A novel automated direct measurement method for total antioxidant capacity using a new generation, more stable ABTS radical cation

Antioxidant Activities of Eleven Australian Essential Oils

Essential oils are gaining increasing interest due to their multiple biological activities and great potential for therapeutic use. The antioxidant effect of essential oils is of special interest in diseases with inflammatory aspects. In this paper, the antioxidant activities of eleven essential oils extracted from Australian native plants were examined by the 2,2-diphenyl-1-picryhydrazyl (DPPH) and 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) assays. In the DPPH assay, all of the essential oils showed substantial antioxidant potential, with a radical-scavenging activity ranging from 12.9% ± 0.3% to 86.9% ± 0.2% at the concentration of 1.6 × 10−2 mL/mL. In the ABTS assay, lemon-scented tea-tree oil ( Leptospermum petersonii Bailey) (80.6% ± 0.7%), Australian blue cypress oil ( Callitris intratropica R. T. Baker & H. G. Smith) (78.6% ± 1.3%), lemon-scented eucalyptus oil ( Eucalyptus citriodora Hook.) (56.7% ± 0.9%) and lemon-scented ironbark oil ( Eucalyptus staigeriana F. Muell. ex Bailey) (58.9% ± 0.8%) exhibited relatively high radical-scavenging activities at the concentration of 1.6 × 10−2 mL/mL. Taken together, in both DPPH and ABTS assays, lemon-scented tea-tree oil (with IC50 of 1.5 × 10−3 mL/mL and 1.5 × 10−3 mL/mL, respectively), Australian blue cypress oil (with IC50 of 9.5 × 10−3 mL/mL and 3.0 × 10−3 mL/mL, respectively), lemon-scented eucalyptus oil (with IC50 of 4.8 × 10−3 mL/mL and 8.9 × 10−3 mL/mL, respectively) and lemon-scented ironbark oil (with IC50 of 6.4 × 10−3 mL/mL and 7.0 × 10−3 mL/mL, respectively) showed the highest antioxidant potential of the essential oils tested. By comparison, the antioxidant capacity of vitamin E had IC50 values of 5.3 × 10−5 mL/mL and 4.3 × 10−6 mL/mL in the DPPH and ABTS tests respectively.

Effect of adding extracted hesperetin, naringenin and pectin on egg cholesterol, serum traits and antioxidant activity in laying hens

In this study three feed additives (hesperetin, naringenin and pectin) for laying hens were investigated on their influence on the egg yolk cholesterol, serum traits and antioxidant activities in hens. Additives were extracted from citrus and grapefruit peels and contained 31.5% crude hesperetin, 39% crude naringenin and 60% galacturonic acid (pectin). Eighty 30-week-old Leghorn laying hens were randomly assigned to four groups and received, for two months, a control diet or diets with 0.05% hesperetin, 0.05% naringenin or 0.5% pectin. All additives reduced the egg yolk cholesterol level significantly. Feeding diets with added flavonoids (hesperetin and naringenin) increased the yolk weight and the ratio of yolk weight/egg weight and the blood serum superoxide dismutase (SOD) activity was elevated. Total antioxidation capacity, the level of thiobarbituric acid-reactive substances and superoxide scavenging capacity in the naringenin group were greater than in the control group. Supplemented flavonoids reduced the serum cholesterol level significantly, while serum triglyceride concentration in the naringenin and pectin groups was reduced. Addition of flavonoids resulted in an enhanced cholesterol level in excreta. The results of this study indicated that intake of hesperetin, naringenin and pectin extracted from citrus and grapefruit peel in laying hens diet, may exhibit positive effects.

Oxidative stress and male infertility--a clinical perspective

Oxidative stress occurs when the production of potentially destructive reactive oxygen species (ROS) exceeds the bodies own natural antioxidant defenses, resulting in cellular damage. Oxidative stress is a common pathology seen in approximately half of all infertile men. ROS, defined as including oxygen ions, free radicals and peroxides are generated by sperm and seminal leukocytes within semen and produce infertility by two key mechanisms. First, they damage the sperm membrane, decreasing sperm motility and its ability to fuse with the oocyte. Second, ROS can alter the sperm DNA, resulting in the passage of defective paternal DNA on to the conceptus. This review will provide an overview of oxidative biochemistry related to sperm health and will identify which men are most at risk of oxidative infertility. Finally, the review will outline methods available for diagnosing oxidative stress and the various treatments available.

Respiratory and cardiac manifestations of obstructive sleep apnea

Obstructive sleep apnea hypopnea syndrome (OSAHS) is largely under-diagnosed and unrecognized by primary care practitioners. Insidious changes within the respiratory and cardiovascular systems occur over time in untreated OSAHS. Respiratory manifestations of OSAHS include changes in the hypoxic ventilatory response, which can lead to long-term facilitation of ventilation in breathing and production of oxidative stress. Cardiovascular manifestations of OSAHS include increased sympathetic activity, endothelial dysfunction, and over-production of inflammatory cytokines. These changes are likely responsible for many of the pathologic sequelae associated with OSAHS.

