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Öğe Alterations in antioxidant enzyme activities in cerebrospinal fluid related with severity of hypoxic ischemic encephalopathy in newborns(Karger, 2005) Gulcan, H; Ozturk, IC; Arslan, SBackground. The antioxidant status of the tissue affected by ischemia-reperfusion is of great importance for the primary endogenous defense against the free-radical-induced injury. Objective: In this study, we aimed to evaluate the relationship between the activities of antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT)] in cerebrospinal fluid (CSF) and severity of hypoxic-ischemic encephalopathy (HIE) in newborns. Methods: Thirty full-term asphyxiated infants (gestational age >37 weeks) and 11 full-term infants (none of whom showed any signs of asphyxia) were included in this study. Activities of SOD, GPX, and CAT in CSF were measured within the first 72 h of life in infants with HIE and controls. Results: Activity of SOD in CSF was significantly higher in infants with HIE compared with controls (p < 0.05). GPX and CAT activities were higher in infants with HIE than they were in controls; however, the differences were not statistically significant (p > 0.05). The activities of GPX and CAT were significantly increased in severe HIE as compared with mild HIE and controls (p < 0.05). Conclusion: Both the duration of the hypoxic-ischemic insult and the severity of HIE modulate elevations of enzymatic activity as an adaptive response to excessive free radical production in CSF in newborn infants with HIE. The activities of antioxidant enzyme alterations in CSIF correspond highly to the severity of HIE, and these patterns may be useful for diagnostic and prognostic purposes. Copyright (C) 2005 S. Karger AG, Basel.Öğe Carbon tetrachloride-induced nephrotoxicity and protective effect of betaine in Sprague-Dawley rats(Elsevier Science Inc, 2003) Ozturk, F; Ucar, M; Ozturk, IC; Vardi, N; Batcioglu, KObjectives. To observe the changes in the antioxidative defense enzymes and to detect the alterations of renal microscopy after carbon tetrachloride (CCl4) administration in rats and to investigate the possible protective effects of betaine against CCl4-induced renal damage. Methods. Thirty-two adult Sprague-Dawley rats were divided into four groups as follows: control group, betaine group, CCl4 group, and CCl4 + betaine group. CCl4 was given subcutaneously at 1 mL/kg. In the CCl4 + betaine group, rats were pretreated with betaine, then exposed to CCl4 at the same dose. Betaine group rats received concentrated betaine solution. The rats were killed and the kidneys taken for enzyme analyses and histologic examination. Glutathione peroxidase, superoxide dismutase, and catalase activities were measured in right kidney homogenates. Left kidneys were processed for light microscopic evaluation. Results. In the CCl4-treated group, significant increases in kidney superoxide dismutase and catalase activities and significant decrease in glutathione peroxidase activity were observed (P < 0.01). These changes were found to be normalized in the CCl4 + betaine group. Betaine did not change the enzyme activities. Exposure to CCl4 resulted in glomerular and tubular alterations in the renal cortex. These alterations were found to be prevented by betaine pretreatment. Conclusions. These results indicate that exposure to CCl4 leads to renal damage in rats and betaine exerts an improvement on nephrotoxic effects of CCl4.Öğe Comparison of chemopreventive effects of Vitamin E plus selenium versus melatonin in 7,12-dimethylbenz(a) anthracene-induced mouse brain damage(Elsevier Sci Ltd, 2004) Batcioglu, K; Karagözler, AA; Ozturk, IC; Genc, M; Bay, A; Ozturk, F; Aydogdu, NIn this work, the protective effect of Vitamin E plus selenium (Vit E + Se) and melatonin against 7,12-dimethylbenz(a)anthracene (7,12DMBA)-induced changes in superoxide dismutase (SOD), glutathione peroxidase (GSHPx), catalase (CAT) and carbonic anhydrase (CA) activities and malonedialdehyde (MDA) levels of mouse brain were compared. 