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Öğe The activities of purine catabolizing enzymes in plasma and bronchial washing fluid in patients with lung cancer and pneumonia(Pergamon-Elsevier Science Ltd, 2001) Akyol, O; Gökbulut, I; Köksal, N; Akin, H; Özyurt, H; Yildirim, Z[Abstract Not Available]Öğe The activities of serum adenosine deaminase and xanthine oxidase enzymes in Behcet's disease(Elsevier Science Bv, 2002) Sögüt, S; Aydin, E; Elyas, H; Aksoy, N; Özyurt, H; Totan, Y; Akyol, ÖBackground: Adenosine deaminase (AD) and xanthine oxidase (XO) are enzymes of purine catabolism that catalyze the conversion of adenosine to inosine, deoxyadenosine to deoxyinosine, hypoxanthine to xanthine and xanthine to Uric acid, respectively. AD is known to be an important enzyme in the maturation and function of T lymphocytes. The aim of this prospective study was to evaluate whether there are changes in serum AD activity as an index of T lymphocyte function in Behcet's disease (BD) which is known as having T cell-mediated immune response. Methods: A total of 32 patients and 26 sex- and age-matched healthy control subjects were analysed for AD and XO activities. The patients with BD were divided into two subgroups: BD with and without eye lesions. Twelve patients with complete BD and four patients with incomplete BD had eye complications. AD and XO activities in serum were measured with spectrophotometric methods. Re vults: There was a remarkable increase in AD activity and moderate increase in XO in patients with BD compared to controls indicating T cell activation and increased maturation. Serum AD activity of complete BD was higher than that of incomplete BD. There was no difference it) XO activity between the subgroups of BD. Significant positive correlation was found between AD and XO in BD, although there was no correlation in control group. Conclusions: The results indicate that increased AD and XO activities may provide an additional benefit for the diagnosis of BD and subtyping of the disease as having eye complication or not and complete and incomplete BD. Further studies are needed to bring to light the exact mechanism of AD and XO activity elevation. (C) 2002 Elsevier Science B.V. All rights reserved.Öğe Caffeic acid phenethyl ester changes the indices of oxidative stress in serum of rats with renal ischaemia-reperfusion injury(Wiley, 2001) Özyurt, H; Irmak, MK; Akyol, Ö; Sögüt, SOxygen-derived free radicals have been implicated in the pathogenesis of renal injury after ischaemia-reperfusion. Caffeic acid phencthyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. To investigate whether treatment with either CAPE or alpha-tocopherol modifies the levels of the endogenous indices of oxidant stress, we examined their effects on an in vivo model of renal ischaemia-reperfusion injury in rats. CA-PE at 10 mu mol kg(-1) or alpha-tocopherol at 10 mg kg(-1) was administered intraperitoneally before reperfusion. Acute administration of both CAPE and alpha-tocopherol altered the indices of oxidative stress differently in renal ischaemia-reperfusion injury. Copyright (C) 2001 John Wiley & Sons, Ltd.Öğe Changes in nitric oxide levels and antioxidant enzyme activities may have a role in the pathophysiological mechanisms involved in autism(Elsevier Science Bv, 2003) Sögüt, S; Zoroglu, SS; Özyurt, H; Yilmaz, HR; Özugurlu, F; Sivasli, E; Yetkin, ÖBackground: There is evidence that oxygen free radicals play an important role in the pathophysiology of many neuropsychiatric disorders. Although it has not been investigated yet, several recent studies proposed that nitric oxide (NO) and other parameters related to oxidative stress may have a pathophysiological role in autism. Methods: We assessed the changes in superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and thiobarbituric acid-reactive substances (TBARS) levels in plasma as well as NO levels in red blood cells (RBC) in patients with autism (n = 27) compared to age- and sex-matched normal controls (n = 30). Results: In the autistic group, increased RBC NO levels (p < 0.0001) and plasma GSH-Px activity (p < 0.0001) and unchanged plasma TBARS levels and SOD activity were detected. Conclusions: These findings indicate a possible role of increased oxidative stress and altered enzymatic antioxidants, both of which may be relevant to the pathophysiology of autism. (C) 2003 Published by Elsevier Science B.V.