温筋通对糖尿病大鼠心血管组织糖基化终产物的形成及其受体和ICAM-1表达的影响

目的:研究中药复方温筋通(WJT)对糖尿病大鼠心血管糖基化终产物(AGEs)的形成以及AGEs受体(RAGE)和细胞间粘附因子-1(ICAM-1)表达的影响。方法:用链脲佐菌素复制糖尿病大鼠模型。采用荧光法、RT-PCR和原位杂交的方法对心血管组织AGEs的沉积以及RAGE和ICAM-1的表达进行检测。结果:WJT治疗组AGEs形成量明显低于糖尿病模型组(P＜0.01),其治疗作用与AG相当;RAGE和ICAM-1主要在内皮细胞表达,其表达量与AGEs的沉积量呈明显正相关(P＜0.01)。结论:WJT可明显降低糖尿病大鼠主动脉和心肌组织AGEs的形成量以及RAGE和ICAM-1的表达。     

糖基化终产物和高糖对小牛主动脉血管细胞的损伤作用

目的研究糖基化终产物（AGEs）和高浓度葡萄糖对血管细胞的损伤及对其糖基化终产物受体（RAGE）表达的影响。方法分别用10g/L糖基化终产物、10mol／L葡萄糖和两者的混合作用于牛主动脉血管细胞，利用生化方法测定细胞乳酸脱氢酶（IDH）、还原型谷胱甘肽（GSH）和NO2^-／NO3^-的含量，用MTT法测定细胞的活性。用CELL-ELISA和RT-PCR检测细胞RAGE的表达。结果与正常组（C）相比，高糖组（G）、AGEs组（A）和联合损伤组（G＋A）对主动脉内皮细胞的生长有明显的抑制作用（P〈0．01）和对平滑肌细胞的生长有明显的促进作用，主动脉血管细胞LDH的泄漏量明显增高，GSH和NO2^-／NO3^-的含量明显减少（P〈0．01）；且在的作用最强。同时，联合损伤组血管细胞的RAGE表达水平明显高于AGEs组和高糖组。结论AGEs比高浓度葡萄糖更具损伤血管细胞的作用，且AGEs与高糖联合作用对细胞的损伤最为明显，这种联合损伤的过程也是通过RAGE介导的。联合损伤组     

糖基化终产物在糖尿病大鼠心肌病变中的作用

目的观察糖尿病心肌病变过程中心肌组织糖基化终产物（advanced glycosylation endproducts,AGEs）的变化,探讨AGEs对糖尿病大鼠心肌的影响。方法建立糖尿病大鼠模型,随机分为对照组（CON）、糖尿病组（DM）和氨基胍治疗组（AG）,饲养12周。分别测定各组大鼠血糖、血清LDH、CK活性、心脏重量指数、血清果糖胺（FMN）及AGEs含量、电镜观察心肌超微结构。结果DM组大鼠血糖、血清LDH、CK活性、心脏重量指数、血清果糖胺（FMN）及AGEs含量明显高于CON组。超微结构显示心肌肌原纤维排列紊乱,间质胶原增生,微血管基底膜增厚,管腔狭窄。AG组大鼠血清LDH、CK活性、心脏重量指数、血清果糖胺（FMN）及AGEs含量明显降低。微血管基底膜增厚减轻,问质胶原减少,心肌细胞超微结构异常减轻。结论AGEs在糖尿病心肌改变的发生中起重要作用。     

糖尿病大鼠腹主动脉零应力状态

目的：通过腹主动脉零应力状态的研究，探讨糖尿病，高血压大鼠血管力学特性重建的规律。方法：用链脲佐菌素（STZ）分别诱导SD和自发性高血压大鼠（SHR），建立伴有高血压的糖尿病（SHRDM）和不伴有高血压的糖尿病（SDDM）动物模型，利用生物显微镜和图像分析系统对其腹主动脉张开角进行观测。结果：（1）SD组大鼠主动脉张开角在病程1周到4周加大，其后缓慢减小，8周后趋于平衡。（2）SDDM组大鼠主动脉张开角1－4周急剧升高，4－8周急剧降低，16周后又急剧升高，8周，16周时SDDM小于SD（P＜0．05），4周和24周时SDDM大于SD（P＜0．01），（3）SHR张开角的变化趋势恰与SDDM相反，且在1周，8周，16周时大于SD（P＜0．01），而4周又小于SD（P＜0．05）。（4）SHRDM张开角的变化与SDDM趋势相似，但4周时小于SDDM（P＜0．01），8，16周时大于SDDM（P＜0．05），结论：糖尿病，高血压大鼠主动脉壁零应力状态异常，在病程早期两者的变化趋势相反，提示高血压和糖尿病大血管壁均存在明显的不均匀生长，但是不均匀性生长的方式不同。     

