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Antioxidative Effects (antioxidative + effects)
Selected AbstractsAntioxidative effects of pumpkin seed (Cucurbita pepo) protein isolate in CCl4-Induced liver injury in low-protein fed ratsPHYTOTHERAPY RESEARCH, Issue 11 2006C. Z. Nkosi Abstract The effects of pumpkin seed (Cucurbita pepo) protein isolate on the plasma activity levels of catalase (CA), superoxide dismutase (SOD), glutathione peroxidase (GSHpx) and total antioxidant capacity (TAC) as well as glucose-6-phosphatase (G6Pase) in liver homogenates and lipid peroxidation (LPO-malondialdehyde-MDA) levels in liver homogenates and liver microsomal fractions against carbon tetrachloride (CCl4)-induced acute liver injury in low-protein fed Sprague-Dawley rats (Rattus norvegicus) were investigated. A group of male Sprague-Dawley rats maintained on a low-protein diet for 5 days were divided into three subgroups. Two subgroups were injected with carbon tetrachloride and the other group with an equivalent amount of olive oil. Two hours after CCl4 intoxication one of the two subgroups was administered with pumpkin seed protein isolate and thereafter switched onto a 20% pumpkin seed protein isolate diet. The other two groups of rats were maintained on the low-protein diet for the duration of the investigation. Groups of rats from the different subgroups were killed at 24, 48 and 72 h after their respective treatments. After 5 days on the low-protein diet the activity levels of all the enzymes as well as antioxidant levels were significantly lower than their counterparts on a normal balanced diet. However, a low-protein diet resulted in significantly increased levels of lipid peroxidation. The CCl4 intoxicated rats responded in a similar way, regarding all the variables investigated, to their counterparts on a low-protein diet. The administration of pumpkin seed protein isolate after CCl4 intoxication resulted in significantly increased levels of all the variables investigated, with the exception of the lipid peroxidation levels which were significantly decreased. From the results of the present study it is concluded that pumpkin seed protein isolate administration was effective in alleviating the detrimental effects associated with protein malnutrition and CCl4 intoxication. It is therefore apparent that pumpkin seed protein isolate has components that have antiperoxidative properties. Copyright © 2006 John Wiley & Sons, Ltd. [source] Antioxidative effects of 7-hydroxy-3-methoxy-cadalene extracted from Zelkova serrata on 4-(methylinitros amino)-1-(3-pyridyl)-1-butanone-induced oxidative stress in A/J micePHYTOTHERAPY RESEARCH, Issue 5 2004J. H. Kim Abstract Effects of 7-hydroxy-3-methoxy-cadalene (cadalene) extracted from Zelkova serrata on 4-(methylinitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced oxidative stress were examined using A/J mice. NNK (65 µg/ml water) was orally administered to 20 mice for 7 weeks, followed by free feeding of a commercial diet, not containing cadalene, for 2 weeks. The control group was maintained without NNK and cadalene administration, and treatment groups with NNK and cadalene (6.25, 25, 100 mg/kg feed) feeding for 25 weeks. The glutathione concentration of cadalene-treated (65 µg/ml water) group was signi,cantly higher than that of the group treated only with NNK (p < 0.05). The results of our study strongly indicate that cadalene exerts antioxidative effect on NNK-induced lung tumorigenesis in A/J mice. Copyright © 2004 John Wiley & Sons, Ltd. [source] Haem oxygenase-1 genotype and cardiovascular adverse events in patients with peripheral artery diseaseEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2005P. Dick Abstract Background, A functional GT dinucleotide length polymorphism in the haem oxygenase-1 (HO-1) gene promoter is thought to be involved in the pathogenesis of cardiovascular disease. Short (< 25) (GT)n repeats are suggested to facilitate enhanced HO-1 up-regulation in response to injury and confer potent anti-inflammatory and antioxidative