Research Article

Chlorogenic Acid as a Positive Regulator in LPS-PG-Induced Inflammation via TLR4/MyD88-Mediated NF-κB and PI3K/MAPK Signaling Cascades in Human Gingival Fibroblasts

Figure 4

Inhibited iNOS and COX-2 expressions by selective inhibitor treatment in LPS-PG-stimulated HGF-1 cells. Cells were treated with the indicated concentrations LPS-PG, CGA, MG-132, LY294002, and U0126 for 18 h at 37°C in a humidified atmosphere containing 5% CO2 in order to confirm the anti-inflammatory mechanism of CGA in HGF-1 cells. The relative inhibition of iNOS and COX-2 was quantified by densitometry, and actin was used as an internal control. Data represent the of triplicate experiments. # vs. NC group; and vs. LPS-PG group. Negative control (NC) group refers that CGA, LPS-PG, and selective inhibitors were not treated. LPS-PG: lipopolysaccharide from P. gingivalis; CGA: chlorogenic acid; iNOS: inducible nitric oxide synthase; COX-2: cyclooxygenase-2; HGF: human gingival fibroblast.