Crocetin Inhibits Lipopolysaccharide-Induced Inflammatory Response in Human Umbilical Vein Endothelial Cells

Crocetin is a readily bioavailable and bioactive compound extracted from Saffron. Previous studies indicated its various biomedical properties including antioxidant and anti-coagulation potencies. However, its effect on inflammation, notably within the cardiovascular system, has not been investigated yet. In the present study, we utilized human umbilical vein endothelial cell (HUVEC) to elucidate the effect of Crocetin on vascular inflammation.

Cell viability and toxicity were evaluated by MTT and Lactate dehydrogenase (LDH) assay, respectively. Pro-inflammatory chemokine Monocyte Chemoattractant Protein-1 (MCP-1) and Interleukin-8 (IL-8) expressions were determined by RT-PCR and ELISA. With fluorescence labeled U937 cells, we examined immune cell adhesion to the inflamed HUVEC in vitro, which was further confirmed by the H&E staining in the murine subcutaneous endothelium in vivo.

Upon Lipopolysaccharide (LPS)-induced inflammatory response in HUVECs, Crocetin ameliorated cell cytotoxicity, suppressed MCP-1 and IL-8 expressions through blocking NF-κB p65 signaling transduction. Moreover, Crocetin inhibited immune cells adhesion and infiltration to inflamed endothelium, which is a key step in inflammatory vascular injury.

These findings suggest that Crocetin, a natural herb extract, is a potent suppressor of vascular endothelial inflammation.