Obesity is not a descriptive factor for oxidative stress and viscosity in follicular fluid of in vitro fertilization patients.

BACKGROUND: Obesity's impact on micro-environmental oxidative stress and follicular fluid (FF) viscosity and whether or not it has any effect on in vitro fertilization (IVF) success is a matter of debate. AIMS: In this study, our aim was to evaluate the levels of oxidative stress markers and the FF viscosity in obese and non-obese patients. METHODS: Eighty norm-responder patients undergoing IVF were prospectively grouped according to their body mass indexes (BMI). Group 1 (n = 40) and group 2 (n = 40) had BMI values of ≤24.9 and ≥25.0, respectively. Total sulfhydryl (RSH) levels (nmol/m) and the formation of thiobarbituric acid-reactive substances (malondialdehyde, or MDA) (µmol/ml) in FFs were quantified. For the first time in our study, FF viscosity with changing BMI values was also determined. RESULTS: The mean levels of MDA (µmol/ml) and RSH (nmol/ml) were not significantly different between groups (1.37 ± 0.51; 1.51 ± 0.51; p > 0.05 for MDA and 0.42 ± 0.30; 0.41 ± 0.20; p > 0.05 for RSH, respectively). Similarly, the FF viscosity (centipoise) was not different between groups (1.28 ± 0.28; 1.30 ± 0.19; p < 0.05, respectively). Independent of BMI, no correlation was found between FF levels of oxidative markers and the number of oocytes retrieved or the fertilization rates. CONCLUSIONS: In our study, we found no difference in the levels of follicular oxidative and anti-oxidative markers or the follicular fluid viscosity with changing BMI values. We also demonstrated that the levels of oxidative stress markers and the viscosity of follicular fluid did not affect clinical outcomes.

The evaluation of hormonal and psychological parameters that affect bone mineral density in postmenopausal women.

OBJECTIVE: In this study we aimed to investigate the relationships between serum levels of DHEAS, reproductive hormones and low bone mineral density (BMD) in postmenopausal women. We also examined the relationship between psychological status of patients and their BMD results. PATIENTS AND METHODS: This study included postmenopausal female patients. BMD measurements were performed with dual-energy X-ray absorptiometry (DEXA). Psychological assessments of all cases were performed using the Hamilton Anxiety and Hamilton Depression scales. All patients provided fasting venous blood samples in order to determine serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and DHEAS. RESULTS: There were 33 cases (45.2%) with normal BMD levels and 40 cases (54.8%) with abnormal BMD levels (osteopenia and osteoporosis). DHEAS levels did not show any statistically significant difference according to BMD results (p = 0.431). The Hamilton Anxiety and Depression scores also did not show statistically significant differences in accordance with the BMD results (p = 0.889 and p = 0.706, respectively). CONCLUSIONS: According to our results, anxiety, depression and circulating DHEAS levels are not significantly associated with low levels of BMD, particularly at osteopenic levels. So these parameters are not useful for clinical practice in patients with low BMD in the middle-aged postmenopausal women.

Omega-3 prevents myelin degeneration in rat foetuses exposed to radiation.

The aim of this study is to investigate the protective effect of antioxidant omega-3 fatty acid (FA) on demyelinisation and degeneration of nerves in central and peripheral nervous systems (CNS and PNS) of rat foetuses. 38 pregnant rats weighing 140-155 g were used. Rats were divided into five groups. Group 1: 7 rats exposed to radiation treatment (RT) for 1 hour/day only; Group 2: 7 rats exposed to RT + Omega-3 FA (p.o.) for 1 hour/day; Group 3: 7 rats exposed to RT for 4 hours/day; Group 4: 7 rats exposed to RT + Omega-3 FA (p.o.) for 4 hours/day; and Group 5: 10 rats with no treatment. Nerve injury was induced by whole-body exposure to 20-µT magnetic field. Omega-3 FA was given orally at a dose of 50 mg/kg. After 18 days, foetuses were delivered by the milking method; CNS and PNS were taken out for pathological examination. The degeneration scores of Group 2 were significantly lower than those of Group 1, whereas the degeneration scores of Group 4 were significantly higher than those of Groups 1 and 3. In conclusion, radiation increases demyelinisation and degeneration of nerves in the rat foetuses' CNS and PNS. Omega-3 FA prevents myelin and nerve degeneration in rat foetuses in low-dose radiation exposure.

