Protein kinase C-alpha mediates cigarette smoke extract- and complement factor 5a-stimulated interleukin-8 release in human bronchial epithelial cells
| Autor: | Todd A. Wyatt, Anthony A. Floreani, Sam D. Sanderson, Ravindra Kashyap, Arthur J. Heires |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Protein Kinase C-alpha
chemistry.chemical_element Complement C5a Bronchi Complement factor I Calcium In Vitro Techniques General Biochemistry Genetics and Molecular Biology Calcium in biology Proinflammatory cytokine chemistry.chemical_compound Smoke parasitic diseases Medicine Humans Interleukin 8 Protein kinase C Protein Kinase C business.industry Interleukin-8 Smoking Epithelial Cells General Medicine Molecular biology Isoenzymes Calphostin C chemistry Biochemistry business |
| Zdroj: | Journal of investigative medicine : the official publication of the American Federation for Clinical Research. 50(1) |
| ISSN: | 1081-5589 |
| Popis: | Background Cigarette smoke extract (CSE) activates protein kinase C (PKC) and augments complement factor 5a (C5a)-stimulated release of the proinflammatory cytokine IL-8 in human bronchial epithelial cells (HBEC). We hypothesized that PKC activation by alternative PKC activators will also mediate C5a-stimulated IL-8 release in HBEC. Methods HBEC were treated with phorbol myristate acetate (100 ng/mL), calcium ionophore A23187 (2 nM), or 10 nM cholesterol-3-sulfate in the presence or absence of C5a. Interleukin-8 (IL-8) release was measured by enzyme-linked immunoadsorbent assay. Results IL-8 release by PKC activators alone was significantly higher than in unstimulated cells and was further augmented in the presence of C5a. Preincubation with the PKC inhibitor calphostin C (1 μM) significantly suppressed IL-8 release in HBEC treated with CSE and C5a. Preincubation with 10 μM TMB-8 (an intracellular calcium sequester) also significantly suppressed IL-8 release in CSE- and C5a-treated HBEC, suggesting that intracellular calcium is required for CSE- and C5a-mediated IL-8 release. When HBEC were preincubated with 30 nM of the PKCβ-specific inhibitor LY363196, CSE- and C5a-mediated IL-8 release was not inhibited. However, with higher concentrations of LY363196 (>600 nM), which exceeds the IC50 for PKCβ greater than 100 fold, CSE- and C5a-mediated IL-8 release was significantly suppressed. Preincubation of HBEC with 100 nM of Gö 6976, a specific PKCα inhibitor, significantly inhibited CSE- and C5a-mediated stimulation of IL-8 release. Conclusions Collectively, these data suggest that PKC activators in addition to CSE augment C5a-stimulated IL-8 release from HBEC and that CSE and C5a stimulate IL-8 release in HBEC by activating the calcium-dependent PKCα isoform. |
| Databáze: | OpenAIRE |
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