一氧化氮及血液净化治疗对糖尿病肾病患者血浆晚期糖基化终产物水平的影响

目的　观察不同血液净化治疗方法及血浆一氧化氮 (NO)对终末期糖尿病肾病 (DN)患者血浆晚期糖基化终产物 (AGEs)的影响。方法　终末期DN患者应用不同血液净化方式治疗 2个月 ,应用荧光分光光度法检测血浆AGEs水平 ;应用α -萘胺显色分光光度计比色法测定血浆中NO浓度。结果　随着肾功能的恶化 ,DN患者的血浆AGEs水平逐渐升高 ,二者呈明显正相关 (r=0 .781)。血液透析 (HD)治疗后AGEs水平变化不明显。单次血液透析滤过 (HDF)使血浆AGEs水平明显降低 (P <0 .0 1) ,治疗两个月后AGEs水平无明显变化。血浆AGEs的水平与NO水平成正相关 (r =0 .5 97)。结论　终末期DN患者血浆AGEs水平受血糖和肾功能双方面的影响 ,其中肾功能对其影响较大。HDF可以有效清除AGEs,但不能有效控制AGEs的透析前水平。未见NO对AGEs在体内有明确的抑制作用。     

Anticonvulsive and neuroprotective effects of synergetic combination of phenytoin and gastrodin on the convulsion induced by penicillin in mice

Phenytoin (PHT) is a commonly prescribed first‐line antiepileptic drug. However, long‐term administration of PHT can cause memory loss and balance disturbance. Gastrodin (GD) is the major bioactive component in Tianma and has sedative, anticonvulsive, memory strengthening, and neuroprotective effects. To combine the two drugs seems attractive; however, little was known about the efficacy of combination therapy. In this study, convulsive attack was successfully induced by penicillin. Isobolographic analysis, memory and balance behavior test, histopathological examination, and Western blot analysis were used to investigate whether the combination therapy of GD and PHT can enhance anticonvulsive effect and reduce the side effects associated with PHT. The GD alone (950.60 mg/kg) and the PHT alone (45.50 mg/kg) could produce an anticonvulsive effect, while comparable effect could be produced by PHT : GD = 1 : 50 (8.59 : 429.27 mg/kg), which reduce the dose of PHT by 81% and GD by 55%. After the chronic anticonvulsive experiments of 16 days, the balance disturbance and short‐/long‐term memory loss were observed in the PHT group, while the PHT + GD therapy can protect the normal balance and memory function. The neuron morphology of hippocampus was preserved, and the number of surviving neurons after combination therapy was more than the model group. The amount of NF‐κB (p65) expression was increased in combination group. All above suggested the potential of the combination of PHT and GD enhances the anticonvulsive effect and the neuroprotective effect and reduces the PHT‐associated memory and balance disturbance. The PHT + GD strategy would provide new possibilities as a novel promising methodology to treat epileptic patients.     

氧化应激和糖基化终末产物在2型糖尿病心肌病变中的作用及其相关性

目的研究氧化应激因素和糖基化终末产物(AGEs)在2型糖尿病(T2DM)心肌病变(DCM)的作用及其相关性。方法选择泰安地区的T2DM患者78例,根据超声心动图、冠状动脉造影等情况,分为单纯T2DM组40例,DCM组38例,另选取正常对照组(NC)40例。测定超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)以及谷胱甘肽过氧化物酶(GHS-PX)等氧化应激指标和糖基化终末产物(AGEs),进行数据统计,并进行相关性分析。结果 T2DM组SOD、NO、GHS-PX较NC组均明显下降,MDA、AGEs则较NC组均明显升高;而DCM组较T2DM组SOD、GHS-PX明显下降,MDA、AGEs明显升高,差异均有统计学意义(P<0.01),而血清NO水平T2DM组较NC组下降,DCM组再次升高,且高于NC组,差异均有统计学意义(P<0.01)。结论氧化应激因素和AGEs在DCM的进展中均有重要作用,促进DCM的发生和发展,且二者之间有相关性,SOD的下降和MDA的升高是AGEs的独立相关因素。     

Human placenta mesenchymal stem cells promote axon survival following optic nerve compression through activation of NF‐κB pathway

