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)

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

Oxidative stress is one of the hypotheses involved in the etiology of Alzheimer's disease (AD). Considerable attention has been focused on increasing the intracellular glutathione (GSH) levels in many neurodegenerative diseases, including AD. Pycnogenol (PYC) has antioxidant properties and stabilizes intracellular antioxidant defense systems including glutathione levels. The present study investigated the protective effects of PYC on acrolein-induced oxidative cell toxicity in cultured SH-SY5Y neuroblastoma cells. Decreased cell survival in SH-SY5Y cultures treated with acrolein correlated with oxidative stress, increased NADPH oxidase activity, free radical production, protein oxidation/nitration (protein carbonyl, 3-nitrotyrosine), and lipid peroxidation (4-hydroxy-2-nonenal). Pretreatment with PYC significantly attenuated acrolein-induced cytotoxicity, protein damage, lipid peroxidation, and cell death. A dose-response study suggested that PYC showed protective effects against acrolein toxicity by modulating oxidative stress and increasing GSH. These findings provide support that PYC may provide a promising approach for the treatment of oxidative stress-related neurodegenerative diseases such as AD.
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PMID:Protective effect of Pycnogenol in human neuroblastoma SH-SY5Y cells following acrolein-induced cytotoxicity. 1882 68

Garlic organosulphur compounds have been successfully used as redox anti-proliferative agents. In this work, we dissect the effects of diallyl disulphide (DADS) focusing on the events upstream of cell cycle arrest and apoptosis induced in neuroblastoma SH-SY5Y cells. We demonstrate that DADS is able to cause early morphological changes, cytoskeleton oxidation, microfilaments reduction and depolymerization of microtubules. These events are attenuated in cells stably overexpressing the antioxidant enzyme SOD1, suggesting that superoxide plays a crucial role in destabilizing cytoskeleton. Moreover, we evidence that the main microtubules-associated protein Tau undergoes PP1-mediated dephosphorylation as demonstrated by treatment with okadaic acid as well as by immunoreaction with anti-Tau-1 antibody, which specifically recognizes its dephosphorylated forms. Tau dephosphorylation is inhibited by the two-electron reductants NAC and GSH ester but not by SOD1. The inability of DADS to induce apoptosis in neuroblastoma-differentiated cells gives emphasis to the anti-proliferative activity of DADS, which can be regarded as a promising potent anti-neuroblastoma drug by virtue of its widespread cytoskeleton disrupting action on proliferating cells.
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PMID:Tau dephosphorylation and microfilaments disruption are upstream events of the anti-proliferative effects of DADS in SH-SY5Y cells. 1904 Apr 22

Acrolein, an unsaturated aldehydic product of lipid peroxidation, has been implicated in the pathogenesis of various neurodegenerative disorders including Parkinson's disease. However, protection against acrolein toxicity in neuronal cells via chemical upregulation of cellular aldehyde-detoxification factors has not been investigated. In this study, we have investigated the induction of glutathione (GSH), GSH S-transferase (GST), and aldose reductase (AR) by the unique nutraceutical compound 3H-1,2-dithiole-3-thione (D3T); and the protective effects of the D3T-mediated cellular defenses on acrolein-mediated toxicity in human neuroblastoma SH-SY5Y cells. Incubation of SH-SY5Y cells with D3T (10-100 microM) resulted in a marked concentration- and time-dependent induction of GSH, but not GST or AR. D3T treatment also led to increased mRNA expression of gamma-glutamylcysteine ligase (GCL), the key enzyme in GSH biosynthesis. Incubation of SH-SY5Y cells with 40 microM acrolein for 0.5 or 1 h resulted in a significant depletion of cellular GSH, which preceded the decrease of cell viability, suggesting critical involvement of GSH in acrolein-induced cytotoxicity. Pretreatment of SH-SY5Y cells with 100 microM D3T afforded a dramatic protection against acrolein-induced cytotoxicity, as assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium (MTT) reduction, lactate dehydrogenase release, as well as morphological changes. To further demonstrate the involvement of GSH in protection against acrolein-induced cytotoxicity, buthionine sulfoximine (BSO) was used to inhibit cellular GSH biosynthesis. Depletion of cellular GSH by 25 microM BSO dramatically potentiated acrolein-induced cytotoxicity. Cotreatment of SH-SY5Y cells with BSO and D3T was found to prevent the D3T-mediated GSH induction and completely reverse the cytoprotective effects of D3T on acrolein-induced toxicity. Taken together, this study demonstrates that upregulation of GSH is a predominant mechanism underlying D3T-mediated protection against acrolein-induced neurocytotoxicity.
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PMID:Upregulation of cellular glutathione by 3H-1,2-dithiole-3-thione as a possible treatment strategy for protecting against acrolein-induced neurocytotoxicity. 1907 13

