title: Azithromycin reduces tumor necrosis factor-alpha production in lipopolysaccharide-stimulated THP-1 monocytic cells by modification of stress response and p38 MAPK pathway.
abstract: Macrolide antibiotics are known to have a variety of immunomodulatory effects in addition to antimicrobial activity, but the mechanisms of immunomodulation are still unclear. We investigated in vitro the effect of azithromycin on tumor necrosis factor alpha (TNF-alpha) production in lipopolysaccharide (LPS)-stimulated THP-1 cells, a human monocytic cell line, and compared the results with those for other macrolides, minocycline and ofloxacin. In the presence of LPS, treatment with azithromycin (AZM) resulted in a significant decrease in LPS-induced TNF-alpha production compared to that with other antimicrobial agents. the results of phosphorylation of three MAPKs, ERK, JNK and p38, indicated that the phospho-p38 level was reduced by AZM. Ikappab-alpha, an inhibitor of NFkappab, was not disrupted by the antibiotics. LPS-induced TNF-alpha release from THP-1 cells was inhibited in the presence of KNK437, a potent 70-kDa heat shock protein (HSP-70) inhibitor. Interestingly, the induction of HSP-70 by LPS was attenuated with the concurrent addition of AZM in the cells. AZM was found to restrain TNF-alpha production by monocytes at least in part by modifying the HSp-70 and p38 related signaling pathways to LPS stimulation.
authors.affiliation: Division of Hematology and Cardiology, Faculty of Medical Science, Fukui University, Fukui, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Ikegaya
authors.forename: K
authors.initials: K
authors.lastname: Inai
authors.forename: H
authors.initials: H
authors.lastname: Iwasaki
authors.forename: H
authors.initials: H
authors.lastname: Naiki
authors.forename: T
authors.initials: T
authors.lastname: Ueda
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017963:Azithromycin / Q000494:pharmacology*; D015153:Blotting, Western; D002478:Cells, Cultured; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D000072000:NF-KappaB Inhibitor alpha; D015398:Signal Transduction; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D018840:HSP70 Heat-Shock Proteins; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides; C000606204:NFKBIA protein, human; D014409:Tumor Necrosis Factor-alpha; D000072000:NF-KappaB Inhibitor alpha; D017963:Azithromycin; D048051:p38 Mitogen-Activated Protein Kinases