Circulating lipid peroxidation and antioxidant status in cervical cancer patients: a case-control study

Objectives: The present case-control study was conducted to investigate the status of circulating lipid peroxidation and the enzymic and nonenzymic antioxidants of cervical cancer patients.

Design and methods: Plasma thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and the levels of antioxidants such as reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione-S-transferase (GST), superoxide dismutase (SOD), vitamin C and vitamin E were estimated in circulation of thirty patients and an equal number of age matched normal subjects as control.

Results: Significantly elevated levels of plasma TBARS and CD and significantly lowered levels of GSH, GPx, GST, SOD vitamin C and vitamin E were observed in cervical cancer patients as compared to controls. Our study reveals increased lipid peroxidation and possible breakdown of antioxidant status in patients with cervical carcinoma.

Conclusion: These results indicate that low levels of GSH, GPx, GST, SOD, vitamin E and vitamin C in the circulation of cervical cancer patients may be due to their increased utilization to scavenge lipid peroxides as well as their sequestration by tumor cells. Malnutrition may also be a significant cause for the increased prevalence of cervical cancer in women with a low socioeconomic status.     

Lipid peroxidation and antioxidative status in beta-thalassemia major patients with or without hepatitis C virus infection.

BACKGROUND: Information pertaining to the lipid peroxidation and antioxidative status of patients with beta-thalassemic major, with or without hepatitis C virus infection, has been scanty. METHODS: We report here the results of our efforts in the evaluation of lipid peroxidative status, antioxidants, and vitamin A, E and C levels in the sera of a group of patients (n=42) with transfusion-dependent beta-thalassemic major with or without HCV infection. RESULTS: Firstly, plasma thiobarbituric acid reactive substance, a lipid peroxidation product, in these patients was found to be increased significantly when compared to the disease-free controls (p<0.05). Conversely, levels of plasma vitamins A, E and C were all shown to be drastically reduced as compared to the disease-free controls (p<0.01). In parallel with these data, we also found that HCV infection did play some role in aggravating the depletion of plasma vitamin E and C levels in the beta-thalassemic patients. In contrast, HCV infection did not seem to alter the levels of reduced glutathione (GSH) as well as antioxidant enzyme activities including superoxide dismutase and GSH peroxidase. CONCLUSIONS: Taken together, our data indicate that excessive lipid peroxidation and a profound depletion of plasma vitamin A, E and C levels exist in patients with beta-thalassemic major. These data suggest that antioxidant supplementation to the patients for the purpose of alleviating the oxidative stress may be warranted.     

Antioxidant profile in the circulation of patients with fibroadenoma and adenocarcinoma of the breast

OBJECTIVES: To correlate the extent of lipid peroxidation with the antioxidant status in the circulation of patients with fibroadenoma and adenocarcinoma of the breast. DESIGN AND METHODS: Ten fibroadenoma and thirty breast cancer patients and an equal number of age- and sex- matched normal subjects were chosen for the study. Lipid peroxidation as evidenced by thiobarbituric acid reactive substances (TBARS) and the status of the antioxidants superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione S-transferase (GST) ascorbic acid and vitamin E were estimated. RESULTS: Enhanced lipid peroxidation with concomitant depletion of antioxidants was observed in breast cancer patients as compared to normal subjects and fibroadenoma patients (p < 0.05). A similar pattern of changes was seen in fibroadenoma patients as compared to corresponding normal subjects (p < 0.05). CONCLUSION: This study has revealed an imbalance in the redox status in patients with fibroadenoma and adenocarcinoma of the breast.     

The effect of vitamin E supplementation on antioxidant enzyme activities and lipid peroxidation levels in hemodialysis patients

