Cu-Zn SOD Research Articles

Dietary nitrate protects submandibular gland from hyposalivation in ovariectomized rats via suppressing cell apoptosis

Xerostomia, a major oral symptom of menopause, is a subjective feeling of dry mouth associated with oral pain and difficulties in deglutition and speech, which significantly reduces patient's quality of life. Dietary nitrate, which can be converted to nitric oxide, has multiple physiological functions in the body, including antioxidant activity and vasodilatation; however, its protective effect against xerostomia remains poorly understood. The present study aimed to evaluate the effects of dietary nitrate on estrogen deficiency-induced xerostomia. We established an ovariectomized (OVX) rat model, which included five groups: sham-operated, OVX, OVX + 0.4 mM nitrate, OVX + 2 mM nitrate, and OVX + 4 mM nitrate (n = 6). After ovariectomy, animals in the nitrate treatment groups received appropriate amounts of sodium nitrate dissolved in distilled water for 3 months. The results showed that nitrate treatment reduced body weight and water intake, and increased serum nitrate and nitrite levels. Furthermore, nitrate uptake increased saliva secretion as evidenced by saliva flow rates and aquaporin 5 expression, and alleviated histological lesions as evidenced by reduction of the fibrotic area and cell atrophy in the salivary glands. Although protective effects of nitrate against estrogen deficiency-induced xerostomia were observed at all doses, treatment with 2 mM nitrate was more effective than that with 0.4 mM and 4 mM nitrate. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and caspase-3 expression analyses showed that nitrate also protected cells from apoptosis, possibly through upregulation of Cu-Zn superoxide dismutase (Cu-Zn SOD) known to inhibit oxidative stress-related apoptosis. Our findings indicate that nitrate could improve functional activity of the salivary glands in OVX rats by suppressing apoptosis and upregulating Cu-Zn SOD expression, suggesting that dietary nitrate may potentially prevent hyposalivation in menopausal women.

Overexpression of Cu-Zn SOD in Brucella abortus suppresses bacterial intracellular replication via down-regulation of Sar1 activity.

Brucella Cu-Zn superoxide dismutase (Cu-Zn SOD) is a periplasmic protein, and immunization of mice with recombinant Cu-Zn SOD protein confers protection against Brucella abortus infection. However, the role of Cu-Zn SOD during the process of Brucella infection remains unknown. Here, we report that Cu-Zn SOD is secreted into culture medium and is translocated into host cells independent of type IV secretion systems (T4SS). Furthermore, co-immunoprecipitation and immunofluorescence studies reveal that Brucella abortus Cu-Zn SOD interacts with the small GTPase Sar1. Overexpression of Cu-Zn SOD in Brucella abortus inhibits bacterial intracellular growth by abolishing Sar1 activity in a manner independent of reactive oxygen species (ROS) production.

Comparison of copper bioavailability in copper-methionine, nano-copper oxide and copper sulfate additives in the diet of Russian sturgeon Acipenser gueldenstaedtii

This study was conducted to evaluate the relative bioavailability of copper sulfate (CuSO4), copper-methionine (CuMet) and nano‑copper oxide (CuONano) as a diet additive by comparing growth, Cu status, antioxidant activity, immune response and Cu apparent digestibility in Russian sturgeon Acipenser gueldenstaedtii. The control was a semi-purified basal diet without Cu supplementation and the experimental diets were prepared with the forms of CuSO4, CuMet and CuONano, representatively. The Cu contents were 2, 4, 6, 8 and 16mg/kg in the CuMet and CuONano diet groups, and 4, 6 and 16mg/kg in the CuSO4 diet groups. Sturgeon (9.82±0.08g) were fed with the control diet and 13 experimental diets with Cu in different contents and sources for 8weeks. The bacterial challenge test and Cu apparent digestibility determination were carried out at the end. The highest weight gain (WG), whole body Cu concentration, Cu apparent digestibility, copper‑zinc superoxide dismutase (Cu-Zn SOD) activity, total antioxidant capacity, lysozyme and immunoglobulin M content were achieved at 6mg Cu/kg in the CuSO4 diet, and 4mg Cu/kg in both CuMet and CuONano diets. Sturgeon fed 4mg Cu/kg in the CuMet diet or the CuONano diet had higher growth rate, tissue Cu deposition, antioxidant and immune capacity than fish fed the same Cu content in the CuSO4 diet. At the same time, Cu in the CuMet or CuONano diet exhibited higher apparent digestibility and Aeromonas hydrophila resistance. When the Cu content was standardized in the form of CuSO4, the relative Cu bioavailability was 153% - 168% in the CuMet diet and 172% - 202% in the CuONano diet based on weight gain, hepatic CuZn SOD activity, and whole body Cu concentrations. The optimal dietary Cu requirements was about 5mg/kg when CuMet or CuONano was used, and increased to 8mg/kg when CuSO4 was used. This study indicates that Cu in the forms of CuMet and CuONano is 1.5–2 times more bioavailable than in the form of CuSO4 for the dietary Cu requirements of Russian sturgeon.

