Lipid profile, oxidant-antioxidant status and glycoprotein components in hyperlipidemic patients with/without diabetes

BACKGROUND: Plasma lipoproteins are protected against oxidative modification by the antioxidant defense system. An imbalance in the antioxidant defense system seems to result from the accumulation of low density lipoprotein (or) very low density lipoprotein in the course of hyperlipidemia. METHODS: The lipid profile, glycoprotein components, glucose, total proteins, albumin, lipid peroxidation and antioxidant status of plasma and erythrocytes were investigated in hyperlipidemic patients and hyperlipidemic patients with diabetes on treatment with glibenclamide (or) glipizide along with normal subjects and compared. RESULTS: A significant increase was observed in the levels of total cholesterol (TC), VLDL-C, triglycerides (TG), lipid peroxidation, ceruloplasmin (CP), glycoprotein components and glucose in the hyperlipidemic patients with/without diabetes and the increase was more pronounced (except TC) in patients with diabetes. The activities of erythrocyte antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and plasma concentrations of vitamins C and E, and reduced glutathione (GSH) decreased in hyperlipidemic patients with/without diabetes. GPx, CAT, vitamin C and GSH levels exhibited a further decrease in hyperlipidemic patients with diabetes. CONCLUSION: An enhanced levels of VLDL-C, TC/HDL-C ratio, TG, lipid peroxidation, glycoprotein components, and decreased concentrations of total proteins (TPs) and albumin were observed in hyperlipidemic patients with diabetes while the decrease was more marked in GSH, vitamin C, CAT and GPx among antioxidants.     

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.     

Oxidative stress and antioxidants in patients with cardiogenic shock complicating acute myocardial infarction

BACKGROUND: Lipid peroxidation and derived oxidized products are being intensively investigated because of their potential to cause injury and because of their pathogenic role in several diseases. The view that an excess of lipid peroxidation products is present and is relevant in the pathogenesis of cardiogenic shock-induced damage has still not received definitive support. METHODS: To evaluate the extent of lipid peroxidation, the status of enzymatic and nonenzymatic antioxidants in patients with cardiogenic shock that complicate acute myocardial infarction (AMI) and to compare with normal subjects. RESULTS: Compared with normal subjects, cardiogenic shock patients had higher malondialdehyde, conjugated dienes and reduced activities of erythrocyte antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and lower concentrations of reduced glutathione (GSH) in erythrocyte and in plasma GSH, vitamin C, vitamin E and in beta-carotene. CONCLUSIONS: Cardiogenic shock is associated with greater than normal lipid peroxidation and with an imbalance in antioxidants' status. These results indicate that low activities of SOD, CAT, GPx and low concentrations of GSH, vitamin C, vitamin E and beta-carotene in the circulation of patients with cardiogenic shock complicating AMI may be due to increased utilization to scavenge lipid peroxides. Decrease in plasma concentrations of GSH, vitamin E and beta-carotene seems to be responsible for the elevation of lipid peroxidation in cardiogenic shock complicating AMI compared with MI.     

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.     

Modulation of blood pressure, lipid profiles and redox status in hypertensive patients taking different edible oils

BACKGROUND: Free oxygen radicals and insufficiency of antioxidants have been implicated in the pathogenesis of hypertension. We determined the effect of edible oils on blood pressure, lipid profiles and redox status in hypertensive patients given antihypertensive therapy (nifedipine-calcium channel blocker). METHODS: 530 patients medicated with nifedipine were divided into 3 groups (356 patients-sesame oil; 87 patients-sunflower oil; 47 patients-groundnut oil) and the control group (n=40) received only the drug, nifedipine. The respective oils were supplied to the patients and instructed to use as the only edible oil for 60 days, which comes to 35 g of oil/day/person. Blood pressure, lipid profiles [total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and triglycerides (TG)], lipid peroxidation [thiobarbituric acid reactive substances (TBARS)], enzymatic [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)] and nonenzymatic [(vitamin C, vitamin E, beta-carotene and reduced glutathione (GSH)] in blood were measured at baseline and after 60 days of oil substitution. RESULTS: Patients with nifedipine alone or with respective oils had significantly lowered blood pressure. TC, LDL-C and TG decreased while HDL-C elevated in sesame and sunflower oil groups. Increases of HDL-C and TG were noted in groundnut oil group. TBARS levels reduced in all the groups whereas the reduction was remarkable in sesame oil group. Activities of SOD elevated in the 3 oil groups whereas GPx and CAT increased only in sesame oil group. Levels of vitamin C, vitamin E, beta-carotene and GSH increased in sesame oil group whereas vitamin E and beta-carotene were elevated only in sunflower and groundnut oil groups. GSH increased in drug control group also. CONCLUSION: Among the 3 oils, sesame oil offers better protection over blood pressure, lipid profiles and lipid peroxidation and increases enzymatic and nonenzymatic antioxidants.     

