Redox susceptibility of SOD1 mutants is associated with the differential response to CCS over-expression in vivo.

PubMed

Son, Marjatta; Fu, Qiao; Puttaparthi, Krishna; Matthews, Christina M; Elliott, Jeffrey L

2009-04-01

Over-expression of CCS in G93A SOD1 mice accelerates neurological disease and enhances mitochondrial pathology. We studied the effect of CCS over-expression in transgenic mice expressing G37R, G86R or L126Z SOD1 mutations in order to understand factors which influence mitochondrial dysfunction. Over-expression of CCS markedly decreased survival and produced mitochondrial vacuolation in G37R SOD1 mice but not in G86R or L126Z SOD1 mice. Moreover, CCS/G37R SOD1 spinal cord showed specific reductions in mitochondrial complex IV subunits consistent with an isolated COX deficiency, while no such reductions were detected in CCS/G86R or CCS/L126Z SOD1 mice. CCS over-expression increased the ratio of reduced to oxidized SOD1 monomers in the spinal cords of G37R SOD1 as well as G93A SOD1 mice, but did not influence the redox state of G86R or L126Z SOD1 monomers. The effects of CCS on disease are SOD1 mutation dependent and correlate with SOD1 redox susceptibility.

Superoxide Dismutases, SOD1 and SOD2, Play a Distinct Role in the Fat Body during Pupation in Silkworm Bombyx mori

PubMed Central

Nojima, Yosui; Ito, Katsuhiko; Ono, Hiromasa; Nakazato, Takeru; Bono, Hidemasa; Yokoyama, Takeshi; Sato, Ryoichi; Suetsugu, Yoshitaka; Nakamura, Yuki; Yamamoto, Kimiko; Satoh, Jun-ichi; Tabunoki, Hiroko; Fugo, Hajime

2015-01-01

One way that aerobic biological systems counteract the generation of reactive oxygen species (ROS) is with superoxide dismutase proteins SOD1 and SOD2 that metabolize superoxide radicals to molecular oxygen and hydrogen peroxide or scavenge oxygen radicals produced by the extensive oxidation-reduction and electron-transport reactions that occur in mitochondria. We characterized SOD1 and SOD2 of Bombyx mori isolated from the fat body of larvae. Immunological analysis demonstrated the presence of BmSOD1 and BmSOD2 in the silk gland, midgut, fat body, Malpighian tubules, testis and ovary from larvae to adults. We found that BmSOD2 had a unique expression pattern in the fat body through the fifth instar larval developmental stage. The anti-oxidative functions of BmSOD1 and BmSOD2 were assessed by exposing larvae to insecticide rotenone or vasodilator isosorbide dinitrate, which is an ROS generator in BmN4 cells; however, exposure to these compounds had no effect on the expression levels of either BmSOD protein. Next, we investigated the physiological role of BmSOD1 and BmSOD2 under environmental oxidative stress, applied through whole-body UV irradiation and assayed using quantitative RT-PCR, immunoblotting and microarray analysis. The mRNA expression level of both BmSOD1 and BmSOD2 was markedly increased but protein expression level was increased only slightly. To examine the differences in mRNA and protein level due to UV irradiation intensity, we performed microarray analysis. Gene set enrichment analysis revealed that genes in the insulin signaling pathway and PPAR signaling pathway were significantly up-regulated after 6 and 12 hours of UV irradiation. Taken together, the activities of BmSOD1 and BmSOD2 may be related to the response to UV irradiation stress in B. mori. These results suggest that BmSOD1 and BmSOD2 modulate environmental oxidative stress in the cell and have a specific role in fat body of B. mori during pupation. PMID:25714339

Complete Amino Acid Sequence of a Copper/Zinc-Superoxide Dismutase from Ginger Rhizome.

PubMed

Nishiyama, Yuki; Fukamizo, Tamo; Yoneda, Kazunari; Araki, Tomohiro

2017-04-01

Superoxide dismutase (SOD) is an antioxidant enzyme protecting cells from oxidative stress. Ginger (Zingiber officinale) is known for its antioxidant properties, however, there are no data on SODs from ginger rhizomes. In this study, we purified SOD from the rhizome of Z. officinale (Zo-SOD) and determined its complete amino acid sequence using N terminal sequencing, amino acid analysis, and de novo sequencing by tandem mass spectrometry. Zo-SOD consists of 151 amino acids with two signature Cu/Zn-SOD motifs and has high similarity to other plant Cu/Zn-SODs. Multiple sequence alignment showed that Cu/Zn-binding residues and cysteines forming a disulfide bond, which are highly conserved in Cu/Zn-SODs, are also present in Zo-SOD. Phylogenetic analysis revealed that plant Cu/Zn-SODs clustered into distinct chloroplastic, cytoplasmic, and intermediate groups. Among them, only chloroplastic enzymes carried amino acid substitutions in the region functionally important for enzymatic activity, suggesting that chloroplastic SODs may have a function distinct from those of SODs localized in other subcellular compartments. The nucleotide sequence of the Zo-SOD coding region was obtained by reverse-translation, and the gene was synthesized, cloned, and expressed. The recombinant Zo-SOD demonstrated pH stability in the range of 5-10, which is similar to other reported Cu/Zn-SODs, and thermal stability in the range of 10-60 °C, which is higher than that for most plant Cu/Zn-SODs but lower compared to the enzyme from a Z. officinale relative Curcuma aromatica.

Peroxisomal copper, zinc superoxide dismutase. Characterization of the isoenzyme from watermelon cotyledons.

PubMed Central

Bueno, P; Varela, J; Gimeénez-Gallego, G; del Río, L A

1995-01-01

The biochemical and immunochemical characterization of a superoxide dismutase (SOD, EC 1.15.1.1) from peroxisomal origin has been carried out. The enzyme is a Cu,Zn-containing SOD (CuZn-SOD) located in the matrix of peroxisomes from watermelon (Citrullus vulgaris Schrad.) cotyledons (L.M. Sandalio and L.A. del Río [1988] Plant Physiol 88: 1215-1218). The amino acid composition of the enzyme was determined. Analysis by reversed-phase high-performance liquid chromatography of the peroxisomal CuZn-SOD incubated with 6 M guanidine-HCl indicated that this enzyme contained a noncovalently bound chromophore group that was responsible for the absorbance peak of the native enzyme at 260 nm. The amino acid sequence of the peroxisomal CuZn-SOD was determined by Edman degradation. Comparison of its sequence with those reported for other plant SODs revealed homologies of about 70% with cytosolic CuZn-SODs and of 90% with chloroplastic CuZn-SODs. The peroxisomal SOD has a high thermal stability and resistance to inactivation by hydrogen peroxide. A polyclonal antibody was raised against peroxisomal CuZn-SOD, and by western blotting the antibody cross-reacted with plant CuZn-SODs but did not recognize either plant Mn-SOD or bacterial Fe-SOD. The antiSOD-immunoglobulin G showed a weak cross-reaction with bovine erythrocytes and liver CuZn-SODs, and also with cell-free extracts from trout liver. The possible function of this CuZn-SOD in the oxidative metabolism of peroxisomes is discussed. PMID:7630940

Parasitization by Scleroderma guani influences expression of superoxide dismutase genes in Tenebrio molitor

USDA-ARS?s Scientific Manuscript database

Superoxide dismutase (SOD) is an antioxidant enzyme involved in detoxifying reactive oxygen species. In this study, we identified genes encoding the extracellular and intracellular copper-zinc SODs (ecCuZnSOD and icCuZnSOD) and a manganese SOD (MnSOD) in the yellow mealworm beetle, Tenebrio molitor....

Acylation of Superoxide Dismutase 1 (SOD1) at K122 Governs SOD1-Mediated Inhibition of Mitochondrial Respiration

PubMed Central

Banks, Courtney J.; Rodriguez, Nathan W.; Gashler, Kyle R.; Pandya, Rushika R.; Mortenson, Jeffrey B.; Whited, Matthew D.; Soderblom, Erik J.; Thompson, J. Will; Moseley, M. Arthur; Reddi, Amit R.; Tessem, Jeffery S.; Torres, Matthew P.; Bikman, Benjamin T.

2017-01-01

ABSTRACT In this study, we employed proteomics to identify mechanisms of posttranslational regulation on cell survival signaling proteins. We focused on Cu-Zn superoxide dismutase (SOD1), which protects cells from oxidative stress. We found that acylation of K122 on SOD1, while not impacting SOD1 catalytic activity, suppressed the ability of SOD1 to inhibit mitochondrial metabolism at respiratory complex I. We found that deacylase depletion increased K122 acylation on SOD1, which blocked the suppression of respiration in a K122-dependent manner. In addition, we found that acyl-mimicking mutations at K122 decreased SOD1 accumulation in mitochondria, initially hinting that SOD1 may inhibit respiration directly within the intermembrane space (IMS). However, surprisingly, we found that forcing the K122 acyl mutants into the mitochondria with an IMS-targeting tag did not recover their ability to suppress respiration. Moreover, we found that suppressing or boosting respiration levels toggled SOD1 in or out of the mitochondria, respectively. These findings place SOD1-mediated inhibition of respiration upstream of its mitochondrial localization. Lastly, deletion-rescue experiments show that a respiration-defective mutant of SOD1 is also impaired in its ability to rescue cells from toxicity caused by SOD1 deletion. Together, these data suggest a previously unknown interplay between SOD1 acylation, metabolic regulation, and SOD1-mediated cell survival. PMID:28739857

Oxidation of the Tryptophan 32 Residue of Human Superoxide Dismutase 1 Caused by Its Bicarbonate-dependent Peroxidase Activity Triggers the Non-amyloid Aggregation of the Enzyme*

PubMed Central

Coelho, Fernando R.; Iqbal, Asif; Linares, Edlaine; Silva, Daniel F.; Lima, Filipe S.; Cuccovia, Iolanda M.; Augusto, Ohara

2014-01-01

The role of oxidative post-translational modifications of human superoxide dismutase 1 (hSOD1) in the amyotrophic lateral sclerosis (ALS) pathology is an attractive hypothesis to explore based on several lines of evidence. Among them, the remarkable stability of hSOD1WT and several of its ALS-associated mutants suggests that hSOD1 oxidation may precede its conversion to the unfolded and aggregated forms found in ALS patients. The bicarbonate-dependent peroxidase activity of hSOD1 causes oxidation of its own solvent-exposed Trp32 residue. The resulting products are apparently different from those produced in the absence of bicarbonate and are most likely specific for simian SOD1s, which contain the Trp32 residue. The aims of this work were to examine whether the bicarbonate-dependent peroxidase activity of hSOD1 (hSOD1WT and hSOD1G93A mutant) triggers aggregation of the enzyme and to comprehend the role of the Trp32 residue in the process. The results showed that Trp32 residues of both enzymes are oxidized to a similar extent to hSOD1-derived tryptophanyl radicals. These radicals decayed to hSOD1-N-formylkynurenine and hSOD1-kynurenine or to a hSOD1 covalent dimer cross-linked by a ditryptophan bond, causing hSOD1 unfolding, oligomerization, and non-amyloid aggregation. The latter process was inhibited by tempol, which recombines with the hSOD1-derived tryptophanyl radical, and did not occur in the absence of bicarbonate or with enzymes that lack the Trp32 residue (bovine SOD1 and hSOD1W32F mutant). The results support a role for the oxidation products of the hSOD1-Trp32 residue, particularly the covalent dimer, in triggering the non-amyloid aggregation of hSOD1. PMID:25237191

Replacement of a cytosolic copper/zinc superoxide dismutase by a novel cytosolic manganese superoxide dismutase in crustaceans that use copper (haemocyanin) for oxygen transport.

PubMed Central

Brouwer, Marius; Hoexum Brouwer, Thea; Grater, Walter; Brown-Peterson, Nancy

2003-01-01

The blue crab, Callinectes sapidus, which uses the copper-dependent protein haemocyanin for oxygen transport, lacks the ubiquitous cytosolic copper-dependent enzyme copper/zinc superoxide dismutase (Cu,ZnSOD) as evidenced by undetectable levels of Cu,ZnSOD activity, protein and mRNA in the hepatopancreas (the site of haemocyanin synthesis) and gills. Instead, the crab has an unusual cytosolic manganese SOD (cytMnSOD), which is retained in the cytosol, because it lacks a mitochondrial transit peptide. A second familiar MnSOD is present in the mitochondria (mtMnSOD). This unique phenomenon occurs in all Crustacea that use haemocyanin for oxygen transport. Molecular phylogeny analysis suggests the MnSOD gene duplication is as old as the origin of the arthropod phylum. cytMnSOD activity in the hepatopancreas changes during the moulting cycle of the crab. Activity is high in intermoult crabs and non-detectable in postmoult papershell crabs. mtMnSOD is present in all stages of the moulting cycle. Despite the lack of cytCu,ZnSOD, crabs have an extracellular Cu,ZnSOD (ecCu,ZnSOD) that is produced by haemocytes, and is part of a large, approx. 160 kDa, covalently-linked protein complex. ecCu,ZnSOD is absent from the hepatopancreas of intermoult crabs, but appears in this tissue at premoult. However, no ecCu,ZnSOD mRNA can be detected, suggesting that the protein is recruited from the haemolymph. Screening of different taxa of the arthropod phylum for Cu,ZnSOD activity shows that those crustaceans that use haemoglobin for oxygen transport have retained cytCu,ZnSOD. It appears, therefore, that the replacement of cytCu,ZnSOD with cytMnSOD is part of an adaptive response to the dynamic, haemocyanin-linked, fluctuations in copper metabolism that occur during the moulting cycle of the crab. PMID:12769817

Unique molecular properties of superoxide dismutase from teleost fish skin.

PubMed

Nakano, T; Sato, M; Takeuchi, M

1995-02-27

A unique Cu,Zn-SOD was found and isolated from plaice Paralichthys olivaceus skin. Surprisingly, the properties of purified fish skin SOD were very different from those of SOD from other sources reported so far. The purified SOD was composed of four same subunits of 16 kDa and the molecular weight of the native SOD was found to be around 65 kDa. The dominant amino acids of the SOD were Ser, Thr, Pro and Glu. Above 70 degrees C, thermostability of the SOD was much lower than that of bovine erythrocyte Cu,Zn-SOD.

Isolated cytochrome c oxidase deficiency in G93A SOD1 mice overexpressing CCS protein.

PubMed

Son, Marjatta; Leary, Scot C; Romain, Nadine; Pierrel, Fabien; Winge, Dennis R; Haller, Ronald G; Elliott, Jeffrey L

2008-05-02

G93A SOD1 transgenic mice overexpressing CCS protein develop an accelerated disease course that is associated with enhanced mitochondrial pathology and increased mitochondrial localization of mutant SOD1. Because these results suggest an effect of mutant SOD1 on mitochondrial function, we assessed the enzymatic activities of mitochondrial respiratory chain complexes in the spinal cords of CCS/G93A SOD1 and control mice. CCS/G93A SOD1 mouse spinal cord demonstrates a 55% loss of complex IV (cytochrome c oxidase) activity compared with spinal cord from age-matched non-transgenic or G93A SOD1 mice. In contrast, CCS/G93A SOD1 spinal cord shows no reduction in the activities of complex I, II, or III. Blue native gel analysis further demonstrates a marked reduction in the levels of complex IV but not of complex I, II, III, or V in spinal cords of CCS/G93A SOD1 mice compared with non-transgenic, G93A SOD1, or CCS/WT SOD1 controls. With SDS-PAGE analysis, spinal cords from CCS/G93A SOD1 mice showed significant decreases in the levels of two structural subunits of cytochrome c oxidase, COX1 and COX5b, relative to controls. In contrast, CCS/G93A SOD1 mouse spinal cord showed no reduction in levels of selected subunits from complexes I, II, III, or V. Heme A analyses of spinal cord further support the existence of cytochrome c oxidase deficiency in CCS/G93A SOD1 mice. Collectively, these results establish that CCS/G93A SOD1 mice manifest an isolated complex IV deficiency which may underlie a substantial part of mutant SOD1-induced mitochondrial cytopathy.

Histone deacetylation contributes to low extracellular superoxide dismutase expression in human idiopathic pulmonary arterial hypertension

PubMed Central

Woods, Crystal; Stearman, Robert S.; Venkataraman, Sujatha; Ferguson, Bradley S.; Swain, Kalin; Bowler, Russell P.; Geraci, Mark W.; Ihida-Stansbury, Kaori; Stenmark, Kurt R.; McKinsey, Timothy A.; Domann, Frederick E.

2016-01-01

Epigenetic mechanisms, including DNA methylation and histone acetylation, regulate gene expression in idiopathic pulmonary arterial hypertension (IPAH). These mechanisms can modulate expression of extracellular superoxide dismutase (SOD3 or EC-SOD), a key vascular antioxidant enzyme, and loss of vascular SOD3 worsens outcomes in animal models of pulmonary arterial hypertension. We hypothesized that SOD3 gene expression is decreased in patients with IPAH due to aberrant DNA methylation and/or histone deacetylation. We used lung tissue and pulmonary artery smooth muscle cells (PASMC) from subjects with IPAH at transplantation and from failed donors (FD). Lung SOD3 mRNA expression and activity was decreased in IPAH vs. FD. In contrast, mitochondrial SOD (Mn-SOD or SOD2) protein expression was unchanged and intracellular SOD activity was unchanged. Using bisulfite sequencing in genomic lung or PASMC DNA, we found the methylation status of the SOD3 promoter was similar between FD and IPAH. Furthermore, treatment with 5-aza-2′-deoxycytidine did not increase PASMC SOD3 mRNA, suggesting DNA methylation was not responsible for PASMC SOD3 expression. Though total histone deacetylase (HDAC) activity, histone acetyltransferase (HAT) activity, acetylated histones, and acetylated SP1 were similar between IPAH and FD, treatment with two selective class I HDAC inhibitors increased SOD3 only in IPAH PASMC. Class I HDAC3 siRNA also increased SOD3 expression. Trichostatin A, a pan-HDAC inhibitor, decreased proliferation in IPAH, but not in FD PASMC. These data indicate that histone deacetylation, specifically via class I HDAC3, decreases SOD3 expression in PASMC and HDAC inhibitors may protect IPAH in part by increasing PASMC SOD3 expression. PMID:27233998

Cross-Reactivity of Schistosoma mansoni Cytosolic Superoxide Dismutase, a Protective Vaccine Candidate, with Host Superoxide Dismutase and Identification of Parasite-Specific B Epitopes

PubMed Central

Carvalho-Queiroz, Claudia; Cook, Rosemary; Wang, Ching C.; Correa-Oliveira, Rodrigo; Bailey, Nicola A.; Egilmez, Nejat K.; Mathiowitz, Edith; LoVerde, Philip T.

2004-01-01

Schistosoma mansoni, an intravascular parasite, has evolved a number of immune evasion mechanisms to establish itself in the host, such as antioxidant enzymes. Our laboratory has demonstrated that the highest levels of certain antioxidant enzymes are found in adult worms, which are the least susceptible to immune killing. Vaccination of mice with naked DNA constructs containing the gene encoding Cu/Zn cytosolic superoxide dismutase (SmCT-SOD) showed significant levels of protection compared to a control group, and our data demonstrate that the adult worms are a target of the immune response that confers resistance in SmCT-SOD DNA-vaccinated mice. Because SmCT-SOD shows significant identity with the human homologue, we evaluated the reactivity of anti-SmCT-SOD antibodies derived from SmCT-SOD-immunized mice and rabbits and from S. mansoni-infected individuals to human superoxide dismutase (hSOD) and SmCT-SOD parasite-specific peptides to assess the potential for autoimmune responses from immunization with the recombinant molecule. In addition, we evaluated the ability of various SmCT-SOD adjuvant-delivered immunizations to induce cross-reactive antibodies. Both mouse and rabbit antibodies generated against SmCT-SOD recognized the denatured form of hSOD. The same antibodies did not recognize nondenatured hSOD. Sera from infected individuals with different clinical forms of schistosomiasis recognized SmCT-SOD but not hSOD. Antibodies from mice immunized with different SmCT-SOD-containing formulations of both DNA and protein were able to recognize SmCT-SOD-derived peptides but not soluble hSOD. All together, these findings serve as a basis for developing a subunit vaccine against schistosomiasis. PMID:15102772

Parasitization by Scleroderma guani influences expression of superoxide dismutase genes in Tenebrio molitor.

PubMed

Zhu, Jia-Ying; Ze, Sang-Zi; Stanley, David W; Yang, Bin

2014-09-01

Superoxide dismutase (SOD) is an antioxidant enzyme involved in detoxifying reactive oxygen species. In this study, we identified genes encoding the extracellular and intracellular copper-zinc SODs (ecCuZnSOD and icCuZnSOD) and a manganese SOD (MnSOD) in the yellow mealworm beetle, Tenebrio molitor. The cDNAs for ecCuZnSOD, icCuZnSOD, and MnSOD, respectively, encode 24.55, 15.81, and 23.14 kDa polypeptides, which possess structural features typical of other insect SODs. They showed 20-94% identity to other known SOD sequences from Bombyx mori, Musca domestica, Nasonia vitripennis, Pediculus humanus corporis, and Tribolium castaneum. Expression of these genes was analyzed in selected tissues and developmental stages, and following exposure to Escherichia coli and parasitization by Scleroderma guani. We recorded expression of all three SODs in cuticle, fat body, and hemocytes and in the major developmental stages. Relatively higher expressions were detected in late-instar larvae and pupae, compared to other developmental stages. Transcriptional levels were upregulated following bacterial infection. Analysis of pupae parasitized by S. guani revealed that expression of T. molitor SOD genes was significantly induced following parasitization. We infer that these genes act in immune response and in host-parasitoid interactions. © 2014 Wiley Periodicals, Inc.

Relationship of the superoxide dismutase genes, sodA and sodB, to the iron uptake (/ital fur/) regulon in /ital Escherichia coli/ K-12

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niederhoffer, E.C.; Naranjo, C.M.; Fee, J.A.

1988-01-01

Expression of sodA, as indicated by MnSod activity is normal in /ital fur/ mutants. This suggests that sodA is not a member of the /ital fur/ regulon and that the putative Fe-binding, regulatory protein of sodA, suggested by Moody and Hassan is not the Fur protein. by contrast, expression of sodB, as indicated by FeSod activity, is completely blocked in /ital fur/ mutants and the effect is restored by transformation with a plasmid having a normal /ital fur/ locus. The observations suggest that Fur, either directly or indirectly, controls SodB biosynthesis. Additional observations are described which indicate that SodB andmore » Fur act together in a complicated fashion to control the biosynthesis of enterobactin. 26 refs., 3 tabs.« less

Oxidized/misfolded superoxide dismutase-1: the cause of all amyotrophic lateral sclerosis?

PubMed

Kabashi, Edor; Valdmanis, Paul N; Dion, Patrick; Rouleau, Guy A

2007-12-01

The identification in 1993 of superoxide dismutase-1 (SOD1) mutations as the cause of 10 to 20% of familial amyotrophic lateral sclerosis cases, which represents 1 to 2% of all amyotrophic lateral sclerosis (ALS) cases, prompted a substantial amount of research into the mechanisms of SOD1-mediated toxicity. Recent experiments have demonstrated that oxidation of wild-type SOD1 leads to its misfolding, causing it to gain many of the same toxic properties as mutant SOD1. In vitro studies of oxidized/misfolded SOD1 and in vivo studies of misfolded SOD1 have indicated that these protein species are selectively toxic to motor neurons, suggesting that oxidized/misfolded SOD1 could lead to ALS even in individuals who do not carry an SOD1 mutation. It has also been reported that glial cells secrete oxidized/misfolded mutant SOD1 to the extracellular environment, where it can trigger the selective death of motor neurons, offering a possible explanation for the noncell autonomous nature of mutant SOD1 toxicity and the rapid progression of disease once the first symptoms develop. Therefore, considering that sporadic (SALS) and familial ALS (FALS) cases are clinically indistinguishable, the toxic properties of mutated SOD1 are similar to that of oxidized/misfolded wild-type SOD1 (wtSOD1), and secreted/extracellular misfolded SOD1 is selectively toxic to motor neurons, we propose that oxidized/misfolded SOD1 is the cause of most forms of classic ALS and should be a prime target for the design of ALS treatments.

A Comparison of Two Yeast MnSODs: Mitochondrial Saccharomyces cerevisiae versus Cytosolic Candida albicans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheng Y.; Cabelli D.; Stich, T.A.

Human MnSOD is significantly more product-inhibited than bacterial MnSODs at high concentrations of superoxide (O{sub 2}{sup -}). This behavior limits the amount of H{sub 2}O{sub 2} produced at high [O{sub 2}{sup -}]; its desirability can be explained by the multiple roles of H{sub 2}O{sub 2} in mammalian cells, particularly its role in signaling. To investigate the mechanism of product inhibition in MnSOD, two yeast MnSODs, one from Saccharomyces cerevisiae mitochondria (ScMnSOD) and the other from Candida albicans cytosol (CaMnSODc), were isolated and characterized. ScMnSOD and CaMnSODc are similar in catalytic kinetics, spectroscopy, and redox chemistry, and they both rest predominantlymore » in the reduced state (unlike most other MnSODs). At high [O{sub 2}{sup -}], the dismutation efficiencies of the yeast MnSODs surpass those of human and bacterial MnSODs, due to very low level of product inhibition. Optical and parallel-mode electron paramagnetic resonance (EPR) spectra suggest the presence of two Mn{sup 3+} species in yeast Mn{sup 3+}SODs, including the well-characterized 5-coordinate Mn{sup 3+} species and a 6-coordinate L-Mn{sup 3+} species with hydroxide as the putative sixth ligand (L). The first and second coordination spheres of ScMnSOD are more similar to bacterial than to human MnSOD. Gln154, an H-bond donor to the Mn-coordinated solvent molecule, is slightly further away from Mn in yeast MnSODs, which may result in their unusual resting state. Mechanistically, the high efficiency of yeast MnSODs could be ascribed to putative translocation of an outer-sphere solvent molecule, which could destabilize the inhibited complex and enhance proton transfer from protein to peroxide. Our studies on yeast MnSODs indicate the unique nature of human MnSOD in that it predominantly undergoes the inhibited pathway at high [O{sub 2}{sup -}].« less

A Comparison of Two Yeast MnSODs: Mitochondrial Saccharomyces cerevisiae versus Cytosolic Candida albicans

PubMed Central

Sheng, Yuewei; Stich, Troy A.; Barnese, Kevin; Gralla, Edith B.; Cascio, Duilio; Britt, R. David; Cabelli, Diane E.; Valentine, Joan Selverstone

2011-01-01

Human MnSOD is significantly more product-inhibited than bacterial MnSODs at high concentrations of superoxide (O2−). This behavior limits the amount of H2O2 produced at high [O2−]; its desirability can be explained by the multiple roles of H2O2 in mammalian cells, particularly its role in signaling. To investigate the mechanism of product inhibition in MnSOD, two yeast MnSODs, one from Saccharomyces cerevisiae mitochondria (ScMnSOD) and the other from Candida albicans cytosol (CaMnSODc), were isolated and characterized. ScMnSOD and CaMnSODc are similar in catalytic kinetics, spectroscopy and redox chemistry, and they both rest predominantly in the reduced state (unlike most other MnSODs). At high [O2−] the dismutation efficiencies of the yeast MnSODs surpass those of human and bacterial MnSODs, due to very low level of product inhibition. Optical and parallel-mode electron paramagnetic resonance (EPR) spectra suggest the presence of two Mn3+ species in yeast Mn3+SODs, including the well-characterized 5-coordinate Mn3+ species and a 6-coordinate L-Mn3+ species with hydroxide as the putative sixth ligand (L). The first and second coordination spheres of ScMnSOD are more similar to bacterial than to human MnSOD. Gln154, an H-bond donor to the Mn-coordinated solvent molecule, is slightly further away from Mn in yeast MnSODs, which may result in their unusual resting state. Mechanistically, the high efficiency of yeast MnSODs could be ascribed to putative translocation of an outer-sphere solvent molecule, which could destabilize the inhibited complex and enhance proton transfer from protein to peroxide. Our studies on yeast MnSODs indicate the unique nature of human MnSOD in that it predominantly undergoes the inhibited pathway at high [O2−]. PMID:22077216

Cloning and expression of an iron-containing superoxide dismutase in the parasitic protist, Trichomonas vaginalis.

PubMed

Viscogliosi, E; Delgado-Viscogliosi, P; Gerbod, D; Dauchez, M; Gratepanche, S; Alix, A J; Dive, D

1998-04-01

A superoxide dismutase (SOD) gene of the parasitic protist Trichomonas vaginalis was cloned, sequenced, expressed in Escherichia coli, and its gene product characterized. It is an iron-containing dimeric protein with a monomeric mass of 22,067 Da. Southern blots analyses suggested the presence of seven iron-containing (FeSOD) gene copies. Hydrophobic cluster analysis revealed some peculiarities in the 2D structure of the FeSOD from T. vaginalis and a strong structural conservation between prokaryotic and eukaryotic FeSODs. Phylogenetic reconstruction of the SOD sequences confirmed the dichotomy between FeSODs and manganese-containing SODs. FeSODs of protists appeared to group together with homologous proteobacterial enzymes suggesting a possible origin of eukaryotic FeSODs through an endosymbiotic event.

S-acylation of SOD1, CCS, and a stable SOD1-CCS heterodimer in human spinal cords from ALS and non-ALS subjects.

PubMed

Antinone, Sarah E; Ghadge, Ghanashyam D; Ostrow, Lyle W; Roos, Raymond P; Green, William N

2017-01-25

Previously, we found that human Cu, Zn-superoxide dismutase (SOD1) is S-acylated (palmitoylated) in vitro and in amyotrophic lateral sclerosis (ALS) mouse models, and that S-acylation increased for ALS-causing SOD1 mutants relative to wild type. Here, we use the acyl resin-assisted capture (acyl-RAC) assay to demonstrate S-acylation of SOD1 in human post-mortem spinal cord homogenates from ALS and non-ALS subjects. Acyl-RAC further revealed that endogenous copper chaperone for SOD1 (CCS) is S-acylated in both human and mouse spinal cords, and in vitro in HEK293 cells. SOD1 and CCS formed a highly stable heterodimer in human spinal cord homogenates that was resistant to dissociation by boiling, denaturants, or reducing agents and was not observed in vitro unless both SOD1 and CCS were overexpressed. Cysteine mutations that attenuate SOD1 maturation prevented the SOD1-CCS heterodimer formation. The degree of S-acylation was highest for SOD1-CCS heterodimers, intermediate for CCS monomers, and lowest for SOD1 monomers. Given that S-acylation facilitates anchoring of soluble proteins to cell membranes, our findings suggest that S-acylation and membrane localization may play an important role in CCS-mediated SOD1 maturation. Furthermore, the highly stable S-acylated SOD1-CCS heterodimer may serve as a long-lived maturation intermediate in human spinal cord.

S-acylation of SOD1, CCS, and a stable SOD1-CCS heterodimer in human spinal cords from ALS and non-ALS subjects

PubMed Central

Antinone, Sarah E.; Ghadge, Ghanashyam D.; Ostrow, Lyle W.; Roos, Raymond P.; Green, William N.

2017-01-01

Previously, we found that human Cu, Zn-superoxide dismutase (SOD1) is S-acylated (palmitoylated) in vitro and in amyotrophic lateral sclerosis (ALS) mouse models, and that S-acylation increased for ALS-causing SOD1 mutants relative to wild type. Here, we use the acyl resin-assisted capture (acyl-RAC) assay to demonstrate S-acylation of SOD1 in human post-mortem spinal cord homogenates from ALS and non-ALS subjects. Acyl-RAC further revealed that endogenous copper chaperone for SOD1 (CCS) is S-acylated in both human and mouse spinal cords, and in vitro in HEK293 cells. SOD1 and CCS formed a highly stable heterodimer in human spinal cord homogenates that was resistant to dissociation by boiling, denaturants, or reducing agents and was not observed in vitro unless both SOD1 and CCS were overexpressed. Cysteine mutations that attenuate SOD1 maturation prevented the SOD1-CCS heterodimer formation. The degree of S-acylation was highest for SOD1-CCS heterodimers, intermediate for CCS monomers, and lowest for SOD1 monomers. Given that S-acylation facilitates anchoring of soluble proteins to cell membranes, our findings suggest that S-acylation and membrane localization may play an important role in CCS-mediated SOD1 maturation. Furthermore, the highly stable S-acylated SOD1-CCS heterodimer may serve as a long-lived maturation intermediate in human spinal cord. PMID:28120938

Molecular Cloning, Characterization and Predicted Structure of a Putative Copper-Zinc SOD from the Camel, Camelus dromedarius

PubMed Central

Ataya, Farid S.; Fouad, Dalia; Al-Olayan, Ebtsam; Malik, Ajamaluddin

2012-01-01

Superoxide dismutase (SOD) is the first line of defense against oxidative stress induced by endogenous and/or exogenous factors and thus helps in maintaining the cellular integrity. Its activity is related to many diseases; so, it is of importance to study the structure and expression of SOD gene in an animal naturally exposed most of its life to the direct sunlight as a cause of oxidative stress. Arabian camel (one humped camel, Camelus dromedarius) is adapted to the widely varying desert climatic conditions that extremely changes during daily life in the Arabian Gulf. Studying the cSOD1 in C. dromedarius could help understand the impact of exposure to direct sunlight and desert life on the health status of such mammal. The full coding region of a putative CuZnSOD gene of C. dromedarius (cSOD1) was amplified by reverse transcription PCR and cloned for the first time (gene bank accession number for nucleotides and amino acids are JF758876 and AEF32527, respectively). The cDNA sequencing revealed an open reading frame of 459 nucleotides encoding a protein of 153 amino acids which is equal to the coding region of SOD1 gene and protein from many organisms. The calculated molecular weight and isoelectric point of cSOD1 was 15.7 kDa and 6.2, respectively. The level of expression of cSOD1 in different camel tissues (liver, kidney, spleen, lung and testis) was examined using Real Time-PCR. The highest level of cSOD1 transcript was found in the camel liver (represented as 100%) followed by testis (45%), kidney (13%), lung (11%) and spleen (10%), using 18S ribosomal subunit as endogenous control. The deduced amino acid sequence exhibited high similarity with Cebus apella (90%), Sus scrofa (88%), Cavia porcellus (88%), Mus musculus (88%), Macaca mulatta (87%), Pan troglodytes (87%), Homo sapiens (87%), Canis familiaris (86%), Bos taurus (86%), Pongo abelii (85%) and Equus caballus (82%). Phylogenetic analysis revealed that cSOD1 is grouped together with S. scrofa. The predicted 3D structure of cSOD1 showed high similarity with the human and bovine CuZnSOD homologues. The Root-mean-square deviation (rmsd) between cSOD1/hSOD1 and cSOD1/bSOD1 superimposed structure pairs were 0.557 and 0.425 A. The Q-score of cSOD1-hSOD1 and cSOD1-bSOD1 were 0.948 and 0.961, respectively. PMID:22312292

Differential Expression of Superoxide Dismutase Genes in Aphid-Stressed Maize (Zea mays L.) Seedlings

PubMed Central

Sytykiewicz, Hubert

2014-01-01

The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB) in seedling leaves of the Zea mays L. Tasty Sweet (susceptible) and Ambrozja (relatively resistant) cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid) or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid). Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl) radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9). However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4) or 24 h (sod9) post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants. PMID:24722734

Differential expression of superoxide dismutase genes in aphid-stressed maize (Zea mays L.) seedlings.

PubMed

Sytykiewicz, Hubert

2014-01-01

The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB) in seedling leaves of the Zea mays L. Tasty Sweet (susceptible) and Ambrozja (relatively resistant) cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid) or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid). Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl) radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9). However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4) or 24 h (sod9) post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants.

In yeast redistribution of Sod1 to the mitochondrial intermembrane space provides protection against respiration derived oxidative stress.

PubMed

Klöppel, Christine; Michels, Christine; Zimmer, Julia; Herrmann, Johannes M; Riemer, Jan

2010-12-03

The antioxidative enzyme copper-zinc superoxide dismutase (Sod1) is an important cellular defence system against reactive oxygen species (ROS). While the majority of this enzyme is localized to the cytosol, about 1% of the cellular Sod1 is present in the intermembrane space (IMS) of mitochondria. These amounts of mitochondrial Sod1 are increased for certain Sod1 mutants that are linked to the neurodegenerative disease amyotrophic lateral sclerosis (ALS). To date, only little is known about the physiological function of mitochondrial Sod1. Here, we use the model system Saccharomyces cerevisiae to generate cells in which Sod1 is exclusively localized to the IMS. We find that IMS-localized Sod1 can functionally substitute wild type Sod1 and that it even exceeds the protective capacity of wild type Sod1 under conditions of mitochondrial ROS stress. Moreover, we demonstrate that upon expression in yeast cells the common ALS-linked mutant Sod1(G93A) becomes enriched in the mitochondrial fraction and provides an increased protection of cells from mitochondrial oxidative stress. Such an effect cannot be observed for the catalytically inactive mutant Sod1(G85R). Our observations suggest that the targeting of Sod1 to the mitochondrial IMS provides an increased protection against respiration-derived ROS. Copyright © 2010 Elsevier Inc. All rights reserved.

Alterations of the levels of primary antioxidant enzymes in different grades of human astrocytoma tissues.

PubMed

Yen, Hsiu-Chuan; Lin, Chih-Lung; Chen, Bing-Shian; Chen, Chih-Wei; Wei, Kuo-Chen; Yang, Mei-Lin; Hsu, Jee-Ching; Hsu, Yung-Hsing

2018-06-03

Malignant astrocytoma is the most commonly occurring brain tumor in humans. Oxidative stress is implicated in the development of cancers. Superoxide dismutase 2 (SOD2) was found to exert tumor suppressive effect in basic research, but increased SOD2 protein level was associated with higher aggressiveness of human astrocytomas. However, studies reporting alterations of antioxidant enzymes in human astrocytomas often employed less accurate methods or included different types of tumors. Here we analyzed the mRNA levels, activities, and protein levels of primary antioxidant enzymes in control brain tissues and various grades of astrocytomas obtained from 40 patients. SOD1 expression, SOD1 activity, and SOD1 protein level were lower in Grade IV astrocytomas. SOD2 expression was lower in low-grade (Grades I and II) and Grade III astrocytomas than in controls, but SOD2 expression and SOD2 protein level were higher in Grade IV astrocytomas than in Grade III astrocytomas. Although there was no change in SOD2 activity and a lower activity of citrate synthase (CS), the MnSOD:CS ratio increased in Grade IV astrocytomas compared with controls and low-grade astrocytomas. Furthermore, SOD1 activity, CS activity, SOD1 expression, GPX4 expression, and GPX4 protein level were inversely correlated with the malignancy, whereas catalase activity, catalase protein, SOD2 protein level, and the SOD2:CS ratio were positively correlated with the degree of malignancy. Lower SOD2:CS ratio was associated with poor outcomes for Grade IV astrocytomas. This is the first study to quantify changes of various primary antioxidant enzymes in different grades of astrocytomas at different levels concurrently in human astrocytomas.

Reduced mitochondrial SOD displays mortality characteristics reminiscent of natural aging

PubMed Central

Paul, Anirban; Belton, Amy; Nag, Sanjay; Martin, Ian; Grotewiel, Michael S.; Duttaroy, Atanu

2009-01-01

Manganese superoxide dismutase (MnSOD or SOD2) is a key mitochondrial enzymatic antioxidant. Arguably the most striking phenotype associated with complete loss of SOD2 in flies and mice is shortened life span. To further explore the role of SOD2 in protecting animals from aging and age-associated pathology, we generated a unique collection of Drosophila mutants that progressively reduce SOD2 expression and function. Mitochondrial aconitase activity was substantially reduced in the Sod2 mutants, suggesting that SOD2 normally ensures the functional capacity of mitochondria. Flies with severe reductions in SOD2 expression exhibited accelerated senescence of olfactory behavior as well as precocious neurodegeneration and DNA strand breakage in neurons. Furthermore, life span was progressively shortened and age-dependent mortality was increased in conjunction with reduced SOD2 expression, while initial mortality and developmental viability were unaffected. Interestingly, life span and age-dependent mortality varied exponentially with SOD2 activity, indicating that there might normally be a surplus of this enzyme for protecting animals from premature death. Our data support a model in which disruption of the protective effects of SOD2 on mitochondria manifests as profound changes in behavioral and demographic aging as well as exacerbated age-related pathology in the nervous system. PMID:18078670

A role for Candida albicans superoxide dismutase enzymes in glucose signaling.

PubMed

Broxton, Chynna N; He, Bixi; Bruno, Vincent M; Culotta, Valeria C

2018-01-01

The Saccharomyces cerevisiae and Candida albicans yeasts have evolved to differentially use glucose for fermentation versus respiration. S. cerevisiae is Crabtree positive, where glucose represses respiration and promotes fermentation, while the opportunistic fungal pathogen C. albicans is Crabtree negative and does not repress respiration with glucose. We have previously shown that glucose control in S. cerevisiae involves the antioxidant enzyme Cu/Zn superoxide dismutase (SOD1), where H 2 O 2 generated by SOD1 stabilizes the casein kinase YCK1 for glucose sensing. We now demonstrate that C. albicans SODs also participate in glucose regulation. C. albicans expresses two cytosolic SODs, Cu/Zn SOD1 and Mn containing SOD3, and both complemented a S. cerevisiae sod1Δ mutant in stabilizing YCK1. Moreover, in C. albicans cells, both SODs functioned to repress glucose transporter genes in response to glucose. However, the action of SODs in glucose control has diverged in the two yeasts. In S. cerevisiae, SOD1 specifically functions in the glucose sensing pathway involving YCK1 and the RGT1 repressor, but the analogous YCK/RGT1 pathway in C. albicans shows no control by SOD enzymes. Instead C. albicans SODs work in the glucose repression pathway involving the MIG1 transcriptional repressor. In C. albicans, the SODs repress glucose uptake, while in S. cerevisiae, SOD1 activates glucose uptake, in accordance with the divergent modes for glucose utilization in these two distantly related yeasts. Copyright © 2017 Elsevier Inc. All rights reserved.

SOD1 oxidation and formation of soluble aggregates in yeast: Relevance to sporadic ALS development

PubMed Central

Martins, Dorival; English, Ann M.

2014-01-01

Misfolding and aggregation of copper–zinc superoxide dismutase (Sod1) are observed in neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). Mutations in Sod1 lead to familial ALS (FALS), which is a late-onset disease. Since oxidative damage to proteins increases with age, it had been proposed that oxidation of Sod1 mutants may trigger their misfolding and aggregation in FALS. However, over 90% of ALS cases are sporadic (SALS) with no obvious genetic component. We hypothesized that oxidation could also trigger the misfolding and aggregation of wild-type Sod1 and sought to confirm this in a cellular environment. Using quiescent, stationary-phase yeast cells as a model for non-dividing motor neurons, we probed for post-translational modification (PTM) and aggregation of wild-type Sod1 extracted from these cells. By size-exclusion chromatography (SEC), we isolated two populations of Sod1 from yeast: a low-molecular weight (LMW) fraction that is catalytically active and a catalytically inactive, high-molecular weight (HMW) fraction. High-resolution mass spectrometric analysis revealed that LMW Sod1 displays no PTMs but HMW Sod1 is oxidized at Cys146 and His71, two critical residues for the stability and folding of the enzyme. HMW Sod1 is also oxidized at His120, a copper ligand, which will promote loss of this catalytic metal cofactor essential for SOD activity. Monitoring the fluorescence of a Sod1-green-fluorescent-protein fusion (Sod1-GFP) extracted from yeast chromosomally expressing this fusion, we find that HMW Sod1-GFP levels increase up to 40-fold in old cells. Thus, we speculate that increased misfolding and inclusion into soluble aggregates is a consequence of elevated oxidative modifications of wild-type Sod1 as cells age. Our observations argue that oxidative damage to wild-type Sod1 initiates the protein misfolding mechanisms that give rise to SALS. PMID:24936435

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

PubMed

Gamero-Sandemetrio, Esther; Gómez-Pastor, Rocío; Matallana, Emilia

2017-01-01

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 H 2 O 2 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.

cIAPs promote the proteasomal degradation of mutant SOD1 linked to familial amyotrophic lateral sclerosis.

PubMed

Choi, Jin Sun; Kim, Kidae; Lee, Do Hee; Cho, Sayeon; Ha, Jae Du; Park, Byoung Chul; Kim, Sunhong; Park, Sung Goo; Kim, Jeong-Hoon

2016-11-18

Although the ubiquitin-proteasome system is believed to play an important role in the pathogenesis of familial amyotrophic lateral sclerosis (FALS), caused by mutations in Cu/Zn-superoxide dismutase 1 (SOD1), the mechanism of how mutant SOD1 protein is regulated in cells is still poorly understood. Here we have demonstrated that cellular inhibitor of apoptosis proteins (cIAPs) are specifically associated with FALS-linked mutant SOD1 (mSOD1) and that this interaction promotes the ubiquitin-dependent proteasomal degradation of mutant SOD1. By utilizing cumate inducible SOD1 cells, we also showed that knock-down or pharmacologic depletion of cIAPs leads to H 2 O 2 induced cytotoxicity in mSOD1 expressing cells. Altogether, our results reveal a novel role of cIAPs in FALS-associated mutant SOD1 regulation. Copyright © 2016 Elsevier Inc. All rights reserved.

Eukaryotic copper-only superoxide dismutases (SODs): A new class of SOD enzymes and SOD-like protein domains.

PubMed

Robinett, Natalie G; Peterson, Ryan L; Culotta, Valeria C

2018-03-30

The copper-containing superoxide dismutases (SODs) represent a large family of enzymes that participate in the metabolism of reactive oxygen species by disproportionating superoxide anion radical to oxygen and hydrogen peroxide. Catalysis is driven by the redox-active copper ion, and in most cases, SODs also harbor a zinc at the active site that enhances copper catalysis and stabilizes the protein. Such bimetallic Cu,Zn-SODs are widespread, from the periplasm of bacteria to virtually every organelle in the human cell. However, a new class of copper-containing SODs has recently emerged that function without zinc. These copper-only enzymes serve as extracellular SODs in specific bacteria ( i.e. Mycobacteria), throughout the fungal kingdom, and in the fungus-like oomycetes. The eukaryotic copper-only SODs are particularly unique in that they lack an electrostatic loop for substrate guidance and have an unusual open-access copper site, yet they can still react with superoxide at rates limited only by diffusion. Copper-only SOD sequences similar to those seen in fungi and oomycetes are also found in the animal kingdom, but rather than single-domain enzymes, they appear as tandem repeats in large polypeptides we refer to as CSRPs (copper-only SOD-repeat proteins). Here, we compare and contrast the Cu,Zn versus copper-only SODs and discuss the evolution of copper-only SOD protein domains in animals and fungi. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Inhibitory effect on the proliferation of human heptoma induced by cell-permeable manganese superoxide dismutase.

PubMed

Guo, Hua; Zhang, Na; Liu, Di; Wang, Ping; Ma, Xingyuan

2016-10-01

Mitochondrial antioxidant manganese superoxide dismutase (MnSOD) belongs to a group of genes whose expression is generally decreased significantly in patients with hepatoma. The proliferation of cancer cells with low expression of MnSOD exhibit high sensitivity to the elevated expression of MnSOD. However, due to the lack of ability to penetrate the cell membrane, the direct use and study of SOD for cancer treatment are largely hampered. In this work, cell penetrating peptide TAT was fused to the N-terminus of MnSOD to facilitate the penetration of MnSOD through cell membranes. Results showed that TAT-MnSOD wt treatment induced evident inhibitory effect on the proliferation of heptoma, with minimal effect on normal cells. It was further demonstrated that both the penetration of cells and enzymatic activity of MnSOD are essential to its inhibitory function, because only TAT-MnSOD wt, not inactive TAT-MnSOD mutant or MnSOD could successfully inhibit cell proliferation and reduce the intra-celluar reactive oxygen species (ROS). In addition, the lower oxidative stress delayed the cell cycle at G2/M and significantly slowed HepG2 cell growth in association with the dephosphorylation of survivin. Our results help in understanding the regulatory effects of MnSOD on cell viability and redox homestasis of heptoma and promise potential applications of TAT-MnSOD wt for clinical cancer therapy. Copyright © 2016. Published by Elsevier Masson SAS.

[The level of superoxide dismutase expression in primary and metastatic colorectal cancer cells in hypoxia and tissue normoxia].

PubMed

Skrzycki, Michał; Czeczot, Hanna; Chrzanowska, Alicja; Otto-Ślusarczyk, Dagmara

2015-11-01

Superoxide oxidase (SOD) is a key antioxidant enzyme protecting cells against oxidative stress, which might induce cancerogenesis. In tumor cells SOD influences the level of the reactive oxygen species (ROS) allowing for survival and proliferation. High rate of cells proliferation in tumor leads to their temporary hypoxia due to lower rate of angiogenesis. Therefore during tumor development, cancer cells function in conditions of hypoxia or tissue normoxia. The aim of study was to evaluate of SOD isoenzymes (SOD1 and SOD2) expression level in cell lines of primary (SW 480) and metastatic (SW 620) colorectal cancer, cultured in hypoxia (1% oxygen), tissue normoxia (10% oxygen), and atmospheric normoxia (21% oxygen). Cells were cultured in MEM medium in different oxygen concentrations (1%, 10%, 21%) in hypoxic chamber with oxygenation regulator. The number of living cells in lines SW 480 and 620 was determined by trypan blue method. Expression of SOD1 and SOD2 at the mRNA level was determined by RT-PCR and PCR. In both studied cell lines (SW 480 and SW 620), the number of living cells (viability) was increased in hypoxia and atmospheric normoxia. The expression level of SOD1 and SOD2 in studied cell lines was different. The lowest level of expression of both SOD isoenzymes was observed in hypoxia. In conditions of atmospheric normoxia the expression level of SOD1 in SW480 cell line was increased, and similar in SW620 cell line comparing to tissue normoxia. Whereas the SOD2 expression level in atmospheric normoxia conditions in both cell lines was significantly increased. Observed differences were statistically significant (p ≤ 0,05). The profile of expression of SOD1 and SOD2 in cell lines SW480 and SW620 indicates differentiated response of tumor cells depending on access to oxygen. Low level of SOD isoenzymes expression in SW480 and SW620 cells in hypoxia indicates decreased production of ROS. Differences of SOD isoenzymes expression level in tissue normoxia indicate their compensatory action, allowing to maintain the balance between O₂- removal and H₂O₂production in studied tumor cells. In atmospheric normoxia conditions increased expression level of SOD1 and SOD2 observed in studied cell lines points to oxidative stress. © 2015 MEDPRESS.

Activation of Cu,Zn-superoxide dismutase in the absence of oxygen and the copper chaperone CCS.

PubMed

Leitch, Jeffry M; Jensen, Laran T; Bouldin, Samantha D; Outten, Caryn E; Hart, P John; Culotta, Valeria C

2009-08-14

Eukaryotic Cu,Zn-superoxide dismutases (SOD1s) are generally thought to acquire the essential copper cofactor and intramolecular disulfide bond through the action of the CCS copper chaperone. However, several metazoan SOD1s have been shown to acquire activity in vivo in the absence of CCS, and the Cu,Zn-SOD from Caenorhabditis elegans has evolved complete independence from CCS. To investigate SOD1 activation in the absence of CCS, we compared and contrasted the CCS-independent activation of C. elegans and human SOD1 to the strict CCS-dependent activation of Saccharomyces cerevisiae SOD1. Using a yeast expression system, both pathways were seen to acquire copper derived from cell surface transporters and compete for the same intracellular pool of copper. Like CCS, CCS-independent activation occurs rapidly with a preexisting pool of apo-SOD1 without the need for new protein synthesis. The two pathways, however, strongly diverge when assayed for the SOD1 disulfide. SOD1 molecules that are activated without CCS exhibit disulfide oxidation in vivo without oxygen and under copper-depleted conditions. The strict requirement for copper, oxygen, and CCS in disulfide bond oxidation appears exclusive to yeast SOD1, and we find that a unique proline at position 144 in yeast SOD1 is responsible for this disulfide effect. CCS-dependent and -independent pathways also exhibit differential requirements for molecular oxygen. CCS activation of SOD1 requires oxygen, whereas the CCS-independent pathway is able to activate SOD1s even under anaerobic conditions. In this manner, Cu,Zn-SOD from metazoans may retain activity over a wide range of physiological oxygen tensions.

An Analysis of Interactions between Fluorescently-Tagged Mutant and Wild-Type SOD1 in Intracellular Inclusions

PubMed Central

Qualls, David A.; Crosby, Keith; Brown, Hilda; Borchelt, David R.

2013-01-01

Background By mechanisms yet to be discerned, the co-expression of high levels of wild-type human superoxide dismutase 1 (hSOD1) with variants of hSOD1 encoding mutations linked familial amyotrophic lateral sclerosis (fALS) hastens the onset of motor neuron degeneration in transgenic mice. Although it is known that spinal cords of paralyzed mice accumulate detergent insoluble forms of WT hSOD1 along with mutant hSOD1, it has been difficult to determine whether there is co-deposition of the proteins in inclusion structures. Methodology/Principal Findings In the present study, we use cell culture models of mutant SOD1 aggregation, focusing on the A4V, G37R, and G85R variants, to examine interactions between WT-hSOD1 and misfolded mutant SOD1. In these studies, we fuse WT and mutant proteins to either yellow or red fluorescent protein so that the two proteins can be distinguished within inclusions structures. Conclusions/Significance Although the interpretation of the data is not entirely straightforward because we have strong evidence that the nature of the fused fluorophores affects the organization of the inclusions that form, our data are most consistent with the idea that normal dimeric WT-hSOD1 does not readily interact with misfolded forms of mutant hSOD1. We also demonstrate the monomerization of WT-hSOD1 by experimental mutation does induce the protein to aggregate, although such monomerization may enable interactions with misfolded mutant SOD1. Our data suggest that WT-hSOD1 is not prone to become intimately associated with misfolded mutant hSOD1 within intracellular inclusions that can be generated in cultured cells. PMID:24391857

Extracellular Superoxide Dismutase Deficiency Exacerbates Pressure Overload–Induced Left Ventricular Hypertrophy and Dysfunction

PubMed Central

Lu, Zhongbing; Xu, Xin; Hu, Xinli; Zhu, Guangshuo; Zhang, Ping; van Deel, Elza D.; French, Joel P.; Fassett, John T.; Oury, Tim D.; Bache, Robert J.; Chen, Yingjie

2008-01-01

Extracellular superoxide dismutase (SOD) contributes only a small fraction to total SOD activity in the normal heart but is strategically located to scavenge free radicals in the extracellular compartment. To examine the physiological significance of extracellular SOD in the response of the heart to hemodynamic stress, we studied the effect of extracellular SOD deficiency on transverse aortic constriction (TAC)–induced left ventricular remodeling. Under unstressed conditions extracellular SOD deficiency had no effect on myocardial total SOD activity, the ratio of glutathione:glutathione disulfide, nitrotyrosine content, or superoxide anion production but resulted in small but significant increases in myocardial fibrosis and ventricular mass. In response to TAC for 6 weeks, extracellular SOD-deficient mice developed more severe left ventricular hypertrophy (heart weight increased 2.56-fold in extracellular SOD-deficient mice as compared with 1.99-fold in wild-type mice) and pulmonary congestion (lung weight increased 2.92-fold in extracellular SOD-deficient mice as compared with 1.84-fold in wild-type mice). Extracellular SOD-deficient mice also had more ventricular fibrosis, dilation, and a greater reduction of left ventricular fractional shortening and rate of pressure development after TAC. TAC resulted in greater increases of ventricular collagen I, collagen III, matrix metalloproteinase-2, matrix metalloproteinase-9, nitrotyrosine, and superoxide anion production. TAC also resulted in a greater decrease of the ratio of glutathione:glutathione disulfide in extracellular SOD-deficient mice. The finding that extracellular SOD deficiency had minimal impact on myocardial overall SOD activity but exacerbated TAC induced myocardial oxidative stress, hypertrophy, fibrosis, and dysfunction indicates that the distribution of extracellular SOD in the extracellular space is critically important in protecting the heart against pressure overload. PMID:17998475

Role of antioxidant enzymes in redox regulation of N-methyl-D-aspartate receptor function and memory in middle-aged rats.

PubMed

Lee, Wei-Hua; Kumar, Ashok; Rani, Asha; Foster, Thomas C

2014-06-01

Overexpression of superoxide dismutase 1 (SOD1) in the hippocampus results in age-dependent impaired cognition and altered synaptic plasticity suggesting a possible model for examining the role of oxidative stress in senescent neurophysiology. However, it is unclear if SOD1 overexpression involves an altered redox environment and a decrease in N-methyl-D-aspartate receptor (NMDAR) synaptic function reported for aging animals. Viral vectors were used to express SOD1 and green fluorescent protein (SOD1 + GFP), SOD1 and catalase (SOD1 + CAT), or GFP alone in the hippocampus of middle-aged (17 months) male Fischer 344 rats. We confirm that SOD1 + GFP and SOD1 + CAT reduced lipid peroxidation indicating superoxide metabolites were primarily responsible for lipid peroxidation. SOD1 + GFP impaired learning, decreased glutathione peroxidase activity, decreased glutathione levels, decreased NMDAR-mediated synaptic responses, and impaired long-term potentiation. Co-expression of SOD1 + CAT rescued the effects of SOD1 expression on learning, redox measures, and synaptic function suggesting the effects were mediated by excess hydrogen peroxide. Application of the reducing agent dithiolthreitol to hippocampal slices increased the NMDAR-mediated component of the synaptic response in SOD1 + GFP animals relative to animals that overexpress SOD1 + CAT indicating that the effect of antioxidant enzyme expression on NMDAR function was because of a shift in the redox environment. The results suggest that overexpression of neuronal SOD1 and CAT in middle age may provide a model for examining the role of oxidative stress in senescent physiology and the progression of age-related neurodegenerative diseases. Copyright © 2014 Elsevier Inc. All rights reserved.

A correlation of reactive oxygen species accumulation by depletion of superoxide dismutases with age-dependent impairment in the nervous system and muscles of Drosophila adults.

PubMed

Oka, Saori; Hirai, Jun; Yasukawa, Takashi; Nakahara, Yasuyuki; Inoue, Yoshihiro H

2015-08-01

The theory that accumulation of reactive oxygen species (ROS) in internal organs is a major promoter of aging has been considered negatively. However, it is still controversial whether overexpression of superoxide dismutases (SODs), which remove ROS, extends the lifespan in Drosophila adults. We examined whether ROS accumulation by depletion of Cu/Zn-SOD (SOD1) or Mn-SOD (SOD2) influenced age-related impairment of the nervous system and muscles in Drosophila. We confirmed the efficient depletion of Sod1 and Sod2 through RNAi and ROS accumulation by monitoring of ROS-inducible gene expression. Both RNAi flies displayed accelerated impairment of locomotor activity with age and shortened lifespan. Similarly, adults with nervous system-specific depletion of Sod1 or Sod2 also showed reduced lifespan. We then found an accelerated loss of dopaminergic neurons in the flies with suppressed SOD expression. A half-dose reduction of three pro-apoptotic genes resulted in a significant suppression of the neuronal loss, suggesting that apoptosis was involved in the neuronal loss caused by SOD silencing. In addition, depletion of Sod1 or Sod2 in musculature is also associated with enhancement of age-related locomotion impairment. In indirect flight muscles from SOD-depleted adults, abnormal protein aggregates containing poly-ubiquitin accumulated at an early adult stage and continued to increase as the flies aged. Most of these protein aggregates were observed between myofibril layers. Moreover, immuno-electron microscopy indicated that the aggregates were predominantly localized in damaged mitochondria. These findings suggest that muscular and neuronal ROS accumulation may have a significant effect on age-dependent impairment of the Drosophila adults.

Molecular chaperone mediated late-stage neuroprotection in the SOD1(G93A) mouse model of amyotrophic lateral sclerosis.

PubMed

Novoselov, Sergey S; Mustill, Wendy J; Gray, Anna L; Dick, James R; Kanuga, Naheed; Kalmar, Bernadett; Greensmith, Linda; Cheetham, Michael E

2013-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the selective loss of motor neurons in the spinal cord, brain stem, and motor cortex. Mutations in superoxide dismutase (SOD1) are associated with familial ALS and lead to SOD1 protein misfolding and aggregation. Here we show that the molecular chaperone, HSJ1 (DNAJB2), mutations in which cause distal hereditary motor neuropathy, can reduce mutant SOD1 aggregation and improve motor neuron survival in mutant SOD1 models of ALS. Overexpression of human HSJ1a (hHSJ1a) in vivo in motor neurons of SOD1(G93A) transgenic mice ameliorated disease. In particular, there was a significant improvement in muscle force, increased motor unit number and enhanced motor neuron survival. hHSJ1a was present in a complex with SOD1(G93A) and led to reduced SOD1 aggregation at late stages of disease progression. We also observed altered ubiquitin immunoreactivity in the double transgenic animals, suggesting that ubiquitin modification might be important for the observed improvements. In a cell model of SOD1(G93A) aggregation, HSJ1a preferentially bound to mutant SOD1, enhanced SOD1 ubiquitylation and reduced SOD1 aggregation in a J-domain and ubiquitin interaction motif (UIM) dependent manner. Collectively, the data suggest that HSJ1a acts on mutant SOD1 through a combination of chaperone, co-chaperone and pro-ubiquitylation activity. These results show that targeting SOD1 protein misfolding and aggregation in vivo can be neuroprotective and suggest that manipulation of DnaJ molecular chaperones might be useful in the treatment of ALS.

ATM is required for SOD2 expression and homeostasis within the mammary gland.

PubMed

Dyer, Lisa M; Kepple, Jessica D; Ai, Lingbao; Kim, Wan-Ju; Stanton, Virginia L; Reinhard, Mary K; Backman, Lindsey R F; Streitfeld, W Scott; Babu, Nivetha Ramesh; Treiber, Nicolai; Scharffetter-Kochanek, Karin; McKinnon, Peter J; Brown, Kevin D

2017-12-01

ATM activates the NF-κB transcriptional complex in response to genotoxic and oxidative stress. The purpose of this study was to examine if the NF-κB target gene and critical antioxidant SOD2 (MnSOD) in cultured mammary epithelium is also ATM-dependent, and what phenotypes arise from deletion of ATM and SOD2 within the mammary gland. SOD2 expression was studied in human mammary epithelial cells and MCF10A using RNAi to knockdown ATM or the NF-κB subunit RelA. To study ATM and SOD2 function in mammary glands, mouse lines containing Atm or Sod2 genes containing LoxP sites were mated with mice harboring Cre recombinase under the control of the whey acidic protein promoter. Quantitative PCR was used to measure gene expression, and mammary gland structure was studied using histology. SOD2 expression is ATM- and RelA-dependent, ATM knockdown renders cells sensitive to pro-oxidant exposure, and SOD mimetics partially rescue this sensitivity. Mice with germline deletion of Atm fail to develop mature mammary glands, but using a conditional knockout approach, we determined that Atm deletion significantly diminished the expression of Sod2. We also observed that these mice (termed Atm Δ/Δ ) displayed a progressive lactation defect as judged by reduced pup growth rate, aberrant lobulo-alveolar structure, diminished milk protein gene expression, and increased apoptosis within lactating glands. This phenotype appears to be linked to dysregulated Sod2 expression as mammary gland-specific deletion of Sod2 phenocopies defects observed in Atm Δ/Δ dams. We conclude that ATM is required to promote expression of SOD2 within the mammary epithelium, and that both ATM and SOD2 play a crucial role in mammary gland homeostasis.

Mechanisms for activating Cu- and Zn-containing superoxide dismutase in the absence of the CCS Cu chaperone.

PubMed

Carroll, Mark C; Girouard, Jody B; Ulloa, Janella L; Subramaniam, Jamuna R; Wong, Phillip C; Valentine, Joan Selverstone; Culotta, Valeria Cizewski

2004-04-20

The Cu- and Zn-containing superoxide dismutase 1 (SOD1) largely obtains Cu in vivo by means of the action of the Cu chaperone CCS. Yet, in the case of mammalian SOD1, a secondary pathway of activation is apparent. Specifically, when human SOD1 is expressed in either yeast or mammalian cells that are null for CCS, the SOD1 enzyme retains a certain degree of activity. This CCS-independent activity is evident with both wild-type and mutant variants of SOD1 that have been associated with familial amyotrophic lateral sclerosis. We demonstrate here that the CCS-independent activation of mammalian SOD1 involves glutathione, particularly the reduced form, or GSH. A role for glutathione in CCS-independent activation was seen with human SOD1 molecules that were expressed in either yeast cells or immortalized fibroblasts. Compared with mammalian SOD1, the Saccharomyces cerevisiae enzyme cannot obtain Cu without CCS in vivo, and this total dependence on CCS involves the presence of dual prolines near the C terminus of the SOD1 polypeptide. Indeed, the insertion of such prolines into human SOD1 rendered this molecule refractory to CCS-independent activation. The possible implications of multiple pathways for SOD1 activation are discussed in the context of SOD1 evolutionary biology and familial amyotrophic lateral sclerosis.

A molecular chaperone activity of CCS restores the maturation of SOD1 fALS mutants.

PubMed

Luchinat, Enrico; Barbieri, Letizia; Banci, Lucia

2017-12-12

Superoxide dismutase 1 (SOD1) is an important metalloprotein for cellular oxidative stress defence, that is mutated in familiar variants of Amyotrophic Lateral Sclerosis (fALS). Some mutations destabilize the apo protein, leading to the formation of misfolded, toxic species. The Copper Chaperone for SOD1 (CCS) transiently interacts with SOD1 and promotes its correct maturation by transferring copper and catalyzing disulfide bond formation. By in vitro and in-cell NMR, we investigated the role of the SOD-like domain of CCS (CCS-D2). We showed that CCS-D2 forms a stable complex with zinc-bound SOD1 in human cells, that has a twofold stabilizing effect: it both prevents the accumulation of unstructured mutant SOD1 and promotes zinc binding. We further showed that CCS-D2 interacts with apo-SOD1 in vitro, suggesting that in cells CCS stabilizes mutant apo-SOD1 prior to zinc binding. Such molecular chaperone function of CCS-D2 is novel and its implications in SOD-linked fALS deserve further investigation.

Structures of the G85R Variant of SOD1 in Familial Amyotrophic Lateral Sclerosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, Xiaohang; Antonyuk, Svetlana V.; Seetharaman, Sai V.

2008-07-21

Mutations in the gene encoding human copper-zinc superoxide dismutase (SOD1) cause a dominant form of the progressive neurodegenerative disease amyotrophic lateral sclerosis. Transgenic mice expressing the human G85R SOD1 variant develop paralytic symptoms concomitant with the appearance of SOD1-enriched proteinaceous inclusions in their neural tissues. The process(es) through which misfolding or aggregation of G85R SOD1 induces motor neuron toxicity is not understood. Here we present structures of the human G85R SOD1 variant determined by single crystal x-ray diffraction. Alterations in structure of the metal-binding loop elements relative to the wild type enzyme suggest a molecular basis for the metal ionmore » deficiency of the G85R SOD1 protein observed in the central nervous system of transgenic mice and in purified recombinant G85R SOD1. These findings support the notion that metal-deficient and/or disulfide-reduced mutant SOD1 species contribute to toxicity in SOD1-linked amyotrophic lateral sclerosis.« less

Transcriptional and phenotypic changes in aorta and aortic valve with aging and MnSOD deficiency in mice

PubMed Central

Roos, Carolyn M.; Hagler, Michael; Zhang, Bin; Oehler, Elise A.; Arghami, Arman

2013-01-01

The purpose of this study was to characterize changes in antioxidant and age-related gene expression in aorta and aortic valve with aging, and test the hypothesis that increased mitochondrial oxidative stress accelerates age-related endothelial and aortic valve dysfunction. Wild-type (MnSOD+/+) and manganese SOD heterozygous haploinsufficient (MnSOD+/−) mice were studied at 3 and 18 mo of age. In aorta from wild-type mice, antioxidant expression was preserved, although there were age-associated increases in Nox2 expression. Haploinsufficiency of MnSOD did not alter antioxidant expression in aorta, but increased expression of Nox2. When compared with that of aorta, age-associated reductions in antioxidant expression were larger in aortic valves from wild-type and MnSOD haploinsufficient mice, although Nox2 expression was unchanged. Similarly, sirtuin expression was relatively well-preserved in aorta from both genotypes, whereas expression of SIRT1, SIRT2, SIRT3, SIRT4, and SIRT6 were significantly reduced in the aortic valve. Expression of p16ink4a, a marker of cellular senescence, was profoundly increased in both aorta and aortic valve from MnSOD+/+ and MnSOD+/− mice. Functionally, we observed comparable age-associated reductions in endothelial function in aorta from both MnSOD+/+ and MnSOD+/− mice. Interestingly, inhibition of NAD(P)H oxidase with apocynin or gp91ds-tat improved endothelial function in MnSOD+/+ mice but significantly impaired endothelial function in MnSOD+/− mice at both ages. Aortic valve function was not impaired by aging or MnSOD haploinsufficiency. Changes in antioxidant and sirtuin gene expression with aging differ dramatically between aorta and aortic valve. Furthermore, although MnSOD does not result in overt cardiovascular dysfunction with aging, compensatory transcriptional responses to MnSOD deficiency appear to be tissue specific. PMID:23997094

Pyrimethamine significantly lowers cerebrospinal fluid Cu/Zn superoxide dismutase in amyotrophic lateral sclerosis patients with SOD1 mutations.

PubMed

Lange, Dale J; Shahbazi, Mona; Silani, Vincenzo; Ludolph, Albert C; Weishaupt, Jochen H; Ajroud-Driss, Senda; Fields, Kara G; Remanan, Rahul; Appel, Stanley H; Morelli, Claudia; Doretti, Alberto; Maderna, Luca; Messina, Stefano; Weiland, Ulrike; Marklund, Stefan L; Andersen, Peter M

2017-06-01

Cu/Zn superoxide dismutase (SOD1) reduction prolongs survival in SOD1-transgenic animal models. Pyrimethamine produces dose-dependent SOD1 reduction in cell culture systems. A previous phase 1 trial showed pyrimethamine lowers SOD1 levels in leukocytes in patients with SOD1 mutations. This study investigated whether pyrimethamine lowered SOD1 levels in the cerebrospinal fluid (CSF) in patients carrying SOD1 mutations linked to familial amyotrophic lateral sclerosis (fALS/SOD1). A multicenter (5 sites), open-label, 9-month-duration, dose-ranging study was undertaken to determine the safety and efficacy of pyrimethamine to lower SOD1 levels in the CSF in fALS/SOD1. All participants underwent 3 lumbar punctures, blood draw, clinical assessment of strength, motor function, quality of life, and adverse effect assessments. SOD1 levels were measured in erythrocytes and CSF. Pyrimethamine was measured in plasma and CSF. Appel ALS score, ALS Functional Rating Scale-Revised, and McGill Quality of Life Single-Item Scale were measured at screening, visit 6, and visit 9. We enrolled 32 patients; 24 completed 6 visits (18 weeks), and 21 completed all study visits. A linear mixed effects model showed a significant reduction in CSF SOD1 at visit 6 (p < 0.001) with a mean reduction of 13.5% (95% confidence interval [CI] = 8.4-18.5) and at visit 9 (p < 0.001) with a mean reduction of 10.5% (95% CI = 5.2-15.8). Pyrimethamine is safe and well tolerated in ALS. Pyrimethamine is capable of producing a significant reduction in total CSF SOD1 protein content in patients with ALS caused by different SOD1 mutations. Further long-term studies are warranted to assess clinical efficacy. Ann Neurol 2017;81:837-848. © 2017 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.

Altered Phenotypes in Saccharomyces cerevisiae by Heterologous Expression of Basidiomycete Moniliophthora perniciosa SOD2 Gene.

PubMed

Melo, Sônia C; Santos, Regineide X; Melgaço, Ana C; Pereira, Alanna C F; Pungartnik, Cristina; Brendel, Martin

2015-06-01

Heterologous expression of a putative manganese superoxide dismutase gene (SOD2) of the basidiomycete Moniliophthora perniciosa complemented the phenotypes of a Saccharomyces cerevisiae sod2Δ mutant. Sequence analysis of the cloned M. perniciosa cDNA revealed an open reading frame (ORF) coding for a 176 amino acid polypeptide with the typical metal-binding motifs of a SOD2 gene, named MpSOD2. Phylogenetic comparison with known manganese superoxide dismutases (MnSODs) located the protein of M. perniciosa (MpSod2p) in a clade with the basidiomycete fungi Coprinopsis cinerea and Laccaria bicolor. Haploid wild-type yeast transformants containing a single copy of MpSOD2 showed increased resistance phenotypes against oxidative stress-inducing hydrogen peroxide and paraquat, but had unaltered phenotype against ultraviolet-C (UVC) radiation. The same transformants exhibited high sensitivity against treatment with the pro-mutagen diethylnitrosamine (DEN) that requires oxidation to become an active mutagen/carcinogen. Absence of MpSOD2 in the yeast sod2Δ mutant led to DEN hyper-resistance while introduction of a single copy of this gene restored the yeast wild-type phenotype. The haploid yeast wild-type transformant containing two SOD2 gene copies, one from M. perniciosa and one from its own, exhibited DEN super-sensitivity. This transformant also showed enhanced growth at 37 °C on the non-fermentable carbon source lactate, indicating functional expression of MpSod2p. The pro-mutagen dihydroethidium (DHE)-based fluorescence assay monitored basal level of yeast cell oxidative stress. Compared to the wild type, the yeast sod2Δ mutant had a much higher level of intrinsic oxidative stress, which was reduced to wild type (WT) level by introduction of one copy of the MpSOD2 gene. Taken together our data indicates functional expression of MpSod2 protein in the yeast S. cerevisiae.

Altered Phenotypes in Saccharomyces cerevisiae by Heterologous Expression of Basidiomycete Moniliophthora perniciosa SOD2 Gene

PubMed Central

Melo, Sônia C.; Santos, Regineide X.; Melgaço, Ana C.; Pereira, Alanna C. F.; Pungartnik, Cristina; Brendel, Martin

2015-01-01

Heterologous expression of a putative manganese superoxide dismutase gene (SOD2) of the basidiomycete Moniliophthora perniciosa complemented the phenotypes of a Saccharomyces cerevisiae sod2Δ mutant. Sequence analysis of the cloned M. perniciosa cDNA revealed an open reading frame (ORF) coding for a 176 amino acid polypeptide with the typical metal-binding motifs of a SOD2 gene, named MpSOD2. Phylogenetic comparison with known manganese superoxide dismutases (MnSODs) located the protein of M. perniciosa (MpSod2p) in a clade with the basidiomycete fungi Coprinopsis cinerea and Laccaria bicolor. Haploid wild-type yeast transformants containing a single copy of MpSOD2 showed increased resistance phenotypes against oxidative stress-inducing hydrogen peroxide and paraquat, but had unaltered phenotype against ultraviolet–C (UVC) radiation. The same transformants exhibited high sensitivity against treatment with the pro-mutagen diethylnitrosamine (DEN) that requires oxidation to become an active mutagen/carcinogen. Absence of MpSOD2 in the yeast sod2Δ mutant led to DEN hyper-resistance while introduction of a single copy of this gene restored the yeast wild-type phenotype. The haploid yeast wild-type transformant containing two SOD2 gene copies, one from M. perniciosa and one from its own, exhibited DEN super-sensitivity. This transformant also showed enhanced growth at 37 °C on the non-fermentable carbon source lactate, indicating functional expression of MpSod2p. The pro-mutagen dihydroethidium (DHE)-based fluorescence assay monitored basal level of yeast cell oxidative stress. Compared to the wild type, the yeast sod2Δ mutant had a much higher level of intrinsic oxidative stress, which was reduced to wild type (WT) level by introduction of one copy of the MpSOD2 gene. Taken together our data indicates functional expression of MpSod2 protein in the yeast S. cerevisiae. PMID:26039235

The activity of superoxide dismutases (SODs) at the early stages of wheat deetiolation

PubMed Central

Zimak-Piekarczyk, Paulina; Ślesak, Ireneusz

2018-01-01

Unbound tetrapyrroles, i.e. protochlorophyllide (Pchlide), chlorophyllide and chlorophylls, bring the risk of reactive oxygen species (ROS) being generated in the initial stages of angiosperm deetiolation due to inefficient usage of the excitation energy for photosynthetic photochemistry. We analyzed the activity of superoxide dismutases (SODs) in etiolated wheat (Triticum aestivum) leaves and at the beginning of their deetiolation. Mn-SOD and three isoforms of Cu/Zn-SODs were identified both in etiolated and greening leaves of T. aestivum. Two Cu/Zn-SODs, denoted as II and III, were found in plastids. The activity of plastidic Cu/Zn-SOD isoforms as well as that of Mn-SOD correlated with cell aging along a monocot leaf, being the highest at leaf tips. Moreover, a high Pchlide content at leaf tips was observed. No correlation between SOD activity and the accumulation of photoactive Pchlide, i.e. Pchlide bound into ternary Pchlide:Pchlide oxidoreductase:NADPH complexes was found. Cu/Zn-SOD I showed the highest activity at the leaf base. A flash of light induced photoreduction of the photoactive Pchlide to chlorophyllide as well as an increase in all the SODs activity which occurred in a minute time-scale. In the case of seedlings that were deetiolated under continuous light of moderate intensity (100 μmol photons m-2 s-1), only some fluctuations in plastidic Cu/Zn-SODs and Mn-SOD within the first four hours of greening were noticed. The activity of SODs is discussed with respect to the assembly of tetrapyrroles within pigment-protein complexes, monitored by fluorescence spectroscopy at 77 K. PMID:29558520

Molecular and expression analysis of manganese superoxide dismutase (Mn-SOD) gene under temperature and starvation stress in rotifer Brachionus calyciflorus.

PubMed

Yang, Jianghua; Dong, Siming; Zhu, Huanxi; Jiang, Qichen; Yang, Jiaxin

2013-04-01

Superoxide dismutase (SOD) is an important antioxidant enzyme that protects organs from damage by reactive oxygen species. We cloned cDNA encoding SOD activated with manganese (Mn-SOD) from the rotifer Brachionus calyciflorus Pallas. The full-length cDNA of Mn-SOD was 1,016 bp and had a 669 bp open reading frame encoding 222 amino acids. The deduced amino acid sequence of B. calyciflorus Mn-SOD showed 89.1, 71.3, and 62.1 % similarity with the Mn-SOD of the marine rotifer Brachionus plicatilis, the nematode Caenorhabditis elegans, and the fruit fly Drosophila melanogaster, respectively. The phylogenetic tree constructed based on the amino acid sequences of Mn-SODs from B. calyciflorus and other organisms revealed that this rotifer is closely related to nematodes. Analysis of the mRNA expression of Mn-SOD under different conditions revealed that expression was enhanced 5.6-fold (p < 0.001) at 30 °C after 2 h, however, low temperature (15 °C) promoted Mn SOD temporarily (2.5-fold, p < 0.001) and then decreased to normal level (p > 0.05). Moderate starvation promoted Mn-SOD mRNA expression (p 12 < 0.01, p 36 < 0.05), which reached a maximum value (15.3 times higher than control, p 24 < 0.01) at 24 h. SOD and CAT activities also elevated at the 12 h-starved group. These results indicate that induction of Mn-SOD expression by stressors likely plays an important role in aging of B. calyciflorus.

The effect of amyotrophic lateral sclerosis-linked exogenous SOD1-G93A on electrophysiological properties and intracellular calcium in cultured rat astrocytes.

PubMed

Milošević, Milena; Bataveljić, Danijela; Nikolić, Ljiljana; Bijelić, Dunja; Andjus, Pavle

2016-01-01

Over 150 mutations in the SOD1 gene that encodes Cu/Zn superoxide dismutase (SOD1) cause 20-25% of familial ALS, albeit without a known gain-of-function mechanism. ALS is also non-cell-autonomous, the interactions between motor neurons and their glial neighbours being implicated in disease progression. The aim here was to investigate the biophysical effects of the exogenous human mutant SOD1-G93A on rat astrocytes in culture. Primary cortical astrocyte cultures were treated with recombinant human apo- mSOD1-G93A vs. wild-type control (wtSOD1) and recorded by patch-clamp and calcium imaging. Results showed that exogenous mSOD1 as well as wtSOD1 induced a decrease of membrane resistance, the effect being persistent (up to 13 min) only for the mutant form. Similarly, whole-cell inward currents in astrocytes were augmented by both wt and mSOD1, but the effect was twice larger and only progressed continuously for the latter. Both forms of SOD1 also induced a rise in intracellular Ca(2+) activity, the effect being dependent on external Ca(2+) and again only persisted with mSOD1, becoming significantly different from wtSOD1 only at longer times (14 min). In conclusion, this study points to membrane permeability and Ca(2+) signalling as processes affected by SOD1-G93A that presents the humoral factor triggering the role of astrocytes in ALS pathophysiology.

Epigenetic reprogramming governs EcSOD expression during human mammary epithelial cell differentiation, tumorigenesis and metastasis

PubMed Central

Teoh-Fitzgerald, ML; Fitzgerald, MP; Zhong, W; Askeland, RW; Domann, FE

2013-01-01

Expression of the antioxidant enzyme EcSOD in normal human mammary epithelial cells was not recognized until recently. Although expression of EcSOD was not detectable in non-malignant human mammary epithelial cells (HMEC) cultured in conventional two-dimensional (2D) culture conditions, EcSOD protein expression was observed in normal human breast tissues, suggesting that the 2D-cultured condition induces a repressive status of EcSOD gene expression in HMEC. With the use of laminin-enriched extracellular matrix (lrECM), we were able to detect expression of EcSOD when HMEC formed polarized acinar structures in a 3D-culture condition. Repression of the EcSOD-gene expression was again seen when the HMEC acini were sub-cultured as a monolayer, implying that lrECM-induced acinar morphogenesis is essential in EcSOD-gene activation. We have further shown the involvement of DNA methylation in regulating EcSOD expression in HMEC under these cell culture conditions. EcSOD mRNA expression was strongly induced in the 2D-cultured HMEC after treatment with a DNA methyltransferase inhibitor. In addition, epigenetic analyses showed a decrease in the degree of CpG methylation in the EcSOD promoter in the 3D versus 2D-cultured HMEC. More importantly, >80% of clinical mammary adenocarcinoma samples showed significantly decreased EcSOD mRNA and protein expression levels compared with normal mammary tissues and there is an inverse correlation between the expression levels of EcSOD and the clinical stages of breast cancer. Combined bisulfite restriction analysis analysis of some of the tumors also revealed an association of DNA methylation with the loss of EcSOD expression in vivo. Furthermore, overexpression of EcSOD inhibited breast cancer metastasis in both the experimental lung metastasis model and the syngeneic mouse model. This study suggests that epigenetic silencing of EcSOD may contribute to mammary tumorigenesis and that restoring the extracellular superoxide scavenging activity could be an effective strategy for breast cancer treatment. PMID:23318435

Increasing dissolved-oxygen disrupts iron homeostasis in production cultures of Escherichia coli.

PubMed

Baez, Antonino; Shiloach, Joseph

2017-01-01

The damaging effect of high oxygen concentration on growth of Escherichia coli is well established. Over-oxygenation increases the intracellular concentration of reactive oxygen species (ROS), causing the destruction of the [4Fe-4S] cluster of dehydratases and limiting the biosynthesis of both branched-chain amino acids and nicotinamide adenine dinucleotide. A key enzyme that reduces the damaging effect of superoxide is superoxide dismutase (SOD). Its transcriptional regulation is controlled by global transcription regulators that respond to changes in oxygen and iron concentrations and pH. Production of biological compounds from E. coli is currently achieved using cultures grown to high cell densities which require oxygen-enriched air supply. It is, therefore, important to study the effect of over-oxygenation on E. coli metabolism and the bacterial protecting mechanism. The effect of over-oxygenation on the superoxide dismutase regulation system was evaluated in cultures grown in a bioreactor by increasing the oxygen concentration from 30 to 300 % air saturation. Following the change in the dissolved oxygen (DO), the expression of sodC, the periplasmic CuZn-containing SOD, and sodA, the cytosolic Mn-containing SOD, was higher in all the tested strains, while the expression of the sodB, the cytosolic Fe-containing SOD, was lower. The down-regulation of the sodB was found to be related to the activation of the small RNA RyhB. It was revealed that iron homeostasis, in particular ferric iron, was involved in the RyhB activation and in sodB regulation but not in sodA. Supplementation of amino acids to the culture medium reduced the intracellular ROS accumulation and reduced the activation of both SodA and SodC following the increase in the oxygen concentration. The study provides evidence that at conditions of over-oxygenation, sodA and sodC are strongly regulated by the amount of ROS, in particular superoxide; and sodB is regulated by iron availability through the small RNA RyhB. In addition, information on the impact of NADH, presence of amino acids and type of iron on SOD regulation, and consequently, on the ROS concentration is provided.

Insight into the structure and mechanism of nickel-containing superoxide dismutase derived from peptide-based mimics.

PubMed

Shearer, Jason

2014-08-19

Nickel superoxide dismutase (NiSOD) is a nickel-containing metalloenzyme that catalyzes the disproportionation of superoxide through a ping-pong mechanism that relies on accessing reduced Ni(II) and oxidized Ni(III) oxidation states. NiSOD is the most recently discovered SOD. Unlike the other known SODs (MnSOD, FeSOD, and (CuZn)SOD), which utilize "typical" biological nitrogen and oxygen donors, NiSOD utilizes a rather unexpected ligand set. In the reduced Ni(II) oxidation state, NiSOD utilizes nitrogen ligands derived from the N-terminal amine and an amidate along with two cysteinates sulfur donors. These are unusual biological ligands, especially for an SOD: amine and amidate donors are underrepresented as biological ligands, whereas cysteinates are highly susceptible to oxidative damage. An axial histidine imidazole binds to nickel upon oxidation to Ni(III). This bond is long (2.3-2.6 Å) owing to a tight hydrogen-bonding network. All of the ligating residues to Ni(II) and Ni(III) are found within the first 6 residues from the NiSOD N-terminus. Thus, small nickel-containing metallopeptides derived from the first 6-12 residues of the NiSOD sequence can reproduce many of the properties of NiSOD itself. Using these nickel-containing metallopeptide-based NiSOD mimics, we have shown that the minimal sequence needed for nickel binding and reproduction of the structural, spectroscopic, and functional properties of NiSOD is H2N-HCXXPC. Insight into how NiSOD avoids oxidative damage has also been gained. Using small NiN2S2 complexes and metallopeptide-based mimics, it was shown that the unusual nitrogen donor atoms protect the cysteinates from oxidative damage (both one-electron oxidation and oxygen atom insertion reactions) by fine-tuning the electronic structure of the nickel center. Changing the nitrogen donor set to a bis-amidate or bis-amine nitrogen donor led to catalytically nonviable species owing to nickel-cysteinate bond oxidative damage. Only the amine/amidate nitrogen donor atoms within the NiSOD ligand set produce a catalytically viable species. These metallopeptide-based mimics have also hinted at the detailed mechanism of SOD catalysis by NiSOD. One such aspect is that the axial imidazole likely remains ligated to the Ni center under rapid catalytic conditions (i.e., high superoxide loads). This reduces the degree of structural rearrangement about the nickel center, leading to higher catalytic rates. Metallopeptide-based mimics have also shown that, although an axial ligand to Ni(III) is required for catalysis, the rates are highest when this is a weak interaction, suggesting a reason for the long axial His-Ni(III) bond found in NiSOD. These mimics have also suggested a surprising mechanistic insight: O2(-) reduction via a "H(•)" tunneling event from a R-S(H(+))-Ni(II) moiety to O2(-) is possible. The importance of this mechanism in NiSOD has not been verified.

Copper-Zinc Superoxide Dismutase: A Unique Biological "Ligand" for Bioinorganic Studies.

ERIC Educational Resources Information Center

Valentine, Joan Selverstone; de Freitas, Duarte Mota

1985-01-01

Discusses superoxide dismutase (SOD) research and the properties of copper, zinc (Cu, Zn)-SOD. Emphasizes the controversy concerning the role of Cu,Zn-SOD and other SOD enzymes as protective agents in reactions involving dioxygen metabolism, and the properties of Cu, Zn-SOD that make it an interesting biological ligand for physical studies of…

Early superoxide dismutase alterations during SV40-transformation of human fibroblasts.

PubMed

Bravard, A; Hoffschir, F; Sabatier, L; Ricoul, M; Pinton, A; Cassingena, R; Estrade, S; Luccioni, C; Dutrillaux, B

1992-11-11

The expression of superoxide dismutases (SOD) 1 and 2 was studied in 4 clones of human fibroblasts after their infection by simian virus 40 (SV40), in parallel with the alterations of chromosomes 21 and chromosome 6q arms, carrying the genes that encode for SOD1 and SOD2 respectively. For all clones, a similar scheme with 2 main phases was observed for both chromosome and SOD variations. The first phase, defined as the pre-crisis phase, was characterized by chromosomal instability, but maintenance of normal numbers of chromosome 6q arms and chromosomes 21. The level of SOD2 mRNA was high, while SOD2 activity and immunoreactive protein were low. SOD1 protein and activity were decreased. In the second phase, defined as the post-crisis phase, the accumulation of clonal chromosomal rearrangements led to the loss of 6q arms, while the number of chromosomes 21 remained normal. SOD2 mRNA level was decreased and SOD2 immunoreactive protein and activity remained low. SOD1 protein and activity increased with passages, reaching values similar to those of control cells at late passages. As in established SV40-transformed human fibroblast cell lines, good correlation was found between SOD2 activity and the relative number of 6q arms. These results allow us to reconstruct the sequence of events leading to the decrease of SOD2, a possible tumor-suppressor gene, during the process of SV40-transformation of human fibroblasts.

Immunolocalization of antioxidant enzymes in high-pressure frozen root and stem nodules of Sesbania rostrata.

PubMed

Rubio, Maria C; Becana, Manuel; Kanematsu, Sumio; Ushimaru, Takashi; James, Euan K

2009-01-01

The activities and localizations of superoxide dismutases (SODs) were compared in root and stem nodules of the semi-aquatic legume Sesbania rostrata using gel-activity assays and immunogold labelling, respectively. Nodules were fixed by high-pressure freezing and dehydrated by freeze substitution. Stem nodules showed more total and specific SOD activities than root nodules because of the presence of chloroplastic CuZnSOD. Most of the total SOD activity of stem and root nodules resulted from 'cytosolic' CuZnSOD, localized in the cytoplasm and chromatin, and from MnSOD in the bacteroids and in the mitochondria of vascular tissue. FeSOD was present in nodule plastids and in leaf chloroplasts, and was found to be associated with chromatin. Superoxide production was detected histochemically in the vascular bundles and in the infected tissue of stem and root nodules, whereas peroxide accumulation was observed in the cortical cell walls and intercellular spaces, as well as within the infection threads of both nodule types. These data suggest a role of CuZnSOD and FeSOD in protecting nuclear DNA from reactive oxygen species and/or in modulating gene activity. The enhanced levels of CuZnSOD, MnSOD and superoxide production in vascular bundle cells are consistent with a role of CuZnSOD and superoxide in the lignification of xylem vessels, but also suggest additional functions in coping with superoxide production by the high respiratory activity of parenchyma cells.

Determining the Effect of Catechins on SOD1 Conformation and Aggregation by Ion Mobility Mass Spectrometry Combined with Optical Spectroscopy

NASA Astrophysics Data System (ADS)

Zhao, Bing; Zhuang, Xiaoyu; Pi, Zifeng; Liu, Shu; Liu, Zhiqiang; Song, Fengrui

2018-02-01

The aggregation of Cu,Zn-superoxide dismutase (SOD1) plays an important role in the etiology of amyotrophic lateral sclerosis (ALS). For the disruption of ALS progression, discovering new drugs or compounds that can prevent SOD1 aggregation is important. In this study, ESI-MS was used to investigate the interaction of catechins and SOD1. The noncovalent complex of catechins that interact with SOD1 was found and retained in the gas phase under native ESI-MS condition. The conformation changes of SOD1 after binding with catechins were also explored via traveling wave ion mobility (IM) spectrometry. Epigallocatechin gallate (EGCG) can stabilize SOD1 conformation against unfolding in three catechins. To further evaluate the efficacy of EGCG, we monitored the fluorescence changes of dimer E2,E2,-SOD1(apo-SOD1, E:empty) with and without ligands under denaturation conditions, and found that EGCG can inhibit apo-SOD1 aggregation. In addition, the circular dichroism spectra of the samples showed that EGCG can decrease the β-sheet content of SOD1, which can produce aggregates. These results indicated that orthogonal separation dimension in the gas-phase IM coupled with ESI-MS (ESI-IM-MS) can potentially provide insight into the interaction between SOD1 and small molecules. The advantage is that it dramatically decreases the analysis time. Meantime, optical spectroscopy techniques can be used to confirm ESI-IM-MS results. [Figure not available: see fulltext.

Size and targeting to PECAM vs ICAM control endothelial delivery, internalization and protective effect of multimolecular SOD conjugates.

PubMed

Shuvaev, Vladimir V; Muro, Silvia; Arguiri, Evguenia; Khoshnejad, Makan; Tliba, Samira; Christofidou-Solomidou, Melpo; Muzykantov, Vladimir R

2016-07-28

Controlled endothelial delivery of SOD may alleviate abnormal local surplus of superoxide involved in ischemia-reperfusion, inflammation and other disease conditions. Targeting SOD to endothelial surface vs. intracellular compartments is desirable to prevent pathological effects of external vs. endogenous superoxide, respectively. Thus, SOD conjugated with antibodies to cell adhesion molecule PECAM (Ab/SOD) inhibits pro-inflammatory signaling mediated by endogenous superoxide produced in the endothelial endosomes in response to cytokines. Here we defined control of surface vs. endosomal delivery and effect of Ab/SOD, focusing on conjugate size and targeting to PECAM vs. ICAM. Ab/SOD enlargement from about 100 to 300nm enhanced amount of cell-bound SOD and protection against extracellular superoxide. In contrast, enlargement inhibited endocytosis of Ab/SOD and diminished mitigation of inflammatory signaling of endothelial superoxide. In addition to size, shape is important: endocytosis of antibody-coated spheres was more effective than that of polymorphous antibody conjugates. Further, targeting to ICAM provides higher endocytic efficacy than targeting to PECAM. ICAM-targeted Ab/SOD more effectively mitigated inflammatory signaling by intracellular superoxide in vitro and in animal models, although total uptake was inferior to that of PECAM-targeted Ab/SOD. Therefore, both geometry and targeting features of Ab/SOD conjugates control delivery to cell surface vs. endosomes for optimal protection against extracellular vs. endosomal oxidative stress, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Extracellular Superoxide Dismutase Inhibits Innate Immune Responses and Clearance of an Intracellular Bacterial Infection

PubMed Central

Break, Timothy J.; Jun, Sujung; Indramohan, Mohanalaxmi; Carr, Karen D.; Sieve, Amy N.; Dory, Ladislav; Berg, Rance E.

2012-01-01

Reactive oxygen and nitrogen species (ROS/RNS) play important roles during immune responses to bacterial pathogens. Extracellular superoxide dismutase (ecSOD) regulates extracellular concentrations of ROS/RNS and contributes to tissue protection during inflammatory insults. The participation of ecSOD in immune responses seems therefore intuitive, yet is poorly understood. In the present study, we utilized mice with varying levels of ecSOD activity to investigate the involvement of this enzyme in immune responses against Listeria monocytogenes. Surprisingly, our data demonstrate that, despite enhanced neutrophil recruitment to the liver, ecSOD activity negatively impacted host survival and bacterial clearance. Increased ecSOD activity was accompanied by decreased co-localization of neutrophils with bacteria, as well as increased neutrophil apoptosis, which reduced overall and neutrophil-specific TNF-α production. Liver leukocytes from mice lacking ecSOD produced equivalent nitric oxide (NO·) when compared to mice expressing ecSOD. However, during infection, there were higher levels of peroxynitrite (NO3·−) in livers from mice lacking ecSOD compared to mice expressing ecSOD. Neutrophil depletion studies revealed that high levels of ecSOD activity resulted in neutrophils with limited protective capacity, whereas neutrophils from mice lacking ecSOD provided superior protection compared to neutrophils from wild-type mice. Taken together, our data demonstrate that ecSOD activity reduces innate immune responses during bacterial infection and provides a potential target for therapeutic intervention. PMID:22393157

Cholic acid modified N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride for superoxide dismutase delivery.