BACKGROUND: This study has been undertaken to investigate the possible alterations of oxidant/antioxidant status in uremic patients undergoing hemodialysis (HD) and the effects of vitamin E supplementation. METHODS: Erythrocyte antioxidant enzyme activities [glutathione peroxidase (GSHPx), superoxide dismutase (SOD) and catalase (CAT)] and thiobarbituric acid reactive substance (TBARS) concentrations as a measure of lipid peroxidation in HD patients have been determined and compared with healthy controls. The patient group consisted of 36 uremic patients 21-75 years of age undergoing maintenance HD three times weekly for an average of 41 months. The efficiency of Vitamin E therapy in dialysis patients was also assessed by re-evaluating antioxidant status of the same patients after supplementation of the vitamin E in a dosage of 600 mg/daily for 14 weeks. RESULTS: A significant decrease in the activities of erythrocyte SOD, CAT and GSHPx and a significant increase in TBARS concentrations were found in patient group compared to control group (p<0.001). A significant correlation between GSHPx activities and duration of HD therapy was also observed (r=-0.46, p<0.01). Vitamin E supplementation caused an increase in GSHPx and SOD activities and a decrease in TBARS concentrations. A slight but not significant increase in CAT activity was also observed by Vitamin E. CONCLUSIONS: The results suggest the presence of an oxidative activity and the possible preventive role of Vitamin E therapy in uremic patients undergoing HD.     

Nitric oxide synthase inhibition by L-NAME in streptozotocin induced diabetic rats: impacts on oxidative stress

The effects of nitric oxide synthase (NOS) inhibition by Nw-nitro-L-arginine methyl ester (L-NAME) administration on oxidative stress parameters were investigated in streptozotocin (STZ) induced diabetic rats. Lipid peroxidation as reflected by thiobarbituric acid reactive substances (TBARS) was insignificantly higher in diabetic rats. Plasma NO2+NO3 values (p < 0.05) and erythrocyte CuZn superoxide dismutase (CuZn SOD) and glutathione peroxidase (GSH Px) activities were significantly higher (p < 0.01, p < 0.001, respectively) in diabetic rats. L-NAME administration to diabetic rats caused significantly lower CuZn SOD and GSH Px activities (p < 0.01) and NO2+NO3 values (p < 0.001), whereas a significantly higher GSH level (p < 0.01). TBARS/GSH ratio was significantly higher in diabetic rats than controls (p < 0.05) and significantly lower in L-NAME administered diabetic rats than diabetic rats (p < 0.05). This experimental study highlightens the importance of NOS inhibition by L-NAME in the attenuation of oxidative stress in STZ diabetic rats.     

Plasma antioxidants and lipid peroxidation products in Duchenne muscular dystrophy

Lipid peroxidation (LPX) products in plasma were elevated in Duchenne muscular dystrophy (DMD) patients (n = 9) compared with an age- and sex-matched group of controls (n = 10). Trichloroacetic acid-precipitable thiobarbituric acid-reactive substances (TBARS) were increased by 35% (p less than 0.01), conjugated dienes by 77% (p less than 0.02) and fluorescent pigments (FP) by 70% (p less than 0.001). Plasma alpha-tocopherol was significantly decreased, by 50%, in DMD compared with healthy subjects (p less than 0.002). In conjunction with the finding of others of a deficiency in DMD of the plasma lipoproteins which normally transport vitamin E to the tissues, this may contribute to the increased LPX seen in the disease especially if muscle damage also liberates free Fe2+. The major circulating antioxidant protein, caeruloplasmin (CP), was significantly increased (p less than 0.001) by 25-30% in DMD patients compared with both adult and young male controls. In DMD patients only, this increase is correlated with the concentration of TBARS and FP suggesting that increased LPX may be a trigger for CP synthesis.     

Blood oxidative stress status in patients with macrophagic myofasciitis.

The study aimed at determining the presence of an oxidative stress in patients with macrophagic myofasciitis (MMF), a new inflammatory myopathy with suspected toxic etiology related to aluminium hydroxide-containing vaccines. A total of 30 MMF patients (nine males, 21 females; aged 42+/-14 years), whose diagnosis was confirmed by deltoid biopsy, have been included and compared to 38 sex- and age-matched healthy control subjects (10 males, 28 females; aged 43+/-8 years). The blood oxidative stress status has been evaluated by assaying six parameters: plasma lipid peroxidation products (thiobarbituric acid-reactive substances: TBARS) and antioxidant defense systems: plasma vitamin E and glutathione peroxidase (GSH-Px) activity, erythrocyte GSH-Px and Cu,Zn-superoxide dismutase (SOD) activities. Plasma selenium was also determined as a trace element essential to the activity of GSH-Px. Statistical significance was evaluated by the Mann-Whitney test. Plasma GSH-Px activity, selenium and vitamin E concentration were significantly lower in MMF group than in controls (P=0.004, P=0.003 and P=0.009, respectively), with a positive correlation in MMF patients between plasma GSH-Px activity and selenium concentration (rho=0.0001). The other parameters of oxidative stress did not significantly differ between both groups. A macrophage activation could occur in MMF, consequently to chronic stimulation by aluminium-containing vaccines, and could participate to the lower values of selenium and vitamin E observed in comparison with controls. Nevertheless, since no deficiency in these elements has been observed, no supplementation is to be considered.     

