α-硫辛酸对2型糖尿病大鼠大脑皮质的保护作用

目的探讨α-硫辛酸对2型糖尿病(T2DM)大鼠大脑皮质的保护作用及机制。方法 SD大鼠随机分为5组:对照组、糖尿病模型组、α-硫辛酸低、中、高剂量组。对照组大鼠给予普通饮食1个月后腹腔注射等体积的不含链脲佐菌素(STZ)柠檬酸缓冲液,实验组大鼠给予高脂高糖饮食1个月后腹腔注射小剂量的STZ 30 mg/kg,建立T2DM模型。α-硫辛酸低、中、高剂量组分别按15、30、60 mg/kg灌胃12 w。检测血糖和糖化血红蛋白、糖基化终末产物(AGEs)等血清指标;光镜下观察大脑皮质形态学变化;免疫组织化学法核因子(NF)-κB、胶质纤维酸性蛋白(GFAP)、糖基化终末产物受体(RAGE)的含量变化;Western印迹法测定NF-κB、RAGE的蛋白表达情况。结果与对照组比较,糖尿病模型组大鼠血糖值和血清糖化血红蛋白及AGEs含量明显增高(P<0.05),光镜下大鼠皮质神经元数目减少并出现退行性变,脑皮质中NF-κB、GFAP、RAGE蛋白表达显著增加(P<0.05);与糖尿病模型组比较,α-硫辛酸中剂量组血糖、血清糖化血红蛋白及AGEs含量明显降低(P<0.05),光镜下大鼠皮质神经元数目增多,病变有所改善,α-硫辛酸中剂量组NF-κB、GFAP、RAGE表达分别为2.26、160.12、2.87明显减少(P<0.05)。结论α-硫辛酸对糖尿病大鼠大脑皮质有保护作用,其机制可能与抑制血糖、糖化血红蛋白及血清中的AGEs,下调NF-κB、GFAP、RAGE的表达,改善大脑退行性病变有关。     

RAGE阻断剂FPS-ZM1对糖基化终末产物所致大鼠脑部炎症反应的影响及机制

目的探讨RAGE受体特异性阻断剂FPS-ZM1对糖基化终末产物(AGEs)所致大鼠脑部炎症反应及认知功能的影响。方法将40只大鼠随机分为四组:生理盐水组(NC组)FPS-ZM1对照组、AGEs组和FPS-ZM1组,采用脑立体定位技术,向AGEs组及FPS-ZM1组大鼠两侧海马注射AGEs 5μl,以制造动物损伤模型,用同样方法向NC组及FPS-ZM1对照组注射等量生理盐水,以制造模型对照;造模前1 w以1 mg·kg-1·d-1FPS-ZM1向FPS-ZM1组和FPS-ZM1对照组大鼠进行腹腔注射,并连续4 w给药,AGEs组、NC组则同时注射相同体积生理盐水,造模3 w后对各组大鼠进行Morris水迷宫实验,检测各组大鼠逃逸潜伏期(EL);用Elisa检测各组大鼠海马区Aβ1⁴0,Aβ140,Aβ1⁴2的水平;用Western印迹检测各组大鼠RAGE,p-NF-κB和肿瘤坏死因子(TNF)-α蛋白的表达;用免疫组织化学法检测各组大鼠海马区TNF-α蛋白的表达强度。结果 AGEs组与其他各组相比,EL显著延长(P<0.01),且Aβ142的水平;用Western印迹检测各组大鼠RAGE,p-NF-κB和肿瘤坏死因子(TNF)-α蛋白的表达;用免疫组织化学法检测各组大鼠海马区TNF-α蛋白的表达强度。结果 AGEs组与其他各组相比,EL显著延长(P<0.01),且Aβ1⁴0、Aβ140、Aβ1⁴2浓度均显著升高(P<0.01);同时AGEs组RAGE、p-NF-κB和TNF-α的蛋白表达明显增强(P<0.01);FPS-ZM1干预后上述各指标均明显低于AGEs组。结论 FPS-ZM1作为RAGE受体特异性阻断剂,能作用中枢系统减少Aβ142浓度均显著升高(P<0.01);同时AGEs组RAGE、p-NF-κB和TNF-α的蛋白表达明显增强(P<0.01);FPS-ZM1干预后上述各指标均明显低于AGEs组。结论 FPS-ZM1作为RAGE受体特异性阻断剂,能作用中枢系统减少Aβ1⁴0,生成从而提高AGEs脑损伤大鼠的智能,并通过抑制脑组织p-NF-κB上调,减轻脑AGEs损伤引起的炎性反应。该药因能透过血脑屏障有望成为抑制阿尔茨海默样病变的有效措施。     

