Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of platelet-derived growth factor (PDGF) on phospholipase D (PLD) activity and deoxyribonucleic acid (DNA) synthesis in rat C6 glioma cells have been investigated. Pretreatment of serum-starved C6 cells with PDGF results in enhanced choline production and the phosphatidylethanol (PEt) formation in the presence of ethanol, indicating the activation of PLD acting on phosphatidylcholine (PC). The dose-response curve for choline generation and DNA synthesis were comparable. In addition, the effects of PDGF on both PEt formation and [3H]thymidine incorporation into acid-precipitable material was blocked by the potent protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) but not by N-(2-guanidinoethyl)-5-isoquinolinesulphonamide (HA1004), a relatively weak inhibitor of PKC, suggesting that PDGF plays an important role as a positive regulator of glioma cell growth via a PLD-mediated mitogenic signal transduction cascades, which depends largely on the activation of PKC.
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PMID:Activation of phospholipase D by platelet-derived growth factor (PDGF) in rat C6 glioma cells: possible role in mitogenic signal transduction. 136 54

The present study reports on the development of a model for maintaining constant ethanol concentrations over time in cell culture media. When neuroblastoma x glioma cells (NG 108-15) were grown in ethanol containing media under standard cultivation conditions in the incubator at 37 degrees C, a 90% evaporation was observed after 24 hr. To counteract evaporation, the cell culture dishes were placed inside polystyrene boxes together with an open dish containing an appropriate amount of ethanol. By using such procedure, the decrease in ethanol concentration in the culture media was completely avoided. Cultivating cells in ethanol-free media inside sealed plastic boxes did not change their viability, growth rate, protein and phospholipid composition of the cells or the pH of the media, compared to cultures grown outside the boxes.
Alcohol Alcohol 1992 May
PMID:A method for maintaining constant ethanol concentrations in cell culture media. 144 66

Maternal consumption of ethanol produces a pattern of malformations, including nervous system abnormalities, in the developing fetus, a state called Fetal Alcohol Syndrome. We report the dose-dependent inhibition by ethanol of the growth of a glioma derived cell line, C6 cells; the effects occur at ethanol concentrations commonly encountered in the blood during human intoxication. The effects occur with different morphological subtypes of the cell line and do not occur when the cells are exposed to iso-osmolar concentrations of other chemicals. The results demonstrate that C6 cells are a model for the study of the effects of ethanol on nervous system cell growth.
Alcohol Clin Exp Res 1992 Aug
PMID:Ethanol inhibits C6 cell growth: fetal alcohol syndrome model. 153 Jan 31

Alcohol metabolism in the human brain has been characterized as essentially nonoxidative in nature, with the esterification of ethanol with fatty acids via fatty acid ethyl ester synthase. This pathway of ethanol metabolism is related to end organ damage in the brain but the neural cell type expressing FAEES has not been identified. In this study human and rodent neuroblastoma and glioma cell lines are assayed for fatty acid ethyl ester synthase activity. Cells with neuronal properties demonstrated higher activity than glioma cell lines. We confirmed the presence of the mRNA for one type of synthase, fatty acid ethyl ester synthase-III in three neuronal cell lines--N1E115 cells, PC12 cells, and SK-N-MC cells. These results support the hypothesis that FAEES activity is expressed chiefly in cells with neuronal properties and suggest that non-oxidative ethanol metabolism is potentially related to the toxic effect of ethanol on the human brain.
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PMID:Nonoxidative ethanol metabolism: expression of fatty acid ethyl ester synthase-III in cultured neural cells. 162 45

