Multifaceted superoxide dismutase 1 expression in amyotrophic lateral sclerosis patients:a rare occurrence?

Amyotrophic lateral sclerosis(ALS)is a neuromuscular condition resulting from the progressive degeneration of motor neurons in the cortex,brainstem,and spinal cord.While the typical clinical phenotype of ALS involves both upper and lower motor neurons,human and animal studies over the years have highlighted the potential spread to other motor and non-motor regions,expanding the phenotype of ALS.Although superoxide dismutase 1(SOD1)mutations represent a minority of ALS cases,the SOD1 gene remains a milestone in ALS research as it represents the first genetic target for personalized therapies.Despite numerous single case reports or case series exhibiting extramotor symptoms in patients with ALS mutations in SOD1(SOD1-ALS),no studies have comprehensively explored the full spectrum of extramotor neurological manifestations in this subpopulation.In this narrative review,we analyze and discuss the available literature on extrapyramidal and non-motor features during SOD1-ALS.The multifaceted expression of SOD1 could deepen our understanding of the pathogenic mechanisms,pointing towards a multidisciplinary approach for affected patients in light of new therapeutic strategies for SOD1-ALS.

Research Progress on Synthesis of Superoxide Dismutase Mimics

Research on the synthesis of superoxide dismutase mimics by chemical and biologi-cal synthetic methods were reviewed.The advantages and limitations were analyzed.A prospect for the future development of superoxide dismutase mimics is proposed.

The landscape of cognitive impairment in superoxide dismutase 1-amyotrophic lateral sclerosis

Although mutations in the superoxide dismutase 1 gene account for only a minority of total amyotrophic lateral sclerosis cases,the discovery of this gene has been crucial for amyotrophic lateral sclerosis research.Since the identification of superoxide dismutase 1 in 1993,the field of amyotrophic lateral sclerosis genetics has considerably widened,improving our understanding of the diverse pathogenic basis of amyotrophic lateral sclerosis.In this review,we focus on cognitive impairment in superoxide dismutase 1-amyotrophic lateral sclerosis patients.Literature has mostly reported that cognition remains intact in superoxide dismutase 1-amyotrophic lateral sclerosis patients,but recent reports highlight frontal lobe function frailty in patients carrying different superoxide dismutase 1-amyotrophic lateral sclerosis mutations.We thoroughly reviewed all the various mutations reported in the literature to contribute to a comprehensive database of superoxide dismutase 1-amyotrophic lateral sclerosis genotype-phenotype correlation.Such a resource could ultimately improve our mechanistic understanding of amyotrophic lateral sclerosis,enabling a more robust assessment of how the amyotrophic lateral sclerosis phenotype responds to different variants across genes,which is important for the therapeutic strategy targeting genetic mutations.Cognition in superoxide dismutase 1-amyotrophic lateral sclerosis deserves further longitudinal research since this peculiar frailty in patients with similar mutations can be conditioned by external factors,including environment and other unidentified agents including modifier genes.

Effect of alcohol exposure on hepatic superoxide generation and hepcidin expression

AIM: To understand the role of mitochondrial-produced superoxide(O 2 ?) in the regulation of iron-regulatory hormone, hepcidin by alcohol in the liver. METHODS: For alcohol experiments, manganese superoxide dismutase knockout mice heterozygous for Sod2 gene expression(Sod2 +/) and age-matched littermate control mice(LMC), expressing Sod2 gene on both alleles, were exposed to either 10%(w/v) ethanol in the drinking water or plain water(control) for 7 d. Total cellular O 2 ? levels in hepatocytes isolated from the livers of mice were measured by electron paramagnetic resonance spectroscopy. The mitochondrial-targeted, O 2 ?-sensitive fluorogenic probe, MitoSOX Red and flow cytometry were utilized to measure O 2 ? in mitochondria. Gene and protein expression were determined by Taqman Real-time quantitative PCR and Western blotting, respectively. RESULTS: Sod2 +/- mice expressed 40% less MnSOD protein(SOD2) in hepatocytes compared to LMC mice. The deletion of Sod2 allele did not alter the basal expression level of hepcidin in the liver. 10% ethanol exposure for 1 wk inhibited hepatic hepcidin mRNA expression three-fold both in Sod2 +/ and LMC mice. O 2 ? levels in hepatocytes of untreated Sod2 +/ mice were three-fold higher than in untreated LMC mice, as observed by electron paramagnetic resonance spectroscopy. O 2 ? levels in mitochondria of Sod2 +/ mice were four-fold higher than in mitochondria of untreated LMC mice, as measured by MitoSOX Red fluorescence and flow cytometry. Alcohol induced a two-fold higher increase in O 2 ? levels in hepatocytes of LMC mice than in Sod2 +/ mice compared to respective untreated counterparts. In contrast, 1 wk alcohol exposure did not alter mitochondrial O 2 ? levels in both Sod2 +/- and control mice. CONCLUSION: Mitochondrial O2 ? is not involved in the inhibition of liver hepcidin transcription and thereby regulation of iron metabolism by alcohol. These findings also suggest that short-term alcohol consumption significantly elevates O 2 ? levels in hepatocytes, which appears not to originate from mitochondria.