P 201 - Role of redox-potential decreasing in the chronic isoproterenol-induced cardiac hypertrophy and its pharmacological correction

This study investigated the efficacy of preventive role of NAD-containing cardiotrophic drug Adenocine® in chronic isopreterenol (ISO)-induced cardiac hypertrophy (CH) on tissue antioxidant status. On the 14 days of ISO-induced CH (10 mg/kg daily ) all male chinchilla rabbits were randomly assigned into 3 groups: control - infusion of 0,9% NaCl; main I - receive 10 mg/kg nebivolol per os in combination with lisinopril (10 mg/kg) infusion (traditional treatment (TT)); and main II - receive intravenously 15 mg/kg of Adenocin dissolved in water for injection during 7 days. The increases of heart weight by 18,6% and heart-to-body weight ratio by 35,5% observed in CH were significantly suppressed in Adenocin-treated group by 15,8 and 31,5% and only by 6,4 and 9,7% respectively after TT. ISO-induced CH is associated with loss of NAD from 6,4±0,3 to 5,1±0,4mMol/mg. TT didn’t cause the restoration NAD/NADH and NAD content in LV myocardium and decrease level of BNP. Adenocin treatment restored the normal level of NAD+/NADH, increased the activity of CuZn–SOD, Mn–SOD,superoxide anion production, catalase activities and decreased the content of MDA while the TT did not. Conclusion The results described the benficial cardioprotective effect of Adenocin on the the activities of both enzymatic and non-enzymatic antioxidants LV myocardium of ISO-induced CHF.

Effects of Copper on Hemocyte Apoptosis, ROS Production, and Gene Expression in White Shrimp Litopenaeus vannamei.

Copper, a common chemical contaminant in aquatic environment, is known to be toxic to aquatic life at high concentrations. In the present study, we evaluated the apoptotic cell ratio and ROS production in hemocytes of the white shrimp Litopenaeus vannamei exposed to 1 or 5mgL-1 Cu for 0, 3, 6, 12, 24, and 48h. The expression changes of antioxidant biomarker genes, i.e., copper-zinc superoxide dismutase (Cu-Zn SOD) and catalase (CAT), apoptosis-related genes, i.e., caspase-3 and inhibitor of apoptosis protein (IAP), and a specific biomarker gene of heavy metal pollution, i.e., metallothionein (MT), were also determined in hemocytes. Significant increases in ROS production were observed in both treatment groups at each time points. The apoptotic cell ratios were significantly increased at 6-48h among shrimp exposed to 1mgL-1 Cu and at each time points in 5mgL-1 Cu group. These results indicated that Cu would induce oxidative stress and apoptosis in the hemocyte of L. vannamei. Quantitative real-time PCR analysis revealed that the relative expression levels of Cu-Zn SOD, CAT, caspase-3, IAP, and MT were upregulated in a dose-dependent and time-dependent manner, suggesting the involvement of these genes in stress response against Cu exposure.

Effects of Weight Reduction After Sleeve Gastrectomy on Metabolic Variables in Saudi Obese Subjects in Aseer Province of Kingdom of Saudi Arabia.

