大黄酸对肿瘤坏死因子-α诱导的脐静脉内皮细胞黏附作用影响的观察

目的 观察不同剂量的大黄酸(Rhein)对TNF-α诱导的人脐静脉内皮细胞(HUVECs)黏附作用的影响. 方法 将HUVECs分为单纯HUVECs组、单纯TNF-α 40 ng/ml(TNF-α)组、Rhein100 μg/ml+TNF-α 40 ng/ml(Rhein100)组、Rhein 50 μg/ml+TNF-α 40 ng/ml(Rhein50)组、Rhein 10 μg/ml+TNF-α 40 ng/ml (Rhein10)组.采用Western blot和RT-PCR检测HUVECs细胞间黏附因子-1(ICAM-1)的蛋白和mRNA的水平.采用人单核细胞株(THP-1)和HUVECs的黏附性实验检测内皮细胞的黏附功能. 结果 与TNF-α组比较,Rhein100、Rhein50、Rhein10组ICAM-1蛋白相对表达量下降[(2.88±0.04)vs(1.27±0.32),(1.28±0.17),(1.32±0.25),P＜0.05或P＜ 0.01];Rhein100和Rhein50组ICAM-1 mRNA的水平下降[(2.12±0.24)vs(1.19±0.17),(1.26±0.23),P＜0.05或P＜0.01];在黏附性实验中,Rhein100组HUVECs所黏附的单核细胞数目下降[(1.28±0.07)vs(1.07±0.14),P＜0.01]. 结论 Rhein能抑制TNF-α所诱导的HUVECs的ICAM-1的过度表达,可能是Rhein对HUVECs的保护机制之一.     

肿瘤坏死因子α致HUVECs内皮型一氧化氮合酶降解

目的研究肿瘤坏死因子-α(TNF-α)是否可以通过细胞内蛋白质降解途径引起人脐静脉内皮细胞(HUVECs)内皮型一氧化氮合酶(eNOS)的蛋白量减少。方法建立原代HUVECs培养,选取TNF-α不同浓度(0.01、0.1、1和10 ng/m L)、不同时间(24、48和72 h)处理HUVECs;溶酶体抑制剂氯化铵(NH4Cl)、caspase抑制剂(caspase inhibitor)和泛素-蛋白酶体抑制剂(MG-132)预处理HUVECs 1.5 h后加入TNF-α(1 ng/m L)共处理24 h,Western blot方法检测HUVECs中eNOS蛋白表达。结果与对照组比较,1 ng/m L TNF-α处理细胞24 h,eNOS蛋白量明显减少(P0.01);MG-132与TNF-α共处理组,eNOS蛋白量明显增加(P0.01)。结论 TNF-α可以通过泛素-蛋白酶体途径引起eNOS蛋白降解。     

糖基化终产物对人脐静脉内皮细胞血管内皮生长因子mRNA及蛋白表达的影响

目的研究糖基化终产物（AGEs）对人脐静脉山皮细胞血管内皮生长凼子（VEGF）mRNA及蛋白表达的影响，探讨AGEs在糖尿病动脉粥样硬化中的作用。方法将人脐静脉内皮细胞株ECV304用BSA及小同浓度的AGEs孵育24h及400mg／L的AGEs孵育0、12、24及36h，采用原位杂交及Westem blot方法检测VEGFmRNA及蛋白的表达。结果人脐静脉内皮细胞在100、200及400mg／LAGEs孵育24h后，VEGFmRNA及蛋白表达均显著高于BSA对照组（P〈0．05），在用400mg／LAGEs分别孵育12．24及36h后，各组内皮细胞VEGF mRNA及蛋白表达量也明显高于0h对照组（P〈O．05）。结论AGEs可增加人脐静脉内皮细胞VEGF mRNA及蛋白的表达，且与浓度和时间呈正相关。     

