白花丹参对过氧化氢致人脐静脉血管内皮细胞损伤的保护作用

目的研究白花丹参对过氧化氢（H2O2）所致人脐静脉血管内皮细胞（HUVEC）损失的保护作用。方法应用酶消化灌注法培养人脐静脉血管内皮细胞,采用形态学观察和Ⅷ因子抗体免疫荧光检测法进行鉴定;取对数生长期的细胞分组进行干预,应用形态学观察法和MTT法检测各组血管内皮细胞的活性。结果H2O2损伤模型组细胞损伤明显,经白花丹参高、中、低各剂量组的干预,受损情况均有较明显地改善,使细胞活性（OD值）增高。结论白花丹参对H2O2所致的HUVEC损伤具有保护作用。     

NB-UVB辐射对HUVEC分泌sE-selectin及sICAM-1的影响

目的研究NB-UVB辐射对TNF-α刺激人脐静脉血管内皮细胞(HUVEC)表达可溶性E选择素(sE-se-lectin)及可溶性细胞间黏附分子(sICAM-1)的影响。方法体外培养人脐静脉血管内皮细胞(HU-VEC),将HUVEC接种于96孔塑料培养板,分为对照组,TNF-α组,TNF-α+NB-UVB60mJ/cm2剂量组,TNF-α+NB-UVB40mJ/cm2剂量组,TNF-α+NB-UVB20mJ/cm2剂量组。TNF-α刺激浓度为10ng/mL;NB-UVB高,中,低剂量组剂量分别为20,40,60mJ/cm2。采集上清,ELISA法检测可溶性E选择素(sE-selectin)和可溶性细胞间黏附分子1(sICAM-1)含量。结果 NB-UVB能剂量依赖性地抑制TNF-α刺激后HUVEC分泌sE-selectin和sICAM-1。结论 NB-UVB可能通过抑制血管内皮细胞表达黏附分子在治疗炎症性皮肤病中发挥免疫调节作用。     

Bio-Effects of TiO2 Nanoparticles on Human Colorectal Cancer and Umbilical Vein Endothelial Cell Lines

Background: Due to the possible biomedical potential of nanoparticles, titanium dioxide nanoparticles (TiO2 NPs)have received great attention in cancer research. Although selectivity of cytotoxicity with TiO2 NPs in various cells isclinically significant comparisons of cancer and non-cancer cells have been limited. Therefore, we here studied exposureto TiO2 NPs in colorectal cancer cells (CRCs) and human umbilical vein endothelial cells (HUVECs). Methods: Aftercharacterization of TiO2 NPs, culture and treatment of cells (HCT116, HT29 and HUVEC), viability was assessed byMTT assay and in terms of morphological features. Acridine orange (AO) and propidium iodide (PI) assays were carriedout to estimate the incidence of apoptosis. The RT-PCR method was also employed to evaluate the expression of P53,Bax, Bcl-2 and Caspase 3. Results: Exposure to increasing concentrations of TiO2 NPs enhanced overall cell survivalof HCT116 cells and reduced the Bcl-2 and Caspase 3 expression while the ratio of Bax/Bcl-2 was down-regulated.TiO2 NPs at 400 and 50 μg/ml concentrations suppressed cell proliferation and induced apoptosis of HT29 cells andalso up-regulated P53 and Bax at the mRNA level, enhanced the Bax/Bcl-2 ratio and eventually up-regulated Caspase3 mRNA. Although, inhibition of cell proliferation in HUVECs was seen at 200 and 400 μg/ml TiO2 NPs, it was notmarked. Conclusion: TiO2 NPs have selective bio-effects on exposed cells with dose- and cell-dependent influence onviability. Cell proliferation in HCT116 as a metastatic colorectal cancer cell line appeared to be stimulated via multiplesignaling pathways, with promotion of apoptosis in less metastatic cells at 50 and 400 μg/ml concentrations. This wasassociated with elevated P53, Bax and Caspase 3 mRNA and reduced Bcl-2 expression. However, TiO2 NPs did notexert any apparent significant effects on HUVECs as hyperproliferative angiogenic cells.     

