Evaluation of the indices of retinol and alpha-tocopherol status in free-living elderly.

The relationship between plasma vitamins and lipids was determined in volunteers (N = 131; age = 73.1 +/- 6.1 y). The 24-hour food intake data and fasting plasma retinol and alpha-tocopherol (HPLC), cholesterol, and triglycerides were determined three times in one year; 30 and 37% of elderly subjects had retinol and tocopherol intakes below two-thirds RDA, respectively; 35% used vitamin supplements. Plasma levels were: retinol = 1.76 +/- 0.41 mumol/L and tocopherol = 22.61 +/- 0.68 mumol/L; cholesterol = 5.15 +/- 0.77 mmol/L; triglycerides = 1.63 +/- 0.87 mmol/L. Plasma vitamin levels were adjusted to average plasma cholesterol (5.6 mmol/L) and triglyceride (1.24 mmol/L). Diet plus supplemental tocopherol intake correlated with plasma tocopherol (p less than .003). Using plasma vitamin levels, retinol status was normal, whereas 70% had low tocopherol status. Ratio of plasma alpha-tocopherol to lipids indicated that only 1-2% had low tocopherol status, while that of lipid-adjusted alpha-tocopherol to plasma lipids showed that 12% had low status. The latter ratio may be a better index of status.     

Plasma concentrations of dietary and nondietary antioxidants are low in severe asthma.

Low antioxidant levels and oxidative stress due to airway inflammation may be important determinants of asthma severity. The objective of the present study was to determine whether lower antioxidant intake and plasma antioxidant concentrations are associated with more severe asthma. Dietary antioxidant intakes and asthma severity were assessed using questionnaires, and plasma concentrations of ascorbic acid, vitamin E, carotenoids, bilirubin, albumin, uric acid and total antioxidant status were measured in 53 mild-to-moderate and 28 severe asthmatic patients and in 43 nonasthmatic subjects. Vitamin C and carotene intakes were lower in males than females and were particularly low in males with severe asthma. Plasma ascorbic acid was lower in severe (31.9+/-3.6 microM) compared with mild-to-moderate asthmatic (52.3+/-2.6) or control subjects (52.7+/-2.9). Low plasma ascorbic acid (odds ratio (OR) 0.93; 95% confidence interval (CI) 0.9-0.97), bilirubin (OR 0.69; 95% CI 0.51-0.93) and increased plasma cholesterol (OR 1.98; 95% CI 1.05-3.73) were independently associated with severe asthma. Albumin was positively and cholesterol negatively correlated with lung function. Low plasma concentrations of specific antioxidants are associated with more severe asthma. Increased antioxidant intake may help reduce the burden of severe asthma, particularly in males.     

Oxidative stress and antioxidant status in type 1 diabetes mellitus

OBJECTIVES: To test the hypothesis that type 1 diabetes is associated with increased oxidative stress and/or antioxidant status by investigating concentrations of 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) in urine and plasma and malondialdehyde (MDA) in plasma as indicators of lipid peroxidation in vivo, and antioxidant status in diabetic subjects compared with healthy control subjects. DESIGN AND SUBJECTS: Thirty-eight subjects with type 1 diabetes mellitus and 41 healthy age- and sex-matched control subjects were included in the study. Blood and urine samples were obtained and analysed for 8-iso-PGF2alpha with a newly developed radioimmunoassay, as well as for MDA, total antioxidant capacity (TAOC) and serum tocopherol levels. RESULTS: None of the variables of lipid peroxidation showed any significant difference between the two groups. Similarly, there were no significant correlations between the levels of 8-iso-PGF2alpha or MDA, and degree of glycemic control (HbA1c). Total antioxidant capacity in plasma was 16% lower amongst the subjects with type 1 diabetes than in the control group (P < 0.0005). Lipid corrected levels of alpha-tocopherol in serum were significantly increased in type 1 diabetic subjects (P < 0.05), as were gamma-tocopherol levels (P < 0.005). CONCLUSIONS: In spite of lower total antioxidant defence, our results do not support the oxidative stress hypothesis for type 1 diabetes mellitus. The higher tocopherol levels suggest that no vitamin E supplementation is necessary for subjects with type 1 diabetes mellitus.     

