In the present study, it is aimed to investigate oxidant/antioxidant status of plasma and erythro... more In the present study, it is aimed to investigate oxidant/antioxidant status of plasma and erythrocytes from atherosclerotic patients and to establish the possible role of oxidant stress in the formation and progression of atherosclerosis. Antioxidant potential (AOP) values and ...
Background Oxidative and nitrosative stress is well believed to play a role in the pathogenesis o... more Background Oxidative and nitrosative stress is well believed to play a role in the pathogenesis of ischemic stroke. This study aims to evaluate the time course of oxidative and nitrosative stress in ischemic stroke. Methods In total, 27 healthy individuals, 22 individuals with high risk of ischemic stroke due to hypertension and diabetes mellitus, and 20 patients with acute ischemic stroke hospitalized at the Neurology Department of the Kırıkkale University School of Medicine were enrolled in the study. Venous blood was collected at admission (hour 0) and again at hours 24, 48, 72, and 96. Nitric oxide (NO), malondialdehyde (MDA), total oxidative stress (TOS), oxidative stress index (OSI), and total antioxidant status (TAS) were measured and compared among stroke patients and control groups. Results Blood NO was significantly higher in the patient group at 0, 24, 48, and 72 h compared to the healthy and high-risk control groups, and lower at 96 h than at early times within the patie...
To investigate increased oxidative stress in saliva of smokers along with their serum. The case-c... more To investigate increased oxidative stress in saliva of smokers along with their serum. The case-control study was conducted from September to December 2008 in the Department of Biochemistry of the Medical School, Kirikkale University, Kirikkale, Turkey. A blood sample and saliva samples before and after smoking were collected from the smokers, while blood and saliva samples were taken from the controls. All samples were taken concurrently. The samples were measured for total antioxidant capacity, total oxidant stress, oxidative stress index, malondialdehyde, nitric oxide and total sulfhydryl groups. Levels of superoxide dismutase and glutathione peroxidase were also measured on saliva samples. SPSS 13 was used for statistical analysis. Of the 54 subjects in the study, 27(50%) were smokers with a mean age of 28.4 ± 5.42 years, and 27 (50%) were controls with a mean age of 29.7 ± 8.03 years. Total oxidant stress, oxidative stress index, malondialdehyde and nitric oxide levels were found higher in the serum samples of smokers (p < 0.05), and the levels of total sulfhydryl groups in smokers were lower compared with the controls (p < 0.05). Among the smokers, salivary malondialdehyde levels were higher before and after smoking (p < 0.05), glutathione peroxidase levels were lower than the controls, and salivary nitric oxide levels after smoking were higher than both those of the control group and the levels before smoking (p < 0.05). Both acute and chronic increased oxidative conditions may be a significant sign of the destructive effects of smoking. The investigation of disorders in smokers concerning oxidative stress will be beneficial in terms of novel approaches and treatment modalities.
The aim of the present study was to investigate possible involvement of oxidant stress in the ane... more The aim of the present study was to investigate possible involvement of oxidant stress in the anemia of cirrhotic patients and to assess blood antioxidant status of these patients. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) enzyme activities were measured in the erythroctes from patients with liver cirrhosis and from controls. Levels of thiobarbituric acid reagent substance were also measured in the erythrocyte (TBARSe) and plasma (TBARSp) samples of the groups. Lower activities of SOD and GSH-Px were established in the erythrocytes from patients compared with control subjects. No differences were found between erythrocyte TBARS levels of control and patient groups. Plasma TBARS levels were, however, found to be significantly higher in the patient groups compared with controls. Results suggest that although enzymatic antioxidant defense system is significantly reduced in the erythrocytes from cirrhotic patients, this does not lead to further peroxidative reactions in the erythrocytes, possible due to preoxidation of some cellular structures sensitive to peroxidative attacks. There was, however, an important indication of accelerated peroxidative reactions in the plasma of the cirrhotic patients, which possibly resulted from extracellular oxidant stress in these patients.