糖基化终末产物上调大鼠心脏微血管内皮细胞NF-κB和COX-2表达

目的 研究糖基化终末产物(AGEs)对大鼠心脏微血管内皮细胞因子κB(NF-κB)和环氧合酶2(COX-2)表达的影响,探讨AGEs与糖尿病血管病变间的关系. 方法 体外培养大鼠心脏微血管内皮细胞至亚融和状态时,以不同浓度糖基化白蛋白BSA-AGEs与之作用不同时间后,检测内皮细胞NF-κB及COX-2蛋白的表达. 结果 25、50、100、200mg/L BSA-AGEs作用后,NF-κB和COX-2蛋白表达呈剂量依赖性增多,100mg/L AGEs作用6、12、24、48h,NF-κB和COX-2蛋白表达呈时间依赖性增多. 结论 BSA- AGEs可促进体外培养微血管内皮细胞NF-κB和COX-2的表达,其作用可能与NF-κB的活化有关.     

RAGE及其配体的临床意义研究进展

晚期糖基化终末产物(AGEs)受体(RAGE)是一种具有重要功能的多配体受体,其配体包括AGEs、两性素/高速泳动族盒1蛋白、S100/钙粒蛋白及β淀粉样肽等。RAGE属于单穿膜片段受体,为免疫球蛋白超家族的成员。有些RAGE缺少穿膜域,可由细胞分泌出来,成为可溶性RAGE(sRAGE)。位于细胞膜上的RAGE与相应的配体结合后可启动若干信号通路,其中以核因子-κB最为重要。RAGE不仅参与糖尿病慢性并发症的发生、发展,还与炎症反应、肿瘤的侵袭和转移、神经再生、Alzheimer病有关。用sRAGE或RAGE抗体可阻断RAGE的效应,具有潜在的治疗意义。     

老年脑梗死后血管性痴呆病人血清AGEs、RAGE水平与病情严重程度的关系

目的 探讨老年脑梗死后血管性痴呆(CI-VD)病人血清晚期糖基化终末产物(AGEs)、晚期糖基化终末产物受体(RAGE)水平与病情严重程度的关系。方法 选取2020年1月至2021年6月中国人民解放军中部战区总医院收治的96例老年CI-VD病人，另选取同期医院收治的84例老年单纯脑梗死(cerebral infarction, CI)病人，比较2组病人血清AGEs、RAGE水平。根据病情严重程度将老年CI-VD病人分为轻度组(n=25)、中度组(n=39)和重度组(n=32),比较3组病人血清AGEs、RAGE水平，采用Spearman秩相关分析血清AGEs、RAGE水平与病情严重程度的关系，采用Logistic回归分析老年CI-VD病人重度痴呆的影响因素，并采用ROC曲线分析血清AGEs、RAGE水平预测重度病情的价值。结果 老年CI-VD病人血清AGEs、RAGE水平均高于老年单纯CI病人(P<0.01);血清AGEs、RAGE水平随着病情的加重而增加(P<0.05),Spearman相关性分析显示，血清AGEs(r=0.446,P<0.001)、RAGE(r=0...     

