• Arch Surg Chicago · Dec 1995

    Evidence for a cyclic guanosine monophosphate-dependent, carbon monoxide-mediated, signaling system in the regulation of TNF-alpha production by human pulmonary macrophages.

    • J Arias-Díaz, E Vara, C García, N Villa, and J L Balibrea.
    • Department of Biochemistry (Facultad de Medicina), Universidad Complutense, Madrid, Spain.
    • Arch Surg Chicago. 1995 Dec 1; 130 (12): 1287-93.

    Background And ObjectivesThe second messenger cyclic guanosine 3',5'-monophosphate (cGMP) seems to be implicated in the release of tumor necrosis factor alpha (TNF-alpha) by activated macrophages. There is controversy regarding the potential of human macrophages to produce nitric oxide (NO). Since guanylate cyclase can be activated also by carbon monoxide (CO) and this gas may be formed endogenously, we examined the ability of human pulmonary macrophages to produce CO in the presence of lipopolysaccharide (LPS) or LPS+interferon gamma (IFN-gamma). In addition, the source and the relative contribution of this molecule to the LPS-induced increase in cell cGMP content and TNF-alpha release were explored.DesignInterstitial macrophages were obtained from multiple organ donor lungs by enzymatic digestion. After 24-hour preculture, purified macrophages were cultured for 24 hours in the presence or absence of LPS, LPS+IFN-gamma, CO (250 and 500 mumol/L), sodium nitroprusside, 8-Br-cGMP, hemoglobin, methylene blue, zinc-protoporphyrin IX, hemin, S-adenosylmethionine, deferoxamine mesylate, or combinations. The cGMP content of the cells and TNF-alpha, CO, and NO release to the medium were determined.ResultsIn the presence of LPS, TNF-alpha production was not accompanied by any detectable increase in the NO release to the medium. However, an increase in medium CO concentration (mean +/- SEM) (5.81 +/- 0.20 vs 3.74 +/- 0.08 pmol/microgram protein; n = 11; P < .01) and cell cGMP content (0.273 +/- 0.021 vs 0.138 +/- 0.019 pmol/microgram protein; n = 10; P < .01) was observed. These changes were more pronounced in the presence of LPS+IFN-gamma. Release of TNF-alpha also was induced by both sodium nitroprusside and 8-Br-cGMP. In contrast, methylene blue, a guanylate cyclase inhibitor, inhibited LPS-, LPS+IFN-gamma-, and sodium nitroprusside-induced TNF-alpha production and cGMP increase; hemoglobin, which traps CO, had a similar effect.ConclusionIntracellular cGMP increase, secondary to an endogenous production of CO, participates in the release of TNF-alpha by activated human pulmonary macrophages.

      Pubmed     Full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…