Aescin Protection of Human Vascular Endothelial Cells Exposed to Cobalt Chloride Mimicked Hypoxia and Inflammatory Stimuli

Abstract

Human vascular endothelial cells (HUVECs) were exposed to CoCl₂ as an in vitro model of hypoxia. Expression of VCAM-1 (vascular cell adhesion molecule), reduction of PECAM-1 (platelet endothelial cell adhesion molecule) and cytoskeletal changes without alterations in cell viability were observed. HUVECs were also exposed to Escherichia coli lipopolysaccaride (LPS) as an in vitro model of inflammation: significant IL-6 release was measured. Pre-treatment of HUVECs with aescin prevented, in a concentration-dependent fashion (0.1 - 1 μM), the action of CoCl₂ on VCAM-1 and PECAM-1, also preserving endothelial cell morphology. Furthermore, aescin pre-treatment reduced IL-6 release from LPS-activated vascular endothelium.

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