Effects of C5a and FMLP on Interleukin-8 Production and Proliferation of Human Umbilical Vein Endothelial Cells

Interleukin-8 (IL-8), C5a and N-formyl-methionyl-leucyl-phenylalanine (fMLP) are chemotactic peptides with predominant effects on leukocytes during inflammation. With emphasis on C5a we studied the regulation of the production of IL-8 by human umbilical vein endothelial cells (HUVEC) in vitro. Primary HUVEC cultures were incubated with IL-1, TNF, C5a and fMLP for 24 h and 48 h prior to measurement of IL-8 in supernatants of the cells by an enzyme immunoassay. Whereas IL-1 and TNF significantly increased the levels of IL-8, C5a decreased the IL-8 production after 48 h. In addition, the ability of IL-1, TNF, C5a, fMLP and IL-8 to induce cell proliferation was compared by means of a ³H-thymidine incorporation assay. In contrast with IL-1 and TNF, both C5a and fMLP increased cell proliferation of HUVEC. This increase occurred with increasing concentrations of C5a contrary to IL-8, which showed increased cell proliferation at low, but not high IL-8 concentrations.     

小陷胸汤加味含药血清对人脐静脉内皮细胞分泌NO/ET-1的调节作用

目的:探讨小陷胸汤加味中药方对血管内皮细胞的保护作用。方港:建立ox-LDL损伤人脐静脉内皮细胞株(ECV-304)模型,用小陷胸汤加味含药血清处理模型,并用放免和硝酸酶还原法在药物干预6h和24h后检测细胞上清液中ET-1和NO含量。结果:100 μg/ml的ox-LDL可损伤血管内皮细胞并导致其分泌NO和ET-1功能失调,小陷胸汤加味含药血清通过影响NO/ET-1的分泌而明显改善此失调状态。结论:小陷胸汤加味中药通过调节NO/ET-1水平显著拮抗ox-LDL对血管内皮细胞损害,具有防治AS的作用。     

A novel metalloprotease from Vipera lebetina venom induces human endothelial cell apoptosis.

A novel endothelial cell apoptosis inducing metalloprotease (VLAIP) was found in the snake venom of Vipera lebetina. This metalloprotease is a heterodimeric glycoprotein with molecular mass of about 106 kDa. The protease hydrolyzes azocasein, fibrinogen and oxidized insulin B-chain. The enzyme readily hydrolyzes the Aalpha-chain and more slowly Bbeta-chain of fibrinogen. VLAIP does not cleave fibrin. The complete amino acid sequences of the two different monomers of VLAIP are deduced from the nucleotide sequences of cDNAs encoding these proteins. The full-length cDNA sequences of the VLAIP-A and VLAIP-B encode open reading frames of 616 and 614 amino acids that include signal peptide, propeptide and mature metalloproteinase with disintegrin-like and cysteine-rich domains. VLAIP belongs to the metalloprotease/disintegrin family of reprolysins and has high identity with the proteins that induce apoptosis of endothelial cells. Treatment of HUVEC cells with VLAIP induces changes in the attachment of cells to the substrate and causes cell death. We demonstrated that VLAIP inhibits endothelial cell adhesion to extracellular matrix proteins: fibrinogen, fibronectin, vitronectin, collagen I, and collagen IV. The induction of apoptosis by VLAIP was shown by means of a typical DNA fragmentation pattern of apoptotic cells as well as by monitoring phosphatidylserine externalization using annexin V-FITC staining and flow cytometric analysis.     

A Novel Peptide from Polypedates megacephalus Promotes Wound Healing in Mice

Amphibian skin contains wound-healing peptides, antimicrobial peptides, and insulin-releasing peptides, which give their skin a strong regeneration ability to adapt to a complex and harsh living environment. In the current research, a novel wound-healing promoting peptide, PM-7, was identified from the skin secretions of Polypedates megacephalus, which has an amino acid sequence of FLNWRRILFLKVVR and shares no structural similarity with any peptides described before. It displays the activity of promoting wound healing in mice. Moreover, PM-7 exhibits the function of enhancing proliferation and migration in HUVEC and HSF cells by affecting the MAPK signaling pathway. Considering its favorable traits as a novel peptide that significantly promotes wound healing, PM-7 can be a potential candidate in the development of novel wound-repairing drugs.     

