Activity of CdTe Quantum-Dot-Tagged Superoxide Dismutase and Its Analysis in Capillary Electrophoresis

Quantum dots (QDs) have a broad range of applications in cell biolabeling, cancer treatment, metastasis imaging, and therapeutic drug monitoring. Despite their wide use, relatively little is known about their influence on other molecules. Interactions between QDs and proteins can influence the properties of both nanoparticles and proteins. The effect of mercaptosuccinic acid-capped CdTe QDs on intercellular copper–zinc superoxide dismutase (SOD1)—one of the main enzymatic antioxidants—was investigated. Incubation of SOD1 with QDs caused an increase in SOD1 activity, unlike in the case of CdCl2, which inhibited SOD1. Moreover, this effect on SOD1 increased with the size and potential of QDs, although the effect became clearly visible in higher concentrations of QDs. The intensity of QD-SOD1 fluorescence, analyzed with the use of capillary electrophoresis with laser-induced fluorescence detection, was dependent on SOD1 concentration. In the case of green QDs, the fluorescence signal decreased with increasing SOD1 concentration. In contrast, the signal strength for Y-QD complexes was not dependent on SOD1 dilutions. The migration time of QDs and their complexes with SOD1 varied depending on the type of QD used. The migration time of G-QD complexes with SOD1 differed slightly. However, in the case of Y-QD complexes with SOD1, the differences in the migration time were not dependent on SOD concentration. This research shows that QDs interact with SOD1 and the influence of QDs on SOD activity is size-dependent. With this knowledge, one might be able to control the activation/inhibition of specific enzymes, such as SOD1.

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Rat lung antioxidant enzymes: differences in perinatal gene expression and regulation

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1992.263.4.l466 ◽

1992 ◽

Vol 263 (4) ◽

pp. L466-L470 ◽

Cited By ~ 15

Author(s):

L. B. Clerch ◽

D. Massaro

Keyword(s):

Gene Expression ◽

Superoxide Dismutase ◽

Antioxidant Enzymes ◽

Manganese Superoxide Dismutase ◽

Late Gestation ◽

Postnatal Exposure ◽

Sod Activity ◽

Copper Zinc Superoxide Dismutase ◽

Manganese Superoxide ◽

Copper Zinc

The lung activity of the antioxidant enzymes (AOEs) copper, zinc superoxide dismutase (Cu,Zn SOD), catalase (CAT), and glutathione peroxidase (GP), but not manganese superoxide dismutase (Mn SOD), increases in rats during late gestation; the concentrations of Cu,Zn SOD mRNA and CAT mRNA also rise. During early postnatal exposure to > 95% O2, the lung activity of Cu,Zn SOD, CAT, and GP increases. We now show 1) the lung concentration of Mn SOD mRNA and GP mRNA does not increase in late gestation; 2) Mn SOD activity and the concentration of its mRNA and of GP mRNA increase during exposure of neonatal rats to > 95% O2; and 3) as previously shown for CAT mRNA, the increase in lung concentration of the mRNAs for Cu,Zn SOD, Mn SOD, and GP during early postnatal hyperoxia occurs with a 70–80% prolongation of the half-life of these mRNAs. We conclude that 1) in late gestation the level at which lung AOE gene expression is regulated differs among the enzymes, 2) the level at which lung AOE gene expression is regulated shortly after birth in response to > 95% O2 is uniform among the enzymes, and 3) the lung's AOE response to neonatal hyperoxia is not merely a step-up of its prenatal regulation but involves different regulatory mechanisms based on increased stability of AOE mRNAs

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Molecular cloning and characterization of the copper/zinc and manganese superoxide dismutase genes from the human parasiteClonorchis sinensis

Parasitology ◽

10.1017/s003118200400695x ◽

2005 ◽

Vol 130 (6) ◽

pp. 687-697 ◽

Cited By ~ 12

Author(s):

A. H. LI ◽

Y. KONG ◽

S. H. CHO ◽

H. W. LEE ◽

B. K. NA ◽

...