糖基化终产物对人单核细胞源树突状细胞糖基化终产物受体表达的研究

目的：探讨糖基化终产物 (AGEs）)对人单核细胞源树突状细胞（MDCs）糖基化终产物受体（RAGE） 表达的影响。 方法： 用免疫磁珠分离人外周血CD14+单核细胞，经含rhGM-CSF（100 μg/L）和rhIL-4（50 μg/L）的RPMI-1640培养，使其分化为MDCs，采用RT-PCR和Western blotting法，观察糖基化-白蛋白（AGE-BSA）对MDCs RAGE mRNA和蛋白表达的影响，同时检测培养液上清中IFN-γ和IL-12的浓度。 结果： AGE-BSA诱导DCs RAGE mRNA和蛋白的表达（P＜0.05），高于空白对照组，并且明显促进了DCs IFN-γ和IL-12的分泌（P＜0.05）。BSA干预组与空白对照组相比差异无显著（P＞0.05）。 结论： AGEs能够上调DCs RAGE的表达，并且促进了DCs IFN-γ和IL-12的分泌，这可能是糖尿病通过DCs促进动脉粥样硬化发生的重要机制之一。     

糖基化终末产物对大鼠肾系膜细胞纤溶酶原激活物抑制物-1表达韵影响

目的：观察糖基化终末产物（AGEs）对大鼠肾系膜细胞纤溶酶原激活物抑制物-1（PAI-1）表达的影响及其与细胞外基质（ECM）成分含量的关系。方法：体外培养正常大鼠肾系膜细胞，分别用糖化牛血清白蛋白（AGEs）及未经糖化的牛血清白蛋白（BSA）处理，以常规培养的肾系膜细胞作为对照，检测不同时间、不同浓度AGEs对纤维连接蛋白（FN）、Ⅳ型胶原、PAI-1表达的影响。MTT法检测AGEs对系膜细胞增殖的作用，ELISA测定条件培养基中FN、Ⅳ型胶原及PAI-1蛋白含量，逆转录聚合酶链式反应（RT—PCR）检测系膜细胞PAI-1 mRNA的表达。结果：与相应浓度的BSA比较，AGEs（0—200mg／L）对系膜细胞增殖无明显影响，但可不同程度地刺激系膜细胞FN、Ⅳ型胶原、PAI-1蛋白的产生。RT—PCR检测显示，给予AGEs（100mg／L）的系膜细胞PAI-1 mRNA的表达明显增加（P〈0．01）。结论：AGEs促进系膜细胞PAI—1的表达，提示AGEs通过上调PAI-1的表达而减少细胞外基质降解，可能是糖尿病肾病细胞外基质积聚的原因之一。     

糖基化终产物与糖尿病血管并发症

糖尿病时糖基化终产物(advanced glycation end products,AGEs)生成与蓄积不仅加速糖尿病本身的发展,还与糖尿病肾病、视网膜病、神经性疾病和心血管疾病等慢性并发症密切相关。AGEs与糖基化终产物受体(receptor for advanced glycation end products,RAGE)相互作用诱导氧化应激,促进炎症反应,影响凝血系统,在糖尿病及其并发症的病理生理过程中起重要作用。抑制AGEs生成、交联结构及阻断AGEs与RAGE相互作用为寻找治疗糖尿病血管并发症的药物提供了新的途径。     

钙化大鼠主动脉钙调神经磷酸酶的表达及活性

目的探讨钙调神经磷酸酶是否参与血管钙化的调节过程。方法4周龄SD雄性大鼠36只,随机分为对照组、钙化组和环孢霉素A组,每组12只。采用华法林和维生素D,建立大鼠主动脉钙化模型,免疫组织化学方法测定主动脉组织钙调神经磷酸酶蛋白,比色法测定组织钙调神经磷酸酶活性,比较各组间钙调神经磷酸酶蛋白表达及活性是否有差别。结果钙化组大鼠主动脉钙调神经磷酸酶蛋白表达较对照组明显增加（P〈0．01）,钙化组大鼠主动脉钙调神经磷酸酶活性较对照组明显增强（P〈0．01）;环孢霉素A组大鼠主动脉钙调神经磷酸酶蛋白表达较对照组明显增加（P〈0．01）,较钙化组表达减少（P〈0．05）,环孢霉素A组大鼠主动脉钙调神经磷酸酶活性较对照组明显增加（P〈0．01）,与钙化组比较无显著性差异（P〉0．05）。结论钙调神经磷酸酶很可能参与血管钙化的调节过程。     