Adrenal gland volume assessed by magnetic resonance imaging in women with polycystic ovary syndrome.

PURPOSE: To determine adrenal gland volume (AGV) in women with polycystic ovary syndrome (PCOS) by comparison with healthy control subjects and to investigate the relationship between AGV and hormonal status. PATIENTS AND METHODS: AGV was measured on transverse sections of T1-weighted MRI imaging data in 27 PCOS patients and 40 age-matched control subjects for this prospectively designed study. A comparative analysis of AGV in PCOS and controls was performed and possible correlations between AGV and hormonal parameters were evaluated. RESULTS: PCOS patients had significantly larger AGV compared to controls ((11.7±4.4 cm(3), 7.2±1.9 cm(3), respectively, P<0.001). A significant positive correlation was found between total AGV and dehydroepiandrosterone sulfate, 17-OH progesterone, and total and free testosterone levels in the PCOS group (r=+0.51, +0.48, +0.43, +0.62, respectively; P values<0.05). In addition, AGV was significantly negatively correlated with LH and LH/FSH ratio in the PCOS group (r= -0.55, P=0.02; r=-0.51, P=0.01, respectively). CONCLUSIONS: PCOS patients have significantly increased AGV as well as a positive correlation of AGV and androgens. We conclude that the assessment of AGV with MRI shows a significant correlation with the androgenic activity of the gland, and that hypertrophy of the adrenal gland may be involved in the pathogenesis of PCOS.

The importance of antenatal diagnosis of congenital duodenal obstruction.

INTRODUCTION: The aim of this study was to compare the outcome of operated newborns that had an antenatal diagnosis of congenital duodenal obstruction (CDO) with those who had a late diagnosis in the postpartum period. MATERIALS AND METHODS: The newborns that were operated with the diagnosis of CDO in our department were retrospectively recorded. The patients were grouped according to the time of diagnosis; the ones who had an antenatal diagnosis were assigned to group 1, while the ones that had a diagnosis in the postpartum period were assigned to group 2. The groups were compared in terms of their pregnancy weeks at the time of birth, birth weight, additional congenital anomalies, the type of obstruction, the procedures that are applied, the day of operation, the time for oral feeding tolerance, the duration of hospital stay, and pre- and post-operative complications. RESULTS: Fifteen patients with a diagnosis of CDO were operated on in our department between 2009 and 2014. Eight patients were male and seven patients were female. There were nine patients in group 1 and six patients in group 2. The diagnosis was confirmed in group 1 on the first day of the postpartum period. In the subanalysis, five patients had type 1 CDO and four had type 3 CDO in group 1, while five patients had type 1 CDO and one had type 3 CDO in group 2. There was not any complication in group 1 in the pre-operative period, but two patients had aspiration pneumonia and one had dehydration in group 2 pre-operatively. The mean operation day in the postpartum period was 2.34 (±0.5) days in group 1 and 7.17 (±2.04) in group 2. The time for the patient to tolerate oral feeding in the post-operative period was 11.33 (±1.80) in group 1 and 14.83 (±2.48) in group 2. The duration of hospital stay in group 1 was 20.67 (±9.81) days and 24.66 (±4.50) days in group 2. In the post-operative period, chylous ascites occured in a patient in group 1 and the post-operative period was complicated with ileus in one patient in group 2. No mortalities happened in both groups. CONCLUSION: The prenatal diagnosis of CDO affects the pre-operative complication rate, the time for the operation in the postpartum period, the duration to start post-operative oral feeding, and the duration of hospital stay, but does not affect the mortality or the morbidity.

Tear function alterations in patients with polycystic ovary syndrome.

