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1.
雷公藤内酯抑制内皮细胞血管内皮生长因子表达与合成   总被引:11,自引:0,他引:11  
目的:研究雷公藤内酯对血管内皮细胞生长因子(VEGF)mRNA表达及VEGF合成与分泌的影响,进一步探讨雷公藤内酯降低肾小球肾炎患者尿蛋白的作用机制。方法:以人内皮细胞系ECV-304为研究对象,利用半定量逆转录聚合酶链反应(RT-PCR),流式细胞仪,酶联免疫吸附法(ELISA)检测不同剂量雷公藤内酯对佛波脂(TPA)诱导的内皮细胞VEGFmRNA表达及VEGF合成与分泌的影响,用RT-PCR检测雷公藤内酯对内皮细胞c-fos/c-jun mRNA表达的影响。结果:TPA能够明显上调VEGF mRNA表达,蛋白合成与分泌。而雷公藤内酯可以抑制TPA诱导的内皮细胞VEGF mRNA表达及VEGF蛋白合成与分泌,该作用在10μg·L~(-1)时更为明显。同样,雷公藤内酯剂量依赖性地抑制TPA诱导的内皮细胞c-fos/c-jun mRNA的表达。结论:雷公藤内酯通过影响c-fos/c-jun基因转录而抑制内皮细胞VEGFmRNA表达及VEGF合成与分泌是雷公藤内酯降低肾小球肾炎患者尿蛋白的作用机制之一。  相似文献   

2.
Zhou HJ  Wang WQ  Wu GD  Lee J  Li A 《Vascular pharmacology》2007,47(2-3):131-138
Artesunate (ART), a semi-synthetic derivative of artemisinin extracted from the Chinese herb Artemisia annua, is a safe and effective antimalarial drug. In the present investigation, we analyzed the inhibitory effects of ART on angiogenesis and on VEGF production in chronic myeloid leukemia (CML) K562 cells in vitro and in vivo. In order to analyze the effect of ART on VEGF secretion in K562 cells, we examined the level of VEGF secreted in conditioned media (CM) by ELISA assay. The result showed that ART could decrease the VEGF level in CM of K562 cells, even at a lower concentration (2 micromol/l, P<0.01). The inhibitory effect of in vitro angiogenesis was tested on aortic sprouting in fibrin gel. ART could effectively suppress the stimulating angiogenic ability of CM by pretreated with K562 cells for 48 h in a time-dependent manner (days 3-14). The antiangiogenic effect of ART was further evaluated in vivo in chicken chorioallantoic membrane (CAM) neovascularization model. The result indicated that the stimulating angiogenic activity was decreased in response to the K562 cells treated with ART or the CM from K562 cells pretreated with ART in a dose-dependent manner (3-12 micromol/l). Furthermore, we analyzed the level of VEGF expression by western blot and detected the form of VEGF mRNA by RT-PCR in K562 cells. The experiments showed that ART could inhibit the VEGF expression, correlated well with the level of VEGF secreted in CM. These findings suggest that ART might present potential antileukemia effect as a treatment for CML therapy, or as an adjunct to standard chemotherapeutic regimens.  相似文献   

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Vascular Endothelial Growth Factor (VEGF) plays a crucial role in the establishment of the vascular tree pattern. New vessels can be formed by two different ways; in the development of kidney both vasculogenesis and angiogenesis participate to microvessel assembly. VEGF and its receptor (VEGF-R) are co-expressed during kidney organogenesis and stimulate renal blood vessels development, induce and maintain the fenestrated phenotype in endothelium and regulate vascular permeability. VEGF and many other growth factors participate to the development of embryonic glomerular microvasculature. We believe that therapeutical use of VEGF or anti-VEGF antibodies may be performed in the treatment of many disorders.  相似文献   

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目的研究氧诱导视网膜新生血管小鼠模型中视网膜血管内皮细胞生长因子(VEGF)与视网膜新生血管的相关性。方法通过建立氧诱导视网膜新生血管小鼠模型,分别于12、14、17、21 d龄随机抽取2组幼鼠各6只,一侧眼球测定视网膜VEGF水平,另一侧眼球进行视网膜铺片、ADP酶染色,考察其相关性。结果模型组小鼠左眼球ADP酶染色结果显示,模型组12 d龄小鼠血管迂曲、扩张、变形,随时间延长血管变形加重,17 d时最严重,且视乳头周围出现大片无灌注区,视网膜周边可见大量新生血管生成,到21 d时模型开始恢复。视网膜VEGF测定结果显示,12 d龄模型小鼠VEGF开始升高,17 d达峰值,以后下降。结论视网膜VEGF变化和视网膜血管形态具有很好的正相关性,17 d时新生血管形成最多。  相似文献   