PubMed

Cheng, Ye; Cai, Huanxin; Yin, Baoru; Yao, Ping

2013-09-15

A series of novel amphiphilic chitosan derivatives, cholic acid modified N-(2-hydroxy)-propyl-3-trimethylammonium chitosan chloride (HTCC-CA) with different quaternization degrees and cholic acid substitutions were synthesized in this study. HTCC-CA is biocompatible and forms particles in aqueous solution. The binding with superoxide dismutase (SOD) at pH 6.8 destroys the original aggregates of HTCC-CA and produces smaller SOD/HTCC-CA complex nanoparticles via electrostatic and hydrophobic interactions. The SOD loading efficiency and loading capacity of HTCC-CA can reach to more than 90% and 45%, respectively. Confocal laser scanning microscopy observation and flow cytometry analysis reveal that SOD/HTCC-CA complex nanoparticles greatly enhance the cellular internalization of the loaded SOD. The SOD activities and malonaldehyde concentrations in the serum and organs of the rats, administrated intravenously with free SOD, free HTCC-CA, and SOD/HTCC-CA nanoparticles, were assayed to evaluate the antioxidant efficiency in vivo. The results demonstrate that free HTCC-CA is effective to scavenge superoxide radicals in the blood circulation and SOD/HTCC-CA nanoparticles have better antioxidant efficiency than free SOD as well as free HTCC-CA. Copyright © 2013 Elsevier B.V. All rights reserved.

Parkin Protects Against Misfolded SOD1 Toxicity by Promoting Its Aggresome Formation and Autophagic Clearance.

PubMed

Yung, Cheryl; Sha, Di; Li, Lian; Chin, Lih-Shen

2016-11-01

Mutations in Cu/Zn superoxide dismutase (SOD1) cause autosomal dominant amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disease with no effective treatment. Despite ample evidence indicating involvement of mutation-induced SOD1 protein misfolding and aggregation in ALS pathogenesis, the molecular mechanisms that control cellular management of misfolded, aggregation-prone SOD1 mutant proteins remain unclear. Here, we report that parkin, an E3 ubiquitin-protein ligase which is linked to Parkinson's disease, is a novel regulator of cellular defense against toxicity induced by ALS-associated SOD1 mutant proteins. We find that parkin mediates K63-linked polyubiquitination of SOD1 mutants in cooperation with the UbcH13/Uev1a E2 enzyme and promotes degradation of these misfolded SOD1 proteins by the autophagy-lysosome system. In response to strong proteotoxic stress associated with proteasome impairment, parkin promotes sequestration of misfolded and aggregated SOD1 proteins to form perinuclear aggresomes, regulates positioning of lysosomes around misfolded SOD1 aggresomes, and facilitates aggresome clearance by autophagy. Our findings reveal parkin-mediated cytoprotective mechanisms against misfolded SOD1 toxicity and suggest that enhancing parkin-mediated cytoprotection may provide a novel therapeutic strategy for treating ALS.

Activation of CuZn superoxide dismutases from Caenorhabditis elegans does not require the copper chaperone CCS.

PubMed

Jensen, Laran T; Culotta, Valeria Cizewski

2005-12-16

Reactive oxygen species are produced as the direct result of aerobic metabolism and can cause damage to DNA, proteins, and lipids. A principal defense against reactive oxygen species involves the superoxide dismutases (SOD) that act to detoxify superoxide anions. Activation of CuZn-SODs in eukaryotic cells occurs post-translationally and is generally dependent on the copper chaperone for SOD1 (CCS), which inserts the catalytic copper cofactor and catalyzes the oxidation of a conserved disulfide bond that is essential for activity. In contrast to other eukaryotes, the nematode Caenorhabditis elegans does not contain an obvious CCS homologue, and we have found that the C. elegans intracellular CuZn-SODs (wSOD-1 and wSOD-5) are not dependent on CCS for activation when expressed in Saccharomyces cerevisiae. CCS-independent activation of CuZn-SODs is not unique to C. elegans; however, this is the first organism identified that appears to exclusively use this alternative pathway. As was found for mammalian SOD1, wSOD-1 exhibits a requirement for reduced glutathione in CCS-independent activation. Unexpectedly, wSOD-1 was inactive even in the presence of CCS when glutathione was depleted. Our investigation of the cysteine residues that form the disulfide bond in wSOD-1 suggests that the ability of wSODs to readily form this disulfide bond may be the key to obtaining high levels of activation through the CCS-independent pathway. Overall, these studies demonstrate that the CuZn-SODs of C. elegans have uniquely evolved to acquire copper without the copper chaperone and this may reflect the lifestyle of this organism.

Manganese Superoxide Dismutase Is a Promising Target for Enhancing Chemosensitivity of Basal-Like Breast Carcinoma

PubMed Central

Kumar, Alan Prem; Loo, Ser Yue; Shin, Sung Won; Tan, Tuan Zea; Eng, Chon Boon; Singh, Rajeev; Putti, Thomas Choudary; Ong, Chee Wee; Salto-Tellez, Manuel; Goh, Boon Cher; Park, Joo In; Thiery, Jean Paul; Pervaiz, Shazib

2014-01-01

Abstract Aims: Although earlier reports highlighted a tumor suppressor role for manganese superoxide dismutase (MnSOD), recent evidence indicates increased expression in a variety of human cancers including aggressive breast carcinoma. In the present article, we hypothesized that MnSOD expression is significantly amplified in the aggressive breast carcinoma basal subtype, and targeting MnSOD could be an attractive strategy for enhancing chemosensitivity of this highly aggressive breast cancer subtype. Results: Using MDA-MB-231 and BT549 as a model of basal breast cancer cell lines, we show that knockdown of MnSOD decreased the colony-forming ability and sensitized the cells to drug-induced cell death, while drug resistance was associated with increased MnSOD expression. In an attempt to develop a clinically relevant approach to down-regulate MnSOD expression in patients with basal breast carcinoma, we employed activation of the peroxisome proliferator-activated receptor gamma (PPARγ) to repress MnSOD expression; PPARγ activation significantly reduced MnSOD expression, increased chemosensitivity, and inhibited tumor growth. Moreover, as a proof of concept for the clinical use of PPARγ agonists to decrease MnSOD expression, biopsies derived from breast cancer patients who had received synthetic PPARγ ligands as anti-diabetic therapy had significantly reduced MnSOD expression. Finally, we provide evidence to implicate peroxynitrite as the mechanism involved in the increased sensitivity to chemotherapy induced by MnSOD repression. Innovation and Conclusion: These data provide evidence to link increased MnSOD expression with the aggressive basal breast cancer, and underscore the judicious use of PPARγ ligands for specifically down-regulating MnSOD to increase the chemosensitivity of this subtype of breast carcinoma. Antioxid. Redox Signal. 20, 2326–2346. PMID:23964924

Basal brain oxidative and nitrative stress levels are finely regulated by the interplay between superoxide dismutase 2 and p53.

PubMed

Barone, Eugenio; Cenini, Giovanna; Di Domenico, Fabio; Noel, Teresa; Wang, Chi; Perluigi, Marzia; St Clair, Daret K; Butterfield, D Allan

2015-11-01

Superoxide dismutases (SODs) are the primary reactive oxygen species (ROS)-scavenging enzymes of the cell and catalyze the dismutation of superoxide radicals O2- to H2O2 and molecular oxygen (O2). Among the three forms of SOD identified, manganese-containing SOD (MnSOD, SOD2) is a homotetramer located wholly in the mitochondrial matrix. Because of the SOD2 strategic location, it represents the first mechanism of defense against the augmentation of ROS/reactive nitrogen species levels in the mitochondria for preventing further damage. This study seeks to understand the effects that the partial lack (SOD2(-/+) ) or the overexpression (TgSOD2) of MnSOD produces on oxidative/nitrative stress basal levels in different brain isolated cellular fractions (i.e., mitochondrial, nuclear, cytosolic) as well as in the whole-brain homogenate. Furthermore, because of the known interaction between SOD2 and p53 protein, this study seeks to clarify the impact that the double mutation has on oxidative/nitrative stress levels in the brain of mice carrying the double mutation (p53(-/-) × SOD2(-/+) and p53(-/-) × TgSOD2). We show that each mutation affects mitochondrial, nuclear, and cytosolic oxidative/nitrative stress basal levels differently, but, overall, no change or reduction of oxidative/nitrative stress levels was found in the whole-brain homogenate. The analysis of well-known antioxidant systems such as thioredoxin-1 and Nrf2/HO-1/BVR-A suggests their potential role in the maintenance of the cellular redox homeostasis in the presence of changes of SOD2 and/or p53 protein levels. © 2015 Wiley Periodicals, Inc.

Involvement of Superoxide Dismutase in Spore Coat Assembly in Bacillus subtilis

PubMed Central

Henriques, Adriano O.; Melsen, Lawrence R.; Moran, Charles P.

1998-01-01

Endospores of Bacillus subtilis are enclosed in a proteinaceous coat which can be differentiated into a thick, striated outer layer and a thinner, lamellar inner layer. We found that the N-terminal sequence of a 25-kDa protein present in a preparation of spore coat proteins matched that of the Mn-dependent superoxide dismutase (SOD) encoded by the sodA locus. sodA is transcribed throughout the growth and sporulation of a wild-type strain and is responsible for the SOD activity detected in total cell extracts prepared from B. subtilis. Disruption of the sodA locus produced a mutant that lacked any detectable SOD activity during vegetative growth and sporulation. The sodA mutant was not impaired in the ability to form heat- or lysozyme-resistant spores. However, examination of the coat layers of sodA mutant spores revealed increased extractability of the tyrosine-rich outer coat protein CotG. We showed that this condition was not accompanied by augmented transcription of the cotG gene in sporulating cells of the sodA mutant. We conclude that SodA is required for the assembly of CotG into the insoluble matrix of the spore and suggest that CotG is covalently cross-linked into the insoluble matrix by an oxidative reaction dependent on SodA. Ultrastructural analysis revealed that the inner coat formed by a sodA mutant was incomplete. Moreover, the outer coat lacked the characteristic striated appearance of wild-type spores, a pattern that was accentuated in a cotG mutant. These observations suggest that the SodA-dependent formation of the insoluble matrix containing CotG is largely responsible for the striated appearance of this coat layer. PMID:9573176

Molecular cloning and characterization of Siamese crocodile (Crocodylus siamensis) copper, zinc superoxide dismutase (CSI-Cu,Zn-SOD) gene.

PubMed

Sujiwattanarat, Penporn; Pongsanarakul, Parinya; Temsiripong, Yosapong; Temsiripong, Theeranan; Thawornkuno, Charin; Uno, Yoshinobu; Unajak, Sasimanas; Matsuda, Yoichi; Choowongkomon, Kiattawee; Srikulnath, Kornsorn

2016-01-01

Superoxide dismutase (SOD, EC 1.15.1.1) is an antioxidant enzyme found in all living cells. It regulates oxidative stress by breaking down superoxide radicals to oxygen and hydrogen peroxide. A gene coding for Cu,Zn-SOD was cloned and characterized from Siamese crocodile (Crocodylus siamensis; CSI). The full-length expressed sequence tag (EST) of this Cu,Zn-SOD gene (designated as CSI-Cu,Zn-SOD) contained 462bp encoding a protein of 154 amino acids without signal peptides, indicated as intracellular CSI-Cu,Zn-SOD. This agreed with the results from the phylogenetic tree, which indicated that CSI-Cu,Zn-SOD belonged to the intracellular Cu,Zn-SOD. Chromosomal location determined that the CSI-Cu,Zn-SOD was localized to the proximal region of the Siamese crocodile chromosome 1p. Several highly conserved motifs, two conserved signature sequences (GFHVHEFGDNT and GNAGGRLACGVI), and conserved amino acid residues for binding copper and zinc (His(47), His(49), His(64), His(72), His(81), Asp(84), and His(120)) were also identified in CSI-Cu,Zn-SOD. Real-time PCR analysis showed that CSI-Cu,Zn-SOD mRNA was expressed in all the tissues examined (liver, pancreas, lung, kidney, heart, and whole blood), which suggests a constitutively expressed gene in these tissues. Expression of the gene in Escherichia coli cells followed by purification yielded a recombinant CSI-Cu,Zn-SOD, with Km and Vmax values of 6.075mM xanthine and 1.4×10(-3)mmolmin(-1)mg(-1), respectively. This Vmax value was 40 times lower than native Cu,Zn-SOD (56×10(-3)mmolmin(-1)mg(-1)), extracted from crocodile erythrocytes. This suggests that cofactors, protein folding properties, or post-translational modifications were lost during the protein purification process, leading to a reduction in the rate of enzyme activity in bacterial expression of CSI-Cu,Zn-SOD. Copyright © 2015 Elsevier Inc. All rights reserved.

Isolation, Chromosomal Localization, and Differential Expression of Mitochondrial Manganese Superoxide Dismutase and Chloroplastic Copper/Zinc Superoxide Dismutase Genes in Wheat1

PubMed Central

Wu, Guohai; Wilen, Ronald W.; Robertson, Albert J.; Gusta, Lawrence V.

1999-01-01

Superoxide dismutase (SOD) gene expression was investigated to elucidate its role in drought and freezing tolerance in spring and winter wheat (Triticum aestivum). cDNAs encoding chloroplastic Cu/ZnSODs and mitochondrial MnSODs were isolated from wheat. MnSOD and Cu/ZnSOD genes were mapped to the long arms of the homologous group-2 and -7 chromosomes, respectively. Northern blots indicated that MnSOD genes were drought inducible and decreased after rehydration. In contrast, Cu/ZnSOD mRNA was not drought inducible but increased after rehydration. In both spring and winter wheat seedlings exposed to 2°C, MnSOD transcripts attained maximum levels between 7 and 49 d. Transcripts of Cu/ZnSOD mRNA were detected sooner in winter than in spring wheat; however, they disappeared after 21 d of acclimation. Transcripts of both classes of SOD genes increased during natural acclimation in both spring and winter types. Exposure of fully hardened plants to three nonlethal freeze-thaw cycles resulted in Cu/Zn mRNA accumulation; however, MnSOD mRNA levels declined in spring wheat but remained unchanged in winter wheat. The results of the dehydration and freeze-thaw-cycle experiments suggest that winter wheat has evolved a more effective stress-repair mechanism than spring wheat. PMID:10364402

Molecular Cloning and Biochemical Characterization of the Iron Superoxide Dismutase from the Cyanobacterium Nostoc punctiforme ATCC 29133 and Its Response to Methyl Viologen-Induced Oxidative Stress.

PubMed

Moirangthem, Lakshmipyari Devi; Ibrahim, Kalibulla Syed; Vanlalsangi, Rebecca; Stensjö, Karin; Lindblad, Peter; Bhattacharya, Jyotirmoy

2015-12-01

Superoxide dismutase (SOD) detoxifies cell-toxic superoxide radicals and constitutes an important component of antioxidant machinery in aerobic organisms, including cyanobacteria. The iron-containing SOD (SodB) is one of the most abundant soluble proteins in the cytosol of the nitrogen-fixing cyanobacterium Nostoc punctiforme ATCC 29133, and therefore, we investigated its biochemical properties and response to oxidative stress. The putative SodB-encoding open reading frame Npun_R6491 was cloned and overexpressed in Escherichia coli as a C-terminally hexahistidine-tagged protein. The purified recombinant protein had a SodB specific activity of 2560 ± 48 U/mg protein at pH 7.8 and was highly thermostable. The presence of a characteristic iron absorption peak at 350 nm, and its sensitivity to H2O2 and azide, confirmed that the SodB is an iron-containing SOD. Transcript level of SodB in nitrogen-fixing cultures of N. punctiforme decreased considerably (threefold) after exposure to an oxidative stress-generating herbicide methyl viologen for 4 h. Furthermore, in-gel SOD activity analysis of such cultures grown at increasing concentrations of methyl viologen also showed a loss of SodB activity. These results suggest that SodB is not the primary scavenger of superoxide radicals induced by methyl viologen in N. punctiforme.

Characterization of Chemically Induced Liver Injuries Using Gene Co-Expression Modules

DTIC Science & Technology

2014-09-16

liver Sod2 Fibrosis/cirrhosis Sod2, Hao2, Sult1e1, Got1, Gulo, Obp3, Bdh1 Necrosis Sod2 Liver neoplasms Sod2, Rgn, Anxa2, Car3, Gstp1 Carcinoma Sod2... Gstp1 doi:10.1371/journal.pone.0107230.t006 Figure 10. Validation of external datasets. Scatter plots show the correlation of the log-ratios between

Cu/Zn superoxide dismutase and the proton ATPase Pma1p of Saccharomyces cerevisiae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baron, J. Allen; Chen, Janice S.; Culotta, Valeria C., E-mail: vculott1@jhu.edu

2015-07-03

In eukaryotes, the Cu/Zn containing superoxide dismutase (SOD1) plays a critical role in oxidative stress protection as well as in signaling. We recently demonstrated a function for Saccharomyces cerevisiae Sod1p in signaling through CK1γ casein kinases and identified the essential proton ATPase Pma1p as one likely target. The connection between Sod1p and Pma1p was explored further by testing the impact of sod1Δ mutations on cells expressing mutant alleles of Pma1p that alter activity and/or post-translational regulation of this ATPase. We report here that sod1Δ mutations are lethal when combined with the T912D allele of Pma1p in the C-terminal regulatory domain.more » This “synthetic lethality” was reversed by intragenic suppressor mutations in Pma1p, including an A906G substitution that lies within the C-terminal regulatory domain and hyper-activates Pma1p. Surprisingly the effect of sod1Δ mutations on Pma1-T912D is not mediated through the Sod1p signaling pathway involving the CK1γ casein kinases. Rather, Sod1p sustains life of cells expressing Pma1-T912D through oxidative stress protection. The synthetic lethality of sod1Δ Pma1-T912D cells is suppressed by growing cells under low oxygen conditions or by treatments with manganese-based antioxidants. We now propose a model in which Sod1p maximizes Pma1p activity in two ways: one involving signaling through CK1γ casein kinases and an independent role for Sod1p in oxidative stress protection. - Highlights: • In yeast, the anti-oxidant enzyme SOD1 promotes activity of the proton ATPase Pma1p. • Cells expressing a T912D variant of Pma1p are not viable without SOD1. • SOD1 is needed to protect Pma1-T912D expressing cells from severe oxidative damage. • SOD1 activates Pma1p through casein kinase signaling and oxidative stress protection.« less

Responses of transgenic Arabidopsis plants and recombinant yeast cells expressing a novel durum wheat manganese superoxide dismutase TdMnSOD to various abiotic stresses.

PubMed

Kaouthar, Feki; Ameny, Farhat-Khemakhem; Yosra, Kamoun; Walid, Saibi; Ali, Gargouri; Faiçal, Brini

2016-07-01

In plant cells, the manganese superoxide dismutase (Mn-SOD) plays an elusive role in the response to oxidative stress. In this study, we describe the isolation and functional characterization of a novel Mn-SOD from durum wheat (Triticum turgidum L. subsp. Durum), named TdMnSOD. Molecular phylogeny analysis showed that the durum TdMnSOD exhibited high amino acids sequence identity with other Mn-SOD plants. The three-dimensional structure showed that TdMnSOD forms a homotetramer and each subunit is composed of a predominantly α-helical N-terminal domain and a mixed α/β C-terminal domain. TdMnSOD gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdMnSOD enhances tolerance of the transformed yeast cells to salt, osmotic, cold and H2O2-induced oxidative stresses. Moreover, the analysis of TdMnSOD transgenic Arabidopsis plants subjected to different environmental stresses revealed low H2O2 and high proline levels as compared to the wild-type plants. Compared with the non-transformed plants, an increase in the total SOD and two other antioxidant enzyme activities including catalase (CAT) and peroxidases (POD) was observed in the three transgenic lines subjected to abiotic stress. Taken together, these data provide evidence for the involvement of durum wheat TdMnSOD in tolerance to multiple abiotic stresses in crop plants. Copyright © 2016 Elsevier GmbH. All rights reserved.

Peroxisomal membrane manganese superoxide dismutase: characterization of the isozyme from watermelon (Citrullus lanatus Schrad.) cotyledons.

PubMed

Rodríguez-Serrano, María; Romero-Puertas, María C; Pastori, Gabriela M; Corpas, Francisco J; Sandalio, Luisa M; del Río, Luis A; Palma, José M

2007-01-01

In this work the manganese superoxide dismutase (Mn-SOD) bound to peroxisomal membranes of watermelon cotyledons (Citrullus lanatus Schrad.) was purified to homogeneity and some of its molecular properties were determined. The stepwise purification procedure consisted of ammonium sulphate fractionation, batch anion-exchange chromatography, and anion-exchange and gel-filtration column chromatography using a fast protein liquid chromatography system. Peroxisomal membrane Mn-SOD (perMn-SOD; EC 1.15.1.1) was purified 5600-fold with a yield of 2.6 mug of enzyme g(-1) of cotyledons, and had a specific activity of 480 U mg(-1) of protein. The native molecular mass determined for perMn-SOD was 108 000 Da, and it was composed of four equal subunits of 27 kDa, which indicates that perMn-SOD is a homotetramer. Ultraviolet and visible absorption spectra of the enzyme showed a shoulder at 275 nm and two absorption maxima at 448 nm and 555 nm, respectively. By isoelectric focusing, a pI of 5.75 was determined for perMn-SOD. In immunoblot assays, purified perMn-SOD was recognized by a polyclonal antibody against Mn-SOD from pea leaves, and the peroxisomal enzyme rapidly dissociated in the presence of dithiothreitol and SDS. The potential binding of the Mn-SOD isozyme to the peroxisomal membrane was confirmed by immunoelectron microscopy analysis. The properties of perMn-SOD and the mitMn-SOD are compared and the possible function in peroxisomal membranes of the peripheral protein Mn-SOD is discussed.

Identification of the copper-zinc superoxide dismutase activity in Mycoplasma hyopneumoniae.

PubMed

Chen, J R; Weng, C N; Ho, T Y; Cheng, I C; Lai, S S

2000-05-11

Copper-zinc superoxide dismutase (Cu/ZnSOD), a key enzyme in defense against toxic oxygen-free radicals, is widespread in eukaryotes and several species of gram-negative bacteria. The presence of this enzyme in Mycoplasma hyopneumoniae (M. hyopneumoniae), the primary pathogen of mycoplasmal pneumonia in pigs, was examined since the polyclonal antibody against bovine Cu/ZnSOD was dominantly cross-reactive with the M. hyopneumoniae Cu/ZnSOD from whole cellular proteins. In situ activity staining on SDS-PAGE showed that the molecular mass of M. hyopneumoniae Cu/ZnSOD in reducing form was approximately 17kDa. The presence of Cu and Zn ions at the active site of the enzyme was confirmed on the basis of inhibition by KCN and by H(2)O(2). The activity of M. hyopneumoniae Cu/ZnSOD on both SDS- and native-polyacrylamide gels was completely inhibited by 2mM KCN and the gels showed no iron-containing SOD (FeSOD) or manganese-containing SOD (MnSOD) in the crude extracts. The activity of M. hyopneumoniae Cu/ZnSOD in crude extract was 70units/mg protein and was 55% inhibited by 5mM KCN and 56% inactivated by 40mM H(2)O(2). This enzyme was growth-stage dependent and evidenced markedly higher production during the early log phase. Different expression levels of Cu/ZnSOD activity in field isolates were also detected. Taken together, the presence of Cu/ZnSOD in M. hyopneumoniae was identified for the first time.

Identification of a misfolded region in superoxide dismutase 1 that is exposed in amyotrophic lateral sclerosis.

PubMed

Rotunno, Melissa S; Auclair, Jared R; Maniatis, Stephanie; Shaffer, Scott A; Agar, Jeffrey; Bosco, Daryl A

2014-10-10

Mutations and aberrant post-translational modifications within Cu,Zn-superoxide dismutase (SOD1) cause this otherwise protective enzyme to misfold, leading to amyotrophic lateral sclerosis (ALS). The C4F6 antibody selectively binds misfolded SOD1 in spinal cord tissues from postmortem human ALS cases, as well as from an ALS-SOD1 mouse model, suggesting that the C4F6 epitope reports on a pathogenic conformation that is common to misfolded SOD1 variants. To date, the residues and structural elements that comprise this epitope have not been elucidated. Using a chemical cross-linking and mass spectrometry approach, we identified the C4F6 epitope within several ALS-linked SOD1 variants, as well as an oxidized form of WT SOD1, supporting the notion that a similar misfolded conformation is shared among pathological SOD1 proteins. Exposure of the C4F6 epitope was modulated by the SOD1 electrostatic (loop VII) and zinc binding (loop IV) loops and correlated with SOD1-induced toxicity in a primary microglia activation assay. Site-directed mutagenesis revealed Asp(92) and Asp(96) as key residues within the C4F6 epitope required for the SOD1-C4F6 binding interaction. We propose that stabilizing the functional loops within SOD1 and/or obscuring the C4F6 epitope are viable therapeutic strategies for treating SOD1-mediated ALS. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Direct evidence for interaction between nano-anatase and superoxide dismutase from rat erythrocytes

NASA Astrophysics Data System (ADS)

Ma, Linglan; Ze, Yuguang; Liu, Jie; Liu, Huiting; Liu, Chao; Li, Zhongrui; Zhao, Jinfang; Yan, Jinying; Duan, Yanmei; Xie, Yaning; Hong, Fashui

2009-07-01

Nano-TiO2 and superoxide dismutase (SOD, EC 1.15.1.1) have been added to cosmetics and used to prevent injury of skin from UV-radiation, which might be related to the decrease of oxidative damage of skin. In previous studies we had proven that nano-anatase could increase the activity of SOD and decrease the oxidative damage in vivo. The mechanisms by which nano-anatase promoted SOD activity, however, are still not clearly understood. In the present work, nano-anatase in various concentrations was added to SOD from rat erythrocytes in vitro to gain insight into the mechanism of molecular interactions between nano-anatase and SOD by various spectral methods, suggesting that the reaction between SOD and nano-anatase was two-order, which meant that the SOD activity was greatly increased by low concentration of nano-anatase and inhibited by high concentration of nano-anatase. The spectroscopic assays suggested that the nano-anatase was determined to directly bind to SOD; the binding site of nano-anatase to SOD was 0.256 and the binding constants were 6.54 × 105 and 3.6 × 105 L mol-1; Ti was bound with three oxygen or nitrogen atoms and a sulfur atoms of amino acid residues at the Ti-O(N) and Ti-S bond lengths of 1.86 and 2.37 Å, respectively, the binding nano-anatase entirely altered the secondary structure of SOD. It implied that the nano-anatase coordination created a new metal ion-active site form in SOD, thus leading to an enhancement in SOD activity.

Comparison of Instream and Laboratory Methods of Measuring Sediment Oxygen Demand

USGS Publications Warehouse

Hall, Dennis C.; Berkas, Wayne R.

1988-01-01

Sediment oxygen demand (SOD) was determined at three sites in a gravel-bottomed central Missouri stream by: (1) two variations of an instream method, and (2) a laboratory method. SOD generally was greatest by the instream methods, which are considered more accurate, and least by the laboratory method. Disturbing stream sediment did not significantly decrease SOD by the instream method. Temperature ranges of up to 12 degree Celsius had no significant effect on the SOD. In the gravel-bottomed stream, the placement of chambers was critical to obtain reliable measurements. SOD rates were dependent on the method; therefore, care should be taken in comparing SOD data obtained by different methods. There is a need for a carefully researched standardized method for SOD determinations.

Structural, functional and immunogenic insights on Cu,Zn superoxide dismutase pathogenic virulence factors from Neisseria meningitidis and Brucella abortus

DOE PAGES

Pratt, Ashley J.; DiDonato, Michael; Shin, David S.; ...

2015-10-12

Bacterial pathogens Neisseria meningitidis and Brucella abortus pose threats to human and animal health worldwide, causing meningococcal disease and brucellosis, respectively. Mortality from acute N. meningitidis infections remains high despite antibiotics, and brucellosis presents alimentary and health consequences. Superoxide dismutases are master regulators of reactive oxygen, general pathogenicity factors and therefore therapeutic targets. Cu,Zn superoxide dismutases (SODs) localized to the periplasm promote survival by detoxifying superoxide radicals generated by major host antimicrobial immune responses. We discovered that passive immunization with an antibody directed at N. meningitidis SOD (NmSOD) was protective in a mouse infection model. To define the relevant atomicmore » details and solution assembly states of this important virulence factor, we report high-resolution and X-ray scattering analyses of NmSOD and SOD from B. abortus (BaSOD). The NmSOD structures revealed an auxiliary tetrahedral Cu-binding site bridging the dimer interface; mutational analyses suggested that this metal site contributes to protein stability, with implications for bacterial defense mechanisms. Biochemical and structural analyses informed us about electrostatic substrate guidance, dimer assembly and an exposed C-terminal epitope in the NmSOD dimer. In contrast, the monomeric BaSOD structure provided insights for extending immunogenic peptide epitopes derived from the protein. These collective results reveal unique contributions of SOD to pathogenic virulence, refine predictive motifs for distinguishing SOD classes and suggest general targets for anti-bacterial immune responses. The identified functional contributions, motifs, and targets distinguishing bacterial and eukaryotic SOD assemblies presented here provide a foundation for efforts to develop SOD-specific inhibitors or vaccines against these harmful pathogens. IMPORTANCE By protecting microbes against reactive oxygen insults, Cu,Zn superoxide dismutases (SODs) aid survival of many bacteria within their hosts. Despite the ubiquity and conservation of these key enzymes, notable species-specific differences relevant to pathogenesis remain undefined. To probe mechanisms that govern the functioning of Neisseria meningitidis and Brucella abortus SODs, we used X-ray structures, enzymology, modeling and murine infection experiments. We identified virulence determinants common to both homologs, assembly differences and a unique metal reservoir within meningococcal SOD that stabilizes the enzyme and may provide a safeguard against copper toxicity. The insights reported here provide a rationale and basis for SOD-specific drugs and extension of immunogen design to target two important pathogens that continue to pose global health threats.« less

Structural, Functional, and Immunogenic Insights on Cu,Zn Superoxide Dismutase Pathogenic Virulence Factors from Neisseria meningitidis and Brucella abortus

PubMed Central

Pratt, Ashley J.; DiDonato, Michael; Shin, David S.; Cabelli, Diane E.; Bruns, Cami K.; Belzer, Carol A.; Gorringe, Andrew R.; Langford, Paul R.; Tabatabai, Louisa B.; Kroll, J. Simon; Tainer, John A.

2015-01-01

ABSTRACT Bacterial pathogens Neisseria meningitidis and Brucella abortus pose threats to human and animal health worldwide, causing meningococcal disease and brucellosis, respectively. Mortality from acute N. meningitidis infections remains high despite antibiotics, and brucellosis presents alimentary and health consequences. Superoxide dismutases are master regulators of reactive oxygen and general pathogenicity factors and are therefore therapeutic targets. Cu,Zn superoxide dismutases (SODs) localized to the periplasm promote survival by detoxifying superoxide radicals generated by major host antimicrobial immune responses. We discovered that passive immunization with an antibody directed at N. meningitidis SOD (NmSOD) was protective in a mouse infection model. To define the relevant atomic details and solution assembly states of this important virulence factor, we report high-resolution and X-ray scattering analyses of NmSOD and of SOD from B. abortus (BaSOD). The NmSOD structures revealed an auxiliary tetrahedral Cu-binding site bridging the dimer interface; mutational analyses suggested that this metal site contributes to protein stability, with implications for bacterial defense mechanisms. Biochemical and structural analyses informed us about electrostatic substrate guidance, dimer assembly, and an exposed C-terminal epitope in the NmSOD dimer. In contrast, the monomeric BaSOD structure provided insights for extending immunogenic peptide epitopes derived from the protein. These collective results reveal unique contributions of SOD to pathogenic virulence, refine predictive motifs for distinguishing SOD classes, and suggest general targets for antibacterial immune responses. The identified functional contributions, motifs, and targets distinguishing bacterial and eukaryotic SOD assemblies presented here provide a foundation for efforts to develop SOD-specific inhibitors of or vaccines against these harmful pathogens. IMPORTANCE By protecting microbes against reactive oxygen insults, SODs aid survival of many bacteria within their hosts. Despite the ubiquity and conservation of these key enzymes, notable species-specific differences relevant to pathogenesis remain undefined. To probe mechanisms that govern the functioning of Neisseria meningitidis and Brucella abortus SODs, we used X-ray structures, enzymology, modeling, and murine infection experiments. We identified virulence determinants common to the two homologs, assembly differences, and a unique metal reservoir within meningococcal SOD that stabilizes the enzyme and may provide a safeguard against copper toxicity. The insights reported here provide a rationale and a basis for SOD-specific drug design and an extension of immunogen design to target two important pathogens that continue to pose global health threats. PMID:26459556

Structural, Functional, and Immunogenic Insights on Cu,Zn Superoxide Dismutase Pathogenic Virulence Factors from Neisseria meningitidis and Brucella abortus.

PubMed

Pratt, Ashley J; DiDonato, Michael; Shin, David S; Cabelli, Diane E; Bruns, Cami K; Belzer, Carol A; Gorringe, Andrew R; Langford, Paul R; Tabatabai, Louisa B; Kroll, J Simon; Tainer, John A; Getzoff, Elizabeth D

2015-12-01

Bacterial pathogens Neisseria meningitidis and Brucella abortus pose threats to human and animal health worldwide, causing meningococcal disease and brucellosis, respectively. Mortality from acute N. meningitidis infections remains high despite antibiotics, and brucellosis presents alimentary and health consequences. Superoxide dismutases are master regulators of reactive oxygen and general pathogenicity factors and are therefore therapeutic targets. Cu,Zn superoxide dismutases (SODs) localized to the periplasm promote survival by detoxifying superoxide radicals generated by major host antimicrobial immune responses. We discovered that passive immunization with an antibody directed at N. meningitidis SOD (NmSOD) was protective in a mouse infection model. To define the relevant atomic details and solution assembly states of this important virulence factor, we report high-resolution and X-ray scattering analyses of NmSOD and of SOD from B. abortus (BaSOD). The NmSOD structures revealed an auxiliary tetrahedral Cu-binding site bridging the dimer interface; mutational analyses suggested that this metal site contributes to protein stability, with implications for bacterial defense mechanisms. Biochemical and structural analyses informed us about electrostatic substrate guidance, dimer assembly, and an exposed C-terminal epitope in the NmSOD dimer. In contrast, the monomeric BaSOD structure provided insights for extending immunogenic peptide epitopes derived from the protein. These collective results reveal unique contributions of SOD to pathogenic virulence, refine predictive motifs for distinguishing SOD classes, and suggest general targets for antibacterial immune responses. The identified functional contributions, motifs, and targets distinguishing bacterial and eukaryotic SOD assemblies presented here provide a foundation for efforts to develop SOD-specific inhibitors of or vaccines against these harmful pathogens. By protecting microbes against reactive oxygen insults, SODs aid survival of many bacteria within their hosts. Despite the ubiquity and conservation of these key enzymes, notable species-specific differences relevant to pathogenesis remain undefined. To probe mechanisms that govern the functioning of Neisseria meningitidis and Brucella abortus SODs, we used X-ray structures, enzymology, modeling, and murine infection experiments. We identified virulence determinants common to the two homologs, assembly differences, and a unique metal reservoir within meningococcal SOD that stabilizes the enzyme and may provide a safeguard against copper toxicity. The insights reported here provide a rationale and a basis for SOD-specific drug design and an extension of immunogen design to target two important pathogens that continue to pose global health threats. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Structural, functional and immunogenic insights on Cu,Zn superoxide dismutase pathogenic virulence factors from Neisseria meningitidis and Brucella abortus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pratt, Ashley J.; DiDonato, Michael; Shin, David S.

Bacterial pathogens Neisseria meningitidis and Brucella abortus pose threats to human and animal health worldwide, causing meningococcal disease and brucellosis, respectively. Mortality from acute N. meningitidis infections remains high despite antibiotics, and brucellosis presents alimentary and health consequences. Superoxide dismutases are master regulators of reactive oxygen, general pathogenicity factors and therefore therapeutic targets. Cu,Zn superoxide dismutases (SODs) localized to the periplasm promote survival by detoxifying superoxide radicals generated by major host antimicrobial immune responses. We discovered that passive immunization with an antibody directed at N. meningitidis SOD (NmSOD) was protective in a mouse infection model. To define the relevant atomicmore » details and solution assembly states of this important virulence factor, we report high-resolution and X-ray scattering analyses of NmSOD and SOD from B. abortus (BaSOD). The NmSOD structures revealed an auxiliary tetrahedral Cu-binding site bridging the dimer interface; mutational analyses suggested that this metal site contributes to protein stability, with implications for bacterial defense mechanisms. Biochemical and structural analyses informed us about electrostatic substrate guidance, dimer assembly and an exposed C-terminal epitope in the NmSOD dimer. In contrast, the monomeric BaSOD structure provided insights for extending immunogenic peptide epitopes derived from the protein. These collective results reveal unique contributions of SOD to pathogenic virulence, refine predictive motifs for distinguishing SOD classes and suggest general targets for anti-bacterial immune responses. The identified functional contributions, motifs, and targets distinguishing bacterial and eukaryotic SOD assemblies presented here provide a foundation for efforts to develop SOD-specific inhibitors or vaccines against these harmful pathogens. IMPORTANCE By protecting microbes against reactive oxygen insults, Cu,Zn superoxide dismutases (SODs) aid survival of many bacteria within their hosts. Despite the ubiquity and conservation of these key enzymes, notable species-specific differences relevant to pathogenesis remain undefined. To probe mechanisms that govern the functioning of Neisseria meningitidis and Brucella abortus SODs, we used X-ray structures, enzymology, modeling and murine infection experiments. We identified virulence determinants common to both homologs, assembly differences and a unique metal reservoir within meningococcal SOD that stabilizes the enzyme and may provide a safeguard against copper toxicity. The insights reported here provide a rationale and basis for SOD-specific drugs and extension of immunogen design to target two important pathogens that continue to pose global health threats.« less

Import, maturation, and function of SOD1 and its copper chaperone CCS in the mitochondrial intermembrane space.

PubMed

Kawamata, Hibiki; Manfredi, Giovanni

2010-11-01

Cu, Zn, superoxide dismutase (SOD1) is a ubiquitous enzyme localized in multiple cellular compartments, including mitochondria, where it concentrates in the intermembrane space (IMS). Similar to other small IMS proteins, the import and retention of SOD1 in the IMS is linked to its folding and maturation, involving the formation of critical intra- and intermolecular disulfide bonds. Therefore, the cysteine residues of SOD1 play a fundamental role in its IMS localization. IMS import of SOD1 involves its copper chaperone, CCS, whose mitochondrial distribution is regulated by the Mia40/Erv1 disulfide relay system in a redox-dependent manner: CCS promotes SOD1 maturation and retention in the IMS. The function of SOD1 in the IMS is still unknown, but it is plausible that it serves to remove superoxide released from the mitochondrial respiratory chain. Mutations in SOD1 cause familial amyotrophic lateral sclerosis (ALS), whose pathologic features include mitochondrial bioenergetic dysfunction. Mutant SOD1 localization in the IMS is not dictated by oxygen concentration and the Mia40/Erv1 system, but is primarily dependent on aberrant protein folding and aggregation. Mutant SOD1 localization and aggregation in the IMS might cause the mitochondrial abnormalities observed in familial ALS and could play a significant role in disease pathogenesis.

Novel dimeric interface and electrostatic recognition in bacterial Cu,Zn superoxide dismutase

PubMed Central

Bourne, Yves; Redford, Susan M.; Steinman, Howard M.; Lepock, James R.; Tainer, John A.; Getzoff, Elizabeth D.

1996-01-01

Eukaryotic Cu,Zn superoxide dismutases (CuZnSODs) are antioxidant enzymes remarkable for their unusually stable β-barrel fold and dimer assembly, diffusion-limited catalysis, and electrostatic guidance of their free radical substrate. Point mutations of CuZnSOD cause the fatal human neurodegenerative disease amyotrophic lateral sclerosis. We determined and analyzed the first crystallographic structure (to our knowledge) for CuZnSOD from a prokaryote, Photobacterium leiognathi, a luminescent symbiont of Leiognathid fish. This structure, exemplifying prokaryotic CuZnSODs, shares the active-site ligand geometry and the topology of the Greek key β-barrel common to the eukaryotic CuZnSODs. However, the β-barrel elements recruited to form the dimer interface, the strategy used to forge the channel for electrostatic recognition of superoxide radical, and the connectivity of the intrasubunit disulfide bond in P. leiognathi CuZnSOD are discrete and strikingly dissimilar from those highly conserved in eukaryotic CuZnSODs. This new CuZnSOD structure broadens our understanding of structural features necessary and sufficient for CuZnSOD activity, highlights a hitherto unrecognized adaptability of the Greek key β-barrel building block in evolution, and reveals that prokaryotic and eukaryotic enzymes diverged from one primordial CuZnSOD and then converged to distinct dimeric enzymes with electrostatic substrate guidance. PMID:8917495

Sod1 Loss Induces Intrinsic Superoxide Accumulation Leading to p53-Mediated Growth Arrest and Apoptosis

PubMed Central

Watanabe, Kenji; Shibuya, Shuichi; Koyama, Hirofumi; Ozawa, Yusuke; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

2013-01-01

Oxidative damages induced by a redox imbalance cause age-related changes in cells and tissues. Superoxide dismutase (SOD) enzymes play a major role in the antioxidant system and they also catalyze superoxide radicals (O2•−). Since the loss of cytoplasmic SOD (SOD1) resulted in aging-like phenotypes in several types of mouse tissue, SOD1 is essential for the maintenance of tissue homeostasis. To clarify the cellular function of SOD1, we investigated the cellular phenotypes of Sod1-deficient fibroblasts. We demonstrated that Sod1 deficiency impaired proliferation and induced apoptosis associated with O2•− accumulation in the cytoplasm and mitochondria in fibroblasts. Sod1 loss also decreased the mitochondrial membrane potential and led to DNA damage-mediated p53 activation. Antioxidant treatments effectively improved the cellular phenotypes through suppression of both intracellular O2•− accumulation and p53 activation in Sod1-deficient fibroblasts. In vivo experiments revealed that transdermal treatment with a vitamin C derivative significantly reversed the skin thinning commonly associated with the upregulated p53 action in the skin. Our findings revealed that intrinsic O2•− accumulation promoted p53-mediated growth arrest and apoptosis as well as mitochondrial disfunction in the fibroblasts. PMID:23708100

The expression of superoxide dismutase in Mytilus coruscus under various stressors.

PubMed

Wu, Jiong; Bao, Miaomiao; Ge, Delong; Huo, Liping; Lv, Zhenming; Chi, Changfeng; Liao, Zhi; Liu, Huihui

2017-11-01

Superoxide dismutases (SODs), a by-product of antioxidative defence system, protects organisms for eliminating excess reactive oxygen species (ROS) and maintaining the redox balance of immune system. The complete open reading frames (ORFs) of Cu/Zn-SOD and Mn-SOD were identified from Mytilus coruscus (designated as McSOD and MnSOD) by homologous cloning. The sequence lengths were 474bp and 687bp, encoding 157 and 228 amino acids respectively. The deduced amino acid sequences of McSOD and MnSOD shared high identities with Cu/Zn-SOD and Mn-SOD from other mollusca. The distributions of McSOD and MnSOD were detected in six tissues including adductor, hemocyte, gill, gonad, mantle and hepatopancreas, and the highest expressions were both in gills. The temporal expression of McSOD and MnSOD were up-regulated in gills under a variety of stress factors, including Vibrio parahemolyticus, Aeromonas hydrophila, Cu 2+ and Pb 2+ . After being challenged with V. Parahemolyticus, the expressions of McSOD and MnSOD were increased rapidly at the initial hours, reaching the peaks of 4.9-fold and 15.3-fold respectively, and got to the highest levels of 43.5-fold and 7.1-fold after being challenged with A. hydrophila. The highest point of McSOD mRNA appeared at 15 d after being exposed to copper (7-fold at 0.5 mg/L and 13.2-fold at 1.5 mg/L), except for 0.1 mg/L group of Cu 2+ maintaining to the normal level, but plumbum at 1 d (2.4-fold at 1.0 mg/L and 4.4-fold at 3.0 mg/L) and at 15 d (2.1-fold at 0.2 mg/L). The temporal expression peaks of MnSOD appeared differently after exposing to copper of various concentrations (0.1 mg/L at 10 d with 4.7-fold, 0.5 mg/L at 1 d with 17.9-fold and 1.5 mg/L at 3 d with 13.2-fold). Whereas in plumbum exposing treatments, the 3.0 mg/L group jumped to the peak at 1 d (18.2-fold), the 0.2 mg/L and 1.0 mg/L groups had little change and maintained at the normal level throughout the experiment. The results provided several new evidences for further understanding of the regulatory mechanism of SOD on the innate immune system in bivalve. Copyright © 2017 Elsevier Ltd. All rights reserved.

Postmitotic Expression of SOD1G93A Gene Affects the Identity of Myogenic Cells and Inhibits Myoblasts Differentiation

PubMed Central

Martini, Martina; Dobrowolny, Gabriella; Aucello, Michela; Musarò, Antonio

2015-01-01

To determine the role of mutant SOD1 gene (SOD1G93A) on muscle cell differentiation, we derived C2C12 muscle cell lines carrying a stably transfected SOD1G93A gene under the control of a myosin light chain (MLC) promoter-enhancer cassette. Expression of MLC/SOD1G93A in C2C12 cells resulted in dramatic inhibition of myoblast differentiation. Transfected SOD1G93A gene expression in postmitotic skeletal myocytes downregulated the expression of relevant markers of committed and differentiated myoblasts such as MyoD, Myogenin, MRF4, and the muscle specific miRNA expression. The inhibitory effects of SOD1G93A gene on myogenic program perturbed Akt/p70 and MAPK signaling pathways which promote differentiation cascade. Of note, the inhibition of the myogenic program, by transfected SOD1G93A gene expression, impinged also the identity of myogenic cells. Expression of MLC/SOD1G93A in C2C12 myogenic cells promoted a fibro-adipogenic progenitors (FAPs) phenotype, upregulating HDAC4 protein and preventing the myogenic commitment complex BAF60C-SWI/SNF. We thus identified potential molecular mediators of the inhibitory effects of SOD1G93A on myogenic program and disclosed potential signaling, activated by SOD1G93A, that affect the identity of the myogenic cell population. PMID:26491230

Postmitotic Expression of SOD1(G93A) Gene Affects the Identity of Myogenic Cells and Inhibits Myoblasts Differentiation.

PubMed

Martini, Martina; Dobrowolny, Gabriella; Aucello, Michela; Musarò, Antonio

2015-01-01

To determine the role of mutant SOD1 gene (SOD1(G93A)) on muscle cell differentiation, we derived C2C12 muscle cell lines carrying a stably transfected SOD1(G93A) gene under the control of a myosin light chain (MLC) promoter-enhancer cassette. Expression of MLC/SOD1(G93A) in C2C12 cells resulted in dramatic inhibition of myoblast differentiation. Transfected SOD1(G93A) gene expression in postmitotic skeletal myocytes downregulated the expression of relevant markers of committed and differentiated myoblasts such as MyoD, Myogenin, MRF4, and the muscle specific miRNA expression. The inhibitory effects of SOD1(G93A) gene on myogenic program perturbed Akt/p70 and MAPK signaling pathways which promote differentiation cascade. Of note, the inhibition of the myogenic program, by transfected SOD1(G93A) gene expression, impinged also the identity of myogenic cells. Expression of MLC/SOD1(G93A) in C2C12 myogenic cells promoted a fibro-adipogenic progenitors (FAPs) phenotype, upregulating HDAC4 protein and preventing the myogenic commitment complex BAF60C-SWI/SNF. We thus identified potential molecular mediators of the inhibitory effects of SOD1(G93A) on myogenic program and disclosed potential signaling, activated by SOD1(G93A), that affect the identity of the myogenic cell population.

Identification of novel superoxide dismutase isoenzymes in the olive (Olea europaea L.) pollen.

PubMed

Zafra, Adoración; Castro, Antonio Jesús; Alché, Juan de Dios

2018-06-08

Among antioxidant enzymes, the superoxide dismutase (SOD) family is a major actor in catalysing the disproportionation of superoxide. Apart from its role as antioxidant, these enzymes have a role in cell signalling, and Cu,Zn-SOD proteins are also major pollen allergens. In order to deepen our understanding of the SOD isoenzymes present in olive pollen and to analyse the molecular variability of the pollen Cu,Zn-SOD family, we carried out biochemical, transcriptomic and localization studies of pollen grains from different olive cultivars and other allergenic species. Olive pollen showed a high rate of total SOD activity in all cultivars assayed, which did not correlate with pollen viability. Mass spectrometry analysis together with activity assays and Western blotting experiments enabled us to identify new forms of Cu,Zn-SOD enzyme (including chloroplastidic and peroxisomal forms) as well as differentially expressed Mn-, Fe- and Cu,Zn-SOD isoenzymes among the pollen of different olive cultivars and allergenic species. Ultrastructural localization of Cu,Zn-SOD revealed its plastidial localization in the pollen grain. We also identified the occurrence of a shorter form of one of the cytosolic Cu,Zn-SOD enzymes, likely as the result of alternative splicing. This shorter enzyme showed lower SOD activity as compared to the full length form. The presence of multiple SOD isoenzymes in the olive pollen could be related to the need of finely tuning the ROS metabolism during the transition from its quiescent condition at maturity to a highly metabolically active state at germination.

Using reinforced native grass sod for biostrips, bioswales, and sediment control.

DOT National Transportation Integrated Search

2008-12-01

The objective of this research was to develop and demonstrate native grass sod for sediment control from disturbed lands associated with California highways. The research evaluated native grass species for inclusion in sod and evaluated the sod at a ...

HoxB2 binds mutant SOD1 and is altered in transgenic model of ALS.

PubMed

Zhai, Jinbin; Lin, Hong; Canete-Soler, Rafaela; Schlaepfer, William W

2005-09-15

Mutations in Cu/Zn superoxide dismutase (SOD1) cause approximately 20% of familial amyotrophic lateral sclerosis by a toxic gain of function; however, the precise mechanisms remain unclear. Here, we report the identification of HoxB2, a homeodomain-containing transcription factor, as a G93A mutant SOD1 interactive protein in a yeast two-hybrid screen. We show that HoxB2 co-precipitates and co-localizes with mutant SOD1 in neuronal cell lines, as well as in brain and spinal cord of G93A mutant SOD1 transgenic mice. Mutagenesis further shows that this interaction is mediated by the central homeodomain of HoxB2. In motor neuron-like NSC-34 cells, overexpression of HoxB2 or its homeodomain decreases the insolubility of mutant SOD1 and inhibits G93A or G86R mutant SOD1-induced neuronal cell death. In human and mouse tissues, we show that expression of HoxB2 persists in adult spinal cord and is primarily localized in nuclei of motor neurons. In G93A transgenic mice, HoxB2 co-localizes with mutant SOD1 and is redistributed to perikarya and proximal neurites of motor neurons. In addition, there is progressive accumulation of HoxB2 and mutant SOD1 as punctate inclusions in the neuropil surrounding motor neurons. Taken together, our findings demonstrate that interaction of HoxB2 with mutant SOD1 occurs in motor neurons of G93A mutant SOD1 transgenic mice and suggest that this interaction may modulate the neurotoxicity of mutant SOD1.

A manganese-rich environment supports superoxide dismutase activity in a Lyme disease pathogen, Borrelia burgdorferi.

PubMed

Aguirre, J Dafhne; Clark, Hillary M; McIlvin, Matthew; Vazquez, Christine; Palmere, Shaina L; Grab, Dennis J; Seshu, J; Hart, P John; Saito, Mak; Culotta, Valeria C

2013-03-22

The Lyme disease pathogen Borrelia burgdorferi represents a novel organism in which to study metalloprotein biology in that this spirochete has uniquely evolved with no requirement for iron. Not only is iron low, but we show here that B. burgdorferi has the capacity to accumulate remarkably high levels of manganese. This high manganese is necessary to activate the SodA superoxide dismutase (SOD) essential for virulence. Using a metalloproteomic approach, we demonstrate that a bulk of B. burgdorferi SodA directly associates with manganese, and a smaller pool of inactive enzyme accumulates as apoprotein. Other metalloproteins may have similarly adapted to using manganese as co-factor, including the BB0366 aminopeptidase. Whereas B. burgdorferi SodA has evolved in a manganese-rich, iron-poor environment, the opposite is true for Mn-SODs of organisms such as Escherichia coli and bakers' yeast. These Mn-SODs still capture manganese in an iron-rich cell, and we tested whether the same is true for Borrelia SodA. When expressed in the iron-rich mitochondria of Saccharomyces cerevisiae, B. burgdorferi SodA was inactive. Activity was only possible when cells accumulated extremely high levels of manganese that exceeded cellular iron. Moreover, there was no evidence for iron inactivation of the SOD. B. burgdorferi SodA shows strong overall homology with other members of the Mn-SOD family, but computer-assisted modeling revealed some unusual features of the hydrogen bonding network near the enzyme's active site. The unique properties of B. burgdorferi SodA may represent adaptation to expression in the manganese-rich and iron-poor environment of the spirochete.

Molecular characterization of a cDNA encoding copper/zinc superoxide dismutase from cultured cells of Manihot esculenta.

PubMed

Shin, Seung-Yong; Lee, Haeng-Soon; Kwon, Suk-Yoon; Kwon, Soon-Tae; Kwak, Sang-Soo

2005-01-01

Superoxide dismutase (SOD) cDNA, mSOD2, encoding cytosolic copper/zinc SOD (CuZnSOD) cDNA was isolated from suspension-cultured cells of cassava (Manihot esculenta Crantz) by cDNA library screening, and its expression was investigated in relation to environmental stress. mSOD2 is 774 bp in length with an open reading frame (ORF) of 152 amino acids, corresponding to a protein of predicted molecular mass 15 kDa and a pI of 5.22. One copy of the mSOD2 gene was found to be present in the cassava genome by Southern analysis using an mSOD2 cDNA-specific probe. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis revealed diverse expression patterns for the mSOD2 gene in various tissues of intact cassava plants, at various stages of the growth in suspension cultures, and in the leaf tissues exposed to different stresses. The mSOD2 gene was highly expressed in suspension-cultured cells and in the stems of intact plants. However, it was expressed at low levels in leaves and roots. During suspension cell growth, the mSOD2 transcript progressively increased during culture. Moreover, the mSOD2 gene in excised cassava leaves responded to various stresses in different ways. In particular, it was highly induced in leaf tissue by several abiotic stresses, including high temperature (37 degrees C), chilling (4 degrees C), methyl viologen (MV) exposure, and wounding treatment. These results indicate that the mSOD2 gene is involved in the antioxidative process triggered by oxidative stress induced by environmental change.

Cu,Zn superoxide dismutase: cloning and analysis of the Taenia solium gene and Taenia crassiceps cDNA.

PubMed

Parra-Unda, Ricardo; Vaca-Paniagua, Felipe; Jiménez, Lucia; Landa, Abraham

2012-01-01

Cytosolic Cu,Zn superoxide dismutase (Cu,Zn-SOD) catalyzes the dismutation of superoxide (O(2)(-)) to oxygen and hydrogen peroxide (H(2)O(2)) and plays an important role in the establishment and survival of helminthes in their hosts. In this work, we describe the Taenia solium Cu,Zn-SOD gene (TsCu,Zn-SOD) and a Taenia crassiceps (TcCu,Zn-SOD) cDNA. TsCu,Zn-SOD gene that spans 2.841 kb, and has three exons and two introns; the splicing junctions follow the GT-AG rule. Analysis in silico of the gene revealed that the 5'-flanking region has three putative TATA and CCAAT boxes, and transcription factor binding sites for NF1 and AP1. The transcription start site was a C, located at 22 nucleotides upstream of the translation start codon (ATG). Southern blot analysis showed that TcCu,Zn-SOD and TsCu,Zn-SOD genes are encoded by a single copy. The deduced amino acid sequences of TsCu,Zn-SOD gene and TcCu,Zn-SOD cDNA reveal 98.47% of identity, and the characteristic motives, including the catalytic site and β-barrel structure of the Cu,Zn-SOD. Proteomic and immunohistochemical analysis indicated that Cu,Zn-SOD does not have isoforms, is distributed throughout the bladder wall and is concentrated in the tegument of T. solium and T. crassiceps cysticerci. Expression analysis revealed that TcCu,Zn-SOD mRNA and protein expression levels do not change in cysticerci, even upon exposure to O(2)(-) (0-3.8 nmol/min) and H(2)O(2) (0-2mM), suggesting that this gene is constitutively expressed in these parasites. Published by Elsevier Inc.

ALS mutant SOD1 interacts with G3BP1 and affects stress granule dynamics.

PubMed

Gal, Jozsef; Kuang, Lisha; Barnett, Kelly R; Zhu, Brian Z; Shissler, Susannah C; Korotkov, Konstantin V; Hayward, Lawrence J; Kasarskis, Edward J; Zhu, Haining

2016-10-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Mutations in Cu/Zn superoxide dismutase (SOD1) are responsible for approximately 20 % of the familial ALS cases. ALS-causing SOD1 mutants display a gain-of-toxicity phenotype, but the nature of this toxicity is still not fully understood. The Ras GTPase-activating protein-binding protein G3BP1 plays a critical role in stress granule dynamics. Alterations in the dynamics of stress granules have been reported in several other forms of ALS unrelated to SOD1. To our surprise, the mutant G93A SOD1 transgenic mice exhibited pathological cytoplasmic inclusions that co-localized with G3BP1-positive granules in spinal cord motor neurons. The co-localization was also observed in fibroblast cells derived from familial ALS patient carrying SOD1 mutation L144F. Mutant SOD1, unlike wild-type SOD1, interacted with G3BP1 in an RNA-independent manner. Moreover, the interaction is specific for G3BP1 since mutant SOD1 showed little interaction with four other RNA-binding proteins implicated in ALS. The RNA-binding RRM domain of G3BP1 and two particular phenylalanine residues (F380 and F382) are critical for this interaction. Mutant SOD1 delayed the formation of G3BP1- and TIA1-positive stress granules in response to hyperosmolar shock and arsenite treatment in N2A cells. In summary, the aberrant mutant SOD1-G3BP1 interaction affects stress granule dynamics, suggesting a potential link between pathogenic SOD1 mutations and RNA metabolism alterations in ALS.

Implications of fALS Mutations on Sod1 Function and Oligomerization in Cell Models.

PubMed

Brasil, Aline A; Magalhães, Rayne S S; De Carvalho, Mariana D C; Paiva, Isabel; Gerhardt, Ellen; Pereira, Marcos D; Outeiro, Tiago F; Eleutherio, Elis C A

2018-06-01

Among the familial forms of amyotrophic lateral sclerosis (fALS), 20% are associated with the Cu,Zn-superoxide dismutase (Sod1). fALS is characterized by the accumulation of aggregated proteins and the increase in oxidative stress markers. Here, we used the non-invasive bimolecular fluorescence complementation (BiFC) assay in human H4 cells to investigate the kinetics of aggregation and subcellular localization of Sod1 mutants. We also studied the effect of the different Sod1 mutants to respond against oxidative stress by following the levels of reactive oxygen species (ROS) after treatment with hydrogen peroxide. Our results showed that only 30% of cells transfected with A4VSod1 showed no inclusions while for the other Sod1 mutants tested (L38V, G93A and G93C), this percentage was at least 70%. In addition, we found that 10% of cells transfected with A4VSod1 displayed more than five inclusions per cell and that A4V and G93A Sod1 formed inclusions more rapidly than L38V and G93C Sod1. Expression of WTSod1 significantly decreased the intracellular oxidation levels in comparison with expression of fALS Sod1 mutants, suggesting the mutations induce a functional impairment. All fALS mutations impaired nuclear localization of Sod1, which is important for maintaining genomic stability. Consistently, expression of WTSod1, but not of fALS Sod1 mutants, reduced DNA damage, as measured by the comet assay. Altogether, our study sheds light into the effects of fALS Sod1 mutations on inclusion formation, dynamics, and localization as well as on antioxidant response, opening novel avenues for investigating the role of fALS Sod1 mutations in pathogenesis.

Selective decontamination of the digestive tract and selective oropharyngeal decontamination in intensive care unit patients: a cost-effectiveness analysis.

PubMed

Oostdijk, Evelien A N; de Wit, G A; Bakker, Marina; de Smet, Anne Marie G A; Bonten, M J M

2013-03-05

To determine costs and effects of selective digestive tract decontamination (SDD) and selective oropharyngeal decontamination (SOD) as compared with standard care (ie, no SDD/SOD (SC)) from a healthcare perspective in Dutch Intensive Care Units (ICUs). A post hoc analysis of a previously performed cluster-randomised trial (NEJM 2009;360:20). 13 Dutch ICUs. Patients with ICU-stay of >48 h that received SDD (n=2045), SOD (n=1904) or SC (n=1990). SDD or SOD. Effects were based on hospital survival, expressed as crude Life Years Gained (cLYG). The incremental cost-effectiveness ratio (ICER) was calculated, with corresponding cost acceptability curves. Sensitivity analyses were performed for discount rates, costs of SDD, SOD and mechanical ventilation. Total costs per patient were €41 941 for SC (95% CI €40 184 to €43 698), €40 433 for SOD (95% CI €38 838 to €42 029) and €41 183 for SOD (95% CI €39 408 to €42 958). SOD and SDD resulted in crude LYG of +0.04 and +0.25, respectively, as compared with SC, implying that both SDD and SOD are dominant (ie, cheaper and more beneficial) over SC. In cost-effectiveness acceptability curves probabilities for cost-effectiveness, compared with standard care, ranged from 89% to 93% for SOD and from 63% to 72% for SDD, for acceptable costs for 1 LYG ranging from €0 to €20 000. Sensitivity analysis for mechanical ventilation and discount rates did not change interpretation. Yet, if costs of the topical component of SDD and SOD would increase 40-fold to €400/day and €40/day (maximum values based on free market prices in 2012), the estimated ICER as compared with SC for SDD would be €21 590 per LYG. SOD would remain cost-saving. SDD and SOD were both effective and cost-saving in Dutch ICUs.

Transcript profiles of mitochondrial and cytoplasmic manganese superoxide dismutases in Exopalaemon carinicauda under ammonia stress

NASA Astrophysics Data System (ADS)

Ren, Hai; Li, Jian; Li, Jitao; Liu, Ping; Liang, Zhongxiu; Wu, Jianhua

2015-05-01

Superoxide dismutase (SOD) is one of the most important antioxidant defense enzymes, and is considered as the first line against oxidative stress. In this study, we cloned a mitochondrial manganese (Mn) SOD ( mMnSOD) cDNA from the ridgetail white prawn Exopalaemon carinicauda by using rapid amplification of cDNA ends (RACE) methods. The full-length cDNA for mMnSOD was 1 014-bp long, containing a 5'-untranslated region (UTR) of 37-bp, a 3'-UTR of 321-bp with a poly (A) tail, and included a 657-bp open reading frame encoding a protein of 218 amino acids with a 16-amino-acid signal peptide. The protein had a calculated molecular weight of 23.87 kDa and a theoretical isoelectric point of 6.75. The mMnSOD sequence included two putative N-glycosylation sites (NHT and NLS), the MnSOD signature sequence 180DVWEHAYY187, and four putative Mn binding sites (H48, H96, D180, and H184). Sequence comparison showed that the mMnSOD deduced amino acid sequence of E. carinicauda shared 97%, 95%, 89%, 84%, 82%, 72%, and 69% identity with that of Macrobrachium rosenbergii, Macrobrachium nipponense, Fenneropeneaus chinensis, Callinectes sapidus, Perisesarma bidens, Danio rerio, and Homo sapiens, resectively. Quantitative real-time RT-PCR analysis showed that mMnSOD transcripts were present in all E. carinicauda tissues examined, with the highest levels in the hepatopancreas. During an ammonia stress treatment, the transcript levels of mMnSOD and cMnSOD were up-regulated at 12 h in hemocytes and at 24 h in the hepatopancreas. As the duration of the ammonia stress treatment extended to 72 h, the transcript levels of mMnSOD and cMnSOD significantly decreased both in hemocytes and hepatopancreas. These findings indicate that the SOD system is induced to respond to acute ammonia stress, and may be involved in environmental stress responses in E. carinicauda.

Glycerolipid Headgroups Control Rate and Mechanism of Superoxide Dismutase-1 Aggregation and Accelerate Fibrillization of Slowly Aggregating Amyotrophic Lateral Sclerosis Mutants.

PubMed

Rasouli, Sanaz; Abdolvahabi, Alireza; Croom, Corbin M; Plewman, Devon L; Shi, Yunhua; Shaw, Bryan F

2018-04-20

Interactions between superoxide dismutase-1 (SOD1) and lipid membranes might be directly involved in the toxicity and intercellular propagation of aggregated SOD1 in amyotrophic lateral sclerosis (ALS), but the chemical details of lipid-SOD1 interactions and their effects on SOD1 aggregation remain unclear. This paper determined the rate and mechanism of nucleation of fibrillar apo-SOD1 catalyzed by liposomal surfaces with identical hydrophobic chains (RCH 2 (O 2 C 18 H 33 ) 2 ), but headgroups of different net charge and hydrophobicity (i.e., R(CH 2 )N + (CH 3 ) 3 , RPO 4 - (CH 2 ) 2 N + (CH 3 ) 3 , and RPO 4 - ). Under semiquiescent conditions (within a 96 well microplate, without a gyrating bead), the aggregation of apo-SOD1 into thioflavin-T-positive (ThT(+)) amyloid fibrils did not occur over 120 h in the absence of liposomal surfaces. Anionic liposomes triggered aggregation of apo-SOD1 into ThT(+) amyloid fibrils; cationic liposomes catalyzed fibrillization but at slower rates and across a narrower lipid concentration; zwitterionic liposomes produced nonfibrillar (amorphous) aggregates. The inability of zwitterionic liposomes to catalyze fibrillization and the dependence of fibrillization rate on anionic lipid concentration suggests that membranes catalyze SOD1 fibrillization by a primary nucleation mechanism. Membrane-catalyzed fibrillization was also examined for eight ALS variants of apo-SOD1, including G37R, G93R, D90A, and E100G apo-SOD1 that nucleate slower than or equal to WT SOD1 in lipid-free, nonquiescent amyloid assays. All ALS variants (with one exception) nucleated faster than WT SOD1 in the presence of anionic liposomes, wherein the greatest acceleratory effects were observed among variants with lower net negative surface charge (G37R, G93R, D90A, E100G). The exception was H46R apo-SOD1, which did not form ThT(+) species.

Interleukin-1beta and interleukin-6 disturb the antioxidant enzyme system in bovine chondrocytes: a possible explanation for oxidative stress generation.

PubMed

Mathy-Hartert, M; Hogge, L; Sanchez, C; Deby-Dupont, G; Crielaard, J M; Henrotin, Y

2008-07-01

Beside matrix metalloproteinases, reactive oxygen species (ROS) are the main biochemical factors of cartilage degradation. To prevent ROS toxicity, chondrocytes possess a well-coordinated enzymatic antioxidant system formed principally by superoxide dismutases (SODs), catalase (CAT) and glutathione peroxidase (GPX). This work was designed to assess the effects of interleukin (IL)-1beta and IL-6 on the enzymatic activity and gene expression of SODs, CAT and GPX in bovine chondrocytes. Bovine chondrocytes were cultured in monolayer for 4-96 h in the absence or in the presence of IL-1beta (0.018-1.8ng/ml) or IL-6 (10-100 ng/ml). To study signal transduction pathway, inhibitors of mitogen-activated protein kinases (MAPK) (PD98059, SB203580 and SP600125) (5-20 microM) and nuclear factor (NF)-kappaB inhibitors [BAY11-7082 (1-10 microM) and MG132 (0.1-10 microM)] were used. SODs, CAT and GPX enzymatic activities were evaluated in cellular extract by using colorimetric enzymatic assays. Mn SODs, Cu/Zn SOD, extracellular SOD (EC SOD), CAT and GPX gene expressions were quantified by real-time and quantitative polymerase chain reaction (PCR). Mn SOD and GPX activities were dose and time-dependently increased by IL-1beta. In parallel, IL-1beta markedly enhanced Mn SOD and GPX gene expressions, but decreased Cu/Zn SOD, EC SOD and CAT gene expressions. Induction of SOD enzymatic activity and Mn SOD mRNA expression were inhibited by NF-kappaB inhibitors but not by MAPK inhibitors. IL-6 effects were similar but weaker than those of IL-1beta. In conclusion, IL-1beta, and to a lesser extend IL-6, dysregulates enzymatic antioxidant defenses in chondrocyte. These changes could lead to a transient accumulation of H(2)O(2) in mitochondria, and consequently to mitochondria damage. These changes contribute to explain the mitochondrial dysfunction observed in osteoarthritis chondrocytes.

Copper and Zinc Metallation Status of Copper Zinc Superoxide Dismutase form Amyotrophic Lateral Sclerosis Transgenic Mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lelie, H.L.; Miller, L.; Liba, A.

2010-09-24

Mutations in the metalloenzyme copper-zinc superoxide dismutase (SOD1) cause one form of familial amyotrophic lateral sclerosis (ALS), and metals are suspected to play a pivotal role in ALS pathology. To learn more about metals in ALS, we determined the metallation states of human wild-type or mutant (G37R, G93A, and H46R/H48Q) SOD1 proteins from SOD1-ALS transgenic mice spinal cords. SOD1 was gently extracted from spinal cord and separated into insoluble (aggregated) and soluble (supernatant) fractions, and then metallation states were determined by HPLC inductively coupled plasma MS. Insoluble SOD1-rich fractions were not enriched in copper and zinc. However, the soluble mutantmore » and WT SOD1s were highly metallated except for the metal-binding-region mutant H46R/H48Q, which did not bind any copper. Due to the stability conferred by high metallation of G37R and G93A, it is unlikely that these soluble SOD1s are prone to aggregation in vivo, supporting the hypothesis that immature nascent SOD1 is the substrate for aggregation. We also investigated the effect of SOD1 overexpression and disease on metal homeostasis in spinal cord cross-sections of SOD1-ALS mice using synchrotron-based x-ray fluorescence microscopy. In each mouse genotype, except for the H46R/H48Q mouse, we found a redistribution of copper between gray and white matters correlated to areas of high SOD1. Interestingly, a disease-specific increase of zinc was observed in the white matter for all mutant SOD1 mice. Together these data provide a picture of copper and zinc in the cell as well as highlight the importance of these metals in understanding SOD1-ALS pathology.« less

Zn II(atsm) is protective in amyotrophic lateral sclerosis model mice via a copper delivery mechanism.

PubMed

McAllum, Erin J; Roberts, Blaine R; Hickey, James L; Dang, Theresa N; Grubman, Alexandra; Donnelly, Paul S; Liddell, Jeffrey R; White, Anthony R; Crouch, Peter J

2015-09-01

Mutations in the metalloprotein Cu,Zn-superoxide dismutase (SOD1) cause approximately 20% of familial cases of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease for which effective therapeutics do not yet exist. Transgenic rodent models based on over-expression of mutant SOD1 have been developed and these have provided opportunity to test new therapeutic strategies and to study the mechanisms of mutant SOD1 toxicity. Although the mechanisms of mutant SOD1 toxicity are yet to be fully elucidated, incorrect or incomplete metallation of SOD1 confers abnormal folding, aggregation and biochemical properties, and improving the metallation state of SOD1 provides a viable therapeutic option. The therapeutic effects of delivering copper (Cu) to mutant SOD1 have been demonstrated recently. The aim of the current study was to determine if delivery of zinc (Zn) to SOD1 was also therapeutic. To investigate this, SOD1G37R mice were treated with the metal complex diacetyl-bis(4-methylthiosemicarbazonato)zinc(II) [Zn(II)(atsm)]. Treatment resulted in an improvement in locomotor function and survival of the mice. However, biochemical analysis of spinal cord tissue collected from the mice revealed that the treatment did not increase overall Zn levels in the spinal cord nor the Zn content of SOD1. In contrast, overall levels of Cu in the spinal cord were elevated in the Zn(II)(atsm)-treated SOD1G37R mice and the Cu content of SOD1 was also elevated. Further experiments demonstrated transmetallation of Zn(II)(atsm) in the presence of Cu to form the Cu-analogue Cu(II)(atsm), indicating that the observed therapeutic effects for Zn(II)(atsm) in SOD1G37R mice may in fact be due to in vivo transmetallation and subsequent delivery of Cu. Copyright © 2015. Published by Elsevier Inc.

Solid-state NMR studies of metal-free SOD1 fibrillar structures.

PubMed

Banci, Lucia; Blaževitš, Olga; Cantini, Francesca; Danielsson, Jens; Lang, Lisa; Luchinat, Claudio; Mao, Jiafei; Oliveberg, Mikael; Ravera, Enrico

2014-06-01

Copper-zinc superoxide dismutase 1 (SOD1) is present in the protein aggregates deposited in motor neurons of amyotrophic lateral sclerosis (ALS) patients. ALS is a neurodegenerative disease that can be either sporadic (ca. 90%) or familial (fALS). The most widely studied forms of fALS are caused by mutations in the sequence of SOD1. Ex mortuo SOD1 aggregates are usually found to be amorphous. In vitro SOD1, in its immature reduced and apo state, forms fibrillar aggregates. Previous literature data have suggested that a monomeric SOD1 construct, lacking loops IV and VII, (apoSODΔIV-VII), shares the same fibrillization properties of apoSOD1, both proteins having the common structural feature of the central β-barrel. In this work, we show that structural information can be obtained at a site-specific level from solid-state NMR. The residues that are sequentially assignable are found to be located at the putative nucleation site for fibrillar species formation in apoSOD, as detected by other experimental techniques.

Allocentric-heading recall and its relation to self-reported sense-of-direction.

PubMed

Sholl, M Jeanne; Kenny, Ryan J; DellaPorta, Katherine A

2006-05-01

A sense of direction (SOD) computes the body's facing direction relative to a reference frame grounded in the environment. The authors report on three experiments in which they used a heading-recall task to tap the functioning of a SOD system and then correlated task performance with self-reported SOD as a convergent test of the task's construct validity. On each heading-recall trial, the participant judged the photographer's allocentric heading when photographing a pictured outdoor scene. Participants were tested over the full range of SOD ratings in Experiment 1, and in Experiments 2 and 3 heading-recall at the SOD extremes was tested. In all experiments, there was wide variability in heading-recall accuracy that covaried with self-rated SOD. Parametric manipulation of various task parameters revealed some likely functional properties of the SOD system. The results support the psychological reality of a SOD system and further indicate that there are large individual differences in the efficacy with which the system functions.

High lipophilicity of meta Mn(III) N-alkylpyridylporphyrin-based SOD mimics compensates for their lower antioxidant potency and makes them equally effective as ortho analogues in protecting SOD-deficient E. coli

PubMed Central

Kos, Ivan; Benov, Ludmil; Spasojević, Ivan; Rebouças, Júlio S.; Batinić-Haberle, Ines

2009-01-01

Lipophilicity/bioavailibility of Mn(III)N-alkylpyridylporphyrin-based SOD mimics has major impact on their in vivo ability to suppress oxidative stress. Meta isomers are less potent SOD mimics than ortho analogues, but are 10-fold more lipophilic and more planar. Enhanced lipophilicity contributes to their higher accumulation in cytosol of SOD-deficient E. coli, compensating for their lower potency; consequently both isomers exert similar-to-identical protection of SOD-deficient E. coli. Thus meta isomers may be as prospective therapeutics as are ortho porphyrins. PMID:19954250

Copper/Zinc-Superoxide Dismutase Is Required for Oxytetracycline Resistance of Saccharomyces cerevisiae

PubMed Central

Avery, Simon V.; Malkapuram, Srividya; Mateus, Carolina; Babb, Kimberly S.

2000-01-01

Saccharomyces cerevisiae, along with other eukaryotes, is resistant to tetracyclines. We found that deletion of SOD1 (encoding Cu/Zn superoxide dismutase) rendered S. cerevisiae hypersensitive to oxytetracycline (OTC): a sod1Δ mutant exhibited a >95% reduction in colony-forming ability at an OTC concentration of 20 μg ml−1, whereas concentrations of up to 1,000 μg ml−1 had no effect on the growth of the wild type. OTC resistance was restored in the sod1Δ mutant by complementation with wild-type SOD1. The effect of OTC appeared to be cytotoxic and was not evident in a ctt1Δ (cytosolic catalase) mutant or in the presence of tetracycline. SOD1 transcription was not induced by OTC, suggesting that constitutive SOD1 expression is sufficient for wild-type OTC resistance. OTC uptake levels in wild-type and sod1Δ strains were similar. However, lipid peroxidation and protein oxidation were both enhanced during exposure of the sod1Δ mutant, but not the wild type, to OTC. We propose that Sod1p protects S. cerevisiae against a mode of OTC action that is dependent on oxidative damage. PMID:10613865

Single chain variable fragment antibodies block aggregation and toxicity induced by familial ALS-linked mutant forms of SOD1.

PubMed

Ghadge, Ghanashyam D; Pavlovic, John D; Koduvayur, Sujatha P; Kay, Brian K; Roos, Raymond P

2013-08-01

Approximately 10% of amyotrophic lateral sclerosis (ALS) cases are familial (known as FALS) with an autosomal dominant inheritance pattern, and ~25% of FALS cases are caused by mutations in Cu/Zn superoxide dismutase (SOD1). There is convincing evidence that mutant SOD1 (mtSOD1) kills motor neurons (MNs) because of a gain-of-function toxicity, most likely related to aggregation of mtSOD1. A number of recent reports have suggested that antibodies can be used to treat mtSOD1-induced FALS. To follow up on the use of antibodies as potential therapeutics, we generated single chain fragments of variable region antibodies (scFvs) against SOD1, and then expressed them as 'intrabodies' within a motor neuron cell line. In the present study, we describe isolation of human scFvs that interfere with mtSOD1 in vitro aggregation and toxicity. These scFvs may have therapeutic potential in sporadic ALS, as well as FALS, given that sporadic ALS may also involve abnormalities in the SOD1 protein or activity. Copyright © 2013 Elsevier Inc. All rights reserved.

Characterization of the Bacillus stearothermophilus manganese superoxide dismutase gene and its ability to complement copper/zinc superoxide dismutase deficiency in Saccharomyces cerevisiae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowler, C.; Inze, D.; Van Camp, W.

1990-03-01

Recombinant clones containing the manganese superoxide dismutase (MnSOD) gene of Bacillus stearothermophilus were isolated with an oligonucleotide probe designed to match a part of the previously determined amino acid sequence. Complementation analyses, performed by introducing each plasmid into a superoxide dismutase-deficient mutant of Escherichia coli, allowed us to define the region of DNA which encodes the MnSOD structural gene and to identify a promoter region immediately upstream from the gene. These data were subsequently confirmed by DNA sequencing. Since MnSOD is normally restricted to the mitochondria in eucaryotes, we were interested (i) in determining whether B. stearothermophilus MnSOD could functionmore » in eucaryotic cytosol and (ii) in determining whether MnSOD could replace the structurally unrelated copper/zinc superoxide dismutase (Cu/ZnSOD) which is normally found there. To test this, the sequence encoding bacterial MnSOD was cloned into a yeast expression vector and subsequently introduced into a Cu/ZnSOD-deficient mutant of the yeast Saccharomyces cerevisiae. Functional expression of the protein was demonstrated, and complementation tests revealed that the protein was able to provide tolerance at wild-type levels to conditions which are normally restrictive for this mutant. Thus, in spite of the evolutionary unrelatedness of these two enzymes, Cu/ZnSOD can be functionally replaced by MnSOD in yeast cytosol.« less

Redox Regulation of the Superoxide Dismutases SOD3 and SOD2 in the Pulmonary Circulation.

PubMed

Hernandez-Saavedra, Daniel; Swain, Kalin; Tuder, Rubin; Petersen, Steen V; Nozik-Grayck, Eva

2017-01-01

When evaluating the role of redox-regulating signaling in pulmonary vascular diseases, it is intriguing to consider the modulation of key antioxidant enzymes like superoxide dismutase (SOD) because SOD isoforms are regulated by redox reactions, and, in turn, modulate downstream redox sensitive processes. The emerging field of redox biology is built upon understanding the regulation and consequences of tightly controlled and specific reduction-oxidation reactions that are critical for diverse cellular processes including cell signaling. Of relevance, both the site of production of specific reactive oxygen and nitrogen species and the site of the antioxidant defenses are highly compartmentalized within the cell. For example, superoxide is generated during oxidative phosphorylation in the mitochondria as well as by a number of enzymatic sources within the cytosol and at the cell membrane. In the pulmonary circulation, these sources include the mitochondrial electron transport chain, NADPH oxidases (NOX1-4, Duox1,2), nitric oxide synthases, and xanthine oxidase; this important topic has been thoroughly reviewed recently [1]. In parallel with these different cellular sites of superoxide production, the three SOD isoforms are also specifically localized to the cytosol (SOD1), mitochondria (SOD2) or extracellular compartment (SOD3). This chapter focuses on the role of redox mechanisms regulating SOD2 and SOD3, with an emphasis on these processes in the setting of pulmonary hypertension.

Axonal Mitochondrial Clusters Containing Mutant SOD1 in Transgenic Models of ALS

PubMed Central

Lepanto, Paola; Elizondo, Victoria; Horjales, Sofia; Palacios, Florencia; Martinez-Palma, Laura; Marin, Monica; Beckman, Joseph S.

2009-01-01

Abstract We studied the subcellular distribution of mitochondria and superoxide dismutase-1 (SOD1) in whole mounts of microdissected motor axons of rats expressing the ALS-linked SOD1-G93A mutation. The rationale was to determine whether physical interactions between the enzyme and mitochondria were linked to the axonopathy of motor fibers occurring in amyotrophic lateral sclerosis (ALS). Mitochondria and SOD1 displayed a homogeneous distribution along motor axons both in nontransgenic rats and in those overexpressing wild-type SOD1. In contrast, axons from SOD1-G93A rats (older than 35 days) showed accumulation of mitochondria in discrete clusters located at regular intervals. Most of SOD1 immunoreactivity was enriched in these clusters and colocalized with mitochondria, suggesting a recruitment of SOD1-G93A to the organelle. The SOD1/mitochondrial clusters were abundant in motor axons but scarcely seen in sensory axons. Clusters also were stained for neuronal nitric oxide synthase, nitrotyrosine, and cytochrome c. The later also was detected surrounding clusters. Ubiquitin colocalized with clusters only at late stages of the disease. The cytoskeleton was not overtly altered in clusters. These results suggest that mutant SOD1 and defective mitochondria create localized dysfunctional domains in motor axons, which may lead to progressive axonopathy in ALS. Antioxid. Redox Signal. 11, 1535–1545. PMID:19344250

Cellular Redox Systems Impact the Aggregation of Cu,Zn Superoxide Dismutase Linked to Familial Amyotrophic Lateral Sclerosis.

PubMed

Álvarez-Zaldiernas, Cristina; Lu, Jun; Zheng, Yujuan; Yang, Hongqian; Blasi, Juan; Solsona, Carles; Holmgren, Arne

2016-08-12

Protein misfolding is implicated in neurodegenerative diseases such as ALS, where mutations of superoxide dismutase 1 (SOD1) account for about 20% of the inherited mutations. Human SOD1 (hSOD1) contains four cysteines, including Cys(57) and Cys(146), which have been linked to protein stability and folding via forming a disulfide bond, and Cys(6) and Cys(111) as free thiols. But the roles of the cellular oxidation-reduction (redox) environment in SOD1 folding and aggregation are not well understood. Here we explore the effects of cellular redox systems on the aggregation of hSOD1 proteins. We found that the known hSOD1 mutations G93A and A4V increased the capability of the thioredoxin and glutaredoxin systems to reduce hSOD1 compared with wild-type hSOD1. Treatment with inhibitors of these redox systems resulted in an increase of hSOD1 aggregates in the cytoplasm of cells transfected with mutants but not in cells transfected with wild-type hSOD1 or those containing a secondary C111G mutation. This aggregation may be coupled to changes in the redox state of the G93A and A4V mutants upon mild oxidative stress. These results strongly suggest that the thioredoxin and glutaredoxin systems are the key regulators for hSOD1 aggregation and may play critical roles in the pathogenesis of ALS. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

The Attenuation of Central Angiotensin II-dependent Pressor Response and Intra-neuronal Signaling by Intracarotid Injection of Nanoformulated Copper/Zinc Superoxide Dismutase

PubMed Central

Rosenbaugh, Erin G.; Roat, James; Gao, Lie; Yang, Rui-Fang; Manickam, Devika S.; Yin, Jing-Xiang; Schultz, Harold D.; Bronich, Tatiana K.; Batrakova, Elena V.; Kabanov, Alexander V.; Zucker, Irving H.; Zimmerman, Matthew C.

2010-01-01

Adenoviral-mediated overexpression of the intracellular superoxide (O2•−) scavenging enzyme copper/zinc superoxide dismutase (CuZnSOD) in the brain attenuates central angiotensin II (AngII)-induced cardiovascular responses. However, the therapeutic potential for adenoviral vectors is weakened by toxicity and the inability of adenoviral vectors to target the brain following peripheral administration. Therefore, we developed a non-viral delivery system in which CuZnSOD protein is electrostatically bound to a synthetic poly(ethyleneimine)-poly(ethyleneglycol) (PEI-PEG) polymer to form a polyion complex (CuZnSOD nanozyme). We hypothesized that PEI-PEG polymer increases transport of functional CuZnSOD to neurons, which inhibits AngII intra-neuronal signaling. The AngII-induced increase in O2•−, as measured by dihydroethidium fluorescence and electron paramagnetic resonance spectroscopy, was significantly inhibited in CuZnSOD nanozyme-treated neurons compared to free CuZnSOD- and non-treated neurons. CuZnSOD nanozyme also attenuated the AngII-induced inhibition of K+ current in neurons. Intracarotid injection of CuZnSOD nanozyme into rabbits significantly inhibited the pressor response of intracerebroventricular-delivered AngII; however, intracarotid injection of free CuZnSOD or PEI-PEG polymer alone failed to inhibit this response. Importantly, neither the PEI-PEG polymer alone nor the CuZnSOD nanozyme induced neuronal toxicity. These findings indicate that CuZnSOD nanozyme inhibits AngII intra-neuronal signaling in vitro and in vivo. PMID:20378166

Assessment of ligand binding at a site relevant to SOD1 oxidation and aggregation.

PubMed

Manjula, Ramu; Wright, Gareth S A; Strange, Richard W; Padmanabhan, Balasundaram

2018-05-01

Cu/Zn superoxide dismutase-1 (SOD1) mutations are causative for a subset of amyotrophic lateral sclerosis (ALS) cases. These mutations lead to structural instability, aggregation and ultimately motor neuron death. We have determined crystal structures of SOD1 in complex with a naphthalene-catechol-linked compound which binds with low micro-molar affinity to a site important for oxidative damage-induced aggregation. SOD1 Trp32 oxidation is indeed significantly inhibited by ligand binding. Our work shows how compound linking can be applied successfully to ligand interactions on the SOD1 surface to generate relatively good binding strength. The ligand, positioned in a region important for SOD1 fibrillation, offers the possibility that it, or a similar compound, could prevent the abnormal self-association that drives SOD1 toxicity in ALS. © 2018 Federation of European Biochemical Societies.

Zymographic Method for Distinguishing Different Classes of Superoxide Dismutases in Plants.

PubMed

Jamdhade, Ashwini R; Sunkar, Ramanjulu; Hivrale, Vandana K

2017-01-01

In plants, especially in chloroplasts, superoxide radical is generated when an electron is transferred to dimolecular O 2 due to decreased activity of Photosystem I. The superoxide (O 2 - ) radical accumulation is more rampant in plants exposed to abiotic stresses due to oxidation of photosystem components. Excessive superoxide radical accumulation will lead to oxidative damage to the cellular macromolecules. The ubiquitous superoxide dismutases (SODs) represent critical enzymatic antioxidant system present in cells, which can catalyze the disproportion of superoxide (O 2 - ) radical rapidly into hydrogen peroxide (H 2 O 2 ) and molecular oxygen. Depending on the metal cofactor present, the plant SODs are classified into Cu/ZnSOD, MnSOD, and FeSOD. The activity of SODs can be quantified zymographically. Additionally, using this method, different classes of SODs can be distinguished by using H 2 O 2 , KCN, and NaN 3.

Molecular Cloning and Expression of Sequence Variants of Manganese Superoxide Dismutase Genes from Wheat

USDA-ARS?s Scientific Manuscript database

Reactive oxygen species (ROS) are very harmful to living organisms due to the potential oxidation of membrane lipids, DNA, proteins, and carbohydrates. Transformed E.coli strain QC 871, superoxide dismutase (SOD) double-mutant, with three sequence variant MnSOD1, MnSOD2, and MnSOD3 manganese supero...

Metal-deficient SOD1 in amyotrophic lateral sclerosis.

PubMed

Hilton, James B; White, Anthony R; Crouch, Peter J

2015-05-01

Mutations to the ubiquitous antioxidant enzyme Cu/Zn superoxide dismutase (SOD1) were the first established genetic cause of the fatal, adult-onset neurodegenerative disease amyotrophic lateral sclerosis (ALS). It is widely accepted that these mutations do not cause ALS via a loss of antioxidant function, but elucidating the alternate toxic gain of function has proven to be elusive. Under physiological conditions, SOD1 binds one copper ion and one zinc ion per monomer to form a highly stable and functional homodimer, but there is now ample evidence to indicate aberrant persistence of SOD1 in an intermediate metal-deficient state may contribute to the protein's involvement in ALS. This review briefly discusses some of the data to support a role for metal-deficient SOD1 in the development of ALS and some of the outcomes from drug development studies that have aimed to modify the symptoms of ALS by targeting the metal state of SOD1. The implications for the metal state of SOD1 in cases of sporadic ALS that do not involve mutant SOD1 are also discussed.

A Steroidal Saponin from Ophiopogon japonicus Extends the Lifespan of Yeast via the Pathway Involved in SOD and UTH1

PubMed Central

Sun, Kaiyue; Cao, Shining; Pei, Liang; Matsuura, Akira; Xiang, Lan; Qi, Jianhua

2013-01-01

Nolinospiroside F is a steroidal saponin isolated from Ophiopogon japonicus (O. japonicus). In this study, we found that nolinospiroside F significantly extends the replicative lifespan of K6001 yeast at doses of 1, 3 and 10 μM, indicating that it has an anti-aging effect. This may be attributed to its anti-oxidative effect, as nolinospiroside F could increase yeast survival under oxidative stress conditions and decrease the level of malondialdehyde (MDA), an oxidative stress biomarker. It could also increase anti-oxidative stress genes, SOD1 and SOD2, expression, and the activity of superoxide dismutase (SOD). It increase the activity of SIRT1, an upstream inducer of SOD2 expression. In sod1 and sod2 mutant yeast strains, nolinospiroside F failed to extend their replicative lifespan. These results indicate that SOD participates in the anti-aging effect of nolinospiroside F. Furthermore, nolinospiroside F inhibited the expression of UTH1, a yeast-aging gene that is involved in the oxidative stress of yeast, and failed to extend the replicative lifespan of uth1 or skn7 mutant yeast cells. SKN7 is the transcriptional activator of UTH1. We also demonstrate that SOD and UTH1 regulate each other’s expression. Together, these results suggest that SOD and UTH1 genes are required for and play interactive roles in nolinospiroside F-mediated yeast lifespan extension. PMID:23439553

Expression and characterization of recombinant bifunctional enzymes with glutathione peroxidase and superoxide dismutase activities.

PubMed

Guan, Tuchen; Song, Jian; Wang, Yanan; Guo, Liying; Yuan, Lin; Zhao, Yingding; Gao, Yuan; Lin, Liangru; Wang, Yali; Wei, Jingyan

2017-09-01

To balance the production and decomposition of reactive oxygen species, living organisms have generated antioxidant enzymes and non-enzymatic antioxidant defense systems. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) are two important antioxidant enzymes. Apart from their catalytic functions, they protect each other, resulting in more efficient removal of reactive oxygen species, protection of cells against injury, and maintenance of the normal metabolism of reactive oxygen species. SOD catalyzes the dismutation of the superoxide anion (O 2 •- ) to oxygen (O 2 ) and hydrogen peroxide (H 2 O 2 ). H 2 O 2 is then detoxified to water by GPx. In this study, human GPx1 Ser and the Alvinella pompejana SOD (ApSOD) gene were used to design and generate several recombinant proteins with both GPx and SOD activities by combining traditional fusion protein technology, a cysteine auxotrophic expression system, and a single protein production (SPP) system. Among the fusion proteins, Se-hGPx1 Ser -L-ApSOD exhibited the highest SOD and GPx activities. Additional research was conducted to better understand the properties of Se-hGPx1 Ser -L-ApSOD. The synergism of Se-hGPx1 Ser -L-ApSOD was evaluated by using an in vitro model. This research may facilitate future studies on the cooperation and catalytic mechanisms of GPx and SOD. We believe that the bifunctional enzyme has potential applications as a potent antioxidant. Copyright © 2017 Elsevier Inc. All rights reserved.

Neutropenia restores virulence to an attenuated Cu,Zn superoxide dismutase-deficient Haemophilus ducreyi strain in the swine model of chancroid.

PubMed

San Mateo, L R; Toffer, K L; Orndorff, P E; Kawula, T H

1999-10-01

Haemophilus ducreyi causes chancroid, a sexually transmitted cutaneous genital ulcer disease associated with increased heterosexual transmission of human immunodeficiency virus. H. ducreyi expresses a periplasmic copper-zinc superoxide dismutase (Cu, Zn SOD) that protects the bacterium from killing by exogenous superoxide in vitro. We hypothesized that the Cu,Zn SOD would protect H. ducreyi from immune cell killing, enhance survival, and affect ulcer development in vivo. In order to test this hypothesis and study the role of the Cu,Zn SOD in H. ducreyi pathogenesis, we compared a Cu,Zn SOD-deficient H. ducreyi strain to its isogenic wild-type parent with respect to survival and ulcer development in immunocompetent and immunosuppressed pigs. The Cu,Zn SOD-deficient strain was recovered from significantly fewer inoculated sites and in significantly lower numbers than the wild-type parent strain or a merodiploid (sodC+ sodC) strain after infection of immunocompetent pigs. In contrast, survival of the wild-type and Cu,Zn SOD-deficient strains was not significantly different in pigs that were rendered neutropenic by treatment with cyclophosphamide. Ulcer severity in pigs was not significantly different between sites inoculated with wild type and sites inoculated with Cu,Zn SOD-deficient H. ducreyi. Our data suggest that the periplasmic Cu,Zn SOD is an important virulence determinant in H. ducreyi, protecting the bacterium from host immune cell killing and contributing to survival and persistence in the host.

Neutropenia Restores Virulence to an Attenuated Cu,Zn Superoxide Dismutase-Deficient Haemophilus ducreyi Strain in the Swine Model of Chancroid

PubMed Central

San Mateo, Lani R.; Toffer, Kristen L.; Orndorff, Paul E.; Kawula, Thomas H.

1999-01-01

Haemophilus ducreyi causes chancroid, a sexually transmitted cutaneous genital ulcer disease associated with increased heterosexual transmission of human immunodeficiency virus. H. ducreyi expresses a periplasmic copper-zinc superoxide dismutase (Cu,Zn SOD) that protects the bacterium from killing by exogenous superoxide in vitro. We hypothesized that the Cu,Zn SOD would protect H. ducreyi from immune cell killing, enhance survival, and affect ulcer development in vivo. In order to test this hypothesis and study the role of the Cu,Zn SOD in H. ducreyi pathogenesis, we compared a Cu,Zn SOD-deficient H. ducreyi strain to its isogenic wild-type parent with respect to survival and ulcer development in immunocompetent and immunosuppressed pigs. The Cu,Zn SOD-deficient strain was recovered from significantly fewer inoculated sites and in significantly lower numbers than the wild-type parent strain or a merodiploid (sodC+ sodC) strain after infection of immunocompetent pigs. In contrast, survival of the wild-type and Cu,Zn SOD-deficient strains was not significantly different in pigs that were rendered neutropenic by treatment with cyclophosphamide. Ulcer severity in pigs was not significantly different between sites inoculated with wild type and sites inoculated with Cu,Zn SOD-deficient H. ducreyi. Our data suggest that the periplasmic Cu,Zn SOD is an important virulence determinant in H. ducreyi, protecting the bacterium from host immune cell killing and contributing to survival and persistence in the host. PMID:10496915

Enhanced Skeletal Muscle Expression of EcSOD Mitigates Streptozotocin-Induced Diabetic Cardiomyopathy by Reducing Oxidative Stress and Aberrant Cell Signaling

PubMed Central

Call, Jarrod A.; Chain, Kristopher H.; Martin, Kyle S.; Lira, Vitor A.; Okutsu, Mitsuharu; Zhang, Mei; Yan, Zhen

2015-01-01

Background Exercise training enhances extracellular superoxide dismutase (EcSOD) expression in skeletal muscle and elicits positive health outcomes in individuals with diabetes. The goal of this study was to determine if enhanced skeletal muscle expression of EcSOD is sufficient to mitigate streptozotocin (STZ)-induced diabetic cardiomyopathy (DCM). Methods and Results Exercise training promotes EcSOD expression in skeletal muscle and provides protection against DCM; however, it is not known if enhanced EcSOD expression in skeletal muscle plays a functional role in this protection. Here, we show that skeletal muscle-specific EcSOD transgenic mice (TG) are protected from cardiac hypertrophy, fibrosis and dysfunction under the condition of type-1 diabetes induced by STZ injection. We also show that both exercise training and muscle-specific transgenic expression of EcSOD result in elevated EcSOD protein in the blood and heart without increased transcription in the heart, suggesting enhanced expression of EcSOD from skeletal muscle redistributes to the heart. Importantly, cardiac tissue in TG mice displayed significantly reduced oxidative stress, aberrant cell signaling and inflammatory cytokine expression compared with wild type mice under the same diabetic condition. Conclusions Enhanced expression of EcSOD in skeletal muscle is sufficient to mitigate STZ-induced DCM through attenuation of oxidative stress, aberrant cell signaling and inflammation, suggesting a cross-organ mechanism by which exercise training improves cardiac function in diabetes. PMID:25504759

Immunogenicity and protective efficacy of recombinant iron superoxide dismutase protein from Bordetella pertussis in mice models.