Effects of vitamin E supplementation on blood antioxidants levels in patients with Behçet’s disease

Behçet’s disease (BD) is known for many years, yet its etiology remains unknown. In BD, the increased production of reactive oxygen species from activated neutrophils may reduce concentrations of antioxidant vitamins and enzymes in plasma and red blood cells (RBC). Vitamin E is an important fat soluble antioxidant and its role on antioxidant parameters of BD is unclear. The study was undertaken to evaluate the role of vitamin E on lipid peroxidation (MDA) levels, antioxidant vitamin and enzyme concentrations in plasma and RBC in patients with BD. There were three groups i.e., control, patient and treatment groups with twenty-five subjects in each. Nonsmoking patients with BD, patient group, was compared with an equal number of healthy control subjects (control group). Blood samples were taken from both control and patient groups and then oral vitamin E was daily supplemented to the patients with BD for six weeks (treated group). At the end of six weeks, blood was taken from the treated group once more.

RBC and plasma MDA levels, serum neopterin, complement system (C₃ and C₄), ASO, CRP, rheumatoid factor, plasma lipoprotein (a), total cholesterol concentrations and erythrocyte sedimentation rate were higher in the patient group than in the control group, but they were lower in the treatment group than in the patient group. While vitamins A, E and β-carotene concentrations in plasma, catalase, glutathione peroxidase activities and reduced glutathione levels in RBC and plasma were lower in patient group than in the controls, they were found to be higher in the treatment group than in the patient group.

These results provide some evidence for a potential role of increased lipid peroxidation and decreased enzymatic and non enzymatic antioxidants in BD by its inflammatory character and vitamin E which may strengthen the antioxidant defense system, and may contribute to the treatment of BD.     

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.     

Effects of vitamin E supplementation on blood antioxidants levels in patients with Behçet's disease

Behçet’s disease (BD) is known for many years, yet its etiology remains unknown. In BD, the increased production of reactive oxygen species from activated neutrophils may reduce concentrations of antioxidant vitamins and enzymes in plasma and red blood cells (RBC). Vitamin E is an important fat soluble antioxidant and its role on antioxidant parameters of BD is unclear. The study was undertaken to evaluate the role of vitamin E on lipid peroxidation (MDA) levels, antioxidant vitamin and enzyme concentrations in plasma and RBC in patients with BD. There were three groups i.e., control, patient and treatment groups with twenty-five subjects in each. Nonsmoking patients with BD, patient group, was compared with an equal number of healthy control subjects (control group). Blood samples were taken from both control and patient groups and then oral vitamin E was daily supplemented to the patients with BD for six weeks (treated group). At the end of six weeks, blood was taken from the treated group once more.RBC and plasma MDA levels, serum neopterin, complement system (C₃ and C₄), ASO, CRP, rheumatoid factor, plasma lipoprotein (a), total cholesterol concentrations and erythrocyte sedimentation rate were higher in the patient group than in the control group, but they were lower in the treatment group than in the patient group. While vitamins A, E and β-carotene concentrations in plasma, catalase, glutathione peroxidase activities and reduced glutathione levels in RBC and plasma were lower in patient group than in the controls, they were found to be higher in the treatment group than in the patient group.These results provide some evidence for a potential role of increased lipid peroxidation and decreased enzymatic and non enzymatic antioxidants in BD by its inflammatory character and vitamin E which may strengthen the antioxidant defense system, and may contribute to the treatment of BD.     