OBJECTIVE: Complaints of dry eye are prevalent worldwide and are known to be associated with insulin resistance (IR) and hyperandrogenism. However, dry eye is often overlooked in the context of polycystic ovary syndrome (PCOS). The aim of the present study was to evaluate whether or not there is any relation between tear functions and PCOS, which is a multifaceted disorder associated with IR or hyperandrogenism. PATIENTS AND METHODS: A total of 35 women with polycystic ovary syndrome (PCOS) were enrolled in this study, along with 27 healthy controls. Body mass index (BMI), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and free testosterone levels on the third day of menstruation were recorded, as well as hirsutism score (using the Ferriman Gallwey scoring system), insulin resistance (homeostasis model assessment), neutrophil-to- lymphocyte ratios (NLR), platelet-to-lymphocyte ratios (PLR), and mean platelet volumes (MPV). A complete ocular examination was followed by administration of the ocular surface disease index (OSDI) questionnaire and Schirmer and tear break-up time (TBUT) tests. RESULTS: Schirmer and OSDI results were similar between groups, but TBUT was significantly lower in the PCOS group (p = 0.002). There were negative correlations between FG score and TBUT test (r = -0.406, p = 0.001) and between NLR and Schirmer test (r = -0.294, p = 0.025). CONCLUSIONS: Although subjective dry eye symptoms do not present in all patients, these results confirm that tear reduction, which can cause further complications in patients with PCOS, can be detected by careful examination and sensitive tests.

Soluble Lectin-Like Oxidized LDL Receptor 1 as a Possible Mediator of Endothelial Dysfunction in Patients With Metabolic Syndrome.

BACKGROUND: Metabolic syndrome (MetS) defines a well-known cluster of metabolic disturbances associated with an increased risk of cardiovascular disease and diabetes. The aim of this study was to examine the distribution of soluble lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (sLOX-1) levels in patients with MetS, possible association of sLOX-1 with oxidized LDL (oxLDL), endothelial nitric oxide synthase (eNOS), nitric oxide (NOx), endothelin-1 (ET-1), paraoxonase 1 (PON1), and arylesterase (ARE) activities, and these parameters compared with healthy controls. METHODS: A total of 55 patients (37 women, 18 men) with MetS and 29 healthy controls (19 women, 10 men) with a body mass index (BMI) less than 25 kg/m(2) were enrolled in the study. RESULTS: sLOX-1, oxLDL, and ET-1 levels were significantly higher in patients with MetS than in control subjects (P = 0.023 P < 0.001, and P < 0.001, respectively). MetS patients have significantly lower eNOS and NOx levels, and PON1 and ARE activities than control subjects (P = 0.017, P < 0.004, P < 0.001, and P = 0.010, respectively). A positive correlation was observed between the sLOX-1 levels and the oxLDL, ET-1, BMI, glucose levels. ET-1 levels also exhibited significant negative correlation with ARE activity. CONCLUSION: sLOX-1 levels are associated with cardiovascular risk factors, such as increased oxLDL, obesity, and diabetes, in patients with MetS. An increased concentration of sLOX-1 could be an early predictor of endothelial damage in MetS. In addition, it appears that oxLDL, ET-1, eNOS, NOx, PON1, and ARE activities may accurately reflect the levels of endothelial dysfunction in MetS patients.

Resveratrol inhibits postoperative adhesion formation in a rat uterine horn adhesion model.

AIM: Adhesion formation is one of the most important problems occuring after pelvic surgery in the majority of women. The aim of this experimental study was to investigate the effects of the antioxidant resveratrol (3,5,4'-o-trihydroxystilbene) on adhesion formation in a rat uterine horn adhesion model. MATERIALS AND METHODS: Thirty Wistar-Albino female rats were randomly divided into three groups with equal numbers. In Group A, 5.9 mg/kg/day resveratrol was applied by the orogastric route for 10 days before and 20 days after surgery. In Group B, resveratrol was given only for 20 days after surgery. In the control group, no drug was applied before or after surgery. A uterine serosal injury was created using a standard technique after laparotomy in all rats. All animals were sacrificed 3 weeks after surgery and intrapelvic adhesions determined macroscopically and microscopically. RESULTS: Adhesion formation, total adhesion score and the severity of adhesions were all significantly lower in both resveratrol treatment groups than in the control group (p < 0.05). Notably, the severity of adhesions was much less in Group A in which the rats received resveratrol before and after surgical operation. CONCLUSIONS: This study suggests that 5 ± 1 mg/kg/day perioperative resveratrol administration is an effective strategy for the prevention of postoperative peritoneal adhesion formation after pelvic surgery in a rat model.