Low serum levels of carotenoids in sickle cell anemia

Serum carotenoids, tocopherols and retinol were analyzed in patients with sickle cell anemia (SCA) and in control subjects. The data show the following: the serum levels of the major carotenoids, alpha and beta carotene, cryptoxanthin, lycopene lutein, alpha tocopherol and retinol were significantly lower in SCA patients. These findings reflect an additional abnormality of the antioxidant system in SCA patients. Gamma tocopherol, on the other hand, was significantly elevated, consistent with the previously reported reciprocal relationship between serum alpha and gamma tocopherols. Thus, these data taken together with the earlier findings on the lower levels of plasma alpha tocopherol and ascorbic acid suggest that the entire antioxidant system may be compromised in SCA patients. This may contribute in part to the phenotypic expression of the condition.     

Serum antioxidant concentrations among U.S. adults with self-reported asthma.

Antioxidants may protect the lungs of people with asthma against oxidative stress. Among participants aged > or = 20 years from the Third National Health and Nutrition Examination Survey (1988-1994), we examined serum antioxidant concentrations of 771 persons with current asthma, 352 persons with former asthma, and 15,418 persons without asthma. After adjustment for age, participants with current asthma had similar mean concentrations of vitamin A, retinyl esters, vitamin C, vitamin E, vitamin E/cholesterol ratio, vitamin E/triglyceride ratio, alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, and selenium as participants without asthma. We repeated these analyses among participants who did not use vitamin or mineral supplements. After age adjustment, participants with current asthma had lower vitamin C and beta-cryptoxanthin concentrations and a lower mean vitamin E/triglyceride ratio than participants without asthma. In multiple linear regression models that included age, sex, race or ethnicity, education, smoking status, nonhigh-density lipoprotein cholesterol concentration, high-density lipoprotein cholesterol concentration, body mass index, physical activity, and alcohol use, asthma status was not significantly associated with any of the antioxidant concentrations. However, lower vitamin C concentrations were observed among people with current or former asthma than among people who never had asthma (p = 0.014). In the United States, people with asthma do not have manifest antioxidant deficiencies.     

The antioxidative defense in asthma.

Asthma is a disease characterized by chronic airway inflammation. Generation of oxygen free radicals by activated inflammatory cells produces many of the pathophysiologic changes associated with asthma and may contribute to its pathogenesis. However, the activities of antioxidant enzymes and their relation with asthma have not been well defined. This study was performed to examine the activities of major intracellular antioxidants in mild asthmatic patients. Twelve asymptomatic mild asthmatic patients who never used any antiasthma medication and 13 age- and sex-matched healthy control subjects were selected. The activities of erythrocyte antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), and glutathione-peroxidase (GSH-Px) were measured spectrophotometrically. The mean SOD activity of asthmatic patients was found to be significantly lower than that of the controls (p < 0.05). There was no significant difference in CAT and GSH-Px activities between patients and controls (p > 0.05). Although the mechanisms underlying the association between asthma and antioxidant system are unclear, according to our findings, decreased antioxidant protection may contribute to the pathogenesis of mild asthma.     

