Insulin-like growth factor 2 (IGF2 ) and IGF-binding protein 1 (IGFBP1) gene variants are associated with overfeeding-induced metabolic changes

Aims/hypothesis. The aim of this study was to investigate the role of insulin-like growth factor 1 (IGF1), IGF2, IGF binding protein 1 (IGFBP1) and IGFBP3 gene variants on the metabolic changes observed in response to a 100-day overfeeding protocol conducted with 12 pairs of monozygotic twins. Methods: Genotyping was done by PCR-RFLP and DNA sequencer methods. Body fat measurements included hydrodensitometry and abdominal fat from computed tomography. Plasma glucose and insulin during fasting and in response to an OGTT were assayed. Plasma lipids were measured enzymatically. Results: In response to caloric surplus, fasting plasma insulin (p < 0.05) and OGTT insulin (p = 0.004) but not glucose area, increased more among the subjects with IGF2 Apa I GG (n = 12) than those with AA + AG (n = 12). The changes were independent of changes in total fatness. The subjects with IGFBP1 Bgl II AA (n = 8) showed greater increases in abdominal visceral fat (p < 0.01), OGTT insulin area (p = 0.05) and total cholesterol (p < 0.03) with overfeeding than the subjects with AG + GG (n = 16). IGFBP3 Nde I and the IGF1 (CT)_n markers were not associated with responsiveness to overfeeding. Conclusion/interpretation: Insulin sensitivity decreased in the subjects with IGF2 Apa I GG and the subjects with IGFBP1 Bgl II AA showed an accumulation of abdominal visceral fat and the early symptoms of the metabolic syndrome after long-term caloric surplus. Genetic variation at the IGF2 and IGFBP1 loci could be among the factors responsible for the inter-individual differences observed in the response to long-term alterations in energy balance and should be further investigated in larger cohorts. [Diabetologia (2001) 44: 2231–2236] Received: 26 March 2001 and in revised form: 31 August 2001     

丁苯酞动员内皮祖细胞治疗脑缺血再灌注大鼠实验研究

目的观察丁苯酞治疗对脑缺血再灌注大鼠的影响。方法选取健康雄性SD大鼠60只,随机分为假手术组、模型组、尼莫地平组[12mg/(kg·d)]和低剂量组[丁苯酞60mg/(kg·d)]和高剂量组[丁苯酞120mg/(kg·d)],线栓法建立大脑中动脉缺血再灌注模型。各组灌胃治疗5d,每天行神经功能缺损评分;流式细胞仪检测缺血2h和治疗5d后循环内皮祖细胞(EPC)水平;行CD31及血管性假血友病因子(vWF)免疫组织化学染色,观察大鼠脑缺血区血管新生情况。结果治疗第2天起,尼莫地平组及高、低剂量组神经功能评分均显著低于模型组(P<0.05),第3天时高剂量组神经功能缺损评分低于低剂量组[(0.40±0.52)分vs(1.10±0.32)分,P<0.05]。假手术组大鼠缺血2h循环EPC水平低于其他4组(P<0.05)。治疗第5天,高剂量组EPC增加的水平明显高于模型组、尼莫地平组和低剂量组(P<0.05)。尼莫地平组及低剂量组和高剂量组脑缺血区CD31阳性及vWF阳性细胞数多于模型组。结论丁苯酞可动员循环EPC,促进缺血区血管新生,改善神经功能,呈剂量依赖性。     

MMP-3和VEGF在胰腺癌中的表达及临床意义

目的:探讨MMP-3和VEGF蛋白在胰腺癌组织中的表达及其与胰腺癌临床病理特征、预后及胰腺癌组织中血管新生的关系.方法:用免疫组织化学检测了56例手术切除的胰腺癌组织和正常胰腺组织中MMP-3、VEGF的蛋白表达和微血管密度,并请相关专业人员进行微血管密度计数分析.结果:在56例胰腺癌标本中有42例MMP-3(75.0...     

