Oxidative stress is postulated to be responsible for the postprandial impairments in vascular function. The purpose of this study was to measure pulse wave velocity (PWV) and markers of postprandial oxidative stress before and after an acute bout of moderate exercise. Ten trained male subjects (age 21.5 +/- 2.5 years, VO2 max 58.5 +/- 7.1 ml kg(-1) min(-1)) participated in a randomised crossover design: (1) high-fat meal alone (2) high-fat meal followed 2 h later by a bout of 1 h moderate (60% max HR) exercise. PWV was examined at baseline, 1, 2, <em>3</em>, and 4 h postprandially. Blood Lipid hydroperoxides (LOOHs), Superoxide dismutase (<em>SOD</em>) and other biochemical markers were measured. PWV increased at 1 h (6.49 +/- 2.1 m s(-1)), 2 h (6.94 +/- 2.4 m s(-1)), <em>3</em> h (7.25 +/- 2.1 m s(-1)) and 4 h (7.41 +/- 2.5 m s(-1)) respectively, in the control trial (P < 0.05). There was no change in PWV at <em>3</em> h (5.<em>3</em>6 +/- 1.1 m s(-1)) or 4 h (5.95 +/- 2.<em>3</em> m s(-1)) post ingestion in the exercise trial (P>> 0.05). LOOH levels decreased at <em>3</em> h post ingestion in the exercise trial compared to levels at <em>3</em> h (P < 0.05) in the control trial. <em>SOD</em> levels were lower at <em>3</em> h post ingestion in the control trial compared to <em>3</em> h in the exercise trial (0.52 +/- 0.05 vs. 0.41 +/- 0.1 units mul(-1); P < 0.05). These findings suggest that a single session of aerobic exercise can ameliorate the postprandial impairments in arterial function by possibly reducing oxidative stress levels.

Repeated bouts of ischemia in the heart lead to fibrosis and eventually to heart failure. Although certain genes, such as <em>SOD</em> or hemoxygenase and antisense to AT(1)R, ACE, and (beta(1)-AR can provide short-term protection of the heart from ischemia, there is no known mechanism for constantly responding to repeated incidences of ischemia. We hypothesized that a "vigilant vector," designed to be expressed specifically in the heart and switch on therapeutic genes only during hypoxia, would provide cardioprotection. To attain cardiac specificity, we inserted an MLC2v promoter into an adeno-associated virus (AAV) designed to deliver AS to AT(1)R and gfp. In in vitro experiments in cardiomyocytes (H9C2 cells), the MLC2v-AAV-gfp drove gene expression in all cells at levels comparable to a cytomegalovirus (CMV) promoter. In in vivo experiments, the rAAV-MLC2v-gfp was injected intravenously into mice or rats. Green fluorescence protein (GFP) DNA was located in kidney, heart (right and left ventricle), lung, adrenal and spleen. GFP mRNA, however, was expressed only in the heart and absent in other tissues. To switch on the rAAV transgene during ischemia, we inserted a hypoxia response element (HRE). This upregulates transcription when O(2) levels are low. Thus, there are 4 components to the vigilant vector; a gene switch (HRE), a heart-specific promoter (MLC2v), a therapeutic gene (AS-AT(1)R) and a reporter gene (gfp). To silence or lower basal level of expression while retaining specificity, we have reduced the length of the MLC2v promoter from <em>3</em> kb to 1775 bp or 281 bp. The truncated promoter is equally effective in heart specific expression. Preliminary studies with the rAAV-HRE-gfp in vitro show an increased expression in 1% O(2) in 4 to 6 hours. By adding additional hypoxia-inducible factor (HIFalpha) (5 microg), the MLC2v-gfp expression is increased by 4-fold in 1% O(2). Further amplification of the gene to 400-fold in 1% O(2) can be achieved with a double plasmid. The construct may serve as a prototype "vigilant vector" to switch on therapeutic genes in specific tissue with physiological signals.

Antioxidant enzymes from S. mansoni, cytosolic Cu-Zn superoxide dismutase (CT-<em>SOD</em>), signal-peptide-containing <em>SOD</em> (SP-<em>SOD</em>), glutathione peroxidase (GPX), and glutathione transferase (GST) were compared for their relative levels of transcript expression throughout development in a semiquantitative reverse transcriptase-polymerase chain reaction assay. All of the antioxidant enzymes exhibited a similar pattern of developmental regulation. Adult worms have the highest level of specific mRNA compared with larval stages. GST shows the highest level of expression, being approximately 10-fold more abundant than CT-<em>SOD</em> and SP-<em>SOD</em> and 100-fold more abundant than GPX. This order of expression was nearly consistent for all the developmental stages studied. To localize the antioxidant enzymes, immunofluorescence staining was performed on <em>3</em>-hr schistosomula and adult worms. GPX, SP-<em>SOD</em>, and CT-<em>SOD</em> were all found to be associated with the adult tegument and gut epithelium. SP-<em>SOD</em> was also associated with organelle and cell membranes of parenchymal cells and interestingly with the spines of adult worms. Schistosomula, on the other hand, showed little immunofluorescence. These studies further demonstrate the developmental regulation of antioxidant enzymes and localize them to the host-parasite interface, supporting the notion that they have a role in allowing adult worms to evade immune attack.

