Total Antioxidant Status Concentrations Research Articles

Lipid peroxidation in the kidney of rats treated with V and/or Mg in drinking water

Spontaneous and stimulated lipid peroxidation (LPO) after vanadate and magnesium treatment was studied in kidney supernatants obtained from outbred 5-month-old, albino male Wistar rats. The 2-month-old animals daily received: group I (control), deionized water to drink; group II, water solution of sodium metavanadate, NaVO(3) (SMV, 0.125 mg V ml(-1)); group III, water solution of magnesium sulfate, MgSO(4) (MS, 0.06 mg Mg ml(-1)); and group IV, water solution of SMV-MS at the same concentrations as in groups II and III for V and Mg, respectively, over a 12-week period. FeSO(4), NaVO(3) and MgSO(4) were selected as agents that may modify LPO process in in vitro conditions. Spontaneous malondialdehyde (MDA) levels in kidney supernatants increased significantly in the rats in groups II and IV, compared with groups I and III; and they were also significantly higher in all the groups of rats compared with the liver supernatants. The total antioxidant status (TAS) in groups II and IV tended to be higher too. Vanadium concentration in the kidney of the rats in groups II and IV increased, whereas the kidney Mg content in groups II, III and IV decreased, compared with levels in the liver. As the two-way ANOVA indicated, the changes in the basal MDA level, TAS and Mg concentration in the liver of rats at combined V and Mg application only resulted from independent action of V. As far as the in vitro results are concerned, in the supernatants obtained from the rats in groups II and IV, a significant increase in MDA level was demonstrated in the presence of 30 microm of exogenous FeSO(4) as well as 30, 100, 200 and 400 microm NaVO(3) and 100, 200, 400, 600, 800 and 1000 microm MgSO(4), compared with groups I and III. The 600, 800 and 1000 microm of exogenous MgSO(4) also significantly elevated MDA production in the supernatants obtained from the rats in group III, compared with spontaneously formed MDA in the same supernatants. The three-way ANOVA showed that the changes in LPO induced by in vitro treatment of kidney supernatants with exogenous Fe or V or Mg (600, 800 and 1000 microm) were a consequence of independent action of those metals and they also resulted from the interactions between exogenous Fe (Fe(exog)) and endogenous V (V(end)) and between V(end) and exogenous V (V(exog)). In conclusion, V (as NaVO(3)) consumed by the rats with drinking water at a dose of 12.9 mg V kg(-1) b.w. per 24 h for 12 weeks increased the basal LPO and markedly enhanced TAS in the renal tissue. Its pro-oxidant potential was also found in in vitro conditions. The Mg dose (6 mg Mg kg(-1) b.w. per 24 h) ingested by the rats together with V (12.7 mg V kg(-1) b.w. per 24 h) neither reduced nor intensified the spontaneous LPO, compared with V-only intoxicated animals; however, the stimulating effect of Mg on LPO was revealed in in vitro conditions.

