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。     

葡萄糖和晚期糖基化终产物联合刺激对人单核细胞血红素加氧酶1表达的影响

目的 探讨葡萄糖和晚期糖基化终产物(AGE)联合刺激对人单核细胞THP-1血红素加氧酶1(HO-1)表达的影响. 方法 分别以15mmol/L葡萄糖、100μg/ml AGE和二者联合刺激THP-1,比较各组活性氧(ROS)产量,培养液丙二醛(MDA)、肿瘤坏死因子α(TNFα)水平和细胞HO-1mRNA及蛋白的表达量. 结果葡萄糖和AGE联合刺激的ROS产量、MDA、TNFα水平及HO-1mRNA和蛋白表达均明显高于单独刺激组. 结论 葡萄糖和AGE联合刺激可导致THP-1细胞氧化应激和HO-1表达增加.     

晚期糖基化终末产物与骨质疏松症

骨质疏松的主要表现是低骨量和骨组织微结构退变,其发生的本质在于骨再造过程紊乱即骨吸收超过骨形成。骨吸收与骨形成分别与破骨细胞和成骨细胞的活动直接相关。目前研究发现众多激素、生长因子和细胞因子等参与均衡这两类细胞的数量和活性,影响骨代谢平衡,晚期糖基化终末产物也是目前其中研究较为广泛的因子之一。晚期糖基化终末产物随着年龄增长在体内积聚增多,通过直接或间接的作用导致骨代谢的失衡,出现骨质疏松。     

晚期糖基化终末产物及其受体对血管平滑肌细胞作用机制的研究

晚期糖基化终末产物(AGEs)是导致糖尿病心血管并发症的重要影响因素。经过深入研究和探讨,发现AGEs对血管平滑肌细胞(VSMC)的病理生理学作用是其中关键之一。在此过程中,AGEs与存在于VSMC膜表面的受体(RAGE)结合,导致了一系列促炎症和促血栓形成反应。了解其中机制并发现拮抗抑制剂,有助于指导我们临床的预防和治疗。本文就AGEs及RAGE对VSMC作用机制予以综述。     

晚期糖基化终末产物与纤维化

晚期糖基化终末产物形成增多是糖尿病的重要特征。目前多个研究显示，其在糖尿病并发症中的发生、发展起了重要作用。晚期糖基化终末产物能促进肾脏、血管、腹膜等组织纤维化。其促纤维化作用可通过直接修饰细胞外基质、促进细胞外基质分泌、促进致纤维化细胞因子的产生、促进间质细胞转化及抑制细胞外基质降解等环节实现。本文对晚期糖基化终末产物的促纤维化作用进行综述。     

晚期糖基化终末产物调节氧化应激对内皮祖细胞生物学功能的影响

目的 观察晚期糖基化终末产物对体外培养的内皮祖细胞氧化应激状况的改变及对内皮祖细胞生物学功能的影响,探讨晚期糖基化终末产物参与动脉粥样硬化发生发展的可能作用位点.方法 使用密度梯度离心法从骨髓获取单个核细胞并进行体外培养.对贴壁细胞进行细胞化学分析,以激光共聚焦显微镜鉴定FITC标记荆豆凝血素I和DiI-标记的乙酰化低密度脂蛋白双染色阳性细胞为正在分化的内皮祖细胞.在内皮祖细胞中加入不同浓度晚期糖基化终末产物,测定晚期糖基化终末产物作用24 h后内皮祖细胞内活性氧、超氧化物岐化酶、谷胱甘肽过氧化物酶含量,同时测定内皮祖细胞迁移、黏附和增殖能力.结果 随晚期糖基化终末产物作用浓度升高(0、50、100和200 mg/L),内皮祖细胞内活性氧含量明显增加(分别为2.78±0.12、5.98±0.11、6.42±0.12和7.39±0.09,P<0.01),超氧化物岐化酶(分别为100%、81.2%±3.1%、71.0%±3.1%和44.2%±3.3%,P<0.01)、谷胱甘肽过氧化物酶(分别为100%、80.4%±3.6%、68.6%±3.7%和40.6%±4.2%,P<0.01)等抗氧化酶mR-NA含量减少,活性减退(P<0.01),内皮祖细胞生物学功能明显减退(P<0.01).结论 晚期糖基化终末产物促进内皮祖细胞内活性氧生成,减少抗氧化酶的合成,增强氧化应激,破坏细胞内环境稳定性,使细胞生物学功能受损.并且这种变化与晚期糖基化终末产物浓度成正相关.     

晚期糖基化终末产物受体在疾病发展进程中的作用

<正>Toth等〔1,2〕首次在胎牛肺内皮细胞中发现晚期糖基化终末产物受体(RAGE),学者们开始关注RAGE在加剧糖尿病病理损伤过程中的作用。研究者〔1,3⁶〕发现RAGE除与糖尿病及其并发症关系密切外,还参与肿瘤生长、神经系统疾病、心血管疾病、炎性反应等多种病理生理过程。本文将RAGE在各类疾病中的作用做一综述。     

晚期糖基化终末产物受体在特发性肺纤维化中的研究进展

由于病因不明，特发性肺纤维化(idiopathic pulmonary fibrosis, IPF)缺乏有效的干预措施。晚期糖基化终末产物受体(receptor for advanced glycation end products, RAGE)是免疫球蛋白受体超家族的成员，在肺脏中表达最多，有助于维持肺组织的动态稳定。其参与糖尿病肾纤维化和肝纤维化已有证明，多项研究也表明，RAGE与IPF有关。本文就RAGE与IPF的研究进展做一综述，以期为IPF的治疗提供一思路。     

晚期糖基化终末产物与糖尿病神经病变

非酶糖基化反应是糖尿病神经病变的重要发病机制之一。持久高血糖使体内晚期糖基化终末产物（AGEs）不断积累,沉积于神经组织的AGEs不仅修饰了细胞骨架蛋白、髓鞘蛋白及基质蛋白等,从而直接损害神经结构与功能,而且还通过增强氧化应激反应,或与神经元表面AGEs受体（RAGE）作用进一步导致神经功能紊乱。AGEs还可引起神经微循环障碍。单用或联用AGEs抑制剂、抗氧化剂、可溶性RAGE及抗RAGE IgG在防止、缓解、逆转糖尿病神经病变中显示出巨大的潜力。     

晚期糖基化终末产物致动脉粥样硬化的机制

晚期糖基化终末产物(advanced glycation end products,AGE)是由还原糖的羰基与游离氨基反应形成的复合物。AGE通过与其受体(RAGE)结合,改变细胞内信号转导、诱导炎症、增强氧化应激;与胶原交联、修饰脂蛋白等损害血管的完整性;这些导致血管内皮细胞功能紊乱,刺激平滑肌细胞迁移增殖,启动及加速糖尿病动脉粥样硬化和血管并发症的发生发展。阻断AGE-RAGE系统对防治糖尿病并发症具有重要意义。     

改变血红素加氧酶-1水平对糖尿病大鼠氧化应激状态及肾功能的影响

目的 探讨血红素加氧酶-1(HO-1)对糖尿病(DM)大鼠氧化应激状态及肾功能的影响.方法 以链脲佐菌素诱导DM大鼠模型.SD大鼠分成4组:对照组、DM组、正铁血红素Hemin(HO-1)诱导剂组、ZnPP(HO-1抑制剂)组.检测血清总抗氧化能力(TAOC)、丙二醛(MDA)含量和尿白蛋白排泄率(UEA);RT-PCR法检测肾脏组织TNF-α和HO-1mRNA表达水平.结果 Hemin组血清总抗氧化能力与DM组相比明显增高;而给予ZnPP后DM大鼠MDA含量增加,总抗氧化能力降低;DM大鼠UEA上升(P均<0.01),并随病程延长而加重.Hemin组UEA与DM 5 w组相比已有下降趋势,但尚无统计学差异(P>0.05);ZnPP组大鼠UEA明显增高(P<0.01);与对照组相比,DM大鼠肾组织TNF-α及HO-1 mRNA表达增加;应用Hemin后DM大鼠肾脏组织TNF-α表达减少(P<0.01).结论提高DM大鼠肾脏HO-1表达水平可以改善肾组织氧化应激状态、延缓肾功能障碍.     

银杏叶提取物对肾间质成纤维细胞中AGEs诱导的TGF-β1CTGF表达及氧化应激的抑制作用

目的探讨银杏叶提取物(EGb)在培养的正常大鼠肾间质成纤维细胞系(NRK-49F)中对糖基化终产物(AGEs)诱导的转化生长因子-β1(TGF-β1)和结缔组织生长因子(CTGF)mRNA表达及氧化应激作用的影响。方法于2005-01～2005-07以同济大学附属东方医院肾内科选用NRK-49F细胞为对象,以单纯培养基和高糖培养基(葡萄糖浓度25mmol/L)作为对照,用含AGEs的低糖(葡萄糖浓度5.5mmol/L)或高糖(葡萄糖浓度25mmol/L)DMEM培养液培养24h;并用不同质量浓度EGb(50,100mg·mL-1)预处理细胞以观察EGb的干预作用。采用流式细胞仪检测细胞内活性氧水平,逆转录聚合酶链反应(RT-PCR)检测细胞TGF-β1和CTGFmRNA表达。结果与正常对照组相比,AGEs可显著增强NRK-49F细胞中TGF-β1和CTGFmRNA的表达和细胞内氧化水平,而与AGEs和高糖组分别相比,AGEs与高糖共同作用可使NRK-49F细胞中TGF-β1和CTGFmRNA的表达和细胞内氧化水平显著增加;银杏叶提取物预处理可抑制AGEs诱导的细胞内活性氧产生增加,同时阻断AGEs诱导的TGF-β1和CTGFmRNA表达上调。结论银杏叶提取物可能通过清除自由基,抑制氧化应激反应而拮抗肾间质成纤维细胞中AGEs诱导的TGF-β1和CTGFmRNA过表达,可能是EGb防治DN的作用机制之一。     

