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PubMed · 2425847

Glucocorticoids decrease the synthesis of type I procollagen mRNAs.

D Cockayne·K M Sterling·S Shull·K P Mintz·S Illeyne·K R Cutroneo
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Abstract

Glucocorticoids selectively decrease procollagen synthesis in animal and human skin fibroblasts. beta-Actin content and beta-actin mRNA are not affected by glucocorticoid treatment of chick skin fibroblasts. The inhibitory effect of glucocorticoids on procollagen synthesis is associated with a decrease in total cellular type I procollagen mRNAs in chick skin fibroblasts. These effects of dexamethasone are receptor mediated as determined by pretreatment with the glucocorticoid antagonists progesterone and RU-486 and with the agonist beta-dihydrocortisol. Dexamethasone has a small but significant inhibitory effect on cell growth of chick skin fibroblasts. The ability of this corticosteroid to decrease the steady-state levels of type I procollagen mRNAs in nuclei, cytoplasm, and polysomes varies. The largest decrease of type I procollagen mRNAs is observed in the nuclear and cytoplasmic subcellular fractions 24 h after dexamethasone treatment. Type I procollagen hnRNAs are also decreased as determined by Northern blot analysis of total nuclear RNA. The synthesis of total cellular type I procollagen mRNAs is reversibly decreased by dexamethasone treatment. In addition the synthesis of total nuclear type I procollagen mRNA sequences is decreased at 2, 4, and 24 h following the addition of radioactive nucleoside and dexamethasone to cell cultures. Although the synthesis of pro alpha 1(I) and pro alpha 2(I) mRNAs is decreased in dexamethasone-treated chick skin fibroblasts, the degradation of the total cellular procollagen mRNAs is not altered while the degradation of total cellular RNA is stabilized. These data indicate that the dexamethasone-mediated decrease of procollagen synthesis in embryonic chick skin fibroblasts results from the regulation of procollagen gene expression.

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ActinsAnimalsChick EmbryoCollagenDexamethasoneFibroblastsGlucocorticoidsKineticsNucleic Acid HybridizationProcollagenProlineRNARNA, Heterogeneous NuclearRNA, MessengerSkinTranscription, GeneticJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D Cockayne, K M Sterling, S Shull, K P Mintz, S Illeyne, K R Cutroneo. 1986-06-03. Glucocorticoids decrease the synthesis of type I procollagen mRNAs.. https://doi.org/10.1021/bi00359a018

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