Oxidative stress and the effect of parasites on a carotenoid-based ornament

It has been drawn to our attention that Fig. 1A,C,D in J. Exp. Biol.213, 400-407 appears to show the same data as fig 1a,d,e in a paper published by (some of) the same authors in Journal of Evolutionary Biology (Mougeot et al., 2010). The authors wish to clarify the relationship between these two papers and rectify the lack of cross-referencing.Both papers focus on red grouse and are outputs from the same large-scale field manipulation undertaken in 2006. They represent two, very different, stand-alone studies addressing different conceptual issues. The central experimental manipulation of both papers is the drug treatment of birds. The authors felt it was necessary to include background data in each paper to give the reader confidence in the efficacy of the experimental treatment and to allow the reader to better understand and interpret the main results of the papers, which explore very different physiological mechanisms that influence ornamental colouration.For this reason, the treatment effects on parasite burden and comb colouration were presented in both papers, although a different index of comb redness was used [adjusted R-values (fig. 1e in J. Evol. Biol.) vs adjusted R/(G+B) values (Fig. 1C in J. Exp. Biol.)]. Both indices are accurate reflections of comb redness, gave similar results and have been used in previous studies in different contexts to characterize comb colour. Both papers also include the same data on levels of circulating carotenoids [Fig. 1D in J. Exp. Biol.; fig. 1d in J. Evol. Biol.]. The authors feel the inclusion of these data in both papers can be justified conceptually. In the J. Exp. Biol. paper, the trade-off between the use of carotenoids for colouring ornaments vs dealing with oxidative stress is central to the key question. In the J. Evol. Biol. paper, these data reinforce the argument that carotenoid levels and ornamental colouration covary with corticosterone levels.The reiteration of background data on parasite removal and carotenoid levels does not compromise the uniqueness of each paper. The papers were submitted to, and published by, the respective journals in parallel, and the absence of cross-referencing was an oversight on the part of the authors, who acknowledge that the figure legends should have cited the corresponding paper and that the different indices used for comb redness should have been clarified.Consequently, the text of Fig. 1 in the J. Exp. Biol. paper should have read:Fig. 1. Mean ± s.e.m. changes over time in (A) T. tenuis abundance (worms male−1) (reproduced from Mougeot et al., 2010); (B) comb area (mm2); (C) comb redness (adjusted R/(G+B)-value; see Materials and methods) (data from Mougeot et al., 2010); (D) plasma carotenoid concentration (mg ml−1) (reproduced from Mougeot et al., 2010); (E) plasma concentration of malondialdehyde (MDA; nmol ml−1) and (F) plasma TAS (total antioxidant status; mmol ml−1). White squares: control males; black squares: treated (dosed) males (purged of parasites). Numbers above error bars refer to sample size (number of males).The following reference should also have been included in the Reference list:Mougeot, F., Martinez-Padilla, J., Bortolotti, G. R., Webster, L. M. I. and Piertney, S. B. (2010). Physiological stress links parasites to carotenoid-based colour signals. J. Evol. Biol.23, 643-650.The authors apologise for any inconvenience caused.

Lipid peroxidation and antioxidant status in rat: effect of food restriction and wheel running

Using the activity-based anorexia model, the aim of this investigation was to explore antioxidant enzyme activity (catalase, superoxide dismutase), total antioxidant status (TAS), and alpha-tocopherol in blood, liver, and gastrocnemius muscle associated with the food restriction and voluntary wheel running during 8 days. In addition, lipid peroxidation was measured by measurements of malondialdehyde (MDA). Wistars rats (n = 56) were randomly assigned to one of four groups: an ad lib sedentary group, a control wheel activity group, a food restriction-induced hyperactivity group (1 h/day ad lib food, 23 h/day ad lib wheel access), and a food-restricted sedentary group. The animals were killed when the rats in the food-restricted group had lost 25% of their free feeding weight. Antioxidant enzyme activities and TAS in blood, liver, and gastrocnemius muscle were unaffected by voluntary wheel running. A wheel activity effect (P < 0.05) was obtained for the MDA concentrations in plasma, with lower concentrations in trained animals. Food restriction effects were obtained for antioxidant capacity in liver, as well as for CAT activity in the gastrocnemius muscle and plasma MDA concentrations with lower values in the restricted animals. On the other hand, the food-restricted rats showed higher plasma TAS concentrations (P < 0.05) and higher alpha-tocopherol concentrations in the liver (P < 0.05) when compared to animals fed ad libitum. Our results also showed that food restriction coupled to wheel running decreased antioxidant parameters in liver, and plasmatic MDA concentrations and increased TAS plasma concentrations when compared to the ad libitum sedentary situation.

