Four types of superoxide dismutase (<em>SOD</em>) derivatives such as <em>SOD</em>-carboxymethyl dextran conjugate, <em>SOD</em>-diethylaminoethyl dextran conjugate, galactosylated <em>SOD</em> and mannosylated <em>SOD</em> were synthesized and their potential for selective targeting to organs or cells was evaluated in mice by pharmacokinetic analysis. All <em>SOD</em> derivatives retained 50 to 80% of the original enzymatic activity and were stable during incubation with mouse serum retaining enzymatic activity greater than 80% for <em>3</em> hr. After intravenous injection, native <em>SOD</em> was rapidly excreted into urine and no significant accumulation was observed in the organs except the kidney. <em>SOD</em>-carboxymethyl dextran conjugate gave a long plasma half-life because of impaired glomerular filtration and tissue interaction. By contrast, galactosylated-<em>SOD</em> and mannosylated-<em>SOD</em> were very rapidly eliminated from the circulation and taken up by parenchymal and nonparenchymal cells of the liver, respectively, via receptor-mediated endocytosis. These uptake processes were nonlinear and hepatic uptake clearance decreased as the dose increased, although almost complete extraction was obtained at a dose of 0.1 mg/kg. Furthermore, the accumulation in kidney of both glycosylated <em>SODs</em> was drastically decreased due to reduced renal proximal tubular reabsorption and also enhanced hepatic clearance. <em>SOD</em>-diethylaminoethyl dextran conjugate also rapidly disappeared from plasma and distributed into liver, but its accumulation occurred due to electrostatic interaction and was nonspecific in cellular distribution. These results suggest the possibility of controlling the in vivo fate of <em>SOD</em> at a cellular level by chemical modification utilizing sugar moieties with varied physicochemical and/or biological characteristics.

1. Noradrenaline sensitivity and acetylcholine-induced relaxation were investigated in mesenteric resistance arteries from female Wistar rats (220-250 g) following exposure to isotonic supraphysiological glucose solutions (20 and 45 mM, in physiological buffer, 2 h incubation). 2. Arteries incubated in 20 mM glucose demonstrated enhanced noradrenaline sensitivity compared with those in physiological buffer. <em>3</em>. Profoundly impaired endothelium-dependent relaxation to acetylcholine was observed in arteries incubated in 20 and 45 mM glucose. 4. Indomethacin (10 microM) normalized noradrenaline sensitivity in 20 mM glucose, but unmasked an enhanced maximum response in 20 and 45 mM glucose relative to controls. 5. Addition of L-arginine (0.1 mM) prevented the abnormality of acetylcholine-induced relaxation in the 20 mM glucose medium and significantly improved relaxation in 45 mM glucose. 6. The aldose reductase inhibitor, ponalrestat (10(-5) M, ZENECA Pharmaceuticals), prevented impaired acetylcholine-mediated relaxation in 20 mM glucose and significantly improved relaxation in 45 mM glucose. 7. Indomethacin (10 microM) improved maximum relaxation but did not alter impaired sensitivity to acetylcholine in the high glucose media (20 and 45 mM). 8. Superoxide dismutase (<em>SOD</em>, 150 u ml-1) also prevented impaired acetylcholine-induced relaxation in 20 mM glucose but not in 45 mM glucose. 9. Endothelium-independent relaxation to sodium nitroprusside (SNP, 10(-9)-10(-5) mM) was normal in 20 mM glucose but was slightly, although significantly impaired by 45 mM glucose. 10. Enhanced responsiveness of rat isolated mesenteric resistance arteries to noradrenaline caused by elevated glucose would appear to be mediated through abnormal cyclo-oxygenase activity and the reduced tonic release of nitric oxide. 11. Hyperglycaemia may lead to abnormal endothelium-dependent relaxation in these arteries through several mechanisms which include a role for increased free radical production, polyol pathway activation and altered L-arginine metabolism.

Insulin-like signaling regulates developmental arrest, stress resistance and lifespan in the nematode Caenorhabditis elegans. However, the genome encodes 40 insulin-like peptides, and the regulation and function of individual peptides is largely uncharacterized. We used the nCounter platform to measure mRNA expression of all 40 insulin-like peptides as well as the insulin-like receptor daf-2, its transcriptional effector daf-16, and the daf-16 target gene <em>sod</em>-<em>3</em>. We validated the platform using 5<em>3</em> RNA samples previously characterized by high density oligonucleotide microarray analysis. For this set of genes and the standard nCounter protocol, sensitivity and precision were comparable between the two platforms. We optimized conditions of the nCounter assay by varying the mass of total RNA used for hybridization, thereby increasing sensitivity up to 50-fold and reducing the median coefficient of variation as much as 4-fold. We used deletion mutants to demonstrate specificity of the assay, and we used optimized conditions to assay insulin-like gene expression throughout the C. elegans life cycle. We detected expression for nearly all insulin-like genes and find that they are expressed in a variety of distinct patterns suggesting complexity of regulation and specificity of function. We identified insulin-like genes that are specifically expressed during developmental arrest, larval development, adulthood and embryogenesis. These results demonstrate that the nCounter platform provides a powerful approach to analyzing insulin-like gene expression dynamics, and they suggest hypotheses about the function of individual insulin-like genes.

