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1.  Neuroprotection from NMDA excitotoxic lesion by Cu/Zn superoxide dismutase gene delivery to the postnatal rat brain by a modular protein vector 
BMC Neuroscience  2006;7:35.
Background
Superoxide mediated oxidative stress is a key neuropathologic mechanism in acute central nervous system injuries. We have analyzed the neuroprotective efficacy of the transient overexpression of antioxidant enzyme Cu/Zn Superoxide dismutase (SOD) after excitotoxic injury to the immature rat brain by using a recently constructed modular protein vector for non-viral gene delivery termed NLSCt. For this purpose, animals were injected with the NLSCt vector carrying the Cu/Zn SOD or the control GFP transgenes 2 hours after intracortical N-methyl-D-aspartate (NMDA) administration, and daily functional evaluation was performed. Moreover, 3 days after, lesion volume, neuronal degeneration and nitrotyrosine immunoreactivity were evaluated.
Results
Overexpression of Cu/Zn SOD transgene after NMDA administration showed improved functional outcome and a reduced lesion volume at 3 days post lesion. In secondary degenerative areas, increased neuronal survival as well as decreased numbers of degenerating neurons and nitrotyrosine immunoreactivity was seen. Interestingly, injection of the NLSCt vector carrying the control GFP transgene also displayed a significant neuroprotective effect but less pronounced.
Conclusion
When the appropriate levels of Cu/Zn SOD are expressed transiently after injury using the non-viral modular protein vector NLSCt a neuroprotective effect is seen. Thus recombinant modular protein vectors may be suitable for in vivo gene therapy, and Cu/Zn SOD should be considered as an interesting therapeutic transgene.
doi:10.1186/1471-2202-7-35
PMCID: PMC1462999  PMID: 16638118
2.  Regulation of Mn-SOD Activity and Neuroprotection by STAT3 in Mice after Cerebral Ischemia 
Cerebral ischemia and reperfusion increase superoxide anions (O2•−) in brain mitochondria. Manganese superoxide dismutase (Mn-SOD; SOD2), a primary mitochondrial antioxidant enzyme, scavenges superoxide radicals and its overexpression provides neuroprotection. However, the regulatory mechanism of Mn-SOD expression during cerebral ischemia and reperfusion is still unclear. In this study, we identified the signal transducer and activator of transcription 3 (STAT3) as a transcription factor of the mouse Mn-SOD gene, and elucidated the mechanism of O2 •− overproduction after transient focal cerebral ischemia (tFCI). We found that Mn-SOD expression is significantly reduced by reperfusion in the cerebral ischemic brain. We also found that activated STAT3 is usually recruited into the mouse Mn-SOD promoter and upregulates transcription of the mouse Mn-SOD gene in the normal brain. However, at early post-reperfusion periods after tFCI, STAT3 was rapidly downregulated and its recruitment into the Mn-SOD promoter was completely blocked. In addition, transcriptional activity of the mouse Mn-SOD gene was significantly reduced by STAT3 inhibition in primary cortical neurons. Moreover, we found that STAT3 deactivated by reperfusion induces accumulation of O2 •− in mitochondria. The loss of STAT3 activity induced neuronal cell death by reducing Mn-SOD expression. Using SOD2-/+ heterozygous knock-out mice, we found that Mn-SOD is a direct target of STAT3 in reperfusion-induced neuronal cell death. Our study demonstrates that STAT3 is a novel transcription factor of the mouse Mn-SOD gene and plays a crucial role as a neuroprotectant in regulating levels of reactive oxygen species in the mouse brain.
doi:10.1523/JNEUROSCI.1110-09.2009
PMCID: PMC2712132  PMID: 19474327
STAT3; Mn-SOD; transcription; superoxide; MCAO; apoptosis
3.  Hyperglycemia-Enhanced Ischemic Brain Damage in Mutant Manganese SOD Mice Is Associated With Suppression of HIF-1α 
Neuroscience letters  2009;456(2):89-92.
Both preischemic hyperglycemia and reduction of manganese superoxide dismutase activity are known to enhance neuronal death induced by transient cerebral ischemia. Transcriptional factor Hypoxia-inducible factor 1 (HIF-1) regulates multiple downstream genes that modulate cell metabolism, survival, death, angiogenesis, hematopoiesis, and other functions. The objectives of this study were to determine (i) whether hyperglycemia is able to increase ischemic brain damage in mutant manganese superoxide dismutase (SOD2) mice and (ii) whether reduction of SOD2 activity has a profound effect on HIF-1 protein expression under hyperglycemic ischemic condition. Both wild type and mutant SOD deficient (SOD2−/+) mice were induced to hyperglycemia 30 minutes before induction of a 30-minute transient middle cerebral artery occlusion (tMCAO). Brains were extracted after 5 and 24 hours of reperfusion for immunohistochemistry and Western blot analyses. The results showed that preischemic hyperglycemia significantly increased infarct volume in SOD2−/+mice and that HIF-1α protein levels were significantly reduced in ischemic core area at 5- and 24 hrs of reperfusion in hyperglycemic SOD2−/+ mice. However, the HIF-1α protein levels were not significantly decreased in hyperglycemic wild type animals subjected to stroke. The results suggest that the increased brain damage observed in hyperglycemic SOD2−/+ mice is associated with HIF-1α suppression, while hyperglycemia per se does not seem to exert its detrimental effects on ischemic brain via modulating HIF-1 pathway.
doi:10.1016/j.neulet.2009.03.076
PMCID: PMC2680794  PMID: 19429140
Hypoxia-inducible factor; cerebral ischemia; manganese superoxide dismutase; hyperglycemia; free radicals
4.  Reperfusion and Neurovascular Dysfunction in Stroke: From Basic Mechanisms to Potential Strategies for Neuroprotection 
Molecular neurobiology  2010;41(2-3):172-179.