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目的:了解反义VEGF寡脱氧核苷酸(ODN)对人胶质细胞瘤系(A172细胞)VEGF表达的抑制作用。方法:应用半定量PCR、免疫组化方法分别了解细胞内VEGF mRNA和蛋白的变化,并利用ELISA检测培养上清液中VEGF蛋白的含量。结果:A172细胞经反义VEGF ODN作用后VEGF mRNA的表达量明显减少,且随其浓度的增加而明显减少,但其表达量不受正义和错义VEGF ODN的影响。当A172细胞经50μmol·L~(-1)反义VEGF ODN作用后,细胞内及上清液内VEGF蛋白水平较对照显著减少。结论:反义VEGF ODN特异地抑制A172细胞VEGF mRNA和蛋白的表达。  相似文献   

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To address the role of prostaglandin E2 (PGE2) in tube formation of endothelial cells and the relationships between the action of PGE2 and vascular endothelial growth factor (VEGF), cultured human umbilical vein endothelial cells (HUVECs) were used to evaluate tube formation on Matrigel and the expression of angiogenesis-related genes. PGE2 treatment stimulated the tube-like formation of HUVECs. Whereas VEGF-induced tube formation was significantly suppressed by ETYA, an inhibitor of arachidonic acid metabolism, or SU5614, an inhibitor of VEGF-receptor tyrosine kinase, the stimulatory effect of PGE2 was observed in the presence of ETYA or SU5614. Thus, PGE2 counteracted both ETYA- and SU5614-induced blockage of angiogenesis in the presence of VEGF. VEGF induced cyclooxygenase (COX) -2 mRNA expression in HUVECs and increased the PGE2 concentration in the medium. PGE2 treatment enhanced the expression of VEGF mRNA. These findings suggest that PGE2 directly stimulates angiogenesis, apart from VEGF signaling, and further induces VEGF expression in HUVECs. In addition, the effect of VEGF on angiogenesis may be mediated, in part, by PGE2 secretion.  相似文献   

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Vascular endothelial growth factor (VEGF) is a key factor in angiogenesis and vascular permeability which is associated with many pathological processes. 2,5-hydroxybenzene sulfonate (DHBS; dobesilate) is a small molecule with anti-angiogenic activity that has been described as an inhibitor of fibroblast growth factors (FGF). The aim of the present study was to evaluate the effects of DHBS on VEGF-induced actions. The effects of DHBS were evaluated on VEGF-induced proliferation in human umbilical vein endothelial cells (HUVEC) and rat aorta relaxation, as well as on in vivo VEGF-induced skin vascular permeability and neovascularization in rats. DHBS at 50 and 100 μM concentration significantly inhibited the proliferation of HUVEC induced by VEGF (10 ng/ml), without significantly affecting HUVEC proliferation in the absence of VEGF. Rapid VEGF-induced activation of Akt in HUVEC was also prevented by DHBS (100 μM). Additionally, DHBS (2 μM) specifically inhibited the relaxation of rat aorta induced by VEGF (0.1 to 30 ng/ml), but not endothelium-dependent relaxation to acetylcholine (1 nM to 10 μM). The in vivo enhancement of vascular permeability caused by VEGF injection (50 μl at 10 ng/ml) in rat skin was also inhibited by DHBS co-administration (200 μM) (74.8±3.8% inhibition of dye extravasation). Administration of DHBS (200 mg/kg/day; i.p.) also reduced VEGF-induced angiogenesis in vivo. DHBS inhibits main responses elicited in vitro and in vivo by VEGF. As a dual antagonist of VEGF and FGF activities, DHBS could be of therapeutic interest in the treatment of diseases related to VEGF/FGF overproduction and excessive angiogenesis.  相似文献   

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Purpose: To investigate the effect of microRNA-16 on hypoxia-induced VEGF expression of ARPE-19 cells.