The radiochemical syntheses of methyl 2-[123I]-iodoisonicotinate, 2-[123I]-iodoisonicotinic acid hydrazide and 2-[124I]-iodoisonicotinic acid hydrazide was accomplished. Iodine-123 was incorporated in the methyl ester molecule by an exchange reaction in glacial acetic acid. The average efficiency of iodine exchange reaction was (92.6 +/- 4.5)%. This radiotracer was extracted with ether and the solvent was evaporated. The residue was re-dissolved in anhydrous ethanol and treated with hydrazine under anhydrous conditions to obtain 2-[123I]-iodoisonicotinic acid hydrazide. The overall radiochemical yield was 69%. Biodistribution data of both radio-tracers in male Sprague-Dawley rats were collected. This is the first report of SPECT radiopharmaceuticals which may be useful for differential diagnosis of intracranial masses (tuberculoma vs glioma), and CNS tuberculosis in immunosuppressed subjects.
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PMID:Synthesis of 2-[123I and 124I]-iodoisonicotinic acid hydrazide--potential radiotracers for tuberculosis. 164 81

Exposure to ethanol for several days increases the number and function of dihydropyridine-sensitive Ca2+ channels in excitable tissues. In the neural cell line PC12, this process is blocked by inhibitors of protein kinase C (PKC), suggesting that PKC mediates ethanol-induced increases in Ca2+ channels. We report that treatment with 25-200 mM ethanol for 2-8 days increased PKC activity in PC12 cells and NG108-15 neuroblastoma-glioma cells. Detailed studies in PC12 cells showed that ethanol also increased phorbol ester binding and immunoreactivity to PKC delta and PKC epsilon. These changes were associated with increased PKC-mediated phosphorylation. Ethanol did not activate the enzyme directly, nor did ethanol increase levels of diacylglycerol. Ethanol-induced increases in PKC levels may promote up-regulation of Ca2+ channels, and may also regulate the expression and function of other proteins involved in cellular adaptation to ethanol.
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PMID:Chronic ethanol exposure increases levels of protein kinase C delta and epsilon and protein kinase C-mediated phosphorylation in cultured neural cells. 174 36

The effect of continuous and intermittent ethanol exposure on the phospholipid composition of Neuroblastoma x Glioma (NG 108-15) cell membranes was investigated. The cells were treated with ethanol for three weeks. Continuous ethanol exposure (150 mM) produced an increase (27%) in the amount of phosphatidylcholine, whereas intermittent ethanol treatment (150 mM) induced a 22% reduction of this lipid. Decreases of phosphatidylethanolamine plasmalogen (8.5%), phosphatidylinositol (16%) and phosphatidylserine (24%) were also seen after intermittent exposure. After binge administration, the concentration of total phospholipids was reduced by 17%, whereas continuous exposure produced a 19% increase. Both intermittent and continuous exposure induced a reduction in the total protein content. No changes in phosphatidic acid, sphingomyelin, phosphatidylcholine plasmalogen or phosphatidylethanolamine (diacyl form) were detected with either treatment. The importance of this study is that ethanol, irrespective of amount, can elicit different effects depending on the pattern of administration.
Alcohol Alcohol Suppl 1991
PMID:Continuous and intermittent exposure to ethanol: effect on NG 108-15 cell membrane phospholipids. 184 41

Long-term ethanol exposure is known to inhibit bradykinin-stimulated phosphoinositide hydrolysis in cultures of neuroblastoma x glioma 108-15 cells. In the present study, [3H]bradykinin binding, GTP-binding protein function, and phospholipase C activity were assayed in cells grown for 4 days in 100 mM ethanol with the aim of elucidating the molecular target of ethanol on signal transduction coupled to inositol trisphosphate and diacylglycerol formation. Ethanol exposure reduced guanosine 5'-O-(3-thiotriphosphate) [GTP(S)]- and, to a lesser extent, NaF/AlCl3-stimulated phosphoinositide hydrolysis, whereas it had no effect on the enzymatic activity of a phosphatidylinositol 4,5-bisphosphate-specific phospholipase C. [3H]Bradykinin binding in the absence of GTP(S) was not influenced by ethanol exposure. However, the reduction in [3H]bradykinin binding seen in control cells after addition of GTP analogue was inhibited in cells grown in ethanol-containing medium. The results indicate that long-term ethanol exposure exerts its effects on receptor-stimulated phosphoinositide hydrolysis primarily at the level of the GTP-binding protein.
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PMID:G proteins coupled to phospholipase C: molecular targets of long-term ethanol exposure. 185 Dec 10