Measurement of erythrocyte lipids,lipid peroxidation,antioxidants and osmotic fragility in cervical cancer patients

BACKGROUND: Our aim was to examine the structural integrity of red blood cells in cervical cancer patients by measuring the concentrations of thiobarbituric acid reactive substances (TBARS), antioxidant status, cholesterol/phospholipid (C/P) molar ratio, enzyme activity and osmotic fragility of erythrocytes. METHODS: This study has been conducted on 32 adult female cervical cancer patients and an equal number of age- and sex-matched normal subjects. Erythrocyte concentrations of lipids, TBARS, vitamin E, reduced glutathione and enzymic activities of catalase and Na(+)K(+)-ATPase were measured as well as plasma concentrations of sodium and potassium. The present study also examined the changes in erythrocyte osmotic fragility in cervical cancer patients and normal subjects. The red cell fluidity and permeability were determined by estimating the C/P ratio and Na(+)K(+)-ATPase activity, respectively. RESULTS: The release of thiobarbituric acid reactive substances was significantly higher in cervical cancer patients as compared to normal subjects. The increased lipid peroxidation with concomitant decrease in antioxidants was notable in cervical cancer patients. Red blood cells of cervical cancer patients were more fragile than those from normal subjects. Increase in red cell membrane C/P ratio and Na(+)K(+)-ATPase activity was noticed in cervical cancer patients as compared to normal subjects. CONCLUSIONS: Increased lipid peroxidation, insufficient antioxidant potential and changes in C/P molar ratio as well as activity of Na(+)K(+)-ATPase cause structural and functional abnormalities in the erythrocytes of cervical cancer patients.     

Evidence of oxidative stress in the circulation of ovarian cancer patients

BACKGROUND: Ovarian cancer is the leading cause of death due to gynecological malignancies among women. The extent of free radical induced oxidative stress can be exacerbated by the decreased efficiency of antioxidant mechanisms. The present study was conducted to investigate the extent of oxidative stress and the levels of antioxidants in the circulation of ovarian cancer patients. METHODS: Plasma thiobarbituric acid reactive substances (TBARS) and conjugated dienes (CD) and the levels of antioxidants such as superoxide dismutase (SOD), catalase (CAT), vitamin C and vitamin E were estimated in the circulation of 30 ovarian cancer patients and an equal number of age-matched normal subjects as control. RESULTS: Significantly increased concentrations of plasma TBARS and CD and significantly lowered levels of SOD, CAT, vitamin C and vitamin E were observed in ovarian cancer patients as compared with normal subjects. CONCLUSION: The low levels of SOD, CAT, vitamin C and vitamin E in the plasma of ovarian cancer patients may be due to their increased utilization to scavenge lipid peroxides as well as their sequestration by tumor cells. Increased levels of lipid peroxidation may be due to excessive oxidative stress caused by incessant ovulation or epithelial inflammation.     

Effect of leptin on peroxidation and antioxidant defense in ethanol-supplemented Mus musculus heart

The aim of the study was to evaluate the effect of exogenous mouse leptin on ethanol-induced cardiac toxicity in mice. Administering ethanol (6.32 g/kg body weight p.o.) to 4-week-old healthy mice for 45 days resulted in significantly elevated plasma levels of leptin, lactate dehydrogenase (LDH), cardiac lipid hydroperoxides (LOOH) and thiobarbituric acid reactive substances (TBARS) and significantly decreased cardiac superoxide dismutase, catalase, vitamin C, vitamin E, reduced glutathione and glutathione-dependent enzyme levels (glutathione peroxidase and glutathione S-transferase). Subsequent to the experimental induction of toxicity (i.e., after the initial period of 30 days) exogenous leptin was administered (230 microg/kg body weight i.p.) every alternate day for 15 days along with the daily dose of ethanol. Leptin administration to ethanol-treated mice significantly elevated the levels of plasma leptin, LDH and cardiac LOOH, TBARS, whereas the activity of antioxidant enzymes and the concentrations of vitamins C and E were further decreased significantly. These findings were consistent with our histological observations, confirming that leptin enhances cardiac toxicity in ethanol-supplemented mice.     

Evidence of oxidative and nitrosative stress in patients with cervical squamous cell carcinoma

BACKGROUND: We conducted a study to evaluate reactive oxygen species (ROS) and reactive nitrogen species (RNS) simultaneously together with the antioxidant status in patients with cervical carcinoma. METHODS: We measured lipid peroxidation product, including malondialdehye (MDA), nitric oxide (NO) products, including nitrite (NO(2)(-)), nitrate (NO(3)(-)) and total nitrite (TNO(2)(-)) and antioxidant enzymes in 45 patients with cervical cancer and compared them against 30 healthy controls. RESULTS: Plasma as well as erythrocyte MDA and plasma NO levels was higher (p<0.001) in cervical cancer as compared to healthy controls. Antioxidant enzymes, Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities, were decreased (p<0.001) whereas glutathione S-transferase (GST) activity was increased (p<0.001) in cervical cancer patients. Lipid peroxidation and NO products accumulation correlated significantly with a deranged antioxidant system. CONCLUSIONS: We demonstrated a possible involvement of both oxidative and nitrosative stress, as evidenced by increased lipid peroxidation and NO levels with altered antioxidant defense system in the pathogenesis of cervical cancer.     