Different damage factors are known to trigger cell death in the optic nerves. Use of mesenchymal stem cells is a possible treatments option for traumatic optic nerve injury due to their ability to secrete protective cytokines and recovery factors. In this study, we investigated the neuroprotective effects of human placenta‐derived mesenchymal stem cells (hPMSCs) using an established optic nerve compression model and model of R28 cells that were exposed to hypoxia. Forty percent of axon death was seen in induced in vivo optic nerve injury model (p < .05), and 70% of R28 cells exposed to cobalt chloride (CoCl₂), leading to hypoxia, underwent apoptosis (p < .05). After intravenous injection of hPMSCs into tail vein, there was 25% improvement of axon survival in vivo (p < .05). R28 cells incubated with hPMSCs after exposure to hypoxic condition resulted in 50% increased cell survival compared with R28 cells without hPMSC exposure (p < .05), suggesting the active release of multiple factors related to cell survival. In addition, we found that Nf‐κb protein mediates neuroprotection pathway via up‐regulation of target proteins regulated by hPMSCs. Therefore, we assert that Nf‐κb was one of the mediator proteins in a recovery pathway induced by hPMSCs. In conclusion, these indicate that transactivation of Nf‐κb protein has a critical role in recovery mechanism by hPMSCs. We suggest that hPMSCs have abilities to recover neuronal damages by up‐regulating the expression of genes associated with axon survival and can a better understanding of the possible role of hPMSCs in the treatment modalities of optic nerve injury.     

糖基化终产物对大鼠视网膜超微结构及凋亡的影响

目的观察外源性非酶糖基化终产物(AGEs)对大鼠视网膜超微结构以及细胞凋亡的影响。方法应用鼠血清白蛋白(RSA)体外孵育AGEs修饰蛋白,并将其注入健康大鼠体内,每日一次,连续两周。TUNEL法检测大鼠视网膜凋亡细胞,透射电镜下观察内核层神经细胞的超微变化。结果AGEs组大鼠视网膜内核层可见凋亡阳性细胞,透射电镜下深染细胞明显增多,细胞核缩小、不规则,染色质形成大小不等的团块凝结、边聚于核膜处。胞质深染,细胞器损害。结论AGEs可使大鼠视网膜内核层神经细胞凋亡,超微结构改变。     

Perspectives on medicinal properties of plumbagin and its analogs

Plumbagin is one of the simplest plant secondary metabolite of three major phylogenic families viz. Plumbaginaceae, Droseraceae, and Ebenceae, and exhibits highly potent biological activities, including antioxidant, antiinflammatory, anticancer, antibacterial, and antifungal activities. Recent investigations indicate that these activities arise mainly out of its ability to undergo redox cycling, generating reactive oxygen species and chelating trace metals in biological system. The compound is endowed with a property to inhibit the drug efflux mechanism in drug‐resistant bacteria, thereby allowing intracellular accumulation of the potent drug molecules. An interesting bioactivity exhibited by this compound is the elimination of stringent, conjugative, multidrug‐resistant plasmids from several bacterial strains including opportunistic bacteria, such as Acinetobacter baumannii. Moreover, plumbagin effectively induces apoptosis and causes cell cycle arrest, which is, in part, due to the inactivation of NF‐κB in cancer cells. Therefore, it has been suggested that designing “hybrid drug molecules” of plumbagin by combining it with other appropriate anticancer agents may lead to the generation of novel and potent anticancer drugs with pleiotropic action against human cancers. This comprehensive review is an attempt to understand the chemistry of plumbagin and catalog its biological activities reported to date.     

Silencing of Apis mellifera dorsal genes reveals their role in expression of the antimicrobial peptide defensin‐1

Like all other insects, two key signalling pathways [Toll and immune deficiency (Imd)] regulate the induction of honey bee immune effectors that target microbial pathogens. Amongst these effectors are antimicrobial peptides (AMPs) that are presumed to be produced by the nuclear factors kappa B (NF‐κB) Dorsal and Relish from the Toll and Imd pathways, respectively. Using in silico analysis, we previously proposed that the honey bee AMP defensin‐1 was regulated by the Toll pathway, whereas hymenoptaecin was regulated by Imd and abaecin by both the Toll and Imd pathways. Here we use an RNA interference (RNAi) assay to determine the role of Dorsal in regulating abaecin and defensin‐1. Honey bees have two dorsal genes (dorsal‐1 and dorsal‐2) and two splicing isoforms of dorsal‐1 (dorsal‐1A and dorsal‐1B). Accordingly, we used both single and multiple (double or triple) isoform knockdown strategies to clarify the roles of dorsal proteins and their isoforms. Down‐regulation of defensin‐1 was observed for dorsal‐1A and dorsal‐2 knockdowns, but abaecin expression was not affected by dorsal RNAi. We conclude that defensin‐1 is regulated by Dorsal (Toll pathway).     