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.     

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.     

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.     

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.     

Superoxide anion radical, lipid peroxides and antioxidant status in the blood of patients with breast cancer

BACKGROUND: Reactive oxygen species (ROS), including superoxide anion radical (O2(-)), plays an important role in carcinogenesis. The human body has developed different antioxidant systems to defend against free radical attacks. We investigated the changes of the antioxidant status in the blood of patients with breast cancer. METHODS: The O2(-) generation and the levels of malondialdehyde (MDA) were measured as an index of lipid peroxidation along with the examination of the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GRx), the levels of reduced glutathione (GSH), oxidized glutathione (GSSG), and vitamins A, C, and E. RESULTS: The results showed that the levels of O2(-) and MDA, and the activities of antioxidant enzymes in the blood of the patients with breast cancer were significantly higher than the controls. However, the levels of vitamin C, GSH, GSSG and ratio of GSH/GSSG in the blood of the patients with breast cancer were significantly decreased compared to control subjects. CONCLUSIONS: Oxidative stress may be involved in breast cancer. The increased activities of erythrocyte antioxidant enzymes may be a compensatory upregulation in response to the increased oxidative stress.     

Lipid peroxidation and resistance to oxidation in patients with type 2 diabetes mellitus

We investigated lipid peroxidation, resistance of plasma and red blood cells to oxidation, and antioxidant defense system in erythrocytes and sera in patients with type 2 diabetes mellitus. One group included newly diagnosed 20 patients and the other included 20 patients treated with oral antidiabetic agents (OAD). Twenty healthy subjects served as controls. Serum and red blood cell malondialdehyde (MDA), glutathione (GSH), resistance to oxidation, and plasma thiol (total -SH) levels were measured. In addition, glycated hemoglobin, serum fructosamine, uric acid, total protein, total cholesterol, triglyceride and glucose levels were determined. Although newly diagnosed patients had higher serum and erythrocyte MDA levels than those of controls, the highest levels of MDA were determined in patients treated with OAD. MDA levels after exposing to oxidation increased in OAD group more than in newly diagnosed patients. Total -SH and erythrocyte GSH levels of the both diabetic groups were lower than controls. These results show that serum and erythrocyte lipid peroxidation was increased in diabetic patients. The sera of the patients showed a decreased resistance against oxidation. We therefore suggest that the effect of increased free radicals may be prevented by antioxidant systems in early stages of type 2 diabetes but in advanced stages this relationship is impaired owing to decreased antioxidant activity. Decreased red blood cell GSH and serum total -SH levels may be due to a compensation mechanism of the antioxidants.     

Oxidative stress and antioxidant status in patients with alcoholic liver disease

BACKROUND: Alcoholic liver diseases (ALD) are very common in lower socio-economical strata due to heavy drinking habits and multiple nutritional deficiencies. Ethanol causes liver damage by many mechanisms. The generation of lipid peroxidation by free radicals has been proposed as a mechanism for ethanol induced hepatotoxicity. These free radicals are destroyed by anti-oxidants. Many anti-oxidants are present in the diet, e.g., vitamin E, vitamin C etc. However, poor nutrition or malabsorption leads to deficiency of these vitamins. This may impair the anti-oxidative defense leading to ethanol induced oxidative stress and then to liver damage. METHODS: Oxidative stress and antioxidant defense were assessed in patients with alcoholic liver disease. Serum malondialdehyde (MDA) concentrations were measured as an index of lipid peroxidation, i.e., oxidative stress; and serum vitamins E and C concentrations were measured as an index of antioxidant status. RESULTS: Serum MDA concentrations were increased with the increase in severity of the disease. Concentrations of serum vitamins E and C were decreased in patients with alcoholic liver disease as compared to controls. CONCLUSIONS: Our observations may be due to increased demands of the same or increased utilization.     