Keyword(s):

Superoxide Dismutase ◽

Manganese Superoxide Dismutase ◽

Mrna Level ◽

Clonorchis Sinensis ◽

Amino Acid Sequences ◽

Sod Activity ◽

Intronless Gene ◽

Copper Zinc Superoxide Dismutase ◽

Manganese Superoxide ◽

Copper Zinc

A copper/zinc superoxide dismutase (Cu/ZnSOD) gene and a manganese superoxide dismutase (MnSOD) gene of the human parasiteClonorchis sinensishave been cloned and their gene products functionally characterized. GenesCu/ZnSODandMnSODencode proteins of 16 kDa and 25·4 kDa, respectively. The deduced amino acid sequences of the two genes contained highly conserved residues required for activity and secondary structure formation of Cu/ZnSOD and MnSOD, respectively, and show up to 73·7% and 75·4% identities with their counterparts in other animals. The genomic DNA sequence analysis of Cu/ZnSOD gene revealed this as an intronless gene. Inhibitor studies with purified recombinant Cu/ZnSOD and MnSOD, both of which were functionally expressed inEscherichia coli, confirmed that they are copper/zinc and manganese-containing SOD, respectively. Immunoblots showed that bothC. sinensisCu/ZnSOD and MnSOD should be antigenic for humans, and both, especially theC. sinensisMnSOD, exhibit extensive cross-reactions with sera of patients infected by other trematodes or cestodes. RT-PCR and SOD activity staining of parasite lysates indicate that there are no significant differences in mRNA level or SOD activity for both species of SOD, indicating cytosolic Cu/ZnSOD and MnSOD might play a comparatively important role in theC. sinensisantioxidant system.

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Inhibition of copper/zinc superoxide dismutase impairs NO ⋅-mediated endothelium-dependent relaxations

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1999.276.3.h1043 ◽

1999 ◽

Vol 276 (3) ◽

pp. H1043-H1048 ◽

Cited By ~ 19

Author(s):

Christel O. Wambi-Kiéssé ◽

Zvonimir S. Katusic

Keyword(s):

Nitric Oxide ◽

Superoxide Dismutase ◽

Inhibitory Effect ◽

Sod Activity ◽

Nitric Oxide Synthase Inhibitor ◽

Copper Zinc Superoxide Dismutase ◽

Zinc Superoxide Dismutase ◽

A 23187 ◽

Basilar Arteries ◽

Copper Zinc

The superoxide anion ([Formula: see text]) appears to be an important modulator of nitric oxide (NO ⋅) bioavailability. The present study was designed to characterize the role of copper/zinc superoxide dismutase (Cu/Zn SOD) in endothelium-dependent relaxations. Cu/Zn SOD was inhibited with the Cu2+chelator diethyldithiocarbamic acid (DETCA). In isolated canine basilar arteries, DETCA (7.6 × 10−3 M) inhibited total vascular SOD activity by 46% ( P < 0.0001, n = 6–8 dogs). DETCA (7.6 × 10−3M) significantly reduced relaxations to bradykinin and A-23187 ( P < 0.05, n = 7–11). The inhibitory effect of DETCA was abolished by the [Formula: see text]scavenger 4,5-dihydroxy-1,3-benzenedisulfonic acid (Tiron; 9.4 × 10−3 M; P < 0.05, n = 6–13). Tiron significantly potentiated the relaxations to bradykinin in control rings ( P < 0.05, n = 13), and the nitric oxide synthase inhibitor N ω-nitro-l-arginine methyl ester (l-NAME; 3 × 10−4 M) abolished these relaxations ( P < 0.0001, n = 6). DETCA and Tiron had no effect on the relaxations to diethylamine-NONOate or forskolin ( P > 0.05, n = 6). Our results demonstrate that endothelium-dependent relaxations mediated by NO ⋅ are impaired after the inhibition of Cu/Zn SOD. Relaxations to bradykinin (but not A-23187) were significantly augmented by Tiron. Pharmacological scavenging of [Formula: see text]reverses the effect of Cu/Zn SOD inhibition.