Maternal active or passive smoking causes oxidative stress in cord blood

The aim of this study was to assess the influence of active and passive maternal smoking on cord blood total oxidant/antioxidant status at term. The levels of cord blood catalase (CAT), paraoxonase 1 (PON1), ceruloplasmin, total thiol and lipid hydroperoxide (LOOH), total antioxidant capacity (TAC), total oxidant status (TOS) and the oxidative stress index (OSI) were measured in samples of fetal cord blood serum from 29 nonsmokers who were not exposed to active or passive smoke, 30 passive smokers and 21 active smokers. The gestation period of all pregnancies was between 37 and 40 weeks, the pregnancies were uncomplicated and the infants were delivered vaginally. The weights of infants borne to the active smokers were significantly (P < 0.01) lower than those borne to the controls. Significantly lower concentrations of CAT, PON1 and TAC were found in the cord blood of the smokers than in that of the nonsmokers (P < 0.018). The cord blood levels of LOOH and TOS and OSI were significantly higher in the active and passive smokers than in the controls (P < 0.01). A significant positive correlation was found between maternal tobacco exposure and cord blood OSI (P < 0.001). Active or passive maternal smoking is associated with important alterations in the balance of oxidants and antioxidants in fetal cord blood and causes potent oxidative stress.

Do Dietary Antioxidants Alleviate the Cost of Immune Activation? An Experiment with Greenfinches

Reactive oxygen and nitrogen species produced by metabolism and immune defenses can cause extensive damage to biomolecules. To counteract this damage, organisms rely on exogenous and endogenous antioxidants, although their relative importance in maintaining redox balance is unclear. We supplemented captive greenfinches with dietary antioxidants--carotenoids and vitamin E--and injected them with an inflammatory agent, phytohemagglutinin. Compared to controls, immune-challenged birds circulated more lipid peroxidation products but also increased total plasma antioxidativity. Carotenoid (but not vitamin E) supplementation generally reduced lipid peroxidation, but this did not compensate for the effects of immune activation. Levels of an endogenous antioxidant--uric acid--strongly contributed to plasma antioxidativity. We found no evidence that dietary antioxidants are immunostimulatory. These results demonstrate the antioxidant function of carotenoids in birds and show that simultaneous assessment of oxidative stress-driven damage, antioxidant barrier, and individual antioxidants is critical for explaining the potential costs of immune system activation.

Sexual difference in ascorbic acid synthesis, tissue ascorbic acid and plasma total antioxidant capacity in mature chickens

1. An experiment was conducted with commercial White Leghorn type chickens to determine the effect of gender on tissue ascorbic acid concentration, antioxidant capacity and ascorbic acid synthesis. 2. Birds reared and maintained on litter were given a standard layer diet, without supplemental ascorbic acid, from 18 weeks of age. Tissue ascorbic acid concentration, plasma total antioxidant capacity and renal L-gulonolactone oxidase activity were measured at 30 weeks of age. 3. Females and males differed in ascorbic acid synthesis, as measured by renal L-gulonolactone oxidase activity, and tissue ascorbic acid concentration. 4. Plasma total antioxidant capacity and adrenal, gonadal, plasma and pituitary ascorbic acid concentrations were significantly higher in males, whereas ascorbic acid synthesis and splenic and thymic ascorbic acid concentrations were significantly higher in females. 5. L-Gulonolactone oxidase activity was not detected in the comb of cockerels.

Total oxidative/anti-oxidative status and relation to bone mineral density in osteoporosis

The aim of this study was to evaluate the total antioxidant status (TAS), total oxidative status (TOS) and oxidative stress index (OSI) in patients with postmenopausal osteoporosis. We also investigate the relation between bone mineral density and oxidative/antioxidative parameters. Thirty-nine patients with osteoporosis and 26 healthy controls were included in the study. Plasma TAS, TOS levels were determined by using a novel automated methods. Plasma TOS and OSI value were significantly higher, and plasma TAS level was lower in patients than in healthy controls (P < 0.001 for all). There was a significant negative correlation between OSI and BMD in lumbar and femoral neck region (r = -0.63, P < 0.001; r = 0.40, P = 0.018). The results of this study indicated that increased osteoclastic activity and decreased osteoblastic activity may be associated with an imbalance between oxidant and antioxidant status in postmenopausal osteoporosis. Therefore, supplementation of antioxidant-enriched diet to the therapy might shed light on the development of novel therapeutic strategies for osteoporosis.

Biochemical assessments of retinol, alpha-tocopherol, pyridoxal--5-phosphate oxidative stress index and total antioxidant status in adolescent professional basketball players and sedentary controls