BACKGROUND

Danggui-Shaoyao-San (DSS), a famous traditional Chinese medicine formula consisting of six herbal medicines, has been used to treat gynecological disorders and neural dysfunctions.

OBJECTIVE

The present study was carried out to investigate the effects of DSS on cognitive ability and oxidative stress-related neuronal apoptosis in the hippocampus of aging mice induced by d-galactose (d-gal) to elucidate the underlying molecular mechanisms.

METHODS

Ethanol extract of DSS (DE) were orally administered to d-gal-induced senescent mice for six weeks. The cognitive ability was determined by the methods of step-down type passive avoidance test and Morris water maze test. The activities of superoxide dismutase (<em>SOD</em>) and nitric oxide synthase (NOS), and levels of carbonyl protein (CP), glutathione (GSH), malondialdehyde (MDA) and nitric oxide (NO) were also examined. Furthermore, the expression of apoptotic related proteins in hippocampus of d-gal-treated mice, such as Bcl-2, Bax and caspase-<em>3</em> proteins, were determined by immunohistochemistry.

RESULTS

DE at the doses of 1.8, <em>3</em>.6 and 7.2g/kg significantly enhanced the cognitive performances and restored the abnormal activities of <em>SOD</em> and NOS and levels of CP, MDA, GSH and NO induced by d-gal. Moreover, the neural apoptosis in the hippocampus of d-gal-treated mice was improved by DE through regulating the expression of Bcl-2, Bax and caspase-<em>3</em>.

CONCLUSIONS

These results demonstrate that DE has neuroprotective effects in d-gal-induced senescent mice by ameliorating oxidative stress induced neuronal apoptosis in the brain.

Optineurin (OPTN) is a multifunctional protein involved in vesicular trafficking, signal transduction and gene expression. OPTN mutations were described in eight Japanese patients with familial and sporadic amyotrophic lateral sclerosis (FALS, SALS). OPTN-positive inclusions co-localising with TDP-4<em>3</em> were described in SALS and in FALS with <em>SOD</em>-1 mutations, potentially linking two pathologically distinct pathways of motor neuron degeneration. We have explored the abundance of OPTN inclusions using a range of antibodies in postmortem tissues from 1<em>3</em>8 cases and controls including sporadic and familial ALS, frontotemporal lobar degeneration (FTLD) and a wide range of neurodegenerative proteinopathies. OPTN-positive inclusions were uncommon and detected in only 11/<em>3</em>2 (<em>3</em>4%) of TDP-4<em>3</em>-positive SALS spinal cord and 5/15 (<em>3</em><em>3</em>%) of FTLD-TDP. Western blot of lysates from FTLD-TDP frontal cortex and TDP-4<em>3</em>-positive SALS spinal cord revealed decreased levels of OPTN protein compared to controls (p < 0.05), however, this correlated with decreased neuronal numbers in the brain. Large OPTN inclusions were not detected in FALS with <em>SOD</em>-1 and FUS mutation, respectively, or in FTLD-FUS cases. OPTN-positive inclusions were identified in a few Alzheimer's disease (AD) cases but did not co-localise with tau and TDP-4<em>3</em>. Occasional striatal neurons contained granular cytoplasmic OPTN immunopositivity in Huntington's disease (HD) but were absent in spinocerebellar ataxia type <em>3</em>. No OPTN inclusions were detected in FTLD-tau and α-synucleinopathy. We conclude that OPTN inclusions are relatively rare and largely restricted to a minority of TDP-4<em>3</em> positive ALS and FTLD-TDP cases. Our results do not support the proposition that OPTN inclusions play a central role in the pathogenesis of ALS, FTLD or any other neurodegenerative disorder.

Capacitation of spermatozoa is essential for fertilization and is visually characterized by hyperactivated motility. Previous reports have shown that foetal cord serum (FCS) and superoxide anion, O2.-, can trigger human sperm hyperactivation (HA) and capacitation and that superoxide dismutase (<em>SOD</em>) could prevent these processes. We investigated further the role of O2.- and FCS components in human sperm HA and capacitation. Percoll-washed spermatozoa were incubated, at <em>3</em>7 degrees C, in Ham's F-10 medium with 7.5% of FCS, dialyzed FCS >> 12 kD), ultrafiltrate from FCS (FCSu; < <em>3</em> kD), or xanthine + xanthine oxidase + catalase (X +XO + cat). Spermatozoa incubated with FCSu were also supplemented with catalase to prevent the loss of motility often observed after 2-<em>3</em> h of incubation. FCS and dialyzed FCS induced significant levels of HA (10 +/- 1% and 7.7 +/- 0.7%, respectively) that were, however, lower than those observed with FCSu (19 +/- 1%) or X + XO + cat (16 +/- 2%). Similar results were obtained when the lysophosphatidylcholine-induced acrosome reaction (LPC-AR, a measure of sperm capacitation) was evaluated. The presence of <em>SOD</em> in the incubation medium blocked the induction of HA and capacitation by FCS, FCSu, X + XO + cat, as well as the spontaneous HA and capacitation. The enzymatic activity of <em>SOD</em> was needed for the prevention of these processes. Desferrioxamine, up to 100 microM, had no effect on HA and LPC-AR induced by FCSu and X + XO + cat. Addition of <em>SOD</em> to already hyperactivated spermatozoa reversed the HA. These data suggest that spermatozoa need a sustained O2.- generation to maintain HA and proceed to capacitation. We hypothesize that FCSu or the O2.- generated by X + XO + cat activate enzymes, possibly a reduced nicotinamide adenine dinucleotide phosphate [NAD(P)H] oxidase at the level of sperm membrane.