Effects of apple consumption on plasma and erythrocyte antioxidant parameters in elderly subjects

The effects of apple consumption on plasma and erythrocyte antioxidant parameters of elderly subjects were investigated in this study. Fifteen elderly subjects (mean age 71.86 +/- 4.17) participated in the study. They consumed an apple a day for 1 month. Before and after this period, fasting blood samples were obtained, and oxidant (malondialdehyde [MDA]) and antioxidant (superoxide dismutase [SOD], glutathione peroxidase [GSH-Px], catalase [CAT], and antioxidant potential [AOP]) parameters were studied. MDA and AOP levels were studied in plasma, and SOD, GSH-Px, and CAT activities and MDA levels were measured in the erythrocytes. In the erythrocytes, GSH-Px and SOD activities were found to be higher (p < .001 and p < .01), but MDA levels were lower in the second samples relative to the first ones. In the plasma, AOP value was found to be higher in the second samples relative to first ones (p < .001). No differences were found, however, between the routine blood parameters such as total cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, high-density-lipoprotein cholesterol, and triglyceride levels. The results show that consumption of apple leads to significant increases in the activities of some antioxidant enzymes and in the antioxidant potential values of the blood, and that decreases oxidation reactions in the body in significant amount. It is quite possible that reduced peroxidation processes owing to consumption of this fruit may play a part in some of their beneficial effects in the elderly subjects.     

Antioxidant liposoluble vitamins and carotenoids in chronic hepatitis

Background: It is known that antioxidant liposoluble vitamins and carotenoids are reduced in liver cirrhosis, but little is known about chronic viral hepatitis, where oxidative damage has to be taken into account. Methods: Fifty-five patients with chronic hepatitis, mainly C virus-related, were matched with 16 patients with biliary stones and 20 healthy controls. Plasma and liver analyses were carried out using a well-tried HPLC technique that affords an accurate quantification of retinol, tocopherol, alpha- and beta-carotene, cryptoxanthin, and lycopene. Results: Plasma concentration of retinol, tocopherol, beta-carotene, and lycopene was significantly decreased in both patient groups, particularly in those with chronic hepatitis. In contrast, liver concentration of both esterified and free retinol, tocopherol, and some carotenoids was better preserved in the hepatitis group than in the cholelithiasis group. A strict correspondence between aminotransferases and the amount of liver-stored retinol was documented. Conclusions: Plasma vitamin and carotenoid depletion co-existing with preserved liver storage may indicate a functional defect in liver pool mobilization or even a real depletion of the antioxidant defenses, which play a key role in averting cellular damage. The implications for nutrition and therapy need to be taken into account.     

Effects of Apple Consumption on Plasma and Erythrocyte Antioxidant Parameters in Elderly Subjects

The effects of apple consumption on plasma and erythrocyte antioxidant parameters of elderly subjects were investigated in this study. Fifteen elderly subjects (mean age 71.86 ± 4.17) participated in the study. They consumed an apple a day for 1 month. Before and after this period, fasting blood samples were obtained, and oxidant (malondialdehyde [MDA]) and antioxidant (superoxide dismutase [SOD], glutathione peroxidase [GSH-Px], catalase [CAT], and antioxidant potential [AOP]) parameters were studied. MDA and AOP levels were studied in plasma, and SOD, GSH-Px, and CAT activities and MDA levels were measured in the erythrocytes. In the erythrocytes, GSH-Px and SOD activities were found to be higher (p < .001 and p < .01), but MDA levels were lower in the second samples relative to the first ones. In the plasma, AOP value was found to be higher in the second samples relative to first ones (p < .001). No differences were found, however, between the routine blood parameters such as total cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein cholesterol, high-density-lipoprotein cholesterol, and triglyceride levels. The results show that consumption of apple leads to significant increases in the activities of some antioxidant enzymes and in the antioxidant potential values of the blood, and that decreases oxidation reactions in the body in significant amount. It is quite possible that reduced peroxidation processes owing to consumption of this fruit may play a part in some of their beneficial effects in the elderly subjects.     

