The radioprotective effect of Nigella sativa on nitrosative stress in lens tissue in radiation-induced cataract in rat.

OBJECTIVE: The aim of this study was to investigate the antioxidant and radioprotective effects of Nigella sativa oil (NSO) and thymoquinone (TQ) against ionizing radiation-induced cataracts in lens after total cranium irradiation (IR) of rats with a single dose of 5 gray (Gy). MATERIALS AND METHODS: Seventy-four Sprague-Dawley rats were used for the experiment. The rats were randomly divided into six groups. Group A received total cranium IR plus NSO (1 g kg(-1) d(-1)) orally through an orogastric tube. Group B received total cranium IR plus TQ (50 mgkg(-1) d(-1)) daily by intraperitoneal injection. Group C received 5 Gy of gamma IR as a single dose to total cranium plus 1 ml saline. Group D1 just received 1 ml saline. Group D2 just received dimethyl sulfoxide. Group D3 did not receive anything. RESULTS: At the end of the 10th d, cataract developed in 80% of the rats in IR group only. After IR, cataract rate dropped to 20% and 50% in groups which were treated with NSO and TQ, respectively, and was limited at grades 1 and 2. Nitric oxide synthase activity, nitric oxide and peroxynitrite levels in the radiotherapy group were higher than those of all other groups. CONCLUSIONS: The results implicate a major role for NSO and TQ in preventing cataractogenesis in ionizing radiation-induced cataracts in the lenses of rats, wherein NSO were found to be more potent.

The acute effects of interval exercise on oxidative stress and antioxidant status in volleyball players.

BACKGROUND: Volleyball is briefly described as an "interval" sport with both aerobic and anaerobic components. Exercise may influence antioxidant/prooxidant balance, which leads to differences in oxidative stress status between athletes in different sport disciplines, but the results of the previous studies are inconsistent. In this study, we aimed to determine the acute effects of exercise on oxidative stress parameters such as serum total oxidant status (TOS) and total antioxidant status (TAS) levels in volleyball players. METHODS: Thirteen male volleyball players from the same team participated in this study. The volleyball game lasted approximately 95 minutes including warm-up and cool-down periods. Blood samples were taken before the warm-up and after the cool down. Serum TOS and TAS levels were measured. Oxidative stress index (OSI), a predictor of antioxidant/prooxidant balance (TOS/TAS), was also calculated. RESULTS: The following data were revealed as median: TOS 6.84 µmol H2O2 Eq/L (95% CI: 5.80-8.13) and 5.15 (95% CI: 4.20-6.02); TAS 1.96 mmol Trolox Eq/L (95% CI: 1.91-2.08) and 1.95 (95% CI: 1.86-2.00); and OSI indexes, 3.31 (arbitrary unit) (95% CI: 2.84-4.00) and 2.64 (95% CI: 2.26-3.18) before and after the match with respectively. Serum TOS and OSI levels were significantly lower after volleyball match when compared to before (P<0.05). There was no significant difference in serum TAS levels (P>0.05). CONCLUSIONS: In individuals who exercise active sports, TOS level has been found to be decreased while TAS level has not been affected significantly after volleyball match. Our results suggested that volleyball training may not cause oxidative stress in these players. Regular physical exercise especially, volleyball training may provide adequate protection against exercise-induced oxidative stress.

Radioprotective effect of thymoquinone on salivary gland of rats exposed to total cranial irradiation.

BACKGROUND: The purpose of this study was to investigate the radioprotective effects of thymoquinone against radiation-induced damage in the salivary glands of rats exposed to total cranial gamma irradiation. METHODS: Thirty-two Sprague-Dawley rats were divided into 4 groups to test the radioprotective effectiveness of thymoquinone by intraperitoneal injection. An appropriate control group was also studied. Biochemical parameters in liver tissue of rats were determined by spectrophotometer. RESULTS: Glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST), total (enzymatic plus nonenzymatic) superoxide scavenger activity (TSSA), nonenzymatic superoxide scavenger activity (NSSA), and superoxide dismutase (SOD) activities were significantly decreased, whereas xanthine oxidase, nitric oxide synthase activities, malondialdehyde, nitric oxide, and peroxynitrite levels were significantly increased in the irradiation group when compared to the control and sham control groups. CONCLUSION: Results showed that thymoquinone reduces oxidative and nitrosative stress parameters and has antioxidant effects and a free radical scavenging activity.

The effects of Nigella sativa oil, thymoquinone, propolis, and caffeic acid phenethyl ester on radiation-induced cataract.