Effective stroke therapies require recanalization of occluded cerebral blood vessels. However, reperfusion can cause neurovascular injury, leading to cerebral edema, brain hemorrhage, and neuronal death by apoptosis/necrosis. These complications, which result from excess production of reactive oxygen species in mitochondria, significantly limit the benefits of stroke therapies. We have developed a focal stroke model using mice deficient in mitochondrial manganese-superoxide dismutase (SOD2−/+) to investigate neurovascular endothelial damage that occurs during reperfusion. Following focal stroke and reperfusion, SOD2−/+ mice had delayed blood-brain barrier breakdown, associated with activation of matrix metalloproteinase and high brain hemorrhage rates, whereas a decrease in apoptosis and hemorrhage was observed in SOD2 overexpressors. Thus, induction and activation of SOD2 is a novel strategy for neurovascular protection after ischemia/reperfusion. Our recent study identified the signal transducer and activator of transcription 3 (STAT3) as a transcription factor of the mouse SOD2 gene. During reperfusion, activation of STAT3 and its recruitment into the SOD2 gene were blocked, resulting in increased oxidative stress and neuronal apoptosis. In contrast, pharmacological activation of STAT3 induced SOD2 expression, which limits ischemic neuronal death. Our studies point to antioxidant-based neurovascular protective strategies as potential treatments to expand the therapeutic window of currently approved therapies.
doi:10.1007/s12035-010-8102-z
PMCID: PMC2877155  PMID: 20157789
Cerebral ischemia; Oxidative stress; Reactive oxygen species; Mitochondria; Mn-SOD; STAT3; NADPH oxidase; CK2; Neuroprotective signaling
5.  Superoxide Dismutase Mimics: Chemistry, Pharmacology, and Therapeutic Potential 
Antioxidants & Redox Signaling  2010;13(6):877-918.
Abstract
Oxidative stress has become widely viewed as an underlying condition in a number of diseases, such as ischemia–reperfusion disorders, central nervous system disorders, cardiovascular conditions, cancer, and diabetes. Thus, natural and synthetic antioxidants have been actively sought. Superoxide dismutase is a first line of defense against oxidative stress under physiological and pathological conditions. Therefore, the development of therapeutics aimed at mimicking superoxide dismutase was a natural maneuver. Metalloporphyrins, as well as Mn cyclic polyamines, Mn salen derivatives and nitroxides were all originally developed as SOD mimics. The same thermodynamic and electrostatic properties that make them potent SOD mimics may allow them to reduce other reactive species such as peroxynitrite, peroxynitrite-derived CO3·−, peroxyl radical, and less efficiently H2O2. By doing so SOD mimics can decrease both primary and secondary oxidative events, the latter arising from the inhibition of cellular transcriptional activity. To better judge the therapeutic potential and the advantage of one over the other type of compound, comparative studies of different classes of drugs in the same cellular and/or animal models are needed. We here provide a comprehensive overview of the chemical properties and some in vivo effects observed with various classes of compounds with a special emphasis on porphyrin-based compounds. Antioxid. Redox Signal. 13, 877–918.
Introduction
General
Antioxidants
Manganese and Mn Complexes with Simple Ligands
SOD-like activity of manganese
The effects of manganese in vitro and in vivo
Porphyrin-Based SOD Mimics
Metalloporphyrins
Design of porphyrin-based SOD mimics
Thermodynamics
Electrostatics
Anionic porphyrins, MnTBAP3− (MnTCPP3−), and MnTSPP3−
Neutral porphyrins
Stability of metalloporphyrins
Aerobic growth of SOD-deficient Escherichia coli
Bioavailability of Mn porphyrins
The effect of the length of the N-alkylpyridyl chains on in vivo efficacy of ortho isomers
The effect of the location of pyridinium nitrogens with respect to porphyrin meso position: meta vs. ortho vs. para isomeric Mn(III) N-alkylpyridylporphyrins
Mitochondrial accumulation of Mn porphyrins
Nuclear and cytosolic accumulation of Mn porphyrins
Pharmacokinetics
Intraperitoneal administration
Oral administration
Other modes of action
Superoxide reductase–like action
Peroxynitrite reducing ability
Nitrosation
Reactivity toward HOCl
Reactivity toward H2O2
Prooxidative action of Mn porphyrins
Inhibition of redox-controlled cellular transcriptional activity
The effects of Mn porphyrins in suppressing oxidative-stress injuries in vitro and in vivo
General considerations
Central nervous system injuries
Stroke
Subarachnoid hemorrhage
Spinal cord injury
Amyotrophic lateral sclerosis
Alzheimer's disease
Parkinson's disease
Cerebral palsy
Radiation injury
Cancer
Breast cancer
Skin cancer
Prostate cancer
MnTE-2-PyP5+ + chemotherapy
MnTE-2-PyP5+ + radiotherapy
MnTE-2-PyP5+ + hyperthermia
Pain therapy: prevention of chronic morphine tolerance
Diabetes
Sickle-cell disease
Cardiac injury
Other ischemia–reperfusion injuries (renal, hepatic)
Lung injuries
Osteoarthritis
Toxicity
Fe porphyrins
Ortho isomers of Fe(III) substituted pyridylporphyrins
Cu porphyrins
Co and Ni porphyrins
Porphyrin-Related Compounds: Biliverdins, Texaphyrins, and Corroles
Mn(III) biliverdin and its analogues
Texaphyrins
Corroles
Mn Salen Compounds
SOD-like activity of Mn salens
Catalase-like activity of Mn salens
Reactivity toward other ROS/RNS
Mn salens in suppressing oxidative-stress injuries in vivo
Mn Cyclic Polyamines
SOD-like activity
Mn(II) cyclic polyamines in suppressing oxidative stress in vivo and in vitro
Nonmetal-Based SOD Mimics
Fullerenes
SOD-like activity
The protective effects of fullerenes in vivo
Nitroxides
SOD-like activity of nitroxides
Reactivity toward other ROS/RNS
The protective effects of nitroxides in vitro and in vivo
Other Compounds
Comparative Studies
Conclusions
doi:10.1089/ars.2009.2876
PMCID: PMC2935339  PMID: 20095865
6.  Reduced oxidative stress promotes NF-κB-mediated neuroprotective gene expression after transient focal cerebral ischemia: lymphocytotrophic cytokines and anti-apoptotic factors 
Nuclear factor-kappa B (NF-κB) is activated by oxidative stress such as that induced by transient focal cerebral ischemia (tFCI). Whether NF-κB has a role in cell survival or death in stroke is a matter of debate. We proposed that the status of oxidative stress may determine its role in cell death or survival after focal ischemia. To characterize the coordinated expression of genes in NF-κB signaling after mild cerebral ischemia, we investigated the temporal profile of a NF-κB-pathway-focused DNA array after 30 min of tFCI in wild-type (WT) mice and human copper/zinc-superoxide dismutase transgenic (SOD1 Tg) mice that had a significantly reduced level of superoxide. Differentially expressed genes among 96 NF-κB-related genes were further confirmed and compared in the WT and SOD1 Tg mice using quantitative polymerase chain reaction, Western blotting, and immunohistochemistry. Persistent up-regulation of NF-κB seen at 7 days in the WT mice was decreased in the SOD1 Tg mice. Lymphocytotrophic cytokine genes such as interleukin-2, interleukin-12, and interferon-α1 were increased in the SOD1 Tg mice compared with the WT mice after tFCI. In addition, anti-apoptosis factors bcl-2 and tumor necrosis factor receptor-associated factor 1 rapidly increased in the SOD1 Tg mice compared with the WT mice. This study indicates that reduced oxidative stress by SOD1 overexpression increased NF-κB-related rapid defenses, such as immune response and anti-apoptosis factors, and prevented brain damage after tFCI-induced oxidative stress.