愈肾汤总黄酮的成分组成和活性研究

目的:对愈肾汤总黄酮的化学成分和活性进行研究,为处方的活性成分揭示和作用机制阐明奠定基础.方法:采用体外H2O2诱导人脐静脉内皮细胞(HUVEC)损伤实验评价愈肾汤总黄酮的活性.并采用硅胶柱、大孔吸附树脂、葡聚糖凝胶色谱和高效液相制备等方法分离纯化愈肾汤总黄酮的化学成分,根据理化性质和波谱数据鉴定其结构.结果:愈肾汤总黄酮具有明显的抗过氧化氢诱导的HUVEC损伤和下调PAI-1表达(P＜0.05)的作用.从愈肾汤总黄酮部位分离得到9个黄酮类化合物分别为毛蕊异黄酮(1)、蒙花苷(2)、3',4'-二羟基-7-O-β-D-葡萄糖苷(3)、3'-羟基-4'-甲氧基-7-O-β-D-葡萄糖苷(4)、槲皮素(5)、山柰酚(6)、芦丁(7)、红车轴草异黄酮-7-O-β-D-葡萄糖苷(8)、4'-羟基二氢黄酮-7-O-β-D-葡萄糖苷(9).结论:愈肾汤总黄酮具有抗HUVEC氧化损伤作用,所分离的9个黄酮化合物均为首次从该方中分离得到,化合物1,3,4,8,9可能来自于黄芪,化合物2,5～7可能来自于小蓟和仙鹤草,其中3,4和9为首次从组方的单味药中分离得到.     

冠心病不同阶段患者血清对人脐静脉血管内皮细胞促增殖作用的实验研究

目的观察冠心病不同阶段患者血清对人脐静脉血管内皮细胞（HUVEC）增殖的影响。方法采集正常健康人群（正常组）、冠心病中高危人群（中高危组）、冠心病急性期患者（急性期组）、冠心病稳定期患者（稳定期组）的血清,分别作用于HUVEC,培养至24、48、72、96h检测吸光度值（OD值）。结果4组血清中加或不加5％胎牛血清,其对HUVEC增殖均有促进作用,正常组、中高危组、急性期组、稳定期组对HUVEC的促增殖作用呈逐渐增强趋势,稳定期组血清促增殖作用最强。结论心血管疾病在急性期后,随着病程和生存期的延长,其血清对HUVEC的促增殖作用逐渐增强。     

柚皮素对ARPE-19和HUVEC细胞的抗氧化作用

目的：研究柚皮素对人视网膜色素上皮细胞（ARPE-19）和人脐静脉内皮细胞（HUVEC）的抗氧化作用。 方法：采用MTT的方法检测ARPE-19和HUVEC细胞的生存率及增殖率。 结果：3，10mg／L柚皮素能显著增加ARPE-19细胞的增殖率达10．8％和11．4％。10mg／L柚皮素能提高ARPE-19细胞在缺氧，0．3mmol／LNaN，及200μmol／L，H2O2条件下的生存率分别为55．2％，69．2％及50．3％。1mg／L柚皮素能提高ARPE-19细胞在50μmol／L t-BHP和30mg／LNaIO3条件下的生存率达20．2％和30．4％。30mg／L柚皮素能够促进ARPE-19细胞在50μmol／L t-BHP条件下的增殖率达32．2％，而1mg／L柚皮素可以提高30，100，300mg／LNaIO3处理的ARPE-19细胞的增殖率达30．3％，10．3％及18．5％。3，10及30mg／L柚皮素抑制HUVEC的增殖率分别为23．9％，70．4％及77．9％。1，3mg／L柚皮素能提高HUVEC细胞在缺氧条件下的生存率达10．7％和13．1％，以及提高在300mg／LNaIO3条件下的生存率达41．2％和37．7％。3mg／L柚皮素能提高HUVEC细胞在200，400μmol／L H2O2条件下的生存率达20．1％和21．5％． 结论：柚皮素能够促进ARPE-19细胞的增殖率，抑制HU-VEC生长，同时对这两种细胞均有抗氧化作用。因此，柚臾素是治疗老年黄斑变性的很有前景的候选药物。     

Cyclopeptide RA-V inhibits angiogenesis by down-regulating ERK1/2 phosphorylation in HUVEC and HMEC-1 endothelial cells

BACKGROUND AND PURPOSE

Anti-angiogenic agents have recently become one of the major adjuvants for cancer therapy. A cyclopeptide, RA-V, has been shown to have anti-tumour activities. Its in vitro anti-angiogenic activities were evaluated in the present study, and the underlying mechanisms were also assessed.