Brazilian Journal of Anesthesiology (Edicion en Espanol), 2014
Anestesia general; Interleucina; Cirugía; Óxido nítrico; Desflurano Resumen Objetivo: este estudi... more Anestesia general; Interleucina; Cirugía; Óxido nítrico; Desflurano Resumen Objetivo: este estudio investigó los niveles plasmáticos de interleucina-10 y óxido nítrico después de la cirugía para determinar si hay alguna correlación entre esas 2 variables y si diferentes tasas de flujo de anestesia con desflurano influyen en las concentraciones de interleucina-10 y óxido nítrico en la circulación. Materiales y métodos: cuarenta pacientes, entre 18 y 70 años de edad, estado físico ASA I-II, programados para tiroidectomía se incluyeron en el estudio. Intervenciones: los pacientes se dividieron en 2 grupos para recibir 2 flujos diferentes de anestesia con desflurano: flujo alto (grupo FA) y flujo bajo (grupo FB). Mediciones: se extrajeron muestras de sangre al inicio (t 0) y al final (t 1) de la cirugía y después de 24 h (t 2). Los niveles plasmáticos de interleucina-10 y óxido nítrico fueron medidos usando un ensayo de inmunoabsorción conectando un kit de reactivos de Griess, respectivamente. Se evaluaron los parámetros hemodinámicos y respiratorios. Resultados: no hubo diferencia estadísticamente significativa entre los 2 grupos con relación a los niveles de interleucina-10 en los tiempos de medición. Los niveles de interleucina-10 aumentaron igualmente en ambos grupos en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio. En ambos grupos, las concentraciones circulantes de óxido nítrico estaban significativamente reducidas en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio. Sin embargo, el valor de óxido nítrico fue menor en el grupo FA que en el grupo FB en el t 2. No hubo correlación entre los niveles de interleucina-10 y óxido nítrico. Conclusión: el uso clínico de 2 flujos diferentes en anestesia con desflurano puede aumentar los niveles de interleucina-10 tanto en el grupo FA como en el grupo FB; los niveles de las concentraciones circulantes de óxido nítrico estaban significativamente reducidos en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio; no * Autor para correspondencia.
JPMA. The Journal of the Pakistan Medical Association, 2015
To investigate increased oxidative stress in saliva of smokers along with their serum. The case-c... more To investigate increased oxidative stress in saliva of smokers along with their serum. The case-control study was conducted from September to December 2008 in the Department of Biochemistry of the Medical School, Kirikkale University, Kirikkale, Turkey. A blood sample and saliva samples before and after smoking were collected from the smokers, while blood and saliva samples were taken from the controls. All samples were taken concurrently. The samples were measured for total antioxidant capacity, total oxidant stress, oxidative stress index, malondialdehyde, nitric oxide and total sulfhydryl groups. Levels of superoxide dismutase and glutathione peroxidase were also measured on saliva samples. SPSS 13 was used for statistical analysis. Of the 54 subjects in the study, 27(50%) were smokers with a mean age of 28.4 ± 5.42 years, and 27 (50%) were controls with a mean age of 29.7 ± 8.03 years. Total oxidant stress, oxidative stress index, malondialdehyde and nitric oxide levels were fou...
This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determ... more This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determine whether there is a correlation between these two variables and if different desflurane anesthesia flow rates influence nitric oxide and interleukin-10 concentrations in circulation. Forty patients between 18 and 70 years and ASA I-II physical status who were scheduled to undergo thyroidectomy were enrolled in the study. Patients were allocated into two groups to receive two different desflurane anesthesia flow rates: high flow (Group HF) and low flow (Group LF). Blood samples were drawn at the beginning (t0) and end (t1) of the operation and after 24h (t2). Plasma interleukin-10 and nitric oxide levels were measured using an enzyme-linked-immunosorbent assay and a Griess reagents kit, respectively. Hemodynamic and respiratory parameters were assessed. There was no statistically significant difference between the two groups with regard to interleukin-10 levels at the times of measurem...
