非酶糖化蛋白对体外培养血管内皮细胞生长的影响

目的 观察糖代蛋白终末产物（ＡＧＥｓ）及高糖对体外培养人血管内皮细胞增殖的影响。方法 采用＾３Ｈ标记的腺嘧啶（＾３－ＴｄＲ）掺入法测定细胞增殖情况。结果 在含ＡＧＥｓ的培养液（５μｇ／ｍｌ）中增培养的新生儿脐带静脉内皮细胞,其２小时＾３Ｈ－ＴｄＲ掺入对照组的２．９５倍（Ｐ〈０．０１）,而在含３０ｍｍｏｌ／Ｌ葡萄糖的２液中培养的人胚胎脐带静脉内皮细胞,其２小时＾３Ｈ－ＴｄＲ掺入对照组（１１ｍｍｏｌ／     

Association between serum levels of soluble receptor for advanced glycation end products and circulating advanced glycation end products in type 2 diabetes

Aims/hypothesis Activation of the receptor for advanced glycation end products (RAGE, also known as AGE-specific receptor [AGER]) has been implicated in the development of diabetic vascular complications. Blockade of RAGE using a soluble form of the receptor (sRAGE) suppressed vascular hyperpermeability and atherosclerosis in animal models. Since little is known about the regulation of endogenous sRAGE levels, we determined whether serum sRAGE is influenced by circulating AGEs and the severity of nephropathy in type 2 diabetic patients.Materials and methods We recruited 150 healthy control and 318 diabetic subjects. Diabetic subjects were subdivided into those with proteinuria, microalbuminuria or normoalbuminuria. Serum sRAGE was assayed by ELISA and serum AGEs by competitive ELISA using a polyclonal rabbit antiserum raised against AGE-RNase.Results Diabetic subjects had higher sRAGE (1,029.5 pg/ml [766.1–1,423.0] interquartile range vs 1,002.6 [726.5–1,345.3], p<0.05) and AGEs (4.07±1.13, SD, unit/ml vs 3.39±1.05, p<0.01) than controls. Proteinuric subjects had the highest sRAGE levels and there was a significant trend between the severity of nephropathy and sRAGE (p=0.01). In diabetic subjects, serum log(sRAGE) correlated with AGEs (r=0.27, p<0.001), log(plasma creatinine) (r=0.31, p<0.001), log(urine AER) (r=0.24, p<0.01) and log(triglycerides) (r=0.15, p<0.01). On stepwise linear regression analysis, AGEs and creatinine levels were the main independent determinants of sRAGE concentration.Conclusions/interpretation Serum sRAGE levels and circulating AGEs are associated with the severity of nephropathy in type 2 diabetic patients. Prospective studies are required to determine whether endogenous sRAGE potentially influences the development of diabetic vascular complications.     

血红素加氧酶1在高糖和晚期糖基化终末产物诱导的THP-1细胞氧化应激中的作用

目的 探讨血红素加氧酶1(heme oxygenase-1,HO-1)在高糖和晚期糖基化终末产物(AGE)诱导的人单核细胞氧化应激中的作用.方法 根据是否加用15 mmoL/L葡萄糖(高糖)+100μg/ml AGE或HO-1抑制剂锌原卟啉(zinc protoporphyrin,ZnPP),将人单核细胞白m病细胞株THP-1细胞分为正常糖组(5 mmoL/L)、高糖+AGE组、高糖+AGE+ZnPP组、正常糖+ZnPP组,孵育24 h后收集细胞及培养液上清,榆测各组细胞的活性氧簇(ROS)、培养液上清丙二醛和肿瘤坏死因子α(TNF-α)水平以及HO-1 mRNA和蛋白的表达.结果 高糖+AGE组和正常糖+ZnPP组的ROS、丙二醛和TNF-α水平均显著高于正常糖组(均P<0.05).高糖+AGE+ZnPP组的ROS、TNF-α水平显著高于高糖+AGE组(均P<0.05).高糖+AGE+ZnPP组的HO-1 mRNA和蛋白表达水平显著低于高糖+AGE组(0.39+0.02±0.89 vs 0.09±0.384±0.00 vs 0.81±0.02,均P<0.05).结论 ZnPP通过抑制HO-1表达加重高糖和AGE导致的单核细胞氧化应激,HO-1可能在糖尿病氧化应激中起重要作用.     