Physical training is known to increase the antioxidant defence system and reduce exercise-induced oxidative stress. However, intense physical aerobic and anaerobic training with competition, such as those imposed on young professional basketball players can induce an increase of oxidative stress, which can be implicated with overtraining. The aim of this study was to test the effect of training and competition load on oxidative stress, antioxidant status, and vitamin levels in basketball players. Oxidative Stres Index (OSI 1), Total Peroxide (TPx) antioxidant (vitamin E, A and The total antioxidant status (TAC 1)), biochemical lipid parameters, as well as training results were measured. Results showed that all plasma vitamin levels were significantly higher in basketball players (vitamin A: 1.61 +/- 0.05 mmol/l, vitamin E: 26.45 +/- 0.72 mmol/l, vitamin B6: 10.58 +/- 0.7 mgr/l) than sedentary controls (vitamin A: 1.22 +/- 0.04 mmol /l, vitamin E: 19.24 +/- 0.73 mmol/l, vitamin B6: 6.0 +/- 0.35 mgr/l) (p < 0.01). In addition TAC 1 was 2.06 +/- 0.02 and 1.89 +/- 0.01 mmol Trolox eq/L in basketball players and controls, respectively (p < 0.01). Conversely OSI was 0.89 +/- 0.09 arbitrary unit and 0.88 +/- 0.071 arbitrary unit in basketball players and controls, respectively (p > 0.05). However, total plasma peroxide level (TPx) of basketball players and controls was not statistically different (18.55 +/- 2.07 and 17.18 +/- 1.61 micromol H2O2/L, respectively; p > 0.05). We conclude that physical exercise increase antioxidant levels and cause balance of the homeostasis. Training can not have positive or negative effects on oxidative stress depending on training load. The results suggested that oxidative stress and antioxidant measurement are significant in the biological follow-up of young basketball players.

Melatonin protects from ischemia/reperfusion-induced renal injury in rats: this effect is not mediated by proinflammatory cytokines

The pathophysiologic mechanisms leading to acute ischemic renal failure are not completely understood. Melatonin, a compound with well-known antioxidant properties, reduces IR-induced renal injury. The purpose of the present study was to investigate the changes in levels of tumor necrosis factor (TNF)-alpha, IL-beta, and IL-6 in postischemic reperfused renal tissue, and to determine whether the protective effect of melatonin is related the modulation of the production of these inflammatory molecules. Male Wistar albino rats were unilaterally nephrectomized and subjected to 1 hr of renal pedicle occlusion followed by 2 hr or 24 hr of reperfusion. Melatonin (10 mg/kg, i.p.) or vehicle was administrated at 10 min prior to ischemia. After 24 hr of the reperfusion, following decapitation, kidney samples were taken both for histologic examination and for the determination of malondialdehyde (MDA), myeloperoxidase (MPO) activity, total antioxidant capacity (TAC), total oxidative stress (TOS), creatinine, and blood urea nitrogen (BUN). These were measured in serum samples. TNF-alpha, IL-beta, and IL-6 were measured in kidney samples after 2 hr of reperfusion. IR caused a significant increase in renal MDA, MPO, TOS, creatinine, and BUN while decrease TAC without any change in TNF-alpha, IL-beta, and IL-6 levels. Melatonin treatment reduced the biochemical indices without any change in the cytokine levels and ameliorated histopathologic alterations induced by IR. The protective effect of melatonin on IR-induced renal injury is related to its antioxidant properties but not to proinflammatory cytokines.

The effect of resveratrol on prevention of the development of postoperative adhesions in a rat model

OBJECTIVE

Our aim was to investigate the anti-adhesion potential of resveratrol, a phytoestrogen naturally found in wine, in a rat uterine horn model.

METHODS

Lesions were created by laparotomy in the uterine horn of 70 rats, randomized before the operation into seven groups consisting of ten animals each: (1) control group, no adjuvant therapy; (2) intraperitoneal (IP) application of the resveratrol dilution vehicle, 10 mg/kg, before closing the laparotomy; (3) subcutaneous (SC) injection of dilution vehicle, 10 mg/kg, 30 min before the operation; (4) IP application of resveratrol, 10 mg/kg, before closing the laparotomy; (5) SC injection of resveratrol, 10 mg/kg, 30 min before the operation; (6) IP application of resveratrol, 10 mg/kg, before closing the laparotomy and continued SC daily for 5 days; and (7) SC injection of resveratrol, 10 mg/kg, 30 min before the operation and continued SC daily for 5 days. On the 14th postoperative day adhesion scores were determined. Levels of thiobarbituric acid-reactive substances and total antioxidant capacity (TAC) were also measured.

RESULTS

In animals treated with repeated SC resveratrol, adhesions were graded as significantly less severe than in the vehicle control group or the groups treated with resveratrol IP or IP plus SC. TAC of control group rats was significantly lower than that of animals treated with repeated SC resveratrol.

CONCLUSION

Repeated SC resveratrol significantly reduces adhesion formation.

Oxidant and antioxidant parameters in the treatment of meningitis

The aim of this study was to assess the effects of meningitis treatment on the serum and cerebrospinal-fluid oxidant and antioxidant status in children with bacterial meningitis. Forty children with bacterial meningitis, at ages ranging from 4 months to 12 years (mean age, 4 years), were enrolled in the study. Within 8 hours after admission (before treatment) and 10 days after clinical and laboratory indications of recovery (after treatment), cerebrospinal fluid and venous blood were collected. Thirty-seven healthy children (mean age, 4 years) were enrolled as control subjects, and only venous blood was collected. Serum total oxidant status, lipid hydroperoxide, oxidative stress index, uric acid, albumin, and ceruloplasmin levels were lower in the patient group after treatment (P<0.05). Serum total antioxidant capacity levels, vitamin C, total bilirubin, and catalase concentrations were not significantly altered by treatment (P>0.05). However, cerebrospinal fluid total oxidant status, lipid hydroperoxide, and oxidative stress index levels were higher, and cerebrospinal fluid total antioxidant capacity levels were lower after treatment than before treatment (P<0.05). In conclusion, we demonstrated that serum oxidative stress was lower, and cerebrospinal fluid oxidative stress was higher, after rather than before treatment in children with bacterial meningitis.