The objectives of this study were to investigate the occurrence of oxidative stress, status of protective antioxidants enzymes, inflammatory biomarkers, and some metabolic health variables in the blood and to compare the results between those of the normal controls and obese patients submitted to sleeve gastrectomy-induced weight loss over a 1-year follow-up period. A prospective study was conducted in Aseer Central Hospital and Abha Private Hospital in the Kingdom of Saudi Arabia from January 2012 to January 2013 on 50 normal (BMI=22-25kg/m2) control subjects and 50 obese (BMI=45-50kg/m2) patients. A subset of 20 men and 80 women patients, aged 20-45years, was included. The systemic blood cell counts were determined by Beckman Coulter UniCel analyzer. The occurrence of oxidative stress, the status of antioxidant enzyme system in the blood, levels of serum hepatic enzymes, cardiovascular risk factors, and serum sodium, potassium, copper, and zinc levels were determined by spectrophotometric procedures. The concentration of TSH and T4 were analyzed by Siemens Immunoassay System. Group 1 (Obese: preoperative) This group compared with the normal controls exhibited significant (p<0.05) increase in inflammatory biomarkers, a significant (p<0.05) rise in hepatic enzymes, a significant (p<0.05) decrease in serum total bilirubin. Concentration of serum total cholesterol (TC), triacylglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and fasting blood glucose(FBG) were significantly (p<0.05) increased, but HDL cholesterol (HDL-C) was significantly depleted (p<0.05). Serum urea and creatinine contents were significantly (p<0.05) decreased. Serum copper and zinc levels were significantly (p<0.05) increased. Group 2: Sleeve Gastrectomy Surgery (Obese: postoperative) This group compared with the obese group, preoperatively, demonstrated a profound reduction in body weight (-32%) as well as in BMI (-29%). Serum malondialdehyde, a stress index, was significantly (p<0.001) inhibited and conversely, activities of antioxidant enzymes: superoxide dismutase(Cu-Zn SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PDH), and vitamin C, were remarkably (p<0.001) increased. Furthermore, remarkable improvements in deranged metabolic variables approaching normality were discernible. Inflammatory biomarkers in the blood and hepatic enzymes in serum were significantly (p<0.001) decreased. Levels of TC, TG, LDL-C, FBG, and HDL-C in serum exhibited significant (p<0.05) reductions, a reversal toward normality. Serum albumin and total bilirubin concentrations were significantly increased (p<0.001). Serum sodium, potassium, copper, zinc, and TSH levels were significantly (p<0.001) decreased. Obesity is a chronic disease of multifactorial origin and resulted in perturbations of whole body metabolism in this study. It is thus likely that this imbalance was associated with an inhibition in protective antioxidants and occurrence of oxidative stress. The staging concept of sleeve gastrectomy is a safe and effective approach with remarkable efficacy in sustaining weight loss and bringing back normal metabolism of variables in tissues over a 1-year follow-up period.

Ameliorative Effect of Chlorophyllin on Oxidative Stress in Experimental Model of Diabetes

The aim of this present study was to investigate the effect of chlorophyllin (CHL) on oxidative stress in Streptozotocine (STZ) induced diabetic mice. For the study, mice were divided into Group A: normal control, Group B: diabetic control, Group C: diabetic mice treated with the ascorbic acid, and Group D: diabetic mice treated with CHL. Levels of Reactive Oxygen Species (ROS), lipid peroxidation, protein carbonyl, superoxide dismutase (CuZn SOD &amp;amp;Mn-SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities were examined in kidney and heart tissues of different experimental groups. Histological and ultrastructuralstudies were also carried out to evaluate any changes in tissues as well as sub-cellular organelles. ROS, lipid peroxidation, and protein carbonyl levels have been significantly decreased with concomitant increased of CuZn SOD, Mn-SOD, CAT, GPx, and GR activity in CHLtreated diabetic mice. The histological and ultrastructural studies showed that CHL attenuates the detrimental effect of oxidative stress and alleviated tissue injuries in STZ induced diabetic mice. These results suggested that CHL possesses antioxidative activity and has the potential to amelioratediabetes-associated oxidative stress in mice.

Effects of Zinc Glycinate on Productive and Reproductive Performance, Zinc Concentration and Antioxidant Status in Broiler Breeders.

An experiment was conducted to investigate the effects of zinc glycinate (Zn-Gly) supplementation as an alternative for zinc sulphate (ZnSO4) on productive and reproductive performance, zinc (Zn) concentration and antioxidant status in broiler breeders. Six hundred 39-week-old Lingnan Yellow broiler breeders were randomly assigned to 6 groups consisting of 4 replicates with 25 birds each. Breeders were fed a basal diet (control group, 24mg Zn/kg diet), basal diet supplemented with 80mg Zn/kg diet from ZnSO4 or basal diet supplemented with 20, 40, 60 and 80mg Zn/kg diet from Zn-Gly. The experiment lasted for 8weeks after a 4-week pre-test with the basal diet, respectively. Results showed that Zn supplementation, regardless of sources, improved (P < 0.05) the feed conversion ratio (kilogram of feed/kilogram of egg) and decreased broken egg rate, and elevated (P < 0.05) the qualified chick rate. Compared with the ZnSO4 group, the 80mg Zn/kg Zn-Gly group significantly increased (P < 0.05) average egg weight, fertility, hatchability and qualified chick rate, whereas it decreased (P < 0.05) broken egg rate. The Zn concentrations in liver and muscle were significantly higher (P < 0.05) in 80mg Zn/kg Zn-Gly group than that in ZnSO4 group. Compared with ZnSO4 group, 80mg Zn/kg Zn-Gly group significantly elevated (P < 0.05) the mRNA abundances of metallothionein (MT) and copper-zinc superoxide (Cu-Zn SOD), as well as the Cu-Zn SOD activity and MT concentration in liver. Moreover, the 80mg Zn/kg Zn-Gly group had higher (P < 0.05) serum T-SOD and Cu-Zn SOD activities than that in the ZnSO4 group. This study indicated that supplementation of Zn in basal diet improved productive and reproductive performance, Zn concentration and antioxidant status in broiler breeders, and the 80mg Zn/kg from Zn-Gly was the optimum choice for broiler breeders compared with other levels of Zn from Zn-Gly and 80mg/kg Zn from ZnSO4.

