title: [Intracellular mechanisms of Porphyromonas gingivalis induced interleukin-8 upregulation in endothelial cells].
abstract: OBJECTIVE
  To find out the mechanisms by which Porphyromonas gingivalis (P. gingivalis) regulates interleukin (IL)-8 expression in endothelial cells.
  
  
  METHODS
  P. gingivalis was applied to infect human umbilical vein endothelial cells (HUVECs), and the expressions of nucleotide binding oligomerization domain (NOD) 1, NOD2 and IL-8 were detected at mRNA and protein levels. Then the NOD1/NOD2 gene was silenced by RNA interference targeting NOD1 or NOD2 mRNA, followed by P. gingivalis treatment in the HUVECs, and the expression levels of NOD1/NOD2 and IL-8 were examined by real-time PCR, Western-blot or ELISA. In order to confirm the relationship between NOD1/NOD2 and IL-8 in the HUVECs, the agonists for NOD1 and NOD2, DAP and MDP were used in this study.
  
  
  RESULTS
  P. gingivalis was activated the expressions of NOD1 and NOD2 in the HUVECs. Meanwhile, IL-8 expression level was also upreguated after P. gingivalis treatment (P<0.01). Knocking down of NOD1 or NOD2, the expression level of NOD1 or NOD2 was decreased, and P. gingivalis-induced IL-8 expression was attenuated in the HUVECs (P<0.01). Compared with normal cells, the NOD1 and NOD2 agonists, DAP and MDP, successfully increased IL-8 expression respectively (P<0.05).
  
  
  CONCLUSIONS
  NOD1 and NOD2 play an important role in the inflammation of HUVECs caused by P. gingivalis in the expression of IL-8.
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Xiang-ying
authors.initials: XY
authors.lastname: Ouyang
authors.affiliation: Department of Periodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Wan
mesh_terms: D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism* / Q000382:microbiology; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism*; D053474:Nod1 Signaling Adaptor Protein / Q000378:metabolism*; D053473:Nod2 Signaling Adaptor Protein / Q000378:metabolism*; D016966:Porphyromonas gingivalis; D034622:RNA Interference; D012333:RNA, Messenger; D015854:Up-Regulation
chemical_list: C508606:CXCL8 protein, human; D016209:Interleukin-8; C119067:NOD1 protein, human; C429018:NOD2 protein, human; D053474:Nod1 Signaling Adaptor Protein; D053473:Nod2 Signaling Adaptor Protein; D012333:RNA, Messenger