血红素加氧酶-1对糖尿病大鼠胸主动脉功能的影响

目的探讨血红素加氧酶-1（HO-1）对糖尿病（DM）大鼠大血管功能的影响。方法SD大鼠分为4组：对照组、DM组、hemin（HO-1诱导剂）＋DM组、锌原卟啉（ZnPP,HO-1抑制剂）＋DM组。RT-PCR法检测血管组织HO-1表达水平 应用离体血管张力检测技术观察胸主动脉血管的反应性 扫描电镜下观察血管内皮超微结构。结果hemin＋DM组HO-1mRNA水平是对照组的2.01倍。与DM组相比,hemin＋DM组血管环对乙酰胆碱（Ach）舒张百分率增高,对苯肾上腺素（PE）的收缩反应减弱,内皮细胞形态有所改善 而ZnPP＋DM组大鼠对Ach的舒张反应继续下降,内皮细胞破坏严重。结论提高HO-1的表达水平有益于改善DM大鼠大血管反应性失调。     

1,2,3,4,6-penta-O-galloyl-β-D-glucose up-regulates heme oxygenase-1 expression by stimulating Nrf2 nuclear translocation in an extracellular signal-regulated kinase-dependent manner in HepG2 cells

AIM: To examine the potency of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG) as a hepatic heme oxygenase-1 (HO-1) inducer and its regulation in HepG2 cells.METHODS: Expression of HO-1 and NF-E2-related factor 2 (Nrf2) and activation of mitogen-activated protein (MAP) kinases were analyzed by Western blot, immunofluorescence assay, and flow cytometry. Transfections of HO-1 gene, small interfering RNAs for HO-1 and Nrf2,and dominant-negative gene for MAP/extracellular signalregulated kinase (ERK) were carried out to dissect the signaling pathways leading to HO-1 expression in HepG 2 cells.RESULTS: PGG up-regulated HO-1 expression and this expression conferred cytoprotection against oxidative injury induced by t-butyl hydroperoxide. Moreover, PGG induced Nrf2 nuclear translocation, which was found to be an upstream step of PGG-induced HO-1 expression, and ERK activation, of which pathway was involved in PGG-induced Nrf2 nuclear translocation, HO-1 expression and cytoprotection.CONCLUSION: PGG up-regulates HO-1 expression by stimulating Nrf2 nuclear translocation in an ERK-dependent manner, and HO-1 expression by PGG may serve as one of the important mechanisms for its hepatoprotective effects.     

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.     

Induction of HO-1 and redox signaling in endothelial cells by advanced glycation end products: A role for Nrf2 in vascular protection in diabetes

Background and aims

Hyperglycemia and diabetes are associated with increased formation of advanced glycation end products and enhanced oxidative stress, leading to the progression of diabetic vascular disease. We have investigated the mechanisms by which AGE-modified bovine albumin (AGE-BSA) induces reactive oxygen species (ROS) generation, leading to nuclear factor-erythroid 2-related factor (Nrf2) dependent induction of the antioxidant genes heme oxygenase-1 (HO-1) and NADPH:quinone oxidoreductase 1 (NQO1) in bovine aortic endothelial cells.

Methods and results

AGE-BSA (100 μg ml⁻¹, 0-24 h), but not native BSA, elicited time-dependent increases in ROS generation, Nrf2 nuclear translocation and enhanced mRNA and protein expression of HO-1 and NQO1, but not glutathione peroxidase-1. Inhibition of ROS production with the superoxide scavenger Tiron or inhibitors of flavoproteins (diphenylene iodonium) and NADPH oxidase (apocynin), but not eNOS (l-NAME) or mitochondria complex I (rotenone) abrogated HO-1 induction by AGE-BSA. Although AGE-BSA induced rapid phosphorylation of JNK and Akt, only inhibition of JNK abrogated HO-1 expression, implicating the involvement of the JNK signaling pathway in AGEs activation of Nrf2/ARE-linked antioxidant gene expression.

Conclusion

Our findings establish that AGEs activate redox sensitive Nrf2-dependent antioxidant gene expression in bovine aortic endothelial cells, providing an adaptive endogenous defense against oxidative stress in diabetes.     

Effect of heme oxygenase-1 on renal function in rats with liver cirrhosis

AIM: To investigate the role of heme oxygenase-1 (HO-1) in pathogenesis of experimental hepatorenal syndrome (HRS). METHODS: Rats were divided into liver cirrhotic group, zinc protoporphyrin IX (ZnPP) treatment group, cobalt protoporphyrin (CoPP) treatment group and sham group. Biliary cirrhosis was established by bile duct ligation in the first three groups. Rats in the ZnPP and CoPP treatment groups received intraperitoneal injection of ZnPP and CoPP, respectively, 24 h before sample collection. Expressio...