Association between enzymatic and non-enzymatic antioxidant defense mechanism with apolipoprotein E genotypes in Alzheimer disease

Objective There are evidence suggesting that APOE-ɛ4 allele play an important role in the pathogenesis of Alzheimer's disease (AD) by reducing peripheral levels and activities of a broad spectrum of nonenzymatic and enzymatic antioxidants systems. However, the link between APOE genotype, oxidative stress, and AD has yet to be established. In this study we examined whether antioxidant defense mechanism exacerbates the risk of AD in individual carrying APOE-ɛ4 allele in a population from Tehran, Iran. Method We determined the enzymatic activities of the erythrocyte Cu–Zn superoxide dismutase (Cu–Zn SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and serum level of total antioxidant status(TAS) in various APOE genotypes in 91 patients with AD and 91 healthy subjects as control group (age and sex-matched). Result The results showed that the TAS level and the activities of enzymatic antioxidants CAT and GSH-Px were significantly lower and the SOD activity was significantly higher in AD patients compared to controls. The AD patients with APOE-ɛ4 allele genotype had significantly lower serum TAS concentration and lower erythrocytes GSH-Px and CAT activities ( p = 0.001) but significantly higher erythrocytes Cu–Zn SOD activity ( p = 0.001) than the non-APOE-ɛ4 carrier AD and the control group. In addition, the association observed between the factors involved in an antioxidant defense mechanism and APOE-ɛ4 allele in AD increased with age of the subjects. Conclusion These data indicate that the reduced serum level of TAS and activity of CAT, GSH-Px and increased SOD exacerbate the risk of AD in individuals carrying APOE-ɛ4 allele. The reduced antioxidants defense in APOE–ɛ4 allele carrier may contribute to beta-amyloidosis. This effect, however, is more pronounced in the AD patients older than 75 years of age. This suggests that a therapeutic modality should be considered for these subjects.

High Dosage of Ascorbic Acid and Alpha-Tocopherol Is Not Useful for Diminishing Oxidative Stress and DNA Damage in Healthy Elderly Adults

Aim: To determine the useful dosage of ascorbic acid and alpha-tocopherol against oxidative stress and DNA damage in the elderly. Methods: A double-blind controlled clinical assay carried out in a sample of 66 healthy subjects divided into three age-paired random groups with 22 subjects in each group. Group A received placebo and group B was administered 500 mg of ascorbic acid and 400 IU of alpha-tocopherol, whereas group C received 1,000 mg of ascorbic acid and 400 IU of alpha-tocopherol for a 6-month period. The following measurements were performed before and after the 6-month treatment period: thiobarbituric acid reactive substances (TBARS); total antioxidant status (TAS); superoxide dismutase (SOD), and glutation peroxidase (GPx) and DNA damage by comet assay. Results: After 6 months, group B subjects exhibited an increase in SOD and GPx enzyme levels; however, this was not statistically significant (p > 0.05). Likewise, TBARS and TAS concentrations remained unchanged (p > 0.05). In addition, in group C the decrease in TBARS and increase in SOD, GPx, and TAS were not statistically significant (p > 0.05). Similarly, average DNA migration showed no significant differences with high-dosage ascorbic acid and alpha-tocopherol. Conclusion: These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.

Effect of L-carnitine administration on the modulated rat brain protein concentration, acetylcholinesterase, Na+K+-ATPase and Mg2+-ATPase activities induced by forced swimming

Background:Forced exercise produces free radicals and L-carnitine (L-C) administration reduces oxidative stress.Aim:To investigate whether short (2 hours) or prolonged (3 hours) forced swimming could modulate total antioxidant status (TAS), protein...

The effect of consecutive days of exercise on markers of oxidative stress

We examined the influence of 3 consecutive days of high-intensity cycling on blood and urinary markers of oxidative stress. Eight highly-trained male cyclists (VO2 max 76 +/- 4 mL.kg-1.min-1; mean +/- SD) completed an interval session (9 exercise bouts lasting 30 s each, at 150% peak power output) on day 1, followed by 2 laboratory-simulated 30 km time trials on days 2 and 3. The cyclists also completed a submaximal exercise trial matched to the interval session for oxygen consumption. Blood was collected pre- and post-exercise for the determination of malondialdehyde (MDA), total antioxidant status (TAS), vitamin E, and the antioxidant enzyme activity of superoxide dismutase and glutathione peroxidase, while urine was collected for the determination of allantoin. There were significant increases in plasma MDA concentrations (p < 0.01), plasma TAS (p < 0.01), and urinary allantoin excretion (p < 0.01) following the high-intensity interval session on day 1, whereas plasma vitamin E concentration significantly decreased (p = 0.028). Post-exercise changes in plasma MDA (p = 0.036), TAS concentrations (p = 0.039), and urinary allantoin excretion (p = 0.031) were all significantly attenuated over the 3 consecutive days of exercise, whereas resting plasma TAS concentration was elevated. There were no significant changes in plasma MDA, TAS, or allantoin excretion following submaximal exercise and there were no significant changes in antioxidant enzyme activity over consecutive days of exercise or following submaximal exercise. Consecutive days of high-intensity exercise enhanced resting plasma TAS concentration and reduced the post-exercise increase in plasma MDA concentrations.