糖基化终产物通过其受体诱导人肾小球系膜细胞表达CTGF和FN

目的： 探讨体外培养条件下糖基化终产物（AGEs）对人肾小球系膜细胞(HRMCs）中结缔组织生长因子（CTGF）及纤维连接蛋白（FN）基因表达的影响及其可能的作用机制。方法: 将HRMCs与不同浓度的糖化牛血清白蛋白（AGE-BSA）和牛血清白蛋白（BSA）共同培养,或与同一质量浓度的AGE-BSA和BSA共同培养不同时间,以中和性抗RAGE抗体封闭细胞膜上糖基化终末产物受体（RAGE）;采用免疫印迹法（Western blotting）观察AGEs对HRMCs中RAGE表达的影响,半定量逆转录-聚合酶链反应（RT-PCR）法检测CTGF、FN mRNA的表达。结果: 在HRMCs中存在少量RAGE的表达,AGE-BSA能够诱导HRMCs中RAGE的表达增加,并以时间和剂量依赖方式促进HRMCs中CTGF和FN的表达上调;CTGF、FN的表达水平在加入不同浓度（50、100、200、400 mg/L）的AGE-BSA 作用48 h后以及加入质量浓度为200 mg/L的 AGE-BSA 作用不同时间（12、24、48、72h）后,较相应质量浓度或时间的BSA组和空白对照组均明显升高（P＜0.05）;抗RAGE抗体干预后能够部分抑制AGE-BSA诱导CTGF及FN的表达,而人IgG没有这种作用。结论: AGEs可能通过RAGE诱导CTGF及FN的表达上调,是糖尿病肾病肾脏纤维化的可能机制。     

皮肤AGEs荧光检测对糖尿病肾病的临床意义

目的 探讨皮肤AGEs荧光检测对糖尿病肾病的早期诊断价值及与糖尿病肾病分期相关性的临床意义。方法 将我院住院的122例糖尿病患者按尿白蛋白/肌酐比值,眼底检查及CKD分期分为单纯糖尿病组（DM0组）42例、糖尿病肾病eGFR≥45 ml/（min·1.73 m2）组（DKD1组）49例和糖尿病肾病eGFR＜45 ml/（min/1.73·m2）组（DKD2组）31例,选取同期行肾穿刺肾功能正常的非糖尿病患者51例为对照组（NC组）,分别检测各组皮肤AGEs、血白蛋白、尿微量白蛋白等指标。结果 ①糖尿病患者的皮肤AGEs、SBP、SCr、TG、TC均高于对照组,ALB、HB低于对照组,差异均有统计学意义（P＜0.05）;②与DMO组比较,DKD1组和DKD2组的SBP、肌酐、UA、24hUP、尿微量白蛋白、皮肤AGEs水平均升高,且DKD2组高于DKD1组,差异有统计学意义（P＜0.05);而TP、ALB、HB水平均降低,且DKD2组低于DKD1组,差异有统计学意义（P＜0.05）;③糖尿病患者皮肤AGEs水平与尿微量白蛋白水平呈正相关（r=0.484,P＜0.05）。④皮肤AGEs是糖尿病肾病相关的危险因素[OR=1.113,95%CI（1.055,1.174）]。⑤ROC曲线分析显示皮肤AGEs检测糖尿病肾病的敏感性为68.75%,特异性为71.43%。结论 AGEs可能参与糖尿病肾病发生发展,荧光检测皮肤AGEs可用于早期筛查DKD并且评估其病变程度。     

Pitavastatin attenuates AGEs-induced mitophagy via inhibition of ROS generation in the mitochondria of cardiomyocytes

This study aimed to investigate whether pitavastatin protected against injury induced by advanced glycation end products products (AGEs) in neonatal rat cardiomyocytes, and to examine the underlying mechanisms. Cardiomyocytes of neonatal rats were incubated for 48 hours with AGEs (100 mg/mL), receptor for advanced glycation end products (RAGE), antibody (1 mg/mL) and pitavastatin (600 ng/mL). The levels of p62 and beclin1 were determined by Western blotting. Mitochondrial membrane potential (DYm) and the generation of reactive oxygen species (ROS) were measured through the JC-1 and DCFH-DA. In the AGEs group, the expression of beclin1 was remarkably increased compared to the control group, while the expression of p62 was significantly decreased. AGEs also markedly decreased DYm and significantly increased ROS compared with the control group. After treatment with RAGE antibody or pitavastatin, the level of beclin1 was markedly decreased compared with the AGEs group, but the level of p62 was remarkably increased. In the AGEs + RAGE antibody group and AGEs + pitavastatin group, DYm was significantly increased and ROS was remarkably decreased compared with the AGEs group. In conclusion, AGEs-RAGE may induce autophagy of cardiomyocytes by generation of ROS and pitavastatin could protect against AGEs-induced injury against cardiomyocytes.     