Low Levels of Prohibitin in Substantia Nigra Makes Dopaminergic Neurons Vulnerable in Parkinson's Disease.

Since substantia nigra (SN) and ventral tegmental area (VTA) dopaminergic neurons are, respectively, susceptible or largely unaffected in Parkinson's disease (PD), we searched for protein(s) that regulates this differential sensitivity. Differentially, expressed proteins in SN and VTA were investigated employing two-directional gel electrophoresis- matrix-assisted laser desorption ionization time of flight (MALDI-TOF-TOF) analyses. Prohibitin, which is involved in mitochondrial integrity, was validated using immunoblot, qRT-PCR, and immunohistochemistry in normal mice as well as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-model, PD postmortem human brains, and PD cybrids. In prohibitin over-expression, differentiated SH-SY5Y neurons were investigated for their susceptibility to PD neurotoxin, 1-methyl-4-phenyl-pyridnium (MPP+). Prohibitin, Hsc73, and Cu-Zn superoxide dismutase (Cu-Zn SOD) were highly expressed in VTA, whereas heat shock protein A8 (HSPA8) and 14-3-3ζ/δ were 2-fold more in SN. Prohibitin level was transiently increased in SN but unaltered in VTA on the third day of MPTP-induced mice, whereas in PD human brains, prohibitin was depleted in both these regions. Parallel to mouse SN, an enhanced prohibitin expression was found in human PD cybrids. In MPP+-induced cellular model of PD, reduction in prohibitin level was found to be associated with a loss in its binding with Ndufs3, a mitochondrial complex I protein partner. Prohibitin over-expression resisted MPP+-induced neuronal death by restoring mitochondrial membrane potential, preventing reactive oxygen species generation and cytochrome c release into cytosol. These protective phenomena exerted by prohibitin over-expression altogether hinder caspase 3 activation induced by MPP+. These results imply that prohibitin is an important negotiator protein that regulates dopaminergic cell death in SN and their protection in VTA in PD.

The effects of emodin on cell viability, respiratory burst and gene expression of Nrf2-Keap1 signaling molecules in the peripheral blood leukocytes of blunt snout bream (Megalobrama amblycephala)

We determined the effects of emodin on the cell viability, respiratory burst activity, mRNA levels of antioxidative enzymes (Cu-Zn SOD, CAT and NOX2), and gene expressions of the Nrf2-Keap1 signaling molecules in the peripheral blood leukocytes of blunt snout bream. Triplicate groups of cultured cells were treated with different concentrations of emodin (0.04–25 μg/ml) for 24 h. Results showed that the emodin caused a dramatic loss in cell viability, and occurred in a dose-dependent manner. Emodin exposure (1–25 μg/ml) were significantly induced the ROS generation compared to the control. The respiratory burst and NADPH oxidase activities were significantly induced at a concentration of 0.20 μg/ml, and inhibited at 25 μg/ml. Besides, mRNA levels of antioxidant enzyme genes were dramatically regulated by emodin exposure for 24 h. During low concentrations of exposure, mRNA levels of Cu-Zn SOD in the cells treated with 0.04, 0.20 μg/ml, CAT, NOX2 and Nrf2 in the cells treated with 1 μg/ml were sharply increased, respectively. Whereas, high concentrations were dramatically down-regulated the gene expressions of CAT in the cells treated with 5, 25 μg/ml and NOX2 in the cells treated with 25 μg/ml. Furthermore, sharp increase in Keap1and Bach1 expression levels were observed a dose-dependent manner. In conclusion, this study demonstrated that emodin could induce antioxidant defenses which were involved in cytotoxic activities, respiratory burst and the transcriptional regulation levels of antioxidant enzymes and Nrf2-Keap1 signaling molecules.