Effects of fasting and refeeding on the antioxidant system in cockerels and pullets

The effect of fasting and refeeding on total antioxidant status (TAS), glutathione peroxidase (GSH-Px) activity and concentration of some non-enzymatic antioxidant compounds was studied in cockerels and pullets. Blood was collected before and after 48-h fasting and 24 h after refeeding. In cockerels, fasting resulted in a significant decrease of TAS and uric acid concentration. After refeeding, the concentration of TAS remained significantly lower as compared to the control level. At the same time, blood plasma level of total lipids increased in comparison to the control and post-fasting values. In pullets, fasting resulted in a significant decrease of whole blood haemolysate GSH-Px activity and blood plasma concentrations of albumin and uric acid. Simultaneously, a significant increase in total lipids and cholesterol was obtained. In pullets, refeeding resulted in a further decrease of TAS to undetectable values, a significant decrease of blood plasma cholesterol, and a significant increase of GSH-Px in the whole blood haemolysate and in blood plasma uric acid content. The results indicate that fasting has a negative impact on the antioxidant defence system of the blood, which leads to a reduced resistance to oxidative stress in both cockerels and pullets. However, pullets seem to be more susceptible to fasting-provoked oxidative stress than cockerels.

Gamma-Glutamyltransferase Activity and Total Antioxidant Status in Serum and Platelets of Patients with Community-acquired Pneumonia

We undertook this study to analyze serum and platelet gamma-glutamyltransferase (GGT) activity and total antioxidant status (TAS) concentration during the course of pneumonia and to compare them between patients with normal platelet count and those who developed reactive thrombocytosis. Platelet count, GGT activity and TAS concentration in serum (S) and platelet (Plt) isolates were measured in 60 patients with community-acquired pneumonia (CAP) on admission and at discharge. At the end of treatment, platelet count increased significantly from the value recorded on admission. By the end of treatment, 42% of patients developed reactive thrombocytosis. Serum and platelet GGT activity was higher, whereas (S)TAS was significantly lower in CAP patients than in control subjects. On admission, (Plt)TAS was significantly higher in CAP patients as compared with control subjects; at discharge, (Plt)TAS was lower in comparison with either patient admission and control subjects. GGT activity and TAS concentration in serum and platelet isolate on admission did not differ significantly between patients with and without thrombocytosis. At discharge, (S)GGT activity showed no significant changes, whereas (Plt)GGT decreased significantly in patients with thrombocytosis as compared with those without thrombocytosis. In patients with thrombocytosis, (S)TAS concentration showed no significant difference, whereas (Plt)TAS concentration measured at discharge was significantly lower in patients with thrombocytosis as compared to those with normal platelet count. The pattern of changes in (Plt)GGT catalytic activity and TAS concentration might be indicative of a certain role of thrombocytosis during treatment in patients with CAP. Further investigations are necessary to clarify these changes.

Evaluation of oxidative stress in Insulin Dependent Diabetes Mellitus (IDDM) patients.