Comparative study of adhesion molecule expression in cultured human macro- and microvascular endothelial cells

Culture systems as models for disease are only valid as long as they are comparable to in vivo conditions. The phenotype of cultured endothelial cells (ECs) has only been sporadically compared to the corresponding phenotype in vivo. Thus, we compared by immunolocalization the endothelial expression of ICAM-1, VCAM, and E-selectin in vivo in stimulated/unstimulated human umbilical vein endothelial cells (HUVEC) as a model for macrovascular ECs and stimulated/unstimulated HPMEC (human pulmonary microvessel endothelial cells) as a model for pulmonary microvascular ECs with that in human lungs in vivo (normal and ARDS). Proinflammatory stimuli in vitro were used to stimulate conditions relevant for ARDS. ICAM-1 expression in stimulated HUVEC/HPMEC correlated well with in vivo expression (macro- and microvessels). For E-selectin, the staining pattern in macro/microvessels correlated moderately with unstimulated and well with stimulated HUVEC/HPMEC. For VCAM a good correlation was found for stimulated/unstimulated HUVEC and unstimulated HPMEC. The expression patterns in stimulated HUVEC corresponded well for all three molecules with those in vivo. Thus, the expression patterns in vitro are only partially transferable to in vivo conditions. The study suggests that E-selectin- and VCAM-coated beads could potentially serve in the isolation process of arteriolar and venular ECs.     

风湿祛痛胶囊对VEGF诱导的人脐静脉内皮细胞功能的影响

目的:观察风湿祛痛胶囊对血管内皮细胞生长因子(VEGF)诱导的人脐静脉内皮细胞(HUVEC)的增殖、迁移、黏附、侵袭和管腔形成能力的影响,以及对VEGF受体2(VEGFR2)的干预作用。方法:VEGF体外诱导HUVEC,加入风湿祛痛胶囊低、中、高质量浓度(0. 02,0. 1,0. 5μg·L-1)作用后,分别采用噻唑蓝(MTT)比色法、转移小室(transwell)法、黏附实验、细胞侵袭及管腔形成实验检测HUVEC的增殖活性、迁移、黏附、侵袭及管腔形成能力,蛋白免疫印迹法(Western blot)检测细胞中VEGFR2磷酸化水平和蛋白含量,实时荧光定量聚合酶链式反应(Real-time PCR)检测VEGFR2 mRNA表达水平。结果:与正常组比较,VEGF诱导24,48 h后均能显著升高HUVEC的增殖活性(P 0. 01),诱导24 h能明显升高HUVEC的迁移、黏附、侵袭和管腔形成能力(P 0. 01),显著升高HUVEC中VEGFR2磷酸化及蛋白和mRNA表达水平(P 0. 01);与VEGF组比较,风湿祛痛胶囊低、中、高质量浓度组作用48 h均能明显抑制HUVEC增殖活性(P 0. 05,P 0. 01),作用24 h对VEGF诱导的HUVEC迁移、黏附、侵袭和管腔形成能力有明显抑制作用(P 0. 05),也能下调VEGFR2磷酸化及蛋白和mRNA表达水平(P 0. 05)。结论:风湿祛痛胶囊能降低VEGF诱导的HUVEC细胞增殖、迁移、黏附、侵袭及管腔形成能力,这一作用可能与其抑制VEGFR2的磷酸化、蛋白和mRNA表达水平有关。     

Cyclo(dehydrohistidyl-l-tryptophyl) inhibits nitric oxide production by preventing the dimerization of inducible nitric oxide synthase

Dimerization of inducible NOS has been known to be a potential therapeutic target for iNOS-mediated pathologies. Cyclic dipeptides are among the simplest peptides commonly found as by-products of food processing or metabolites of microorganisms. In this study, we found that cyclo(dehydrohistidyl-l-tryptophyl) (CDHT), a cyclic dipeptide from an unidentified fungal strain Fb956, prevents iNOS dimerization in activated microglial BV-2 cells. CDHT inhibited NO production with an IC50 of 6.5 microM in LPS-treated BV-2 cells. Western blot analysis and iNOS activity measurement of fractions from size-exclusion chromatography of cell lysates indicated that CDHT inhibits dimerization of iNOS, while it has no effect on iNOS expression or enzyme activity. The CDHT inhibition of iNOS dimerization was confirmed by partially denaturing SDS-PAGE analysis. In contrast, CDHT did not affect cGMP production in endothelial HUVEC cells, which indicates no inhibition of endothelial NOS activity. These results reveal that CDHT, one of the simplest and cyclic dipeptides, selectively inhibits NO production by inhibiting iNOS dimerization, and could be a useful therapeutic agent for inflammation-mediated diseases.     

