Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glutathione (GSH) depletion is widely used to sensitize cells to anticancer treatment inducing the progression of programmed cell death and overcoming chemoresistance. It has been reported that neuroblastoma cells with MYCN amplification are unable to start TRAIL-dependent death and MYCN, in concert with cytotoxic drugs, efficiently induces the mitochondrial pathway of apoptosis through oxidative mechanisms. In this study, we show that GSH loss induced by L-buthionine-S,R-sulfoximine (BSO), an inhibitor of GSH biosynthesis, leads to overproduction of reactive oxygen species (ROS) and triggers apoptosis of MYCN-amplified neuroblastoma cells. BSO susceptibility of SK-N-BE-2C, a representative example of MYCN-amplified cells, has been attributed to stimulation of total SOD activity in the absence of changes in the level and the activity of catalase. Therefore, the unbalanced intracellular redox milieu has been demonstrated to be critical for the progression of neuroblastoma cell death that was efficiently prevented by antioxidants and rottlerin. These results describe a novel pathway of apoptosis dependent on ROS formation and PKC-delta activation and independent of p53, bcl-2, and bax levels; the selective redox modulation of PKC-delta might be suggested as a potential strategy for sensitizing MYCN-amplified cells to therapeutic approaches.
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PMID:Mechanisms of BSO (L-buthionine-S,R-sulfoximine)-induced cytotoxic effects in neuroblastoma. 1799 46

We have studied the effects of superoxide production after Cu,Zn superoxide dismutase (SOD1) down-regulation by RNA interference. We demonstrated that SOD1 depletion induced, only in neuroblastoma cells, a decrease in actin and beta-tubulin content and accumulation of neurofilament light chain and Tau proteins. Alterations of cell morphology and the microfilament network were also observed, together with the up-regulation of the Cdk5/p35 pathway, which is involved in the regulation of actin polymerization. The decrease of filamentous actin was transient and was recovered through the activation of p38/Hsp27 MAPK pathway, as well as after treatment with N-acetyl-L-cysteine. The importance of p38 in the recovery of cytoskeleton was confirmed by experiments carried out in the presence of its inhibitor SB203580, which induced cell death. Our data demonstrate that SOD1 is essential for the preservation of cytoskeleton integrity, by maintaining physiological concentration of reactive oxygen species and inhibiting the activation of the neuronal specific Cdk5/p35 pathway.
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PMID:Transient cytoskeletal alterations after SOD1 depletion in neuroblastoma cells. 1823 50

We investigated the effect of Spirulina platensis protean extract and the biliprotein phycocyanin isolated from this microalga, on the activities of the antioxidant enzymes SOD, CAT, GPx, and GR, lipid peroxidation inhibitory activity and glutathione levels after the iron induced oxidative stress in SH-SY5Y neuroblastoma cells. Iron is one of the most important agents that produce oxidative stress and decline of neuronal functions. S. platensis protean extract and phycocyanin exert the antioxidant activity by protecting the activity of the cellular antioxidant enzymes total GPx, GPx-Se and GR and by increasing reduced glutathione in cells against oxidative stress induced by iron. These results suggested that S. platensis protean extract is a powerful antioxidant through a mechanism related to antioxidant activity, capable of interfering with radical-mediated cell death. S. platensis may be useful in diseases known to be aggravated by reactive oxygen species and in the development of novel treatments for neurodegenerative disorders as long as iron has been implicated in the neuropathology of several neurodegenerative disorders such as Alzheimer's or Parkinson diseases.
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PMID:Neuroprotection by Spirulina platensis protean extract and phycocyanin against iron-induced toxicity in SH-SY5Y neuroblastoma cells. 1857 79

In order to examine the effects of alpha3 nicotinic acetylcholine receptor (nAChR) in connection with the pathogenesis of Alzheimer's disease (AD), neuroblastoma (SH-SY5Y) cells were transfected with small interference RNAs (siRNAs) that target specifically towards alpha3 nAChR. The expressions of alpha3 nAChR mRNA and protein were measured by real-time PCR and Western blotting, respectively. The levels of the alpha-form of secreted amyloid precursor protein (alphaAPPs) and total-APP were determined by Western blotting. SH-SY5Y cells transfected with siRNA were then treated with 1muM beta-amyloid peptide (Abeta)(1-42), following which the levels of lipid peroxidation, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the reduction rate of MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] were characterized by utilizing spectrophotometric procedures. As compared to controls, SH-SY5Y cells transfected with siRNA expressed the decreases in the levels of alpha3 nAChR mRNA and protein by 98% and 66% lower levels, respectively; exhibited reduced level of the alphaAPPs; and demonstrated enhanced lipid peroxidation, decreased rate of MTT reduction, and declined activities of SOD and GSH-Px. Inhibited gene expression of the alpha3 nAChR enhanced the toxicity exerted by Abeta. These results indicate that alpha3 nAChR may improve cleavage of APP by alpha-secretase, enhance antioxidation and inhibit the toxicity of Abeta, suggesting that the receptor might play an important role in AD.
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PMID:Inhibiting gene expression of alpha3 nicotinic receptor in SH-SY5Y cells with the effects on APP metabolism and antioxidation in Alzheimer's disease. 1864 33

The cellular prion protein (PrP(c)) plays a crucial role in the pathogenesis of prion diseases, but its physiological function is far from understood. Several candidate functions have been proposed including binding and internalization of metal ions, a superoxide dismutase-like activity, regulation of cellular antioxidant activities, and signal transduction. The transmembrane (TM1) region of PrP(c) (residues 110-135) is particularly interesting because of its very high evolutionary conservation. We investigated a possible role of TM1 in the antioxidant defense, by assessing the impact of overexpressing wt-PrP or deletion mutants in N(2)A mouse neuroblastoma cells on intracellular reactive oxygen species (ROS) levels. Under conditions of oxidative stress, intracellular ROS levels were significantly lowered in cells overexpressing either wild-type PrP(c) (wt-PrP) or a deletion mutant affecting TM1 (Delta8TM1-PrP), but, as expected, not in cultures overexpressing a deletion mutant lacking the octapeptide region (Deltaocta-PrP). Overexpression of wt-PrP, Delta8TM1-PrP, or Deltaocta-PrP did not affect basal ROS levels. Interestingly, the mitochondrial membrane potential was significantly lowered in Deltaocta-PrP-transfected cultures in the absence of oxidative stress. We conclude that the protective effect of PrP(c) against oxidative stress involves the octarepeat region but not the TM1 domain nor the high-affinity copper binding site described for human residues His96/His111.
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PMID:The octarepeat region of prion protein, but not the TM1 domain, is important for the antioxidant effect of prion protein. 1882 94

The uptake of ascorbate by neuroblastoma cells using a ruthenium oxide hexacyanoferrate (RuOHCF)-modified carbon fiber disc (CFD) microelectrode (r = 14.5 microm) was investigated. By use of the proposed electrochemical sensor the amperometric determination of ascorbate was performed at 0.0 V in minimum essential medium (MEM, pH = 7.2) with a limit of detection of 25 micromol L(-1). Under the optimum experimental conditions, no interference from MEM constituents and reduced glutathione (used to prevent the oxidation of ascorbate during the experiments) was noticed. The stability of the RuOHCF-modified electrode response was studied by measuring the sensitivity over an extended period of time (120 h), a decrease of around 10% being noticed at the end of the experiment. The rate of ascorbate uptake by control human neuroblastoma SH-SY5Y cells, and cells transfected with wild-type Cu,Zn-superoxide dismutase (SOD WT) or with a mutant typical of familial amyotrophic lateral sclerosis (SOD G93A), was in agreement with the level of oxidative stress in these cells. The usefulness of the RuOHCF-modified microelectrode for in vivo monitoring of ascorbate inside neuroblastoma cells was also demonstrated.
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PMID:Continuous monitoring of ascorbate transport through neuroblastoma cells with a ruthenium oxide hexacyanoferrate modified microelectrode. 1893 40

Antipsychotics are known to alter antioxidant activities in vivo. Therefore, the aim of the present study was to examine in the human neuroblastoma SH-SY5Y cell line the impact of a typical (haloperidol) and an atypical (quetiapine) antipsychotic on the expression of genes encoding the key enzymes of the antioxidant metabolism (Cu, Zn superoxide dismutase; Mn superoxide dismutase; glutathione peroxidase; catalase) and enzymes of the glutathione metabolism (gamma-glutamyl cysteine synthetase, glutathione-S-transferase, gamma-glutamyltranspeptidase, glutathione reductase). The cells were incubated for 24h with 0.3, 3, 30 and 300microM haloperidol and quetiapine, respectively; mRNA levels were measured by polymerase chain reaction. In the present study, we observed mostly significant decreases of mRNA contents. With respect to the key pathways, we detected mainly effects on the mRNA levels of the hydrogen peroxide detoxifying enzymes. Among the enzymes of the glutathione metabolism, glutathione-S-transferase- and gamma-glutamyltranspeptidase-mRNA levels showed the most prominent effects. Taken together, our results demonstrate a significantly reduced expression of genes encoding for antioxidant enzymes after treatment with the antipsychotics, haloperidol and quetiapine.
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PMID:Impact of haloperidol and quetiapine on the expression of genes encoding antioxidant enzymes in human neuroblastoma SH-SY5Y cells. 1910 87