PubMed

Yılmaz, Çiğdem; Apak, Aycan; Özcengiz, Erkan; Özcengiz, Gülay

2016-11-01

Whooping cough (pertussis) is a highly contagious respiratory infection caused by Bordetella pertussis. Although availability of effective pertussis vaccines reportedly decreases the incidence of the disease, B. pertussis circulation in populations has not been eliminated. Thus, it is necessary to find new protein candidates with greater immune protective capacities than the currently available acellular pertussis vaccines. In this study, iron superoxide dismutase (FeSOD) gene (sodB) was cloned, expressed in Escherichia coli and recombinant FeSOD protein thence purified. The recombinant protein (rFeSOD) was formulated with aluminum hydroxide (Alum) or monophosphoryl lipid A (MPLA) and injected intraperitoneally to immunize mice, after which IgG1, IgG2a and IFN-γ titers were measured to assess humoral and cellular responses, respectively, to these immunizations. The extent of bacterial colonization in lungs of intranasally challenged mice was determined 5, 8 and 14 days post-challenge. IgG1 and IgG2a responses were significantly stronger in mice that had been immunized with rFeSOD-MPLA than in those that had received rFeSOD-Alum (P < 0.05). Additionally, IgG2a titers were higher in mice vaccinated with recombinant protein FeSOD (rFeSOD) formulated with MPLA, especially after the second immunization. Immunization with rFeSOD-MPLA also provided a modest, but significant decrease in bacterial counts in lungs of mice (P < 0.05). Antigen specific-IFN-γ responses were significantly stronger in the group vaccinated with rFeSOD-MPLA, which could account for the lower bacterial counts. These findings suggest that rFeSOD protein formulated with MPLA has potential as an acellular pertussis vaccine candidate component. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

Acute Pre-/Post-Treatment with 8th Day SOD-Like Supreme (a Free Radical Scavenging Health Product) Protects against Oxidant-Induced Injury in Cultured Cardiomyocytes and Hepatocytes In Vitro as Well as in Mouse Myocardium and Liver In Vivo.

PubMed

Leong, Pou Kuan; Chen, Jihang; Chan, Wing Man; Leung, Hoi Yan; Chan, Lincoln; Ko, Kam Ming

2017-04-10

8th Day superoxide dismutase (SOD)-Like Supreme (SOD-Like Supreme, a free radical scavenging health product) is an antioxidant-enriched fermentation preparation with free radical scavenging properties. In the present study, the cellular/tissue protective actions of SOD-Like Supreme against menadione toxicity in cultured H9c2 cardiomyocytes and in AML12 hepatocytes as well as oxidant-induced injury in the mouse myocardium and liver were investigated. SOD-Like Supreme was found to possess potent free radical scavenging activity in vitro as assessed by an oxygen radical absorbance capacity assay. Incubation with SOD-Like Supreme (0.5-3% (v/v)) was shown to protect against menadione-induced toxicity in H9c2 and AML12 cells, as evidenced by increases in cell viability. The ability of SOD-Like Supreme to protect against menadione cytotoxicity was associated with an elevation in the cellular reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio in menadione-challenged cells. Consistent with the cell-based studies, pre-/post-treatment with SOD-Like Supreme (0.69 and 2.06 mL/kg, three intermittent doses per day for two consecutive days) was found to protect against isoproterenol-induced myocardial injury and carbon tetrachloride hepatotoxicity in mice. The cardio/hepatoprotection afforded by SOD-Like Supreme was also paralleled by increases in myocardial/hepatic mitochondrial GSH/GSSG ratios in the SOD-Like Supreme-treated/oxidant-challenged mice. In conclusion, incubation/treatment with SOD-Like Supreme was found to protect against oxidant-induced injury in vitro and in vivo, presumably by virtue of its free radical scavenging activity.

Canine Degenerative Myelopathy: Biochemical characterization of superoxide dismutase 1 in the first naturally occurring non-human amyotrophic lateral sclerosis model1

PubMed Central

Crisp, Matthew J.; Beckett, Jeffrey; Coates, Joan R.; Miller, Timothy M.

2013-01-01

Mutations in canine superoxide dismutase 1 (SOD1) have recently been shown to cause canine degenerative myelopathy, a disabling neurodegenerative disorder affecting specific breeds of dogs characterized by progressive motor neuron loss and paralysis until death, or more common, euthanasia. This discovery makes canine degenerative myelopathy the first and only naturally occurring non-human model of amyotrophic lateral sclerosis (ALS), closely paralleling the clinical, pathological, and genetic presentation of its human counterpart, SOD1-mediated familial ALS. To further understand the biochemical role that canine SOD1 plays in this disease and how it may be similar to human SOD1, we characterized the only two SOD1 mutations described in affected dogs to date, E40K and T18S. We show that a detergent-insoluble species of mutant SOD1 is present in spinal cords of affected dogs that increases with disease progression. Our in vitro results indicate that both canine SOD1 mutants form enzymatically active dimers, arguing against a loss of function in affected homozygous animals. Further studies show that these mutants, like most human SOD1 mutants, have an increased propensity to form aggregates in cell culture, with 10-20% of cells possessing visible aggregates. Creation of the E40K mutation in human SOD1 recapitulates the normal enzymatic activity but not the aggregation propensity seen with the canine mutant. Our findings lend strong biochemical support to the toxic role of SOD1 in canine degenerative myelopathy and establish close parallels for the role mutant SOD1 plays in both canine and human disorders. PMID:23707216

Canine degenerative myelopathy: biochemical characterization of superoxide dismutase 1 in the first naturally occurring non-human amyotrophic lateral sclerosis model.

PubMed

Crisp, Matthew J; Beckett, Jeffrey; Coates, Joan R; Miller, Timothy M

2013-10-01

Mutations in canine superoxide dismutase 1 (SOD1) have recently been shown to cause canine degenerative myelopathy, a disabling neurodegenerative disorder affecting specific breeds of dogs characterized by progressive motor neuron loss and paralysis until death, or more common, euthanasia. This discovery makes canine degenerative myelopathy the first and only naturally occurring non-human model of amyotrophic lateral sclerosis (ALS), closely paralleling the clinical, pathological, and genetic presentation of its human counterpart, SOD1-mediated familial ALS. To further understand the biochemical role that canine SOD1 plays in this disease and how it may be similar to human SOD1, we characterized the only two SOD1 mutations described in affected dogs to date, E40K and T18S. We show that a detergent-insoluble species of mutant SOD1 is present in spinal cords of affected dogs that increases with disease progression. Our in vitro results indicate that both canine SOD1 mutants form enzymatically active dimers, arguing against a loss of function in affected homozygous animals. Further studies show that these mutants, like most human SOD1 mutants, have an increased propensity to form aggregates in cell culture, with 10-20% of cells possessing visible aggregates. Creation of the E40K mutation in human SOD1 recapitulates the normal enzymatic activity but not the aggregation propensity seen with the canine mutant. Our findings lend strong biochemical support to the toxic role of SOD1 in canine degenerative myelopathy and establish close parallels for the role mutant SOD1 plays in both canine and human disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

Kaplan-Meier Meets Chemical Kinetics: Intrinsic Rate of SOD1 Amyloidogenesis Decreased by Subset of ALS Mutations and Cannot Fully Explain Age of Disease Onset.

PubMed

Abdolvahabi, Alireza; Shi, Yunhua; Rasouli, Sanaz; Croom, Corbin M; Aliyan, Amir; Martí, Angel A; Shaw, Bryan F

2017-06-21

Over 150 mutations in SOD1 (superoxide dismutase-1) cause amyotrophic lateral sclerosis (ALS), presumably by accelerating SOD1 amyloidogenesis. Like many nucleation processes, SOD1 fibrillization is stochastic (in vitro), which inhibits the determination of aggregation rates (and obscures whether rates correlate with patient phenotypes). Here, we diverged from classical chemical kinetics and used Kaplan-Meier estimators to quantify the probability of apo-SOD1 fibrillization (in vitro) from ∼10 3 replicate amyloid assays of wild-type (WT) SOD1 and nine ALS variants. The probability of apo-SOD1 fibrillization (expressed as a Hazard ratio) is increased by certain ALS-linked SOD1 mutations but is decreased or remains unchanged by other mutations. Despite this diversity, Hazard ratios of fibrillization correlated linearly with (and for three mutants, approximately equaled) Hazard ratios of patient survival (R 2 = 0.67; Pearson's r = 0.82). No correlation exists between Hazard ratios of fibrillization and age of initial onset of ALS (R 2 = 0.09). Thus, Hazard ratios of fibrillization might explain rates of disease progression but not onset. Classical kinetic metrics of fibrillization, i.e., mean lag time and propagation rate, did not correlate as strongly with phenotype (and ALS mutations did not uniformly accelerate mean rate of nucleation or propagation). A strong correlation was found, however, between mean ThT fluorescence at lag time and patient survival (R 2 = 0.93); oligomers of SOD1 with weaker fluorescence correlated with shorter survival. This study suggests that SOD1 mutations trigger ALS by altering a property of SOD1 or its oligomers other than the intrinsic rate of amyloid nucleation (e.g., oligomer stability; rates of intercellular propagation; affinity for membrane surfaces; and maturation rate).

Myocardial protective effect of extracellular superoxide dismutase gene modified bone marrow mesenchymal stromal cells on infarcted mice hearts.

PubMed

Pan, Qiao; Qin, Xing; Ma, Sai; Wang, Haichang; Cheng, Kang; Song, Xinxing; Gao, Haokao; Wang, Qiang; Tao, Rannie; Wang, Yabin; Li, Xiujuan; Xiong, Lize; Cao, Feng

2014-01-01

Extracellular superoxide dismutase (ecSOD) is a unique scavenger of superoxide anions and a promising target of gene therapy for ischemia/reperfusion injury (I/R). However, conventional gene therapies have limitation in effectiveness and efficiency. This study aimed to investigate the protective effects of ecSOD gene modified bone marrow mesenchymal stromal cells (BMSCs) on cardiac function improvement in mice infarcted heart. BMSCs were isolated from Fluc(+) transgenic mice (Tg FVB[Fluc(+)]) and transfected by adenovirus combined with human ecSOD gene. ELISA was performed to determine ecSOD protein level. Female syngeneic FVB mice were randomized into 5 groups: (1) Sham group (sham); (2) MI group (MI); (3) MI+BMSCs group (BMSC); (4) MI+BMSCs-vector group (BMSC-vector); (5) MI+ BMSCs-ecSOD group (BMSC-ecSOD). MI was accomplished by ligation of the left anterior descending artery. BMSCs (2 x 10(6)) were injected into the border zone of infarction. In vivo bioluminescence imaging (BLI) was performed to monitor transplanted BMSCs viability. Echocardiography and histological staining revealed that BMSCs-ecSOD significantly reduced myocardial infarction size and improved cardiac function. Lucigenin chemiluminescence, DHE and TUNEL staining demonstrated that BMSCs-ecSOD delivery reduced ROS level and cell apoptosis both in vivo and in vitro. Western blot assay revealed that ecSOD supplementation increased FoxO3a phosphorylation in cardiomyocytes. Moreover, quantitative real-time PCR showed that pro-apoptotic factors (bim and bax) were decreased while the anti-apoptotic factor mir-21 expression was increased after ecSOD intervention. Intra-myocardial transplantation of adenovirus-ecSOD transfected BMSCs could exert potential cardiac protection against MI, which may be partly through reduction of oxidative stress and improvement of BMSCs survival.

Manganese superoxide dismutase: beyond life and death

PubMed Central

Holley, Aaron K.; Dhar, Sanjit Kumar; Xu, Yong

2010-01-01

Manganese superoxide dismutase (MnSOD) is a nuclear-encoded antioxidant enzyme that localizes to the mitochondria. Expression of MnSOD is essential for the survival of aerobic life. Transgenic mice expressing a luciferase reporter gene under the control of the human MnSOD promoter demonstrate that the level of MnSOD is reduced prior to the formation of cancer. Overexpression of MnSOD in transgenic mice reduces the incidences and multiplicity of papillomas in a DMBA/TPA skin carcinogenesis model. However, MnSOD deficiency does not lead to enhanced tumorigenicity of skin tissue similarly treated because MnSOD can modulate both the p53-mediated apoptosis and AP-1-mediated cell proliferation pathways. Apoptosis is associated with an increase in mitochondrial levels of p53 suggesting a link between MnSOD deficiency and mitochondrial-mediated apoptosis. Activation of p53 is preventable by application of a SOD mimetic (MnTE-2-PyP5+). Thus, p53 translocation to mitochondria and subsequent inactivation of MnSOD explain the observed mitochondrial dysfunction that leads to transcription-dependent mechanisms of p53-induced apoptosis. Administration of MnTE-2-PyP5+ following apoptosis but prior to proliferation leads to suppression of protein carbonyls and reduces the activity of AP-1 and the level of the proliferating cellular nuclear antigen, without reducing the activity of p53 or DNA fragmentation following TPA treatment. Remarkably, the incidence and multiplicity of skin tumors are drastically reduced in mice that receive MnTE-2-PyP5+ prior to cell proliferation. The results demonstrate the role of MnSOD beyond its essential role for survival and suggest a novel strategy for an antioxidant approach to cancer intervention. PMID:20454814

Histone Acetylation Regulates the Cell-Specific and Interferon-γ–Inducible Expression of Extracellular Superoxide Dismutase in Human Pulmonary Arteries

PubMed Central

Stepp, Marcus W.; Vorst, Alan L.; Folz, Rodney J.

2011-01-01

Extracellular superoxide dismutase (EC-SOD) is the major antioxidant enzyme present in the vascular wall, and is responsible for both the protection of vessels from oxidative stress and for the modulation of vascular tone. Concentrations of EC-SOD in human pulmonary arteries are very high relative to other tissues, and the expression of EC-SOD appears highly restricted to smooth muscle. The molecular basis for this smooth muscle–specific expression of EC-SOD is not known. Here we assessed the role of epigenetic factors in regulating the cell-specific and IFN-γ–inducible expression of EC-SOD in human pulmonary artery cells. The analysis of CpG site methylation within the promoter and coding regions of the EC-SOD gene demonstrated higher levels of DNA methylation within the distal promoter region in endothelial cells compared with smooth muscle cells. Exposure of both cell types to DNA demethylation agents reactivated the transcription of EC-SOD in endothelial cells alone. However, exposure to the histone deacetylase inhibitor trichostatin A (TSA) significantly induced EC-SOD gene expression in both endothelial cells and smooth muscle cells. Concentrations of EC-SOD mRNA were also induced up to 45-fold by IFN-γ in smooth muscle cells, but not in endothelial cells. The IFN-γ–dependent expression of EC-SOD was regulated by the Janus tyrosine kinase/signal transducers and activators of transcription proteins signaling pathway. Simultaneous exposure to TSA and IFN-γ produced a synergistic effect on the induction of EC-SOD gene expression, but only in endothelial cells. These findings provide strong evidence that EC-SOD cell-specific and IFN-γ–inducible expression in pulmonary artery cells is regulated, to a major degree, by epigenetic mechanisms that include histone acetylation and DNA methylation. PMID:21493784

Differences in glutathione S-transferase pi expression in transgenic mice with symptoms of neurodegeneration.

PubMed

Kaźmierczak, Beata; Kuźma-Kozakiewicz, Magdalena; Usarek, Ewa; Barańczyk-Kuźma, Anna

2011-01-01

Glutathione S-transferase pi (GST pi) is an enzyme involved in cell protection against toxic electrophiles and products of oxidative stress. GST pi expression was studied in transgenic mice hybrids (B6-C3H) with symptoms of neurodegeneration harboring SOD1G93A (SOD1/+), Dync1h1 (Cra1/+) and double (Cra1/SOD1) mutations, at presymptomatic and symptomatic stages (age 70, 140, 365 days) using RT-PCR and Western blotting. The main changes in GST pi expression were observed in mice with the SODG93A mutation. In SOD1/+ and Cra1/SOD1 transgenics, with the exception of cerebellum, the changes in GST pi-mRNA accompanied those in GST pi protein. In brain cortex of both groups the expression was unchanged at the presymptomatic (age 70 days) but was lower at the symptomatic stage (age 140 days) and at both stages in hippocampus and spinal cord of SOD1/+ but not of Cra1/SOD1 mice compared to age-matched wild-type controls. In cerebellum of the presymptomatic and the symptomatic SOD1/+ mice and presymptomatic Cra1/SOD1 mice, the GST pi-mRNA was drastically elevated but the protein level remained unchanged. In Cra1/+ transgenics there were no changes in GST pi expression in any CNS region both on the mRNA and on the protein level. It can be concluded that the SOD1G93A but not the Dync1h1 mutation significantly decreases detoxification efficiency of GST pi in CNS, however the Dync1h1 mutation reduces the effects caused by the SOD1G93A mutation. Despite similarities in neurological symptoms, the differences in GST pi expression between SOD1/+ and Cra1/+ transgenics indicate a distinct pathogenic entity of these two conditions.

Clinical Relevance of Multiple Single-Nucleotide Polymorphisms in Pneumocystis jirovecii Pneumonia: Development of a Multiplex PCR-Single-Base-Extension Methodology▿

PubMed Central

Esteves, F.; Gaspar, J.; De Sousa, B.; Antunes, F.; Mansinho, K.; Matos, O.

2011-01-01

Pneumocystis jirovecii pneumonia (PcP) is a major cause of respiratory illness in patients with AIDS. The identification of multiple single-nucleotide polymorphisms (SNPs) at three distinct P. jirovecii loci encoding dihydrofolate reductase (DHFR), mitochondrial large-subunit rRNA (mtLSU rRNA), and superoxide dismutase (SOD) was achieved using multiplex-PCR (MPCR) followed by direct sequencing and two single-base extension (SBE) techniques. Four SNPs (DHFR312, mt85, SOD215, and SOD110), correlated previously with parameters of disease, were amplified and genotyped simultaneously. The concordance of results between the standard sequencing technique (direct sequencing) and SBE analysis was 96.9% for the acrylamide gel electrophoresis and 98.4% for the capillary electrophoresis. The cross-genetic analysis established several statistical associations among the SNPs studied: mt85C-SOD110T, SOD110T-SOD215C, and SOD110C-SOD215T. These results were confirmed by cluster analysis. Data showed that among the isolates with low to moderate parasite burden, the highest percentages of DHFR312C, mt85C, SOD110T, and SOD215C were detected, whereas for high parasite burden cases the highest frequencies were observed among isolates with DHFR312T, mt85T, SOD110C, and SOD215T. The polymorphisms studied were shown to be suitable genetic targets potentially correlated with PcP clinical data that can be used as predictors of outcome in further studies to help clinical decision-making in the management of PcP. The MPCR/SBE protocol described for the first time in the present study was shown to be a rapid, highly accurate method for genotyping P. jirovecii SNPs encoded by different loci that could be used for epidemiological studies and as an additional procedure for the prognostic classification and diagnosis of PcP. PMID:21389160

Clinical relevance of multiple single-nucleotide polymorphisms in Pneumocystis jirovecii Pneumonia: development of a multiplex PCR-single-base-extension methodology.

PubMed

Esteves, F; Gaspar, J; De Sousa, B; Antunes, F; Mansinho, K; Matos, O

2011-05-01

Pneumocystis jirovecii pneumonia (PcP) is a major cause of respiratory illness in patients with AIDS. The identification of multiple single-nucleotide polymorphisms (SNPs) at three distinct P. jirovecii loci encoding dihydrofolate reductase (DHFR), mitochondrial large-subunit rRNA (mtLSU rRNA), and superoxide dismutase (SOD) was achieved using multiplex-PCR (MPCR) followed by direct sequencing and two single-base extension (SBE) techniques. Four SNPs (DHFR312, mt85, SOD215, and SOD110), correlated previously with parameters of disease, were amplified and genotyped simultaneously. The concordance of results between the standard sequencing technique (direct sequencing) and SBE analysis was 96.9% for the acrylamide gel electrophoresis and 98.4% for the capillary electrophoresis. The cross-genetic analysis established several statistical associations among the SNPs studied: mt85C-SOD110T, SOD110T-SOD215C, and SOD110C-SOD215T. These results were confirmed by cluster analysis. Data showed that among the isolates with low to moderate parasite burden, the highest percentages of DHFR312C, mt85C, SOD110T, and SOD215C were detected, whereas for high parasite burden cases the highest frequencies were observed among isolates with DHFR312T, mt85T, SOD110C, and SOD215T. The polymorphisms studied were shown to be suitable genetic targets potentially correlated with PcP clinical data that can be used as predictors of outcome in further studies to help clinical decision-making in the management of PcP. The MPCR/SBE protocol described for the first time in the present study was shown to be a rapid, highly accurate method for genotyping P. jirovecii SNPs encoded by different loci that could be used for epidemiological studies and as an additional procedure for the prognostic classification and diagnosis of PcP.

Copper Transporter ATP7A Protects Against Endothelial Dysfunction in Type 1 Diabetic Mice by Regulating Extracellular Superoxide Dismutase

PubMed Central

Sudhahar, Varadarajan; Urao, Norifumi; Oshikawa, Jin; McKinney, Ronald D.; Llanos, Roxana M.; Mercer, Julian F.B.; Ushio-Fukai, Masuko; Fukai, Tohru

2013-01-01

Oxidative stress and endothelial dysfunction contribute to vascular complication in diabetes. Extracellular superoxide dismutase (SOD3) is one of the key antioxidant enzymes that obtains copper via copper transporter ATP7A. SOD3 is secreted from vascular smooth muscles cells (VSMCs) and anchors at the endothelial surface. The role of SOD3 and ATP7A in endothelial dysfunction in type 1 diabetes mellitus (T1DM) is entirely unknown. Here we show that the specific activity of SOD3, but not SOD1, is decreased, which is associated with increased O2•− production in aortas of streptozotocin-induced and genetically induced Ins2Akita T1DM mice. Exogenous copper partially rescued SOD3 activity in isolated T1DM vessels. Functionally, acetylcholine-induced, endothelium-dependent relaxation is impaired in T1DM mesenteric arteries, which is rescued by SOD mimetic tempol or gene transfer of SOD3. Mechanistically, ATP7A expression in T1DM vessels is dramatically decreased whereas other copper transport proteins are not altered. T1DM-induced endothelial dysfunction and decrease of SOD3 activity are rescued in transgenic mice overexpressing ATP7A. Furthermore, SOD3-deficient T1DM mice or ATP7A mutant T1DM mice augment endothelial dysfunction and vascular O2•− production versus T1DM mice. These effects are in part due to hypoinsulinemia in T1DM mice, since insulin treatment, but not high glucose, increases ATP7A expression in VSMCs and restores SOD3 activity in the organoid culture of T1DM vessels. In summary, a decrease in ATP7A protein expression contributes to impaired SOD3 activity, resulting in O2•− overproduction and endothelial dysfunction in blood vessels of T1DM. Thus, restoring copper transporter function is an essential therapeutic approach for oxidant stress–dependent vascular and metabolic diseases. PMID:23884884

Localization of superoxide dismutases and hydrogen peroxide in legume root nodules.

PubMed

Rubio, Maria C; James, Euan K; Clemente, Maria R; Bucciarelli, Bruna; Fedorova, Maria; Vance, Carroll P; Becana, Manuel

2004-12-01

Superoxide dismutases (SODs) catalyze the dismutation of superoxide radicals to O2 and H2O2 and thus represent a primary line of antioxidant defense in all aerobic organisms. H2O2 is a signal molecule involved in the plant's response to pathogen attack and other stress conditions as well as in nodulation. In this work, we have tested the hypothesis that SODs are a source of H2O2 in indeterminate alfalfa (Medicago sativa) and pea (Pisum sativum) nodules. The transcripts and proteins of the major SODs of nodules were localized by in situ RNA hybridization and immunogold electron microscopy, respectively, whereas H2O2 was localized cytochemically by electron microscopy of cerium-perfused nodule tissue. The transcript and protein of cytosolic CuZnSOD are most abundant in the meristem (I) and invasion (II) zones, interzone II-III, and distal part of the N2-fixing zone (III), and those of MnSOD in zone III, especially in the infected cells. At the subcellular level, CuZnSOD was found in the infection threads, cytosol adjacent to cell walls, and apoplast, whereas MnSOD was in the bacteroids, bacteria within infection threads, and mitochondria. The distinct expression pattern of CuZnSOD and MnSOD suggests specific roles of the enzymes in nodules. Large amounts of H2O2 were found at the same three nodule sites as CuZnSOD but not in association with MnSOD. This colocalization led us to postulate that cytosolic CuZnSOD is a source of H2O2 in nodules. Furthermore, the absence or large reduction of H2O2 in nodule tissue preincubated with enzyme inhibitors (cyanide, azide, diphenyleneiodonium, diethyldithiocarbamate) provides strong support to the hypothesis that at least some of the H2O2 originates by the sequential operation of an NADPH oxidase-like enzyme and CuZnSOD. Results also show that there is abundant H2O2 associated with degrading bacteroids in the senescent zone (IV), which reflects the oxidative stress ensued during nodule senescence.

Antioxidant enzyme expression and reactive oxygen species damage in prostatic intraepithelial neoplasia and cancer.

PubMed

Bostwick, D G; Alexander, E E; Singh, R; Shan, A; Qian, J; Santella, R M; Oberley, L W; Yan, T; Zhong, W; Jiang, X; Oberley, T D

2000-07-01

Oxidative stress results in damage to cellular structures and has been linked to many diseases, including cancer. The authors sought to determine whether the expression of three major antioxidant enzymes, copper-zinc superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), and catalase, was altered in human prostate carcinoma and its likely precursor, high grade prostatic intraepithelial neoplasia (PIN). The level of reactive oxygen species damage was evaluated by measuring the expression of the DNA adduct 8-hydroxydeoxyguanosine. The authors evaluated the tissue expression of the antioxidant enzymes in prostate carcinoma by immunohistochemistry, immunogold electron microscopy, and enzymatic assay. The polymerase chain reaction was used to amplify and screen tissue specimens for the genes of SOD1, SOD2, and extracellular SOD (SOD3). Matched paraffin embedded tissue sections were evaluated by RNA in situ hybridization for expression of SOD1 and immunohistochemically for the DNA adduct 8-hydroxydeoxyguanosine. All prostatic tissues, including cancer, displayed immunoreactivity for the three antioxidant enzymes in epithelial cells, with no staining of the stroma, inflammatory cells, or endothelial cells. The number of immunoreactive cells was greater in benign epithelium than in PIN and cancer for each enzyme. The mean percentage and intensity of immunoreactive cells was greatest for SOD2, intermediate for SOD1, and lower for catalase. Staining in cancer was heterogeneous. Immunogold ultrasound studies revealed strong mitochondrial labeling for SOD2, which was greater in benign epithelium than in cancer; SOD1 labeling was invariably weaker, with nuclear labeling in benign epithelium and cytoplasmic labeling in cancer cells. There was no difference in enzyme activity for the three antioxidant enzymes between benign epithelium and cancer. No mutations were found in the 5 exons of SOD1, 5 exons of SOD2, and 3 exons of SOD3, except for 3 of 20 cases with polymorphisms for exon 3 of SOD1. Intense nuclear immunoreactivity for 8-hydroxydeoxyguanosine was present in fewer than 3% of epithelial cells, with no apparent differences among benign epithelium, PIN, and cancer. SOD1, SOD2, and catalase had lower expression in PIN and prostate carcinoma than in benign epithelium. The number of immunoreactive cells in PIN was similar to cancer, indicating that these are closely related. Enzyme activities were variable, with no difference between benign epithelial cells and cancer, although this lack of change in enzyme activity could have been due to the presence of contaminating benign cells within the cancer specimens. The results of reactive oxygen species damage were found only in the epithelium and not in the stroma. Expression of the DNA adduct 8-hydroxydeoxyguanosine was present in fewer than 3% of cells, with no apparent differences among benign epithelium, PIN, and cancer. These findings suggest that oxidative stress is an early event in carcinogenesis. Copyright 2000 American Cancer Society.

Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus.

PubMed

Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

2009-10-30

The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.

Is SOD1 loss of function involved in amyotrophic lateral sclerosis?

PubMed Central

Saccon, Rachele A.; Bunton-Stasyshyn, Rosie K. A.; Fisher, Elizabeth M.C.; Fratta, Pietro

2013-01-01

Mutations in the gene superoxide dismutase 1 (SOD1) are causative for familial forms of the neurodegenerative disease amyotrophic lateral sclerosis. When the first SOD1 mutations were identified they were postulated to give rise to amyotrophic lateral sclerosis through a loss of function mechanism, but experimental data soon showed that the disease arises from a—still unknown—toxic gain of function, and the possibility that loss of function plays a role in amyotrophic lateral sclerosis pathogenesis was abandoned. Although loss of function is not causative for amyotrophic lateral sclerosis, here we re-examine two decades of evidence regarding whether loss of function may play a modifying role in SOD1–amyotrophic lateral sclerosis. From analysing published data from patients with SOD1–amyotrophic lateral sclerosis, we find a marked loss of SOD1 enzyme activity arising from almost all mutations. We continue to examine functional data from all Sod1 knockout mice and we find obvious detrimental effects within the nervous system with, interestingly, some specificity for the motor system. Here, we bring together historical and recent experimental findings to conclude that there is a possibility that SOD1 loss of function may play a modifying role in amyotrophic lateral sclerosis. This likelihood has implications for some current therapies aimed at knocking down the level of mutant protein in patients with SOD1–amyotrophic lateral sclerosis. Finally, the wide-ranging phenotypes that result from loss of function indicate that SOD1 gene sequences should be screened in diseases other than amyotrophic lateral sclerosis. PMID:23687121

A semisynthetic strategy leads to alteration of the backbone amidate ligand in the NiSOD active site

DOE PAGES

Campeciño, Julius O.; Dudycz, Lech W.; Tumelty, David; ...

2015-07-01

Computational investigations have implicated the amidate ligand in nickel superoxide dismutase (NiSOD) in stabilizing Ni-centered redox catalysis and in preventing cysteine thiolate ligand oxidation. To test these predictions, we have used an experimental approach utilizing a semisynthetic scheme that employs native chemical ligation of a pentapeptide (HCDLP) to recombinant S. coelicolor NiSOD lacking these N-terminal residues, NΔ5-NiSOD. Wild-type enzyme produced in this manner exhibits the characteristic spectral properties of recombinant WT-NiSOD and is as catalytically active. The semisynthetic scheme was also employed to construct a variant where the amidate ligand was converted to a secondary amine, H1*-NiSOD, a novel strategymore » that retains a backbone N-donor atom. The H1*-NiSOD variant was found to have only ~1% of the catalytic activity of the recombinant wild-type enzyme, and had altered spectroscopic properties. X-ray absorption spectroscopy reveals a four-coordinate planar site with N 2S 2-donor ligands, consistent with electronic absorption spectroscopic results indicating that the Ni center in H1*-NiSOD is mostly reduced in the as-isolated sample, as opposed to 50:50 Ni(II)/Ni(III) mixture that is typical for the recombinant wild-type enzyme. The EPR spectrum of as-isolated H1*-NiSOD accounts for ~11% of the Ni in the sample and is similar to WT-NiSOD, but more axial, with g z < g x,y. 14N-hyperfine is observed on g z« less

Cytosolic superoxide dismutase can provide protection against Fasciola gigantica.

PubMed

Jaikua, Wipaphorn; Kueakhai, Pornanan; Chaithirayanon, Kulathida; Tanomrat, Rataya; Wongwairot, Sirima; Riengrojpitak, Suda; Sobhon, Prasert; Changklungmoa, Narin

2016-10-01

Superoxide dismutases (SOD), antioxidant metallo-enzymes, are a part of the first line of defense in the trematode parasites which act as the chief scavengers for reactive oxygen species (ROS). A recombinant Fasciola gigantica cytosolic SOD (FgSOD) was expressed in Escherichia coli BL21 (DE3) and used for immunizing rabbits to obtain polyclonal antibodies (anti-rFgSOD). This rabbit anti-rFgSOD reacted with the native FgSOD at a molecular weight of 17.5kDa. The FgSOD protein was expressed at high level in parenchyma, caecal epithelium and egg of the parasite. The rFgSOD reacted with antisera from rabbits infected with F. gigantica metacercariae collected at 2, 5, and 7 weeks after infection, and reacted with sera of infected mice. Anti-rFgSOD exhibited cross reactivity with the other parasites' antigens, including Eurytrema pancreaticum, Cotylophoron cotylophorum, Fischoederius cobboldi, Gastrothylax crumenifer, Paramphistomum cervi, and Setaria labiato papillosa. A vaccination was performed in imprinting control region (ICR) mice by subcutaneous injection with 50μg of rFgSOD combined with Freund's adjuvant. At 2 weeks after the second boost, mice were infected with 15 metacercariae by oral route. IgG1 and IgG2a in the immune sera were determined to indicate Th2 and Th1 immune responses. It was found that the parasite burden was reduced by 45%, and both IgG1 and IgG2a levels showed correlation with the numbers of worm recoveries. Copyright © 2016 Elsevier B.V. All rights reserved.

Stress fermentation strategies for the production of hyperthermostable superoxide dismutase from Thermus thermophilus HB27: effects of ions.

PubMed

Zhu, Hu; Liu, Jianguo; Qu, Jianbo; Gao, Xinliang; Pan, Tao; Cui, Zhanfeng; Zhao, Xiubo; Lu, Jian R

2013-11-01

In this study, we explored how ammonium and metal ion stresses affected the production of recombinant hyperthermostable manganese superoxide dismutase (Mn-SOD). To improve Mn-SOD production, fed-batch culture in shake flasks and bioreactor fermentation were undertaken to examine the effects of [Formula: see text] and Mn(2+) feeding. Under the optimized feeding time and concentrations of [Formula: see text] and Mn(2+), the maximal SOD activity obtained from bioreactor fermentation reached some 480 U/ml, over 4 times higher than that in batch cultivation (113 U/ml), indicating a major enhancement of the concentration of Mn-SOD in the scale-up of hyperthermostable Mn-SOD production. In contrast, when the fed-batch culture with appropriate [Formula: see text] and Mn(2+) feeding was carried out in the same 5-L stirred tank bioreactor, a maximal SOD concentration of some 450 U/ml was obtained, again indicating substantial increase in SOD activity as a result of [Formula: see text] and Mn(2+) feeding. The isoelectric point (pI) of the sample was found to be 6.2. It was highly stable at 90 °C and circular dichroism measurements indicated a high α-helical content of 70 % as well, consistent with known SOD properties. This study indicates that [Formula: see text] and Mn(2+) play important roles in Mn-SOD expression. Stress fermentation strategies established in this study are useful for large-scale efficient production of hyperthermostable Mn-SOD and may also be valuable for the scale-up of other extremozymes.

Zein-alginate based oral drug delivery systems: Protection and release of therapeutic proteins.

PubMed

Lee, Sungmun; Kim, Yeu-Chun; Park, Ji-Ho

2016-12-30

Reactive oxygen species (ROS) play an important role in the development of inflammatory bowel diseases. Superoxide dismutase (SOD) has a great therapeutic potential by scavenging superoxide that is one of ROS; however, in vivo application is limited especially when it is orally administered. SOD is easily degraded in vivo by the harsh conditions of gastrointestinal tract. Here, we design a zein-alginate based oral drug delivery system that protects SOD from the harsh conditions of gastrointestinal tract and releases it in the environment of the small intestine. SOD is encapsulated in zein-alginate nanoparticles (ZAN) via a phase separation method. We demonstrate that ZAN protect SOD from the harsh conditions of the stomach or small intestine condition. ZAN (200:40) at the weight ratio of 200mg zein to 40mg of alginate releases SOD in a pH dependent manner, and it releases 90.8±1.2% of encapsulated SOD at pH 7.4 in 2h, while only 11.4±0.4% of SOD was released at pH 1.3. The encapsulation efficiency of SOD in ZAN (200:40) was 62.1±2.0%. SOD in ZAN (200:40) reduced the intracellular ROS level and it saved 88.9±7.5% of Caco-2 cells from the toxic superoxide in 4 hours. Based on the results, zein-alginate based oral drug delivery systems will have numerous applications to drugs that are easily degradable in the harsh conditions of gastrointestinal tract. Copyright © 2016 Elsevier B.V. All rights reserved.

Superiority of PC-SOD to other anti-COPD drugs for elastase-induced emphysema and alteration in lung mechanics and respiratory function in mice.

PubMed

Tanaka, Ken-Ichiro; Sato, Keizo; Aoshiba, Kazutetsu; Azuma, Arata; Mizushima, Tohru

2012-06-15

Bronchodilators (such as ipratropium bromide), steroids (such as fluticasone propionate), and newly developed anti-inflammatory drugs (such as roflumilast) are used for patients with chronic obstructive pulmonary disease (COPD). We recently reported that lecithinized superoxide dismutase (PC-SOD) confers a protective effect in mouse models of COPD. We here examined the therapeutic effect of the combined administration of PC-SOD with ipratropium bromide on pulmonary emphysema and compared the effect of PC-SOD to other types of drugs. The severity of emphysema in mice was assessed by various criteria. Lung mechanics (elastance) and respiratory function (ratio of forced expiratory volume in the first 0.05 s to forced vital capacity) were assessed. Administration of PC-SOD by inhalation suppressed elastase-induced pulmonary emphysema, alteration of lung mechanics, and respiratory dysfunction. The concomitant intratracheal administration of ipratropium bromide did not alter the ameliorating effects of PC-SOD. Administration of ipratropium bromide, fluticasone propionate, or roflumilast alone did not suppress the elastase-induced increase in the pulmonary level of superoxide anion, pulmonary inflammatory response, pulmonary emphysema, alteration of lung mechanics, or respiratory dysfunction as effectively as did PC-SOD. PC-SOD, but not the other drugs, showed a therapeutic effect even when the drug was administered after the development of emphysema. PC-SOD also suppressed the cigarette smoke-induced pulmonary inflammatory response and increase in airway resistance. Based on these results, we consider that the inhalation of PC-SOD would be therapeutically beneficial for COPD.

Fisetin Exerts Antioxidant and Neuroprotective Effects in Multiple Mutant hSOD1 Models of Amyotrophic Lateral Sclerosis by Activating ERK.

PubMed

Wang, T H; Wang, S Y; Wang, X D; Jiang, H Q; Yang, Y Q; Wang, Y; Cheng, J L; Zhang, C T; Liang, W W; Feng, H L

2018-05-21

Oxidative stress exhibits a central role in the course of amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative disease commonly found to include a copper/zinc superoxide dismutase (SOD1) gene mutation. Fisetin, a natural antioxidant, has shown benefits in varied neurodegenerative diseases. The possible effect of fisetin in ALS has not been clarified as of yet. We investigated whether fisetin affected mutant hSOD1 ALS models. Three different hSOD1-related mutant models were used: Drosophila expressing mutant hSOD1 G85R , hSOD1 G93A NSC34 cells, and transgenic mice. Fisetin treatment provided neuroprotection as demonstrated by an improved survival rate, attenuated motor impairment, reduced ROS damage and regulated redox homeostasis compared with those in controls. Furthermore, fisetin increased the expression of phosphorylated ERK and upregulated antioxidant factors, which were reversed by MEK/ERK inhibition. Finally, fisetin reduced the levels of both mutant and wild-type hSOD1 in vivo and in vitro, as well as the levels of detergent-insoluble hSOD1 proteins. The results indicate that fisetin protects cells from ROS damage and improves the pathological behaviors caused by oxidative stress in disease models related to SOD1 gene mutations probably by activating ERK, thereby providing a potential treatment for ALS. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

Role of Superoxide Dismutase 2 Gene Ala16Val Polymorphism and Total Antioxidant Capacity in Diabetes and its Complications

PubMed Central

Pourvali, Katayoun; Abbasi, Mehrnaz; Mottaghi, Azadeh

2016-01-01

Diabetes Mellitus (DM) is a chronic heterogeneous disorder and oxidative stress is a key participant in the development and progression of it and its complications. Anti-oxidant status can affect vulnerability to oxidative damage, onset and progression of diabetes and diabetes complications. Superoxide dismutase 2 (SOD2) is one of the major antioxidant defense systems against free radicals. SOD2 is encoded by the nuclear SOD2 gene located on the human chromosome 6q25 and the Ala16Val polymorphism has been identified in exon 2 of the human SOD2 gene. Ala16Val (rs4880) is the most commonly studied SOD2 single nucleotide polymorphism (SNP) in SOD2 gene. This SNP changes the amino acid at position 16 from valine (Val) to alanine (Ala), which has been shown to cause a conformational change in the target sequence of manganese superoxide dismutase (MnSOD) and also affects MnSOD activity in mitochondria. Ala16Val SNP and changes in the activity of the SOD2 antioxidant enzyme have been associated with altered progression and risk of different diseases. Association of this SNP with diabetes and some of its complications have been studied in numerous studies. This review evaluated how rs4880, oxidative stress and antioxidant status are associated with diabetes and its complications although some aspects of this line still remain unclear. PMID:27141263

Intestinal cell targeting of a stable recombinant Cu-Zn SOD from Cucumis melo fused to a gliadin peptide.

PubMed

Intes, Laurent; Bahut, Muriel; Nicole, Pascal; Couvineau, Alain; Guette, Catherine; Calenda, Alphonse

2012-05-31

The mRNA encoding full length chloroplastic Cu-Zn SOD (superoxide dismutase) of Cucumis melo (Cantaloupe melon) was cloned. This sequence was then used to generate a mature recombinant SOD by deleting the first 64 codons expected to encode a chloroplastic peptide signal. A second hybrid SOD was created by inserting ten codons to encode a gliadin peptide at the N-terminal end of the mature SOD. Taking account of codon bias, both recombinant proteins were successfully expressed and produced in Escherichia coli. Both recombinant SODs display an enzymatic activity of ~5000U mg(-1) and were shown to be stable for at least 4h at 37°C in biological fluids mimicking the conditions of intestinal transit. These recombinant proteins were capable in vitro, albeit at different levels, of reducing ROS-induced-apoptosis of human epithelial cells. They also stimulated production and release in a time-dependent manner of an autologous SOD activity from cells located into jejunum biopsies. Nevertheless, the fused gliadin peptide enable the recombinant Cu-Zn SOD to maintain a sufficiently sustained interaction with the intestinal cells membrane in vivo rather than being eliminated with the flow. According to these observations, the new hybrid Cu-Zn SOD should show promise in applications for managing inflammatory bowel diseases. Copyright © 2012 Elsevier B.V. All rights reserved.

SOD2 deficiency in hematopoietic cells in mice results in reduced red blood cell deformability and increased heme degradation

PubMed Central

Mohanty, Joy G.; Nagababu, Enika; Friedman, Jeffrey S.; Rifkind, Joseph M.

2013-01-01

Among the three types of super oxide dismutases (SODs) known, SOD2 deficiency is lethal in neonatal mice owing to cardiomyopathy caused by severe oxidative damage. SOD2 is found in red blood cell (RBC) precursors, but not in mature RBCs. To investigate the potential damage to mature RBCs resulting from SOD2 deficiency in precursor cells, we studied RBCs from mice in which fetal liver stem cells deficient in SOD2 were capable of efficiently rescuing lethally irradiated host animals. These transplanted animals lack SOD2 only in hematopoietically generated cells and live longer than SOD2 knockouts. In these mice, approximately 2.8% of their total RBCs in circulation are iron-laden reticulocytes, with numerous siderocytic granules and increased protein oxidation similar to that seen in sideroblastic anemia. We have studied the RBC deformability and oxidative stress in these animals and the control group by measuring them with a microfluidic ektacytometer and assaying fluorescent heme degradation products with a fluorimeter, respectively. In addition, the rate of hemoglobin oxidation in RBCs from these mice and the control group were measured spectrophotometrically. The results show that RBCs from these SOD2-deficient mice have reduced deformability, increased heme degradation products, and an increased rate of hemoglobin oxidation compared with control animals, indicative of increased RBC oxidative stress. PMID:23142655

Targeting superoxide dismutase to endothelial caveolae profoundly alleviates inflammation caused by endotoxin.

PubMed

Shuvaev, Vladimir V; Kiseleva, Raisa Yu; Arguiri, Evguenia; Villa, Carlos H; Muro, Silvia; Christofidou-Solomidou, Melpo; Stan, Radu V; Muzykantov, Vladimir R

2018-02-28

Inflammatory mediators binding to Toll-Like receptors (TLR) induce an influx of superoxide anion in the ensuing endosomes. In endothelial cells, endosomal surplus of superoxide causes pro-inflammatory activation and TLR4 agonists act preferentially via caveolae-derived endosomes. To test the hypothesis that SOD delivery to caveolae may specifically inhibit this pathological pathway, we conjugated SOD with antibodies (Ab/SOD, size ~10nm) to plasmalemmal vesicle-associated protein (Plvap) that is specifically localized to endothelial caveolae in vivo and compared its effects to non-caveolar target CD31/PECAM-1. Plvap Ab/SOD bound to endothelial cells in culture with much lower efficacy than CD31 Ab/SOD, yet blocked the effects of LPS signaling with higher efficiency than CD31 Ab/SOD. Disruption of cholesterol-rich membrane domains by filipin inhibits Plvap Ab/SOD endocytosis and LPS signaling, implicating the caveolae-dependent pathway(s) in both processes. Both Ab/SOD conjugates targeted to Plvap and CD31 accumulated in the lungs after IV injection in mice, but the former more profoundly inhibited LPS-induced pulmonary inflammation and elevation of plasma level of interferon-beta and -gamma and interleukin-27. Taken together, these results indicate that targeted delivery of SOD to specific cellular compartments may offer effective, mechanistically precise interception of pro-inflammatory signaling mediated by reactive oxygen species. Copyright © 2018 Elsevier B.V. All rights reserved.

Isoenzymes of superoxide dismutase in nodules of Phaseolus vulgaris L. , Pisum sativum L. , and Vigna unguiculata (L. ) Walp

DOE Office of Scientific and Technical Information (OSTI.GOV)

Becana, M.; Paris, F.J.; Sandalio, L.M.

1989-08-01

The activity and isozymic composition of superoxide dismutase were determined in nodules of Phaseolus vulgaris L., Pisum sativum L., and Vigna unguiculata (L.) Walp. A Mn-SOD was present in Rhizobium and two in Bradyrhizobium and bacteroids. Nodule mitochondria from all three legume species had a single Mn-SOD with similar relative mobility, whereas the cytosol contained several CuZn-SODs: two in Phaseolus and Pisum, and four in Vigna. In the cytoplasm of V. unguiculata nodules, a Fe-containing SOD was also present, with an electrophoretic mobility between those of CuZn- and Mn-SODs, and an estimated molecular weight of 57,000. Total SOD activity ofmore » the soluble fraction of host cells, expressed on a nodule fresh weight basis, exceeded markedly that of bacteroids. Likewise, specific SOD activities of free-living bacteria were superior or equal to those of their symbiotic forms. Soluble extracts of bacteria and bacteroids did not show peroxidase activity, but the nodule cell cytoplasm contained diverse peroxidase isozymes which were readily distinguishable from leghemoglobin components by electrophoresis. Data indicated that peroxidases and leghemoglobins did not significantly interfere with SOD localization on gels. Treatment with chloroform-ethanol scarcely affected the isozymic pattern of SODs and peroxidases, and had limited success in the removal of leghemoglobin.« less

TFE-induced local unfolding and fibrillation of SOD1: bridging the experiment and simulation studies.

PubMed

Kumar, Vijay; Prakash, Amresh; Pandey, Preeti; Lynn, Andrew M; Hassan, Md Imtaiyaz

2018-05-18

Misfolding and aggregation of Cu, Zn Superoxide dismutase (SOD1) is involved in the neurodegenerative disease, amyotrophic lateral sclerosis. Many studies have shown that metal-depleted, monomeric form of SOD1 displays substantial local unfolding dynamics and is the precursor for aggregation. Here, we have studied the structure and dynamics of different apo monomeric SOD1 variants associated with unfolding and aggregation in aqueous trifluoroethanol (TFE) through experiments and simulation. TFE induces partially unfolded β-sheet-rich extended conformations in these SOD1 variants, which subsequently develops aggregates with fibril-like characteristics. Fibrillation was achieved more easily in disulfide-reduced monomeric SOD1 when compared with wild-type and mutant monomeric SOD1. At higher concentrations of TFE, a native-like structure with the increase in α-helical content was observed. The molecular dynamics simulation results illustrate distinct structural dynamics for different regions of SOD1 variants and show uniform local unfolding of β-strands. The strands protected by the zinc-binding and electrostatic loops were found to unfold first in 20% (v/v) TFE, leading to a partial unfolding of β-strands 4, 5, and 6 which are prone to aggregation. Our results thus shed light on the role of local unfolding and conformational dynamics in SOD1 misfolding and aggregation. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

A Drosophila Model for Amyotrophic Lateral Sclerosis Reveals Motor Neuron Damage by Human SOD1*♦

PubMed Central

Watson, Melanie R.; Lagow, Robert D.; Xu, Kexiang; Zhang, Bing; Bonini, Nancy M.

2008-01-01

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease that leads to loss of motor function and early death. About 5% of cases are inherited, with the majority of identified linkages in the gene encoding copper, zinc-superoxide dismutase (SOD1). Strong evidence indicates that the SOD1 mutations confer dominant toxicity on the protein. To provide new insight into mechanisms of ALS, we have generated and characterized a model for familial ALS in Drosophila with transgenic expression of human SOD1. Expression of wild type or disease-linked (A4V, G85R) mutants of human SOD1 selectively in motor neurons induced progressive climbing deficits. These effects were accompanied by defective neural circuit electrophysiology, focal accumulation of human SOD1 protein in motor neurons, and a stress response in surrounding glia. However, toxicity was not associated with oligomerization of SOD1 and did not lead to neuronal loss. These studies uncover cell-autonomous injury by SOD1 to motor neurons in vivo, as well as non-autonomous effects on glia, and provide the foundation for new insight into injury and protection of motor neurons in ALS. PMID:18596033

Transduced human copper chaperone for Cu,Zn-SOD (PEP-1-CCS) protects against neuronal cell death.

PubMed

Choi, Soo Hyun; Kim, Dae Won; Kim, So Young; An, Jae Jin; Lee, Sun Hwa; Choi, Hee Soon; Sohn, Eun Jung; Hwang, Seok-Il; Won, Moo Ho; Kang, Tae-Cheon; Kwon, Hyung Joo; Kang, Jung Hoon; Cho, Sung-Woo; Park, Jinseu; Eum, Won Sik; Choi, Soo Young

2005-12-31

Reactive oxygen species (ROS) contribute to the development of various human diseases. Cu,Zn-superoxide dismutase (SOD) is one of the major means by which cells counteract the deleterious effects of ROS. SOD activity is dependent upon bound copper ions supplied by its partner metallochaperone protein, copper chaperone for SOD (CCS). In the present study, we investigated the protective effects of PEP-1-CCS against neuronal cell death and ischemic insults. When PEP-1-CCS was added to the culture medium of neuronal cells, it rapidly entered the cells and protected them against paraquat-induced cell death. Moreover, transduced PEP-1-CCS markedly increased endogenous SOD activity in the cells. Immunohistochemical analysis revealed that it prevented neuronal cell death in the hippocampus in response to transient forebrain ischemia. These results suggest that CCS is essential to activate SOD, and that transduction of PEP-1-CCS provides a potential strategy for therapeutic delivery in various human diseases including stroke related to SOD or ROS.

Copper Homeostasis as a Therapeutic Target in Amyotrophic Lateral Sclerosis with SOD1 Mutations

PubMed Central

Tokuda, Eiichi; Furukawa, Yoshiaki

2016-01-01

Amyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disease affecting both upper and lower motor neurons, and currently, there is no cure or effective treatment. Mutations in a gene encoding a ubiquitous antioxidant enzyme, Cu,Zn-superoxide dismutase (SOD1), have been first identified as a cause of familial forms of ALS. It is widely accepted that mutant SOD1 proteins cause the disease through a gain in toxicity but not through a loss of its physiological function. SOD1 is a major copper-binding protein and regulates copper homeostasis in the cell; therefore, a toxicity of mutant SOD1 could arise from the disruption of copper homeostasis. In this review, we will briefly review recent studies implying roles of copper homeostasis in the pathogenesis of SOD1-ALS and highlight the therapeutic interventions focusing on pharmacological as well as genetic regulations of copper homeostasis to modify the pathological process in SOD1-ALS. PMID:27136532

Copper Homeostasis as a Therapeutic Target in Amyotrophic Lateral Sclerosis with SOD1 Mutations.

PubMed

Tokuda, Eiichi; Furukawa, Yoshiaki

2016-04-28

Amyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disease affecting both upper and lower motor neurons, and currently, there is no cure or effective treatment. Mutations in a gene encoding a ubiquitous antioxidant enzyme, Cu,Zn-superoxide dismutase (SOD1), have been first identified as a cause of familial forms of ALS. It is widely accepted that mutant SOD1 proteins cause the disease through a gain in toxicity but not through a loss of its physiological function. SOD1 is a major copper-binding protein and regulates copper homeostasis in the cell; therefore, a toxicity of mutant SOD1 could arise from the disruption of copper homeostasis. In this review, we will briefly review recent studies implying roles of copper homeostasis in the pathogenesis of SOD1-ALS and highlight the therapeutic interventions focusing on pharmacological as well as genetic regulations of copper homeostasis to modify the pathological process in SOD1-ALS.

In-cell NMR reveals potential precursor of toxic species from SOD1 fALS mutants

NASA Astrophysics Data System (ADS)

Luchinat, Enrico; Barbieri, Letizia; Rubino, Jeffrey T.; Kozyreva, Tatiana; Cantini, Francesca; Banci, Lucia

2014-11-01

Mutations in the superoxide dismutase 1 (SOD1) gene are related to familial cases of amyotrophic lateral sclerosis (fALS). Here we exploit in-cell NMR to characterize the protein folding and maturation of a series of fALS-linked SOD1 mutants in human cells and to obtain insight into their behaviour in the cellular context, at the molecular level. The effect of various mutations on SOD1 maturation are investigated by changing the availability of metal ions in the cells, and by coexpressing the copper chaperone for SOD1, hCCS. We observe for most of the mutants the occurrence of an unstructured SOD1 species, unable to bind zinc. This species may be a common precursor of potentially toxic oligomeric species, that are associated with fALS. Coexpression of hCCS in the presence of copper restores the correct maturation of the SOD1 mutants and prevents the formation of the unstructured species, confirming that hCCS also acts as a molecular chaperone.

Copper-zinc superoxide dismutase is activated through a sulfenic acid intermediate at a copper ion entry site.

PubMed

Fetherolf, Morgan M; Boyd, Stefanie D; Taylor, Alexander B; Kim, Hee Jong; Wohlschlegel, James A; Blackburn, Ninian J; Hart, P John; Winge, Dennis R; Winkler, Duane D

2017-07-21

Metallochaperones are a diverse family of trafficking molecules that provide metal ions to protein targets for use as cofactors. The copper chaperone for superoxide dismutase (Ccs1) activates immature copper-zinc superoxide dismutase (Sod1) by delivering copper and facilitating the oxidation of the Sod1 intramolecular disulfide bond. Here, we present structural, spectroscopic, and cell-based data supporting a novel copper-induced mechanism for Sod1 activation. Ccs1 binding exposes an electropositive cavity and proposed "entry site" for copper ion delivery on immature Sod1. Copper-mediated sulfenylation leads to a sulfenic acid intermediate that eventually resolves to form the Sod1 disulfide bond with concomitant release of copper into the Sod1 active site. Sod1 is the predominant disulfide bond-requiring enzyme in the cytoplasm, and this copper-induced mechanism of disulfide bond formation obviates the need for a thiol/disulfide oxidoreductase in that compartment. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Reduced superoxide dismutase activity in xeroderma pigmentosum fibroblasts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nishigori, C.; Miyachi, Y.; Imamura, S.

1989-10-01

This study was performed in order to assess the possible protective effect of superoxide dismutase (SOD) on ultraviolet (UV) damage in xeroderma pigmentosum (XP) fibroblasts. SOD activity in fibroblasts originating from seven xeroderma pigmentosum (XP) patients was significantly lower than that in normal cells (p less than 0.005). Average SOD activity in XP cells belonging to complementation group A was 3.68 +/- 0.54 (n = 7) and that in normal human cells was 5.79 +/- 1.59 (n = 6). Addition of SOD before and during UV irradiation (UVB and UVC) to the cells caused no change in the amount ofmore » unscheduled DNA synthesis and UV survival. A possible involvement of reduced SOD in XP and a possible protective effect by SOD on UV damage is discussed.« less

Copper-zinc-superoxide dismutase (CuZnSOD), an antioxidant gene from seahorse (Hippocampus abdominalis); molecular cloning, sequence characterization, antioxidant activity and potential peroxidation function of its recombinant protein.

PubMed

Perera, N C N; Godahewa, G I; Lee, Jehee

2016-10-01

Copper-zinc-superoxide dismutase (CuZnSOD) from Hippocampus abdominalis (HaCuZnSOD) is a metalloenzyme which belongs to the ubiquitous family of SODs. Here, we determined the characteristic structural features of HaCuZnSOD, analyzed its evolutionary relationships, and identified its potential immune responses and biological functions in relation to antioxidant defense mechanisms in the seahorse. The gene had a 5' untranslated region (UTR) of 67 bp, a coding sequence of 465 bp and a 3' UTR of 313 bp. The putative peptide consists of 154 amino acids. HaCuZnSOD had a predicted molecular mass of 15.94 kDa and a theoretical pI value of 5.73, which is favorable for copper binding activity. In silico analysis revealed that HaCuZnSOD had a prominent Cu-Zn_superoxide_dismutase domain, two Cu/Zn signature sequences, a putative N-glycosylation site, and several active sites including Cu(2+) and Zn(2+) binding sites. The three dimensional structure indicated a β-sheet barrel with 8 β-sheets and two short α-helical regions. Multiple alignment analyses revealed many conserved regions and active sites among its orthologs. The highest amino acid identity to HaCuZnSOD was found in Siniperca chuatsi (87.4%), while Maylandia zebra shared a close relationship in the phylogenetic analysis. Functional assays were performed to assess the antioxidant, biophysical and biochemical properties of overexpressed recombinant (r) HaCuZnSOD. A xanthine/XOD assay gave optimum results at pH 9 and 25 °C indicating these may be the best conditions for its antioxidant action in the seahorse. An MTT assay and flow cytometry confirmed that rHaCuZnSOD showed peroxidase activity in the presence of HCO3(-). In all the functional assays, the level of antioxidant activity of rHaCuZnSOD was concentration dependent; metal ion supplementation also increased its activity. The highest mRNA expressional level of HaCuZnSOD was found in blood. Temporal assessment under pathological stress showed a delay response by HaCuZnSOD. Our findings demonstrated that HaCuZnSOD is an important antioxidant, which might be involved in the host antioxidant defense mechanism against oxidative stress. Copyright © 2016 Elsevier Ltd. All rights reserved.

AMELIORATION OF ETHANOL-INDUCED DYSMORPHOGENESIS BY ADENOVIRAL-MEDIATED CU,ZN-SOD AND MN-SOD EXPRESSION IN NEURULATION STAGED MOUSE EMBRYOS IN VITRO

EPA Science Inventory

AMELIORATION OF ETHANOL-INDUCED DYSMORPHOGENESIS BY ADENOVIRAL-MEDIATED Cu,Zn-SOD AND Mn-SOD EXPRESSION IN NEURULATION STAGED MOUSE EMBRYOS IN VITRO. JB Smith1, PC Hartig3, MR Blanton3, KK Sulik1,2, and ES Hunter3. 1Department of Cell and Developmental Biology and 2Bowles Cente...

SIRT1 overexpression ameliorates a mouse model of SOD1-linked amyotrophic lateral sclerosis via HSF1/HSP70i chaperone system.

PubMed

Watanabe, Seiji; Ageta-Ishihara, Natsumi; Nagatsu, Shinji; Takao, Keizo; Komine, Okiru; Endo, Fumito; Miyakawa, Tsuyoshi; Misawa, Hidemi; Takahashi, Ryosuke; Kinoshita, Makoto; Yamanaka, Koji

2014-08-29

Dominant mutations in superoxide dismutase 1 (SOD1) cause degeneration of motor neurons in a subset of inherited amyotrophic lateral sclerosis (ALS). The pathogenetic process mediated by misfolded and/or aggregated mutant SOD1 polypeptides is hypothesized to be suppressed by protein refolding. This genetic study is aimed to test whether mutant SOD1-mediated ALS pathology recapitulated in mice could be alleviated by overexpressing a longevity-related deacetylase SIRT1 whose substrates include a transcription factor heat shock factor 1 (HSF1), the master regulator of the chaperone system. We established a line of transgenic mice that chronically overexpress SIRT1 in the brain and spinal cord. While inducible HSP70 (HSP70i) was upregulated in the spinal cord of SIRT1 transgenic mice (PrP-Sirt1), no neurological and behavioral alterations were detected. To test hypothetical benefits of SIRT1 overexpression, we crossbred PrP-Sirt1 mice with two lines of ALS model mice: A high expression line that exhibits a severe phenotype (SOD1G93A-H) or a low expression line with a milder phenotype (SOD1G93A-L). The Sirt1 transgene conferred longer lifespan without altering the time of symptomatic onset in SOD1G93A-L. Biochemical analysis of the spinal cord revealed that SIRT1 induced HSP70i expression through deacetylation of HSF1 and that SOD1G93A-L/PrP-Sirt1 double transgenic mice contained less insoluble SOD1 than SOD1G93A-L mice. Parallel experiments showed that Sirt1 transgene could not rescue a more severe phenotype of SOD1G93A-H transgenic mice partly because their HSP70i level had peaked out. The genetic supplementation of SIRT1 can ameliorate a mutant SOD1-linked ALS mouse model partly through the activation of the HSF1/HSP70i chaperone system. Future studies shall include testing potential benefits of pharmacological enhancement of the deacetylation activity of SIRT1 after the onset of the symptom.

Role of superoxide–nitric oxide interactions in the accelerated age-related loss of muscle mass in mice lacking Cu,Zn superoxide dismutase

PubMed Central

Sakellariou, Giorgos K; Pye, Deborah; Vasilaki, Aphrodite; Zibrik, Lea; Palomero, Jesus; Kabayo, Tabitha; McArdle, Francis; Van Remmen, Holly; Richardson, Arlan; Tidball, James G; McArdle, Anne; Jackson, Malcolm J

2011-01-01

Summary Mice lacking Cu,Zn superoxide dismutase (SOD1) show accelerated, age-related loss of muscle mass. Lack of SOD1 may lead to increased superoxide, reduced nitric oxide (NO), and increased peroxynitrite, each of which could initiate muscle fiber loss. Single muscle fibers from flexor digitorum brevis of wild-type (WT) and Sod1−/− mice were loaded with NO-sensitive (4-amino-5-methylamino-2′,7′-difluorofluorescein diacetate, DAF-FM) and superoxide-sensitive (dihydroethidium, DHE) probes. Gastrocnemius muscles were analyzed for SOD enzymes, nitric oxide synthases (NOS), and 3-nitrotyrosine (3-NT) content. A lack of SOD1 did not increase superoxide availability at rest because no increase in ethidium or 2-hydroxyethidium (2-HE) formation from DHE was seen in fibers from Sod1−/− mice compared with those from WT mice. Fibers from Sod1−/− mice had decreased NO availability (decreased DAF-FM fluorescence), increased 3-NT in muscle proteins indicating increased peroxynitrite formation and increased content of peroxiredoxin V (a peroxynitrite reductase), compared with WT mice. Muscle fibers from Sod1−/− mice showed substantially reduced generation of superoxide in response to contractions compared with fibers from WT mice. Inhibition of NOS did not affect DHE oxidation in fibers from WT or Sod1−/− mice at rest or during contractions, but transgenic mice overexpressing nNOS showed increased DAF-FM fluorescence and reduced DHE oxidation in resting muscle fibers. It is concluded that formation of peroxynitrite in muscle fibers is a major effect of lack of SOD1 in Sod1−/− mice and may contribute to fiber loss in this model, and that NO regulates superoxide availability and peroxynitrite formation in muscle. PMID:21443684

Molecular Responses to Photooxidative Stress in Pinus sylvestris (L.) (II. Differential Expression of CuZn-Superoxide Dismutases and Glutathione Reductase.

PubMed Central

Karpinski, S.; Wingsle, G.; Karpinska, B.; Hallgren, J. E.

1993-01-01

The influence of photooxidative stress on genes expressing superoxide dismutase (Sod) and glutathione reductase (Gor) was analyzed in needles of top and side shoots of 3-year-old Pinus sylvestris (L.) seedlings. The study was carried out in the field during spring recovery. From mid-April the top shoots of seedlings protruded above the snow and thus were exposed to sunlight, whereas the side shoots were covered with snow until May 4. Needles were sampled from top and side shoots on five different occasions. At the beginning of May the mRNA levels for cytosolic CuZn-Sod were significantly higher in top-shoot needles than in side-shoot needles. Similar results were obtained for chloroplastic CuZn-Sod mRNA. After May 6 we could not detect any significant differences between top- and side-shoot needles for either CuZn-Sod mRNA level. Transcript accumulation for the chloroplastic CuZn-Sod was up to 4-fold higher than for cytosolic CuZn-Sod in both types of shoots. On June 1 minimum transcript levels were observed for both CuZn-SOD isoforms. Protein activity analysis for CuZn-SOD isozymes did not reveal any significant differences between top- and side-shoot needles during the whole period of measurements. The mRNA level for chloroplastic Gor was similar in both types of shoots. However, the total GR activity was significantly higher in top-shoot needles than in side-shoot needles at the beginning of May. The analysis of mRNA accumulation for chloroplastic CuZn-Sod and Gor indicates that transcript levels were at least 5- to 20-fold higher for CuZn-Sod than for chloroplastic Gor. The differential expressions of Sod and Gor genes are discussed in relation to regulation of the enzymic scavenging system during photooxidative stress conditions. PMID:12232032

In-vivo effects of knocking-down metabotropic glutamate receptor 5 in the SOD1G93A mouse model of amyotrophic lateral sclerosis.

PubMed

Bonifacino, Tiziana; Cattaneo, Luca; Gallia, Elena; Puliti, Aldamaria; Melone, Marcello; Provenzano, Francesca; Bossi, Simone; Musante, Ilaria; Usai, Cesare; Conti, Fiorenzo; Bonanno, Giambattista; Milanese, Marco

2017-09-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder due to loss of upper and lower motor neurons (MNs). The mechanisms of neuronal death are largely unknown, thus prejudicing the successful pharmacological treatment. One major cause for MN degeneration in ALS is represented by glutamate(Glu)-mediated excitotoxicity. We have previously reported that activation of Group I metabotropic Glu receptors (mGluR1 and mGluR5) at glutamatergic spinal cord nerve terminals produces abnormal Glu release in the widely studied SOD1 G93A mouse model of ALS. We also demonstrated that halving mGluR1 expression in the SOD1 G93A mouse had a positive impact on survival, disease onset, disease progression, and on a number of cellular and biochemical readouts of ALS. We generated here SOD1 G93A mice with reduced expression of mGluR5 (SOD1 G93A Grm5 -/+ ) by crossing the SOD1 G93A mutant mouse with the mGluR5 heterozigous Grm5 -/+ mouse. SOD1 G93A Grm5 -/+ mice showed prolonged survival probability and delayed pathology onset. These effects were associated to enhanced number of preserved MNs, decreased astrocyte and microglia activation, reduced cytosolic free Ca 2+ concentration, and regularization of abnormal Glu release in the spinal cord of SOD1 G93A Grm5 -/+ mice. Unexpectedly, only male SOD1 G93A Grm5 -/+ mice showed improved motor skills during disease progression vs. SOD1 G93A mice, while SOD1 G93A Grm5 -/+ females did not. These results demonstrate that a lower constitutive level of mGluR5 has a significant positive impact in mice with ALS and support the idea that blocking Group I mGluRs may represent a potentially effective pharmacological approach to the disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of recombinant human extracellular-superoxide dismutase type C on myocardial infarct size in pigs.

PubMed

Hatori, N; Sjöquist, P O; Marklund, S L; Rydén, L

1992-09-01

The efficacy of human extracellular-superoxide dismutase type C (EC-SOD C) to limit infarct size after ischemia and reperfusion was explored and compared to that of EC-SOD C combined with catalase (CAT) and to that of CAT alone. EC-SOD C binds to heparan sulphate proteoglycan on the cell surfaces. Thirty-two pigs were subjected to 45 min of myocardial ischemia followed by 4 h of reperfusion. Control pigs (group A; n = 8) received 300 mL of saline into the great cardiac vein during a 30-min period started 5 min prior to reperfusion; pigs in group B (EC-SOD C; n = 8) got 16.6 mg of EC-SOD C; pigs in group C (EC-SOD C + CAT; n = 8) got 16.6 mg of EC-SOD C together with 150 mg of CAT. Pigs in group D (CAT; n = 8) received 150 mg of CAT. In groups B, C, and D, the drug was dissolved in saline and infused into the great cardiac. Infarct size expressed as percent of area at risk was smaller in groups B (14.5 +/- 16.7%) and C (40.8 +/- 13.3%) than in groups A (78.8 +/- 8.6%) and D (67.2 +/- 18.6%; p less than .05). Creatine kinase (CK) activity in ischemic myocardium was higher in groups B (1740 +/- 548 U/g) and C (1729 +/- 358 U/g) than in groups A (1184 +/- 237 U/g) and D (1251 +/- 434 U/g; p less than .05). There was an inverse relation (r = -.83) between infarct size and CK content. The EC-SOD C infusions resulted in only minimal increases in plasma SOD activities. In conclusion, the presence of SOD on the cell surfaces is of importance in the prevention of reperfusion injury rather than circulating SOD.

Effects of Aging and Oxidative Stress on Spermatozoa of Superoxide-Dismutase 1- and Catalase-Null Mice.

PubMed

Selvaratnam, Johanna S; Robaire, Bernard

2016-09-01

Advanced paternal age is linked to complications in pregnancy and genetic diseases in offspring. Aging results in excess reactive oxygen species (ROS) and DNA damage in spermatozoa; this damage can be transmitted to progeny with detrimental consequences. Although there is a loss of antioxidants with aging, the impact on aging male germ cells of the complete absence of either catalase (CAT) or superoxide dismutase 1 (SOD1) has not been investigated. We used CAT-null (Cat(-/-)) and SOD1-null (Sod(-/-)) mice to determine whether loss of these antioxidants increases germ cell susceptibility to redox dysfunction with aging. Aging reduced fertility and the numbers of Sertoli and germ cells in all mice. Aged Sod(-/-) mice displayed an increased loss of fertility compared to aged wild-type mice. Treatment with the pro-oxidant SIN-10 increased ROS in spermatocytes of aged wild-type and Sod(-/-) mice, while aged Cat(-/-) mice were able to neutralize this ROS. The antioxidant peroxiredoxin 1 (PRDX1) increased with age in wild-type and Cat(-/-) mice but was consistently low in young and aged Sod(-/-) mice. DNA damage and repair markers (γ-H2AX and 53BP1) were reduced with aging and lower in young Sod(-/-) and Cat(-/-) mice. Colocalization of γ-H2AX and 53BP1 suggested active repair in young wild-type mice but reduced in young Cat(-/-) and in Sod(-/-) mice and with age. Oxidative DNA damage (8-oxodG) increased in young Sod(-/-) mice and with age in all mice. These studies show that aged Sod(-/-) mice display severe redox dysfunction, while wild-type and Cat(-/-) mice have compensatory mechanisms to partially alleviate oxidative stress and reduce age-related DNA damage in spermatozoa. Thus, SOD1 but not CAT is critical to the maintenance of germ cell quality with aging. © 2016 by the Society for the Study of Reproduction, Inc.

Acetaminophen-Induced Hepatotoxicity in Mice Occurs with Inhibition of Activity and Nitration of Mitochondrial Manganese Superoxide Dismutase

PubMed Central

Agarwal, Rakhee; MacMillan-Crow, Lee Ann; Rafferty, Tonya M.; Saba, Hamida; Roberts, Dean W.; Fifer, E. Kim; James, Laura P.

2011-01-01

In overdose the analgesic/antipyretic acetaminophen (APAP) is hepatotoxic. Toxicity is mediated by initial hepatic metabolism to N-acetyl-p-benzoquinone imine (NAPQI). After low doses NAPQI is efficiently detoxified by GSH. However, in overdose GSH is depleted, NAPQI covalently binds to proteins as APAP adducts, and oxygen/nitrogen stress occurs. Toxicity is believed to occur by mitochondrial dysfunction. Manganese superoxide dismutase (MnSOD) inactivation by protein nitration has been reported to occur during other oxidant stress-mediated diseases. MnSOD is a critical mitochondrial antioxidant enzyme that prevents peroxynitrite formation within the mitochondria. To examine the role of MnSOD in APAP toxicity, mice were treated with 300 mg/kg APAP. GSH was significantly reduced by 65% at 0.5 h and remained reduced from 1 to 4 h. Serum alanine aminotransferase did not significantly increase until 4 h and was 2290 IU/liter at 6 h. MnSOD activity was significantly reduced by 50% at 1 and 2 h. At 1 h, GSH was significantly depleted by 62 and 80% at nontoxic doses of 50 and 100 mg/kg, respectively. No further GSH depletion occurred with hepatotoxic doses of 200 and 300 mg/kg APAP. A dose response decrease in MnSOD activity was observed for APAP at 100, 200, and 300 mg/kg. Immunoprecipitation of MnSOD from livers of APAP-treated mice followed by Western blot analysis revealed nitrated MnSOD. APAP-MnSOD adducts were not detected. Treatment of recombinant MnSOD with NAPQI did not produce APAP protein adducts. The data indicate that MnSOD inactivation by nitration is an early event in APAP-induced hepatic toxicity. PMID:21205919

Effect of different concentrations of oxygen on expression of sigma 1 receptor and superoxide dismutases in human colon adenocarcinoma cell lines.

PubMed

Skrzycki, Michał; Czeczot, Hanna; Mielczarek-Puta, Magdalena; Otto-Ślusarczyk, Dagmara; Graboń, Wojciech

2017-06-01

Tumor cells due to distance from capillary vessels exist in different oxygenation conditions (anoxia, hypoxia, normoxia). Changes in cell oxygenation lead to reactive oxygen species production and oxidative stress. Sigma 1 receptor (Sig1R) is postulated to be stress responding agent and superoxide dismutases (SOD1 and SOD2) are key antioxidant enzymes. It is possible that they participate in tumor cells adaptation to different concentrations of oxygen. Evaluation of Sig1R, SOD1, and SOD2 expression in different concentrations of oxygen (1%, 10%, 21%) in colon adenocarcinoma cell lines. SW480 (primary adenocarcinoma) and SW620 (metastatic) cell lines were cultured in standard conditions in Dulbecco's modified Eagle's medium for 5 days, and next cultured in Hypoxic Chamber in 1% O 2 , 10% O 2 , 21% O 2 . Number of living cells was determined by trypan blue assay. Level of mRNA for Sig1R, SOD1, and SOD2 was determined by standard PCR method. Statistical analysis was conducted using Statistica 10.1 software. We observed significant changes in expression of Sig1R, SOD1, SOD2 due to different oxygen concentrations. ANOVA analysis revealed significant interactions between studied parameters mainly in hypoxia conditions in SW480 cells and between Sig1R and SOD2 in SW620 cells. It also showed that changes in expression of studied proteins depend significantly on type of the cell line. Changes of Sig1R and SOD2 expression point to mitochondria as main organelle responsible for survival of tumor cells exposed to hypoxia or oxidative stress. Studied proteins are involved in intracellular response to stress related with different concentrations of oxygen.

Effects of the peroxisome proliferator clofibric acid on superoxide dismutase expression in the human HepG2 hepatoma cell line.

PubMed

Bécuwe, P; Bianchi, A; Keller, J M; Dauça, M

1999-09-15

We examined the effects of clofibric acid, a peroxisome proliferator, on the production of superoxide radicals, on the levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), and on the expression of superoxide dismutases (SODs) in the human HepG2 hepatoma cell line. To this end, HepG2 cells were treated for 1 or 5 days with 0.25, 0.50, or 0.75 mM clofibric acid. The production of superoxide radicals was only enhanced in HepG2 cells exposed for 5 days to the different clofibric acid concentrations. However, this overproduction of superoxide radicals was not accompanied by increased rates of lipid peroxidation, as the MDA and 4-HNE levels did not change significantly. Manganese (Mn) SOD activity was increased when HepG2 cells were treated for 1 day with 0.50 or 0.75 mM clofibric acid. For this duration of treatment, no change was observed in total SOD and copper/zinc (Cu/Zn) SOD activities. For a 5-day treatment, total SOD and MnSOD activities as well as the enzyme apoprotein and MnSOD mRNA levels increased whatever the clofibric acid concentration used. This transcriptional induction of the MnSOD gene was correlated with an activation of the activator protein-1 transcription factor for 1 and 5 days of treatment, but was independent of nuclear factor-kappa B and of peroxisome proliferator-activated receptor. On the other hand, the PP exerted very little effect if any on Cu,ZnSOD expression. In contrast to rodent data, PP treatment of human hepatoma cells induces MnSOD expression.

Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus

PubMed Central

Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

2009-01-01

Background The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. Methods The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. Results EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Conclusion Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients. PMID:19878539

Imaging of glial cell morphology, SOD1 distribution and elemental composition in the brainstem and hippocampus of the ALS hSOD1G93A rat.

PubMed

Stamenković, Stefan; Dučić, Tanja; Stamenković, Vera; Kranz, Alexander; Andjus, Pavle R

2017-08-15

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder affecting motor and cognitive domains of the CNS. Mutations in the Cu,Zn-superoxide dismutase (SOD1) cause 20% of familial ALS and provoke formation of intracellular aggregates and copper and zinc unbinding, leading to glial activation and neurodegeneration. Therefore, we investigated glial cell morphology, intracellular SOD1 distribution, and elemental composition in the brainstem and hippocampus of the hSOD1 G93A transgenic rat model of ALS. Immunostaining for astrocytes, microglia and SOD1 revealed glial proliferation and progressive tissue accumulation of SOD1 in both brain regions of ALS rats starting already at the presymptomatic stage. Glial cell morphology analysis in the brainstem of ALS rats revealed astrocyte activation occurring before disease symptoms onset, followed by activation of microglia. Hippocampal ALS astrocytes exhibited an identical reactive profile, while microglial morphology was unchanged. Additionally, ALS brainstem astrocytes demonstrated progressive SOD1 accumulation in the cell body and processes, while microglial SOD1 levels were reduced and its distribution limited to distal cell processes. In the hippocampus both glial cell types exhibited SOD1 accumulation in the cell body. X-ray fluorescence imaging revealed decreased P and increased Ca, Cl, K, Ni, Cu and Zn in the brainstem, and higher levels of Cl, Ni and Cu, but lower levels of Zn in the hippocampus of symptomatic ALS rats. These results bring new insights into the glial response during disease development and progression in motor as well as in non-motor CNS structures, and indicate disturbed tissue elemental homeostasis as a prominent hallmark of disease pathology. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Leptin protects cardiomyocytes from serum-deprivation-induced apoptosis by increasing anti-oxidant defence.

PubMed

Zheng, Juan; Fang, Ji; Yin, Yuan-Jun; Wang, Xiao-Chen; Ren, An-Jing; Bai, Jie; Sun, Xue-Jun; Yuan, Wen-Jun; Lin, Li

2010-10-01

1. Leptin, an important adipose-derived hormone, can be associated with cardiac pathophysiology; however, the role of leptin in cardiomyocyte apoptosis is poorly understood. The present study examines serum-deprivation-induced apoptosis in primary cultured cardiomyocytes treated with leptin. 2. Cardiomyocytes were subjected to serum deprivation in the presence or absence of leptin (5 or 50 nmol/L) for 48 h. Apoptosis was determined by Hoechst 33258 and Annexin V-FITC/propidium iodide dual staining. Cell viability, malondialdehyde (MDA) content, caspase 3 activation, and the expression and enzyme activity of superoxide dismutase (SOD) were measured. Small interference RNA (siRNA) targeting SOD1 and SOD2 were used to knockdown their expression and measure apoptosis. 3. Serum deprivation caused nearly 30% of apoptosis in cardiomyocytes, and an approximately 60% decrease in cell viability. The mRNA levels and the activated form of caspase 3 were greatly increased. In the presence of leptin, the apoptotic rate was reduced to approximately 15%, cell viability was increased and the activation of caspase 3 was partially inhibited. Additionally, the augmented lipid peroxidation (MDA formation) was abolished, and the impaired activities of SOD1 and SOD2 were restored by leptin. The mRNA expression of SOD2, but not SOD1, was stimulated by leptin. Transfection with siRNA that cause deficiency of either SOD1 or SOD2 attenuated the anti-apoptotic effects of leptin. 4. The results suggest that leptin inhibits serum-deprivation-induced apoptosis in cardiomyocytes by activating SOD. The present study outlines the direct actions of leptin in cardiac disorders that are related to elevated leptin levels. © 2010 The Authors. Clinical and Experimental Pharmacology and Physiology © 2010 Blackwell Publishing Asia Pty Ltd.

Overexpression of metallothionein-I, a copper-regulating protein, attenuates intracellular copper dyshomeostasis and extends lifespan in a mouse model of amyotrophic lateral sclerosis caused by mutant superoxide dismutase-1.

PubMed

Tokuda, Eiichi; Okawa, Eriko; Watanabe, Shunsuke; Ono, Shin-Ichi

2014-03-01

Over 170 mutations in superoxide dismutase-1 (SOD1) cause familial amyotrophic lateral sclerosis (ALS), a lethal motor neuron disease. Although the molecular properties of SOD1 mutants differ considerably, we have recently shown that intracellular copper dyshomeostasis is a common pathogenic feature of different SOD1 mutants. Thus, the potentiation of endogenous copper regulation could be a therapeutic strategy. In this study, we investigated the effects of the overexpression of metallothionein-I (MT-I), a major copper-regulating protein, on the disease course of a mouse model of ALS (SOD1(G93A)). Using double transgenic techniques, we found that the overexpression of MT-I in SOD1(G93A) mice significantly extended the lifespan and slowed disease progression, but the effects on disease onset were modest. Genetically induced MT-I normalized copper dyshomeostasis in the spinal cord without influencing SOD1 enzymatic activity. The overexpression of MT-I in SOD1(G93A) mice markedly attenuated the pathological features of the mice, including the death of motor neurons, the degeneration of ventral root axons, the atrophy of skeletal muscles, and the activation of glial cells. Double transgenic mice also showed a decreased level of SOD1 aggregates within the glial cells of the spinal cord. Furthermore, the overexpression of MT-I in SOD1(G93A) mice reduced the number of spheroid-shaped astrocytes cleaved by active caspase-3. We concluded that therapeutic strategies aimed at the potentiation of copper regulation by MT-I could be of benefit in cases of ALS caused by SOD1 mutations.

7 CFR 1437.309 - Turfgrass sod.

Code of Federal Regulations, 2012 CFR

2012-01-01

... sod shall be a square yard. (d) Turfgrass sod having any value shall be considered as worth full value... information to CCC regarding the average number of square yards per acre and all unharvested areas. ...

7 CFR 1437.309 - Turfgrass sod.

Code of Federal Regulations, 2014 CFR

2014-01-01

... sod shall be a square yard. (d) Turfgrass sod having any value shall be considered as worth full value... information to CCC regarding the average number of square yards per acre and all unharvested areas. ...

7 CFR 1437.309 - Turfgrass sod.

Code of Federal Regulations, 2013 CFR

2013-01-01

... sod shall be a square yard. (d) Turfgrass sod having any value shall be considered as worth full value... information to CCC regarding the average number of square yards per acre and all unharvested areas. ...

Superoxide dismutase in ripening fruits.

PubMed

Baker, J E

1976-11-01

The levels of superoxide dismutase (SOD) activity in extracts of preclimacteric apple, banana, avocado, and tomato fruits were not greatly different than in extracts of postclimacteric fruits. The results indicate that no major quantitative change in SOD occurs in fruits with or preceding the onset of senescence. Tomato fruit SOD was studied in more detail, and was found largely in the soluble fraction, and to a lesser extent in the mitochondrial and plastid fractions. The soluble fraction was purified by ammonium sulfate fractionation, column chromatography, and isoelectric focusing. Isoelectric focusing separated SOD from contaminating peroxidases. The purified tomato SOD showed an apparent molecular weight of 31,500 determined by gel filtration. Polyacrylamide gel electrophoresis of this preparation indicated two SOD components corresponding to two protein bands, one of which stained more intensely than the other. The purified tomato enzyme was inhibited 90% by 1 mm KCN.

Perkinsus marinus superoxide dismutase 2 (PmSOD2) localizes to single-membrane subcellular compartments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernandez-Robledo, Jose A.; Schott, Eric J.; Vasta, Gerardo R.

2008-10-17

Perkinsus marinus (Phylum Perkinsozoa), a protozoan parasite of oysters, is considered one of the earliest diverging groups of the lineage leading to dinoflagellates. Perkinsus trophozoites are phagocytosed by oyster hemocytes, where they are likely exposed to reactive oxygen species. As part of its reactive oxygen detoxifying pathway, P. marinus possesses two iron-cofactored SOD (PmSOD1 and PmSOD2). Immunoflourescence analysis of P. marinus trophozoites and gene complementation in yeast revealed that PmSOD1 is targeted to the mitochondria. Surprisingly, although PmSOD2 is characterized by a bipartite N-terminus extension typical of plastid targeting, in preliminary immunofluorescence studies it was visualized as punctuate regions inmore » the cytoplasm that could not be assigned to any organelle. Here, we used immunogold electron microscopy to examine the subcellular localization PmSOD2 in P. marinus trophozoites. Gold grains were mostly associated with single-membrane vesicle-like structures, and eventually, localized to electron-dense, apparently amorphous material present in the lumen of a larger, unique compartment. The images suggested that PmSOD2 is targeted to small vesicles that fuse and/or discharge their content into a larger compartment, possibly the large vacuole typical of the mature trophozoites. In light of the in silico targeting prediction, the association of PmSOD2 with single-membrane compartments raises interesting questions regarding its organellar targeting, and the nature of a putative relic plastid in Perkinsus species.« less

MnSOD expression inhibited by electromagnetic pulse radiation in the rat testis.

PubMed

Zeng, LiHua; Ji, XiTuan; Zhang, YanJun; Miao, Xia; Zou, ChangXu; Lang, HaiYang; Zhang, Jie; Li, YuRong; Wang, XiaoWu; Qi, HongXing; Ren, DongQin; Guo, GuoZhen

2011-12-01

Male Sprague Dawley rats were exposed to EMP irradiation of 100 kV/m peak-to-peak e-field intensity and different numbers of pulses. Rat sperm samples were prepared for analysis of sperm qualities; Testes were assessed by transmission electron microscopy and serum hormone concentrations were examined by radioimmunoassay; Enzymatic activities of Total-superoxide dismutase(T-SOD) and manganese-superoxide dismutase (MnSOD), the mRNA levels of MnSOD and cuprozinc-superoxide dismutase (CuZnSOD), and the density of malondialdehyde (MDA) were also determined. EMP irradiation did not affect spermatozoon morphology, micronucleus formation rate, sperm number or viability, but the acrosin reaction rate decreased at 24 h and 48 h and recovered by 72 h after irradiation as compared to the controls. The ultrastructure of rat testis displayed more serious damage at 24 h than at other time points (6 h, 12 h, 48 h). Serum levels of luteotrophic hormone (LH) and testosterone (T) were elevated in irradiated rats as compared to controls. After irradiation, enzymatic activities of T-SOD and MnSOD were reduced by 24 h, consistent with the changes observed in MnSOD mRNA expression; MDA content increased at 6 h in turn. These studies have quantified the morphological damage and dysfunction in the rat reproductive system induced by EMP. The mechanism of EMP induced damage may be associated with the inhibition of MnSOD expression.

Enabling the extended compact genetic algorithm for real-parameter optimization by using adaptive discretization.

PubMed

Chen, Ying-ping; Chen, Chao-Hong

2010-01-01

An adaptive discretization method, called split-on-demand (SoD), enables estimation of distribution algorithms (EDAs) for discrete variables to solve continuous optimization problems. SoD randomly splits a continuous interval if the number of search points within the interval exceeds a threshold, which is decreased at every iteration. After the split operation, the nonempty intervals are assigned integer codes, and the search points are discretized accordingly. As an example of using SoD with EDAs, the integration of SoD and the extended compact genetic algorithm (ECGA) is presented and numerically examined. In this integration, we adopt a local search mechanism as an optional component of our back end optimization engine. As a result, the proposed framework can be considered as a memetic algorithm, and SoD can potentially be applied to other memetic algorithms. The numerical experiments consist of two parts: (1) a set of benchmark functions on which ECGA with SoD and ECGA with two well-known discretization methods: the fixed-height histogram (FHH) and the fixed-width histogram (FWH) are compared; (2) a real-world application, the economic dispatch problem, on which ECGA with SoD is compared to other methods. The experimental results indicate that SoD is a better discretization method to work with ECGA. Moreover, ECGA with SoD works quite well on the economic dispatch problem and delivers solutions better than the best known results obtained by other methods in existence.

Identification of relevant single-nucleotide polymorphisms in Pneumocystis jirovecii: relationship with clinical data.

PubMed

Esteves, F; Gaspar, J; Marques, T; Leite, R; Antunes, F; Mansinho, K; Matos, O

2010-07-01

Pneumocystis jirovecii is a poorly understood pathogen that causes opportunistic pneumonia (Pneumocystis pneumonia (PcP)) in patients with AIDS. The present study was aimed at correlating genetic differences in P. jirovecii isolates and clinical patient data. A description of genetic diversity in P. jirovecii isolates from human immunodeficiency virus-positive patients, based on the identification of multiple single-nucleotide polymorphisms (SNPs) at five distinct loci encoding mitochondrial large-subunit rRNA (mtLSU rRNA), cytochrome b (CYB), superoxide dismutase (SOD), dihydrofolate reductase (DHFR), and dihydropteroate synthase (DHPS), was achieved using PCR with DNA sequencing and restriction fragment length polymorphism analysis. The statistical analysis revealed several interesting correlations among the four most relevant SNPs (mt85, SOD110, SOD215, and DHFR312) and specific clinical parameters: mt85C was associated with undiagnosed or atypical PcP episodes and favourable follow-up; SOD215C was associated with favourable follow-up; and DHFR312T was associated with PcP cases presenting moderate to high parasite burdens. The genotypes mt85C/SOD215C and SOD110T/SOD215C were found to be associated with less virulent P. jirovecii infections, whereas the genotype SOD110T/SOD215T was found to be related to more virulent PcP episodes. The present work demonstrated that potential P. jirovecii haplotypes may be related to the clinical data and outcome of PcP.

Endotoxin treatment protects rats against ozone-induced lung edema: with evidence for the role of manganese superoxide dismutase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rahman, I.; Massaro, D.

Ozone is a strong oxidizing agent that can cause lung damage and edema. There is evidence that it does so by causing peroxidation of membrane lipids. However, the elevation in lung activity of copper, zinc superoxide dismutase (Cu, ZnSOD), and manganese superoxide dismutase (MnSOD) during exposure to ozone suggests that increased production of superoxide could contribute to lung edema caused by ozone. This latter observation, and preliminary evidence that treatment of rats with endotoxin elevates lung activity of MnSOD without elevation of the activity of Cu, ZnSOD, catalase (CAT), or glutathione peroxidase (GP), led to the present study. We treatedmore » rats with endotoxin, exposed them to different concentrations of ozone, measured lung wet weight to dry weight ratio, thiobarbituric acid-reactive material (TBAR), and assayed lung tissue for Cu, ZnSOD, MnSOD, CAT, and GP activity. Our major findings are, (1) a strongly edemogenic concentration of ozone-lowered MnSOD activity; (2) endotoxin treatment of air-breathing rats did not decrease lipid peroxidation as indicated by the lung concentration of TBAR; (3) induction of increased MnSOD activity in lung by treatment with endotoxin was associated with virtually complete protection against an otherwise edemogenic concentration of ozone, with less lipid peroxidation, and with less loss of weight; and (4) this protection occurred without elevated Cu, ZnSOD, CAT, or GP activity.« less

Comparison of effect of vitamin E-coated dialyzer and oral vitamin E on hemodialysis-induced Cu/Zn-superoxide dismutase.

PubMed

Akiyama, Shinichiro; Inagaki, Masahiro; Tsuji, Mayumi; Gotoh, Hiromichi; Gotoh, Tomomi; Washio, Kazunori; Gotoh, Yoshikazu; Oguchi, Katsuji

2005-01-01

We reported earlier that production of Cu/Zn-superoxide dismutase (SOD) increases markedly in hemodialysis patients but not in non-dialyzed chronic renal failure (CRF) patients. In this study, we compared the antioxidant effects of oral vitamin E supplementation (VE-PO) and vitamin E coating of a dialyzer (VE-BMD) by measuring increased Cu/Zn-SOD in hemodialysis patients. 31 hemodialysis patients were divided into two groups: 16 hemodialysis patients underwent usual dialysis with vitamin E supplementation 600 mg/day while 15 others were dialyzed using vitamin E-coated membrane for 6 months. Total plasma SOD activity was determined by NBT method, plasma Cu/Zn-SOD contents by ELISA and Cu/Zn-SOD mRNA in leukocytes by RT-PCR. VE-PO and VE-BMD showed almost comparable effects on Cu/Zn-SOD contents and its mRNA levels in hemodialysis patients. VE-PO resulted in a progressive decrease of Cu/Zn-SOD content (p < 0.001). A comparable progressive decrease was observed also in VE-BMD (p < 0.0001). Both VE-PO and VE-BMD resulted in a progressive decrease of Cu/Zn-SOD mRNA (p < 0.01), which reached the level of non-dialyzed CRF patients. Copyright (c) 2005 S. Karger AG, Basel.

Large SOD1 aggregates, unlike trimeric SOD1, do not impact cell viability in a model of amyotrophic lateral sclerosis.

PubMed

Zhu, Cheng; Beck, Matthew V; Griffith, Jack D; Deshmukh, Mohanish; Dokholyan, Nikolay V

2018-05-01

Aberrant accumulation of misfolded Cu, Zn superoxide dismutase (SOD1) is a hallmark of SOD1-associated amyotrophic lateral sclerosis (ALS), an invariably fatal neurodegenerative disease. While recent discovery of nonnative trimeric SOD1-associated neurotoxicity has suggested a potential pathway for motor neuron impairment, it is yet unknown whether large, insoluble aggregates are cytotoxic. Here we designed SOD1 mutations that specifically stabilize either the fibrillar form or the trimeric state of SOD1. The designed mutants display elevated populations of fibrils or trimers correspondingly, as demonstrated by gel filtration chromatography and electron microscopy. The trimer-stabilizing mutant, G147P, promoted cell death, even more potently in comparison with the aggressive ALS-associated mutants A4V and G93A. In contrast, the fibril-stabilizing mutants, N53I and D101I, positively impacted the survival of motor neuron-like cells. Hence, we conclude the SOD1 oligomer and not the mature form of aggregated fibril is critical for the neurotoxic effects in the model of ALS. The formation of large aggregates is in competition with trimer formation, suggesting that aggregation may be a protective mechanism against formation of toxic oligomeric intermediates.

Protective effect of [6]-gingerol on the ethanol-induced teratogenesis of cultured mouse embryos.

