益气活血复方含药血清对人脐静脉内皮细胞TLR4/NF-ΚB信号通路及TNF-a ICAM-1 mRNA表达的影响

目的:研究益气活血复方含药血清对脂多糖(LPS)诱导的人脐静脉内皮细胞(HUVECs)Toll样受体4(TLR4)/NF-KB及肿瘤坏死因子-a(TNF-a)、细胞间黏附分子(ICAM-1)mRNA表达的影响,探讨益气活血复方含药血清防治动脉粥样硬化(AS)的机制。方法:(1)选择新西兰大耳白兔20只,随机分为4组,即正常组、中药高浓度组、中药中浓度组、中药低浓度组,每组5只。以上各组白兔分别以生理盐水和高、中、低浓度益气活血复方连续灌胃7天。末次灌胃给药2h后,心脏采血,离心后分离血清。(2)体外培养人脐静脉内皮细胞,用LPS刺激后,分别加入高、中、低浓度益气活血复方含药血清干预24h,收集细胞,用荧光定量PCR方法测定TLR4、NF-KB、TNF-a及ICAM-1 mRNA的表达。结果:用LPS刺激人脐静脉内皮细胞后,引起TLR4、NF-KB、TNF-a及ICAM-1 mRNA的高表达(与空白对照组比较P<0.01),用益气活血复方含药血清干预以后显著抑制TLR4、NF-KB、TNF-a及ICAM-1 mRNA的高表达(与模型组比较P<0.01或P<0.05)。结论:益气活血复方可阻断TLR4/NF-KB...     

Dioxin-induced toxicity on vascular remodeling of the placenta

Arylhydrocarbon receptor (AhR) activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) triggers its downstream signaling pathway to exert adverse effects on vasculature development, which can be initiated by vasculogenesis, followed by angiogenesis, or vascular remodeling, in a variety of animals including avians, piscines and mammals. The placenta, a mammalian organ rich in vasculature, consists of endothelial and trophoblast cells of fetal origin, which proliferate and differentiate under hypoxic condition in the uterine horn. Our studies demonstrated that vascular remodeling occurs prominently in the placenta of the control Holtzman rat strain during the late period of gestation, and induces changes in cell shape and elimination by apoptosis of trophoblasts. As a result, the net volumes of both maternal and fetal blood in the placenta increase to cope with the essential requirements of oxygen and nutrients in the late period of gestation. On the other hand, in utero exposure to TCDD markedly suppressed the development of sinusoids and trophoblast cells and the apoptosis of trophoblast cells with a concomitant increase in the incidence of fetal death under hypoxic condition. A crosstalk between the hypoxia-inducible factor (HIF)-mediated pathway and AhR-mediated pathway is considered to play an important role in this physiological process. No such changes were observed in the Sprague-Dawley rat strain that turned out to have an AhR conformation identical to that of the Holtzman rat strain. In this commentary, we will discuss a possible link of the TCDD toxicities with the AhR signaling pathway and gestation-related diseases.     

In vivo toxicity studies of europium hydroxide nanorods in mice

Lanthanide nanoparticles and nanorods have been widely used for diagnostic and therapeutic applications in biomedical nanotechnology due to their fluorescence and pro-angiogenic properties to endothelial cells, respectively. Recently, we have demonstrated that europium (III) hydroxide [Eu^III(OH)₃] nanorods, synthesized by the microwave technique and characterized by several physico-chemical techniques, can be used as pro-angiogenic agents which introduce future therapeutic treatment strategies for severe ischemic heart/limb disease, and peripheral ischemic disease. The toxicity of these inorganic nanorods to endothelial cells was supported by several in vitro assays. To determine the in vivo toxicity, these nanorods were administered to mice through intraperitoneal injection (IP) everyday over a period of seven days in a dose dependent (1.25 to 125 mg kg^− 1 day^− 1) and time dependent manner (8–60 days). Bio-distribution of europium elements in different organs was analyzed by inductively coupled plasma mass spectrometry (ICPMS). Short-term (S-T) and long-term (L-T) toxicity studies (mice euthanized on days 8 and 60 for S-T and L-T, respectively) show normal blood hematology and serum clinical chemistry with the exception of a slight elevation of liver enzymes. Histological examination of nanorod-treated vital organs (liver, kidney, spleen and lungs) showed no or only mild histological changes that indicate mild toxicity at the higher dose of nanorods.     