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

It is well known that antioxidants containing sulfhydryl (-SH) groups are protective against the toxic effects of mercury. The current study was designed to elucidate the mechanism(s) of the cytoprotective effects of glutathione (GSH) and N-acetylcysteine (NAC) against the toxicity of inorganic mercury (HgCl(2)) in neuroblastoma cells (N-2A). The obtained results demonstrated the protective effects of these compounds in a dose dependant manner up to 95 and 74% cell viability, respectively as compared to the control of HgCl(2) of 10%. The administration of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis, increased the toxicity of HgCl(2) in a dose dependent manner. Moreover, BSO treatment attenuated the levels of the cellular free -SH concentrations at low concentrations (1-100 microM) of HgCl(2). The data also show that cellular thiol concentrations were augmented in the presence of GSH and NAC and these compounds were cytoprotective against HgCl(2) and this is due to up regulating of GSH synthesis. A reduction in intracellular levels of GSH was observed with treatment of HgCl(2). In addition, the ratio of GSH/GSSG increased from 16:1 to 50:1 from 1 to 10 microM concentration of HgCl(2.) The ratio of GSH/GSSG then decreased from 4:1 to 0.5:1 with the increase of concentration of HgCl(2) between 100 microM and 1 mM due to the collapse of the N-2A cells. It was of interest to note that the synthesis of GSH was stimulated in cells exposed to low concentration of HgCl(2) when extra GSH is available. These data support the idea that the loss of GSH plays a contributing role to the toxic effects of HgCl(2) and that inorganic mercury adversely affects viability, through altering intracellular -SH concentrations. The data further indicate that the availability of GSH to the cells may not be sufficient to provide protection against mercury toxicity and the de novo synthesis of intracellular GSH is required to prevent the damaging effects of mercury.
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PMID:The role of intracellular glutathione in inorganic mercury-induced toxicity in neuroblastoma cells. 1934 80

Astrocytes possess important roles in maintaining normal brain function and providing trophic support to the neurons. They also suffer a range of toxic insults, being a chief target of prooxidants such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-methyl-4-phenylpyridinium (MPP(+)), 6-hydroxydopamine (6-OHDA), 4-hydroxy-2-nonenal (HNE), and acrolein. Recently, we have observed that the cellular antioxidants and phase 2 enzymes can be upregulated by 3H-1,2-dithiole-3-thione (D3T), a nutraceutical found in cruciferous vegetables, against many prooxidants in human neuroblastoma cell lines (SH-SY5Y). However, the regulation of the above cellular factors by D3T in astrocytes and their role in ameliorating the neurotoxic effects of the above neurotoxins have not been investigated. In this study, we show that incubation of human primary astrocytes with micromolar concentrations (5-100 microM) of D3T for 24 h resulted in significant increases in the levels of reduced glutathione (GSH), glutathione reductase (GR), and the phase 2 enzyme NAD(P)H:quinone oxidoreductase 1 (NQO1). D3T treatment also caused time-dependent increases in mRNA expression of the gamma-glutamylcysteine ligase catalytic subunit (GCLC), GR, and of NQO1 in these cells. Pretreatment of astrocytes with D3T was found to afford remarkable protection against the neurocytotoxicity elicited by MPTP, MPP(+), 6-OHDA, HNE and acrolein. Taken together, this study demonstrates for the first time that in human astrocytes, the cruciferous nutraceutical D3T potently induces the cellular GSH system and the phase 2 enzyme NQO1, which is accompanied by dramatically increased resistance of these cells to the damage induced by various neurotoxicants. The results of this study may have important implications for the development of novel neuroprotective strategies.
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PMID:Cruciferous nutraceutical 3H-1,2-dithiole-3-thione protects human primary astrocytes against neurocytotoxicity elicited by MPTP, MPP(+), 6-OHDA, HNE and acrolein. 1940 15