Oxidative stress biomarkers, cholinesterase activity and biotransformation enzymes in the liver of dice snake (Natrix tessellata Laurenti) during pre-hibernation and post-hibernation: A possible correlation with heavy metals in the environment

We investigated in the liver of dice snakes during pre- and post-hibernation changes in the following antioxidant parameters: total, manganese and copper zinc containing superoxide dismutases (Tot SOD, MnSOD, CuZn SOD, respectively), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and the concentrations of total glutathione (GSH) and sulfhydryl groups (–SH). In addition, we examined the expression of phase I biotransformation enzyme cytochrome P4501A (CYP1A) and the activity of phase II biotransformation enzyme glutathioneS-transferase (GST), the level of lipid peroxidation (by measuring the thiobarbituric acid-reactive substances (TBARS)), cholinesterase activity (ChE) and metallothionein expression (MT). We also measured the concentrations of heavy metals, including Al, Cd, As, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb and Zn in the water and snake liver during both periods. During the post-hibernation period, the activities of Tot SOD, CuZn SOD and GST and the concentration of GSH were significantly decreased, while GSH-Px and GR activities, the concentrations of –SH groups and TBARS were significantly increased. The activities of Mn SOD, CAT and ChE, and the relative amounts of CYP1A and MT did not significantly change during the investigated periods. The observed differences in the examined parameters probably represent adaptive physiological responses to sudden changes in tissue oxygenation during arousal from hibernation. Our findings also indicate that the accumulated metals modulated the responses of the examined parameters during the investigated periods.

Zymography Methods to Simultaneously Analyze Superoxide Dismutase and Catalase Activities: Novel Application for Yeast Species Identification.

We provide an optimized protocol for a double staining technique to analyze superoxide dismutase enzymatic isoforms Cu-Zn SOD (Sod1) and Mn-SOD (Sod2) and catalase in the same polyacrylamide gel. The use of NaCN, which specifically inhibits yeast Sod1 isoform, allows the analysis of Sod2 isoform while the use of H2O2 allows the analysis of catalase. The identification of a different zymography profiling of SOD and catalase isoforms in different yeast species allowed us to propose this technique as a novel yeast identification and classification strategy.

Effects of inorganic and chelated trace mineral (Cu, Zn, Mn and Fe) premixes in marine rockfish, Sebastes schlegeli (Hilgendorf), fed diets containing phytic acid

The present experiment was conducted to evaluate the effects of trace mineral (Cu, Zn, Mn and Fe) premixes from inorganic and chelated (chelated to 2-hydroxy-4-methylthiobutanoic acid or hydroxy analog of methionine; Mintrex™, Novus International Inc., St. Charles, MO, USA) sources, in rockfish, (Sebastes schlegeli). fed diets containing mineral inhibitor phytic acid. Seven isonitrogenous (46% crude protein/CP) and isocaloric (16.63 KJ available energy per g diet) semi-purified diets comprising of a Basal control and diets supplemented either with the inorganic (I) or chelated premix (M) at three different levels of 0.75 (I0.75/M0.75), 1.5 (I1.5/M1.5) and 3 (I3/M3) g kg−1 diets were formulated. Twenty-four fish averaging individual wet body weight of 9 ± 0.2 g (Mean ± SD) were fed one of the experimental diets in quadratic group for 16 weeks. Average weight gain (WG) of fish fed M3 was significantly higher than that of fish fed Basal control and I1.5 diets (P < 0.05). Whereas, data for the liver and whole body trace mineral contents showed a higher Cu and Zn saturation among fish fed M3 and M1.5 diets (P < 0.05). Furthermore, hepatic Cu-Zn super oxide dismutase (Cu-Zn SOD) activity was recorded to be highest for fish fed M3 diet. Whereas, hepatic thiobarbituric acid-reactive substance (TBARS) value was lowest in fish fed M3 diet (P < 0.05). Challenge test with E. tarda showed an improved disease resistance among the fish fed different levels of trace mineral premixes. Therefore, these results demonstrated a higher efficiency of chelated compared to inorganic source of trace mineral premixes in marine rockfish.