doi:10.1038/sj.jcbfm.9600379
PMCID: PMC1831759  PMID: 16868554
anti-apoptosis factor; focal cerebral ischemia; lymphocytotrophic cytokine; NF-κB signaling; oxidative stress
7.  PEP-1-SOD1 protects brain from ischemic insult following asphyxial cardiac arrest in rats 
Resuscitation  2011;82(8):1081-1086.
Aim of the study
Reperfusion following cerebral ischemia leads to overproduction of reactive oxygen species (ROS) and consumption of endogenous antioxidants. Antioxidant enzymes are considered to have beneficial effects against various diseases mediated by ROS. Cu, Zn-superoxide dismutase is one of the major means by which cells counteract the deleterious effects of ROS after ischemia. However, exogenous SOD1 can not be delivered into living cells because of the poor permeability and selectivity of the cell membrane, thus its usage for protecting cells/tissues from oxidative stress damage is greatly limited.
Methods
The purified SOD1 or purified PEP-1-SOD1 fusion proteins were injected into mice via their tail veins, the transduction ability of PEP-1-SOD1 was detected with immunofluorescence method and SOD1 activity. Moreover, we studied whether PEP-1-SOD1 can protect brain from ischemic injury in an experimental asphyxia-cardiac arrest rat model through detecting of the levels of histopathology, MDA, NSE and S100β.
Results
SOD1 protein was detected in PEP-1-SOD1-treated animals and the SOD1 activity levels were significantly increased. However, fluorescence signals were not detected in control SOD1-treated animals. The transduced PEP-1-SOD1 could significantly attenuate cerebral ischemia-reperfusion damage, inhibited ischemia-induced lipid peroxidation, and protected neurons in hippocampus from ischemic damage induced by transient global ischemic insults.
Conclusions
We propose that PEP-1-SOD1 fusion protein has potential use as a therapeutic agent against various disorders mediated by ROS and may be useful as a therapeutic agent for treating transient global cerebral ischemia.
doi:10.1016/j.resuscitation.2011.01.034
PMCID: PMC3138811  PMID: 21531066
Cardiac arrest; cerebral ischemia; cell-penetrating peptide; PEP-1; SOD1
8.  Neuroprotective effects of chloroform and petroleum ether extracts of Nigella sativa seeds in stroke model of rat 
PURPOSE:
Stroke still remains a challenge for the researchers and scientists for developing ideal drug. Several new drugs are being evaluated showing excellent results in preclinical studies but when tested in clinical trials, they failed. Many herbal drugs in different indigenous system of medicine claim to have beneficial effects but not extensively evaluated for stroke (cerebral ischemia).
AIM:
The present study was undertaken to evaluate chloroform and petroleum ether extract of Nigella sativa seeds administered at a dose of 400 mg/kg, per orally for seven days in middle cerebral artery occluded (MCAO) rats for its neuroprotective role in cerebral ischemia.
MATERIALS AND METHODS:
Focal cerebral ischemia was induced by middle cerebral artery occlusion for two hours followed by reperfusion for 22 hours. After 24 hours, grip strength, locomotor activity tests were performed in different treatment groups of rats. After completing behavioral tests, animals were sacrificed; brains were removed for the measurement of infarct volume followed by the estimation of markers of oxidative stress.
RESULTS:
Both chloroform and petroleum ether extracts-pretreated rats showed improvement in locomotor activity and grip strength, reduced infarct volume when compared with MCAO rats. MCA occlusion resulted in the elevation of levels of thiobarbituric acid reactive substance (TBARS), while a reduction in the levels of glutathione (GSH) and antioxidant enzymes viz. superoxide dismutase (SOD) and catalase levels were observed. Pre-treatment of both extracts of Nigella sativa showed reduction in TBARS, elevation in glutathione, SOD, and catalase levels when compared with MCAO rats.