Effect of chronic oxidative/corticosterone-induced stress on ascorbic acid metabolism and total antioxidant capacity in chickens (Gallus gallus domesticus)

The consequences of chronic corticosterone-induced stress (CCIS) on ascorbic acid (AsA) metabolism in chickens, an animal that syntheses the vitamin, are not known. This study was conducted to determine whether CCIS alters AsA synthesis, as measured by l-gulonolactone oxidase (GLO) activity, tissue AsA, lipid peroxides and tissue total antioxidant capacity (TAC). Stress was induced by dietary administration of corticosterone from 2 to 4 weeks of age and measurements were made at 0, 7 and 14 days post-treatment. Ascorbic acid synthesis was not influenced by CCIS but hepatic, cardiac, renal, bursal and duodenal AsA concentrations were significantly decreased and plasma TAC and uric acid concentrations were significantly elevated. Stress caused significant hepatomegaly and hepatic lipidosis but hepatic peroxides were not elevated despite the slight decrease in hepatic TAC. Tissue TAC varied in different organs. It was markedly elevated in the kidney, reduced by 49% in the spleen, and changes were not detected in the heart and duodenum even though AsA concentration was significantly decreased in all tissues. We conclude that CCIS caused a significant reduction in tissue AsA concentration but did not inhibit GLO activity. The change in AsA concentration was associated with increase, decrease or no change in TAC in tissues examined. The findings suggest that CCIS may alter AsA recycling, influx or turnover in different tissues of chickens.

Paraoxonase, total antioxidant activity and peroxide levels in marasmic children: Relationships with leptin

OBJECTIVES

The aim of this study was to investigate the oxidant/antioxidant status, paraoxonase (PON) activity and leptin levels in children with marasmic malnutrition.

DESIGN AND METHODS

Thirty marasmic children (age 14.4+/-10.3 months) and 28 control subjects were included. Plasma PON activity, total antioxidant activity (TAO), total peroxide (TPX) and leptin levels were measured.

RESULTS

Malnourished children had significantly lower leptin (3.6+/-1.1 vs. 11.8+/-4.5 ng/mL, P<0.001), PON activity (66.4+/-28.6 vs. 221.3+/-31.6 IU/L, P<0.001) and TAO (1.44+/-0.12 vs. 2.45+/-0.61 mmol Trolox equiv/L, P<0.001); and higher TPX (15.6+/-6.4 vs. 5.9+/-1.9 micromol/L, P<0.001) values than in controls. Significant negative correlation was found between PON and TPX (P=0.040) and positive correlation between TAO and BMI (P=0.034) in patients. No significant correlation was found between leptin and oxidant/antioxidant parameters (P>0.05).

CONCLUSIONS

Children with marasmic malnutrition had increased pro-oxidant and decreased antioxidant status. Extent of oxidative stress increases with malnutrition severity. Antioxidants could be given during nutritional rehabilitation.

Serum oxidative-antioxidative status in patients with ankylosing spondilitis

Ankylosing spondylitis (AS) is an inflammatory disorder with unknown etiology that mainly affects the axial skeleton as well as the peripheral joints and extra-articular structures. The aim of this study was to evaluate the total antioxidant status (TAS), total oxidative status (TOS) and oxidative stress index (OSI) in patients with ankylosing spondylitis (AS). Fifty AS patients with a mean Bath AS Activity Index (BASDAI) 4.6 (range 4-9.3) and 26 healthy controls were included in the study. Plasma TAS, TOS levels were determined by using novel automated methods. The OSI was calculated. Plasma TOS level and OSI values were significantly higher, and plasma TAS level was lower in patients than in healthy controls (15.8 +/- 4. 9 vs. 4.3 +/- 2.8, 12.8 +/- 3. 9 vs. 9.6 +/- 5.5, 1.2 +/- 0.03 vs. 1.8 +/- 0.2, respectively, P < 0.001 for all). There was no significant correlation between oxidant/antioxidant parameters and disease activity. The results of this study indicated that increased oxidant and decreased antioxidant capacity may be associated with the pathogenesis of AS.

Oxidative stress is increased in critically ill patients according to antioxidant vitamins intake, independent of severity: a cohort study

Introduction

Critically ill patients suffer from oxidative stress caused by reactive oxygen species (ROS) and reactive nitrogen species (RNS). Although ROS/RNS are constantly produced under normal circumstances, critical illness can drastically increase their production. These patients have reduced plasma and intracellular levels of antioxidants and free electron scavengers or cofactors, and decreased activity of the enzymatic system involved in ROS detoxification. The pro-oxidant/antioxidant balance is of functional relevance during critical illness because it is involved in the pathogenesis of multiple organ failure. In this study the objective was to evaluate the relation between oxidative stress in critically ill patients and antioxidant vitamin intake and severity of illness.