Association of serum antioxidant capacity with coronary artery disease in middle-aged men

The possible involvement of oxidative damage in the progression of atherosclerosis has been suggested. There is some evidence that antioxidant therapy may be beneficial for the prevention of coronary heart disease. In this study, we investigated the relationship between coronary artery disease (CAD) and serum antioxidative status by measuring the total antioxidant status (TAS). Other relevant antioxidants, such as retinol, alpha, gamma-tocopherol, ascorbic acid, alpha, beta-carotenoids, erythrocyte glutathione peroxidase (GSH-Px) and oxidative products, were also determined in 31 male CAD patients with angiographically defined CAD and 66 male controls, aged 40-70 years, in a case-control study. The TAS levels, ratio and the concentrations of retinol, albumin, total protein and HDL cholesterol were significantly lower in the CAD patients than in the controls (p<0.01), and alpha-tocopherol and alpha/gamma-tocopherol were significantly higher in the CAD patients than in the controls. The TAS level correlated positively with gamma-GTP, GPT, GOT and uric acid (p<0.01). A multiple regression analysis in the CAD patients revealed that the TAS levels correlated most negatively with the number of diseased vessels. The concentrations of carotenoids and GSH-Px, as well as the alpha/gamma-tocopherol ratio were also significantly associated. Although conditional logistic regression analysis suggested low levels of HDL-cholesterol to be a significant coronary risk factor (OR=5.1, 95% CI=1.09-24.3), the TAS level showed no significant independent contribution to CAD. This study demonstrated an association of antioxidant parameters with the atherosclerosis progression, however, it did not confirm antioxidants as an independent risk factor for CAD event.     

Selenium, glutathione peroxidase and superoxide dismutase in maltese asthmatic patients: effect of glucocorticoid administration

Oxidative processes, mediated by free radical chemistry, are recognized to contribute significantly to the inflammatory pathology of bronchial asthma. This study analysed the degree of defence against reactive oxygen species in Maltese, asthmatic patients and in normal individuals, by measuring plasma selenium concentration, erythrocyte glutathione peroxidase (GSH-Px) activity and erythrocyte superoxide dismutase (SOD) activity, in order to determine their antioxidant status. The effect of glucocorticoids on the status of these antioxidants in patients was also investigated. The measurement of antioxidant status was carried out both in mild (n = 22) and severe (n = 37) asthmatics, as well as in healthy controls (n = 49). The same antioxidant profile was then investigated in a group of 16 severe asthmatics following treatment for 4 weeks with inhaled beclomethasone dipropionate (750 micrograms twice daily), and in a second group of 16 patients suffering from severe asthma, following 2-weeks treatment with oral prednisolone (15 mg daily during the first week and 10 mg daily during the second). No statistically significant difference was found in the plasma selenium concentrations and erythrocyte glutathione peroxidase activities between patients and controls. Both mild and severe asthmatics, however, exhibited a statistically significant lower erythrocyte superoxide dismutase activity than normal subjects (mild asthmatics: 62.9 (2.9) SOD 525 U/ml, severe asthmatics: 60.6 (1.9) SOD 525 U/ml, normal: 68.5 (1.1) SOD 525 U/ml, P < 0.01). Inhaled beclomethasone dipropionate exerted no effect on this antioxidant profile, while prednisolone caused a significant increase in plasma selenium concentration over pretreatment values (pretreatment: 118.3 (4.4) ng/ml, post-treatment: 138.1 (4.6 ng/ml, P < 0.01). It is thus suggested that asthmatic patients in Malta might be more susceptible to superoxide-induced damage than normal individuals. The reason for the prednisolone-induced augmentation of plasma selenium could not be determined from this study. It is postulated that the drug may decrease the excretion rate of the element, and may thus exert a positive antioxidant effect in individuals of established low selenium status.     