Öğe Cisplatin-induced acute renal failure is ameliorated by erdosteine in a dose-dependent manner(Wiley, 2004) Özyurt, H; Yildirim, Z; Kotuk, M; Yilmaz, HR; Yagmurca, M; Iraz, M; Sögüt, SThe aim of this study was to investigate the optimum dosage of erdosteine to ameliorate cisplatin-induced nephrotoxicity. Three different doses of erdosteine at 25, 50 and 75 mg kg(-1) were studied in rats. Intraperitoneal administration of 7 mg kg(-1) cisplatin led to acute renal failure, as indicated by kidney histology and increases in plasma creatinine and blood urea nitrogen (BUN) levels. At 5 days after cisplatin injection the BUN level was increased significantly from 15.1 +/- 4.3 to 126.7 +/- 152.6 mg dl(-1) and plasma creatinine levels increased from 0.37 +/- 0.005 to 1.68 +/- 1.9 mg dl(-1). When the rats were administered 50 and 75 mg kg(-1) erdosteine 24 h before cisplatin injection that was continued until sacrifice (total of 6 days), the BUN and creatinine levels remained similar to control levels and the grade of histology was similar. Erdosteine at doses of 50 and 75 mg kg(-1) ameliorates cisplatin-induced renal failure. The optimum dose of erdosteine may be 50 mg kg(-1) in this study. Copyright 2004 John Wiley Sons, Ltd.Öğe Comparison of serum nitric oxide, malondialdehyde levels, and antioxidant enzyme activities in Behcet's disease with and without ocular disease(Karger, 2004) Aydin, E; Sögüt , S; Özyurt, H; Özugurlu, F; Akyol, ÖObjective: The pathogenesis of Behcet's disease ( BD) may be related to excessive production of reactive oxygen species, activated neutrophils, and T lymphocytes. The goal of this prospective study was to investigate whether there is any relationship among the oxidant/ antioxidant system and nitric oxide ( NO) and malondialdehyde (MDA) levels in patients with BD and its subtypes: complete Behcet's disease (CBD) and incomplete Behcet's disease (ICBD), with or without ocular disease. Methods: Thirty-two patients and 26 age- and sex-matched healthy control subjects were evaluated for NO and MDA levels and antioxidant enzyme activities. The patients with BD were divided into two subgroups: those with and without ocular disease. Twelve patients with CBD and 4 patients with ICBD had ocular disease. The serum NO level was determined by Griess reaction. The MDA level was detected by thiobarbituric acid reaction. Superoxide dismutase ( SOD) and glutathione peroxidase (GSH-Px) activities in serum were analyzed with spectrophotometric methods. Results: Increased MDA levels but decreased GSH-Px activities in plasma were observed in BD patients with all subtypes, as compared with controls. Concerning the presence of ocular disease and the subtype ( CBD or ICBD) compared with each other, there were no significant differences in MDA or NO serum levels and SOD or GSH-Px enzyme activities. Conclusions: Serum NO levels and SOD enzyme activities were not significantly changed in patients with BD and its subtypes; however, a remarkable decrease of GSH-Px enzyme activity and increase of MDA levels were found. Copyright (C) 2004 S. Karger AG, Basel.Öğe The effect of caffeic acid phenethyl ester on ischemia-reperfusion injury in comparison with ?-tocopherol in rat kidneys(Springer-Verlag, 2001) Irmak, MK; Koltuksuz, U; Kutlu, NO; Yagmurca, M; Özyurt, H; Karaman, A; Akyol, ÖOxygen-derived free radicals have been implicated in the pathogenesis of renal injury after ischemia-reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant and anti-inflammatory properties. To determine whether CAPE offers any advantage over alpha -tocopherol, we compared their effects on an in vivo model of renal ischemia-reperfusion injury in rats. CAFE at 10 mu mol/kg or alpha -tocopherol at 10 mg/kg was administered intraperitoneally before reperfusion. Acute administration of CAFE suppressed ischemia-reperfusion induced renal lipid peroxidation and tissue injury more than alpha -tocopherol. CAFE may therefore offer a therapeutic advantage in acute injury settings.