Celecoxib modulates adhesion of HT29 colon cancer cells to vascular endothelial cells by inhibiting ICAM-1 and VCAM-1 expression

BACKGROUND AND PURPOSE: Cyclooxygenase-2 (COX-2) is highly expressed during inflammation and can promote the progression of colorectal cancer. Interactions between cancer cells and vascular endothelial cells are key events in this process. Recently, the selective COX-2 inhibitor, celecoxib, was shown to inhibit expression of the adhesion molecules, ICAM-1 and VCAM-1, in the human colon cancer cell line HT29 and to inhibit adhesion of HT29 cells to FCS-coated plastic wells. Here, we evaluated the effects of celecoxib on adhesion of HT29 cells to human umbilical vein endothelial cells (HUVEC), mediated by ICAM-1 and VCAM-1, to assess further the potential protective effects of celecoxib on cancer development. EXPERIMENTAL APPROACH: Celecoxib was incubated for 4 h with HT29 cells and HUVEC and adhesion was quantified by a computerized micro-imaging system. Expression analysis of ICAM-1 and VCAM-1 cell adhesion molecules was performed by western blot. KEY RESULTS: Celecoxib (1 nM-10 microM) inhibited, with the same potency, adhesion of HT29 cells to resting HUVEC or to HUVEC stimulated by tumour necrosis factor-alpha (TNF-alpha), mimicking inflammatory conditions. Analysis of ICAM-1 and VCAM-1 expression showed that celecoxib inhibited expression of both molecules in TNF-alpha-stimulated HUVEC, but not in resting HUVEC; inhibition was concentration-dependent and maximal (about 50%) at 10 microM celecoxib. CONCLUSIONS AND IMPLICATIONS: In conclusion, our data show that celecoxib inhibits HT29 cell adhesion to HUVEC and expression of ICAM-1 and VCAM-1, in stimulated endothelial cells. These effects may contribute to the chemopreventive activity of celecoxib in the development of colorectal cancer.     

rTNF_(-α)、IFN_(γ)对人脐静脉内皮细胞表达粘附分子的影响

为了研究细胞因子ｒＴＮＦ α、ＩＦＮγ对内皮细胞表达粘附分子的影响,及ｒＩＦＮγ对ＴＮＦ α的协同效应。采用ｒＴＮＦ α、ＩＦＮγ诱导培养的人脐静脉内皮细胞（ＨＵＶＥＣ）,以Ｃｅｌ ＥＬＩＳＡ法检测粘附分子ＩＣＡＭ １、ＥＬＡＭ １和ＶＣＡＭ １的表达。结果表明,ｒＴＮＦ α以浓度和时间依赖的方式诱导ＨＵＶＥＣ表达ＩＣＡＭ １、ＥＬＡＭ １和ＶＣＡＭ １,ＩＦＮγ促进ｒＴＮＦ α诱导的ＶＣＡＭ １表达。ＩＦＮ α对ｒＴＮＦ α诱导效应无影响。提示ｒＴＮＦ α可诱导ＨＵＶＥＣ表达粘附分子,而ＩＦＮγ可促进ｒＴＮＦ α诱导的ＨＵＶＥＣ表达ＶＣＡＭ １。     

Cytoprotective role of astaxanthin against glycated protein/iron chelate‐induced toxicity in human umbilical vein endothelial cells

Astaxanthin (ASX), a red carotenoid pigment with no pro‐vitamin A activity, is a biological antioxidant that occurs naturally in a wide variety of plants, algae and seafoods. This study investigated whether ASX could inhibit glycated protein/iron chelate‐induced toxicity in human umbilical‐vein endothelial cells (HUVEC) by interfering with ROS generation in these cells. Glycated fetal bovine serum (GFBS) was prepared by incubating fetal bovine serum (FBS) with high‐concentration glucose. Stimulation of cultured HUVECs with 50 mm 1 mL of GFBS significantly enhanced lipid peroxidation and decreased antioxidant enzyme activities and levels of phase II enzymes. However, preincubation of the cultures with ASX resulted in a marked decrease in the level of lipid peroxide (LPO) and an increase in the levels of antioxidant enzymes in an ASX concentration‐dependent manner. These results demonstrate that ASX could inhibit LPO formation and enhance the antioxidant enzyme status in GFBS/iron chelate‐exposed endothelial cells by suppressing ROS generation, thereby limiting the effects of the AGE–RAGE interaction. The results indicate that ASX could have a beneficial role against glycated protein/iron chelate‐induced toxicity by preventing lipid and protein oxidation and increasing the activity of antioxidant enzymes. Copyright © 2009 John Wiley & Sons, Ltd.