These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Induction of cyclooxygenase-2 is responsible for interleukin-1 beta-dependent prostaglandin E2 synthesis by human lung fibroblasts.
    Author: Endo T, Ogushi F, Sone S, Ogura T, Taketani Y, Hayashi Y, Ueda N, Yamamoto S.
    Journal: Am J Respir Cell Mol Biol; 1995 Mar; 12(3):358-65. PubMed ID: 7873203.
    Abstract:
    Because interleukin-1 beta (IL-1 beta) increases the synthesis of prostaglandin E2 (PGE2) in human lung fibroblasts, the effect of IL-1 beta on the expression of two isozymes of cyclooxygenase (cyclooxygenase-1 and -2) in human embryonic lung fibroblasts (IMR-90) was investigated in terms of three parameters (PGE2 release, cyclooxygenase activity, and mRNA). When the cells were incubated with IL-1 beta, both the PGE2 release to the culture medium and the cyclooxygenase activity in the cell lysate increased in a dose- and time-dependent manner, and both were inhibited by NS-398 (a cyclooxygenase-2-specific inhibitor). Dexamethasone and interleukin-4 (IL-4) inhibited the IL-1 beta-induced PGE2 synthesis; the former inhibited the IL-1 beta-induced cyclooxygenase activity whereas the latter failed. As analyzed by Northern blot, cyclooxygenase-1 mRNAs (3.0 Kb and 5.0 Kb) were detected with resting cells and did not increase by the addition of IL-1 beta. In contrast, the cyclooxygenase-2 mRNA (4.4 Kb) was undetectable with resting cells, but was increased dramatically up to 4 to 8 h by the addition of IL-1 beta. Dexamethasone inhibited the IL-1 beta-induced mRNA expression of cyclooxygenase-2 whereas IL-4 failed. These results indicate that IL-1 beta induces cyclooxygenase-2 rather than cyclooxygenase-1 in IMR-90 cells and this induction is responsible for the augmentation of PGE2 production stimulated with IL-1 beta. However, the inhibition of the IL-1 beta-induced PGE2 synthesis by IL-4 was not mediated by the down-regulation of cyclooxygenase-2.
    [Abstract] [Full Text] [Related] [New Search]