BACKGROUND

Iron balance is critical for adequate erythropoiesis and there remains much debate concerning the optimal timing and dosage of iron therapy for haemodialysis patients receiving recombinant human erythropoietin therapy.

METHODS

In this study, we examined the influence of baseline ferritin level and intravenous infusion of 100 mg ferric saccharate on the oxidative status of the patients on maintenance haemodialysis. The levels of antioxidant enzymes and lipid peroxides were determined in erythrocytes and plasma of 50 uraemic patients on haemodialysis. These patients were divided into groups 1, 2, and <em>3</em>, based on their baseline serum ferritin levels of (<em>3</em>00, <em>3</em>01-600, and >601 microg/l, respectively.

RESULTS

We found that the mean superoxide dismutase (SOD) activities in the erythrocytes were similar in the three groups of patients and did not differ from those of the age-matched controls. On the other hand, all the haemodialysis patients showed significantly higher plasma SOD activity as compared to controls. After intravenous iron infusion, group <em>3</em> patients showed the largest decrease in plasma SOD activity. The plasma glutathione peroxidase (GSHPx) activities of the patients in all three groups and the erythrocyte GSHPx activities of the patients in the groups 2 and <em>3</em> were lower than those of the healthy controls. In all three groups of patients, no difference in GSHPx activity was found before and after intravenous iron infusion. On the other hand, we found that the average baseline levels of plasma lipid peroxides of all three groups of patients were significantly higher than that of the controls. The patients in group <em>3</em> with the highest serum ferritin levels showed the highest levels of plasma lipid peroxides. More importantly, we found that after iron infusion, the patients in all three groups, particularly those in group <em>3</em>, showed significantly elevated levels of plasma lipid peroxides.

CONCLUSIONS

We demonstrated that increased oxidative stress in the blood circulation of the uraemic patients on haemodialysis is exacerbated by the elevated baseline serum ferritin levels and intravenous iron infusion. The resultant oxidative damage may contribute to the increased incidence of atherosclerosis in the patients with end-stage renal disease on long-term haemodialysis.

The purpose of this study was to investigate the role of superoxide dismutase (<em>SOD</em>) and catalase (CAT) in brain ischemic tolerance induced by ischemic preconditioning. Forebrain cerebral ischemia was induced in rat by four vessel occlusion. The activities of the antioxidant enzymes CuZn-<em>SOD</em>, Mn-<em>SOD</em> and CAT were measured in the hippocampus, striatum and cortex after 5 min of ischemia used as a preconditioning and subsequent reperfusion, by spectrophotometric methods. In all ischemia-reperfusion groups (5 h, 1 and 2 days of reperfusion), CuZn-<em>SOD</em> activities were found to be increased if compared to the sham operated controls. The increase was significant (P < 0.05) in all reperfusion groups, particularly after 5 h of reperfusion (<em>3</em> times) in all studied brain regions; the largest increase was detected in the more vulnerable hippocampus and striatum. Very similar changes were found in Mn-<em>SOD</em> activity. The activity of CAT was increased too, but reached the peak of postischemic activity 24 h after ischemia. Our attempt to understand the mechanisms of increased <em>SOD</em> and CAT activities by application of protein synthesis inhibitor cycloheximide showed that this increase was caused by de novo synthesis of enzymes during first hours after ischemia. Our findings indicate that both major endogenous antioxidant enzymes <em>SOD</em> and CAT are synthesized as soon as 5 h after ischemia. In spite of significant upregulation of these enzymes a large number of neurons in selectively vulnerable CA1 region of hippocampus undergoes to neurodegeneration within 7 days after ischemia.

OBJECTIVE

To determine possible indications of the mechanisms involved in improved sperm parameters by zinc therapy in asthenozoospermic men.

METHODS

Forty-five men with asthenozoospermia >>or=40% immotile sperm) were randomized into four therapy groups: zinc only: n = 11; zinc + vitamin E: n = 12 and zinc + vitamins E + C: n = 14 for <em>3</em> months, and non-therapy control group: n = 8. Semen analysis was done according to WHO guidelines. Malone dialdehyde, tumour necrosis factor-alpha (TNF-alpha), total antioxidant capacity, superoxide dismutase (<em>SOD</em>) and glutathione peroxidase were determined in the semen and serum. Antisperm antibodies IgG, IgM and IgA were evaluated by immunobeads. Sperm chromatin integrity was determined by acid denaturation by acridine orange and sperm apoptosis by light and electron microscopy. The effect of zinc on in vitro induced sperm oxidative stress by NADH was evaluated.

RESULTS

Asthenozoospermia was significantly associated with oxidative stress with higher seminal malone dialdehyde (8.8 vs. 1.8 mmol/l, p < 0.001) and TNF-alpha (60 vs. 12 pg/l, p < 0.001), and low total antioxidant capacity (1.8 vs. 8.4, p < 0.01), <em>SOD</em> (0.8 vs. <em>3</em>.1, p < 0.01) and glutathione peroxidase (1.6 vs. 4.2, p < 0.05), compared to normozoospermia. Zinc therapy alone, in combination with vitamin E or with vitamin E + C were associated with comparably improved sperm parameters with less oxidative stress, sperm apoptosis and sperm DNA fragmentation index (DFI). On the whole, there was no difference in the outcome measures between zinc only and zinc with vitamin E and combination of vitamins E + C. In the in vitro experiment zinc supplementation resulted in significantly lower DFI (14-29%, p < 0.05) compared to zinc deficiency.

