 |
 |

Evidence for a Cyclic Guanosine Monophosphate—Dependent, Carbon Monoxide—Mediated, Signaling System in the Regulation of TNF- Production by Human Pulmonary Macrophages
Javier Arias-Díaz, MD, PhD;
Elena Vara, PhD;
Cruz Garcia, PhD;
Natividad Villa;
Jose L. Balibrea, MD, PhD
Arch Surg. 1995;130(12):1287-1293.
Abstract
 |  |
Background and Objectives The second messenger cyclic guanosine 3',5'-monophosphate (cGMP) seems to be implicated in the release of tumor necrosis factor (TNF- ) 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- ). In addition, the source and the relative contribution of this molecule to the LPS-induced increase in cell cGMP content and TNF- release were explored.
Design Interstitial 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- , CO (250 and 500 µmol/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- , CO, and NO release to the medium were determined.
Results In the presence of LPS, TNF- 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/µg protein; n=11; P<.01) and cell cGMP content (0.273±0.021 vs 0.138±0.019 pmol/µg protein; n=10; P<.01) was observed. These changes were more pronounced in the presence of LPS+IFN- . Release of TNF- also was induced by both sodium nitroprusside and 8-Br-cGMP. In contrast, methylene blue, a guanylate cyclase inhibitor, inhibited LPS-, LPS+IFN- –, and sodium nitroprusside–induced TNF- production and cGMP increase; hemoglobin, which traps CO, had a similar effect.
Conclusion Intracellular cGMP increase, secondary to an endogenous production of CO, participates in the release of TNF- by activated human pulmonary macrophages.
(Arch Surg. 1995;130:1287-1293)
Author Affiliations
From the Departments of Biochemistry (Facultad de Medicina) (Drs Vara and Garcia and Ms Villa) and Surgery (Hospital San Carlos) (Drs Arias-Díaz and Balibrea), Universidad Complutense, Madrid, Spain.
CiteULike Connotea Del.icio.us Digg Reddit Technorati Twitter
What's this?
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES
Surfactant strengthens the inhibitory effect of C-reactive protein on human lung macrophage cytokine release
Casals et al.
Am. J. Physiol. Lung Cell. Mol. Physiol. 2003;284:L466-L472.
ABSTRACT
| FULL TEXT
cGMP-Mediated Inhibition of TNF-{alpha} Production by the Atrial Natriuretic Peptide in Murine Macrophages
Kiemer et al.
J. Immunol. 2000;165:175-181.
ABSTRACT
| FULL TEXT
Carbon Monoxide Contributes to the Cytokine-Induced Inhibition of Surfactant Synthesis by Human Type II Pneumocytes
Arias-Diaz et al.
Arch Surg 1997;132:1352-1361.
ABSTRACT
|