Anti‐inflammatory effect of 4‐methylcyclopentadecanone in rats submitted to ischemic stroke

This study aimed to investigate the anti‐inflammatory effect of 4‐methylcyclopentadecanone (4‐MCPC) in rats suffering from a cerebral ischemia/reperfusion (I/R) injury. In this study, the focal cerebral ischemia in rats was induced by middle cerebral artery occlusion (MCAO) for 2 h, and the rats were treated with 4‐MCPC (8 mg/kg) just 0.5 h before reperfusion. The ischemic infarct volume was recorded 24 h after the MCAO. In addition, myeloperoxidase (MPO) activity and TNF‐α and IL‐1β levels in the ischemic cerebral cortex were determined by ELISA, while nuclear translocation of NF‐κB p65 subunit and expression of p‐IκBα were investigated by Western blotting. Our results showed that 4‐MCPC treatment decreased infarct volume significantly, compared with I/R group (16.8%±7.5% vs. 39.7%±10.9%); it reduced MPO activity (0.43 ± 0.10 vs. 1.00 ± 0.51 U/g) and expression levels of TNF‐α (18.90 ± 3.65 vs. 35.87 ± 4.87 ng/g) and IL‐1β (1.68 ± 0.23 vs. 2.67 ± 0.38 ng/g) in ischemic brain tissues of rats. Further study revealed that 4‐MCPC treatment markedly reduced nuclear translocation of NF‐κB p65 subunit and expression of p‐IκBα in ischemic cerebral cortex. Taken together, our results suggest that 4‐MCPC protects against cerebral I/R injury and displays anti‐inflammatory actions through inhibition of the NF‐κB signal pathway.     

Redox Regulation of Inflammation: Old Elements,a New Story

Inflammation is an essential immune response characterized by pain, swelling, redness, heat, and impaired function. A controlled acute inflammatory response is necessary to fight off infection and overcome injury. However, if the inflammatory process persists and enters into the chronic state, it can lead to local and systemic deleterious effects counterproductive to healing and instead constitutes a new pathology. Typically, inflamed tissues are associated with an elevated level of reactive species (reactive oxygen species (ROS)/reactive nitrogen species (RNS)). These ROS/RNS are generated during the respiratory burst of immune cells and are important factors in defense against invading pathogens. Additionally, reactive species are now known to trigger oxidative/nitrosative modifications of biomolecules. While most of these modifications lead to irreparable damage, some are subtle and fully reversible. The reversible modifications can initiate signaling cascades known as “redox signaling.” This redox signaling tightly modulates the inflammatory response. Thus, understanding the complex role of ROS/RNS‐induced redox signaling in inflammation will assist in the design of relevant therapeutic intervention strategies for inflammation‐associated diseases. This review will highlight the impact of oxidative stress and redox signaling on inflammation and inflammation‐associated diseases, with a focus on redox modifications of inflammation‐related proteins.     

The role of endoplasmic reticulum stress in endothelial dysfunction induced by homocysteine thiolactone

Our and other studies have reported that homocysteine thiolactone (HTL) could induce endothelial dysfunction. However, the precise mechanism was largely unknown. In this study, we tested the most possible factor‐endoplasmic reticulum (ER) stress, which was demonstrated to be involved in endothelial dysfunction in cardiovascular disease. Acetylcholine (Ach)‐induced endothelium‐dependent relaxation (EDR) and biochemical parameters were measured in rat isolated aorta. The level of reactive oxygen species (ROS) and NO was designed by specific fluorescent probe DCFH‐DA and DAF‐FM DA separately. The nuclear translocation of the NF‐κB was studied by immune‐fluorescence. The mRNA expression and protein expression of GRP78—a key indicator for the induction of ER stress—were assessed by real‐time PCR and Western blot. Two ER stress inhibitors‐4‐PBA (5 mm ) and Tudca (500 μg/mL)—significantly prevented HTL—impaired EDR and increased NO release, endothelial nitric oxide synthase (eNOS) and SOD activity, decreased ROS production, NADPH activity, NOX‐4 mRNA and MDA level. We also found that 4‐PBA and Tudca blocked HTL‐induced NF‐κB activation thus inhibiting the downstream target gene production including TNF‐α and ICAM‐1. Simultaneously, HTL increased the mRNA and protein level of GRP78. HTL could induce ER stress leading to a downstream enhancement of oxidative stress and inflammation, which finally caused vascular endothelial dysfunction.     