CONCLUSIONS

Zinc therapy reduces asthenozoospermia through several mechanisms such as prevention of oxidative stress, apoptosis and sperm DNA fragmentation.

The aim of this study was to investigate whether the effects of aging on oxidative stress markers and expression of major oxidant and antioxidant enzymes associate with impairment of renal function and increases in blood pressure. To explore this, we determined age-associated changes in lipid peroxidation (urinary malondialdehyde), plasma and urinary hydrogen peroxide (H(2)O(2)) levels, as well as renal H(2)O(2) production, and the expression of oxidant and antioxidant enzymes in young (1<em>3</em> weeks) and old (52 weeks) male Wistar Kyoto (WKY) rats. Urinary lipid peroxidation levels and H(2)O(2) production by the renal cortex and medulla of old rats were higher than their young counterparts. This was accompanied by overexpression of NADPH oxidase components Nox4 and p22(phox) in the renal cortex of old rats. Similarly, expression of superoxide dismutase (<em>SOD</em>) isoforms 2 and <em>3</em> and catalase were increased in the renal cortex from old rats. Renal function parameters (creatinine clearance and fractional excretion of sodium), diastolic blood pressure and heart rate were not affected by aging, although slight increases in systolic blood pressure were observed during this 52-week period. It is concluded that overexpression of renal Nox4 and p22(phox) and the increases in renal H(2)O(2) levels in aged WKY does not associate with renal functional impairment or marked increases in blood pressure. It is hypothesized that lack of oxidative stress-associated effects in aged WKY rats may result from increases in antioxidant defenses that counteract the damaging effects of H(2)O(2).

OBJECTIVE

Prolonged controlled mechanical ventilation (MV) is known to induce diaphragmatic oxidative stress that seems to be an important factor reducing force-generating capacity. To better understand the cellular mechanisms involved, this work examined the effect of short vs. prolonged MV on antioxidant defense in the diaphragm.

METHODS

Prospective, randomized, controlled animal study in a university laboratory.

METHODS

Eleven piglets (15-20 kg) were assigned to one of two groups: a long-MV group (n=6) ventilated for <em>3</em> days or a short-MV group (n=5) ventilated for <em>3</em> h. Force frequency curves of the transdiaphragmatic pressure (Pdi) were obtained in vivo by phrenic nerve pacing. Oxidative stress was evaluated by thiobarbituric reactive substance (TBARs) content and the enzymatic antioxidant activity of both superoxide dismutase (<em>SOD</em>) and glutathione peroxidase (GPx) in samples of diaphragm.

RESULTS

Pdi decreased in the long-MV group by <em>3</em>0-<em>3</em>5% over the <em>3</em> days at all frequencies compared to the short-MV group. Diaphragm TBARs content was significantly higher and <em>SOD</em> activity lower in long-MV animals than in short-MV animals after 72 h. GPx activity tended to be lower in diaphragms from long-MV animals, but this difference was not significant.

CONCLUSIONS

This study shows that <em>3</em> days of MV in piglets is associated with a decrease in antioxidant activity which could emphasize oxidative stress and both contribute to the diaphragm dysfunction caused by MV.

Using <em>3</em>0 anesthetized cats, we examined whether oxygen radicals produce airway constriction or hyperresponsiveness. In one group, we administered aerosolized xanthine (0.1%) for <em>3</em> min followed by aerosolized xanthine oxidase (XO) (1 U/ml) for 5 min in order to generate oxygen radicals enzymatically in the airways. Pulmonary resistance (RL) instantaneously increased from 14.8 +/- 0.9 to <em>3</em>0.8 +/- 1.4 cm H2O/L/s (p less than 0.01). The increase in RL was significantly depressed by prior administration of polyethylene glycol-superoxide dismutase (PEG-<em>SOD</em>) or polyethylene glycolcatalase (PEG-CAT). In a second group, in order to examine changes in airway responsiveness, we studied acetylcholine (ACh) challenge before and <em>3</em>0, 60, and 120 min after inhalations of xanthine and XO. After xanthine-XO, the airways were hyperresponsive to ACh at <em>3</em>0 and at 60 min (p less than 0.05) but not at 120 min. The geometric means of ACh provocative concentrations that caused an increase in RL of 10 cm H2O/L/s above the baseline value before and <em>3</em>0, 60, and 120 min after xanthine-XO were 0.25, 0.045, 0.07<em>3</em>, and 0.15%, respectively. The increase in responsiveness to ACh was significantly correlated with the increase in RL after xanthine-XO inhalation (r = 0.88, p less than 0.05). These data support the concept that oxygen radicals generated by xanthine-XO inhalation may induce bronchoconstriction and airway hyperresponsiveness.

