title: Proteolytic activity of Porphyromonas gingivalis attenuates MCP-1 mRNA expression in LPS-stimulated THP-1 cells.
abstract: Bacteria can modulate cytokine production of host cells. In this study, we examined effects of Porphyromonas gingivalis, an important periodontal pathogen, on the cytokine production in lipopolysaccharide (LPS)-stimulated THP-1 macrophagic cells. A wide range of doses of P. gingivalis increased the tumor necrosis factor-α (TNF-α) production. However, monocyte chemoattractant protein-1 (MCP-1) production was substantially suppressed by high doses of P. gingivalis and this effect was demonstrated at the mRNA level. Challenges with a congenic protease mutant strain did not significantly attenuate the MCP-1 mRNA expression and addition of leupeptin, a protease inhibitor, to the cultures largely prevented the inhibition of MCP-1 expression by P. gingivalis. Transwell experiments showed that direct contact of P. gingivalis with THP-1 cells was not required for the MCP-1 inhibition. Furthermore, blockade of internalization of P. gingivalis into THP-1 cells had no effect on the MCP-1 inhibition by P. gingivalis. Finally, degradation of MCP-1 mRNA in LPS-stimulated THP-1 cells was accelerated in the presence of P. gingivalis. These results suggest that the proteolytic activity of P. gingivalis attenuate MCP-1 mRNA expression by promoting the decay of MCP-1 mRNA in LPS-stimulated THP-1 cells.
authors.affiliation: Department of Oral Microbiology, School of Dentistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Eun-Kyoung
authors.initials: EK
authors.lastname: Choi
authors.affiliation: Department of Oral Microbiology, School of Dentistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: Sang-Yong
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Oral Microbiology, School of Dentistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea.
authors.forename: So-Hee
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Physical Therapy, Gwangju Health University, Gwangju 506-701, Republic of Korea.
authors.forename: Yun-Woong
authors.initials: YW
authors.lastname: Paek
authors.affiliation: Department of Oral Microbiology, School of Dentistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Republic of Korea. Electronic address: ickang@jnu.ac.kr.
authors.forename: In-Chol
authors.initials: IC
authors.lastname: Kang
mesh_terms: D002460:Cell Line; D018932:Chemokine CCL2 / Q000096:biosynthesis*; D054884:Host-Pathogen Interactions; D006801:Humans; D057131:Immune Evasion; D008070:Lipopolysaccharides / Q000276:immunology*; D009000:Monocytes / Q000187:drug effects / Q000276:immunology* / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000201:enzymology* / Q000276:immunology*; D059748:Proteolysis; D012333:RNA, Messenger / Q000096:biosynthesis
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; D008070:Lipopolysaccharides; D012333:RNA, Messenger
keywords: Lipopolysaccharide; Monocyte chemoattractant protein-1; Periodontitis; Porphyromonas gingivalis; Protease; THP-1