In this study, we report the <i>in vivo</i> biological functionality of these LDLs (both nLDL and sLDL)-based Gd(III)-based contrast agents (GBCAs) by conducting detailed <i>in vivo</i> studies on two types of atherosclerosis murine models, namely, <i>apoE</i> <sup><i>-/-</i></sup> and <i>LDLr</i> <sup><i>-/-</i></sup> . This evidence concerns the gene APOE and atherosclerosis.