Öğe Effects of caffeic acid phenethyl ester and epidermal growth factor on the development of caustic esophageal stricture in rats(W B Saunders Co, 2001) Koltuksuz, U; Mutus, HM; Kutlu, R; Özyurt, H; Çetin, S; Karaman, A; Gürbüz, NBackground/Purpose: An experimental study was performed to modify the healing response in caustic esophageal burns to prevent stricture development. Two different agents with different modes of actions, caffeic acid phenethyl ester (CAPE) and epidermal growth factor (EGF), were studied. CAPE has antiinflammatory, immunomodulatory, antioxidant, and antimitotic properties. EGF has known properties in supporting wound healing and in protecting esophagus from injuries. Methods: The model described by Gehanno and its modification by Liu was used to create standard esophageal burns with 50% NaOH. The study was performed with 76 rats in 4 main groups (sham, CAPE, EGF, and control) and 2 subgroups in each for 5 and 28 days of observation. Efficacy of treatment was assessed in 28-day subgroups by measuring weight gain, contrast esophagograms on day 27, histologic evaluation by measuring stenosis index (wall thickness/lumen diameter), and collagen deposition, and biochemically by determining tissue hydroxy proline (OHP) content. Results: In the end of the study, increase rates of mean body weights of the animals in the 28-day subgroups were as follows: sham, 30%; CAPE, 23%; EGF, 22%; and control, 14%. Although all the animals in subgroups significantly gained weight, the mean weight gain was significantly low in controls when compared with sham, CAPE, and EGF groups (P < .05). Contrast esophagograms on day 27 showed no stenosis in the sham, mild stenosis in CAPE and EGF, and severe stenosis with proximal dilatation in controls. Stenosis indices of the subgroups were as follows: sham, 0.29; CAPE, 0.41; EGF, 0.41; control, 0.84. Index was significantly higher in controls (P < .05). Collagen accumulation scores in the esophageal wall were as follows: Sham, 0.0; CAPE, 0.87; EGF, 0.30; control, 2.70. Scores also were significantly higher in controls (P < .05). Tissue (OHP) levels were as follows (mg/g dry tissue): Sham, 1.48; CAPE, 1.53; EGF, 1.90; control, 4.01. Production of OHP was significantly higher in controls. Conclusions: The results of the parameters in the study indicate that administration of CAPE and EGF has beneficial effects in the prevention of caustic esophageal strictures. Those effects of CAPE may occur through its antiinflammatory, immunomodulatory, and antioxidant properties, and EGF may occur through its induced proliferative properties on the esophagus. Copyright (C) 2001 by WB. Saunders Company.Öğe Evidence that the activities of erythrocyte free radical scavenging enzymes and the products of lipid peroxidation ape increased in different forms of schizophrenia(Springernature, 2001) Herken, H; Uz, E; Özyurt, H; Sögüt, S; Virit, O; Akyol, ÖIn order to examine antioxidant status and lipid peroxidation in schizophrenia patients, activities of three free radical scavenging enzymes (superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT)), and the level of thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation have been studied in red blood cells. Schizophrenic patients were divided into three groups (disorganized (n = 21), paranoid (n = 26) and residual types (n = 18)) to determine differences between subgroups. SOD, CAT and GSH-Px activities in the control group were found to be 1461.0 +/- 248.6 U g(-1) Hb, 148.2 +/- 59.3 k g(-1) Hb and 25.87 +/- 4.25 U g(-1) Hb, respectively. We found no significant differences in SOD activities between study and control groups. There was a significant increase in SOD activity in the residual group compared to the paranoid group (P < 0.005). CAT activity was found to be increased in disorganized (148%), paranoid (147%), and residual (165%) groups compared to the control group. GSH-Px activity was markedly increased in the study groups except the paranoid group. Statistically significant (3-4 fold) increases in TBARS levels of red blood cells were found in all the study groups. It is proposed that antioxidant status may be changed in schizophrenia and thus may induce lipid peroxidation. Therefore, oxidative stress may have a pathophysiological role in all the subtypes of schizophrenia.