Schmid D, Svoboda M, Sorgner A, Moravcevic I, Thalhammer T, Chiba P, Möslinger T. Glibenclamide reduces proinflammatory cytokines in an ex vivo model of human endotoxinaemia under hypoxaemic conditions.
Life Sci 2011;
89:725-34. [PMID:
21925514 DOI:
10.1016/j.lfs.2011.08.017]
[Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 07/31/2011] [Accepted: 08/18/2011] [Indexed: 02/05/2023]
Abstract
AIMS
In vivo application of the K(ATP)-channel blocker glibenclamide can reverse endotoxin-induced hypotension, vascular hyporeactivity and shock in experimental animals. The hypothesis of the present study is, that the drug effects might not only be based on direct inhibition of K(ATP)-channels of vascular smooth muscle cells, but might also reflect reduction of shock-induced excess proinflammatory cytokines and procoagulatory molecules produced in the blood monocytes.
MAIN METHODS
Human whole blood (normoxaemic or hypoxaemic) supplemented ex vivo with 100 ng/ml LPS was used to assess glibenclamide (3-100 μM) effects on IL-1 beta, IL-6, TNF-alpha, tissue factor, and plasminogen-activator-inhibitor-2 (PAI-2). Co-incubations with monocytes and erythrocytes and cytosolic calcium measurements were performed to reveal their purinergic intercellular interaction.
KEY FINDINGS
In heparinized blood, glibenclamide reduced LPS-induced release of IL-1 beta and TNF-alpha, tissue factor and PAI-2 mRNA in a concentration-dependent manner. When samples were subjected to strong hypoxemia using 95% N(2)/5% CO(2), these parameters became even more sensitive to the drug. No drug effect was observable in citrated blood or in isolated monocytes. IL-1 beta mRNA inhibition by glibenclamide appeared to be dependent on P2X7-receptor activation of monocytes by ATP-releasing erythrocytes during hypoxia. Cytosolic calcium values as well as the duration of calcium transients elicited by P2X7-receptor stimulation in isolated monocytes were strongly increased during hypoxia, both of which could be abolished by glibenclamide.
SIGNIFICANCE
We conclude that the anti-inflammatory effect of glibenclamide is mainly based on the reduction of calcium entry by drug-induced depolarization of hypoxic monocytes. Thus, glibenclamide possesses a potentially beneficial shock-specific anti-inflammatory action.
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