Hydrogen enhances adaptation of rice seedlings to cold stress via the reestablishment of redox homeostasis mediated by miRNA expression

The role of hydrogen gas (H2) in modulating cold tolerance was investigated. A combination of physiological and molecular approaches was used to study the effect of H2 on the alleviation of cold stress. Cold stress stimulated the production of H2 in rice seedlings. The pretreatment with exogenous H2 not only mimicked above physiological response, but also prevented cold-induced growth inhibition. With 0.39 mM H2 pretreatment, rice seedlings exhibited the maximum improving responses, including alleviating the decrease of chlorophyll contents and photosynthetic activity. The lipid peroxidation and the overproduction of reactive oxygen species (ROS) were decreased as well. These results were supported by the changes of total and isozymatic activities of antioxidant enzymes. In comparison with cold stress alone, miR398 transcripts were down-regulated by H2, and expression levels of its targets Cu/Zn-SOD1 (CSD1) and Cu/Zn-SOD2 (CSD2) were increased. By contrast, miR319 transcripts were differentially increased, showing a relatively negative correlation with its target genes PROLIFERATING CELL FACTOR5 (PCF5) and PROLIFERATING CELL FACTOR8 (PCF8). Our results suggested that endogenous H2 might contribute to the enhancement of cold tolerance, at least partially, by the reestablishment of redox homeostasis via miR398 and miR319.

Differential modulation of cellular antioxidant status in zebrafish liver and kidney exposed to low dose arsenic trioxide

Zebrafish were exposed to a nonlethal dose (1/350LC50; 50µg/L) of As2O3 and sampled at 7, 15, 30, 60 and 90 days of treatment. The oxidative stress response was assessed in terms of time-dependent histopathological changes, lipid peroxidation, GSH status, activities of detoxification enzymes and expression of antioxidant genes in liver and kidney. As2O3 treatment enhanced lipid peroxidation except at day 90 in liver and day 30 in kidney. Glutathione depleted significantly in the liver except on day 30; whereas in kidney, it increased initially but thereafter depleted significantly. The liver GST activity was high until day 30, low on day 60 and high on day 90. On the other hand, activity of GST in kidney remained high throughout the exposure. GR activity in liver decreased initially but augmented from 30 days onwards whereas in kidney it remained high until 30 days of exposure. Significant increase in GPx and CAT activities in liver and kidney confirmed oxidative stress in zebrafish which correlated with mRNA expression of antioxidant genes. Upregulation in mRNA level of Cu-Zn Sod in liver and kidney was prominent. Gpx1 upregulation was more conspicuous in kidney as compared to liver while the pattern of Cat expression was almost similar in both the organs. Among the mitochondrial genes, expression of Cox1 was significantly high only after 90 days in liver, while in kidney it enhanced at 7, 30 and 60 days of arsenic exposure. Ucp2 was upregulated in liver after 15 days of exposure but significantly downregulated at day 90; in kidney it remained unchanged at other time points except at day 90. An overall increased expression of Bcl2 further confirmed As2O3 induced oxidative stress in zebrafish liver and kidney. The pattern of mRNA expression of Nrf2 was not uniform and was in accordance to its downstream antioxidant genes. Present findings elucidate that low dose of As2O3 exposure induces a time dependent differential modulation of antioxidant status in liver and kidney of zebrafish in a tissue-specific manner.

Boron influences immune and antioxidant responses by modulating hepatic superoxide dismutase activity under calcium deficit abiotic stress in Wistar rats

The influence of Boron (B) supplementation on immune and antioxidant status of rats with or without abiotic stress induced by dietary calcium (Ca) restriction was studied in a feeding trial of 90 days. Wistar strain rats (3–4 wk age, n=84) were divided into 7 dietary groups (4 replicates of 3 each) viz., normal-calcium (100%) basal diet alone (NC, control) or supplemented with B at 5 (NCB-5), 10 (NCB-10), 20 (NCB-20) and 40ppm (NCB-40) levels; low-calcium (50%) basal diet alone (LC) or supplemented with 40ppm B (LCB-40). After 75 days of experimental feeding, rats were challenged with intraperitoneal injection of sheep RBCs to assess their humoral immunity. At the end of the trial, cell-mediated immunity was assessed as foot pad reaction to sheep RBCs injected into the hind leg paws. Eight rats from each group were sacrificed to collect blood for estimation of minerals and total antioxidant activity, and liver for superoxide dismutase gene expression analysis. Supplementation of graded levels of B (5, 10, 20 and 40ppm) as borax in NC diets significantly increased (P<0.01) the footpad thickness and serum total antioxidant activity, hepatic expression levels of both Cu-Zn SOD (SOD1) and Mn-SOD (SOD2) mRNAs. The erythrocytic SOD activity and humoral response did not differ significantly among the dietary groups. In Ca restricted groups, humoral immune response was significantly decreased (P<0.01) compared to control but increased (P<0.05) with 40ppm B supplementation. Serum levels of copper (Cu) and zinc (Zn) remained similar among the dietary groups, while the manganese (Mn) content was significantly decreased (P<0.01) with increased levels of dietary B. In conclusion, B supplementation increased the hepatic mRNA expression levels of both SOD isoenzymes, thereby improving the immune and antioxidant status.