BACKGROUND: The aim of this study was to investigate the antioxidant and radioprotective effects of propolis, caffeic acid phenethyl ester (CAPE), Nigella sativa oil (NSO), and thymoquinone (TQ) against ionizing radiation-induced cataracts in lens after total cranium irradiation of rats with single dose of 5-Gy cobalt-60 gamma rays. METHODS: A total of 74 Sprague-Dawley rats were divided into 8 groups to test the radioprotective effectiveness of Nigella sativa oil, thymoquine, propolis, or caffeic acid phenethyl ester administered by either orogastric tube or intraperitoneal injection. Appropriate control groups were also studied. RESULTS: Chylack's cataract classification was used in the study. At the end of the tenth day, cataracts developed in 80 % of the rats in the radiotherapy group. After irradiation, cataract rate dropped to 20 % in NSO, 30 % in propolis, 40 % in CAPE, and 50 % in TQ groups and was limited to grade 1 and grade 2. Cataract formation was observed the least in NSO group and the most in TQ group. In the irradiated (IR) group, superoxide dismutase activity was lower, while glutathione peroxidase and xanthine oxidase activities and malondialdehyde level were higher compared with the other groups. Total superoxide scavenger activity and nonenzymatic superoxide scavenger activity were not statistically significant in IR group compared with the other groups. CONCLUSIONS: The findings obtained in the study might suggest that propolis, CAPE, NSO, and TQ could prevent cataractogenesis in ionizing radiation-induced cataracts in the lenses of rats, wherein propolis and NSO were found to be more potent.

The radio-protective effects of caffeic acid phenethyl ester and thymoquinone in rats exposed to total head irradiation.

BACKGROUND: Many cancer patients treated with radiotherapy suffer severe side effects during and after their treatment. The aim of this study was to investigate the effects of irradiation and the addition of caffeic acid phenethyl ester (CAPE) and thymoquinone (TQ) on the oxidant/antioxidant system in the liver tissue of irradiated rats. METHODS: A total of 40 Sprague-Dawley rats were divided into five groups to test the radioprotective effectiveness of thymoquinone and caffeic acid phenethyl ester administered by intraperitoneal injection. Appropriate control groups were also studied. RESULTS: While liver tissue total oxidant status, lipid hydroperoxide level, and oxidative stress index were significantly increased in the irradiated (IR) group, compared with other groups, total antioxidant status, sulfhydryl levels, and paraoxonase (PON) activity were significantly decreased. Ceruloplasmin activity in IR plus TQ and IR groups was higher than the control group. Arylesterase and PON activities in IR plus TQ- and IR plus CAPE-supplemented groups were lower than those of control groups. CONCLUSIONS: TQ and CAPE decrease oxidative stress markers and have antioxidant effects, which also augment antioxidant capacity in the liver tissue of irradiated rats.

Preliminary study: Evaluation of melatonin secretion in children and adolescents with type 1 diabetes mellitus.

OBJECTIVE: Melatonin is an indolamine hormone, synthesized from tryptophan in the pineal gland primarily. Melatonin exerts both antioxidative and immunoregulatory roles but little is known about melatonin secretion in patients with type 1 diabetes mellitus (T1DM). The aim of this study was to measure serum melatonin levels in patients with T1DM and investigates their relationship with type 1 diabetes mellitus. MATERIALS AND METHODS: Forty children and adolescents with T1DM (18 boys and 22 girls) and 30 healthy control subjects (17 boys and 13 girls) participated in the study. All patients followed in Pediatric Endocrinology and Metabolism Unit of Gaziantep University Faculty of Medicine and also control subjects had no hypertension, obesity, hyperlipidemia, anemia, and infection. Blood samples were collected during routine analysis, after overnight fasting. Serum melatonin levels were analyzed with ELISA. RESULTS: There were no statistically significant differences related with age, sex, BMI distribution between diabetic group and control group. Mean diabetic duration was 2.89 ± 2.69 years. The variables were in the equation. Mean melatonin level in diabetic group was 6.75 ± 3.52 pg/ml and mean melatonin level in control group was 11.51 ± 4.74 pg/ml. Melatonin levels were significantly lower in diabetic group compared to controls (P < 0.01). CONCLUSIONS: Melatonin was associated with type 1 diabetes mellitus significantly. Because of the varied roles of melatonin in human metabolic rhythms, these results suggest a role of melatonin in maintaining normal rhythmicity. Melatonin may play role in preventing process of inflammation and oxidative stress.

Increased resistin serum concentrations in patientswith type 1 diabetes mellitus.

OBJECTIVE: Adiponectin, leptin, and resistin are adipokines which play a significant role in the regulation of lipid and carbohydrate metabolism in patients with type 2 diabetes, while little is known about their role in type 1 diabetes mellitus (T1DM). The aim of this study was to measure serum adiponectin, leptin, and resistin levels and to investigate their relationships with some parameters in patients with T1DM and healthy controls. METHODS: Fifty children and adolescents with T1DM (21 boys and 29 girls) and 33 healthy control subjects (18 boys and 15 girls) participated in the study. All subjects were patients followed in the Pediatric Endocrinology and Metabolism Unit of Gaziantep University Faculty of Medicine. None of the subjects had hypertension, obesity, hyperlipidemia, anemia, or infection. Adiponectin, leptin, and resistin levels were analyzed with ELISA. RESULTS: There were no statistically significant differences related with age, sex, pubertal status, or body mass index distribution between the diabetic and control groups. Resistin levels were significantly higher in the diabetic group compared to controls (5.26±3.15 ng/mL vs. 3.50±1.26 ng/mL; p<0.01). CONCLUSION: Of the three investigated adipokines, only resistin was associated with T1DM. Resistin may play a role in the process of inflammation and also in the pathophysiology of T1DM.