Barrier protective effects of rutin in LPS-induced inflammation in vitro and in vivo.

Rutin, an active flavonoid compound, is well known to possess potent antiplatelet, antiviral and antihypertensive properties. In this study, we first investigated the possible barrier protective effects of rutin against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) induced by lipopolysaccharide (LPS) and the associated signaling pathways. The barrier protective activities of rutin were determined by measuring permeability, monocytes adhesion and migration, and activation of pro-inflammatory proteins in LPS-activated HUVECs. We found that rutin inhibited LPS-induced barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of monocytes to human endothelial cells. Rutin also suppressed acetic acid induced-hyperpermeability and carboxymethylcellulose-induced leukocytes migration in vivo. Further studies revealed that rutin suppressed the production of tumor necrosis factor-α (TNF-α) and activation of nuclear factor-κB (NF-κB) by LPS. Collectively, these results suggest that rutin protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases.