当归挥发油对人脐静脉内皮细胞增殖作用的谱效关系

目的:探讨不同产地当归挥发油与人脐静脉内皮细胞增殖作用的相关关系。方法:利用水蒸气蒸馏法提取当归挥发油,采用GC-MS联用分析技术建立44批不同产地当归药材挥发油指纹图谱,质谱检索库及保留指数法鉴定各色谱峰所示化学成分,用噻唑蓝染色(MTT)实验考察不同产地当归挥发油对HUVECs细胞的增值率,再通过线性回归分析方法,建立并分析当归挥发油促HUVECs细胞增殖作用的相关关系。结果:通过线性回归分析得色谱峰X_1,X_2与细胞增殖率呈负相关的关系,其余色谱峰与细胞增殖率均呈正相关的关系,且其中X_3,X_6,X_7号色谱峰回归系数较大,是当归挥发油促HUVECs细胞增殖的主要化学成分。结论:该方法能快速、有效地建立当归挥发油谱效相关关系,可为当归挥发油化学成分药理性质的研究提供参考依据。     

川芎嗪与黄芪甲苷配伍对人脐静脉内皮细胞血管生成的作用及机制探讨

目的研究川芎嗪与黄芪甲苷配伍对缺氧诱导损伤的人脐静脉内皮细胞(HUVECs)的增殖的影响及机制。方法建立HUVECs缺氧损伤模型,将细胞分为5组,对照组、模型组、川芎嗪(80μg/mL)组、黄芪甲苷(40μg/mL)组及川芎嗪(80μg/mL)+黄芪甲苷(40μg/mL)组,MTT法检测川芎嗪、黄芪甲苷及其配伍对缺氧损伤HUVECs增殖的影响;免疫组化法检测缺氧损伤HUVECs细胞VEGF、Ang-II蛋白表达,Western blotting检测VEGF和Ang-II蛋白的表达,RT-PCR检测VEGF和Ang-II mR NA表达。结果与模型组相比,川芎嗪与黄芪甲苷均能提高细胞存活率,川芎嗪与黄芪甲苷配伍组具有极显著差异(P0.001);川芎嗪与黄芪甲苷配伍提高VEGF、Ang-II蛋白表达。同时,川芎嗪与黄芪甲苷配伍组能上调VEGF和Ang-II mR NA的表达(P0.001)。结论川芎嗪与黄芪甲苷配伍可能通过增加血管生成靶向因子VEGF和Ang-II的表达发挥促进血管生成的作用。     

Paeoniflorin protects HUVECs from AGE-BSA-induced injury via an autophagic pathway by acting on the RAGE

The aim of our study was to investigate the protective effects of Paeoniflorin (PF) against injury induced by AGE-modified bovine serum albumin (AGE-BSA) in human umbilical vein endothelial cells (HUVECs), and to examine the underlying mechanisms of these effects. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to determine cell viability. Protein expression levels were determined by western blotting. For function-blocking experiments, we used small interfering RNA molecules (siRNA) for function-blocking experiments. At 6 h, we found that 100 μg/mL AGE-BSA reduced the viability of HUVECs. However, pretreatment with PF restored cell viability in a dose-dependent manner. AGE-BSA increased the levels of microtubule-associated protein light chain 3-II (LC3-II) and the receptor for advanced glycation end products (RAGE). Expression of p62 protein was also increased, but not at a statistically significant level. Pretreatment with PF further increased levels of LC3-II and RAGE, but reduced the expression of p62. In cells transfected with Atg5 and RAGE siRNA, cell viability and expression of LC3-II decreased in both the AGE-BSA and PF + AGE-BSA treatments. PF can protect HUVECs from AGE-BSA-induced injury by upregulating autophagy and promoting the completion of autophagy flux. RAGE plays an important role in this autophagic protection effect.     

Protective effects of isorhamnetin on apoptosis and inflammation in TNF-α-induced HUVECs injury

Little is known about the role of isorhamnetin on endothelial cell apoptosis and inflammation when insulted by TNF-α injury. In our study, HUVECs were treated with TNF-α for 6 hours. HUVECs apoptosis were detected using flow cytometry. The expressions of ICAM-1, VCAM-1, E-selectin, NF-κB, AP-1 and eNOS were determined with western blotting or flow cytometry. The results showed TNF-α increased of apoptosis and the expression of ICAM-1, VCAM-1 and E-selectin in HUVECs, accompanied by significant augmentation of NF-κB and AP-1 expression. Pretreatment with isorhamnetin significantly reduced apoptosis in TNF-α-treated HUVECs. Moreover, isorhamnetin significantly attenuated TNF-α-induced upregulation of ICAM-1, VCAM-1, AP-1, E-selectin and NF-κB expression. Meanwhile, isorhamnetin also increased the expression of eNOS. So, isorhamnetin could suppress TNF-α-induced apoptosis and inflammation by blocking NF-κB and AP-1 signaling in HUVECs, which might be one of the underlying mechanisms for treatment of coronary heart disease.     