PubMed

Yon, Jung-Min; Baek, In-Jeoung; Lee, Se-Ra; Kim, Mi-Ra; Hong, Jin Tae; Yong, Hwanyul; Lee, Beom Jun; Yun, Young Won; Nam, Sang-Yoon

2012-01-01

Excessive ethanol consumption during pregnancy causes fetal alcohol syndrome. We investigated the effect of [6]-gingerol on ethanol-induced embryotoxicity using a whole embryo culture system. The morphological changes of embryos and the gene expression patterns of the antioxidant enzymes cytosolic glutathione peroxidase (cGPx), cytoplasmic Cu/Zn superoxide dismutase (SOD1), and Mn-SOD (SOD2), and SOD activity were examined in the cultured mouse embryos exposed to ethanol (5 μL/3 mL) and/or [6]-gingerol (1×10(-8) or 1×10(-7) μg/mL) for 2 days. In ethanol-exposed embryos, the standard morphological score of embryos was significantly decreased compared with those of the control (vehicle) group. However, cotreatment of embryos with [6]-gingerol and ethanol significantly improved all of the developmental parameters except crownrump length and head length, compared with those of the ethanol alone group. The mRNA expression levels of cGPx and SOD2, not SOD1, were decreased consistently, SOD activity were significantly decreased compared with the control group. However, the decreases in mRNA levels of antioxidant enzymes and SOD activity were significantly restored to the control levels by [6]-gingerol supplement. These results indicate that [6]-gingerol has a protective effect against ethanol-induced teratogenicity during mouse embryogenesis.

Consequences of MnSOD interactions with nitric oxide: nitric oxide dismutation and the generation of peroxynitrite and hydrogen peroxide.

PubMed

Filipović, Milos R; Stanić, Dragana; Raicević, Smiljana; Spasić, Mihajlo; Niketić, Vesna

2007-01-01

The present study demonstrates that manganese superoxide dismutase (MnSOD) (Escherichia coli), binds nitric oxide (*NO) and stimulates its decay under both anaerobic and aerobic conditions. The results indicate that previously observed MnSOD-catalyzed *NO disproportionation (dismutation) into nitrosonium (NO+) and nitroxyl (NO-) species under anaerobic conditions is also operative in the presence of molecular oxygen. Upon sustained aerobic exposure to *NO, MnSOD-derived NO- species initiate the formation of peroxynitrite (ONOO-) leading to enzyme tyrosine nitration, oxidation and (partial) inactivation. The results suggest that both ONOO- decomposition and ONOO(-)-dependent tyrosine residue nitration and oxidation are enhanced by metal centre-mediated catalysis. We show that the generation of ONOO- is accompanied by the formation of substantial amounts of H2O2. MnSOD is a critical mitochondrial antioxidant enzyme, which has been found to undergo tyrosine nitration and inactivation in various pathologies associated with the overproduction of *NO. The results of the present study can account for the molecular specificity of MnSOD nitration in vivo. The interaction of *NO with MnSOD may represent a novel mechanism by which MnSOD protects the cell from deleterious effects associated with overproduction of *NO.

Accumulation of misfolded SOD1 in dorsal root ganglion degenerating proprioceptive sensory neurons of transgenic mice with amyotrophic lateral sclerosis.

PubMed

Sábado, Javier; Casanovas, Anna; Tarabal, Olga; Hereu, Marta; Piedrafita, Lídia; Calderó, Jordi; Esquerda, Josep E

2014-01-01

Amyotrophic lateral sclerosis (ALS) is an adult-onset progressive neurodegenerative disease affecting upper and lower motoneurons (MNs). Although the motor phenotype is a hallmark for ALS, there is increasing evidence that systems other than the efferent MN system can be involved. Mutations of superoxide dismutase 1 (SOD1) gene cause a proportion of familial forms of this disease. Misfolding and aggregation of mutant SOD1 exert neurotoxicity in a noncell autonomous manner, as evidenced in studies using transgenic mouse models. Here, we used the SOD1(G93A) mouse model for ALS to detect, by means of conformational-specific anti-SOD1 antibodies, whether misfolded SOD1-mediated neurotoxicity extended to neuronal types other than MNs. We report that large dorsal root ganglion (DRG) proprioceptive neurons accumulate misfolded SOD1 and suffer a degenerative process involving the inflammatory recruitment of macrophagic cells. Degenerating sensory axons were also detected in association with activated microglial cells in the spinal cord dorsal horn of diseased animals. As large proprioceptive DRG neurons project monosynaptically to ventral horn MNs, we hypothesise that a prion-like mechanism may be responsible for the transsynaptic propagation of SOD1 misfolding from ventral horn MNs to DRG sensory neurons.

Use of Cu/Zn-superoxide dismutase tool for biomonitoring marine environment pollution in the Persian Gulf and the Gulf of Oman.

PubMed

Zeinali, Farrokhzad; Homaei, Ahmad; Kamrani, Ehsan; Patel, Seema

2018-04-30

Superoxide dismutase (SOD) is the pivotal antioxidant enzyme that defends organisms against the oxidative stresses of superoxide radicals. In this experimental study, purification of SOD from the leaves of Avicennia marina (grey mangrove or white mangrove) from the family Acanthaceae, located in Sirik mangrove forest on the shore of the Gulf of Oman was performed, for the intended characterization of SOD. The Sirik AmSOD (A. marina SOD) expressed optimum activity in the pH range of 6-9 with the maximum activity at pH 8. The optimal temperature for Sirik AmSOD activity was 70°C. Comparison of the pH and temperature optima in two regions (the Persian Gulf and the Gulf of Oman) showed significant differences with P<0.05. The SOD from the Persian Gulf was more resistant against the environmental stressors, because of the biochemical adaption to this environment, which is harsher. The evidence from these results suggests that AmSOD has different characteristics in each place, and mangroves undergo different adaptations and require different protections. The results of the enzymatic research can be useful for ecological management of organisms. Copyright © 2018 Elsevier Inc. All rights reserved.

Zymogram profiling of superoxide dismutase and catalase activities allows Saccharomyces and non-Saccharomyces species differentiation and correlates to their fermentation performance.

PubMed

Gamero-Sandemetrio, Esther; Gómez-Pastor, Rocío; Matallana, Emilia

2013-05-01

Aerobic organisms have devised several enzymatic and non-enzymatic antioxidant defenses to deal with reactive oxygen species (ROS) produced by cellular metabolism. To combat such stress, cells induce ROS scavenging enzymes such as catalase, peroxidase, superoxide dismutase (SOD) and glutathione reductase. In the present research, we have used a double staining technique of SOD and catalase enzymes in the same polyacrylamide gel to analyze the different antioxidant enzymatic activities and protein isoforms present in Saccharomyces and non-Saccharomyces yeast species. Moreover, we used a technique to differentially detect Sod1p and Sod2p on gel by immersion in NaCN, which specifically inhibits the Sod1p isoform. We observed unique SOD and catalase zymogram profiles for all the analyzed yeasts and we propose this technique as a new approach for Saccharomyces and non-Saccharomyces yeast strains differentiation. In addition, we observed functional correlations between SOD and catalase enzyme activities, accumulation of essential metabolites, such as glutathione and trehalose, and the fermentative performance of different yeasts strains with industrial relevance.

Effect of intradermal human recombinant copper-zinc superoxide dismutase on random pattern flaps in rats.

PubMed

Schein, Ophir; Westreich, Melvyn; Shalom, Avshalom

2013-09-01

Studies have focused on enhancing flap viability using superoxide dismutase (SOD), but only a few used SOD from human origin, and most gave the compound systemically. We evaluated the ability of SOD to improve random skin flap survival using human recombinant copper-zinc superoxide dismutase (Hr-CuZnSOD) in variable doses, injected intradermally into the flap. Seventy male Sprague Dawley rats were randomly assigned into 4 groups. Cephalic random pattern flaps were elevated on their backs and intradermal injections of different dosages of Hr-CuZnSOD were given 15 minutes before surgery. Flap survival was evaluated by fluorescein fluorescence. Analysis of variance (ANOVA) and t test statistical analyses were performed. Flap survival in all treated groups was significantly better than in the controls. The beneficial effect of HR-CuZnSOD on flap survival is attained when it is given intradermally into the flap tissue. Theoretically, Hr-CuZnSOD delivered with local anesthetics used in flap elevation may be a valuable clinical tool. Copyright © 2012 Wiley Periodicals, Inc.

Trichloroethylene exposure aggravates behavioral abnormalities in mice that are deficient in superoxide dismutase.

PubMed

Otsuki, Noriyuki; Homma, Takujiro; Fujiwara, Hiroki; Kaneko, Kenya; Hozumi, Yasukazu; Shichiri, Mototada; Takashima, Mizuki; Ito, Junitsu; Konno, Tasuku; Kurahashi, Toshihiro; Yoshida, Yasukazu; Goto, Kaoru; Fujii, Satoshi; Fujii, Junichi

2016-08-01

Trichloroethylene (TCE) has been implicated as a causative agent for Parkinson's disease (PD). The administration of TCE to rodents induces neurotoxicity associated with dopaminergic neuron death, and evidence suggests that oxidative stress as a major player in the progression of PD. Here we report on TCE-induced behavioral abnormality in mice that are deficient in superoxide dismutase 1 (SOD1). Wild-type (WT) and SOD1-deficient (Sod1(-/-)) mice were intraperitoneally administered TCE (500 mg/kg) over a period of 4 weeks. Although the TCE-administrated Sod1(-/-) mice showed marked abnormal motor behavior, no significant differences were observed among the experimental groups by biochemical and histopathological analyses. However, treating mouse neuroblastoma-derived NB2a cells with TCE resulted in the down regulation of the SOD1 protein and elevated oxidative stress under conditions where SOD1 production was suppressed. Taken together, these data indicate that SOD1 plays a pivotal role in protecting motor neuron function against TCE toxicity. Copyright © 2016 Elsevier Inc. All rights reserved.

Structural and biophysical properties of metal-free pathogenic SOD1 mutants A4V and G93A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galaleldeen, Ahmad; Strange, Richard W.; Whitson, Lisa J.

2010-07-19

Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurodegenerative disease characterized by the destruction of motor neurons in the spinal cord and brain. A subset of ALS cases are linked to dominant mutations in copper-zinc superoxide dismutase (SOD1). The pathogenic SOD1 variants A4V and G93A have been the foci of multiple studies aimed at understanding the molecular basis for SOD1-linked ALS. The A4V variant is responsible for the majority of familial ALS cases in North America, causing rapidly progressing paralysis once symptoms begin and the G93A SOD1 variant is overexpressed in often studied murine models of the disease. Here wemore » report the three-dimensional structures of metal-free A4V and of metal-bound and metal-free G93A SOD1. In the metal-free structures, the metal-binding loop elements are observed to be severely disordered, suggesting that these variants may share mechanisms of aggregation proposed previously for other pathogenic SOD1 proteins.« less

Superoxide Dismutase in Ripening Fruits

PubMed Central

Baker, James Earl

1976-01-01

The levels of superoxide dismutase (SOD) activity in extracts of preclimacteric apple, banana, avocado, and tomato fruits were not greatly different than in extracts of postclimacteric fruits. The results indicate that no major quantitative change in SOD occurs in fruits with or preceding the onset of senescence. Tomato fruit SOD was studied in more detail, and was found largely in the soluble fraction, and to a lesser extent in the mitochondrial and plastid fractions. The soluble fraction was purified by ammonium sulfate fractionation, column chromatography, and isoelectric focusing. Isoelectric focusing separated SOD from contaminating peroxidases. The purified tomato SOD showed an apparent molecular weight of 31,500 determined by gel filtration. Polyacrylamide gel electrophoresis of this preparation indicated two SOD components corresponding to two protein bands, one of which stained more intensely than the other. The purified tomato enzyme was inhibited 90% by 1 mm KCN. PMID:16659735

[The protective effect of bone marrow mesenchymal stem cells carrying antioxidant gene superoxide dismutase on paraquat lung injury in mice].

PubMed

Liu, Hong; Ding, Yingwei; Hou, Yuehui; Zhao, Guangju; Lu, Yang; Chen, Xiao; Cai, Qiqi; Hong, Guangliang; Qiu, Qiaomeng; Lu, Zhongqiu

2016-01-01

To explore the possible mechanism and protective effect of BMSCs (bone mesenchymal stem cells) carrying superoxide dismutase (SOD) gene on mice with paraquat-induced acute lung injury. To establish the cell line of BMSCs bringing SOD gene, lentiviral vector bringing SOD gene was built and co-cultured with BMSCs. A total of 100 BALB/c mice were randomly divided into five groups, namely Control group, poisoning group (PQ group) , BMSCs therapy group (BMSC group) , BMSCs-Cherry therapy group (BMSC-Cherry group) , BMSCs-SOD therapy group (BMSC-SOD group) . PQ poisoning model was produced by stomach lavaged once with 1 ml of 25 mg/kg PQ solution, and the equal volume of normal saline (NS) was given to Control group mice instead of PQ. The corresponding BMSCs therapy cell lines were delivered to mice through the tail vein of mice 4h after PQ treatment.Five mice of each group were sacrificed 3 d, 7 d, 14 d and 21 days after corresponding BMSCs therapy cell lines administration, and lung tissues of mice were taken to make sections for histological analysis. The serum levels of glutathione (GSH) , malondialdehyde (MDA) , SOD, and the levels of transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α) in lung tissue were determined. The level of SOD was assayed by Westen-blot. Compared with Control group, the early (3 days) levels of SOD protein in lung tissue of PQ group obviously decreased, and the late (21 days) levels of SOD obviously increased, while in therapy groups, that was higher than that in PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) . Compared with Control group, the levels of plasma GSH and SOD of PQ group and each therapy group wae significantly lower than those in Control group, while in therapy groups, those were higher than those of PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) .Compared with Control group, the level of plasma MDA, TNF-α and TGF-β in PQ group and therapy groups were significantly higher, while in therapy groups, that was lower than that in PQ group, and the BMSCs-SOD group showed most obvious (all P<0.05) . Lung biopsy showed that, the degree of lung tissue damage in each therapy group obviously reduced. SOD is the key factor of the removal of reactive oxygen species (ROS) in cells, that can obviously inhibit the oxidative stress damage and the apoptosis induced by PQ, thus significantly increasing alveolar epithelial cell ability to fight outside harmful environment.

Hyperglycemia-induced diaphragm weakness is mediated by oxidative stress

PubMed Central

2014-01-01

Introduction A major consequence of ICU-acquired weakness (ICUAW) is diaphragm weakness, which prolongs the duration of mechanical ventilation. Hyperglycemia (HG) is a risk factor for ICUAW. However, the mechanisms underlying HG-induced respiratory muscle weakness are not known. Excessive reactive oxygen species (ROS) injure multiple tissues during HG, but only one study suggests that excessive ROS generation may be linked to HG-induced diaphragm weakness. We hypothesized that HG-induced diaphragm dysfunction is mediated by excessive superoxide generation and that administration of a specific superoxide scavenger, polyethylene glycol superoxide dismutase (PEG-SOD), would ameliorate these effects. Methods HG was induced in rats using streptozotocin (60 mg/kg intravenously) and the following groups assessed at two weeks: controls, HG, HG + PEG-SOD (2,000U/kg/d intraperitoneally for seven days), and HG + denatured (dn)PEG-SOD (2000U/kg/d intraperitoneally for seven days). PEG-SOD and dnPEG-SOD were administered on day 8, we measured diaphragm specific force generation in muscle strips, force-pCa relationships in single permeabilized fibers, contractile protein content and indices of oxidative stress. Results HG reduced diaphragm specific force generation, altered single fiber force-pCa relationships, depleted troponin T, and increased oxidative stress. PEG-SOD prevented HG-induced reductions in diaphragm specific force generation (for example 80 Hz force was 26.4 ± 0.9, 15.4 ± 0.9, 24.0 ± 1.5 and 14.9 ± 0.9 N/cm2 for control, HG, HG + PEG-SOD, and HG + dnPEG-SOD groups, respectively, P <0.001). PEG-SOD also restored HG-induced reductions in diaphragm single fiber force generation (for example, Fmax was 182.9 ± 1.8, 85.7 ± 2.0, 148.6 ± 2.4 and 90.9 ± 1.5 kPa in control, HG, HG + PEG-SOD, and HG + dnPEG-SOD groups, respectively, P <0.001). HG-induced troponin T depletion, protein nitrotyrosine formation, and carbonyl modifications were largely prevented by PEG-SOD. Conclusions HG-induced reductions in diaphragm force generation occur largely at the level of the contractile proteins, are associated with depletion of troponin T and increased indices of oxidative stress, findings not previously reported. Importantly, administration of PEG-SOD largely ablated these derangements, indicating that superoxide generation plays a major role in hyperglycemia-induced diaphragm dysfunction. This new mechanistic information could explain how HG alters diaphragm function during critical illness. PMID:24886999

Effect of CCS on the Accumulation of FALS SOD1 Mutant-containing Aggregates and on Mitochondrial Translocation of SOD1 Mutants: Implication of a Free Radical Hypothesis

PubMed Central

Kim, Ha Kun; Chung, Youn Wook; Chock, P. Boon; Yim, Moon B.

2011-01-01

Missense mutations of SOD1 are linked to familial amyotrophic lateral sclerosis (FALS) through a yet-to-be identified toxic-gain-of-function. One of the proposed mechanisms involves enhanced aggregate formation. However, a recent study showed that dual transgenic mice overexpressing both G93A and CCS copper chaperone (G93A/CCS) exhibit no SOD1-positive aggregates yet show accelerated FALS symptoms with enhanced mitochondrial pathology compared to G93A mice. Using a dicistronic mRNA to simultaneously generate hSOD1 mutants, G93A, A4V and G85R, and hCCS in AAV293 cells, we revealed: (i) CCS is degraded primarily via a macroautophagy pathway. It forms a stable heterodimer with inactive G85R, and via its novel copper chaperone-independent molecular chaperone activity facilitates G85R degradation via a macroautophagy-mediated pathway. For active G93A and A4V, CCS catalyzes their maturation to form active and soluble homodimers. (ii) CCS reduces, under non-oxidative conditions, yet facilitates in the presence of H2O2, mitochondrial translocation of inactive SOD1 mutants. These results, together with previous reports showing FALS SOD1 mutants enhanced free radical-generating activity, provide a mechanistic explanation for the observations with G93A/CCS dual transgenic mice and suggest that free radical generation by FALS SOD1, enhanced by CCS, may, in part, be responsible for the FALS SOD1 mutant-linked aggregation, mitochondrial translocation, and degradation. PMID:21354101

Functional characterization and expression of a cytosolic iron-superoxide dismutase from cowpea root nodules.

PubMed

Moran, Jose F; James, Euan K; Rubio, Maria C; Sarath, Gautam; Klucas, Robert V; Becana, Manuel

2003-10-01

An iron-superoxide dismutase (FeSOD) with an unusual subcellular localization, VuFeSOD, has been purified from cowpea (Vigna unguiculata) nodules and leaves. The enzyme has two identical subunits of 27 kD that are not covalently bound. Comparison of its N-terminal sequence (NVAGINLL) with the cDNA-derived amino acid sequence showed that VuFeSOD is synthesized as a precursor with seven additional amino acids. The mature protein was overexpressed in Escherichia coli, and the recombinant enzyme was used to generate a polyclonal monospecific antibody. Phylogenetic and immunological data demonstrate that there are at least two types of FeSODs in plants. An enzyme homologous to VuFeSOD is present in soybean (Glycine max) and common bean (Phaseolus vulgaris) nodules but not in alfalfa (Medicago sativa) and pea (Pisum sativum) nodules. The latter two species also contain FeSODs in the leaves and nodules, but the enzymes are presumably localized to the chloroplasts and plastids. In contrast, immunoblots of the soluble nodule fraction and immunoelectron microscopy of cryo-processed nodule sections demonstrate that VuFeSOD is localized to the cytosol. Immunoblot analysis showed that the content of VuFeSOD protein increases in senescent nodules with active leghemoglobin degradation, suggesting a direct or indirect (free radical-mediated) role of the released Fe in enzyme induction. Therefore, contrary to the widely held view, FeSODs in plants are not restricted to the chloroplasts and may become an important defensive mechanism against the oxidative stress associated with senescence.

Adaptation to chronic MG132 reduces oxidative toxicity by a CuZnSOD-dependent mechanism

PubMed Central

Leak, Rehana K.; Zigmond, Michael J.; Liou, Anthony K. F.

2010-01-01

To study whether and how cells adapt to chronic cellular stress, we exposed PC12 cells to the proteasome inhibitor MG132 (0.1 μM) for 2 weeks and longer. This treatment reduced chymotrypsin-like proteasome activity by 47% and was associated with protection against both 6-hydroxydopamine (6-OHDA, 100 μM) and higher dose MG132 (40 μM). Protection developed slowly over the course of the first 2 weeks of exposure and was chronic thereafter. There was no change in total glutathione levels after MG132. Buthionine sulfoximine (100 μM) reduced glutathione levels by 60%, but exacerbated 6-OHDA toxicity to the same extent in both MG132-treated and control cells and failed to reduce MG132-induced protection. Chronic MG132 resulted in elevated antioxidant proteins CuZn superoxide dismutase (SOD, +55%), MnSOD (+21%), and catalase (+15%), as well as chaperone heat shock protein 70 (+42%). Examination of SOD enzyme activity revealed higher levels of CuZnSOD (+40%), with no change in MnSOD. We further assessed the mechanism of protection by reducing CuZnSOD levels with two independent siRNA sequences, both of which successfully attenuated protection against 6-OHDA. Previous reports suggested that artificial overexpression of CuZnSOD in dopaminergic cells is protective. Our data complement such observations, revealing that dopaminergic cells are also able to use endogenous CuZnSOD in self-defensive adaptations to chronic stress, and that they can even do so in the face of extensive glutathione loss. PMID:18466318

Calcium Ions Promote Superoxide Dismutase 1 (SOD1) Aggregation into Non-fibrillar Amyloid

PubMed Central

Leal, Sónia S.; Cardoso, Isabel; Valentine, Joan S.; Gomes, Cláudio M.

2013-01-01

Imbalance in metal ion homeostasis is a hallmark in neurodegenerative conditions involving protein deposition, and amyotrophic lateral sclerosis (ALS) is no exception. In particular, Ca2+ dysregulation has been shown to correlate with superoxide dismutase-1 (SOD1) aggregation in a cellular model of ALS. Here we present evidence that SOD1 aggregation is enhanced and modulated by Ca2+. We show that at physiological pH, Ca2+ induces conformational changes that increase SOD1 β-sheet content, as probed by far UV CD and attenuated total reflectance-FTIR, and enhances SOD1 hydrophobicity, as probed by ANS fluorescence emission. Moreover, dynamic light scattering analysis showed that Ca2+ boosts the onset of SOD1 aggregation. In agreement, Ca2+ decreases SOD1 critical concentration and nucleation time during aggregation kinetics, as evidenced by thioflavin T fluorescence emission. Attenuated total reflectance FTIR analysis showed that Ca2+ induced aggregates consisting preferentially of antiparallel β-sheets, thus suggesting a modulation effect on the aggregation pathway. Transmission electron microscopy and analysis with conformational anti-fibril and anti-oligomer antibodies showed that oligomers and amyloidogenic aggregates constitute the prevalent morphology of Ca2+-induced aggregates, thus indicating that Ca2+ diverts SOD1 aggregation from fibrils toward amorphous aggregates. Interestingly, the same heterogeneity of conformations is found in ALS-derived protein inclusions. We thus hypothesize that transient variations and dysregulation of cellular Ca2+ levels contribute to the formation of SOD1 aggregates in ALS patients. In this scenario, Ca2+ may be considered as a pathogenic effector in the formation of ALS proteinaceous inclusions. PMID:23861388

Effects of Altered Levels of Extracellular Superoxide Dismutase and Irradiation on Hippocampal Neurogenesis in Female Mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zou, Yani; Leu, David; Palo Alto Institute of Research and Education, Palo Alto, California

Purpose: Altered levels of extracellular superoxide dismutase (EC-SOD) and cranial irradiation have been shown to affect hippocampal neurogenesis. However, previous studies were only conducted in male mice, and it was not clear if there was a difference between males and females. Therefore, female mice were studied and the results compared with those generated in male mice from an earlier study. Methods and Materials: Female wild-type, EC-SOD-null (KO), and EC-SOD bigenic mice with neuronal-specific expression of EC-SOD (OE) were subjected to a single dose of 5-Gy gamma rays to the head at 8 weeks of age. Progenitor cell proliferation, differentiation, andmore » long-term survival of newborn neurons were determined. Results: Similar to results from male mice, EC-SOD deficiency and irradiation both resulted in significant reductions in mature newborn neurons in female mice. EC-SOD deficiency reduced long-term survival of newborn neurons whereas irradiation reduced progenitor cell proliferation. Overexpression of EC-SOD corrected the negative impacts from EC-SOD deficiency and irradiation and normalized the production of newborn neurons in OE mice. Expression of neurotrophic factors brain-derived neurotrophic factor and neurotrophin-3 were significantly reduced by irradiation in wild-type mice, but the levels were not changed in KO and OE mice even though both cohorts started out with a lower baseline level. Conclusion: In terms of hippocampal neurogenesis, EC-SOD deficiency and irradiation have the same overall effects in males and females at the age the studies were conducted.« less

Cytoplasmic Copper Detoxification in Salmonella Can Contribute to SodC Metalation but Is Dispensable during Systemic Infection

PubMed Central

Fenlon, Luke A.

2017-01-01

ABSTRACT Salmonella enterica serovar Typhimurium is a leading cause of foodborne disease worldwide. Severe infections result from the ability of S. Typhimurium to survive within host immune cells, despite being exposed to various host antimicrobial factors. SodCI, a copper-zinc-cofactored superoxide dismutase, is required to defend against phagocytic superoxide. SodCII, an additional periplasmic superoxide dismutase, although produced during infection, does not function in the host. Previous studies suggested that CueP, a periplasmic copper binding protein, facilitates acquisition of copper by SodCII. CopA and GolT, both inner membrane ATPases that pump copper from the cytoplasm to the periplasm, are a source of copper for CueP. Using in vitro SOD assays, we found that SodCI can also utilize CueP to acquire copper. However, both SodCI and SodCII have a significant fraction of activity independent of CueP and cytoplasmic copper export. We utilized a series of mouse competition assays to address the in vivo role of CueP-mediated SodC activation. A copA golT cueP triple mutant was equally as competitive as the wild type, suggesting that sufficient SodCI is active to defend against phagocytic superoxide independent of CueP and cytoplasmic copper export. We also confirmed that a strain containing a modified SodCII, which is capable of complementing a sodCI deletion, was fully virulent in a copA golT cueP background competed against the wild type. These competitions also address the potential impact of cytoplasmic copper toxicity within the phagosome. Our data suggest that Salmonella does not encounter inhibitory concentrations of copper during systemic infection. IMPORTANCE Salmonella is a leading cause of gastrointestinal disease worldwide. In severe cases, Salmonella can cause life-threatening systemic infections, particularly in very young children, the elderly, or people who are immunocompromised. To cause disease, Salmonella must survive the hostile environment inside host immune cells, a location in which most bacteria are killed. Our work examines how one particular metal, copper, is acquired by Salmonella to activate a protein important for survival within immune cells. At high levels, copper itself can inhibit Salmonella. Using a strain of Salmonella that cannot detoxify intracellular copper, we also addressed the in vivo role of copper as an antimicrobial agent. PMID:28924031

Cytoplasmic Copper Detoxification in Salmonella Can Contribute to SodC Metalation but Is Dispensable during Systemic Infection.

PubMed

Fenlon, Luke A; Slauch, James M

2017-12-15

Salmonella enterica serovar Typhimurium is a leading cause of foodborne disease worldwide. Severe infections result from the ability of S Typhimurium to survive within host immune cells, despite being exposed to various host antimicrobial factors. SodCI, a copper-zinc-cofactored superoxide dismutase, is required to defend against phagocytic superoxide. SodCII, an additional periplasmic superoxide dismutase, although produced during infection, does not function in the host. Previous studies suggested that CueP, a periplasmic copper binding protein, facilitates acquisition of copper by SodCII. CopA and GolT, both inner membrane ATPases that pump copper from the cytoplasm to the periplasm, are a source of copper for CueP. Using in vitro SOD assays, we found that SodCI can also utilize CueP to acquire copper. However, both SodCI and SodCII have a significant fraction of activity independent of CueP and cytoplasmic copper export. We utilized a series of mouse competition assays to address the in vivo role of CueP-mediated SodC activation. A copA golT cueP triple mutant was equally as competitive as the wild type, suggesting that sufficient SodCI is active to defend against phagocytic superoxide independent of CueP and cytoplasmic copper export. We also confirmed that a strain containing a modified SodCII, which is capable of complementing a sodCI deletion, was fully virulent in a copA golT cueP background competed against the wild type. These competitions also address the potential impact of cytoplasmic copper toxicity within the phagosome. Our data suggest that Salmonella does not encounter inhibitory concentrations of copper during systemic infection. IMPORTANCE Salmonella is a leading cause of gastrointestinal disease worldwide. In severe cases, Salmonella can cause life-threatening systemic infections, particularly in very young children, the elderly, or people who are immunocompromised. To cause disease, Salmonella must survive the hostile environment inside host immune cells, a location in which most bacteria are killed. Our work examines how one particular metal, copper, is acquired by Salmonella to activate a protein important for survival within immune cells. At high levels, copper itself can inhibit Salmonella Using a strain of Salmonella that cannot detoxify intracellular copper, we also addressed the in vivo role of copper as an antimicrobial agent. Copyright © 2017 American Society for Microbiology.

Reactive oxygen species on bone mineral density and mechanics in Cu,Zn superoxide dismutase (Sod1) knockout mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smietana, Michael J.; Arruda, Ellen M.; Mechanical Engineering, University of Michigan, 2250 GG Brown, 2350 Hayward, Ann Arbor, MI 48109

Research highlights: {yields} Reactive oxygen species (ROS) are considered to be a factor in the onset of a number of age-associated conditions, including loss of BMD. {yields} Cu,Zn-superoxide dismutase (Sod1) deficient mice have increased ROS, reduced bone mineral density, decreased bending stiffness, and decreased strength compared to WT controls. {yields} Increased ROS caused by the deficiency of Sod1, may be responsible for the changes in BMD and bone mechanics and therefore represent an appropriate model for studying mechanisms of age-associated bone loss. -- Abstract: Reactive oxygen species (ROS) play a role in a number of degenerative conditions including osteoporosis. Micemore » deficient in Cu,Zn-superoxide dismutase (Sod1) (Sod1{sup -/-} mice) have elevated oxidative stress and decreased muscle mass and strength compared to wild-type mice (WT) and appear to have an accelerated muscular aging phenotype. Thus, Sod1{sup -/-} mice may be a good model for evaluating the effects of free radical generation on diseases associated with aging. In this experiment, we tested the hypothesis that the structural integrity of bone as measured by bending stiffness (EI; N/mm{sup 2}) and strength (MPa) is diminished in Sod1{sup -/-} compared to WT mice. Femurs were obtained from male and female WT and Sod1{sup -/-} mice at 8 months of age and three-point bending tests were used to determine bending stiffness and strength. Bones were also analyzed for bone mineral density (BMD; mg/cc) using micro-computed tomography. Femurs were approximately equal in length across all groups, and there were no significant differences in BMD or EI with respect to gender in either genotype. Although male and female mice demonstrated similar properties within each genotype, Sod1{sup -/-} mice exhibited lower BMD and EI of femurs from both males and females compared with gender matched WT mice. Strength of femurs was also lower in Sod1{sup -/-} mice compared to WT as well as between genders. These data indicate that increased oxidative stress, due to the deficiency of Sod1 is associated with decreased bone stiffness and strength and Sod1{sup -/-} mice may represent an appropriate model for studying disease processes in aging bone.« less

Effects of fluorine contamination on spin-on dielectric thickness in semiconductor manufacturing

NASA Astrophysics Data System (ADS)

Kim, Hyoung-ryeun; Hong, Soonsang; Kim, Samyoung; Oh, Changyeol; Hwang, Sung Min

2018-03-01

In the recent semiconductor industry, as the device shrinks, spin-on dielectric (SOD) has been adopted as a widely used material because of its excellent gap-fill, efficient throughput on mass production. SOD film must be uniformly thin, homogeneous and free of particle defects because it has been perfectly perserved after chemical-mechanical polishing (CMP) and etching process. Spin coating is one of the most common techniques for applying SOD thin films to substrates. In spin coating process, the film thickness and uniformity are strong function of the solution viscosity, the final spin speed and the surface properties. Especially, airborne molecular contaminants (AMCs), such as HF, HCl and NH3, are known to change to surface wetting characteristics. In this work, we study the SOD film thickness as a function of fluorine contamination on the wafer surface. To examine the effects of airborne molecular contamination, the wafers are directly exposed to HF fume followed by SOD coating. It appears that the film thickness decreases by higher contact angle on the wafer surface due to fluorine contamination. The thickness of the SOD film decreased with increasing fluorine contamination on the wafer surface. It means that the wafer surface with more hydrophobic property generates less hydrogen bonding with the functional group of Si-NH in polysilazane(PSZ)-SOD film. Therefore, the wetting properties of silicon wafer surfaces can be degraded by inorganic contamination in SOD coating process.

Neuronal redox imbalance results in altered energy homeostasis and early postnatal lethality.

PubMed

Maity-Kumar, Gandhari; Thal, Dietmar R; Baumann, Bernd; Scharffetter-Kochanek, Karin; Wirth, Thomas

2015-07-01

Redox imbalance is believed to contribute to the development and progression of several neurodegenerative disorders. Our aim was to develop an animal model that exhibits neuron-specific oxidative stress in the CNS to study the consequences and eventually find clues regarding the pathomechanisms of oxidative insults in neuronal homeostasis. We therefore generated a novel neuron-specific superoxide dismutase 2 (SOD2)-deficient mouse by deleting exon 3 of the SOD2 gene using CamKIIα promoter-driven Cre expression. These neuron-specific SOD2 knockout (SOD2(nko)) mice, although born at normal frequencies, died at the age of 4 weeks with critical growth retardation, severe energy failure, and several neurologic phenotypes. In addition, SOD2(nko) mice exhibited severe neuronal alterations such as reactive astrogliosis, neuronal cell cycle inhibition, and induction of apoptosis. JNK activation and stabilization of p53, as a result of reactive oxygen species accumulation, are most likely the inducers of neuronal apoptosis in SOD2(nko) mice. It is remarkable that hypothalamic regulation of glucose metabolism was affected, which in turn induced necrotic brain lesions in SOD2(nko) mice. Taken together, our findings suggest that exclusive deficiency of SOD2 in neurons results in an impaired central regulation of energy homeostasis that leads to persistent hypoglycemia, hypoglycemia-related neuropathology, and an early lethality of the mutant mice. © FASEB.

Impaired fertilizing ability of superoxide dismutase 1-deficient mouse sperm during in vitro fertilization.

PubMed

Tsunoda, Satoshi; Kawano, Natsuko; Miyado, Kenji; Kimura, Naoko; Fujii, Junichi

2012-11-01

The oxidative modification of gametes by a reactive oxygen species is a major deleterious factor that decreases the successful rate of in vitro fertilization. Superoxide dismutase 1 (SOD1) plays a pivotal role in antioxidation by scavenging the superoxide anion, and its deficiency causes infertility in female mice, but the significance of the enzyme in male mice remains unclear. In the present study, we characterized Sod1(-/-) (Sod1-KO) male reproductive organs and compiled the first report of the impaired fertilizing ability of Sod1-KO sperm in in vitro fertilization. Insemination of wild-type oocytes with Sod1-KO sperm exhibited lower rates of fertility compared with insemination by wild-type sperm. The low fertilizing ability found for Sod1-KO sperm was partially rescued by reductant 2-mercaptoethanol, which suggested the oxidative modification of sperm components. The numbers of motile and progressive sperm decreased during the in vitro fertilization process, and a decline in ATP content and elevation in lipid peroxidation occurred in the Sod1-KO sperm in an incubation time-dependent manner. Tyrosine phosphorylation, which is a hallmark for sperm capacitation, was also impaired in the Sod1-KO sperm. These results collectively suggest that machinery involved in sperm capacitation and motility are vulnerable to oxidative damage during the in vitro fertilization process, which could increase the rate of inefficient fertilization.

The modulation of extracellular superoxide dismutase in the specifically enhanced cellular immune response against secondary challenge of Vibrio splendidus in Pacific oyster (Crassostrea gigas).

PubMed

Liu, Conghui; Zhang, Tao; Wang, Lingling; Wang, Mengqiang; Wang, Weilin; Jia, Zhihao; Jiang, Shuai; Song, Linsheng

2016-10-01

Extracellular superoxide dismutase (EcSOD) is a copper-containing glycoprotein playing an important role in antioxidant defense of living cells exposed to oxidative stress, and also participating in microorganism internalization and cell adhesion in invertebrates. EcSOD from oyster (designated CgEcSOD) had been previously reported to bind lipopolysaccharides (LPS) and act as a bridge molecule in Vibrio splendidus internalization. Its mRNA expression pattern, PAMP binding spectrum and microorganism binding capability were examined in the present study. The mRNA expression of CgEcSOD in hemocytes was significantly up-regulated at the initial phase and decreased sharply at 48 h post V. splendidus stimulation. The recombinant CgEcSOD protein (rCgEcSOD) could bind LPS, PGN and poly (I:C), as well as various microorganisms including Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Vibrio anguillarum, V. splendidus, Pastoris pastoris and Yarrowia lipolytica at the presence of divalent metal ions Cu(2+). After the secondary V. splendidus stimulation, the mRNA and protein of CgEcSOD were both down-regulated significantly. The results collectively indicated that CgEcSOD could not only function in the immune recognition, but also might contribute to the immune priming of oyster by inhibiting the foreign microbe invasion through a specific down-regulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enhanced tethered-flight duration and locomotor activity by overexpression of the human gene SOD1 in Drosophila motorneurons.

PubMed

Petrosyan, Agavni; Hsieh, I-Hui; Phillips, John P; Saberi, Kourosh

2015-03-01

Mutation of the human gene superoxide dismutase (hSOD1) is associated with the fatal neurodegenerative disease familial amyotrophic lateral sclerosis (Lou Gehrig's disease). Selective overexpression of hSOD1 in Drosophila motorneurons increases lifespan to 140% of normal. The current study was designed to determine resistance to lifespan decline and failure of sensorimotor functions by overexpressing hSOD1 in Drosophila's motorneurons. First, we measured the ability to maintain continuous flight and wingbeat frequency (WBF) as a function of age (5 to 50 days). Flies overexpressing hSOD1 under the D42-GAL4 activator were able to sustain flight significantly longer than controls, with the largest effect observed in the middle stages of life. The hSOD1-expressed line also had, on average, slower wingbeat frequencies in late, but not early life relative to age-matched controls. Second, we examined locomotor (exploratory walking) behavior in late life when flies had lost the ability to fly (age ≥ 60 d). hSOD1-expressed flies showed significantly more robust walking activity relative to controls. Findings show patterns of functional decline dissimilar to those reported for other life-extended lines, and suggest that the hSOD1 gene not only delays death but enhances sensorimotor abilities critical to survival even in late life.

Irradiated esophageal cells are protected from radiation-induced recombination by MnSOD gene therapy.

PubMed

Niu, Yunyun; Wang, Hong; Wiktor-Brown, Dominika; Rugo, Rebecca; Shen, Hongmei; Huq, M Saiful; Engelward, Bevin; Epperly, Michael; Greenberger, Joel S

2010-04-01

Radiation-induced DNA damage is a precursor to mutagenesis and cytotoxicity. During radiotherapy, exposure of healthy tissues can lead to severe side effects. We explored the potential of mitochondrial SOD (MnSOD) gene therapy to protect esophageal, pancreatic and bone marrow cells from radiation-induced genomic instability. Specifically, we measured the frequency of homologous recombination (HR) at an integrated transgene in the Fluorescent Yellow Direct Repeat (FYDR) mice, in which an HR event can give rise to a fluorescent signal. Mitochondrial SOD plasmid/liposome complex (MnSOD-PL) was administered to esophageal cells 24 h prior to 29 Gy upper-body irradiation. Single cell suspensions from FYDR, positive control FYDR-REC, and negative control C57BL/6NHsd (wild-type) mouse esophagus, pancreas and bone marrow were evaluated by flow cytometry. Radiation induced a statistically significant increase in HR 7 days after irradiation compared to unirradiated FYDR mice. MnSOD-PL significantly reduced the induction of HR by radiation at day 7 and also reduced the level of HR in the pancreas. Irradiation of the femur and tibial marrow with 8 Gy also induced a significant increase in HR at 7 days. Radioprotection by intraesophageal administration of MnSOD-PL was correlated with a reduced level of radiation-induced HR in esophageal cells. These results demonstrate the efficacy of MnSOD-PL for suppressing radiation-induced HR in vivo.

MnSOD deficiency results in elevated oxidative stress and decreased mitochondrial function but does not lead to muscle atrophy during aging.

PubMed

Lustgarten, Michael S; Jang, Youngmok C; Liu, Yuhong; Qi, Wenbo; Qin, Yuejuan; Dahia, Patricia L; Shi, Yun; Bhattacharya, Arunabh; Muller, Florian L; Shimizu, Takahiko; Shirasawa, Takuji; Richardson, Arlan; Van Remmen, Holly

2011-06-01

In a previous study, we reported that a deficiency in MnSOD activity (approximately 80% reduction) targeted to type IIB skeletal muscle fibers was sufficient to elevate oxidative stress and to reduce muscle function in young adult mice (TnIFastCreSod2(fl/fl) mice). In this study, we used TnIFastCreSod2(fl/fl) mice to examine the effect of elevated oxidative stress on mitochondrial function and to test the hypothesis that elevated oxidative stress and decreased mitochondrial function over the lifespan of the TnIFastCreSod2(fl/fl) mice would be sufficient to accelerate muscle atrophy associated with aging. We found that mitochondrial function is reduced in both young and old TnIFastCreSod2(fl/fl) mice, when compared with control mice. Complex II activity is reduced by 47% in young and by approximately 90% in old TnIFastCreSod2(fl/fl) mice, and was found to be associated with reduced levels of the catalytic subunits for complex II, SDHA and SDHB. Complex II-linked mitochondrial respiration is reduced by approximately 70% in young TnIFastCreSod2(fl/fl) mice. Complex II-linked mitochondrial Adenosine-Tri-Phosphate (ATP) production is reduced by 39% in young and was found to be almost completely absent in old TnIFastCreSod2(fl/fl) mice. Furthermore, in old TnIFastCreSod2(fl/fl) mice, aconitase activity is almost completely abolished; mitochondrial superoxide release remains > 2-fold elevated; and oxidative damage (measured as F(2) - isoprostanes) is increased by 30% relative to age-matched controls. These data show that despite elevated skeletal muscle-specific mitochondrial oxidative stress, oxidative damage, and complex II-linked mitochondrial dysfunction, age-related muscle atrophy was not accelerated in old TnIFastCreSod2(fl/fl) mice, suggesting mitochondrial oxidative stress may not be causal for age-related muscle atrophy. No claim to original US government works. Aging Cell © 2011 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

Dietary Manganese Modulates PCB126 Toxicity, Metal Status, and MnSOD in the Rat

PubMed Central

Wang, Bingxuan; Klaren, William D.; Wels, Brian R.; Simmons, Donald L.; Olivier, Alicia K.; Wang, Kai; Robertson, Larry W.; Ludewig, Gabriele

2016-01-01

PCB126 (3,3′,4,4′,5-pentachlorobiphenyl) is a potent aryl hydrocarbon receptor agonist and induces oxidative stress. Because liver manganese (Mn) levels decrease in response to PCB126, a Mn dietary study was designed to investigate the role of Mn in PCB126 toxicity. Male Sprague Dawley rats received diets containing 0, 10, or 150 ppm added Mn for 3 weeks, followed by a single ip injection of corn oil or PCB126 (5 µmol/kg body weight). After 2 weeks, Mn, Cu, Zn, and Fe levels in the heart, liver, and liver mitochondria, and Mn-containing superoxide dismutase (MnSOD) and metallothionein mRNA, MnSOD protein, and MnSOD activity were determined. Mn levels in liver, heart, and liver mitochondria were strongly decreased by the Mn-deficient diet. Small effects on Fe levels and a stepwise increase in MnSOD activity with dietary Mn were also visible. PCB126 caused profound changes in Cu (up), Zn, Fe, and Mn (down) in liver, but not in heart, and differing effects (Cu, Zn, and Fe up, Mn down) in liver mitochondria. Liver MnSOD and metallothionein mRNA levels and MnSOD protein were increased but MnSOD activity was decreased by PCB126. PCB126-induced liver enlargement was dose-dependently reduced with increasing dietary Mn. These changes in metals homeostasis and MnSOD activity in liver but not heart may be a/the mechanism of PCB126 liver-specific toxicity. Specifically, transport of Fenton metals (Cu, Fe) into and Mn out of the mitochondria, a probable mechanism for lower MnSOD activity, may be a/the cause of PCB126-induced oxidative stress. The role of metallothioneins needs further evaluation. Dietary Mn slightly alleviated PCB126-induced toxicities. PMID:26660635

Mining the enzymes involved in the detoxification of reactive oxygen species (ROS) in sugarcane.

PubMed

Kurama, Eiko E; Fenille, Roseli C; Rosa, Vicente E; Rosa, Daniel D; Ulian, Eugenio C

2002-07-01

Summary Adopting the sequencing of expressed sequence tags (ESTs) of a sugarcane database derived from libraries induced and not induced by pathogens, we identified EST clusters homologous to genes corresponding to enzymes involved in the detoxification of reactive oxygen species. The predicted amino acids of these enzymes are superoxide dismutases (SODs), glutathione-S-transferase (GST), glutathione peroxidase (GPX), and catalases. Three MnSOD mitochondrial precursors and 10 CuZnSOD were identified in sugarcane: the MnSOD mitochondrial precursor is 96% similar to the maize MnSOD mitochondrial precursor and, of the 10 CuZnSOD identified, seven were 98% identical to maize cytosolic CuZnSOD4 and one was 67% identical to putative peroxisomal CuZnSOD from Arabidopsis. Three homologues to class Phi GST were 87-88% identical to GST III from maize. Five GPX homologues were identified: three were homologous to cytosolic GPX from barley, one was 88% identical to phospholipid hydroperoxide glutathione peroxidase (PHGPX) from rice, and the last was 71% identical to GPX from A. thaliana. Three enzymes similar to maize catalase were identified in sugarcane: two were similar to catalase isozyme 3 and catalase chain 3 from maize, which are mitochondrial, and one was similar to catalase isozyme 1 from maize, whose location is peroxisomal subcellular. All enzymes were induced in all sugarcane libraries (flower, seed, root, callus, leaves) and also in the pathogen-induced libraries, except for CuZnSOD whose cDNA was detected in none of the libraries induced by pathogens (Acetobacter diazotroficans and Herbaspirillum rubrisubalbicans). The expression of the enzymes SOD, GST, GPX, and catalases involved in the detoxification was examined using reverse transcriptase-polymerase chain reaction in cDNA from leaves of sugarcane under biotic stress conditions, inoculated with Puccinia melanocephala, the causal agent of sugarcane rust disease.

Sequestosome 1/p62 links familial ALS mutant SOD1 to LC3 via an ubiquitin-independent mechanism.

PubMed

Gal, Jozsef; Ström, Anna-Lena; Kwinter, David M; Kilty, Renée; Zhang, Jiayu; Shi, Ping; Fu, Weisi; Wooten, Marie W; Zhu, Haining

2009-11-01

The p62/sequestosome 1 protein has been identified as a component of pathological protein inclusions in neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). P62 has also been implicated in autophagy, a process of mass degradation of intracellular proteins and organelles. Autophagy is a critical pathway for degrading misfolded and/or damaged proteins, including the copper-zinc superoxide dismutase (SOD1) mutants linked to familial ALS. We previously reported that p62 interacted with ALS mutants of SOD1 and that the ubiquitin-association domain of p62 was dispensable for the interaction. In this study, we identified two distinct regions of p62 that were essential to its binding to mutant SOD1: the N-terminal Phox and Bem1 (PB1) domain (residues 1-104) and a separate internal region (residues 178-224) termed here as SOD1 mutant interaction region (SMIR). The PB1 domain is required for appropriate oligomeric status of p62 and the SMIR is the actual region interacting with mutant SOD1. Within the SMIR, the conserved W184, H190 and positively charged R183, R186, K187, and K189 residues are critical to the p62-mutant SOD1 interaction as substitution of these residues with alanine resulted in significantly abolished binding. In addition, SMIR and the p62 sequence responsible for the interaction with LC3, a protein essential for autophagy activation, are independent of each other. In cells lacking p62, the existence of mutant SOD1 in acidic autolysosomes decreased, suggesting that p62 can function as an adaptor between mutant SOD1 and the autophagy machinery. This study provides a novel molecular mechanism by which mutant SOD1 can be recognized by p62 in an ubiquitin-independent fashion and targeted for the autophagy-lysosome degradation pathway.

Synergistic Effects of GhSOD1 and GhCAT1 Overexpression in Cotton Chloroplasts on Enhancing Tolerance to Methyl Viologen and Salt Stresses

PubMed Central

Luo, Xiaoli; Wu, Jiahe; Li, Yuanbao; Nan, Zhirun; Guo, Xing; Wang, Yixue; Zhang, Anhong; Wang, Zhian; Xia, Guixian; Tian, Yingchuan

2013-01-01

In plants, CuZn superoxide dismutase (CuZnSOD, EC l.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11), and catalase (CAT, EC l.11.1.6) are important scavengers of reactive oxygen species (ROS) to protect the cell from damage. In the present study, we isolated three homologous genes (GhSOD1, GhAPX1, and GhCAT1) from Gossypium hirsutum. Overexpressing cassettes containing chimeric GhSOD1, GhAPX1, or GhCAT1 were introduced into cotton plants by Agrobacterium transformation, and overexpressed products of these genes were transported into the chloroplasts by transit peptide, as expected. The five types of transgenic cotton plants that overexpressed GhSOD1, GhAPX1, GhCAT1, GhSOD1 and GhAPX1 stack (SAT), and GhSOD1 and GhCAT1 stack (SCT) were developed. Analyses in the greenhouse showed that the transgenic plants had higher tolerance to methyl viologen (MV) and salinity than WT plants. Interestingly, SCT plants suffered no damage under stress conditions. Based on analyses of enzyme activities, electrolyte leakage, chlorophyll content, photochemical yield (Fv/Fm), and biomass accumulation under stresses, the SCT plants that simultaneously overexpressed GhSOD1 and GhCAT1 appeared to benefit from synergistic effects of two genes and exhibited the highest tolerance to MV and salt stress among the transgenic lines, while the SAT plants simultaneously overexpressing GhSOD1 and GhAPX1 did not. In addition, transgenic plants overexpressing antioxidant enzymes in their chloroplasts had higher tolerance to salt stress than those expressing the genes in their cytoplasms, although overall enzyme activities were almost the same. Therefore, the synergistic effects of GhSOD1 and GhCAT1 in chloroplasts provide a new strategy for enhancing stress tolerance to avoid yield loss. PMID:23335985

Human SOD1 ALS Mutations in a Drosophila Knock-In Model Cause Severe Phenotypes and Reveal Dosage-Sensitive Gain- and Loss-of-Function Components.

PubMed

Şahin, Aslı; Held, Aaron; Bredvik, Kirsten; Major, Paxton; Achilli, Toni-Marie; Kerson, Abigail G; Wharton, Kristi; Stilwell, Geoff; Reenan, Robert

2017-02-01

Amyotrophic Lateral Sclerosis (ALS) is the most common adult-onset motor neuron disease and familial forms can be caused by numerous dominant mutations of the copper-zinc superoxide dismutase 1 (SOD1) gene. Substantial efforts have been invested in studying SOD1-ALS transgenic animal models; yet, the molecular mechanisms by which ALS-mutant SOD1 protein acquires toxicity are not well understood. ALS-like phenotypes in animal models are highly dependent on transgene dosage. Thus, issues of whether the ALS-like phenotypes of these models stem from overexpression of mutant alleles or from aspects of the SOD1 mutation itself are not easily deconvolved. To address concerns about levels of mutant SOD1 in disease pathogenesis, we have genetically engineered four human ALS-causing SOD1 point mutations (G37R, H48R, H71Y, and G85R) into the endogenous locus of Drosophila SOD1 (dsod) via ends-out homologous recombination and analyzed the resulting molecular, biochemical, and behavioral phenotypes. Contrary to previous transgenic models, we have recapitulated ALS-like phenotypes without overexpression of the mutant protein. Drosophila carrying homozygous mutations rendering SOD1 protein enzymatically inactive (G85R, H48R, and H71Y) exhibited neurodegeneration, locomotor deficits, and shortened life span. The mutation retaining enzymatic activity (G37R) was phenotypically indistinguishable from controls. While the observed mutant dsod phenotypes were recessive, a gain-of-function component was uncovered through dosage studies and comparisons with age-matched dsod null animals, which failed to show severe locomotor defects or nerve degeneration. We conclude that the Drosophila knock-in model captures important aspects of human SOD1-based ALS and provides a powerful and useful tool for further genetic studies. Copyright © 2017 by the Genetics Society of America.

Superoxide dismutase (SOD) in boar spermatozoa: purification, biochemical properties and changes in activity during semen storage (16°C) in different extenders.

PubMed

Orzołek, Aleksandra; Wysocki, Paweł; Strzeżek, Jerzy; Kordan, Władysław

2013-03-01

The antioxidant system in semen is composed of enzymes, low-molecular weight antioxidants and seminal plasma proteins. Loss of enzymatic activity of superoxide dismutase (SOD) during semen preservation may cause insufficient antioxidant defense of boar spermatozoa. The aim of this study was to isolate and characterize SOD molecular forms from spermatozoa and to describe changes in SOD activity in boar sperm during preservation at 16°C. Sperm extracts were prepared from fresh or diluted semen and used for SOD purification or activity measurement. Ion-exchange chromatography and gel filtration was used to purify SOD molecular forms. BTS, Dilu Cell, M III and Vitasem were used as diluents for 5-day storage of semen at +16°C. The molecular form of SOD released from spermatozoa after cold shock and homogenization had a molecular weight of approximately 67kDa. The activity of the SOD form was the highest at pH 10 within the temperature range between 20 and 45°C. The enzymatic activity of form released after cold shock was inhibited by H2O2 and diethyldithiocarbamate (DDC; by 65 and 40%, respectively). The SOD form released by homogenization was inhibited by H2O2 and DDC (40%). The molecular form released after urea treatment was a 30kDa protein with maximum activity at 20°C and pH 10. Enzymatic activity of this form was inhibited by H2O2 by 35%, DDC by 80% and 2-mercaptoethanol by 15%. The antigenic determinants of SOD isolated from boar seminal plasma and spermatozoa were similar to each other. Susceptibility of spermatozoa to cold shock increased during storage, but the differences between extenders were statistically non-significant. Copyright © 2013 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Oxidative Stress Induced Age Dependent Meibomian Gland Dysfunction in Cu, Zn-Superoxide Dismutase-1 (Sod1) Knockout Mice

PubMed Central

Ibrahim, Osama M. A.; Dogru, Murat; Matsumoto, Yukihiro; Igarashi, Ayako; Kojima, Takashi; Wakamatsu, Tais Hitomi; Inaba, Takaaki; Shimizu, Takahiko; Shimazaki, Jun; Tsubota, Kazuo

2014-01-01

Purpose The purpose of our study was to investigate alterations in the meibomian gland (MG) in Cu, Zn-Superoxide Dismutase-1 knockout (Sod1 −/−) mouse. Methods Tear function tests [Break up time (BUT) and cotton thread] and ocular vital staining test were performed on Sod1 −/− male mice (n = 24) aged 10 and 50 weeks, and age and sex matched wild–type (+/+) mice (n = 25). Tear and serum samples were collected at sacrifice for inflammatory cytokine assays. MG specimens underwent Hematoxylin and Eosin staining, Mallory staining for fibrosis, Oil Red O lipid staining, TUNEL staining, immunohistochemistry stainings for 4HNE, 8-OHdG and CD45. Transmission electron microscopic examination (TEM) was also performed. Results Corneal vital staining scores in the Sod1 −/− mice were significantly higher compared with the wild type mice throughout the follow-up. Tear and serum IL-6 and TNF-α levels also showed significant elevations in the 10 to 50 week Sod1 −/− mice. Oil Red O staining showed an accumulation of large lipid droplets in the Sod1 −/− mice at 50 weeks. Immunohistochemistry revealed both increased TUNEL and oxidative stress marker stainings of the MG acinar epithelium in the Sod1 −/− mice compared to the wild type mice. Immunohistochemistry staining for CD45 showed increasing inflammatory cell infiltrates from 10 to 50 weeks in the Sod1 −/− mice compared to the wild type mice. TEM revealed prominent mitochondrial changes in 50 week Sod1 −/− mice. Conclusions Our results suggest that reactive oxygen species might play a vital role in the pathogensis of meibomian gland dysfunction. The Sod1 −/− mouse appears to be a promising model for the study of reactive oxygen species associated MG alterations. PMID:25036096

Genetic Polymorphisms in SOD (rs2070424, rs7880) and CAT (rs7943316, rs1001179) Enzymes Are Associated with Increased Body Fat Percentage and Visceral Fat in an Obese Population from Central Mexico.

PubMed

Hernández-Guerrero, César; Hernández-Chávez, Paulina; Romo-Palafox, Inés; Blanco-Melo, Grecia; Parra-Carriedo, Alicia; Pérez-Lizaur, Ana

2016-07-01

Oxidative disturbance is an important factor involved in the etiology of comorbidities associated with obesity. Genetic polymorphisms such as SOD1 -251A>G, SOD2 47 C>T, CAT -21A>T and CAT -262 C>T have been described to alter the activity of antioxidant enzymes. The aim of the present work was to analyze the association of the mentioned SNPs with obesity and their relationship with anthropometric and clinical variables in this group. The study included 416 Mexican women (208 normal weight, NW and 208 subjects with obesity, OB). Dietary intake, anthropometric, biochemical and clinical features were evaluated and then analyzed in function of the genotypes. The mutated carriers (GA+GG) of SOD -251 were significantly higher in the OB group (0.24) compared to the NW group (0.08). The other SNPs showed no differences compared with control group. When comparing carrier mutated subjects with obesity vs. wild-type obese participants with the SNPs SOD1 -251, SOD2 47 and CAT -262, the carriers showed a significantly (p <0.05) higher value in body fat percentage. Also, carriers of SOD2 47 and CAT-262 showed significantly higher values (p = 0.002) and (p = 0.01), respectively, when visceral fat was compared between groups. Systolic blood pressure was significantly higher (p = 0.02) in carriers of mutated CAT-21. SOD1 -251A>G is associated with obesity independent of the presence of diabetes or dyslipidemia. Mutated obese carries of SOD1 -251, SOD2 47 and CAT -262 are associated with a higher distribution of fat in comparison with obese wild-type carriers. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

Immunization with a DNA vaccine encoding Toxoplasma gondii Superoxide dismutase (TgSOD) induces partial immune protection against acute toxoplasmosis in BALB/c mice.

PubMed

Liu, Yuan; Cao, Aiping; Li, Yawen; Li, Xun; Cong, Hua; He, Shenyi; Zhou, Huaiyu

2017-06-07

Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects all warm-blooded animals including humans and causes toxoplasmosis. An effective vaccine could be an ideal choice for preventing and controlling toxoplasmosis. T. gondii Superoxide dismutase (TgSOD) might participate in affecting the intracellular growth of both bradyzoite and tachyzoite forms. In the present study, the TgSOD gene was used to construct a DNA vaccine (pEGFP-SOD). TgSOD gene was amplified and inserted into eukaryotic vector pEGFP-C1 and formed the DNA vaccine pEGFP-SOD. Then the BALB/c mice were immunized intramuscularly with the DNA vaccine and those injected with pEGFP-C1, PBS or nothing were treated as controls. Four weeks after the last immunization, all mouse groups followed by challenging intraperitoneally with tachyzoites of T. gondii ME49 strain. Results showed higher levels of total IgG, IgG2α in the sera and interferon gamma (IFN-γ) in the splenocytes from pEGFP-SOD inoculated mice than those unvaccinated, or inoculated with either empty plasmid vector or PBS. The proportions of CD4 + T cells and CD8 + T cells in the spleen from pEGFP-SOD inoculated mice were significantly (p < 0.05) increased compared to control groups. In addition, the survival time of mice immunized with pEGFP-SOD was significantly prolonged as compared to the controls (p < 0.05) although all the mice died. The present study revealed that the DNA vaccine triggered strong humoral and cellular immune responses, and aroused partial protective immunity against acute T. gondii infection in BALB/c mice. The collective data suggests the SOD may be a potential vaccine candidate for further development.

Combined proteomic and molecular approaches for cloning and characterization of copper-zinc superoxide dismutase (Cu, Zn-SOD2) from garlic (Allium sativum).

PubMed

Hadji Sfaxi, Imen; Ezzine, Aymen; Coquet, Laurent; Cosette, Pascal; Jouenne, Thierry; Marzouki, M Nejib

2012-09-01

Superoxide dismutases (SODs; EC 1.15.1.1) are key enzymes in the cells protection against oxidant agents. Thus, SODs play a major role in the protection of aerobic organisms against oxygen-mediated damages. Three SOD isoforms were previously identified by zymogram staining from Allium sativum bulbs. The purified Cu, Zn-SOD2 shows an antagonist effect to an anticancer drug and alleviate cytotoxicity inside tumor cells lines B16F0 (mouse melanoma cells) and PAE (porcine aortic endothelial cells). To extend the characterization of Allium SODs and their corresponding genes, a proteomic approach was applied involving two-dimensional gel electrophoresis and LC-MS/MS analyses. From peptide sequence data obtained by mass spectrometry and sequences homologies, primers were defined and a cDNA fragment of 456 bp was amplified by RT-PCR. The cDNA nucleotide sequence analysis revealed an open reading frame coding for 152 residues. The deduced amino acid sequence showed high identity (82-87%) with sequences of Cu, Zn-SODs from other plant species. Molecular analysis was achieved by a protein 3D structural model.

Characterization, molecular modelling and developmental expression of zebrafish manganese superoxide dismutase.

PubMed

Lin, Chi-Tsai; Tseng, Wen-Chung; Hsiao, Nai-Wan; Chang, Hsiao-Huang; Ken, Chuian-Fu

2009-08-01

A 977 bp cDNA containing an open reading frame encoding 224 amino acid residues of manganese superoxide dismutase was cloned from zebrafish (zMn-SOD). The deduced amino acid sequence showed high identity with the sequences of Mn-SODs from human (85.1%) to nematode (61.6%). The 3-D structure model was superimposed on the relative domains of human Mn-SOD with the root mean square (rms) deviation of 0.0919 A. The recombinant mature zMn-SOD with enzyme activity was purified using His-tag technique. The half-life of the enzyme is approximately 48 min and its thermal inactivation rate constant k(d) is 0.0154 min(-1)at 70 degrees C. The enzyme was active under a broad pH (2.2-11.2) and in the presence of up to 4% SDS. Real-time RT-PCR assay was used to detect the zMn-SOD mRNA expression during the developmental stages following a challenge with paraquat. A high level expression of Mn-SOD mRNA was detected at the cleavage stage, but decreased significantly under paraquat treatment. The results indicated that Mn-SOD plays an important role during embryonic development.

Mutant Copper-Zinc Superoxide Dismutase (SOD1) Induces Protein Secretion Pathway Alterations and Exosome Release in Astrocytes

PubMed Central

Basso, Manuela; Pozzi, Silvia; Tortarolo, Massimo; Fiordaliso, Fabio; Bisighini, Cinzia; Pasetto, Laura; Spaltro, Gabriella; Lidonnici, Dario; Gensano, Francesco; Battaglia, Elisa; Bendotti, Caterina; Bonetto, Valentina

2013-01-01

Amyotrophic lateral sclerosis is the most common motor neuron disease and is still incurable. The mechanisms leading to the selective motor neuron vulnerability are still not known. The interplay between motor neurons and astrocytes is crucial in the outcome of the disease. We show that mutant copper-zinc superoxide dismutase (SOD1) overexpression in primary astrocyte cultures is associated with decreased levels of proteins involved in secretory pathways. This is linked to a general reduction of total secreted proteins, except for specific enrichment in a number of proteins in the media, such as mutant SOD1 and valosin-containing protein (VCP)/p97. Because there was also an increase in exosome release, we can deduce that astrocytes expressing mutant SOD1 activate unconventional secretory pathways, possibly as a protective mechanism. This may help limit the formation of intracellular aggregates and overcome mutant SOD1 toxicity. We also found that astrocyte-derived exosomes efficiently transfer mutant SOD1 to spinal neurons and induce selective motor neuron death. We conclude that the expression of mutant SOD1 has a substantial impact on astrocyte protein secretion pathways, contributing to motor neuron pathology and disease spread. PMID:23592792

Weakness of whole muscles in mice deficient in Cu, Zn superoxide dismutase is not explained by defects at the level of the contractile apparatus.

PubMed

Larkin, Lisa M; Hanes, Michael C; Kayupov, Erdan; Claflin, Dennis R; Faulkner, John A; Brooks, Susan V

2013-08-01

Mice deficient in Cu,Zn superoxide dismutase (Sod1 (-/-) mice) demonstrate elevated oxidative stress associated with rapid age-related declines in muscle mass and force. The decline in mass for muscles of Sod1 (-/-) mice is explained by a loss of muscle fibers, but the mechanism underlying the weakness is not clear. We hypothesized that the reduced maximum isometric force (F o) normalized by cross-sectional area (specific F o) for whole muscles of Sod1 (-/-) compared with wild-type (WT) mice is due to decreased specific F o of individual fibers. Force generation was measured for permeabilized fibers from muscles of Sod1 (-/-) and WT mice at 8 and 20 months of age. WT mice were also studied at 28 months to determine whether any deficits observed for fibers from Sod1 (-/-) mice were similar to those observed in old WT mice. No effects of genotype were observed for F o or specific F o at either 8 or 20 months, and no age-associated decrease in specific F o was observed for fibers from Sod1 (-/-) mice, whereas specific F o for fibers of WT mice decreased by 20 % by 28 months. Oxidative stress has also been associated with decreased maximum velocity of shortening (V max), and we found a 10 % lower V max for fibers from Sod1 (-/-) compared with WT mice at 20 months. We conclude that the low specific F o of muscles of Sod1 (-/-) mice is not explained by damage to contractile proteins. Moreover, the properties of fibers of Sod1 (-/-) mice do not recapitulate those observed with aging in WT animals.

Plasma superoxide dismutase-1 as a surrogate marker of vivax malaria severity.

PubMed

Andrade, Bruno B; Reis-Filho, Antonio; Souza-Neto, Sebastião Martins; Raffaele-Netto, Imbroinise; Camargo, Luis M A; Barral, Aldina; Barral-Netto, Manoel

2010-04-06

Severe outcomes have been described for both Plasmodium falciparum and P. vivax infections. The identification of sensitive and reliable markers of disease severity is fundamental to improving patient care. An intense pro-inflammatory response with oxidative stress and production of reactive oxygen species is present in malaria. Inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and antioxidant agents such as superoxide dismutase-1 (SOD-1) are likely candidate biomarkers for disease severity. Here we tested whether plasma levels of SOD-1 could serve as a biomarker of severe vivax malaria. Plasma samples were obtained from residents of the Brazilian Amazon with a high risk for P. vivax transmission. Malaria diagnosis was made by both microscopy and nested PCR. A total of 219 individuals were enrolled: non-infected volunteers (n = 90) and individuals with vivax malaria: asymptomatic (n = 60), mild (n = 50) and severe infection (n = 19). SOD-1 was directly associated with parasitaemia, plasma creatinine and alanine amino-transaminase levels, while TNF-alpha correlated only with the later enzyme. The predictive power of SOD-1 and TNF-alpha levels was compared. SOD-1 protein levels were more effective at predicting vivax malaria severity than TNF-alpha. For discrimination of mild infection, elevated SOD-1 levels showed greater sensitivity than TNF-alpha (76% vs. 30% respectively; p<0.0001), with higher specificity (100% vs. 97%; p<0.0001). In predicting severe vivax malaria, SOD-1 levels exhibited higher sensitivity than TNF-alpha (80% vs. 56%, respectively; p<0.0001; likelihood ratio: 7.45 vs. 3.14; p<0.0001). Neither SOD-1 nor TNF-alpha could discriminate P. vivax infections from those caused by P. falciparum. SOD-1 is a powerful predictor of disease severity in individuals with different clinical presentations of vivax malaria.

Effect of CCS on the accumulation of FALS SOD1 mutant-containing aggregates and on mitochondrial translocation of SOD1 mutants: implication of a free radical hypothesis.

PubMed

Kim, Ha Kun; Chung, Youn Wook; Chock, P Boon; Yim, Moon B

2011-05-15

Missense mutations of SOD1 are linked to familial amyotrophic lateral sclerosis (FALS) through a yet-to-be identified toxic-gain-of-function. One of the proposed mechanisms involves enhanced aggregate formation. However, a recent study showed that dual transgenic mice overexpressing both G93A and CCS copper chaperone (G93A/CCS) exhibit no SOD1-positive aggregates yet show accelerated FALS symptoms with enhanced mitochondrial pathology compared to G93A mice. Using a dicistronic mRNA to simultaneously generate hSOD1 mutants, G93A, A4V and G85R, and hCCS in AAV293 cells, we revealed: (i) CCS is degraded primarily via a macroautophagy pathway. It forms a stable heterodimer with inactive G85R, and via its novel copper chaperone-independent molecular chaperone activity facilitates G85R degradation via a macroautophagy-mediated pathway. For active G93A and A4V, CCS catalyzes their maturation to form active and soluble homodimers. (ii) CCS reduces, under non-oxidative conditions, yet facilitates in the presence of H(2)O(2), mitochondrial translocation of inactive SOD1 mutants. These results, together with previous reports showing FALS SOD1 mutants enhanced free radical-generating activity, provide a mechanistic explanation for the observations with G93A/CCS dual transgenic mice and suggest that free radical generation by FALS SOD1, enhanced by CCS, may, in part, be responsible for the FALS SOD1 mutant-linked aggregation, mitochondrial translocation, and degradation. Published by Elsevier Inc.

Copper/zinc superoxide dismutase insufficiency impairs progesterone secretion and fertility in female mice.

PubMed

Noda, Yoshihiro; Ota, Kuniaki; Shirasawa, Takuji; Shimizu, Takahiko

2012-01-01

Copper/zinc superoxide dismutase (CuZn-SOD, SOD1) is one of the major antioxidant enzymes, and is localized in the cytoplasm to scavenge superoxide. To investigate the physiological role of SOD1 in the ovaries, we analyzed the fertility of Sod1-deficient female mice. To evaluate their hormonal metabolism, we measured pituitary and ovarian hormone levels in the plasma of the mutant mice. Plasma follicle-stimulating hormone, luteinizing hormone, and estradiol were not altered in the mutant compared to the wild-type females, while the plasma progesterone level was significantly reduced in the mutant females. Furthermore, the mutant mice showed decreased progesterone secretion under the condition of superovulation. In a histochemical analysis, we observed a remarkable reduction in the corpus luteum area in the mutant ovaries without atrophic changes. The mutant mice also displayed enhanced superoxide generation in the region surrounding the corpora lutea, which was associated with increased apoptotic cells and suppressed vasculature. These results suggested that SOD1 deficiency dysregulated luteal formation because of increased superoxide generation in the ovary. In vitro fertilization experiments showed no abnormal fertilization of Sod1-deficient oocytes. In addition, when Sod1-deficient embryos were transferred into the oviducts of wild-type females, mutant embryos developed at a normal rate, indicating that SOD1 deficiency in embryos did not cause miscarriage in the uterus of wild-type females. These results indicated that increased intracellular ROS impaired luteal formation and progesterone production in the mutant females, thus suggesting that SOD1 plays a crucial role in both the luteal function and the maintenance of fertility in female mice.

Mitochondrial antioxidative capacity regulates muscle glucose uptake in the conscious mouse: effect of exercise and diet.

PubMed

Kang, Li; Lustig, Mary E; Bonner, Jeffrey S; Lee-Young, Robert S; Mayes, Wesley H; James, Freyja D; Lin, Chien-Te; Perry, Christopher G R; Anderson, Ethan J; Neufer, P Darrell; Wasserman, David H

2012-10-15

The objective of this study was to test the hypothesis that exercise-stimulated muscle glucose uptake (MGU) is augmented by increasing mitochondrial reactive oxygen species (mtROS) scavenging capacity. This hypothesis was tested in genetically altered mice fed chow or a high-fat (HF) diet that accelerates mtROS formation. Mice overexpressing SOD2 (sod2(Tg)), mitochondria-targeted catalase (mcat(Tg)), and combined SOD2 and mCAT (mtAO) were used to increase mtROS scavenging. mtROS was assessed by the H(2)O(2) emitting potential (JH(2)O(2)) in muscle fibers. sod2(Tg) did not decrease JH(2)O(2) in chow-fed mice, but decreased JH(2)O(2) in HF-fed mice. mcat(Tg) and mtAO decreased JH(2)O(2) in both chow- and HF-fed mice. In parallel, the ratio of reduced to oxidized glutathione (GSH/GSSG) was unaltered in sod2(Tg) in chow-fed mice, but was increased in HF-fed sod2(Tg) and both chow- and HF-fed mcat(Tg) and mtAO. Nitrotyrosine, a marker of NO-dependent, reactive nitrogen species (RNS)-induced nitrative stress, was decreased in both chow- and HF-fed sod2(Tg), mcat(Tg), and mtAO mice. This effect was not changed with exercise. Kg, an index of MGU was assessed using 2-[(14)C]-deoxyglucose during exercise. In chow-fed mice, sod2(Tg), mcat(Tg), and mtAO increased exercise Kg compared with wild types. Exercise Kg was also augmented in HF-fed sod2(Tg) and mcat(Tg) mice but unchanged in HF-fed mtAO mice. In conclusion, mtROS scavenging is a key regulator of exercise-mediated MGU and this regulation depends on nutritional state.

Mitochondrial dynamics and bioenergetic dysfunction is associated with synaptic alterations in mutant SOD1 motor neurons

PubMed Central

Magrané, Jordi; Sahawneh, Mary Anne; Przedborski, Serge; Estévez, Álvaro G.; Manfredi, Giovanni

2012-01-01

Mutations in Cu,Zn superoxide dismutase (SOD1) cause familial amyotrophic lateral sclerosis (FALS), a rapidly fatal motor neuron disease. Mutant SOD1 has pleiotropic toxic effects on motor neurons, among which mitochondrial dysfunction has been proposed as one of the contributing factors in motor neuron demise. Mitochondria are highly dynamic in neurons; they are constantly reshaped by fusion and move along neurites to localize at sites of high-energy utilization, such as synapses. The finding of abnormal mitochondria accumulation in neuromuscular junctions, where the SOD1-FALS degenerative process is though to initiate, suggests that impaired mitochondrial dynamics in motor neurons may be involved in pathogenesis. We addressed this hypothesis by live imaging microscopy of photo-switchable fluorescent mitoDendra in transgenic rat motor neurons expressing mutant or wild type human SOD1. We demonstrate that mutant SOD1 motor neurons have impaired mitochondrial fusion in axons and cell bodies. Mitochondria also display selective impairment of retrograde axonal transport, with reduced frequency and velocity of movements. Fusion and transport defects are associated with smaller mitochondrial size, decreased mitochondrial density, and defective mitochondrial membrane potential. Furthermore, mislocalization of mitochondria at synapses among motor neurons, in vitro, correlates with abnormal synaptic number, structure, and function. Dynamics abnormalities are specific to mutant SOD1 motor neuron mitochondria, since they are absent in wild type SOD1 motor neurons, they do not involve other organelles, and they are not found in cortical neurons. Taken together, these results suggest that impaired mitochondrial dynamics may contribute to the selective degeneration of motor neurons in SOD1-FALS. PMID:22219285

Superoxide dismutase recombinant Lactobacillus fermentum ameliorates intestinal oxidative stress through inhibiting NF-κB activation in a trinitrobenzene sulphonic acid-induced colitis mouse model.

PubMed

Hou, C L; Zhang, J; Liu, X T; Liu, H; Zeng, X F; Qiao, S Y

2014-06-01

Superoxide dismutase (SOD) can prevent and cure inflammatory bowel diseases by decreasing the amount of reactive oxygen species. Unfortunately, short half-life of SOD in the gastrointestinal tract limited its application in the intestinal tract. This study aimed to investigate the treatment effects of recombinant SOD Lactobacillus fermentum in a colitis mouse model. In this study, we expressed the sodA gene in Lact. fermentum I5007 to obtain the SOD recombinant strain. Then, we determined the therapeutic effects of this SOD recombinant strain in a trinitrobenzene sulphonic acid (TNBS)-induced colitis mouse model. We found that SOD activity in the recombinant Lact. fermentum was increased by almost eightfold compared with that in the wild type. Additionally, both the wild type and the recombinant Lact. fermentum increased the numbers of lactobacilli in the colon of mice (P < 0·05). Colitis mice treated with recombinant Lact. fermentum showed a higher survival rate and lower disease activity index (P < 0·05). Recombinant Lact. fermentum significantly decreased colonic mucosa histological scoring for infiltration of inflammatory cells, lipid peroxidation, the expression of pro-inflammatory cytokines and myeloperoxidase (P < 0·05) and inhibited NF-κB activity in colitis mice (P < 0·05). SOD recombinant Lact. fermentum significantly reduced oxidative stress and inflammation through inhibiting NF-κB activation in the TNBS-induced colitis model. This study provides insights into the anti-inflammatory effects of SOD recombinant Lact. fermentum, indicating the potential therapeutic effects in preventing and curing intestinal bowel diseases. © 2014 The Society for Applied Microbiology.

Unraveling ALS due to SOD1 mutation through the combination of brain and cervical cord MRI.

PubMed

Agosta, Federica; Spinelli, Edoardo Gioele; Marjanovic, Ivan V; Stevic, Zorica; Pagani, Elisabetta; Valsasina, Paola; Salak-Djokic, Biljana; Jankovic, Milena; Lavrnic, Dragana; Kostic, Vladimir S; Filippi, Massimo

2018-02-20

To explore structural and functional changes of the brain and cervical cord in patients with amyotrophic lateral sclerosis (ALS) due to mutation in the superoxide dismutase ( SOD1 ) gene compared with sporadic ALS. Twenty patients with SOD1 ALS, 11 with sporadic ALS, and 33 healthy controls underwent clinical evaluation and brain MRI. Cortical thickness analysis, diffusion tensor MRI of the corticospinal tracts (CST) and corpus callosum, and resting-state functional connectivity were performed. Patients with ALS also underwent cervical cord MRI to evaluate cord cross-sectional area and magnetization transfer ratio (MTR). Patients with SOD1 ALS showed longer disease duration and slower rate of functional decline relative to those with sporadic ALS. No cortical thickness abnormalities were found in patients with ALS compared with controls. Fractional anisotropy showed that sporadic ALS patients had significant CST damage relative to both healthy controls ( p = 0.001-0.02) and SOD1-related ALS ( p = 0.05), although the latter showed alterations that were intermediate between controls and sporadic ALS. Functional hyperconnectivity of the motor cortex in the sensorimotor network was observed in patients with sporadic ALS relative to controls. Conversely, patients with SOD1 ALS showed lower cord cross-sectional area along the whole cervical cord relative to those with sporadic ALS ( p < 0.001). No cord MTR differences were found between patient groups. Patients with SOD1 ALS showed cervical cord atrophy relative to those with sporadic ALS and a relative preservation of brain motor structural and functional networks. Neurodegeneration in SOD1 ALS is likely to occur primarily in the spinal cord. An objective and accurate estimate of spinal cord damage has potential in the future assessment of preventive SOD1 ALS therapies. © 2018 American Academy of Neurology.

Axotomy-induced target disconnection promotes an additional death mechanism involved in motoneuron degeneration in ALS transgenic mice

PubMed Central

Haulcomb, Melissa M.; Mesnard, Nichole A.; Batka, Richard J.; Alexander, Thomas D.; Sanders, Virginia M.; Jones, Kathryn J.

2014-01-01

The target disconnection theory of amyotrophic lateral sclerosis (ALS) pathogenesis suggests disease onset is initiated by a peripheral pathological event resulting in neuromuscular junction loss and motoneuron (MN) degeneration. Pre-symptomatic mSOD1G93A mouse facial MN (FMN) are more susceptible to axotomy-induced cell death than wild-type (WT) FMN, which suggests additional CNS pathology. We have previously determined that the mSOD1 molecular response to facial nerve axotomy is phenotypically regenerative and indistinguishable from WT, whereas the surrounding microenvironment shows significant dysregulation in the mSOD1 facial nucleus. To elucidate the mechanisms underlying the enhanced mSOD1 FMN loss after axotomy, we superimposed the facial nerve axotomy model on pre-symptomatic mSOD1 mice and investigated gene expression for death receptor pathways after target disconnection by axotomy vs. disease progression. We determined that the TNFR1 death receptor pathway is involved in axotomy-induced FMN death in WT, and partially responsible for the mSOD1 FMN death. In contrast, an inherent mSOD1 CNS pathology resulted in a suppressed glial reaction and an upregulation in the Fas death pathway after target disconnection. We propose that the dysregulated mSOD1 glia fail to provide support to injured MN, leading to Fas-induced FMN death. Finally, we demonstrated that during disease progression, the mSOD1 facial nucleus displays target disconnection-induced gene expression changes that mirror those induced by axotomy. This validates the use of axotomy as an investigative tool in understanding the role of peripheral target disconnection in the pathogenesis of ALS. PMID:24424947

Role of copper transport protein Antioxidant-1 in Angiotensin II-induced hypertension: A key regulator of Extracellular SOD

PubMed Central

Ozumi, Kiyoshi; Sudhahar, Varadarajan; Kim, Ha Won; Chen, Gin-Fu; Kohno, Takashi; Finney, Lydia; Vogt, Stefan; McKinney, Ronald D.; Ushio-Fukai, Masuko; Fukai, Tohru

2012-01-01

Extracellular superoxide dismutase (SOD3) is a secretory copper enzyme involved in protecting angiotensin II (Ang II)-induced hypertension. We previously found that Ang II upregulates SOD3 expression and activity as a counter-regulatory mechanism; however, underlying mechanisms are unclear. Antioxidant-1 (Atox1) is shown to act as a copper-dependent transcription factor as well as copper chaperone for SOD3 in vitro, but its role in Ang II-induced hypertension in vivo is unknown. Here we show that Ang II infusion increases Atox1 expression as well as SOD3 expression and activity in aortas of wild-type mice, which are inhibited in mice lacking Atox1. Accordingly, Ang II increases vascular O2•− production, reduces endothelium-dependent vasodilation and increases vasoconstriction in mesenteric arterioles to a greater extent in Atox1−/− than in wild-type mice. This contributes to augmented hypertensive response to Ang II in Atox1−/− mice. In cultured vascular smooth muscle cells, Ang II promotes translocation of Atox1 to the nucleus, thereby increasing SOD3 transcription by binding to Atox1 responsive element in the SOD3 promoter. Furthermore, Ang II increases Atox1 binding to the copper exporter ATP7A which obtains copper from Atox1 as well as translocation of ATP7A to plasma membranes where it colocalizes with SOD3. As its consequence, Ang II decreases vascular copper levels, which is inhibited in Atox1−/− mice. In summary, Atox1 functions to prevent Ang II-induced endothelial dysfunction and hyper-contraction in resistant vessels as well as hypertension in vivo by reducing extracellular O2•− levels via increasing vascular SOD3 expression and activity. PMID:22753205

Palladium and Platinum Nanoparticles Attenuate Aging-Like Skin Atrophy via Antioxidant Activity in Mice

PubMed Central

Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

2014-01-01

Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1 −/− mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1 −/− mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage. PMID:25333617

Palladium and platinum nanoparticles attenuate aging-like skin atrophy via antioxidant activity in mice.

PubMed

Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

2014-01-01

Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1-/- mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1-/- mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage.

Bee venom effects on ubiquitin proteasome system in hSOD1(G85R)-expressing NSC34 motor neuron cells.

PubMed

Kim, Seon Hwy; Jung, So Young; Lee, Kang-Woo; Lee, Sun Hwa; Cai, MuDan; Choi, Sun-Mi; Yang, Eun Jin

2013-07-18

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that results from a progressive loss of motor neurons. Familial ALS (fALS) is caused by missense mutations in Cu, Zn-superoxide dismutase 1 (SOD1) that frequently result in the accumulation of mutant protein aggregates that are associated with impairments in the ubiquitin-proteasome system (UPS). UPS impairment has been implicated in many neurological disorders. Bee venom (BV) extracted from honey bees has been used as a traditional medicine for treating inflammatory diseases and has been shown to attenuate the neuroinflammatory events that occur in a symptomatic ALS animal model. NSC34 cells were transiently transfected with a WT or G85R hSOD1-GFP construct for 24 hrs and then stimulated with 2.5 μg/ml BV for 24 hrs. To determine whether a SOD1 mutation affects UPS function in NSC34 cells, we examined proteasome activity and performed western blotting and immunofluorescence using specific antibodies, such as anti-misfolded SOD1, anti-ubiquitin, anti-GRP78, anti-LC3, and anti-ISG15 antibodies. We found that GFP-hSOD1G85R overexpression induced SOD1 inclusions and reduced proteasome activity compared with the overexpression of GFP alone in NSC34 motor neuronal cells. In addition, we also observed that BV treatment restored proteasome activity and reduced the accumulation of ubiquitinated and misfolded SOD1 in GFP-hSOD1G85R-overexpressing NSC34 motor neuronal cells. However, BV treatment did not activate the autophagic pathway in these cells. Our findings suggest that BV may rescue the impairment of the UPS in ALS models.

EXAFS analysis of a human Cu,Zn SOD isoform focused using non-denaturing gel electrophoresis

NASA Astrophysics Data System (ADS)

Chevreux, Sylviane; Solari, Pier Lorenzo; Roudeau, Stéphane; Deves, Guillaume; Alliot, Isabelle; Testemale, Denis; Hazemann, Jean Louis; Ortega, Richard

2009-11-01

Isoelectric point isoforms of a metalloprotein, copper-zinc superoxide dismutase (CuZnSOD), separated on electrophoresis gels were analyzed using X-ray Absorption Spectroscopy. Mutations of this protein are involved in familial cases of amyotrophic lateral sclerosis. The toxicity of mutants could be relied to defects in the metallation state. Our purpose is to establish analytical protocols to study metallation state of protein isoforms such as those from CuZnSOD. We previously highlighted differences in the copper oxidation state between CuZnSOD isoforms using XANES. Here, we present the first results for EXAFS analyses performed at Cu and Zn K-edge on the majoritary expressed isoform of human CuZnSOD separated on electrophoresis gels.

Preliminary neutron diffraction analysis of challenging human manganese superoxide dismutase crystals

DOE PAGES

Azadmanesh, Jahaun; Trickel, Scott R.; Weiss, Kevin L.; ...

2017-03-29

Superoxide dismutases (SODs) are enzymes that protect against oxidative stress by dismutation of superoxide into oxygen and hydrogen peroxide through cyclic reduction and oxidation of the active-site metal. The complete enzymatic mechanisms of SODs are unknown since data on the positions of hydrogen are limited. Here, we present, methods for large crystal growth and neutron data collection of human manganese SOD (MnSOD) using perdeuteration and the MaNDi beamline at Oak Ridge National Laboratory. Furthermore, The crystal from which the human MnSOD data set was obtained is the crystal with the largest unit-cell edge (240 Å) from which data have beenmore » collectedvianeutron diffraction to sufficient resolution (2.30 Å) where hydrogen positions can be observed.« less

Preliminary neutron diffraction analysis of challenging human manganese superoxide dismutase crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Azadmanesh, Jahaun; Trickel, Scott R.; Weiss, Kevin L.

Superoxide dismutases (SODs) are enzymes that protect against oxidative stress by dismutation of superoxide into oxygen and hydrogen peroxide through cyclic reduction and oxidation of the active-site metal. The complete enzymatic mechanisms of SODs are unknown since data on the positions of hydrogen are limited. Here, we present, methods for large crystal growth and neutron data collection of human manganese SOD (MnSOD) using perdeuteration and the MaNDi beamline at Oak Ridge National Laboratory. Furthermore, The crystal from which the human MnSOD data set was obtained is the crystal with the largest unit-cell edge (240 Å) from which data have beenmore » collectedvianeutron diffraction to sufficient resolution (2.30 Å) where hydrogen positions can be observed.« less

Tropical sod webworm (Lepidoptera: Crambidae): a pest of warm season Turfgrasses

USDA-ARS?s Scientific Manuscript database

Larvae of Herpetogramma species (commonly called webworms, sod webworms, or grass webworms) are widely distributed throughout North America, Eurasia, Australia, New Zealand, Central and South America. Tropical sod webworm Herpetogramma phaeopteralis (Guenée) larvae are among the most destructive pes...

Effects of Edaravone on Hippocampal Antioxidants in EL Mice.

PubMed

Baba, Asami; Kawakami, Yasuhiko; Saito, Kenichi; Murashima, Yoshiya L; Itoh, Yasuhiko

2016-01-01

The role of oxidative stress in susceptibility to seizures has been the focus of several recent studies. The aim of the present study was to evaluate the antiepileptic effects of the free radical scavenger edaravone on EL mice, a strain that is highly susceptible to convulsive seizures. EL mice were treated intraperitoneally with edaravone or saline for 1 week. The levels of reduced glutathione (GSH), oxidized glutathione (GSSG) and 3 isozymes of superoxide dismutase (SOD) (cytoplasmic copper- and zinc-containing SOD, extracellular SOD, and mitochondrial manganese-containing SOD) were measured in the hippocampus, and electroencephalograms (EEGs) were used to evaluate seizure sensitivity. Hippocampal levels of GSSG were lower in the edaravone group than in the untreated control group, and the GSH/GSSG ratio, Cu/Zn-SOD, and EC-SOD activities were higher in the edaravone group. Edaravone shortened the duration of interictal spike discharges and clinically suppressed epileptic seizures. Edaravone increases antioxidant potency and reduces seizure susceptibility in EL mice, making it a promising novel antiepileptic agent.

Oxidative Stress Response Tips the Balance in Aspergillus terreus Amphotericin B Resistance

PubMed Central

Blatzer, Michael; Posch, Wilfried; Steger, Marion; Binder, Ulrike; Lass-Flörl, Cornelia

2017-01-01

ABSTRACT In this study, we characterize the impact of antioxidative enzymes in amphotericin B (AmB)-resistant (ATR) and rare AmB-susceptible (ATS) clinical Aspergillus terreus isolates. We elucidate expression profiles of superoxide dismutase (SOD)- and catalase (CAT)-encoding genes, enzymatic activities of SODs, and superoxide anion production and signaling pathways involved in the oxidative stress response (OSR) in ATS and ATR strains under AmB treatment conditions. We show that ATR strains possess almost doubled basal SOD activity compared to that of ATS strains and that ATR strains exhibit an enhanced OSR, with significantly higher sod2 mRNA levels and significantly increased cat transcripts in ATR strains upon AmB treatment. In particular, inhibition of SOD and CAT proteins renders resistant isolates considerably susceptible to the drug in vitro. In conclusion, this study shows that SODs and CATs are crucial for AmB resistance in A. terreus and that targeting the OSR might offer new treatment perspectives for resistant species. PMID:28739793

Gene amplification at a locus encoding a putative Na+/H+ antiporter confers sodium and lithium tolerance in fission yeast.

PubMed Central

Jia, Z P; McCullough, N; Martel, R; Hemmingsen, S; Young, P G

1992-01-01

We have identified a new locus, sodium 2 (sod2) based on selection for increased LiCl tolerance in fission yeast, Schizosaccharomyces pombe. Tolerant strains have enhanced pH-dependent Na+ export capacity and sodium transport experiments suggest that the gene encodes an Na+/H+ antiport. The predicted sod2 gene product can be placed in the broad class of transporters which possess 12 hydrophobic transmembrane domains. The protein shows some sequence similarity to the human and bacterial Na+/H+ antiporters. Overexpression of sod2 increased Na+ export capacity and conferred sodium tolerance. Osmotolerance was not affected and sod2 cells were unaffected for growth in K+. In a sod2 disruption strain cells were incapable of exporting sodium. They were hypersensitive to Na+ or Li+ and could not grow under conditions that approximate pH7. The sod2 gene amplification could be selected stepwise and the degree of such amplification correlated with the level of Na+ or Li+ tolerance. Images PMID:1314171

Conjugates of Superoxide Dismutase 1 with Amphiphilic Poly(2-oxazoline) Block Copolymers for Enhanced Brain Delivery: Synthesis, Characterization and Evaluation in vitro and in vivo

PubMed Central

Tong, Jing; Yi, Xiang; Luxenhofer, Robert; Banks, William A.; Jordan, Rainer; Zimmerman, Matthew C.; Kabanov, Alexander V.

2013-01-01

Superoxide dismutase 1 (SOD1) efficiently catalyzes dismutation of superoxide but its poor delivery to the target sites in the body, such as brain, hinders its use as a therapeutic agent for superoxide-associated disorders. Here to enhance the delivery of SOD1 across the blood brain barrier (BBB) and in neurons the enzyme was conjugated with poly(2-oxazoline) (POx) block copolymers, P(MeOx-b-BuOx) or P(EtOx-b-BuOx), comprised of 1) hydrophilic 2-methyl-2-oxazoline (MeOx) or 2-ethyl-2-oxazoline (EtOx) and 2) hydrophobic 2-butyl-2-oxazoline (BuOx) repeating units. The conjugates contained from 2 to 3 POx chains joining the protein amino groups via cleavable -(ss)- or non-cleavable –(cc)- linkers at the BuOx block terminus. They retained 30% to 50% of initial SOD1 activity, were conformationally and thermally stable and assembled in 8 or 20 nm aggregates in aqueous solution. They had little if any toxicity to CATH.a neurons and displayed enhanced uptake in these neurons as compared to native or PEGylated SOD1. Of the two conjugates, SOD1-(cc)-P(MeOx-b-BuOx) and SOD1-(cc)-P(EtOx-b-BuOx) compared, the latter was entering cells 4 to 7 times faster and at 6 h colocalized predominantly with endoplasmic reticulum (41 ± 3%) and mitochondria (21 ± 2%). Colocalization with endocytosis markers and pathway inhibition assays suggested that it was internalized through lipid raft/caveolae, also employed by the P(EtOx-b-BuOx) copolymer. The SOD activity in cell lysates and ability to attenuate angiotensin II (Ang II)-induced superoxide in live cells were increased for this conjugate compared to SOD1 and PEG-SOD1. Studies in mice showed that SOD1-POx had ca. 1.75 times longer half-life in blood than native SOD1 (28.4 vs 15.9 min) and after i.v. administration penetrated the BBB significantly faster than albumin to accumulate in brain parenchyma. The conjugate maintained high stability both in serum and in brain (77% vs. 84% at 1 h post injection). Its amount taken up by the brain reached a maximum value of 0.08%ID/g (percent of the injected dose taken up per gram of brain) 4 h post injection. The entry of SOD1-(cc)-P(EtOx-b-BuOx) to the brain was mediated by a non-saturable mechanism. Altogether, SOD1-POx conjugates are promising candidates as macromolecular antioxidant therapies for superoxide-associated diseases such as Ang II induced neuro-cardiovascular diseases. PMID:23163230

Metallochaperone for Cu,Zn-superoxide dismutase (CCS) protein but not mRNA is higher in organs from copper-deficient mice and rats.

PubMed

Prohaska, Joseph R; Broderius, Margaret; Brokate, Bruce

2003-09-15

Cu,Zn-superoxide dismutase (SOD1) is an abundant metalloenzyme important in scavenging superoxide ions. Cu-deficient rats and mice have lower SOD1 activity and protein, possibly because apo-SOD1 is degraded faster than holo-SOD1. SOD1 interacts with and requires its metallochaperone CCS for donating copper. We produced dietary Cu deficiency in rodents to determine if the reduction in SOD1 was related to the level of its specific metallochaperone CCS. CCS levels determined by immunoblot were 2- to 3-fold higher in liver, heart, kidney, and brain from male Cu-deficient rats and mice under a variety of conditions. CCS was also higher in livers of Cu-deficient dams. Interestingly, CCS levels in brain of Cu-deficient mice were also higher even though SOD1 activity and protein were not altered, suggesting that the rise in CCS is correlated with altered Cu status rather than a direct result of lower SOD1. A DNA probe specific for rat CCS detected a single transcript by Northern blot hybridization with liver RNA. CCS mRNA levels in mouse and rat liver were not altered by dietary treatment. These results suggest a posttranscriptional mechanism for higher CCS protein when Cu is limiting in the cell, perhaps due to slower protein turnover. Elevation in CCS level is one of the most dramatic alterations in Cu binding proteins accompanying Cu deficiency and may be useful to assess Cu status.

Identification of copper/zinc superoxide dismutase as a novel nitric oxide-regulated gene in rat glomerular mesangial cells and kidneys of endotoxemic rats.