复元胶囊对兔膝骨关节炎软骨中胰岛素样生长因子-I及胰岛素样生长因子结合蛋白3表达的影响

目的 观察复元胶囊对兔膝骨关节炎软骨中胰岛素样生长因子-I (IGF-I)、胰岛素样生长因子结合蛋白3(IGFBP3)表达的影响.方法 采用右后肢伸直石膏固定法造模,将44只雌雄各半新西兰大白兔随机分为正常组、模型组、盐酸氨基葡萄糖组、复元胶囊低、中、高剂量组.正常组4只,其余各组8只.各药物组每天灌胃1次,持续6 w.免疫组织化学法检测IGF-I、IGFBP3表达.结果 模型组IGF-I、IGFBP3表达积分明显高于正常组(P<0.01);复元胶囊各剂量组与模型组比较,IGF-I表达积分不同程度升高(P<0.05),而IGFBP3表达积分不同程度降低(P<0.01),高剂量组显著.结论 复元胶囊具有防治膝骨关节炎作用,其机制可能与调节IGF-I、IGFBP3表达水平有关.     

The insulin‐like growth factor binding protein 3 ternary complex is reduced in cirrhosis

Abstract: Background/Aims: In healthy adults, serum insulin‐like growth factor I (IGF‐I), IGF binding protein 3 (IGFBP‐3) and acid labile subunit (ALS) form a 150‐kDa ternary complex under the control of growth hormone (GH). Approximately 80–90% of circulating IGF‐I is bound to the ternary complex. In cirrhosis the GH/IGF axis is severely disturbed and the individual components of the ternary complex are reduced. However, the degree of ternary complex formation in cirrhosis has not previously been described. Methods: Serum IGF‐I, IGFBP‐3, ALS, the 150‐kDa ternary complex and IGFBP‐3 proteolysis were all measured in six compensated and six decompensated cirrhotic patients and compared to six healthy controls. Results: Patients with compensated cirrhosis had decreased levels of IGF‐I (55%), IGFBP‐3 (64%) and ALS (53%), and in the decompensated patients these levels were decreased even further: IGF‐I (32%), IGFBP‐3 (37%) and ALS (27%) compared to healthy controls. The levels of the ternary complex followed this pattern, with low levels seen in the compensated patients (66%) and a further reduction in the decompensated patients (27%). Ternary complex levels correlated negatively with the Child–Pugh score. No increase in IGFBP‐3 proteolysis was found in cirrhotic patients compared to healthy controls. Conclusion: Cirrhosis is associated with reduced levels of the 150‐kDa ternary IGFBP‐3 complex correlating with the degree of liver disease.     

缺氧条件下血管活性因子对血管内皮细胞中血管内皮生长因子表达的影响

目的　探讨在缺氧条件下人脐静脉血管内皮细胞血管内皮生长因子 (VEGF)表达及缩血管活性物质内皮素 ,舒血管活性物质NO和NO抑制剂LNNA对VEGF基因表达的影响。方法　体外培养人脐静脉血管内皮细胞 ,经缺氧及血管活性物质处理 ,Northern杂交、酶联免疫检测和计算机图像分析等观察VEGFmRNA和蛋白表达水平。结果　缺氧 6h内皮细胞可见VEGF表达。ET可促进VEGFmRNA的表达 ,NO可明显抑制VEGFmRNA的表达 ,NO抑制剂LNNA也影响VEGFmRNA的表达。ELISA检测VEGF蛋白水平分别为 6h组 (8 2± 1 1) μg/L ,ET +6h组 (9 37± 1 0 2 ) μg/L ,NO +6h组 (2 86± 0 91) μg/L ,LNNA +6h组 (14 75± 1 87)μg/L。 结论　缺氧可诱导人脐静脉血管内皮细胞分泌VEGF并受血管活性物质的调控 ,ET促进其表达 ,NO抑制其表达。     