Superoxide Anion Radical Scavenging Ability of Quaternary Ammonium Salt of Chitosan

A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The IC50 values of these compounds range from 280 to 880 μg/mL, which should be attributed to their different substitutes.

Possible Involvement of NADPH Oxidase in Lanthanide Cation-Induced Superoxide Anion Generation in BY-2 Tobacco Cell Suspension Culture

A rapid and concentration-dependent generation of superoxide anion （·O2^-）, measured with a superoxide-specific Cypridina luciferin-derived chemiluminescent reagent, was observed when two lanthanide salts （LaCl3 and CdCl3 ） were added to tobacco （ Nicotiana tabacum） cell suspension culture. Addition of superoxide dismutase （480 U·ml^-1） and Tiron （5 μmol·L^-1） to cell culture suspension decreases the level of lanthanide cation-induced ·O2^- generation, suggesting that ·O2^- generation is extra-cellular. Pretreatment of the cell culture suspension with diphenyleneiodonium （10 and 50 μmol·L^-1 ）, quinacrine （ 1 and 5 mmol· L^-1 ） and imidazol （ 10 mmol· L^-1 ）, inhibitors of NADPH oxidase, notably inhibits the generation of superoxide induced by lanthanide cation, implying the possible involvement of activation of NADPH oxidase. In addition, addition of SHAM （1 and 5 mmol· L^-1）, azide （0.2 and 1 mmol· L^-1 ）, inhibitor of peroxidase, has no influence on ·O2^- generation.

Purification and Properties of Superoxide Dismutase(SOD) in Allium Sativum

Superoxide dismutases(SODs) were purified to homogeneity from Allium Sativum by means of ammonium sulfate precipitation and column chromatography with DEAE-cellulose(DE52) and Sephadex G-75. Based on sodium dodecyl sulfate\|polyacrylamide gel electrophoresis(SDS-AGE), Allium Sativum is predicted to contain four SODs. The molecular weights of the native SODs are 41 3 kD, 37 0 kD, 35 2 kD and 31 0 kD, which consist of subunits of 20 7 kD, 18 4 kD, 17 7 kD and 15 4 kD respectively. Because of their specific sensitivity to hydrogen peroxide, cyanogens potassium and chloroform\|alcohol, the SODs in Allium Sativum appear to be Cu, Zn-SOD isoenzymes. The isoelectric analysis indicates that three of the four isoenzymes are acidic proteins with isoelectric points at pH 3 5, 3 7 and 4 0, respectively, and the fourth one is a basic protein with isoeletric point at pH 8 5.

Differential Expression of Two Cytosolic Ascorbate Peroxidases and Two Superoxide Dismutase Genes in Response to Abiotic Stress in Rice

Superoxide dismutase (SOD) and ascorbate peroxidase (APX) play central roles in the pathway for scavenging reactive oxygen species in plants, thereby contributing to the tolerance against abiotic stress. Here we report the responses of cytosolic SOD (cSOD; sodCc1 and sodCc2) and cytosolic APX (cAPX; OsAPX1 and OsAPX2) genes to oxidative and abiotic stress in rice. RNA blot analyses revealed that methyl viologen treatment caused a more prominent induction of cAPXs compared with cSODs, and hydrogen peroxide treatment induced the expression of cAPXs whereas cSODs were not affected. These results suggest that cAPXs play more important roles in defense against oxidative stress compared with cSODs. It is noted that cSODs and cAPXs showed coordinate response to abscisic acid treatment which induced both sodCc1 and OsAPX2. However, cSODs and cAPXs responded differentially to drought, salt and chilling stress, which indicates that cSOD and cAPX genes are expressed differentially in response to oxidative and abiotic stress in rice.