CONCLUSION:
The chloroform and petroleum ether extract of Nigella sativa showed the protective effects in cerebral ischemia. The present study confirms the antioxidant, free radical scavenging, and anti-inflammatory properties of Nigella sativa already reported.
doi:10.4103/0975-7406.111825
PMCID: PMC3697190  PMID: 23833517
Chloroform; cerebral ischemia; neuroprotective effects; petroleum ether extract; Nigella sativa
9.  Protective effect of a sesamin derivative, 3-bis (3-methoxybenzyl) butane-1, 4-diol on ischemic and hypoxic neuronal injury 
Background
Stroke is one of the leading causes of neuronal death. Sesamin is known for neuroprotection by its antioxidant and anti-inflammatory properties but it lacks blood–brain barrier (BBB) activity. A panel of sesamin derivatives was screened and 3-bis (3-methoxybenzyl) butane-1,4-diol (BBD) was selected for high BBB activity and tested for its neuroprotective effect.
Methods
The focal cerebral ischemia of Sprague–Dawley rats and hypoxia models of murine BV-2 microglia or PC12 cells under oxygen/glucose deprivation were used for in vivo and in vitro test, respectively. Lipid peroxidation and superoxide dismutase (SOD) activity from the ischemic brain were tested and reactive oxygen species (ROS), cytokine production, prostaglandin (PGE2) and related signaling pathways from hypoxic cells were examined by ELISA or Western blot assay, respectively.
Results
BBD showed a protective effect when given 90 min after the focal cerebral ischemia. It also reduced lipid peroxidation and preserved SOD activity from the ischemic brain. The mechanism of BBD was further confirmed by attenuating ROS, cytokine production, and PGE2 release from hypoxic BV-2 or PC12 cells. BBD significantly reduced hypoxia-induced c-Jun N-terminal kinases (JNK) and modulated AKT-1 and caspase-3 (survival and apoptotic pathways) in BV-2 cells, and inhibited hypoxia-induced JNK and cyclooxygenase-2 activation in PC12 cells.
Conclusions
The neuroprotective effect of BBD on ischemia/hypoxia models was involved with antioxidant and anti-inflammatory effects. The result would help the development of new CNS drug for protection of ischemia/hypoxia injury.
doi:10.1186/1423-0127-21-15
PMCID: PMC3975964  PMID: 24548760
Cerebral ischemia; Hypoxia; Neuroprotection; Sesamin derivative; Membrane permeability
10.  Nuclear Localization of Human Superoxide Dismutase 1 (SOD1) and Mutant SOD1-Specific Disruption of Survival Motor Neuron Protein Complex in Transgenic Amyotrophic Lateral Sclerosis Mice 
Amyotrophic lateral sclerosis (ALS) is a fatal adult-onset neurodegenerative disease that causes degeneration of motor neurons and paralysis. Approximately 20% of familial ALS cases have been linked to mutations in the copper/zinc superoxide dismutase (SOD1) gene but it is unclear how mutations in the protein result in motor neuron degeneration. Transgenic (tg) mice expressing mutated forms of human SOD1 (hSOD1) develop clinical and pathological features similar to those of ALS. We used tg mice expressing hSOD1-G93A, hSOD1-G37R, and hSOD1-wild type to investigate a new subcellular pathology involving mutant hSOD1 protein prominently localizing to the nuclear compartment and disruption of the architecture of nuclear gems. We developed methods for extracting relatively pure cell nucleus fractions from mouse CNS tissues and demonstrate low nuclear presence of endogenous SOD1 in mouse brain and spinal cord, but prominent nuclear accumulation of hSOD1-G93A, -G37R and -wild type in tg mice. hSOD1 concentrated in nuclei of spinal cord cells, particularly motor neurons, at a young age. The survival motor neuron protein (SMN) complex is disrupted in motor neuron nuclei prior to disease onset in hSOD1-G93A and -G37R mice; age-matched hSOD1-wild type mice did not show SMN disruption despite a nuclear presence. Our data suggest new mechanisms involving hSOD1 accumulation in the cell nucleus and mutant hSOD1-specific perturbations in SMN localization with disruption of the nuclear SMN complex in the ALS model mice and suggest overlap of pathogenic mechanisms with spinal muscular atrophy.
doi:10.1097/NEN.0b013e318244b635
PMCID: PMC3432922  PMID: 22249462
Cajal body; Gemin 1; Nuclear gems; Snurportin; Spinal muscular atrophy
11.  Myocardial Protective Effect of Extracellular Superoxide Dismutase Gene Modified Bone Marrow Mesenchymal Stromal Cells on Infarcted Mice Hearts 
Theranostics  2014;4(5):475-486.
Aim: 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. METHODS & RESULTS: 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 (2x106) 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. CONCLUSION: 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.
doi:10.7150/thno.7729
PMCID: PMC3964442  PMID: 24669277
human extracellular superoxide dismutase; mesenchymal stromal cells; myocardial infarction; cell-based gene therapy; reactive oxygen species.
12.  Reduction in oxidative stress by SOD1 overexpression attenuates acute brain injury after subarachnoid hemorrhage via activation of Akt/GSK3β survival signaling 
Recent studies have revealed that oxidative stress has detrimental effects in several models of neurodegenerative diseases, including subarachnoid hemorrhage (SAH). However, how oxidative stress affects acute brain injury after SAH remains unknown. We have previously reported that overexpression of copper/zinc-superoxide dismutase (SOD1) reduces oxidative stress and subsequent neuronal injury after cerebral ischemia. In this study, we investigated the relationship between oxidative stress and acute brain injury after SAH using SOD1 transgenic (Tg) rats. SAH was produced by endovascular perforation in wild-type (Wt) and SOD1 Tg rats. Apoptotic cell death at 24 h, detected by a cell death assay, was significantly decreased in the cerebral cortex of the SOD1 Tg rats compared with the Wt rats. The mortality rate at 24 h was also significantly decreased in the SOD1 Tg rats. A hydroethidine study demonstrated that superoxide anion production after SAH was reduced in the cerebral cortex of the SOD1 Tg rats. Moreover, phosphorylation of Akt and glycogen synthase kinase-3β (GSK3β), which are survival signals in apoptotic cell death, was more enhanced in the cerebral cortex of the SOD1 Tg rats after SAH using Western blot analysis and immunohistochemistry. We conclude that reduction in oxidative stress by SOD1 overexpression may attenuate acute brain injury after SAH via activation of Akt/GSK3β survival signaling.
doi:10.1038/sj.jcbfm.9600399
PMCID: PMC1857281  PMID: 16969382
Akt; apoptosis; GSK3β; oxidative stress; SOD1; subarachnoid hemorrhage
13.  Neural Stem Cells Genetically Modified to Overexpress Cu/Zn-Superoxide Dismutase Enhance Amelioration of Ischemic Stroke in Mice 
Background and Purpose
The harsh host brain microenvironment caused by production of reactive oxygen species after ischemic reperfusion injury offers a significant challenge to survival of transplanted neural stem cells (NSCs) after ischemic stroke.
Copper/zinc-superoxide dismutase (SOD1) is a specific antioxidant enzyme that counteracts superoxide anions. Here, we have investigated whether genetic manipulation to overexpress SOD1 enhances survival of grafted stem cells and accelerates amelioration of ischemic stroke.
Methods
NSCs genetically modified to overexpress or downexpress SOD1 were administered intracerebrally 2 days after transient middle cerebral artery occlusion. Histological and behavioral tests were examined from Days 0 to 28 after stroke.
Results
Overexpression of SOD1 suppressed production of superoxide anions after ischemic reperfusion injury and reduced NSC death after transplantation. In contrast, downexpression of SOD1 promoted superoxide generation and increased oxidative stress-mediated NSC death. Transplantation of SOD1-overexpressing NSCs enhanced angiogenesis in the ischemic border zone through up-regulation of vascular endothelial growth factor. Moreover, grafted SOD1-overexpressing NSCs reduced infarct size and improved behavioral performance, compared with NSCs that were not genetically modified.
Conclusions
Our findings reveal a strong involvement of SOD1 expression in NSC survival after ischemic reperfusion injury. We propose that conferring antioxidant properties on NSCs by genetic manipulation of SOD1 is a potential approach for enhancing the effectiveness of cell transplantation therapy in ischemic stroke.
doi:10.1161/STROKEAHA.112.656900
PMCID: PMC3429712  PMID: 22713489
neural stem cell; ischemic stroke; copper/zinc-superoxide dismutase; neuroprotection
14.  The nature of antioxidant defense mechanisms: a lesson from transgenic studies. 
Environmental Health Perspectives  1998;106(Suppl 5):1219-1228.
Reactive oxygen species (ROS) have been implicated in the pathogenesis of many clinical disorders such as adult respiratory distress syndrome, ischemia-reperfusion injury, atherosclerosis, neurodegenerative diseases, and cancer. Genetically engineered animal models have been used as a tool for understanding the function of various antioxidant enzymes in cellular defense mechanisms against various types of oxidant tissue injury. Transgenic mice overexpressing three isoforms of superoxide dismutase, catalase, and the cellular glutathione peroxidase (GSHPx-1) in various tissues show an increased tolerance to ischemia-reperfusion heart and brain injury, hyperoxia, cold-induced brain edema, adriamycin, and paraquat toxicity. These results have provided for the first time direct evidence demonstrating the importance of each of these antioxidant enzymes in protecting the animals against the injury resulting from these insults, as well as the effect of an enhanced level of antioxidant in ameliorating the oxidant tissue injury. To evaluate further the nature of these enzymes in antioxidant defense, gene knockout mice deficient in copper-zinc superoxide dismutase (CuZnSOD) and GSHPx-1 have also been generated in our laboratory. These mice developed normally and showed no marked pathologic changes under normal physiologic conditions. In addition, a deficiency in these genes had no effects on animal survival under hyperoxida. However, these knockout mice exhibited a pronounced susceptibility to paraquat toxicity and myocardial ischemia-reperfusion injury. Furthermore, female mice lacking CuZnSOD also displayed a marked increase in postimplantation embryonic lethality. These animals should provide a useful model for uncovering the identity of ROS that participate in the pathogenesis of various clinical disorders and for defining the role of each antioxidant enzyme in cellular defense against oxidant-mediated tissue injury.
Images
PMCID: PMC1533365  PMID: 9788901
15.  Complement component 3 inhibition by an antioxidant is neuroprotective after cerebral ischemia and reperfusion in mice 
Journal of neurochemistry  2012;124(4):523-535.
Oxidative stress after stroke is associated with the inflammatory system activation in the brain. The complement cascade, especially the degradation products of complement component 3, is a key inflammatory mediator of cerebral ischemia. We have shown that proinflammatory complement component 3 is increased by oxidative stress after ischemic stroke in mice using DNA array. In this study, we investigated whether up-regulation of complement component 3 is directly related to oxidative stress after transient focal cerebral ischemia in mice and oxygen-glucose deprivation in brain cells. Persistent up-regulation of complement component 3 expression was reduced in copper/zinc-superoxide dismutase transgenic mice, and manganese-superoxide dismutase knockout mice showed highly increased complement component 3 levels after transient focal cerebral ischemia. Antioxidant N-tert-butyl-α-phenylnitrone treatment suppressed complement component 3 expression after transient focal cerebral ischemia. Accumulation of complement component 3 in neurons and microglia was decreased by N-tert-butyl-α-phenylnitrone, which reduced infarct volume and impaired neurological deficiency after cerebral ischemia and reperfusion in mice. Small interfering RNA specific for complement component 3 transfection showed a significant increase in brain cells viability after oxygen-glucose deprivation. Our study suggests that the neuroprotective effect of antioxidants through complement component 3 suppression is a new strategy for potential therapeutic approaches in stroke.