Canadian journal of surgery. Journal canadien de chirurgie, 1999
To establish the antioxidant status of rat intestinal tissues after ischemia-reperfusion and to d... more To establish the antioxidant status of rat intestinal tissues after ischemia-reperfusion and to determine if pretreatment with an allopurinol and antioxidant vitamin combination gives any protection against mucosal injury. Twenty rats were divided into 4 groups of 5 animals each. Group 1 (control) rats were not subjected to ischemia-reperfusion and received no allopurinol plus vitamin combination; group 2 rats received vitamins C (200 mg/kg) and E (100 mg/kg) and allopurinol (50 mg/kg) combination daily for 3 days preoperatively; group 3 rats were subjected to ischemia-reperfusion only; and group 4 rats were subjected to ischemia-reperfusion and received the vitamin and allopurinol combination. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes, the level of thiobarbituric acid-reagent substances (TBARS) and histologic grading of tissue samples. SOD and GSH-Px activities were decreased, but the CAT activity and TBARS level increased....
Activities of adenosine deaminase, 5'-nucleotidase, xanthine oxidase, superoxide dismutase, g... more Activities of adenosine deaminase, 5'-nucleotidase, xanthine oxidase, superoxide dismutase, glutathione peroxidase and catalase enzymes were measured in cancerous and non-cancerous adjacent colorectal tissues from 10 patients. Activities of DNA turn-over enzymes (ADA, 5'NT and XO) were found increased and those of free-radical metabolizing enzymes (SOD, GSH-Px and CAT) decreased in cancerous tissues compared with those of non-cancerous adjacent ones. Malondialdehyde (MDA) concentrations in cancerous tissues were also found higher than those of non-cancerous tissues, which indicated accelerated lipid peroxidation in the cancerous tissues. In the correlation analysis, disordered enzymatical relations were observed between the enzymes of both metabolic pathways. Results suggest that activities of purine metabolizing enzymes increase to cope with accelerated purine metabolism in cancerous tissues and, enzymatic antioxidant defense potential of cancerous tissues decreases due to ...
Arginase (Arg) activity in seminal plasma and sperm cells from infertile men and healthy fertile ... more Arginase (Arg) activity in seminal plasma and sperm cells from infertile men and healthy fertile donors was measured. There were no statistically meaningful dierences in seminal plasma Arg activity between the two groups whereas sperm cells from oligospermic infertile men had a higher Arg activity compared with the controls. Some important correlations were established between sperm count and Arg activity (negative values) and sperm motility and Arg activity (positive values) in both sperm cells and plasma samples from infertile men. Results suggest that the arginine-nitric oxide pathway within sperm cells from oligospermic infertile men is disturbed by enhanced Arg activity. We think that this may play a part in sperm dysfunction and male infertility.
Possible molecular mechanisms leading to cyclosporine-induced hepatotoxicity has not been cleared... more Possible molecular mechanisms leading to cyclosporine-induced hepatotoxicity has not been cleared yet. Therefore, investigation of antioxidant status of hepatic tissues exposed to cyclosporine A (CsA) and of free radical involvement in the CsA-induced hepatotoxicity seems of importance. For this aim, 20 rabbits were used in the study. In each group (control, CsA, CsA plus vitamin and, vitamin only) there were 5 animals. CsA was given orally (25 mgykgyday) for 10 days. Vitamins E (100 mgykgy day) and C (200 mgykgyday) combination was injected intramuscularly. After 10th day, animals were killed, and livers were prepared for the enzymatic assays. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) and, malondialdehyde (MDA) levels were determined in the supernatant fractions. Lowered SOD, unchanged GSH-Px and, increased CAT activities and MDA levels were detected in hepatic tissues of rabbits treated with CsA as compared with controls. In the CsA plus vitamin group, SOD activity was found to be higher, GSH-Px and CAT activities unchanged and MDA levels lower than the CsA group. In the vitamin-treated group, all of the enzyme activities were higher than the controls but MDA levels were unchanged. Correlation analysis revealed some significant differences between the groups. Results suggest that cyclosporine impairs the antioxidant defense system and thus, leads to oxidant stress and peroxidation in rabbit hepatic tissues. It has been established that this process can be prevented by antioxidant vitamin supplementation.
Enzymatic antioxidant defense system and antioxidant defense potential (AOP) were studied in kidn... more Enzymatic antioxidant defense system and antioxidant defense potential (AOP) were studied in kidney tissue from rabbits treated with cyclosporine (CsA, 25 mg/kg/day), antioxidant vitamins (E, 100 mg/kg/day plus C, 200 mg/ kg/day), and CsA plus antioxidant vitamins, and in kidney tissue from control animals. Although no change was observed in superoxide dismutase (SOD) activity, glutathione peroxidase (GSH-Px) and catalase (CAT) activities were found decreased in kidney tissue exposed to CsA for 10 days compared with control tissue. The level of thiobarbituric acid-reagent substances (TBARS) was higher and antioxidant defense potential (AOP) lower in the CsA-treated group compared with the other groups. Histopathological examination reveals important subcellular damage in the renal tissue from the animals treated with CsA. Antioxidant vitamin therapy caused full improvement in the enzyme activities, TBARS levels and AOP, but the subcellular damage was partly ameliorated in the CsA plus vitamin group. Results suggest that CsA impairs the antioxidant defense system and reduces the antioxidant defense potential in the renal tissue. Antioxidant vitamin treatment protects the tissue in part against toxic effects of the drug.
Antioxidant defense potential, malondialdehyde (MDA) levels, and relative hydroxyl radical (OH.) ... more Antioxidant defense potential, malondialdehyde (MDA) levels, and relative hydroxyl radical (OH.) concentrations were measured in order to establish the effects of extracorporeal shock wave lithotripsy (ESWL) on free radical production and antioxidant defense potential of the rabbit kidney tissues. Electron microscopic examination was also performed to observe ultrastructural changes. The antioxidant defense potential of the ESWL-treated tissues was found to be reduced, and the MDA levels increased as compared with controls. Vitamin (vitamin E plus C combination) pretreatment ameliorated antioxidant defense potential in part, prevented increases in MDA levels in the ESWL-treated tissues, and increased the antioxidant defense potential in the control kidney tissues. After ESWL, a significant amount of OH. radical was measured in the affected tissue. This revealed the source of oxidant stress and peroxidation reactions in the ESWL-treated kidney tissue. Vitamin pretreatment caused significant reduction in the OH. radical concentration. In the electron microscopic investigation, some significant subcellular changes, such as endothelial injury, loss of foot processes, damage of glomerular basal membrane, etc., were observed in the ESWL-treated renal tissue slices. Vitamin pretreatment to a great extent prevented formation of these subcellular changes. Our results suggest that the antioxidant capacity of the kidney tissue was reduced after ESWL treatment and that the tissue was exposed to oxidant stress. Vitamin pretreatment exerted significant protection against the radical damage.
This study aims to elucidate plasma oxidant/antioxidant status in patients with rheumatoid arthri... more This study aims to elucidate plasma oxidant/antioxidant status in patients with rheumatoid arthritis (RA). Fasting blood samples were obtained from 24 patients with RA and 20 control subjects. Antioxidant potential (AOP) value, nonenzymatic superoxide radical scavenger activity (NSSA), and malondialdehyde (MDA) levels were measured to establish plasma oxidant/antioxidant status in the patient and control groups. Patients with RA had lower AOP and NSSA but higher MDA levels than those of the control subjects, which was an indication of reduced antioxidant capacity and oxidant stress in these patients. Results suggest that the antioxidant system is impaired and peroxidation reactions are accelerated in patients with RA. We suppose that therapeutic use of some antioxidants may be beneficial in this regard.