BACKGROUND

It is clear that reactive oxygen species (ROS) produced during skeletal muscle contraction have a regulatory role in skeletal muscle adaptation to endurance exercise. However, there is much controversy in the literature regarding whether attenuation of ROS by antioxidant supplementation can prevent these cellular adaptations. Therefore, the aim of this study was to determine whether vitamin C and E supplementation attenuates performance and cellular adaptations following acute endurance exercise and endurance training.

METHODS

A double-blinded, placebo-controlled randomized control trial was conducted in eleven healthy young males. Participants were matched for peak oxygen consumption (VO 2peak) and randomly allocated to placebo or antioxidant (vitamin C (2 × 500 mg/day) and E (400 IU/day)) groups. Following a four-week supplement loading period, participants completed acute exercise (10 × 4 min cycling at 90% VO 2peak, 2 min active recovery). Vastus lateralis muscle samples were collected pre-, immediately-post- and <em>3</em>h-post-exercise. Participants then completed four weeks of training (<em>3</em> days/week) using the aforementioned exercise protocol while continuing supplementation. Following exercise training, participants again completed an acute exercise bout with muscle biopsies.

RESULTS

Acute exercise tended to increase skeletal muscle oxidative stress as measured by oxidized glutathione (GSSG) (P=0.058) and F2-isoprostanes (P=0.056), with no significant effect of supplementation. Acute exercise significantly increased mRNA levels of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α), mitochondrial transcription factor A (TFAM) and PGC related coactivator (PRC), with no effect of supplementation. Following endurance training, supplementation did not prevent significantly increased VO 2peak, skeletal muscle levels of citrate synthase activity or mRNA or protein abundance of cytochrome oxidase subunit 4 (COX IV) (P<0.05). However, following training, vitamin C and E supplementation significantly attenuated increased skeletal muscle superoxide dismutase (SOD) activity and protein abundance of SOD2 and TFAM.

CONCLUSIONS

Following acute exercise, supplementation with vitamin C and E did not attenuate skeletal muscle oxidative stress or increased gene expression of mitochondrial biogenesis markers. However, supplementation attenuated some (SOD, TFAM) of the increased skeletal muscle adaptations following training in healthy young men.

The antioxidant properties of three successive extracts of Caesalpinia digyna Rottler root and the isolated compound, bergenin, were tested using standard in vitro and in vivo models. The amount of the total phenolic compounds present was also determined. The successive methanol extract of Caesalpinia digyna root (CDM) exhibited strong scavenging effect on 2,2-diphenyl-2-picryl hydrazyl (DPPH) free radical, 2,2'-azino-bis(<em>3</em>-ethylbenzo-thiazoline-6-sulphonic acid) diammonium salt (ABTS) radical cation, hydrogen peroxide, nitric oxide, hydroxyl radical and inhibition of lipid peroxidation. The free radical scavenging effect of CDM was comparable with that of reference antioxidants. The CDM having the highest content of phenolic compounds and strong free radical scavenging effect when administered orally to male albino rats at 100, 200 and 400mg/kg body weight for 7 days, prior to carbontetrachloride (CCl(4)) treatment, caused a significant increase in the levels of catalase (CAT) and superoxide dismutase (<em>SOD</em>) and significant decrease in the levels of lipidperoxidation (LPO) in serum, liver and kidney in a dose dependent manner, when compared to CCl(4) treated control. These results clearly indicate the strong antioxidant property of Caesalpinia digyna root. The study provides a proof for the ethnomedical claims and reported biological activities. The plant has, therefore, very good therapeutic potential.

OBJECTIVE

To investigate the modulatory effect of sodium hydrosulfide on lung tissue-oxidized glutathione and total antioxidant capacity in the development of hypoxic pulmonary hypertension (HPH).

METHODS

After 21 d of hypoxia, the mean pulmonary artery pressure was measured by cardiac catheterization. The plasma H2S level and production of H2S in the lung tissues were determined by using a spectrophotometer. The lung homogenates were assayed for total antioxidant capacity (T-AOC), superoxide dismutase (SOD), oxidized glutathione (GSSG), reduced glutathione and malonaldehyde by colorimetry. The mRNA level of SOD was analyzed by real-time PCR, and the SOD expression was detected by Western blotting.