The mechanism by which the bcl-2 oncogene exerts its anti-apoptotic and antioxidant action is unknown. We found that expression of bcl-2 in superoxide dismutase-deficient (<em>SOD</em>-) Escherichia coli resulted in increased transcription of the KatG catalase-peroxidase, a 1<em>3</em>-fold increase in KatG activity and a 100-fold increase in resistance to hydrogen peroxide. In addition, mutation rate was increased <em>3</em>-fold, and katG and oxyR, a transcriptional regulator of katG induction, were required for aerobic survival. These data indicate that Bcl-2 acts as a pro-oxidant in E. coli, i.e. Bcl-2 generates reactive oxygen intermediates. In support of a pro-oxidant mechanism in eukaryotic cells, we found a 7<em>3</em>% increase in superoxide dismutase activity in a murine B-cell line overexpressing Bcl-2. Increases in reduced glutathione and in oxyradical damage to DNA, previously observed in other overexpressing cell lines, are additional evidence for a pro-oxidant mechanism. Thus, Bcl-2 does not appear to be an antioxidant. Instead, Bcl-2 appears to influence levels of reactive oxygen intermediates that induce endogenous cellular antioxidants. This activity of Bcl-2 may control entry into apoptosis.

Renal injury is a common pathophysiological feature in women with preeclampsia as evidenced by increased protein leakage (proteinuria) and glomerular injury (glomerular endotheliosis). Recently, podocyturia was found in preeclampsia, suggesting podocyte shedding occurs in this pregnancy disorder. However, podocyte function in preeclampsia is poorly understood. In this study, the authors have examined podocyte-specific protein expressions for nephrin, glomerular epithelial protein 1 (GLEPP-1), and ezrin in kidney biopsy tissue sections from women with preeclampsia. Expressions for vascular endothelial growth factor (VEGF) and its receptor Flt-1 and oxidative stress marker nitrotyrosine and antioxidant CuZn-superoxide dismutase (CuZn-<em>SOD</em>) were also examined. Kidney tissue sections from nonhypertensive and chronic hypertensive participants were stained as controls. The findings were (1) nephrin and GLEPP-1 were mainly expressed in glomerular podocytes; (2) ezrin was expressed in both glomerular podocytes and tubular epithelial cells; (<em>3</em>) compared to tissue sections from nonhypertensive and chronic hypertensive participants, nephrin and GLEPP-1 expressions were much reduced in tissue sections from preeclampsia and ezrin expression was reduced in podocytes; (4) enhanced VEGF, Flt-1, and nitrotyrosine, but reduced CuZn-<em>SOD</em>, expressions were observed in both glomerular podocytes and endothelial cells in tissue sections from preeclampsia; and (5) the expression pattern for nephrin, GLEPP-1, ezrin, VEGF, Flt-1, and CuZn-<em>SOD</em> were similar between tissue sections from nonhypertensive and chronic hypertensive participants. Although the authors could not conclude from this biopsy study whether the podocyte injury is the cause or effect of the preeclampsia phenotype, the data provide compelling evidence that podocyte injury accompanied by altered angiogenesis process and increased oxidative stress occurs in kidney of patients with preeclampsia.

1. The influence of hydroquinone on relaxations induced by nitric oxide (NO), nitrovasodilator drugs, and non-adrenergic, non-cholinergic (NANC) field stimulation has been investigated in three tissues in which endogenous nitrates have been implicated in the NANC response; the mechanism of action of hydroquinone was also studied. 2. In mouse anococcygeus, hydroquinone (10-100 microM) produced a concentration-dependent inhibition of relaxations induced by 15 microM NO. Hydroquinone, 100 microM, which reduced responses to NO by 85%, had no effect on relaxations induced by NANC field stimulation (10 Hz; 20s trains), hydroxylamine (10 microM), sodium nitroprusside (1 microM) or sodium azide (20 microM). <em>3</em>. In guinea-pig trachea, 100 microM hydroquinone reduced relaxations to 150 microM NO by 75%, but had no effect on those to NANC stimulation (10 Hz; <em>3</em>0 s trains) or sodium azide (5 microM). 4. In rat gastric fundus, 100 microM hydroquinone reduced relaxations to 1 microM NO by 85%, but had no effect on those to NANC stimulation (0.5 Hz; 15 s trains) or sodium azide (2 microM). 5. Superoxide dismutase (<em>SOD</em>; 50 u ml-1) had no effect on relaxations of the mouse anococcygeus in response to 15 microM NO or 10 Hz NANC stimulation. Further, the inhibition of responses to NO by hydroquinone was unaffected in the presence of <em>SOD</em>. 6. Hydroquinone (10-100 microM) failed to generate superoxide anions, as detected by a chemiluminescent assay. However, 100 microM hydroquinone, like <em>SOD</em> (50 u ml-1), produced almost complete inhibition of superoxide anion chemiluminescence induced by xanthine (500 microM): xanthine oxidase (0.07 u ml-1). 7. It is concluded that, in our system, hydroquinone inhibits NO by acting as a free radical scavenger rather than by generating superoxide anions. The ability of hydroquinone to block relaxations to NO, but not NANC stimulation, may suggest that the endogenous nitrate substance released by these NANC nerves may not be free NO, but may be an NO-containing, or NO-generating, molecule.

