Abstract
The ability to produce nitric oxide (NO) of human monocytes macrophages is object of debate. While studying the regulation of tumor necrosis factor (TNF) synthesis induced by endotoxin (LPS) in a human cell line of monocyte origin (THP-1) and in human peripheral blood mononuclear cells (PBMC) we found an indirect evidence of such production. We showed that L-N-monomethyl-arginine (L-NMMA), an inhibitor of NO synthase, and hemoglobin, a chelator of NO, are able to significantly reduce TNF synthesis, indicating that NO production is induced by LPS and contributes to the induction of TNF. Since NO is a known cytostatic agent, we also studied the cytostatic effect of LPS, and demonstrated that it is reverted by L-NMMA. Although we were unable to show any nitrites/nitrates accumulation in the culture media, taken together our data give an indirect evidence of a physiologically relevant LPS-induced NO production in human monocytes-macrophages.
| Original language | English |
|---|---|
| Pages (from-to) | 45-48 |
| Number of pages | 4 |
| Journal | European Cytokine Network |
| Volume | 6 |
| Issue number | 1 |
| Publication status | Published - 1995 |
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Keywords
- Human monocytes/macrophages
- Nitric oxide
- Tumor necrosis factor
ASJC Scopus subject areas
- Cell Biology
- Immunology
Cite this
Endogenous nitric oxide production by human monocytic cells regulates LPS-induced TNF production. / Zinetti, M.; Fantuzzi, G.; Delgado, R.; Di Santo, E.; Ghezzi, P.; Fratelli, M.
In: European Cytokine Network, Vol. 6, No. 1, 1995, p. 45-48.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Endogenous nitric oxide production by human monocytic cells regulates LPS-induced TNF production
AU - Zinetti, M.
AU - Fantuzzi, G.
AU - Delgado, R.
AU - Di Santo, E.
AU - Ghezzi, P.
AU - Fratelli, M.
PY - 1995
Y1 - 1995
N2 - The ability to produce nitric oxide (NO) of human monocytes macrophages is object of debate. While studying the regulation of tumor necrosis factor (TNF) synthesis induced by endotoxin (LPS) in a human cell line of monocyte origin (THP-1) and in human peripheral blood mononuclear cells (PBMC) we found an indirect evidence of such production. We showed that L-N-monomethyl-arginine (L-NMMA), an inhibitor of NO synthase, and hemoglobin, a chelator of NO, are able to significantly reduce TNF synthesis, indicating that NO production is induced by LPS and contributes to the induction of TNF. Since NO is a known cytostatic agent, we also studied the cytostatic effect of LPS, and demonstrated that it is reverted by L-NMMA. Although we were unable to show any nitrites/nitrates accumulation in the culture media, taken together our data give an indirect evidence of a physiologically relevant LPS-induced NO production in human monocytes-macrophages.
AB - The ability to produce nitric oxide (NO) of human monocytes macrophages is object of debate. While studying the regulation of tumor necrosis factor (TNF) synthesis induced by endotoxin (LPS) in a human cell line of monocyte origin (THP-1) and in human peripheral blood mononuclear cells (PBMC) we found an indirect evidence of such production. We showed that L-N-monomethyl-arginine (L-NMMA), an inhibitor of NO synthase, and hemoglobin, a chelator of NO, are able to significantly reduce TNF synthesis, indicating that NO production is induced by LPS and contributes to the induction of TNF. Since NO is a known cytostatic agent, we also studied the cytostatic effect of LPS, and demonstrated that it is reverted by L-NMMA. Although we were unable to show any nitrites/nitrates accumulation in the culture media, taken together our data give an indirect evidence of a physiologically relevant LPS-induced NO production in human monocytes-macrophages.
KW - Human monocytes/macrophages
KW - Nitric oxide
KW - Tumor necrosis factor
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M3 - Article
VL - 6
SP - 45
EP - 48
JO - Environmental and Molecular Mutagenesis
JF - Environmental and Molecular Mutagenesis
SN - 0893-6692
IS - 1
ER -