RESULTS

In the hypoxia group, the plasma H2S concentration and H2S production in the lung was significantly decreased compared with the control group (187.2+/-13.1 vs 299.6+/-12.4 micromol/L; 0.138+/-0.013 vs 0.289+/-0.036 nmol x mg(-1) x min(-1), P<0.01). The administration of sodium hydrosulfide could reduce the mean pulmonary artery pressure by 31.2% compared with the hypoxia group (P<0.01). Treatment with sodium hydrosulfide decreased GSSG, and the T-AOC level of the lung tissues was enhanced compared with the hypoxia group (P<0.05). There were no significant changes in the lung tissue SOD mRNA level, protein level, and its activity among the 3 groups.

CONCLUSIONS

Oxidative stress occurred in the development of HPH and was accompanied by a decrease in the endogenous production of H2S in the lung tissues. H2S acted as an antioxidant during the oxidative stress of HPH partly as a result of the attenuated GSSG content.

1. The purpose of the present study was to investigate the changes in superoxide dismutase (<em>SOD</em>) isoenzyme (Mn(2+)-<em>SOD</em> and Cu2+, Zn(2+)-<em>SOD</em>) activities, contents and mRNA expressions in rat skeletal muscle during endurance training and a single bout of exercise. 2. Thirty-eight male Wistar rats were divided into untrained (U) and trained (T) groups. The T group rats were treadmill-trained for 9 weeks. The activity, content and mRNA expression of Mn(2+)-<em>SOD</em> and Cu2+, Zn(2+)-<em>SOD</em> were determined in the soleus muscle of each rat. <em>3</em>. Mn(2+)-<em>SOD</em> activity and content in the T group were significantly higher than in the U group, both at rest (22 and 21%, respectively) and after exercise (24 and 46%, respectively), while a single bout of exercise affected neither the activity nor content of Mn(2+)-<em>SOD</em> in either group. 4. The content of Cu2+,Zn(2+)-<em>SOD</em> in both groups was not different at rest and after exercise, although its activity at rest was significantly higher in the T group than in the U group (by 29%). 5. After exercise, the expression of Mn(2+)-<em>SOD</em> mRNA was markedly attenuated only in the U group (49%); the expression of Cu2+,Zn(2+)-<em>SOD</em> mRNA was not influenced by exercise. 6. Our results suggest that adequate endurance training increases both the activity and content of Mn(2+)-<em>SOD</em> and that untrained rats are rather susceptible to oxidative stress during physical exercise. It thus appears that Mn(2+)-<em>SOD</em> provides a reliable index of physical training. 7. The results obtained in the present study also suggest that muscle has the capacity of responding to training in such a manner as to reduce the potential harm arising from the accumulation of oxygen free radicals resulting from enhanced metabolic activity.

OBJECTIVE

We tested whether gender influences cerebrovascular responses to angiotensin II (AngII) and the role(s) of Nox2.

METHODS

AngII-stimulated superoxide (O(2)(-)) production by cerebral arteries from male and female wild-type (WT) and Nox2(-/-) mice was measured using lucigenin- or L-012-enhanced chemiluminescence. Hydrogen peroxide (H(2)O(2)) production was measured using Amplex Red fluorescence. Western Blotting was used to measure expression of Nox2, endothelial nitric oxide synthase (eNOS), angiotensin receptors (AT(1) and AT(2)), and superoxide dismutases (<em>SOD</em>1-<em>3</em>). Immunofluorescence was used to localize Nox2 in middle cerebral arteries (MCA). Vascular responses to AngII were assessed in a perfusion myograph. AngII-stimulated O(2)(-) and H(2)O(2) production by cerebral arteries from female WT mice was approximately 75% to 85% lower than in males (P<0.05). O(2)(-) production was approximately 60% lower in Nox2(-/-) versus WT males (P<0.05), whereas Nox2 deletion did not affect O(2)(-) production in females. Expression of Nox2, eNOS, AT receptors, and <em>SOD</em> isoforms was similar between genders. Nox2 immunofluorescence was similarly localized in adventitial and endothelial cells of MCA from both genders. AngII elicited smaller contractions of MCA from females vs males (P<0.05). Contractions were reduced in male, but not female, Nox2(-/-) mice (P<0.05). The <em>SOD</em> mimetic, tempol, potentiated contractions to AngII in male WT mice (P<0.05), whereas the <em>SOD</em>/catalase mimetic, EUK-1<em>3</em>4, virtually abolished contractions (P<0.05).

CONCLUSIONS

AngII-stimulated O(2)(-) and H(2)O(2) production are greater in cerebral arteries from male versus female mice, and are associated with greater contractions to AngII mediated by H(2)O(2). These gender differences are dependent on the expression of Nox2.