PubMed

Frank, S; Zacharowski, K; Wray, G M; Thiemermann, C; Pfeilschifter, J

1999-05-01

To define the mechanism of nitric oxide (NO) action in the glomerulus, we attempted to identify genes that are regulated by NO in rat glomerular mesangial cells. We identified a Cu/Zn superoxide dismutase (SOD) that was strongly induced in these cells by treatment with S-nitroso-glutathione as a NO-donating agent. Bacterial lipopolysaccharide (LPS) acutely decreased Cu/Zn SOD mRNA levels. The LPS-mediated decrease in Cu/Zn SOD is reversed by endogenously produced NO, as LPS also induced a delayed strong iNOS expression in these cells in vitro, which is accompanied by increased Cu/Zn SOD expression. NO dependency of Cu/Zn SOD mRNA recovery could be demonstrated by inhibition of this process by L-NG-monomethylarginine, an inhibitor of NOS enzymatic activity. To demonstrate the in vivo relevance of our observations, we have chosen LPS-treated rats as a model for induction of a systemic inflammatory response. In these animals, we demonstrate a direct coupling of Cu/Zn SOD expression levels to the presence of NO, as Cu/Zn SOD mRNA levels declined during acute inflammation in the presence of a selective inhibitor of iNOS. We propose that the up-regulation of Cu/Zn SOD by endogenous NO may serve as an adaptive, protective mechanism to prevent the formation of toxic quantities of peroxynitrite in conditions associated with iNOS induction during endotoxic shock.

SOD-1 expression in pig coronary arterioles is increased by exercise training.

PubMed

Rush, J W; Laughlin, M H; Woodman, C R; Price, E M

2000-11-01

Coronary arterioles of exercise-trained (EX) pigs have enhanced nitric oxide (NO.)-dependent dilation. Evidence suggests that the biological half-life of NO. depends in part on the management of the superoxide anion. The purpose of this study was to test the hypothesis that expression of cytosolic copper/zinc-dependent superoxide dismutase (SOD)-1 is increased in coronary arterioles as a result of exercise training. Male Yucatan pigs either remained sedentary (SED, n = 4) or were EX (n = 4) on a motorized treadmill for 16-20 wk. Individual coronary arterioles ( approximately 100-microm unpressurized internal diameter) were dissected and frozen. Coronary arteriole SOD-1 protein (via immunoblots) increased as a result of exercise training (2.16 +/- 0.35 times SED levels) as did SOD-1 enzyme activity (measured via inhibition of pyrogallol autooxidation; approximately 75% increase vs. SED). In addition, SOD-1 mRNA levels (measured via RT-PCR) were higher in EX arterioles (1.68 +/- 0.16 times the SED levels). There were no effects of exercise training on the levels of SOD-2 (mitochondrial), catalase, or p67(phox) proteins. Thus chronic aerobic exercise training selectively increases the levels of SOD-1 mRNA, protein, and enzymatic activity in porcine coronary arterioles. Increased SOD-1 could contribute to the enhanced NO.-dependent dilation previously observed in EX porcine coronary arterioles by improving management of superoxide in the vascular cell environment, thus prolonging the biological half-life of NO.

Cloning and characterization of iron-superoxide dismutase in Antarctic yeast strain Rhodotorula mucilaginosa AN5.

PubMed

Kan, Guangfeng; Wen, Hua; Wang, Xiaofei; Zhou, Ting; Shi, Cuijuan

2017-08-01

A novel superoxide dismutase gene from Antarctic yeast Rhodotorula mucilaginosa AN5 was cloned, sequenced, and then expressed in Escherichia coli. The R. mucilaginosa AN5 SOD (RmFeSOD) gene was 639 bp open reading frame in length, which encoded a protein of 212 amino acids with a deduced molecular mass of 23.5 kDa and a pI of 7.89. RmFeSOD was identified as iron SOD type with a natural status of homodimer. The recombinant RmFeSOD showed good pH stability in the pH 1.0-9.0 after 1 h incubation. Meanwhile, it was found to behave relatively high thermostability, and maintained more than 80% activity at 50 °C for 1 h. By addition of 1 mM metal ions, the enzyme activity increased by Zn 2+ , Cu 2+ , Mn 2+ , and Fe 3+ , and inhibited only by Mg 2+ . RmFeSOD showed relatively low tolerance to some compounds, such as PMSF, SDS, Tween-80, Triton X-100, DMSO, β-ME, and urea. However, DTT showed no inhibition to enzyme activity. Using copper stress experiment, the RmFeSOD recombinant E. coli exhibited better growth than non-recombinant bacteria, which revealed that RmFeSOD might play an important role in the adaptability of heavy metals. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Focal dysfunction of the proteasome: a pathogenic factor in a mouse model of amyotrophic lateral sclerosis.

PubMed

Kabashi, Edor; Agar, Jeffrey N; Taylor, David M; Minotti, Sandra; Durham, Heather D

2004-06-01

Mutations in the Cu/Zn-superoxide dismutase (SOD-1) gene are responsible for a familial form of amyotrophic lateral sclerosis (fALS). The present study demonstrated impaired proteasomal function in the lumbar spinal cord of transgenic mice expressing human SOD-1 with the ALS-causing mutation G93A (SOD-1(G93A)) compared to non-transgenic littermates (LM) and SOD-1(WT) transgenic mice. Chymotrypsin-like activity was decreased as early as 45 days of age. By 75 days, chymotrypsin-, trypsin-, and caspase-like activities of the proteasome were impaired, at about 50% of control activity in lumbar spinal cord, but unchanged in thoracic spinal cord and liver. Both total and specific activities of the proteasome were reduced to a similar extent, indicating that a change in proteasome function, rather than a decrease in proteasome levels, had occurred. Similar decreases of total and specific activities of the proteasome were observed in NIH 3T3 cell lines expressing fALS mutants SOD-1(G93A) and SOD-1(G41S), but not in SOD-1(WT) controls. Although overall levels of proteasome were maintained in spinal cord of SOD-1(G93A) transgenic mice, the level of 20S proteasome was substantially reduced in lumbar spinal motor neurons relative to the surrounding neuropil. It is concluded that impairment of the proteasome is an early event and contributes to ALS pathogenesis.

Is SOD2 Ala16Val Polymorphism Associated with Migraine with Aura Phenotype?

PubMed Central

Barbanti, Piero; De Marchis, Maria Laura; Egeo, Gabriella; Aurilia, Cinzia; Fofi, Luisa; Ialongo, Cristiano; Valente, Maria Giovanna; Ferroni, Patrizia; Della-Morte, David; Guadagni, Fiorella

2015-01-01

Abstract Several studies suggest a role of oxidative stress in the physiopathology of migraine, particularly in the form with aura. In a case-control study, we investigated the association between migraine and superoxide dismutase 1 (SOD1) and superoxide dismutase 2 (SOD2) genes in a cohort of 490 consecutive unrelated Caucasian migraineurs (migraine with aura [MwA], n=107; migraine without aura [MwoA], n=246; chronic migraine [CM], n=137) and 246 healthy controls recruited at our Headache and Pain Unit and stored in the Interinstitutional Multidisciplinary BioBank (BioBIM). Migraine phenotype was carefully detailed using face-to-face interviews. We examined polymorphisms of SOD1 gene (A/C substitution—rs2234694) and SOD2 gene (C/T transition—rs4880—Ala16Val). The rs4880 TT (Val/Val) genotype was associated (p=0.042) with the presence of unilateral cranial autonomic symptoms (UAs) in MwA patients. We also found a mild correlation between SOD2 rs4880 genotype and the type of acute migraine treatment (p=0.048) in MwA patients. Our findings suggest that SOD2 is a disease-modifier gene influencing oxidative mechanisms in MwA. These observations lead to the hypothesis that SOD2 polymorphism may cause a defective control of the oxidative phenomena linked to cortical spreading depression, the neurophysiological hallmark of migraine aura, causing an overstimulation of trigeminal neurons and UAs triggering. Antioxid. Redox Signal. 22, 275–279. PMID:25295643

Effects of decontamination of the oropharynx and intestinal tract on antibiotic resistance in ICUs: a randomized clinical trial.

PubMed

Oostdijk, Evelien A N; Kesecioglu, Jozef; Schultz, Marcus J; Visser, Caroline E; de Jonge, Evert; van Essen, Einar H R; Bernards, Alexandra T; Purmer, Ilse; Brimicombe, Roland; Bergmans, Dennis; van Tiel, Frank; Bosch, Frank H; Mascini, Ellen; van Griethuysen, Arjanne; Bindels, Alexander; Jansz, Arjan; van Steveninck, Fred A L; van der Zwet, Wil C; Fijen, Jan Willem; Thijsen, Steven; de Jong, Remko; Oudbier, Joke; Raben, Adrienne; van der Vorm, Eric; Koeman, Mirelle; Rothbarth, Philip; Rijkeboer, Annemieke; Gruteke, Paul; Hart-Sweet, Helga; Peerbooms, Paul; Winsser, Lex J; van Elsacker-Niele, Anne-Marie W; Demmendaal, Kees; Brandenburg, Afke; de Smet, Anne Marie G A; Bonten, Marc J M

2014-10-08

Selective decontamination of the digestive tract (SDD) and selective oropharyngeal decontamination (SOD) are prophylactic antibiotic regimens used in intensive care units (ICUs) and associated with improved patient outcome. Controversy exists regarding the relative effects of both measures on patient outcome and antibiotic resistance. To compare the effects of SDD and SOD, applied as unit-wide interventions, on antibiotic resistance and patient outcome. Pragmatic, cluster randomized crossover trial comparing 12 months of SOD with 12 months of SDD in 16 Dutch ICUs between August 1, 2009, and February 1, 2013. Patients with an expected length of ICU stay longer than 48 hours were eligible to receive the regimens, and 5881 and 6116 patients were included in the clinical outcome analysis for SOD and SDD, respectively. Intensive care units were randomized to administer either SDD or SOD. Unit-wide prevalence of antibiotic-resistant gram-negative bacteria. Secondary outcomes were day-28 mortality, ICU-acquired bacteremia, and length of ICU stay. In point-prevalence surveys, prevalences of antibiotic-resistant gram-negative bacteria in perianal swabs were significantly lower during SDD compared with SOD; for aminoglycoside resistance, average prevalence was 5.6% (95% CI, 4.6%-6.7%) during SDD and 11.8% (95% CI, 10.3%-13.2%) during SOD (P < .001). During both interventions the prevalence of rectal carriage of aminoglycoside-resistant gram-negative bacteria increased 7% per month (95% CI, 1%-13%) during SDD (P = .02) and 4% per month (95% CI, 0%-8%) during SOD (P = .046; P = .40 for difference). Day 28-mortality was 25.4% and 24.1% during SOD and SDD, respectively (adjusted odds ratio, 0.96 [95% CI, 0.88-1.06]; P = .42), and there were no statistically significant differences in other outcome parameters or between surgical and nonsurgical patients. Intensive care unit-acquired bacteremia occurred in 5.9% and 4.6% of the patients during SOD and SDD, respectively (odds ratio, 0.77 [95% CI, 0.65-0.91]; P = .002; number needed to treat, 77). Unit-wide application of SDD and SOD was associated with low levels of antibiotic resistance and no differences in day-28 mortality. Compared with SOD, SDD was associated with lower rectal carriage of antibiotic-resistant gram-negative bacteria and ICU-acquired bacteremia but a more pronounced gradual increase in aminoglycoside-resistant gram-negative bacteria. trialregister.nlIdentifier: NTR1780.

Superoxide Dismutase Protects Cells from DNA Damage Induced by Trivalent Methylated Arsenicals

EPA Science Inventory

Superoxide dismutase (SOD) catalyzes the conversion of superoxide to hydrogen peroxide. Heterozygous mice of strain B6; 129S7-Sod1(tm1Leb)/J were obtained from Jackson Laboratories and bred to produce offspring that were heterozygous (+/Sod1(tm1Leb)), homozygous wild-type (+/+), ...

In vivo kinetic approach reveals slow SOD1 turnover in the CNS

PubMed Central

Crisp, Matthew J.; Mawuenyega, Kwasi G.; Patterson, Bruce W.; Reddy, Naveen C.; Chott, Robert; Self, Wade K.; Weihl, Conrad C.; Jockel-Balsarotti, Jennifer; Varadhachary, Arun S.; Bucelli, Robert C.; Yarasheski, Kevin E.; Bateman, Randall J.; Miller, Timothy M.

2015-01-01

Therapeutic strategies that target disease-associated transcripts are being developed for a variety of neurodegenerative syndromes. Protein levels change as a function of their half-life, a property that critically influences the timing and application of therapeutics. In addition, both protein kinetics and concentration may play important roles in neurodegeneration; therefore, it is essential to understand in vivo protein kinetics, including half-life. Here, we applied a stable isotope-labeling technique in combination with mass spectrometric detection and determined the in vivo kinetics of superoxide dismutase 1 (SOD1), mutation of which causes amyotrophic lateral sclerosis. Application of this method to human SOD1-expressing rats demonstrated that SOD1 is a long-lived protein, with a similar half-life in both the cerebral spinal fluid (CSF) and the CNS. Additionally, in these animals, the half-life of SOD1 was longest in the CNS when compared with other tissues. Evaluation of this method in human subjects demonstrated successful incorporation of the isotope label in the CSF and confirmed that SOD1 is a long-lived protein in the CSF of healthy individuals. Together, the results of this study provide important insight into SOD1 kinetics and support application of this technique to the design and implementation of clinical trials that target long-lived CNS proteins. PMID:26075819

Sod2 haploinsufficiency does not accelerate aging of telomere dysfunctional mice

PubMed Central

Guachalla, Luis Miguel; Ju, Zhenyu; Koziel, Rafal; von Figura, Guido; Song, Zhangfa; Fusser, Markus; Epe, Bernd; Jansen-Dűrr, Pidder; Rudolph, K. Lenhard

2009-01-01

Telomere shortening represents a causal factor of cellular senescence. At the same time, several lines of evidence indicate a pivotal role of oxidative DNA damage for the aging process in vivo. A causal connection between the two observations was suggested by experiments showing accelerated telomere shorting under conditions of oxidative stress in cultured cells, but has never been studied in vivo. We therefore have analysed whether an increase in mitochondrial derived oxidative stress in response to heterozygous deletion of superoxide dismutase (Sod2+/-) would exacerbate aging phenotypes in telomere dysfunctional (mTerc-/-) mice. Heterozygous deletion of Sod2 resulted in reduced SOD2 protein levels and increased oxidative stress in aging telomere dysfunctional mice, but this did not lead to an increase in basal levels of oxidative nuclear DNA damage, an accumulation of nuclear DNA breaks, or an increased rate of telomere shortening in the mice. Moreover, heterozygous deletion of Sod2 did not accelerate the depletion of stem cells and the impairment in organ maintenance in aging mTerc-/- mice. In agreement with these observations, Sod2 haploinsufficiency did not lead to a further reduction in lifespan of mTerc-/- mice. Together, these results indicate that a decrease in SOD2-dependent antioxidant defence does not exacerbate aging in the context of telomere dysfunction. PMID:20195488

Genetic disruption of SOD1 gene causes glucose intolerance and impairs β-cell function.

PubMed

Muscogiuri, Giovanna; Salmon, Adam B; Aguayo-Mazzucato, Cristina; Li, Mengyao; Balas, Bogdan; Guardado-Mendoza, Rodolfo; Giaccari, Andrea; Reddick, Robert L; Reyna, Sara M; Weir, Gordon; Defronzo, Ralph A; Van Remmen, Holly; Musi, Nicolas

2013-12-01

Oxidative stress has been associated with insulin resistance and type 2 diabetes. However, it is not clear whether oxidative damage is a cause or a consequence of the metabolic abnormalities present in diabetic subjects. The goal of this study was to determine whether inducing oxidative damage through genetic ablation of superoxide dismutase 1 (SOD1) leads to abnormalities in glucose homeostasis. We studied SOD1-null mice and wild-type (WT) littermates. Glucose tolerance was evaluated with intraperitoneal glucose tolerance tests. Peripheral and hepatic insulin sensitivity was quantitated with the euglycemic-hyperinsulinemic clamp. β-Cell function was determined with the hyperglycemic clamp and morphometric analysis of pancreatic islets. Genetic ablation of SOD1 caused glucose intolerance, which was associated with reduced in vivo β-cell insulin secretion and decreased β-cell volume. Peripheral and hepatic insulin sensitivity were not significantly altered in SOD1-null mice. High-fat diet caused glucose intolerance in WT mice but did not further worsen the glucose intolerance observed in standard chow-fed SOD1-null mice. Our findings suggest that oxidative stress per se does not play a major role in the pathogenesis of insulin resistance and demonstrate that oxidative stress caused by SOD1 ablation leads to glucose intolerance secondary to β-cell dysfunction.

Genetic Disruption of SOD1 Gene Causes Glucose Intolerance and Impairs β-Cell Function

PubMed Central

Muscogiuri, Giovanna; Salmon, Adam B.; Aguayo-Mazzucato, Cristina; Li, Mengyao; Balas, Bogdan; Guardado-Mendoza, Rodolfo; Giaccari, Andrea; Reddick, Robert L.; Reyna, Sara M.; Weir, Gordon; DeFronzo, Ralph A.; Van Remmen, Holly; Musi, Nicolas

2013-01-01

Oxidative stress has been associated with insulin resistance and type 2 diabetes. However, it is not clear whether oxidative damage is a cause or a consequence of the metabolic abnormalities present in diabetic subjects. The goal of this study was to determine whether inducing oxidative damage through genetic ablation of superoxide dismutase 1 (SOD1) leads to abnormalities in glucose homeostasis. We studied SOD1-null mice and wild-type (WT) littermates. Glucose tolerance was evaluated with intraperitoneal glucose tolerance tests. Peripheral and hepatic insulin sensitivity was quantitated with the euglycemic-hyperinsulinemic clamp. β-Cell function was determined with the hyperglycemic clamp and morphometric analysis of pancreatic islets. Genetic ablation of SOD1 caused glucose intolerance, which was associated with reduced in vivo β-cell insulin secretion and decreased β-cell volume. Peripheral and hepatic insulin sensitivity were not significantly altered in SOD1-null mice. High-fat diet caused glucose intolerance in WT mice but did not further worsen the glucose intolerance observed in standard chow–fed SOD1-null mice. Our findings suggest that oxidative stress per se does not play a major role in the pathogenesis of insulin resistance and demonstrate that oxidative stress caused by SOD1 ablation leads to glucose intolerance secondary to β-cell dysfunction. PMID:24009256

Biodegradable polycaprolactone (PCL) nanosphere encapsulating superoxide dismutase and catalase enzymes.

PubMed

Singh, Sushant; Singh, Abhay Narayan; Verma, Anil; Dubey, Vikash Kumar

2013-12-01

Biodegradable polycaprolactone (PCL) nanosphere encapsulating superoxide dismutase (SOD) and catalase (CAT) were successfully synthesized using double emulsion (w/o/w) solvent evaporation technique. Characterization of the nanosphere using dynamic light scattering, field emission scanning electron microscope, and Fourier transform infrared spectroscopy revealed a spherical-shaped nanosphere in a size range of 812 ± 64 nm with moderate protein encapsulation efficiency of 55.42 ± 3.7 % and high in vitro protein release. Human skin HaCat cells were used for analyzing antioxidative properties of SOD- and CAT-encapsulated PCL nanospheres. Oxidative stress condition in HaCat cells was optimized with exposure to hydrogen peroxide (H2O2; 1 mM) as external stress factor and verified through reactive oxygen species (ROS) analysis using H2DCFDA dye. PCL nanosphere encapsulating SOD and CAT together indicated better antioxidative defense against H2O2-induced oxidative stress in human skin HaCat cells in comparison to PCL encapsulating either SOD or CAT alone as well as against direct supplement of SOD and CAT protein solution. Increase in HaCat cells SOD and CAT activities after treatment hints toward uptake of PCL nanosphere into the human skin HaCat cells. The result signifies the role of PCL-encapsulating SOD and CAT nanosphere in alleviating oxidative stress.

The structure of the Caenorhabditis elegans manganese superoxide dismutase MnSOD-3-azide complex

DOE PAGES

Hunter, Gary J.; Trinh, Chi H.; Bonetta, Rosalin; ...

2015-08-27

C. elegans MnSOD-3 has been implicated in the longevity pathway and its mechanism of catalysis is relevant to the aging process and carcinogenesis. The structures of MnSOD-3 provide unique crystallographic evidence of a dynamic region of the tetrameric interface (residues 41–54). We have determined the structure of the MnSOD-3-azide complex to 1.77-Å resolution. The analysis of this complex shows that the substrate analog, azide, binds end-on to the manganese center as a sixth ligand and that it ligates directly to a third and new solvent molecule also positioned within interacting distance to the His30 and Tyr34 residues of the substratemore » access funnel. This is the first structure of a eukaryotic MnSOD-azide complex that demonstrates the extended, uninterrupted hydrogen-bonded network that forms a proton relay incorporating three outer sphere solvent molecules, the substrate analog, the gateway residues, Gln142, and the solvent ligand. This configuration supports the formation and release of the hydrogen peroxide product in agreement with the 5-6-5 catalytic mechanism for MnSOD. The high product dissociation constant k₄ of MnSOD-3 reflects low product inhibition making this enzyme efficient even at high levels of superoxide.« less

Superoxide dismutases in chronic gastritis.

PubMed

Švagelj, Dražen; Terzić, Velimir; Dovhanj, Jasna; Švagelj, Marija; Cvrković, Mirta; Švagelj, Ivan

2016-04-01

Human gastric diseases have shown significant changes in the activity and expression of superoxide dismutase (SOD) isoforms. The aim of this study was to detect Mn-SOD activity and expression in the tissue of gastric mucosa, primarily in chronic gastritis (immunohistochemical Helicobacter pylori-negative gastritis, without other pathohistological changes) and to evaluate their possible connection with pathohistological diagnosis. We examined 51 consecutive outpatients undergoing endoscopy for upper gastrointestinal symptoms. Patients were classified based on their histopathological examinations and divided into three groups: 51 patients (archive samples between 2004-2009) with chronic immunohistochemical Helicobacter pylori-negative gastritis (mononuclear cells infiltration were graded as absent, moderate, severe) divided into three groups. Severity of gastritis was graded according to the updated Sydney system. Gastric tissue samples were used to determine the expression of Mn-SOD with anti-Mn-SOD Ab immunohistochemically. The Mn-SOD expression was more frequently present in specimens with severe and moderate inflammation of gastric mucosa than in those with normal mucosa. In patients with normal histological finding, positive immunoreactivity of Mn-SOD was not found. Our results determine the changes in Mn-SOD expression occurring in the normal gastric mucosa that had undergone changes in the intensity of chronic inflammatory infiltrates in the lamina propria. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Role of disulfide cross-linking of mutant SOD1 in the formation of inclusion-body-like structures.

PubMed

Roberts, Brittany L T; Patel, Kinaree; Brown, Hilda H; Borchelt, David R

2012-01-01

Pathologic aggregates of superoxide dismutase 1 (SOD1) harboring mutations linked to familial amyotrophic lateral sclerosis (fALS) have been shown to contain aberrant intermolecular disulfide cross-links. In prior studies, we observed that intermolecular bonding was not necessary in the formation of detergent- insoluble SOD1 complexes by mutant SOD1, but we were unable to assess whether this type of bonding may be important for pathologic inclusion formation. In the present study, we visually assess the formation of large inclusions by fusing mutant SOD1 to yellow fluorescent protein (YFP). Experimental constructs possessing mutations at all cysteine residues in SOD1 (sites 6, 57, 111, and 146 to F,S,Y,R or G,S,Y,R, respectively) were shown to maintain a high propensity of inclusion formation despite the inability to form disulfide cross-links. Interestingly, although aggregates form when all cysteines were mutated, double mutants of the ALS mutation C6G with an experimental mutation C111S exhibited low aggregation propensity. Overall, this study is an extension of previous work demonstrating that cysteine residues in mutant SOD1 play a role in modulating aggregation and that intermolecular disulfide bonds are not required to produce large intracellular inclusion-like structures.

Dimethyl sulfoxide induces oxidative stress in the yeast Saccharomyces cerevisiae.

PubMed

Sadowska-Bartosz, Izabela; Pączka, Aleksandra; Mołoń, Mateusz; Bartosz, Grzegorz

2013-12-01

Dimethyl sulfoxide (DMSO) is used as a cryoprotectant for the preservation of cells, including yeast, and as a solvent for chemical compounds. We report that DMSO induces oxidative stress in the yeast. Saccharomyces cerevisiae wt strain EG-103 and its mutants Δsod1, Δsod2, and Δsod1 Δsod2 were used. Yeast were subjected to the action of 1-14% DMSO for 1 h at 28 °C. DMSO induced a concentration-dependent inhibition of yeast growth, the effect being more pronounced for mutants devoid of SOD (especially Δsod1 Δsod2). Cell viability was compromised. DMSO-concentration-dependent activity loss of succinate dehydrogenase, a FeS enzyme sensitive to oxidative stress, was observed. DMSO enhanced formation of reactive oxygen species, estimated with dihydroethidine in a concentration-dependent manner, the effect being again more pronounced in mutants devoid of superoxide dismutases. The content of cellular glutathione was increased with increasing DMSO concentrations, which may represent a compensatory response. Membrane fluidity, estimated by fluorescence polarization of DPH, was decreased by DMSO. These results demonstrate that DMSO, although generally considered to be antioxidant, induces oxidative stress in yeast cells. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

In vivo kinetic approach reveals slow SOD1 turnover in the CNS.

PubMed

Crisp, Matthew J; Mawuenyega, Kwasi G; Patterson, Bruce W; Reddy, Naveen C; Chott, Robert; Self, Wade K; Weihl, Conrad C; Jockel-Balsarotti, Jennifer; Varadhachary, Arun S; Bucelli, Robert C; Yarasheski, Kevin E; Bateman, Randall J; Miller, Timothy M

2015-07-01

Therapeutic strategies that target disease-associated transcripts are being developed for a variety of neurodegenerative syndromes. Protein levels change as a function of their half-life, a property that critically influences the timing and application of therapeutics. In addition, both protein kinetics and concentration may play important roles in neurodegeneration; therefore, it is essential to understand in vivo protein kinetics, including half-life. Here, we applied a stable isotope-labeling technique in combination with mass spectrometric detection and determined the in vivo kinetics of superoxide dismutase 1 (SOD1), mutation of which causes amyotrophic lateral sclerosis. Application of this method to human SOD1-expressing rats demonstrated that SOD1 is a long-lived protein, with a similar half-life in both the cerebral spinal fluid (CSF) and the CNS. Additionally, in these animals, the half-life of SOD1 was longest in the CNS when compared with other tissues. Evaluation of this method in human subjects demonstrated successful incorporation of the isotope label in the CSF and confirmed that SOD1 is a long-lived protein in the CSF of healthy individuals. Together, the results of this study provide important insight into SOD1 kinetics and support application of this technique to the design and implementation of clinical trials that target long-lived CNS proteins.

Molecular interaction of triclosan with superoxide dismutase (SOD) reveals a potentially toxic mechanism of the antimicrobial agent.

PubMed

Mi, Chenyu; Teng, Yue; Wang, Xiaofang; Yu, Hongyan; Huang, Zhenxing; Zong, Wansong; Zou, Luyi

2018-05-30

In this article, the interaction mechanism between the superoxide dismutase (SOD) and the triclosan (TCS), a kind of antimicrobial agent which is of widely application with potential effects both on environment and human health, was explored through a series of spectroscopic methods, animal experiment and the molecular docking simulation. The negative free energy change ∆G, enthalpy change (∆H = 162.21 kJmol -1 ) and entropy change (∆S = 615 Jmol -1 K -1 ) demonstrated that TCS could combine with SOD spontaneously through hydrophobic interaction to form a complex. The binding constants of K a293 and K a313 were 1.706 × 10 3 and 1.2 × 10 5 Lmol -1 , respectively. Furthermore, the interaction could also influence the skeleton structure and secondary contents of SOD. The molecular docking analysis revealed the TCS located between two subunits of SOD, and there was a hydrogen bond between TCS and the residue Asn51 of SOD, which influenced the structure of protein and resulted in a decrease of enzyme activity. This work could help understand the interaction mechanism between SOD and TCS. Moreover, it could also be used to consult for toxicity assessment of TCS at molecular level. Copyright © 2018 Elsevier Inc. All rights reserved.

A novel nanobiotherapeutic poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] with no cardiac toxicity for the resuscitation of a rat model with 90 minutes of sustained severe hemorrhagic shock with loss of 2/3 blood volume

PubMed Central

Bian, Yuzhu; Chang, Thomas Ming Swi

2015-01-01

Abstract We crosslink hemoglobin (Hb), superoxide dismutase (SOD), catalase (CAT), and carbonic anhydrase (CA) to form a soluble polyHb-SOD-CAT-CA nanobiotechnological complex. The obtained product is a soluble complex with three enhanced red blood cell (RBC) functions and without blood group antigens. In the present study, 2/3 of blood volume was removed to result in 90-min hemorrhagic shock at mean arterial blood pressure (MAP) of 30 mmHg. This was followed by the reinfusion of different resuscitation fluids, then followed for another 60 min. PolyHb-SOD-CAT-CA maintained the MAP at 87.5 ± 5 mmHg as compared with 3 volumes of lactated Ringer's solution, 43.3 ± 2.8 mmHg; blood, 91.3 ± 3.6 mmHg; polyHb-SOD-CAT, 86.0 ± 4.6 mmHg; poly stroma-free hemolysate (polySFHb), 85.0 ± 2.5 mmHg; and polyHb, 82.6 ± 3.5 mmHg. PolyHb-SOD-CAT-CA was superior to the blood and other fluids based on the following criteria. PolyHb-SOD-CAT-CA reduced tissue pCO2 from 98 ± 4.5 mmHg to 68.6 ± 3 mmHg. This was significantly (p < 0.05) more effective than lactated Ringer's solution (98 ± 4.5 mmHg), polyHb (90.1 ± 4.0 mmHg), polyHb-SOD-CAT (90.9 ± 1.4 mmHg), blood (79.1 ± 4.7 mmHg), and polySFHb (77 ± 5 mmHg). PolyHb-SOD-CAT-CA reduced the elevated ST level to 21.7 ± 6.7% and is significantly (< 0.05) better than polyHb (57.7 ± 8.7%), blood (39.1 ± 1.5%), polySFHb (38.3% ± 2.1%), polyHb-SOD-CAT (27.8 ± 5.6%), and lactated Ringer's solution (106 ± 3.1%). The plasma cardiac troponin T (cTnT) level of polyHb-SOD-CAT-CA group was significantly (P < 0.05) lower than that of all the other groups. PolyHb-SOD-CAT-CA reduced plasma lactate level from 18 ± 2.3 mM/L to 6.9 ± 0.3 mM/L. It was significantly more effective (P < 0.05) than lactated Ringer's solution (12.4 ± 0.6 mM/L), polyHb (9.6 ± 0.7 mM/L), blood (8.1 ± 0.2 mM/L), polySFHb (8.4 ± 0.1 mM/L), and polyHb-SOD-CAT (7.6 ± 0.3 mM/L). PolyHb-SOD-CAT-CA can be stored for 320 days at room temperature. Lyophilized poly-Hb-SOD-CAT-CA can be heat pasteurized at 68F for 2 h. This can be important if there is a need to inactivate human immunodeficiency virus, Ebola virus, and other infectious organisms. PMID:25297052

DNA strand breaks and TDP-43 mislocation are absent in the murine hSOD1G93A model of amyotrophic lateral sclerosis in vivo and in vitro

PubMed Central

Witte, Otto W.; Grosskreutz, Julian

2017-01-01

Mutations in the human Cu/Zn superoxide dismutase type-1 (hSOD1) gene are common in familial amyotrophic lateral sclerosis (fALS). The pathophysiology has been linked to, e.g., organelle dysfunction, RNA metabolism and oxidative DNA damage conferred by SOD1 malfunction. However, apart from metabolically evoked DNA oxidation, it is unclear whether severe genotoxicity including DNA single-strand breaks (SSBs) and double-strand breaks (DSBs), originates from loss of function of nuclear SOD1 enzyme. Factors that endogenously interfere with DNA integrity and repair complexes in hSOD1-mediated fALS remain similarly unexplored. In this regard, uncontrolled activation of transposable elements (TEs) might contribute to DNA disintegration and neurodegeneration. The aim of this study was to elucidate the role of the fALS-causing hSOD1G93A mutation in the generation of severe DNA damage beyond well-characterized DNA base oxidation. Therefore, DNA damage was assessed in spinal tissue of hSOD1G93A-overexpressing mice and in corresponding motor neuron-enriched cell cultures in vitro. Overexpression of the hSOD1G93A locus did not change the threshold for severe DNA damage per se. We found that levels of SSBs and DSBs were unaltered between hSOD1G93A and control conditions, as demonstrated in post-mitotic motor neurons and in astrocytes susceptible to replication-dependent DNA breakage. Analogously, parameters indicative of DNA damage response processes were not activated in vivo or in vitro. Evidence for a mutation-related elevation in TE activation was not detected, in accordance with the absence of TAR DNA binding protein 43 (TDP-43) proteinopathy in terms of cytoplasmic mislocation or nuclear loss, as nuclear TDP-43 is supposed to silence TEs physiologically. Conclusively, the superoxide dismutase function of SOD1 might not be required to preserve DNA integrity in motor neurons, at least when the function of TDP-43 is unaltered. Our data establish a foundation for further investigations addressing functional TDP-43 interaction with ALS-relevant genetic mutations. PMID:28832631

Mitochondrial MnSOD mRNA expression in human chorioamniotic membranes and its association with labor, inflammation and infection

PubMed Central

Than, Nandor Gabor; Romero, Roberto; Tarca, Adi L.; Draghici, Sorin; Erez, Offer; Chaiworapongsa, Tinnakorn; Kim, Yeon Mee; Kim, Sun Kwon; Vaisbuch, Edi; Tromp, Gerard

2010-01-01

Objective Human parturition is characterized by the activation of genes involved in acute inflammatory in the fetal membranes. Manganese superoxide dismutase (MnSOD) is a mitochondrial enzyme that scavenges reactive oxygen species (ROS). MnSOD is up-regulated in sites of inflammation and has an important role in the down-regulation of acute inflammatory processes. Therefore, the aim of this study was to determine the differences in MnSOD mRNA expression in the fetal membranes in patients with term and preterm labor as well as in acute chorioamnionitis. Study design Fetal membranes were obtained from patients in the following groups: 1) term not in labor (n=29); 2) term in labor (n=29); 3) spontaneous preterm labor with intact mebranes (n=16); 4) PTL with histological chorioamnionitis (n=12); 5) preterm prelabor rupture of membranes (PPROM; n=17); and 6) PPROM with histological chorioamnionitis (n=21). MnSOD mRNA expression in the membranes was determined by quantitative real-time RT-PCR. Results 1) MnSOD mRNA expression was higher in the fetal membranes of patients at term in labor than those not in labor (2.4-fold; p=0.02); 2) the amount of MnSOD mRNA in the fetal membranes was higher in PTL than in term labor or in PPROM (7.2-fold, p=0.03; 3.2-fold, p=0.03, respectively); 3) MnSOD mRNA expression was higher when histological chorioamnionitis was present both among patients with PPROM (3.8-fold, p=0.02) and with PTL (5.4-fold, p=0.02) than in patients with these conditions without histological chorioamnionitis; 4) expression of MnSOD mRNA was higher in PTL with chorioamnionitis than in PPROM with chorioamnionitis (4.3-fold, p=0.03); Conclusion The increase in MnSOD mRNA expression by fetal membranes in term labor and in histological chorioamnionitis in PTL and PPROM suggests that the fetus deploys anti-oxidant mechanisms to constrain the inflammatory processes in the chorioamniotic membranes. PMID:19900038

Effects of environmental enrichment on the amyotrophic lateral sclerosis mouse model.

PubMed

Sorrells, A D; Corcoran-Gomez, K; Eckert, K A; Fahey, A G; Hoots, B L; Charleston, L B; Charleston, J S; Roberts, C R; Markowitz, H

2009-04-01

The manner in which an animal's environment is furnished may have significant implications for animal welfare as well as research outcomes. We evaluated four different housing conditions to determine the effects of what has been considered standard rodent enrichment and the exercise opportunities those environments allow on disease progression in the amyotrophic lateral sclerosis mouse model. Forty-eight copper/zinc superoxide dismutase mice (strain: B6SJL-TgN [SOD1-G931]1Gur) (SOD1) and 48 control (C) (strain: B6SJL-TgN[SOD1]2Gur) male mice were randomly assigned to four different conditions where 12 SOD1 and 12 C animals were allotted to each condition (n = 96). Conditions tested the effects of standard housing, a forced exercise regime, access to a mouse house and opportunity for ad libitum exercise on a running wheel. In addition to the daily all-occurrence behavioural sampling, mice were weighed and tested twice per week on gait and Rotor-Rod performance until the mice reached the age of 150 days (C) or met the criteria for our humane endpoint (SOD1). The SOD1 mice exposed to the forced exercise regime and wheel access did better in average lifespan and Rotor-Rod performance, than SOD1 mice exposed to the standard cage and mouse house conditions. In SOD1 mice, stride length remained longest throughout the progression of the disease in mice exposed to the forced exercise regime compared with other SOD1 conditions. Within the control group, mice in the standard cage and forced exercise regime conditions performed significantly less than the mice with the mouse house and wheels on the Rotor-Rod. Alpha motor neuron counts were highest in mice with wheels and in mice exposed to forced exercise regime in both mouse strains. All SOD1 mice had significantly lower alpha neuron counts than controls (P < 0.05). These data show that different enrichment strategies affect behaviour and disease progression in a transgenic mouse model, and may have implications for the effects of these strategies on experimental outcomes.

Exploration of Molecular Factors Impairing Superoxide Dismutase Isoforms Activity in Human Senile Cataractous Lenses

PubMed Central

Rajkumar, Sankaranarayanan; Vasavada, Abhay R.; Praveen, Mamidipudi R.; Ananthan, Rajendran; Reddy, Geereddy B.; Tripathi, Harsha; Ganatra, Darshini A.; Arora, Anshul I.; Patel, Alpesh R.

2013-01-01

Purpose. To explore different molecular factors impairing the activities of superoxide dismutase (SOD) isoforms in senile cataractous lenses. Methods. Enzyme activity of SOD isoforms, levels of their corresponding cofactors copper (Cu), manganese (Mn), zinc (Zn), and expression of mRNA transcripts and proteins were determined in the lenses of human subjects with and without cataract. DNA from lens epithelium (LE) and peripheral blood was isolated. Polymerase chain reaction–single strand conformation polymorphism (PCR-SSCP) followed by sequencing was carried out to screen somatic mutations. The impact of intronic insertion/deletion (INDEL) variations on the splicing process and on the resultant transcript was evaluated. Genotyping of IVS4+42delG polymorphism of SOD1 gene was done by PCR–restriction fragment length polymorphism (RFLP). Results. A significant decrease in Cu/Zn- and Mn-SOD activity (P < 0.001) and in Cu/Zn-SOD transcript (P < 0.001) and its protein (P < 0.05) were found in cataractous lenses. No significant change in the level of copper (P = 0.36) and an increase in the level of manganese (P = 0.01) and zinc (P = 0.02) were observed in cataractous lenses. A significant positive correlation between the level of Cu/Zn-SOD activity and the levels of Cu (P = 0.003) and Zn (P = 0.005) was found in the cataractous lenses. DNA sequencing revealed three intronic INDEL variations in exon4 of SOD1 gene. Splice-junction analysis showed the potential of IVS4+42delG in creating a new cryptic acceptor site. If it is involved in alternate splicing, it could result in generation of SOD1 mRNA transcripts lacking exon4 region. Transcript analysis revealed the presence of complete SOD1 mRNA transcripts. Genotyping revealed the presence of IVS4+42delG polymorphism in all subjects. Conclusions. The decrease in the activity of SOD1 isoform in cataractous lenses was associated with the decreased level of mRNA transcripts and their protein expression and was not associated with either modulation in the level of enzyme cofactors or with INDEL variations. PMID:23970468

Pre-treatment with Chrysanthemum indicum Linné extract protects pyramidal neurons from transient cerebral ischemia via increasing antioxidants in the gerbil hippocampal CA1 region

PubMed Central

Kim, In Hye; Lee, Tae-Kyeong; Cho, Jeong Hwi; Lee, Jae-Chul; Park, Joon Ha; Ahn, Ji Hyeon; Shin, Bich-Na; Chen, Bai Hui; Tae, Hyun-Jin; Kim, Yang Hee; Kim, Jong-Dai; Kim, Young-Myeong; Won, Moo-Ho; Kang, Il Jun

2017-01-01

Chrysanthemum indicum Linné extract (CIL) is used in herbal medicine in East Asia. In the present study, gerbils were orally pre-treated with CIL, and changes of antioxidant enzymes including superoxide dismutase (SOD) 1 and SOD2, catalase (CAT) and glutathione peroxidase (GPX) in the hippocampal CA1 region following 5 min of transient cerebral ischemia were investigated and the neuroprotective effect of CIL in the ischemic CA1 region was examined. SOD1, SOD2, CAT and GPX immunoreactivities were observed in the pyramidal cells of the CA1 region and their immunoreactivities were gradually decreased following ischemia-reperfusion and barely detectable at 5 days post-ischemia. CIL pre-treatment significantly increased immunoreactivities of SOD1, CAT and GPX, but not SOD2, in the CA1 pyramidal cells of the sham-operated animals. In addition, SOD1, SOD2, CAT and GPX immunoreactivities in the CA1 pyramidal cells were significantly higher compared with the ischemia-operated animals. Furthermore, it was identified that pre-treatment with CIL protected the CA1 pyramidal cells in the CA1 region using neuronal nuclei immunohistochemistry and Fluoro-Jade B histofluorescence staining; the protected CA1 pyramidal cells were 67.5% compared with the sham-operated animals. In conclusion, oral CIL pre-treatment increased endogenous antioxidant enzymes in CA1 pyramidal cells in the gerbil hippocampus and protected the cells from transient cerebral ischemic insult. This finding suggested that CIL is promising for the prevention of ischemia-induced neuronal damage. PMID:28534982

Distinct Functions of CCAAT Enhancer-binding Protein Isoforms in the Regulation of Manganese Superoxide Dismutase during Interleukin-1β Stimulation*

PubMed Central

Qiu, Xiaolei; Aiken, Kimberly J.; Chokas, Ann L.; Beachy, Dawn E.; Nick, Harry S.

2008-01-01

The mitochondrial antioxidant enzyme manganese superoxide dismutase (Mn-SOD) is crucial in maintaining cellular and organismal homeostasis. Mn-SOD expression is tightly regulated in a manner that synchronizes its cytoprotective functions during inflammatory challenges. Induction of Mn-SOD gene expression by the proinflammatory cytokine IL-1β is mediated through a complex intronic enhancer element. To identify and characterize the transcription factors required for Mn-SOD enhancer function, a yeast one-hybrid assay was utilized, and two CCAAT enhancer-binding protein (C/EBP) members, C/EBP β and C/EBP δ, were identified. These two transcription factors responded to IL-1β treatment with distinct expression profiles, different temporal yet inducible interactions with the endogenous Mn-SOD enhancer, and also opposite effects on Mn-SOD transcription. C/EBP β is expressed as three isoforms, LAP* (liver-activating protein), LAP, and LIP (liver-inhibitory protein). Our functional analysis demonstrated that only the full-length C/EBP β/LAP* served as a true activator for Mn-SOD, whereas LAP, LIP, and C/EBP δ functioned as potential repressors. Finally, our systematic mutagenesis of the unique N-terminal 21 amino acids further solidified the importance of LAP* in the induction of Mn-SOD and emphasized the crucial role of this isoform. Our data demonstrating the physiological relevance of the N-terminal peptide also provide a rationale for revisiting the role of LAP* in the regulation of other genes and in pathways such as lipogenesis and development. PMID:18559338

SODa: an Mn/Fe superoxide dismutase prediction and design server.

PubMed

Kwasigroch, Jean Marc; Wintjens, René; Gilis, Dimitri; Rooman, Marianne

2008-06-02

Superoxide dismutases (SODs) are ubiquitous metalloenzymes that play an important role in the defense of aerobic organisms against oxidative stress, by converting reactive oxygen species into nontoxic molecules. We focus here on the SOD family that uses Fe or Mn as cofactor. The SODa webtool http://babylone.ulb.ac.be/soda predicts if a target sequence corresponds to an Fe/Mn SOD. If so, it predicts the metal ion specificity (Fe, Mn or cambialistic) and the oligomerization mode (dimer or tetramer) of the target. In addition, SODa proposes a list of residue substitutions likely to improve the predicted preferences for the metal cofactor and oligomerization mode. The method is based on residue fingerprints, consisting of residues conserved in SOD sequences or typical of SOD subgroups, and of interaction fingerprints, containing residue pairs that are in contact in SOD structures. SODa is shown to outperform and to be more discriminative than traditional techniques based on pairwise sequence alignments. Moreover, the fact that it proposes selected mutations makes it a valuable tool for rational protein design.

Exposure of Mn and FeSODs, but not Cu/ZnSOD, to NO leads to nitrosonium and nitroxyl ions generation which cause enzyme modification and inactivation: an in vitro study.

PubMed

Niketíc, V; Stojanović, S; Nikolić, A; Spasić, M; Michelson, A M

1999-11-01

The effect of NO treatment in vitro on structural and functional alterations of Cu/Zn, Mn, and Fe type of SODs was studied. Significant difference in response to NO of Cu/ZnSOD compared to the Mn and Fe types was demonstrated. Cu/ZnSOD was shown to be stable with respect to NO: even on prolonged exposure, NO produced negligible effect on its structure and activity. In contrast, both Mn and Fe types were found to be NO-sensitive: exposure to NO led to their fast and extensive inactivation, which was accompanied by extensive structural alterations, including (in some of the samples tested) the cleavage of enzyme polypeptide chains, presumably at His residues of the enzyme metal binding sites. The generation of nitrosonium (NO+) and nitroxyl (NO-) ions in NO treated Mn and FeSODs, which produce enzyme modifications and inactivation, was demonstrated. The physiological and biomedical significance of described findings is briefly discussed.

Non-native Soluble Oligomers of Cu/Zn Superoxide Dismutase (SOD1) Contain a Conformational Epitope Linked to Cytotoxicity in Amyotrophic Lateral Sclerosis (ALS)

PubMed Central

2015-01-01

Soluble misfolded Cu/Zn superoxide dismutase (SOD1) is implicated in motor neuron death in amyotrophic lateral sclerosis (ALS); however, the relative toxicities of the various non-native species formed by SOD1 as it misfolds and aggregates are unknown. Here, we demonstrate that early stages of SOD1 aggregation involve the formation of soluble oligomers that contain an epitope specific to disease-relevant misfolded SOD1; this epitope, recognized by the C4F6 antibody, has been proposed as a marker of toxic species. Formation of potentially toxic oligomers is likely to be exacerbated by an oxidizing cellular environment, as evidenced by increased oligomerization propensity and C4F6 reactivity when oxidative modification by glutathione is present at Cys-111. These findings suggest that soluble non-native SOD1 oligomers, rather than native-like dimers or monomers, share structural similarity to pathogenic misfolded species found in ALS patients and therefore represent potential cytotoxic agents and therapeutic targets in ALS. PMID:24660965

Characterization of a hyperthermostable Fe-superoxide dismutase from hot spring.

PubMed

He, Yong-Zhi; Fan, Ke-Qiang; Jia, Cui-Juan; Wang, Zhi-Jun; Pan, Wu-Bin; Huang, Li; Yang, Ke-Qian; Dong, Zhi-Yang

2007-05-01

A new gene encoding a thermostable Fe-superoxide dismutase (tcSOD) was identified from a metagenomic library prepared from a hot spring sample. The open reading frame of tcSOD encoded a 211 amino acid protein. The recombinant protein was overexpressed in Escherichia coli and confirmed to be a Fe-SOD with a specific activity of 1,890 U/mg using the pyrogallol method. The enzyme was highly stable at 80 degrees C and retained 50% activity after heat treatment at 95 degrees C for 2 h. It showed striking stability across a wide pH span from 4 to 11. The native form of the enzyme was determined as a homotetramer by analytical ultracentrifugation and gradient native polyacrylamide gel electrophoresis. Fe(2+) was found to be important to SOD activity and to the stability of tcSOD dimer. Comparative modeling analyses of tcSOD tetramer indicate that its high thermostability is mainly due to the presence of a large number of intersubunit ion pairs and hydrogen bonds and to a decrease in solvent accessible hydrophobic surfaces.

Dietary supplementation with a superoxide dismutase-melon concentrate reduces stress, physical and mental fatigue in healthy people: a randomised, double-blind, placebo-controlled trial.

PubMed

Carillon, Julie; Notin, Claire; Schmitt, Karine; Simoneau, Guy; Lacan, Dominique

2014-06-19

We aimed to investigate effects of superoxide dismutase (SOD)-melon concentrate supplementation on psychological stress, physical and mental fatigue in healthy people. A randomized, double-blind, placebo-controlled trial was performed on 61 people divided in two groups: active supplement (n = 32) and placebo (n = 29) for 12 weeks. Volunteers were given one small hard capsule per day. One capsule contained 10 mg of SOD-melon concentrate (140 U of SOD) and starch for the active supplement and starch only for the placebo. Stress and fatigue were evaluated using four psychometric scales: PSS-14; SF-36; Stroop tests and Prevost scale. The supplementation with SOD-melon concentrate significantly decreased perceived stress, compared to placebo. Moreover, quality of life was improved and physical and mental fatigue were reduced with SOD-melon concentrate supplementation. SOD-melon concentrate supplementation appears to be an effective and natural way to reduce stress and fatigue. trial approved by the ethical committee of Poitiers (France), and the ClinicalTrials.gov Identifier is NCT01767922.

Thermal fluctuations of immature SOD1 lead to separate folding and misfolding pathways

PubMed Central

Sekhar, Ashok; Rumfeldt, Jessica AO; Broom, Helen R; Doyle, Colleen M; Bouvignies, Guillaume; Meiering, Elizabeth M; Kay, Lewis E

2015-01-01

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease involving cytotoxic conformations of Cu, Zn superoxide dismutase (SOD1). A major challenge in understanding ALS disease pathology has been the identification and atomic-level characterization of these conformers. Here, we use a combination of NMR methods to detect four distinct sparsely populated and transiently formed thermally accessible conformers in equilibrium with the native state of immature SOD1 (apoSOD12SH). Structural models of two of these establish that they possess features present in the mature dimeric protein. In contrast, the other two are non-native oligomers in which the native dimer interface and the electrostatic loop mediate the formation of aberrant intermolecular interactions. Our results show that apoSOD12SH has a rugged free energy landscape that codes for distinct kinetic pathways leading to either maturation or non-native association and provide a starting point for a detailed atomic-level understanding of the mechanisms of SOD1 oligomerization. DOI: http://dx.doi.org/10.7554/eLife.07296.001 PMID:26099300

Mitochondrial Superoxide Dismutase and Yap1p Act as a Signaling Module Contributing to Ethanol Tolerance of the Yeast Saccharomyces cerevisiae.

PubMed

Zyrina, Anna N; Smirnova, Ekaterina A; Markova, Olga V; Severin, Fedor F; Knorre, Dmitry A

2017-02-01

There are two superoxide dismutases in the yeast Saccharomyces cerevisiae-cytoplasmic and mitochondrial enzymes. Inactivation of the cytoplasmic enzyme, Sod1p, renders the cells sensitive to a variety of stresses, while inactivation of the mitochondrial isoform, Sod2p, typically has a weaker effect. One exception is ethanol-induced stress. Here we studied the role of Sod2p in ethanol tolerance of yeast. First, we found that repression of SOD2 prevents ethanol-induced relocalization of yeast hydrogen peroxide-sensing transcription factor Yap1p, one of the key stress resistance proteins. In agreement with this, the levels of Trx2p and Gsh1p, proteins encoded by Yap1 target genes, were decreased in the absence of Sod2p. Analysis of the ethanol sensitivities of the cells lacking Sod2p, Yap1p, or both indicated that the two proteins act in the same pathway. Moreover, preconditioning with hydrogen peroxide restored the ethanol resistance of yeast cells with repressed SOD2 Interestingly, we found that mitochondrion-to-nucleus signaling by Rtg proteins antagonizes Yap1p activation. Together, our data suggest that hydrogen peroxide produced by Sod2p activates Yap1p and thus plays a signaling role in ethanol tolerance. Baker's yeast harbors multiple systems that ensure tolerance to high concentrations of ethanol. Still, the role of mitochondria under severe ethanol stress in yeast is not completely clear. Our study revealed a signaling function of mitochondria which contributes significantly to the ethanol tolerance of yeast cells. We found that mitochondrial superoxide dismutase Sod2p and cytoplasmic hydrogen peroxide sensor Yap1p act together as a module of the mitochondrion-to-nucleus signaling pathway. We also report cross talk between this pathway and the conventional retrograde signaling cascade activated by dysfunctional mitochondria. Copyright © 2017 American Society for Microbiology.

Overexpression of antioxidant enzymes in diaphragm muscle does not alter contraction-induced fatigue or recovery

PubMed Central

McClung, Joseph M.; DeRuisseau, Keith C.; Whidden, Melissa A.; Van Remmen, Holly; Richardson, Arlan; Song, Wook; Vrabas, Ioannis S.; Powers, Scott K.

2010-01-01

Low levels of reactive oxygen species (ROS) production are necessary to optimize muscle force production in unfatigued muscle. In contrast, sustained high levels of ROS production have been linked to impaired muscle force production and contraction-induced skeletal muscle fatigue. Using genetically engineered mice, we tested the hypothesis that the independent transgenic overexpression of catalase (CAT), copper/zinc superoxide dismutase (CuZnSOD; SOD1) or manganese superoxide dismutase (MnSOD; SOD2) antioxidant enzymes would negatively affect force production in unfatigued diaphragm muscle but would delay the development of muscle fatigue and enhance force recovery after fatiguing contractions. Diaphragm muscle from wild-type littermates (WT) and from CAT, SOD1 and SOD2 overexpressing mice were subjected to an in vitro contractile protocol to investigate the force–frequency characteristics, the fatigue properties and the time course of recovery from fatigue. The CAT, SOD1 and SOD2 overexpressors produced less specific force (in N cm−2) at stimulation frequencies of 20–300 Hz and produced lower maximal tetanic force than WT littermates. The relative development of muscle fatigue and recovery from fatigue were not influenced by transgenic overexpression of any antioxidant enzyme. Morphologically, the mean cross-sectional area (in μm2) of diaphragm myofibres expressing myosin heavy chain type IIA was decreased in both CAT and SOD2 transgenic animals, and the percentage of non-contractile tissue increased in diaphragms from all transgenic mice. In conclusion, our results do not support the hypothesis that overexpression of independent antioxidant enzymes protects diaphragm muscle from contraction-induced fatigue or improves recovery from fatigue. Moreover, our data are consistent with the concept that a basal level of ROS is important to optimize muscle force production, since transgenic overexpression of major cellular antioxidants is associated with contractile dysfunction. Finally, the transgenic overexpression of independent endogenous antioxidants alters diaphragm skeletal muscle morphology, and these changes may also contribute to the diminished specific force production observed in these animals. PMID:19783618

A Phase I, Randomised, First-in-Human Study of an Antisense Oligonucleotide Directed Against SOD1 Delivered Intrathecally in SOD1-Familial ALS Patients

PubMed Central

Miller, Timothy; Pestronk, Alan; David, William; Rothstein, Jeffrey; Simpson, Ericka; Appel, Stanley H.; Andres, Patricia L.; Mahoney, Katy; Allred, Peggy; Alexander, Katie; Ostrow, Lyle W.; Schoenfeld, David; Macklin, Eric A.; Norris, Daniel A.; Manousakis, Georgios; Crisp, Matthew; Smith, Richard; Bennett, C.F.; Bishop, Kathie; Cudkowicz, Merit E

2013-01-01

Objective To evaluate the safety, tolerability, and pharmacokinetics of an antisense oligonucleotide designed to inhibit SOD1 expression (ISIS 333611) following intrathecal administration in patients with SOD1-related familial amyotrophic lateral sclerosis (ALS). Background Mutations in SOD1 cause 13% of familial ALS. In animal studies, ISIS 333611 delivered to the cerebrospinal fluid (CSF) distributed to the brain and spinal cord, decreased SOD1 mRNA and protein levels in spinal cord tissue, and prolonged survival in the SOD1G93A rat ALS model. Methods In a randomized, placebo controlled Phase 1 trial, ISIS 333611 was delivered by intrathecal infusion using an external pump over 11.5 hours at increasing doses to four cohorts of eight SOD1 positive ALS subjects (randomized 6 drug: 2 placebo/cohort). Subjects were allowed to re-enroll in subsequent cohorts. Safety and tolerability assessments were made during the infusion and periodically over 28 days following the infusion. CSF and plasma drug levels were measured. Findings No dose-limiting toxicities were identified at doses up to 3.0 mg. No safety or tolerability concerns related to ISIS 333611 were identified. There were no serious adverse events (AEs) in ISIS 333611-treated subjects. Re-enrollment and re-dosing of subjects with ISIS 333611 was also well tolerated. Dose-dependent CSF and plasma concentrations were observed. Interpretation In this first clinical study to report intrathecal delivery of an antisense oligonucleotide, ISIS 333611 was well tolerated when administered as an intrathecal infusion in subjects with SOD1 familial ALS. CSF and plasma drug levels were consistent with levels predicted from preclinical studies. These results suggest that antisense oligonucleotide delivery to the central nervous system may be a feasible therapeutic strategy for neurological disorders. Source of funding ALS Association, Muscular Dystrophy Association, Isis Pharmaceuticals PMID:23541756

Mitochondrial Superoxide Dismutase and Yap1p Act as a Signaling Module Contributing to Ethanol Tolerance of the Yeast Saccharomyces cerevisiae

PubMed Central

Zyrina, Anna N.; Smirnova, Ekaterina A.; Markova, Olga V.; Severin, Fedor F.

2016-01-01

ABSTRACT There are two superoxide dismutases in the yeast Saccharomyces cerevisiae—cytoplasmic and mitochondrial enzymes. Inactivation of the cytoplasmic enzyme, Sod1p, renders the cells sensitive to a variety of stresses, while inactivation of the mitochondrial isoform, Sod2p, typically has a weaker effect. One exception is ethanol-induced stress. Here we studied the role of Sod2p in ethanol tolerance of yeast. First, we found that repression of SOD2 prevents ethanol-induced relocalization of yeast hydrogen peroxide-sensing transcription factor Yap1p, one of the key stress resistance proteins. In agreement with this, the levels of Trx2p and Gsh1p, proteins encoded by Yap1 target genes, were decreased in the absence of Sod2p. Analysis of the ethanol sensitivities of the cells lacking Sod2p, Yap1p, or both indicated that the two proteins act in the same pathway. Moreover, preconditioning with hydrogen peroxide restored the ethanol resistance of yeast cells with repressed SOD2. Interestingly, we found that mitochondrion-to-nucleus signaling by Rtg proteins antagonizes Yap1p activation. Together, our data suggest that hydrogen peroxide produced by Sod2p activates Yap1p and thus plays a signaling role in ethanol tolerance. IMPORTANCE Baker's yeast harbors multiple systems that ensure tolerance to high concentrations of ethanol. Still, the role of mitochondria under severe ethanol stress in yeast is not completely clear. Our study revealed a signaling function of mitochondria which contributes significantly to the ethanol tolerance of yeast cells. We found that mitochondrial superoxide dismutase Sod2p and cytoplasmic hydrogen peroxide sensor Yap1p act together as a module of the mitochondrion-to-nucleus signaling pathway. We also report cross talk between this pathway and the conventional retrograde signaling cascade activated by dysfunctional mitochondria. PMID:27864171

Exosomes from NSC-34 Cells Transfected with hSOD1-G93A Are Enriched in miR-124 and Drive Alterations in Microglia Phenotype.

PubMed

Pinto, Sara; Cunha, Carolina; Barbosa, Marta; Vaz, Ana R; Brites, Dora

2017-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disorder affecting motor neurons (MNs). Evidences indicate that ALS is a non-cell autonomous disease in which glial cells participate in both disease onset and progression. Exosomal transfer of mutant copper-zinc superoxide dismutase 1 (mSOD1) from cell-to-cell was suggested to contribute to disease dissemination. Data from our group and others showed that exosomes from activated cells contain inflammatory-related microRNAs (inflamma-miRNAs) that recapitulate the donor cell. While glia-derived exosomes and their effects in neurons have been addressed by several studies, only a few investigated the influence of motor neuron (MN)-derived exosomes in other cell function, the aim of the present study. We assessed a set of inflamma-miRs in NSC-34 MN-like cells transfected with mutant SOD1(G93A) and extended the study into their derived exosomes (mSOD1 exosomes). Then, the effects produced by mSOD1 exosomes in the activation and polarization of the recipient N9 microglial cells were investigated. Exosomes in coculture with N9 microglia and NSC-34 cells [either transfected with either wild-type (wt) human SOD1 or mutant SOD1(G93A)] showed to be transferred into N9 cells. Increased miR-124 expression was found in mSOD1 NSC-34 cells and in their derived exosomes. Incubation of mSOD1 exosomes with N9 cells determined a sustained 50% reduction in the cell phagocytic ability. It also caused a persistent NF-kB activation and an acute generation of NO, MMP-2, and MMP-9 activation, as well as upregulation of IL-1β, TNF-α, MHC-II, and iNOS gene expression, suggestive of induced M1 polarization. Marked elevation of IL-10, Arginase 1, TREM2, RAGE, and TLR4 mRNA levels, together with increased miR-124, miR-146a, and miR-155, at 24 h incubation, suggest the switch to mixed M1 and M2 subpopulations in the exosome-treated N9 microglial cells. Exosomes from mSOD1 NSC-34 MNs also enhanced the number of senescent-like positive N9 cells. Data suggest that miR-124 is translocated from the mSOD1 MNs to exosomes, which determine early and late phenotypic alterations in the recipient N9-microglial cells. In conclusion, modulation of the inflammatory-associated miR-124, in mSOD1 NSC-34 MNs, with potential benefits in the cargo of their exosomes may reveal a promising therapeutic strategy in halting microglia activation and associated effects in MN degeneration.

Transcriptomic indices of fast and slow disease progression in two mouse models of amyotrophic lateral sclerosis.

PubMed

Nardo, Giovanni; Iennaco, Raffaele; Fusi, Nicolò; Heath, Paul R; Marino, Marianna; Trolese, Maria C; Ferraiuolo, Laura; Lawrence, Neil; Shaw, Pamela J; Bendotti, Caterina

2013-11-01

Amyotrophic lateral sclerosis is heterogeneous with high variability in the speed of progression even in cases with a defined genetic cause such as superoxide dismutase 1 (SOD1) mutations. We reported that SOD1(G93A) mice on distinct genetic backgrounds (C57 and 129Sv) show consistent phenotypic differences in speed of disease progression and life-span that are not explained by differences in human SOD1 transgene copy number or the burden of mutant SOD1 protein within the nervous system. We aimed to compare the gene expression profiles of motor neurons from these two SOD1(G93A) mouse strains to discover the molecular mechanisms contributing to the distinct phenotypes and to identify factors underlying fast and slow disease progression. Lumbar spinal motor neurons from the two SOD1(G93A) mouse strains were isolated by laser capture microdissection and transcriptome analysis was conducted at four stages of disease. We identified marked differences in the motor neuron transcriptome between the two mice strains at disease onset, with a dramatic reduction of gene expression in the rapidly progressive (129Sv-SOD1(G93A)) compared with the slowly progressing mutant SOD1 mice (C57-SOD1(G93A)) (1276 versus 346; Q-value ≤ 0.01). Gene ontology pathway analysis of the transcriptional profile from 129Sv-SOD1(G93A) mice showed marked downregulation of specific pathways involved in mitochondrial function, as well as predicted deficiencies in protein degradation and axonal transport mechanisms. In contrast, the transcriptional profile from C57-SOD1(G93A) mice with the more benign disease course, revealed strong gene enrichment relating to immune system processes compared with 129Sv-SOD1(G93A) mice. Motor neurons from the more benign mutant strain demonstrated striking complement activation, over-expressing genes normally involved in immune cell function. We validated through immunohistochemistry increased expression of the C3 complement subunit and major histocompatibility complex I within motor neurons. In addition, we demonstrated that motor neurons from the slowly progressing mice activate a series of genes with neuroprotective properties such as angiogenin and the nuclear factor (erythroid-derived 2)-like 2 transcriptional regulator. In contrast, the faster progressing mice show dramatically reduced expression at disease onset of cell pathways involved in neuroprotection. This study highlights a set of key gene and molecular pathway indices of fast or slow disease progression which may prove useful in identifying potential disease modifiers responsible for the heterogeneity of human amyotrophic lateral sclerosis and which may represent valid therapeutic targets for ameliorating the disease course in humans.

Protective effect of human recombinant copper-zinc superoxide dismutase on zone of stasis survival in burns in rats.

PubMed

Shalom, Avshalom; Kramer, Eyal; Westreich, Melvyn

2011-06-01

Superoxide dismutase, acting as a scavenger of oxygen free radicals, has shown mixed results in increasing burn wound survival. Originally, we demonstrated that human recombinant copper-zinc superoxide dismutase (Hr-CuZnSOD) could increase the survival of failing ischemic flaps in a rat model. Because of the possible similar pathophysiology of tissue ischemia in flaps and the zone of stasis in burns, we conducted a later study using 2 groups of rats with standardized intermediate burns, to ascertain whether Hr-CuZnSOD could increase zone of stasis survival in rats. The results showed that postburn Hr-CuZnSOD failed to improve zone of stasis survival in burns. We decided to undertake a new controlled study to ascertain whether there is a protective effect of Hr-CuZnSOD in cases of intermediate burns. We used 2 groups of rats, one of which received prophylactic treatments with Hr-CuZnSOD before the induction of standardized intermediate burns. Results showed that preburn Hr-CuZnSOD also failed to improve zone of stasis survival in burns. Further studies are needed to adequately understand the effect of oxygen free radicals in burn wound pathophysiology and to determine whether Hr-CuZnSOD has a role in the clinical management of burns or should be abandoned.

Sod1 deficiency reduces incubation time in mouse models of prion disease.

PubMed

Akhtar, Shaheen; Grizenkova, Julia; Wenborn, Adam; Hummerich, Holger; Fernandez de Marco, Mar; Brandner, Sebastian; Collinge, John; Lloyd, Sarah E

2013-01-01

Prion infections, causing neurodegenerative conditions such as Creutzfeldt-Jakob disease and kuru in humans, scrapie in sheep and BSE in cattle are characterised by prolonged and variable incubation periods that are faithfully reproduced in mouse models. Incubation time is partly determined by genetic factors including polymorphisms in the prion protein gene. Quantitative trait loci studies in mice and human genome-wide association studies have confirmed that multiple genes are involved. Candidate gene approaches have also been used and identified App, Il1-r1 and Sod1 as affecting incubation times. In this study we looked for an association between App, Il1-r1 and Sod1 representative SNPs and prion disease incubation time in the Northport heterogeneous stock of mice inoculated with the Chandler/RML prion strain. No association was seen with App, however, significant associations were seen with Il1-r1 (P = 0.02) and Sod1 (P<0.0001) suggesting that polymorphisms at these loci contribute to the natural variation observed in incubation time. Furthermore, following challenge with Chandler/RML, ME7 and MRC2 prion strains, Sod1 deficient mice showed highly significant reductions in incubation time of 20, 13 and 24%, respectively. No differences were detected in Sod1 expression or activity. Our data confirm the protective role of endogenous Sod1 in prion disease.

Subunit Dissociation and Metal Binding by Escherichia coli apo-Manganese Superoxide Dismutase

PubMed Central

Whittaker, Mei M.; Lerch, Thomas F.; Kirillova, Olga; Chapman, Michael S.; Whittaker, James W.

2010-01-01

Metal binding by apo-manganese superoxide dismutase (apo-MnSOD) is essential for functional maturation of the enzyme. Previous studies have demonstrated that metal binding by apo-MnSOD is conformationally gated, requiring protein reorganization for the metal to bind. We have now solved the X-ray crystal structure of apo-MnSOD at 1.9 Å resolution. The organization of active site residues is independent of the presence of the metal cofactor, demonstrating that protein itself templates the unusual metal coordination geometry. Electrophoretic analysis of mixtures of apo- and (Mn2)-MnSOD, dye-conjugated protein, or C-terminal Strep-tag II fusion protein reveals a dynamic subunit exchange process associated with cooperative metal binding by the two subunits of the dimeric protein. In contrast, (S126C) (SS) apo-MnSOD, which contains an inter-subunit covalent disulfide crosslink, exhibits anticooperative metal binding. The protein concentration dependence of metal uptake kinetics implies that protein dissociation is involved in metal binding by the wild type apo-protein, although other processes may also contribute to gating metal uptake. Protein concentration dependent small-zone size exclusion chromatography is consistent with apo-MnSOD dimer dissociation at low protein concentration (KD = 1×10−6 M). Studies on metal uptake by apo-MnSOD in Escherichia coli cells show that the protein exhibits similar behavior in vivo and in vitro. PMID:21044611

A High-Throughput Screening Method for Small-Molecule Inhibitors of the Aberrant Mutant SOD1 and Dynein Complex Interaction

PubMed Central

Tang, Xiaohu; Seyb, Kathleen I.; Huang, Mickey; Schuman, Eli R.; Shi, Ping; Zhu, Haining; Glicksman, Marcie A.

2013-01-01

Aberrant protein-protein interactions are attractive drug targets in a variety of neurodegenerative diseases due to the common pathology of accumulation of protein aggregates. In amyotrophic lateral sclerosis, mutations in SOD1 cause the formation of aggregates and inclusions that may sequester other proteins and disrupt cellular processes. It has been demonstrated that mutant SOD1, but not wild-type SOD1, interacts with the axonal transport motor dynein and that this interaction contributes to motor neuron cell death, suggesting that disrupting this interaction may be a potential therapeutic target. However, it can be challenging to configure a high-throughput screening (HTS)–compatible assay to detect inhibitors of a protein-protein interaction. Here we describe the development and challenges of an HTS for small-molecule inhibitors of the mutant SOD1-dynein interaction. We demonstrate that the interaction can be formed by coexpressing the A4V mutant SOD1 and dynein intermediate complex in cells and that this interaction can be disrupted by compounds added to the cell lysates. Finally, we show that some of the compounds identified from a pilot screen to inhibit the protein-protein interaction with this method specifically disrupt the interaction between the dynein complex and mtSOD1 but not the dynein complex itself when applied to live cells. PMID:22140121

Superoxide dismutases and glutaredoxins have a distinct role in the response of Candida albicans to oxidative stress generated by the chemical compounds menadione and diamide.

PubMed

Chaves, Guilherme Maranhão; da Silva, Walicyranison Plinio

2012-12-01

To cope with oxidative stress, Candida albicans possesses several enzymes involved in a number of biological processes, including superoxide dismutases (Sods) and glutaredoxins (Grxs). The resistance of C. albicans to reactive oxygen species is thought to act as a virulence factor. Genes such as SOD1 and GRX2, which encode for a Sod and Grx, respectively, in C. albicans are widely recognised to be important for pathogenesis. We generated a double mutant, Δgrx2/sod1, for both genes. This strain is very defective in hyphae formation and is susceptible to killing by neutrophils. When exposed to two compounds that generate reactive oxygen species, the double null mutant was susceptible to menadione and resistant to diamide. The reintegration of the SOD1 gene in the null mutant led to recovery in resistance to menadione, whereas reintegration of the GRX2 gene made the null mutant sensitive to diamide. Despite having two different roles in the responses to oxidative stress generated by chemical compounds, GRX2 and SOD1 are important for C. albicans pathogenesis because the double mutant Δgrx2/sod1 was very susceptible to neutrophil killing and was defective in hyphae formation in addition to having a lower virulence in an animal model of systemic infection.

Distinct oxidative cleavage and modification of bovine [Cu-Zn]-SOD by an ascorbic acid/Cu(II) system: Identification of novel copper binding site on SOD molecule

PubMed Central

Uehara, Hiroshi; Luo, Shen; Aryal, Baikuntha; Levine, Rodney L.; Rao, V. Ashutosh

2016-01-01

We investigated the combined effect of ascorbate and copper [Asc/Cu(II)] on the integrity of bovine [Cu-Zn]-superoxide dismutase (bSOD1) as a model system to study the metal catalyzed oxidation (MCO) and fragmentation of proteins. We found Asc/Cu(II) mediates specific cleavage of bSOD1 and generates 12.5 and 3.2 kDa fragments in addition to oxidation/carbonylation of the protein. The effect of other tested transition metals, a metal chelator, and hydrogen peroxide on the cleavage and oxidation indicated that binding of copper to a previously unknown site on SOD1 is responsible for the Asc/Cu(II) specific cleavage and oxidation. We utilized tandem mass spectrometry to identify the specific cleavage sites of Asc/Cu(II)-treated bSOD1. Analyses of tryptic- and AspN-peptides have demonstrated the cleavage to occur at Gly31 with peptide bond breakage with Thr30 and Ser32 through diamide and α-amidation pathways, respectively. The three-dimensional structure of bSOD1 reveals the imidazole ring of His19 localized within 5 Angstrom from the α-carbon of Gly31 providing a structural basis that copper ion, most likely coordinated by His19, catalyzes the specific cleavage reaction. PMID:26872685

Distinct oxidative cleavage and modification of bovine [Cu- Zn]-SOD by an ascorbic acid/Cu(II) system: Identification of novel copper binding site on SOD molecule.

PubMed

Uehara, Hiroshi; Luo, Shen; Aryal, Baikuntha; Levine, Rodney L; Rao, V Ashutosh

2016-05-01

We investigated the combined effect of ascorbate and copper [Asc/Cu(II)] on the integrity of bovine [Cu-Zn]-superoxide dismutase (bSOD1) as a model system to study the metal catalyzed oxidation (MCO) and fragmentation of proteins. We found Asc/Cu(II) mediates specific cleavage of bSOD1 and generates 12.5 and 3.2kDa fragments in addition to oxidation/carbonylation of the protein. The effect of other tested transition metals, a metal chelator, and hydrogen peroxide on the cleavage and oxidation indicated that binding of copper to a previously unknown site on SOD1 is responsible for the Asc/Cu(II) specific cleavage and oxidation. We utilized tandem mass spectrometry to identify the specific cleavage sites of Asc/Cu(II)-treated bSOD1. Analyses of tryptic- and AspN-peptides have demonstrated the cleavage to occur at Gly31 with peptide bond breakage with Thr30 and Ser32 through diamide and α-amidation pathways, respectively. The three-dimensional structure of bSOD1 reveals the imidazole ring of His19 localized within 5Å from the α-carbon of Gly31 providing a structural basis that copper ion, most likely coordinated by His19, catalyzes the specific cleavage reaction. Published by Elsevier Inc.

Hematopoietic Stem Cell Regeneration Enhanced by Ectopic Expression of ROS-detoxifying Enzymes in Transplant Mice

PubMed Central

Miao, Weimin; XuFeng, Richard; Park, Moo-Rim; Gu, Haihui; Hu, Linping; Kang, Jin Wook; Ma, Shihui; Liang, Paulina H; Li, Yanxin; Cheng, Haizi; Yu, Hui; Epperly, Michael; Greenberger, Joel; Cheng, Tao

2013-01-01

High levels of reactive oxygen species (ROS) can exhaust hematopoietic stem cells (HSCs). Thus, maintaining a low state of redox in HSCs by modulating ROS-detoxifying enzymes may augment the regeneration potential of HSCs. Our results show that basal expression of manganese superoxide dismutase (MnSOD) and catalase were at low levels in long-term and short-term repopulating HSCs, and administration of a MnSOD plasmid and lipofectin complex (MnSOD-PL) conferred radiation protection on irradiated recipient mice. To assess the intrinsic role of elevated MnSOD or catalase in HSCs and hematopoietic progenitor cells, the MnSOD or catalase gene was overexpressed in mouse hematopoietic cells via retroviral transduction. The impact of MnSOD and catalase on hematopoietic progenitor cells was mild, as measured by colony-forming units (CFUs). However, overexpressed catalase had a significant beneficial effect on long-term engraftment of transplanted HSCs, and this effect was further enhanced after an insult of low-dose γ-irradiation in the transplant mice. In contrast, overexpressed MnSOD exhibited an insignificant effect on long-term engraftment of transplanted HSCs, but had a significant beneficial effect after an insult of sublethal irradiation. Taken together, these results demonstrate that HSC function can be enhanced by ectopic expression of ROS-detoxifying enzymes, especially after radiation exposure in vivo. PMID:23295952

Effect of hypoxia mimetic cobalt chloride on the expression of extracellular-superoxide dismutase in retinal pericytes.

PubMed

Adachi, Tetsuo; Aida, Kazunari; Nishihara, Hiroko; Kamiya, Tetsuro; Hara, Hirokazu

2011-01-01

The initial clinical stage of diabetic retinopathy (DR) is characterized by the development of intraretinal microvascular abnormalities. The increased formation of reactive oxygen species (ROS) is thought to be a key event in the pathogenesis of DR. Extracellular-superoxide dismutase (EC-SOD) is an anti-inflammatory enzyme that is distributed mainly in vascular cells and protects cells from ROS by scavenging superoxide anion. Treatment with cobalt chloride (CoCl(2)) decreased the expression of EC-SOD but not other SOD isozymes in pericytes accompanied with an increase of intracellular ROS production. Pre-treatment with N-acetylcysteine (NAC) significantly suppressed the ROS production and down-regulation of EC-SOD. We observed the activation of caspase-3 and DNA fragmentation as signs of apoptotic process by CoCl(2) treatment. In addition, these phenomena were significantly inhibited by pre-treatment with NAC. EC-SOD enhancer 4-phenyl butyric acid also suppressed the caspase-3 activation. It is known that the presence of a high level of EC-SOD throughout the vessel walls might have an important protective role against superoxide in the vascular system. The decrease in EC-SOD expression accompanied with elevation of ROS level in pericytes under hypoxia might induce and/or promote the ROS-triggered apoptosis of pericytes and the development of pathogenesis in DR.

Evaluation of recombinant protein superoxide dismutase of Haemophilus parasuis strain SH0165 as vaccine candidate in a mouse model.

PubMed

Guo, Ling; Xu, Lei; Wu, Tao; Fu, Shulin; Qiu, Yinsheng; Hu, Chien-An Andy; Ren, Xinglong; Liu, Rongrong; Ye, Mengdie

2017-04-01

Haemophilus parasuis can cause a severe membrane inflammation disorder. It has been documented that superoxide dismutase (SOD) is a potential target to treat systemic inflammatory diseases. Therefore, we constructed an experimental H. parasuis subunit vaccine SOD and determined the protective efficacy of SOD using a lethal dose challenge against H. parasuis serovar 4 strain MD0322 and serovar 5 strain SH0165 in a mouse model. The results demonstrated that SOD could induce a strong humoral immune response in mice and provide significant immunoprotection efficacy against a lethal dose of H. parasuis serovar 4 strain MD0322 or serovar 5 strain SH0165 challenge. IgG subtype analysis indicated SOD protein could trigger a bias toward a Th1-type immune response and induce the proliferation of splenocytes and secretion of IL-2 and IFN-γ of splenocytes. In addition, serum in mice from the SOD-immunized group could inhibit the growth of strain MD0322 and strain SH0165 in the whole-blood killing bacteria assay. This is the first report that immunization of mice with SOD protein could provide protective effect against a lethal dose of H. parasuis serovar 4 and serovar 5 challenge in mice, which may provide a novel approach against heterogeneous serovar infection of H. parasuis in future.

SOD1 Overexpression Preserves Baroreflex Control of Heart Rate with an Increase of Aortic Depressor Nerve Function

PubMed Central

Hatcher, Jeffrey; Gu, He; Cheng, Zixi (Jack)

2016-01-01

Overproduction of reactive oxygen species (ROS), such as the superoxide radical (O2 ∙−), is associated with diseases which compromise cardiac autonomic function. Overexpression of SOD1 may offer protection against ROS damage to the cardiac autonomic nervous system, but reductions of O2 ∙− may interfere with normal cellular functions. We have selected the C57B6SJL-Tg (SOD1)2 Gur/J mouse as a model to determine whether SOD1 overexpression alters cardiac autonomic function, as measured by baroreflex sensitivity (BRS) and aortic depressor nerve (ADN) recordings, as well as evaluation of baseline heart rate (HR) and mean arterial pressure (MAP). Under isoflurane anesthesia, C57 wild-type and SOD1 mice were catheterized with an arterial pressure transducer and measurements of HR and MAP were taken. After establishing a baseline, hypotension and hypertension were induced by injection of sodium nitroprusside (SNP) and phenylephrine (PE), respectively, and ΔHR versus ΔMAP were recorded as a measure of baroreflex sensitivity (BRS). SNP and PE treatment were administered sequentially after a recovery period to measure arterial baroreceptor activation by recording aortic depressor nerve activity. Our findings show that overexpression of SOD1 in C57B6SJL-Tg (SOD1)2 Gur/J mouse preserved the normal HR, MAP, and BRS but enhanced aortic depressor nerve function. PMID:26823951

General method for site-directed mutagenesis in Escherichia coli O18ac:K1:H7: deletion of the inducible superoxide dismutase gene, sodA, does not diminish bacteremia in neonatal rats.

PubMed

Bloch, C A; Thorne, G M; Ausubel, F M

1989-07-01

A defined deletion in the Escherichia coli K-12 sodA gene (encoding manganese-superoxide dismutase) linked to a nontransposable selectable marker was generated by transposon Tn5 insertion in combination with in vitro mutagenesis. This mutant allele was used to replace the wild-type sodA gene in an E. coli clinical isolate of serotype O18ac:K1:H7 by bacteriophage P1 transduction. The O18ac:K1:H7 sodA mutant contained no manganese-superoxide dismutase and no hybrid manganese-iron-superoxide dismutase. The sodA mutant was more sensitive to paraquat toxicity than were the parental strain and an isogenic mutant bearing an analogously constructed sodA+ Tn5 insertion allele. In a suckling rat model for bacteremia following oral inoculation of E. coli K1, the sodA mutant was undiminished in its capabilities both to colonize the gastrointestinal tract and, surprisingly, to cause bacteremia. In conjunction with the rat model for E. coli K1 pathogenesis, the method for site-directed mutagenesis described in this paper permits determination of the role played in colonization and bacteremia by any K1 gene which either has a homolog in E. coli K-12 or can be cloned and manipulated therein.

Gelam honey protects against gamma-irradiation damage to antioxidant enzymes in human diploid fibroblasts.

PubMed

Ahmad, Tengku Ahbrizal Farizal Tengku; Jubri, Zakiah; Rajab, Nor Fadilah; Rahim, Khairuddin Abdul; Yusof, Yasmin Anum Mohd; Makpol, Suzana

2013-02-11

The present study was designed to determine the radioprotective effects of Malaysian Gelam honey on gene expression and enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of human diploid fibroblasts (HDFs) subjected to gamma-irradiation. Six groups of HDFs were studied: untreated control, irradiated HDFs, Gelam honey-treated HDFs and HDF treated with Gelam honey pre-, during- and post-irradiation. HDFs were treated with 6 mg/mL of sterilized Gelam honey (w/v) for 24 h and exposed to 1 Gray (Gy) of gamma rays at the dose rate of 0.25 Gy/min. Gamma-irradiation was shown to down-regulate SOD1, SOD2, CAT and GPx1 gene expressions (p < 0.05). Conversely, HDFs treated with Gelam honey alone showed up-regulation of all genes studied. Similarly, SOD, CAT and GPx enzyme activities in HDFs decreased with gamma-irradiation and increased when cells were treated with Gelam honey (p < 0.05). Furthermore, of the three different stages of study treatment, pre-treatment with Gelam honey caused up-regulation of SOD1, SOD2 and CAT genes expression and increased the activity of SOD and CAT. As a conclusion, Gelam honey modulates the expression of antioxidant enzymes at gene and protein levels in irradiated HDFs indicating its potential as a radioprotectant agent.

Sodium selenite ameliorates both intestinal and extra-intestinal changes in acetic acid-induced colitis in rats.

PubMed

Soliman, Samar M; Wadie, Walaa; Shouman, Samia A; Ainshoka, Afaf A

2018-06-01

Selenium and its derivatives including sodium selenite (sod sel) belong to the group of essential trace elements needed for proper health and nutrition. They are fairly safe and possess antioxidant and anti-inflammatory properties. The aim of present investigation was to elucidate the effect of sod sel on experimental colitis model in rats. Colitis was induced by intrarectal instillation of 4% (v/v) acetic acid. Two hours later, sod sel was given to rats on a daily basis for 15 consecutive days. Clinical symptoms, colon mass index, spleen weight inflammatory markers, hematological, biochemical, macroscopic, and histological changes were determined. Sod sel markedly ameliorated colitis as evidenced by a significant decrease in macroscopic and microscopic score, disease activity index, colon mass index, and spleen weight. Treatment with sod sel attenuated oxidative stress in the colon by normalizing the colonic content of nitric oxide, malondialdehyde, and reduced glutathione, as well as the activities of catalase, superoxide dismutase, and junctional adhesion molecule (JAM-a). In addition, it significantly reduced colonic myeloperoxidase content, the intercellular adhesion molecule (ICAM-1), and the proinflammatory cytokines; TNF-α, IL-1β. Moreover, sod sel normalized hematological parameters, serum transaminases, and kidney and liver function enzymes. The current study indicates that sod sel was effective in ameliorating the intestinal and extra-intestinal manifestation in acetic acid-induced colitis through its antioxidant, anti-inflammatory, and immunomodulatory effects.

Oxidized Low-Density Lipoprotein-Activated c-Jun NH2-Terminal Kinase Regulates Manganese Superoxide Dismutase Ubiquitination

PubMed Central

Takabe, Wakako; Li, Rongsong; Ai, Lisong; Yu, Fei; Berliner, Judith A.; Hsiai, Tzung K.

2012-01-01

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. Methods and 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. Conclusion OxLDL-induced JNK activation regulates mitochondrial redox status and Mn-SOD protein degradation via JNK-dependent ubiquitination, leading to endothelial cell apoptosis. PMID:20139358

Interacting disturbances: Wildfire severity affected by stage of forest disease invasion

Treesearch

Margaret Metz; Kerri Frangioso; Ross Meentemeyer; David Rizzo

2010-01-01

Sudden oak death (SOD) is an emerging forest disease causing extensive tree mortality in coastal California forests. Recent California wildfires provided an opportunity to test a major assumption underlying discussions of SOD and land management: SOD mortality will increase fire severity. We examined pre-fire fuels from host species in a forest monitoring plot network...

Mitochondrial and Cytoplasmic ROS Have Opposing Effects on Lifespan

PubMed Central

Schaar, Claire E.; Dues, Dylan J.; Spielbauer, Katie K.; Machiela, Emily; Cooper, Jason F.; Senchuk, Megan; Hekimi, Siegfried; Van Raamsdonk, Jeremy M.

2015-01-01

Reactive oxygen species (ROS) are highly reactive, oxygen-containing molecules that can cause molecular damage within the cell. While the accumulation of ROS-mediated damage is widely believed to be one of the main causes of aging, ROS also act in signaling pathways. Recent work has demonstrated that increasing levels of superoxide, one form of ROS, through treatment with paraquat, results in increased lifespan. Interestingly, treatment with paraquat robustly increases the already long lifespan of the clk-1 mitochondrial mutant, but not other long-lived mitochondrial mutants such as isp-1 or nuo-6. To genetically dissect the subcellular compartment in which elevated ROS act to increase lifespan, we deleted individual superoxide dismutase (sod) genes in clk-1 mutants, which are sensitized to ROS. We find that only deletion of the primary mitochondrial sod gene, sod-2 results in increased lifespan in clk-1 worms. In contrast, deletion of either of the two cytoplasmic sod genes, sod-1 or sod-5, significantly decreases the lifespan of clk-1 worms. Further, we show that increasing mitochondrial superoxide levels through deletion of sod-2 or treatment with paraquat can still increase lifespan in clk-1;sod-1 double mutants, which live shorter than clk-1 worms. The fact that mitochondrial superoxide can increase lifespan in worms with a detrimental level of cytoplasmic superoxide demonstrates that ROS have a compartment specific effect on lifespan – elevated ROS in the mitochondria acts to increase lifespan, while elevated ROS in the cytoplasm decreases lifespan. This work also suggests that both ROS-dependent and ROS-independent mechanisms contribute to the longevity of clk-1 worms. PMID:25671321

CuZnSOD gene deletion targeted to skeletal muscle leads to loss of contractile force but does not cause muscle atrophy in adult mice

PubMed Central

Zhang, Yiqiang; Davis, Carol; Sakellariou, George K.; Shi, Yun; Kayani, Anna C.; Pulliam, Daniel; Bhattacharya, Arunabh; Richardson, Arlan; Jackson, Malcolm J.; McArdle, Anne; Brooks, Susan V.; Van Remmen, Holly

2013-01-01

We have previously shown that deletion of CuZnSOD in mice (Sod1−/− mice) leads to accelerated loss of muscle mass and contractile force during aging. To dissect the relative roles of skeletal muscle and motor neurons in this process, we used a Cre-Lox targeted approach to establish a skeletal muscle-specific Sod1-knockout (mKO) mouse to determine whether muscle-specific CuZnSOD deletion is sufficient to cause muscle atrophy. Surprisingly, mKO mice maintain muscle masses at or above those of wild-type control mice up to 18 mo of age. In contrast, maximum isometric specific force measured in gastrocnemius muscle is significantly reduced in the mKO mice. We found no detectable increases in global measures of oxidative stress or ROS production, no reduction in mitochondrial ATP production, and no induction of adaptive stress responses in muscle from mKO mice. However, Akt-mTOR signaling is elevated and the number of muscle fibers with centrally located nuclei is increased in skeletal muscle from mKO mice, which suggests elevated regenerative pathways. Our data demonstrate that lack of CuZnSOD restricted to skeletal muscle does not lead to muscle atrophy but does cause muscle weakness in adult mice and suggest loss of CuZnSOD may potentiate muscle regenerative pathways.—Zhang, Y., Davis, C., Sakellariou, G.K., Shi, Y., Kayani, A.C., Pulliam, D., Bhattacharya, A., Richardson, A., Jackson, M.J., McArdle, A., Brooks, S.V., Van Remmen, H. CuZnSOD gene deletion targeted to skeletal muscle leads to loss of contractile force but does not cause muscle atrophy in adult mice. PMID:23729587

Selective digestive and oropharyngeal decontamination in medical and surgical ICU patients: individual patient data meta-analysis.

PubMed

Plantinga, N L; de Smet, A M G A; Oostdijk, E A N; de Jonge, E; Camus, C; Krueger, W A; Bergmans, D; Reitsma, J B; Bonten, M J M

2018-05-01

Selective digestive decontamination (SDD) and selective oropharyngeal decontamination (SOD) improved intensive care unit (ICU), hospital and 28-day survival in ICUs with low levels of antibiotic resistance. Yet it is unclear whether the effect differs between medical and surgical ICU patients. In an individual patient data meta-analysis, we systematically searched PubMed and included all randomized controlled studies published since 2000. We performed a two-stage meta-analysis with separate logistic regression models per study and per outcome (hospital survival and ICU survival) and subsequent pooling of main and interaction effects. Six studies, all performed in countries with low levels of antibiotic resistance, yielded 16 528 hospital admissions and 17 884 ICU admissions for complete case analysis. Compared to standard care or placebo, the pooled adjusted odds ratios for hospital mortality was 0.82 (95% confidence interval (CI) 0.72-0.93) for SDD and 0.84 (95% CI 0.73-0.97) for SOD. Compared to SOD, the adjusted odds ratio for hospital mortality was 0.90 (95% CI 0.82-0.97) for SDD. The effects on hospital mortality were not modified by type of ICU admission (p values for interaction terms were 0.66 for SDD and control, 0.87 for SOD and control and 0.47 for SDD and SOD). Similar results were found for ICU mortality. In ICUs with low levels of antibiotic resistance, the effectiveness of SDD and SOD was not modified by type of ICU admission. SDD and SOD improved hospital and ICU survival compared to standard care in both patient populations, with SDD being more effective than SOD. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Delayed Disease Onset and Extended Survival in the SOD1G93A Rat Model of Amyotrophic Lateral Sclerosis after Suppression of Mutant SOD1 in the Motor Cortex

PubMed Central

Thomsen, Gretchen M.; Gowing, Genevieve; Latter, Jessica; Chen, Maximus; Vit, Jean-Philippe; Staggenborg, Kevin; Avalos, Pablo; Alkaslasi, Mor; Ferraiuolo, Laura; Likhite, Shibi; Kaspar, Brian K.

2014-01-01

Sporadic amyotrophic lateral sclerosis (ALS) is a fatal disease with unknown etiology, characterized by a progressive loss of motor neurons leading to paralysis and death typically within 3–5 years of onset. Recently, there has been remarkable progress in understanding inherited forms of ALS in which well defined mutations are known to cause the disease. Rodent models in which the superoxide dismutase-1 (SOD1) mutation is overexpressed recapitulate hallmark signs of ALS in patients. Early anatomical changes in mouse models of fALS are seen in the neuromuscular junctions (NMJs) and lower motor neurons, and selective reduction of toxic mutant SOD1 in the spinal cord and muscle of these models has beneficial effects. Therefore, much of ALS research has focused on spinal motor neuron and NMJ aspects of the disease. Here we show that, in the SOD1G93A rat model of ALS, spinal motor neuron loss occurs presymptomatically and before degeneration of ventral root axons and denervation of NMJs. Although overt cell death of corticospinal motor neurons does not occur until disease endpoint, we wanted to establish whether the upper motor neuron might still play a critical role in disease progression. Surprisingly, the knockdown of mutant SOD1 in only the motor cortex of presymptomatic SOD1G93A rats through targeted delivery of AAV9–SOD1–shRNA resulted in a significant delay of disease onset, expansion of lifespan, enhanced survival of spinal motor neurons, and maintenance of NMJs. This datum suggests an early dysfunction and thus an important role of the upper motor neuron in this animal model of ALS and perhaps patients with the disease. PMID:25411487

Effect of rMnSOD on Sodium Reabsorption in Renal Proximal Tubule in Ochratoxin A-Treated Rats.

PubMed

Damiano, Sara; Puzio, Maria V; Squillacioti, Caterina; Mirabella, Nicola; Zona, Enrica; Mancini, Aldo; Borrelli, Antonella; Astarita, Carlo; Boffo, Silvia; Giordano, Antonio; Avallone, Luigi; Florio, Salvatore; Ciarcia, Roberto

2018-01-01

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium that represent toxic real threat for human beings and animal health. In this study we evaluated the effect of a new recombinant mitochondrial manganese containing superoxide dismutase (rMnSOD) on oxidative stress and on the alterations of fluid reabsorption in renal proximal tubule (PT) as possible causes of OTA nephrotoxicity. Finally, we have measured the concentration of O 2 - in the kidney through dihydroethidium assay (DHE) and nitric oxide (NO) concentration through nitrites and nitrates assay. Male Sprague Dawley rats weighing 120-150 g were treated for 14 days by gavage, as follows: Control group, 12 rats received a corresponding amount of saline solution (including 10% DMSO); rMnSOD group, 12 rats treated with rMnSOD (10 µg/kg bw); OTA group, 12 rats treated with OTA (0.5 mg/kg bw) dissolved in 10% DMSO and then scaled to required volume with corn oil; rMnSOD + OTA, 12 rats treated with rMnSOD (10 µg/kg bw) plus OTA (0.5 mg/kg bw). Our results have shown that rMnSOD restores the alteration of reabsorption in PT in rats treated with OTA plus rMnSOD, probably through the response to pressure natriuresis, where nitric oxide plays a key role. Moreover, rMnSOD prevents the nephrotoxicity induced by OTA probably restoring the balance between superoxide and NO that is most probably the cause of hypertension and renal functional alterations through the inhibition of NO synthase. In conclusion these data provide important information for understanding of mechanism of toxic action of OTA. J. Cell. Biochem. 119: 424-430, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Effect of ischemic preconditioning on antioxidant status in the gerbil hippocampal CA1 region after transient forebrain ischemia

PubMed Central

Park, Seung Min; Park, Chan Woo; Lee, Tae-Kyeong; Cho, Jeong Hwi; Park, Joon Ha; Lee, Jae-Chul; Chen, Bai Hui; Shin, Bich-Na; Ahn, Ji Hyeon; Tae, Hyun-Jin; Shin, Myoung Cheol; Ohk, Taek Geun; Cho, Jun Hwi; Won, Moo-Ho; Choi, Soo Young; Kim, In Hye

2016-01-01

Ischemic preconditioning (IPC) is a condition of sublethal transient global ischemia and exhibits neuroprotective effects against subsequent lethal ischemic insult. We, in this study, examined the neuroprotective effects of IPC and its effects on immunoreactive changes of antioxidant enzymes including superoxide dismutase (SOD) 1 and SOD2, catalase (CAT) and glutathione peroxidase (GPX) in the gerbil hippocampal CA1 region after transient forebrain ischemia. Pyramidal neurons of the stratum pyramidale (SP) in the hippocampal CA1 region of animals died 5 days after lethal transient ischemia without IPC (8.6% (ratio of remanent neurons) of the sham-operated group); however, IPC prevented the pyramidal neurons from subsequent lethal ischemic injury (92.3% (ratio of remanent neurons) of the sham-operated group). SOD1, SOD2, CAT and GPX immunoreactivities in the sham-operated animals were easily detected in pyramidal neurons in the stratum pyramidale (SP) of the hippocampal CA1 region, while all of these immunoreactivities were rarely detected in the stratum pyramidale at 5 days after lethal transient ischemia without IPC. Meanwhile, their immunoreactivities in the sham-operated animals with IPC were similar to (SOD1, SOD2 and CAT) or higher (GPX) than those in the sham-operated animals without IPC. Furthermore, their immunoreactivities in the stratum pyramidale of the ischemia-operated animals with IPC were steadily maintained after lethal ischemia/reperfusion. Results of western blot analysis for SOD1, SOD2, CAT and GPX were similar to immunohistochemical data. In conclusion, IPC maintained or increased the expression of antioxidant enzymes in the stratum pyramidale of the hippocampal CA1 region after subsequent lethal transient forebrain ischemia and IPC exhibited neuroprotective effects in the hippocampal CA1 region against transient forebrain ischemia. PMID:27630689

Uncoupling of oxidative stress resistance and lifespan in long-lived isp-1 mitochondrial mutants in Caenorhabditis elegans.