肿瘤血管靶向肽GX1的受体筛选

目的：筛选肿瘤血管靶向肽GX1（CGNSNPKSC）的受体。方法：化学合成生物素标记的GX1,分离培养原代人脐静脉内皮细胞（HUVECs）,培养并收集共培养人脐静脉内皮细胞（co-HUVECs）全蛋白;应用免疫沉淀、免疫磁珠法分离富集与GX1结合的蛋白质;采用银染检测,确定并获取特异性蛋白条带;利用基质辅助激光解析电离飞行时间质谱（MALD I-TOF-MS）及生物信息学分析,对条带蛋白进行测序和分析。结果：免疫沉淀和银染法获得与GX1特异性结合的蛋白条带,其分子量在10-15KDa之间。利用MALDI-TOF-MS及生物信息学分析获得了一个有意义的候选蛋白核苷二磷酸激酶A（NDPKA）。结论：利用免疫沉淀-质谱法筛选获得了GX1受体的候选蛋白,为研究GX1的作用机制奠定了基础。     

Dual functions of ginsenosides in protecting human endothelial cells against influenza H9N2-induced inflammation and apoptosis

Ethnopharmacological relevance

Panax ginseng is a precious traditional Chinese herbal medicine which has been utilized as herbal tonic for improving immunity. The active component, ginsenosides have been shown to possess various pharmacological functions including immunomodulation and cardiovascular protection.

Aim of the study

To investigate the immunomodulatory effect and anti-apoptotic effect of ginsenosides on avian influenza-infected human endothelial cells, and to present evidence for the cardiovascular protection by ginseng during influenza infection.

Materials and methods

Human umbilical vein endothelial cells (HUVECs) were infected with avian influenza H9N2/G1 to induce IP-10 production and cell death, cells were then incubated with ginsenosides PPT and Re. The level of IP-10 and microRNA was determined by ELISA and real-time PCR respectively. Cell death was determined by MTT, TUNEL and flow cytometry.

Results

Ginsenoside metabolite protopanaxatriol showed significant suppression effect on IP-10 production upon H9N2/G1 infection through up-regulation of miR-15b expression. In addition, ginsenoside-induced cytoprotection was reflected in the increase of cell viability. Data from flow cytometry analysis and TUNEL assay also showed that ginsenoside Re could protect ECs from H9N2/G1-induced apoptosis and DNA damage.

Conclusions

This report further supports the traditional belief for immunomodulatory effects of ginseng, also demonstrated the partial protective mechanism of ginsenosides on avian influenza infection and its related endothelial dysfunction.     

Inhibitory effects of Physalis angulata on tumor metastasis and angiogenesis

Ethnopharmacological relavence

Physalis angulata is well-known in traditional Chinese medicine as a ingredient for various herbal formulation; also, it has been shown to exhibit anti-cancer and anti-inflammatory effects. In this study, the ability of P. angulata to inhibit tumor metastasis and angiogenesis was investigated.

Materials and methods

Anti-proliferative activity of ethyl acetate extracts of P. angulata (PA extracts), was determined against human oral squamous carcinoma (HSC-3) and human umbilical vein endothelial cells (HUVECs) by trypan blue exclusion method. Wound-healing migration, trans-well invasion, Western blotting and chick chorioallantoic membrane assay were carried out to determine the anti-metastatic and anti-angiogenic effects of PA extracts in vitro and in vivo.

Results

We demonstrated that at sub-cytotoxic concentrations of PA extracts (5-15 μg/mL) markedly inhibited the migration and invasion of highly metastatic HSC-3 cells as shown by wound-healing repair assay and trans-well assay. Gelatin zymography assay showed that PA extracts suppressed the activity of matrix metalloproteinase (MMP)-9 and -2, and urokinase plasminogen activator (u-PA) in HSC-3 cells. In addition, Western blot analysis confirmed that PA extracts significantly decreased MMP-2 and u-PA protein expression in HSC-3 cells. Notably, PA extracts significantly augmented the expression of their endogenous inhibitors, including tissue inhibitors of MMP (TIMP-1 and -2), and plasminogen activator inhibitors (PAI-1 and -2). Further investigations revealed that non-cytotoxic concentration of PA extracts (5-15 μg/mL) inhibited vascular endothelial growth factor (VEGF)-induced proliferation, and migration/invasion of HUVECs in vitro. PA extracts also suppressed the activity of MMP-9, but not MMP-2, in HUVECs. Further, we observed, PA extracts strongly suppressed neovessel formation in the chorioallantoic membrane of chick embryos in vivo.

Conclusions

These results strongly support an anti-metastatic and anti-angiogenic activity of P. angulata that may contribute to the development of better chemopreventive agent for cancer and inflammation.     