The in vitro effects of superoxide, some commercially available antioxidants and red palm oil on sperm motility

In this study, two commercially available superoxide scavengers, tetrakis （1-methyl-4-pyridyl） porphyrin （Mn[III]TMPyP） and superoxide dismutase （SOD）, as well as red palm oil （RPO）, a natural vegetable oil, had been used to investigate their possible in vitro effects against the toxic effects of superoxide （O2＋） on human sperm motility. Semen samples were obtained from 12 normozoospermic healthy volunteer donors aged between 19 and 23 years. The O2＋donor 2,3-dimetoxyl-l,4-naphthoquinone （DMNQ） （2.5 μmol· L^-1-100 μmol· L^-1） was added to normozoospermic post-swim-up sperm in the presence or absence of Mn（III）TMPyP （50 μmol· L^-1）, SOD （50 IU） or RPO （0.1% or 0.5%）. Computer-assisted semen analysis was used to analyze various motility parameters. The parameters of interest were percentage of motile cells, progressive motility, rapid cells and static cells. Concentrations of higher than 25 μmol· L^-1 DMNQ were detrimental to sperm motility. Mn（III）TMPyP was able to attenuate the effect of O2＋ on the motility parameters. In vitro addition of SOD and RPO showed harmful effects on sperm motility.

Expression and Characterization of an Active Chimeric Protein of Human Extracellular Superoxide Dismutase and hCuZnSOD in Pichia pastoris

Mammalian cells express two isoforms of Cu- and Zn-containing superoxide dismutases（SODs）, CuZn-SOD and extracellular SOD（EC-SOD）, involved in the defense system against reactive oxygen species（ROS）. The two SODs have structurally homologous centre domain with distinct N- and C-terminuses, resulting in the different characteristics of the structure and function of the two molecules. We generated a hybrid SOD molecule（namely hy- SOD） via replacing the N- and C-terminuses of hCuZnSOD with the counterparts of hEC-SOD. The hySOD was expressed in host Pichia pastoris and the purified protein was a dimer with a molecular weight of about 34000. A series of activity analyses indicates that the hySOD is similar to hEC-SOD in heat-stability, and has the activity of protecting the host cell against heat shock and oxidative stress. Our results show evidence for the study on the compound activity of multiple SOD molecules, and may be important for understanding the relationship between structure and function of hEC-SOD and hCuZnSOD.

Formation of Superoxide Radical and Hydrogen Peroxide Enhanced by Trinitrotoluene in Rat Liver, Brain, Kidney, and Testicle in Vitro and Monkey Liver in Vivo

Trinitrotoluene (TNT) increased the formation of adrenochrome from adrenaline and the formation of formaldehyde from methanol in rat liver mitochondria and microsomes in vitro as well as in monkey liver mitrochondria and microsomes in vivo. The effects were more prominent at higher TNT concentrations. These findings indicate that TNT enhances the production of superoxide radicals (O_2^-) and hydrogen peroxide (H_2O_2). The production of O_2^- was more prominent in systems containing added TNT than in those containing added benzyl viologen. H_2O_2 production by mitochondria was more pronounced in the liver than in other organs, but its production by microsomes was more pronounced in the brain than in other organs. The results suggest that TNT undergoes cycling reduction which produces oxidative stress. 1989 Academic Press, Inc.

Relationship of Uric Acid with Superoxide Dismutase (Sod) in Induced Hyperuricemic Rat Model

Increase uric acid levels have been found in oxidative stress. Urate radicals do not react with oxygen to form another peroxy radical, thus increasing the efficacy of uric acid as an antioxidant. Therefore, this study is designed to measure the level of uric acids and find out the relationship of uric acid with superoxide dismutase in induced hyperuricemic model. Forty male albino rats with an average weight of 180 ± 2 g were selected. The rats were grouped. The animals were fed on standard diet and given tap water ad libitum until treatment. Albino rats were divided into four groups. Group A(10)-control given only standard diet, group B(10) fed on 60% fructose with standard diet , group C(10) fed on fructose, standard diet and intraperitonially oxonic acid 250 mg/kg and group D (10) only on injection intraperotonially oxonic acid 250 mg/kg. At the end of study 10 mL of blood was drawn from heart of rats. Then blood was estimated for superoxide dismutase and uric acids done by kit methods randox-manual/Rx monza UA230/UA 233. Results: In Group C superoxide dismutase was found to be 32 % (244 mg/dL ± 2.23) more than control. In the same group the uric acid concentration was highly significantly correlated with control. Conclusion: The uric acid concentration increases when we take fructose up to 60% in our diet. It also increases superoxide dismutase concentration. More than this value may have inverse effect on the uric acid level and its role as an antioxidant may become inversed.

