Effect of Benincasa hispida Cogniaux on high glucose-induced vascular inflammation of human umbilical vein endothelial cells

Vascular inflammation is an important factor which can promote diabetic complications. Preliminary investigations of several crude plant extracts including aqueous extract of Benincasa hispida Cogniaux exhibit anti-inflammatory properties. This study investigates the mechanism of anti-vascular inflammatory activity of an aqueous extract of B. hispida Cogniaux (ABH) in human umbilical vein endothelial cells (HUVECs). The study was performed on HUVECs that were pretreated with various concentrations (1–20 µg/ml) of ABH before exposure with high glucose (25 mM) for 48 h. Cell ELISA and Western blot analysis showed that ABH inhibited high glucose-induced cell adhesion molecules (CAMs) surface and protein expression, resulting in reduced adhesion of U937 monocytes. ABH also inhibited the mRNA expression level of monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8). High glucose-induced ROS production was inhibited by treatment of ABH. We observed that pretreatment with HUVECs with ABH blocks NF-κB activation via blocking phosphorylation and degradation of its inhibitory protein, IκB-α. ABH also reduced NF-kB promoter activity. These results suggest that ABH reduces high glucose-induced CAMs activation by inhibiting monocyte adhesion, ROS, and NF-κB in HUVECs.     

Effect of Zanthoxylum schinifolium on TNF-α-induced vascular inflammation in human umbilical vein endothelial cells

Pro-inflammatory cytokines induce the injury of endothelial cells in response to increases of adhesion molecules, leading to vascular inflammation and the development of atherosclerosis. In this study, we evaluated an ethanol extract of Zanthoxylum schinifolium (EZS) to determine if it inhibits the expressions of cellular adhesion molecules in human umbilical vein endothelial cells (HUVEC). When pretreatment of HUVEC with EZS, EZS suppressed the expression levels of cell adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin induced by TNF-α. The adhesion of HL-60 cells to TNF-α-induced endothelial cells was decreased significantly in a concentration-dependent manner. Furthermore, TNF-α-induced MCP-1 and IL-8 mRNA expression levels were also attenuated by pretreatment with EZS. In addition, EZS suppressed TNF-α-induced production of reactive oxygen species (ROS). EZS inhibited NF-κB activation and IκB-α phosphorylation induced by TNF-α, subsequent degradation of IκB-α. Finally, EZS inhibited TNF-α-induced p38 MAPK and c-Jun N-terminal kinase (JNK) phosphorylation. Taken together, these results demonstrate that EZS suppresses vascular inflammatory process, which may be closely related to the inhibition of ROS, JNK, p38 MAPK and NF-κB activation in HUVEC.     

Scutellarin isolated from Erigeron multiradiatus inhibits high glucose-mediated vascular inflammation

Erigeron multiradiatus (Lindl.) Benth is a traditional Tibetan medicine herb long used to treat various diseases related to inflammation. Our previous phytochemical studies on E. multiradiatus resulted in the isolation of scutellarin, which is a known flavone glucuronide with comprehensive pharmacological actions. In present study, we investigated the inhibition action of scutellarin on high glucose-induced vascular inflammation in human endothelial cells (ECV304 cells). Consistent with previous reports, exposure of ECV304 cells to high glucose for 24 h caused an increase of intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein 1 (MCP-1), and promoted cell adhesion between monocyte and ECV304 cells. However, pretreatment with scutellarin (0.1 and 1 microM) reversed these effects in a concentration-dependent manner. Scutellarin was able to inhibit the activation of NF-kappaB induced by high glucose in ECV304 cells. Furthermore, although oral administration of scutellarin (10 and 50 mg/kg) did not produce significant antihyperglycemic action, it lowered the serum MCP-1 levels significantly in alloxan-induced diabetic mice. Therefore, our results suggest that scutellarin has anti-inflammation effect that may afford some protection against hyperglycemia-induced vascular inflammatory both in vitro and in vivo.     