In the present study, it is aimed to investigate oxidant/antioxidant status of plasma and erythro... more In the present study, it is aimed to investigate oxidant/antioxidant status of plasma and erythrocytes from atherosclerotic patients and to establish the possible role of oxidant stress in the formation and progression of atherosclerosis. Antioxidant potential (AOP) values and ...
Background Oxidative and nitrosative stress is well believed to play a role in the pathogenesis o... more Background Oxidative and nitrosative stress is well believed to play a role in the pathogenesis of ischemic stroke. This study aims to evaluate the time course of oxidative and nitrosative stress in ischemic stroke. Methods In total, 27 healthy individuals, 22 individuals with high risk of ischemic stroke due to hypertension and diabetes mellitus, and 20 patients with acute ischemic stroke hospitalized at the Neurology Department of the Kırıkkale University School of Medicine were enrolled in the study. Venous blood was collected at admission (hour 0) and again at hours 24, 48, 72, and 96. Nitric oxide (NO), malondialdehyde (MDA), total oxidative stress (TOS), oxidative stress index (OSI), and total antioxidant status (TAS) were measured and compared among stroke patients and control groups. Results Blood NO was significantly higher in the patient group at 0, 24, 48, and 72 h compared to the healthy and high-risk control groups, and lower at 96 h than at early times within the patie...
To investigate increased oxidative stress in saliva of smokers along with their serum. The case-c... more To investigate increased oxidative stress in saliva of smokers along with their serum. The case-control study was conducted from September to December 2008 in the Department of Biochemistry of the Medical School, Kirikkale University, Kirikkale, Turkey. A blood sample and saliva samples before and after smoking were collected from the smokers, while blood and saliva samples were taken from the controls. All samples were taken concurrently. The samples were measured for total antioxidant capacity, total oxidant stress, oxidative stress index, malondialdehyde, nitric oxide and total sulfhydryl groups. Levels of superoxide dismutase and glutathione peroxidase were also measured on saliva samples. SPSS 13 was used for statistical analysis. Of the 54 subjects in the study, 27(50%) were smokers with a mean age of 28.4 ± 5.42 years, and 27 (50%) were controls with a mean age of 29.7 ± 8.03 years. Total oxidant stress, oxidative stress index, malondialdehyde and nitric oxide levels were found higher in the serum samples of smokers (p < 0.05), and the levels of total sulfhydryl groups in smokers were lower compared with the controls (p < 0.05). Among the smokers, salivary malondialdehyde levels were higher before and after smoking (p < 0.05), glutathione peroxidase levels were lower than the controls, and salivary nitric oxide levels after smoking were higher than both those of the control group and the levels before smoking (p < 0.05). Both acute and chronic increased oxidative conditions may be a significant sign of the destructive effects of smoking. The investigation of disorders in smokers concerning oxidative stress will be beneficial in terms of novel approaches and treatment modalities.
The aim of the present study was to investigate possible involvement of oxidant stress in the ane... more The aim of the present study was to investigate possible involvement of oxidant stress in the anemia of cirrhotic patients and to assess blood antioxidant status of these patients. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) enzyme activities were measured in the erythroctes from patients with liver cirrhosis and from controls. Levels of thiobarbituric acid reagent substance were also measured in the erythrocyte (TBARSe) and plasma (TBARSp) samples of the groups. Lower activities of SOD and GSH-Px were established in the erythrocytes from patients compared with control subjects. No differences were found between erythrocyte TBARS levels of control and patient groups. Plasma TBARS levels were, however, found to be significantly higher in the patient groups compared with controls. Results suggest that although enzymatic antioxidant defense system is significantly reduced in the erythrocytes from cirrhotic patients, this does not lead to further peroxidative reactions in the erythrocytes, possible due to preoxidation of some cellular structures sensitive to peroxidative attacks. There was, however, an important indication of accelerated peroxidative reactions in the plasma of the cirrhotic patients, which possibly resulted from extracellular oxidant stress in these patients.