Oxidant-antioxidant status in patients with oral squamous cell carcinomas at different intraoral sites

OBJECTIVES: To compare the extent of lipid peroxidation and the status of antioxidants in tumor and venous blood of patients with oral squamous cell carcinoma (OSCC) at different intraoral sites. DESIGN AND METHODS: Twenty four patients with OSCC at different intraoral sites and an equal number of age- and sex-matched reference subjects were chosen for the study. The concentrations of lipid peroxides and reduced glutathione (GSH) and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were estimated in tissues and blood. RESULTS: Diminished lipid peroxidation in tumor tissue was accompanied by decreased activities of SOD and CAT with increase in GSH and GSH-dependent enzymes. In contrast, enhanced lipid peroxidation with decrease in antioxidants was observed in the venous blood of OSCC patients. CONCLUSION: No significant differences in lipid peroxidation and antioxidant levels were observed between patients with OSCC at different intraoral sites. However, our results revealed differences between the tumor and blood with respect to their susceptibility to lipid peroxidation and antioxidant status.     

Normodipin in correction of platelet rheology in hypertensive patients with metabolic syndrome

AIM: To determine a therapeutic effect of normodipin on intravascular platelet activity in patients with arterial hypertension (AH) and metabolic syndrome (MS). MATERIAL AND METHODS: Twenty patients received normodipin for one month in a dose 10 mg/day. The drug activity was assessed by dynamics of anthropometric indices, lipid spectrum of the blood, lipid peroxidation in plasma and platelets, antioxidant protection of blood liquid and platelets, intravascular platelet activity. The results were processed statistically. RESULTS: Normodipin in hypertensive patients with MS has a positive effect on peroxidation and platelet aggregation. Long-term normodipin administration promoted stabilization of the effect. CONCLUSION: To reduce body mass in hypertensive patients with MS it is necessary to combine normodipin administration with nonpharmacological medication.     

The effect of dietary treatment on erythrocyte lipid peroxidation, superoxide dismutase, glutathione peroxidase, and serum lipid peroxidation in patients with type 2 diabetes mellitus

Objectives: The aim of the present study was to investigate the effect of dietary treatment on serum and erythrocyte lipid peroxidation and erythrocyte antioxidative enzyme activity of patients with Type 2 diabetes.

Design and methods: A total of 30 patients with newly diagnosed as Type 2 diabetes were enrolled to the study. A total of 30 healthy subjects served as controls. Diabetic patients were given standard dietary treatment that was composed of 50% to 55% carbohydrate and 30% fat for 2 months. No diet was applied for controls. For both groups serum and erythrocyte lipid peroxidation and erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were obtained at first and at the end of 2 months.

Results: Diabetic patients had higher serum and erythrocyte lipid peroxidation than those of controls before dietary treatment(p < 0.05). However, there was no absolute differences in erythrocyte SOD and GSH-Px (p > 0.05). At the end of 2 months of dietary treatment, while diabetics had still higher glucose and erythrocyte lipid peroxidation than controls (p < 0.05), serum lipid peroxidation, erythrocyte SOD, and GSH-Px levels did not differ significantly from those of controls (p > 0.05). In diabetic patients, after 2 months of dietary treatment, whereas serum and erythrocyte lipid peroxidation decreased, erythrocyte SOD and GSH-Px activities showed significant increase (p < 0.05).

Conclusions: Our results showed significant alteration in serum and erythrocyte lipid peroxidation and erythrocyte antioxidant enzyme status of patients with Type 2 diabetes by dietary treatment. However, whether such alterations have clinical importance for diabetic patients needs further investigation.     

Lipid and protein oxidation and antioxidant status in patients with angiographically proven coronary artery disease