Coenzyme Q10 prevents high glucose-induced oxidative stress in human umbilical vein endothelial cells

Hyperglycemia-induced oxidative stress plays a crucial role in the pathogenesis of vascular complications in diabetes. Although some clinical evidences suggest the use of an antioxidant reagent coenzyme Q10 in diabetes with hypertension, the direct effect of coenzyme Q10 on the endothelial functions has not been examined. In the present study, we therefore investigated the protective effect of coenzyme Q10 against high glucose-induced oxidative stress in human umbilical vein endothelial cells (HUVEC). HUVEC exposed to high glucose (30 mM) exhibited abnormal properties, including the morphological and biochemical features of apoptosis, overproduction of reactive oxygen species, activation of protein kinase Cbeta2, and increase in endothelial nitric oxide synthase expression. Treatment with coenzyme Q10 strongly inhibited these changes in HUVEC under high glucose condition. In addition, coenzyme Q10 inhibited high glucose-induced cleavage of poly(ADP-ribose) polymerase, an endogenous caspase-3 substrate. These results suggest that coenzyme Q10 prevents reactive oxygen species-induced apoptosis through inhibition of the mitochondria-dependent caspase-3 pathway. Moreover, consistent with previous reports, high glucose caused upregulation of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in HUVEC, and promoted the adhesion of U937 monocytic cells. Coenzyme Q10 displayed potent inhibitory effects against these endothelial abnormalities. Thus, we provide the first evidence that coenzyme Q10 has a beneficial effect in protecting against the endothelial dysfunction by high glucose-induced oxidative stress in vitro.     

壳聚糖抑制高糖诱导的脂质过氧化及血管内皮细胞与单核细胞黏附

目的研究壳聚糖(chitosan)对高糖诱导细胞产生脂质过氧化及血管内皮细胞与单核细胞黏附的抑制作用。方法建立人脐静脉血管内皮细胞(HUVEC)高糖培养模型,实验分空白对照组、高糖模型组、高糖+壳聚糖组,测定细胞产生羟自由基(OH.)及脂质过氧化产物丙二醛(MDA)量;同时取单核巨噬细胞系Raw264.7,以荧光染料Rhodamin123孵育后加入以上各组,荧光摄像及比色检测单核细胞黏附数量;RT-PCR法检测血管细胞黏附分子(VCAM-1)mRNA变化。结果与空白对照组比较,高糖引起HUVEC产生OH.及MDA含量增加,黏附于HUVEC的Raw264.7数量以及VCAM-1表达升高;壳聚糖可呈浓度依赖性地抑制上述现象,但对细胞存活无明显影响。结论壳聚糖可能通过减轻自由基与脂质过氧化损伤,下调血管内皮细胞VCAM-1的表达,从而抑制高糖诱导的单核细胞与内皮细胞黏附。     

Geniposide inhibits high glucose-induced cell adhesion through the NF-KB signaling pathway in human umbilical vein endothelial cells

Aim:

To investigate whether geniposide, an iridoid glucoside extracted from gardenia jasminoides ellis fruits, inhibits cell adhesion to human umbilical vein endothelial cells (HUVECs) induced by high glucose and its underlying mechanisms.

Methods:

HUVECs were isolated from human umbilical cords and cultured. The adhesion of monocytes to HUVECs was determined using fluorescence-labeled monocytes. The mRNA and protein levels of vascular cell adhesion molecule-1 (VCAM-1) and endothelial selectin (E-selectin) were measured using real-time RT-PCR and ELISA. Reactive oxygen species (ROS) production was measured using a fluorescent probe. The amounts of nuclear factor-kappa B (NF-κB) and inhibitory factor of NF-κB (IκB) were determined using Western blot analysis. The translocation of NF-κB from the cytoplasm to the nucleus was determined using immunofluorescence.

Results:

Geniposide (10–20 μmol/L) inhibited high glucose (33 mmol/L)-induced adhesion of monocytes to HUVECs in a dose-dependent manner. This compound (5–40 μmol/L) also inhibited high glucose-induced expression of VCAM-1 and E-selectin at the gene and protein levels. Furthermore, geniposide (5–20 μmol/L) decreased ROS production and prevented IκB degradation in the cytoplasm and NF-κB translocation from the cytoplasm to the nucleus in HUVECs.

Conclusion:

Geniposide inhibits the adhesion of monocytes to HUVECs and the expression of CAMs induced by high glucose, suggesting that the compound may represent a new treatment for diabetic vascular injury. The mechanism underlying this inhibitory effect may be related to the inhibition of ROS overproduction and NF-κB signaling pathway activation by geniposide.     