PubMed

Dues, Dylan J; Schaar, Claire E; Johnson, Benjamin K; Bowman, Megan J; Winn, Mary E; Senchuk, Megan M; Van Raamsdonk, Jeremy M

2017-07-01

Mutations affecting components of the mitochondrial electron transport chain have been shown to increase lifespan in multiple species including the worm Caenorhabditis elegans. While it was originally proposed that decreased generation of reactive oxygen species (ROS) resulting from lower rates of electron transport could account for the observed increase in lifespan, recent evidence indicates that ROS levels are increased in at least some of these long-lived mitochondrial mutants. Here, we show that the long-lived mitochondrial mutant isp-1 worms have increased resistance to oxidative stress. Our results suggest that elevated ROS levels in isp-1 worms cause the activation of multiple stress-response pathways including the mitochondrial unfolded protein response, the SKN-1-mediated stress response, and the hypoxia response. In addition, these worms have increased expression of specific antioxidant enzymes, including a marked upregulation of the inducible superoxide dismutase genes sod-3 and sod-5. Examining the contribution of sod-3 and sod-5 to the oxidative stress resistance in isp-1 worms revealed that loss of either of these genes increased resistance to oxidative stress, but not other forms of stress. Deletion of sod-3 or sod-5 decreased the lifespan of isp-1 worms and further exacerbated their slow physiologic rates. Thus, while deletion of sod-3 and sod-5 genes has little impact on stress resistance, physiologic rates or lifespan in wild-type worms, these genes are required for the longevity of isp-1 worms. Overall, this work shows that the increased resistance to oxidative stress in isp-1 worms does not account for their longevity, and that resistance to oxidative stress can be experimentally dissociated from lifespan. Copyright © 2017 Elsevier Inc. All rights reserved.

Hippophae rhamnoides L. leaves extract enhances cell proliferation and neuroblast differentiation through upregulation of intrinsic factors in the dentate gyrus of the aged gerbil.

PubMed

Ahn, Ji Hyeon; Chen, Bai Hui; Park, Joon Ha; Kim, In Hye; Cho, Jeong-Hwi; Lee, Jae-Chul; Yan, Bing Chun; Choi, Jung Hoon; Hwang, In Koo; Park, Ju-Hee; Han, Sang-No; Lee, Yun Lyul; Kim, Myong Jo; Won, Moo-Ho

2014-01-01

Hippophae rhamnoides L. (HL) exerts antioxidant activities against various oxidative stress conditions. In this study, we investigated effects of extract from HL leaves (HLE) on cell proliferation and neuroblast differentiation in the subgranular zone (SGZ) of the dentate gyrus (DG) of aged gerbils. Aged gerbils (24 months) were divided into vehicle (saline)-treated- and HLE-treated-groups. The vehicle and HLE were orally administered with 200 mg/kg once a day for 20 days before sacrifice. Cell proliferation and neuroblast differentiation were examined in the DG using Ki67 and doublecortin (DCX), respectively. We also observed changes in immunoreactivities of superoxide dismutase 1 (SOD1) and superoxide dismutase 2 (SOD2), brain-derived neurotrophic factor (BDNF), and phospho-glycogen synthase kinase-3-beta (p-GSK-3β) to examine their relation with neurogenesis using immunohistochemistry. The administration of HLE significantly increased the number of Ki67-positive cells and DCX-positive neuroblasts with well-developed processes in the SGZ of the DG of the HLE-treated-group. In addition, immunoreactivities of SOD1, SOD2, BDNF, and p-GSK-3β were significantly increased in granule and polymorphic cells of the DG in the HLE-treated-group compared with those in the vehicle-treated-group. HLE treatment significantly increased cell proliferation and neuroblast differentiation, showing that immunoreactivities of SOD1, SOD2, BDNF, and p-GSK-3β were significantly increased in the DG. These indicate that increased neuroblast differentiation neurogenesis may be closely related to upregulation of SOD1, SOD2, BDNF, and p-GSK-3β in aged gerbils.

L'effet de la superoxyde dismutase sur le système nerveux central irradié à propos d'études pilotes expérimentales chez le rat

NASA Astrophysics Data System (ADS)

Baillet, F.; Lamproglou, I.; Boisserie, G.

1998-04-01

It has been observed that bovine superoxide dismutase (SOD) can reduce some chronic complications due to radiotherapy. For this reason this enzyme has been used in the rat to treat radiation induced encaphalitis, studied by the two-way avoidance test. SOD has allowed significant regression of troubles in two studies with chronic encephalitis and two studies with acute encephalitis. Moreover, another study has shown that SOD prevented cognitival troubles brought on by strong painful stimulus. Thus SOD has been shown able to improve cerebral performances after a specific aggression (after radiotherapy) or after a non specific one (after very painful stimulus). This observation leads to interesting prospects for therapy. Il a été constaté que la superoxyde dismutase bovine (SOD) pouvait faire régresser certaines complications chroniques de la radiothérapie. Pour cette raison cette enzyme a été utilisée chez le rat pour traiter des encéphalites radiques étudiées par le test de l'évitement actif bilatéral. La SOD a permis une régression significative des troubles dans deux études d'encéphalite chronique et deux études d'encéphalite aiguë. Par ailleurs une autre étude a montré que la SOD prévenait les troubles cognitifs engendrés par un stimulus douloureux important. Ainsi la SOD s'est révélée capable d'améliorer les performances cérébrales après une agression spécifique (radiothérapie) ou non spécifique (stimulus douloureux important). Cette constatation ouvre des perspectives intéressantes pour la thérapeutique.

Antioxidant-Chemoprevention Diet Ameliorates Late Effects of Total-Body Irradiation and Supplements Radioprotection by MnSOD-Plasmid Liposome Administration

PubMed Central

Epperly, Michael W.; Wang, Hong; Jones, Jeffrey A.; Dixon, Tracy; Montesinos, Carlos A.; Greenberger, Joel S.

2011-01-01

Many acute and chronic effects of ionizing radiation are mediated by reactive oxygen species and reactive nitrogen species, which deplete antioxidant stores, leading to cellular apoptosis, stem cell depletion and accelerated aging. C57BL/6NHsd mice receiving intravenous MnSOD-PL prior to 9.5 Gy total-body irradiation (TBI) show increased survival from the acute hematopoietic syndrome, and males demonstrated improved long-term survival (Epperly et al., Radiat. Res. 170, 437–444, 2008). We evaluated the effect of an antioxidant-chemopreventive diet compared to a regular diet on long-term survival in female mice. Twenty-four hours before the LD50/30 dose of 9.5 Gy TBI, subgroups of mice were injected intravenously with MnSOD-PL (100 μg plasmid DNA in 100 μl of liposomes). Mice on either diet treated with MnSOD-PL showed decreased death after irradiation compared to irradiated mice on the house diet alone (P = 0.031 for the house diet plus MnSOD-PL or 0.015 for antioxidant diet plus MnSOD-PL). The mice on the antioxidant-chemoprevention diet alone or with MnSOD-PL that survived 30 days after irradiation had a significant increase in survival compared to mice on the regular diet (P = 0.04 or 0.01, respectively). In addition, mice treated with MnSOD-PL only and surviving 30 days after radiation also had increased survival compared to those on the regular diet alone (P = 0.02). Survivors of acute ionizing radiation damage have ameliorated life shortening if they are fed an antioxidant-chemopreventive diet. PMID:21466381

Comparison of the clinical and cognitive features of genetically positive ALS patients from the largest tertiary center in Serbia.

PubMed

Marjanović, Ivan V; Selak-Djokić, Biljana; Perić, Stojan; Janković, Milena; Arsenijević, Vladimir; Basta, Ivana; Lavrnić, Dragana; Stefanova, Elka; Stević, Zorica

2017-06-01

Discovering novel mutations in C9orf72, FUS, ANG, and TDP-43 genes in ALS patients arises necessities for better clinical characterizations of these subjects. The aim is to determine clinical and cognitive profile of genetically positive Serbian ALS patients. 241 ALS patients were included in the study (17 familiar and 224 apparently sporadic). The following genes were analyzed: SOD1, C9orf72, ANG, FUS, and TDP-43. An extensive battery of classic neuropsychological tests was used in 27 ALS patients (22 SOD1 positive and 5 SOD1 negative) and 82 healthy controls (HCs). Overall 37 (15.4%) of 241 ALS patients carried mutations in tested genes-among 17 familiar ALS patients 16 (94.1%) were positive and among 224 apparently sporadic 21 (9.4%) had causative mutation. Mutations in SOD1 gene were the most common, representing 27 (73.0%) of all genetically positive ALS patients. The main clinical characteristics of SOD1 positive patients were: spinal onset in lower extremities, common sphincter and sensitive disturbances, and dysexecutive syndrome. Within SOD1 positive patients, we noticed somewhat earlier onset in patients with A145G, sensory and sphincter disturbances were dominant in patients with L144F, while D90A patients had significant sensory involvement. SOD1 negative group consisted of ten (27.0%) patients (six C9orf72, two ANG, one TDP-43, and one patient baring triple FUS, C9orf72 expansion, and ANG variants). Bulbar involvement and more extensive neuropsychological impairment (including executive, visuospatial, and memory difficulties) were the main features of SOD1 negative cohort. Our results suggest that meaningful clinical suspicion of certain ALS genotype might be made based on thorough clinical evaluation of patients.

Superoxide Dismutase 1 In Vivo Ameliorates Maternal Diabetes Mellitus-Induced Apoptosis and Heart Defects Through Restoration of Impaired Wnt Signaling.

PubMed

Wang, Fang; Fisher, Steven A; Zhong, Jianxiang; Wu, Yanqing; Yang, Peixin

2015-10-01

Oxidative stress is manifested in embryos exposed to maternal diabetes mellitus, yet specific mechanisms for diabetes mellitus-induced heart defects are not defined. Gene deletion of intermediates of Wingless-related integration (Wnt) signaling causes heart defects similar to those observed in embryos from diabetic pregnancies. We tested the hypothesis that diabetes mellitus-induced oxidative stress impairs Wnt signaling, thereby causing heart defects, and that these defects can be rescued by transgenic overexpression of the reactive oxygen species scavenger superoxide dismutase 1 (SOD1). Wild-type (WT) and SOD1-overexpressing embryos from nondiabetic WT control dams and nondiabetic/diabetic WT female mice mated with SOD1 transgenic male mice were analyzed. No heart defects were observed in WT and SOD1 embryos under nondiabetic conditions. WT embryos of diabetic dams had a 26% incidence of cardiac outlet defects that were suppressed by SOD1 overexpression. Insulin treatment reduced blood glucose levels and heart defects. Diabetes mellitus increased superoxide production, canonical Wnt antagonist expression, caspase activation, and apoptosis and suppressed cell proliferation. Diabetes mellitus suppressed Wnt signaling intermediates and Wnt target gene expression in the embryonic heart, each of which were reversed by SOD1 overexpression. Hydrogen peroxide and peroxynitrite mimicked the inhibitory effect of high glucose on Wnt signaling, which was abolished by the SOD1 mimetic, tempol. The oxidative stress of diabetes mellitus impairs Wnt signaling and causes cardiac outlet defects that are rescued by SOD1 overexpression. This suggests that targeting of components of the Wnt5a signaling pathway may be a viable strategy for suppression of congenital heart defects in fetuses of diabetic pregnancies. © 2015 American Heart Association, Inc.

Decreased stability and increased formation of soluble aggregates by immature superoxide dismutase do not account for disease severity in ALS

PubMed Central

Vassall, Kenrick A.; Stubbs, Helen R.; Primmer, Heather A.; Tong, Ming Sze; Sullivan, Sarah M.; Sobering, Ryan; Srinivasan, Saipraveen; Briere, Lee-Ann K.; Dunn, Stanley D.; Colón, Wilfredo; Meiering, Elizabeth M.

2011-01-01

Protein aggregation is a hallmark of many diseases, including amyotrophic lateral sclerosis (ALS), where aggregation of Cu/Zn superoxide dismutase (SOD1) is implicated in causing neurodegeneration. Recent studies have suggested that destabilization and aggregation of the most immature form of SOD1, the disulfide-reduced, unmetallated (apo) protein is particularly important in causing ALS. We report herein in depth analyses of the effects of chemically and structurally diverse ALS-associated mutations on the stability and aggregation of reduced apo SOD1. In contrast with previous studies, we find that various reduced apo SOD1 mutants undergo highly reversible thermal denaturation with little aggregation, enabling quantitative thermodynamic stability analyses. In the absence of ALS-associated mutations, reduced apo SOD1 is marginally stable but predominantly folded. Mutations generally result in slight decreases to substantial increases in the fraction of unfolded protein. Calorimetry, ultracentrifugation, and light scattering show that all mutations enhance aggregation propensity, with the effects varying widely, from subtle increases in most cases, to pronounced formation of 40–100 nm soluble aggregates by A4V, a mutation that is associated with particularly short disease duration. Interestingly, although there is a correlation between observed aggregation and stability, there is minimal to no correlation between observed aggregation, predicted aggregation propensity, and disease characteristics. These findings suggest that reduced apo SOD1 does not play a dominant role in modulating disease. Rather, additional and/or multiple forms of SOD1 and additional biophysical and biological factors are needed to account for the toxicity of mutant SOD1 in ALS. PMID:21257910

Protective effects of intraperitoneal injection of TAT-SOD against focal cerebral ischemia/reperfusion injury in rats.

PubMed

Ye, Nanhui; Liu, Shutao; Lin, Yanyun; Rao, Pingfan

2011-12-05

The intracellular superoxide anion has been shown to be involved in brain injury. TAT-Superoxide dismutase (TAT-SOD) can be transduced across the cell membrane to scavenge superoxide. This protein's unique properties make it a promising therapeutic candidate to attenuate cerebral damage. In this study, we sought further the understanding of the fusion protein's cerebral protective effects and the mechanism which is exerted in these effects. Male Sprague Dawley rats (n=100, 230±20 g) were divided randomly into five experimental groups: a sham group, a cerebral Ischemia/Reperfusion (I/R) group treated with saline (20 ml/Kg, i.p.), and three cerebral I/R groups treated with TAT-SOD (25 KU/ml/Kg, i.p.) at either 2h before I/R, 2h after I/R or 4h after I/R. Cerebral I/R injury was facilitated by inducing ischemia for two hours followed by 24h reperfusion. The levels of SOD, Malondialdehyde (MDA), and ATPase in cerebral tissues were determined. The apoptotic indexes were evaluated, and apoptosis genes were analyzed immunohistochemically. TAT-SOD treatment significantly increased cerebral SOD and ATPase activities, decreased MDA content, and remarkably reduced apoptosis indexes. TAT-SOD treatments 2h before or after I/R significantly reduced caspase-3 and bax proteins and boosted bcl-2 protein, while the treatment at 4h after I/R showed no influence on the three proteins. TAT-SOD treatment effectively enhanced cerebral antioxidant ability, reduced lipid peroxidation, preserved mitochondrial ATPase and thus inhibited nerve cell apoptosis. The effective treatment window extended from 2h before to 2h after I/R. Copyright © 2011 Elsevier B.V. All rights reserved.

Defective mitochondrial dynamics is an early event in skeletal muscle of an amyotrophic lateral sclerosis mouse model.

PubMed

Luo, Guo; Yi, Jianxun; Ma, Changling; Xiao, Yajuan; Yi, Frank; Yu, Tian; Zhou, Jingsong

2013-01-01

Mitochondria are dynamic organelles that constantly undergo fusion and fission to maintain their normal functionality. Impairment of mitochondrial dynamics is implicated in various neurodegenerative disorders. Amyotrophic lateral sclerosis (ALS) is an adult-onset neuromuscular degenerative disorder characterized by motor neuron death and muscle atrophy. ALS onset and progression clearly involve motor neuron degeneration but accumulating evidence suggests primary muscle pathology may also be involved. Here, we examined mitochondrial dynamics in live skeletal muscle of an ALS mouse model (G93A) harboring a superoxide dismutase mutation (SOD1(G93A)). Using confocal microscopy combined with overexpression of mitochondria-targeted photoactivatable fluorescent proteins, we discovered abnormal mitochondrial dynamics in skeletal muscle of young G93A mice before disease onset. We further demonstrated that similar abnormalities in mitochondrial dynamics were induced by overexpression of mutant SOD1(G93A) in skeletal muscle of normal mice, indicating the SOD1 mutation drives ALS-like muscle pathology in the absence of motor neuron degeneration. Mutant SOD1(G93A) forms aggregates inside muscle mitochondria and leads to fragmentation of the mitochondrial network as well as mitochondrial depolarization. Partial depolarization of mitochondrial membrane potential in normal muscle by carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) caused abnormalities in mitochondrial dynamics similar to that in the SOD1(G93A) model muscle. A specific mitochondrial fission inhibitor (Mdivi-1) reversed the SOD1(G93A) action on mitochondrial dynamics, indicating SOD1(G93A) likely promotes mitochondrial fission process. Our results suggest that accumulation of mutant SOD1(G93A) inside mitochondria, depolarization of mitochondrial membrane potential and abnormal mitochondrial dynamics are causally linked and cause intrinsic muscle pathology, which occurs early in the course of ALS and may actively promote ALS progression.

Effects of tongue force training on bulbar motor function in the female SOD1-G93A rat model of Amyotrophic Lateral Sclerosis

PubMed Central

Ma, Delin; Shuler, Jeffrey M.; Kumar, Aishwarya; Stanford, Quincy R.; Tungtur, Sudheer; Nishimune, Hiroshi; Stanford, John A.

2016-01-01

Background The use of exercise in Amyotrophic Lateral Sclerosis (ALS) is controversial. Although moderate exercise appears to be beneficial for limb muscles in ALS, the effects of exercise on bulbar muscles such as the tongue have not been studied. Objective The aim of this study was to determine the effects of tongue force training on bulbar motor function in the SOD1-G93A rat model of ALS. Methods We compared the effects of tongue force training on bulbar motor function and neuromuscular junction (NMJ) innervation in female SOD1-G93A rats and age-matched female wild-type controls. Half of each group underwent afternoon tongue force training sessions, while all rats were tested under minimal force conditions in the mornings. Results Tongue force did not differ between the SOD1-G93A rats and healthy controls during the morning testing sessions, nor was it affected by training. Surprisingly, decreases in tongue motility, the number of licks per session, and body weight were greater in the tongue force-trained SOD1-G93A rats. Forelimb grip force, survival, and denervation of the genioglossus muscle did not differ between the trained and untrained SOD1-G93A rats. Genioglossus innervation was correlated with changes in tongue force but not tongue motility in SOD1-G93A rats at end stage. Conclusions The results indicate a potential deleterious effect of tongue force training on tongue motility in female SOD1-G93A rats. The lack of relationship between genioglossus innervation and tongue motility suggest that factors other than lower motor neuron integrity likely accounted for this effect. PMID:27573800

Rilmenidine promotes MTOR-independent autophagy in the mutant SOD1 mouse model of amyotrophic lateral sclerosis without slowing disease progression

PubMed Central

Perera, Nirma D.; Sheean, Rebecca K.; Lau, Chew L.; Shin, Yea Seul; Beart, Philip M.; Horne, Malcolm K.; Turner, Bradley J.

2018-01-01

ABSTRACT Macroautophagy/autophagy is the main intracellular catabolic pathway in neurons that eliminates misfolded proteins, aggregates and damaged organelles associated with ageing and neurodegeneration. Autophagy is regulated by both MTOR-dependent and -independent pathways. There is increasing evidence that autophagy is compromised in neurodegenerative disorders, which may contribute to cytoplasmic sequestration of aggregation-prone and toxic proteins in neurons. Genetic or pharmacological modulation of autophagy to promote clearance of misfolded proteins may be a promising therapeutic avenue for these disorders. Here, we demonstrate robust autophagy induction in motor neuronal cells expressing SOD1 or TARDBP/TDP-43 mutants linked to amyotrophic lateral sclerosis (ALS). Treatment of these cells with rilmenidine, an anti-hypertensive agent and imidazoline-1 receptor agonist that induces autophagy, promoted autophagic clearance of mutant SOD1 and efficient mitophagy. Rilmenidine administration to mutant SOD1G93A mice upregulated autophagy and mitophagy in spinal cord, leading to reduced soluble mutant SOD1 levels. Importantly, rilmenidine increased autophagosome abundance in motor neurons of SOD1G93A mice, suggesting a direct action on target cells. Despite robust induction of autophagy in vivo, rilmenidine worsened motor neuron degeneration and symptom progression in SOD1G93A mice. These effects were associated with increased accumulation and aggregation of insoluble and misfolded SOD1 species outside the autophagy pathway, and severe mitochondrial depletion in motor neurons of rilmenidine-treated mice. These findings suggest that rilmenidine treatment may drive disease progression and neurodegeneration in this mouse model due to excessive mitophagy, implying that alternative strategies to beneficially stimulate autophagy are warranted in ALS. PMID:28980850

Overexpression of human mutated G93A SOD1 changes dynamics of the ER mitochondria calcium cycle specifically in mouse embryonic motor neurons.

PubMed

Lautenschläger, Janin; Prell, Tino; Ruhmer, Julia; Weidemann, Lisa; Witte, Otto W; Grosskreutz, Julian

2013-09-01

Motor neurons vulnerable to the rapidly progressive deadly neurodegenerative disease amyotrophic lateral sclerosis (ALS) inherently express low amounts of calcium binding proteins (CaBP), likely to allow physiological motor neuron firing frequency modulation. At the same time motor neurons are susceptible to AMPA receptor mediated excitotoxicity and internal calcium deregulation which is not fully understood. We analysed ER mitochondria calcium cycle (ERMCC) dynamics with subsecond resolution in G93A hSOD1 overexpressing motor neurons as a model of ALS using fluorescent calcium imaging. When comparing vulnerable motor neurons and non-motor neurons from G93A hSOD1 mice and their non-transgenic littermates, we found a decelerated cytosolic calcium clearance in the presence of G93A hSOD1. While both non-transgenic as well as G93A hSOD1 motor neurons displayed large mitochondrial calcium uptake by the mitochondrial uniporter (mUP), the mitochondrial calcium extrusion system was altered in the presence of G93A hSOD1. In addition, ER calcium uptake by the sarco-/endoplasmic reticulum ATPase (SERCA) was increased in G93A hSOD1 motor neurons. In survival assays, blocking the mitochondrial sodium calcium exchanger (mNCE) by CGP37157 as well as inhibiting SERCA by cyclopiazonic acid showed protective effects against kainate induced excitotoxicity. Thus, our study shows for the first time that the functional consequence of G93A hSOD1 overexpression in intact motor neurons is indeed a disturbance of the ER mitochondria calcium cycle, and identified two promising targets for therapeutic intervention in the pathology of ALS. Copyright © 2013 Elsevier Inc. All rights reserved.

Two novel cyanobacterial bioluminescent whole-cell bioreporters based on superoxide dismutases MnSod and FeSod to detect superoxide anion.

PubMed

Hurtado-Gallego, J; Martín-Betancor, K; Rodea-Palomares, I; Leganés, F; Rosal, R; Fernández-Piñas, F

2018-06-01

This work describes the construction of two novel self-luminescent bioreporter strains of the cyanobacterium Nostoc sp. PCC 7120 by fusing the promoter region of the sodA and sodB genes (encoding the superoxide dismutases MnSod and FeSod, respectively) to luxCDABE from Photorhabdus luminescens aimed at detecting pollutants that generate reactive oxygen species (ROS), particularly O 2 - . Bioreporters were tested against methyl viologen (MV) as the inducer of superoxide anion (O 2 - ). Both bioreporters were specific for O 2 - and Limits of detection (LODs) and Maximum Permissive Concentrations (MPCs) were calculated: Nostoc sp. PCC 7120 pBG2154 (sodA) had a range of detection from 400 to 1000 pM of MV and for Nostoc sp. PCC 7120 pBG2165 (sodB) the range of detection was from 500 to 1800 pM of MV after 5 h-exposure. To further validate the bioreporters, they were tested with the emerging pollutant Triclosan which induced bioluminescence in both strains. Furthermore, the bioreporters performance was tested in two real environmental samples with different water matrix complexity, spiked with MV. Both bioreporters were induced by O 2 - in these environmental samples. In the case of the river water sample, the amount of bioavailable MV as calculated from the bioreporters output was similar to that nominally added. For the waste water sample, the bioavailable MV concentration detected by the bioreporters was one order of magnitude lower than nominal. These differences could be due to MV complexation with organic matter and/or co-occurring organic contaminants. These results confirm their high sensitivity to O 2 - and their suitability to detect oxidative stress-generating pollutants in fresh-waters. Copyright © 2018 Elsevier Ltd. All rights reserved.

Molecular Control of TiO2-NPs Toxicity Formation at Predicted Environmental Relevant Concentrations by Mn-SODs Proteins

PubMed Central

Wu, Qiuli; Li, Yiping; Tang, Meng; Ye, Boping; Wang, Dayong

2012-01-01

With growing concerns of the safety of nanotechnology, the in vivo toxicity of nanoparticles (NPs) at environmental relevant concentrations has drawn increasing attentions. We investigated the possible molecular mechanisms of titanium nanoparticles (Ti-NPs) in the induction of toxicity at predicted environmental relevant concentrations. In nematodes, small sizes (4 nm and 10 nm) of TiO2-NPs induced more severe toxicities than large sizes (60 nm and 90 nm) of TiO2-NPs on animals using lethality, growth, reproduction, locomotion behavior, intestinal autofluorescence, and reactive oxygen species (ROS) production as endpoints. Locomotion behaviors could be significantly decreased by exposure to 4-nm and 10-nm TiO2-NPs at concentration of 1 ng/L in nematodes. Among genes required for the control of oxidative stress, only the expression patterns of sod-2 and sod-3 genes encoding Mn-SODs in animals exposed to small sizes of TiO2-NPs were significantly different from those in animals exposed to large sizes of TiO2-NPs. sod-2 and sod-3 gene expressions were closely correlated with lethality, growth, reproduction, locomotion behavior, intestinal autofluorescence, and ROS production in TiO2-NPs-exposed animals. Ectopically expression of human and nematode Mn-SODs genes effectively prevented the induction of ROS production and the development of toxicity of TiO2-NPs. Therefore, the altered expression patterns of Mn-SODs may explain the toxicity formation for different sizes of TiO2-NPs at predicted environmental relevant concentrations. In addition, we demonstrated here a strategy to investigate the toxicological effects of exposure to NPs upon humans by generating transgenic strains in nematodes for specific human genes. PMID:22973466

A Cystine-Rich Whey Supplement (Immunocal®) Delays Disease Onset and Prevents Spinal Cord Glutathione Depletion in the hSOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis

PubMed Central

Ross, Erika K.; Winter, Aimee N.; Wilkins, Heather M.; Sumner, Whitney A.; Duval, Nathan; Patterson, David; Linseman, Daniel A.

2014-01-01

Depletion of the endogenous antioxidant, glutathione (GSH), underlies progression of the devastating neurodegenerative disease, amyotrophic lateral sclerosis (ALS). Thus, strategies aimed at elevating GSH may yield new therapeutics for ALS. Here, we investigated the effects of a unique non-denatured whey protein supplement, Immunocal®, in the transgenic Gly position 93 to Ala (G93A) mutant hSOD1 (hSOD1G93A) mouse model of ALS. Immunocal® is rich in the GSH precursor, cystine, and is therefore capable of bolstering GSH content. Transgenic hSOD1G93A mice receiving Immunocal® displayed a significant delay in disease onset compared to untreated hSOD1G93A controls. Additionally, Immunocal® treatment significantly decreased the rate of decline in grip strength and prevented disease-associated reductions in whole blood and spinal cord tissue GSH levels in end-stage hSOD1G93A mice. However, Immunocal® did not extend survival, likely due to its inability to preserve the mitochondrial GSH pool in spinal cord. Combination treatment with Immunocal® and the anti-glutamatergic compound, riluzole, delayed disease onset and extended survival in hSOD1G93A mice. These findings demonstrate that sustaining tissue GSH with Immunocal® only modestly delays disease onset and slows the loss of skeletal muscle strength in hSOD1G93A mice. Moreover, the inability of Immunocal® to rescue mitochondrial GSH in spinal cord provides a possible mechanism for its lack of effect on survival and is a limiting factor in the potential utility of this supplement as a therapeutic for ALS. PMID:26785244

Adaptive flexibility of enzymatic antioxidants SOD, APX and CAT to high light stress: The clonal perennial monocot Iris pumila as a study case.

PubMed

Vuleta, Ana; Manitašević Jovanović, Sanja; Tucić, Branka

2016-03-01

High solar radiation has been recognized as one of the main causes of the overproduction of reactive oxygen species (ROS) and oxidative stress in plants. To remove the excess of ROS, plants use different antioxidants and tune their activity and/or isoform number as required for given light conditions. In this study, the adaptiveness of light-induced variation in the activities and isoform patterns of key enzymatic antioxidants SOD, APX and CAT was tested in leaves of Iris pumila clonal plants from two natural populations inhabiting a sun exposed dune site and a forest understory, using a reciprocal-transplant experiment. At the exposed habitat, the mean enzymatic activity of total SODs was significantly greater than that in the shaded one, while the amount of the mitochondrial MnSOD was notably higher compared to the plastidic Cu/ZnSOD. However, the number of Cu/ZnSOD isoforms was greater in the forest understory relative to the exposed site (three vs. two, respectively). An inverse relationship recorded between the quantities of MnSOD and Cu/ZnSOD in alternative light habitats might indicate that the two enzymes compensate each other in maintaining intracellular ROS and redox balance. The adaptive population differentiation in APX activity was exclusively recorded in the open habitat, which indicated that the synergistic effect of high light and temperature stress could be the principal selective factor, rather than high light alone. The enzymatic activity of CAT was similar between the two populations, implicating APX as the primary H2O2 scavenger in the I. pumila leaves exposed to high light intensity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Computational investigation of the human SOD1 mutant, Cys146Arg, that directs familial amyotrophic lateral sclerosis.

PubMed

Srinivasan, E; Rajasekaran, R

2017-07-25

The genetic substitution mutation of Cys146Arg in the SOD1 protein is predominantly found in the Japanese population suffering from familial amyotrophic lateral sclerosis (FALS). A complete study of the biophysical aspects of this particular missense mutation through conformational analysis and producing free energy landscapes could provide an insight into the pathogenic mechanism of ALS disease. In this study, we utilized general molecular dynamics simulations along with computational predictions to assess the structural characterization of the protein as well as the conformational preferences of monomeric wild type and mutant SOD1. Our static analysis, accomplished through multiple programs, predicted the deleterious and destabilizing effect of mutant SOD1. Subsequently, comparative molecular dynamic studies performed on the wild type and mutant SOD1 indicated a loss in the protein conformational stability and flexibility. We observed the mutational consequences not only in local but also in long-range variations in the structural properties of the SOD1 protein. Long-range intramolecular protein interactions decrease upon mutation, resulting in less compact structures in the mutant protein rather than in the wild type, suggesting that the mutant structures are less stable than the wild type SOD1. We also presented the free energy landscape to study the collective motion of protein conformations through principal component analysis for the wild type and mutant SOD1. Overall, the study assisted in revealing the cause of the structural destabilization and protein misfolding via structural characterization, secondary structure composition and free energy landscapes. Hence, the computational framework in our study provides a valuable direction for the search for the cure against fatal FALS.

Gene Therapy With Extracellular Superoxide Dismutase Protects Conscious Rabbits Against Myocardial Infarction

PubMed Central

Li, Qianhong; Bolli, Roberto; Qiu, Yumin; Tang, Xian-Liang; Guo, Yiru; French, Brent A.

2013-01-01

Background Extracellular superoxide dismutase (Ec-SOD) may protect the heart against myocardial infarction (MI) because of its extended half-life and capacity to bind heparan sulfate proteoglycans on cellular surfaces. Accordingly, we used direct gene transfer to increase systemic levels of Ec-SOD and determined whether this gene therapy could protect against MI. Methods and Results The cDNA for human Ec-SOD was incorporated into a replication-deficient adenovirus (Ad5/CMV/Ec-SOD). Injection of this virus produced a high level of Ec-SOD in the liver, which was redistributed to the heart and other organs by injection of heparin. Untreated rabbits (group I) underwent a 30-minute coronary occlusion and 3 days of reperfusion. For comparison, preconditioned rabbits (group II) underwent a sequence of six 4-minute-occlusion/4-minute-reperfusion cycles 24 hours before the 30-minute occlusion. Control-treated rabbits (group III) were injected intravenously with Ad5/CMV/nls-LacZ, and gene-therapy rabbits (group IV) were injected with Ad5/CMV/Ec-SOD 3 days before the 30-minute occlusion. Both groups treated with Ad5 received intravenous heparin 2 hours before the 30-minute occlusion. Infarct size (percent risk area) was similar in groups I (57±6%) and III (58±5%). Ec-SOD gene therapy markedly reduced infarct size to 25±4% (P<0.01, group IV versus group III), a protection comparable to that of the late phase of ischemic preconditioning (29±3%, P<0.01 group II versus group I). Conclusions Direct gene transfer of the cDNA encoding membrane-bound Ec-SOD affords powerful cardioprotection, providing proof of principle for the effectiveness of antioxidant gene therapy against MI. PMID:11294809

Superoxide dismutase from Trichuris ovis--inhibition by benzimidazoles and pyrimidine derivatives.

PubMed

Sanchez-Moreno, M; Garcia-Rejon, L; Salas, I; Osuna, A; Monteoliva, M

1992-01-01

Three superoxide dismutase isoenzymes of different cellular location were detected in an homogenate of Trichuris ovis. Each of these molecular forms was purified by differential centrifugation and precipitation with ammonium sulphate, followed by chromatography on DEAE-cellulose and Sephadex G-75 columns. The activity levels of the two molecular forms detected in the mitochondrial (one cyanide sensitive Cu-Zn-SOD and the other cyanide insensitive Mn-SOD) were higher than that of the superoxide dismutase detected in the cytoplasmic fraction (cyanide sensitive Cu-Zn-SOD). All molecular forms present evident differences to the SODs contained in the host liver. Molecular mass and some of the physical and chemical properties of the enzyme was determined for all three molecular forms. An inhibitory effect on the SOD of the parasite an the host was detected with a series of compounds, some of which markedly inhibited parasite enzyme but not host enzyme.

Sphincter of Oddi Function and Risk Factors for Dysfunction

PubMed Central

Afghani, Elham; Lo, Simon K.; Covington, Paul S.; Cash, Brooks D.; Pandol, Stephen J.

2017-01-01

The sphincter of Oddi (SO) is a smooth muscle valve regulating the flow of biliary and pancreatic secretions into the duodenum, initially described in 1887 by the Italian anatomist, Ruggero Oddi. SO dysfunction (SOD) is a broad term referring to numerous biliary, pancreatic, and hepatic disorders resulting from spasms, strictures, and relaxation of this valve at inappropriate times. This review brings attention to various factors that may increase the risk of SOD, including but not limited to: cholecystectomy, opiates, and alcohol. Lack of proper recognition and treatment of SOD may be associated with clinical events, including pancreatitis and biliary symptoms with hepatic enzyme elevation. Pharmacologic and non-pharmacologic approaches are discussed to help recognize, prevent, and treat SOD. Future studies are needed to assess the treatment benefit of agents such as calcium-channel blockers, glyceryl trinitrate, or tricyclic antidepressants in patients with SOD. PMID:28194398

Sphincter of Oddi Function and Risk Factors for Dysfunction.

PubMed

Afghani, Elham; Lo, Simon K; Covington, Paul S; Cash, Brooks D; Pandol, Stephen J

2017-01-01

The sphincter of Oddi (SO) is a smooth muscle valve regulating the flow of biliary and pancreatic secretions into the duodenum, initially described in 1887 by the Italian anatomist, Ruggero Oddi. SO dysfunction (SOD) is a broad term referring to numerous biliary, pancreatic, and hepatic disorders resulting from spasms, strictures, and relaxation of this valve at inappropriate times. This review brings attention to various factors that may increase the risk of SOD, including but not limited to: cholecystectomy, opiates, and alcohol. Lack of proper recognition and treatment of SOD may be associated with clinical events, including pancreatitis and biliary symptoms with hepatic enzyme elevation. Pharmacologic and non-pharmacologic approaches are discussed to help recognize, prevent, and treat SOD. Future studies are needed to assess the treatment benefit of agents such as calcium-channel blockers, glyceryl trinitrate, or tricyclic antidepressants in patients with SOD.

Nucleotide sequence of a complementary DNA encoding pea cytosolic copper/zinc superoxide dismutase. [Pisum sativum L

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, D.A.; Zilinskas, B.A.

1991-08-01

The authors now report the nucleotide sequence of the cytosolic Cu/Zn SOD cloned from a {lambda}gt11 cDNA library constructed from mRNA extracted from leaves of 7- to 10-d pea seedlings (Pisum sativum L.). The clone was isolated using a 22-base synthetic oligonucleotide complementary to the amino acid sequence CGIIGLQG. This sequence, found at the protein's carboxy terminus, is highly conserved among plant cytosolic Cu/Zn SODs but not chloroplastic Cu/Zn SODs. The 738-base pair sequence contains an open reading frame specifying 152 codons and a predicted M{sub r} of 18,024 D. The deduced amino acid sequence is highly homologous (79-82% identity)more » with the sequences of other known plant cytosolic Cu/Zn SODs but less highly conserved (63-65%) when compared with several chloroplastic Cu/Zn SODs including pea (10).« less

The OakMapper WebGIS: improved access to sudden oak death spatial data

Treesearch

K. Tuxen; M. Kelly

2008-01-01

Access to timely and accurate sudden oak death (SOD) location data is critical for SOD monitoring, management and research. Several websites (hereafter called the OakMapper sites) associated with sudden oak death monitoring efforts have been maintained with up-todate SOD location information for over five years, providing information and maps of the most current...

Novel approaches to SOD management in California wildlands: a case study of "eradication" and collaboration in Redwood Valley

Treesearch

Y. Valachovic; L. Quinn-Davidson; E. Goldsworthy; P. Cannon

2013-01-01

In California, sudden oak death (SOD) treatment efforts have been localized, often targeting specific trees or properties. The widespread nature of SOD establishment and spread in coastal mountains of California has mostly precluded use of broader eradication strategies, which are more applicable in isolated infestations like those in Oregon. However, the 2010...

Partial sequencing of sodA gene and its application to identification of Streptococcus dysgalactiae subsp. dysgalactiae isolated from farmed fish.

PubMed

Nomoto, R; Kagawa, H; Yoshida, T

2008-01-01

To investigate the difference between Lancefield group C Streptococcus dysgalactiae (GCSD) strains isolated from diseased fish and animals by sequencing and phylogenetic analysis of the sodA gene. The sodA gene of Strep. dysgalactiae strains isolated from fish and animals were amplified and its nucleotide sequences were determined. Although 100% sequence identity was observed among fish GCSD strains, the determined sequences from animal isolates showed variations against fish isolate sequences. Thus, all fish GCSD strains were clearly separated from the GCSD strains of other origin by using phylogenetic tree analysis. In addition, the original primer set was designed based on the determined sequences for specifically amplify the sodA gene of fish GCSD strains. The primer set yield amplification products from only fish GCSD strains. By sequencing analysis of the sodA gene, the genetic divergence between Strep. dysgalactiae strains isolated from fish and mammals was demonstrated. Moreover, an original oligonucletide primer set, which could simply detect the genotype of fish GCSD strains was designed. This study shows that Strep. dysgalactiae isolated from diseased fish could be distinguished from conventional GCSD strains by the difference in the sequence of the sodA gene.

Physical and chemical stability of different formulations with superoxide dismutase.

PubMed

Di Mambro, V M; Campos, P M B G Maia; Fonseca, M J V

2004-10-01

Topical formulations with superoxide dismutase (SOD), a scavenger of superoxide radicals, have proved to be effective against some skin diseases. Nevertheless, formulations with proteins are susceptible to both chemical and physical instability. Three different formulations (anionic and non-ionic gel and emulsion) were developed and supplemented with SOD in order to determine the most stable formulation that would maintain SOD activity. Physical stability was evaluated by assessing the rheological behavior of the formulations stored at room temperature, 37 and 45 degrees C. Chemical stability was evaluated by the measurement of enzymatic activity in the formulations stored at room temperature and at 45 degrees C. Formulations showed a flow index less than one, characterizing pseudoplastic behavior. There was no significant difference in initial values of flow index, tixotropy or minimum apparent viscosity. Neither gel showed significant changes in minimum apparent viscosity concerning storage time or temperature, as well, SOD presence and its activity. The emulsion showed decreased viscosity by the 28th day, but no significant changes concerning storage temperature or SOD presence, although it showed a decreased activity. The addition of SOD to the formulations studied did not affect their physical stability but gel formulations seem to be better bases for enzyme addition.

Superoxide dismutase: a predicting factor for boar semen characteristics for short-term preservation.

PubMed

Zakošek Pipan, Maja; Mrkun, Janko; Kosec, Marjan; Nemec Svete, Alenka; Zrimšek, Petra

2014-01-01

Superoxide dismutase (SOD), total antioxidant capacity (TAC), and thiobarbituric acid reactive substances (TBARS) in seminal plasma were evaluated on the basis of receiver operating characteristics (ROC) analysis as predictors for distinguishing satisfactory from unsatisfactory boar semen samples after storage. SOD on day 0 correlated significantly with progressive motility (r=-0.686; P<0.05) and viability (r=-0.513; P<0.05) after storage; TBARS correlated only with motility (r=-0.480; P<0.05). Semen samples that, after 3 days of storage, fulfilled all criteria for semen characteristics (viability>85%, motility>70%, progressive motility>25%, and normal morphology>50%) had significantly lower SOD levels on the day 0 than those with at least one criterion not fulfilled (P<0.05) following storage. SOD levels of less than 1.05 U/mL predicted with 87.5% accuracy that fresh semen will suit the requirements for satisfactory semen characteristics after storage, while semen with SOD levels higher than 1.05 U/mL will not fulfill with 100% accuracy at least one semen characteristic after storage. These results support the proposal that SOD in fresh boar semen can be used as a predictor of semen quality after storage.

Regulation of Intracellular Copper by Induction of Endogenous Metallothioneins Improves the Disease Course in a Mouse Model of Amyotrophic Lateral Sclerosis.

PubMed

Tokuda, Eiichi; Watanabe, Shunsuke; Okawa, Eriko; Ono, Shin-ichi

2015-04-01

Mutations in SOD1 cause amyotrophic lateral sclerosis (ALS), an incurable motor neuron disease. The pathogenesis of the disease is poorly understood, but intracellular copper dyshomeostasis has been implicated as a key process in the disease. We recently observed that metallothioneins (MTs) are an excellent target for the modification of copper dyshomeostasis in a mouse model of ALS (SOD1(G93A)). Here, we offer a therapeutic strategy designed to increase the level of endogenous MTs. The upregulation of endogenous MTs by dexamethasone, a synthetic glucocorticoid, significantly improved the disease course and rescued motor neurons in SOD1(G93A) mice, even if the induction was initiated when peak body weight had decreased by 10%. Neuroprotection was associated with the normalization of copper dyshomeostasis, as well as with decreased levels of SOD1(G93A) aggregates. Importantly, these benefits were clearly mediated in a MT-dependent manner, as dexamethasone did not provide any protection when endogenous MTs were abolished from SOD1(G93A) mice. In conclusion, the upregulation of endogenous MTs represents a promising strategy for the treatment of ALS linked to mutant SOD1.

Sediment oxygen demand in eastern Kansas streams, 2014 and 2015

USGS Publications Warehouse

Foster, Guy M.; King, Lindsey R.; Graham, Jennifer L.

2016-08-29

Dissolved oxygen concentrations in streams are affected by physical, chemical, and biological factors in the water column and streambed, and are an important factor for the survival of aquatic organisms. Sediment oxygen demand (SOD) rates in Kansas streams are not well understood. During 2014 and 2015, the U.S. Geological Survey, in cooperation with the Kansas Department of Health and Environment, measured SOD at eight stream sites in eastern Kansas to quantify SOD rates and variability with respect to season, land use, and bottom-sediment characteristics. Sediment oxygen demand rates (SODT) ranged from 0.01 to 3.15 grams per square meter per day at the ambient temperature of the measurements. The summer mean SOD rate was 3.0-times larger than the late fall mean rate, likely because of increased biological activity at warm water temperatures. Given the substantial amount of variability in SOD rates possible within sites, heterogeneity of substrate type is an important consideration when designing SOD studies and interpreting the results. Sediment oxygen demand in eastern Kansas streams was correlated with land use and streambed-sediment characteristics, though the strength of relations varied seasonally. The small number of study sites precluded a more detailed analysis. The effect of basin land use and streambed sediment characteristics on SOD is currently (2016) not well understood, and there may be many contributing factors including basin influences on water quality that affect biogeochemical cycles and the biological communities supported by the stream.

Differential expression of copper-zinc superoxide dismutase gene of Polygonum sibiricum leaves, stems and underground stems, subjected to high-salt stress.

PubMed

Qu, Chun-Pu; Xu, Zhi-Ru; Liu, Guan-Jun; Liu, Chun; Li, Yang; Wei, Zhi-Gang; Liu, Gui-Feng

2010-01-01

In aerobic organisms, protection against oxidative damage involves the combined action of highly specialized antioxidant enzymes, such as copper-zinc superoxide dismutase. In this work, a cDNA clone which encodes a copper-zinc superoxide dismutase gene, named PS-CuZnSOD, has been identified from P. sibiricum Laxm. by the rapid amplification of cDNA ends method (RACE). Analysis of the nucleotide sequence reveals that the PS-CuZnSOD gene cDNA clone consists of 669 bp, containing 87 bp in the 5' untranslated region; 459 bp in the open reading frame (ORF) encoding 152 amino acids; and 123 bp in 3' untranslated region. The gene accession nucleotide sequence number in GenBank is GQ472846. Sequence analysis indicates that the protein, like most plant superoxide dismutases (SOD), includes two conserved ecCuZnSOD signatures that are from the amino acids 43 to 51, and from the amino acids 137 to 148, and it has a signal peptide extension in the front of the N-terminus (1-16 aa). Expression analysis by real-time quantitative PCR reveals that the PS-CuZnSOD gene is expressed in leaves, stems and underground stems. PS-CuZnSOD gene expression can be induced by 3% NaHCO(3). The different mRNA levels' expression of PS-CuZnSOD show the gene's different expression modes in leaves, stems and underground stems under the salinity-alkalinity stress.

RNA interference-mediated silencing of mutant superoxide dismutase rescues cyclosporin A-induced death in cultured neuroblastoma cells

PubMed Central

Maxwell, Michele M.; Pasinelli, Piera; Kazantsev, Aleksey G.; Brown, Robert H.

2004-01-01

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disorder resulting from selective death of motor neurons in the brain and spinal cord. In ≈25% of familial ALS cases, the disease is caused by dominantly acting point mutations in the gene encoding cytosolic Cu,Zn superoxide dismutase (SOD1). In cell culture and in rodent models of ALS, mutant SOD1 proteins exhibit dose-dependent toxicity; thus, agents that reduce mutant protein expression would be powerful therapeutic tools. A wealth of recent evidence has demonstrated that the mechanism of RNA-mediated interference (RNAi) can be exploited to achieve potent and specific gene silencing in vitro and in vivo. We have evaluated the utility of RNAi for selective silencing of mutant SOD1 expression in cultured cells and have identified small interfering RNAs capable of specifically inhibiting expression of ALS-linked mutant, but not wild-type, SOD1. We have investigated the functional effects of RNAi-mediated silencing of mutant SOD1 in cultured murine neuroblastoma cells. In this model, stable expression of mutant, but not wild-type, human SOD1 sensitizes cells to cytotoxic stimuli. We find that silencing of mutant SOD1 protects these cells against cyclosporin A-induced cell death. These results demonstrate a positive physiological effect caused by RNAi-mediated silencing of a dominant disease allele. The present study further supports the therapeutic potential of RNAi-based methods for the treatment of inherited human diseases, including ALS. PMID:14981234

The effects of different levels of superoxide dismutase in Modena on boar semen quality during liquid preservation at 17°C.

PubMed

Zhang, Xiao-Gang; Li, Hao; Wang, Le; Hao, Yang-Yi; Liang, Guo-Dong; Ma, Yun-Hui; Yang, Gong-She; Hu, Jian-Hong

2017-01-01

This study was conducted to investigate the influence of superoxide dismutase (SOD) on the quality of boar semen during liquid preservation at 17°C. Semen samples from 10 Duroc boars were collected and pooled, divided into five equal parts and diluted with Modena containing different concentrations (0, 100, 200, 300 and 400 U/mL) of SOD. During the process of liquid preservation at 17°C, sperm motility, acrosome integrity, membrane integrity, total antioxidant capacity (T-AOC) activity, malondialdehyde (MDA) content and hydrogen peroxide (H 2 O 2 ) content were measured and analyzed every 24 h. Meanwhile, effective survival time of boar semen during preservation was evaluated and analyzed. The results indicated that different concentrations of SOD in Modena showed different protective effects on boar sperm quality. Modena supplemented with SOD decreased the effects on reactive oxygen species on boar sperm quality during liquid preservation compared with that of the control group. The added 200 U/mL SOD group showed higher sperm motility, membrane integrity, acrosome integrity, effective survival time and T-AOC activity. Meanwhile, the added 200 U/mL SOD group showed lower MDA content and H 2 O 2 content. In conclusion, addition of SOD to Modena improved the boar sperm quality by reducing oxidative stress during liquid preservation at 17°C and the optimum concentration was 200 U/mL. © 2016 Japanese Society of Animal Science.

Manganese Superoxide Dismutase Gene-Modified Mesenchymal Stem Cells Attenuate Acute Radiation-Induced Lung Injury.

PubMed

Chen, Hai-Xu; Xiang, Hang; Xu, Wen-Huan; Li, Ming; Yuan, Jie; Liu, Juan; Sun, Wan-Jun; Zhang, Rong; Li, Jun; Ren, Zhao-Qi; Zhang, Xiao-Mei; Du, Bin; Wan, Jun; Wu, Ben-Yan; Zeng, Qiang; He, Kun-Lun; Yang, Chao

2017-06-01

Radiation-induced lung injury (RILI) is a major clinical complication for radiotherapy in thoracic tumors. An immediate effect of lung irradiation is the generation of reactive oxygen that can produce oxidative damage to DNA, lipids, and proteins resulting in lung cell injury or death. Currently, the medical management of RILI remains supportive. Therefore, there is an urgent need for the development of countermeasures. The present study aimed to evaluate the protective effect of manganese superoxide dismutase (MnSOD) gene-modified mesenchymal stem cells (MSCs) to facilitate the improved recovery of RILI. Here, nonobese diabetic/severe combined immunodeficiency mice received a 13 Gy dose of whole-thorax irradiation, and were then transfused intravenously with MnSOD-MSCs and monitored for 30 days. Lung histopathologic analysis, plasma levels of inflammatory cytokines (interleukin [IL]-1, IL-6, IL-10, and tumor necrosis factor-α), profibrotic factor transforming growth factor-β1, and the oxidative stress factor (hydroxyproline) were evaluated after MnSOD-MSC transplant. Apoptotic rates were evaluated by terminal deoxynucleotidyl transferase-mediated nick-end labeling immunohistochemical method. Colonization and differentiation of MnSOD-MSCs in the irradiated lung were analyzed by immunofluorescence staining. Consequently, systemic administration of MnSOD-MSCs significantly attenuated lung inflammation, ameliorated lung damage, and protected the lung cells from apoptosis. MnSOD-MSCs could differentiate into epithelial-like cells in vivo. MnSOD-MSCs were effective in modulating RILI in mice and had great potential for accelerating from bench to bedside.

Low-dose γ-radiation-induced oxidative stress response in mouse brain and gut: regulation by NFκB-MnSOD cross-signaling.

PubMed

Veeraraghavan, Jamunarani; Natarajan, Mohan; Herman, Terence S; Aravindan, Natarajan

2011-01-10

Radiation-induced amplification of reactive oxygen species (ROS) may be a sensing mechanism for activation of signaling cascades that influence cell fate. However, the regulated intrinsic mechanisms and targets of low-dose ionizing radiation (LDIR) are still unclear. Accordingly, we investigated the effects of LDIR on NFκB signal transduction and manganese superoxide dismutase (SOD2) activity in mice brain and gut. LDIR resulted in both dose-dependent and persistent NFκB activation in gut and brain. QPCR displayed a dose- and tissue-dependent differential modulation of 88 signaling molecules. With stringent criteria, a total of 15 (2cGy), 43 (10cGy) and 19 (50cGy) genes were found to be commonly upregulated between brain and gut. SOD2 immunostaining showed a LDIR-dose dependent increase. Consistent with the NFκB results, we observed a persistent increase in SOD2 activity after LDIR. Moreover, muting of LDIR-induced NFκB attenuated SOD2 transactivation and cellular localization. These results imply that exposure of healthy tissues to LDIR results in induced NFκB and SOD2 activity and transcriptional activation of NFκB-signal transduction/target molecules. More importantly, the results suggest that NFκB initiates a feedback response through transcriptional activation of SOD2 that may play a key role in the LDIR-induced oxidative stress response and may control the switch that directs cell fate. 2010 Elsevier B.V. All rights reserved.

Cu,Zn superoxide dismutase structure from a microbial pathogen establishes a class with a conserved dimer interface.

PubMed

Forest, K T; Langford, P R; Kroll, J S; Getzoff, E D

2000-02-11

Macrophages and neutrophils protect animals from microbial infection in part by issuing a burst of toxic superoxide radicals when challenged. To counteract this onslaught, many Gram-negative bacterial pathogens possess periplasmic Cu,Zn superoxide dismutases (SODs), which act on superoxide to yield molecular oxygen and hydrogen peroxide. We have solved the X-ray crystal structure of the Cu,Zn SOD from Actinobacillus pleuropneumoniae, a major porcine pathogen, by molecular replacement at 1.9 A resolution. The structure reveals that the dimeric bacterial enzymes form a structurally homologous class defined by a water-mediated dimer interface, and share with all Cu,Zn SODs the Greek-key beta-barrel subunit fold with copper and zinc ions located at the base of a deep loop-enclosed active-site channel. Our structure-based sequence alignment of the bacterial enzymes explains the monomeric nature of at least two of these, and suggests that there may be at least one additional structural class for the bacterial SODs. Two metal-mediated crystal contacts yielded our C222(1) crystals, and the geometry of these sites could be engineered into proteins recalcitrant to crystallization in their native form. This work highlights structural differences between eukaryotic and prokaryotic Cu,Zn SODs, as well as similarities and differences among prokaryotic SODs, and lays the groundwork for development of antimicrobial drugs that specifically target periplasmic Cu,Zn SODs of bacterial pathogens. Copyright 12000 Academic Press.

Systemic Operational Design: An Alternative to Estimate Planning

DTIC Science & Technology

2009-05-04

relationships found in the COE. Framing and campaign design, with emphasis on systems theory , have therefore made their way to the forefront of doctrinal...short explanation of the systems theory behind SOD, examines how the SOD process happens, and compares SOD with the time proven “Commander’s Estimate... Theory , Campaign planning, Contemporary Operating Environment, Commander’s Estimate Process, Operational design 16. SECURITY CLASSIFICATION OF

Decline of Hesperia ottoe (Lepidoptera: Hesperiidae) in Northern Tallgrass Prairie Preserves.

PubMed

Swengel, Ann B; Swengel, Scott R

2013-11-20

We counted butterflies on transect surveys during Hesperia ottoe flight period in 1988-2011 at tallgrass prairie preserves in four states (Illinois, Iowa, Minnesota, Wisconsin), divided into units cross-referenced to vegetation type and management history. H. ottoe occurred only in dry and sand prairie types, and was significantly more abundant in undegraded than semi-degraded prairie, and in discontinuous sod (with numerous unvegetated areas due to bare sand and/or rock outcrops) than in continuous sod. This skipper was significantly more abundant in small sites compared to medium and large sites, even when the analysis was limited to undegraded prairie analyzed separately by sod type. H. ottoe was significantly under-represented in year-burn 0 (the first growing season after fire) compared to an expected distribution proportional to survey effort. However, H. ottoe was also over-represented in fire-managed units compared to non-fire-managed units. However, by far most units and sites were in fire management and most populations declined to subdetection during this study. Peak abundance post-fire occurred in a later year-burn in discontinuous sod and was much higher than in continuous sod. We also analyze H. ottoe status and trend in midwestern prairie preserves by compiling a dataset of our and others' butterfly surveys from 1974 to 2011. Only 1/9 sites with continuous sod had detectable H. ottoe in recent year(s). In discontinuous sod, 2/6 did, with two sites lacking data for the last few years. The number of years H. ottoe was still detectable after preservation and the number of years to consistent non-detection were both significantly higher in discontinuous than continuous sod. Both measures of population persistence averaged over twice as long in discontinuous than continuous sod, and correlated negatively with prairie size. The year when consistent non-detection began varied over several decades among sites. Despite the currently urgent need to identify how to manage preserves successfully for H. ottoe, such research now needs to be very cautious, because of the extreme fragility of the few remaining populations and the ruggedness of the preserves where H. ottoe is still known to occur.

Knocking down metabotropic glutamate receptor 1 improves survival and disease progression in the SOD1(G93A) mouse model of amyotrophic lateral sclerosis.

PubMed

Milanese, Marco; Giribaldi, Francesco; Melone, Marcello; Bonifacino, Tiziana; Musante, Ilaria; Carminati, Enrico; Rossi, Pia I A; Vergani, Laura; Voci, Adriana; Conti, Fiorenzo; Puliti, Aldamaria; Bonanno, Giambattista

2014-04-01

Amyotrophic lateral sclerosis (ALS) is a late-onset fatal neurodegenerative disease reflecting degeneration of upper and lower motoneurons (MNs). The cause of ALS and the mechanisms of neuronal death are still largely obscure, thus impairing the establishment of efficacious therapies. Glutamate (Glu)-mediated excitotoxicity plays a major role in MN degeneration in ALS. We recently demonstrated that the activation of Group I metabotropic Glu autoreceptors, belonging to both type 1 and type 5 receptors (mGluR1 and mGluR5), at glutamatergic spinal cord nerve terminals, produces excessive Glu release in mice over-expressing human superoxide-dismutase carrying the G93A point mutation (SOD1(G93A)), a widely used animal model of human ALS. To establish whether these receptors are implicated in ALS, we generated mice expressing half dosage of mGluR1 in the SOD1(G93A) background (SOD1(G93A)Grm1(crv4/+)), by crossing the SOD1(G93A) mutant mouse with the Grm1(crv4/+) mouse, lacking mGluR1 because of a spontaneous recessive mutation. SOD1(G93A)Grm1(crv4/+) mice showed prolonged survival probability, delayed pathology onset, slower disease progression and improved motor performances compared to SOD1(G93A) mice. These effects were associated to reduction of mGluR5 expression, enhanced number of MNs, decreased astrocyte and microglia activation, normalization of metallothionein and catalase mRNA expression, reduced mitochondrial damage, and decrease of abnormal Glu release in spinal cord of SOD1(G93A)Grm1(crv4/+)compared to SOD1(G93A) mice. These results demonstrate that a lower constitutive level of mGluR1 has a significant positive impact on mice with experimental ALS, thus providing the rationale for future pharmacological approaches to ALS by selectively blocking Group I metabotropic Glu receptors. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Effect of high dietary zinc on plasma ceruloplasmin and erythrocyte superoxide dismutase activities in copper-depleted and repleted rats.

PubMed

Panemangalore, M; Bebe, F N

1996-01-01

The effect of moderately high dietary zinc (Zn) on the activities of plasma (PL) ceruloplasmin (CP), and PL and erythrocyte (RBC) copper (Cu), Zn superoxide dismutase (SOD) was determined in weanling rats fed Cu-deficient (DEF; < 1 mg Cu/kg), marginal (MAR; 2 mg Cu/kg), or control (CON; 5 mg Cu/kg) copper diets containing normal or high Zn (HZn; 60 mg/kg) for 4 wk and supplemented with oral Cu (CuS; 5 mg/L) in drinking water for 0, 1, 3, or 7 d. PL Cu decreased (67% compared to CON; p < or = 0.05) in the DEF and increased to control level after 3 d of CuS; increased in the MAR group after 1 d of CuS. HZn reduced overall PL Cu by 27% in all groups, but did not alter the linear increase in PL Cu between 0 and 3 d of Cu S. PL CP activity altered concomitantly with PL Cu levels: The time course of increase in CP activity after 0-3 d of CuS was not influenced by HZn in the diet and CP declined in the DEF group by 92%. There was no correlation between dietary Cu level and PL CP. PL SOD activity decreased by 46% (p < or = .05) in the DEF group, increased to control activity after 1 d of CuS and declined slightly after 7 d; MAR diet did not alter PL SOD. HZn diet increased PL SOD activity in all groups by 150%, reduced activity in the DEF and MAR groups by 65 and 37% and delayed the recovery of PL SOD after CuS. RBC SOD declined in the DEF and MAR groups by 56 and 33% (p < or = 0.05) and did not respond to CuS; HZn diet did not influence RBC SOD activity. These data indicate that moderately high Zn in the diet reduces PL Cu, but not PL CP activity or the recovery of PL Cu or CP activity after oral CuS of Cu-deficient rats, modifies the response of PL SOD to dietary Cu, but does not influence RBC SOD activity.

The effect of nano-TiO2 photocatalysis on the antioxidant activities of Cu, Zn-SOD at physiological pH.

PubMed

Zheng, Wen; Zou, Hai-Feng; Lv, Shao-Wu; Lin, Yan-Hong; Wang, Min; Yan, Fei; Sheng, Ye; Song, Yan-Hua; Chen, Jie; Zheng, Ke-Yan

2017-09-01

Security issues of nanoparticles on biological toxicity and potential environmental risk have attracted more and more attention with the rapid development and wide applications of nanotechnology. In this work, we explored the effect and probable mechanism of nano-TiO 2 on antioxidant activity of copper, zinc superoxide dismutase (Cu, Zn-SOD) under natural light and mixed light at physiological pH. Nano-TiO 2 was prepared by sol-hydrothermal method, and then characterized by X-ray Diffraction (XRD) and Transmission electron micrographs (TEM). The Cu, Zn-SOD was purified by sephadex G75 chromatography and qualitatively analyzed by sodium dodecyl sulfate polypropylene amide gel electrophoresis (SDS-PAGE). The effect and mechanism were elucidated base on Fourier Transform Infrared Spectrometer (FT-IR), Circular Dichroism (CD), zeta potential, and electron spin resonance (ESR) methods. Accompanying the results of FT-IR, CD and zeta potential, it could be concluded that nano-TiO 2 had no effect on the antioxidant activity of Cu, Zn-SOD by comparing the relative activity under natural light at physiological pH. But the relative activity of Cu, Zn-SOD significantly decreased along with the increase of nano-TiO 2 concentration under the mixed light. The results of ESR showed the cause of this phenomenon was the Cu(II) in the active site of Cu, Zn-SOD was reduced to Cu(I) by H 2 O 2 and decreased the content of active Cu, Zn-SOD. The reduction can be inhibited by catalase. Excess O 2 ·- produced by nano-TiO 2 photocatalysis under mixed light accumulated a mass of H 2 O 2 through disproportionation reaction in this experimental condition. The results show that nano-TiO 2 cannot affect the antioxidant activity of Cu, Zn-SOD in daily life. The study on the effect of nano-TiO 2 on Cu, Zn-SOD will provide a valid theory support for biological safety and the toxicological effect mechanism of nanomaterials on enzyme. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of macromolecular crowding on the structure of the protein complex superoxide dismutase

NASA Astrophysics Data System (ADS)

Rajapaksha Mudalige, Ajith Rathnaweera

Biological environments contain between 7 - 40% macromolecules by volume. This reduces the available volume for macromolecules and elevates the osmotic pressure relative to pure water. Consequently, biological macromolecules in their native environments tend to adopt more compact and dehydrated conformations than those in vitro. This effect is referred to as macromolecular crowding and constitutes an important physical difference between native biological environments and the simple solutions in which biomolecules are usually studied. We used small angle scattering (SAS) to measure the effects of macromolecular crowding on the size of a protein complex, superoxide dismutase (SOD). Crowding was induced using 400 MW polyethylene glycol (PEG), triethylene glycol (TEG), methyl-alpha-glucoside (alpha-MG) and trimethylamine N-oxide (TMAO). Parallel small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) allowed us to unambiguously attribute apparent changes in radius of gyration to changes in the structure of SOD. For a 40% PEG solution, we find that the volume of SOD was reduced by 9%. SAS coupled with osmotic pressure measurements allowed us to estimate a compressibility modulus for SOD. We believe this to be the first time the osmotic compressibility of a protein complex was measured. Molecular Dynamics (MD) simulations are widely used to obtain insights on biomolecular processes. However, it is not clear whether MD is capable of predicting subtle effects of macromolecular crowding. We used our experimentally observed compressibility of SOD to evaluate the ability of MD to predict macromolecular crowding. Effects of macromolecular crowding due to PEG on SOD were modeled using an all atom MD simulation with the CHARMM forcefield and the crystallographically resolved structures of SOD and PEG. Two parallel MD simulations were performed for SOD in water and SOD in 40% PEG for over 150~ns. Over the period of the simulation the SOD structure in 40% PEG did not change compared to the SOD structure in water. It therefore appears that under the conditions of our simulations MD could not describe the experimentally observed effects of macromolecular crowding. In a separate project, we measured the rate of diffusive transport in excised porcine corneal stroma using FCS for fluorescent labeled dextran molecules with hydrodynamic radii ranging from 1.3 to 34 nm. Dextran molecules diffuse more slowly in cornea as compared to buffer solution. The reduction in diffusion coefficient is modest however (67% smaller), and is uniform over the range of sizes that we measured. Diffusion coefficients measured parallel vs. perpendicular to the collagen lamellae were indistinguishable. This indicates that diffusion in the corneal stroma is not highly anisotropic. Delivery of therapeutic agents to the eye requires efficient transport through cellular and extracellular barriers. Our measurements bring important insights into how macromolecular and nanoparticle therapeutics might permeate through the eyes.

miR-140-5p regulates hypoxia-mediated human pulmonary artery smooth muscle cell proliferation, apoptosis and differentiation by targeting Dnmt1 and promoting SOD2 expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yanwei; Xu, Jing, E-mail: xujingdoc@163.com

miR-140-5p is down-regulated in patients with pulmonary arterial hypertension (PAH) and experimental models of PAH, and inhibits hypoxia-mediated pulmonary artery smooth muscle cell (PASMC) proliferation in vitro. Delivery of synthetic miR-140-5p prevents and treats established, experimental PAH. DNA methyltransferase 1 (Dnmt1) is up-regulated in PAH associated human PASMCs (HPASMCs), which promotes the development of PAH by hypermethylation of CpG islands within the promoter for superoxide dismutase 2 (SOD2) and down-regulating SOD2 expression. We searched for miR-140-5p targets using TargetScan, PicTar and MiRanda tools, and found that Dnmt1 is a potential target of miR-140-5p. Based on these findings, we speculated that miR-140-5pmore » might target Dnmt1 and regulate SOD2 expression to regulate hypoxia-mediated HPASMC proliferation, apoptosis and differentiation. We detected the expression of miR-140-5p, Dnmt1 and SOD2 by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays, respectively, and found down-regulation of miR-140-5p and SOD2 and up-regulation of Dnmt1 exist in PAH tissues and hypoxia-mediated HPASMCs. Cell proliferation, apoptosis and differentiation detection showed that miR-140-5p inhibits proliferation and promotes apoptosis and differentiation of HPASMCs in hypoxia, while the effect of Dnmt1 on hypoxia-mediated HPASMCs is reversed. Luciferase assay confirmed that miR-140-5p targets Dnmt1 directly. An inverse correlation is also found between miR-140-5p and Dnmt1 in HPASMCs. In addition, we further investigated whether miR-140-5p and Dnmt1 regulate HPASMC proliferation, apoptosis and differentiation by regulating SOD2 expression, and the results confirmed our speculation. Taken together, these results indicated that miR-140-5p at least partly targets Dnmt1 and regulates SOD2 expression to inhibit proliferation and promote apoptosis and differentiation of HPASMCs in hypoxia. - Highlights: • miR-140-5p and SOD2 are down-regulated in PAH tissues and hypoxia-mediated HPASMCs. • Dnmt1 is up-regulated in PAH tissues and hypoxia-mediated HPASMCs. • miR-140-5p regulates HPASMC proliferation, apoptosis and differentiation. • Dnmt1 and SOD2 regulates HPASMC proliferation, apoptosis and differentiation. • miR-140-5p targets Dnmt1 and regulates SOD2 expression.« less

An ALS-Associated Mutant SOD1 Rapidly Suppresses KCNT1 (Slack) Na+-Activated K+ Channels in Aplysia Neurons.

PubMed

Zhang, Yalan; Ni, Weiming; Horwich, Arthur L; Kaczmarek, Leonard K

2017-02-22

Mutations that alter levels of Slack (KCNT1) Na + -activated K + current produce devastating effects on neuronal development and neuronal function. We now find that Slack currents are rapidly suppressed by oligomers of mutant human Cu/Zn superoxide dismutase 1 (SOD1), which are associated with motor neuron toxicity in an inherited form of amyotrophic lateral sclerosis (ALS). We recorded from bag cell neurons of Aplysia californica , a model system to study neuronal excitability. We found that injection of fluorescent wild-type SOD1 (wt SOD1YFP) or monomeric mutant G85R SOD1YFP had no effect on net ionic currents measured under voltage clamp. In contrast, outward potassium currents were significantly reduced by microinjection of mutant G85R SOD1YFP that had been preincubated at 37°C or of cross-linked dimers of G85R SOD1YFP. Reduction of potassium current was also seen with multimeric G85R SOD1YFP of ∼300 kDa or >300 kDa that had been cross-linked. In current clamp recordings, microinjection of cross-linked 300 kDa increased excitability by depolarizing the resting membrane potential, and decreasing the latency of action potentials triggered by depolarization. The effect of cross-linked 300 kDa on potassium current was reduced by removing Na + from the bath solution, or by knocking down levels of Slack using siRNA. It was also prevented by pharmacological inhibition of ASK1 (apoptosis signal-regulating kinase 1) or of c-Jun N-terminal kinase, but not by an inhibitor of p38 mitogen-activated protein kinase. These results suggest that soluble mutant SOD1 oligomers rapidly trigger a kinase pathway that regulates the activity of Na + -activated K + channels in neurons. SIGNIFICANCE STATEMENT Slack Na + -activated K + channels (KCNT1, K Na 1.1) regulate neuronal excitability but are also linked to cytoplasmic signaling pathways that control neuronal protein translation. Mutations that alter the amplitude of these currents have devastating effects on neuronal development and function. We find that injection of oligomers of mutant superoxide dismutase 1 (SOD1) into the cytoplasm of invertebrate neurons rapidly suppresses these Na + -activated K + currents and that this effect is mediated by a MAP kinase cascade, including ASK1 and c-Jun N-terminal kinase. Because amyotrophic lateral sclerosis is a fatal adult-onset neurodegenerative disease produced by mutations in SOD1 that cause the enzyme to form toxic oligomers, our findings suggest that suppression of Slack channels may be an early step in the progression of the disease. Copyright © 2017 the authors 0270-6474/17/372258-08$15.00/0.

Effects of Aluminum Stress on Protective Enzyme Activity in Tie Guanyin leaves

NASA Astrophysics Data System (ADS)

Sun, JingWei; Du, NaiChen; Zhang, YunFeng

2018-01-01

The experiment was adopted to study the change of SOD, CAT and POD activity of Tie guanyin (new leaf and old leaf blade of different concentrations of aluminum stress; in this paper, 0 (CK), 40, 200, four gradients of 400mg/L concentration of Al3+ in acidic conditions, Tieguanyin tea leaf SOD, cat and POD activity changes. The results showed that high concentrations of aluminum stress on antioxidant enzyme system activity cannot continue to increase; at the same time showed that SOD is sensitive to aluminum toxicity concentration change, its sensitivity is higher than CAT and POD, SOD and CAT activity and the aging and decline of plant There was a positive correlation.

Protection against hyperoxia by serum from endotoxin treated rats: absence of superoxide dismutase induction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berg, J.T.; Smith, R.M.

Endotoxin greatly reduces lung injury and pleural effusions in adult rats exposed to normobaric hyperoxia (> 98% oxygen for 60 hours). This study reports that serum from endotoxin treated donor rats protects serum recipients against hyperoxic lung injury without altering lung superoxide dismutase (SOD) activity. Rats pretreated with endotoxin alone were protected and exhibited an increase in lung SOD activity as previously reported by others. Protection by serum was not due to the transfer of residual endotoxin or SOD. These results show, that protection from oxygen toxicity can occur in rats without an increase in lung SOD and suggest thatmore » a serum factor may be involved.« less

Cu,Zn-superoxide dismutase is lower and copper chaperone CCS is higher in erythrocytes of copper-deficient rats and mice.

PubMed

West, Elizabeth C; Prohaska, Joseph R

2004-09-01

Discovery of a sensitive blood biochemical marker of copper status would be valuable for assessing marginal copper intakes. Rodent models were used to investigate whether erythrocyte concentrations of copper,zinc-superoxide dismutase (SOD), and the copper metallochaperone for SOD (CCS) were sensitive to dietary copper changes. Several models of copper deficiency were studied in postweanling male Holtzman rats, male Swiss Webster mice offspring, and both rat and mouse dams. Treatment resulted in variable but significantly altered copper status as evaluated by the presence of anemia, and lower liver copper and higher liver iron concentrations in copper-deficient compared with copper-adequate animals. Associated with this copper deficiency were consistent reductions in immunoreactive SOD and robust enhancements in CCS. In most cases, the ratio of CCS:SOD was several-fold higher in red blood cell extracts from copper-deficient compared with copper-adequate rodents. Determination of red cell CCS:SOD may be useful for assessing copper status of humans.

Properties of slow- and fast-twitch muscle fibres in a mouse model of amyotrophic lateral sclerosis.

PubMed

Atkin, Julie D; Scott, Rachel L; West, Jan M; Lopes, Elizabeth; Quah, Alvin K J; Cheema, Surindar S

2005-05-01

This investigation was undertaken to determine if there are altered histological, pathological and contractile properties in presymptomatic or endstage diseased muscle fibres from representative slow-twitch and fast-twitch muscles of SOD1 G93A mice in comparison to wildtype mice. In presymptomatic SOD1 G93A mice, there was no detectable peripheral dysfunction, providing evidence that muscle pathology is secondary to motor neuronal dysfunction. At disease endstage however, single muscle fibre contractile analysis demonstrated that fast-twitch muscle fibres and neuromuscular junctions are preferentially affected by amyotrophic lateral sclerosis-induced denervation, being unable to produce the same levels of force when activated by calcium as muscle fibres from their age-matched controls. The levels of transgenic SOD1 expression, aggregation state and activity were also examined in these muscles but there no was no preference for muscle fibre type. Hence, there is no simple correlation between SOD1 protein expression/activity, and muscle fibre type vulnerability in SOD1 G93A mice.

Purification of Cu/Zn superoxide dismutase from Piper betle leaf and its characterization in the oral cavity.

PubMed

Liu, Yu-Ching; Lee, Miau-Rong; Chen, Chao-Jung; Lin, Yung-Chang; Ho, Heng-Chien

2015-03-04

The aim of this study was to purify protein(s) from Piper betle leaf for identification and further characterization. A functionally unknown protein was purified to apparent homogeneity with a molecular mass of 15.7 kDa and identified as Cu/Zn superoxide dismutase (SOD). The purified SOD appeared to be monomeric and converted to its dimeric form with increased enzymatic activity in betel nut oral extract. This irreversible conversion was mainly induced by slaked lime, resulting from the increase in pH of the oral cavity. Oral extract from chewing areca nut alone also induced SOD dimerization due to the presence of arginine. The enhanced activity of the SOD dimer was responsible for the continuous production of hydrogen peroxide in the oral cavity. Thus, SOD may contribute to oral carcinogenesis through the continuous formation of hydrogen peroxide in the oral cavity, in spite of its protective role against cancer in vivo.

Activity of superoxide dismutase in Galleria mellonella larvae infected with entomopathogenic nematodes Steinernema affinis and S. feltiae.

PubMed

Zółtowska, Krystyna; Grochla, Paulina; Łopieńska-Biernat, Elzbieta

2006-01-01

The influence of infection with two species of entomopathogenic nematodes of Steinernematidae family on the activity of superoxide dismutase (SOD) of the host was studied. Last instar larvae of Galleria mellonella were experimentally infected with Steinernema affinis and S. feltiae at 20 invasive juveniles per insect. At 6, 12, 18, 24 and 36 h after infection activity of SOD was determined in extracts from infected and control insects. The activity of SOD decreased gradually in the controls during the experiment. The activity of enzyme was 2-4-times higher in insects from both infected groups than in the control. During the first 12 h of infection the activity of SOD in insects infected with S. feltiae was higher than in those infected with S. affinis, then the activity of enzyme in the insects of both infected groups stayed at a similar level. A significant decrease of SOD activity in infected was recorded in second day of the infection.

Rosmarinic acid and antioxidant enzyme activities in Lavandula vera MM cell suspension culture: a comparative study.

PubMed

Georgiev, Milen; Abrashev, Radoslav; Krumova, Ekaterina; Demirevska, Klimentina; Ilieva, Mladenka; Angelova, Maria

2009-11-01

The growth and intracellular protein content of lavender (Lavandula vera MM) cell suspension culture was followed along with some antioxidant defense system members-non-enzymatic (rosmarinic acid) and enzymatic [superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6)]. It was found that the media content and the cultivation mode strongly influenced the production of plant defense compounds as well as the ratio between non-enzymatic and enzymatic ones. The bioreactor culture contains about two times more rosmarinic acid, superoxide dismutase, and catalase compared to the shake-flask cultivation. These findings are discussed with respect to the relative stress levels and plant antioxidant orchestra system. It was concluded that investigated defense system components (enzymatic and non-enzymatic) were closely associated in a complex balance. The three isoenzyme forms of SOD (Cu/ZnSOD, FeSOD, and MnSOD) in the cells of Lavandula vera were revealed by polyacrylamide gel electrophoresis analysis, and the FeSOD isoform exhibited highest activity.

Efficient intradermal delivery of superoxide dismutase using a combination of liposomes and iontophoresis for protection against UV-induced skin damage.

PubMed

Kigasawa, Kaoru; Miyashita, Moeko; Kajimoto, Kazuaki; Kanamura, Kiyoshi; Harashima, Hideyoshi; Kogure, Kentaro

2012-01-01

Superoxide dismutase (SOD) is a potent antioxidant agent that protects against UV-induced skin damage. However, its high molecular weight is a significant obstacle for efficient delivery into the skin through the stratum corneum and development of antioxidant activity. Recently, we developed a non-invasive transfollicular delivery system for macromolecules using a combination of liposomes and iontophoresis, that represents promising technology for enhancing transdermal administration of charged drugs (IJP, 403, 2011, Kajimoto et al.). In this study, in rats we attempted to apply this system to intradermal delivery of SOD for preventing UV-induced skin injury. SOD encapsulating in cationic liposomes was subjected to anodal iontophoresis. After iontophoretic treatment, the liposomes were diffused widely in the viable skin layer around hair follicles. In contrast, passive diffusion failed to transport liposomes efficiently into the skin. Iontophoretic delivery of liposomes encapsulating SOD caused a marked decrease in the production of oxidative products, such as malondialdehyde, hexanoyl lysine, and 8-hydroxi-2-deoxyguanosine, in UV-irradiated skin. These findings suggested that functional SOD can be delivered into the skin using a combination of iontophoresis and a liposomal system. In conclusion, we succeeded in developing an efficient intradermal SOD delivery system, that would be useful for delivery of other macromolecules.

Molecular mechanism of composite nanoparticles TiO2/WO3/GO-induced activity changes of catalase and superoxide dismutase.

PubMed

Hao, Xiaoyan; Zhang, Li; Zheng, Xin; Zong, Wansong; Liu, Chunguang

2018-06-21

More and more composite nano-photocatalysts were developed by doping, modifying and coupling, which expanded its application but resulted in pollution due to the unrecyclability. Composite photocatalyst TiO 2 /WO 3 /GO, as a model, was evaluated by exploring the molecular mechanism of TiO 2 /WO 3 /GO-induced activity changes of catalase (CAT) and superoxide dismutase (SOD). Results showed that TiO 2 /WO 3 /GO could lead to conformational and functional changes of CAT and SOD. The activity of both CAT and SOD increased depending on the exposure dose of TiO 2 /WO 3 /GO. The change skeleton structure and increase of α-helix content of CAT and SOD were certificated with UV-vis absorption and CD measurements. Intrinsic fluorescence of CAT and SOD were quenched by dynamic quenching. Micro-environment of amino acid residues of CAT and SOD became more hydrophilic, and the microenvironment of Trp residues was more vulnerable than Tyr residues with TiO 2 /WO 3 /GO exposure. In addition, inhibitory comparison between GO, TiO 2 , WO 3 and TiO 2 /WO 3 /GO was made, results showed that composite nano-photocatalyst exhibited different inhibitory compared to their parent nano-particles. Copyright © 2018. Published by Elsevier B.V.

The activity of superoxide dismutase in animal liver and erythrocyte at Sea Area nearby Dayawan Nuclear Power Station

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Ge; Cai, Yana; Chen, Huizhen

1995-11-01

Many tests, the effect of ionizing radiation on SOD in vivo and vitro, had proved that the irradiation can cause the SOD activity to decrease with the increase of irradiation dose, change some physicochemical properties and structure. This artical was to study the activity of SOD in Fish (Thearpon jorbua) and Toad(Bufo melanostictus) liver erythrocyte at sea area nearby Dayawan Nuclear Power Station (Nps). We found that the SOD activity in fish liver, after NPS revolved one year, was higher than that of before revoling (7.30 {plus_minus} 1.35U/mg protein, 5.49 {plus_minus}1.56 U/mg protein respectively). The SOD activity in the toadmore » liver at NPS revolving one year after was decreased (4.54 {plus_minus} 0.75 U/mg protein 5.68{plus_minus} 1.49U/mg protein P < 0.001) but in erythrocyte increased (2.32 {plus_minus} 0.75 U/mg Hb, 0.70 {plus_minus} 0.33 U/mg Hb P < 0.001). These results indicated that the SOD activity was changed in different with the animal variety. The effect of irradiation on fish at present was absent, on toad need to research in the future.« less

Manganese Superoxide Dismutase Gene Expression Is Induced by Nanog and Oct4, Essential Pluripotent Stem Cells' Transcription Factors.

PubMed

Solari, Claudia; Vázquez Echegaray, Camila; Cosentino, María Soledad; Petrone, María Victoria; Waisman, Ariel; Luzzani, Carlos; Francia, Marcos; Villodre, Emilly; Lenz, Guido; Miriuka, Santiago; Barañao, Lino; Guberman, Alejandra

2015-01-01

Pluripotent stem cells possess complex systems that protect them from oxidative stress and ensure genomic stability, vital for their role in development. Even though it has been reported that antioxidant activity diminishes along stem cell differentiation, little is known about the transcriptional regulation of the involved genes. The reported modulation of some of these genes led us to hypothesize that some of them could be regulated by the transcription factors critical for self-renewal and pluripotency in embryonic stem cells (ESCs) and in induced pluripotent stem cells (iPSCs). In this work, we studied the expression profile of multiple genes involved in antioxidant defense systems in both ESCs and iPSCs. We found that Manganese superoxide dismutase gene (Mn-Sod/Sod2) was repressed during diverse differentiation protocols showing an expression pattern similar to Nanog gene. Moreover, Sod2 promoter activity was induced by Oct4 and Nanog when we performed a transactivation assay using two different reporter constructions. Finally, we studied Sod2 gene regulation by modulating the expression of Oct4 and Nanog in ESCs by shRNAs and found that downregulation of any of them reduced Sod2 expression. Our results indicate that pluripotency transcription factors positively modulate Sod2 gene transcription.

Manganese Superoxide Dismutase Gene Expression Is Induced by Nanog and Oct4, Essential Pluripotent Stem Cells’ Transcription Factors

PubMed Central

Solari, Claudia; Vázquez Echegaray, Camila; Cosentino, María Soledad; Petrone, María Victoria; Waisman, Ariel; Luzzani, Carlos; Francia, Marcos; Villodre, Emilly; Lenz, Guido; Miriuka, Santiago; Barañao, Lino; Guberman, Alejandra

2015-01-01

Pluripotent stem cells possess complex systems that protect them from oxidative stress and ensure genomic stability, vital for their role in development. Even though it has been reported that antioxidant activity diminishes along stem cell differentiation, little is known about the transcriptional regulation of the involved genes. The reported modulation of some of these genes led us to hypothesize that some of them could be regulated by the transcription factors critical for self-renewal and pluripotency in embryonic stem cells (ESCs) and in induced pluripotent stem cells (iPSCs). In this work, we studied the expression profile of multiple genes involved in antioxidant defense systems in both ESCs and iPSCs. We found that Manganese superoxide dismutase gene (Mn-Sod/Sod2) was repressed during diverse differentiation protocols showing an expression pattern similar to Nanog gene. Moreover, Sod2 promoter activity was induced by Oct4 and Nanog when we performed a transactivation assay using two different reporter constructions. Finally, we studied Sod2 gene regulation by modulating the expression of Oct4 and Nanog in ESCs by shRNAs and found that downregulation of any of them reduced Sod2 expression. Our results indicate that pluripotency transcription factors positively modulate Sod2 gene transcription. PMID:26642061

Mice Deficient in Both Mn Superoxide Dismutase and Glutathione Peroxidase-1 Have Increased Oxidative Damage and a Greater Incidence of Pathology but No Reduction in Longevity

PubMed Central

Zhang, Yiqiang; Ikeno, Yuji; Qi, Wenbo; Chaudhuri, Asish; Li, Yan; Bokov, Alex; Thorpe, Suzanne R.; Baynes, John W.; Epstein, Charles; Richardson, Arlan

2009-01-01

To test the impact of increased mitochondrial oxidative stress as a mechanism underlying aging and age-related pathologies, we generated mice with a combined deficiency in two mitochondrial-localized antioxidant enzymes, Mn superoxide dismutase (MnSOD) and glutathione peroxidase-1 (Gpx-1). We compared life span, pathology, and oxidative damage in Gpx1−/−, Sod2+/−Gpx1+/−, Sod2+/−Gpx1−/−, and wild-type control mice. Oxidative damage was elevated in Sod2+/−Gpx1−/− mice, as shown by increased DNA oxidation in liver and skeletal muscle and increased protein oxidation in brain. Surprisingly, Sod2+/−Gpx1−/− mice showed no reduction in life span, despite increased levels of oxidative damage. Consistent with the important role for oxidative stress in tumorigenesis during aging, the incidence of neoplasms was significantly increased in the older Sod2+/−Gpx1−/− mice (28–30 months). Thus, these data do not support a significant role for increased oxidative stress as a result of compromised mitochondrial antioxidant defenses in modulating life span in mice and do not support the oxidative stress theory of aging. PMID:19776219

The effect of ILLLI on peripheral blood SOD, MDA in psoriasis treatment

NASA Astrophysics Data System (ADS)

Zhu, Jing; Nie, Fan

2005-07-01

Objective: To research the effect of Intravascular low level laser irradiation (ILLLI) on the SOD,MDA in the treatment of psoriasis. Method :47 patients suffering from psoriasis from five groups were treated by Intravascular low level laser irradiation (power:4-5mw,1h per day, period of treatment: 10 days) .We checked the change of SOD,MDA peripheral blood in 10 normal people between pre and post treatment. Group A were treated by He-Ne laser combined with drug, group B were treated by semi-conductor laser combined with drug, group C were treated only by He-Ne laser, group D were treated only by semiconductor laser, group E were treated only by drug . Results: The levels of SOD in red cell of psoriatic patients from five groups after treatment were significantly lower than that of controlled group. The levels of SOD of them were significantly increased and nearly closed to that of controlled group; the levels of MDA in red cell of psoriatic patients from five groups after treatment were significantly higher than that of controlled group; the levels of MDA of them are decreased ,however, they were still not recovered to normal levels. Conclusions: ILLLI, both He-Ne laser and semiconductor laser, can activate SOD in psoriasis patients and enhance their ability of anti-oxidation.

SOD1 Function and Its Implications for Amyotrophic Lateral Sclerosis Pathology: New and Renascent Themes.

PubMed

Bunton-Stasyshyn, Rosie K A; Saccon, Rachele A; Fratta, Pietro; Fisher, Elizabeth M C

2015-10-01

The canonical role of superoxide dismutase 1 (SOD1) is as an antioxidant enzyme protecting the cell from reactive oxygen species toxicity. SOD1 was also the first gene in which mutations were found to be causative for the neurodegenerative disease amyotrophic lateral sclerosis (ALS), more than 20 years ago. ALS is a relentless and incurable mid-life onset disease, which starts with a progressive paralysis and usually leads to death within 3 to 5 years of diagnosis; in the majority of cases, the intellect appears to remain intact while the motor system degenerates. It rapidly became clear that when mutated SOD1 takes on a toxic gain of function in ALS. However, this novel function remains unknown and many cellular systems have been implicated in disease. Now it seems that SOD1 may play a rather larger role in the cell than originally realized, including as a key modulator of glucose signaling (at least so far in yeast) and in RNA binding. Here, we consider some of the new findings for SOD1 in health and disease, which may shed light on how single amino acid changes at sites throughout this protein can cause devastating neurodegeneration in the mammalian motor system. © The Author(s) 2014.

Protective effect of Mn(III)-desferrioxamine B upon oxidative stress caused by ozone and acid rain in the Brazilian soybean cultivar Glycine max "Sambaiba".

PubMed

Esposito, Jéssica Bordotti Nobre; Esposito, Breno Pannia; Azevedo, Ricardo Antunes; Cruz, Luciano Soares; da Silva, Luzimar Campos; de Souza, Silvia Ribeiro

2015-04-01

This study aimed to investigate the effects of the Mn complex (Mn(III)-desferrioxamine B (MnDFB)) on oxidative stress in the Brazilian soybean cultivar Glycine max "Sambaiba" following exposure to ozone and acid rain. We determined the suitable dose of MnDFB to apply to G. max seedlings using a dose-response curve. The highest superoxide dismutase (SOD) activity and Mn content in leaves were found upon the application of 8 μM MnDFB. Thus, G. max seedlings pretreated with 8 μM MnDFB were individually exposed to ozone and acid rain simulated. Pretreatment with MnDFB reduced lipid peroxidation upon ozone exposure and increased SOD activity in leaves; it did not alter the metal content in any part of the plant. Conversely, following acid rain exposure, neither the metal content in leaves nor SOD enzyme activity were directly affected by MnDFB, unlike pH. Our findings demonstrated that exogenous MnDFB application before ozone exposure may modulate the MnSOD, Cu/ZnSOD, and FeSOD activities to combat the ROS excess in the cell. Here, we demonstrated that the applied dose of MnDFB enhances antioxidative defenses in soybean following exposure to acid rain and especially to ozone.

Superoxide Dismutase: A Predicting Factor for Boar Semen Characteristics for Short-Term Preservation

PubMed Central

Nemec Svete, Alenka

2014-01-01

Superoxide dismutase (SOD), total antioxidant capacity (TAC), and thiobarbituric acid reactive substances (TBARS) in seminal plasma were evaluated on the basis of receiver operating characteristics (ROC) analysis as predictors for distinguishing satisfactory from unsatisfactory boar semen samples after storage. SOD on day 0 correlated significantly with progressive motility (r = −0.686; P < 0.05) and viability (r = −0.513; P < 0.05) after storage; TBARS correlated only with motility (r = −0.480; P < 0.05). Semen samples that, after 3 days of storage, fulfilled all criteria for semen characteristics (viability > 85%, motility > 70%, progressive motility > 25%, and normal morphology > 50%) had significantly lower SOD levels on the day 0 than those with at least one criterion not fulfilled (P < 0.05) following storage. SOD levels of less than 1.05 U/mL predicted with 87.5% accuracy that fresh semen will suit the requirements for satisfactory semen characteristics after storage, while semen with SOD levels higher than 1.05 U/mL will not fulfill with 100% accuracy at least one semen characteristic after storage. These results support the proposal that SOD in fresh boar semen can be used as a predictor of semen quality after storage. PMID:24729963

The Effect of the Wastewater of Penicillin and Amoxicillin on the Antioxidant Indexes of Limnodrilus Hoffmeisteri

NASA Astrophysics Data System (ADS)

Dong, Yuxin; Shen, Hongyan

2018-01-01

In order to obtain some basic data for ecological risk assessment, an exposure experiment was carried out to study the effect of different volume of mixed penicillin and amoxicillin wastewater on Superoxide Dismutase (SOD) and Malondialdehyde (MDA) in Limnodrilus hoffmeisteri. Limnodrilus hoffmeisteri was exposed to different volume (10%, 20%, 30%, 40%, and 50%) of mixed wastewater for 15 days. According to the experimental data, the MDA contents and SOD activities in Limnodrilus hoffmeisteri muscle tissue had seen significant change significantly during the period of exposure. The results showed that the trend of SOD activities in low concentration groups (10% and 20%) increased at first, then decreased and increased at last. As exposure concentration increased (40% and 50%), SOD activities were inhibited in the early days (3 d), and was gradually induced in the later phase. The change of MDA content in muscle tissue of Limnodrilus hoffmeisteri was further investigated. It was found to be negatively correlated with the activity of SOD, and the high concentration group (50%) was in a remarkable induction state and reached the maximum at 6 d. According to the experimental data, the MDA contents and SOD activities in Limnodrilus hoffmeisteri muscle tissue had changed significantly and caused the oxidative damage.

Characteristics of the Copper,Zinc Superoxide Dismutase of a Hadal Sea Cucumber (Paelopatides sp.) from the Mariana Trench.

PubMed

Li, Yanan; Kong, Xue; Chen, Jiawei; Liu, Helu; Zhang, Haibin

2018-05-18

Superoxide dismutases (SODs) are among the most important antioxidant enzymes and show great potential in preventing adverse effects during therapeutic trials. In the present study, cloning, expression, and characterization of a novel Cu,Zn superoxide dismutase (Ps-Cu,Zn-SOD) from a hadal sea cucumber ( Paelopatides sp.) were reported. Phylogenetic analysis showed that Ps-Cu,Zn-SOD belonged to a class of intracellular SOD. Its K m and V max were 0.0258 ± 0.0048 mM and 925.1816 ± 28.0430 units/mg, respectively. The low K m value of this enzyme represents a high substrate affinity and can adapt to the low metabolic rate of deep sea organisms. The enzyme functioned from 0 °C to 80 °C with an optimal temperature of 40 °C. Moreover, the enzyme activity was maintained up to 87.12% at 5 °C. The enzyme was active at pH 4 to 12 with an optimal pH of 8.5. Furthermore, Ps-Cu,Zn-SOD tolerated high concentration of urea and GuHCl, resisted hydrolysis by proteases, and maintained stability at high pressure. All these features demonstrated that the deep sea Ps-Cu,Zn-SOD is a potential candidate for application to the biopharmaceutical field.

Gene expression changes in spinal motoneurons of the SOD1(G93A) transgenic model for ALS after treatment with G-CSF.