EXPERIMENTAL APPROACH

Two endothelial cell lines, human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC-1), were used. The effects of RA-V on the proliferation, cell cycle phase distribution, migration, tube formation and adhesion were assessed. Western blots and real-time PCR were employed to examine the protein and mRNA expression of relevant molecules.

KEY RESULTS

RA-V inhibited HUVEC and HMEC-1 proliferation dose-dependently with IC₅₀ values of 1.42 and 4.0 nM respectively. RA-V inhibited migration and tube formation of endothelial cells as well as adhesion to extracellular matrix proteins. RA-V treatment down-regulated the protein and mRNA expression of matrix metalloproteinase-2. Regarding intracellular signal transduction, RA-V interfered with the activation of ERK1/2 in both cell lines. Furthermore, RA-V significantly decreased the phosphorylation of JNK in HUVEC whereas, in HMEC-1, p38 MAPK was decreased.

CONCLUSIONS AND IMPLICATIONS

RA-V exhibited anti-angiogenic activities in HUVEC and HMEC-1 cell lines with changes in function of these endothelial cells. The underlying mechanisms of action involved the ERK1/2 signalling pathway. However, RA-V may regulate different signalling pathways in different endothelial cells. These findings suggest that RA-V has the potential to be further developed as an anti-angiogenic agent.     

霉酚酸对趋化性细胞因子I-TAC的表达及其功能的影响

研究探讨霉酚酸(MPA)对趋化性细胞因子I-TAC的表达及其功能的影响。分别在IFN-γ加入之前、同时、之后加MPA于培养的ECV-304细胞中,以RT-PCR检测其I-TAC mRNA的表达水平。PBMC经不同浓度MPA(10、100、1 000ng/ml)处理12 h后,采用微迁移板技术观察MPA对I-TAC趋化作用的影响。MTT法测定不同浓度MPA(10、100、1 000ng/ml)对I-TAC促PBMC增殖效应的影响。结果显示,在不同时间加入MPA处理的各组,其I-TAC/GAPDH比值均显著地小于对照组(P<0.01),而MPA处理组之间无显著性差异(P>0.05)。MPA处理组PBMC的迁移指数和MTT试验的A值与相应对照组相比均显著下降(P<0.05)。这些结果提示,MPA对I-TAC在内皮细胞上表达及其趋化、促增殖功能具有抑制作用。MPA的这些新发现的功能可能是霉酚酸酯(MMF)抗移植排斥的重要机制之一。     

麝香酮对氧化应激损伤人血管内皮细胞凋亡的影响

目的:观察麝香酮对过氧化氢(H2O2)诱导人血管内皮细胞(HUVEC)凋亡的保护效应,并探讨其作用机制。方法:运用H2O2建立血管内皮细胞凋亡模型,继而用低、中、高不同剂量的麝香酮进行干预,并用MTT法检测细胞增殖,Hoechst 33258荧光染色及流式细胞技术检测细胞凋亡,激光共聚焦显微镜测定Ca2+浓度和线粒体膜电位(ΔΨm)的变化。结果:H2O2诱导HUVEC细胞凋亡,中、高剂量的麝香酮对HUVEC细胞增殖均有明显促进作用;H2O2组与正常组相比ΔΨm显著下降,Ca2+浓度明显升高(P<0.01);中、高剂量组与H2O2组相比ΔΨm则显著升高,Ca2+浓度明显降低(P<0.01)。结论:麝香酮可通过稳定线粒体ΔΨm,减轻细胞通透性,减少Ca2+内流,从而抑制H2O2所致的HUVEC细胞凋亡。