摘要
This study investigates the signaling pathway involved in inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) release caused by Staphylococcus aureus lipoteichoic acid (LTA) in RAW 264.7 macrophages. A phosphatidylcholine-phospholipase C (PC-PLC) inhibitor (D-609) and a phosphatidylinositol-phospholipase C (PI-PLC) inhibitor (U-73122) attenuated LTA-induced iNOS expression and NO release. Two PKC inhibitors (Go 6976 and Ro 31-8220), an NF-κB inhibitor (pyrrolidine dithiocarbamate; PDTC), and long-term (24 h) 12-phorbol-13-myristate acetate (PMA) treatment each also inhibited LTA-induced iNOS expression and NO release. Treatment of cells with LTA caused an increase in PKC activity; this stimulatory effect was inhibited by D-609, U-73122, or Ro 31-8220. Stimulation of cells with LTA caused IκB-α phosphorylation and IκB-α degradation in the cytosol, and translocation of p65 and p50 NF-κB from the cytosol to the nucleus. Treatment of cells with LTA caused NF-κB activation by detecting the formation of NF-κB-specific DNA-protein complexes in the nucleus; this effect was inhibited by Go 6976, Ro 31-8220, long-term PMA treatment, PDTC, L-1-tosylamido-2-phenylethyl chloromethyl ketone (TPCK), and calpain inhibitor I. These results suggest that LTA might activate PC-PLC and PI-PLC to induce PKC activation, which in turn initiates NF-κB activation, and finally induces iNOS expression and NO release in RAW 264.7 macrophages.
原文 | 英語 |
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頁(從 - 到) | 136-145 |
頁數 | 10 |
期刊 | Journal of Biomedical Science |
卷 | 10 |
發行號 | 1 |
DOIs | |
出版狀態 | 已發佈 - 2003 |
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)