Methods

Spectrophotometry was used to measure in plasma the total antioxidant capacity and levels of lipid peroxide, carbonyl group, total protein, bilirubin and uric acid at two time points: at intensive care unit (ICU) admission and on day seven. Daily diet records were kept and compliance with recommended dietary allowance (RDA) of antioxidant vitamins (A, C and E) was assessed.

Results

Between admission and day seven in the ICU, significant increases in lipid peroxide and carbonyl group were associated with decreased antioxidant capacity and greater deterioration in Sequential Organ Failure Assessment score. There was significantly greater worsening in oxidative stress parameters in patients who received antioxidant vitamins at below 66% of RDA than in those who received antioxidant vitamins at above 66% of RDA. An antioxidant vitamin intake from 66% to 100% of RDA reduced the risk for worsening oxidative stress by 94% (ods ratio 0.06, 95% confidence interval 0.010 to 0.39), regardless of change in severity of illness (Sequential Organ Failure Assessment score).

Conclusion

The critical condition of patients admitted to the ICU is associated with worsening oxidative stress. Intake of antioxidant vitamins below 66% of RDA and alteration in endogenous levels of substances with antioxidant capacity are related to redox imbalance in critical ill patients. Therefore, intake of antioxidant vitamins should be carefully monitored so that it is as close as possible to RDA.

Insight into the free-radical-scavenging mechanism of hydroxyl-substituent Schiff bases in the free-radical-induced hemolysis of erythrocytes

This work aimed to explore the mechanism by which hydroxyl-substituent Schiff bases scavenge free-radicals. Thus, four Schiff bases, that is benzylidene aniline (BAN), 2-(phenyliminomethyl)phenol (BAH), 4-benzimidoylphenol (PBH) and 2-benzimidoylphenol (OBH), were applied to protect human erythrocytes against 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH)-induced hemolysis. The results revealed that the --OH attached to the ortho-position of methylene in Schiff base scavenges 1.46 radicals per molecule, the --OH attached to the para-position of the N atom scavenges 2.94 radicals and the --OH attached to the ortho-position of the N atom scavenges 3.63 radicals. In addition, four Schiff bases were used together with some familiar antioxidants, such as 6-hydroxyl-2,5,7,8-tetramethyl chroman-2-carboxylic acid (Trolox), L-ascorbic acid (VC), alpha-tocopherol (TOH) and L-ascorbyl-6-laurate (VC-12) in AAPH-induced hemolysis of erythrocytes. It was found that, except for BAN+VC-12, BAH + VC-12, OBH + VC-12 and PBH+TOH, all the other combinations protected erythrocytes more perfectly than when used individually. This result demonstrated that a promotive protection existed between Schiff base and other antioxidants and this improved their ability to scavenge free-radicals. Finally, IC(50) values of the aforementioned Schiff bases together with 2-((o-hydroxylphenylimino) methyl)phenol (OSAP) and 2-((p-hydroxylphenylimino)methyl)phenol (PSAP) were determined by reaction with two radical species, that is, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical (ABTS(+.)) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH). The results implied that the molecular framework of a Schiff base and an --OH attached to the ortho-position of methylene were apt to reduce radicals, but the --OH attached to the aniline ring in a Schiff base was prone to scavenge radicals directly.

The effects of carbamazepine, valproic acid and phenobarbital on the oxidative and antioxidative balance in epileptic children

BACKGROUND

Oxidative stress has been related in a wide variety of ways with nervous tissue. We studied the effect of antiepileptic monotherapy on serum level of total antioxidant capacity, lipid hydroperoxide, total peroxide, oxidative stress index, and individual serum antioxidants such as albumin, bilirubin and uric acid.

PATIENTS AND METHODS

We studied 122 subjects including healthy controls, untreated epileptic patients and epileptic patients treated with valproic acid, carbamazepine or phenobarbital. Serum total antioxidant capacity was measured as an index of antioxidants, and total peroxide was measured as index of oxidative stress. The serum concentrations of uric acid, albumin, bilirubin and lipid hydroperoxide were monitored simultaneously.

RESULTS

We found that serum total antioxidant capacity levels were significantly decreased in the untreated group compared with the controls. Serum total peroxide levels were markedly increased in the untreated and carbamazepine-treated groups compared to in the controls; and lipid hydroperoxide and oxidative stress index levels were significantly higher in the phenobarbital-treated group than in the controls. Uric acid concentrations were significantly lower in the valproic-acid-treated group than in the untreated group, and total bilirubin concentrations were higher in the untreated group than in the controls.

CONCLUSION

Epileptic children exposed to oxidative stress and conventional antiepileptic drugs change the oxidative/antioxidative balance. The serum oxidant and antioxidant status of epileptic children with valproic acid monotherapy are better regulated compared with children with carbamazepine and phenobarbital monotherapy.