Advanced glycation end‐products induce skeletal muscle atrophy and dysfunction in diabetic mice via a RAGE‐mediated,AMPK‐down‐regulated,Akt pathway

Diabetic myopathy, a less studied complication of diabetes, exhibits the clinical observations characterized by a less muscle mass, muscle weakness and a reduced physical functional capacity. Accumulation of advanced glycation end‐products (AGEs), known to play a role in diabetic complications, has been identified in ageing human skeletal muscles. However, the role of AGEs in diabetic myopathy remains unclear. Here, we investigated the effects of AGEs on myogenic differentiation and muscle atrophy in vivo and in vitro. We also evaluated the therapeutic potential of alagebrium chloride (Ala‐Cl), an inhibitor of AGEs. Muscle fibre atrophy and immunoreactivity for AGEs, Atrogin‐1 (a muscle atrophy marker) and phosphorylated AMP‐activated protein kinase (AMPK) expressions were markedly increased in human skeletal muscles from patients with diabetes as compared with control subjects. Moreover, in diabetic mice we found increased blood AGEs, less muscle mass, lower muscular endurance, atrophic muscle size and poor regenerative capacity, and increased levels of muscle AGE and receptor for AGE (RAGE), Atrogin‐1 and phosphorylated AMPK, which could be significantly ameliorated by Ala‐Cl. Furthermore, in vitro, AGEs (in a dose‐dependent manner) reduced myotube diameters (myotube atrophy) and induced Atrogin‐1 protein expression in myotubes differentiated from both mouse myoblasts and primary human skeletal muscle‐derived progenitor cells. AGEs exerted a negative regulation of myogenesis of mouse and human myoblasts. Ala‐Cl significantly inhibited the effects of AGEs on myotube atrophy and myogenesis. We further demonstrated that AGEs induced muscle atrophy/myogenesis impairment via a RAGE‐mediated AMPK‐down‐regulation of the Akt signalling pathway. Our findings support that AGEs play an important role in diabetic myopathy, and that an inhibitor of AGEs may offer a therapeutic strategy for managing the dysfunction of muscle due to diabetes or ageing. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Advanced glycation end-products and receptor for advanced glycation end-products expression in patients with idiopathic pulmonary fibrosis and NSIP

Advanced glycation end products (AGEs) are associated with the pathogenesis of various diseases. AGEs induce excess accumulation of extracellular matrix and expression of profibrotic cytokines. In addition, studies on receptor for advanced glycation end products (RAGE) have shown that the ligand-RAGE interaction activates several intracellular signaling cascades associated with several fibrotic diseases. We investigated the expression of AGEs and RAGE in samples from patients with idiopathic pulmonary fibrosis (IPF) and non-specific interstitial pneumonia (NSIP). Lung tissues and plasma samples from patients with IPF (n=10), NSIP (n=10), and control subjects (n=10) were obtained. Expression of AGEs and RAGE was determined by immunofluorescence assay of lung tissue. Circulating AGEs were measured by Western blot and enzyme-linked immunosorbent assay. Lungs with IPF showed strong expression for both AGEs and RAGE compared to that in NSIP and controls. However, no difference in AGE or RAGE expression was observed in lungs with NSIP compared to that in the controls. Levels of circulating AGEs also increased significantly in lungs of patients with IPF compared to those with NSIP and normal control. Increased AGE-RAGE interaction may play an important role in the pathogenesis of IPF.     

阿魏酸钠抑制糖尿病大鼠心肌非酶糖基化的形成

目的探讨阿魏酸钠(SF)对糖尿病(DM)大鼠心肌非酶糖基化的影响。方法对链脲佐菌素(STZ)诱导的DM大鼠灌胃给予SF110mg/(kg.d)治疗8周,测定各组大鼠血清超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及血清果糖胺(FMN)、丙二醛(MDA)水平,并用酶免法测定心肌糖基化终产物(AGEs)含量。结果DM大鼠心肌AGEs及血清FMN、MDA显著高于对照组,血清SOD、CAT活性降低,SF治疗显著改善上述指标的变化。结论SF可显著抑制DM大鼠心肌AGEs的形成,机制与其保护抗氧化酶有关。     