Endothelial cell adhesion molecules and cancer progression

The role of cell adhesion molecules (CAMs), such as intercellular cell adhesion molecule-1 (ICAM-1), vascular endothelial cell adhesion molecule-1 (VCAM-1), E-selectin, and P-selectin, has been studied extensively in the process of inflammation. These molecules are responsible for recruiting leukocytes onto the vascular endothelium before extravasation to the injured tissues. Some circulating cancer cells have been shown to extravasate to a secondary site using a process similar to inflammatory cells. The most studied ligands for CAMs expressed on cancer cells, sialyl Lewis (a/x) antigens, are shown to be involved in adhesion to endothelial cells by binding to E-selectin. This process, shared by inflammatory cells and cancer cells, may partially explain the link between inflammation and tumorigenesis. Furthermore, this process may elucidate the therapeutic benefit of anti-inflammatory drugs in cancer treatment. The complexity of the tumor microenvironment has been revealed in the past decade. Currently, intense investigation is aimed at various aspects of the tumor microenvironment in addition to the tumor cells themselves. Here, we review the role of CAMs in extravasation of circulating cancer cells, a key step in metastasis.     

Inhibition of tumor necrosis factor-alpha-induced expression of adhesion molecules in human endothelial cells by the saponins derived from roots of Platycodon grandiflorum

Adhesion molecules play an important role in the development of atherogenesis and are produced by endothelial cells after being stimulated with various inflammatory cytokines. This study examined the effect of saponins that were isolated from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil saponins (CKS), on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. CKS significantly inhibited the TNFalpha-induced increase in monocyte adhesion to endothelial cells as well as decreased the protein and mRNA expression levels of vascular adhesion molecule-1 and intercellular cell adhesion molecule-1 on endothelial cells. Furthermore, CKS significantly inhibited the TNFalpha-induced production of intracellular reactive oxygen species (ROS) and activation of NF-kappaB by preventing IkappaB degradation and inhibiting IkappaB kinase activity. Overall, CKS has anti-atherosclerotic and anti-inflammatory activity, which is least in part the result of it reducing the cytokine-induced endothelial adhesion to monocytes by inhibiting intracellular ROS production, NF-kappaB activation, and cell adhesion molecule expression in endothelial cells.     

Aldosterone impairs vascular endothelial cell function

Aldosterone is a mineralocorticoid hormone that plays an important role in regulating electrolyte balance and blood pressure and also participates in endothelial dysfunction. We evaluated the direct effect of aldosterone on human umbilical vein cells (HUVEC). Levels of eNOS phosphorylation by vascular endothelial growth factor were diminished, and the amount of NO produced in response to vascular endothelial growth factor measured as NO2+NO3 was significantly decreased in cells previously incubated with aldosterone. Incubation with aldosterone for 24 h dose-dependently increased Nox4 mRNA expression in HUVEC. Although NF-kappaB was not apparently activated by aldosterone, mRNA levels of vascular cell adhesion molecule-1, E-selectin, monocyte chemotactic protein-1, and intercellular adhesion molecule-1 in HUVEC were significantly increased after incubation with aldosterone. Thus, aldosterone directly causes the dysregulation of endothelial cell function, which may be partly responsible for high blood pressure and atherosclerosis.     

Rhodostomin inhibits thrombin-enhanced adhesion of ROS 17/2.8 cells through the blockade of alphavbeta3 integrin.

Osteosarcoma is a very malignant bone tumor which has a high metastatic potential and usually lead to poor prognosis. The adhesion of tumor cells to the endothelium or extracellular matrix (ECM) is an essential step in the metastatic cascade. We investigated the effect of thrombin on the adhesion activity of the osteosarcoma cell line, ROS 17/2.8. Incubation with the low concentrations of thrombin (0.01-5 U/ml, 5 min to 24 h) elevated the adhesion activity of ROS 17/2.8 to both human umbilical vein endothelial cells (HUVEC) and extracellular matrix, with the peak effect at the concentration of 0.5 U/ml for 30 min at 37 degrees C. The ROS 17/2.8 cells responded to thrombin by a peak effect of increased adhesion to HUVEC (5.5 folds vs. control) and fibronectin (4.8 folds) after thrombin pretreatment (0.5 U/ml, 30 min, 37 degrees C). Pretreatment with monoclonal antibodies against beta3 integrins, including anti-alphavbeta3, 10E5 and 7E3, effectively antagonized the thrombin-enhanced cell adhesion activity, whereas anti-alpha3beta1 and anti-alpha5beta1 did not antagonize the enhanced cell adhesion. Rhodostomin, an Arg-Gly-Asp (RGD)-containing snake venom peptide, and synthetic peptide RGDS also blocked the thrombin-enhanced ROS 17/2.8 cell adhesion. This study demonstrated that thrombin enhanced the cell adhesion of ROS 17/2.8 cells to HUVEC or ECM through an upregulation of beta3 integrins, and rhodostomin was a strong inhibitor on thrombin-enhanced cell adhesion, either to HUVEC or fibronectin substratum.     