糖基化终末产物诱导大鼠视网膜微血管内皮细胞表型和功能改变

目的 研究糖基化终末产物(AGEs)诱导大鼠视网膜微血管内皮细胞表型和功能的变化及相关机制.方法 SPF级雄性Wistar大鼠20只,7～8周龄,体重260～280 g,分离培养大鼠视网膜内皮细胞,采用免疫荧光染色、流式细胞术和体外形成毛细血管样网络结构的方法进行鉴定.视网膜内皮细胞在AGEs刺激后,用噻唑蓝(MTT)法分析细胞的增殖能力;用膜连蛋白V/碘化丙啶(Annexin V/PI)双染法检测细胞凋亡;采用逆转录聚合酶链反应(RT-PCR)和流式细胞术检测细胞AGEs受体、人蛋白激酶C(PKC)、细胞间黏附分子1(ICAM-1)和诱导型一氧化氮合酶(iNOS)的表达变化.采用t检验进行统计学分析.结果 分离纯化的大鼠视网膜内皮细胞表达血管性血友病因子(vWF)并在人工基膜上形成毛细血管网络结构.AGEs以时间和剂量依赖的方式抑制大鼠视网膜内皮细胞增殖能力,在200 mg/L的AGEs组培养至第5天时细胞增殖能力低于对照组(t=8.9,P＜0.05),7 d和9 d时抑制作用更明显(t值分别为15.7和46.1,均P＜0.01).400 mg/L AGEs组在第3天开始出现细胞增殖减慢(t=12.5,P＜0.05),从第5天开始增殖速度明显低于对照组(t值分别为22.4、41.5和77.7,均P＜0.01).并且AGEs诱导视网膜内皮细胞凋亡.进一步分析发现AGEs上调了大鼠视网膜内皮细胞AGEs受体、PKC、ICAM-1和iNOS的mRNA表达(t值分别为91.8、9.22、16和42,均P＜0.01)和蛋白水平的表达(t值分别为20.2、12.3、7.7和13.9,均P＜0.01).结论 AGEs可能通过上调AGEs受体诱导大鼠视网膜微血管内皮细胞表型和功能的改变.     

糖基化终末产物上调人胰岛微血管内皮细胞黏附分子的表达和白细胞黏附

目的 研究糖基化终末产物（AGEs）对人胰岛微血管内皮细胞（HIMVEC）黏附分子表达和白细胞黏附的影响.方法 HIMVEC细胞在200 mg/L的AGEs刺激后,用细胞基础的酶联免疫吸附法（ELISA）和Western blotting法检测细胞表面黏附分子的表达;并与BCECF标记的白细胞共培养检测与白细胞的黏附能力.采用实时荧光定量聚合酶链反应（RT-PCR）和Western blotting分别检测HIMVEC细胞上AGEs受体（RAGE）、蛋白激酶Cβ（PKC β）和蛋白激酶A（PKA）的mRNA表达情况.随后给予PKC β抑制剂LY333531或PKA激活剂8-Br-cAMP,观察对HIMVEC黏附分子表达的影响及和白细胞黏附的影响.两组间比较采用t检验进行分析.结果 与对照组相比,AGEs处理后HIMVEC表达P选择素、E选择素和血管细胞黏附分子1（VCAM-1）均上调（分别为1.10 ±0.13比0.64±0.14,0.83 ±0.06比0.47 ±0.05,0.87 ±0.09比0.43±0.07,t =4.93、9.40、7.61,均P＜0.05）,并且与白细胞的黏附较对照组明显增加（54 ±4比23 ±3,t=12.69,P＜0.05）.与AGEs组比较,RAGE抗体组P选择素、E选择素和VCAM-1的表达明显降低,组间差异具有统计学意义（t=5.69、6.89、5.43,均P＜0.05）.RAGE抗体组白细胞黏附明显少于AGEs组（54±4比31 ±4,t=8.22,P＜0.05）.与对照组相比,AGEs处理HIMVEC 4 h和18h,在mRNA水平和蛋白质水平均检测到RAGE和PKCβ的表达上调,但PKA的表达下调（t=10.94、7.76、21.82、5.85、10.96、11.47,均P＜0.05）.与AGEs组相比,在AGEs处理时给予PKCβ抑制剂LY333531或PKA激活剂8-Br-cAMP,均可降低HIMVEC上P选择素、E选择素和VCAM-1的表达水平（=7.60、6.60、6.25、11.58、4.08、3.47,均P＜0.05）,并减少白细胞的黏附（t=7.67、8.89,均P＜0.05）.结论 AGEs通过RAGE受体上调PKCβ和下调PKA增加HIMVEC上黏附分子的表达,促进白细胞的黏附,可能是糖尿病状态下胰岛中白细胞浸润的机制之一.     