Brazilian Journal of Anesthesiology (Edicion en Espanol), 2014
Anestesia general; Interleucina; Cirugía; Óxido nítrico; Desflurano Resumen Objetivo: este estudi... more Anestesia general; Interleucina; Cirugía; Óxido nítrico; Desflurano Resumen Objetivo: este estudio investigó los niveles plasmáticos de interleucina-10 y óxido nítrico después de la cirugía para determinar si hay alguna correlación entre esas 2 variables y si diferentes tasas de flujo de anestesia con desflurano influyen en las concentraciones de interleucina-10 y óxido nítrico en la circulación. Materiales y métodos: cuarenta pacientes, entre 18 y 70 años de edad, estado físico ASA I-II, programados para tiroidectomía se incluyeron en el estudio. Intervenciones: los pacientes se dividieron en 2 grupos para recibir 2 flujos diferentes de anestesia con desflurano: flujo alto (grupo FA) y flujo bajo (grupo FB). Mediciones: se extrajeron muestras de sangre al inicio (t 0) y al final (t 1) de la cirugía y después de 24 h (t 2). Los niveles plasmáticos de interleucina-10 y óxido nítrico fueron medidos usando un ensayo de inmunoabsorción conectando un kit de reactivos de Griess, respectivamente. Se evaluaron los parámetros hemodinámicos y respiratorios. Resultados: no hubo diferencia estadísticamente significativa entre los 2 grupos con relación a los niveles de interleucina-10 en los tiempos de medición. Los niveles de interleucina-10 aumentaron igualmente en ambos grupos en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio. En ambos grupos, las concentraciones circulantes de óxido nítrico estaban significativamente reducidas en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio. Sin embargo, el valor de óxido nítrico fue menor en el grupo FA que en el grupo FB en el t 2. No hubo correlación entre los niveles de interleucina-10 y óxido nítrico. Conclusión: el uso clínico de 2 flujos diferentes en anestesia con desflurano puede aumentar los niveles de interleucina-10 tanto en el grupo FA como en el grupo FB; los niveles de las concentraciones circulantes de óxido nítrico estaban significativamente reducidos en los tiempos t 1 y t 2 en comparación con las concentraciones en el preoperatorio; no * Autor para correspondencia.
JPMA. The Journal of the Pakistan Medical Association, 2015
To investigate increased oxidative stress in saliva of smokers along with their serum. The case-c... more To investigate increased oxidative stress in saliva of smokers along with their serum. The case-control study was conducted from September to December 2008 in the Department of Biochemistry of the Medical School, Kirikkale University, Kirikkale, Turkey. A blood sample and saliva samples before and after smoking were collected from the smokers, while blood and saliva samples were taken from the controls. All samples were taken concurrently. The samples were measured for total antioxidant capacity, total oxidant stress, oxidative stress index, malondialdehyde, nitric oxide and total sulfhydryl groups. Levels of superoxide dismutase and glutathione peroxidase were also measured on saliva samples. SPSS 13 was used for statistical analysis. Of the 54 subjects in the study, 27(50%) were smokers with a mean age of 28.4 ± 5.42 years, and 27 (50%) were controls with a mean age of 29.7 ± 8.03 years. Total oxidant stress, oxidative stress index, malondialdehyde and nitric oxide levels were fou...
This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determ... more This study investigated interleukin-10 and nitric oxide plasma levels following surgery to determine whether there is a correlation between these two variables and if different desflurane anesthesia flow rates influence nitric oxide and interleukin-10 concentrations in circulation. Forty patients between 18 and 70 years and ASA I-II physical status who were scheduled to undergo thyroidectomy were enrolled in the study. Patients were allocated into two groups to receive two different desflurane anesthesia flow rates: high flow (Group HF) and low flow (Group LF). Blood samples were drawn at the beginning (t0) and end (t1) of the operation and after 24h (t2). Plasma interleukin-10 and nitric oxide levels were measured using an enzyme-linked-immunosorbent assay and a Griess reagents kit, respectively. Hemodynamic and respiratory parameters were assessed. There was no statistically significant difference between the two groups with regard to interleukin-10 levels at the times of measurem...