Reactive oxygen species (ROS) have been implicated in the pathogenesis of cerebral injury after ischemia-reperfusion (I/R). Fish n-<em>3</em> essential fatty acids (EFA), contain eicosapentaenoic acids (EPA) and docosahexoenoic acids (DHA), exhibit antioxidant properties. DHA is an important component of brain membrane phospholipids and is necessary for the continuity of neuronal functions. EPA prevents platelet aggregation and inhibits the conversion of arachidonic acid into thromboxane A(2) and prostaglandins. They have been suggested to be protective agents against neurological and neuropsychiatric disorders. In this study, the neuroprotective effects of fish n-<em>3</em> EFA on oxidant-antioxidant systems and number of apoptotic neurons of the hippocampal formation (HF) subjected to cerebral I/R injury was investigated in Sprague-Dawley rats. Six rats were used as control (Group I). Cerebral ischemia was produced by occlusion of both the common carotid arteries combined with hypotension for 45 min, followed by reperfusion for <em>3</em>0 min, in rats either on a standard diet (Group II) or a standard diet plus fish n-<em>3</em> EFA (Marincap((R)), 0.4 g/kg/day, by gavage) for 14 days (Group III). At the end of procedures, the rats were sacrificed and their brains were removed immediately. The levels of malonedialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (<em>SOD</em>) and catalase (CAT) were measured in left HF. In addition, the number of apoptotic neurons was counted by terminal transferase dUTP nick end labelling (TUNEL) assay in histological samples of the right HF. We found that <em>SOD</em> activities and MDA levels increased in Group III rats compared with Group II rats. On the other hand, CAT activities and NO levels were found to be decreased in Group III rats compared with Group II rats. Additionally, the number of apoptotic neurons was lower in Group III in comparison with Group II rats. The present findings suggest that fish n-<em>3</em> EFA could decrease the oxidative status and apoptotic changes in ischemic rat hippocampal formation. Dietary supplementation of n-<em>3</em> EFA may be beneficial to preserve or ameliorate ischemic cerebral vascular disease.

Reactive oxygen metabolites have been implicated as important mediators of inflammation-induced intestinal injury associated with ischemia (and reperfusion), radiation, and inflammatory bowel disease. Because the colonic mucosa may be subjected to significant oxidant stress during times of acute and chronic inflammation, knowledge of the oxidant defense mechanisms in the colon is of biologic and potential clinical importance. Therefore, the objective of this study was to quantify the specific activities of superoxide dismutase (<em>SOD</em>), catalase, and GSH peroxidase in the normal human colon. We found low, but significant, amounts of all three enzymes in the mucosa, submucosa, and muscularis/serosa of the human colon. However, the mucosal, levels of <em>SOD</em> (<em>3</em>.6 +/- 0.<em>3</em> units/mg protein), catalase (11 +/- <em>3</em> units/mg), and GSH peroxidase (15.2 +/- 0.8 mU/mg) represented only 8%, 4%, and 40%, respectively, of those values determined for human liver. Colonic epithelial cells derived from mucosal biopsies exhibited significantly higher specific activities for <em>SOD</em> (12 +/- 0.5 units/mg) and catalase (26 +/- 6 units/mg) when compared to whole mucosa, suggesting most of the mucosal activity was associated with the epithelial cells and not the lamina propria. In a comparative study, we found that a human colonic carcinoma cell line (CaCo-2) contained significantly lower <em>SOD</em> (6 +/- 0.5 units/mg) and catalase (6 +/- 0.6 units/mg) activities when compared to colonic epithelial cells. Taken together, our data suggest that: (1) the colonic mucosa is relatively deficient in antioxidant enzymes when compared to liver, and (2) most of the protective enzyme activity is localized within the epithelium and not the mucosal interstitium.

OBJECTIVE

Oxidized low-density lipoprotein (oxLDL) modulates intracellular redox status and induces apoptosis in endothelial cells. However, the signal pathways and molecular mechanism remain unknown. In this study, we investigated the role of manganese superoxide dismutase (Mn-SOD) on oxLDL-induced apoptosis via c-Jun NH2-terminal kinase (JNK)-mediated ubiquitin/proteasome pathway.

RESULTS

OxLDL induced JNK phosphorylation that peaked at 30 minutes in human aortic endothelial cells. Fluorescence-activated cell sorting analysis revealed that oxLDL increased mitochondrial superoxide production by 1.88+/-0.19-fold and mitochondrial membrane potential by 18%. JNK small interference RNA (siJNK) reduced oxLDL-induced mitochondrial superoxide production by 88.4% and mitochondrial membrane potential by 61.7%. OxLDL did not affect Mn-SOD mRNA expression, but it significantly reduced Mn-SOD protein level, which was restored by siJNK. Immunoprecipitation by ubiquitin antibody revealed that oxLDL increased ubiquitination of Mn-SOD, which was inhibited by siJNK. OxLDL-induced caspase-3 activities were also attenuated by siJNK but were enhanced by Mn-SOD small interfering RNA. Furthermore, overexpression of Mn-SOD abrogated oxLDL-induced caspase-3 activities.

CONCLUSIONS

OxLDL-induced JNK activation regulates mitochondrial redox status and Mn-SOD protein degradation via JNK-dependent ubiquitination, leading to endothelial cell apoptosis.

