Potassium regulates IL-1 beta processing via calcium-independent phospholipase A2
| Autor: | Susanne Strauch, Iwan Walev, Sucharit Bhakdi, Angela Valeva, Jochen Klein, Matthias Husmann, Oksana Weichel, Heiner Wirtz |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Intracellular Fluid
Potassium Immunology chemistry.chemical_element Naphthalenes Cleavage (embryo) Monocytes Phospholipases A Phospholipase A2 Calcium-Independent Phospholipase A2 Immunology and Allergy Humans Cells Cultured chemistry.chemical_classification Calcium metabolism biology Tumor Necrosis Factor-alpha Caspase 1 Biological Transport Caspase Inhibitors Cell biology Enzyme Activation Phospholipases A2 Enzyme chemistry Pyrones biology.protein Calcium Efflux Bromoenol lactone Protein Processing Post-Translational Immunosuppressive Agents Interleukin-1 |
| Zdroj: | Journal of immunology (Baltimore, Md. : 1950). 164(10) |
| ISSN: | 0022-1767 |
| Popis: | We report that potassium leakage from cells leads to activation of the Ca2+-independent phospholipase A2 (iPLA2), and the latter plays a pivotal role in regulating the cleavage of pro-IL-1β by the IL-converting enzyme caspase-1 in human monocytes. K+ efflux led to increases of cellular levels of glycerophosphocholine, an unambiguous indicator of phospholipase A2 activation. Both maturation of IL-1β and formation of glycerophosphocholine were blocked by bromoenol lactone, the specific iPLA2 inhibitor. Bromoenol lactone-dependent inhibition of IL-1β processing was not due to perturbation of the export machinery for pro-IL-1β and IL-1β or to caspase-1 suppression. Conspicuously, activation of Ca2+-dependent phospholipase A2 did not support but rather suppressed IL-1β processing. Thus, our findings reveal a specific role for iPLA2 activation in the sequence of events underlying IL-1β maturation. |
| Databáze: | OpenAIRE |
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