BackgroundFree radical mediated oxidative stress is mainly involved in the pathogenesis of diabetic complications. Proteins and lipids are among the prime targets for oxidative stress. In the present study, we evaluated the oxidative stress in chronic IDDM patients by estimating the lipid peroxidation, protein oxidation, and antioxidants status.Subjects and designA total of 35 (15 IDDM + 20 normal healthy) children were examined in the study and estimated the lipid peroxidation, protein oxidation, and antioxidants – vitamin A (β-carotene, retinol), vitamin C, vitamin E and enzymatic antioxidants and nitric oxide.ResultsA statistically significant higher values of protein carbonyl groups and MDA as lipid peroxides were observed in diabetic patients with slight reduction in the synthesis of nitric oxide. It is interesting to note that there was a decrease in the antioxidant levels with corresponding increased protein and lipid oxidation. On PAGE under native conditions, we observed decreased levels of proteins – albumin, transferrin, ceruloplasmin and heptoglobulins and variable GC globulin fractions in IDDM compared to normal healthy controls.ConclusionHyperglycemia induces the overproduction of oxygen free radicals and consequently increases the protein oxidation and lipid oxidation. A significance difference in the mean plasma concentration of total antioxidant status was observed in IDDM patients. The findings of the present study suggest that diabetes in an altered metabolic state of oxidation-reduction and that it is convenient to give therapeutic interventions with antioxidants.

The total antioxidant status in the brain after ethanol or 4-methylpyrazole administration to rats intoxicated with methanol

In the study, the potential interaction of methanol/ethanol and methanol/4-methylpyrazole within the scope of the total antioxidant status (TAS) in rat brain was investigated. The experiment was carried out on rats exposed to N 2O/O 2 mixture (1:1 v/v) which enable to obtain similar response of rat organism to methanol poisoning as that observed in humans. The rats were exposed to N 2O/O 2 mixture 4 h before the administration of methanol or saline. The exposure to N 2O/O 2 was continued throughout the experiment. Methanol was administered orally at a dose of 3.0 g/kg, then, after next 4 h ethanol (0.5 or 1 g/kg) or 4-methylpyrazole (4-MP) (15.0 or 50.0 mg/kg.) was administered by i.p. injection. TAS in rat brain homogenates was assayed spectrophotometrically at λ=600. The mean concentration of TAS in rats exposed to N 2O/O 2 mixture did not differ from that determined for control rats. A slight decrease in TAS concentration was found in all groups of rats intoxicated with methanol and ethanol or 4-MP and methanol alone. There was no interaction between methanol and 4-MP. However, a significant decrease in TAS concentration was observed in rats following the ingestion of methanol and than after the administration of 1.0 g/kg of ethanol in comparison to rats receiving methanol alone ( p<0.05). This phenomenon suggests an adverse interaction of methanol/ethanol within scope of the brain antioxidant status equilibrium.

Reliability of different blood indices to explore the oxidative stress in response to maximal cycling and static exercises

This study compares the changes in four blood markers of exercise-induced oxidative stress in response to exercise protocols commonly used to explore the global muscle performance at work (maximal incremental cycle) and endurance to fatigue of selected muscles (static handgrip and thumb adduction). Cycling and static exercises allow the muscle to work in aerobic and anaerobic conditions, respectively. Healthy adults performed an incremental cycling exercise until volitional exhaustion and, on separated days, executed infra-maximal static thumb adduction and handgrip until exhaustion. Exercise-induced oxidative stress was assessed by the increased plasma concentration of thiobarbituric acid reactive substances (TBARS), the consumption of plasma reduced ascorbic acid (RAA), and erythrocyte reduced glutathione (GSH) antioxidants, and the changes in the total antioxidant status (TAS) of plasma. Five minutes after the end of the incremental cycling exercise, we measured a peak increase in TBARS level, maximal consumption of GSH and RAA, and a modest but significant decrease in TAS concentration. In response to both static thumb adduction and handgrip, significant variations of TBARS, GSH and RAA occurred but we did not measure any significant change in TAS level throughout the 20-min recovery period of both exercise bouts. The present study shows that only the changes in TBARS, GSH and RAA explore both dynamic and static exercises. In addition, TAS measurement does not seem to represent a reliable and unique tool to explore exercise-induced oxidative stress, at least during isometric efforts that allow the muscle to work under anaerobic condition.