Point mutations of Cu,Zn-superoxide dismutase (Cu,Zn-<em>SOD</em>) have been linked to familial amyotrophic lateral sclerosis (FALS). We reported that Cu,Zn-<em>SOD</em> can catalyze free radical generation and a FALS mutant, G9<em>3</em>A, exhibits an enhanced free radical-generating activity, while its dismutation activity is identical to that of the wild-type enzyme (Yim, M. B., Kang, J.-H., Yim, H.-S., Kwak, H.-S., Chock, P. B., and Stadtman, E. R. (1996) Proc. Natl. Acad. Sci. U. S. A. 9<em>3</em>, 5709-5714). The A4V mutation is both the most commonly detected of FALS-associated <em>SOD</em>1 mutations and among the most clinically severe (Rosen, D. R., Bowling, A. C., Patterson, D., Usdin, T. B., Sapp, P., Mezey, E., McKenna-Yasek, D., O'Regan, J. P., Rahmani, Z., Ferrante, R. J., Brownstein, M. J., Kowall, N. W., Beal, M. F., Horvitz, H. R., and Brown, R. H., Jr. (1994) Hum. Mol. Genet. <em>3</em>, 981-987). We cloned the cDNA for the FALS A4V mutant, overexpressed the protein in Sf9 insect cells, purified the protein, and studied its enzymic activities. Our results show that the mutant and wild-type enzymes contain one copper ion per subunit and have identical dismutation activities. However, the free radical-generating activity of the mutant, as measured by the spin trapping method at low H2O2 concentration, is enhanced relative to that of the wild-type and G9<em>3</em>A enzyme (wild-type < G9<em>3</em>A < A4V). This is due to the decrease in the Km value for H2O2, wild-type>> G9<em>3</em>A>> A4V, while the kcat is identical for these enzymes. Thus, the FALS symptoms are not associated with the reduction in the dismutation activity of the mutant enzyme. The fact that the A4V mutant has the lowest Km for H2O2 is correlated to the clinical severity observed with the A4V patients, if FALS is associated with a differential gain of the free radical-generating function of the Cu,Zn-<em>SOD</em> mutant.

Traffic is a major source of particulate matter (PM), and ultrafine particulates and traffic intensity probably contribute significantly to PM-related health effects. As a strong relationship between air pollution and motor vehicle-originated pollutants has been shown to exist, air pollution genotoxicity studies of urban cities are steadily increasing. In Korea, the death rate caused by lung cancer is the most rapidly increased cancer death rate in the past 10 years. In this study, genotoxicity of PM2.5 (<2.5μm in aerodynamic diameter particles) collected from the traffic area in Suwon City, Korea, was studied using cultured human lung bronchial epithelial cells (BEAS-2B) as a model system for the potential inhalation health effects. Organic extract of PM2.5 (CE) generated significant DNA breakage and micronucleus formation in a dose-dependent manner (1μg/cm(<em>3</em>)-50μg/cm(<em>3</em>)). In the acid-base-neutral fractionation of PM2.5, neutral samples including the aliphatic (F<em>3</em>), aromatic (F4) and slightly polar (F5) fractions generated significant DNA breakage and micronucleus formation. These genotoxic effects were significantly blocked by scavenging agents [superoxide dismutase (<em>SOD</em>), sodium selenite (SS), mannitol (M), catalase (CAT)]. In addition, in the modified Comet assay using endonucleases (FPG and ENDOIII), CE and its fractions (F<em>3</em>, F4, and F5) increased DNA breakage compared with control groups, indicating that CE and fractions of PM2.5 induced oxidative DNA damage. These results clearly suggest that PM2.5 collected in the Suwon traffic area has genotoxic effects and that reactive oxygen species may play a distinct role in these effects. In addition, aliphatic/chlorinated hydrocarbons, PAH/alkylderivatives, and nitro-PAH/ketones/quinones may be important causative agents of the genotoxic effects.

The mitogen-activated protein kinase (MAPK) pathways and insulin-like signaling play pivotal roles in cellular stress response. Using an anti-phospho-SAPK/JNK antibody and a daf-16::GFP-based reporter assay, the present study shows in Caenorhabditis elegans that ambient temperature (1-<em>3</em>7 degrees C) specifically influences the activation (phosphorylation) of the MAP kinase JNK-1 as well as the nuclear translocation of DAF-16, the main downstream target of insulin-like signaling. Activated JNK-1 was detected only in neuronal cells, and JNK-1 was found to be controlled by the MAPK JKK-1 under heat stress. Comparative analyses on the wildtype and a jnk-1 deletion mutant revealed a promoting influence of JNK-1 on both nuclear DAF-16 translocations and DAF-16 target gene (superoxide dismutase <em>3</em>, <em>sod</em>-<em>3</em>) expressions within peripheral, non-neuronal tissue. Consequently, the mutant exhibited a reduced thermal tolerance and reproductive fitness at higher temperatures. These results provide evidence of indirect interactions between neuronal MAPK and peripheral insulin-like signaling in response to environmental stimuli (temperature, H2O2).