Dieckol isolated from Ecklonia cava inhibits α-glucosidase and α-amylase in vitro and alleviates postprandial hyperglycemia in streptozotocin-induced diabetic mice

This study was designed to investigate whether dieckol may inhibit α-glucosidase and α-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. Dieckol isolated from Ecklonia cava, brown algae, evidenced prominent inhibitory effect against α-glucosidase and α-amylase. The IC₅₀ values of dieckol against α-glucosidase and α-amylase were 0.24 and 0.66 mM, respectively, which evidenced the higher activities than that of acarbose. Dieckol did not exert any cytotoxic effect in human umbilical vein endothelial cells (HUVECs) at various concentrations (from 0.33 to 2.69 mM). The increase of postprandial blood glucose levels were significantly suppressed in the dieckol administered group than those in the streptozotocin-induced diabetic or normal mice. Moreover, the area under curve (AUC) was significantly reduced via dieckol administration (259 versus 483 mmol min/l) in the diabetic mice as well as it delays absorption of dietary carbohydrates. Therefore, these result indicated that dieckol might be a potent inhibitor for α-glucosidase and α-amylase.     

雷公藤内脂醇在体外人脐静脉血管内皮细胞的c-fos基因mRNA的表达

目的 探讨雷公藤内酯醇对体外培养的血管内皮细胞c-fos基因mRNA表达的方式的作用及机理,为角膜碱烧伤后新生血管的增生抑制提供一种可能的理论依据.方法 人脐静脉获取血管内皮细胞,体外培养成功后,在细胞增殖的同时分别加入不同浓度的雷公藤内酯醇,以原位分子杂交方法检测不同浓度雷公藤内酯醇对血管内皮细胞c-fos基因mRNA表达的影响.结果 c-fos原位分子杂交染色结果表明正常HUVEC c-fos mRNA表达阳性,加入雷公藤内酯醇后呈剂量依赖性地抑制c-fos mRNA的表达.结论 ①雷公藤内酯醇可能通过抑制c-fos基因表达进而影响转录因子AP-1的形成.②雷公藤内酯醇通过抑制c-fos基因表达进而抑制血管内皮细胞的复制.     

重组梅毒螺旋体蛋白Tp47通过诱导uPA增加血管内皮细胞通透性

目的探讨重组梅毒螺旋体蛋白Tp47(rTpp47)对单核-巨噬细胞系THP-1合成尿激酶型纤溶酶原激活物(uPA)的调控及其对人脐静脉/血管内皮细胞(HUVECs)通透性的影响。方法用rTpp47刺激THP-1细胞24 h后,分别收集细胞培养上清和THP-1细胞,用ELISA和Western blot检测THP-1细胞表达的uPA含量;用THP-1细胞培养上清刺激人单层血管内皮细胞后,使用FITC-葡聚糖评价单层内皮细胞通透性的变化,用Western blot检测uPA对HUVECs细胞紧密连接蛋白claudin-5表达的影响以及PKC信号通路是否参与rTpp47诱导的THP-1细胞表达uPA。结果重组蛋白rTpp47刺激THP-1细胞合成和分泌的uPA显著高于对照组(P<0.05,P<0.001);用rTpp47与THP-1细胞共培养24 h后收集的细胞培养上清刺激单层血管内皮细胞12和24 h,实验组血管内皮细胞相对通透性显著高于对照组(P<0.05,P<0.000 1);uPA活性抑制剂阿米洛利(amiloride)抑制了rTpp47刺激THP-1细胞分泌...     