doi:10.1111/jnc.12111
PMCID: PMC3557607  PMID: 23199288
antioxidant; complement component 3; focal cerebral ischemia; oxidative stress
16.  Increased expression of a proline-rich Akt substrate (PRAS40) in human copper/zinc-superoxide dismutase transgenic rats protects motor neurons from death after spinal cord injury 
The serine-threonine kinase, Akt, plays an important role in the cell survival signaling pathway. A proline-rich Akt substrate, PRAS40, has been characterized, and an increase in phospho-PRAS40 (pPRAS40) is neuroprotective after transient focal cerebral ischemia. However, the involvement of PRAS40 in the cell death/survival pathway after spinal cord injury (SCI) is unclear. Liposome-mediated PRAS40 transfection was done to study whether overexpression of pPRAS40 is neuroprotective. We further examined the expression of pPRAS40 after SCI by immunohistochemistry and Western blot using copper/zinc-superoxide dismutase (SOD1) transgenic (Tg) rats and wild-type (Wt) littermates. We then examined the relationship between PRAS40 and Akt by injection of LY294002, a phosphatidylinositol 3-kinase (PI3-K) pathway inhibitor, or Akt inhibitor IV, a compound that inhibits Akt activation after SCI. Our data demonstrated that increased pPRAS40 resulted in survival of more motor neurons compared with control complementary DNA transfection. Phosphorylated PRAS40 increased in the Wt rats after SCI while there was a greater and prolonged increase in the SOD1 Tg rats.
Coimmunoprecipitation showed that binding of pPRAS40 with 14-3-3 increased 1 day after SCI in the Wt rats, while there was a significant increase in the Tg rats. The inhibitor studies showed that phospho-Akt and pPRAS40 were decreased after injection of LY294002 or Akt inhibitor IV. We conclude that an increase in pPRAS40 by transfection after SCI results in survival of motor neurons, and overexpression of SOD1 in the Tg rats results in an increase in endogenous pPRAS40 and a decrease in motor neuron death through the PI3-K/Akt pathway.
doi:10.1038/sj.jcbfm.9600501
PMCID: PMC2167854  PMID: 17457363
Akt; motor neuron; PRAS40; spinal cord injury; transfection
17.  Influence of Hyperglycemia on Oxidative Stress and MMP-9 Activation After Focal Cerebral Ischemia/Reperfusion in Rats: Relationship to Blood-Brain Barrier Dysfunction 
Background and Purpose
Hyperglycemia is linked to a worse outcome after ischemic stroke. Among the manifestations of brain damage caused by ischemia are blood-brain barrier (BBB) disruption and edema formation. Oxidative stress and matrix metalloproteinase-9 (MMP-9) activation are implicated in BBB dysfunction after ischemia/reperfusion injury. Our present study was designed to clarify the relationship among hyperglycemia, oxidative stress, and MMP-9 activation associated with BBB dysfunction after transient focal cerebral ischemia (tFCI).
Methods
We used a model of 60 minutes of middle cerebral artery occlusion on the following animals: normoglycemic wild-type rats, wild-type rats with hyperglycemia induced by streptozotocin, and human copper/zinc-superoxide dismutase (SOD1) transgenic rats with streptozotocin-induced hyperglycemia. We evaluated edema volume, Evans blue leakage, and oxidative stress, such as the carbonyl groups and oxidized hydroethidine (HEt), SOD activity, and gelatinolytic activity, including MMP-9.
Results
Hyperglycemia significantly increased edema volume and Evans blue leakage. Moreover, it enhanced the levels of the carbonyl groups, the oxidized HEt signals, and MMP-9 activity after tFCI without alteration in SOD activity. Gelatinolytic activity and oxidized HEt signals had a clear spatial relationship in the hyperglycemic rats. SOD1 overexpression reduced the hyperglycemia-enhanced Evans blue leakage and MMP-9 activation after tFCI.
Conclusions
Hyperglycemia increases oxidative stress and MMP-9 activity, exacerbating BBB dysfunction after ischemia/reperfusion injury. Superoxide overproduction may be a causal link among hyperglycemia, MMP-9 activation, and BBB dysfunction.
doi:10.1161/01.STR.0000258041.75739.cb
PMCID: PMC1828129  PMID: 17272778
hyperglycemia; oxidative stress; metalloproteinase; blood-brain barrier; cerebral ischemia
18.  Influence of Viral Vector–Mediated Delivery of Superoxide Dismutase and Catalase to the Hippocampus on Spatial Learning and Memory During Aging 
Antioxidants & Redox Signaling  2012;16(4):339-350.
Abstract
Aims: Studies employing transgenic mice indicate that overexpression of superoxide dismutase 1 (SOD1) improves memory during aging. It is unclear whether the improvement is due to a lifetime of overexpression, decreasing the accumulation of oxidized molecules, or if increasing antioxidant enzymes in older animals could reduce oxidative damage and improve cognitive function. We used adeno-associated virus to deliver antioxidant enzymes (SOD1, SOD2, catalase [CAT], and SOD1+CAT) to the hippocampus of young (4 months) and aged (19 months) F344/BN F1 male rats and examined memory-related behavioral performance 1 month and 4 months postinjection. Results: Overexpression of antioxidant enzymes reduced oxidative damage; however, memory function was not related to the level of oxidative damage. Increased expression of SOD1, initiated in advanced age, impaired learning. Increased expression of SOD1+CAT provided protection from impairments associated with overexpression of SOD1 alone and appears to guard against cognitive impairments in advanced age. Innovation: Viral vector gene delivery provides a novel approach to test the hypothesis that increased expression of antioxidant enzymes, specifically in hippocampal neurons, will provide protection from age-related cognitive decline. Further, expression of multiple vectors permits more detailed investigation of mechanistic pathways. Conclusion: Oxidative stress is a likely component of aging; however, it is unclear whether increased production of reactive oxygen species or the accumulation of oxidative damage is the primary cause of functional decline. The results provide support for the idea that altered redox-sensitive signaling rather than the accumulation of damage may be of greater significance in the emergence of age-related learning and memory deficits. Antioxid. Redox Signal. 16, 339–350.
doi:10.1089/ars.2011.4054
PMCID: PMC3246419  PMID: 21942371
19.  Molecular Chaperone Mediated Late-Stage Neuroprotection in the SOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis 
PLoS ONE  2013;8(8):e73944.