effects. Materials and methods, We investigated the association between the HO-1 GT-polymorphism and cardiovascular outcome in 472 patients with advanced peripheral artery disease. Cardiovascular risk profile and DNA samples for determination of the HO-1 genotype (carrier vs. noncarrier of a short (GT)n repeat allele) were obtained at baseline, and patients were followed for median 21 months for the occurrence of coronary events (myocardial infarction, percutaneous coronary interventions and coronary artery bypass graft), cerebrovascular events (stroke or carotid revascularization) and all-cause mortality. Results, Coronary events occurred in 48 patients (9%), cerebrovascular events in 40 patients (9%) and 59 patients (13%) died. In total, 173 major adverse cardiovascular events (MACE) occurred in 133 patients (28%). Carriers of the short (GT)n repeat allele had a 0·46-fold reduced adjusted hazard ratio for coronary events (P = 0·016) as compared to noncarriers. No significant difference was found for cerebrovascular events, mortality and overall MACE. Conclusion, Apparently, the HO-1 genotype exerts potentially protective effects against coronary adverse events in patients with peripheral artery disease. Homozygous and heterozygous carriers of < 25 (GT)n repeats had lower rates of myocardial infarction, percutaneous coronary interventions and coronary bypass operations compared to patients with longer (GT)n repeats. [source] Induction of cellular resistance against Kupffer cell,derived oxidant stress: A novel concept of hepatoprotection by ischemic preconditioningHEPATOLOGY, Issue 2 2003Rolf J. Schauer Ischemic preconditioning (IP) triggers protection of the liver from prolonged subsequent ischemia. However, the underlying protective mechanisms are largely unknown. We investigated whether and how IP protects the liver against reperfusion injury caused by Kupffer cell (KC)-derived oxidants. IP before 90 minutes of warm ischemia of rat livers in vivo significantly reduced serum alanine aminotransferase (AST) levels and leukocyte adherence to sinusoids and postsinusoidal venules during reperfusion. This protective effect was mimicked by postischemic intravenous infusion of glutathione (GSH), an antioxidative strategy against KC-derived H2O2. Interestingly, no additional protection was achieved by infusion of GSH to preconditioned animals. These findings and several additional experiments strongly suggest IP mediated antioxidative effects: IP prevented oxidant cell injury in isolated perfused rat livers after selective KC activation by zymosan. Moreover, IP prevented cell injury and pertubations of the intracellular GSH/GSSG redox system caused by direct infusion of H2O2 (0.5 mmol/L). IP-mediated resistance against H2O2 could neither be blocked by the adenosine A2a antagonist DMPX nor mimicked by A2a agonist CGS21680. In contrast, H2O2 resistance was abolished by the p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB203580, but induced when p38 MAPK was directly activated by anisomycin. In conclusion, we propose a novel concept of hepatoprotection by IP: protection of liver cells by enhancing their resistance against KC-derived H2O2. Activation of p38 MAPK and preservation of the intracellular GSH/oxidized glutathione (GSSG) redox system, but not adenosine A2a receptor stimulation, seems to be pivotal for the development of H2O2 resistance in preconditioned livers. [source] The influence of curcumin and manganese complex of curcumin on cadmium-induced oxidative damage and trace elements status in tissues of miceJOURNAL OF APPLIED TOXICOLOGY, Issue 3 2006Vladislav Eybl Abstract Curcumin (diferuoyl methane) from turmeric is a well-known biologically active compound. It has been shown to ameliorate oxidative stress and it is considered to be a potent cancer chemopreventive agent. In our previous study the antioxidative effects of curcumin in cadmium exposed animals were demonstrated. Also manganese exerts protective effects in experimental cadmium intoxication. The present study examined the ability