Hyperthermia increases the cytotoxicity of the nitrosourea BCNU (carmustine). Glucose given before treatment may further increase the value of thermochemotherapy, presumably by lowering tumour pH through blood flow reduction. The water-soluble ACNU (nimustine) is an alternative to other nitrosoureas in the treatment of gliomas. The drug is soluble without use of ethanol, and the eye complications when given intra-arterially are reduced compared with similar use of BCNU. The influence of simultaneous hyperthermia on treatment with ACNU, and the value of glucose administered before thermochemotherapy therefore were investigated in the malignant rat glioma BT4An. BD IX rats with subcutaneous BT4An tumours on the hind leg were treated with ACNU (i.p.), or ACNU and locally applied waterbath hyperthermia (44 degrees C for 45 min), with or without previous glucose (6 g/kg i.p. 2 hours before treatment). ACNU (10 or 20 mg/kg) alone and ACNU (20 mg/kg) after previous glucose did not influence tumour growth, compared to the controls. Simultaneous ACNU (10 mg/kg) and hyperthermia clearly was more effective than treatment with hyperthermia alone. Glucose load before treatment further enhanced the effect of combined ACNU and hyperthermia. Glucose before treatment did not change local toxicity or weight profiles of treatment with ACNU alone, or simultaneous ACNU and hyperthermia. Glucose load therefore represented a therapeutic gain when administered before thermochemotherapy with ACNU.
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PMID:Thermal enhancement of ACNU and potentiation of thermochemotherapy with ACNU by hypertonic glucose in the BT4An rat glioma. 189 66

The mechanisms underlying neuronal adaptation to ethanol are poorly understood but appear to involve alterations in cellular membrane structure and/or function. Using a two-dimensional gel analysis, we have recently identified Hsc70 as an ethanol-responsive gene (Miles, M.F. (1989) Neurology 39, (Suppl. 1), 425). Hsc70 is a constitutive member of the 70-kDa stress protein family which plays an important role in protein trafficking and coated vesicle processing. Thus, modulation of Hsc70 by ethanol could produce widespread changes in cellular membrane functioning. Here, we report a detailed study on the regulation of Hsc70 by ethanol in NG108-15 neuroblastoma x glioma cells. Northern and Western blot analyses showed that ethanol concentrations observed in actively drinking alcoholics caused an induction of Hsc70 mRNA and protein. Increases in Hsc70 mRNA were seen as early as 4 h after exposure to ethanol. In comparison with ethanol, propanol and butanol caused proportionally greater increases in Hsc70 mRNA. This is consistent with known anesthetic and intoxicating potencies of these aliphatic alcohols and suggested that lipophilicity, rather than an osmotic effect, was critical for ethanol induction of Hsc70. Induction of Hsc70 mRNA by ethanol resulted, at least in part, from increased Hsc70 gene transcription as determined by nuclear runoff studies. Stable transfection analysis revealed an ethanol-responsive cis-acting element in the proximal 2500 base pairs of the Hsc70 promoter. Regulation of Hsc70 by 50-200 mM ethanol appeared to be a specific change in expression of an ethanol-responsive gene rather than a typical stress protein response since no induction of the highly inducible stress protein, Hsp70, was seen at these ethanol concentrations. These results suggest that ethanol-induced changes in Hsc70 transcription may be important for neuronal adaptation to ethanol and the development of tolerance and dependence in alcoholics.
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PMID:Mechanisms of neuronal adaptation to ethanol. Ethanol induces Hsc70 gene transcription in NG108-15 neuroblastoma x glioma cells. 198 92


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