吡哆胺对动脉粥样硬化兔晚期糖基化终末产物及其受体的影响

目的观察吡哆胺对动脉粥样硬化兔晚期糖基化终末产物(AGEs)及其受体的影响。方法利用高脂饮食法诱导建立兔动脉粥样硬化模型。将新西兰白兔按随机数字表法随机分为正常对照组、动脉硬化组、吡哆胺小剂量组和吡哆胺大剂量组。正常对照组给予普通食物;动脉硬化组给予高脂饮食;吡哆胺小剂量组给予高脂饮食+吡哆胺100 mg/(kg·d);吡哆胺大剂量组给予高脂饮食+吡哆胺150 mg/(kg·d),共观察12周。实验12周末监测所有兔血糖、三酰甘油、总胆固醇、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C);应用酶联免疫吸附试验法检测血清AGEs水平;观察主动脉病理形态学改变;免疫组化方法检测主动脉AGEs受体(RAGE)含量,并进行各组间的比较。结果实验12周末,(1)与对照组比较,动脉硬化组兔三酰甘油、总胆固醇、LDL-C、HDL-C均明显增高(均P0.01),血糖无明显变化(P0.05);动脉硬化组的血清AGEs水平[(419±29)mg/L)]、动脉RAGE吸光度(0.88±0.14)及斑块面积[(67.4±5.8)%]均较对照组[分别为(141±11)mg/L、(0.19±0.04)及0%]明显增高(均P0.01);(2)与动脉硬化组相比,吡哆胺小剂量组和吡哆胺大剂量组兔三酰甘油、总胆固醇、LDL-C、HDL-C、血糖均无明显变化(均P0.05);吡哆胺小剂量组的血清AGEs水平[(278±22)mg/L]、动脉RAGE吸光度(0.43±0.06)及斑块面积[(43.2±2.4)%]和吡哆胺大剂量组的血清AGEs水平[(211±18)mg/L]、动脉RAGE吸光度(0.27±0.05)及斑块面积[(27.4±2.8)%]均较动脉硬化组明显减少(均P0.01);(3)吡哆胺大剂量组的血清AGEs水平、动脉RAGE吸光度及斑块面积较吡哆胺小剂量组低(均P0.01)。(4)主动脉病理形态学:显微镜下见动脉硬化组动脉内膜增厚,形成明显的粥样斑块;有大量的泡沫细胞聚集及较多的炎性细胞。吡哆胺小剂量组和吡哆胺大剂量组较动脉硬化组均有不同程度的减轻。结论吡哆胺能够抑制、减缓实验性高脂饮食兔的动脉粥样硬化形成,可抑制血清AGES的生成及动脉RAGE的表达。     

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。     

吡哆胺对血管紧张素Ⅱ诱导的自发性高血压大鼠血管平滑肌细胞增殖的影响

目的:探讨吡哆胺对血管紧张素Ⅱ( AngⅡ)诱导的自发性高血压大鼠血管平滑肌细胞(VSMCs)增殖的影响及其作用机制.方法:原代培养自发性高血压大鼠胸主动脉VSMCs,选3～4代处于对数生长期的细胞进行药物干预.以未加任何干预的自发性高血压大鼠VSMCs为对照组,以10-7 mol/L AngⅡ刺激作为AngⅡ组,以不同浓度(0.1 mmol/L、1.0 mmol/L、10.0 mmol/L)吡哆胺预处理作为吡哆胺组.采用四唑盐比色法检测吡哆胺对VSMCs增殖的影响,酶联免疫吸附法检测细胞上清液晚期糖基化终末产物(AGEs)水平,流式细胞仪分析细胞内活性氧簇(ROS)水平,实时荧光半定量PCR检测晚期糖基化终末产物受体(RAGE)、核因子κB( NFκB)P65、还原型烟酰胺腺嘌呤二核苷磷酸(NADPH)氧化酶P47phox的mRNA水平.结果:与对照组相比,Ang Ⅱ组促进细胞增殖(P＜0.01),升高细胞上清液中AGEs浓度(P＜0.01),使细胞内ROS生成增多(P＜0.01),胞内RAGE、NF-κB P65、NADPH氧化酶P47phox mRNA相对量的表达均较对照组显著升高(P＜0.01);1.0mmol/L和10.0 mmol/L吡哆胺预处理可以逆转AngⅡ作用下的细胞增殖(P＜0.01),降低细胞上清液中AGEs 浓度(P＜0.01),减少ROS生成(P＜0.01),使RAGE、NF-κB P65、NADPH氧化酶P47phoxmRNA表达下降(P＜0.01),且吡哆胺10 mmol/L作用比1 mmol/L更显著(P＜0.01).结论:毗哆胺可能通过抑制AGEs的形成、降低胞内ROS水平,减少RAGE、NF-κB P65、NADPH氧化酶P47phox表达,从而有效抑制AngⅡ诱导的VSMCs增殖作用.     