1-磷酸鞘氨醇受体1参与晚期糖基化终产物引起的血管平滑肌细胞增殖和迁移

目的观察1-磷酸鞘氨醇受体1(S1PR1)在晚期糖基化终产物(AGE)引起的血管平滑肌细胞增殖和迁移中的作用。方法培养人脐动脉平滑肌细胞(HUASMC),葡萄糖与牛血清白蛋白(BSA)孵育法获得AGE-BSA,分为对照组、BSA组和AGE-BSA组,采用CCK-8实验检测平滑肌细胞增殖能力,采用细胞划痕和Transwell实验检测平滑肌细胞迁移能力,并进一步观察BSA和AGE-BSA在有或无S1PR1拮抗剂VPC23019/激动剂SEW2871预处理后的细胞增殖和迁移。结果与对照组比较,BSA和AGE-BSA均能诱导HUASMC增殖和迁移,AGE-BSA的作用比BSA更加显著(P0.05);S1PR1拮抗剂VPC23019可以明显抑制BSA和AGE-BSA诱导的HUASMC增殖和迁移;S1PR1激动剂SEW2871本身就可以促进HUASMC增殖和迁移,并且进一步促进BSA诱导的HUASMC增殖和迁移,而对AGE-BSA诱导的HUASMC增殖和迁移没有进一步的促进作用。结论血浆白蛋白本身对平滑肌细胞的增殖具有促进作用,糖基化修饰的白蛋白这一作用更加明显;S1PR1的激活参与了BSA和AGE-BSA促进平滑肌细胞增殖和迁移,AGE-BSA对S1PR1的激活作用更加显著。     

血红素加氧酶1在高糖和糖基化终产物致人单核细胞氧化应激中的作用

目的探讨血红素加氧酶1（HO-1）高表达在对抗高糖和糖基化终产物（AGEs）诱导的人单核细胞（THP-1）氧化应激中的作用。方法THP-1细胞分为对照（NC）组、GLU＋AGEs组、钴原卟啉（CoPP）＋GLU4-AGEs组和CoPP组4组,孵育24h后收集细胞及培养液上清,检测各组细胞的活性氧（ROS）产量、培养液上清丙二醛（MDA）和肿瘤坏死因子α（TNF-α）水平及HO-1表达。结果GLU4-AGEs组的ROS产量、MDA和TNF-α水平均显著高于NC组（P〈0．05）;CoPP4-GLU4-AGEs组的ROS产量和MDA水平均显著低于GLU4-AGEs组（P〈0．05）。GLU4-AGES组的HO-1基因和蛋白表达均显著高于NC组（P％0．01）,CoPP4-GLU＋AGEs组的HO-1蛋白表达显著高于GLU4-AGEs组（P〈0．01）。结论CoPP通过诱导HO-1蛋白高表达拮抗高糖和AGEs导致的THP-1细胞氧化应激,通过诱导HO-1高表达可能拮抗糖尿病所致单核细胞氧化应激。     

Advanced glycation end products depress function of endothelial progenitor cells via p38 and ERK 1/2 mitogen-activated protein kinase pathways