Canadian journal of surgery. Journal canadien de chirurgie, 1999
To establish the antioxidant status of rat intestinal tissues after ischemia-reperfusion and to d... more To establish the antioxidant status of rat intestinal tissues after ischemia-reperfusion and to determine if pretreatment with an allopurinol and antioxidant vitamin combination gives any protection against mucosal injury. Twenty rats were divided into 4 groups of 5 animals each. Group 1 (control) rats were not subjected to ischemia-reperfusion and received no allopurinol plus vitamin combination; group 2 rats received vitamins C (200 mg/kg) and E (100 mg/kg) and allopurinol (50 mg/kg) combination daily for 3 days preoperatively; group 3 rats were subjected to ischemia-reperfusion only; and group 4 rats were subjected to ischemia-reperfusion and received the vitamin and allopurinol combination. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes, the level of thiobarbituric acid-reagent substances (TBARS) and histologic grading of tissue samples. SOD and GSH-Px activities were decreased, but the CAT activity and TBARS level increased....
Activities of adenosine deaminase, 5'-nucleotidase, xanthine oxidase, superoxide dismutase, g... more Activities of adenosine deaminase, 5'-nucleotidase, xanthine oxidase, superoxide dismutase, glutathione peroxidase and catalase enzymes were measured in cancerous and non-cancerous adjacent colorectal tissues from 10 patients. Activities of DNA turn-over enzymes (ADA, 5'NT and XO) were found increased and those of free-radical metabolizing enzymes (SOD, GSH-Px and CAT) decreased in cancerous tissues compared with those of non-cancerous adjacent ones. Malondialdehyde (MDA) concentrations in cancerous tissues were also found higher than those of non-cancerous tissues, which indicated accelerated lipid peroxidation in the cancerous tissues. In the correlation analysis, disordered enzymatical relations were observed between the enzymes of both metabolic pathways. Results suggest that activities of purine metabolizing enzymes increase to cope with accelerated purine metabolism in cancerous tissues and, enzymatic antioxidant defense potential of cancerous tissues decreases due to ...
Arginase (Arg) activity in seminal plasma and sperm cells from infertile men and healthy fertile ... more Arginase (Arg) activity in seminal plasma and sperm cells from infertile men and healthy fertile donors was measured. There were no statistically meaningful dierences in seminal plasma Arg activity between the two groups whereas sperm cells from oligospermic infertile men had a higher Arg activity compared with the controls. Some important correlations were established between sperm count and Arg activity (negative values) and sperm motility and Arg activity (positive values) in both sperm cells and plasma samples from infertile men. Results suggest that the arginine-nitric oxide pathway within sperm cells from oligospermic infertile men is disturbed by enhanced Arg activity. We think that this may play a part in sperm dysfunction and male infertility.
Possible molecular mechanisms leading to cyclosporine-induced hepatotoxicity has not been cleared... more Possible molecular mechanisms leading to cyclosporine-induced hepatotoxicity has not been cleared yet. Therefore, investigation of antioxidant status of hepatic tissues exposed to cyclosporine A (CsA) and of free radical involvement in the CsA-induced hepatotoxicity seems of importance. For this aim, 20 rabbits were used in the study. In each group (control, CsA, CsA plus vitamin and, vitamin only) there were 5 animals. CsA was given orally (25 mgykgyday) for 10 days. Vitamins E (100 mgykgy day) and C (200 mgykgyday) combination was injected intramuscularly. After 10th day, animals were killed, and livers were prepared for the enzymatic assays. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) and, malondialdehyde (MDA) levels were determined in the supernatant fractions. Lowered SOD, unchanged GSH-Px and, increased CAT activities and MDA levels were detected in hepatic tissues of rabbits treated with CsA as compared with controls. In the CsA plus vitamin group, SOD activity was found to be higher, GSH-Px and CAT activities unchanged and MDA levels lower than the CsA group. In the vitamin-treated group, all of the enzyme activities were higher than the controls but MDA levels were unchanged. Correlation analysis revealed some significant differences between the groups. Results suggest that cyclosporine impairs the antioxidant defense system and thus, leads to oxidant stress and peroxidation in rabbit hepatic tissues. It has been established that this process can be prevented by antioxidant vitamin supplementation.
