interleukin-8 and citral

Citral is an active compound of lemongrass oil which has been reported to have anti-inflammatory effects. In this study, we investigated the effects of citral on lipopolysaccharide (LPS)-induced inflammatory response in a rat model of peritonitis and human umbilical vein endothelial cells (HUVECs). LPS was intraperitoneally injected into rats to establish a peritonitis model. The HUVECs were treated with citral for 12 h before exposure to LPS. The levels of TNF-α and IL-8 were measured using ELISA. Western blotting was used to detect the expression of VCAM-1, ICAM-1, NF-κB, and PPAR-γ. The results showed that citral had a protective effect against LPS-induced peritonitis. Citral decreased the levels of WBCs and inflammatory cytokines TNF-α and IL-6. Citral also inhibited LPS-induced myeloperoxidase (MPO) activity in the peritoneal tissue. Treatment of HUVECs with citral significantly inhibited TNF-α and IL-8 expression induced by LPS. LPS-induced VCAM-1 and ICAM-1 expression were also suppressed by citral. Meanwhile, we found that citral inhibited LPS-induced NF-κB activation in HUVECs. Furthermore, we found that citral activated PPAR-γ and the anti-inflammatory effects of citral can be reversed by PPAR-γ antagonist GW9662. In conclusion, citral inhibits LPS-induced inflammatory response via activating PPAR-γ which attenuates NF-κB activation and inflammatory mediator production.

Topics: Acyclic Monoterpenes; Anilides; Animals; Anti-Inflammatory Agents; Cell Adhesion; Enzyme Activation; Human Umbilical Vein Endothelial Cells; Humans; Inflammation; Intercellular Adhesion Molecule-1; Interleukin-6; Interleukin-8; Leukocyte Count; Lipopolysaccharides; Monoterpenes; Neutrophils; NF-kappa B; Peritonitis; Peroxidase; Plant Oils; PPAR gamma; Rats; Terpenes; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1