During over 50 years of my career in Neuropathology at Montefiore Medical Center in New York, I have come across certain interesting neuropathological findings. In this communication, some photographs showing macroscopic, microscopic and electron microscopic significant findings are selected to illustrate the usefulness, not only for the diagnosis but also for the understanding of the nervous system. The 11 topics presented in this paper are: (1) alteration of dura mater associated with advanced aging; (2) orderly arrangement of tumor cells in leptomeningeal carcinomatosis; (3) horizontal section of brain with border zone infarct; (4) neurofibrillary tangle formation in the nucleus basalis Meynert ipsilateral to a massive cerebral infarct; (5) extracellular spread of hematogenous edema fluid in the white matter: (6) unrolled myelin sheath: (7) unattached presynaptic terminals in cerebellar neuroblastoma: (8) unattached post synaptic terminals in agranular cerebellar degeneration: (9) neurofibrillary tangles and Lewy bodes in a single neuron: (10) Cu/Zu superoxide dismutase positive Lewy body-like hyaline inclusions in anterior horn cells in familial motor neuron disease: (11) Hirano body. Analysis of these findings are presented for an educational purpose.
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PMID:[Neuropathological perspective on single slide]. 1919 88

The mechanisms of catechol-induced cytotoxicity were studied in cultures of neuroblastoma N2a cells. The minimal cytotoxic concentration after 72 h was 20 micromol x l(-1). The EC50 after 72 h was 38 micromol x l(-1). There was not a correlation between the cytotoxicity and the formation of quinones in the medium. Catechol-induced cytotoxicity was increased significantly when superoxide dismutase (SOD) was added. The addition of catalase did not protect cells, but this enzyme reverted the deleterious effect of SOD. The experimental studies showed a detrimental effect of deferoxamine on catechol-induced cytotoxicity suggesting that cells need iron to maintain its metabolism. NF-kappaB inhibitors increased the cytotoxicity, suggesting that this factor is also important for cell viability. L-cysteine and N-acetyl-L-cysteine protected cells significantly in a dose-dependent manner. The use of monochlorobimane showed that catechol induced reduced glutathione (GSH) depletion after 24 h, prior to cell death. The mode of cell death was studied by flow cytometry after double staining with annexin V and propidium iodide. Catechol induced apoptosis after 72 h. Furthermore, catechol also induced nuclear fragmentation. These data showed that catechol-induced cytotoxicity to N2a cell was not directly a consequence of reactive oxygen species production. Rather, it was due to GSH depletion followed by the induction of apoptosis.
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PMID:Cytotoxic effects of catechol to neuroblastoma N2a cells. 1920 5

Recent evidence suggests that some atypical antipsychotic drugs may protect against oxidative stress and consequent neurodegeneration by mechanisms that remain unclear. Using the neuron-like rat pheochromocytoma (PC-12) cell line, Clozapine and N-desmethylclozapine were tested for their ability to protect against cell death due to oxidative stress induced by hydrogen peroxide (H(2)O(2)). These drugs demonstrated significant protection of PC-12 cells, as measured by both the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide (MTT) and Alamar Blue cell viability assays. However, neither viability assay detected a protective effect of Clozapine on human embryonic kidney (HEK293), rat primary cortical neurons, or human neuroblastoma (SH-SY5Y) exposed to H(2)O(2) treatment. The mechanism of protection involves a PC-12 cell-specific differential response to H(2)O(2) treatment vs. the other cell lines. Pre-treatment with 250 microM or 125 microM diethyldithiocarbamate (DETC), a superoxide dismutase (SOD) inhibitor, unexpectedly showed protection of the PC-12 cells from H(2)O(2) treatment. Western blots revealed that Clozapine, N-desmethylclozapine, and DETC reduce the phosphorylation of extracellular signal-regulated kinase (ERK) that is caused by H(2)O(2) exposure in PC-12 cells. In both HEK293 and SH-SY5Y cells, H(2)O(2) exposure did not increase ERK phosphorylation over control, demonstrating a different response to H(2)O(2) vs. PC-12 cells, and explaining why Clozapine could not protect these cells. Also, U0126, a specific MEK inhibitor, was able to protect PC-12 cells from H(2)O(2) exposure, showing that inhibiting ERK phosphorylation is sufficient to provide protection. Cumulatively, these results indicate that Clozapine, N-desmethylclozapine, DETC, and U0126 protect PC-12 cells by blocking the cell-type specific H(2)O(2) induced increase in ERK phosphorylation.
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PMID:Clozapine protects PC-12 cells from death due to oxidative stress induced by hydrogen peroxide via a cell-type specific mechanism involving inhibition of extracellular signal-regulated kinase phosphorylation. 1950 Oct 68


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