Objective  Advanced glycation end products (AGEs) and endothelial progenitor cells (EPCs) play divergent roles in the process of atherosclerosis. We investigated the effects of AGE-human serum albumin (AGE-HSA) on receptor expression for AGEs (RAGE) and EPCs apoptosis. Methods  The human mononuclear cells were obtained by Ficoll density gradient centrifugation and cultured in M199 medium containing rh-VEGF (30 ng/ml), rh-b-FGF(6 ng/ml) and 20% NBCS for 8 days. The adhesive EPCs were sequentially harvested after 24 h synchronization and challenged with AGE-HSA (concentration range from 0 to 300 μg/ml) for 24 h and 200 μg/ml AGE-HSA (time range from 0 to 36 h). EPCs apoptosis and migration were determined, expressions of RAGE, phosphorylated ERK1/2, JNK and p38 mitogen-activated protein kinase (MAPK) of EPCs were quantified by fluorescent quantitation RT-PCR and Western-blot, effect of AGE-HSA on NF-κB activtiy was determined by EMSA (electrophoretic mobility shift assay) in the presence and absence of special MAPK pathways pathway inhibitors. Results  AGE-HSA upregulated the expression of RAGE, this effect could be significantly inhibited by p38 MAPK and ERK MAPK inhibitor, but not by JNK MAPK inhibitor. AGE-HSA also promoted EPCs apoptosis and inhibited EPCs migration and increased NF-κB activity, these effects could be significantly attenuated by the anti-RAGE neutralizing antibody as well as by p38 and ERK MAPK inhibitors. Conclusion  AGE-HSA could promote atherosclerosis by upregulating EPCs RAGE expressions and promoting EPCs apoptosis via p38, ERK MAPK pathways, activation of NF-κB might also play a role in this process. C. Sun and C. Liang contributed equally to this work. Returned for 1. Revision: 13 December 2007 1. Revision received: 20 February 2008 Returned for 2. Revision: 7 March 2008 2. Revision received: 9 June 2008     

Toxic action of advanced glycation end products on cultured retinal capillary pericytes and endothelial cells: relevance to diabetic retinopathy

Summary The toxic effects of advanced glycation end products (AGEs) on bovine retinal capillary pericytes (BRP) and endothelial cells (BREC) were studied. AGE-modified bovine serum albumin (AGE-BSA) was toxic to BRP. At a concentration of 500 μg/ml it reduced the BRP number to 48 ± 3 % (p < 0.05) of untreated controls, as determined by cell counting with haemocytometer. AGE-BSA was also toxic to bovine aortic endothelial cells (BAEC) reducing cell number to 84 ± 3.1 % of untreated controls. Under similar conditions, low concentrations (62.5 μg/ml) of AGE-BSA were mitogenic to BREC increasing the cell proliferation to 156 ± 11 % (p < 0.05) above that of untreated controls. At a higher dose of 500 μg/ml AGE-BSA decreased the proliferation of BREC to 85 ± 6 % of untreated controls. Immunoblot analysis demonstrated that BRP and BREC express the p60 AGE-receptor. Retinal capillary bed from the human also stained positively for the p60 AGE-receptor. Addition of 0.25 μg/ml of p60 AGE-receptor antibody was able to block the effects of AGE-BSA on BRP and BREC. The level of binding of [¹²⁵I]-labelled AGE-BSA to the cell surface was small but significant among the three cell types. There was also an increase in the internalized pool of radioligand in BRP and BREC but this was very much lower than in BAEC. In all the cell types the internalized pool of [¹²⁵I]-labelled AGE-BSA was much larger than the amount associated with the cell surface. Degradation products were not detected in the media over the 24-h incubation of the cells with [¹²⁵I]AGE-BSA. The binding of [¹²⁵I]-labelled AGE-BSA to the cell surface was prevented by the addition of p60 AGE-receptor. These results suggest that the interaction of AGE-modified proteins with the membrane-bound AGE-receptor may play an important role in the pathogenesis of diabetic retinopathy. [Diabetologia (1997) 40: 156–164] Received: 23 August 1996; and in revised form: 29 October 1996     