To investigate the temporal sequence of physiological reactions of garlic (Allium sativum) to cadmium (Cd) treatment, seedlings developed from cloves were grown in increasing concentrations of CdCl2, ranging from 1-10 mM, for up to 8 days in sand. Analysis of Cd uptake indicated that most Cd accumulated in roots, but some was also translocated and accumulated in leaves at longer exposure time (after 12h) and higher concentrations (5 and 10mM) of CdCl2. Changes in activities of antioxidative enzymes, including superoxide dismutase (<em>SOD</em>), peroxidase (POD) and catalase (CAT), were characterized in leaves of garlic seedlings. Cd (5 and 10 mM) initially inhibited the activities of <em>SOD</em> and CAT but thereafter recovered or even increased compared with control plants. POD activities at 5 and 10 mM of Cd increased more than <em>3</em>-4 times over control plants within 12 h and then dropped, but were still higher than controls at the end of the experiment. Otherwise lipid peroxidation enhanced with the increasing of incubation time and concentrations of external Cd. Leaves exposed to 1 mM CdCl2 showed a less pronounced response and only a small reduction in shoot growth. These results suggested that in leaves of garlic seedlings challenged by CdCl2 at higher concentrations, induction of these various enzymes is part of a general defense strategy to cope with overproduction of reactive oxygen. The possible mechanism of antioxidative enzymes changing before Cd accumulation in leaves of garlic seedlings is discussed.

The green tea flavonoid epigallocatechin gallate (EGCG) is demonstrated in this study to modulate FoxO transcription factors in human skin fibroblasts in culture. EGCG at 1 microM stimulated FoxO transcription factor nuclear accumulation and DNA binding activity. This effect was masked at higher EGCG concentrations (100 microM) by EGCG-derived hydrogen peroxide generated in cell culture media that stimulates phosphoinositide-<em>3</em>'-kinase (PI<em>3</em>K)/Akt signaling to attenuate FoxO activity, involving FoxO phosphorylation, nuclear exclusion and attenuation of DNA binding activity. Like low concentrations of EGCG, harmine, an inhibitor of the FoxO kinase DYRK1a, stimulated FoxO nuclear accumulation and DNA binding activity. Exposure of Caenorhabditis elegans worms to EGCG caused nuclear accumulation of the FoxO ortholog, DAF-16, and enhanced expression of the DAF-16 target gene, <em>sod</em>-<em>3</em>. In line with the role of FoxO/DAF-16 in the control of life span, C. elegans mean and maximum life span were enhanced by 20% and 1<em>3</em>%, respectively, by EGCG.

BACKGROUND

Experimental studies have shown that anthocyanins may exert pleiotropic effects. The aim of the study was to determine the influence of Aronia melanocarpa extract on blood pressure and serum concentration of endothelin-1 (ET-1), lipids, glucose, uric acid, C-reactive protein (CRP), fibrinogen, the antioxidant enzymes catalase (CAT), superoxide dysmutase (SOD), and glutathione peroxidase (GSH-Px), and lipid peroxidation (thiobarbituric acid-reacting substrates, TBARS) in erythrocytes of patients with metabolic syndrome (MS).

METHODS

The study comprised 22 healthy volunteers and 25 patients with MS. Patients with MS were treated with aronia extract (3 x 100 mg/day) for two months. The above parameters were measured.

RESULTS

After two months of therapy, statistically significant decreases were observed in SBP (143.40+/-7.87 vs. 131.83+/-12.24 mmHg, p<0.001), DBP (87.20+/-9.9 vs. 82.13+/-10.33 mmHg, p<0.05), ET-1 (2.44+/-0.51 vs. 1.74+/-0.42 pg/ml, p<0.001), TC (242.80+/-34.48 vs. 227.96+/-33.07 mg/dl, p<0.001), LDL-C (158.71+/-35.78 vs. 146.21+/-34.63 mg/dl, p<0.01), TG (215.92+/-63.61 vs. 187.58+/-90 mg/dl, p<0.05), TBARS (0.0712+/-0.0191 vs. 0.0362+/-0.0135 micromol/g-Hb, p<0.001), and CAT (261.30+/-59.78 vs. 213.34+/-47.36 U/mg-Hb) and significant increases in SOD (2380.63+/-419.91 vs. 3066.53+/-542.24 U/g-Hb, p<0.001), GSH-Px (12.60+/-5.97 vs. 19.18+/-9.09 U/g-Hb, p<0.01), and fibrinogen levels (249.20+/-27.17 vs. 276.67+/-57.41 mg/dl, p<0.05) compared with the baseline values.

CONCLUSIONS

Aronia extract may be of benefit to patients with MS. This seems to result from the influence of anthocyanins and possibly other flavonoids on blood pressure, serum level of ET-1, lipids, and oxidative status (GSH-Px, SOD, TBARS).