Methods: ARPE-19 cells were cultivated under normoxia and hypoxia state. At 0?h, 12?h, 24?h, and 48?h after cultivation, the supernate of the culture medium was separated to test the VEGF secretion by ELISA, and the cells were purified to measure the expression of VEGF mRNA and microRNA-16 by qRT-PCR; microRNA-16 mimic was then transfected into ARPE-19 cells by the Hiperfect transfection reagent, a liposome transfection system. Scramble group and the non-transfected group were set as the controls. VEGF secretion and the level of VEGF mRNA were measured in these three groups.

Results: The VEGF secretion of the hypoxia ARPE cells was significantly higher than the initial state (p?p?p?p?p?Conclusions: Hypoxia can increase the expression of VEGF mRNA and the secretion of VEGF protein of ARPE-19 cells. At the same time, microRNA-16 expression can be down-regulated by hypoxia. Transfection of microRNA-16 exogenously can down-regulate the VEGF protein secretion but cannot affect the expression of VEGF mRNA.  相似文献   

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AIM:To study the expression of vascular endothelial growth factor (VEGF) induced by oxidized low density liprotein (ox-LDL) and the inhibitory effects of antisense oligodeoxynucleotide (asODN) on the levels of VEGF protein and mRNA in the U937 foam cells. METHODS: U937 cells were incubated with ox-LDL 80 mg/L for 48h, then ,the foam cells were treated with asODN (0,5,10, and 20μmol/L). The VEGF concentration in the media was determined by ELISA. The VEGF protein expression level in cells was measured by immuohistochemistry; the positive ratio detected by a morphometrical analysis system was used as the amount of the VEGF expression level. The VEGF mRNA level was examined by Northern blotting. RESULTS: After U937 cells were incubated with ox-LDL, VEGF expression level increased greatly both in the cells and in the media. asODN markeldy inhibited the increase of VEGF. After treatment with asODN 20μmol/L, the VEGF protein concentration in the media decreased by 45.0%, the VEGF positive ratio detected by immuohistochemistry in cells decreased by 64.9%, and the VEGF mRNA level decreased by 47.1%. CONCLUSION: The expression of VEGF in U937 foam cells was strong. asODN inhibited VEGF expression significantly in U937 foam cells in vitro.  相似文献   

13.
二氢青蒿素抑制K562细胞血管内皮生长因子的表达   总被引:15,自引:0,他引:15  
李菌  周慧君 《药学学报》2005,40(11):1041-1045
目的通过观察二氢青蒿素抑制K562细胞血管内皮生长因子(VEGF)的表达,探讨青蒿素类药物在抑制血液肿瘤血管新生方面的作用。方法运用MTT法、免疫组化分析和Western blotting分析等探讨了二氢青蒿素对K562细胞增殖以及VEGF表达方面的影响,并进一步对药物预处理后肿瘤细胞的条件培养基在促内皮细胞增殖以及促鸡胚绒毛尿囊膜(CAM)血管新生的作用进行评定。结果二氢青蒿素能有效抑制K562细胞的增殖,并显著下调K562细胞VEGF蛋白和mRNA的表达。同时,药物预处理细胞的条件培养基,其促内皮细胞增殖和促CAM血管新生的能力都有所下降,并呈药物浓度依赖性。结论二氢青蒿素能显著下调K562细胞VEGF的表达,并能抑制由其诱导的血管新生作用。  相似文献   

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Prostate cancer is the most commonly diagnosed malignancy in men and shows a tendency for metastasis to distant organs. Angiogenesis is required for metastasis. Bradykinin (BK) is an inflammatory mediator involved in tumor growth and metastasis, but its role in vascular endothelial growth factor (VEGF) expression and angiogenesis in human prostate cancer remains unknown. The aim of this study was to examine whether BK promotes prostate cancer angiogenesis via VEGF expression. We found that exogenous BK increased VEGF expression in prostate cancer cells and further promoted tube formation in endothelial progenitor cells and human umbilical vein endothelial cells. Pretreatment of prostate cancer with B2 receptor antagonist or small interfering RNA (siRNA) reduced BK-mediated VEGF production. The Akt and mammalian target of rapamycin (mTOR) pathways were activated after BK treatment, and BK-induced VEGF expression was abolished by the specific inhibitor and siRNA of the Akt and mTOR cascades. BK also promoted nuclear factor-κB (NF-κB) and activator protein 1 (AP-1) activity. Importantly, BK knockdown reduced VEGF expression and abolished prostate cancer cell conditional medium-mediated angiogenesis. Taken together, these results indicate that BK operates through the B2 receptor, Akt, and mTOR, which in turn activate NF-κB and AP-1, activating VEGF expression and contributing to angiogenesis in human prostate cancer cells.  相似文献   

