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)

Neuroblastoma x glioma cells NG108-15 were cultured in lipid-free medium supplemented with fatty acids of various chain length and unsaturation. Binding of 3H-labelled [DAla2]-[DLeu5]-enkephalin by membranes of cells grown in saturation fatty acids of different chain length was not significantly different from that of the control On the other hand, a proportional decrease of binding capacity with no change in residual receptor affinity was noticed when cells were cultured in medium containing fatty acids of increasing unsaturation. This decrease was time dependent and reached a maximum at about 48 h. Binding of [3H]dihydromorphine and [3H]naloxone was similarly affected. In contrast, when membranes of cells grown in normal medium were preincubated up to 3 h with unsaturated fatty acid and tested for opioid binding, no significant reduction was observed. Examination of the fatty acid composition of phospholipid from cells grown in linolenate indicated that a significant alteration of the acyl composition has occurred. To evaluate the underlying cause of this type of inhibition, the effect of linolenic acid on cell growth and protein synthesis was examined. When cells were cultured in 100 microM of this fatty acid, both growth and protein synthesis were retarded by 28% and 19%, respectively. Since opiate receptors are proteineous in nature, a reduction of protein synthesis may partially account for the loss of opioid binding activity. On the other hand, an increase of membrane fluidity is known to affect a number of cellular functions, including ligand-receptor recognition. Whether this can offer a satisfactory explanation for our observations remains to be established.
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PMID:Reduction of opioid binding in neuroblastoma x glioma cells grown in medium containing unsaturated fatty acids. 628 29

As a first step in studying the effects of membrane lipid modification on complex cellular functions we have modified the membrane fatty acid composition of the neuroblastoma X glioma hybrid clone, NG108-15. These cultured cells were chosen because they exhibit many complex neuronal functions in vitro. Unsaturated fatty acids (oleate, linoleate, linolenate and arachidonate) were accumulated, metabolized and esterified by the cells. These unsaturated fatty acids stimulated cell growth, whereas saturated fatty acids were toxic to the cells. Changes as large as 40-fold in the ratio of monounsaturated/polyunsaturated fatty acids in the membrane phospholipids were produced by addition of fatty acids directly to serum-containing culture medium. As a result of the exposure of NG108-15 cells to unsaturated fatty acids the amount of phosphatidylethanolamine in the cells was increased by as much as 60%. Polyunsaturated fatty acids also caused a small decrease in the membrane cholesterol/phospholipid molar ratio. These experiments demonstrate that large changes in membrane fatty acid composition can be created in clonal cells capable of differentiated neuronal activities. Additional changes in membrane lipid composition also appear to be induced by these manipulations. The question of the importance of specific membrane lipid composition to neuronal cellular function now can be addressed.
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PMID:Membrane fatty acid modification of the neuroblastoma x glioma hybrid, NG108-15. 721 69