PubMed

Henriques, Alexandre; Kastner, Stefan; Chatzikonstantinou, Eva; Pitzer, Claudia; Plaas, Christian; Kirsch, Friederike; Wafzig, Oliver; Krüger, Carola; Spoelgen, Robert; Gonzalez De Aguilar, Jose-Luis; Gretz, Norbert; Schneider, Armin

2014-01-01

Amyotrophic lateral sclerosis (ALS) is an incurable fatal motoneuron disease with a lifetime risk of approximately 1:400. It is characterized by progressive weakness, muscle wasting, and death ensuing 3-5 years after diagnosis. Granulocyte-colony stimulating factor (G-CSF) is a drug candidate for ALS, with evidence for efficacy from animal studies and interesting data from pilot clinical trials. To gain insight into the disease mechanisms and mode of action of G-CSF, we performed gene expression profiling on isolated lumbar motoneurons from SOD1(G93A) mice, the most frequently studied animal model for ALS, with and without G-CSF treatment. Motoneurons from SOD1(G93A) mice present a distinct gene expression profile in comparison to controls already at an early disease stage (11 weeks of age), when treatment was initiated. The degree of deregulation increases at a time where motor symptoms are obvious (15 weeks of age). Upon G-CSF treatment, transcriptomic deregulations of SOD1(G93A) motoneurons were notably restored. Discriminant analysis revealed that SOD1 mice treated with G-CSF has a transcriptom close to presymptomatic SOD1 mice or wild type mice. Some interesting genes modulated by G-CSF treatment relate to neuromuscular function such as CCR4-NOT or Prss12. Our data suggest that G-CSF is able to re-adjust gene expression in symptomatic SOD1(G93A) motoneurons. This provides further arguments for G-CSF as a promising drug candidate for ALS.

Redox regulation, gene expression and longevity.

PubMed

Honda, Yoko; Tanaka, Masashi; Honda, Shuji

2010-07-01

Lifespan can be lengthened by genetic and environmental modifications. Study of these might provide valuable insights into the mechanism of aging. Low doses of radiation and short-term exposure to heat and high concentrations of oxygen prolong the lifespan of the nematode Caenorhabditis elegans. These might be caused by adaptive responses to harmful environmental conditions. Single-gene mutations have been found to extend lifespan in C. elegans, Drosophila and mice. So far, the best-characterized system is the C. elegans mutant in the daf-2, insulin/IGF-I receptor gene that is the component of the insulin/IGF-I signaling pathway. The mutant animals live twice as long as the wild type. The insulin/IGF-I signaling pathway regulates the activity of DAF-16, a FOXO transcription factor. However, the unified explanation for the function of DAF-16 transcription targets in the lifespan extension is not yet fully established. As both of the Mn superoxide dismutase (MnSOD) isoforms (sod-2 and sod-3) are found to be targets of DAF-16, we attempted to assess their functions in regulating lifespan and oxidative stress responsivity. We show that the double deletions of sod-2 and sod-3 genes induced oxidative-stress sensitivity but do not shorten lifespan in the daf-2 mutant background, indicating that oxidative stress is not necessarily a limiting factor for longevity. Furthermore, the deletion in the sod-3 gene lengthens lifespan in the daf-2 mutant. We conclude that the MnSOD systems in C. elegans fine-tune the insulin/IGF-I-signaling based regulation of longevity by acting not as anti-oxidants but as physiological-redox-signaling modulators.

Cu, Zn-Superoxide Dismutase Increases the Therapeutic Potential of Adipose-derived Mesenchymal Stem Cells by Maintaining Antioxidant Enzyme Levels.

PubMed

Yoo, Dae Young; Kim, Dae Won; Chung, Jin Young; Jung, Hyo Young; Kim, Jong Whi; Yoon, Yeo Sung; Hwang, In Koo; Choi, Jung Hoon; Choi, Goang-Min; Choi, Soo Young; Moon, Seung Myung

2016-12-01

In the present study, we investigated the ability of Cu, Zn-superoxide dismutase (SOD1) to improve the therapeutic potential of adipose tissue-derived mesenchymal stem cells (Ad-MSCs) against ischemic damage in the spinal cord. Animals were divided into four groups: the control group, vehicle (PEP-1 peptide and artificial cerebrospinal fluid)-treated group, Ad-MSC alone group, and Ad-MSC-treated group with PEP-1-SOD1. The abdominal aorta of the rabbit was occluded for 30 min in the subrenal region to induce ischemic damage, and immediately after reperfusion, artificial cerebrospinal fluid or Ad-MSCs (2 × 10 5 ) were administered intrathecally. In addition, PEP-1 or 0.5 mg/kg PEP-1-SOD1 was administered intraperitoneally to the Ad-MSC-treated rabbits. Motor behaviors and NeuN-immunoreactive neurons were significantly decreased in the vehicle-treated group after ischemia/reperfusion. Administration of Ad-MSCs significantly ameliorated the changes in motor behavior and NeuN-immunoreactive neuronal survival. In addition, the combination of PEP-1-SOD1 and Ad-MSCs further increased the ameliorative effects of Ad-MSCs in the spinal cord after ischemia. Furthermore, the administration of Ad-MSCs with PEP-1-SOD1 decreased lipid peroxidation and maintained levels of antioxidants such as SOD1 and glutathione peroxidase compared to the Ad-MSC alone group. These results suggest that combination therapy using Ad-MSCs and PEP-1-SOD1 strongly protects neurons from ischemic damage by modulating the balance of lipid peroxidation and antioxidants.

Gene expression changes in spinal motoneurons of the SOD1G93A transgenic model for ALS after treatment with G-CSF

PubMed Central

Henriques, Alexandre; Kastner, Stefan; Chatzikonstantinou, Eva; Pitzer, Claudia; Plaas, Christian; Kirsch, Friederike; Wafzig, Oliver; Krüger, Carola; Spoelgen, Robert; Gonzalez De Aguilar, Jose-Luis; Gretz, Norbert; Schneider, Armin

2015-01-01

Background: Amyotrophic lateral sclerosis (ALS) is an incurable fatal motoneuron disease with a lifetime risk of approximately 1:400. It is characterized by progressive weakness, muscle wasting, and death ensuing 3–5 years after diagnosis. Granulocyte-colony stimulating factor (G-CSF) is a drug candidate for ALS, with evidence for efficacy from animal studies and interesting data from pilot clinical trials. To gain insight into the disease mechanisms and mode of action of G-CSF, we performed gene expression profiling on isolated lumbar motoneurons from SOD1G93A mice, the most frequently studied animal model for ALS, with and without G-CSF treatment. Results: Motoneurons from SOD1G93A mice present a distinct gene expression profile in comparison to controls already at an early disease stage (11 weeks of age), when treatment was initiated. The degree of deregulation increases at a time where motor symptoms are obvious (15 weeks of age). Upon G-CSF treatment, transcriptomic deregulations of SOD1G93A motoneurons were notably restored. Discriminant analysis revealed that SOD1 mice treated with G-CSF has a transcriptom close to presymptomatic SOD1 mice or wild type mice. Some interesting genes modulated by G-CSF treatment relate to neuromuscular function such as CCR4-NOT or Prss12. Conclusions: Our data suggest that G-CSF is able to re-adjust gene expression in symptomatic SOD1G93A motoneurons. This provides further arguments for G-CSF as a promising drug candidate for ALS. PMID:25653590

Cordyceps sinensis oral liquid prolongs the lifespan of the fruit fly, Drosophila melanogaster, by inhibiting oxidative stress.

PubMed

Zou, Yingxin; Liu, Yuxiang; Ruan, Minghua; Feng, Xu; Wang, Jiachun; Chu, Zhiyong; Zhang, Zesheng

2015-10-01

This study investigated the effect of Cordyceps sinensis oral liquid (CSOL) on the lifespan of Drosophila melanogaster (fruit fly). Following the lifelong treatment of fruit flies with CSOL, lifespan was examined. The activity of copper-zinc-containing superoxide dismutase 1 (SOD1), manganese-containing superoxide dismutase 2 (SOD2) and catalase (CAT), as well as the lipofuscin (LF) content were determined. The mRNA levels of SOD1, SOD2 and CAT were quantified by qPCR. Hydrogen peroxide (H2O2) and paraquat were used to mimic the effects of damage caused by acute oxidative stress. D-galactose was used to mimic chronic pathological aging. CSOL significantly prolonged the lifespan of the fruit flies under physiological conditions. The activity of SOD1 and CAT was upregulated, and LF accumulation was inhibited by CSOL. CSOL had no effect on the transcriptional levels (mRNA) of these enzymes. The survival time of the fruit flies which were negatively affected by exposure to H2O2 or paraquat was significantly prolonged by CSOL. In fruit flies pathologically aged by epxosure to D-galactose, CSOL also significantly prolonged their lifespan, upregulated the activity of SOD1 and CAT, and inhibited LF accumulation. The findings of our study indicate that CSOL prolongs the lifespan of fruit flies through an anti-oxidative stress pathway involving the upregulation of SOD1 and CAT activity and the inhibition of LF accumulation. CSOL may thus be explored as a novel agent for slowing the human aging process.

Differential Expression of Mitochondrial Manganese Superoxide Dismutase (SOD) in Triticum aestivum Exposed to Silver Nitrate and Silver Nanoparticles.

PubMed

Karimi, Javad; Mohsenzadeh, Sasan; Niazi, Ali; Moghadam, Ali

2017-01-01

Background: The increasing use of nanoparticles (NPs) may have negative impacts on both organisms and the environment. Objectives: The differential expression of mitochondrial manganese superoxide dismutase ( MnSOD ) gene in wheat in response to silver nitrate nanoparticles (AgNPs) and AgNO 3 was investigated. Materials and Methods: A quantitative Real-Time RT-PCR experiment was carried out with MnSOD gene using RNAs isolated from wheat shoots treated for 0, 2, 6, 12, and 24 h with 100 mg.L -1 of either AgNO 3 or AgNPs. Results: The results of this study showed that both treatments cause changes in the expression pattern of the MnSOD gene. While 2 and 6 h following the beginning of the stress, MnSOD expression was up-regulated significantly, in response to AgNO 3 (1.4 and 2.8 fold, respectively), in response to AgNPs, it was up-regulated significant only after 6 h (1.6 fold), compared with the control. The gene expression, after 12 h in response to AgNO 3 and AgNPs were downregulated significantly (0.7 and 0.8 fold, respectively), and in the next 12 h , the expression appeared to be similar to the control. Conclusion: Exposure to both AgNPs and Ag ions led to a significant increase in MnSOD expression, but AgNO 3 changed the MnSOD expression faster than AgNPs. Therefore, it is suggested that AgNO 3 has greater penetrability and effectiveness.

Extracellular Superoxide Dismutase Ameliorates Skeletal Muscle Abnormalities, Cachexia and Exercise Intolerance in Mice with Congestive Heart Failure

PubMed Central

Okutsu, Mitsuharu; Call, Jarrod A.; Lira, Vitor A.; Zhang, Mei; Donet, Jean A.; French, Brent A.; Martin, Kyle S.; Peirce-Cottler, Shayn M.; Rembold, Christopher M.; Annex, Brian H.; Yan, Zhen

2014-01-01

Background Congestive heart failure (CHF) is a leading cause of morbidity and mortality, and oxidative stress has been implicated in the pathogenesis of cachexia (muscle wasting) and the hallmark symptom, exercise intolerance. We have previously shown that a nitric oxide (NO)-dependent antioxidant defense renders oxidative skeletal muscle resistant to catabolic wasting. Here, we aimed to identify and determine the functional role of the NO-inducible antioxidant enzyme(s) in protection against cardiac cachexia and exercise intolerance in CHF. Methods and Results We demonstrated that systemic administration of endogenous nitric oxide donor S-Nitrosoglutathione in mice blocked the reduction of extracellular superoxide dismutase (EcSOD) protein expression, the induction of MAFbx/Atrogin-1 mRNA expression and muscle atrophy induced by glucocorticoid. We further showed that endogenous EcSOD, expressed primarily by type IId/x and IIa myofibers and enriched at endothelial cells, is induced by exercise training. Muscle-specific overexpression of EcSOD by somatic gene transfer or transgenesis [muscle creatine kinase (MCK)-EcSOD] in mice significantly attenuated muscle atrophy. Importantly, when crossbred into a mouse genetic model of CHF [α-myosin heavy chain (MHC)-calsequestrin] MCK-EcSOD transgenic mice had significant attenuation of cachexia with preserved whole body muscle strength and endurance capacity in the absence of reduced heart failure. Enhanced EcSOD expression significantly ameliorated CHF-induced oxidative stress, MAFbx/Atrogin-1 mRNA expression, loss of mitochondria and vascular rarefaction in skeletal muscle. Conclusions EcSOD plays an important antioxidant defense function in skeletal muscle against cardiac cachexia and exercise intolerance in CHF. PMID:24523418

Cordyceps sinensis oral liquid prolongs the lifespan of the fruit fly, Drosophila melanogaster, by inhibiting oxidative stress

PubMed Central

ZOU, YINGXIN; LIU, YUXIANG; RUAN, MINGHUA; FENG, XU; WANG, JIACHUN; CHU, ZHIYONG; ZHANG, ZESHENG

2015-01-01

This study investigated the effect of Cordyceps sinensis oral liquid (CSOL) on the lifespan of Drosophila melanogaster (fruit fly). Following the lifelong treatment of fruit flies with CSOL, lifespan was examined. The activity of copper-zinc-containing superoxide dismutase 1 (SOD1), manganese-containing superoxide dismutase 2 (SOD2) and catalase (CAT), as well as the lipofuscin (LF) content were determined. The mRNA levels of SOD1, SOD2 and CAT were quantified by qPCR. Hydrogen peroxide (H2O2) and paraquat were used to mimic the effects of damage caused by acute oxidative stress. D-galactose was used to mimic chronic pathological aging. CSOL significantly prolonged the lifespan of the fruit flies under physiological conditions. The activity of SOD1 and CAT was upregulated, and LF accumulation was inhibited by CSOL. CSOL had no effect on the transcriptional levels (mRNA) of these enzymes. The survival time of the fruit flies which were negatively affected by exposure to H2O2 or paraquat was significantly prolonged by CSOL. In fruit flies pathologically aged by epxosure to D-galactose, CSOL also significantly prolonged their lifespan, upregulated the activity of SOD1 and CAT, and inhibited LF accumulation. The findings of our study indicate that CSOL prolongs the lifespan of fruit flies through an anti-oxidative stress pathway involving the upregulation of SOD1 and CAT activity and the inhibition of LF accumulation. CSOL may thus be explored as a novel agent for slowing the human aging process. PMID:26239097

Potential linkage between sediment oxygen demand and pore water chemistry in weir-impounded rivers.

PubMed

Lee, Mi-Hee; Jung, Heon-Jae; Kim, Sung-Han; An, Sung-Uk; Choi, Jung Hyun; Lee, Hyo-Jin; Huh, In-Ae; Hur, Jin

2018-04-01

Due to recent weir construction on four major rivers in South Korea, sediment has accumulated in the river bottom near the weirs, which has in turn raised concerns over the quality of overlying water. In this study, the seasonal and spatial variations of sediment oxygen demand (SOD) and the influencing factors were explored using pore water chemistry for the weir-impounded rivers. Muddy and sandy sediment samples were taken from 24 different sites along the four major rivers in summer and autumn, 2016. The SOD was measured in a laboratory based on 10-hour incubation at in situ temperature. The measured pore water chemistry included the concentrations of dissolved organic carbon (DOC), total dissolved nitrogen (TDN), inorganic nitrogen (NH 3 -N, NO 3 -N, NO 2 -N), and phosphate phosphorous (PO 4 -P), and the optical properties from UV absorption spectra and fluorescence excitation-emission matrixes coupled with parallel factor analysis (EEM-PARAFAC). Significant differences in SOD values between muddy and sandy sediments were found only in summer (p=0.047). The higher SOD in summer versus autumn (p=0.015) was attributed to seasonal temperature differences. The higher NH 3 -N and the lower NO 3 -N of the pore water samples in summer versus autumn suggested that organic nitrogen decomposition via an ammonification and nitrification process could operate as an important factor for the SOD variations in summer and autumn, respectively. Principal component analysis revealed the mutual contributions of nitrogen-associated processes and the organic composition in pore water to increasing SOD levels. NH 3 -N in sediment pore water alone could be a good predictor for SOD. However, multiple regression analysis using NH 3 -N, fluorescence index and terrestrial humic-like components improved the estimation capability for SOD variations. Copyright © 2017 Elsevier B.V. All rights reserved.

Nickel Superoxide Dismutase: Structural and Functional Roles of His1 and its H-bonding Network

PubMed Central

Ryan, Kelly C.; Guce, Abigail I.; Johnson, Olivia E.; Brunold, Thomas C.; Cabelli, Diane E.; Garman, Scott C.; Maroney, Michael J.

2015-01-01

Crystal structures of nickel-dependent superoxide dismutases (NiSODs) reveal the presence of a H-bonding network formed between the N-H of the apical imidazole ligand from His1 and the Glu17 carboxylate from a neighboring subunit in the hexameric enzyme. This interaction is supported by another intra-subunit H-bond between Glu17 and Arg47. In this study, four mutant NiSOD proteins were produced to experimentally evaluate the roles of this H-bonding network, and compare the results with prior predictions from DFT calculations. H1A-NiSOD, which lacks the apical ligand entirely, was crystallographically characterized and reveals that in the absence of the Glu17-His1 H-bond, the active site is disordered. Subsequent characterization using X-ray absorption spectroscopy (XAS) shows that Ni(II) is bound in the expected N2S2 planar coordination site. Despite these structural perturbations, the H1A-NiSOD variant is an active catalyst with 4% of WT-NiSOD activity. Three other mutations were designed to preserve the apical imidazole ligand, but perturb the H-bonding network: R47A-NiSOD, lacks the intra-molecular H-bonding interaction, E17R/R47A-NiSOD, which retains the intra-molecular H-bond, but lacks the inter-molecular Glu17-His1 H-bond, and E17A/R47A-NiSOD, which lacks both H-bonding interactions. These variants were characterized by a combination of techniques including XAS characterization of the nickel site structure, kinetic studies employing pulse-radiolytic production of superoxide, and EPR and chemical probes of the redox activity. The results indicate that in addition to the roles in redox tuning suggested by the computational models, the Glu17-His1 H-bond plays an important structural role in the formation of the Ni-hook motif that is a critical feature of the active site. PMID:25580509

Altered mechanisms underlying the abnormal glutamate release in amyotrophic lateral sclerosis at a pre-symptomatic stage of the disease.

PubMed

Bonifacino, Tiziana; Musazzi, Laura; Milanese, Marco; Seguini, Mara; Marte, Antonella; Gallia, Elena; Cattaneo, Luca; Onofri, Franco; Popoli, Maurizio; Bonanno, Giambattista

2016-11-01

Abnormal Glu release occurs in the spinal cord of SOD1(G93A) mice, a transgenic animal model for human ALS. Here we studied the mechanisms underlying Glu release in spinal cord nerve terminals of SOD1(G93A) mice at a pre-symptomatic disease stage (30days) and found that the basal release of Glu was more elevated in SOD1(G93A) with respect to SOD1 mice, and that the surplus of release relies on synaptic vesicle exocytosis. Exposure to high KCl or ionomycin provoked Ca(2+)-dependent Glu release that was likewise augmented in SOD1(G93A) mice. Equally, the Ca(2+)-independent hypertonic sucrose-induced Glu release was abnormally elevated in SOD1(G93A) mice. Also in this case, the surplus of Glu release was exocytotic in nature. We could determine elevated cytosolic Ca(2+) levels, increased phosphorylation of Synapsin-I, which was causally related to the abnormal Glu release measured in spinal cord synaptosomes of pre-symptomatic SOD1(G93A) mice, and increased phosphorylation of glycogen synthase kinase-3 at the inhibitory sites, an event that favours SNARE protein assembly. Western blot experiments revealed an increased number of SNARE protein complexes at the nerve terminal membrane, with no changes of the three SNARE proteins and increased expression of synaptotagmin-1 and β-Actin, but not of an array of other release-related presynaptic proteins. These results indicate that the abnormal exocytotic Glu release in spinal cord of pre-symptomatic SOD1(G93A) mice is mainly based on the increased size of the readily releasable pool of vesicles and release facilitation, supported by plastic changes of specific presynaptic mechanisms. Copyright © 2016 Elsevier Inc. All rights reserved.

Deletion of galectin-3 exacerbates microglial activation and accelerates disease progression and demise in a SOD1G93A mouse model of amyotrophic lateral sclerosis

PubMed Central

Lerman, Bruce J; Hoffman, Eric P; Sutherland, Margaret L; Bouri, Khaled; Hsu, Daniel K; Liu, Fu-Tong; Rothstein, Jeffrey D; Knoblach, Susan M

2012-01-01

Galectins are pleiotropic carbohydrate-binding lectins involved in inflammation, growth/differentiation, and tissue remodeling. The functional role of galectins in amyotrophic lateral sclerosis (ALS) is unknown. Expression studies revealed increases in galectin-1 mRNA and protein in spinal cords from SOD1G93A mice, and in galectin-3 and -9 mRNAs and proteins in spinal cords of both SOD1G93A mice and sporadic ALS patients. As the increase in galectin-3 appeared in early presymptomatic stages and increased progressively through to end stage of disease in the mouse, it was selected for additional study, where it was found to be mainly expressed by microglia. Galectin-3 antagonists are not selective and do not readily cross the blood–brain barrier; therefore, we generated SOD1G93A/Gal-3−/− transgenic mice to evaluate galectin-3 deletion in a widely used mouse model of ALS. Disease progression, neurological symptoms, survival, and inflammation were assessed to determine the effect of galectin-3 deletion on the SOD1G93A disease phenotype. Galectin-3 deletion did not change disease onset, but resulted in more rapid progression through functionally defined disease stages, more severely impaired neurological symptoms at all stages of disease, and expiration, on average, 25 days earlier than SOD1G93A/Gal-3+/+ cohorts. In addition, microglial staining, as well as TNF-α, and oxidative injury were increased in SOD1G93A/Gal-3−/− mice compared with SOD1G93A/Gal-3+/+ cohorts. These data support an important functional role for microglial galectin-3 in neuroinflammation during chronic neurodegenerative disease. We suggest that elevations in galectin-3 by microglia as disease progresses may represent a protective, anti-inflammatory innate immune response to chronic motor neuron degeneration. PMID:23139902

Reactive oxygen species trigger motoneuron death in non-cell-autonomous models of ALS through activation of c-Abl signaling.

PubMed

Rojas, Fabiola; Gonzalez, David; Cortes, Nicole; Ampuero, Estibaliz; Hernández, Diego E; Fritz, Elsa; Abarzua, Sebastián; Martinez, Alexis; Elorza, Alvaro A; Alvarez, Alejandra; Court, Felipe; van Zundert, Brigitte

2015-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease in which pathogenesis and death of motor neurons are triggered by non-cell-autonomous mechanisms. We showed earlier that exposing primary rat spinal cord cultures to conditioned media derived from primary mouse astrocyte conditioned media (ACM) that express human SOD1(G93A) (ACM-hSOD1(G93A)) quickly enhances Nav channel-mediated excitability and calcium influx, generates intracellular reactive oxygen species (ROS), and leads to death of motoneurons within days. Here we examined the role of mitochondrial structure and physiology and of the activation of c-Abl, a tyrosine kinase that induces apoptosis. We show that ACM-hSOD1(G93A), but not ACM-hSOD1(WT), increases c-Abl activity in motoneurons, interneurons and glial cells, starting at 60 min; the c-Abl inhibitor STI571 (imatinib) prevents this ACM-hSOD1(G93A)-mediated motoneuron death. Interestingly, similar results were obtained with ACM derived from astrocytes expressing SOD1(G86R) or TDP43(A315T). We further find that co-application of ACM-SOD1(G93A) with blockers of Nav channels (spermidine, mexiletine, or riluzole) or anti-oxidants (Trolox, esculetin, or tiron) effectively prevent c-Abl activation and motoneuron death. In addition, ACM-SOD1(G93A) induces alterations in the morphology of neuronal mitochondria that are related with their membrane depolarization. Finally, we find that blocking the opening of the mitochondrial permeability transition pore with cyclosporine A, or inhibiting mitochondrial calcium uptake with Ru360, reduces ROS production and c-Abl activation. Together, our data point to a sequence of events in which a toxic factor(s) released by ALS-expressing astrocytes rapidly induces hyper-excitability, which in turn increases calcium influx and affects mitochondrial structure and physiology. ROS production, mediated at least in part through mitochondrial alterations, trigger c-Abl signaling and lead to motoneuron death.

Astrocytes expressing mutant SOD1 and TDP43 trigger motoneuron death that is mediated via sodium channels and nitroxidative stress

PubMed Central

Rojas, Fabiola; Cortes, Nicole; Abarzua, Sebastian; Dyrda, Agnieszka; van Zundert, Brigitte

2013-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal paralytic disorder caused by dysfunction and degeneration of motor neurons. Multiple disease-causing mutations, including in the genes for SOD1 and TDP-43, have been identified in ALS. Astrocytes expressing mutant SOD1 are strongly implicated in the pathogenesis of ALS: we have shown that media conditioned by astrocytes carrying mutant SOD1G93A contains toxic factor(s) that kill motoneurons by activating voltage-sensitive sodium (Nav) channels. In contrast, a recent study suggests that astrocytes expressing mutated TDP43 contribute to ALS pathology, but do so via cell-autonomous processes and lack non-cell-autonomous toxicity. Here we investigate whether astrocytes that express diverse ALS-causing mutations release toxic factor(s) that induce motoneuron death, and if so, whether they do so via a common pathogenic pathway. We exposed primary cultures of wild-type spinal cord cells to conditioned medium derived from astrocytes (ACM) that express SOD1 (ACM-SOD1G93A and ACM-SOD1G86R) or TDP43 (ACM-TDP43A315T) mutants; we show that such exposure rapidly (within 30–60 min) increases dichlorofluorescein (DCF) fluorescence (indicative of nitroxidative stress) and leads to extensive motoneuron-specific death within a few days. Co-application of the diverse ACMs with anti-oxidants Trolox or esculetin (but not with resveratrol) strongly improves motoneuron survival. We also find that co-incubation of the cultures in the ACMs with Nav channel blockers (including mexiletine, spermidine, or riluzole) prevents both intracellular nitroxidative stress and motoneuron death. Together, our data document that two completely unrelated ALS models lead to the death of motoneuron via non-cell-autonomous processes, and show that astrocytes expressing mutations in SOD1 and TDP43 trigger such cell death through a common pathogenic pathway that involves nitroxidative stress, induced at least in part by Nav channel activity. PMID:24570655

Nickel superoxide dismutase: structural and functional roles of His1 and its H-bonding network

DOE PAGES

Maroney, Michael J.; Cabelli, Diane E.; Ryan, Kelly C.; ...

2015-01-21

Crystal structures of nickel-dependent superoxide dismutases (NiSODs) reveal the presence of a H-bonding network formed between the NH group of the apical imidazole ligand from His1 and the Glu17 carboxylate from a neighboring subunit in the hexameric enzyme. This interaction is supported by another intrasubunit H-bond between Glu17 and Arg47. In this study, four mutant NiSOD proteins were produced to experimentally evaluate the roles of this H-bonding network and compare the results with prior predictions from density functional theory calculations. The X-ray crystal structure of H1A-NiSOD, which lacks the apical ligand entirely, reveals that in the absence of the Glu17-His1more » H-bond, the active site is disordered. Characterization of this variant using X-ray absorption spectroscopy (XAS) shows that Ni(II) is bound in the expected N₂S₂ planar coordination site. Despite these structural perturbations, the H1A-NiSOD variant retains 4% of wild-type (WT) NiSOD activity. Three other mutations were designed to preserve the apical imidazole ligand but perturb the H-bonding network: R47A-NiSOD, which lacks the intramolecular H-bonding interaction; E17R/R47A-NiSOD, which retains the intramolecular H-bond but lacks the intermolecular Glu17-His1 H-bond; and E17A/R47ANiSOD, which lacks both H-bonding interactions. These variants were characterized by a combination of techniques, including XAS to probe the nickel site structure, kinetic studies employing pulse-radiolytic production of superoxide, and electron paramagnetic resonance to assess the Ni redox activity. The results indicate that in addition to the roles in redox tuning suggested on the basis of previous computational studies, the Glu17-His1 H-bond plays an important structural role in the proper folding of the “Ni-hook” motif that is a critical feature of the active site.« less

Delayed disease onset and extended survival in the SOD1G93A rat model of amyotrophic lateral sclerosis after suppression of mutant SOD1 in the motor cortex.

PubMed

Thomsen, Gretchen M; Gowing, Genevieve; Latter, Jessica; Chen, Maximus; Vit, Jean-Philippe; Staggenborg, Kevin; Avalos, Pablo; Alkaslasi, Mor; Ferraiuolo, Laura; Likhite, Shibi; Kaspar, Brian K; Svendsen, Clive N

2014-11-19

Sporadic amyotrophic lateral sclerosis (ALS) is a fatal disease with unknown etiology, characterized by a progressive loss of motor neurons leading to paralysis and death typically within 3-5 years of onset. Recently, there has been remarkable progress in understanding inherited forms of ALS in which well defined mutations are known to cause the disease. Rodent models in which the superoxide dismutase-1 (SOD1) mutation is overexpressed recapitulate hallmark signs of ALS in patients. Early anatomical changes in mouse models of fALS are seen in the neuromuscular junctions (NMJs) and lower motor neurons, and selective reduction of toxic mutant SOD1 in the spinal cord and muscle of these models has beneficial effects. Therefore, much of ALS research has focused on spinal motor neuron and NMJ aspects of the disease. Here we show that, in the SOD1(G93A) rat model of ALS, spinal motor neuron loss occurs presymptomatically and before degeneration of ventral root axons and denervation of NMJs. Although overt cell death of corticospinal motor neurons does not occur until disease endpoint, we wanted to establish whether the upper motor neuron might still play a critical role in disease progression. Surprisingly, the knockdown of mutant SOD1 in only the motor cortex of presymptomatic SOD1(G93A) rats through targeted delivery of AAV9-SOD1-shRNA resulted in a significant delay of disease onset, expansion of lifespan, enhanced survival of spinal motor neurons, and maintenance of NMJs. This datum suggests an early dysfunction and thus an important role of the upper motor neuron in this animal model of ALS and perhaps patients with the disease. Copyright © 2014 the authors 0270-6474/14/3415587-14$15.00/0.

Physicochemical properties and carbon density of alpine sod layer with their variation across habitat gradients in the Zoige Plateau

NASA Astrophysics Data System (ADS)

Peixi, Su; Zijuan, Zhou; Rui, Shi; tingting, Xie

2017-04-01

The alpine sod layer is a soft, tough and resistant to shifting surface soil layer under the formation of the natural vegetation in the plateau cold region, understanding its ecological function is a prerequisite to promote grass and animal husbandry production for recuperation and protection, and the active use of project construction. Based on the extensive investigation on the alpine vegetation of the Zoige Plateau in the Eastern Qinghai-Tibetan Plateau of China, set up moisture gradient community sample plots: swamp, degraded swamp, swampy meadow, wet meadow, dry meadow and degraded meadow, and the elevation gradient community sample plots: subalpine meadow, subalpine shrub meadow, alpine shrub meadow and alpine meadow were set up. The sod layer bulk density, soil particle composition and soil organic carbon (SOC) content of different types of community plots were analyzed and to compare its carbon sequestration capacity on the moisture and elevation gradients. The results showed that the average thickness of the sod layer was 30 cm, the bulk density of the swamp was the smallest, and the SOC content was above 300 g/kg. The bulk density of degraded meadow was the highest while its SOC content was decreased significantly. The SOC density of sod layer in different communities was between 10 and 24 kg C/m2, and decreased with the decreasing of soil water availability, and meadow degradation significantly decreased the soil organic carbon storage in sod layer. The sod layer SOC density of alpine shrub meadow was 15% higher than that of meadow on the altitudinal gradient. It was concluded that the mass water content threshold value for maintaining the sod layer stable is 30%. In the degraded succession of alpine vegetation from swamp to meadow, the bulk density and compactness of sod layer became larger, while the organic carbon content, carbon density and carbon storage decreased. The higher the gravel content of swamp, the more easily degraded, and the higher the sand content of the meadow, the more easily degraded. Shrub meadow had higher carbon sequestration capacity than that of meadow, but the productive function of shrub meadow was lower. Keeping the sustainable development of grassland productivity and maintaining the carbon sequestration ecological function, it is necessary to prevent the degradation of the sod layer, and restrain the succession from meadow to scrub meadow. Key Words: surface soil layer, soil organic carbon, carbon density, alpine vegetation, Zoige Plateau

ALS-associated mutation SOD1G93A leads to abnormal mitochondrial dynamics in osteocytes.

PubMed

Wang, Huan; Yi, Jianxun; Li, Xuejun; Xiao, Yajuan; Dhakal, Kamal; Zhou, Jingsong

2018-01-01

While the death of motor neuron is a pathological hallmark of amyotrophic lateral sclerosis (ALS), defects in other cell types or organs may also actively contribute to ALS disease progression. ALS patients experience progressive skeletal muscle wasting that may not only exacerbate neuronal degeneration, but likely has a significant impact on bone function. In our previous published study, we have discovered severe bone loss in an ALS mouse model with overexpression of ALS-associated mutation SOD1 G93A (G93A). Here we further provide a mechanistic understanding of the bone loss in ALS animal and cellular models. Combining mitochondrial fluorescent indicators and confocal live cell imaging, we discovered abnormalities in mitochondrial network and dynamics in primary osteocytes derived from the same ALS mouse model G93A. Those mitochondrial defects occur in ALS mice after the onset of neuromuscular symptoms, indicating that mitochondria in bone cells respond to muscle atrophy during ALS disease progression. To examine whether ALS mutation has a direct contribution to mitochondrial dysfunction independent of muscle atrophy, we evaluated mitochondrial morphology and motility in cultured osteocytes (MLO-Y4) with overexpression of mitochondrial targeted SOD1 G93A . Compared with osteocytes overexpressing the wild type SOD1 as a control, the SOD1 G93A osteocytes showed similar defects in mitochondrial network and dynamic as that of the primary osteocytes derived from the ALS mouse model. In addition, we further discovered that overexpression of SOD1 G93A enhanced the expression level of dynamin-related protein 1 (Drp1), a key protein promoting mitochondrial fission activity, and reduced the expression level of optic atrophy protein 1 (OPA1), a key protein related to mitochondrial fusion. A specific mitochondrial fission inhibitor (Mdivi-1) partially reversed the effect of SOD1 G93A on mitochondrial network and dynamics, indicating that SOD1 G93A likely promotes mitochondrial fission, but suppresses the fusion activity. Our data provide the first evidence that mitochondria show abnormality in osteocytes derived from an ALS mouse model. The accumulation of mutant SOD1 G93A protein inside mitochondria directly causes dysfunction in mitochondrial dynamics in cultured MLO-Y4 osteocytes. In addition, the ALS mutation SOD1 G93A -mediated dysfunction in mitochondrial dynamics is associated with an enhanced apoptosis in osteocytes, which could be a potential mechanism underlying the bone loss during ALS progression. Copyright © 2017 Elsevier Inc. All rights reserved.

Plasma extracellular superoxide dismutase concentration, allelic variations in the SOD3 gene and risk of myocardial infarction and all-cause mortality in people with type 1 and type 2 diabetes.

PubMed

Mohammedi, Kamel; Bellili-Muñoz, Naïma; Marklund, Stefan L; Driss, Fathi; Le Nagard, Hervé; Patente, Thiago A; Fumeron, Frédéric; Roussel, Ronan; Hadjadj, Samy; Marre, Michel; Velho, Gilberto

2015-01-15

Oxidative stress is involved in development of diabetes complications. Extracellular superoxide dismutase (EC-SOD, SOD3) is a major extracellular antioxidant enzyme and is highly expressed in arterial walls. Advanced oxidation protein products (AOPP) and 8-iso-prostaglandin (isoprostane) are markers of oxidative stress. We investigated association of SOD3 gene variants, plasma concentrations of EC-SOD, AOPP and isoprostane with myocardial infarction and mortality in diabetic patients. We studied three cohorts designed to evaluate the vascular complications of diabetes: the GENEDIAB study (469 participants with type 1 diabetes at baseline; follow-up data for 259 participants), the GENESIS study (603 participants with type 1 diabetes at baseline; follow-up data for 525 participants) and the DIABHYCAR study (3137 participants with type 2 diabetes at baseline and follow-up). Duration of follow-up was 9, 5, and 5 years, respectively. Main outcome measures were incidence of myocardial infarction, and cardiovascular and total mortality during follow-up. Six single nucleotide polymorphisms in the SOD3 locus were genotyped in the three cohorts. Plasma concentrations of EC-SOD, AOPP, and isoprostane were measured in baseline samples of GENEDIAB participants. In GENEDIAB/GENESIS pooled cohorts, the minor T-allele of rs2284659 variant was inversely associated with the prevalence at baseline (Odds Ratio 0.48, 95% CI 0.29-0.78, p = 0.004) and the incidence during follow-up of myocardial infarction (Hazard Ratio 0.58, 95% CI 0.40-0.83, p = 0.003) and with cardiovascular (HR 0.33, 95% CI 0.08-0.74, p = 0.004) and all-cause mortality (HR 0.44, 95% CI 0.21-0.73, p = 0.0006). The protective allele was associated with higher plasma EC-SOD and lower plasma AOPP concentrations in GENEDIAB. It was also inversely associated with incidence of myocardial infarction (HR 0.75, 95% CI 0.59-0.94, p = 0.01) and all-cause mortality (HR 0.87, 95% CI 0.79-0.97, p = 0.008) in DIABHYCAR. The T-allele of rs2284659 in the promoter of SOD3 was associated with a more favorable plasma redox status and with better cardiovascular outcomes in diabetic patients. Our results suggest that EC-SOD plays an important role in the mechanisms of vascular protection against diabetes-related oxidative stress.

Oxygen free radical induced damage in kidneys subjected to warm ischemia and reperfusion. Protective effect of superoxide dismutase.

PubMed Central

Baker, G L; Corry, R J; Autor, A P

1985-01-01

Superoxide anion free radical (O2-.) has been implicated in the pathogenesis of tissue injury consequent to ischemia/reperfusion in several different organs, including heart and bowel. Superoxide dismutase (SOD), an enzyme free radical scavenger specific for O2-., has been used successfully to protect these organs from structural damage during reoxygenation of ischemic tissue. It has been suggested that the catalytic action of xanthine oxidase in injured tissue is an important source of O2-. during reoxygenation. In order to evaluate the potential of SOD to protect against kidney damage resulting from transient ischemia followed by reperfusion with oxygenated blood, a model of warm renal ischemia was studied. LBNF1 rats underwent right nephrectomy and occlusion of the left renal artery for 45 minutes. Survival in the group of ischemic untreated rats (N = 30) was 56% at 7 days and serum creatinine was greatly elevated (p less than 0.01) in rats remaining alive over the full 7-day period. In strong contrast to these results, all of the animals treated with SOD before reperfusion (N = 18) were alive after 7 days similar to sham operated control rats (N = 8). Serum creatinine in the SOD treated rats was significantly elevated only to postoperative day 3 and thereafter returned to normal. Rats treated with inactive SOD (N = 4) or SOD before ischemia (N = 4) had decreased survival rates compared to ischemic untreated animals and prolonged elevation of serum creatinine. When the ischemia time was extended to 60 minutes, only 19% of the untreated animals (N = 16) survived at 7 days whereas nearly 60% of the SOD-treated animals survived (N = 19). Serum creatinine was greatly elevated during the full 7-day observation period in all surviving rats in the untreated ischemic group, whereas serum creatinine returned to normal (p less than 0.05) after 4 days in the surviving rats treated with SOD. To test whether the action of xanthine oxidase contributed to the kidney damage after reoxygenation, 45 min. ischemic rat kidneys were treated with allopurinol. All of the animals treated with allopurinol (N = 12) were alive at 7 days. Serum creatinine values returned to normal after the episode of ischemia and reperfusion but more slowly than after SOD treatment. Histologic evaluation of kidney tissue taken from animals after ischemia alone showed extensive renal tubular damage, which was essentially absent in kidneys from SOD-treated animals.(ABSTRACT TRUNCATED AT 400 WORDS) Images FIG. 3. FIG. 4. FIG. 5. FIG. 6. FIG. 7. PMID:3840348

[Antimutagenic action of superoxide dismutase on sodium azide- and nitrosoguanidine-induced mutagenesis in Salmonella typhimurium TA 1535].

PubMed

Vorob'eva, L I; Cherdyntseva, T A; Aver'ianov, A A; Abilev, S K

1993-05-01

It was shown that superoxide dismutase (SOD) decreased the mutagenic action of sodium azide (NaN3) and N-methyl-N'-nitro-N-nitrosoguanidine in Salmonella typhimurium TA1535. Catalase and quenchers of hydroxyl radicals showed, unlike SOD no effect on the mutagenicity of NaN3. Cell extract from propionic acid bacteria also possessed the antimutagenic activity, only partially depending on the SOD activity.

Metabolic analysis of the synthesis of high levels of intracellular human SOD in Saccharomyces cerevisiae rhSOD 2060 411 SGA122.

PubMed

Gonzalez, Ramon; Andrews, Barbara A; Molitor, Julia; Asenjo, Juan A

2003-04-20

The synthesis of human superoxide dismutase (SOD) in batch cultures of a Saccharomyces cerevisiae strain using a glucose-limited minimal medium was studied through metabolic flux analysis. A stoichiometric model was built, which included 78 reactions, according to metabolic pathways operative in these strains during respirofermentative and oxidative metabolism. It allowed calculation of the distribution of metabolic fluxes during diauxic growth on glucose and ethanol. Fermentation profiles and metabolic fluxes were analyzed at different phases of diauxic growth for the recombinant strain (P+) and for its wild type (P-). The synthesis of SOD by the strain P+ resulted in a decrease in specific growth rate of 34 and 54% (growth on glucose and ethanol respectively) in comparison to the wild type. Both strains exhibited similar flux of glucose consumption and ethanol synthesis but important differences in carbon distribution with biomass/substrate yields and ATP production 50% higher in P-. A higher contribution of fermentative metabolism, with 64% of the energy produced at the phosphorylation level, was observed during SOD production. The flux of precursors to amino acids and nucleotides was higher in the recombinant strain, in agreement with the higher total RNA and protein levels. Lower specific growth rates in strain P+ appear to be related to the decrease in the rate of synthesis of nonrecombinant protein, as well as a decrease in the activities of the pentose phosphate (PP) pathway and TCA cycle. A very different way of entry into the stationary phase was observed for each strain: in the wild-type strain most metabolic fluxes decreased and fluxes related to energy reserve synthesis increased, while in the P+ strain the flux of 22 reactions (including PP pathway and amino acids biosynthesis) related to SOD production increased their fluxes. Changes in SOD production rates at different physiological states appear to be related to the differences in building blocks availability between respirofermentative and oxidative metabolism. Using the present expression system, ideal conditions for SOD synthesis are represented by either active growth during respirofermentative metabolism or transition from a growing to a nongrowing state. An increase in SOD flux could be achieved using an expression system nonassociated to growth and potentially eliminating part of the metabolic burden. Copyright 2003 Wiley Periodicals, Inc.

The TrkAIII oncoprotein inhibits mitochondrial free radical ROS-induced death of SH-SY5Y neuroblastoma cells by augmenting SOD2 expression and activity at the mitochondria, within the context of a tumour stem cell-like phenotype.

PubMed

Ruggeri, Pierdomenico; Farina, Antonietta R; Di Ianni, Natalia; Cappabianca, Lucia; Ragone, Marzia; Ianni, Giulia; Gulino, Alberto; Mackay, Andrew R

2014-01-01

The developmental and stress-regulated alternative TrkAIII splice variant of the NGF receptor TrkA is expressed by advanced stage human neuroblastomas (NBs), correlates with worse outcome in high TrkA expressing unfavourable tumours and exhibits oncogenic activity in NB models. In the present study, we report that constitutive TrkAIII expression in human SH-SY5Y NB cells inhibits Rotenone, Paraquat and LY83583-induced mitochondrial free radical reactive oxygen species (ROS)-mediated death by stimulating SOD2 expression, increasing mitochondrial SOD2 activity and attenuating mitochondrial free radical ROS production, in association with increased mitochondrial capacity to produce H2O2, within the context of a more tumour stem cell-like phenotype. This effect can be reversed by the specific TrkA tyrosine kinase inhibitor GW441756, by the multi-kinase TrkA inhibitors K252a, CEP-701 and Gö6976, which inhibit SOD2 expression, and by siRNA knockdown of SOD2 expression, which restores the sensitivity of TrkAIII expressing SH-SY5Y cells to Rotenone, Paraquat and LY83583-induced mitochondrial free radical ROS production and ROS-mediated death. The data implicate the novel TrkAIII/SOD2 axis in promoting NB resistance to mitochondrial free radical-mediated death and staminality, and suggest that the combined use of TrkAIII and/or SOD2 inhibitors together with agents that induce mitochondrial free radical ROS-mediated death could provide a therapeutic advantage that may also target the stem cell niche in high TrkA expressing unfavourable NB.

The TrkAIII Oncoprotein Inhibits Mitochondrial Free Radical ROS-Induced Death of SH-SY5Y Neuroblastoma Cells by Augmenting SOD2 Expression and Activity at the Mitochondria, within the Context of a Tumour Stem Cell-like Phenotype

PubMed Central

Di Ianni, Natalia; Cappabianca, Lucia; Ragone, Marzia; Ianni, Giulia; Gulino, Alberto; Mackay, Andrew R.

2014-01-01

The developmental and stress-regulated alternative TrkAIII splice variant of the NGF receptor TrkA is expressed by advanced stage human neuroblastomas (NBs), correlates with worse outcome in high TrkA expressing unfavourable tumours and exhibits oncogenic activity in NB models. In the present study, we report that constitutive TrkAIII expression in human SH-SY5Y NB cells inhibits Rotenone, Paraquat and LY83583-induced mitochondrial free radical reactive oxygen species (ROS)-mediated death by stimulating SOD2 expression, increasing mitochondrial SOD2 activity and attenuating mitochondrial free radical ROS production, in association with increased mitochondrial capacity to produce H2O2, within the context of a more tumour stem cell-like phenotype. This effect can be reversed by the specific TrkA tyrosine kinase inhibitor GW441756, by the multi-kinase TrkA inhibitors K252a, CEP-701 and Gö6976, which inhibit SOD2 expression, and by siRNA knockdown of SOD2 expression, which restores the sensitivity of TrkAIII expressing SH-SY5Y cells to Rotenone, Paraquat and LY83583-induced mitochondrial free radical ROS production and ROS-mediated death. The data implicate the novel TrkAIII/SOD2 axis in promoting NB resistance to mitochondrial free radical-mediated death and staminality, and suggest that the combined use of TrkAIII and/or SOD2 inhibitors together with agents that induce mitochondrial free radical ROS-mediated death could provide a therapeutic advantage that may also target the stem cell niche in high TrkA expressing unfavourable NB. PMID:24736663

Molecular identification of Nocardia species using the sodA gene: Identificación molecular de especies de Nocardia utilizando el gen sodA.

PubMed

Sánchez-Herrera, K; Sandoval, H; Mouniee, D; Ramírez-Durán, N; Bergeron, E; Boiron, P; Sánchez-Saucedo, N; Rodríguez-Nava, V

2017-09-01

Currently for bacterial identification and classification the rrs gene encoding 16S rRNA is used as a reference method for the analysis of strains of the genus Nocardia. However, it does not have enough polymorphism to differentiate them at the species level. This fact makes it necessary to search for molecular targets that can provide better identification. The sod A gene (encoding the enzyme superoxide dismutase) has had good results in identifying species of other Actinomycetes. In this study the sod A gene is proposed for the identification and differentiation at the species level of the genus Nocardia. We used 41 type species of various collections; a 386 bp fragment of the sod A gene was amplified and sequenced, and a phylogenetic analysis was performed comparing the genes rrs (1171 bp), hsp 65 (401 bp), sec A1 (494 bp), gyr B (1195 bp) and rpo B (401 bp). The sequences were aligned using the Clustal X program. Evolutionary trees according to the neighbour-joining method were created with the programs Phylo_win and MEGA 6. The specific variability of the sod A genus of the genus Nocardia was analysed. A high phylogenetic resolution, significant genetic variability, and specificity and reliability were observed for the differentiation of the isolates at the species level. The polymorphism observed in the sod A gene sequence contains variable regions that allow the discrimination of closely related Nocardia species. The clear specificity, despite its small size, proves to be of great advantage for use in taxonomic studies and clinical diagnosis of the genus Nocardia.

Mitochondria-derived hydrogen peroxide selectively enhances T cell receptor-initiated signal transduction.

PubMed

Gill, Tejpal; Levine, Alan D

2013-09-06

T cell receptor (TCR)-initiated signal transduction is reported to increase production of intracellular reactive oxygen species, such as superoxide (O2˙(-)) and hydrogen peroxide (H2O2), as second messengers. Although H2O2 can modulate signal transduction by inactivating protein phosphatases, the mechanism and the subcellular localization of intracellular H2O2 as a second messenger of the TCR are not known. The antioxidant enzyme superoxide dismutase (SOD) catalyzes the dismutation of highly reactive O2˙(-) into H2O2 and thus acts as an intracellular generator of H2O2. As charged O2˙(-) is unable to diffuse through intracellular membranes, cells express distinct SOD isoforms in the cytosol (Cu,Zn-SOD) and mitochondria (Mn-SOD), where they locally scavenge O2˙(-) leading to production of H2O2. A 2-fold organelle-specific overexpression of either SOD in Jurkat T cell lines increases intracellular production of H2O2 but does not alter the levels of intracellular H2O2 scavenging enzymes such as catalase, membrane-bound peroxiredoxin1 (Prx1), and cytosolic Prx2. We report that overexpression of Mn-SOD enhances tyrosine phosphorylation of TCR-associated membrane proximal signal transduction molecules Lck, LAT, ZAP70, PLCγ1, and SLP76 within 1 min of TCR cross-linking. This increase in mitochondrial H2O2 specifically modulates MAPK signaling through the JNK/cJun pathway, whereas overexpressing Cu,Zn-SOD had no effect on any of these TCR-mediated signaling molecules. As mitochondria translocate to the immunological synapse during TCR activation, we hypothesize this translocation provides the effective concentration of H2O2 required to selectively modulate downstream signal transduction pathways.

Superoxide dismutase 1 is positively selected to minimize protein aggregation in great apes.

PubMed

Dasmeh, Pouria; Kepp, Kasper P

2017-08-01

Positive (adaptive) selection has recently been implied in human superoxide dismutase 1 (SOD1), a highly abundant antioxidant protein with energy signaling and antiaging functions, one of very few examples of direct selection on a human protein product (exon); the molecular drivers of this selection are unknown. We mapped 30 extant SOD1 sequences to the recently established mammalian species tree and inferred ancestors, key substitutions, and signatures of selection during the protein's evolution. We detected elevated substitution rates leading to great apes (Hominidae) at ~1 per 2 million years, significantly higher than in other primates and rodents, although these paradoxically generally evolve much faster. The high evolutionary rate was partly due to relaxation of some selection pressures and partly to distinct positive selection of SOD1 in great apes. We then show that higher stability and net charge and changes at the dimer interface were selectively introduced upon separation from old world monkeys and lesser apes (gibbons). Consequently, human, chimpanzee and gorilla SOD1s have a net charge of -6 at physiological pH, whereas the closely related gibbons and macaques have -3. These features consistently point towards selection against the malicious aggregation effects of elevated SOD1 levels in long-living great apes. The findings mirror the impact of human SOD1 mutations that reduce net charge and/or stability and cause ALS, a motor neuron disease characterized by oxidative stress and SOD1 aggregates and triggered by aging. Our study thus marks an example of direct selection for a particular chemical phenotype (high net charge and stability) in a single human protein with possible implications for the evolution of aging.

Isolation and in silico analysis of Fe-superoxide dismutase in the cyanobacterium Nostoc commune.

PubMed

Kesheri, Minu; Kanchan, Swarna; Richa; Sinha, Rajeshwar P

2014-12-15

Cyanobacteria are known to endure various stress conditions due to the inbuilt potential for oxidative stress alleviation owing to the presence of an array of antioxidants. The present study shows that Antarctic cyanobacterium Nostoc commune possesses two antioxidative enzymes viz., superoxide dismutase (SOD) and catalase that jointly cope with environmental stresses prevailing at its natural habitat. Native-PAGE analysis illustrates the presence of a single prominent isoform recognized as Fe-SOD and three distinct isoforms of catalase. The protein sequence of Fe-SOD in N. commune retrieved from NCBI protein sequence database was used for in silico analysis. 3D structure of N. commune was predicted by comparative modeling using MODELLER 9v11. Further, this model was validated for its quality by Ramachandran plot, ERRAT, Verify 3D and ProSA-web which revealed good structure quality of the model. Multiple sequence alignment showed high conservation in N and C-terminal domain regions along with all metal binding positions in Fe-SOD which were also found to be highly conserved in all 28 cyanobacterial species under study, including N. commune. In silico prediction of isoelectric point and molecular weight of Fe-SOD was found to be 5.48 and 22,342.98Da respectively. The phylogenetic tree revealed that among 28 cyanobacterial species, Fe-SOD in N. commune was the closest evolutionary homolog of Fe-SOD in Nostoc punctiforme as evident by strong bootstrap value. Thus, N. commune may serve as a good biological model for studies related to survival of life under extreme conditions prevailing at the Antarctic region. Moreover cyanobacteria may be exploited for biochemical and biotechnological applications of enzymatic antioxidants. Copyright © 2014 Elsevier B.V. All rights reserved.

Interaction between dimer interface residues of native and mutated SOD1 protein: a theoretical study.

PubMed

Keerthana, S P; Kolandaivel, P

2015-04-01

Cu-Zn superoxide dismutase 1 (SOD1) is a highly conserved bimetallic protein enzyme, used for the scavenging the superoxide radicals (O2 (-)) produced due to aerobic metabolism in the mitochondrial respiratory chain. Over 100 mutations have been identified and found to be in the homodimeric structure of SOD1. The enzyme has to be maintained in its dimeric state for the structural stability and enzymatic activity. From our investigation, we found that the mutations apart from the dimer interface residues are found to affect the dimer stability of protein and hence enhancing the aggregation and misfolding tendency of mutated protein. The homodimeric state of SOD1 is found to be held together by the non-covalent interactions. The molecular dynamics simulation has been used to study the hydrogen bond interactions between the dimer interface residues of the monomers in native and mutated forms of SOD1 in apo- and holo-states. The results obtained by this analysis reveal the fact that the loss of hydrogen bond interactions between the monomers of the dimer is responsible for the reduced stability of the apo- and holo-mutant forms of SOD1. The conformers with dimer interface residues in native and mutated protein obtained by the molecular dynamics simulation is subjected to quantum mechanical study using M052X/6-31G(d) level of theory. The charge transfer between N-H···O interactions in the dimer interface residues were studied. The weak interaction between the monomers of the dimer accounts for the reduced dimerization and enhanced deformation energy in the mutated SOD1 protein.

Protective effects of melatonin against 12C6+ beam irradiation-induced oxidative stress and DNA injury in the mouse brain

NASA Astrophysics Data System (ADS)

Wu, Z. H.; Zhang, H.; Wang, X. Y.; Yang, R.; Liu, B.; Liu, Y.; Zhao, W. P.; Feng, H. Y.; Xue, L. G.; Hao, J. F.; Niu, B. T.; Wang, Z. H.

2012-01-01

The purpose of this experiment was to estimate the protective effects of melatonin against radiation-induced brain damages in mice induced by heavy ion beams. Kun-Ming mice were randomly divided into five groups: normal control group, irradiation control group, and three different doses of melatonin (5, 10, and 20 mg/kg, i.p.) treated groups. Apart from the normal control group, the other four groups were exposed to whole-body 4.0 Gy carbon ion beam irradiation (approximately 0.5 Gy/min) after i.p. administration of normal saline or melatonin 1 h before irradiation. The oxidative redox status of brain tissue was assessed by measurement of malondiadehyde (MDA) levels, total superoxide dismutase (T-SOD), cytosolic superoxide dismutase (Cu/ZnSOD, SOD1) and mitochondrial superoxide dismutase (MnSOD, SOD2) activities at 8 h after irradiation. DNA damages were determined using the Comet assay and apoptosis and cell cycle distribution were detected by flow cytometric analyses. A dramatic dose-dependent decrease in MDA levels, tail moment, rates of tailing cells, and apoptosis, and a dose-dependent increase in T-SOD and SOD2 activities, in brain tissues in the melatonin-treated groups were detected compared with the irradiation only group. Furthermore, flow cytometric analysis demonstrated that the percentage of brain cells in the G0/G1 phase decreased significantly, while those in the S and G2/M stage increased dramatically, with mice pretreated with melatonin compared to the irradiation control group. These data indicate that melatonin has protective effects against irradiation-induced brain injury, and that its underlying protective mechanisms may relate to modulation of oxidative stress induced by heavy ionirradiation.

Responses of Reactive Oxygen Scavenging Enzymes, Proline and Malondialdehyde to Water Deficits among Six Secondary Successional Seral Species in Loess Plateau

PubMed Central

Du, Feng; Shi, Huijun; Zhang, Xingchang; Xu, Xuexuan

2014-01-01

Drought can impact local vegetation dynamics in a long term. In order to predict the possible successional pathway of local community under drought, the responses of some drought resistance indices of six successional seral species in the semi-arid Loss Hilly Region of China were illustrated and compared on three levels of soil water deficits along three growing months (7, 8 and 9). The results showed that: 1) the six species had significant differences in SOD, POD activities and MDA content. The rank correlations between SOD, POD activities and the successional niche positions of the six species were positive, and the correlation between MDA content and the niche positions was negative; 2) activities of SOD, CAT and POD, and content of proline and MDA had significant differences among the three months; 3) there existed significant interactions of SOD, CAT, POD activities and MDA content between months and species. With an exception, no interaction of proline was found. Proline in leaves had a general decline in reproductive month; 4) SOD, CAT, POD activities and proline content had negative correlations with MDA content. Among which, the correlation between SOD activity and MDA content was significant. The results implied that, in arid or semiarid region, the species at later successional stage tend to have strong drought resistance than those at early stage. Anti-drought indices can partially interpret the pathway of community succession in the drought impacted area. SOD activity is more distinct and important on the scope of protecting membrane damage through the scavenging of ROS on exposure to drought. PMID:24914928

Marked synergism between mutant SOD1 and glutamate transport inhibition in the induction of motor neuronal degeneration in spinal cord slice cultures.

PubMed

Yin, Hong Z; Weiss, John H

2012-04-11

Loss of astrocytic glutamate transport capacity in ALS spinal cord supports an excitotoxic contribution to motor neuron (MN) damage in the disease, and dominant gain of function mutations in Cu/Zn superoxide dismutase (SOD1) cause certain familial forms of ALS. We have used organotypic slice cultures from wild type and G93A SOD1 mutant rat spinal cords to examine interactions between excitotoxicity and the presence of mutant SOD1 in the induction of MN degeneration. Slice cultures were prepared from 1 week old pups, and after an additional week in vitro, some were exposed to either a low level (30 μM) of the glutamate uptake inhibitor, trans-pyrrolidine-2,4-dicarboxylic acid (PDC) for 3 weeks, or a higher level (50 μM) for 48 h, followed by histochemical labeling to assess MN injury. In wild type animals these exposures caused relatively little MN degeneration. Similarly, little MN degeneration was seen in slices from SOD1 mutant animals that were not exposed to PDC. However, addition of PDC to SOD1 mutant slices resulted in substantial MN injury, which was markedly attenuated by a Ca2+ permeable AMPA-type (Ca-AMPA) glutamate channel blocker, or by a nitric oxide synthase antagonist. These observations illustrate the utility of the organotypic culture model for the investigation of intracellular interactions underlying MN degeneration in ALS, and support the hypothesis that activation of Ca-AMPA channels on MNs provides a metabolic burden that synergizes with deleterious effects of mutant SOD1 in the induction of MN injury. Copyright © 2012 Elsevier B.V. All rights reserved.

Induction of steatohepatitis (NASH) with insulin resistance in wildtype B6 mice by a western-type diet containing soybean oil and cholesterol.

PubMed

Henkel, Janin; Coleman, Charles Dominic; Schraplau, Anne; Jӧhrens, Korinna; Weber, Daniela; Castro, José Pedro; Hugo, Martin; Schulz, Tim Julius; Krämer, Stephanie; Schürmann, Annette; Püschel, Gerhard Paul

2017-03-21

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are hepatic manifestations of the metabolic syndrome. Many currently used animal models of NAFLD/NASH lack clinical features of either NASH or metabolic syndrome such as hepatic inflammation and fibrosis (e.g. high-fat diets) or overweight and insulin resistance (e.g. methionine-choline-deficient diets) or they are based on monogenetic defects (e.g. ob/ob mice). In the current study, a western-type diet containing soybean oil with high n 6-PUFA and 0.75% cholesterol (SOD+Cho) induced steatosis, inflammation and fibrosis accompanied by hepatic lipid peroxidation and oxidative stress in livers of C57BL/6-mice which in addition showed increased weight gain and insulin resistance, thus displaying a phenotype closely resembling all clinical features of NASH in patients with metabolic syndrome. In striking contrast a soybean oil-containing western-type diet without cholesterol (SOD) induced only mild steatosis but neither hepatic inflammation nor fibrosis, weight gain or insulin resistance. Another high-fat diet mainly consisting of lard and supplemented with fructose in drinking water (LAD+Fru) resulted in more prominent weight gain, insulin resistance and hepatic steatosis than SOD+Cho but livers were devoid of inflammation and fibrosis. Although both LAD+Fru- and SOD+Cho-fed animals had high plasma cholesterol, liver cholesterol was elevated only in SOD+Cho animals. Cholesterol induced expression of chemotactic and inflammatory cytokines in cultured Kupffer cells and rendered hepatocytes more susceptible to apoptosis. Summarizing, dietary cholesterol in SOD+Cho diet may trigger hepatic inflammation and fibrosis. SOD+Cho-fed animals may be a useful disease model displaying many clinical features of patients with the metabolic syndrome and NASH.

Voronoi-based spatial analysis reveals selective interneuron changes in the cortex of FALS mice.

PubMed

Minciacchi, Diego; Kassa, Roman M; Del Tongo, Claudia; Mariotti, Raffaella; Bentivoglio, Marina

2009-01-01

The neurodegenerative disease amyotrophic lateral sclerosis affects lower motoneurons and corticospinal cells. Mice expressing human mutant superoxide dismutase (SOD)1 provide widely investigated models of the familial form of disease, but information on cortical changes in these mice is still limited. We here analyzed the spatial organization of interneurons characterized by parvalbumin immunoreactivity in the motor, somatosensory, and visual cortical areas of SOD1(G93A) mice. Cell number and sociological spatial behavior were assessed by digital charts of cell location in cortical samples, cell counts, and generation of two-dimensional Voronoi diagrams. In end-stage SOD1-mutant mice, an increase of parvalbumin-containing cortical interneurons was found in the motor and somatosensory areas (about 35% and 20%, respectively) with respect to wild-type littermates. Changes in cell spatial distribution, as documented by Voronoi-derived coefficients of variation, indicated increased tendency of parvalbumin cells to aggregate into clusters in the same areas of the SOD1-mutant cortex. Counts and coefficients of variation of parvalbumin cells in the visual cortex gave instead similar results in SOD1-mutant and wild-type mice. Analyses of motor and somatosensory areas in presymptomatic SOD1-mutant mice provided findings very similar to those obtained at end-stage, indicating early changes of interneurons in these cortical areas during the pathology. Altogether the data reveal in the SOD1-mutant mouse cortex an altered architectonic pattern of interneurons, which selectively affects areas involved in motor control. The findings, which can be interpreted as pathogenic factors or early disease-related adaptations, point to changes in the cortical regulation and modulation of the motor circuit during motoneuron disease.

Recombinant human manganese superoxide dismutase (rMnSOD): a positive effect on the immunohematological state of mice irradiated with protons

NASA Astrophysics Data System (ADS)

Ambesi-Impiombato, Francesco Saverio; Belov, Oleg; Bulinina, Taisia; Ivanov, Alexander; Mancini, Aldo; Borrelli, Antonella; Krasavin, Eugene A.

Protons represent the largest component of space radiation. In this regard screening of radioprotective drugs capable of increasing radioresistance of astronauts obligatory includes studying these compounds using proton radiation injury models. The recombinant human manganese superoxide dismutase (rMnSOD) had previously demonstrated its efficacy on an in vivo X-ray induced injury model, when multiple intraperitoneal treatments allowed the survival of mice irradiated with doses which were lethal for the control animals (Borrelli A et al. “A recombinant MnSOD is radioprotective for normal cells and radiosensitizing for tumor cells”. Free Radic Biol Med. 2009, 46, 110-6). Using the model of sublethal whole-body irradiation with protons available at Phasotron of Joint Institute for Nuclear Research (Dubna, Russia), we reconstruct the bone-marrow form of the acute radiation sickness to test the radioprotective effect of rMnSOD. Male (CBAxC57Bl6) F1 hybrid SPF mice weighting approximately 24 g were exposed to 171 MeV protons at the dose of 4 Gy. After irradiation, the sixfold daily subcutaneous treatment with rMnSOD has provided a statistically significant acceleration of the recovery of thymus and spleen mass and of the number of leukocytes in mice peripheral blood. In the control, untreated and irradiated mice, these positive effects were not observed even on day 7 after exposure. The number of karyocytes in bone marrow of irradiated mice has even exceeded its basal level in the control group 7 days after irradiation. The rMnSOD-treated group has thus demonstrated a significant hyper-restoration of this characteristic. In the presentation, several possibilities of using of rMnSOD in space medicine will be discussed, taking into account various biomedically relevant effects of this enzyme.

Senescence marker protein-30/superoxide dismutase 1 double knockout mice exhibit increased oxidative stress and hepatic steatosis

PubMed Central

Kondo, Yoshitaka; Masutomi, Hirofumi; Noda, Yoshihiro; Ozawa, Yusuke; Takahashi, Keita; Handa, Setsuko; Maruyama, Naoki; Shimizu, Takahiko; Ishigami, Akihito

2014-01-01

Superoxide dismutase 1 (SOD1) is an antioxidant enzyme that converts superoxide anion radicals into hydrogen peroxide and molecular oxygen. The senescence marker protein-30 (SMP30) is a gluconolactonase that functions as an antioxidant protein in mammals due to its involvement in ascorbic acid (AA) biosynthesis. SMP30 also participates in Ca2+ efflux by activating the calmodulin-dependent Ca2+-pump. To reveal the role of oxidative stress in lipid metabolism defects occurring in non-alcoholic fatty liver disease pathogenesis, we generated SMP30/SOD1-double knockout (SMP30/SOD1-DKO) mice and investigated their survival curves, plasma and hepatic lipid profiles, amounts of hepatic oxidative stress, and hepatic protein levels expressed by genes related to lipid metabolism. While SMP30/SOD1-DKO pups had no growth retardation by 14 days of age, they did have low plasma and hepatic AA levels. Thereafter, 39% and 53% of male and female pups died by 15–24 and 89 days of age, respectively. Compared to wild type, SMP30-KO and SOD1-KO mice, by 14 days SMP30/SOD1-DKO mice exhibited: (1) higher plasma levels of triglyceride and aspartate aminotransferase; (2) severe accumulation of hepatic triglyceride and total cholesterol; (3) higher levels of superoxide anion radicals and thiobarbituric acid reactive substances in livers; and (4) decreased mRNA and protein levels of Apolipoprotein B (ApoB) in livers – ApoB is an essential component of VLDL secretion. These results suggest that high levels of oxidative stress due to concomitant deficiency of SMP30 and/or AA, and SOD1 cause abnormal plasma lipid metabolism, hepatic lipid accumulation and premature death resulting from impaired VLDL secretion. PMID:25003023

Comparative Analyses of Cu-Zn Superoxide Dismutase (SOD1) and Thioredoxin Reductase (TrxR) at the mRNA Level between Apis mellifera L. and Apis cerana F. (Hymenoptera: Apidae) Under Stress Conditions.

PubMed

Koo, Hyun-Na; Lee, Soon-Gyu; Yun, Seung-Hwan; Kim, Hyun Kyung; Choi, Yong Soo; Kim, Gil-Hah

2016-01-01

This study compared stress-induced expression of Cu-Zn superoxide dismutase (SOD1) and thioredoxin reductase (TrxR) genes in the European honeybee Apis mellifera L. and Asian honeybee Apis cerana F. Expression of both SOD1 and TrxR rapidly increased up to 5 h after exposure to cold (4 °C) or heat (37 °C) treatment and then gradually decreased, with a stronger effect induced by cold stress in A. mellifera compared with A. cerana. Injection of stress-inducing substances (methyl viologen, [MV] and H2O2) also increased SOD1 and TrxR expression in both A. mellifera and A. cerana, and this effect was more pronounced with MV than H2O2. Additionally, we heterologously expressed the A. mellifera and A. cerana SOD1 and TrxR proteins in an Escherichia coli expression system, and detection by SDS-PAGE, confirmed by Western blotting using anti-His tag antibodies, revealed bands at 16 and 60 kDa, respectively. Our results show that the expression patterns of SOD1 and TrxR differ between A. mellifera and A. cerana under conditions of low or high temperature as well as oxidative stress. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

Role of oxidative stress in epithelial ovarian cancer in Egyptian patients.

PubMed

Ramadan, Asmaa; Hemida, Reda; Nowara, Ahmed; Eissa, Laila A; El-Gayar, Amal M

2017-05-01

Ovarian cancer has the highest mortality rate amongst all gynecologic malignancies. 90% of the cases are epithelial ovarian cancer (EOC). Ovarian cancer associated with reduction in the serum level of antioxidants super oxide dismutase (SOD) and glutathione peroxidase (GPX) and increasing in the serum level of Malondialdehyde (MDA). To find correlation between oxidative stress and epithelial ovarian cancer. In this cross-sectional study fifty-six female patients with EOC, twenty four female patients with benign ovarian tumors and ten healthy females were included in the current research study where serum level of SOD, GPX and MDA were measured. Levels of SOD and GPX were found to be significantly higher in benign group when compared with malignant group (P1<0.05). There was a significant negative association between malignancy and each of SOD and GPX (p<0.05). While there was a significant positive association between malignancy and MDA (p<0.05). There was a significant negative correlation between tumor stage and level of SOD and GPX (p<0.05). Moreover, there was a significance positive correlation between tumor stage and MDA (p< 0.05). Patients with epithelial ovarian cancer has decreased preoperative serum level of SOD and GPX antioxidants and increased level of MDA. These findings were associated with advanced tumor stage. The study confirmed the role of oxidative stress in development of epithelial ovarian cancer.

Decontamination of the digestive tract and oropharynx: hospital acquired infections after discharge from the intensive care unit.

PubMed

de Smet, Anne Marie G A; Hopmans, Titia E M; Minderhoud, Albertus L C; Blok, Hetty E M; Gossink-Franssen, Annelies; Bernards, Alexandra T; Bonten, Marc J M

2009-09-01

To determine the incidence rates of hospital acquired infections (HAI) during the first 14 days after ICU discharge after treatment during ICU-stay with Selective Decontamination of the Digestive tract (SDD), Selective Oropharyngeal Decontamination (SOD) or Standard Care (SC). Prospective observational study. ICUs in two tertiary care hospitals. Patients discharged from the ICU to the ward. None. Post-ICU incidences of HAI per 1,000 days at risk were 11.2, 12.9 and 8.3 for patients that had received SDD (n = 296), SOD (n = 286) or SC (n = 289) respectively in ICU, yielding relative risks, as compared to SC, of 1.49 (CI(95) 0.9-2.47) for SOD and 1.44 (CI(95) 0.87-2.39) for SDD. Incidences of surgical site infections (per 100 surgical procedures) were 4 after SC and 11.8 and 8 after SOD and SDD (p = 0.04). Among patients that succumbed in the hospital after ICU-stay (n = 58) eight (14%) had developed HAI after ICU discharge; 3 of 21 after SDD, 3 of 15 after SOD and 2 of 22 after SC. Incidences of HAI in general wards tended to be higher in patients that had received either SDD or SOD during ICU-stay, but it seems unlikely that these infections have an effect on hospital mortality rates.

Early Detection of Motor Dysfunction in the SOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis (ALS) Using Home Cage Running Wheels

PubMed Central

Bennett, Ellen J.; Mead, Richard J.; Azzouz, Mimoun; Shaw, Pamela J.; Grierson, Andrew J.

2014-01-01

The SOD1G93A mouse has been used since 1994 for preclinical testing in amyotrophic lateral sclerosis (ALS). Despite recent genetic advances in our understanding of ALS, transgenic mice expressing mutant SOD1 remain the best available, and most widely used, vertebrate model of the disease. We previously described an optimised and rapid approach for preclinical studies in the SOD1G93A mouse. Here we describe improvements to this approach using home cage running wheels to obtain daily measurements of motor function, with minimal intervention. We show that home cage running wheels detect reductions in motor function at a similar time to the rotarod test, and that the data obtained are less variable allowing the use of smaller groups of animals to obtain satisfactory results. This approach refines use of the SOD1G93A model, and reduces the number of animals undergoing procedures of substantial severity, two central principles of the 3Rs (replacement, reduction and refinement of animal use in research). The small group sizes and rapid timescales enable affordable large-scale therapeutic pre-screening in the SOD1G93A mouse, as well as rapid validation of published positive effects in a second laboratory, one of the major stumbling blocks in ALS preclinical therapy development. PMID:25268710

DJ-1 Is a Copper Chaperone Acting on SOD1 Activation*

PubMed Central

Girotto, Stefania; Cendron, Laura; Bisaglia, Marco; Tessari, Isabella; Mammi, Stefano; Zanotti, Giuseppe; Bubacco, Luigi

2014-01-01

Lack of oxidative stress control is a common and often prime feature observed in many neurodegenerative diseases. Both DJ-1 and SOD1, proteins involved in familial Parkinson disease and amyotrophic lateral sclerosis, respectively, play a protective role against oxidative stress. Impaired activity and modified expression of both proteins have been observed in different neurodegenerative diseases. A potential cooperative action of DJ-1 and SOD1 in the same oxidative stress response pathway may be suggested based on a copper-mediated interaction between the two proteins reported here. To investigate the mechanisms underlying the antioxidative function of DJ-1 in relation to SOD1 activity, we investigated the ability of DJ-1 to bind copper ions. We structurally characterized a novel copper binding site involving Cys-106, and we investigated, using different techniques, the kinetics of DJ-1 binding to copper ions. The copper transfer between the two proteins was also examined using both fluorescence spectroscopy and specific biochemical assays for SOD1 activity. The structural and functional analysis of the novel DJ-1 copper binding site led us to identify a putative role for DJ-1 as a copper chaperone. Alteration of the coordination geometry of the copper ion in DJ-1 may be correlated to the physiological role of the protein, to a potential failure in metal transfer to SOD1, and to successive implications in neurodegenerative etiopathogenesis. PMID:24567322

Aqueous two-phase system purification for superoxide dismutase induced by menadione from Phanerochaete chrysosporium.

PubMed

Kavakcıoğlu, Berna; Tongul, Burcu; Tarhan, Leman

2017-03-01

In the present work, the partitioning behavior of menadione-induced superoxide dismutase (SOD; EC 1.15.1.1), an antioxidant enzyme that has various applications in the medical and cosmetic industries, from the white rot fungus Phanerochaete chrysosporium has been characterized on different types of aqueous two-phase systems (ATPSs) (poly(ethylene glycol)/polypropylene glycol (PEG/PPG)-dextran, PEG-salt and PPG-salt). PEG-salt combinations were found most optimal systems for the purification of SOD. The best partition conditions were found using the PEG-3350 24% and K 2 HPO 4 5% (w/w) with pH 7.0 at 25 °C. The partition coefficient of total SOD activity and total protein concentration observed in this system were 0.17 and 6.65, respectively, with the recovery percentage as 78.90% in the bottom phase and 13.17% in the top phase. The highest purification fold for SOD from P. chrysosporium was found as 6.04 in the bottom phase of PEG 3350%24 - K 2 HPO 4 %5 (w/w) system with pH 7.0. SOD purified from P. chrysosporium was determined to be a homodimer in its native state with a molecular weight of 60  ± 4 kDa. Consequently, simple and only one step PEG-salt ATPS system was developed for SOD purification from P. chrysosporium.

Mutant SOD1-expressing astrocytes release toxic factors that trigger motoneuron death by inducing hyperexcitability

PubMed Central

Fritz, Elsa; Izaurieta, Pamela; Weiss, Alexandra; Mir, Franco R.; Rojas, Patricio; Gonzalez, David; Rojas, Fabiola; Brown, Robert H.; Madrid, Rodolfo

2013-01-01

Amyotrophic lateral sclerosis (ALS) is a devastating paralytic disorder caused by dysfunction and degeneration of motoneurons starting in adulthood. Recent studies using cell or animal models document that astrocytes expressing disease-causing mutations of human superoxide dismutase 1 (hSOD1) contribute to the pathogenesis of ALS by releasing a neurotoxic factor(s). Neither the mechanism by which this neurotoxic factor induces motoneuron death nor its cellular site of action has been elucidated. Here we show that acute exposure of primary wild-type spinal cord cultures to conditioned medium derived from astrocytes expressing mutant SOD1 (ACM-hSOD1G93A) increases persistent sodium inward currents (PCNa), repetitive firing, and intracellular calcium transients, leading to specific motoneuron death days later. In contrast to TTX, which paradoxically increased twofold the amplitude of calcium transients and killed motoneurons, reduction of hyperexcitability by other specific (mexiletine) and nonspecific (spermidine and riluzole) blockers of voltage-sensitive sodium (Nav) channels restored basal calcium transients and prevented motoneuron death induced by ACM-hSOD1G93A. These findings suggest that riluzole, the only FDA-approved drug with known benefits for ALS patients, acts by inhibiting hyperexcitability. Together, our data document that a critical element mediating the non-cell-autonomous toxicity of ACM-hSOD1G93A on motoneurons is increased excitability, an observation with direct implications for therapy of ALS. PMID:23486205

Sleep deprivation alters gene expression and antioxidant enzyme activity in mice splenocytes.

PubMed

Lungato, L; Marques, M S; Pereira, V G; Hix, S; Gazarini, M L; Tufik, S; D'Almeida, V

2013-03-01

Cellular defence against the formation of reactive oxygen species (ROS) involves a number of mechanisms in which antioxidant enzymes such as catalase (CAT) and superoxide dismutase (SOD) play an important role. The relation between sleep deprivation and oxidative stress has not yet been completely elucidated. Although some authors did not find evidence of this relationship, others found alterations in some oxidative stress markers in response to sleep deprivation. Thus, the objective of this study was to identify changes induced by sleep deprivation in the activity and gene expression of antioxidant enzymes in mice splenocytes, ideally corroborating a better understanding of the observed effects related to sleep deprivation, which could be triggered by oxidative imbalance. Splenocytes from mice sleep deprived for 72 h showed no significant difference in CAT and CuZnSOD gene expression compared with normal sleep mice. However, sleep-deprived mice did show higher MnSOD gene expression than the control group. Concerning enzymatic activity, CuZnSOD and MnSOD significantly increased after sleep deprivation, despite the expression in CuZnSOD remained unchanged. Moreover, CAT activity was significantly lower after sleep deprivation. The data suggest that the antioxidant system is triggered by sleep deprivation, which in turn could influence the splenocytes homoeostasis, thus interfering in physiological responses. © 2013 The Authors. Scandinavian Journal of Immunology © 2013 Blackwell Publishing Ltd.

Function of Oxygen Resistance Proteins in the Anaerobic, Sulfate-Reducing Bacterium Desulfovibrio vulgaris Hildenborough

PubMed Central

Fournier, Marjorie; Zhang, Yi; Wildschut, Janine D.; Dolla, Alain; Voordouw, Johanna K.; Schriemer, David C.; Voordouw, Gerrit

2003-01-01

Two mutant strains of Desulfovibrio vulgaris Hildenborough lacking either the sod gene for periplasmic superoxide dismutase or the rbr gene for rubrerythrin, a cytoplasmic hydrogen peroxide (H2O2) reductase, were constructed. Their resistance to oxidative stress was compared to that of the wild-type and of a sor mutant lacking the gene for the cytoplasmic superoxide reductase. The sor mutant was more sensitive to exposure to air or to internally or externally generated superoxide than was the sod mutant, which was in turn more sensitive than the wild-type strain. No obvious oxidative stress phenotype was found for the rbr mutant, indicating that H2O2 resistance may also be conferred by two other rbr genes in the D. vulgaris genome. Inhibition of Sod activity by azide and H2O2, but not by cyanide, indicated it to be an iron-containing Sod. The positions of Fe-Sod and Sor were mapped by two-dimensional gel electrophoresis (2DE). A strong decrease of Sor in continuously aerated cells, indicated by 2DE, may be a critical factor in causing cell death of D. vulgaris. Thus, Sor plays a key role in oxygen defense of D. vulgaris under fully aerobic conditions, when superoxide is generated mostly in the cytoplasm. Fe-Sod may be more important under microaerophilic conditions, when the periplasm contains oxygen-sensitive, superoxide-producing targets. PMID:12486042

The molecular mechanism of the termination of insect diapause, part 1: A timer protein, TIME-EA4, in the diapause eggs of the silkworm Bombyx mori is a metallo-glycoprotein.

PubMed

Isobe, Minoru; Kai, Hidenori; Kurahashi, Takuya; Suwan, Sathorn; Pitchayawasin-Thapphasaraphong, Suthasinee; Franz, Thomas; Tani, Naoki; Higashi, Kenichiro; Nishida, Hideo

2006-10-01

TIME-EA4 is an ATPase that measures time intervals, functioning as a diapause duration clock in diapause eggs of the silkworm, Bombyx mori. Characterization of the primary and higher structures of the TIME-EA4 would be desirable to clarify the mechanism by which the protein measures the time intervals. In our current studies, the whole sequence of TIME-EA4 has been established as that of a metallo-glycoprotein by combinational means involving peptide sequence analysis, nano-HPLC-ESI-Q-TOF-MS and MS/MS, and cDNA dictation. The amino acid sequence of TIME-EA4 showed 46-55 % homology with the reported proteins of the Cu,Zn-SOD (superoxide dismutase) family; in particular, the SOD active site (core domain) includes metal-binding amino acid ligands and a disulfide bond, and these structures are completely identical in Bombyx SOD, bovine SOD, and TIME-EA4 proteins. We found, however, that TIME-EA4 contains one more copper ion than other SODs, as was proven under neutral nondenaturing conditions. ESI mass spectrometry revealed that the timer function was not in the SOD core domain. In addition, TIME-EA4 has an attached sugar chain, which is indispensable to its functioning as a timer protein.

Overexpression of survival motor neuron improves neuromuscular function and motor neuron survival in mutant SOD1 mice.

PubMed

Turner, Bradley J; Alfazema, Neza; Sheean, Rebecca K; Sleigh, James N; Davies, Kay E; Horne, Malcolm K; Talbot, Kevin

2014-04-01

Spinal muscular atrophy results from diminished levels of survival motor neuron (SMN) protein in spinal motor neurons. Low levels of SMN also occur in models of amyotrophic lateral sclerosis (ALS) caused by mutant superoxide dismutase 1 (SOD1) and genetic reduction of SMN levels exacerbates the phenotype of transgenic SOD1(G93A) mice. Here, we demonstrate that SMN protein is significantly reduced in the spinal cords of patients with sporadic ALS. To test the potential of SMN as a modifier of ALS, we overexpressed SMN in 2 different strains of SOD1(G93A) mice. Neuronal overexpression of SMN significantly preserved locomotor function, rescued motor neurons, and attenuated astrogliosis in spinal cords of SOD1(G93A) mice. Despite this, survival was not prolonged, most likely resulting from SMN mislocalization and depletion of gems in motor neurons of symptomatic mice. Our results reveal that SMN upregulation slows locomotor deficit onset and motor neuron loss in this mouse model of ALS. However, disruption of SMN nuclear complexes by high levels of mutant SOD1, even in the presence of SMN overexpression, might limit its survival promoting effects in this specific mouse model. Studies in emerging mouse models of ALS are therefore warranted to further explore the potential of SMN as a modifier of ALS. Copyright © 2014 Elsevier Inc. All rights reserved.

Manganese Superoxide Dismutase in Cancer Prevention

PubMed Central

Robbins, Delira

2014-01-01

Abstract Significance: Cancer is the second leading cause of death in the United States. Considering the quality of life and treatment cost, the best way to fight against cancer is to prevent or suppress cancer development. Cancer is preventable as indicated by human papilloma virus (HPV) vaccination and tamoxifen/raloxifen treatment in breast cancer prevention. The activities of superoxide dismutases (SODs) are often lowered during early cancer development, making it a rational candidate for cancer prevention. Recent Advances: SOD liposome and mimetics have been shown to be effective in cancer prevention animal models. They've also passed safety tests during early phase clinical trials. Dietary supplement-based SOD cancer prevention provides another opportunity for antioxidant-based cancer prevention. New mechanistic studies have revealed that SOD inhibits not only oncogenic activity, but also subsequent metabolic shifts during early tumorigenesis. Critical Issues: Lack of sufficient animal model studies targeting specific cancers; and lack of clinical trials and support from pharmaceutical industries also hamper efforts in further advancing SOD-based cancer prevention. Future Directions: To educate and obtain support from our society that cancer is preventable. To combine SOD-based therapeutics with other cancer preventive agents to obtain synergistic effects. To formulate a dietary supplementation-based antioxidant approach for cancer prevention. Lastly, targeting specific populations who are prone to carcinogens, which can trigger oxidative stress as the mechanism of carcinogenesis. Antioxid. Redox Signal. 20, 1628–1645. PMID:23706068

Superoxide Dismutase

PubMed Central

Lee, Edward H.; Bennett, Jesse H.

1982-01-01

An experimental chemical N-[2-(2-oxo-1-imidazolidinyl)ethyl]-N′-phenylurea (EDU), is an effective protectant against acute and chronic foliar injury due to ozone (03) when sprayed on intact leaves or supplied to the plants through soil application. An 03-sensitive snap bean cultivar (Phaseolus vulgaris L. `Bush Blue Lake 290') was systemically treated with EDU (0, 25, 50, and 100 milligrams per 15-centimeter diameter pot) to determine if EDU-induced or activated protective oxyradical and peroxyl scavenging enzymes. EDU-enhanced tolerance to O3 injury always correlated with increases in superoxide dismutase (SOD) and catalase activities in the leaves. Peroxidase levels correlated more closely with foliar injury. Greater SOD levels in young leves compared to older leaves were associated with lower ozone sensitivities in these tissues. Polyacrylamide slab gel electrophoresis separations and specific determinations of SOD activity showed that EDU-treated plants possessed markedly greater SOD activity than non-treated plants. Tolerant plant tissues may have enhanced enzyme scavenging capabilities for the protection against toxic oxyradicals. Experimental confirmation for the oxyradical theory for O3 phytotoxicity and SOD involvement in the detoxification process are presented. Images PMID:16662420

SOD1 suppresses maternal hyperglycemia-increased iNOS expression and consequent nitrosative stress in diabetic embryopathy

PubMed Central

Weng, Hongbo; Li, Xuezheng; Reece, E. Albert; Yang, Peixin

2012-01-01

Objectives Hyperglycemia induces oxidative stress and increases inducible nitric oxide synthase (iNOS) expression. We hypothesized that oxidative stress is responsible for hyperglycemia-induced iNOS expression. Study Design iNOS-luciferase activities, nitrosylated protein, lipidperoxidation markers 4-HNE and MDA were determined in PYS-2 cells exposed to 5 mM glucose or high glucose (25 mM) with or without SOD1 (copper zinc superoxide dismutase 1) treatment. Levels of iNOS protein and mRNA, nitrosylated protein, and cleaved caspase-3 and -8 were assessed in wild-type embryos and SOD1 overexpressing embryos from non-diabetic and diabetic dams. Results SOD1 treatment diminished high glucose-induced oxidative stress, as evidenced by 4-HNE and MDA reductions, and it blocked high glucose-increased iNOS expression, iNOS-luciferase activities, and nitrosylated protein. in vivo SOD1 overexpression suppressed hyperglycemia-increased iNOS expression and nitrosylated protein, and it blocked caspase-3 and -8 cleavage. Conclusions We conclude that oxidative stress induces iNOS expression, nitrosative stress, and apoptosis in diabetic embryopathy. PMID:22425406

SOD1 suppresses maternal hyperglycemia-increased iNOS expression and consequent nitrosative stress in diabetic embryopathy.

PubMed

Weng, Hongbo; Li, Xuezheng; Reece, E Albert; Yang, Peixin

2012-05-01

Hyperglycemia induces oxidative stress and increases inducible nitric oxide synthase (iNOS) expression. We hypothesized that oxidative stress is responsible for hyperglycemia-induced iNOS expression. iNOS-luciferase activities, nitrosylated protein, and lipid peroxidation markers 4-hydroxynonenal and malondialdehyde were determined in parietal yolk sac-2 cells exposed to 5 mmol/L glucose or high glucose (25 mmol/L) with or without copper zinc superoxide dismutase 1 (SOD1) treatment. Levels of iNOS protein and messenger RNA, nitrosylated protein, and cleaved caspase-3 and -8 were assessed in wild-type embryos and SOD1-overexpressing embryos from nondiabetic and diabetic dams. SOD1 treatment diminished high glucose-induced oxidative stress, as evidenced by 4-hydroxynonenal and malondialdehyde reductions, and it blocked high glucose-increased iNOS expression, iNOS-luciferase activities, and nitrosylated protein. In vivo SOD1 overexpression suppressed hyperglycemia-increased iNOS expression and nitrosylated protein, and it blocked caspase-3 and -8 cleavage. We conclude that oxidative stress induces iNOS expression, nitrosative stress, and apoptosis in diabetic embryopathy. Copyright © 2012 Mosby, Inc. All rights reserved.

Neuron-specific regulation of superoxide dismutase amid pathogen-induced gut dysbiosis.

PubMed

Horspool, Alexander M; Chang, Howard C

2018-05-19

Superoxide dismutase, an enzyme that converts superoxide into less-toxic hydrogen peroxide and oxygen, has been shown to mediate behavioral response to pathogens. However, it remains largely unknown how superoxide dismutase is regulated in the nervous system amid pathogen-induced gut dysbiosis. Although there are five superoxide dismutases in C. elegans, our genetic analyses suggest that SOD-1 is the primary superoxide dismutase to mediate the pathogen avoidance response. When C. elegans are fed a P. aeruginosa diet, the lack of SOD-1 contributes to enhanced lethality. We found that guanylyl cyclases GCY-5 and GCY-22 and neuropeptide receptor NPR-1 act antagonistically to regulate SOD-1 expression in the gustatory neuron ASER. After C. elegans ingests a diet that contributes to high levels of oxidative stress, the temporal regulation of SOD-1 and the SOD-1-dependent response in the gustatory system demonstrates a sophisticated mechanism to fine-tune behavioral plasticity. Our results may provide the initial glimpse of a strategy by which a multicellular organism copes with oxidative stress amid gut dysbiosis. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

The Antitumor Effect of Single-domain Antibodies Directed Towards Membrane-associated Catalase and Superoxide Dismutase.

PubMed

Bauer, Georg; Motz, Manfred

2016-11-01

Neutralizing single-domain antibodies directed towards catalase or superoxide dismutase (SOD) caused efficient reactivation of intercellular reactive oxygen species/reactive nitrogen species (ROS/RNS)-dependent apoptosis-inducing signaling specifically in human tumor cells. Single-domain antibodies targeted tumor cell-specific membrane-associated SOD and catalase, but not the corresponding intracellular enzymes. They were shown to be about 200-fold more effective than corresponding classical recombinant antigen-binding fragments and more than four log steps more efficient than monoclonal antibodies. Combined addition of single-domain antibodies against catalase and SOD caused a remarkable synergistic effect. Proof-of-concept experiments in immunocompromised mice using human tumor xenografts and single-domain antibodies directed towards SOD showed an inhibition of tumor growth. Neutralizing single-domain antibodies directed to catalase and SOD also caused a very strong synergistic effect with the established chemotherapeutic agent taxol, indicating an overlap of signaling pathways. This effect might also be useful in order to avoid unwanted side-effects and to drastically lower the costs for taxol-based therapy. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Spontaneous abortion and functional polymorphism (Val16Ala) in the manganese SOD gene.

PubMed

Eskafi Sabet, E; Salehi, Z; Khodayari, S; Sabouhi Zarafshan, S; Zahiri, Z

2015-02-01

Spontaneous abortion is the most common complication of early pregnancy. Genetic factors have been hypothesised to play a role in spontaneous abortion. Since it is possible that the balance of oxidants and antioxidants can be affected by different genetic variants, gene polymorphisms have been proposed as a susceptibility factor that increases the chance of miscarriage. Manganese superoxide dismutase is an important antioxidant enzyme encoded by manganese superoxide dismutase (MnSOD) gene. The aim of this experiment was to assess whether Val16Ala polymorphism of MnSOD gene is associated with miscarriage in northern Iran. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for genotyping. Statistical analyses were conducted using the χ(2)-test. The genetic distributions did not differ significantly between cases and controls, however slightly more Val/Val genotypes were found among the patients compared with control subjects (p = 0.059). No correlation was observed between susceptibility to abortion and MnSOD Val16Ala polymorphism. Larger population-based studies are needed for clarifying the relationship between abortion and MnSOD genotypes.

[Activity of antioxidative enzymes and concentration of malondialdehyde as oxidative status markers in women with non-autoimmunological subclinical hyperthyroidism].

PubMed

Rybus-Kalinowska, Barbara; Zwirska-Korczala, Krystyna; Kalinowski, Mariusz; Kukla, Michał; Birkner, Ewa; Jochem, Jerzy

2009-01-01

The recent investigations point out the significant role of oxidative stress in the development of thyroid gland disease. The present study was designed to investigate the variation of oxidative stae in women with non-autoimmunological subclinical hyperthyroidism. The study was conducted on 20 females with non-autoimmunological subclinical hyperthyroidism and 15 healthy women. Manganase-containing superoxide dismutase (Mn-SOD) and extracellular superoxide dismutase (EC-SOD) plasma activity, and malondialdehyde (MDA) plasma concentration were measured. EC-SOD plasma activity was significantly higher in women with subclinical hyperthyroidism when compared with the control group (13.3 +/- 2.1 vs. 10.9 +/- 1.4 NU/ml; p < 0.05), unlike Mn-SOD (4.2 +/- 0.5 vs. 4.0 +/- 1.0 NU/ml). MDA plasma concentration increased significantly in women with subclinical hyperthyroidism (3.5 +/- 1.2 vs. 2.0 +/- 0.6 micromol/l; p < 0.05). The increased EC-SOD plasma activity may reflect disturbances of oxidative state in subclinical hyperthyroidism. Parallel increase of MDA plasma concentration may indicate enhancement of lipid peroxidationin in patients with subclinical hyperthyroidism.

The Cu-Zn superoxide dismutase (SOD1) inhibits ERK phosphorylation by muscarinic receptor modulation in rat pituitary GH3 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Secondo, Agnese; De Mizio, Mariarosaria; Zirpoli, Laura

The Cu-Zn superoxide dismutase (SOD1) belongs to a family of isoenzymes that are able to dismutate the oxygen superoxide in hydrogen peroxide and molecular oxygen. This enzyme is secreted by many cellular lines and it is also released trough a calcium-dependent depolarization mechanism involving SNARE protein SNAP 25. Using rat pituitary GH3 cells that express muscarinic receptors we found that SOD1 inhibits P-ERK1/2 pathway trough an interaction with muscarinic M1 receptor. This effect is strengthened by oxotremorine, a muscarinic M agonist and partially reverted by pyrenzepine, an antagonist of M1 receptor; moreover this effect is independent from increased intracellular calciummore » concentration induced by SOD1. Finally, P-ERK1/2 inhibition was accompanied by the reduction of GH3 cell proliferation. These data indicate that SOD1 beside the well studied antioxidant properties can be considered as a neuromodulator able to affect mitogen-activated protein kinase in rat pituitary cells trough a M1 muscarinic receptor.« less

Effect of Trasina, an Ayurvedic herbal formulation, on pancreatic islet superoxide dismutase activity in hyperglycaemic rats.

PubMed

Bhattacharya, S K; Satyan, K S; Chakrabarti, A

1997-03-01

Diabetes mellitus was induced in male CF strain rats by streptozotocin (STZ) and hyperglycaemia and superoxide dismutase (SOD) activity of pancreatic islet cells was assessed on days 7, 14, 21 and 28. STZ induced significant hyperglycaemia and a concomitant decrease in islet cell SOD activity. Transina (TR), an Ayurvedic herbal formulation comprising of Withania somnifera, Tinospora cordifolia, Eclipta alba, Ocimum sanctum, Picrorrhiza kurroa and shilajit, had little per se effect on blood sugar concentrations and islet SOD activity in euglycaemic rats, in the doses of 100 and 200 mg/kg, p.o. administered once daily for 28 days. However, these doses of TR induced a dose- related decrease in STZ hyperglycaemia and attenuation of STZ induced decrease in islet SOD activity. The results indicate that the earlier reported anti-hyperglycaemic effect of TR may be due to pancreatic islet free radical scavenging activity, the hyperglycaemic activity of STZ being the consequence of decrease in islet SOD activity leading to the accumulation of degenerative oxidative free radicals in islet beta-cells.