2型糖尿病高血压患者血浆内源性分泌型晚期糖基化终末产物受体和氧化应激的关系

探讨2型糖尿病高血压患者血浆内源性分泌型晚期糖基化终末产物受体(esRAGE)与氧化应激的关系.结果 显示2型糖尿病患者esRAGE与体重指数(BMI,r=-0.33)、舒张压(r=-0.38)、氧化应激均显著相关(均P相似文献   

异氟醚对大鼠脑内糖基化终末产物及氧化应激水平的影响

目的 研究异氟醚对老年大鼠脑组织高级糖基化终末产物(AGEs)及氧化应激水平的影响.方法 老年及成年SD雄性大鼠共32只,在安静无干扰环境中进行12 h/12 h光暗周期节律适应4 d后,随机分为老年对照组(N1组),老年异氟醚处理组(A1组),成年对照组(N2组),成年异氟醚处理组(A2组).异氟醚组均给予异氟醚吸入处理3 h,对照组在相同时间,安静环境呼吸空气3 h.免疫组织化学法测定大鼠海马AGEs水平变化,硫代巴比妥法(TBA)测定脑组织丙二醛(MDA)含量,黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活性.结果 与N2组比较,N1组大鼠脑内AGEs、 MDA基础水平较高,SOD活性低于N2组. 24 h后A1组海马AGEs水平较N1组及A2组明显升高(P＜0.01);A2组AGEs水平与N2组比较无显著变化(P＞0.05).A1组MDA含量为(10.35±0.62)nmol/mg,较N1组及A2组明显升高,而SOD活性降低(P＜0.01).A2组SOD活性为(104.45±11.26) U/mg,较N2组降低,而MDA活性较A2组升高(P＜0.05).结论 异氟醚处理可引起老年大鼠脑组织内AGEs增高及氧化应激水平进一步升高可能是老年术后认知功能紊乱的机制之一.     

Effect of advanced glycation end products on oxidative stress in endothelial cells in culture: a warning on the use of cells studied in serum-free media

Aims/hypothesis: Alterations in vascular permeability and oxidative stress are characteristics of endothelial dysfunction in diabetic vascular disease. Since AGE-proteins have been hypothesized to mediate these effects, we studied the effects of AGE-bovine serum albumin on endothelial monolayer permeability and intracellular glutathione. Methods: AGE-BSA was prepared by incubating BSA for 30 days at 37 °C with 0.5 mol/l glucose and 0.2 mol/l phosphate buffer, pH 7.4. Permeability to fluorescently labelled BSA was assessed in a bovine pulmonary artery endothelial cell monolayer preparation. Glutathione was measured by an enzymatic assay. Results: AGE-BSA concentrations greater than 3 to 4 μmol/l produced maximal increases in permeability (6–8 times basal) within 3 to 4 h of incubation with the cells. This effect persisted for at least 48 h. However, BSA incubated in the absence of glucose produced similar effects. Dialysis of the AGE-BSA showed that low molecular weight components contained the permeability-increasing activity. Phosphate buffer used to prepare the AGE-BSA, at concentrations equivalent to those present in phosphate-buffered saline and in the AGE preparation (∼ 5 mmol/l), produced similar permeability increases at equivalent incubation times. Metal chelators (0.5 mmol/l) or inclusion of fetal bovine serum (10–20 %) blocked these permeability increases. These increases in permeability were associated with a decrease in endothelial glutathione, both inhibited by 10 mmol/l N-acetylcysteine, and a loss of cell-to-cell and cell-to-matrix adhesion molecules. Conclusion/interpretation: Trace amounts of redox-active metal ions in biological buffers could induce oxidative stress and alterations in cellular functions attributed to AGE-proteins in vitro. It is important to use metal-free phosphate and bicarbonate buffers in studies on cell biology in vitro, especially in serum-free media. [Diabetologia (2001) 44: 1310–1317] Received: 8 March 2001 and in revised form: 31 May 2001     