The endoplasmic reticulum stress inducer thapsigargin enhances the toxicity of ZnO nanoparticles to macrophages and macrophage-endothelial co-culture

It was recently shown that exposure to ZnO nanoparticles (NPs) could induce endoplasmic reticulum (ER) stress both in vivo and in vitro, but the role of ER stress in ZnO NP induced toxicity remains unclear. Because macrophages are sensitive to ER stress, we hypothesized that stressing macrophages with ER stress inducer could enhance the toxicity of ZnO NPs. In this study, the effects of ER stress inducer thapsigargin (TG) on the toxicity of ZnO NPs to THP-1 macrophages were investigated. The results showed that TG enhanced ZnO NP induced cytotoxicity as revealed by water soluble tetrazolium-1 (WST-1) and neutral red uptake assays, but not lactate dehydrogenase (LDH) assay. ZnO NPs dose-dependently enhanced the accumulation of intracellular Zn ions without the induction of reactive oxygen species (ROS), and the presence of TG did not significantly affect these effects. In the co-culture, exposure of THP-1 macrophages in the upper chamber to ZnO NPs and TG significantly reduced the viability of human umbilical vein endothelial cells (HUVECs) in the lower chamber, but the release of tumor necrosis factor α (TNFα) was not induced. In summary, our data showed that stressing THP-1 macrophages with TG enhanced the cytotoxicity of ZnO NPs to macrophages and macrophage-endothelial co-cultures.     

Comparison of P25 and nanobelts on Kruppel-like factor-mediated nitric oxide pathways in human umbilical vein endothelial cells

Recently, we reported that titanium dioxide (TiO₂) materials activated endothelial cells via Kruppel-like factor (KLF)-mediated nitric oxide (NO) dysfunction, but the roles of physical properties of materials are not clear. In this study, we prepared nanobelts from P25 particles and compared their adverse effects to human umbilical vein endothelial cells (HUVECs). TiO₂ nanobelts had belt-like morphology but comparable surface areas as P25 particles. When applied to HUVECs, P25 particles or nanobelts did not induce cytotoxicity, although nanobelts were much more effective to increase intracellular Ti element concentrations compared the same amounts of P25 particles. Only nanobelts significantly induced THP-1 adhesion onto HUVECs. Consistently, nanobelts were more significant to induce the expression of intracellular adhesion molecule-1 (ICAM1) and the release of soluble ICAM-1 (sICAM-1), indicating that nanobelts were more potent to induce endothelial activation in vitro. As the mechanisms for endothelial activation, both P25 and nanobelts reduced the generation of intracellular NO as well as the expression of NO regulators KLF2 and KLF4. Combined, the results from this study indicated that the different morphologies of P25 particles and nanobelts only changed their internalization into HUVECs but showed minimal impact on KLF-mediated NO signaling pathways.     

Oridonin exhibits anti-angiogenic activity in human umbilical vein endothelial cells by inhibiting VEGF-induced VEGFR-2 signaling pathway

Oridonin has been found to be a potential anti-angiogenesis agent. However, its functional targets and the underlying mechanisms are still vague. In vitro studies we found that oridonin not only inhibited VEGF-induced cell proliferation, migration and tube formation but also caused G2/M phase arrest and triggered cellular apoptosis in HUVECs. In mechanistic studies revealed that oridonin exhibited the anti-angiogenic potency, at least in part, through the down-regulation of VEGFR2-mediated FAK/MMPs, mTOR/PI3K/Akt and ERK/p38 signaling pathways which led to reduced invasion, migration, and tube formation in HUVECs. Our results could provide evidence that oridonin exerts strong anti-angiogenesis activities via specifically targeting VEGFR2 and its signaling pathway.     

丙酮酸乙酯对人脐静脉内皮细胞HMGB1表达的影响

目的：本研究意在探讨丙酮酸乙酯（EP）对炎症因子HMGB1表达的影响,从而证实EP在急性脓毒症中的作用及机制。方法：采用原代培养的人脐静脉内皮细胞（HUVECs）,免疫组化法鉴定其纯度,台盼蓝拒染实验鉴定细胞活力。观察不同计量的EP对人脐静脉内皮细胞分泌HMGB1的作用。细胞分三组：LPS 100 ng/mL＋EP 0μM组、LPS 100 ng/mL＋EP 5μM组、LPS 100 ng/mL＋EP 10μM组。采用Western blot方法检测培养上清液HMGB1的含量。结果：各细胞组于LPS 100 ng/mL刺激16 h后,EP 5μM剂量组对HMGB1分泌具有一定的抑制作用,与EP 0μM组比,HMGB1含量明显降低（t=21.27,P〈0.05）;10μM剂量组与0μM组比,降低HMGB1作用更为明显（t=26.38,P〈0.05）。结论：丙酮酸乙酯可以减少血管内皮细胞释放HMGB1,对急性脓毒症有改善作用。     

Senescence Affects Endothelial Cells Susceptibility to Dengue Virus Infection

Alteration in the endothelium leading to increased vascular permeability contributes to plasma leakage seen in dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). An earlier study showed that senescent endothelial cells (ECs) altered the ECs permeability. Here we investigated the susceptibility of senescing human umbilical vein endothelial cells (HUVECs) to dengue virus infection and determined if dengue virus infection induces HUVECs senescence. Our results suggest that DENV type-2 (DENV-2) foci forming unit (FFU) and extracellular virus RNA copy number were reduced by at least 35% and 85% in infection of the intermediate young and early senescent HUVECs, respectively, in comparison to infection of young HUVECs. No to low infectivity was recovered from infection of late senescent HUVECs. DENV infection also increases the percentage of HUVECs expressing senescence-associated (SA)-β-gal, cells arrested at the G2/M phase or 4N DNA content stage and cells with enlarged morphology, indicative of senescing cells. Alteration of HUVECs morphology was recorded using impedance-based real-time cell analysis system following DENV-2 infection. These results suggest that senescing HUVECs do not support DENV infection and DENV infection induces HUVECs senescence. The finding highlights the possible role of induction of senescence in DENV infection of the endothelial cells.