Experimental studies manifested that berberine decreased PCSK9 mRNA and protein levels in a time- and dose-dependent manner in HepG2 cells and improved dyslipidemia with lipopolysaccharide-induced inflammation by way of modifying the PCSK9/LDLR signaling pathway in C57BL/6 mice (Cameron et al., 2008; Xiao et al., 2012). This evidence concerns the gene PCSK9 and metabolic syndrome.