Toona sinensis (leaf extracts) inhibit vascular endothelial growth factor (VEGF)-induced angiogenesis in vascular endothelial cells

Aim of the study

Toona sinensis is well known as a traditional Chinese medicine; also, it has been shown to exhibit anticancer and anti-inflammatory effects. This study was aimed at evaluating the anti-angiogenesis effect of the aqueous extracts of Toona sinensis (TS extracts) or gallic acid, a major component of TS extracts, against both VEGF-induced EA.hy 926 and human umbilical vein endothelial cells (HUVECs).

Materials and methods

Anti-proliferative activity of TS extracts or gallic acid, was determined against EA.hy 926 and HUVECs by trypan blue exclusion method. Invasion, tube formation and chick chorioallantoic membrane assay were carried out to determine the in vitro and in vivo anti-angiogenic effects.

Results

Non-cytotoxic concentration of TS extracts (50-100 μg/mL) and gallic acid (5 μg/mL) inhibited the proliferation of VEGF-stimulated EA.hy 926 and HUVECs. Inhibitory effects of TS extracts and gallic acid on angiogenesis were assessed by VEGF-induced migration/invasion and capillary-like tube formation by EA.hy 926 and HUVECs. Additionally, gelatin zymography assays showed that TS extracts and gallic acid suppressed the activity of metalloproteinase (MMP)-9 and MMP-2 activated by VEGF. In vivo, TS extracts and gallic acid strongly suppressed neovessel formation in the chorioallantoic membrane of chick embryos. Flow cytometry analyses and Western blot demonstrated that treatment with TS extracts and gallic acid induced G₀/G₁ arrest in VEGF-stimulated EA.hy 926 cells via a reduction in the amounts of cyclin D1, cyclin E, CDK4, hyperphosphorylated retinoblastoma protein (pRb), VEGFR-2, and eNOS.

Conclusions

These results support an anti-angiogenic activity of Toona sinensis that may contribute critically to its cancer and inflammation chemopreventive potentials.     

Methyl-β-cyclodextrin suppresses the monocyte-endothelial adhesion triggered by lipopolysaccharide (LPS) or oxidized low-density lipoprotein (oxLDL)

ContextRecent studies demonstrated the anti-atherosclerotic efficacy of cyclodextrin. However, it remains unclear whether cyclodextrin exerts the anti-atherosclerotic effect via regulating monocyte-endothelial adhesion.ObjectiveTo answer that question by recruiting methyl-β-cyclodextrin (MβCD) as a cyclodextrin representative.Materials and methodsHuman umbilical vein endothelial cells (HUVECs) were not treated, or treated with 1 µg/mL liposaccharide (LPS) or 50 µg/mL oxidized low-density lipoprotein (oxLDL) for 12 h, 5 mM MβCD for 1 h, and LPS/oxLDL (1 and 50 µg/mL, respectively for 12 h) plus MβCD (5 mM for 1 h), respectively. The effects of MβCD on LPS/oxLDL-triggered monocyte-endothelial adhesion and related molecules in signalling pathways were evaluated via confocal microscopy, flow cytometry, RT-PCR, western blotting, and cell adhesion assay.ResultsMβCD with an IC₅₀ of 27.66 mM (1 h treatment) exerted no significant cytotoxicity at ≤5 mM for ≤2 h. Compared with the control, both LPS and oxLDL induced an ∼2–3-fold increase in adhesion molecule expression (ICAM-1 and VCAM-1 at protein and mRNA levels) and NF-κB phosphorylation (p-NF-κB/pP65), an increase in IκB kinase (IKK), and a decrease in phosphorylated protein kinase B (p-Akt), respectively. Moreover, more monocytes (2-fold higher for LPS and 15% higher for oxLDL) were attached on LPS/oxLDL-stimulated HUVECs. 5 mM MβCD reversed the LPS/oxLDL-induced changes back to the control levels.ConclusionsMβCD significantly suppresses the LPS/oxLDL-triggered monocyte-endothelial adhesion by downregulating adhesion molecule expression probably via LPS-IKK-NF-κB or oxLDL-Akt-NF-κB pathway. This study demonstrates a potential mechanism of the anti-atherosclerotic efficacy of cyclodextrin from the angle of monocyte-endothelial adhesion.