title: Porphyromonas gingivalis-derived lipopolysaccharide-mediated activation of MAPK signaling regulates inflammatory response and differentiation in human periodontal ligament fibroblasts.
abstract: Porphyromonas gingivalis (P.g.), which is a potential pathogen for periodontal diseases, contains lipopolysaccharide (LPS), and this endotoxin stimulates a variety of cellular responses. At present, P.g.-derived LPS-induced cellular responses in human periodontal ligament fibroblasts (PDLFs) are not well characterized. Here, we demonstrate that P.g-derived LPS regulates inflammatory responses, apoptosis and differentiation in PDLFs. Interleukin-6 (IL-6) and -8 (IL-8) were effectively upregulated by treatment of P.g.-derived LPS, and we confirmed apoptosis markers including elevated cytochrome c levels, active caspase-3 and morphological change in the presence of P.g.-derived LPS. Moreover, when PDLFs were cultured with differentiation media, P.g.-derived LPS reduced the expression of differentiation marker genes, as well as reducing alkaline phosphatase (ALP) activity and mineralization. P.g.-derived LPS-mediated these cellular responses were effectively abolished by treatment of mitogen-activated protein kinase (MAPK) inhibitors. Taken together, our results suggest that P.g.-derived LPS regulates several cellular responses via activation of MAPK signaling pathways in PDLFs.
authors.affiliation: Department of Life Science, Dongguk University-Seoul, Seoul, 100-715, Republic of Korea.
authors.forename: Taegun
authors.initials: T
authors.lastname: Seo
authors.forename: Seho
authors.initials: S
authors.lastname: Cha
authors.forename: Tae-Il
authors.initials: TI
authors.lastname: Kim
authors.forename: Jeong-Soon
authors.initials: JS
authors.lastname: Lee
authors.forename: Kyung Mi
authors.initials: KM
authors.lastname: Woo
mesh_terms: D002454:Cell Differentiation; D002460:Cell Line; D005347:Fibroblasts / Q000166:cytology* / Q000201:enzymology / Q000276:immunology / Q000821:virology; D006801:Humans; D008070:Lipopolysaccharides / Q000276:immunology*; D020935:MAP Kinase Signaling System; D010510:Periodontal Diseases / Q000201:enzymology / Q000276:immunology* / Q000382:microbiology / Q000503:physiopathology; D010513:Periodontal Ligament / Q000166:cytology / Q000201:enzymology / Q000276:immunology* / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000276:immunology* / Q000502:physiology
chemical_list: D008070:Lipopolysaccharides