同型半胱氨酸对血管内皮细胞E-选择素、IL-6分泌的影响

目的探讨同型半胱氨酸（homocysteine,Hcy）对人脐静脉内皮细胞E-选择素、白细胞介素6（IL6）分泌的影响。方法在人脐静脉内皮细胞ECV304培养基中加入不同浓度Hcy,孵育不同时间,用ELISA法分别测定培养上清液中E-选择素及IL6的含量。结果终浓度为250μmol/L的Hcy孵育内皮细胞,E选择素的分泌在4h显著上调,6h达峰值;IL6的分泌在6h开始升高,24h达峰值,之后随着时间的延长逐渐下降。Hcy呈浓度依赖性（50μmol/L～500μmol/L）促进内皮细胞E选择素及IL6的分泌。结论Hcy能刺激血管内皮细胞分泌E选择素及IL6。     

血管内皮生长因子调节内皮祖细胞生物学功能

目的研究血管内皮生长因子（VEGF）对体外培养骨髓源性内皮祖细胞（EPCs）数量及增殖、迁移、黏附功能的影响及机制初探。方法密度梯度离心法获取骨髓单个核细胞,FITC-荆豆凝集素I、DiI-乙酰化低密度脂蛋白荧光双染鉴定。单个核细胞培养7d后分为对照组和VEGF干预组。VEGF干预组加入不同浓度VEGF（25,50,75,100μg／L）培养48h,分别采用四氮唑溴盐比色法、改良的Boyden小室和黏附能力测定观察EPCs的增殖、迁移和黏附能力。RT—PCR法半定量检测VEGF对EPCs内皮型一氧化氮合酶（eNOS）mRNA表达的影响。硝酸还原酶法比色测定VEGF对EPCs分泌一氧化氮的影响。结果VEGF可浓度依赖性地增加EPCs数量并明显促进EPCs的黏附、迁移和增殖能力,与对照组比较差异显著。VEGF可上调EPCseNOSmRNA的表达,促进EPCs分泌一氧化氮。结论VEGF可能通过上调EPCseNOSmRNA的表达影响EPCs部分生物学功能。     

坎地沙坦预处理对脑缺血再灌注大鼠血管内皮生长因子表达的影响

目的 探讨坎地沙坦预处理对脑缺血大鼠的血管保护作用.方法 48只雄性SpragurDawley大鼠,随机分为假手术组、缺血再灌注组以及坎地沙坦小剂量组[0.1 mg/(kg·d)]和大剂量组[1 mg/(kg·d)],每组12只;各组又随机分为缺血2 h后再灌注24 h和再灌注72 h亚组(每组6只).药物灌胃4周后,采用线栓法制备大脑中动脉闭塞模型,术前测量血压,分别在再灌注24 h和72 h后进行神经功能评分,然后断头取脑,采用2,3,5-氯化三苯基四氮唑染色测定脑梗死体积,通过免疫组化染色和Western印迹分析检测缺血区脑组织血管内皮生长因子(vascular endothelial growth factor,VEGF)蛋白表达.结果 坎地沙坦小剂量组和大剂量组再灌注24 h和72 h神经功能评分均显著优于缺血再灌注组(P分别为0.008和0.001),脑梗死体积显著缩小(P分别为0.010和0.000).坎地沙坦大剂量组在干预后第2周血压明显下降,小剂量组无明显降压作用.VEGF阳性表达主要分布于梗死灶周围区血管内皮细胞,其表达随时间推移进一步上调,再灌注72 h达峰值.Western印迹分析与免疫组化染色结果一致.结论 坎地沙坦可能通过上调缺血区VEGF表达缩小脑梗死体积,改善神经功能评分.     