Increased expression of mac25/insulin-like growth factor binding-protein related protein-1 (IGFBP-rP1) in human breast and prostate epithelial cell lines results in the suppression of tumor growth. CDNA expression array analysis revealed increased manganese superoxide dismutase (<em>SOD</em>-2) expression in the mac25/IGFBP-rP1-transfected M12 human prostate cancer cell line compared to M12 control cells. <em>SOD</em>-2 has been postulated to be a tumor suppressor. <em>SOD</em>-2 was also increased in LNCaP cells stably transfected with mac25/IGFBP-rP1, but not in mac25/IGFBP-rP1-transfected PC-<em>3</em> cells. Mac25 LNCaP cells had a marked decrease in tumor growth in nude mice compared to controls, but there was no difference in tumor growth in mac25 PC-<em>3</em> cells compared to control. Phosphorylated Erk and Akt were increased in the M12 and LNCaP transfected mac25/IGFBP-rP1 cells but not PC-<em>3</em> mac25. Inhibition of PI-<em>3</em> kinase results in a marked decrease in viability of the M12-mac25 cells compared to M12 controls. Cells treated with H(2)O(2) result in an increase in phospho-ERK. Transfection of <em>SOD</em>-2 in M12 cells markedly decreased tumor growth, apoptosis, G1 delay in the cell cycle, and expression of senescence associated beta-galactosidase. These results suggest that one of the downstream mediators of the senescence-associated tumor suppression effect of mac25/IGFBP-rP1 is <em>SOD</em>-2.

Oxidative stress and chronic inflammation are important features in the pathogenesis of chronic obstructive pulmonary disease (COPD). Oxidative stress has important consequences for several elements of lung physiology and for the pathogenesis of COPD, including oxidative inactivation of antiproteases and surfactants, mucus hypersecretion, membrane lipid peroxidation, alveolar epithelial injury, remodeling of extracellular matrix, and apoptosis. Therefore, targeting oxidative stress with antioxidants or boosting the endogenous levels of antioxidants is likely to be beneficial in the treatment of COPD. Antioxidant and/or anti-inflammatory agents such as thiol molecules (glutathione and mucolytic drugs, such as N-acetyl-L-cysteine and N-acystelyn), dietary polyphenol (curcumin-diferuloylmethane, a principal component of turmeric), resveratrol (a flavanoid found in red wine), green tea (theophylline and epigallocatechin-<em>3</em>- gallate), ergothioneine (xanthine and peroxynitrite inhibitor), quercetin, erdosteine and carbocysteine lysine salt, have been reported to control NF-kappaB activation, regulation of glutathione biosynthesis genes, chromatin remodeling and hence inflammatory gene expression. Specific spin traps such as alpha-phenyl-N-tert-butyl nitrone, a catalytic antioxidant (EC<em>SOD</em> mimetic), manganese (III) meso-tetrakis (N,N'-diethyl-1,<em>3</em>-imidazolium-2-yl) porphyrin (AEOL 10150 and AEOL 1011<em>3</em>), and a <em>SOD</em> mimetic M40419 have also been reported to inhibit cigarette smoke-induced inflammatory responses in vivo. Since a variety of oxidants, free radicals and aldehydes are implicated in the pathogenesis of COPD it is possible that therapeutic administration of multiple antioxidants will be effective in the treatment of COPD. Various approaches to enhance lung antioxidant capacity and clinical trials of antioxidant compounds in COPD are discussed.

Reactive oxygen species (ROS) production is a normal process of cell metabolism. In vitro environments usually increase cell production of ROS, which has been implicated as a main cause of cell damage. Nevertheless, the role of ROS in oocyte in vitro maturation (IVM) is controversial. In most cells, enzymatic antioxidant systems can attenuate the effect of oxidative stress by scavenging ROS. The aim of this work was to determine whether: (1) standard conditions of bovine oocyte IVM are responsible for oxidative stress; (2) cumulus cells participate in protection against oxidative stress of the oocyte; and (<em>3</em>) enzymatic antioxidant activity is present in oocytes and cumulus cells. Cumulus-oocyte complexes (COCs) were matured in TCM-199 + 10% steer serum for 24 h at <em>3</em>9 degrees C in 5% CO2:95% humidified air. Oxidative stress was determined by the 2',7'-dichlorofluorescein diacetate assay. Superoxide dismutase (<em>SOD</em>), glutathione peroxidase, and catalase activities were measured spectrophotometrically. Under standard conditions of in vitro maturation, there was no increase in ROS production per COC (P>> 0.05), but ROS level per cumulus cell diminished. There was no modification in ROS levels in oocytes matured in the presence versus the absence of their surrounding cumulus cells ( P>> 0.05). To the best of our knowledge, the presence of <em>SOD</em>, glutathione peroxidase and catalase activities were detected in oocytes and cumulus cells for the first time. Enzymatic units were lower in denuded oocytes with respect to cumulus (P < 0.05), accounting for <em>3</em>7% for <em>SOD</em>, 25% for glutathione peroxidase, and 11% for catalase of the total COC units. Specific enzyme activity diminished in cumulus cells (P>> 0.05) and increased in oocytes due to maturation (P>> 0.05). The presence of activity of an enzymatic antioxidant system in the bovine oocyte would regulate in part ROS levels during IVM. Oocytes could be capable of controlling the increase in ROS because of the presence of their own enzymatic antioxidant system, <em>SOD</em> having the highest specific activity with respect to cumulus cells.

