Under abnormal WSS, nuclear factor-κB (NF-κB) in cerebral arterial walls upregulates expression of downstream genes, such as monocyte chemoattractant protein 1 (MCP-1) and vascular cell adhesion molecule 1 (VCAM-1) gene, which lead to macrophage infiltration and endothelial dysfunction. Here, CCL2 is linked to endothelial dysfunction.