OBJECTIVES: We aimed to evaluate the association of lipid peroxidation, protein oxidation and antioxidant system, and to assess an association with the severity of the disease, in patients with and without coronary artery disease (CAD) documented by coronary angiography. DESIGN AND METHODS: The population included 208 patients, undergoing clinically indicated coronary angiography. While the subjects with normal coronary angiograms (n=54) were evaluated as controls, the patients with CAD (n=154) were divided into three categories according to the number of diseased coronaries; one-vessel (n=50), two-vessels (n=51) and three-vessels (n=53). Lipid parameters were determined by routine laboratory methods. Plasma malondialdehyde and vitamin E concentrations were determined with the high-performance liquid chromatography. Other oxidant and antioxidant parameters were studied spectrophotometrically. RESULTS: While plasma malondialdehyde levels, the susceptibilities of erythrocyte and apolipoprotein B containing lipoproteins to in vitro induced oxidative stress, serum protein carbonyls, low density lipoprotein-cholesterol, triglyceride, apolipoprotein B and lipoprotein (a) levels had significantly increased, high-density lipoprotein-cholesterol and apolipoprotein AI levels, erythrocyte glutathione peroxidase, glutathione reductase, glucose 6 phosphate dehydrogenase, serum catalase, paraoxonase and arylesterase activities, plasma vitamin E and C and carotenoid levels had significantly decreased. The odds ratios for one-, two-, and three-vessel disease increased across especially higher tertiles of concentrations for oxidation parameters and lower tertiles of concentrations for antioxidant parameters. CONCLUSIONS: According to the results, we suggest that increased lipid and protein oxidation products and decreased antioxidant enzymes and vitamins contribute to increased oxidative stress which in turn is related to the severity of the disease.     

Pongamia pinnata modulates the oxidant-antioxidant imbalance in ammonium chloride-induced hyperammonemic rats

The effect of Pongamia pinnata (an indigenous plant used in Ayurvedic Medicine in India) leaf extract (PPEt) on circulatory lipid peroxidation and antioxidant status was evaluated in ammonium chloride-induced hyperammonemic rats. Enhanced lipid peroxidation in the circulation of ammonium chloride-treated rats was accompanied by a significant decrease in the levels of vitamin A, vitamin C, vitamin E, reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). PPEt-administered rats experienced a significant reduction in lipid peroxidation with a simultaneous elevation in antioxidant levels. Our results indicate that PPEt modulates these changes by reversing the oxidant-antioxidant imbalance during ammonium chloride-induced hyperammonemia and this could be due to its (i) antihyperammonemic effect by means of detoxifying excess ammonia, urea and creatinine and (ii) antioxidant property. The exact mechanism has to be still investigated and isolation of active constituents is required.     

Serum vitamin E,lipid peroxide and glutathione peroxidase in patients with chronic pancreatitis

It has been reported that lipid peroxidation increases in patients with antioxidant deficiencies, such as vitamin E and glutathione peroxidase. The relationships between serum lipid peroxide and vitamin E on the one hand and glutathione peroxidase on the other were examined in 22 patients with chronic pancreatitis, often accompanied by malabsorption of fats and fat-soluble vitamins due to the impaired exocrine pancreatic function.Both serum vitamin E concentrations and glutathione peroxidase activities were depressed, especially in patients with chronic calcifying pancreatitis. On the other hand, serum lipid peroxide levels were elevated. A significant negative correlation was found between the serum lipid peroxide levels and vitamin E concentration.These findings suggest that an elevation of the serum lipid peroxide level may be due to the lack of an antioxidative defense mechanism, such as vitamin E, against lipid peroxide.     

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.     

Lipid peroxidation and antioxidant status in experimental diabetes.

Oxidative stress is currently suggested as a mechanism underlying diabetes. The present study was designed to evaluate the oxidative stress related parameters in streptozotocin-induced diabetes in rats using different complementary approaches: susceptibility to in vitro oxidation (lipid peroxidation induction in liver homogenate, red blood cells hemolysis), blood antioxidant status (total antioxidant capacity by two approaches), and plasma isoprostane measurement, a new marker of lipid peroxidation in vivo. We have shown that induced liver thiobarbituric acid reactive substances increased after 4 weeks of diabetes, in spite of increased liver vitamin E content. Red blood cells hemolysis was significantly delayed after 4 weeks of diabetes. Plasma antioxidant capacity (AOC) tended to increase after 4 weeks of diabetes and was correlated with plasma vitamin E levels. Total antioxidant activity (TAA) significantly decreased after 1 week and a significant correlation was observed with plasma albumin levels. Plasma isoprostane (8-epiprostaglandinF2alpha) concentrations were not modified significantly 1 week or 4 weeks after the induction of diabetes. Levels of vitamin E in the diet and changes in its distribution among the body seems to play an important role in the development of oxidative stress during diabetes and its consequences.