Involvement of heme oxygenase-1 induction in anti-vascular inflammation effects of Xanthoceras sorbifolia in human umbilical vein endothelial cells

OBJECTIVE: To define the effects of Xanthoceras sorbifolia(EXS) on vascular inflammation and the mechanisms in endothelial cells.METHODS: Vascular protective effects of an ethanol extract of seeds from EXS(1-50 μg/mL) against tumor necrosis factor-α(TNF-α)-induced vascularinflammation were examined in human umbilical vein endothelial cells(HUVECs).RESULTS: EXS significantly decreased TNF-α-induced expression of cell adhesion molecules, such as intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and endothelial cell selectin,in a dose-dependent manner. Pre-treatment with EXS significantly inhibited translocation and transcriptional activity of nuclear factor-κB(NF-κB) increased by TNF-α. EXS also significantly inhibited formation of intracellular reactive oxygen species(ROS). Moreover, the vascular protective effects of EXS were linked to up-regulation of heme oxygenase-1(HO-1) and nuclear factor E2-related factor-2(Nrf-2) expression. EXS-induced HO-1 expression was significantly decreased in SnPP(HO-1 inhibitor)-and HO-1 siRNA-treated cells, whereas an increase was found in cobalt protoporphyrin IX(CoPP)(HO-1 inducer)-treated cells. In addition, pretreatment with EXS increased HO-1 and Nrf-2 expression under TNF-α stimulation with or without N-acetyl-L-cysteine. Furthermore, the inhibitory effects of EXS on TNF-α-induced vascular inflammation were partially reversed in SnPP-and of HO-1siRNA-treated cells but increased by CoPP.CONCLUSION: These results suggest that EXS may have important implications for prevention of vascular complications associated with vascular inflammation by inhibition of the NF-κB/ROS pathway and activation of the Nrf-2/HO-1 pathway.

Hwangryunhaedoktang exerts anti-inflammation on LPS-induced NO production by suppressing MAPK and NF-κB activation in RAW264.7 macrophages

OBJECTIVE： This study aimed to evaluate whether Hwangryunhaedoktang （HHT）, a herbal compound, has an inhibitory effect on lipopolysaccharide （LPS）-induced inflammation in RAW264.7 macrophages. METHODS： The effects of HHT were evaluated by confirming nitric oxide （NO） production and expression of inducible NO synthase （iNOS） and mitogen-activated protein kinases （MAPKs） in LPS-stimulated RAW264.7 macrophages via the Griess assay, Western blotting, and real-time reverse transcription quantitative polymerase chain reaction. Western blot analyses and luciferase assays were used to evaluate whether HHT has an effect on the phosphorylation and translocation of nuclear factor-κB （NF-κB）. The secretion and expression of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） were determined via enzyme-linked immunosorbent assay and Western blot analyses. RESULTS： HHT suppressed LPS-induced NO production and expression of iNOS in a dose-dependent manner. Additionally, MAPKs activation was also attenuated via inhibition of phosphorylation of extracellular signal-regulated kinases 1/2, c-Jun N-terminal kinase and p38 which were related to inflammatory pathway. Furthermore, HHT also effectively attenuated NF-κB activation and its translocation to the nucleus, a process that is closely linked to inflammation. LPS normally induced the expression of inflammatory cytokines such as TNF-α and IL-6, but the secretion and expression of TNF-α and IL-6 were significantly attenuated by pretreating the cells with HHT. CONCLUSION： HHT suppressed LPS-induced NO production by blocking the activation of NF-κB and MAPK signaling pathways in RAW264.7 macrophages. Furthermore, HHT may have an anti-inflammatory effect by suppressing the LPS-induced secretion of TNF-α and IL-6. Therefore, the traditional herbal formula HHT might be a useful potential therapeutic agent for inflammation.