Ethyl pyruvate modulates acute inflammatory reactions in human endothelial cells in relation to the NF-kappaB pathway

BACKGROUND AND PURPOSE: Endothelial cell activation plays a critical role in regulating leukocyte recruitment during inflammation and infection. Ethanol (EtOH) reduces host defence systems, including cell adhesion. However, well-known side effects of EtOH limit its clinical use as an anti-inflammatory drug. Instead, ethyl pyruvate (EtP) may represent a better alternative. Here, we compared effects of EtP and EtOH on neutrophil recruitment and activation of human umbilical vein endothelial cells (HUVECs). EXPERIMENTAL APPROACH: Adhesion of neutrophils to HUVEC monolayers, surface expression of intercellular cell adhesion molecule, E-selectin, vascular cell adhesion molecule, release of interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF) from HUVECs were assessed as well as translocation of interleukin-1 receptor-associated kinase (IRAK-1), the nuclear factor-kappa B (NF-kappaB) subunits p50, p65 and IkappaB-alpha. NF-kappaB activation was analysed with a luciferase reporter plasmid. Cells were stimulated with IL-1beta, lipopolysaccharide (LPS) or tumour necrosis factor-alpha.Key results:EtP was several-fold more potent than EtOH in reducing adhesion of neutrophils to activated HUVECs, generation of IL-8 or G-CSF and surface expression of the adhesion molecules. This last reaction was decreased by EtP even when added after cytokines or LPS. Translocation of IRAK-1, IkappaBalpha and the NF-kappaB p65 subunit to the HUVEC nucleus was inhibited by EtP for all stimuli, whereas the diminished p50 translocation was stimulus specific. When p65 was constitutively expressed in Cos7 cells, stimulation of an NF-kappaB-dependent reporter gene was not affected by EtP, suggesting that EtP acted upstream of gene activation. CONCLUSIONS AND IMPLICATIONS: EtP impedes adhesive, secretory and signalling events typical of the early inflammatory response in endothelial cells, suggesting EtP as a possible treatment for acute inflammatory conditions.     

波动性高糖对人脐静脉内皮细胞炎症因子表达的影响

目的研究体外波动性和持续性高糖对人脐静脉内皮细胞（human umbilical vein endothelial cells,HUVEC）炎症因子表达的影响。方法分别在正常葡萄糖（5.5 mmol/L,NG）、持续性高糖（25 mmol/L,PHG）、波动性高糖（5.5 mmol/L和25 mmol/L葡萄糖每24 h交替,OHG）和波动性高渗环境（不加入葡萄糖,加入不同量甘露醇控制渗透压与波动性高糖组一致,OC）中连续培养HUVEC 7d。采用ELISA法和实时定量PCR法分别检测HUVEC在不同血糖环境中白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）和细胞间黏附因子-1（ICAM-1）中蛋白和mRNA的表达。结果与NG组和OC组比较,发现持续性高糖可以显著升高HUVEC的IL-6、TNF-α和ICAM-1蛋白表达（P〈0.05）,而波动性高糖可以进一步放大这种差异（P〈0.05）。在mRNA水平,PHG组较NG组和OC组显著增加IL-6、TNF-α和ICAM-1表达（P〈0.05）,而这一趋势在波动性高糖组最为明显（P〈0.05）。结论持续性高糖可以显著增强HUVEC炎症反应,而波动性高糖进一步放大这一效应。     

High glucose stimulates TNFα and MCP-1 expression in rat microglia via ROS and NF-κB pathways

Aim:

To investigate whether high glucose stimulates the expression of inflammatory cytokines and the possible mechanisms involved.