Relationship between serum antioxidant vitamins A, E, and C and lipid profiles in priest subjects at the Priest Hospital

The serum vitamins A, E, and C (antioxidant vitamins) of 112 priest subjects, compared with 90 males and 119 females in a control group, were investigated. Subjects for the study were Thai volunteers who attended the Outpatient Department, Priest Hospital, Bangkok, for a physical check-up from July to September 2003. There was no age difference between the priest group and the controls. All serum vitamins, A, E, and C, of the priest group were significantly lower than the control group. Statistically significantly higher levels of total cholesterol, LDL-C, and LDL-C/HDL-C ratio were found in the priest subjects compared with the controls. The median serum retinol concentration in the priest subjects was 3.02 micromol/l (range 1.47-4.01 micromol/l) compared with 3.23 micromol/l (range 1.74-4.57 micromol/l) in the controls (p<0.01). The median serum a-tocopherol concentration in the priest subjects was 18.1 mmol/l (range 5.8-27.3 micromol/l) compared with 19.6 mmol/l (range 7.3-37.7 micromol/l) in the controls (p<0.01). The median serum ascorbic acid concentration in the priest subjects was 3.74 mg/l (range 0.0-17.0 mg/l) compared with 6.37 mg/l (range 0.0-18.0 mg/l) in the controls. The median values for retinol, alpha-tocopherol, and ascorbic acid serum concentrations in the male priests were lower than the control males. A total of 28% and 65% of the priest subjects had decreased alpha-tocopherol and ascorbic acid levels, while the controls had decreased alpha-tocopherol and ascorbic acid levels of 20% and 31.5%, respectively. A total of 67.8% and 54.4% of priest and control subjects, respectively, had cholesterol concentrations of > or = 5.18 mmol/l. However, a prevalence of low HDL-C (HDL-C < or = 0.91 micromol/l) was found in 1.8% of priest subjects and 1.4% of controls. Statistically significant associations were found between alpha-tocopherol, cholesterol, LDL-C, triglyceride, and serum retinol. A positive correlation was found between age, retinol, and serum alpha-tocopherol. A negative correlation was found between cholesterol, HDL-C, LDL-C, and the serum alpha-tocopherol/cholesterol ratio. In addition, negative correlations were found between weight, cholesterol, LDL-C, triglyceride, and the serum alpha-tocopherol/(cholesterol + triglyceride) ratio in priest and control subjects. The results suggest more research should be conducted into the health and nutritional problems of both healthy and diseased priest subjects concerning vitamins and oxidative stress.     

Gamma, but not alpha, tocopherol levels in serum are reduced in coronary heart disease patients

Objectives. Low concentrations of alpha tocopherol are claimed to be associated with an increased prevalence of coronary heart disease. This study was undertaken to see whether measurements of serum tocopherol concentrations can contribute to discrimination between subjects with and without coronary heart disease.
Setting. All patients had been referred to the department of cardiology of the University Hospital in Uppsala, Sweden.
Subjects. Male patients ( n =69) below 60 years of age with coronary heart disease (CHD) and healthy age-matched reference subjects ( n =138) were compared.
Results. Lipid-corrected alpha tocopherol concentrations did not differ significantly between the groups, but the CHD group had a lower mean concentration of gamma tocopherol and a higher alpha/gamma ratio. In a stepwise logistic regression analysis, the LDL/HDL ratio was the best independent discriminator between the groups, followed by the proportion of palmitic acid in the cholesterol esters and the alpha/gamma tocopherol ratio.
Conclusions. The lower gamma tocopherol concentration and the high ratio between alpha and gamma tocopherol in the CHD group indicate a difference in antioxidative status between CHD patients and healthy subjects. The lipid-lowering treatment of these CHD patients is far from optimal.     

Erythrocyte antioxidant enzymes and blood pressure in relation to overweight and obese Thai in Bangkok