Total antioxidant/oxidant status in meningism and meningitis

The objective of this study was to investigate the antioxidant/oxidant status of serum and cerebrospinal fluid in children with meningismus and acute bacterial meningitis. Twenty-three children (age range, 0.75 to 9 years) with fever and meningeal signs that required analysis of the cerebrospinal fluid, but no cytologic or biochemical evidence of meningitis in their serum and cerebrospinal fluid, constituted the meningismus group. Thirty-one children (age range, 0.5 to 10 years) with acute bacterial meningitis constituted the meningitis group. Twenty-nine healthy children (age range, 0.5 to 11 years) were recruited as control subjects. Antioxidant status (ascorbic acid, albumin, thiol, uric acid, total bilirubin, total antioxidant capacity, catalase and ceruloplasmin concentrations) and oxidant status (lipid hydroperoxide and total oxidant status) were measured. The serum antioxidant status was lower, and oxidant status levels higher in both meningitis and meningismus subjects than in the control children (P < 0.001). Cerebrospinal fluid oxidant status was lower in the meningitis group than in the meningismus group (P < 0.05). These results indicate that serum antioxidant status was lower, and serum oxidant status was higher in children in the meningismus and meningitis groups, whereas cerebrospinal fluid oxidant status was higher in the meningismus group than in the meningitis group.

Increased DNA damage and oxidative stress in patients with rheumatoid arthritis

OBJECTIVES

Oxidative stress has been described as an important mechanism that underlies chronic inflammation in rheumatoid arthritis (RA). The aim of the study was to investigate the peripheral DNA damage, total antioxidant status (TAS), and total oxidative status (TOS) in patients with RA.

DESIGN AND METHODS

The study population contained 25 patients with RA and 26 healthy controls. DNA damage was assessed by alkaline comet assay in peripheral lymphocyte, plasma levels of total antioxidant status (TAS) and total oxidative status (TOS) were determined, and OSI was calculated using a novel automated measurement method. Disease activity was evaluated by DAS-28 score.

RESULTS

In RA patients, DNA damage was significantly higher than in controls (20.0+/-9.6 AU, 7.6+/-4.3 AU; p<0.001). Plasma TOS and OSI were higher in patients than in healthy controls (9.9+/-2.6 vs. 7.3+/-1.1, p<0.001; 1.04+/-0.4 vs. 0.7+/-0.1, p<0.001, respectively). Plasma TAS level in patients was lower than in healthy controls (0.9+/-0.7 vs. 1.01+/-0.7, p<0.001). DNA damage was correlated with TOS, OSI, and DAS-28 scores (r=0.682, p<0.001; r=0.753, p<0.001; r=0.519, p=0.008, respectively).

CONCLUSIONS

The findings indicated that lymphocyte DNA damage level increases in patients with RA. Elevated DNA damage may be related with increased oxidative stress and decreased antioxidant capacity. However, the mechanism of this association, and whether it is direct or indirect, remains to be explored.

Total antioxidant capacity and the severity of the pain in patients with fibromyalgia

The purpose of the study was to determine the oxidative and antioxidative status of plasma in patients with fibromyalgia. Total antioxidant capacity (TAC) of plasma was significantly lower in patients with fibromyalgia (n = 20) than in healthy controls (n = 20) [1.5 (SD 0.3) and 1.9 (SD 0.3) mmol Trolox equiv./l, P = 0.001]. In contrast, the total peroxide level of plasma was significantly higher in patients than in healthy controls [37.4 (SD 6.7) and 33.0 (SD 2.7) micromol H2O2/l; P = 0.01]. The oxidative stress index (OSI) level was significantly higher in patients with fibromyalgia than in healthy controls [2.5 (SD 1.0) and 1.8 (SD 0.4); P = 0.007]. A significant negative correlation between visual analogue scale (VAS) and TAC level was determined (r = -0.79, P < 0.001). The present results indicate that patients with fibromyalgia are exposed to oxidative stress and this increased oxidative stress may play a role in the etiopathogenesis of the disease. Supplementation of antioxidant vitamins such as vitamins C and E to the therapy may be indicated.

No increase in sperm DNA damage and seminal oxidative stress in patients with idiopathic infertility

The most common cause of male infertility is idiopathic. Standard investigations reveal no abnormality in such cases. The aim of the study was to investigate the levels of sperm DNA damage and seminal oxidative stress and their relationships with idiopathic infertility. The study included 30 normozoospermic infertile men seeking infertility treatment and 20 fertile donors. Semen analysis was performed according to the World Health Organization guidelines. Sperm DNA damage was assessed by alkaline single cell gel electrophoresis (comet assay) after preparation with two-step discontinuous Percoll gradient. Seminal oxidative stress was measured by a novel automated method. DNA damage score, total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) were not different in idiopathic infertile men compared with controls. No correlations were also found between DNA damage score and TAS, TOS levels and OSI in idiopathic infertile group. We did not find any relationship between sperm DNA damage and oxidative stress in normozoospermic infertile men. We think that the pathophysiology of idiopathic infertility cannot be explained by sperm DNA damage or seminal oxidative stress.

Oxidative and antioxidative status in the testes of rats with acute epididymitis

INTRODUCTION

Epididymitis is an inflammation or infection of the epididymis, a convoluted duct that lies on the posterior surface of the testicle. Oxidative stress due to excessive production of reactive oxygen species in epididymitis, impaired antioxidant defense mechanisms, or both, precipitates a range of pathologies that are currently believed to negatively affect the male reproductive function. How oxidative stress affects the testes is still unknown. We aimed to investigate the oxidative and antioxidative status of testes of rats with unilateral acute Escherichia coli epididymitis.