To determine the interrelationship between the hydrogen peroxide (H(2)O(2)) mediated killing and the potential role of bacterial catalase and <em>SOD</em> in the evasion of host defense, we examined three clinical isolates of Staphylococcus aureus and evaluated their intracellular survival mechanism within murine peritoneal macrophages. Fluorescent microscopy and bacterial colony-forming unit (cfu) count revealed that phagocytic capacity of murine peritoneal macrophages was highest after 2h of in vitro infection with S. aureus. To understand whether catalase and <em>SOD</em> contributing in the intracellular survival, were of bacterial origin or not, <em>3</em> amino 1,2,4 triazole (ATZ) and Diethyldithiocarbamic acid (DDC) were used to inhibit specifically macrophage derived catalase and <em>SOD</em> respectively. Catalase activity from the whole staphylococcal cell in presence of ATZ suggested that the released catalase were of extracellular origin. Scanning electron microscopy revealed the degraded host cell membrane integrity during prolonged infection. Purified bacterial catalase from the intracellularly survived S. aureus recovered after 5h of infection and its inhibition by ATZ in the zymography strengthened the scope of involvement of these anti-oxidants in the intracellular survival of S. aureus.

Pistachio (Pistacia vera L.; Anacardiaceae) is native of aride zones of Central and West Asia and distributed throughout the Mediterranean basin. In Italy, a pistachio cultivar of high quality is typical of Bronte (Sicily), an area around the Etna volcano, where the lava land and climate allow the production of a nut with intense green colour and aromatic taste, very appreciated in international markets. Pistachio nuts are a rich source of phenolic compounds, and have recently been ranked among the first 50 food products highest in antioxidant potential. Pistachio nuts are often used after removing the skin, which thus represents a significant by-product of pistachio industrial processing. The present study was carried out to better characterize the phenolic composition and the antioxidant activity of Bronte pistachios, with the particular aim to evaluate the differences between pistachio seeds and skins. The total content of phenolic compounds in pistachios was shown to be significantly higher in skins than in seeds. By HPLC analysis, gallic acid, catechin, eriodictyol-7-O-glucoside, naringenin-7-O-neohesperidoside, quercetin-<em>3</em>-O-rutinoside and eriodictyol were found both in pistachio seeds than in skins; furthermore, genistein-7-O-glucoside, genistein, daidzein and apigenin appeared to be present only in pistachio seeds, while epicatechin, quercetin, naringenin, luteolin, kaempferol, cyanidin-<em>3</em>-O-galactoside and cyanidin-<em>3</em>-O-glucoside are contained only in pistachio skins. The antioxidant activity of pistachio seeds and skins were determined by means of four different assays (DPPH assay, Folin-Ciocalteau colorimetric method and TEAC assay, <em>SOD</em>-mimetic assay). As expected on the basis of the chemical analyses, pistachio skins have shown to possess a better activity with respect to seeds in all tests. The excellent antioxidant activity of pistachio skins can be explained by its higher content of antioxidant phenolic compounds. By HPLC-TLC analysis, gallic acid, catechin, cyanidin-<em>3</em>-O-galactoside, eriodictyol-7-O-glucoside and epicatechin appeared to be responsible for the antioxidant activity of pistachio skin, together with other unidentified compounds. In conclusion, our work has contributed to clarify some particular characteristics of Bronte pistachios and the specific antioxidant power of pistachio skins. Introduction of pistachios in daily diet may be of undoubted utility to protect human health and well-being against cancer, inflammatory diseases, cardiovascular pathologies and, more generally, pathological conditions related to free radical overproduction. On the other hand, pistachio skins could be successfully employed in food, cosmetic and pharmaceutical industry.

OBJECTIVE

Fatty acid (FA) composition of the spermatozoa may be an important determinant of fertility. The aim was to evaluate polyunsaturated fatty acid (PUFA) composition of the blood plasma and spermatozoa in infertile men with idiopathic oligoasthenoteratozoospermia (OAT).

METHODS

Eighty-two infertile men with idiopathic OAT and seventy-eight fertile men defined according to semen concentration and proven fertility were enrolled in the study. The semen parameters were assessed according to World Health Organization criteria; three omega-<em>3</em> fatty acids--alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and two omega-6 fatty acids--linoleic acid (LA) and arachidonic acid (AA) concentrations were measured in blood plasma and spermatozoa; and the seminal plasma enzymatic antioxidant levels of catalase, and superoxide dismutase (<em>SOD</em>) were also assessed.

RESULTS

Proven fertile men had higher blood and spermatozoa levels of omega-<em>3</em> FAs compared with the infertile patients. The ratio of serum omega-6/omega-<em>3</em> fatty acids was significantly higher in infertile (14.8+/-4.<em>3</em>) patients compared to fertile controls (6.<em>3</em>+/-2.2) (P=0.001). Additionally, levels of AA were higher and the omega-<em>3</em> index (EPA+DHA) was lower in infertile subjects than in fertile controls (all P values<0.05). Infertile men had higher mean AA:DHA ratio and AA:EPA (6.4+/-2.9 and 12.0+/-4.9, respectively) than fertile men (<em>3</em>.<em>3</em>+/-1.8 and 6.7+/-2.6, respectively) (both P=0.001). A strong negative correlation was found between the AA:DHA and AA:EPA ratios and total sperm count (r=-0.62, P=0.001 and r=-0.64, P=0.001, respectively), sperm motility (r=-0.6<em>3</em>, P=0.001 and r=-0.61, P=0.001, respectively), and sperm morphology (r=-0.61, P=0.001, and r=-0.59, P=0.002, respectively).

CONCLUSIONS

Infertile men had lower concentrations of omega-<em>3</em> FAs in spermatozoa than fertile men. These results suggest that research should be performed to assess the potential benefits of omega-<em>3</em> FA supplementation as a therapeutic approach in infertile men with idiopathic OAT.