Methods:

ELISA and real-time PCR were used to determine the expression of the inflammatory factors, and a chemiluminescence assay was used to measure the production of reactive oxygen species (ROS).

Results:

Compared to low glucose (10 mmol/L), treatment with high glucose (35 mmol/L) increased the secretion of tumor necrosis factor (TNF)α and monocyte chemotactic protein-1 (MCP-1), but not interleukin (IL)-1β and IL-6, in a time-dependent manner in primary cultured rat microglia. The mRNA expression of TNFα and MCP-1 also increased in response to high glucose. This upregulation was specific to high glucose because it was not observed in the osmotic control. High-glucose treatment stimulated the formation of ROS. Furthermore, treatment with the ROS scavenger NAC significantly reduced the high glucose-induced TNFα and MCP-1 secretion. In addition, the nuclear factor kappa B (NF-κB) inhibitors MG132 and PDTC completely blocked the high glucose-induced TNFα and MCP-1 secretion.

Conclusion:

We found that high glucose induces TNFα and MCP-1 secretion as well as mRNA expression in rat microglia in vitro, and this effect is mediated by the ROS and NF-κB pathways.     

Inhibition of γ-irradiation induced adhesion molecules and NO production by alginate in human endothelial cells

Inflammation is a frequent radiation-induced reaction following therapeutic irradiation. Treatment of human umbilical endothelial cells (HUVEC) with gamma-irradiation (gammaIR) induces the expression of adhesion proteins such as intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. Since the upregulation of these proteins on endothelial cell surface has been known to be associated with inflammation, interfering with the expression of adhesion molecules is an important therapeutic target. In the present study, we demonstrate that high mannuronic acid-containing alginate (HMA) inhibits gammaIR induced expression of ICAM-1, VCAM-1, and E-selectin on HUVEC in a dose dependent manner. HMA also inhibited gammaIR induced production of Nitric oxide (NO). These data suggest that HMA has therapeutic potential for the treatment of various inflammatory disorder associated with an increase of endothelial leukocyte adhesion molecules.     

Blockade of nitroxidative stress by roasted licorice extracts in high glucose-exposed endothelial cells

Diabetes can cause a wide variety of vascular complications and endothelial dysfunction. In this study, human vascular endothelial cells were exposed to 5.5 mM and 33 mM glucose for 5 d in the absence and presence of 1 to 20 mug/mL roasted licorice (Glycyrrhiza inflata Bat.) ethanol extracts (rLE). Caspase-3 activation and Annexin V staining revealed that high glucose induced endothelial apoptotic toxicity with a generation of reactive oxygen species (ROS) and these effects were reversed by rLE at >/=1 mug/mL in a dose-dependent manner. Cytoprotective rLE substantially reduced high glucose-induced expression of endothelial nitric oxide synthase (eNOS), and hence attenuated the formation of peroxynitrite radicals derived from NO. In addition, rLE suppressed expression of PKCbeta2 and activation of NADPH oxidase subunit of p22phox promoted by high glucose. However, rLE 相似文献   

TiO₂ nanoparticles induce dysfunction and activation of human endothelial cells

Nanoparticles can reach the blood and cause inflammation, suggesting that nanoparticles-endothelial cells interactions may be pathogenically relevant. We evaluated the effect of titanium dioxide nanoparticles (TiO?) on proliferation, death, and responses related with inflammatory processes such as monocytic adhesion and expression of adhesion molecules (E- and P-selectins, ICAM-1, VCAM-1, and PECAM-1) and with inflammatory molecules (tissue factor, angiotensin-II, VEGF, and oxidized LDL receptor-1) on human umbilical vein endothelial cells (HUVEC). We also evaluated the production of reactive oxygen species, nitric oxide production, and NF-κB pathway activation. Aggregates of TiO? of 300 nm or smaller and individual nanoparticles internalized into HUVEC inhibited proliferation strongly and induced apoptotic and necrotic death starting at 5 μg/cm2. Besides, TiO? induced activation of HUVEC through an increase in adhesion and in expression of adhesion molecules and other molecules involved with the inflammatory process. These effects were associated with oxidative stress and NF-κB pathway activation. In conclusion, TiO? induced HUVEC activation, inhibition of cell proliferation with increased cell death, and oxidative stress.