI) and free radical scavenging enzyme (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione transferase) activities in the muscle of Penaeus vannamei of two sizes exposed to ambient ammonia-N, were investigated. Significantly, decreased ROI value was found in prawns fed on enriched Artemia compared with those fed on starved Artemia (P < 0.05); the decrease was 24% and 36%, respectively. In both size classes, the antioxidant enzyme activities in prawns fed on enriched Artemia were higher than in those fed on starved Artemia (P < 0.05). The results demonstrated that the supplementation of ascorbic acid in enriched live food (Artemia) enhanced the antioxidant capacity of prawn, increasing its defense system that may fight against environmental stress, leading to impaired ammonia toxicity. [source] Myo -inositol prevents oxidative damage, inhibits oxygen radical generation and increases antioxidant enzyme activities of juvenile Jian carp (Cyprinus carpio var. Jian)AQUACULTURE RESEARCH, Issue 15 2009Wei-Dan Jiang Abstract This study was conducted to evaluate the effects of dietary myo -inositol (MI) on the antioxidant status of juvenile Jian carp (Cyprinus carpio var. Jian). A total of 1050 Jian carp (22.28±0.07 g) were randomly distributed into seven groups of three replicates each, feeding diets containing graded levels of MI (163.5, 232.7, 384.2, 535.8, 687.3, 838.8 and 990.3 mg kg,1 diet) for 60 days. Results indicated that the malondialdehyde content was the lowest for fish fed diets containing ,384.2 mg MI kg,1, and the highest for fish fed the MI-unsupplemented basal diet (P<0.05). The protein carbonyl content was decreased with increasing dietary MI levels up to 535.8 mg kg,1 diet, and no differences were found with a further increase in the MI concentration. The anti-superoxide anion capacity (ASA) and anti-hydroxyl radical capacity (AHR) were increased with increasing MI levels up to 535.8 mg kg,1 diet, and plateaued thereafter. The superoxide dismutase and glutathione- S -transferase activities showed the same tendency with the ASA capacity. Catalase, glutathione peroxidase and glutathione reducase activities were improved with increasing MI levels up to 838.8, 384.2 and 687.3 mg kg,1 diet, respectively, and remained nearly constant thereafter. These results suggested that MI could inhibit oxygen radical generation, increase enzymatic antioxidant capacity and prevent oxidative damage of carp. Dietary MI requirements for ASA and AHR activities of juvenile Jian carp were 567.94 and 517.22 mg MI kg,1 diet respectively. [source] Therapeutic effect of phytoecdysteroids rich extract from Ajuga iva on alloxan induced diabetic rats liver, kidney and pancreasBIOFACTORS, Issue 3 2008Khaled Hamden Abstract In the current study, the effect of Ajuga iva extract on blood glucose, lipid profile, hepatic and renal toxicity and antioxidant enzyme activities in alloxan-induced diabetic rats was investigated. Diabetes was confirmed by measuring the glucoserua concentration 15 days after alloxan administration. Ajuga iva extract was administrated orally 3 weeks after alloxan injection. Our results investigate that Ajuga iva extract supplementation increased the levels of both enzymatic antioxidant (superoxide dismutase, catalase and gluthation peroxidase) and metals antioxidants (iron, copper, magnesium, calcuim) and decreased lipid peroxidation level (TBARs). Besides Ajuga iva ameliorated diabetes provoked hepatic and renal toxicity appeared by a lower level in total and direct bilirubin, urea, creatinine, triglyceride (TG), cholesterol and a higher level in HDL-cholesterol. Besides, the activities of phosphatase alkalines (PAL), aspartate and lactate transaminase (AST & ALT) were decreased. The benefices effects of phytoecdysteroids of Ajuga iva confirmed by histological observation in pancreatic tissues. In conclusion, Ajuga iva phytoecdysteroids supplements seem to be beneficial for correcting the hyperglycemia and preventing diabetic complications in liver, pancreas and kidneys. [source] Piracetam improves mitochondrial dysfunction following oxidative stressBRITISH JOURNAL OF PHARMACOLOGY, Issue 2 2006Uta Keil Mitochondrial dysfunction including decrease of mitochondrial membrane potential and reduced ATP production represents a common final pathway of many conditions associated with oxidative stress, for example, hypoxia, hypoglycemia, and aging. Since the cognition-improving effects of the standard nootropic piracetam are usually more pronounced under such pathological conditions and young healthy animals usually benefit little by piracetam, the effect of piracetam on mitochondrial dysfunction following oxidative stress was investigated using PC12 cells and dissociated brain cells of animals treated with piracetam. Piracetam treatment at concentrations between 100 and 1000 ,M improved mitochondrial membrane potential and ATP production of PC12 cells following oxidative stress induced by sodium nitroprusside (SNP) and serum deprivation. Under conditions of mild serum deprivation, piracetam (500 ,M) induced a nearly