Study on Inhibition Effects of Rare Earths on Superoxide Anion Radical by Using Pulse Radiolysis

The inhibition effect of rare earths on the production of ·O - 2 produced by radiolysis of aqueous sodium formate saturated with O 2 with high energy pulse electron beam was studied. The result indicates that rare earth nitrate obviously inhibits the production of ·O - 2 . The inhibition rate is between 28 6% and 92%. The inhibition effect increases with the increase of rare earth nitrates concentration. The distinguish dose effect relationship was observed.

A High Sensitivity Detection Method of Singlet Oxygen and Superoxide Anion

This paper, for the first time, reports a method that can be used as a highly sensitive probe for singlet oxygen (1O2) and superoxide anion (O2-) in vitro or in vivo. FCLA(3,7-dihydro-6-{4-[2-(N'-(5-fluoresceinyl)thioureido)ethoxy]phenyl}-2-methylimidazo{1,2-a}pyrazin-3-one sodium salt), a chemiluminescence (CL) analysis reagent, has been reported to sensitively react with 1O2 and O2- to emit photons with a spectral peak of 525nm. In this work, when human serum albumin (HSA) was added into FCLA solution to enhance the CL intensity, approximately 20 times, compared to that without HSA. The enhanced CL had the same 525 nm spectral peak, identical to that without HSA. By gradually reducing the molecular oxygen content in the solution, we find that the auto-oxidation of oxygen molecules dissolved in the solution plays an important role in the CL process. Based on these experimental evidences, we propose a novel and highly sensitive detection method of 1O2 and O2-, which may have a great potential in chemical and medical applications.

Characterization of a thermostable manganese-containing superoxide dismutase from inshore hot spring thermophile Thermus sp.JM1

A thermostable superoxide dismutase （SOD） from the inshore thermophile Thermus sp. JM1 was purified to homogeneity by steps of fractional ammonium sulfate precipitation, DEAE-Sepharose chromatography and Phenyl-Sepharose chromatography. The specific activity of the purified native enzyme was 1 656 U/mg. A sod gene from this strain was cloned and overexpressed in Escherichia coli （E. coli）. The prepared apo-enzyme of the purified recombinant SOD （rSOD） was reconstituted with either Fe or Mn by means of incubation with appropriate metal salts. As a result, only Mn 2＋ - reconstituted rSOD （Mn-rSOD） exhibited the specific activity of 1 598 U/mg. SOD from Thermus sp. JM1 was Mn-SOD, judging by the specific activities analysis of Fe or Mn reconstituted rSODs and the insensitivity of the native SOD to both cyanide and H 2 O 2 . Both the native SOD and Mn- rSOD were determined to be homotetramers with monomeric molecular mass of 26 kDa and 27.5 kDa, respectively. They had high thermostability at 50 ° C and 60 ° C, and showed striking stability across a wide pH span from 4.0 to 11.0.

L-carnitine protects C2C12 cells against mitochondrial superoxide overproduction and cell death

AIM To identify and characterize the protective effect that L-carnitine exerted against an oxidative stress in C2C12 cells.METHODS Myoblastic C2C12 cells were treated with menadione, a vitamin K analog that engenders oxidative stress, and the protective effect of L-carnitine(a nutrient involved in fatty acid metabolism and the control of the oxidative process), was assessed by monitoring various parameters related to the oxidative stress, autophagy and cell death. RESULTS Associated with its physiological function, a muscle cell metabolism is highly dependent on oxygen and may produce reactive oxygen species(ROS), especially under pathological conditions. High levels of ROS are known to induce injuries in cell structure as they interact at many levels in cell function. In C2C12 cells, a treatment with menadione induced a loss of transmembrane mitochondrial potential, an increase in mitochondrial production of ROS; it also induces autophagy and was able to provoke cell death. Pre-treatment of the cells with L-carnitine reduced ROS production, diminished autophagy and protected C2C12 cells against menadione-induced deleterious effects. CONCLUSION In conclusion, L-carnitine limits the oxidative stress in these cells and prevents cell death.