Öğe In vivo evidence suggesting a role for purine-catabolizing enzymes in the pathogenesis of cisplatin-induced nephrotoxicity in rats and effect of erdosteine against this toxicity(Wiley, 2004) Sögüt, S; Kotuk, M; Yilmaz, HR; Ulu, R; Özyurt, H; Yildirim, ZThe aim of this experimental study was to investigate the possible role of adenosine deaminase (AD) and xanthine oxidase (XO) in the pathogenesis of cisplatin-induced nephrotoxicity and the effect of erdosteine in decreasing the toxicity. The intraperitoneal injection of cisplatin (7m kg(-1) body weight) induced a significant increase in plasma creatinine level and blood urea nitrogen (BUN), and plasma and damaged renal tissue activities of AD and XO in rats. Co-treatment with erdosteine (10 mg kg(-1) day(-1)) attenuated the increase in the plasma creatinine and BUN levels, and significantly prevented the increase in tissue and plasma AD and XO activities (P < 0.05). The results of this study revealed that XO and AD may play an important role in the pathogenesis of cisplatin-induced nephrotoxicity. The potent free radical scavenger erdosteine may have protective potential in this process and it will become a promising drug in the prevention of this undesired side-effect of cisplatin. but further studies are needed to illuminate the exact protection mechanism of erdosteine against cisptatin-induced nephrotoxicity. Copyright (C) 2004 John Wiley Sons, Ltd.Öğe The indices of endogenous oxidative and antioxidative processes in plasma from schizophrenic patients The possible role of oxidant/antioxidant imbalance(Pergamon-Elsevier Science Ltd, 2002) Akyol, Ö; Herken, H; Uz, E; Fadillioglu, E; Ünal, S; Sögüt, S; Özyurt, HThere is great evidence in recent years that oxygen free radicals play an important role in the pathophysiology of schizophrenia. The present study was performed to assess the changes in plasma nitric oxide (NO) and thiobarbituric acid-reactive substances (TBARS) levels, and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and xanthine oxidase (XO) activities in schizophrenic patients compared to age- and sex-matched normal controls. A hundred patients with schizophrenia and 51 healthy volunteers were included in the study. XO, SOD, and GSH-Px activities as well as NO and TBARS levels were estimated by standard biochemical techniques in the plasma of normal healthy controls and schizophrenia patients. In schizophrenia, increased plasma XO activity (P<.0001) and NO levels (P<.0001), decreased SOD activity (P<.0001), and unchanged GSH-Px activity were detected compared to control group. Plasma TBARS levels were increased in schizophrenic patients (P<.01), especially in the residual subtype. TBARS levels in nonsmoker schizophrenic patients were found to be higher than nonsmoker controls. Although TBARS levels in both patients and controls were found to be higher in smokers as compared to nonsmokers, it was not statistically significant. No effects of duration of the illness, gender, and low and high dose of daily neuroleptic treatment equivalent to chlorpromazine on oxidant and antioxidant parameters were observed. Because the dose and the duration of treatment with drugs have no influence on the results, it can be interpreted that the findings are more likely to be related mainly to the underlying disease. These findings indicated a possible role of increased oxidative stress and diminished enzymatic antioxidants, both of which may be relevant to the pathophysiology of schizophrenia. On the other hand, increased NO production by nitric oxide synthetases (NOSs) suggests a possible role of NO in the pathophysiological process of schizophrenia. These findings may also suggest some clues for the new treatment strategies with antioxidants and NO synthase (NOS) inhibitors in schizophrenia. (C) 2002 Elsevier Science Inc. All rights reserved.