D-半乳糖诱导的衰老模型中RAGE和P21的表达和意义

目的探讨大鼠衰老模型中肝脏糖基化、氧化应激水平与糖基化终末产物受体(RAGE)、P21的蛋白表达之间的关系。方法建立衰老动物模型,荧光法检测肝脏高级糖基化终末产物(AGEs)含量,硫代巴比妥酸(TBA)法检测MDA含量,邻苯二甲醛(OPT)法检测GSH含量,western blot检测RAGE和P21表达水平。结果与对照组相比,模型组肝脏的AGEs和MDA含量显著升高,GSH含量显著降低;RAGE和P21蛋白表达水平显著升高。结论在D-半乳糖诱导的衰老模型中,氧化应激和糖基化水平的升高与RAGE和P21的高表达有关,认为RAGE介导的细胞反应促进了衰老过程。     

糖基化终末产物与糖尿病慢性并发症研究进展

<正>糖基化终末产物(AGEs)是蛋白质、脂肪酸和核酸等大分子物质的非酶糖基化产物,目前研究表明AGEs可直接或与其受体相互作用加速人体的衰老和导致糖尿病、阿尔茨海默病(AD)、动脉粥样硬化(AS)等慢性退化性疾病的发生和发展。AGEs与糖尿病慢性并发症的关系是目前研究热点,本文就此进行综述。1 AGEs及AGEs受体(RAGE)AGEs是一组在蛋白质、脂肪酸及核酸的氨基基团与还原     

糖尿病大鼠阴茎组织糖基化终产物含量的变化和糖基化终产物受体的表达情况

目的研究糖尿病阴茎组织糖基化终产物(AGEs)含量的变化和糖基化终产物受体(RAGE)的表达情况。方法用葡萄糖和血红蛋白(Hb)在体外孵育形成Hb-AGEs,免疫新西兰兔,制备AGEs抗血清,建立竞争性ELISA法,测定大鼠阴茎组织AGEs含量。应用RT-PCR研究RAGEmRNA表达。结果各组糖尿病大鼠未经治疗时阴茎组织AGEs水平均较对照(NC)组明显升高(P<0.01),8周时糖尿病用胰岛素治疗(DMI)组及糖尿病用胰岛素和二氨基酚嗪(DAP)治疗(DMID)组的AGEs水平较糖尿病未治疗(DM)组降低(P<0.05～0.01),至16周DMID组上述指标较DMI组明显降低(P<0.01)。RAGEmRNA在DM组大鼠阴茎组织的表达明显高于NC组(P<0.01)。结论糖尿病大鼠阴茎组织AGEs水平明显升高,RAGEmRNA高表达,胰岛素和DAP治疗可降低AGEs水平。     

慢阻肺急性加重期患者血浆晚期糖基化终末产物和sRAGE研究

目的研究分析慢性阻塞性肺疾病(慢阻肺)患者血浆中晚期糖基化终末产物(AGEs)和可溶性糖基化终末产物受体(sRAGE)的水平及与慢阻肺患者肺功能的关系。方法选取河北省承德县医院收治的120例慢阻肺患者(慢阻肺组)、50例健康人群(对照组),分别检测两组的血浆AGEs、sRAGE及肺功能等指标。结果慢阻肺组患者的血浆中AGEs(36.25±2.98)ug/m L显著的高于对照组的(28.94±2.31)ug/m L,sRAGE为(338.41±194.26)pg/m L显著的低于对照组的(871.50±226.49)pg/m L且差异均具有统计学意义(P0.05)。慢阻肺组患者血浆AGEs与患者的FEV1%呈显著的负相关关系(r=-0.594,P=0.0000.001);慢阻肺组患者血浆sRAGE与患者的FEV1%呈显著的正相关关系(r=0.552,P=0.0000.001)。结论慢阻肺患者血浆中AGEs、sRAGE水平发生显著的改变,AGEs与患者的肺功能呈负相关性、sRAGE与患者的肺功能呈正相关关系。     

糖化蛋白终末产物诱发糖尿病患者外周血淋巴细胞分泌TNF—α—IL—6的研究

目的研究糖化蛋白终末产物(advancedglycationendproducts,AGEs)是否可刺激人体淋巴细胞分泌TNF-α、IL-6。探讨正常人与糖尿病患者对同一刺激的反应是否一致。方法取正常对照者及糖尿病患者静脉血2ml,分别与PHA和AGEs培养。24h后取上清液测定细胞因子含量。结果糖尿病患者外周血淋巴细胞对PHA和AGEs刺激反应均较正常对照者敏感。AGEs刺激后TNF-α、IL-6分泌在糖尿病组及正常对照组分别为473.2±66.93pg/mlvs254.62±35.14pg/ml(P＜0.02),2400±399pg/mlvs1983.9±294.9pg/ml(P＞0.05)。糖尿病患者对AGEs刺激反应与病程、血糖、体重及性别等因素无关。结论AGEs确实可刺激人体外周血淋巴细胞分泌细胞因子。这一刺激反应在糖尿病患者身上表现尤为敏感;并未发现这一反应与病程、血糖水平、体重等因素有关。提示这一敏感反应可能是糖尿病并发症发生的独立危险因素之一。体外检测这一反应可能成为预测糖尿病并发症发生的一个指标。     