The association of sphenoidal encephalocele and right anophthalmia with septo-optic dysplasia: a case report.

PubMed

Erol, Fatih Serhat; Ucler, Necati; Kaplan, Metin; Yilmaz, Ilhan

2012-01-01

Septo-optic dysplasia (SOD) is an extremely rare congenital anomaly, characterized with optic nerve hypoplasia and absence of septum pellucidum and/or pituitary dysfunction. In addition to classical findings of SOD, we report for the first time an 11-year-old boy, with encephalocele extending to the right sphenoidal sinus, right anophthalmia and normal pituitary functions. Despite all the major anomalies, the patient's presenting symptoms were very few and during the 11-year period the SDO had caused no complaints in our case. These findings show that the SOD course may be fairly benign. No neurological problem was encountered in the patient's follow-up, except headache. We believe that SOD should be kept in mind because of its rarity and the severity of its combined pathologies.

Extraction of superoxide dismutase, catalase, and carbonic anhydrase from stroma-free red blood cell hemolysate for the preparation of the nanobiotechnological complex of polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase.

PubMed

Guo, C; Gynn, M; Chang, T M S

2015-06-01

We report a novel method to simultaneously extract superoxide dismutase (SOD), catalase (CAT), and carbonic anhydrase (CA) from the same sample of red blood cells (RBCs). This avoids the need to use expensive commercial enzymes, thus enabling a cost-effective process for large-scale production of a nanobiotechnological polyHb-SOD-CAT-CA complex, with enhancement of all three red blood cell functions. An optimal concentration of phosphate buffer for ethanol-chloroform treatment results in good recovery of CAT, SOD, and CA after extraction. Different concentrations of the enzymes can be used to enhance the activity of polyHb-SOD-CAT-CA to 2, 4, or 6 times that of RBC.

Data set for phylogenetic tree and RAMPAGE Ramachandran plot analysis of SODs in Gossypium raimondii and G. arboreum.

PubMed

Wang, Wei; Xia, Minxuan; Chen, Jie; Deng, Fenni; Yuan, Rui; Zhang, Xiaopei; Shen, Fafu

2016-12-01

The data presented in this paper is supporting the research article "Genome-Wide Analysis of Superoxide Dismutase Gene Family in Gossypium raimondii and G. arboreum" [1]. In this data article, we present phylogenetic tree showing dichotomy with two different clusters of SODs inferred by the Bayesian method of MrBayes (version 3.2.4), "Bayesian phylogenetic inference under mixed models" [2], Ramachandran plots of G. raimondii and G. arboreum SODs, the protein sequence used to generate 3D sructure of proteins and the template accession via SWISS-MODEL server, "SWISS-MODEL: modelling protein tertiary and quaternary structure using evolutionary information." [3] and motif sequences of SODs identified by InterProScan (version 4.8) with the Pfam database, "Pfam: the protein families database" [4].

Tryptophan 32 potentiates aggregation and cytotoxicity of a copper/zinc superoxide dismutase mutant associated with familial amyotrophic lateral sclerosis.

PubMed

Taylor, David M; Gibbs, Bernard F; Kabashi, Edor; Minotti, Sandra; Durham, Heather D; Agar, Jeffrey N

2007-06-01

One familial form of the neurodegenerative disease, amyotrophic lateral sclerosis, is caused by gain-of-function mutations in the gene encoding copper/zinc superoxide dismutase (SOD-1). This study provides in vivo evidence that normally occurring oxidative modification to SOD-1 promotes aggregation and toxicity of mutant proteins. The oxidation of Trp-32 was identified as a normal modification being present in both wild-type enzyme and SOD-1 with the disease-causing mutation, G93A, isolated from erythrocytes. Mutating Trp-32 to a residue with a slower rate of oxidative modification, phenylalanine, decreased both the cytotoxicity of mutant SOD-1 and its propensity to form cytoplasmic inclusions in motor neurons of dissociated mouse spinal cord cultures.

Microencapsulation of superoxide dismutase into poly(epsilon-caprolactone) microparticles by reverse micelle solvent evaporation.

PubMed

Youan, Bi-Botti Célestin

2003-01-01

The aim of this work was to encapsulate superoxide dismutase (SOD) in poly(epsilon-caprolactone) (PCL) microparticles by reverse micelle solvent evaporation. The concentration of PCL, the hydrophile-lipophile balance (HLB), and concentration of the sucrose ester used as surfactant in the organic phase were investigated as formulation variables. Relatively higher encapsulation efficiency (approximately 48%) and retained enzymatic activity (>90%) were obtained with microparticle formulation made from the 20% (w/v) PCL and 0.05% (w/v) sucrose ester of HLB = 6. This formulation allowed the in vitro release of SOD for at least 72 hr. These results showed that reverse micelle solvent evaporation can be used to efficiently encapsulate SOD in PCL microparticles. Such formulations may improve the bioavailability of SOD.

Preferential motor unit loss in the SOD1G93A transgenic mouse model of amyotrophic lateral sclerosis

PubMed Central

Hegedus, J; Putman, C T; Tyreman, N; Gordon, T

2008-01-01

The present study investigated motor unit (MU) loss in a murine model of familial amyotrophic lateral sclerosis (ALS). The fast-twitch tibialis anterior (TA) and medial gastrocnemius (MG) muscles of transgenic SOD1G93A and SOD1WT mice were studied during the presymptomatic phase of disease progression at 60 days of age. Whole muscle maximum isometric twitch and tetanic forces were 80% lower (P < 0.01) in the TA muscles of SOD1G93A compared to SOD1WT mice. Enumeration of total MU numbers within TA muscles showed a 60% reduction (P < 0.01) within SOD1G93A mice (38 ± 7) compared with SOD1WT controls (95 ± 12); this was attributed to a lower proportion of the most forceful fast-fatigable (FF) MU in SOD1G93A mice, as seen by a significant (P < 0.01) leftward shift in the cumulative frequency histogram of single MU forces. Similar patterns of MU loss and corresponding decreases in isometric twitch force were observed in the MG. Immunocytochemical analyses of the entire cross-sectional area (CSA) of serial sections of TA muscles stained with anti-neural cell adhesion molecule (NCAM) and various monoclonal antibodies for myosin heavy chain (MHC) isoforms showed respective 65% (P < 0.01) and 28% (P < 0.05) decreases in the number of innervated IIB and IID/X muscle fibres in SOD1G93A, which paralleled the 60% decrease (P < 0.01) in the force generating capacity of individual fibres. The loss of fast MUs was partially compensated by activity-dependent fast-to-slower fibre type transitions, as determined by increases (P < 0.04) in the CSA and proportion of IIA fibres (from 4% to 14%) and IID/X fibres (from 31% to 39%), and decreases (P < 0.001) in the CSA and proportion of type IIB fibres (from 65% to 44%). We conclude that preferential loss of IIB fibres is incomplete at 60 days of age, and is consistent with a selective albeit gradual loss of FF MUs that is not fully compensated by sprouting of the remaining motoneurons that innervate type IIA or IID/X muscle fibres. Our findings indicate that disease progression in fast-twitch muscles of SOD1G93A mice involves parallel processes: (1) gradual selective motor axon die-back of the FF motor units that contain large type IIB muscle fibres, and of fatigue-intermediate motor units that innervate type IID/X muscle fibres, and (2) activity-dependent conversion of motor units to those innervated by smaller motor axons innervating type IIA fatigue-resistant muscle fibres. PMID:18467368

Environmental Assessment: Construct Airfield Lighting Vault and Demolish Building 531 at Grand Forks Air Force Base

DTIC Science & Technology

2007-08-01

The backfill material shall be free of bentonite, trash, frozen or organic material including lignites, humus , sod, grass, roots or other...organic material including lignites, humus , sod, grass, roots or other vegetation. The backfill material shall not be of a size greater than 3 inches, may...lignites, humus , sod, grass, roots or other vegetation. The backfill material shall not be of a size greater than 3 inches, may not contain more than 12

Inhibitors of SOD1 Interaction as an Approach to Slow the Progressive Spread of ALS Symptoms

DTIC Science & Technology

2016-07-01

luciferase enzyme can be split into 2 halves. These 2 halves can be forced to reconstitute an active enzyme if they are brought together by some...force. In our assay, this force is the normal interaction that occurs when 2 individual SOD1 proteins come together to form a normal active enzyme ...Using recombinant DNA, we create fusion proteins of SOD1 and each half of the luciferase enzyme . In the past year, we have characterized and optimized

75 FR 26754 - Pesticide Products; Registration Applications

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-12

... Use/Terrestrial Non- food Crops: Landscape ornamentals and turf grass (including sod farms) and...) and turf grass (including sod farms) Docket ID Number: EPA-HQ-OPP-2010-0349. New Active Ingredient...

Molecular Basis for Antioxidant Enzymes in Mediating Copper Detoxification in the Nematode Caenorhabditis elegans

PubMed Central

Song, Shaojuan; Zhang, Xueyao; Wu, Haihua; Han, Yan; Zhang, Jianzhen; Ma, Enbo; Guo, Yaping

2014-01-01

Antioxidant enzymes play a major role in defending against oxidative damage by copper. However, few studies have been performed to determine which antioxidant enzymes respond to and are necessary for copper detoxification. In this study, we examined both the activities and mRNA levels of SOD, CAT, and GPX under excessive copper stress in Caenorhabditis elegans, which is a powerful model for toxicity studies. Then, taking advantage of the genetics of this model, we assessed the lethal concentration (LC50) values of copper for related mutant strains. The results showed that the SOD, CAT, and GPX activities were significantly greater in treated groups than in controls. The mRNA levels of sod-3, sod-5, ctl-1, ctl-2, and almost all gpx genes were also significantly greater in treated groups than in controls. Among tested mutants, the sod-5, ctl-1, gpx-3, gpx-4, and gpx-6 variants exhibited hypersensitivity to copper. The strains with SOD or CAT over expression were reduced sensitive to copper. Mutations in daf-2 and age-1, which are involved in the insulin/insulin-like growth factor-1 signaling pathway, result in reduced sensitivity to stress. Here, we showed that LC50 values for copper in daf-2 and age-1 mutants were significantly greater than in N2 worms. However, the LC50 values in daf-16;daf-2 and daf-16;age-1 mutants were significantly reduced than in daf-2 and age-1 mutants, implying that reduced copper sensitivity is influenced by DAF-16-related functioning. SOD, CAT, and GPX activities and the mRNA levels of the associated copper responsive genes were significantly increased in daf-2 and age-1 mutants compared to N2. Additionally, the activities of SOD, CAT, and GPX were greater in these mutants than in N2 when treated with copper. Our results not only support the theory that antioxidant enzymes play an important role in copper detoxification but also identify the response and the genes involved in these processes. PMID:25243607

Reactive oxygen species trigger motoneuron death in non-cell-autonomous models of ALS through activation of c-Abl signaling

PubMed Central

Rojas, Fabiola; Gonzalez, David; Cortes, Nicole; Ampuero, Estibaliz; Hernández, Diego E.; Fritz, Elsa; Abarzua, Sebastián; Martinez, Alexis; Elorza, Alvaro A.; Alvarez, Alejandra; Court, Felipe; van Zundert, Brigitte

2015-01-01

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease in which pathogenesis and death of motor neurons are triggered by non-cell-autonomous mechanisms. We showed earlier that exposing primary rat spinal cord cultures to conditioned media derived from primary mouse astrocyte conditioned media (ACM) that express human SOD1G93A (ACM-hSOD1G93A) quickly enhances Nav channel-mediated excitability and calcium influx, generates intracellular reactive oxygen species (ROS), and leads to death of motoneurons within days. Here we examined the role of mitochondrial structure and physiology and of the activation of c-Abl, a tyrosine kinase that induces apoptosis. We show that ACM-hSOD1G93A, but not ACM-hSOD1WT, increases c-Abl activity in motoneurons, interneurons and glial cells, starting at 60 min; the c-Abl inhibitor STI571 (imatinib) prevents this ACM-hSOD1G93A-mediated motoneuron death. Interestingly, similar results were obtained with ACM derived from astrocytes expressing SOD1G86R or TDP43A315T. We further find that co-application of ACM-SOD1G93A with blockers of Nav channels (spermidine, mexiletine, or riluzole) or anti-oxidants (Trolox, esculetin, or tiron) effectively prevent c-Abl activation and motoneuron death. In addition, ACM-SOD1G93A induces alterations in the morphology of neuronal mitochondria that are related with their membrane depolarization. Finally, we find that blocking the opening of the mitochondrial permeability transition pore with cyclosporine A, or inhibiting mitochondrial calcium uptake with Ru360, reduces ROS production and c-Abl activation. Together, our data point to a sequence of events in which a toxic factor(s) released by ALS-expressing astrocytes rapidly induces hyper-excitability, which in turn increases calcium influx and affects mitochondrial structure and physiology. ROS production, mediated at least in part through mitochondrial alterations, trigger c-Abl signaling and lead to motoneuron death. PMID:26106294

Time- and dose-dependent differential regulation of copper-zinc superoxide dismutase and manganese superoxide dismutase enzymatic activity and mRNA level by vitamin E in rat blood cells.

PubMed

Hajiani, Maliheh; Razi, Farideh; Golestani, Aboualfazl; Frouzandeh, Mehdi; Owji, Ali Akbar; Khaghani, Shahnaz; Ghannadian, Naghmeh; Shariftabrizi, Ahmad; Pasalar, Parvin

2012-01-01

Vitamin E is the most important lipid-soluble antioxidant. Recently, it has been proposed as a gene regulator, and its gene modulation effects have been observed at different levels of gene expression and cell signaling. This study was performed to investigate the effects of vitamin E on the activity and expression of the most important endogenous antioxidant enzyme, superoxide dismutase (SOD), in rat plasma. Twenty-eight male Sprauge-Dawley rats were divided into four groups: control group and three dosing groups. The control group received the vehicle (liquid paraffin), and the dosing groups received twice-weekly intraperitoneal injections of 10, 30, and 100 mg/kg of vitamin E ((±)-α-Tocopherol) for 6 weeks. Quantitative real-time reverse transcription-polymerase chain reaction and enzyme assays were used to assess the levels of Cu/Zn-SOD and Mn-SOD mRNA and enzyme activity levels in blood cells at 0, 2, 4, and 6 weeks following vitamin E administration. Catalase enzyme activity and total antioxidant capacity were also assessed in plasma at the same time intervals. Mn-SOD activity was significantly increased in the 100 and 30 mg/kg dosing groups after 4 and 6 weeks, with corresponding significant increase in their mRNA levels. Cu/Zn-SOD activity was not significantly changed in response to vitamin E administration at any time points, whereas Cu/Zn-SOD mRNA levels were significantly increased after longer time points with high doses (30 and 100 mg/kg) of vitamin E. Catalase enzyme activity was transiently but significantly increased after 4 weeks of vitamin E treatment in 30 and 100 mg/kg dosing groups. Total antioxidant status was significantly increased after 4 and 6 weeks in the 100 mg/kg dosing group. Only the chronic administration of higher doses of alpha-tocopherol is associated with the increased activity and expression of Mn-SOD in rats. Cu/Zn-SOD activity and expression does not dramatically change in response to vitamin E.

Levels of selected oxidative stress markers in the vitreous and serum of diabetic retinopathy patients.

PubMed

Brzović-Šarić, Vlatka; Landeka, Irena; Šarić, Borna; Barberić, Monika; Andrijašević, Lidija; Cerovski, Branimir; Oršolić, Nada; Đikić, Domagoj

2015-01-01

In diabetes, an impaired antioxidant defense system contributes to the development of diabetic retinopathy. The main objective of this paper was to find correlations of oxidative stress parameters within and between the vitreous and serum in patients with type 2 diabetes who had developed proliferative diabetic retinopathy. The study included and compared two groups of patients who underwent vitrectomy: 37 patients with type 2 diabetes and proliferative retinopathy (PDR), and 50 patients with non-diabetic eye disorders (NDED). Vascular endothelial growth factor (VEGF), advanced oxidized protein product (AOPP), and oxidative stress markers (direct lipid hydroperoxidation (LPO), malondialdehyde (MDA), total superoxide dismutase (SOD), and glutathione (GSH)) were measured in the vitreous and serum of both groups and correlated with one another, between humoral compartments and with gender, age, and serum glucose levels. In the vitreous of PDR patients, VEGF, LPO, and MDA (p<0.05) were increased and SOD values were slightly lowered (p<0.05) than in NDED patients. Vitreous AOPP and GSH showed no differences between the groups. In the serum, AOPP, MDA, and SOD were increased (p<0.05) and VEGF was slightly increased (p<0.05) in the PDR group compared to NDED. With regard to gender, similar changes were recorded for both groups, except for the lower serum MDA in males than females in the NDED group. Advanced age showed no significant effect on changes of measured parameters in the vitreous. In the serum, VEGF was positively correlated (p<0.05) and MDA and SOD negatively correlated (p<0.05) with increasing age. Among measured parameters within and between the vitreous and serum, several correlative links occurred in the PDR group that were not present in the NDED group. The most prominent correlation changes were between serum LPO and vitreal LPO, serum SOD and vitreal LPO, serum LPO and serum SOD, and vitreal VEGF and serum SOD. Among the selected oxidative stress markers, SOD and LPO were highly correlative in both the vitreous and serum in PDR compared to patients without metabolic disorders. Their correlations suggested that monitoring their mutual alterations might be informative during PDR development and should be considered in further research.

The combined transduction of copper, zinc-superoxide dismutase and catalase mediated by cell-penetrating peptide, PEP-1, to protect myocardium from ischemia-reperfusion injury.

PubMed

Huang, Guang-Qing; Wang, Jia-Ning; Tang, Jun-Ming; Zhang, Lei; Zheng, Fei; Yang, Jian-Ye; Guo, Ling-Yun; Kong, Xia; Huang, Yong-Zhang; Liu, Yong; Chen, Shi-You

2011-05-21

Our previous studies indicate that either PEP-1-superoxide dismutase 1 (SOD1) or PEP-1-catalase (CAT) fusion proteins protects myocardium from ischemia-reperfusion-induced injury in rats. The aim of this study is to explore whether combined use of PEP-1-SOD1 and PEP-1-CAT enhances their protective effects. SOD1, PEP-1-SOD1, CAT or PEP-1-CAT fusion proteins were prepared and purified by genetic engineering. In vitro and in vivo effects of these proteins on cell apoptosis and the protection of myocardium after ischemia-reperfusion injury were measured. Embryo cardiac myocyte H9c2 cells were used for the in vitro studies. In vitro cellular injury was determined by the expression of lactate dehydrogenase (LDH). Cell apoptosis was quantitatively assessed with Annexin V and PI double staining by Flow cytometry. In vivo, rat left anterior descending coronary artery (LAD) was ligated for one hour followed by two hours of reperfusion. Hemodynamics was then measured. Myocardial infarct size was evaluated by TTC staining. Serum levels of myocardial markers, creatine kinase-MB (CK-MB) and cTnT were quantified by ELISA. Bcl-2 and Bax expression in left ventricle myocardium were analyzed by western blot. In vitro, PEP-1-SOD1 or PEP-1-CAT inhibited LDH release and apoptosis rate of H9c2 cells. Combined transduction of PEP-1-SOD1 and PEP-1-CAT, however, further reduced the LDH level and apoptosis rate. In vivo, combined usage of PEP-1-SOD1 and PEP-1-CAT produced a greater effect than individual proteins on the reduction of CK-MB, cTnT, apoptosis rate, lipoxidation end product malondialdehyde, and the infarct size of myocardium. Functionally, the combination of these two proteins further increased left ventricle systolic pressure, but decreased left ventricle end-diastolic pressure. This study provided a basis for the treatment or prevention of myocardial ischemia-reperfusion injury with the combined usage of PEP-1-SOD1 and PEP-1-CAT fusion proteins.

Septo-Optic Dysplasia

MedlinePlus

... children with SOD have normal intelligence, others have learning disabilities. Most, however, are developmentally delayed due to vision ... children with SOD have normal intelligence, others have learning disabilities. Most, however, are developmentally delayed due to vision ...

7 CFR 1437.309 - Turfgrass sod.

Code of Federal Regulations, 2011 CFR

2011-01-01

... stratum of soil bound by mature grass and plant roots into a thick mat produced in commercial quantities for sale. (b) Specific species, types or varieties of grass intended for turfgrass sod will be...

7 CFR 1437.309 - Turfgrass sod.

Code of Federal Regulations, 2010 CFR

2010-01-01

... stratum of soil bound by mature grass and plant roots into a thick mat produced in commercial quantities for sale. (b) Specific species, types or varieties of grass intended for turfgrass sod will be...

Immobilization of Superoxide Dismutase on Polyelectrolyte-Functionalized Titania Nanosheets.

PubMed

Rouster, Paul; Pavlovic, Marko; Szilagyi, Istvan

2018-02-16

The superoxide dismutase (SOD) enzyme was successfully immobilized on titania nanosheets (TNS) functionalized with the poly(diallyldimethylammonium chloride) (PDADMAC) polyelectrolyte. The TNS-PDADMAC solid support was prepared by hydrothermal synthesis followed by self-assembled polyelectrolyte layer formation. It was found that SOD strongly adsorbed onto oppositely charged TNS-PDADMAC through electrostatic and hydrophobic interactions. The TNS-PDADMAC-SOD material was characterized by light scattering and microscopy techniques. Colloidal stability studies revealed that the obtained nanocomposites possessed good resistance against salt-induced aggregation in aqueous suspensions. The enzyme kept its functional integrity upon immobilization; therefore, TNS-PDADMAC-SOD showed excellent superoxide radical anion scavenging activity. The developed system is a promising candidate for applications in which suspensions of antioxidant activity are required in the manufacturing processes. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Free radicals of oxygen and superoxide dismutase. Biological and medical aspects].

PubMed

Monte, M; Sacerdote de Lustig, E

1994-01-01

Oxygen free radicals (OFR) are very reactive and unstable metabolites capable of altering important biomolecules including proteins, lipids and nucleic acids. OFR are regulated by enzymes such as superoxide dismutases (SOD), catalase, glutation peroxidase and by molecules such as vitamins E, A, C, and K, selenio, cystein and other compounds. Increased OFR levels due to an overproduction of these metabolites or to a failure in the control system, induce cellular and tissue injuries that could lead to diseases such as atherosclerosis, arthritis, fibrosis, lung and heart injuries, neurological disorders and cancer. In this article we consider the use of SOD as therapeutic agents both in human and experimental models. We also refer to the administration of SOD as a protective factor against secondary injuries during radiotherapy and to the determination of SOD as a tumor marker.

Copper binding by tetrathiomolybdate attenuates angiogenesis and tumor cell proliferation through the inhibition of superoxide dismutase 1.

PubMed

Juarez, Jose C; Betancourt, Oscar; Pirie-Shepherd, Steven R; Guan, Xiaojun; Price, Melissa L; Shaw, David E; Mazar, Andrew P; Doñate, Fernando

2006-08-15

A second-generation tetrathiomolybdate analogue (ATN-224; choline tetrathiomolybdate), which selectively binds copper with high affinity, is currently completing two phase I clinical trials in patients with advanced solid and advanced hematologic malignancies. However, there is very little information about the mechanism of action of ATN-224 at the molecular level. The effects of ATN-224 on endothelial and tumor cell growth were evaluated in cell culture experiments in vitro. The antiangiogenic activity of ATN-224 was investigated using the Matrigel plug model of angiogenesis. ATN-224 inhibits superoxide dismutase 1 (SOD1) in tumor and endothelial cells. The inhibition of SOD1 leads to inhibition of endothelial cell proliferation in vitro and attenuation of angiogenesis in vivo. The inhibition of SOD1 activity in endothelial cells is dose and time dependent and leads to an increase in the steady-state levels of superoxide anions, resulting in the inhibition of extracellular signal-regulated kinase phosphorylation without apparent induction of apoptosis. In contrast, the inhibition of SOD1 in tumor cells leads to the induction of apoptosis. The effects of ATN-224 on endothelial and tumor cells could be substantially reversed using Mn(III)tetrakis(4-benzoic acid)porphyrin chloride, a catalytic small-molecule SOD mimetic. These data provide a distinct molecular target for the activity of ATN-224 and provide validation for SOD1 as a target for the inhibition of angiogenesis and tumor growth.

Caspase 6 has a protective role in SOD1(G93A) transgenic mice.

PubMed

Hogg, Marion C; Mitchem, Mollie R; König, Hans-Georg; Prehn, Jochen H M

2016-06-01

In amyotrophic lateral sclerosis (ALS), it has been suggested that the process of neurodegeneration starts at the neuromuscular junction and is propagated back along axons towards motor neurons. Caspase-dependent pathways are well established as a cause of motor neuron death, and recent work in other disease models indicated a role for caspase 6 in axonal degeneration. Therefore we hypothesised that caspase 6 may be involved in motor neuron death in ALS. To investigate the role of caspase 6 in ALS we profiled protein levels of caspase-6 throughout disease progression in the ALS mouse model SOD1(G93A); this did not reveal differences in caspase 6 levels during disease. To investigate the role of caspase 6 further we generated a colony with SOD1(G93A) transgenic mice lacking caspase 6. Analysis of the transgenic SOD1(G93A); Casp6(-/-) revealed an exacerbated phenotype with motor dysfunction occurring earlier and a significantly shortened lifespan when compared to transgenic SOD1(G93A); Casp6(+/+) mice. Immunofluorescence analysis of the neuromuscular junction revealed no obvious difference between caspase 6(+/+) and caspase 6(-/-) in non-transgenic mice, while the SOD1(G93A) transgenic mice showed severe degeneration compared to non-transgenic mice in both genotypes. Our data indicate that caspase-6 does not exacerbate ALS pathogenesis, but may have a protective role. Copyright © 2016 Elsevier B.V. All rights reserved.

Bid Promotes K63-Linked Polyubiquitination of Tumor Necrosis Factor Receptor Associated Factor 6 (TRAF6) and Sensitizes to Mutant SOD1-Induced Proinflammatory Signaling in Microglia.

PubMed

Kinsella, Sinéad; König, Hans-Georg; Prehn, Jochen H M

2016-01-01

Mutations in the superoxide dismutase 1 (SOD1) gene contribute to motoneuron degeneration and are evident in 20% of familial amyotrophic lateral sclerosis cases. Mutant SOD1 induces microglial activation through a stimulation of Toll-like receptors 2 and 4 (TLR2 and TLR4). In the present study, we identified the proapoptotic Bcl-2 family protein Bid as a positive regulator of mutant SOD1-induced TLR-nuclear factor-κB (NF-κB) signaling in microglia. bid-deficient primary mouse microglia showed reduced NF-κB signaling in response to TLR4 activation or exposure to conditioned medium derived from SOD1 (G93A) expressing NSC-34 cells. Attenuation of NF-κB signaling in bid-deficient microglia was associated with lower levels of phosphorylated IKKα/β and p65, with a delayed degradation of IκBα and enhanced degradation of Peli1. Upstream of IKK, we found that Bid interacted with, and promoted, the K63-linked polyubiquitination of the E3 ubiquitin ligase tumor necrosis factor receptor associated factor 6 (TRAF6) in microglia. Our study suggests a key role for Bid in the regulation of TLR4-NF-κB proinflammatory signaling during mutant SOD1-induced disease pathology. Bid promotes TLR4-NF-κB signaling by interacting with TRAF6 and promoting TRAF6 K63-linked polyubiquitination in microglia.

Bid Promotes K63-Linked Polyubiquitination of Tumor Necrosis Factor Receptor Associated Factor 6 (TRAF6) and Sensitizes to Mutant SOD1-Induced Proinflammatory Signaling in Microglia123

PubMed Central

Kinsella, Sinéad

2016-01-01

Mutations in the superoxide dismutase 1 (SOD1) gene contribute to motoneuron degeneration and are evident in 20% of familial amyotrophic lateral sclerosis cases. Mutant SOD1 induces microglial activation through a stimulation of Toll-like receptors 2 and 4 (TLR2 and TLR4). In the present study, we identified the proapoptotic Bcl-2 family protein Bid as a positive regulator of mutant SOD1-induced TLR-nuclear factor-κB (NF-κB) signaling in microglia. bid-deficient primary mouse microglia showed reduced NF-κB signaling in response to TLR4 activation or exposure to conditioned medium derived from SOD1 G93A expressing NSC-34 cells. Attenuation of NF-κB signaling in bid-deficient microglia was associated with lower levels of phosphorylated IKKα/β and p65, with a delayed degradation of IκBα and enhanced degradation of Peli1. Upstream of IKK, we found that Bid interacted with, and promoted, the K63-linked polyubiquitination of the E3 ubiquitin ligase tumor necrosis factor receptor associated factor 6 (TRAF6) in microglia. Our study suggests a key role for Bid in the regulation of TLR4-NF-κB proinflammatory signaling during mutant SOD1-induced disease pathology. Bid promotes TLR4-NF-κB signaling by interacting with TRAF6 and promoting TRAF6 K63-linked polyubiquitination in microglia. PMID:27257617

Role of nitric oxide and antioxidant enzymes in the pathogenesis of oral cancer.

PubMed

Patel, Jayendrakumar B; Shah, Franky D; Shukla, Shilin N; Shah, Pankaj M; Patel, Prabhudas S

2009-01-01

Oral cancer is the leading malignancy in India. Nitric oxide and antioxidant enzymes play an important role in etiology of oral cancer. Therefore, the present study evaluates nitric oxide and antioxidant enzyme levels in healthy individual without tobacco habits (NHT, N=30) and healthy individuals with tobacco habits (WHT, n=90), patients with oral precancers (OPC, n=15) and oral cancer patients (n=126). Blood samples were collected from the subjects. NO2 + NO3 (nitrite+nitrate), superoxide dismutase (SOD) and catalase levels were estimated using highly specific spectrophotometeric methods. Statistical analysis was done by SPSS statistical software version 10. Mean plasma NO2 + NO3 levels were elevated in patients with OPC and oral cancer patients as compared to the controls. Mean activities of erythrocyte SOD and catalase were higher in WHT than NHT. Erythrocyte SOD and catalase levels were higher in WHT and patients with OPC as compared to NHT. The erythrocyte SOD and catalase activities were lower in oral cancer patients than patients with OPC. The erythrocyte SOD activity was higher in advanced oral cancer than the early disease. Erythrocyte catalase activity was lower in poorly differentiated tumors than well and moderately differentiated tumors. Pearson's correlation analysis revealed that alterations in plasma NO2 + NO3 levels were negatively associated with changes in erythrocyte SOD activities. The data revealed that the alterations in antioxidant activities were associated with production of nitric oxide in oral cancer, which may have significant role in oral carcinogenesis.

Activities of red blood cell anti-oxidative enzymes (SOD, GPx) and total anti-oxidative capacity of serum (TAS) in men with coronary atherosclerosis and in healthy pilots.

PubMed

Zawadzka-Bartczak, Ewelina

2005-09-01

Reactive oxygen species (ROS) have been proposed to play important pathogenic roles, especially in harmful oxidative modifications of low-density cholesterol. Redox balance within the organism is largely determined by the activities of anti-oxidative enzymes of red blood cells and by the total anti-oxidative capacity of the serum (TAS). SOD and GPx activities and TAS in 13 men aged 42-65 years with coronary atherosclerosis (group I) were compared with those of both 15 clinically healthy pilots matched for age and lipid abnormalities (cholesterol and triglycerides) (group II) and 14 age-matched pilots without lipid abnormalities (group III). There were statistically significant differences in SOD and GPx activities and in TAS between the groups. 1. SOD and GPx activities and TAS were lower in men with advanced coronary atherosclerosis that in age-matched clinically healthy men with similar dyslipidemia and were even further decreased compared with clinically healthy men without dyslipidemia. 2. The decrease in SOD and GPx activities and TAS in men with advanced coronary atherosclerosis was more pronounced than the degree of hypercholesterolemia or hypertriglyceridemia. 3. If hyperlipidemia and the activity of antioxidative enzymes and TAS were considered without reference to other risk factors of atherosclerosis, it appeared that the decreases in SOD, GPx, and TAS may play a more important role in the development of the atherosclerotic process than isolated increases in free cholesterol or triglyceride levels.

Genetic Overlap in Kallmann Syndrome, Combined Pituitary Hormone Deficiency, and Septo-Optic Dysplasia

PubMed Central

Raivio, Taneli; Avbelj, Magdalena; McCabe, Mark J.; Romero, Christopher J.; Dwyer, Andrew A.; Tommiska, Johanna; Sykiotis, Gerasimos P.; Gregory, Louise C.; Diaczok, Daniel; Tziaferi, Vaitsa; Elting, Mariet W.; Padidela, Raja; Plummer, Lacey; Martin, Cecilia; Feng, Bihua; Zhang, Chengkang; Zhou, Qun-Yong; Chen, Huaibin; Mohammadi, Moosa; Quinton, Richard; Sidis, Yisrael; Radovick, Sally; Dattani, Mehul T.

2012-01-01

Context: Kallmann syndrome (KS), combined pituitary hormone deficiency (CPHD), and septo-optic dysplasia (SOD) all result from development defects of the anterior midline in the human forebrain. Objective: The objective of the study was to investigate whether KS, CPHD, and SOD have shared genetic origins. Design and Participants: A total of 103 patients with either CPHD (n = 35) or SOD (n = 68) were investigated for mutations in genes implicated in the etiology of KS (FGFR1, FGF8, PROKR2, PROK2, and KAL1). Consequences of identified FGFR1, FGF8, and PROKR2 mutations were investigated in vitro. Results: Three patients with SOD had heterozygous mutations in FGFR1; these were either shown to alter receptor signaling (p.S450F, p.P483S) or predicted to affect splicing (c.336C>T, p.T112T). One patient had a synonymous change in FGF8 (c.216G>A, p.T72T) that was shown to affect splicing and ligand signaling activity. Four patients with CPHD/SOD were found to harbor heterozygous rare loss-of-function variants in PROKR2 (p.R85G, p.R85H, p.R268C). Conclusions: Mutations in FGFR1/FGF8/PROKR2 contributed to 7.8% of our patients with CPHD/SOD. These data suggest a significant genetic overlap between conditions affecting the development of anterior midline in the human forebrain. PMID:22319038

An elevated level of copper zinc superoxide dismutase fails to prevent oxygen induced retinopathy in mice.

PubMed

Klaeger, C; de Sa, L; Klaeger, A J; Carlson, E J; Good, W V; Epstein, C J

1996-05-01

To determine whether a higher level of copper zinc superoxide dismutase (CuZnSOD) can reduce the severity of oxygen induced retinopathy (OIR) in a mouse model. CuZnSOD transgenic mice with a threefold increase in CuZnSOD activity and control non-transgenic mice were exposed to 90% oxygen for 12 hours a day during the first 5 days of life. After oxygen treatment, all mice were reared in room air for 10 days. Another group of transgenic and non-transgenic mice were kept in room air for 15 days and served as control groups for the oxygen effect. At day 15, all mice were killed and perfused with India ink. The retinas were flat mounted on slides and examined with a light microscope. There was a statistically significant increase in the incidence of OIR in mice exposed to high levels of oxygen, whether or not they were transgenic. However, there was no statistically significant difference in the severity of OIR between oxygen treated transgenic and non-transgenic mice. A threefold higher CuZnSOD activity does not protect against OIR in mice. This is an unexpected finding, since oxygen radicals are considered a major factor causing OIR, and increased CuZnSOD activity has reduced oxygen radical induced damage in several neuronal and non-neuronal systems. The possibility of a damaging role for other radicals not affected by CuZnSOD cannot be excluded.

Engineering of a novel tri-functional enzyme with MnSOD, catalase and cell-permeable activities.

PubMed

Luangwattananun, Piriya; Yainoy, Sakda; Eiamphungporn, Warawan; Songtawee, Napat; Bülow, Leif; Ayudhya, Chartchalerm Isarankura Na; Prachayasittikul, Virapong

2016-04-01

Cooperative function of superoxide dismutase (SOD) and catalase (CAT), in protection against oxidative stress, is known to be more effective than the action of either single enzyme. Chemical conjugation of the two enzymes resulted in molecules with higher antioxidant activity and therapeutic efficacy. However, chemical methods holds several drawbacks; e.g., loss of enzymatic activity, low homogeneity, time-consuming, and the need of chemical residues removal. Yet, the conjugated enzymes have never been proven to internalize into target cells. In this study, by employing genetic and protein engineering technologies, we reported designing and production of a bi-functional protein with SOD and CAT activities for the first time. To enable cellular internalization, cell penetrating peptide from HIV-1 Tat (TAT) was incorporated. Co-expression of CAT-MnSOD and MnSOD-TAT fusion genes allowed simultaneous self-assembly of the protein sequences into a large protein complex, which is expected to contained one tetrameric structure of CAT, four tetrameric structures of MnSOD and twelve units of TAT. The protein showed cellular internalization and superior protection against paraquat-induced cell death as compared to either complex bi-functional protein without TAT or to native enzymes fused with TAT. This study not only provided an alternative strategy to produce multifunctional protein complex, but also gained an insight into the development of therapeutic agent against oxidative stress-related conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

The impact of the lacto-ovo vegetarian diet on the erythrocyte superoxide dismutase activity: a study in the Romanian population.

PubMed

Boancă, M M; Colosi, H A; Crăciun, E C

2014-02-01

Recent studies have shown that vitamin B12 scavenges superoxide anion as effectively as superoxide dismutase (SOD), and has a key role in the defense against oxidative stress. The status of vitamin B12 is suboptimal in a substantial number of vegans and even vegetarians. We therefore evaluated in lacto-ovo vegetarians (LOVs) who did not take vitamin B12 supplements the impact of the duration of this diet on the vitamin B12 status, the erythrocyte SOD activity and the serum malondialdehyde (MDA) concentration. The study group included 38 non-vegetarians and 48 LOVs divided, according to the duration of this diet, into two subgroups: LOV1 (2-10 years) and LOV2 (11-29 years). The erythrocyte SOD activity and the serum concentrations of vitamin B12 and MDA were assayed. In LOVs, the mean serum vitamin B12 concentration, the erythrocyte SOD activity and the mean serum MDA concentration were statistically significantly lower that in non-vegetarians. No significant association between the serum vitamin B12 and MDA concentrations and the duration of the LOV diet were observed. A significant inverse linear correlation between SOD activity and the duration of adherence to LOV diet was observed in LOVs. The duration of LOV diet has impact only on SOD activity. Further researches, both in vitro and in vivo, are necessary to understand the underlying molecular mechanism.

Evaluation of Mn-superoxide dismutase and catalase gene expression in childhood obesity: its association with insulin resistance.

PubMed

Mohseni, Roohollah; Arab Sadeghabadi, Zahra; Goodarzi, Mohammad Taghi; Teimouri, Maryam; Nourbakhsh, Mitra; Razzaghy Azar, Maryam

2018-06-28

Obesity is associated with oxidative stress. Superoxide dismutase (SOD) is the first line of defense against reactive oxygen species (ROS), eliminating the strong superoxide radical and producing H2O2, which can then be degraded by catalase (CAT). The main objective of this study was to evaluate the gene expression antioxidant enzymes (Mn-SOD and CAT) in peripheral blood mononuclear cells (PBMCs) of obese and normal-weight children, and its association with anthropometric and biochemical parameters. Thirty obese and 30 control subjects between the ages of 8 and 16 years were enrolled in this study. Serum insulin levels were measured using enzyme-linked immunosorbent assay (ELISA), and insulin resistance was calculated using the homeostasis model assessment of insulin resistance (HOMA-IR). Biochemical parameters were also measured. PBMCs of the subjects were separated and Mn-SOD and CAT gene expression was measured using real-time polymerase chain reaction (PCR). Mn-SOD and CAT gene expression was significantly lower in the obese group compared with the control group (p<0.01). Also, a positive correlation was observed between the gene expression of Mn-SOD and CAT and body mass index (BMI), fasting blood sugar, insulin resistance, low density lipoprotein-cholesterol (LDL-C) cholesterol, triglycerides (TG) and systolic blood pressure (SBP). Induction of antioxidants, especially Mn-SOD and CAT, can lead to reduction of oxidative stress and prevent the complications of obesity in children.

Superoxide Dismutase as an Anaerobic Polypeptide 1

PubMed Central

Monk, Lorna S.; Fagerstedt, Kurt V.; Crawford, Robert M. M.

1987-01-01

The perennating organ, the rhizome, was chosen for examination of response to anoxia in the species Iris pseudacorus L., Iris germanica L. var Quechei, and Glyceria maxima (Hartm.) Holmberg. These monocots are known to differ in their tolerance of anoxia. Intact rhizomes were subjected to periods of prolonged anoxia of up to 28 days and superoxide dismutase (SOD) activity was determined in a 48 hour postanoxic recovery phase. Tests were performed to ensure the accuracy of the measured enzyme activities. In the most anoxia tolerant species, I. pseudacorus, SOD activity rose continuously during the period of imposed anoxia, and levels were maintained in the postanoxic recovery phases: 28 days brought about a 13-fold increase to 1576 U SOD per milligram protein. Small increases were found in the less anoxia tolerant I. germanica during anoxic/postanoxic phases, while a drop in activity was recorded in the least anoxia tolerant G. maxima. However, initial levels in G. maxima were more than twice as high as in the other two species. Experiments applying cycloheximide to anoxic rhizome slices of I. pseudacorus inhibited the increase in SOD activity. This indicates that SOD is, paradoxically, induced under anoxia and we suggest that in this species SOD is one of the enzymes identified as anaerobic polypeptides. The significance of the induction of an `oxygen-protecting' enzyme during complete oxygen deprivation is discussed with regard to a possible critical role during recovery from anoxic stress. PMID:16665795

Simple Biological Systems for Assessing the Activity of Superoxide Dismutase Mimics

PubMed Central

Tovmasyan, Artak; Reboucas, Julio S.

2014-01-01

Abstract Significance: Half a century of research provided unambiguous proof that superoxide and species derived from it—reactive oxygen species (ROS)—play a central role in many diseases and degenerative processes. This stimulated the search for pharmaceutical agents that are capable of preventing oxidative damage, and methods of assessing their therapeutic potential. Recent Advances: The limitations of superoxide dismutase (SOD) as a therapeutic tool directed attention to small molecules, SOD mimics, that are capable of catalytically scavenging superoxide. Several groups of compounds, based on either metal complexes, including metalloporphyrins, metallocorroles, Mn(II) cyclic polyamines, and Mn(III) salen derivatives, or non-metal based compounds, such as fullerenes, nitrones, and nitroxides, have been developed and studied in vitro and in vivo. Very few entered clinical trials. Critical Issues and Future Directions: Development of SOD mimics requires in-depth understanding of their mechanisms of biological action. Elucidation of both molecular features, essential for efficient ROS-scavenging in vivo, and factors limiting the potential side effects requires biologically relevant and, at the same time, relatively simple testing systems. This review discuses the advantages and limitations of genetically engineered SOD-deficient unicellular organisms, Escherichia coli and Saccharomyces cerevisiae as tools for investigating the efficacy and mechanisms of biological actions of SOD mimics. These simple systems allow the scrutiny of the minimal requirements for a functional SOD mimic: the association of a high catalytic activity for superoxide dismutation, low toxicity, and an efficient cellular uptake/biodistribution. Antioxid. Redox Signal. 20, 2416–2436. PMID:23964890

ALS-linked mutant SOD1 proteins promote Aβ aggregates in ALS through direct interaction with Aβ.

PubMed

Jang, Ja-Young; Cho, Hyungmin; Park, Hye-Yoon; Rhim, Hyangshuk; Kang, Seongman

2017-11-04

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motor neurons. Aggregation of ALS-linked mutant Cu/Zn superoxide dismutase (SOD1) is a hallmark of a subset of familial ALS (fALS). Recently, intracellular amyloid-β (Aβ) is detected in motor neurons of both sporadic and familial ALS. We have previously shown that intracellular Aβ specifically interacts with G93A, an ALS-linked SOD1 mutant. However, little is known about the pathological and biological effect of this interaction in neurons. In this study, we have demonstrated that the Aβ-binding region is exposed on the SOD1 surface through the conformational changes due to misfolding of SOD1. Interestingly, we found that the intracellular aggregation of Aβ is enhanced through the direct interaction of Aβ with the Aβ-binding region exposed to misfolded SOD1. Ultimately, increased Aβ aggregation by this interaction promotes neuronal cell death. Consistent with this result, Aβ aggregates was three-fold higher in the brains of G93A transgenic mice than those of non Tg. Our study provides the first direct evidence that Aβ, an AD-linked factor, is associated to the pathogenesis of ALS and provides molecular clues to understand common aggregation mechanisms in the pathogenesis of neurodegenerative diseases. Furthermore, it will provide new insights into the development of therapeutic approaches for ALS. Copyright © 2017 Elsevier Inc. All rights reserved.

WhatsApp is an effective tool for obtaining second opinion in oral pathology practice.

PubMed

Sarode, Sachin C; Sarode, Gargi S; Anand, Rahul; Patil, Shankargouda; Unadkat, Hemant

2017-08-01

The aim of this study was to find out the efficacy of WhatsApp application for obtaining second opinion on histopathological diagnosis in oral pathology practice. A total of 247 cases comprising of 34 different oral pathologies were photomicrographed using smartphone cameras through compound microscopes and sent for second opinion diagnosis (SOD) to 20 different oral pathologists using WhatsApp. Of 4795 (97.06%) total second opinion received, correct SOD were received for 4710 (98.22%) cases. Hundred percent times correct SOD was received for lesions including adenomatoid odontogenic tumor, keratinizing cystic odontogenic tumor, odontome, and dentigerous cyst. Lesions such as myoepithelial carcinoma, osteosarcoma, fibrosarcoma, and intravascular papillary endothelial hyperplasia received less percentage of correct SOD (85.71-75.75%). Correct SOD was obtained for variants of ameloblastoma (99.01%), grading of epithelial dysplasia (87.54%), and squamous cell carcinoma (95.26%). A positive correlation was observed between correct SOD and age (P = 0.0143) and experience (P = 0.0189) of the pathologist. The time taken for giving second opinion by the pathologists ranged from 81.98 ± 32.89 to 90.72 ± 38.88 min. Smartphone camera is a handy and efficient tool in capturing photomicrographs from the compound microscope. Transfer of such photomicrograph via WhatsApp is an effective and convenient approach in procuring second opinion on histopathological diagnosis of oral pathologies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Advanced age-related denervation and fiber-type grouping in skeletal muscle of SOD1 knockout mice.

PubMed

Kostrominova, Tatiana Y

2010-11-30

In this study skeletal muscles from 1.5- and 10-month-old Cu/Zn superoxide dismutase (SOD1) homozygous knockout (JLSod1(-/-)) mice obtained from The Jackson Laboratory (C57Bl6/129SvEv background) were compared with muscles from age- and sex-matched heterozygous (JLSod1(+/-)) littermates. The results of this study were compared with previously published data on two different strains of Sod1(-/-) mice: one from Dr. Epstein's laboratory (ELSod1(-/-); C57Bl6 background) and the other from Cephalon, Inc. (CSod1(-/-); 129/CD-1 background). Grouping of succinate dehydrogenase-positive fibers characterized muscles of Sod1(-/-) mice from all three strains. The 10-month-old Sod1(-/-)C and JL mice displayed pronounced denervation of the gastrocnemius muscle, whereas the ELSod1(-/-) mice displayed a small degree of denervation at this age, but developed accelerated age-related denervation later on. Denervation markers were up-regulated in skeletal muscle of 10-month-old JLSod1(-/-) mice. This study is the first to show that metallothionein mRNA and protein expression was up-regulated in the skeletal muscle of 10-month-old JLSod1(-/-) mice and was mostly localized to the small atrophic muscle fibers. In conclusion, all three strains of Sod1(-/-) mice develop accelerated age-related muscle denervation, but the genetic background has significant influence on the progress of denervation. Copyright © 2010 Elsevier Inc. All rights reserved.

Speech acquisition predicts regions of enhanced cortical response to auditory stimulation in autism spectrum individuals.

PubMed

Samson, F; Zeffiro, T A; Doyon, J; Benali, H; Mottron, L

2015-09-01

A continuum of phenotypes makes up the autism spectrum (AS). In particular, individuals show large differences in language acquisition, ranging from precocious speech to severe speech onset delay. However, the neurological origin of this heterogeneity remains unknown. Here, we sought to determine whether AS individuals differing in speech acquisition show different cortical responses to auditory stimulation and morphometric brain differences. Whole-brain activity following exposure to non-social sounds was investigated. Individuals in the AS were classified according to the presence or absence of Speech Onset Delay (AS-SOD and AS-NoSOD, respectively) and were compared with IQ-matched typically developing individuals (TYP). AS-NoSOD participants displayed greater task-related activity than TYP in the inferior frontal gyrus and peri-auditory middle and superior temporal gyri, which are associated with language processing. Conversely, the AS-SOD group only showed enhanced activity in the vicinity of the auditory cortex. We detected no differences in brain structure between groups. This is the first study to demonstrate the existence of differences in functional brain activity between AS individuals divided according to their pattern of speech development. These findings support the Trigger-threshold-target model and indicate that the occurrence of speech onset delay in AS individuals depends on the location of cortical functional reallocation, which favors perception in AS-SOD and language in AS-NoSOD. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

[Effects of trimetazidine on serum oxygen free radicals in congestive heart failure].

PubMed

Ma, Qi-lin; Xie, Yong; Zhang, Sai-dan

2002-12-28

To investigate the level of serum superoxide dismutase (SOD) and maiondialdehyde (MDA) and left ventricular systolic function in congestive heart failure (CHF) and to evaluate the influence of trimetazidine on them. Serum SOD and MDA were measured in 50 patients with heart function from grade two to four and 15 normal subjects. All the persons underwent echocardiography to determine the left ventricular end-systolic volume index (LVESVI) and the left ventricular ejection fraction (EF). The patients with CHF were randomly treated with trimetazidine plus routine therapy (n = 25) or routine therapy only (n = 25) for 8 weeks with evaluations made before and after the treatment. The SOD level and EF in the patients with CHF significantly decreased and the MDA level and LVESVI in those patients significantly increased compared with the normal subjects (P < 0.05); the severer the CHF, the greater the changes. After the treatment, the SOD level and EF increased significantly and MDA and LVESVI decreased significantly (P < 0.01) in both the trimetazidine and the conventional groups. And these changes were more obvious in the trimetazidine group than in the conventional group(P < 0.01). Oxygen free radicals play an important role in the pathophysiologic changes of CHF. The level of serum SOD and MDA can indicate the degree of CHF. Trimetazidine not only increases the level of SOD and decreases the level of MDA, but also improves the left ventricular systolic function.

The Megavirus Chilensis Cu,Zn-Superoxide Dismutase: the First Viral Structure of a Typical Cellular Copper Chaperone-Independent Hyperstable Dimeric Enzyme

PubMed Central

Lartigue, Audrey; Burlat, Bénédicte; Coutard, Bruno; Chaspoul, Florence; Claverie, Jean-Michel

2014-01-01

ABSTRACT Giant viruses able to replicate in Acanthamoeba castellanii penetrate their host through phagocytosis. After capsid opening, a fusion between the internal membranes of the virion and the phagocytic vacuole triggers the transfer in the cytoplasm of the viral DNA together with the DNA repair enzymes and the transcription machinery present in the particles. In addition, the proteome analysis of purified mimivirus virions revealed the presence of many enzymes meant to resist oxidative stress and conserved in the Mimiviridae. Megavirus chilensis encodes a predicted copper, zinc superoxide dismutase (Cu,Zn-SOD), an enzyme known to detoxify reactive oxygen species released in the course of host defense reactions. While it was thought that the metal ions are required for the formation of the active-site lid and dimer stabilization, megavirus chilensis SOD forms a very stable metal-free dimer. We used electron paramagnetic resonance (EPR) analysis and activity measurements to show that the supplementation of the bacterial culture with copper and zinc during the recombinant expression of Mg277 is sufficient to restore a fully active holoenzyme. These results demonstrate that the viral enzyme's activation is independent of a chaperone both for disulfide bridge formation and for copper incorporation and suggest that its assembly may not be as regulated as that of its cellular counterparts. A SOD protein is encoded by a variety of DNA viruses but is absent from mimivirus. As in poxviruses, the enzyme might be dispensable when the virus infects Acanthamoeba cells but may allow megavirus chilensis to infect a broad range of eukaryotic hosts. IMPORTANCE Mimiviridae are giant viruses encoding more than 1,000 proteins. The virion particles are loaded with proteins used by the virus to resist the vacuole's oxidative stress. The megavirus chilensis virion contains a predicted copper, zinc superoxide dismutase (Cu,Zn-SOD). The corresponding gene is present in some megavirus chilensis relatives but is absent from mimivirus. This first crystallographic structure of a viral Cu,Zn-SOD highlights the features that it has in common with and its differences from cellular SODs. It corresponds to a very stable dimer of the apo form of the enzyme. We demonstrate that upon supplementation of the growth medium with Cu and Zn, the recombinant protein is fully active, suggesting that the virus's SOD activation is independent of a copper chaperone for SOD generally used by eukaryotic SODs. PMID:25355875

Association between activities of SOD, MDA and Na+-K+-ATPase in peripheral blood of patients with acute myocardial infarction and the complication of varying degrees of arrhythmia.

PubMed

Yin, Yu; Han, Wei; Cao, Ying

2018-04-24

To investigate the changes of ambulatory electrocardiography and peripheral blood SOD, MDA and Na+-K+-ATP enzymes in patients of acute myocardial infarction (AMI) complicated with arrhythmia. From January 2012 to March 2015, 135 cases AMI complicated with arrhythmia in our hospital were divided into 2 groups: 70 cases in the AMI uncomplicated with arrhythmia and 65 cases in the AMI complicated with arrhythmia. 62 cases volunteers accepted physical examination in our hospital in the same period were collected as the control group. 24 hour-electrocardiogram detected by ambulatory electrocardiogram (AECG), SOD and MDA in peripheral blood detected by diagnostic reagent kit and Na+-K+-ATP enzymes in peripheral blood detected by malachite green Kit Method phosphate determination method were collected. ROC curve was used to evaluate the prognostic value of SOD, MDA and Na+-K+-ATP enzymes in AMI patients. Compared with the control group, the patients had unusual ambulatory electrocardiography had increased (P <0.05), peripheral blood SOD and Na+-K+-ATP enzymes had decreased, peripheral blood MDA had increased in 2 AMI groups (P <0.05). Compared with AMI uncomplicated with arrhythmia group, the patients had unusual ambulatory electrocardiography had increased (P <0.05), peripheral blood SOD and Na+-K+-ATP enzymes had decreased, peripheral blood MDA had increased in AMI complicated with arrhythmia group (P <0.05). Among 135 cases AMI patients, 120 (88.9%) survived and 15 (11.1%) died, of whom 11 cases were AMI complicated with arrhythmia group, 4 cases were AMI uncomplicated with arrhythmia group. Compared with the AMI uncomplicated with arrhythmia group, the dead patients were more in the AMI complicated with arrhythmia group (c2 = 4.287, P = 0.038). Compared with the survival group, the SOD and Na+-K+-ATP enzymes were significantly lower (P <0.05) and MDA significantly higher (P <0.05) in the death group. The area under the ROC curve of SOD, MDA and Na+-K+-ATP enzymes were 0.958, 0.954 and 0.993 respectively, and the cut-off values were 30.66 ng/ml, 576.70 nmol/ml and 57.42 nmol/mgh, respectively. Ambulatory electrocardiography has a close relationship with the peripheral blood SOD, MDA and Na+-K+-ATP enzymes in AMI patients complicated with arrhythmia, which might predict AMI condition. Copyright © 2018 Hellenic Society of Cardiology. Published by Elsevier B.V. All rights reserved.

Coal-burning endemic fluorosis is associated with reduced activity in antioxidative enzymes and Cu/Zn-SOD gene expression.

PubMed

Wang, Qi; Cui, Kang-ping; Xu, Yuan-yuan; Gao, Yan-ling; Zhao, Jing; Li, Da-sheng; Li, Xiao-lei; Huang, Hou-jin

2014-02-01

To study the effect of fluorine on the oxidative stress in coal-burning fluorosis, we investigated the environmental characteristics of coal-burning endemic fluorosis combined with fluorine content surveillance in air, water, food, briquette, and clay binder samples from Bijie region, Guizhou Province, southwest of China. The activities of antioxidant enzymes including copper/zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and level of lipid peroxidation such as malondialdehyde (MDA) were measured in serum samples obtained from subjects residing in the Bijie region. Expression of the Cu/Zn-SOD gene was assessed by quantitative reverse transcriptase PCR (qRT-PCR). Our results showed that people suffering from endemic fluorosis (the high and low exposure groups) had much higher MDA level. Their antioxidant enzyme activities and Cu/Zn-SOD gene expression levels were lower when compared to healthy people (the control group). Fluorosis can decrease the activities of antioxidant enzymes, which was associated with exposure level of fluorine. Down-regulation of Cu/Zn-SOD expression may play an important role in the aggravation of oxidative stress in endemic fluorosis.

Vulnerability of white matter tracts and cognition to the SOD2 polymorphism: A preliminary study of antioxidant defense genes in brain aging.

PubMed

Salminen, Lauren E; Schofield, Peter R; Pierce, Kerrie D; Bruce, Steven E; Griffin, Michael G; Tate, David F; Cabeen, Ryan P; Laidlaw, David H; Conturo, Thomas E; Bolzenius, Jacob D; Paul, Robert H

2017-06-30

Oxidative stress is a key mechanism of the aging process that can cause damage to brain white matter and cognitive functions. Polymorphisms in the superoxide dismutase 2 (SOD2) and catalase (CAT) genes have been associated with abnormalities in antioxidant enzyme activity in the aging brain, suggesting a risk for enhanced oxidative damage to white matter and cognition among older individuals with these genetic variants. The present study compared differences in white matter microstructure and cognition among 96 older adults with and without genetic risk factors of SOD2 (rs4880) and CAT (rs1001179). Results revealed higher radial diffusivity in the anterior thalamic radiation among SOD2 CC genotypes compared to CT/TT genotypes. Further, the CC genotype moderated the relationship between the hippocampal cingulum and processing speed, though this did not survive multiple test correction. The CAT polymorphism was not associated with brain outcomes in this cohort. These results suggest that the CC genotype of SOD2 is an important genetic marker of suboptimal brain aging in healthy individuals. Copyright © 2017 Elsevier B.V. All rights reserved.

A thermostable manganese-containing superoxide dismutase from the thermophilic fungus Thermomyces lanuginosus.

PubMed

Li, Duo-Chuan; Gao, Jing; Li, Ya-Ling; Lu, Jing

2005-02-01

A thermostable superoxide dismutase (SOD) from a Thermomyces lanuginosus strain (P134) was purified to homogeneity by fractional ammonium sulfate precipitation, ion-exchange chromatography on DEAE-Sepharose, Phenyl-Sepharose hydrophobic interaction chromatography, and gel filtration on Sephacryl S-100. The molecular mass of a single band of the enzyme was estimated to be 22.4 kDa, using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Using gel filtration on Sephacryl S-100, the molecular mass was estimated to be 89.1 kDa, indicating that this enzyme was composed of four identical subunits of 22.4 kDa each. The SOD was found to be inhibited by NaN3, but not by KCN or H2O2, suggesting that the SOD in T. lanuginosus was of the manganese superoxide dismutase type. The SOD exhibited maximal activity at pH 7.5. The optimum temperature for the activity was 55 degrees C. It was thermostable at 50 and 60 degrees C and retained 55% activity after 60 min at 70 degrees C. The half-life of the SOD at 80 degrees C was approximately 28 min and even retained 20% activity after 20 min at 90 degrees C.

The responses of antioxidant system in bitter melon, sponge gourd, and winter squash under flooding and chilling stresses

NASA Astrophysics Data System (ADS)

Do, Tuong Ha; Nguyen, Hoang Chinh; Lin, Kuan-Hung

2018-04-01

The objective of this paper was to review the responses of antioxidant system and physiological parameters of bitter melon (BM), sponge gourd (SG), and winter squash (WS) under waterlogged and low temperature conditions. The BM and SG plants were subjected to 0-72 h flooding treatments, and BM and WS plants were exposed to chilling at 12/7 °C (day/night) for 0-72 h. Different genotypes responded differently to environmental stress according to their various antioxidant system and physiological parameters. Increased ascorbate peroxidase (APX) and superoxide dismutase (SOD) activities provided SG and WS plants with increased waterlogging and chilling stress tolerance, respectively, compared to BM plants. The APX gene from SG and the SOD gene from WS were then cloned, and the regulation of APX and SOD gene expressions under flooding and chilling stress, respectively, were also measured. Increased expression of APX and SOD genes was accompanied by the increased activity of the enzyme involved in detoxifying reactive oxygen species (ROS) in response to those stresses. Both APX and SOD activities can be used for selecting BM lines with the best tolerances to water logging and chilling stresses.

Design and reactivity of Ni-complexes using pentadentate neutral-polypyridyl ligands: Possible mimics of NiSOD.

PubMed

Snider, Victoria G; Farquhar, Erik R; Allen, Mark; Abu-Spetani, Ayah; Mukherjee, Anusree

2017-10-01

Superoxide plays a key role in cell signaling, but can be cytotoxic within cells unless well regulated by enzymes known as superoxide dismutases (SOD). Nickel superoxide dismutase (NiSOD) catalyzes the disproportion of the harmful superoxide radical into hydrogen peroxide and dioxygen. NiSOD has a unique active site structure that plays an important role in tuning the potential of the nickel center to function as an effective catalyst for superoxide dismutation with diffusion controlled rates. The synthesis of structural and functional analogues of NiSOD provides a route to better understand the role of the nickel active site in superoxide dismutation. In this work, the synthesis of a series of nickel complexes supported by nitrogen rich pentadentate ligands is reported. The complexes have been characterized through absorption spectroscopy, mass spectrometry, and elemental analysis. X-ray absorption spectroscopy was employed to establish the oxidation state and the coordination geometry around the metal center. The reactivity of these complexes toward KO 2 was evaluated to elucidate the role of the coordination sphere in controlling superoxide dismutation reactivity. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of Manganese Superoxide Dismutase from Sphingobacterium sp. T2 as a Novel Bacterial Enzyme for Lignin Oxidation.

PubMed

Rashid, Goran M M; Taylor, Charles R; Liu, Yangqingxue; Zhang, Xiaoyang; Rea, Dean; Fülöp, Vilmos; Bugg, Timothy D H

2015-10-16

The valorization of aromatic heteropolymer lignin is an important unsolved problem in the development of a biomass-based biorefinery, for which novel high-activity biocatalysts are needed. Sequencing of the genomic DNA of lignin-degrading bacterial strain Sphingobacterium sp. T2 revealed no matches to known lignin-degrading genes. Proteomic matches for two manganese superoxide dismutase proteins were found in partially purified extracellular fractions. Recombinant MnSOD1 and MnSOD2 were both found to show high activity for oxidation of Organosolv and Kraft lignin, and lignin model compounds, generating multiple oxidation products. Structure determination revealed that the products result from aryl-Cα and Cα-Cβ bond oxidative cleavage and O-demethylation. The crystal structure of MnSOD1 was determined to 1.35 Å resolution, revealing a typical MnSOD homodimer harboring a five-coordinate trigonal bipyramidal Mn(II) center ligated by three His, one Asp, and a water/hydroxide in each active site. We propose that the lignin oxidation reactivity of these enzymes is due to the production of a hydroxyl radical, a highly reactive oxidant. This is the first demonstration that MnSOD is a microbial lignin-oxidizing enzyme.

77 FR 46767 - Plantings Associated with Eligible Facilities (RP9524.5)

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-06

... for replacement of grass and sod associated with facilities eligible for repair and restoration. Limited instances when plantings are eligible include grass and sod replacement if it is an integral part...

Rebamipide attenuates nonsteroidal anti-inflammatory drugs (NSAID) induced lipid peroxidation by the manganese superoxide dismutase (MnSOD) overexpression in gastrointestinal epithelial cells.

PubMed

Nagano, Y; Matsui, H; Shimokawa, O; Hirayama, A; Tamura, M; Nakamura, Y; Kaneko, T; Rai, K; Indo, H P; Majima, H J; Hyodo, I

2012-04-01

Nonsteroidal anti-inflammatory drugs (NSAIDs) often cause gastrointestinal complications such as gastric ulcers and erosions. Recent studies on the pathogenesis have revealed that NSAIDs induce lipid peroxidation in gastric epithelial cells by generating superoxide anion in mitochondria, independently with cyclooxygenase-inhibition and the subsequent prostaglandin deficiency. Although not clearly elucidated, the impairment of mitochondrial oxidative phosphorylation, or uncoupling, by NSAIDs is associated with the generation of superoxide anion. Physiologically, superoxide is immediately transformed into hydrogen peroxide and diatomic oxygen with manganese superoxide dismutase (MnSOD). Rebamipide is an antiulcer agent that showed protective effects against NSAID-induced lipid peroxidation in gastrointestinal tracts. We hypothesized that rebamipide may attenuate lipid peroxidation by increasing the expression of MnSOD protein in mitochondria and decreasing the leakage of superoxide anion in NSAID-treated gastric and small intestinal epithelial cells. Firstly, to examine rebamipide increases the expression of MnSOD proteins in mitochondria of gastrointestinal epithelial cells, we underwent Western blotting analysis against anti-MnSOD antibody in gastric RGM1 cells and small intestinal IEC6 cells. Secondly, to examine whether the pretreatment of rebamipide decreases NSAID-induced mitochondrial impairment and lipid peroxidation, we treated these cells with NSAIDs with or without rebamipide pretreatment, and examined with specific fluorescent indicators. Finally, to examine whether pretreatment of rebamipide attenuates NSAID-induced superoxide anion leakage from mitochondria, we examined the mitochondria from indomethacin-treated RGM1 cells with electron spin resonance (ESR) spectroscopy using a specific spin-trapping reagent, CYPMPO. Rebamipide increased the expression of MnSOD protein, and attenuated NSAID-induced mitochondrial impairment and lipid peroxidation in RGM1 and IEC6 cells. The pretreatment of rebamipide significantly decreased the signal intensity of superoxide anion from the mitochondria. We conclude that rebamipide attenuates lipid peroxidation by increasing the expression of MnSOD protein and decreasing superoxide anion leakage from mitochondria in both gastric and small intestinal epithelial cells.

Elevated free nitrotyrosine levels, but not protein-bound nitrotyrosine or hydroxyl radicals, throughout amyotrophic lateral sclerosis (ALS)-like disease implicate tyrosine nitration as an aberrant in vivo property of one familial ALS-linked superoxide dismutase 1 mutant.

PubMed

Bruijn, L I; Beal, M F; Becher, M W; Schulz, J B; Wong, P C; Price, D L; Cleveland, D W

1997-07-08

Mutations in superoxide dismutase 1 (SOD1; EC 1.15.1.1) are responsible for a proportion of familial amyotrophic lateral sclerosis (ALS) through acquisition of an as-yet-unidentified toxic property or properties. Two proposed possibilities are that toxicity may arise from imperfectly folded mutant SOD1 catalyzing the nitration of tyrosines [Beckman, J. S., Carson, M., Smith, C. D. & Koppenol, W. H. (1993) Nature (London) 364, 584] through use of peroxynitrite or from peroxidation arising from elevated production of hydroxyl radicals through use of hydrogen peroxide as a substrate [Wiedau-Pazos, M., Goto, J. J., Rabizadeh, S., Gralla, E. D., Roe, J. A., Valentine, J. S. & Bredesen, D. E. (1996) Science 271, 515-518]. To test these possibilities, levels of nitrotyrosine and markers for hydroxyl radical formation were measured in two lines of transgenic mice that develop progressive motor neuron disease from expressing human familial ALS-linked SOD1 mutation G37R. Relative to normal mice or mice expressing high levels of wild-type human SOD1, 3-nitrotyrosine levels were elevated by 2- to 3-fold in spinal cords coincident with the earliest pathological abnormalities and remained elevated in spinal cord throughout progression of disease. However, no increases in protein-bound nitrotyrosine were found during any stage of SOD1-mutant-mediated disease in mice or at end stage of sporadic or SOD1-mediated familial human ALS. When salicylate trapping of hydroxyl radicals and measurement of levels of malondialdehyde were used, there was no evidence throughout disease progression in mice for enhanced production of hydroxyl radicals or lipid peroxidation, respectively. The presence of elevated nitrotyrosine levels beginning at the earliest stages of cellular pathology and continuing throughout progression of disease demonstrates that tyrosine nitration is one in vivo aberrant property of this ALS-linked SOD1 mutant.

Maternal and postnatal high-fat diets with high ?6:?3 ratios affect the reproductive performance of male offspring in the mouse.

PubMed

Bianconi, S; Stutz, G; Solís, M R; Martini, A C; Vincenti, L M; Ponzio, M F; Luque, E; Avendaño, C; Quiroga, P; Santillán, M E

2018-05-24

High-fat diets (HFDs) are an acknowledged risk factor for male subfertility, but the underlying mechanisms remain unclear. In the present study we compared the effects of two HFDs with different ω6:ω3 ratios, one enriched with soy oil (SOD; ω6:ω3=9.62) and another enriched with sunflower oil (SFOD; ω6:ω3=51.55), with those of a commercial diet (CD; ω6:ω3=19.87), supplied from pregnancy to adulthood, on morphometric parameters and reproductive performance in adult male mice (recommended ω6:ω3 for rodents=1-6). Bodyweight was significantly higher in the SFOD than CD group, and relative testicular weight was significantly lower in the SFOD than the other two groups. SFOD altered sperm performance: it reduced sperm viability (mean±s.e.m.; 76.00±1.35% vs 82.50±1.45% and 80.63±1.00% in the SFOD vs CD and SOD groups respectively; P<0.05) and increased the percentage of immature spermatozoa (71.88±7.17% vs 51.38±5.87% and 48.00±5.72% in the SFOD vs CD and SOD groups respectively; P<0.05). The epididymal ω6:ω3 ratio was higher in the SFOD versus CD and SOD groups, whereas the unsaturation index was higher in the SOD and SFOD groups than in CD group. Sperm membrane integrity was diminished in both the SOD and SFOD groups, but there was no difference in sperm reactive oxygen species production in these two groups compared with the CD group. The fertilisation rate was lower in the SFOD compared with the CD and SOD groups. In conclusion, although both HFDs affected sperm quality, the fertilising ability was more altered by the excessive dietary ω6:ω3 ratio than by the net ω6 content.

Effects of captopril on the cysteamine-induced duodenal ulcer in the rat.

PubMed

Saghaei, Firoozeh; Karimi, Iraj; Jouyban, Abolghasem; Samini, Morteza

2012-05-01

Oxidative stress is important factor underlying in a variety of diseases. Antioxidative enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) are part of the physiological defenses against oxidative stress. Malondialdehyde (MDA) is a lipid peroxidation biomarker and its elevated level in various diseases is related to free radical damage. Cysteamine is a cytotoxic agent, acting through generation of reactive oxygen species (ROS) and may decrease defense activity of antioxidative enzymes against ROS and induce duodenal ulcer. Captopril, acts as free radical scavengers and protect against injuries from oxidative damage to tissues.The aim of this study was the evaluation of the effect of captopril against cysteamine-induced duodenal ulcer by determining duodenal damage, duodenal tissue SOD and GSH-PX activities and plasma MAD level. This study was performed on 3 groups of 7 rats each: saline, cysteamine and cysteamine plus captopril treated groups. The effect of captopril against cysteamine-induced duodenal ulcer is determined by evaluating the duodenal damage, duodenal tissue SOD and GSH-PX activities and plasma MDA level. All animals were euthanized 24h after the last treatment and 2 ml blood and duodena samples were collected for calculation of ulcer index, histopathological assessment and measurement of tissue SOD, GSH-PX activities and plasma MDA level. Cysteamine produced severe duodenal damage, decreased the activity of duodenal tissue SOD and GSH-PX and increased the plasma MDA level compared with saline pretreated rats. Pretreatment with captopril decreased the cysteamine-induced duodenal damage and plasma level of MDA and increased the activities of SOD and GSH-PX in duodenal tissue compared with cysteamine pretreated animal. Our results suggest that captopril protects against cysteamine-induced duodenal ulcer and inhibits the decrease in SOD and GSH-PX activities and lipid peroxidation by increasing antioxidant defenses. Copyright © 2010 Elsevier GmbH. All rights reserved.

Caloric restriction improves endothelial dysfunction during vascular aging: Effects on nitric oxide synthase isoforms and oxidative stress in rat aorta.

PubMed

Zanetti, Michela; Gortan Cappellari, Gianluca; Burekovic, Ismet; Barazzoni, Rocco; Stebel, Marco; Guarnieri, Gianfranco

2010-11-01

Aging is characterized by activation of inducible over endothelial nitric oxide synthase (iNOS and eNOS), impaired antioxidant activity and increased oxidative stress, which reduces nitric oxide bioavailability and causes endothelial dysfunction. Caloric restriction (CR) blunts oxidative stress. We investigated whether CR impacts endothelial dysfunction in aging and the underlying mechanisms. Aortas from young (YC, 6 months of age) and old (OC, 24 months of age) rats ad-libitum fed and from old rats caloric-restricted for 3-weeks (OR, 26%) were investigated. Endothelium-dependent vasorelaxation was impaired in OC, associated with reduced eNOS and increased iNOS expression (P<0.05). Aortic nitrite was similar in OC and YC, but the contribution of calcium-independent NOS to total NOS activity was increased whereas that of calcium-dependent NOS was reduced (p≤0.0003). Plasma thiobarbituric acid-reactive substances (TBARS) were elevated in OC as well as aortic nitrotyrosine (P<0.05). Expression of manganese superoxide dismutase (MnSOD) and total SOD activity were impaired in OC (P<0.05 vs. YC), whereas copper-zinc (CuZn) SOD expression was similar in OC and YC. CR restored endothelial dysfunction in old rats, reduced iNOS expression, total nitrite and calcium-independent NOS activity in aorta (P<0.05) without changes in eNOS expression and calcium-dependent NOS activity. Sirtuin-1 expression did not differ among groups. Plasma TBARS and aortic nitrotyrosine were reduced (P<0.05) in OR compared with OC. In OR CuZnSOD protein and SOD activity increased (P<0.05) without changes in MnSOD expression. Short-term CR improves age-related endothelial dysfunction. Reversal of altered iNOS/eNOS ratio, reduced oxidative stress and increased SOD enzyme activity rather than enhanced NO production appear to be involved in this effect. Copyright © 2010 Elsevier Inc. All rights reserved.

Extracellular superoxide dismutase increased the therapeutic potential of human mesenchymal stromal cells in radiation pulmonary fibrosis.

PubMed

Wei, Li; Zhang, Jing; Yang, Zai-Liang; You, Hua

2017-05-01

Pulmonary fibrosis induced by irradiation is a significant problem of radiotherapy in cancer patients. Extracellular superoxide dismutase (SOD3) is found to be predominantly and highly expressed in the extracellular matrix of lung and plays a pivotal role against oxidative damage. Early administration of mesenchymal stromal cells (MSCs) has been demonstrated to reduce fibrosis of damaged lung. However, injection of MSCs at a later stage would be involved in fibrosis development. The present study aimed to determine whether injection of human umbilical cord-derived MSCs (UC-MSCs) over-expressing SOD3 at the established fibrosis stage would have beneficial effects in a mice model of radiation pulmonary fibrosis. Herein, pulmonary fibrosis in mice was induced using Cobalt-60 ( 60 Co) irradiator with 20 Gy, followed by intravenous injection of UC-MSCs, transduced or not to express SOD3 at 2 h (early delivery) and 60 day (late delivery) post-irradiation, respectively. Our results demonstrated that the early administration of UC-MSCs could attenuate the microscopic damage, reduce collagen deposition, inhibit (myo)fibroblast proliferation, reduce inflammatory cell infiltration, protect alveolar type II (AE2) cell injury, prevent oxidative stress and increase antioxidant status, and reduce pro-fibrotic cytokine level in serum. Furthermore, the early treatment with SOD3-infected UC-MSCs resulted in better improvement. However, we failed to observe the therapeutic effects of UC-MSCs, transduced to express SOD3, during established fibrosis. Altogether, our results demonstrated that the early treatment with UC-MSCs alone significantly reduced radiation pulmonary fibrosis in mice through paracrine effects, with further improvement by administration of SOD3-infected UC-MSCs, suggesting that SOD3-infected UC-MSCs may be a potential cell-based gene therapy to treat clinical radiation pulmonary fibrosis. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lau, A; Ahmad, S; Chen, Y

Purpose: To quantify the simulated mean absorbed dose per technique (cGy/mAs) from a commercially available microCT scanner using various filtration techniques. Methods: Monte Carlo simulations using the Geant4 toolkit (version 10) was used utilizing the standard electromagnetic physics model. The Quantum FX microCT scanner (PerkinElmer, Waltham, MA) was modeled incorporating measured energy spectra and spatial dimensions of nominal source-to-object (SOD) distances. The energy distribution was measured using a spectrometer (X-123CdTe, Amptek Inc., Bedford, USA) for the 90 kVp X-ray beams with various filters (including no filter, 1 mm, 2 mm, 3 mm, 4 mm Al and 0.2 mm Cu +more » 2.5 mm Al). The SOD was set to 154 mm, 104 mm, and 52 mm. A total of 10 million incident particles were processed per simulation. Cutout value was set to 0.1 mm for both photon and electron. The mean dose absorbed (cGy/per incident particle) in a PMMA phantom (length of 2 cm and radius of 3 cm) were recorded. Exposure measurements were taken using a Radcal 9095 system with a protocol of 90 kVp, 200 µA, and ∼12 s beam-On time for the various filters. Results: The mean absorbed dose per mAs for various filtrations and different SOD setups indicated that the dose decreased as the SOD increased and as the amount of filtration increased. For a given SOD, the dose was reduced by as much as ∼13.7% by varying the filter (from 0.2 mm Cu + 2.5 mm Al to no filter). The maximum dose was found to be 0.39 cGy/mAs (SOD of 5.196 cm, no filter) while the minimum dose value was 0.077 cGy/mAs (SOD of 15.4 cm, .2mm Cu + 2mm Al filter). Conclusion: This study estimates easily the mean dose for objects scanned with a microCT scanner with different filtration.« less

Mitochondrial superoxide dismutase activation with 17 β-estradiol-treated human lens epithelial cells

PubMed Central

Gottipati, Srinivas

2008-01-01

Purpose 17 β-estradiol (17β-E2) protects human lens epithelial cells against oxidative stress by preserving mitochondrial function in part via the non-genomic rapid activation of prosurvival signal transduction pathways. The study described herein examined whether 17β-E2 also elicits genomic protection by influencing the expression (and activity) of mitochondrial-associated manganese superoxide dismutase (MnSOD) as a possible parallel mechanism by which 17β-E2 protects against oxidative stress. Methods Virally-transformed human lens epithelial cells (HLE-B3) were pre-incubated with 17β-E2, and mRNA or protein lysates were collected over a time course ranging from 90 min to 24 h. Positive expression of lens epithelial cell MnSOD mRNA was determined by semi-quantitative reverse transcriptase polymerase chain reaction (RT–PCR), and its levels were monitored by real-time PCR up to 24 h after 17β-E2 administration. Western blot analysis was used to examine the pattern of protein expression as influenced by 17β-E2 treatment. MnSOD activity as influenced by 17β-E2 was determined by measuring enzymatic activity. Results A significant rapid increase in the activity of MnSOD was observed with HLE-B3 cells by 90 min post-bolus addition of 17β-E2, which returned to control level by 240 min. Neither an increase in MnSOD mRNA nor in protein expression was detected up through 24 h. Conclusions These data demonstrate that 17β-E2 rapidly and transiently increases the activity of MnSOD but influences neither its mRNA expression nor its protein expression. The results suggest that (estrogen-activated) MnSOD plays an important role against mitochondrial oxidative stress by diminishing reactive oxygen species, thus promoting cell survival. PMID:18490963

Factors influencing zinc status of apparently healthy indians.

PubMed

Agte, Vaishali V; Chiplonkar, Shashi A; Tarwadi, Kirtan V

2005-10-01

To identify dietary, environmental and socio-economic factors associated with mild zinc deficiency, three zinc status indices; erythrocyte membrane zinc (RBCMZn), plasma zinc and super oxide dismutase (SOD) were assessed in free living and apparently healthy Indian population. Dietary patterns of 232 men and 223 women (20-65 yr) from rural, industrial and urban regions of Western India were evaluated by food frequency questionnaire. RBCMZn was estimated using atomic absorption spectrometry, hemoglobin and serum ceruloplasmin by spectrophotometer. On a sub sample (48 men and 51 women) plasma zinc and SOD were also assessed. Mean RBCMZn was 0.5 +/- 0.1 micromols/g protein with 46% individuals showing zinc deficiency. Mean plasma zinc was 0.98 +/- 0.12 microg/mL with 25% men and 2.5% women having values below normal range. Mean SOD was 0.97 +/- 0.1 (u/mL cells). A significant positive correlation was observed between intakes of green leafy vegetables, other vegetables and milk products with RBCMZn status (p < 0.05). But these were not correlated with plasma zinc (p > 0.2). Cereal and legume intakes were negatively correlated with RBCMZn (p < 0.05) but positively correlated with plasma zinc (p < 0.05) and not correlated with SOD (p > 0.2). Fruit and other vegetable intake were positively correlated with SOD (p < 0.05) alone. Logistic regression analyses revealed that RBCMZn was positively associated with intakes of beta-carotene, zinc and environmental conditions and negatively associated with family size (p < 0.05). Plasma zinc indicated positive association with zinc, thiamin and riboflavin intakes (p < 0.05) and SOD showed negative association with iron and family size. RBCMZn was a more sensitive indicator of long-term zinc status than plasma zinc and SOD. Prominent determinants of zinc status were intakes of beta-carotene and zinc along with environmental conditions and family size.

Structural and Molecular Basis of the Peroxynitrite-mediated Nitration and Inactivation of Trypanosoma cruzi Iron-Superoxide Dismutases (Fe-SODs) A and B

PubMed Central

Martinez, Alejandra; Peluffo, Gonzalo; Petruk, Ariel A.; Hugo, Martín; Piñeyro, Dolores; Demicheli, Verónica; Moreno, Diego M.; Lima, Analía; Batthyány, Carlos; Durán, Rosario; Robello, Carlos; Martí, Marcelo A.; Larrieux, Nicole; Buschiazzo, Alejandro; Trujillo, Madia; Radi, Rafael; Piacenza, Lucía

2014-01-01

Trypanosoma cruzi, the causative agent of Chagas disease, contains exclusively iron-dependent superoxide dismutases (Fe-SODs) located in different subcellular compartments. Peroxynitrite, a key cytotoxic and oxidizing effector biomolecule, reacted with T. cruzi mitochondrial (Fe-SODA) and cytosolic (Fe-SODB) SODs with second order rate constants of 4.6 ± 0.2 × 104 m−1 s−1 and 4.3 ± 0.4 × 104 m−1 s−1 at pH 7.4 and 37 °C, respectively. Both isoforms are dose-dependently nitrated and inactivated by peroxynitrite. Susceptibility of T. cruzi Fe-SODA toward peroxynitrite was similar to that reported previously for Escherichia coli Mn- and Fe-SODs and mammalian Mn-SOD, whereas Fe-SODB was exceptionally resistant to oxidant-mediated inactivation. We report mass spectrometry analysis indicating that peroxynitrite-mediated inactivation of T. cruzi Fe-SODs is due to the site-specific nitration of the critical and universally conserved Tyr35. Searching for structural differences, the crystal structure of Fe-SODA was solved at 2.2 Å resolution. Structural analysis comparing both Fe-SOD isoforms reveals differences in key cysteines and tryptophan residues. Thiol alkylation of Fe-SODB cysteines made the enzyme more susceptible to peroxynitrite. In particular, Cys83 mutation (C83S, absent in Fe-SODA) increased the Fe-SODB sensitivity toward peroxynitrite. Molecular dynamics, electron paramagnetic resonance, and immunospin trapping analysis revealed that Cys83 present in Fe-SODB acts as an electron donor that repairs Tyr35 radical via intramolecular electron transfer, preventing peroxynitrite-dependent nitration and consequent inactivation of Fe-SODB. Parasites exposed to exogenous or endogenous sources of peroxynitrite resulted in nitration and inactivation of Fe-SODA but not Fe-SODB, suggesting that these enzymes play distinctive biological roles during parasite infection of mammalian cells. PMID:24616096

The relationship between MnSOD Val16Ala gene polymorphism and the level of serum total antioxidant capacity with the risk of chronic kidney disease in type 2 diabetic patients: a nested case-control study in the Tehran lipid glucose study.

PubMed

Abbasi, Mehrnaz; Daneshpour, Maryam S; Hedayati, Mehdi; Mottaghi, Azadeh; Pourvali, Katayoun; Azizi, Fereidoun

2018-01-01

Several studies have shown significant associations between manganese superoxide dismutase (MnSOD) Val16Ala polymorphism and diabetic complications, but this association has not been explored in relation with chronic kidney disease (CKD) in Type 2 diabetes mellitus (T2DM) patients. Total antioxidant capacity (TAC) level changes in diabetic condition and may play important role in onset or progression of the disease and its complications. The present study investigated the association of MnSOD Val16Ala polymorphism and serum TAC with the risk of CKD in T2DM patients. This nested case-control study included 280 type 2 diabetic patients with CKD and 280 age, sex and diabetes duration-matched control subjects selected from the participants of the Tehran Lipid and Glucose Study. MnSOD val16Ala (rs4880) SNP was genotyped by the Tetra-Primer ARMS-polymerase chain reaction analysis. Serum TAC was measured using ferric-reducing antioxidant power assay. Statistical analysis was performed using STATA statistical package v.12.0 or SPSS (Version 22.0). The Ala allele of the MnSOD Val16Ala polymorphism was associated with a lower risk of CKD (odds ratio (OR), 0.55; 95% confidence interval (CI), 0.36-0.84; P  = 0.006). Median serum TAC in CKD group was 920 μmol/L and was significantly lower ( p  < 0.001) compared to the control group (1045 μmol/L). Using an adjusted conditional logistic regression, we didn't observe any significant interaction between MnSOD Val16Ala SNP with quartiles of serum TAC in relation to CKD. A significant association was found between the MnSOD Val16Ala polymorphism and CKD, but this association is not affected by serum TAC level in T2DM patients.

Activation of immunity, immune response, antioxidant ability, and resistance against Vibrio alginolyticus in white shrimp Litopenaeus vannamei decrease under long-term culture at low pH.

PubMed

Chen, Yu-Yuan; Chen, Jiann-Chu; Tseng, Kuei-Chi; Lin, Yong-Chin; Huang, Chien-Lun

2015-10-01

The growth, activation of immunity, immune parameters, and transcript levels of cytMnSOD, mtMnSOD, ecCuZnSOD, glutathione peroxidase (GPx), catalase, lysozyme, and penaeidin 3a were examined in white shrimp Litopenaeus vannamei reared at pH 6.8 and 8.1 after 24 weeks. No significant difference in growth was observed between the two groups. An in vitro study indicated that phenoloxidase activity and respiratory bursts (RB, release of the superoxide anion) were significantly higher in the haemocytes of pH 8.1 shrimp (shrimp reared at pH 8.1) than in pH 6.8 shrimp (shrimp reared at pH 6.8). An in vivo study indicated that the levels of immune parameters of pH 8.1 shrimp were significantly higher than in pH 6.8 shrimp, and the transcript levels of cytMnSOD, ecCuZnSOD, glutathione peroxidase, lysozyme, and penaeidin 3a were down-regulated in pH 6.8 shrimp. In another experiment, shrimp reared at pH 6.8 and 8.1 for 24 weeks were challenged with Vibrio alginolyticus. The mortality rate of pH 6.8 shrimp was significantly higher than in pH 8.1 shrimp over 12-168 h. Phagocytic activity, phagocytic index, and clearance efficiency to V. alginolyticus were significantly lower in pH 6.8 shrimp. We concluded that shrimp under long-term culture at pH 6.8 exhibited decreased resistance against V. alginolyticus as evidenced by reductions in the activation of immunity and immune parameters together with decreased transcript levels of cytMnSOD, ecCuZnSOD, GPx, lysozyme, and penaeidin 3a. Copyright © 2015 Elsevier Ltd. All rights reserved.

Increased Zn/Glutathione Levels and Higher Superoxide Dismutase-1 Activity as Biomarkers of Oxidative Stress in Women with Long-Term Dental Amalgam Fillings: Correlation between Mercury/Aluminium Levels (in Hair) and Antioxidant Systems in Plasma

PubMed Central

Cabaña-Muñoz, María Eugenia; Parmigiani-Izquierdo, José María; Bravo-González, Luis Alberto; Kyung, Hee-Moon; Merino, José Joaquín

2015-01-01

Background The induction of oxidative stress by Hg can affect antioxidant enzymes. However, epidemiological studies have failed to establish clear association between dental fillings presence and health problems. Objectives To determine whether heavy metals (in hair), antioxidant enzymes (SOD-1) and glutathione levels could be affected by the chronic presence of heavy metals in women who had dental amalgam fillings. Materials and Methods 55 hair samples (42 females with amalgam fillings and 13 female control subjects) were obtained. All subjects (mean age 44 years) who had dental amalgam filling for more than 10 years (average 15 years). Certain metals were quantified by ICP-MS (Mass Spectrophotometry) in hair (μg/g: Al, Hg, Ba, Ag, Sb, As, Be, Bi, Cd, Pb, Pt, Tl, Th, U, Ni, Sn, Ti) and SOD-1 and Glutathione (reduced form) levels in plasma. Data were compared with controls without amalgams, and analyzed to identify any significant relation between metals and the total number of amalgam fillings, comparing those with four or less (n = 27) with those with more than four (n = 15). As no significant differences were detected, the two groups were pooled (Amlgam; n = 42). Findings Hg, Ag, Al and Ba were higher in the amalgam group but without significant differences for most of the heavy metals analyzed. Increased SOD-1 activity and glutathione levels (reduced form) were observed in the amalgam group. Aluminum (Al) correlated with glutathione levels while Hg levels correlated with SOD-1. The observed Al/glutathione and Hg/SOD-1 correlation could be adaptive responses against the chronic presence of mercury. Conclusions Hg, Ag, Al and Ba levels increased in women who had dental amalgam fillings for long periods. Al correlated with glutathione, and Hg with SOD-1. SOD-1 may be a possible biomarker for assessing chronic Hg toxicity. PMID:26076368

Oxidative Stress-Related Genetic Variants May Modify Associations of Phthalate Exposures with Asthma

PubMed Central

Wang, I-Jen; Karmaus, Wilfried J. J.

2017-01-01

Background: Phthalate exposure may increase the risk of asthma. Little is known about whether oxidative-stress related genes may alter this association. First, this motivated us to investigate whether genetic polymorphisms of the oxidative-stress related genes glutathione S-transferase Mu 1 (GSTM1), glutathione S-transferase pi 1 (GSTP1), superoxide dismutase 2 (SOD2), catalase (CAT), myeloperoxidase (MPO), and EPHX1 in children are associated with phthalate urine concentrations. Second, we addressed the question whether these genes may affect the influence of phthalates on asthma. Methods: In a case-control study composed of 126 asthmatic children and 327 controls, urine phthalate metabolites (monoethyl phthalate (MEP), monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), and mono(2-ethyl-5-hydroxyhexyl)phthalate (MEHHP) were measured by UPLC-MS/MS at age 3. Genetic variants were analyzed by TaqMan assay. Information on asthma and environmental exposures was also collected. Analyses of variance and logistic regressions were performed. Results: Urine MEHHP levels were associated with asthma (adjusted OR 1.33, 95% CI (1.11–1.60). Children with the GSTP1 (rs1695) AA and SOD2 (rs5746136) TT genotypes had higher MEHHP levels as compared to GG and CC types, respectively. Since only SOD2 TT genotype was significantly associated with asthma (adjusted OR (95% CI): 2.78 (1.54–5.02)), we estimated whether SOD2 variants modify the association of MEHHP levels and asthma. As MEHHP concentrations were dependent on GSTP1 and SOD2, but the assessment of interaction requires independent variables, we estimated MEHHP residuals and assessed their interaction, showing that the OR for SOD2 TT was further elevated to 3.32 (1.75–6.32) when the residuals of MEHHP were high. Conclusions: Urine phthalate metabolite concentrations are associated with oxidative-stress related genetic variants. Genetic variants of SOD2, considered to be reflect oxidative stress metabolisms, might modify the association of phthalate exposure with asthma. PMID:28208751

Oxidative Stress-Related Genetic Variants May Modify Associations of Phthalate Exposures with Asthma.

PubMed

Wang, I-Jen; Karmaus, Wilfried J J

2017-02-08

Background: Phthalate exposure may increase the risk of asthma. Little is known about whether oxidative-stress related genes may alter this association. First, this motivated us to investigate whether genetic polymorphisms of the oxidative-stress related genes glutathione S -transferase Mu 1 ( GSTM1 ), glutathione S -transferase pi 1 ( GSTP1 ), superoxide dismutase 2 ( SOD2 ), catalase ( CAT ), myeloperoxidase ( MPO ), and EPHX1 in children are associated with phthalate urine concentrations. Second, we addressed the question whether these genes may affect the influence of phthalates on asthma. Methods: In a case-control study composed of 126 asthmatic children and 327 controls, urine phthalate metabolites (monoethyl phthalate (MEP), monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), and mono(2-ethyl-5-hydroxyhexyl)phthalate (MEHHP) were measured by UPLC-MS/MS at age 3. Genetic variants were analyzed by TaqMan assay. Information on asthma and environmental exposures was also collected. Analyses of variance and logistic regressions were performed. Results: Urine MEHHP levels were associated with asthma (adjusted OR 1.33, 95% CI (1.11-1.60). Children with the GSTP1 (rs1695) AA and SOD2 (rs5746136) TT genotypes had higher MEHHP levels as compared to GG and CC types, respectively. Since only SOD2 TT genotype was significantly associated with asthma (adjusted OR (95% CI): 2.78 (1.54-5.02)), we estimated whether SOD2 variants modify the association of MEHHP levels and asthma. As MEHHP concentrations were dependent on GSTP1 and SOD2 , but the assessment of interaction requires independent variables, we estimated MEHHP residuals and assessed their interaction, showing that the OR for SOD2 TT was further elevated to 3.32 (1.75-6.32) when the residuals of MEHHP were high. Conclusions: Urine phthalate metabolite concentrations are associated with oxidative-stress related genetic variants. Genetic variants of SOD2 , considered to be reflect oxidative stress metabolisms, might modify the association of phthalate exposure with asthma.

Antioxidant genes of the emerald ash borer (Agrilus planipennis): gene characterization and expression profiles.

PubMed

Rajarapu, Swapna Priya; Mamidala, Praveen; Herms, Daniel A; Bonello, Pierluigi; Mittapalli, Omprakash

2011-06-01

Phytophagous insects frequently encounter reactive oxygen species (ROS) from exogenous and endogenous sources. To overcome the effect of ROS, insects have evolved a suite of antioxidant defense genes such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione peroxidase (GPX). The emerald ash borer (Agrilus planipennis Fairmaire), an exotic invasive insect pest from Asia has killed millions of ash trees and continues to invade North America at a rapid pace. From an on-going expressed sequence tag (EST) project of A. planipennis larval tissues, we identified ESTs coding for a Cu-Zn SOD (ApSOD1), a CAT (ApCAT1) and a GPX (ApGPX1). A multiple sequence alignment of the derived A. planipennis sequences revealed high homology with other insect sequences at the amino acid level. Phylogenetic analysis of ApSOD1 grouped it with Cu-Zn SODs of other insect taxa. Quantitative real time PCR (qRT-PCR) analysis in different larval tissues (midgut, fat body, Malpighian tubule and cuticle) revealed high mRNA levels of ApCAT1 in the midgut. Interestingly, high mRNA levels for both ApSOD1 and ApGPX1 were observed in the Malpighian tubules. Assay of mRNA levels in developmental stages (larva, prepupa and adults) by qRT-PCR indicated high transcript levels of ApCAT1 and ApGPX1 in larval and prepupal stages with a decline in adults. On the other hand, the transcript levels of ApSOD1 were observed to be constitutive in all the developmental stages assayed. Results obtained reflect a plausible role of these A. planipennis antioxidant genes in quenching ROS from both diet (ash allelochemicals) as well as endogenous sources. These studies further help in understanding the adaptation/invasiveness of A. planipennis. Copyright © 2011 Elsevier Ltd. All rights reserved.