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Recent findings on the inhibition of angiogenesis and vascular endothelial cell proliferation by anthracycline antibiotics, which contain a quinone moiety, make this type of compound a very promising lead in cancer research/therapy. We have reported that a new cannabinoid anticancer quinone, cannabidiol hydroxyquinone (HU-331), is highly effective against tumor xenografts in nude mice. For evaluation of the antiangiogenic action of cannabinoid quinones, collagen-embedded rat aortic ring assay was used. The ability of cannabinoids to cause endothelial cell apoptosis was assayed by TUNEL staining and flow cytometry analysis. To examine the genes and pathways targeted by HU-331 in vascular endothelial cells, human cDNA microarrays and polymerase chain reaction were used. Immunostaining with anti-CD31 of tumors grown in nude mice served to indicate inhibition of tumor angiogenesis. HU-331 was found to be strongly antiangiogenic, significantly inhibiting angiogenesis at concentrations as low as 300 nM. HU-331 inhibited angiogenesis by directly inducing apoptosis of vascular endothelial cells without changing the expression of pro- and antiangiogenic cytokines and their receptors. A significant decrease in the total area occupied by vessels in HU-331-treated tumors was also observed. These data lead us to consider HU-331 to have high potential as a new antiangiogenic and anticancer drug.  相似文献   

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Aim:This study was carried out to identify the role of adiponectin (APN) in modulating the expression of vascular endothelial growth factor (VEGF) and pigment epithelial-derived factor (PEDF) in relation to ocular angiogenesis.Results:ARPE cells exposed to APN showed decreased expression of VEGF mRNA, protein whereas PEDF protein is unaltered and PEDF mRNA was increased.Conclusion:Our in vitro study on ARPE exposed to APN showed a negative correlation with VEGF levels. Thus indicating the protective role for APN in angiogenesis-related diseases.KEY WORDS: Adiponectin, pigment epithelium derived factor, proliferative diabetic retinopathy, vascular endothelial growth factor  相似文献   

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Angiogenesis is the formation of new blood vessels from the pre-existing vasculature. Besides its role in normal physiology, angiogenesis is significantly involved in many pathological conditions, including inflammation, cardiovascular diseases and cancer. Numerous studies have been undertaken in the area of tumor angiogenesis. It is known that pathological angiogenesis is necessary for tumors to proceed from avascular, dormant stage to vascular, sprouting stage and also contributes to their later invasion and metastasis. Playing a central role in tumor angiogenesis, vascular endothelial growth factor is considered as a key target in therapeutic approaches. This article aims to review the critical role of VEGF in tumor angiogenesis and the importance of VEGF-targeted strategies in cancer treatment.  相似文献   

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Insulin-like growth factor binding protein-7 (IGFBP7) and vascular endothelial growth factor (VEGF) are expressed in vascular endothelial cells in several tumor types. In this study, we examined the effect of IGFBP7 on VEGF-induced tube formation in cultured human umbilical vein endothelial cells (HUVECs) and its potential action in the modulation of VEGF signaling in vascular cells. IGFBP7 treatment suppressed VEGF-induced tube formation, proliferation, and the phosphorylation of mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) 1/2 in HUVECs. IGFBP7 attenuated VEGF-enhanced cyclooxygenase (COX)-2 and VEGF mRNA expression, and prostaglandin E2 secretion. Knocking down endogenous IGFBP7 enhanced COX-2 and VEGF mRNA expression. A significant increase in IGFBP7-induced caspases was not observed in the presence of VEGF. These findings indicate that IGFBP7 can modulate the stimulatory effect of VEGF on angiogenesis by interfering with VEGF expression as well as VEGF signaling and not by inducing apoptosis.  相似文献   

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