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51.
AIM: To explore the effect of water extract propolis (WEP) from Taishan on apoptosis of human umbilical vascular endothelial cells (HUVECs) induced in vitro by tumor necrosis factor-α (TNF-α). METHODS: HUVECs were collect by digestion-perfusion and cultivated. TNF-α at concentration of 50 μg/L was administrated to induce the apoptosis of HUVECs. After injury, HUVECs were treated with WEP at concentrations of 50, 100, and 200 mg/L, respectively, for 24 h. Apoptosis was evaluated by terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) and flow cytometry (FCM). RESULTS: Apoptosis index in injured group was significantly higher than that in control group, and decreased significantly after treating with WEP at concentrations of 50, 100, and 200 mg/L, respectively (P<0.01). CONCLUSION: WEP may be useful for protection of vascular endothelial cells by inhibiting apoptosis.  相似文献   
52.
AIM: To observe the effects and mechanisms of nitroglycerin (NTG) on cell viability and β-mercaptoethanol (β-ME) on ameliorating nitrate tolerance of peripheral blood-derived endothelial progenitor cells (EPCs) in coronary heart disease (CAD) patients.METHODS: We studied 75 patients with diagnosis of coronary artery disease who were assigned to control group and NTG group. EPCs were evaluated by flow cytometry. Vascular endothelial growth factor-A (VEGF-A) and peroxynitrite anion (ONOO-) production were measured by ELISA. EPCs were cultured in vitro with NTG and β-ME stimulation. The cell viability was determined by MTT assay. The levels of VEGF-A, ONOO- and reactive oxygen species (ROS) were measured by ELISA and DCFH-DA assay. The protein levels of Akt,p-Akt,endothelial nitric oxide synthase (eNOS) and p-eNOS were determined by Western blot. RESULTS: Compared with the control group, the circulating EPCs levels were significantly lowered, plasma ONOO- production was vitally increased, but there was a markedly decrease of VEGF-A production in the patients treated with excess NTG(P<0.05). Moderate dose of NTG increased the viability of EPCs, VEGF-A production, and phosphorylated protein levels of Akt and eNOS. Excess NTG was shown to reverse the effect of moderate dose of NTG, but β-ME improved the adverse effect of excess NTG. CONCLUSION: Moderate dose of NTG effectively promotes EPCs viability by PI3K/Akt/eNOS signaling pathway and β-ME improves NTG-induced tolerance by reducing oxidative stress and up-regulating the PI3K/Akt/eNOS signaling pathway.  相似文献   
53.
AIM:To investigate the effect of shikonin on the apoptosis and oxidative stress induced by high concentration of glucose in vascular endothelial cells. METHODS:Rat thoracic aortic endothelial cells were randomly divided into 5 groups:normal control group (with glucose at concentration of 5.5 mmol/L in cell culture medium), high glucose group (with glucose at concentration of 33 mmol/L in cell culture medium), high glucose+low shikonin group (with glucose at concentration of 33 mmol/L and shikonin at concentration of 0.1 μmol/L in cell culture medium), high glucose+medium shikonin group (with glucose at concentration of 33 mmol/L and shikonin at concentration of 1 μmol/L in cell culture medium), and high glucose+high shikonin group (with glucose at concentration of 33 mmol/L and shikonin at concentration of 10 μmol/L in cell culture medium). After treatments, the cell viability was measured by CCK-8 assay and cell apoptotic rate was analyzed by flow cytometry. In addition, the status of oxidative stress was evaluated by determining the levels of malondialdehyde (MDA), reactive oxygen species (ROS), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). The activation of Nrf2/HO-1 signaling pathway was determined by Western blot. RESULTS:Compared with high glucose group, shikonin reversed high glucose-induced decrease in cell viability and increase in apoptosis in a concentration-dependent manner. High concentration of glucose induced high levels of MDA and ROS, while decreased the levels of SOD and GSH-Px. However, after treatment with shikonin, the contents of MDA and ROS were decreased, while the activities of SOD and GSH-Px were increased as compared with high glucose group. Furthermore, the high concentration of glucose up-regulated the protein levels of cleaved caspase-3, HO-1 and Nrf2 (nuclear). Compared with high glucose group, the protein levels of cleaved caspase-3, HO-1 and Nrf2 (nuclear) were partly decreased after treatment with shikonin. CONCLUSION:Shikonin alleviates high glucose-induced vascular endothelial cell apoptosis. Its mechanism may be related to activation of Nrf2/HO-1 signaling pathway and down-regulation of oxidative stress in vascular endothelial cells.  相似文献   
54.
AIM: To explore the effect of protein kinase D1 (PKD1) on promoting angiogenesis in vitro and in vivo, and to furnish a new idea on targeting PKD1 for the treatment of ischemic heart disease such as myocardial infarction. METHODS: The culture, isolation and identification of endothelial progenitor cells (EPCs) were performed in vitro. The effects of PKD1 and its specific blocking agent CID755673 on expression levels of vascular endothelial growth factor (VEGF) and kinase insert domain receptor (KDR) in EPCs were determined. The rat model of myocardial infarction was established, the intervention effects of PKD1 and CID755673 on morphology, changes of microvessels and endothelial cells, and the expression of VEGF and KDR in the impaired myocardial tissue were analyzed. RESULTS: PKD1 significantly upregulated the expression of VEGF and KDR in EPCs in vitro. Meanwhile, the structure of myocardial tissue was more regular and clear, the cytomembrane of endothelial cells were more smooth and integrity, the pericytes were visible, and the expression of VEGF and KDR was significantly increased in PKD1 treatment group in vivo.CONCLUSION: PKD1 has the ability of angiogenesis obviously, which might be mediated by VEGF.  相似文献   
55.