A cytoplasmic Cu-Zn superoxide dismutase SOD1 contributes to hyphal growth and virulence of Fusarium graminearum

Superoxide dismutases (SODs) are scavengers of superoxide radicals, one of the main reactive oxygen species (ROS) in the cell. SOD-based ROS scavenging system constitutes the frontline defense against intra- and extracellular ROS, but the roles of SODs in the important cereal pathogen Fusarium graminearum are not very clear. There are five SOD genes in F. graminearum genome, encoding cytoplasmic Cu-Zn SOD1 and MnSOD3, mitochondrial MnSOD2 and FeSOD4, and extracellular CuSOD5. Previous studies reported that the expression of SOD1 increased during infection of wheat coleoptiles and florets. In this work we showed that the recombinant SOD1 protein had the superoxide dismutase activity in vitro, and that the SOD1-mRFP fusion protein localized in the cytoplasm of F. graminearum. The Δsod1 mutants had slightly reduced hyphal growth and markedly increased sensitivity to the intracellular ROS generator menadione. The conidial germination under extracellular oxidative stress was significantly delayed in the mutants. Wheat floret infection assay showed that the Δsod1 mutants had a reduced pathogenicity. Furthermore, the Δsod1 mutants had a significant reduction in production of deoxynivalenol mycotoxin. Our results indicate that the cytoplasmic Cu-Zn SOD1 affects fungal growth probably depending on detoxification of intracellular superoxide radicals, and that SOD1-mediated deoxynivalenol production contributes to the virulence of F. graminearum in wheat head infection.

Efficacy of inorganic and chelated trace minerals (Cu, Zn and Mn) premix sources in Pacific white shrimp, Litopenaeus vannamei (Boone) fed plant protein based diets

The present experiment was conducted to evaluate the efficacy of trace minerals (Cu, Zn and Mn) premixes from inorganic and chelated (chelated to 2-hydroxy-4-methylthiobutanoic acid or hydroxy analog of methionine; Mintrex™) sources, in juvenile Pacific white shrimp, (Litopenaeus vannamei) fed plant protein based practical diets. Eight experimental diets comprising a trace minerals (Cu, Zn and Mn) deficient Basal control, and diets supplemented with the trace mineral premixes at four different levels of 2.5 (M2.5), 5 (M5), 7.5 (M7.5) and 8.5g/kg (M8.5) from chelated source and at three different levels of 5 (I5), 8.5 (I8.5) and 20g/kg (I20) from inorganic source were formulated. Eleven numbers of juvenile shrimp averaging 0.6±0.01g (mean±SD) were fed one of the eight experimental diets in triplicate groups for 8weeks. At the end of the feeding trial, shrimp fed M2.5 and I8.5 diets exhibited the similar final weight (FW) and weight gain (WG) (P<0.05). Performance for Cu and Zn content in the hepatopancreas tissues and whole body showed equal efficiency of M5 compared to I8.5 diet (P<0.05). Whereas, nonspecific enzyme, CuZn super oxide dismutase (CuZn SOD) from the serum and hepatopancreas tissue was recorded to be peaked for the group of shrimp fed M5 diet. Moreover, plasma protein and glucose levels were recorded to be similar between the groups of shrimp fed M2.5 and I20 diets (P<0.05). Therefore, the present experiment demonstrated, a higher efficiency of chelated over inorganic source of trace mineral premix in Pacific white shrimp, (L. vannamei) fed plant protein based diets. Statement of relevanceThe significance of trace mineral bioavailability has become more important as the composition of majority of commercial fish feed has been changing and there is an increased use of dietary plant protein. As a result, the bioavailability of trace minerals is being adversely affected by the presence of antagonistic factor such as phytic acid in plant protein. Even though, our knowledge in fish nutrition has advanced significantly, the information on trace minerals requirement is still limited and fragmentary. Inorganic form (sulfate/nitrate) of trace mineral has traditionally been used in aquafeed formulation. However, the limited bioavailability of inorganic source of trace mineral due to its higher affinity to antinutrients has hastened the search for alternative form of inorganic trace minerals. Overall performance observed in the present experiments vouched the potential benefit of using chelated trace mineral, Cu, Zn & Mn premix in marine shrimp, Pacific white shrimp to promote the optimum growth, trace minerals saturation in shrimp body and tissue as well as to ensure the optimum enzyme activity and health of cultured shrimp. The present experiment opens a new avenue to compare the efficacy of inorganic and chelated source of trace minerals in other commercially important marine and fresh water fish species.Whereas, the sustainability issue has put a new dimension in aquafeed formulation with a wide array of new ingredients and additives, on the other hand, the importance of basic nutrient such as trace minerals is still in sideline. Substantial investment and integrated scientific efforts are warranted to bridge the knowledge gap and further improve our understandings on the significance of dietary trace mineral in fish nutrition and health at the least cost to environment.