Antioxidants and lipid peroxidation status in the blood of patients with psoriasis.

The aim of this research was to determine levels in blood of vitamin E, beta carotene, lipid peroxidation as malondialdehyde (MDA), reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) activity in patients with psoriasis. Studies were carried out on 34 patients with moderate and severe psoriases and healthy age-matched controls. Red blood cell (RBC) and plasma samples from healthy and patient subjects were taken. Levels of GSH and the activity of GSH-Px in both plasma and RBC samples were significantly (P<0.001) lower in patients with psoriasis than in controls, whereas beta carotene levels in plasma and MDA levels in RBC samples were significantly (P<0.01, P<0.001) higher in patients with psoriasis than in controls. However, vitamin E and MDA levels in plasma did not differ statistically. Although being far from conclusive, these results provide some evidence for a potential role of increased lipid peroxidation and decreased antioxidants in psoriasis.     

Biochemical changes in tumor tissues of oral cancer patients

OBJECTIVES: Our aim was to assess the oxidative stress in tumor tissues of oral cancer patients by measuring the levels of lipids, thiobarbituric acid reactive substances (TBARS) and antioxidants. DESIGN AND METHODS: This study has been conducted on oral tumor tissues of 48 adult male oral cancer patients with various clinical stages (stage II to stage IV; 16 of each) and normal tissues of an equal number of age and sex matched disease free healthy subjects. The levels of lipids, lipid peroxidation and antioxidants in buccal mucosa of healthy subjects and oral cancer patients were assayed using colorimetric methods, except for vitamin E (fluorometriy). RESULTS: Total cholesterol and esterified cholesterol were markedly increased whereas phospholipids and free fatty acids were significantly decreased in tumor tissues as compared to normal tissues. The decrease in TBARS levels and functional compromise of antioxidant defense mechanisms were observed in the tumor tissues as compared to normal subjects. CONCLUSIONS: The low availability of peroxidizable substrates and the enhanced antioxidant capacity in tumor tissues make them less susceptible to oxidative stress, conferring a selective growth advantage on tumor cells.     

Antioxidant potential of vitamins A, E and C in modulating oxidative stress in rat brain

Background: Stress is known to affect synaptic plasticity, dendritic morphology and induces neurotoxic damage in humans, probably through generation of free radicals. Both ex vivo antioxidant vitamins and in vivo free radical scavenging enzymes exist. In the present study, restraint stress induced pro-oxidant status of rat brain was evaluated in terms of measurement of glutathione (GSH), lipid peroxidation (thiobarbituric acid reactive substances, TBARS) and free radical scavenging enzymes activities. The efficacy of antioxidant vitamins A, E and C alone and in combination was also evaluated in modulating inherent antioxidant system in stressed rats. Methods: Rats were treated with vit A, E and C alone (15 mg/kg of body weight) and in combination vitamins (E and C) prior to and after 6 h of restraint stress exposure. Both nonstressed and stressed rats were handled simultaneously. Pro-oxidant status of brain tissue was evaluated by determining the levels of GSH, TBARS and activities of superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT). Results: Restraint stress induced a decrease in the level of GSH and the activities of SOD, GST and catalase, while the levels of TBARS were found elevated. Both pre-stress and post-stress vitamin treatments (either alone or combined) resulted in alteration of these parameters towards their controls values with a relative dominance by latter. Vitamin E was found most effective in restoring inherent antioxidant system, no additive effect was observed in combined vitamin treatment as expected. Conclusion: Immobilization of rats generated oxidative stress in rat brain, by decreasing the activities of SOD, GST, catalase and glutathione levels, while increasing the lipid peroxidation. Post stress vitamin E treatment was found most effective than vitamins A and C in enhancing the levels of glutathione and activities of SOD, GST and catalase and decreasing lipid peroxidation. Thus vitamin E can be given as a nutritional supplement for scavenging free radical generated in the brain tissues in order to reduce oxidative stress.     