糖基化终产物对正常人血小板内皮型一氧化氮合酶活性及其表达的影响

目的 通过观察糖基化终产物（AGEs)对血小板内皮型一氧化氮合酶（eNOS)活性及其表达的影响，探讨AGEs损伤血小板的机制。方法 健康成人6例，取外周静脉血，用凝胶色谱柱法收集纯化的血小板悬液，分别与三种浓度的AGEs(100μg/ml,200μg/ml，400μg/ml）孵充300min，部分血小板用位素二步色谱法测定血小板一氧化氮合酶（NOS）活性；部分血小板用免疫沉淀法制备经eNOS蛋白，蛋白印迹法检测eNOS蛋白表达水平，结果 AGEs明显抑制正常人血小板NOS纯化eNOS蛋白，蛋白印迹法检测eNOS蛋白表达水平。结果 AGEs明显抑制正常人血小板NOS活性且呈浓度依赖性。正常人血小板表达eNOS；AGEs干预30min不影响eNOS表达水平。结论 AGEs通过抑制血小板eNOS活性而激活血小板，这种作用不是通过降低血小板eNOS表达实现的。     

糖基化终末产物对ECV-304细胞ICAM-1及VCAM-1表达的影响

目的探讨糖基化终产物(AGEs)与其受体(RAGE)对ECV-304细胞上血管细胞黏附分子-(1ICAM-1)和细胞间黏附分子-(1VCAM-1)的影响,为研究AGEs在动脉粥样硬化发生发展中的作用提供实验依据。方法采用体外制备的糖基化终产物——糖基化的牛血清白蛋白(AGE-BSA)和反义RAGE寡核苷酸处理ECV-304细胞,通过流式细胞仪技术、Western印迹技术检测ECV-304细胞上ICAM-1、VCAM-1蛋白质的表达。结果AGEs处理ECV-304细胞后,可诱导ECV-304细胞上VCAM-1和ICAM-1的表达增加,且这种效应呈剂量依赖性。采用反义技术阻断RAGE的mRNA水平的翻译后,ECV-304细胞ICAM-1和VCAM-1的表达呈剂量依赖性降低。结论AGEs可通过与其膜受体RAGE的结合激活血管内皮细胞VCAM-1和ICAM-1的表达,这可能是AGEs促动脉粥样硬化发生发展的机制之一。     

糖化终末产物对MIN6细胞活力及活性氧(ROS)水平的影响

探讨糖化终末产物(AGE)对小鼠胰岛细胞株MIN6细胞活力及活性氧(ROS)水平的影响.制备BSA-AGE,用不同浓度AGE(100、200、400 mg/L)干预MIN6细胞不同时间后,MTF比色法检测细胞活力变化.以活性氧捕获剂双氢-乙酰乙酸二氯荧光黄(DCFH-DA)孵育细胞,通过流式细胞仪检测细胞内二氯荧光黄(DCF)的荧光强度而测得细胞内活性氧水平,并测定胰岛素分泌的变化.随着AGE浓度的升高和作用时间的延长,细胞活力明显下降(P＜0.05).经DCFH-DA孵育后流式细胞仪检测显示,AGE处理组细胞内DCF平均荧光强度较对照组明显升高(P＜0.05).胰岛素分泌量随着AGE浓度的增高和时间的延长,呈下降趋势(P＞0.05).提示BSA-AGE抑制MIN6活力,使细胞内活性氧生成增加,诱导MIN6细胞氧化应激.

Abstract：

To explore the effect of advanced glycation end-products(AGEs)on cell viability and level of reactive oxygen species(ROS)in MIN6 cells. After intervention of various concentrations(100,200, and 400 mg/L)of AGEs for some time, cell viability was detected by MTT assay. 2', 7'-dichlorofluorescein diacetate(DCFH-DA)was used as a reactive oxygen species capture agent. The fluorescent intensity of 2', 7'-dichlorofluorescein(DCF), which was the product of cellular oxidation of DCFH-DA, was detected by flow cytometry. The level of ROS and insulin secretion was thus measured. Viability of MIN6 cells was inhibited by AGEs in a dose and time dependent manner(P＜0.05).Intracellular fluorescent intensity of DCF was markedly elevated in the AGEs groups as compared with that in the control group(P＜0.05).Insulin secretion was decreased in the AGEs groups than that in the control group(P＞0.05). The results suggest that AGEs inhibit the viability and induce oxidative stress in MIN6 cells by overproduction of ROS.     

