TLR4 and atherosclerosis: It is widely accepted that atherosclerosis involves chronic inflammatory reaction.8 Toll-like receptor 4 (TLR4), one intensively investigated member of the TLR family, has a critical role in initiating inflammation, and participates in VSMC activation.9, 10 Lipopolysaccharide (LPS) is a TLR4-specific ligand that can trigger TLR4-mediated inflammation.