Cumulative evidence suggests that the upregulation of inflammatory factors such as tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant factor-1 (MCP-1 or CCL2), and subsequent leukocyte diapedesis, contribute to the BRB breakdown in diabetes. Here, ICAM1 is linked to diabetes mellitus.