Advanced glycation end products and antioxidant status in nondiabetic and streptozotocin induced diabetic rats: effects of copper treatment.

The effects of Cu(II) supplementation on glycemic parameters, advanced glycation end products (AGEs), antioxidant status (glutathione; GSH and total antioxidant capacity; TAOC) and lipid peroxidative damage (thiobarbituric acid-reactive substances, TBARS) were investigated in streptozotocin (STZ) induced diabetic rats. The study was carried out on Wistar albino rats grouped as control (n = 10), CuCl(2) treated (n = 9), STZ (n = 10) and STZ,CuCl(2) treated (n = 9). STZ was administered intraperitoneally at a single dose of 65 mg/kg and CuCl(2), 4 mg copper/kg, subcutaneously, every 2 days for 60 days. At the end of this period, glucose(mg/dl), Cu(microg/dl), TBARS(micromol/l), TAOC(mmol/l) were measured in plasma, GSH(mg/gHb) in erythrocytes and glycated hemoglobin (GHb)(%) in blood. Plasma AGE-peptides(%) were measured by HPLC flow system with spectrofluorimetric and spectrophotometric detectors connected on-line. Data were analyzed by the non-parametric Kruskal-Wallis and Mann-Whitney U test. In the STZ group glucose, GHb and AGE-peptide levels were all significantly higher than the control group (P < 0.01, P < 0.05, and P < 0.01, respectively). CuCl(2) treated group had significantly lower glucose but significantly higher GHb, TAOC and TBARS levels than the control group (P < 0.05, P < 0.001, P < 0.05 and P < 0.001, respectively). STZ,CuCl(2) treated group had significantly higher GHb, TAOC and TBARS levels compared with the control group (P < 0.001, P < 0.05 and P < 0.05, respectively); but only TAOC level was significantly higher than the STZ group (P < 0.01). This experimental study provides evidence that copper intake increases total antioxidant capacity in both nondiabetic and diabetic states. However despite the potentiated antioxidant defence, lipid peroxidation and glycation enhancing effects of CuCl(2) are evident under nondiabetic conditions.

Is stormwater harvesting beneficial to urban waterway environmental flows?

Urbanization degrades the hydrology and water quality of waterways. Changes to flow regimes include increased frequency of surface runoff, increased peak flows and an increase in total runoff. At the same time, water use in many cities is approaching, and in some cases exceeding, sustainable limits. Stormwater harvesting has the potential to mitigate a number of these detrimental impacts. However, excessive harvesting of stormwater could also be detrimental to stream health. Therefore, a study was undertaken to test whether typical stormwater harvesting scenarios could meet the dual objectives of (i) supplying urban water requirements, and (ii) restoring the flow regime as close as possible to 'natural' (pre-developed). Melbourne and Brisbane, which have different climates, were used along with three land use scenarios (low, medium and high density). Modelling was undertaken for a range of flow and water quality indicators. The results show that using these typical harvesting scenarios helped to bring flow and water quality back towards their pre-developed levels. In some cases, however, harvesting resulted in an over-extraction of flow, demonstrating the need for optimizing the harvesting strategy to meet both supply and environmental flow objectives. The results show that urban stormwater harvesting is a potential strategy for achieving both water conservation and environmental flows.

Oxidative stress in heart tissue of hyperthyroid and iron supplemented rats.