Controlling the receptor for advanced glycation end‐products to conquer diabetic vascular complications

Diabetic vascular complications, such as cardiovascular disease, stroke and microangiopathy, lead to high rates of morbidity and mortality in patients with long‐term diabetes. Extensive intracellular and extracellular formation of advanced glycation end‐products (AGE) is considered a causative factor in vascular injuries in diabetes. Receptor‐dependent mechanisms are involved in AGE‐induced cellular dysfunction and tissue damage. The receptor for AGE (RAGE), originally an AGE‐binding receptor, is now recognized as a member of pattern‐recognition receptors and a pro‐inflammatory molecular device that mediates danger signals to the body. Previous animal studies have shown RAGE dependent of diabetic vascular injuries. Prophylactic and therapeutic strategies focusing on RAGE and its ligand axis will be of great importance in conquering diabetic vascular complications. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00191.x, 2012)     

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     

Correlation between serum advanced glycation end products and dietary intake of advanced glycation end products estimated from home cooking and food frequency questionnaires

Background & aimsTo our knowledge the association between dietary advanced glycation end-products (dAGEs) and cardiometabolic disease is limited. Our aim was to examine the association between dAGEs and serum concentration of carboxymethyl-lysine (CML) or soluble receptor advanced glycation end-products (sRAGEs), and to assess the difference on dAGEs and circulating AGEs according to lifestyle and biochemical measures.Methods and results52 overweight or obese adults diagnosed with type 2 diabetes were included in this cross-sectional analysis. dAGEs were estimated from a Food Frequency Questionnaire (FFQ) or from a FFQ + Home Cooking Frequency Questionnaire (HCFQ). Serum concentrations of CML and sRAGEs were measured by ELISA. Correlation tests were used to analyze the association between dAGEs derived from the FFQ or FFQ + HCFQ and concentrations of CML or sRAGEs. Demographic characteristics, lifestyle factors and biochemical measures were analyzed according to sRAGEs and dAGEs using student t-test and ANCOVA.A significant inverse association was found between serum sRAGEs and dAGEs estimated using the FFQ + HCFQ (r = −0.36, p = 0.010), whereas no association was found for dAGEs derived from the FFQ alone. No association was observed between CML and dAGEs. dAGEs intake estimated from the FFQ + HCFQ was significantly higher among younger and male participants, and in those with higher BMI, higher Hb1Ac levels, longer time with type 2 diabetes, lower adherence to Mediterranean diet, and higher use of culinary techniques that generate more AGEs (all p values p < 0.05).ConclusionsThese results show knowledge on culinary techniques is relevant to derive the association between dAGEs intake and cardiometabolic risk factors.     

Elevated levels of serum advanced glycation end products in patients with non-alcoholic steatohepatitis

BACKGROUND AND AIM: Advanced glycation end products (AGE), senescent macroprotein derivatives formed at an accelerated rate in diabetes, play important roles in the pathogenesis of diabetic vascular complications. Recently, AGE have also been found to be involved in insulin resistance. Although non-alcoholic steatohepatitis (NASH) is generally considered a hepatic manifestation of insulin resistance, there are no reports showing the link of AGE to NASH. The aim of this study was to evaluate the clinical significance of AGE in patients with NASH. METHODS: Glyceraldehyde-derived AGE levels were assayed from serum obtained from 106 patients: 66 with NASH, 10 with simple steatosis, and 30 controls. RESULTS: Serum glyceraldehyde-derived AGE levels (U/mL) were significantly elevated in NASH patients (9.78 +/- 3.73) compared with simple steatosis (7.17 +/- 2.28, P = 0.018) or healthy controls (6.96 +/- 2.36, P = 0.003). Moreover, these were inversely correlated with adiponectin, an adipocytokine with insulin-sensitizing and anti-inflammatory properties. In addition, immunohistochemistry of glyceraldehyde-derived AGE showed intense staining in the livers of NASH patients. CONCLUSION: The present data suggest that the sustained increase of glyceraldehyde-derived AGE could at least in part contribute to the pathogenesis of NASH. The serum glyceraldehyde-derived AGE level may be a useful biomarker for discriminating NASH from simple steatosis.