The specific activities of antioxidant enzymes, [eg superoxide dismutases (SOD), glutathione peroxidase (GPX) and catalase (CAT)], anthropometric measurements, including waist/hip ratio of 48 male and 167 female overweight persons (body mass index (BMI) > or = 25.0 kg/m2) compared with a 26 male and 80 female control group (BMI = 18.5-24.9 kg/m2) of Thai volunteers who attended the Out-patient Department, General Practice Section, Rajvithi Hospital, Bangkok, for a physical check-up during March-October, 1998, were investigated. There was a slightly significant difference between the median age of the sexes. The medians of height, weight, and waist/hip ratio in males were significantly higher than those in female overweight and obese subjects. The median of arm circumference (AC), mid arm muscle circumference (MAMC) in males was significantly higher than those in female overweight and obese subjects (p < 0.05). The prevalences of hypertension based on systolic and diastolic blood pressure of > or = 160/> or = 95 mmHg, were 8.3% and 37.5% for males and 5.4% and 18.6% for females, respectively. There was no significant difference between the median of antioxidant enzymes (SOD, GPX and CAT) between the sexes. No significant differences in the antioxidant enzymes in male overweight/obese persons and normal controls were presented, whereas antioxidant enzymes in female overweight/obese persons were statistically lower than in control females (p < 0.05). A significantly higher SOD, GPX, and CAT status was observed in normal subjects compared with overweight/obese subjects (p < 0.01). A higher prevalence of SOD < or = 2,866 U/gHb, GPX (< or = 15.96 U/gHb in females was found, compared with males. A high percentage of lower catalase (CAT < or = 19.2x10(4) IU/gHb) was found in both sexes (64.5% in males and 64.5% in females). In obese subjects (BMI > or = 30.0 kg/m2), there were significantly positive relationships between systolic and diastolic blood pressure, systolic blood pressure and waist/hip ratio, and SOD could be related to weight, BMI as well as GPX and CAT, whereas the opposite result was observed for age and SOD.     

Oxidant/antioxidant status in men with Behçet’s disease

Behçet’s disease (BD) is a chronic, progressive disorder that affects many systems of the body including the eye. The aim of this study was to assess whether the increase in oxidative stress in the affected tissues is reflected by lipid peroxidation and to check for alterations in antioxidants and antioxidant enzyme activities in patients with BD. Erythrocyte antioxidant potential (AOP), glutathione (GSH) and GSH-dependent enzymes (glutathione peroxidase (GSH-Px), glutathione reductase (GRD) and glutathione-S-transferase (GST), catalase (CAT), Cu–Zn superoxide dismutase (Cu–Zn SOD) activities, malondialdehyde (MDA) and some trace elements (zinc, Zn; copper, Cu; manganese, Mn) levels in men with BD. Erythrocyte CAT, GSH-Px activities, MDA, GSH, AOP and serum Zn values were significantly lower in patients with BD than in the control group. However, erythrocyte Cu–Zn SOD, GRD activities, erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP) and Cu values were significantly higher in patients with BD than in the control group, but GST activity and serum Mn values were unchanged. In conclusion, our results confirm the presence of oxidative stress in patients with BD and suggest that the severity of BD may arise from impaired antioxidant mechanisms. Therapy with antioxidants may lead to the increase in the antioxidant defense system and thus improvement in clinical symptoms.     

Hepatic oxidant/antioxidant status in cholesterol-fed rabbits: Effects of garlic extract

Aim:  The investigation of oxidant/antioxidant status in hepatic tissues from cholesterol-fed rabbits and the establishment of possible protective effects of aqueous garlic extract on cholesterol-induced hepatic steatosis.
Methods:  Twenty-two of 31 white New Zealand rabbits were given cholesterol (0.5 g/kg/day) for 4 months. Seven of them were then killed (cholesterol group). The remaining 15 animals were divided into two groups. Seven were fed on a normal laboratory diet (normal diet group) and the others (extract group) on a normal diet plus garlic extract (1.5 ml/kg/day) for an additional 3 months. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) enzyme activities, antioxidant potential (AOP) value, malondialdehyde (MDA), cholesterol and triglyceride levels in the liver tissues and total cholesterol and triglyceride levels in serum samples were measured. An histological evaluation was also done.
Results:  An impaired antioxidant system, reduced antioxidant defence potential and increased peroxidation were found in hepatic steatotic tissues from cholesterol-fed animals. Treatment with garlic extract caused a significant increase in antioxidant potential and partly eliminated peroxidation damage in the hepatic tissue. Additionally, the extract caused significant reductions in the cholesterol levels of blood and hepatic tissues. The histological evaluations were in accordance with these results.
Conclusion:  The results suggest that cholesterol-induced steatosis leads to a weakened antioxidant defence system and causes peroxidation in the hepatic tissue. Treatment with garlic extract may contribute to significant amelioration in the hepatic steatosis and peroxidation processes.     

