TLR4 and atherosclerosis: Feng et al. (2014) demonstrated that miR-21 negatively regulated lipopolysaccharide (LPS)-induced lipid accumulation and inflammatory responses in macrophages via the Toll-like receptor 4 (TLR4)/NF-κB pathway. Overexpression of miR-21 could reverse the pathological processes of atherosclerosis, suggesting a promising therapeutic avenue for the prevention and treatment of atherosclerosis (Feng et al., 2014).