Coordinated Changes in Antioxidative Enzymes Protect the Photosynthetic Machinery from Salinity Induced Oxidative Damage and Confer Salt Tolerance in an Extreme Halophyte Salvadora persica L.

Salinity-induced modulations in growth, photosynthetic pigments, relative water content (RWC), lipid peroxidation, photosynthesis, photosystem II efficiency, and changes in activity of various antioxidative enzymes were studied in the halophyte Salvadora persica treated with various levels of salinity (0, 250, 500, 750, and 1000 mM NaCl) to obtain an insight into the salt tolerance ability of this halophyte. Both fresh and dry biomass as well as leaf area (LA) declined at all levels of salinity whereas salinity caused an increase in leaf succulence. A gradual increase was observed in the Na+ content of leaf with increasing salt concentration up to 750 mM NaCl, but at higher salt concentration (1000 mM NaCl), the Na+ content surprisingly dropped down to the level of 250 mM NaCl. The chlorophyll and carotenoid contents of the leaf remained unaffected by salinity. The photosynthetic rate (PN), stomatal conductance (gs), the transpiration rate (E), quantum yield of PSII (ΦPSII), photochemical quenching (qP), and electron transport rate remained unchanged at low salinity (250 to 500 mM NaCl) whereas, significant reduction in these parameters were observed at high salinity (750 to 1000 mM NaCl). The RWC% and water use efficiency (WUE) of leaf remained unaffected by salinity. The salinity had no effect on maximum quantum efficiency of PS II (Fv/Fm) which indicates that PS II is not perturbed by salinity-induced oxidative damage. Analysis of the isoforms of antioxidative enzymes revealed that the leaves of S. persica have two isoforms each of Mn-SOD and Fe-SOD and one isoform of Cu-Zn SOD, three isoforms of POX, two isoforms of APX and one isoform of CAT. There was differential responses in activity and expression of different isoforms of various antioxidative enzymes. The malondialdehyde (MDA) content (a product of lipid peroxidation) of leaf remained unchanged in S. persica treated with various levels of salinity. Our results suggest that the absence of pigment degradation, the reduction of water loss, and the maintenance of WUE and protection of PSII from salinity-induced oxidative damage by the coordinated changes in antioxidative enzymes are important factors responsible for salt tolerance of S. persica.

Evidence for the Cost of Reproduction in Humans: High Lifetime Reproductive Effort Is Associated with Greater Oxidative Stress in Post-Menopausal Women.

Life history theory predicts trade-offs between reproductive effort and maternal survivorship in energy-restricted environments. However, empirical evidence for the positive association between maternal mortality and reproductive effort from energetically challenged human populations are mixed and physiological mechanisms that may underlie this association are poorly understood. We hypothesized that increases in aerobic metabolism during repeated periods of pregnancy and lactation result in increased oxidative stress that may contribute to somatic deterioration, vulnerability to illness, and accelerated aging. We therefore predicted that lifetime gravidity and parity would be related to levels of biomarkers of oxidative stress, as well as antioxidative defence enzymes in post-menopausal women. Our hypothesis was supported by positive linear associations between levels of 8-OHdG, a biomarker of DNA oxidative damage (β = 0.21, p<0.05), levels of antioxidative defence enzyme Cu-Zn SOD (β = 0.25, p<0.05), and number of lifetime pregnancies. Furthermore, independent of age and health status, post-menopausal women with higher gravidity and parity (> = 4 pregnancies per lifetime) had 20% higher levels of 8-OHdG and 60% higher levels of Cu-Zn SOD compared to women with lower gravidity and parity (<4 pregnancies per lifetime). Our results present the first evidence for oxidative stress as a possible cost of reproductive effort in humans.