Comparison of reactive oxygen species concentration in seminal plasma and semen parameters in partners of pregnant and non-pregnant patients after IVF/ICSI

The aims of this study were (i) to determine and compare the concentration of reactive oxygen species (ROS) and total antioxidant status (TAS) in seminal plasma and sperm parameters of the male partners of patients undergoing IVF or intracytoplasmic sperm injection (ICSI) treatment and (ii) to establish the relationship between ROS and TAS concentrations and sperm quality and their effect on fertilization and pregnancy rate of patients who achieved a pregnancy and those who were unsuccessful. Twenty-six IVF and 22 ICSI patients were included in this study. The ROS concentration in seminal plasma and sperm concentration, vitality (eosin test), motility, morphology, membrane integrity (HOS test), maturity (chromomycin, CMA 3) and DNA fragmentation (TUNEL) results and their relationship to fertilization and pregnancy were analysed. ROS concentrations were similar regarding the seminal plasma of male partners of patients who achieved a pregnancy and those who were unsuccessful. The other semen parameters, concentration, motility, vitality, membrane and DNA integrity, were comparable in both groups. However, both groups demonstrated a negative correlation between ROS concentration and sperm vitality, membrane integrity and morphology. Moreover, an inverse correlation was found between TUNEL, vitality, and membrane integrity. In conclusion, ROS concentration in seminal plasma affects the quality of spermatozoa. A negative correlation between the ROS concentration in seminal plasma and fertilization rate in both IVF/ICSI programmes was shown.

Lack of association between oxidized LDL-cholesterol concentrations and haptoglobin phenotypes in healthy subjects

The haptoglobin (Hp) 2-2 phenotype has been known to have less antioxidative activity than Hp 1-1 and Hp 2-1. However, few have reported the relationship between oxidative stress and Hp phenotypes by using oxidized LDL. The relationship between Hp phenotypes and oxidative stress was therefore investigated in healthy adults. The serum Hp concentrations, albumin, uric acid, iron, L-ascorbic acid, total antioxidant status and oxidized LDL concentrations were measured and analysed in 200 healthy Korean men and women with Hp 2-1 and Hp 2-2 phenotypes. The serum concentrations of Hp were significantly higher in the Hp 2-1 compared with the Hp 2-2 phenotype. However, serum concentrations of total antioxidant status and oxidized LDL did not show any statistical differences in either sex. The L-ascorbic acid concentrations in serum showed lower values in the Hp 2-2 compared with the Hp 2-1 phenotype, for both sexes (P < 0.05). The concentration of L-ascorbic acid, the first line antioxidant, was lower in the Hp 2-2 than in the Hp 2-1 phenotype; this did not significantly affect the total antioxidant status, and there was no significant difference in oxidized LDL for either group in healthy adults.

The effect of Nigella sativa oil on gentamicin nephrotoxicity in rats.

The pathogenesis of gentamicin (GM) nephrotoxicity has been shown to involve the generation of oxygen free radicals, and several free radical scavengers have been shown to ameliorate the nephrotoxicity. The seeds and oil of Nigella sativa are reported to possess strong antioxidant properties and was effective against disease and chemically-induced hepatotoxicity and nephrotoxicity. Therefore, in the present work, we have tested whether oral treatment of rats with N. sativa oil (0.5, 1.0 or 2.0 ml/kg/day for 10 days) would ameliorate nephrotoxicity of GM (80 mg/kg/day given intramuscularly and concomitantly with the oil during the last 6 days of treatment). Nephrotoxicity was evaluated histopathologically with a light microscope and by measurement of concentrations of urea, creatinine and total antioxidant status (TAS) in plasma and reduced glutathione (GSH) and TAS in kidney cortex. The results indicated that GM treatment caused moderate proximal tubular damage, significantly increased the concentrations of creatinine and urea, and decreased that of TAS and GSH. Treatment with N. sativa oil produced a dose-dependent amelioration of the biochemical and histological indices of GM nephrotoxicity that was statistically significant at the two higher doses used. Compared to controls, treatments of rats with N. sativa did not cause any overt toxicity, and it increased GSH and TAS concentrations in renal cortex and enhanced growth. The results suggest that N. sativa may be useful in ameliorating signs of GM nephrotoxicity in rats, and pending further experimentation to determine safety and efficacy, may be useful clinically.