梓醇抑制AGEs诱导的EA.hy926细胞炎症反应及RAGE表达

目的:研究梓醇对晚期糖基化终产物(AGEs)诱导的EA.hy926内皮细胞炎症反应的抑制作用并探讨其可能机制。方法:将常规培养的EA.hy926细胞随机分为对照组、梓醇对照组、AGEs组以及梓醇高剂量(0.5 mmol/L)、中剂量(0.25 mmol/L)和低剂量(0.05 mmol/L)保护组。激光共聚焦显微镜观察细胞内活性氧簇(ROS)的生成;RT-PCR和Western blot检测细胞中单核细胞趋化蛋白1(MCP-1)、肿瘤坏死因子α(TNF-α)、血管细胞黏附分子1(VCAM-1)及晚期糖基化终产物受体(RAGE)的mRNA及蛋白的表达。结果:梓醇保护组ROS生成均明显减少,MCP-1、TNF-α和VCAM-1的mRNA及蛋白表达均显著降低,RAGE蛋白表达明显受抑制,且呈剂量依赖性(P0.05)。结论:梓醇能够有效抑制AGEs诱导的EA.hy926细胞内氧化应激,减轻炎症反应,其机制可能与其降低RAGE表达有关。     

Glycation Endproducts, Soluble Receptor for Advanced Glycation Endproducts and Cytokines in Diabetic and Non-diabetic Pregnancies

Problem  Cytokines, advanced glycation end products (AGEs), and their receptor RAGE have been recently suggested to play a role in human pregnancy. In this study, we sought to determine the alterations of plasma AGEs, soluble RAGE (sRAGE), and proinflammatory cytokines in normal pregnancies and those complicated with type 1 diabetes mellitus.
Method of study  These parameters were measured in samples from healthy non-pregnant (C), diabetic non-pregnant (D), healthy pregnant (HP), and pregnant diabetic (DP) women.
Results  In the first trimester, DP showed lower sRAGE and higher AGEs compared to HP. In the DP group, significant negative correlations were seen between TNF-α and lipopolysaccharide (LPS)-stimulated ΙL-6 in the first trimester and sRAGE in the third trimester. LPS-stimulated IL-12 was positively correlated with levels of AGEs in the third trimester.
Conclusion  We detected several differences in the levels of AGEs, sRAGE, and proinflammatory cytokines between euglycemic and diabetic pregnancies.     

The advanced glycation end‐product Nϵ‐carboxymethyllysine promotes progression of pancreatic cancer: implications for diabetes‐associated risk and its prevention

Diabetes is an established risk factor for pancreatic cancer (PaC), together with obesity, a Western diet, and tobacco smoking. The common mechanistic link might be the accumulation of advanced glycation end‐products (AGEs), which characterizes all of the above disease conditions and unhealthy habits. Surprisingly, however, the role of AGEs in PaC has not been examined yet, despite the evidence of a tumour‐promoting role of receptor for advanced glycation end‐products (RAGE), the receptor for AGEs. Here, we tested the hypothesis that AGEs promote PaC through RAGE activation. To this end, we investigated the effects of the AGE N^?‐carboxymethyllysine (CML) in human pancreatic ductal adenocarcinoma (PDA) cell lines and in a mouse model of Kras‐driven PaC interbred with a bioluminescent model of proliferation. Tumour growth was monitored in vivo by bioluminescence imaging and confirmed by histology. CML promoted PDA cell growth and RAGE expression, in a concentration‐dependent and time‐dependent manner, and activated downstream tumourigenic signalling pathways. These effects were counteracted by RAGE antagonist peptide (RAP). Exogenous AGE administration to PaC‐prone mice induced RAGE upregulation in pancreatic intraepithelial neoplasias (PanINs) and markedly accelerated progression to invasive PaC. At 11 weeks of age (6 weeks of CML treatment), PaC was observed in eight of 11 (72.7%) CML‐treated versus one of 11 (9.1%) vehicle‐treated [control (Ctr)] mice. RAP delayed PanIN development in Ctr mice but failed to prevent PaC promotion in CML‐treated mice, probably because of competition with soluble RAGE for binding to AGEs and/or compensatory upregulation of the RAGE homologue CD166/ activated leukocyte cell adhesion molecule, which also favoured tumour spread. These findings indicate that AGEs modulate the development and progression of PaC through receptor‐mediated mechanisms, and might be responsible for the additional risk conferred by diabetes and other conditions characterized by increased AGE accumulation. Finally, our data suggest that an AGE reduction strategy, instead of RAGE inhibition, might be suitable for the risk management and prevention of PaC. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.