海南本地野生维管植物区系研究   总被引:1,自引:0,他引:1  
为全面了解海南本地野生维管植物区系基本特征,以《海南植物物种多样性编目》、《海南植物图志》等文献为基础,并通过野外考查、标本考证,从野生维管植物区系组成、成分等方面开展海南本地野生维管植物区系研究。结果表明:(1)海南维管植物共243科1 895属6 036种,其中本地野生维管植物有4 579种,隶属于225科1 429属,具有较高的物种多样性,但特有种占总种数的10.55%,仅483种;(2)在海南本地野生维管植物种类组成中,重要科有樟科(Lauraceae)、楝科(Meliaceae)、壳斗科(Fagaceae)、棕榈科(Palmae)、龙脑香科(Dipterocarpaceae)、五加科(Araliaceae)、漆树科(Anacardiaceae)等;(3)海南本地野生维管植物区系主要由以热带分布为主的科(占科数82.63%)和属(占属数84.40%)组成,其中,科以泛热带分布及其变型为主(57.49%),属以热带亚洲分布及其变型为主(27.09%),属马来西亚亚区的一部分,不仅呈现出热带性,而且呈现出与中国华南大陆的共源性,带有明显的热带边缘性质,为中国华南植物区系与亚洲热带雨林的过渡类型。  相似文献   
56.
时小艳 《西北农业学报》2016,25(12):1755-1761
旨在探讨血管内皮生长因子(VEGF-120)、促卵泡激素(FSH)、2-甲氧基雌二醇(2-ME2)、4-羟基雌二醇(4-OHE2)对卵泡生成的影响。通过对比试验,将试验组分别腹腔注射上述4种药品,一段时间后,HE染色统计分析卵巢中不同大小卵泡数量的变化、卵泡周围血管发育情况及定量分析VEGF、FLK-1表达情况。结果表明,VEGF-120组和FSH组大卵泡数增加,血管发育良好,VEGF和FLK-1基因表达增加;2-ME2和4-OHE2组大卵泡数减少,血管发育情况较差。综合分析发现,血管簇发育良好的卵泡生长状态良好,卵泡的生长与血管的发育存在一定关联。  相似文献   
57.
Changes to adhesion molecule expression and lymphocyte populations were evaluated in alveolar mammary tissue collected from cows following an immunisation protocol that involved intra-mammary inoculation to induce an IgA response in mammary secretions. The right quarters of the udder were immunised; the left side acted as a control. Antibody titres in secretions showed that at least two animals responded with antigen-specific IgA. Numbers of T-lymphocytes were 4-fold higher in immunised glands compared with controls (P < 0.05). IgA-, IgM- and IgG-positive cell numbers were significantly higher (P < 0.01) in immunised glands compared with controls in three of the four cows. No mucosal addressin molecule-1 (MAdCAM-1), vascular cell-adhesion molecule-1 (VCAM-1) or peripheral node addressin (PNAd) protein expression was detected on smaller venules that stained positively for von Willebrand factor in alveolar mammary tissues, from either immunised or control glands. Both VCAM-1 and PNAd were detected on smaller venules in supramammary lymph nodes, however, there was no significant difference between immunised and control glands. Quantification of MAdCAM-1 mRNA showed very low expression in both immunised and control alveolar tissue compared with Peyer's patch positive-control tissue. These findings suggest that the bovine mammary gland is capable of a mucosal antibody response; however, MAdCAM-1 is not involved with lymphocyte homing to the mammary gland in this species.  相似文献   
58.
59.
[目的]探讨ghrelin对蒙古绵羊脐静脉内皮细胞的血管内皮生长因子VEGF及其受体Flt-1mRNA表达的影响。[方法]试验分为4组:I组,空白对照组;II组,脂质体组;III组(SCON),20μmol/L正义寡核苷酸组;IV组(ASCON),20μmol/L反义寡核苷酸组。上述各组均在培养24、36、48h后,采用实时荧光定量方法检测VEGF及其受体Flt-1mRNA表达情况的变化。[结果]VEGFmRNA在I、II组表达量无差异,具有较高的表达量,随着时间的延长无明显变化;在III组VEGFmRNA表达略有降低,但与I和II组间无显著性差异(P>0.05);IV组(反义寡核苷酸组)的VEGFmRNA表达量显著下降(P<0.05),并且随着时间延长逐渐下降。VEGF受体FLT-1mR-NA的表达与VEGF相似。[结论]反义抑制ghrelin对VEGF及其受体Flt-1的mRNA表达有下调作用。  相似文献   
60.
血管内皮生长因子是血管特异性生长因子,有促进内皮细胞增生、转移,增加血管通透性和促进血管生成的作用.阐述了血管内皮生长因子的生物学特性和功能,以及血管内皮生长因子与缺血性脑血管病的关系.  相似文献   
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