Role of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 6 in activation of inflammation in human umbilical vein endothelial cells stimulated by Porphyromonas gingivalis- an in vitro study

Xinzhe Lou; Jianru Liu; Xiangying Ouyang; Wenyi Liu; Ying Xie; Jinsheng Zhong; Peiying Lv; Shengnan Zhang

doi:10.1016/j.jds.2022.09.009

Role of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 6 in activation of inflammation in human umbilical vein endothelial cells stimulated by Porphyromonas gingivalis- an in vitro study

J Dent Sci. 2023 Apr;18(2):510-516. doi: 10.1016/j.jds.2022.09.009. Epub 2022 Sep 27.

Authors

Xinzhe Lou¹, Jianru Liu¹, Xiangying Ouyang¹, Wenyi Liu¹, Ying Xie¹, Jinsheng Zhong¹, Peiying Lv¹, Shengnan Zhang¹

Affiliation

¹ Department of Periodontology, Peking University School and Hospital of Stomatology, National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing, China.

Abstract

Background/purpose: Porphyromonas gingivalis (P. gingivalis) could induce the activation of vascular endothelial cells and promote the formation of atherosclerosis. Nucleotide-binding oligomerization domain-like receptor family pyrin domain containing (NLRP) 6 could recognize P. gingivalis, but its role in atherosclerosis was unknown. The purpose of this study is to investigate the role of NLRP6 in the activation of inflammation in human umbilical vein endothelial cells (HUVECs) stimulated by P. gingivalis.

Materials and methods: The expression level of NLRP6 in HUVECs with or without P. gingivalis-challenge was observed. Down-regulating the expression of NLRP6 in HUVECs, the expression levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein (MCP)-1 were detected. Then, the HUVECs with NLRP6-overexpressed were stimulated by P. gingivalis, the levels of inflammatory cytokines above were examined and compared with those in HUVECs triggered by P. gingivalis only. To evaluate the effect of NLRP6 on bacterial immune escape, the NLRP6 was overexpressed, and the colonies of P. gingivalis that survived in HUVECs were calculated.

Results: NLRP6 was expressed in HUVECs and decreased after P. gingivalis stimulation. Downregulation of NLRP6 decreased the expression levels of IL-1β, IL-6, IL-8, TNF-α and MCP-1 in HUVECs. Those cytokines above in NLRP6-overexpressed HUVECs with P. gingivalis-stimulation significantly increased than in the cells with P. gingivalis-stimulation only. Furthermore, over-expression of NLRP6 decreased the colonies of P. gingivalis survival in HUVECs.

Conclusion: NLRP6 regulated the activation of inflammation in HUVECs triggered by P. gingivalis and played an important role in P. gingivalis survival in endothelial cells.

Keywords: Atherosclerosis; Human umbilical vein endothelial cells; NLRP6; Porphyromonas gingivalis.