尿酸盐致血管内皮细胞损伤的机制

目的观察不同浓度尿酸盐对人血管内皮细胞损伤相关因子表达的影响,明确高尿酸血症对人血管内皮细胞的损伤的机制。方法体外单独培养人血管内皮细胞或与单核细胞共培养,尿酸盐分别用6．6mg／dl（约为人体男、女高尿酸血症最低值平均值）及该值2、3、4、5倍值刺激血管内皮细胞48小时,用酶联免疫吸附双抗体夹心法（ELISA）测定上清液白细胞介素1（IL-1）、肿瘤坏死因子α（TNF-d）、细胞间粘附分子-1（ICAM-1）、血浆纤溶酶原激活抑制剂-1（PAI-1）等因子表达水平,用逆转录-聚合酶链式反应（RT-PcR）测定血管内皮细胞人尿酸盐转运子（hUAT）mRNA的表达。结果①不同浓度尿酸盐与血管内皮细胞单独培养：结果显示高浓度尿酸盐使血管内皮细胞IL-l、TNF-Ⅸ、ICAM-1、PAI-1的表达上调,明显高于对照组（P均〈0．05）;②不同浓度尿酸盐与血管内皮细胞及单核细胞共培养：结果显示高浓度尿酸盐使血管内皮细胞IL-1、TNF-α、ICAM-1、PAI-1的表达进一步增高,明显高于对照组（P均〈0．05）;③hUATmRNA表达：高浓度尿酸盐使血管内皮细胞hUATmRNA表达明显低于对照组（P〈0．05）;与单核细胞共培养高浓度尿酸盐使血管内皮细胞hUATmRNA表达明显进一步下调（P〈0．05）。结论尿酸盐可以作为独立的危险因素引起内皮细胞的直接损伤,单核细胞在内皮细胞损伤过程中亦起到了重要作用,血管内皮细胞和单核细胞共培养使血管内皮细胞损伤进一步加重。     

通心络下调caspase-3蛋白表达及活性抑制软脂酸诱导的人外周血内皮祖细胞凋亡

目的:探讨通心络(tongxinluo,TXL)对软脂酸(palmitic acid,PA)诱导的人外周血内皮祖细胞(endothelialprogenitor cell,EPCs)凋亡及caspase-3蛋白表达和活性的影响。方法:密度梯度离心法获取人外周血单个核细胞,培养7d后,贴壁细胞分成7组:对照组以M199培养液培养48h;PA各浓度组(共3组)分别用含200,400,800μmol/L PA的M199培养液孵育48h;通心络干预组(共3组)分别先用含100,200,400μmol/L TXL的M199培养液干预2h后,再加入400μmol/L PA孵育48h。采用流式细胞仪检测细胞凋亡率;提取细胞蛋白,采用Westernblot技术检测caspase-3蛋白表达水平;采用分光光度法检测caspase-3蛋白活性水平。结果:PA呈浓度依赖性诱导EPCs凋亡;加入TXL干预,EPCs细胞凋亡率明显降低;Western blot和分光光度法检测显示,PA组EPCs的caspase-3蛋白表达及活性明显高于对照组,200和400μmol/L TXL干预组明显低于PA组(P0.05)。结论:PA呈浓度依赖性诱导EPCs凋亡,TXL能部分抑制PA的上述作用,其机制与下调caspase-3蛋白表达及活性有关。     

血管内皮细胞衰老与心血管疾病的相关性

血管内皮细胞(VEC)是覆盖于血管内膜表面的单层扁平鳞状上皮细胞,其构成血管壁的生物屏障,不仅属于一种保护性屏障,还能够产生一些自体分泌物用于调节体内平衡和血管紧张度。VEC衰老可导致血管功能受损,是心血管系统(CVS)主要的危险因素,并与心血管疾病(CVD)有着密切的关系。然而,VEC衰老的机制以及VEC衰老对血管功能的影响尚不完全清楚。本综述总结了VEC衰老的特征及其相关分子机制,并对年龄相关CVD进行了阐述。     

小干扰RNA对大鼠血管内皮细胞ICAM-1表达的抑制作用

目的:探讨小干扰RNA对大鼠血管内皮细胞细胞间黏附分子-1(ICAM-1)表达的抑制作用.方法:使用 ICAM-1siRNA及错配siRNA转染肿瘤坏死因子-α刺激过的大鼠血管内皮细胞,聚合酶链反应和蛋白印迹检测转染后48 h ICAM-1 mRNA和蛋白表达水平.结果:与空白对照组比较,大鼠血管内皮细胞在转染48 h后ICAM-1 mRNA表达减少90.0％,蛋白表达减少83.0％.结论:使用小干扰RNA能有效抑制大鼠血管内皮细胞ICAM-1表达.     