Single-walled carbon nanotubes (SWCNTs) are potential candidates in many biomedical applications. However, many reports demonstrated its potential toxicity to human and other biological systems. Our study has demonstrated that SWCNTs can induce apoptosis and oxidative damage on PC12 cells, an in vitro model of neuronal cells. In the present study, we for the first time investigated the neuroprotective effects of vitamin E (VE) on SWCNT-induced neurotoxicity in cultured PC12 cells. Vitamin E (0.01-2mM) increased PC12 cells viability and significantly attenuated SWCNTs-induced apoptotic cell death in a time and dose-dependent manner, as demonstrated by <em>3</em>-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, lactate dehydrogenase (LDH) release and morphological observation. The presence of VE inhibited the formation of reactive oxygen species (ROS), decreased the level of lipid peroxide, elevated the level of glutathione (GSH) and activities of superoxide dismutase (<em>SOD</em>), glutathione peroxidase (GPx), and catalase (CAT). Additionally, VE blocked the reduction in the mitochondrial membrane potential and the activation of caspase-<em>3</em>. VE prevented the down-regulation of Bcl-2 expression and up-regulation of Bax expression induced by SWCNTs in PC12 cells. In summary, VE might protect PC12 cells from the injury induced by SWCNTs through the down-regulation of oxidative stress and prevention of mitochondrial-mediated apoptosis.

Reactive oxygen species (ROS) may play key roles in vascular inflammation and atherogenesis in patients with diabetes. In this study, xanthine oxidase (XO) system was examined as a potential source of superoxide in mice with streptozotocin (STZ)-induced experimental diabetes. Plasma XO activity increased <em>3</em>-fold in diabetic mice (50 +/- <em>3</em><em>3</em> microU/ml) 2 weeks after the onset of diabetes, as compared with non-diabetic control mice (15 +/- 6 microU/ml). In vivo superoxide generation in diabetic mice was evaluated by an in vivo electron spin resonance (ESR)/spin probe method. Superoxide generation was significantly enhanced in diabetic mice, and the enhancement was restored by the administration of superoxide dismutase (<em>SOD</em>) and 4,5-dihydroxy-1,<em>3</em>-benzene disulfonic acid (Tiron), which was reported to scavenge superoxide. Pretreatment of diabetic mice with XO inhibitors, allopurinol and its active metabolite oxipurinol, normalized the increased superoxide generation. In addition, there was a correlation (r = 0.78) between the level of plasma XO activity and the relative degree of superoxide generation in diabetic and non-diabetic mice. Hence, the results of this study strongly suggest that superoxide should be generated through the increased XO seen in the diabetic model mice, which may be involved in the pathogenesis of diabetic vascular complications.

The basal expression patterns of NO synthase (NOS; endothelial [eNOS], neuronal [nNOS], and cytokine-inducible [iNOS]) and superoxide dismutase (<em>SOD</em>; extracellular membrane bound [EC<em>SOD</em>], Mn<em>SOD</em>, and CuZn<em>SOD</em>) isoforms in ferret heart (tissue sections and isolated myocytes) were determined by immunofluorescent localization. We demonstrate the following for the first time in the mammalian heart: (1) heterogeneous expression patterns of the <em>3</em> NOS and <em>3</em> <em>SOD</em> isoforms among different tissue and myocyte types; (2) colocalization of eNOS and EC<em>SOD</em> at both the tissue and myocyte levels; (<em>3</em>) a significant gradient of eNOS and EC<em>SOD</em> expression across the left ventricular (LV) wall, with both enzymes being highly expressed and colocalized in LV epicardial myocytes but markedly reduced in LV endocardial myocytes; and (4) specific subcellular localization patterns of eNOS and the <em>3</em> <em>SOD</em> isoforms. In particular, eNOS and EC<em>SOD</em> are demonstrated (electron and confocal microscopy) to be specifically localized to the sarcolemma of ventricular myocytes. Similar heterogeneous eNOS and EC<em>SOD</em> expression patterns were also obtained in human LV tissue sections, underscoring the general importance of these novel findings. Our data suggest a strong functional correlation between the activities of sarcolemmally localized myocyte eNOS and EC<em>SOD</em> in governing NO*/O(2-) interactions and suggest that NO-related modulatory effects on cardiac myocyte protein and/or ion channel function may be significantly more complex than is presently believed.

The objective of this work was to test the hypothesis that endurance training may be protective against in vivo doxorubicin (DOX)-induced cardiomyopathy through mitochondria-mediated mechanisms. Forty adult (6-8 wk old) male Wistar rats were randomly divided into four groups (n = 10/group): nontrained, nontrained + DOX treatment (20 mg/kg), trained (14 wk of endurance treadmill running, 60-90 min/day), and trained + DOX treatment. Mitochondrial respiration, calcium tolerance, oxidative damage, heat shock proteins (HSPs), antioxidant enzyme activity, and apoptosis markers were evaluated. DOX induces mitochondrial respiratory dysfunction, oxidative damage, and histopathological lesions and triggers apoptosis (P < 0.05, n = 10). However, training limited the decrease in state <em>3</em> respiration, respiratory control ratio (RCR), uncoupled respiration, aconitase activity, and protein sulfhydryl content caused by DOX treatment and prevented the increased sensitivity to calcium in nontrained + DOX-treated rats (P < 0.05, n = 10). Moreover, training inhibited the DOX-induced increase in mitochondrial protein carbonyl groups, malondialdehyde, Bax, Bax-to-Bcl-2 ratio, and tissue caspase-<em>3</em> activity (P < 0.05, n = 10). Training also increased by approximately 2-fold the expression of mitochondrial HSP-60 and tissue HSP-70 (P < 0.05, n = 10) and by approximately 1.5-fold the activity of mitochondrial and cytosolic forms of <em>SOD</em> (P < 0.05, n = 10). We conclude that endurance training protects heart mitochondrial respiratory function from the toxic effects of DOX, probably by improving mitochondrial and cell defense systems and reducing cell oxidative stress. In addition, endurance training limited the DOX-triggered apoptosis.