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Superoxide dismutase and lipid hydroperoxides in blood and endometrial tissue of patients with benign, hyperplastic and malignant endometrium

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652008000300011 ◽

2008 ◽

Vol 80 (3) ◽

pp. 515-522 ◽

Cited By ~ 15

Author(s):

Snežana Pejić ◽

Ana Todorović ◽

Vesna Stojiljković ◽

Dragana Cvetković ◽

Nenad Lučić ◽

...

Keyword(s):

Superoxide Dismutase ◽

Healthy Subjects ◽

Endometrial Tissue ◽

Lipid Hydroperoxides ◽

Sod Activity ◽

Copper Zinc Superoxide Dismutase ◽

Gynecological Disorders ◽

Zinc Superoxide Dismutase ◽

Copper Zinc ◽

Therapy Target

Epidemiological and experimental data point to involvement of oxygen derived radicals in the pathogenesis of gynecological disorders, as well as in cancer development. The objective of the present study was to examine changes in activities and levels of copper/zinc superoxide dismutase (CuZnSOD) and lipid hydroperoxides (LOOH) in blood and endometrial tissue of patients diagnosed with uterine myoma, endometrial polypus, hyperplasia simplex, hyperplasia complex and adenocarcinoma endometrii. The results of our study have shown decreased SOD activities and unchanged SOD protein level in blood of all examined patients in comparison to healthy subjects. Decrease of both SOD activity and level was found in endometrium of patients with hyperplasia simplex, hyperplasia complex and adenocarcinoma in comparison to women with polypus or myoma. LOOH level was elevated in both tissues of patients with hyperplasiaor adenocarcinoma in comparison to healthy subjects or patients with benign diagnosis. Our findings suggest that the decrease in SOD activity and level, as well as the increase in LOOH level, in patients with gynecological disorders, render these patients more susceptible to oxidative damage caused by reactive oxygen species (ROS). An imbalance in ROS formation and SOD level may be important in the pathogenesis and/or perpetuation of tissue damage in gynecological patients. Since evidence suggests that SOD may be a therapy target for cancer treatment, our findings provide a basis for further research and options for clinical applications.

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Copper-zinc superoxide dismutase deficiency impairs sperm motility and in vivo fertility

Reproduction ◽

10.1530/rep-13-0229 ◽

2013 ◽

Vol 146 (4) ◽

pp. 297-304 ◽

Cited By ~ 21

Author(s):

Michael Garratt ◽

Roslyn Bathgate ◽

Simon P de Graaf ◽

Robert C Brooks

Keyword(s):

Oxidative Stress ◽

Superoxide Dismutase ◽

Sperm Motility ◽

Physiological Role ◽

Enzymatic Antioxidants ◽

Copper Zinc Superoxide Dismutase ◽

Zinc Superoxide Dismutase ◽

Copper Zinc ◽

And Function

Oxidative stress, overproduction of reactive oxygen species (ROS) in relation to defence mechanisms, is considered to be a major cause of male infertility. For protection against the deleterious effects of ROS, animals have a variety of enzymatic antioxidants that reduce these molecules to less reactive forms. The physiological role of these antioxidantsin vivohas been explored extensively through genetic inhibition of gene expression; surprisingly, many of these animals remain fertile in spite of increased oxidative stress. Copper-zinc superoxide dismutase-deficient (Sod1−/−) male mice are one such example for whichin vivofertility has been repeatedly reported as normal, although examination of fertility has consisted of simply pairing animals of the same strain and checking for litters. This is a fairly low criterion by which to assess fertility. Herein, we show thatSod1-deficient males have zero fertilisation success in sperm competition trials that pit them against wild-type males of an otherwise identical genetic background and are almost completely infertile when mated singly with females of a different genotype. We also show that various aspects of sperm motility and function are impaired inSod1-deficient mice. Testing the breeding capabilities of mice under more ecologically relevant conditions and with females of different genotypes may help reveal additional physiological causes of infertility.

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