of the manganese complex of curcumin (Mn-curcumin) and curcumin to protect against oxidative damage and changes in trace element status in cadmium-intoxicated male mice. Curcumin or Mn-curcumin were administered at equimolar doses (0.14 mmol/kg b.w.) for 3 days, by gastric gavages, dispersed in methylcellulose. One hour after the last dose of antioxidants, cadmium chloride (33 µmol/kg) was administered subcutaneously. Both curcumin and Mn-curcumin prevented the increase of hepatic lipid peroxidation , expressed as MDA level, induced by cadmium intoxication and attenuated the Cd-induced decrease of hepatic GSH level. No change in hepatic glutathione peroxidase or catalase activities was found in Cd-exposed mice. A decreased GSH-Px activity was measured in curcumin and Mn-curcumin alone treated mice. Neither curcumin nor Mn-curcumin treatment influenced cadmium distribution in the tissues and did not correct the changes in the balance of essential elements caused by Cd-treatment. The treatment with Mn-curcumin increased the Fe and Mn content in the kidneys of both control and Cd-treated mice and Fe and Cu content in the brain of control mice. In conclusion, regarding the antioxidative action, introducing manganese into the curcumin molecule does not potentiate the studied effects of curcumin. Copyright © 2005 John Wiley & Sons, Ltd. [source] Comparison of potential protective effects of melatonin, indole-3-propionic acid, and propylthiouracil against lipid peroxidation caused by potassium bromate in the thyroid glandJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2005Malgorzata Karbownik Abstract Potassium bromate (KBrO3) is a prooxidant and carcinogen, inducing thyroid tumors. Melatonin and indole-3-propionic acid (IPA) are effective antioxidants. Some antioxidative effects of propylothiouracil (PTU),a thyrostatic drug,have been found. The aim of the study was to compare protective effects of melatonin, IPA, and PTU against lipid peroxidation in the thyroids, collected from rats treated with KBrO3, and in homogenates of porcine thyroids, incubated in the presence of KBrO3. Wistar rats were administered KBrO3 (110 mg/kg b.w., i.p., on the 10th day of the experiment) and/or melatonin, or IPA (0.0645 mmol/kg b.w., i.p., twice daily, for 10 days), or PTU (0.025% solution in drinking water, for 10 days). Homogenates of porcine thyroids were incubated for 30 min in the presence of KBrO3 (5 mM) plus one of the antioxidants: melatonin (0.01, 0.1, 0.5, 1.0, 5.0, 7.5 mM), or IPA (0.01, 0.1, 0.5, 1.0, 5.0, 7.5, 10.0 mM), or PTU (0.01, 0.1, 0.5, 1.0, 5.0, 7.5, 10.0 mM). The level of lipid peroxidation products (MDA,+,4-HDA) was measured spectrophotometrically in thyroid homogenates. In vivo pretreatment with either melatonin or with IPA or with PTU decreased lipid peroxidation caused by KBrO3,injections in rat thyroid gland. Under in vitro conditions, PTU (5.0, 7.5, and 10.0 mM), but neither melatonin nor IPA, reduced KBrO3 -related lipid peroxidation in the homogenates of porcine thyroids. In conclusion, melatonin and IPA may be of great value as protective agents under conditions of exposure to KBrO3. © 2005 Wiley-Liss, Inc. [source] Antioxidative capacity produced by Bifidobacterium - and Lactobacillus acidophilus -mediated fermentations of konjac glucomannan and glucomannan oligosaccharidesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2008Cheng-Hsin Wang Abstract BACKGROUND: Konjac glucomannan (KGM) has been shown to stimulate the growth of bifidobacteria and lactobacilli in the human and rat colon. This study investigated the antioxidative effects produced after 48 h in vitro fermentation of unhydrolysed KGM and two hydrolysed KGM fractions (KH1 and KH2 with degree of polymerisation 10 and 5 respectively) by Bifidobacterium adolescentis, B. bifidum, B. breve, B. longum and Lactobacillus acidophilus respectively. The inhibitory effect on conjugated diene formation, ferric-chelating capacity, ,,,-diphenyl-,-picrylhydrazyl (DPPH) radical-scavenging ability and thiobarbituric acid-reactive substances (TBARS) concentration produced by these fermentations were compared with those of oligofructose (OF) fermentation. RESULTS: The fermentation of KGM by each bacterial strain produced higher ferric-chelating capacity of the culture supernatant compared with KH2 or OF fermentation. In contrast, the fermentation of KGM by each bacterial strain led to lower inhibition of conjugated diene formation and lower radical-scavenging ability compared with KH2 fermentation. The fermentation of KH2 produced the lowest amount of TBARS. CONCLUSION: The fermentation of unhydrolysed KGM by colonic lactic acid bacteria in vitro produced antioxidative capacity mainly by preventing the initiation of ferrous ion-induced peroxidation, whereas the fermentation of konjac oligosaccahrides did so by increasing the radical-scavenging ability and eliminating lipid peroxide formation. Copyright © 2008 Society of Chemical Industry [source] Protective effect of phlorotannin components phloroglucinol and eckol on radiation-induced intestinal injury in micePHYTOTHERAPY RESEARCH, Issue 2 2008Changjong Moon Abstract Components of phlorotannin, which were extracted from Ecklonia species, have been reported to have in vitro radioprotective and antioxidative effects. The radioprotective effects of two of the components of phlorotannin, phloroglucinol and eckol, in intestinal stem cells were examined by evaluating their effects on jejunal crypt survival and apoptosis in gamma-irradiated mice. Pretreating the mice (i.p. 20 mg/kg of body weight at 12 and 36 h before irradiation) prior to irradiation with either phloroglucinol or eckol significantly improved the survival of the jejunal crypt (p < 0.001 and p < 0.01 vs irradiation controls at 3.5 days after 8 Gy irradiation, respectively). The administration of phloroglucinol and eckol prior to irradiation protected the intestinal crypts from radiation-induced apoptosis (p < 0.05 vs irradiation controls at 12 h after 1 Gy irradiation). Although the mechanism for this inhibitory effect remains unknown, these results showed that phloroglucinol and eckol might be useful radioprotectors that can defend intestinal stem cells against the oxidative damage caused by gamma-irradiation. Copyright © 2007 John Wiley & Sons, Ltd. [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] Protective effects of melatonin and indole-3-propionic acid against lipid peroxidation, caused by potassium bromate in the rat kidneyCELL BIOCHEMISTRY AND FUNCTION, Issue 6 2006gorzata Karbownik Abstract Potassium bromate (KBrO3) is classified as a carcinogenic agent. KBrO3 induces tumors and prooxidative effects in kidneys. Melatonin is a well known antioxidant and free radical scavenger. Indole-3-propionic acid (IPA), an indole substance, also reveals antioxidative properties. Recently, some antioxidative effects of propylthiouracil (PTU),an antithyroid drug,have been found. The aim of the study was to compare protective effects of melatonin, IPA, and PTU against lipid peroxidation in the kidneys and blood serum and, additionally, in the livers and the lungs, collected from rats, pretreated with KBrO3. Male Wistar rats were administered KBrO3 (110 mg/kg b.w., i.p., on the 10th day of the experiment) and/or melatonin, or IPA (0.0645 mmol/kg b.w., i.p., twice daily, for 10 days), or PTU (0.025% solution in drinking water, for 10 days). The level of lipid peroxidation products,malondialdehyde,+,4-hydroxyalkenals (MDA,+,4-HDA),was measured spectrophotometrically in thyroid homogenates. KBrO3, when injected to rats, significantly increased lipid peroxidation in the kidney homogenates and blood serum, but not in the liver and the lung homogenates. Co-treatment with either melatonin or with IPA, but not with PTU, decreased KBrO3 -induced oxidative damage to lipids in the rat kidneys and serum. In conclusion, melatonin and IPA, which prevent KBrO3 -induced lipid peroxidation in rat kidneys, may be of great value as protective agents under conditions of exposure to KBrO3. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||||||||