12-month old mice were divided into four groups each including 10 animals. The first group served as control group. The second group was treated with 7,12-DMBA (20 mg/(kg day)). The third group was treated with 7,12-DMBA and Vitamin E (90 mu g/(individual day)) and selenium (1.8 mu g/(individual day)) simultaneously. The fourth group was treated with 7, 12-DMBA and melatonin (4.2 mg/(kg day)) simultaneously. Treatment continued for 21 days after which the mice were sacrificed and brain homogenates were prepared. 7,12-DMBA treated group exhibited significantly decreased levels of brain SOD, GSHPx, CAT and CA activities and increased MDA levels as compared to control. Vitamin E + Se fully or partially restored enzyme inhibition except for SOD. Lipid peroxidation was also reduced in Vitamin E + Se treated group. Melatonin provided a better protection for SOD, GSHPx and CAT, and a plausible protection for CA activity. Protection against lipid peroxidation measured as MDA in melatonin treated group was appreciable although slightly lesser than the protection provided by Vitamin E + Se. The results imply that Vitamin E + Se and melatonin both provide chemoprevention against 7,12-DMBA-induced oxidative stress in mouse brain. (c) 2004 International Society for Preventive Oncology. Published by Elsevier Ltd. All rights reserved.Öğe Investigation of the relationship between nitric oxide metabolites' levels and adenosine deaminase activity in 7,12-dimethylbenz[a]anthracene induced mouse liver(Wiley, 2002) Ozturk, IC; Batcioglu, K7,12-Dimethylbenz[a]anthracene (7,12DMBA) is a member of the polycyclic aromatic hydrocarbons with a severe carcinogenic effect. In this study, nitrate levels and ADA (Adenosine deaminase) activity in the liver homogenates of mice were measured and the effect of free radicals induced by 7,12-DMBA on inducible nitric oxide synthase (iNOS) and ADA activity were investigated. Antioxidant effects of melatonin were also compared. Three groups of mice were included in the study. The first served as control, the second was treated only with 7,12-DMBA and the third was treated with 7,12-DMBA+melatonin. Spectrophotometric methods were used at all measurements. Data were analyzed using Kruskal-Wallis Variance Analysis Test and Mann-Whitney U Test that were applied to the groups. The nitrate concentrations of mouse liver were as follows: 4.98 +/- 0.63 mumol/L in the control group (n = 10), 8.23 +/- 1.58 mumol/L (higher than control group, p < 0.05) in the 7,12-DMBA-treated group (n = 10), and 6.43 +/- 0.57 mumol/L (lower than 7,12-DMBA-treated group, p < 0.05) in the 7,12-DMBA+melatonintreated group (n = 10). Liver ADA activities were measured to be 4.14 +/- 0.674 U/L in the control group, 6.25 +/- 1.261 U/L (higher than control group, p < 0.05) in the 7,12-DMBA-treated group, and 4.93 +/- 0.916 U/L (lower than 7,12-DMBA-treated group, p < 0.05) in the 7,12-DMBA+melatonin-treated group. Differences between free nitrite levels were no significantly. Results demonstrated that nitrate levels and ADA activities were increased by means of free radicals induced by 7,12-DMBA. Melatonin inhibited the 7,12DMBA induced increase that was observed in the activities of ADA enzyme and nitrate levels. It is concluded that determination of ADA activity and nitrate levels can be useful in the assesment of liver damage caused by toxic chemicals. (C) 2002 Wiley Periodicals, Inc.Öğe Lipid peroxidation and antioxidant status in stomach cancer(Taylor & Francis Inc, 2006) Batcioglu, K; Mehmet, N; Ozturk, IC; Yilmaz, M; Aydogdu, N; Erguvan, R; Uyumlu, BBackground: Considerable evidences have linked oxidative damage and cancer. In this article, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) activities, and malondialdehyde (MDA) and nitric oxide metabolites' levels (NOx) were investigated in patients with stomach cancer. Methods: All measurments were done by spectrophotometric techniques. Results: We observed a significant decrease in the activities of SOD and CAT in tumour tissues when compared with control tissues. The different of GSHPx activities and NO metabolite' levels were not statistically significant. MDA levels were significantly increased. Conclusions: We conclude that increased MDA levels and decreased antioxidant enzyme activities can be valuable parameters in assessing the possible risk of cancer.