The beneficial effects of physical exercise on antioxidant status in asthmatic children

BackgroundThe pathogenesis of asthma involves both airway inflammation and an oxidant/antioxidant imbalance. It is demonstrated in asthmatic adults that exercise programmes improve lung function, a mechanism yet to be elucidated. The purpose of this study was to investigate the possible beneficial effects of physical exercise on antioxidant status in asthmatic children which may lead to ameliorated lung function.MethodsThe study enrolled thirteen control and thirty asthmatic children. The asthmatic group was subdivided into two: the first group receiving only pharmacological treatment (n = 15) and the second receiving pharmacological treatment with exercise programme (n = 15) for 8 weeks. Blood samples were drawn from the subjects before and after treatment periods. As oxidant stress markers blood levels of malondialdehyde (MDA) and total nitric oxide (NO), and as antioxidant status, glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) enzyme activities were assessed.ResultsBefore any treatment was initiated, MDA and NO levels in the asthmatic group were significantly higher than the controls (3.40 ± 0.96 nmol/ml vs 2.46 ± 0.58 nmol/ml, and 12.53 ± 2.10 vs 9.40 ± 1.39 micromol/L, respectively). Both SOD (p = 0.0001) and GSH-Px (p = 0.023) activities were significantly lower in the asthmatic group. Pharmacological treatment and exercise programme together significantly improved lung performance and decreased the levels of oxidant stress markers, in concordance with a significantly increase in antioxidant enzyme activity measures when compared to the pharmacological treatment.ConclusionStructured exercise programme in asthmatic children resulted in better lung function, which may be attributed to its effect on antioxidant status.     

The in vivo antioxidant effectiveness of alpha-tocopherol in oxidative stress induced by sodium nitroprusside in rat red blood cells

Reactive oxygen species avidly reacts with nitric oxide (NO) producing cytotoxic reactive nitrogen species capable of nitrating proteins and damaging other molecules which leads to the reduction of erythrocyte deformability. The aim of this investigation was to assess the importance of alpha-tocopherol (Vit-E) in the total antioxidant status of the erythrocytes in sodium nitroprusside (SNP), a nitric oxide donor, induced oxidative stress and its relation to erythrocyte deformability. Male Swiss Albino rats were used in 4 groups, comprising of 10 animals in each group. The first group was the control, and the other groups were administered SNP (10 mg/kg, i.p.), Vit-E (10 mg/kg, i.p.) + SNP, and SNP + L-NAME (10 mg/kg, i.p.), respectively. Relative filtration rate (RFR), relative filtration time (RFT) and relative resistance (Rrel) were determined as the indexes of erythrocyte deformability. In addition, malondialdehyde (MDA, as an index of lipid peroxidation) and nitric oxide levels and the antioxidant activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) were also determined in the red blood cells of all groups revealing the oxidant-antioxidant activity. RFT and the Rrel of the erythrocytes of the SNP-treated rats increased significantly (p<0.05) whereas the RFR of the erythrocytes decreased (p<0.05) in comparison to all groups reflecting the impaired deformability. This reduction in RFR was prevented with both L-NAME or Vit-E incubation. Vit-E has also reduced the Rrel of the erythrocyte which reveals that it has improved the erythrocyte deformability. Lipid peroxidation was suppressed by Vit-E and L-NAME significantly, where the red blood cell deformability was improved. Furthermore, SOD and CAT activities were significantly stimulated with SNP treatment (p<0.05), where as GSH-Px remained unchanged. In the contrary, GSH-Px activity was triggered significantly by Vit-E administration, whereas the SOD and CAT activities were reduced (p<0.05). As a result, these data reveal that Vit-E improves the erythrocyte deformability in SNP-induced oxidative stress by its antioxidant effects on the lipid peroxidation and antioxidant enzyme activities.     

