Ginsenoside Rb1 inhibits tumor necrosis factor-alpha-induced vascular cell adhesion molecule-1 expression in human endothelial cells.
ABSTRACT We investigated whether ginsenoside Rb1 (Rb1) could block tumor necrosis factor-alpha (TNF-alpha)-induced over-expression of vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) and human lung microvascular endothelial cells (HMVECs-L). Cells were treated with various concentrations of TNF-alpha with or without Rb1 pre-treatment for 16 h. The mRNA and protein levels of VCAM-1 were determined with real-time polymerase chain reaction (PCR) and flow cytometry, respectively. Human monocytic THP-1 cells labeled with fluorescent dye (Calcein-AM) was used for the adhesion assay on HUVEC monolayers. Dihydroethidium (DHE) was used to demonstrate in situ levels of superoxide production. JC-1 dye was used to measure changes in mitochondrial membrane potential. Activation of mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-kappaB) was determined by Bio-Plex immunoassay. TNF-alpha treatment significantly increased the mRNA and protein levels of VCAM-1 in HUVECs in a dose dependent manner. Rb1 pre-treatment effectively blocked the TNF-alpha-induced expression of VCAM-1 mRNA or protein by 80% and 43%, respectively (p<0.01). THP-1 adhesion was also blocked. Furthermore, Rb1 reduced the TNF-alpha-induced increase of superoxide anion production by 41% and inhibited the TNF-alpha-induced decrease of mitochondrial membrane potential by 44% in HUVECs. Rb1 also effectively blocked TNF-alpha-induced activation of p38, c-Jun N-terminal protein kinase, extracellular signal-regulated kinase 1/2 and IkappaBalpha. In conclusion, Rb1 effectively blocked the TNF-alpha-induced over-expression of VCAM-1, increased THP-1 adhesion and over-production of superoxide anion. Furthermore, Rb1 inhibited TNF-alpha-induced MAPKs and NF-kappaB activation. These data suggested that Rb1 might have potential therapeutic effects in controlling inflammation in vascular diseases.
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ABSTRACT: The ligand ephrin Al is more often discussed to play a role in the development of the atherosclerotic plaque and in this context especially in the monocyte adhesion to endothelial cells. As tumor necrosis factor-alpha (TNF-alpha) is known to induce monocyte adhesion to endothelium and ephrin A1 expression, the present study focuses on the involvement of ephrin A1 in TNF-alpha-mediated monocyte adhesion. The analysis of different members of the Eph/ephrin system in TNF-alpha-treated human umbilical vein endothelial cells (HUVEC) revealed that especially ephrinAl was found to be highly regulated by TNF-alpha compared to other members of the Eph family. This effect is also present in arterial endothelial cells from the umbilical artery and from the coronary artery. This regulation is dependent on NF kappa B-activation as shown by the expression of a constitutive-active I kappa B-mutant By using siRNA-mediated silencing and adenoviral overexpression of ephrinA1 in HUVEC, the involvement of ephrinA1 in the TNF-alpha triggered monocyte adhesion to endothelial cells could be demonstrated. In addition, these results could be verified by quantitative adhesion measurement using atomic force microscopy-based single-cell force spectroscopy and under flow conditions. Furthermore, this effect is mediated via the EphA4 receptor. EphrinA1 does not influence the mRNA or protein expression of the adhesion receptors VCAM-1 and ICAM-1 in endothelial cells. However, the surface presentation of these adhesion receptors is modulated in an ephrinA1-dependent manner. In conclusion, these data demonstrate that ephrinA1 plays an important role in the TNF-alpha-mediated adhesion of monocytes to endothelial cells, which might be of great importance in the context of atherosclerosis.Journal of Molecular and Cellular Cardiology 10/2014; 77. DOI:10.1016/j.yjmcc.2014.10.010 · 5.22 Impact Factor
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ABSTRACT: Despite a multitude of reports on anti-inflammatory properties of ginseng extracts or individual ginsenosides, data on antiarthritic effect of ginseng saponin preparation with mixed ginsenosides is limited. On the other hand, a combined therapy of safe and inexpensive plant-derived natural products such as ginsenosides can be considered as an alternative to treat arthritis. Our previous in vitro data displayed a strong anti-inflammatory action of red ginseng saponin fraction-A (RGSF-A). We, herein, report a marked antiarthritic property of RGSF-A rich in ginsenoside Rb1, Rc, and Rb2. Collagen-induced arthritic (CIA) mice were treated with RGSF-A or methotrexate (MTX) for 5 weeks. Joint pathology, serum antibody production and leukocye activation, cytokine production in the circulation, lymph nodes, and joints were examined. RGSF-A markedly reduced severity of arthritis, cellular infiltration, and cartilage damage. It suppressed CD3(+)/CD69(+), CD4(+)/CD25(+), CD8(+) T-cell, CD19(+), B220/CD23(+) B-cell, MHCII(+)/CD11c(+), and Gr-1(+)/CD11b(+) cell activations. It further suppressed anti-CII- or anti-RF-IgG/IgM, TNF- α , IL-1 β , IL-17, and IL-6 secretions but stimulated IL-10 levels in the serum, joint, or splenocyte. RGSF-A attenuated arthritis severity, modified leukocyte activations, and restored cytokine imbalances, suggesting that it can be considered as an antiarthritic agent with the capacity to ameliorate the immune and inflammatory responses in CIA mice.Mediators of Inflammation 04/2014; 2014:748964. DOI:10.1155/2014/748964 · 2.42 Impact Factor
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ABSTRACT: Monocyte adhesion to activated vascular endothelial cells is the critical event in the initiation of atherosclerosis. Adhesion molecules are inflammatory markers, which are upregulated by oxidized low-density lipoprotein (ox-LDL) and play a pivotal role in atherogenesis. In present study, the effect of reinioside C, a major compound of Polygala fallax Hemsl., on adhesion of monocytes to endothelial cells induced by ox-LDL was investigated. The results showed that incubation of endothelial cells with ox-LDL (100 microg/mL) for 24 h markedly increased the expression of ICAM-1 and P-selectin and enhanced the adhesion of monocytes to endothelial cells. Pretreatment with reinioside C (1, 3, or 10 microM) dose-dependently decreased ox-LDL-induced upregulation of expression of ICAM-1 and P-selectin and the enhanced adhesion of monocytes to endothelial cells. To determine the role of NADPH oxidase/reactive oxygen species (ROS)/nuclear factor-kappaB (NF-kappaB) pathway, endothelial cells were treated with ox-LDL (100 microg/mL) for 2 h, and NADPH oxidase subunit (Nox 2 and p22phox) mRNA expression, intracellular ROS level, and NF-kappaB activity were measured. The results showed that reinioside C attenuated ox-LDL-induced NADPH oxidase subunit (Nox 2 and p22phox) mRNA expression, generation of ROS, and activation of NF-kappaB in endothelial cells in a dose-dependent manner; the two latter effects were inhibited by pyrollidine dithiocarbamate, the inhibitor of NF-kappaB. These findings suggest that reinioside C attenuates ox-LDL-induced expression of adhesion molecules (P-selectin and ICAM-1) and the adhesion of monocytes to endothelial cells by inhibiting NADPH oxidase/ROS/NF-kappaB pathway.Archiv für Experimentelle Pathologie und Pharmakologie 10/2009; 380(5):399-406. DOI:10.1007/s00210-009-0450-8 · 2.36 Impact Factor