Öğe Inhibitory effect of caffeic acid phenethyl ester on bleomycine-induced lung fibrosis in rats(Elsevier, 2004) Özyurt, H; Sögüt, S; Yildirim, Z; Kart, L; Iraz, M; Armutçu, F; Temel, IBackground: Pulmonary fibrosis (PF) induced by anticancerogenic bleomycin (BLM) is one of the more common side effects encountered during cancer treatment. It has been suggested in the last decades that the main responsible agent in PF is reactive oxygen species which were generated also in normal physiological conditions in the human body. In this experimental study, we investigated the preventive or attenuating effects of caffeic acid phenethyl ester (CAPE) that has been demonstrated to have anti-inflammatory, cytocytatic, anti cancerogenic, antiprolipherative and antioxidant effects on BLM-induced PF. Methods: Thirty-six Sprague-Dawley rats were divided randomly into four groups as sham operation, BLM, BLM + vitamin E (vit E), and BLM + CAPE groups. BLM (7.5 mg/kg, single dose) was applied intratracheally, and CAPE and vit E intraperitoneally in the appropriate groups. At the end of the fibrosis processes, lung tissues were removed and the levels of tissues hydroxyproline (OH-proline), malondialdehyde (MDA) and NO as well as the activities of superoxide dismutase (SOD), catalase (CAT) and myeloperoxidase (MPO) were determined. Also, the weights of the rats were recorded at 7th and 14th days of the experiments. Results: BLM application to the rats resulted in a significant increase in the OH-proline level as compared to the controls. Administration of CAPE and vit E led to the remarkable reduction of total lung OH-proline levels compared to the rats treated with BLM alone (p < 0.0001). There were a decreases in antioxidant enzyme (SOD and CAT) activities while an increase in MPO activity in BLM group was found vs. the control group (p < 0.0001). CAPE had a regulator effect on these parameters: the increase in CAT and SOD activities and the decrease in MPO activity were seen after CAPE application. NO, MDA and OH-proline levels were increased in BLM group vs. the control group. CAPE was more effective in decreasing the tissue levels of NO, MDA and OH-proline than vit E. MPO activity, as a good marker of neutrophil sequestration to the tissues, in the BLM group was decreased by CAPE approximately to the control group. Conclusion: We suggest that CAPE is more effective on the prevention of BLM-induced fibrosis via antioxidant and free radical scavenger properties than vit E at the doses used in the present study. CAPE has some attenuating effects on BLM-induced PF affecting both oxidant and antioxidant systems as well as neutrophils sequestration. (C) 2003 Elsevier B.V. All rights reserved.Öğe Maternal serum and amniotic fluid hydroxyproline levels in neural tube defects(Karger, 2003) Özyurt, H; Totan, A; Sahin, S; Kilinç, C; Sögüt, S; Akyol, ÖObjective: The present study was aimed to evaluate the alterations of maternal serum and amniotic fluid OH-proline levels in neural tube defects (NTD). Methods: 38 patients and 23 control subjects were selected from the patients followed up by the Departments of Genetics and Antenatal Care, Zekai Tahir Burak Women's Health, Education and Research Hospital. Amnion fluid and blood samples were synchronously obtained from NTD and control subjects. OH-proline levels were detected spectrophotometrically. Results: Amniotic fluid CH-proline levels were found to be increased in NTID patients compared to control subjects (p < 0.05). There was no statistically significant difference in serum OH-proline levels between the groups. Conclusion: The results showed an increase in amniotic fluid OH-proline levels in NTD compared to the control group. It may be suggested that the increased OH-proline levels reflect increased collagen turnover in NTD patients. Indeed, amniotic fluid OH-proline levels may be a candidate as an additional diagnostic parameter in NTD. Copyright (C) 2003 S. Karger AG, Basel.Öğe Potential role of dietary ?-3 essential fatty acids on some oxidant/antioxidant parameters in rats' corpus striatum(Elsevier Sci Ltd, 2003) Sarsilmaz, M; Songur, A; Özyurt, H; Kus, I; Özen, OA; Özyurt, B; Sögüt, SOmega-3 (omega-3) is an essential fatty acid (EFA) found in large amounts in fish oil. It contains eicosapentaenoic acid and docosahexaenoic acid (DHA). DHA is one of the building structures of membrane phospholipids of brain and necessary for continuity of neuronal functions. Evidences support the hypothesis that schizophrenia may be the result of increased reactive oxygen species mediated neuronal injury. Recent reports also suggest the protective effect of omega-3 EFA against neuropsychiatric disorders including schizophrenia. This study proposed to assess the changes in antioxidant enzyme and oxidant parameters in the corpus striatum (CS) of rats fed with omega-3 EFA diet (0.4 