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 SOD1G93A 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 SOD1G93A 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 SOD1G93A 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.
doi:10.1371/journal.pone.0073944
PMCID: PMC3758296  PMID: 24023695
20.  Evaluation of Antioxidant and Cerebroprotective Effect of Medicago sativa Linn. against Ischemia and Reperfusion Insult 
Antioxidants have been the focus of studies for developing neuroprotective agents to be used in the therapy for stroke, which is an acute and progressive neurodegenerative disorder. Medicago sativa (MS) has a long tradition of use as ayurvedic and homoeopathic medicine in central nervous system disorders. The plant has been reported to have antioxidant, anti-inflammatory and antidiabetic effects. Therefore, the present study was designed to investigate the neuroprotective effect of methanol extract of MS on ischemia and reperfusion-induced cerebral injury in mice. Bilateral carotid artery occlusion (BCAO) for 15 min followed by 24-h reperfusion, resulted in significant elevation in infarct size, xanthine oxidase (XO) activity, superoxide anion (O•−2) production and thiobarbituric acid-reactive substance (TBARS) levels, and significant depletion in endogenous antioxidant [reduced glutathione (GSH), superoxide dismutase (SOD) and total tissue sulfhydryl (T-SH) groups] systems in mice brain. Further, BCAO led to impairment in short-term memory and motor coordination. Pre-treatment with MS (100 or 200 mg kg−1, p.o.) markedly reduced cerebral infarct size, XO, O•−2 and TBARS levels, significantly restored GSH, SOD and T-SH levels and attenuated impairment in short-term memory and motor coordination. In addition, MS directly scavenged free radicals generated against a stable radical 1,1-diphenyl-2-picrylhydrazyl and O•−2 generated in phenazine methosulphate-nicotinamide adenine dinucleotide systems, and also inhibited XD/XO conversion and resultant O•−2 production. The data from this study suggest that treatment with MS enhances the antioxidant defense against BCAO-induced global cerebral ischemia and exhibits neuroprotective activity.
doi:10.1093/ecam/neq019
PMCID: PMC3137587  PMID: 21785631
21.  Heat shock factor 1 over-expression protects against exposure of hydrophobic residues on mutant SOD1 and early mortality in a mouse model of amyotrophic lateral sclerosis 
Background
Mutations in the Cu/Zn superoxide dismutase gene (SOD1) are responsible for 20% of familial forms of amyotrophic lateral sclerosis (ALS), and mutant SOD1 has been shown to have increased surface hydrophobicity in vitro. Mutant SOD1 may adopt a complex array of conformations with varying toxicity in vivo. We have used a novel florescence-based proteomic assay using 4,4’-bis-1-anilinonaphthalene-8-sulfonate (bisANS) to assess the surface hydrophobicity, and thereby distinguish between different conformations, of SOD1and other proteins in situ.
Results
Covalent bisANS labeling of spinal cord extracts revealed that alterations in surface hydrophobicity of H46R/H48Q mutations in SOD1 provoke formation of high molecular weight SOD1 species with lowered solubility, likely due to increased exposure of hydrophobic surfaces. BisANS was docked on the H46R/H48Q SOD1 structure at the disordered copper binding and electrostatic loops of mutant SOD1, but not non-mutant WT SOD1. 16 non-SOD1 proteins were also identified that exhibited altered surface hydrophobicity in the H46R/H48Q mutant mouse model of ALS, including proteins involved in energy metabolism, cytoskeleton, signaling, and protein quality control. Heat shock proteins (HSPs) were also enriched in the detergent-insoluble fractions with SOD1. Given that chaperones recognize proteins with exposed hydrophobic surfaces as substrates and the importance of protein homeostasis in ALS, we crossed SOD1 H46R/H48Q mutant mice with mice over-expressing the heat shock factor 1 (HSF1) transcription factor. Here we showed that HSF1 over-expression in H46R/H48Q ALS mice enhanced proteostasis as evidenced by increased expression of HSPs in motor neurons and astrocytes and increased solubility of mutant SOD1. HSF1 over-expression significantly reduced body weight loss, delayed ALS disease onset, decreases cases of early disease, and increased survival for the 25th percentile in an H46R/H48Q SOD1 background. HSF1 overexpression did not affect macroautophagy in the ALS background, but was associated with maintenance of carboxyl terminus of Hsp70 interacting protein (CHIP) expression which declined in H46R/H48Q mice.
Conclusion
Our results uncover the potential importance of changes in protein surface hydrophobicity of SOD1 and other non-SOD1 proteins in ALS, and how strategies that activate HSF1 are valid therapies for ALS and other age-associated proteinopathies.
doi:10.1186/1750-1326-8-43
PMCID: PMC3907013  PMID: 24256636
Aggregation; Amyotrophic lateral sclerosis; Protein surface hydrophobicity; Superoxide dismutase; Heat shock factor 1
22.  Zingiber officinale Mitigates Brain Damage and Improves Memory Impairment in Focal Cerebral Ischemic Rat 
Cerebral ischemia is known to produce brain damage and related behavioral deficits including memory. Recently, accumulating lines of evidence showed that dietary enrichment with nutritional antioxidants could reduce brain damage and improve cognitive function. In this study, possible protective effect of Zingiber officinale, a medicinal plant reputed for neuroprotective effect against oxidative stress-related brain damage, on brain damage and memory deficit induced by focal cerebral ischemia was elucidated. Male adult Wistar rats were administrated an alcoholic extract of ginger rhizome orally 14 days before and 21 days after the permanent occlusion of right middle cerebral artery (MCAO). Cognitive function assessment was performed at 7, 14, and 21 days after MCAO using the Morris water maze test. The brain infarct volume and density of neurons in hippocampus were also determined. Furthermore, the level of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in cerebral cortex, striatum, and hippocampus was also quantified at the end of experiment. The results showed that cognitive function and neurons density in hippocampus of rats receiving ginger rhizome extract were improved while the brain infarct volume was decreased. The cognitive enhancing effect and neuroprotective effect occurred partly via the antioxidant activity of the extract. In conclusion, our study demonstrated the beneficial effect of ginger rhizome to protect against focal cerebral ischemia.