Placenta is a tissue unique to pregnancy and despite its major role in pregnancy, little is known about the proteome changes within placenta during pregnancy-related diseases such as pre-eclampsia (PE). Therefore, the aim of this study is the analysis of proteome differences between pre-eclamptic and normal full-term placentas. To achieve this goal, five normal and five severe pre-eclamptic placentas were included in this study. Total placental proteins were extracted and subjected to two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). After staining, the gels were scanned and the protein spots were analysed using Image Master 2D Platinum Software. Non-parametric Mann-Whitney test was used for analysis of the mean intensity differences of the spots between normal and pre-eclamptic placentas. Statistical analysis indicated that 17 spots were differently expressed in pre-eclamptic compared with normal placentas (p<0.05). Using Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI TOF/TOF) mass analysis, 11 out of 17 spots were identified. Among them, four proteins (chloride intracellular channel <em>3</em>, apolipoprotein A-I, transthyretin (TTR) and protein disulphide isomerase) were up-regulated while seven (peroxiredoxin 2, peroxiredoxin <em>3</em>, Hsc 70, Cu/Zn-superoxide dismutase (<em>SOD</em>-1), actin gamma 1 propeptide, chain A of enoyl-coenzyme A hydratase and HSP gp96) showed decreased expression in PE in comparison with normal placentas. In conclusion, down-regulation of proteins with anti-oxidant activities (peroxiredoxin 2 and peroxiredoxin <em>3</em>) and altered expression of stress-response proteins (Hsc 70, Hsp gp96 and protein disulphide isomerase) might play an important role in the pathogenesis of PE.

Increased oxidative stress (SOX), inflammation and prevalence of cardiovascular disease (CVD) have been reported in end-stage renal disease (ESRD), but their associations with kynurenine (KYN) pathway activation remain unknown. We determined the plasma concentrations of tryptophan (TRP), KYN, <em>3</em>-hydroxykynurenine (<em>3</em>-HKYN); two distinct SOX markers: Cu/Zn superoxide dismutase (Cu/Zn <em>SOD</em>) and total peroxide; and high sensitivity C-reactive protein (hs CRP) as a indicator of inflammation in 146 ESRD patients and healthy controls. Analysis of TRP degradation through the KYN pathway demonstrated that in uremia the concentrations of this aminoacid were decreased by 40-60% in comparison with controls. In contrast, the plasma levels of KYN and <em>3</em>-HKYN in ESRD patients were increased by <em>3</em>2-96% and 184-<em>3</em>06%, respectively. These changes were accompanied by significant increase in the kyn/trp ratios by 140-240%, and <em>3</em>-hkyn/kyn ratios by 40-154% in uremics compared to controls. ESRD patients showed a significant increase in Cu/Zn <em>SOD</em>, total peroxide and hs CRP levels between controls and all patients group. KYN and <em>3</em>-HKYN were positively associated with inflammation and SOX markers in uremics. Logistic regression analysis showed that age, gender, presence of DM (all p<0.001), elevated hs CRP (p<0.01) and <em>3</em>-HKYN levels (p<0.05) were independently associated with the presence of CVD in this population. These results suggest a relationship between KYN pathway activation and increased SOX, inflammation and CVD prevalence in ESRD patients.

METHODS

Placebo for <em>3</em> months, followed by <em>3</em>0 mg/day zinc gluconate in identical capsules.

METHODS

Diabetic out patients clinic at the University Hospital, Grenoble.

METHODS

Diabetic patients cared for type I diabetes mellitus. 22 patients began the study, 4 dropped out. 10 patients suffered of an early retinopathy, 8 patients had no retinopathy.

METHODS

In this order: T0 biological measurements, <em>3</em> months placebo treatment, T1 biological measurements, <em>3</em> months zinc gluconate treatment, T2 biological measurements. Plasma Zn, Cu, Se, thiobarbituric acid reactants and antioxidant enzymes were measured [plasma and red glutathione peroxidase (Se-GPx), red cell superoxide dismutase (Cu-Zn-SOD)].

RESULTS

Lower plasma zinc level in the two groups. An increase in zinc level was observed and was more important in diabetic patients with no retinopathy (P = 0.05). The thiobarbituric acid reactants were above the reference values in all the patients, and were decreased at T2 (P < 0.05). Increase of GPx activity after zinc supplementation in patients with retinopathy.

CONCLUSIONS

Zinc deficiency in insulin-dependent diabetic patients is corrected by a zinc supplementation. Moreover this supplementation decreases lipid peroxidation. The effects of zinc are different in diabetic patients with or without retinopathy. The increase in Se-GPx activity observed in patients with retinopathy could be linked to the protective effect of zinc on the protein itself.