Comparison between Total Antioxidant Status (TAS), Reactive Oxygen Species (ROS) and DNA integrity of IVF and ICSI patients and their predictive value of IVF/ICSI outcome

Objective: The purposes of this study were (i) to determine and compare the ejaculate parameters of subfertile patients undergoing either IVF or ICSI treatment. (ii) to find out the correlation between TAS, ROS concentration in seminal plasma, DNA integrity of spermatozoa and IVF/ ICSI outcome. (iii) to determine the predictive value of TAS and ROS concentration in seminal plasma of IVF, ICSI outcome.

Total antioxidant status and coronary artery calcification in type 1 diabetes.

Type 1 diabetes is associated with a high risk of coronary heart disease (CHD), despite the absence of dyslipidemia. Oxidative modification may render LDLs more atherogenic. We aimed to assess antioxidant status in type 1 diabetes and its association with coronary artery calcification (CAC). Total antioxidant status (TAS) of serum was measured using the Trolox equivalent antioxidant capacity assay in 48 type 1 diabetic and 25 nondiabetic subjects. The presence of CAC was assessed in the diabetic subjects using electron beam computed tomography. TAS was reduced in type 1 diabetic subjects compared with nondiabetic subjects (Mann-Whitney U test, P < 0.0001). There were associations between TAS and HbA(1c) (r = -0.43; P = 0.0026) and duration of diabetes (r = -0.35; P = 0.0157). Significant CAC was considered present if the Agatston score was >10. The diabetic subjects with significant CAC were older (P < 0.0001); had longer duration of diabetes (P = 0.0002); were more likely to have high blood pressure (P = 0.040); had higher total cholesterol concentration (P = 0.039), serum creatinine concentration (P = 0.003), and urinary albumin-to-creatinine ratio (P = 0.022); and had lower serum TAS (P = 0.018) compared with those without significant calcification. In logistic regression with CAC as the dependent variable, TAS was entered as a predictor, and the effects on its predictive value of adding other explanatory variables in bivariate analyses were assessed. The power of TAS to predict CAC was independent of many of the traditional CHD risk factors. Whereas TAS as a predictor was no longer statistically significant when age or duration of diabetes were entered into the model, the odds ratio for a TAS concentration above the median value predicting significant CAC only increased from 0.19 to 0.26 and 0.32, respectively. TAS is reduced in type 1 diabetes and is associated with the presence of CAC.

Antioxidant Status and Insulin-Dependent Diabetes Mellitus(IDDM).

The aim of this study was to examine changes in primary and secondary antioxidant defense system in children with insulin-dependent diabetes mellitus (IDDM). A total of 59 children (age range: 3 months 15 years) living in Cairo, Egypt were recruited. Twenty-four of these subjects had type-I diabetes (IDDM); they were admitted at the Abo-Elrish Hospital, Cairo. Thirty-five healthy well-nourished children were recruited from the local community, and used as controls. The antioxidant status of the study population was determined by measuring copper-zinc superoxide dismutase (Cu-Zn SOD) in red blood cells, glutathione peroxidase (GPX) in whole blood, and total antioxidant status (TAS) as well as ceruloplasmin and albumin in plasma. In addition, the plasma levels of trace elements involving antioxidant activities, such as copper (Cu), zinc (Zn), selenium (Se), and iron (Fe) were determined, along with a select group of vitamins. The latter included ascorbic acid, α-tocopherol and retinol. Plasma levels Se, Zn, and Cu were significantly higher in diabetic patients than in control subjects, while the mean plasma levels of albumin, ceruloplasmin, vitamin E, and vitamin C as well as Cu-Zn SOD activity in red blood cells, were significantly lower in IDDM patients than in their non-diabetic counterparts. No significant differences in plasma concentrations of TAS, vitamin A. retinol binding protein (RBP), and Fe as well as whole blood GPX activity were observed between the diabetic patients and control subjects. The plasma glucose level was inversely correlated with SOD and GPX. Overall, children with IDDM and persistent hyperglycemia are characterized by a decreased antioxidant defense system compared with health controls.