complete recovery of mitochondrial membrane potential and ATP levels. Piracetam also reduced caspase 9 activity after SNP treatment. Piracetam treatment (100,500 mg kg,1 daily) of mice was also associated with improved mitochondrial function in dissociated brain cells. Significant improvement was mainly seen in aged animals and only less in young animals. Moreover, the same treatment reduced antioxidant enzyme activities (superoxide dismutase, glutathione peroxidase, and glutathione reductase) in aged mouse brain only, which are elevated as an adaptive response to the increased oxidative stress with aging. In conclusion, therapeutically relevant in vitro and in vivo concentrations of piracetam are able to improve mitochondrial dysfunction associated with oxidative stress and/or aging. Mitochondrial stabilization and protection might be an important mechanism to explain many of piracetam's beneficial effects in elderly patients. British Journal of Pharmacology (2006) 147, 199,208. doi:10.1038/sj.bjp.0706459 [source] Effects of , -carotene on antioxidant status in rats with chronic alcohol consumptionCELL BIOCHEMISTRY AND FUNCTION, Issue 6 2009Wan-Teng Lin Abstract This study examined the effects of , -carotene on antioxidant status in rats with chronic alcohol consumption. At the beginning of experiment (week 0), according to both the plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities, rats (n,=,24) were divided into 3 groups and fed with a standard diet (group C), a diet containing ethanol (group E), or a diet containing ethanol and , -carotene (group E+B). After 10 weeks, plasma AST and ALT, fat accumulation in the liver, antioxidant enzyme activities in erythrocytes and the liver, malondialdehyde (MDA), and , -tocopherol and retinol in plasma and hepatic samples were analyzed. The chronic alcohol diet significantly increased AST and ALT levels in plasma, and these changes were prevented by supplementing the diet with , -carotene. Glutathione (GSH) in erythrocytes and in the liver was significantly elevated in rats fed with a diet containing , -carotene. The results indicate that , -carotene supplementation can prevent ethanol-induced liver damage and increase GSH concentrations in erythrocytes and the liver. Copyright © 2009 John Wiley & Sons, Ltd. [source] MRP1/GS-X pump ATPase expression: is this the explanation for the cytoprotection of the heart against oxidative stress-induced redox imbalance in comparison to skeletal muscle cells?CELL BIOCHEMISTRY AND FUNCTION, Issue 1 2007Maurício S. Krause Abstract Striated muscle activity is always accompanied by oxidative stress (OxStress): the more intense muscle work and/or its duration, the more a redox imbalance may be attained. In spite of cardiac muscle functioning continuously, it is well known that the heart does not suffer from OxStress-induced damage over a broad physiological range. Although the expression of antioxidant enzymes may be of importance in defending heart muscle against OxStress, a series of combined antioxidant therapeutic approaches have proved to be mostly ineffective in avoiding cellular injury. Hence, additional mechanisms may be involved in heart cytoprotection other than antioxidant enzyme activities. The strong cardiotoxic effect of doxorubicin-induced cancer chemotherapy shed light on the possible role for multidrug resistance-associated proteins (MRP) in this context. Muscle activity-induced ,physiological' OxStress enhances the production of glutathione disulfide (GSSG) thus increasing the ratio of GSSG to glutathione (GSH) content inside the cells, which, in turn, leads to redox imbalance. Since MRP1 gene product (a GS-X pump ATPase) is a physiological GSSG transporter, adult Wistar rats were tested for MRP1 expression and activity in the heart and skeletal muscle (gastrocnemius), in as much as the latter is known to be extremely sensitive to muscle activity-induced OxS. MRP1 expression was completely absent in skeletal muscle. In contrast, the heart showed an exercise training-dependent induction of MRP1 protein expression which was further augmented (2.4-fold) as trained rats were challenged with a session of acute exercise. On the other hand, inducible expression of the 70-kDa heat shock protein (HSP70), a universal marker of cellular stress, was completely absent in the heart of sedentary and acutely exercised rats, whereas skeletal muscle showed a conspicuous exercise-dependent HSP70 expression, which decreased by 45% with exercise training. This effect was paralleled by a 58% decrease in GSH content in skeletal muscle which was even higher (an 80%-fall) after training thus leading to a marked redox imbalance ([GSSG]/[GSH] raised up to 38-fold). In the heart, GSH contents and [GSSG]/[GSH] ratio remained virtually unchanged even after exercise challenges, while GS-X pump activity was found to be 20% higher in the heart related to skeletal muscle. These findings suggest that an intrinsic higher capacity to express the MRP1/GS-X pump may dictate the redox status in the heart muscle thus protecting myocardium by preventing GSSG accumulation in cardiomyocytes as compared to skeletal muscle fibres. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effect of selenium on N-nitrosodiethylamine-induced multistage hepatocarcinogenesis with reference to lipid peroxidation and enzymic antioxidantsCELL BIOCHEMISTRY AND FUNCTION, Issue 1 2001C. Thirunavukkarasu Abstract We have studied the relationship between antioxidant and anticancer properties of selenium (Se) in multistage hepatocarcinogenesis induced by N-nitrosodiethylamine (DEN). In this study we have observed an increased level of lipid peroxide (LPO) products and decreased antioxidant enzyme activities (superoxide dismutase and catalase) in hepatoma and surrounding liver tissues of cancer-bearing animals. Selenium (Se) was supplemented either before initiation or during initiation and selection/promotion phases of hepatocarcinogenesis and was found to be effective in altering hepatic lipid peroxidation and antioxidant enzyme activities to a statistically significant level measured either in the hepatoma or in the surrounding liver tissues. These alterations inclined towards normal in a time-dependent manner on selenium supplementation. Furthermore, increased levels of lipid peroxidation and decreased levels of antioxidants (superoxide dismutase and catalase) were also observed in distant organs of cancer-bearing rats other than the tumour-bearing site. These alterations are brought back to normal levels upon Se treatment. Our results confirm the fact that Se is particularly protective in limiting the action of DEN by its antioxidant property. Copyright © 2001 John Wiley & Sons, Ltd. [source] Antioxidant enzyme activities and DNA damage in children with type 1 diabetes mellitus after 12 weeks of exerciseACTA PAEDIATRICA, Issue 8 2010J Woo Abstract Objective:, The objectives of this study are to assess the effects of a low-intensity exercise training which is not risky for children with type 1 diabetes mellitus (T1DM) on the antioxidant enzyme activities and oxidative stresses compared with healthy controls. Patients and methods:, We studied 10 boys with T1DM (11.21 ± 0.97 age) and 10 age-matched healthy controls (11.90 ± 1.85 age) during the 12 weeks of moderate intensity aerobic exercise. Measurements included peak oxygen uptake, body composition, blood lipid profiles, glycated haemoglobin (HbA1c), oxidized low density lipoprotein (ox-LDL), 8-hydroxy-2,-deoxyguanosine, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. Results:, In T1DM patients, the baseline diastolic blood pressure and HbA1c were higher than that in controls (p < 0.05), while the GPx level was lower. The training-induced DNA damage peak was higher in T1DM patients than in controls (p < 0.05), and exercise improved both SOD and GPx levels. Conclusion:, Although our exercise programme increase antioxidant enzyme activities, the results of the study demonstrate that low-intensity aerobic exercise training programme performed over 12 weeks may accelerate adverse effects of antioxidant defence capacity in children with T1DM. Therefore, the future studies should be performed to clarify much more the relationship to exercise and antioxidant capacity in children with T1DM. [source] Malathion-induced oxidative stress in human erythrocytes and the protective effect of vitamins C and E in vitroENVIRONMENTAL TOXICOLOGY, Issue 3 2009Dilek Durak Abstract Malathion is an organophosphate (OP) pesticide that has been shown to induce oxidative stress in erythrocytes through the generation of free radicals and alteration of the cellular antioxidant defense system. We examined the effect of several different doses of malathion (25, 75, 200 ,M), or malathion in combination with vitamin C (VC; 10 ,M) or vitamin E (VE; 30 ,M), on the levels of malondialdehyde (MDA), and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities in human erythrocytes in vitro. Erythrocytes were incubated under various treatment conditions (malathion alone, vitamins alone, or malathion plus vitamin) at 37°C for 60 min, and the levels of MDA, and SOD, CAT and GPx activities, were determined. Treatment with malathion alone increased the levels of MDA and decreased SOD, CAT, and GPx activities in erythrocytes (P < 0.05). There were no statistical differences among VC-treated, VE-treated, or VC + VE-treated erythrocyes, as compared with nontreated control cells. Treatment of cells with malathion + VC, malathion + VE, or a combination of all three agents prevented malathion-induced changes in antioxidant enzyme activity and lipid peroxidation. However, this effect was seen only at low concentrations of malathion (25 and 75 ,M), and the combination of VC + VE had a more protective effect than VC or VE alone. These results indicated that the presence of vitamins at concentrations that are similar to the levels found in plasma have no effect on malathion-induced toxicity in erythrocytes at a concentration of malathion (200 ,M) that is typically used in pesticides. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009. [source] | |||||||||||||||||||||||||||||||