Regulation of Content of Malondialdehyde by Siqi Decoction via Increasing Activity of Superoxide Dismutase in Blood Serum of Rats with Myocardial Ischemia

Effect of Siqi decoction on myocardial ischemia is to prevent cardiac myocyte membrane from damage associated with oxygen free radicals related to NO. To research the regulatoin of the content of malondialdehyde by Siqi decoction, an index of lipid peroxidation, via increasing activity of superoxide dismutase in blood serum of rats with Myocardial Ischemia, the model of myocardium ischemia was made in Wistar rats with posterior pituitary injection through vein in tail. Siqi decoction, Diaoxinxuekang（DK） and Fufangdanshenpian（FD）, the latter two drugs of which are effective TCM drugs of anti-myocardial ischemia at present, were administrated to the rats with myocardium ischemia for 5 days to compare the effect of them on myocardium ischemia as reference drugs via measuring the changes of the content of malondialdehyde and the activity of superoxide dismutase in the rat blood serum with myocardial ischemia. There were a remarkable increase in the activity of superoxide dismutase and a decrease in the content of malondialdehyde in the serum of the rats administered Siqi decoction compared with those of the rats in control group, p〈0.05. The contents of MDA in the serum of the prevention group rats in the experiments are lower than those of the cure group rats. Anti-Myocardium Ischemia mechanism of Siqi decoction is the regulation of the content of malondialdehyde via increasing activity of superoxide dismutase in the serum of Rats with myocardial ischemia and stimulating the activity of NOS in serum so as to increase NO concentration.

Extracellular superoxide dismutase VdSOD5 is required for virulence in Verticillium dahliae

Plants produce reactive oxygen species(ROS) to defend pathogens. To counteract this attack, certain pathogens express superoxide dismutases(SODs) to scavenge host-derived ROS. However, the roles of SODs in Verticillium dahliae, an important vascular pathogen, are not clear. Our previous study has shown that a putative extracellular SOD(VdSOD5) of V. dahliae is significantly induced by culturing in cotton tissues, suggesting that VdSOD5 may play an important role in host–pathogen interactions and virulence. Here, we showed that VdSOD5 encoded a superoxide dismutase with a cofactor copper-binding site and a functional signal peptide that can conduct protein secretion in an invertase-mutated yeast strain. The mutations in VdSOD5(ΔVdSOD5) did not change the normal vegetative growth and conidial production but reduced the virulence of V. dahliae on susceptible host cotton. Further studies showed that the transcription of Vd SOD5 was significantly up-regulated during the early stage of infection, and the loss-of-function of VdSOD5 decreased culture filtrate and fungal tissue SOD activities of V. dahliae by 74 and 28%, respectively. Compared to the wild-type strain Vd991, the ΔVdSOD5 showed the same sensitivity to the intracellular ROS generator menadione. Furthermore, nitroblue tetrazolium(NBT) staining demonstrated that VdSOD5 functioned in the detoxification of superoxides generated by host roots during infection. These results suggest that VdSOD5 of V. dahliae is an important virulence factor, secreted out of cells to combat host-derived ROS.

A Novel Isoenzyme of CuZn-superoxide Dismutase from Nicotiana tobacum

An isoenzyme of CuZnsuperoxide dismutase, denoted as CuZnSODⅢ, has been separated and purified from Nicotiana Tobacum (tobacco) leaves to apparent homogeneity. Its molecular mass is 22976.6Da. It is composed of one subunit, which is consisted of 187 amine acid residues and contains 1 copper and 0.5 zinc atom. The activation energy of the thermal denaturation process has been obtained as about 143.5kJmol-1. Meanwhile, some properties of spectra were investigated.

Purification and Characterization of Superoxide Dismutase(SOD) from Camellia Pollen

A superoxide dismutase（ SOD ） was purified to homogeneity from fresh camellia pollen by means of ammonium sulfate precipitation and column chromatography with DEAE-cellulose（ DE52 ）, Sephadex G-100 and phenyl sepharose^TM 6 Fast Flow columns. Its specific activity could reach to 4034 U/mg protein and it was determined to be Cu/ Zn-SOD according to its different sensitivities to different inhibitors. The molecular weight of the SOD and its subunit were 69500 and 34700, respectively, based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS- PAGE）, which implicates that the SOD in camellia pollen is a dimmer composed of two identical subunits. The isoelectric point of the enzyme was determined to be 4. 1 by isoelectric focusing electrophoresis and the N-terminal amino acid was identified to be Gly by the DNS-Cl method. Its α-Helix was also calculated to be approximately 21.8% according to the circular dichroism（CD） spectra.