Azithromycin suppresses P. gingivalis LPS-induced pro-inflammatory cytokine and chemokine production by human gingival fibroblasts in vitro

Azithromycin is a macrolide antibiotic that appears to have both antibacterial and anti-inflammatory properties. This study aimed to investigate the effect of azithromycin on the production of pro-inflammatory cytokines and chemokines by human gingival fibroblasts (HGF) in vitro. The effects of azithromycin (0.1 to 10 mu g/mL) on the production of interleukin-6 (IL-6), interleukin-8 (IL-8), monocyte chemoattractant protein 1 (MCP-1), and growth-regulated oncogene (GRO) by human gingival fibroblasts cultured in the presence or absence of Porphyromonas gingivalis lipopolysaccharide (LPS) was studied. Cytokine and chemokine protein levels in the culture supernatant were assessed using a LuminexA (R) multiplex immunoassay. P. gingivalis LPS induced cytokine/chemokine (IL-6, IL-8, MCP-1, and GRO) protein production in HGFs, and this effect was suppressed by azithromycin at all concentrations tested. This study demonstrates that azithromycin suppresses P. gingivalis LPS-induced cytokine/chemokine protein production in HGF, which may explain some of the clinical benefits observed with the adjunctive use of azithromycin in the treatment of periodontitis. The current study examines the anti-inflammatory properties of azithromycin which may make it useful as an adjunct treatment to periodontitis. Specifically, we used azithromycin to modulate the production of pro-inflammatory cytokines by gingival fibroblasts known to be important in periodontal inflammation.