METHODS

The study included 36 male Wistar albino rats which were divided into three groups. In the epididymitis group (n = 12), an E. coli suspension was injected into the right ductus deferens of rats, and the same amount of saline was injected in the saline groups (n = 12). No surgery was performed in the control group (n = 12) for baseline values. Rats were sacrificed after 24 h and the epididymis and testes removed. The infection was confirmed by histopathologic evaluation and microbiological tests. The oxidative status of testes was evaluated by measuring myeloperoxidase (MPO) activity, and antioxidative status was evaluated by measuring total antioxidant response (TAR) and total antioxidant capacity levels (TAC).

RESULTS

MPO activity in both the ipsilateral and contralateral testes of the epididymitis group was significantly higher than those of the saline and control groups (p < 0.05). The TAR and TAC levels in both testes were also significantly elevated in the epididymitis group versus the two other groups (p < 0.05).

CONCLUSIONS

Acute epididymitis causes an increase of oxidative stress in the ipsilateral and contralateral testes, but this condition is strived for to tolerate the increase of endogenous antioxidants.

Oxidative and antioxidative capacity in children with cerebral palsy

The superiority of oxidative stress and/or the inadequacy of antioxidant capacity have an important role in disease. Decreased antioxidant availability has been observed in the pathogenesis of many different diseases affecting the brain, such as mitochondrial disorders, cerebral ischaemia and epilepsy. Oxidative and antioxidative status in children with cerebral palsy aged 1-12 years was investigated in this study and compared with healthy controls. Sixty-nine patients with cerebral palsy and 42 controls were enrolled in the study. Lipid peroxidation in the cerebral palsy group was significantly higher than that in the controls (7.54+/-3.64 micromol H(2)O(2)/L and 5.84+/-1.25 micromol H(2)O(2)/L, respectively) (P=0.02). Serum total antioxidant capacity levels were also markedly lower in the CP group than in the control group (1.42+/-0.22 mmol Trolox equiv./L and 1.64+/-0.17 mmol Trolox equiv./L, respectively) (P=0.003). Uric acid and albumin concentrations were lower in the study group than in the control group. Based on these results, we concluded that oxidants were increased and antioxidants were decreased in the cerebral palsy group, and, as a result, the oxidative/antioxidative balance shifted to the oxidative side in children with cerebral palsy.

Breast milk provides better antioxidant power than does formula

OBJECTIVE

We examined the effect of breast milk on plasma total antioxidant capacity (TAC), total peroxide (TP), and oxidative stress index (OSI), which are biomarkers of oxidative status.

METHODS

Fifty-four healthy term infants 3 to 6 mo of age were fed breast milk or a cow's milk modified formula. Plasma TAC, vitamin C, albumin, bilirubin, and uric acid levels were measured as indexes of antioxidative markers. Plasma TP levels were measured as an oxidative stress marker. The OSI was calculated to assess oxidative status.

RESULTS

No significant differences were observed between groups with respect to growth or anthropometric measurements. Plasma uric acid, total protein, and albumin concentrations were slightly higher in the breast-fed group than in the formula-fed group. There was a positive correlation between infant's age and serum albumin levels; between TAC and plasma uric acid, albumin, and total bilirubin; and between plasma iron and TP levels in both groups (r > 0.256, P < 0.05). In addition, there was a negative correlation between plasma iron and TAC (r = -0.267, P = 0.01). Plasma TAC and vitamin C levels were significantly higher in the breast-fed group than in the formula-fed group (P < 0.05). Plasma TP levels and the OSI were higher in the formula-fed group than those in the breast-fed group (P < 0.05).

CONCLUSIONS

Our data suggest that breast milk provides better antioxidant power than does formula.

Optimisation of the azinobis-3-ethyl-benzothiazoline-6-sulphonic acid radical scavenging assay for physiological studies of total antioxidant activity in woody plant germplasm

A robust spectroscopic method for determining total antioxidant activity in aqueous extractions has been applied to tissues from diverse woody plant species, including seeds of Coffea arabica and in vitro shoots from Ribes nigrum, Picea sitchensis and Shorea leprosula. The assay involves scavenging of an ABTS [2,2'-azinobis-(3-ethyl-benzothiazoline-6-sulphonic acid)] radical generated by the reaction of potassium persulphate with ABTS to produce an ABTS*(+) chromophore (lambda=734 nm). Antioxidants reduce ABTS*(+) back to ABTS with a concomitant decrease in absorbance. Aqueous extractions from C. arabica and S. leprosula had considerably higher (110-205 micromol Trolox eq. g(-1) FW) total antioxidant activities than P. sitchensis and R. nigrum (6-11 micromol Trolox eq. g(-1) FW). Further studies in two of these species showed that the inclusion of water-insoluble polyvinylpyrrolidone during aqueous tissue extraction enabled the combined phenolic and alkaloid antioxidant activity to be determined. These fractions accounted for 85% and 60% of total antioxidant activity for C. arabica seeds and R. nigrum shoots, respectively. The ABTS radical scavenging assay is presented herein as a robust method for determining total antioxidant activity in germplasm from diverse woody plant tissues and species. Its applicability to study oxidative stress in tissue cultures and germplasm employed in plant biotechnology, breeding and stress physiology programmes is discussed.