g/kg/day) for 30 days. Eight control rats and nine rats fed with omega-3 were decapitated under ether anesthesia, and CS was removed immediately. Thiobarbituric acid-reactive substances (TBARS) and nitric oxide (NO) levels as well as total superoxide dismutase (t-SOD) and xanthine oxidase (XO) enzyme activities in the CS were measured. Rats treated with omega-3 EFA had significantly lower values of TBARS (P < 0.001), NO (P < 0.002) and XO (P < 0.005) whereas higher values of t-SOD enzyme activity (P < 0.002) than the control rats. These results indicate that omega-3 EFA rich fish oil diet reduces some oxidant parameters in CS. This may be revealed by means of reduced CS TBARS levels as an end product of lipid peroxidation of membranes in treated rats. Additionally, reduced XO activity and NO levels may support this notion. On the other hand, although the mechanism is not clear, omega-3 EFA may indirectly enhance the activity of antioxidant enzyme t-SOD. Taken together, this preliminary animal study provides strong support for a therapeutic effect of omega-3 EFA supplemented to classical neuroleptic regimen in the treatment of schizophrenic symptoms and tardive dyskinesia. (C) 2003 Elsevier Ltd. All rights reserved.Öğe The protective role of caffeic acid phenethyl ester (CAPE) on testicular tissue after testicular torsion and detorsion(Springer, 2002) Uz, E; Sögüt, S; Sahin, S; Var, A; Özyurt, H; Güleç, M; Akyol, ÖTesticular artery occlusion causes an enhanced formation of reactive oxygen species, which contributes to the pathophysiology of tissue damage. Here, we have investigated the effects of caffeic acid phenethyl ester (CAPE), a new antioxidant and antiinflammatory agent, in rats subjected to testicular torsion/detorsion (T/D). Thirty-five male rats were divided into four groups: sham operation group (n = 8), torsion group (n = 9), T/ D + saline group (n = 9) and T/D + CAPE group (n = 9). Rats, except the sham operation group, were subjected to left unilateral torsion (720degrees rotation in the clockwise direction) without including the epididymis. After torsion (2 h) and detorsion (4 h) periods, rats were sacrificed and bilateral orchidectomy was performed. Testis tissues were washed with cold saline solution, cut into small pieces with scissors, placed into glass bottles and homogenised in four volumes of ice-cold Tris-HCl buffer. Clear supernatant fluid was used for biochemical analyses. Treating rats with CAPE (applied at 10 mumol/kg, 30 min prior to T/D) attenuated the testicular injury, as well as the increase in the tissue levels of myeloperoxidase and thiobarbituric acid-reactant substances (TBARS) caused by T/D in the testis. Testis tissues showed a significant increase in glutathione peroxidase (GSH-Px) activity compared to the torsion group when CAPE was applied. Taken together, our results clearly demonstrate that CAPE treatment exerts a protective effect on testicular T/D, and part of this effect may be due to inhibiting the neutrophil-mediated cellular injury.Öğe Red blood cell nitric oxide levels in patients with schizophrenia(Elsevier Science Bv, 2001) Herken, H; Uz, E; Özyurt, H; Akyol, Ö[Abstract Not Available]Öğe Role of caffeic acid phenethyl ester, an active component of propolis, against cisplatin-induced nephrotoxicity in rats(Wiley, 2004) Özen, S; Akyol, Ö; Iraz, M; Sögüt, S; Özugurlu, F; Özyurt, H; Odaci, EWe have investigated the effect of caffeic acid phenethyl ester (CAPE) on cisplatin-induced nephrotoxicity in rats. Administration of a single dose of cisplatin resulted in the elevation of blood area nitrogen and creatinine in serum, as well as nitric oxide in kidney tissue of rats. Cisplatin also caused reduction of catalase (P < 0.0001), superoxide dismutase (P = 0.149) and glutathrone peroxidase (P < 0.0001) activities in kidney tissue. Although cisplatin caused elevation in malondialdehyde levels and myeloperoxidase activities in kidney tissue, they were not statistically significant. Caffeic acid phenethyl ester was found to be protective against cisplatin-induced antioxidant enzyme reductions. Treatment with free-radical scavenger CAPE attenuated the increase in plasma blood area nitrogen and kidney nitric oxide levels, and showed histopathological protection against cisplatin-induced acute renal failure. Extensive epithelial cell vacuolization, swelling, desquamation and necrosis were observed in the kidney of the cisplatin-treated rat. There were also larger tubular lumens in cisplatin-treated rats than those of the control and the CAPE groups. Caffeic acid phenethyl ester caused a marked reduction in the extent of tubular damage. It is concluded that administration of cisplatin imposes an oxidative stress to renal tissue and CAPE confers protection against the oxidative damage associated with cisplatin. This mechanism may be attributed to its free-oxygen-radical scavenging activity. Copyright (C) 2004 John Wiley Sons, Ltd.