The effect of carnosine treatment on prooxidant–antioxidant balance in liver,heart and brain tissues of male aged rats

Carnosine (β-alanyl-l-histidine) is a dipeptide with antioxidant properties. Oxidative damage by free radicals is one of the mechanisms underlying the aging process. This study was done to investigate the effects of carnosine treatment on lipid peroxidation and antioxidant status of liver, heart, brain in male young and aged rats. At the initiation of study, young and aged rats were 5 and 22 months old, respectively. Carnosine (250 mg/kg, daily, i.p.) was administered for 1 month to rats. At the end of this period, malondialdehyde (MDA) and diene conjugate (DC) and protein carbonyl (PC) levels, glutathione (GSH), vitamin E and vitamin C levels and Cu,Zn-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione transferase (GST) activities were determined in tissues of carnosine-treated young and old rats. Liver and heart, but not brain MDA and DC levels increased significantly in aged rats as compared to young rats. Liver PC levels were also significantly elevated. Significant decreases in GSH and vitamin C levels and SOD activities were detected in liver of aged rats, but vitamin E levels and GSH-Px and GST activities remained unchanged. Non-enzymatic and enzymatic antioxidants did not change in heart and brain of aged rats. Carnosine treatment decreased high MDA, DC and PC levels and caused significant increases in vitamin E level and SOD activity in the liver of aged rats. There were no changes in non-enzymatic and enzymatic antioxidants in the heart and brain of carnosine-treated aged rats. In conclusion, carnosine treatment was found to be useful in the decrease of age-related oxidative stress in the liver.     

Evaluation of the Effect of Alcohol Consumption on Erythrocyte Lipids and Vitamins in a Healthy Population

There is epidemiological evidence that a moderate consumption of alcohol could reduce coronary heart disease. To corroborate this statement and to see how the consumption of red wine affects phospholipid and fatty acid patterns and antioxidant status, a survey was conducted on 58 adult males (20–75 years old). A questionnaire was used to discover their medical history, various constitutional and life-style factors, food habits, and nutrient intake; and the type and amount of alcoholic intake were investigated by means of a questionnaire. Subjects were divided into two groups of nondrinkers and average drinkers (mean 46.5 ± 4.4, range 30.2–63.4 g/day), and the effect of alcohol was made on the following variables: γ-glutamyltranspeptidase, apolipoprotein Al, apolipoprotein B, total and high-density lipoprotein-cholesterol, triglycerides, and antioxidant vitamins were determined in plasma; and phospholipids the fatty acids of phosphatidylcholine (PC) and phosphatidylethanolamine total cholesterol, α-tocopherol, β-carotene, and retinol were determined in red blood cells (RBCs). There were no significant differences between the two groups in protein, fat, carbohydrate, retinol equivalent, a-tocopherol content, and cholesterol/saturated fat index of their diet. Analysis of the plasma levels of biochemical variables–adjusted for age, smoking (number of cigarettes/day), and body mass index– showed a significant increase of γ-glutamyltranspeptidase and apolipoprotein Al concentration in the average drinkers compared with nondrinkers. Plasma α-tocopherol and retinol levels were also significantly higher in average drinkers. In the latter group, ANCOVA demonstrated a lower percentage of sphingomyelin in RBCs, with a lower sphingomyelin/PC ratio. This group also differs from the nondrinkers in RBC monounsaturated fatty acids (increased 18:1n9 and 16:1 n7 in PC) and polyunsaturated fatty acids (increase of 20:4n6 and 22:6n3 in phosphatidylethanolamine). These differences suggest that membrane fluidity may change in relation to alcohol intake.