桂郁金多糖对H2O2致人脐静脉内皮细胞损伤的保护作用及机制

目的:通过体外实验研究不同质量浓度桂郁金多糖对过氧化氢(H_2O_2)致人脐静脉内皮细胞损伤的的保护作用及机制。方法:对人脐静脉内皮细胞(HUVECs)进行体外培养,用不同浓度H_2O_2损伤HUVECs,采用细胞增殖/毒性检测试剂盒(CCK-8),确定H_2O_2最佳损伤浓度为500μmol·L~(-1)。然后给予不同浓度的桂郁金多糖对损伤的HUVECs进行保护,用CCK-8,确定62.5,125,250 mg·L~(-1)作为桂郁金多糖的低、中、高质量浓度组。采用CCK-8法检测桂郁金多糖对H_2O_2损伤HUVECs细胞活力的影响;采用试剂盒测定乳酸脱氢酶(LDH),超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GSH-Px),丙二醛(MDA);通过酶联免疫吸附测定(ELISA)检测细胞中肿瘤坏死因子-α(TNF-α),白细胞介素-6(IL-6)的含量表达。采用Hoechst 33258荧光染色法对细胞凋亡情况进行观察;并采用实时荧光定量聚合酶链式反应(Real-time PCR)测定细胞中B淋巴细胞瘤-2(Bcl-2),Bcl-2相关X蛋白(Bax),半胱氨酸蛋白酶-3(Caspase-3)mRNA的表达情况。结果:CCK-8检测结果表明,给药时间24 h后,桂郁金多糖在15.625~500 mg·L~(-1),能够促进细胞增殖,而浓度增大后,桂郁金多糖则对细胞有一定的抑制作用。与模型组比较,桂郁金多糖能够使LDH,MDA,IL-6,TNF-α水平明显减少(P0.05,P0.01),使SOD和GSH-Px的含量明显增加(P0.05,P0.01)。Hoechst 33258荧光染色结果表明,与空白组比较,模型组HUVECs细胞核呈亮蓝色荧光,细胞质内可见浓染致密的颗粒块状荧光,细胞密度降低;与模型组比较,桂郁金多糖给药组的蓝色荧光强度降低,细胞凋亡典型形态减少。Real-time PCR实验结果显示,与空白组比较,模型组减少Bcl-2 mRNA的表达,增加Bax,Caspase-3 mRNA的表达(P0.05,P0.01);与模型组比较,桂郁金多糖给药组能够增加Bcl-2 mRNA的表达(P0.05,P0.01),减少Bax,Caspase-3 mRNA的表达(P0.05,P0.01)。结论:桂郁金多糖通过抗氧化和抑制细胞凋亡等途径对H_2O_2损伤的人脐静脉内皮细胞进行保护。     

银杏叶提取物对脂多糖介导的血管内皮细胞低密度脂蛋白受体LOX-1表达的影响

[目的]观察银杏叶提取物（GBE50）对脂多糖（LPS）诱导的人脐静脉内皮细胞（HUVECs）氧化低密度脂蛋白受体（lectin like oxidized low density lipoprotein receptor,LOX-1）表达的影响.[方法]应用LPS刺激体外培养的HUVECs 24h.RT-PCR方法检测（lectin like oxidized low density lipoprotein receptor mRNA,LOX-1 mRNA）表达水平;采用蛋白质印迹分析检测LOX-1蛋白表达水平.[结果]LPS （1 μg/ mL）上调LOX-1 mRNA和蛋白表达水平,GBE50（40 μg/mL）轻度抑制LPS介导的LOX-1 mRNA（P＜0.005）和蛋白表达增加（但没有统计学意义,P＞0.05）,GBE50（80 μg/mL）及NF-κB抑制剂CAPE（20 μg/mL）明显抑制LOX-1 mRNA和蛋白表达上调（P＜0.01）.[结论] GBE50可能通过抑制LOX-1表达,在防治动脉粥样硬化中发挥作用.