Öğe Testicular nitric oxide levels after unilateral testicular torsion/detorsion in rats pretreated with caffeic acid phenethyl ester(Springer-Verlag, 2000) Koltuksuz, U; Irmak, MK; Karaman, A; Uz, E; Var, A; Özyurt, H; Akyol, ÖNitric oxide (NO) plays an important role in modulating blood flow in normal and in several pathological conditions, and its levels seem to change with ischemia-reperfusion injuries. Caffeic acid phenethyl ester (CAPE), an active component of propolis, exhibits antioxidant properties. This experimental study was designed to determine the changes in NO levels and the effect of CAPE on NO levels after testicular torsion/ detorsion in rats. Thirty-five adult male albino rats were divided into four groups: sham operation (n = 8), torsion (n = 9), saline/detorsion (n = 9), and CAPE/detorsion (n = 9). Rats in the sham operation group were killed after the testes were handled without torsion. Rats in the torsion group were killed after 720 degrees clockwise testicular torsion for 2 h. CAPE was administered 30 min before detorsion in the CAPE/detorsion group and saline was administered in the saline/detorsion group. After 4 h of testicular detorsion in both of these groups, the rats were killed and bilateral orchiectomy was performed to determine the tissue levels of NO. The level of NO in the torsion group (113.77 +/- 33.18 nmol/g protein) was significantly higher than that of the sham operation group (64.53 +/- 29.64 nmol/g protein). In the saline/detorsion group, the NO level (31.26 +/- 12.58 nmol/g protein) was significantly lower than in the torsion and sham operation groups. CAPE administration in the CAPE/detorsion group seemed to raise the NO level (72.63 +/- 23.87 nmol/g protein) above the level of the sham operation group. Contralateral testes were not affected by the torsion/detorsion processes performed on the ipsilateral testes. These results show that NO levels increase with torsion and decrease with detorsion. CAPE administration seems to increase tissue NO levels and this may be important for protecting the testes from torsion/detorsion injuries.Öğe Tissue xanthine oxidase activity and nitric oxide levels after spinal cord ischemia/reperfusion injury in rabbits(Wiley, 2002) Sahin, S; Sögüt, S; Özyurt, H; Uz, E; Ilhan, A; Akyol, ÖCaffeic acid phenethyl ester exhibits antioxidant properties. This experimental study was designed to determine the effect of CAPE on nitric NO level and XO activity after reperfusion injury of spinal cord. New Zealand white rabbits were undergone aortic occlusion. CAPE, methylprednisolone or saline were injected intraperitoneally before surgical intervention. Animals were subjected to 21 min of crossclamp time. At the end of occlusion time, the clamps were removed and restoration of the blood flow was verified visually. Animals in sham group underwent a surgical procedure similar to the other groups but the aorta was not occluded. Spinal cord specimens were obtained to determine the tissue levels of NO and XO activity. Both XO activity and NO level in ischemia group were significantly higher than those of sham group (p = 0.0005 and 0.0003, respectively). MP and CAPE had no effect on XO activity after reperfusion. These two agents decreased NO levels nearly to that of sham group after reperfusion. There were no differences between MP and CAPE on reducing NO level. These results suggest that rabbits with ischemia-reperfusion injury in spinal cord have increased cord concentrations of nitrite and nitrate that are indicative of endogenous overproduction of NO. CAPE may be regarded as an agent that protects spinal cord from ischemia-reperfusion injury.