Involvement of oxidative stress in the pre-malignant and malignant states of cervical cancer in women

OBJECTIVES: To evaluate the potential role of oxidative stress in the evolution of cervical cancer, including its pre-malignant states. DESIGN AND METHODS: Erythrocytes thiobarbituric acid reactive substances (TBARS) levels, plasma vitamin C and thiol content and total blood delta-ALA-D levels were estimated in 46 untreated cervical cancer and pre-malignant patients and in 46 age-sex-matched controls. RESULTS: Erythrocytes from patients, regardless of disease state, pre-malignant (low squamous intraepithelial lesion--LSIL and high squamous intraepithelial lesion--HSIL) or cancer, showed a significant 2-3 times increase in TBARS levels (P<0.01). Plasma vitamin C was lower in the carcinoma group (P<0.01). The reactivation index of delta-aminolevulinate dehydratase (delta-ALA-D) was higher in the patient group, when compared to control (P<0.01). CONCLUSION: LSIL, HSIL or cervical cancer can be associated with changes in 3 indicators of oxidative stress: increase in erythrocyte TBARS, ALA-D reactivation index and a decrease in vitamin C content, that may play an important role in carcinogenesis.     

Oxidative stress and male IGF-1, gonadotropin and related hormones in diabetic patients.

Elevation of glucose concentration in diabetes may induce generation of oxygen free radicals such as superoxide (O2*-) and hydroxyl (*OH). The aim of the present study was to investigate the effect of the oxidative stress on the activities of blood superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R) and aldose reductase, the levels of reduced glutathione (GSH), lipid peroxidation (thiobarbituric acid reactive substances; TBARS) and plasma levels of insulin-like growth factor-1 (IGF-1), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone in type 2 (non-insulin-dependent diabetes) patients and in healthy controls. Blood SOD, CAT, GSH-Px and GSSG-R were lower in type 2 diabetic patients compared with the the control group. Blood aldose reductase activity was elevated in patients with type 2 diabetes compared with the control group. GSH was decreased while TBARS concentration was increased in red blood cells (RBC) and leukocytes from the patients with type 2 diabetes mellitus in comparison to the control group. The mean values of plasma LH, FSH and testosterone were decreased, whereas the mean plasma IGF-1 concentration was increased in type 2 diabetes compared with controls. These findings support the hypothesis that hyperglycemia enhances the activity of the polyol pathway and impairs the antioxidant status, particularly glutathione redox cycle, resulting in poorer defense against oxidative stress. In addition, decreased circulating testosterone and gonadotropin levels may reflect the oxidative stress exerted by diabetes.     

Elevated lipid peroxidation and disturbed antioxidant enzyme activities in plasma and erythrocytes of patients with uterine cervicitis and myoma.

OBJECTIVES: We investigated whether oxidative stress is associated with human uterine cervicitis and uterine myoma. DESIGN AND METHODS: We measured lipid peroxidation and antioxidant enzymes in plasma and erythrocytes of cervicitis patients and myoma patients in comparison with matched controls. Thiobarbituric acid-reactive substances (TBARS), a measure of lipid peroxidation, were determined in plasma; glutathione peroxidase (GSHPx) and catalase in erythrocytes; and superoxide dismutase (SOD) in both plasma and erythrocytes. RESULTS: We showed that plasma TBARS were significantly higher (p < 0.05) in both cervicitis patients and myoma patients than in controls. Plasma TBARS were significantly (and negatively) correlated with plasma and erythrocyte T-SOD activities in cervicitis patients only. Plasma T-SOD activity was significantly lower in both groups of patients than in controls whereas erythrocyte T-SOD activity was only significantly lower in myoma patients. The lowered plasma T-SOD activity in the cervicitis patients was attributed to decreased Mn-SOD activity whereas the lowered plasma T-SOD activity in myoma patients was attributed to decreased activities of both Cu,Zn-SOD and Mn-SOD. Erythrocyte GSHPx activity was 14% higher (p < 0.05) in cervicitis patients and 11% lower (p > 0.05) in myoma patients than in controls; catalase activity was 10% higher (p > 0.05) in cervicitis patients and 13% lower (p > 0.05) in myoma patients than in controls. Neither erythrocyte GSHPx nor catalase activity was significantly correlated with plasma TBARS. CONCLUSIONS: The elevated lipid peroxidation and disturbed antioxidant enzyme activities demonstrate the potential of oxidative injury in patients with uterine cervicitis and myoma.