Porphyromonas gingivalis Lipopolysaccharide Induces a Pro-inflammatory Human Gingival Fibroblast Phenotype.
Human gingival fibroblasts (HGFs) are the major constituents of the gingival tissues responsible for the synthesis and degradation of the connective tissue while actively participating in immune reactions and inflammation. The aim of this study was to test the impact of lipopolysaccharide (LPS) from Porphyromonas gingivalis (P. gingivalis) on human gingival fibroblasts. Human gingival fibroblasts were treated with different P. gingivalis LPS concentrations. Cell survival rate was evaluated with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) after 24 h. Cell proliferation was determined by counting cells on days 3 and 12. Expression of matrix metalloproteinases (MMPs), tissue inhibitors of MMPs (TIMPs), and pro-inflammatory cytokine transcripts in HGFs was determined by quantitative PCR (Q-PCR) analysis on days 3 and 8. P. gingivalis LPS decreased cell proliferation on day 3 (p < 0.05) compared to the control group without significantly impacting the cell survival (p > 0.05).The experiments showed that P. gingivalis LPS dose-dependently and differentially modulated the expression of MMP-1, 2, and 3 and TIMP-1 and 2 on days 3 and 8. TIMP-1 expression was significantly induced in P. gingivalis LPS-treated cells while TIMP-2 was increased in response to 10 and 30 ng/ml of LPS on day 3. P. gingivalis LPS induced up-regulation of MMP-1/TIMP-1 ratio on day 3 and increased MMP-2/TIMP-2 ratio on day 8 dose-dependently. Expression of interleukin (IL)-6 and IL-8 was stimulated at higher concentrations (1000 and 3000 ng/ml) of LPS. These findings demonstrate that P. gingivalis LPS suppresses cell proliferation and leads to increased pro-inflammatory changes in HGFs, suggesting that P. gingivalis LPS-induced modification of phenotypic and inflammatory characteristics in HGF could potentially be a pathogenic mechanism underlying the tissue destruction.
Research Center of Faculty of Dentistry, Selcuk University, Konya, Turkey. buketbozkurt@yahoo.com.
S Buket
SB
Bozkurt
Faculty of Dentistry, Department of Periodontology, Selcuk University, Konya, Turkey.
Sema S
SS
Hakki
Faculty of Agriculture, Department of Soil Science & Plant Nutrition, Selcuk University, Konya, Turkey.
Erdogan E
EE
Hakki
Faculty of Science, Department of Biology, Selcuk University, Konya, Turkey.
Yusuf
Y
Durak
Department of Periodontology, The Forsyth Institute, Boston, MA, USA.
Alpdogan
A
Kantarci
D049109:Cell Proliferation; D002470:Cell Survival; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000382:microbiology / Q000473:pathology*; D005881:Gingiva / Q000382:microbiology / Q000473:pathology*; D006801:Humans; D007249:Inflammation / Q000139:chemically induced / Q000473:pathology*; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D020782:Matrix Metalloproteinases / Q000378:metabolism; D016966:Porphyromonas gingivalis / Q000737:chemistry; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism
C508606:CXCL8 protein, human; C508600:IL6 protein, human; D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; C560822:TIMP1 protein, human; C560823:TIMP2 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D020782:Matrix Metalloproteinases
Porphyromonas gingivalis; cytokine; fibroblast; lipopolysaccharide