doi:10.1155/2011/429505
PMCID: PMC3010628  PMID: 21197427
23.  Genetic and pharmacologic manipulation of oxidative stress after neonatal hypoxia-ischemia 
Oxidative stress is a critical component of the injury response after hypoxia-ischemia (HI) in the neonatal brain, and this response is unique and at times paradoxical to that seen in the mature brain. Previously, we showed that copper-zinc superoxide-dismutase (SOD1) over-expression is not beneficial to the neonatal mouse brain with HI injury, unlike the adult brain with ischemic injury. However, glutathione peroxidase1 (GPx1) over-expression is protective to the neonatal mouse brain with HI injury. To further test the hypothesis that an adequate supply of GPx is critical to protection from HI injury, we crossed SOD1 over-expressing mice (hSOD-tg) with GPx1 over-expressing mice (hGPx-tg). Resulting litters contained wild-type (wt), hGPx-tg, hSOD-tg and hybrid hGPx-tg/hSOD-tg pups, which were subjected to HI at P7. Confirming previous results, the hGPx-tg mice had reduced injury compared to both Wt and hSOD-tg littermates. Neonatal mice over-expressing both GPx1 and SOD1 also had less injury compared to wt or hSOD-tg alone. A result of oxidative stress after neonatal HI is a decrease in the concentration of reduced (i.e. antioxidant-active) glutathione (GSH). In this study, we tested the effect of systemic administration of alpha-lipoic acid on levels of GSH in the cortex after HI. Although GSH levels were restored by 24h after HI, injury was not reduced compared to vehicle-treated mice. We also tested two other pharmacological approaches to reducing oxidative stress in hSOD-tg and wild-type littermates. Both the specific inhibitor of neuronal nitric oxide synthase, 7-nitroindazole (7NI), and the spin-trapping agent alpha-phenyl-tert-butyl-nitrone (PBN) did not reduce HI injury, however. Taken together, these results imply that H2O2 is a critical component of neonatal HI injury, and GPx1 plays an important role in the defense against this H2O2 and is thereby neuroprotective.
doi:10.1016/j.ijdevneu.2007.08.010
PMCID: PMC2703481  PMID: 17935927
oxidative stress; stroke; reactive oxygen species; nitric oxide; hydrogen peroxide; brain; mouse
24.  Rescue of Neurons from Ischemic Injury by Peroxisome Proliferator-Activated Receptor-γ Requires a Novel Essential Cofactor LMO4 
Activation of peroxisome proliferator-activated receptor-γ (PPARγ) signaling after stroke may reduce brain injury, but this effect will depend on the levels of receptor and cofactors. Here, we showed that the direct effect of PPARγ signaling to protect neurons from ischemic injury requires a novel cofactor LMO4, because this effect was lost in LMO4-null cortical neurons. PPARγ agonist also failed to reduce cerebral infarction after transient focal ischemia in CaMKIIαCre/LMO4loxP mice with LMO4 ablated in neurons of the forebrain. Expressing LMO4 in LMO4-null cortical neurons rescued the PPARγ-protective effect. PPARγ signaling activates the promoter of the antioxidant gene SOD2 and this process requires LMO4. Addition of a superoxide dismutase mimetic MnTBAP [manganese(III)tetrakis(4-benzoic acid)porphyrin] bypassed the deficiency in PPARγ signaling and was able to directly rescue LMO4-null cortical neurons from ischemic injury. Like LMO4, PPARγ and PGC1α (PPARγ coactivator 1α) levels in neurons are elevated by hypoxic stress, and absence of LMO4 impairs their upregulation. Coimmunoprecipitation and mammalian two-hybrid assays revealed that LMO4 interacts in a ligand-dependent manner with PPARγ. LMO4 augments PPARγ-dependent gene activation, in part, by promoting RXRα (retinoid X receptor-α) binding to PPARγ and by increasing PPARγ binding to its target DNA sequence. Together, our results identify LMO4 as an essential hypoxia-inducible cofactor required for PPARγ signaling in neurons. Thus, upregulation of LMO4 expression after stroke is likely to be an important determinant of neuron survival.
doi:10.1523/JNEUROSCI.2897-08.2008
PMCID: PMC2954187  PMID: 19020036 CAMSID: cams327
LMO4; PPARγ; stroke; excitotoxicity; hypoxia; SOD2
25.  Oxidative Stress in Ischemic Brain Damage: Mechanisms of Cell Death and Potential Molecular Targets for Neuroprotection 
Antioxidants & Redox Signaling  2011;14(8):1505-1517.
Abstract
Significant amounts of oxygen free radicals (oxidants) are generated during cerebral ischemia/reperfusion, and oxidative stress plays an important role in brain damage after stroke. In addition to oxidizing macromolecules, leading to cell injury, oxidants are also involved in cell death/survival signal pathways and cause mitochondrial dysfunction. Experimental data from laboratory animals that either overexpress (transgenic) or are deficient in (knock-out) antioxidant proteins, mainly superoxide dismutase, have provided strong evidence of the role of oxidative stress in ischemic brain damage. In addition to mitochondria, recent reports demonstrate that NADPH oxidase (NOX), an important pro-oxidant enzyme, is also involved in the generation of oxidants in the brain after stroke. Inhibition of NOX is neuroprotective against cerebral ischemia. We propose that superoxide dismutase and NOX activity in the brain is a major determinant for ischemic damage/repair and that these major anti- and pro-oxidant enzymes are potential endogenous molecular targets for stroke therapy. Antioxid. Redox Signal. 14, 1505–1517.
doi:10.1089/ars.2010.3576
PMCID: PMC3061196  PMID: 20812869

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