Toll-like receptor 4 regulates the inflammation induced by lipids in smooth muscle cells

doi:10.16150/j.1671-2870.2017.05.010

Abstract

Abstract: Objective: To investigate the mechanism of TLR4 in mediating the oxLDL-induced inflammation in smooth muscle cells (SMCs). Methods: TLR4 knockout mice and wild type C57BL/6 mice were randomly divided into control group (normal diet) and study group (high-fat diet) with 6 mice per group. Progression of atheroma was analyzed after 12 weeks in TLR4 knockout mice and wild type C57BL/6 mice. Primary SMCs of TLR4 knockout mice were cultured in vitro, and SMCs of wild type C57BL/6 were served as controls. SMCs were treated with oxLDL to induce inflammation, then TLR4 antibody was used to block TLR4 activity, and oxLDL-induced inflammation was compared between TLR4 knockout mice and wild type C57BL/6 mice. Results: High-fat diet could promote the expression of inflammatory cytokines in wild type C57BL/6 mice, but in TLR4 knockout mice there was no significant difference between the normal and high-fat diet groups. Moreover, blocking the activity of TLR4 could inhibit the oxLDL-induced inflammation in primary SMCs. Conclusions: TLR4 plays a role in regulating the oxLDL-induced inflammation in SMCs.

Key words: Toll-Like Receptor 4, Smooth Muscle Cells, Lipid, Inflammation, Cytokines

CLC Number:

R543.5

WANG Yanping, CHEN Yuanyuan, WU Liping, CHEN Yafen, YANG Ke, LIU Yan. Toll-like receptor 4 regulates the inflammation induced by lipids in smooth muscle cells[J]. Journal of Diagnostics Concepts & Practice, 2017, 16(05): 504-509.

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