糖化产物在腹膜透析患者体内的变化及意义

目的 探讨蛋白质非酶糖化的早期产物Amadori及糖化终末产物AGEs在非糖尿病尿毒症腹膜透析患者体内的浓度变化及与腹膜透析的相互影响。方法 用氯化硝基四氮唑蓝法测定早期糖化产物-果糖胺,用荧光分光光度计测定糖化终末产物(AGEs)。结果 腹膜透析(CAPD)组的果糖胺与AGEs均比正常组增高,差异有显著性。腹膜平衡试验(PET)组腹膜透析液各测定指标在0h,2h,4h各时间点两两比较均有显著差异(P<0.01)。结论 提示糖化产物在腹膜透析患者体内增多,腹膜透析清除效果差,且可能影响腹膜转运功能。     

糖基化终产物对大鼠视觉诱发电位变化的影响

目的 观察外源性非酶糖基化终产物（AGEs）诱导的大鼠模型视觉诱发电位（VEP）的变化。方法 应用鼠血清白蛋白（RSA）体外孵育AGEs修饰蛋白，并将其注入健康大鼠体内，每日一次，连续两周。对大鼠行VEP检查后取视网膜行HE染色检查。结果 AGEs组大鼠视网膜内核层，神经节细胞层细胞排列疏松，细胞间隙增大，细胞数减少。其VEP表现为潜伏期延长，振幅下降，同正常对照组及RSA组相比，差别有统计学意义。结论 AGEs可作为独立因素导致视网膜组织损害，并引起大鼠VEP改变。     

糖基化终末产物对健康大鼠视网膜单核细胞趋化蛋白-1表达的影响

目的观察外源性非酶糖基化终产物(AGEs)对大鼠视网膜单核细胞趋化蛋白-1(MCP-1)表达的影响。方法应用鼠血清白蛋白(RSA)体外孵育AGEs修饰蛋白,并将其注入健康大鼠体内,每日一次,连续两周。取大鼠视网膜行HE染色及MCP-1免疫组织化学检查。结果AGEs组大鼠视网膜内核层,神经节细胞层细胞排列疏松,细胞间隙增大,细胞数减少。MCP-1在大鼠视网膜内核层,神经节细胞层部分细胞的胞浆中呈阳性表达,AGEs组表达明显增强,其平均灰度值为126.83±2.91,同正常对照组及RSA组相比,差别有统计学意义。结论AGEs可作为独立因素导致视网膜组织损害,并引起正常大鼠视网膜组织中MCP-1表达增高,进而共同参与糖尿病视网膜病变的发展。     

糖基化终产物对大鼠视网膜VEGF表达的定位研究

目的观察外源性非酶糖基化终产物(AGEs)诱导的大鼠模型血管内皮生长因子(VEGF)在视网膜细胞中的定位。方法应用鼠血清白蛋白(RSA)体外孵育AGEs修饰蛋白,并将其注入健康大鼠体内,每日一次,连续两周。对大鼠视网膜行免疫荧光双重标记,激光共聚焦显微镜下观察胶质纤维素酸性蛋白(GFAP)与VEGF的共表达。结果C组及R组大鼠视网膜内界膜下、神经节细胞层见GFAP阳性染色,但整个视网膜未见VEGF阳性染色。A组大鼠除视网膜内界膜下、神经节细胞层有GFAP阳性染色外,其余各层也可见丝条状贯穿于内外界膜之间的GFAP阳性染色,并且在上述部位有GFAP和VEGF的共表达。结论AGEs可使大鼠视网膜Müller细胞分泌VEGF。     

妊娠期高血压患者血清可溶性内皮因子、晚期糖基化终末产物、半乳糖凝集素-1联合检测的临床意义

目的探究妊娠期高血压患者血清可溶性内皮因子(s Eng)、晚期糖基化终末产物(AGEs)、半乳糖凝集素-1(Gal-1)联合检测的临床意义。方法回顾性选取2019年2月至2020年4月我院收治的妊娠期高血压患者98例为研究组,另选取我院进行产检的健康孕妇100例为对照组。两组清晨8:00分别采集空腹静脉血5 ml,使用酶联免疫吸附法检测AGEs、s Eng、Gal-1水平,分析AGEs、s Eng、Gal-1在妊娠期高血压中的表达及意义,分析三者对妊娠期高血压的检测价值。结果与对照组相比,研究组s Eng、AGEs、Gal-1水平上升(P<0.05);且轻度、重度子痫前期患者s Eng、AGEs、Gal-1水平高于高血压组(P<0.05),重度子痫前期组患者高于轻度子痫组(P<0.05);三者联合对妊娠期高血压诊断价值高于AGEs、s Eng、Gal-1单项诊断(P<0.05); AGEs与s Eng水平呈正相关(r=0.685,P=0.003); AGEs与Gal-1呈正相关(r=0.472,P=0.001); s Eng与Gal-1表达呈正相关(r=0.43...