This study was designed to investigate the effect of hyperthyroidism and/or iron supplementation or cardiac oxidative stress parameters--the lipid peroxidation end product glutathione (GSH), glutathione peroxidase (CSH-Px), and superoxide dismutase (CuZnSOD)--in rats. In plasma, ferritin as an indicator of iron status and glutamate oxaloacetate transaminase (GOT) as an indicator of damage to the heart tissue were analyzed. Our findings show that hyperthyroidism increased lipooxidative damage as reflected by higher lipid peroxidation end product levels and elevated antioxidant defense parameters-GSH and GSH-Px. Iron supplementation per se does not affect oxidative stress parameters studied in the euthyroid state. Although iron increased lipid peroxidation in the hyperthyroid state, this effect was less than that seen in euthyroidism. Iron supplementation to hyperthyroid rats significantly lowered plasma ferritin levels, suggesting increased iron elimination with consequently reduced oxidative stress.

Biochemical evaluation of oxidative stress during exercise in patients with coronary heart disease.

The impact of exercise tolerance test on oxidative stress was assessed by thiobarbituric acid reactive substances and markers of antioxidant status, namely Cu Zn superoxide dismutase, glutathione peroxidase, glutathione and vitamin E in blood samples of patients with exertional angina. The study was aimed to differentiate patients with positive exercise test (coronary heart disease patients) from patients with negative exercise test, at rest and peak exercise with respect to the investigated variables. Significantly lower values for both glutathione peroxidase activity and glutathione level were observed in patients after exercise test (p<0.01 and p<0.05, respectively). Only the patients with positive exercise test had significantly lower values for Cu Zn superoxide dismutase, glutathione peroxidase and glutathione, and a significantly higher ratio of thiobarbituric acid reactive substances/glutathione after exercise, as compared to before (p<0.05, p<0.05, p<0.05, p<0.01, respectively). Our findings indicate that the exercise test applied to patients with exertional angina oxidatively stresses the erythrocytes to a greater extent in exercise test (+) patients than in exercise test (-) patients.

Influence of propylthiouracil treatment on oxidative stress and nitric oxide in Basedow disease patients.

Oxidative stress parameters and nitric oxide (NO) values were determined in 27 newly diagnosed Basedow patients before and after 1 mo of propylthiouracil (PTU) therapy and in 15 healthy controls. Basedow patients exhibited increased triiodothyronine (T3) and thyroxine (T4) and decreased thyroid-stimulating hormone (TSH) values compared to controls. Significantly higher thiobarbituric acid-reactive substances (TBARS), NO and glutathione (GSH) levels, and CuZn superoxide dismutase (CuZn SOD) activity were found in Basedow patients in comparison to controls, regardless of sex. Treatment with PTU (3 x 100 mg/d for 30 d) was effective in decreasing T1 and T4 and increasing TSH levels. Significantly decreased NO and TBARS and increased GSH and CuZn SOD levels were observed in PTU-treated Basedow patients compared to pre-PTU administration. PTU-treated patients compared to controls still exhibited significantly higher T3 and lower TSH values and higher NO, TBARS, GSH, and CuZn SOD levels. The induced antioxidant defense and decrease in NO) values in response to PTU therapy emphasizes the role of PTU as an antithyroid drug, where the ability to diminish hyperthyroidism results in decreased catabolism and lower oxidant generation.

Evaluation of oxidative stress in experimental colitis: effects of L-arginine-nitric oxide pathway manipulation.

In this study it was of interest to evaluate the impact of nitric oxide (NO) modulation by administration of arginine/NAME, on oxidative stress in experimental colitis induced by 2,4,6-trinitrobenzenesulfonic acid. Arginine was used to increase NO levels while NAME lowered oxidant levels. Histopathological findings of colon revealed mucosal inflammation in all groups but significantly higher with arginine alone. The levels of NO and of thiobarbituric acid-reactive substances (TBARS, a marker of lipid peroxidation) were observed to be significantly higher in the arginine-administered group compared to glycine, and these levels were found to decrease on administration of NAME to both glycine- and L-arginine-administered groups. Glutathione peroxidase (GSH-Px) activity and glutathione (GSH) levels were significantly higher in arginine administered group compared to glycine. Significantly higher CuZn superoxide dismutase (CuZn-SOD) activity was observed in the L-arginine + L-NAME group compared to arginine. Data show that NO plays a role in oxidant damage found in experimental colitis and that the use of NAME may potentially inhibit injury.