The relationship between accumulation of advanced glycation end products and expression of vascular endothelial growth factor in human diabetic retinas

Summary Both advanced glycation end products and vascular endothelial growth factor are believed to play a role in the pathogenesis of diabetic retinopathy. It is known that vascular endothelial growth factor causes retinal neovascularization and a breakdown of the blood-retinal barrier; how advanced glycation end products affect the retina, however, remains largely unclear. The substance N^e-(carboxymethyl)lysine is a major immunologic epitope, i. e. a dominant advanced glycation end products antigen. We generated an anti-N^e-(carboxymethyl)lysine antibody to investigate the relationship between the localization of advanced glycation end products and that of vascular endothelial growth factor in 27 human diabetic retinas by immunohistochemistry. Nine control retinas were also examined. In all 27 diabetic retinas, N^e-(carboxymethyl)lysine was located in the thickened vascular wall. In 19 of the 27 retinas, strand-shaped N^e-(carboxymethyl)lysine immunoreactivity was also observed around the vessels. In all 27 diabetic retinas, vascular endothelial growth factor revealed a distribution pattern similar to that of N^e-(carboxymethyl)lysine. Vascular endothelial growth factor was also located in the vascular wall and in the perivascular area. Neither N^e-(carboxymethyl)lysine nor vascular endothelial growth factor immunoreactivity was detected in the 9 control retinas. Vessels with positive immunoreactivity for N^e-(carboxymethyl)lysine and/or vascular endothelial growth factor were counted. A general association was noted between accumulation of N^e-(carboxymethyl)lysine and expression of vascular endothelial growth factor in the eyes with non-proliferative diabetic retinopathy (p < 0.01) and proliferative diabetic retinopathy (p < 0.05). [Diabetologia (1997) 40: 764–769] Received: 19 December 1996 and in revised form: 26 February 1997     

葡萄籽多酚对糖基化终产物诱导的内皮细胞组织因子表达的影响

目的观察葡萄籽多酚(GSP)对糖基化终产物(AGEs)诱导的人脐静脉内皮细胞(HUVEC)组织因子(TF)蛋白及其mRNA表达的抑制作用。方法牛血清白蛋白(BSA)与葡萄糖在体外共同孵育以制备糖基化终产物(AGE-BSA),将培养的HUVEC与不同浓度的GSP(5、15、25μg/ml)预孵育4 h,再加入200μg/ml AGE-BSA共同培养,分别用流式细胞仪测定TF蛋白表达,用逆转录PCR检测TF mRNA的表达,用激光共聚焦显微镜检测细胞内活性氧簇(ROS)的产生。结果HUVEC未受刺激时,细胞内活性氧簇(ROS)(0.83±0.23)产生较低,TF蛋白[(4.42±0.69)%]及mRNA(0.0020±0.0008)表达亦较低,而AGE-BSA刺激明显增强了细胞内ROS(3.12±0.31)产生和TF蛋白(42.28±5.80)%及其mRNA(0.2964±0.0403)表达,与空白对照组比较,差异有统计学意义(P<0.01)。不同浓度GSP预孵育则以剂量依赖性的方式显著抑制了AGE-BSA诱导的细胞内ROS[分别为(2.36±0.34)、(1.88±0.43)、(1.23±0.20)]产生,并下调了TF蛋白[分别为(28.45±2.19)%、(17.49±3.84)%、(8.54±1.57)%)]及其mRNA[分别为(0.0994±0.0231)、(0.0382±0.0073)、(0.0065±0.0010)]表达,P<0.01。结论GSP可能通过抑制细胞内氧化应激而影响AGEs诱导的内皮细胞TF生成,改善血管促凝血活性。