Enzymatic antioxidant defense system and antioxidant defense potential (AOP) were studied in kidn... more Enzymatic antioxidant defense system and antioxidant defense potential (AOP) were studied in kidney tissue from rabbits treated with cyclosporine (CsA, 25 mg/kg/day), antioxidant vitamins (E, 100 mg/kg/day plus C, 200 mg/ kg/day), and CsA plus antioxidant vitamins, and in kidney tissue from control animals. Although no change was observed in superoxide dismutase (SOD) activity, glutathione peroxidase (GSH-Px) and catalase (CAT) activities were found decreased in kidney tissue exposed to CsA for 10 days compared with control tissue. The level of thiobarbituric acid-reagent substances (TBARS) was higher and antioxidant defense potential (AOP) lower in the CsA-treated group compared with the other groups. Histopathological examination reveals important subcellular damage in the renal tissue from the animals treated with CsA. Antioxidant vitamin therapy caused full improvement in the enzyme activities, TBARS levels and AOP, but the subcellular damage was partly ameliorated in the CsA plus vitamin group. Results suggest that CsA impairs the antioxidant defense system and reduces the antioxidant defense potential in the renal tissue. Antioxidant vitamin treatment protects the tissue in part against toxic effects of the drug.
Antioxidant defense potential, malondialdehyde (MDA) levels, and relative hydroxyl radical (OH.) ... more Antioxidant defense potential, malondialdehyde (MDA) levels, and relative hydroxyl radical (OH.) concentrations were measured in order to establish the effects of extracorporeal shock wave lithotripsy (ESWL) on free radical production and antioxidant defense potential of the rabbit kidney tissues. Electron microscopic examination was also performed to observe ultrastructural changes. The antioxidant defense potential of the ESWL-treated tissues was found to be reduced, and the MDA levels increased as compared with controls. Vitamin (vitamin E plus C combination) pretreatment ameliorated antioxidant defense potential in part, prevented increases in MDA levels in the ESWL-treated tissues, and increased the antioxidant defense potential in the control kidney tissues. After ESWL, a significant amount of OH. radical was measured in the affected tissue. This revealed the source of oxidant stress and peroxidation reactions in the ESWL-treated kidney tissue. Vitamin pretreatment caused significant reduction in the OH. radical concentration. In the electron microscopic investigation, some significant subcellular changes, such as endothelial injury, loss of foot processes, damage of glomerular basal membrane, etc., were observed in the ESWL-treated renal tissue slices. Vitamin pretreatment to a great extent prevented formation of these subcellular changes. Our results suggest that the antioxidant capacity of the kidney tissue was reduced after ESWL treatment and that the tissue was exposed to oxidant stress. Vitamin pretreatment exerted significant protection against the radical damage.
This study aims to elucidate plasma oxidant/antioxidant status in patients with rheumatoid arthri... more This study aims to elucidate plasma oxidant/antioxidant status in patients with rheumatoid arthritis (RA). Fasting blood samples were obtained from 24 patients with RA and 20 control subjects. Antioxidant potential (AOP) value, nonenzymatic superoxide radical scavenger activity (NSSA), and malondialdehyde (MDA) levels were measured to establish plasma oxidant/antioxidant status in the patient and control groups. Patients with RA had lower AOP and NSSA but higher MDA levels than those of the control subjects, which was an indication of reduced antioxidant capacity and oxidant stress in these patients. Results suggest that the antioxidant system is impaired and peroxidation reactions are accelerated in patients with RA. We suppose that therapeutic use of some antioxidants may be beneficial in this regard.
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