Standardized extract from the leaves of the Ginkgo biloba tree, labeled EGb761, is one of the most popular herbal supplements, taken for its multivalent properties. In this study, dosage effects of EGb761 on hydrogen peroxide (H(2)O(2))-induced apoptosis of human neuroblastoma SH-SY5Y cells were investigated. It was found that H(2)O(2)-induced apoptotic cell death in SH-SY5Y cells, which was revealed in DNA fragmentation, mitochondrial membrane potential depolarization, and activation of Akt, c-Jun N-terminal kinases (JNK) and caspase 3. Low doses of EGb761 (50-100 microg/ml) inhibited H(2)O(2)-induced cell apoptosis via inactivation of Akt, JNK and caspase 3 while high doses of EGb761 (250-500 microg/ml) enhanced H(2)O(2) toxicities via inactivation of Akt and enhancement of activation of JNK and caspase 3. Additional experiments revealed that H(2)O(2) decreased intracellular GSH content, which was also inhibited by low concentrations of EGb761 but enhanced after high concentrations of EGb761 treatment. This further suggests to us that dosage effects of EGb761 on apoptotic signaling proteins may be correlated with regulation of cell redox state. Therefore, treatment dosage may be one of the vital factors that determine the specific action of EGb761 on oxidative stress-induced cell apoptosis. To understand the mechanisms of dosage effects of EGb761 may have important clinical implications.
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PMID:Dosage effects of EGb761 on hydrogen peroxide-induced cell death in SH-SY5Y cells. 1941 4

In our previous study, we found that caspase-dependent apoptosis played a role in the genesis of toxicity of acrylamide in human neuroblastoma (SH-SY5Y) cells (Sumizawa and Igisu in Arch Toxicol 81:279-282, 2007). In the present experiment, we examined whether carboxyfullerene may suppress the cytotoxicity of acrylamide because carboxyfullerene has been reported to protect nerve cells from various pathologic processes including apoptosis. Carboxyfullerene lowered lactate dehydrogense leakage and elevated cell viability in SH-SY5Y cells exposed to acrylamide. It also lowered caspase-3 activities and cell population in the sub-G(1) phase induced by acrylamide. Nevertheless, carboxyfullerene enhanced cellular uptake of [(14)C]acrylamide. On the other hand, acrylamide markedly decreased glutathione (GSH)-content in cells and carboxyfullerene blocked the decrease. The toxicity of acrylamide was suppressed by adding GSH or GSH monoethyl ester, whereas it was not lowered by carboxyfullerene when GSH synthesis was inhibited by L: -buthionine-(S,R)-sulfoximine. Thus, the cytotoxicity of acrylamide including apoptotic processes is closely related to GSH level in SH-SY5Y cells and carboxyfullerene suppresses the toxicity by maintaining GSH content. Neither tricarboxylic acids without fullerene moiety nor hydroxylated fullerene showed comparable effects of carboxyfullerene (60 microM) against 1-5 mM acrylamide, suggesting the importance of the three malonic acid groups at specific positions in a fullerene molecule for the effects.
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PMID:Suppression of acrylamide toxicity by carboxyfullerene in human neuroblastoma cells in vitro. 1947 99

Methylmercury (MeHg) is a neurotoxicant which enters the brain and may cause permanent change. Thus, the properties of MeHg transport across cell membranes are a key factor in designing an appropriate model for MeHg neurotoxicity. This study uses cell cultures to examine the uptake and efflux mechanisms of methylmercury in C6 glioma, B35 neuroblastoma and rat brain endothelial (RBE4) cells. The cellular uptake and efflux of MeHg was investigated using (14)C-labeled MeHg. The uptake of MeHg-chloride was temperature-independent while the uptake of MeHg-L-cysteine was temperature-dependent in all the three cell types. This indicates that uptake of MeHg-chloride is due to passive diffusion and uptake of MeHg-L-cysteine is due to a protein carrier. Substrates of the amino acid transport system L inhibited uptake of MeHg-L-cysteine in C6 and RBE4 cells, but not B35 cells, indicating a role for system L in MeHg-uptake in the former two. Probenecid, Na(+)-free medium, MeHg and several L-amino acids did not alter the efflux of MeHg from C6 and RBE4 cells. The amino acids L-cysteine and cystine however, increased the efflux. Both cysteine and cystine are important in the generation of glutathione (GSH), suggesting the involvement of GSH in MeHg efflux. HgCl(2) at low concentrations (0.5 and 1.0 microM) decreased the MeHg efflux and at high concentrations (5.0 and 10.0 microM) increased the efflux. This inhibiting effect of HgCl(2) at low concentrations is possibly due to binding to GSH while the effect of high HgCl(2) concentrations is attributed to disrupted membrane integrity, as measured by Trypan blue. This study demonstrates differing transport mechanisms of MeHg in the cell lines C6, B35 and RBE4.
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PMID:Uptake and efflux of methylmercury in vitro: comparison of transport mechanisms in C6, B35 and RBE4 cells. 1954 Sep 10


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