Comparison of oxidative stress indicators in plasma of recent-onset and long-term type 1 diabetic patients.

Oxidative stress was compared in plasma of 15 recently diagnosed (<2 mo) or 15 longstanding (>5 yr) type 1 diabetic patients with 15 healthy volunteers. Lipid peroxidation indices measured in plasma included thiobarbituric acid-reactive substances (TBARS), conjugated dienes, and lipid hydroperoxide (ROOH). The values obtained were corrected for phospholipid to minimize this as a confounding factor. In recently diagnosed diabetics, plasma conjugated lipid dienes were significantly elevated. However, in longstanding diabetics there was a marked increase in TBARS, conjugated dienes, and lipid hydroperoxide levels. Our findings showed increased oxidative stress in type 1 diabetics regardless of metabolic control and that conjugated diene measurement appeared to be the most sensitive bioindicator of oxidant stress in our population.

Lipid peroxidation and antioxidant state after laparoscopic and open cholecystectomy.

OBJECTIVE: To measure the amount of lipid peroxidation and erythrocyte antioxidation in patients undergoing laparoscopic and open cholecystectomy and healthy controls. DESIGN: Non-randomised study. SETTING: University hospital, Istanbul. SUBJECTS: 31 patients, of whom 14 underwent open and 17 laparoscopic cholecystectomy, and 15 healthy controls. INTERVENTIONS: Heparinised blood samples were taken from the patients immediately after operation and from the healthy controls. MAIN OUTCOME MEASURES: Lipid peroxidation index as expressed by thiobarbituric-acid-reactive substances (TBARS) and components of the erythrocyte antioxidant defence system, namely reduced glutathione, reduced glutathione peroxidase (glutathione-Px) and CuZn superoxide dismutase (CuZn SOD) in patients undergoing open or laparoscopic cholecystectomy and healthy controls. RESULTS: All 4 variables were significantly higher in the cholecystectomy groups than in controls (p < 0.001), and laparoscopic cholecystectomy caused significantly less oxidative stress than the open operation (p < 0.001). CONCLUSION: Both types of cholecystectomy cause oxidative stress and lead to an adaptive antioxidant response in the body. However; both oxidative stress and the antioxidant response are more pronounced after traditional open cholecystectomy.

Evaluation of oxidative stress parameters in blood of patients with laryngeal carcinoma.

OBJECTIVES: In this study, plasma lipid peroxidation as assessed by thiobarbituric acid reactive substances and erythrocyte antioxidant status markers namely CuZn superoxide dismutase, glutathione peroxidase, glutathione and plasma levels of vitamin C and E were investigated in 20 patients with larygneal carcinoma and 15 healthy controls. DESIGN AND METHODS: Lipid peroxidation was observed to be significantly higher (0.01 > p > 0.001) in the larynx carcinoma group in comparison to the healthy controls. Both stage I + 11 and stage III carcinoma patients were observed to have significantly higher thiobarbituric acid reactive substances than the control group. A significant difference was found in plasma vitamin E level between the control group and stage I + 11 and stage III carcinoma patients (p < 0.01, 0.05 > p > 0.02, respectively). RESULTS: Our findings reveal the presence of increased lipooxidative damage in laryngeal carcinoma patients, but no change with respect to the endogenous antioxidant components-GSH, GSH Px, and CuZn SOD.

The impact of propylthiouracil therapy on lipid peroxidation and antioxidant status parameters in hyperthyroid patients.