Estimate of antioxidant capacity and lipid peroxidation in plasma of healthy subjects

Serum contains various antioxidant molecules that may provide important protection against free radical attack. The aim of this work was to assess the total antioxidant capacity of plasma and a marker of lipid per oxidation [(thiobarbituric acid-reactive substances (TBARS)] in plasma of healthy smoking and non-smoking young and elderly subjects. In addition, we investigated plasma concentrations of α-tocopherol, β-carotene, and ascorbic acid. In in vitro experiments, the effects of exogenous compounds (ascorbic acid, uric acid, Trolox) on total ferric-reducing activity of plasma (FRAP) were also tested. We demonstrated that total antioxidant capacity of plasma obtained from healthy non-smoking young subjects was significantly higher than plasma antioxidant capacity of smoking elderly subjects. The concentration of TBARS in young non-smoking volunteers was lower than that in young smokers. The concentration of TBARS in elderly non-smoking volunteers was lower than in elderly smokers. Plasma concentrations of alpha-tocopherol, beta-carotene and ascorbic acid were significantly lower in elderly smoker than in elderly non-smokers of the same age. No difference in the plasma levels of alpha-tocopherol, beta-carotene and ascorbic acid were found in 22-year-old smoking and non-smoking subjects. In vitro addition of ascorbic acid, uric acid, or Trolox to plasma samples significantly increased their total antioxidant capacity. Decrease of FRAP values and increase of TBARS concentrations is a significant physiologic condition of the aging process. Supplementation of antioxidants could be useful for the enhancement of antioxidant screen in plasma.

Plasma oxidative stress biomarkers, nitric oxide and heat shock protein 70 in trained elite soccer players

The physiological response to the physical exercise involves a number of changes in the oxidative balance and in the metabolism of some important biological molecules, including nitric oxide (NO) and heat shock proteins (Hsp 70). With the aim to optimise previous laboratory diagnostic panels, we measured the plasma concentration of reactive oxygen metabolites (ROMs), total antioxidant status (TAS), glutathione reductase (GR) activity, and NO and Hsp 70 levels in 44 elite, antioxidant-supplemented and trained soccer players and in 15 sedentary controls. Although no statistically significant difference between athletes and controls was detected in the plasma level of ROMs and TAS, soccer players showed a significantly higher plasma GR activity, NO and Hst 70 levels than those of sedentary controls. These findings suggest that the measuring of relatively novel biomarkers in sport medicine, like GR, NO and Hsp 70, in addition to the well-known and reliable assays (d-ROMs test and TAS) may be useful to a clinician to better assess and evaluate the benefits of training and/or supplementation programs.

Decreased total antioxidant capacity and increased oxidative stress in passive smoker infants and their mothers

BACKGROUND

Smoking has many adverse health effects in infants and adults. The purpose of the study was to study the effect of passive cigarette smoking on oxidative and antioxidative status of plasma in passive smoker infants and their mothers and to compare with those of non-smokers.

METHODS

Subjects were randomly chosen from infants aged 8-26 weeks and their mothers aged 20-34 years. Passive smoker infants (n = 29) and their mothers (n = 29) were defined as having other family members who smoked six or more cigarettes per day continually for at least 8 weeks. Non-smokers were defined as infants (n = 30) and their mothers (n = 24) who had never been exposed to passive smoking. The antioxidative status of plasma were perused by measuring the total antioxidant capacity. Oxidative status was evaluated by predicating total peroxide level, oxidative stress index, protein oxidation and lipid peroxidation.

RESULTS

Plasma concentrations of total antioxidant capacity were significantly lower in passive smoker infants and their mothers than non-passive smoker infants and their mothers. However, lipid peroxidation and oxidative stress index were remarkably higher in passive smoker infants and their mothers than those of non-passive smoker infants and their mothers. There were significant correlations between the oxidative and antioxidative parameters of the passive smoker infants and their mothers.

CONCLUSIONS

Oxidants are increased and antioxidants are decreased in passive smoker infants and their mothers than those of non-smokers. Passive smoker infants and their mothers are exposed to potent oxidative stress.

Increased oxidative stress in infants exposed to passive smoking

The purpose of this study was to assess the effect of passive cigarette smoking on the oxidative and anti-oxidative status of plasma in infants. Eighty-four infants aged 6-28 weeks were divided into two groups: the study group included infants who had been exposed to passive smoking via at least five cigarettes per day for at least the past 6 weeks at home, while the control group included infants who had never been exposed to passive smoking. The antioxidative status of plasma was assessed by the measurement of individual antioxidant components: vitamin C, albumin, bilirubin, uric acid, thiol contents and total antioxidant capacity (TAC 1 and TAC 2). Oxidative status was assessed by the determination of total peroxide levels and the oxidative stress index (OSI 1 and OSI 2). Plasma vitamin C, thiol concentration and TAC 1 and TAC 2 levels were significantly lower, whereas plasma total peroxide levels and OSI 1 and OSI 2 were significantly higher, in passive smoking infants than in the controls (P<0.01). We conclude that passive smoking has a negative impact on numerous parts of the antioxidant defence system in infants, and exposes them to potent oxidative stress.