高糖诱导血管内皮细胞损伤的调控机制研究进展

目前关于高糖诱导血管内皮细胞损伤的机制有多种,包括非酶促糖基化终产物的积聚、二酰甘油／蛋白激酶c通路的激活及氧化应激的增强等。这些途径都是被高糖激活的,彼此之间又能相互作用。     

Melatonin prevents human pancreatic carcinoma cell PANC-1-induced human umbilical vein endothelial cell proliferation and migration by inhibiting vascular endothelial growth factor expression

Abstract: Melatonin is an important natural oncostatic agent, and our previous studies have found its inhibitory action on tumor angiogenesis, but the mechanism remains unclear. It is well known that vascular endothelial growth factor (VEGF) plays key roles in tumor angiogenesis and has become an important target for antitumor therapy. Pancreatic cancer is a representative of the most highly vascularized and angiogenic solid tumors, which responds poorly to chemotherapy and radiation. Thus, seeking new treatment strategies targeting which have anti‐angiogenic capability is urgent in clinical practice. In this study, a co‐culture system between human umbilical vein endothelial cells (HUVECs) and pancreatic carcinoma cells (PANC‐1) was used to investigate the direct effect of melatonin on the tumor angiogenesis and its possible action on VEGF expression. We found HUVECs exhibited an increased cell proliferation and cell migration when co‐cultured with PANC‐1 cells, but the process was prevented when melatonin added to the incubation medium. Melatonin at concentrations of 1 μm and 1 mm inhibited the cell proliferation and migration of HUVECs and also decreased both the VEGF protein secreted to the cultured medium and the protein produced by the PANC‐1 cells. In addition, the VEGF mRNA expression was also down‐regulated by melatonin. Taken together, our present study shows that melatonin at pharmacological concentrations inhibited the elevated cell proliferation and cell migration of HUVECs stimulated by co‐culturing them with PANC‐1 cells; this was associated with a suppression of VEGF expression in PANC‐1 cells.     

血管内皮生长因子在门脉高压患者胃黏膜的表达

目的探讨血管内皮生长因子(VEGF)在肝硬化门脉高压(PHT)患者胃黏膜的表达及其在门脉高压性胃病(PHG)发病中的作用。方法分别采集PHG、PHT和正常对照组胃黏膜组织。应用免疫组化法检测胃黏膜VEGF蛋白的表达。PHG程度按改良的McMrmark’s分级由有经验的消化科医师盲法评估。结果PHG组(49.56%±12.26%)和PHT组(48.56%±12.23%)胃黏膜VEGF表达较正常对照组(5.11%±2.14%)显著性增高(P<0.05),但前两组间VEGF的表达无统计学差异(P>0.05)。VEGF阳性表达主要见于胃小凹颈部黏膜细胞浆内。VEGF与PHG积分呈显著性正相关(H=10.592,P<0.05)。结论肝硬化门脉高压患者胃黏膜组织VEGF表达增高。PHT胃黏膜淤血、缺氧与VEGF增加存在互动关系,VEGF在PHG发病过程中的作用可能是有限的。     

黑龙江立克次体感染血管内皮细胞的初步研究

目的 通过黑龙江立克次体感染体外培养人脐静脉内皮细胞（human umbilical vein endothelial cells, HUVEC）探讨其在内皮细胞内的生长规律。方法 将泛影葡胺密度梯度超速离心纯化的黑龙江立克次体（HLJ-054株）感染体外培养的HUVEC,通过间接免疫荧光和扫描电镜检测与观察不同时相黑龙江立克次体在内皮细胞内的生长状况。热灭活黑龙江立克次体做平行对照。 结果 立克次体粘附并侵入内皮细胞,在感染后第6h及第24h分别为感染高峰;感染5 d后细胞内立克次体逐渐增殖,第8～9d细胞内立克次体急剧增殖,并见细胞核内有少量立克次体,细胞出现病变,第12d细胞内充满立克次体,大部分细胞皱缩脱落。结论 黑龙江立克次体能够感染血管内皮细胞,在血管内皮细胞内不断增殖而使细胞死亡。