This study was performed on 17 hyperthyroid patients and 15 healthy controls. The patients were under propylthiouracil (PTU) therapy at a dosage of 3 x 100 mg/day for one month. Blood samples, taken at the beginning and on the 30th day of therapy, were analyzed for hormonal parameters (T3, T4, TSH), lipid peroxidation endproduct [thiobarbituric acid reactive substances (TBARS)] and antioxidant status parameters: glutathione (GSH), glutathione peroxidase (GSH-Px) and CuZn superoxide dismutase (CuZn SOD). Hyperthyroid patients were observed to have significantly higher TBARS, GSH and CuZn SOD levels than controls (P < 0.05, P < 0.001, P < 0.001, respectively). PTU therapy caused a relief in oxidative stress as reflected by significantly decreased TBARS levels (P < 0.001) and a selective modification in the antioxidant status parameters: significant decreases in GSH and CuZn SOD levels (P < 0.001) and a significant increase in GSH Px (P < 0.01) activity. Our findings suggest a selective modification of the antioxidative profile in hyperthyroidism. PTU should also be considered as an in vivo antioxidant, in addition to its antithyroid action.

Evaluation of antioxidant status in liver tissues: effect of iron supplementation in experimental hyperthyroidism.

The antioxidant defense system in liver tissue in experimental hyperthyroidism and/or in iron supplementation was investigated. Thyroid hormones (T3, T4, TSH), ferritin (marker of iron status), antioxidant status components (glutathione [GSH], glutathione peroxidase [GSH-Px], superoxide dismutase [SOD]), and serum transaminases (GOT and GPT, both of which are known to be released from damaged hepatocytes), were measured. Hyperthyroidism in rats, induced by L-thyroxine administration, significantly raised SOD activity (p < 0.05), but significantly decreased GSH-Px activity and GSH values (p < 0.001) in the liver. In the L-thyroxine administered and iron supplemented (TI) group, GSH and GSH-Px values of liver tissues were significantly lower than those of control rats (p < 0.05). GSH-Px levels of the TI group were higher (p < 0.001), and SOD levels significantly lower (p < 0.001) than those of the L-thyroxine administered group. We conclude that hyperthyroidism induces SOD activity in liver; ferritin levels increase in hyperthyroidism, contributing to the antioxidant defense system; GSH-Px and GSH levels are decreased significantly in hyperthyroidism either due to inactivation due to increased oxidative stress or to insufficient synthesis; iron supple- and GPT analysis); iron decreases the effect of T4. This must be taken into consideration during iron supplementation.

Biochemical evaluation of oxidative stress in propylthiouracil treated hyperthyroid patients. Effects of vitamin C supplementation.

In this study the impact of vitamin C supplementation on oxidative damage as assessed by thiobarbituric acid reactive substances and markers of antioxidant status: namely Cu/Zn superoxide dismutase, glutathione peroxidase, glutathione reductase and glutathione were investigated in 24 hyperthyroid patients under propylthiouracil therapy (3x100 mg/day) for five days and in 15 healthy controls. Ascorbic acid (1000 mg/day) was given as a supplement for 1 month to both the patients and controls during the study period. Heparinised blood samples were taken at the beginning and the end of one month ascorbic acid supplementation. Comparison of the hyperthyroid patients with the controls revealed higher lipid peroxidation (p<0.001), higher Cu/Zn superoxide dismutase activity (p<0.001), higher glutathione level (p<0.001) and lower glutathione reductase activity (p<0.001). Vitamin C supplementation to hyperthyroid patients caused significant increases in glutathione concentration (p<0.001) and glutathione peroxidase activity (p<0.001), whereas there were significant decreases in glutathione reductase (p<0.001) and Cu/Zn superoxide dismutase activities (p<0.01). Thiobarbituric acid reactive substances and thiobarbituric acid reactive substances/glutathione ratio were significantly decreased (p<0.01). Vitamin C supplementation to euthyroid controls caused significant increases in glutathione concentration (p<0.001) and glutathione peroxidase and Cu/Zn superoxide dismutase activities (p<0.001), whereas there was a significant decrease in glutathione reductase (p<0.001). The thiobarbituric acid reactive substances/glutathione ratio was significantly decreased (p<0.05). Our findings reveal the potentiation of antioxidant status and a relief in oxidative stress in both propylthiouracil treated hyperthyroid patients and controls in response to vitamin C supplementation.