Tellurite (TeO<em>3</em>(2-)) is the most toxic and soluble oxyanion among tellurium (Te) compounds. The effects of the metalloid anion on the oxidative stress response of the obligate aerobe Pseudomonas pseudoalcaligenes KF707 were investigated. Cells treated with sub-lethal concentrations of TeO<em>3</em>(2-) showed neither adaptation to it nor cross-protection against oxidants such as 1,1'-4,4'-bipyridinium dichloride (paraquat, PQ2+), diazenedicarboxylic acid bis-N,N-dimethylamide (diamide), tert-butyl hydroperoxide (tBH) and hydrogen peroxide (H2O2). Notably, TeO<em>3</em>(2-) exerted a synergic effect on the toxicity of these latter oxidants. Tellurite was shown to decrease the cellular content of reduced thiols (RSH) with a consequent increase in the production of reactive oxygen species (ROS) and stimulation of the superoxide dismutase (<em>SOD</em>) activity. However, since the time course of ROS production by TeO<em>3</em>(2) (t1/2>> <em>3</em>0 min) was much slower than that with PQ2+ and/or diamide (t1/2 <or= 10 min), in the former case the <em>SOD</em> activity was poorly activated. We conclude that in P. pseudoalcaligenes KF707 cells: (1) the TeO<em>3</em>(2-) acts as a pro-oxidant by stimulating ROS production; (2) the release of superoxide oxyanions is directly linked to the mechanism of toxicity; (<em>3</em>) TeO<em>3</em>(2-) is unable to induce an adaptive response to oxidative stress.

OBJECTIVE

The purpose of the current study was to analyze both serum and salivary composition and oxidative stress markers in Type 1 diabetes mellitus (DM) patients.

METHODS

Twenty consenting patients with DM but otherwise healthy patients aged 1<em>3</em>-19 years and 12 healthy controls, matching in age and gender (Group 1), participated in the study. The patients were divided according to those who had controlled diabetes mellitus (Group 2) or uncontrolled diabetes mellitus (Group <em>3</em>). All were analyzed for saliva composition and antioxidants. Saliva was also analyzed for its levels of superoxide dismutase (<em>SOD</em>) and amylase activity, total IgA and total IgG concentrations and potassium, phosphorus, magnesium and calcium electrolyte concentrations.

RESULTS

A significant correlation was found between the severity of the DM/HbA1c values and the increase in both salivary and/or serum antioxidants (peroxidase, <em>SOD</em> and TAS), and the various TCL parameters (H1, H<em>3</em>, pre-incubation and oxygenation-potential).

CONCLUSIONS

The two most important findings of the current study relate to the role of oxidative stress in the pathogenesis of Type 1 diabetes mellitus and to the involvement of salivary glands in the disease. The profound effects of DM on salivary antioxidant parameters may be also of great importance in respect to the diagnosis and evaluation of the disease. The correlation between altered salivary parameters and the severity of the disease may indicate that evaluation of the salivary status of DM patients as part of the assessment of their disease activity and severity is warranted.

Tyrosine nitration is a posttranslational modification observed in many pathologic states that can be associated with peroxynitrite (ONOO(-)) formation. However, in vitro, peroxynitrite-dependent tyrosine nitration is inhibited when its precursors, superoxide (O(2)*(-)) and nitric oxide ((*)NO), are formed at ratios (O(2)*(-)/(*)NO) different from one, severely questioning the use of <em>3</em>-nitrotyrosine as a biomarker of peroxynitrite-mediated oxidations. We herein hypothesize that in biological systems the presence of superoxide dismutase (<em>SOD</em>) and the facile transmembrane diffusion of (*)NO preclude accumulation of O(2)*(-) and (*)NO radicals under flux ratios different from one, preventing the secondary reactions that result in the inhibition of <em>3</em>-nitrotyrosine formation. Using an array of reactions and kinetic constants, computer-assisted simulations were performed in order to assess the flux of <em>3</em>-nitrotyrosine formation (J(NO(2(-))Y)) during exposure to simultaneous fluxes of superoxide (J(O(2)*(-))) and nitric oxide (J((*)NO)), varying the radical flux ratios (J(O(2)*(-))/ J((*)NO)), in the presence of carbon dioxide. With a basic set of reactions, J(NO(2(-))Y) as a function of radical flux ratios rendered a bell-shape profile, in complete agreement with previous reports. However, when superoxide dismutation by <em>SOD</em> and (*)NO decay due to diffusion out of the compartment were incorporated in the model, a quite different profile of J(NO(2(-))Y) as a function of the radical flux ratio was obtained: despite the fact that nitration yields were much lower, the bell-shape profile was lost and the extent of tyrosine nitration was responsive to increases in either O(2)*(-) or (*)NO, in agreement with in vivo observations. Thus, the model presented herein serves to reconcile the in vitro and in vivo evidence on the role of peroxynitrite in promoting tyrosine nitration.