Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04141 (granulocyte-macrophage colony-stimulating factor)
 6,790 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycerol-3-phosphocholine; PAF) enhances the release of newly synthesized PAF as measured by [3H]acetate incorporation into PAF in human neutrophils. The response was dose-dependent, rapid, transient, and inhibitable by the PAF antagonist BN-52021. The non-metabolizable bioactive PAF analogue (C-PAF) but not lyso-PAF enhances the release of newly synthesized PAF. Newly synthesized PAF was also released after stimulation of these cells with fMet-Leu-Phe. The human granulocyte-macrophage colony-stimulating factor potentiates the stimulated release of PAF. The intracellular calcium chelator BAPTA inhibits the rise of [Ca2+]i and the release of PAF but not the Na+/H+ antiport activity. PAF release, but not the rise in the intracellular concentration of free calcium, was inhibited in pertussis toxin-treated neutrophils stimulated with PAF. The release of PAF in pertussis toxin-treated cells was also inhibited in cells stimulated with fMet-Leu-Phe or opsonized zymosan. These results suggest that functional pertussis toxin-sensitive guanine nucleotide regulatory protein and/or one or more of the changes produced by phospholipase C activation are necessary for PAF release produced by physiological stimuli. It appears that PAF release requires a coordinated action of receptor-coupled G-proteins, calcium, and other parameters.
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PMID:Calcium is necessary but not sufficient for the platelet-activating factor release in human neutrophils stimulated by physiological stimuli. Role of G-proteins. 251 17

We have prepared a new formulation for mucosal delivery of GM-CSF or PEGylated GM-CSF based on a chitosan carrier plus added glycerol to control the rate of release of the protein. Thin dry films comprised of various weight ratios of chitosan to glycerol and containing either granulocyte-macrophage colony-stimulating factor (GM-CSF) or PEGylated GM-CSF, PEG-(GM-CSF), were prepared. The amount of GM-CSF or PEG-(GM-CSF) released from the chitosan/glycerol films was determined using size exclusion high performance liquid chromatography (HPLC-SEC). The amount of PEG-(GM-CSF) released from the films decreased with an increase in the amount of glycerol present in the film. In parallel with this, films with higher glycerol content exhibited a lower degree of equilibrium swelling when immersed in release media. pH measurements of the release media and analysis of the dried films by Fourier-transform infrared spectroscopy (FTIR) suggested that the amount of residual acetic acid in the dry films decreased as the glycerol content increased. This indicates that glycerol may act by displacing and releasing bound acetic acid from the chitosan molecules, resulting in chitosan--glycerol hydrogen bond formation as the film dries. Further, it was found that the release rate and the amount of PEG-(GM-CSF) released decreased with increasing molecular weight of the conjugated PEG. This effect was not observed with films containing physical mixtures of PEG and GM-CSF. The decrease in the fraction of PEG-(GM-CSF) released with increasing PEG molecular weight is believed to be due to the increased steric hindrance of the PEGylated protein molecule during its diffusion out of the swollen chitosan/glycerol film.
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PMID:Release of PEGylated granulocyte-macrophage colony-stimulating factor from chitosan/glycerol films. 1138 83