Biomaterial Database

Effect of methylxanthines on binding of the glucocorticoid receptor to DNA-cellulose and nuclei. 1978

M H Cake, and G Litwack

The binding of [3H]dexamethasone-receptor complex from rat liver cytosol to isolated nuclei or DNA-cellulose can be greatly enhanced at low temperature by the presence of theophylline. Aminophylline and caffeine can mimic this effect; however, papaverine and 1-methyl-3-isobutylxanthine, at concentrations inhibitory to phosphodiesterase, are without effect on glucocorticoid receptor binding to DNA. Furthermore, theophylline can be added when adenosine 3':5'-monophosphate-(cAMP) hydrolysis is already complete and still enhance DNA binding. These results imply that this effect of theophylline is independent of its known effect on cAMP levels. Activation by methylxanthines does not alter the sedimentation of the glucocorticoid-receptor complex in sucrose gradients but does alter the pI and in this respect brings about changes resembling those which occur upon activation by heat. Recently we have shown that pyridoxal phosphate inhibits the binding of heat-activated receptor to DNA-cellulose. Similarly, we have shown here that pyridoxal phosphate also inhibits the DNA-cellulose binding of theophylline-treated receptor. The presence of theophylline also enhances the rate of binding of [3H]dexamethasone to the receptor and increases its apparent affininty for the steroid. The data suggest that the effect of theophylline is on some cytosolic component, perhaps the receptor itself. Enhanced DNA binding as a result of exposure to theophylline at low temperature can also be demonstrated using the glucocorticoid receptor of kidney, thymus and Reuber H35 cells.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008297	Male		Males
D011965	Receptors, Glucocorticoid	Cytoplasmic proteins that specifically bind glucocorticoids and mediate their cellular effects. The glucocorticoid receptor-glucocorticoid complex acts in the nucleus to induce transcription of DNA. Glucocorticoids were named for their actions on blood glucose concentration, but they have equally important effects on protein and fat metabolism. Cortisol is the most important example.	Corticoid Type II Receptor,Glucocorticoid Receptors,Glucocorticoids Receptor,Corticoid II Receptor,Corticoid Type II Receptors,Glucocorticoid Receptor,Receptors, Corticoid II,Receptors, Corticoid Type II,Receptors, Glucocorticoids,Corticoid II Receptors,Glucocorticoids Receptors,Receptor, Corticoid II,Receptor, Glucocorticoid,Receptor, Glucocorticoids
D011987	Receptors, Steroid	Proteins found usually in the cytoplasm or nucleus that specifically bind steroid hormones and trigger changes influencing the behavior of cells. The steroid receptor-steroid hormone complex regulates the transcription of specific genes.	Corticosteroid Receptors,Receptors, Corticosteroid,Steroid Receptors,Corticosteroid Receptor,Receptors, Steroids,Steroid Receptor,Receptor, Corticosteroid,Receptor, Steroid,Steroids Receptors
D002110	Caffeine	A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.	1,3,7-Trimethylxanthine,Caffedrine,Coffeinum N,Coffeinum Purrum,Dexitac,Durvitan,No Doz,Percoffedrinol N,Percutaféine,Quick-Pep,Vivarin,Quick Pep,QuickPep
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D003907	Dexamethasone	An anti-inflammatory 9-fluoro-glucocorticoid.	Hexadecadrol,Decaject,Decaject-L.A.,Decameth,Decaspray,Dexasone,Dexpak,Hexadrol,Maxidex,Methylfluorprednisolone,Millicorten,Oradexon,Decaject L.A.
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA