An increase in S-glutathionylated proteins in the Alzheimer's disease inferior parietal lobule, a proteomics approach

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by neurofibrillary tangles, senile plaques, and loss of synapses. Many studies support the notion that oxidative stress plays an important role in AD pathogenesis. Previous studies from our laboratory employed redox proteomics to identify oxidatively modified proteins in the AD inferior parietal lobule (IPL) and hippocampus. The proteins were consistent with biochemical or pathological alterations in AD and have been central to further investigations of the disease. The present study focused on the identification of specific targets of protein S-glutathionylation in AD and control IPL by using a redox proteomics approach. For AD IPL, we identified deoxyhemoglobin, alpha-crystallin B, glyceraldehyde phosphate dehydrogenase (GAPDH), and alpha-enolase as significantly S-glutathionylated relative to these brain proteins in control IPL. GAPDH and alpha-enolase were also shown to have reduced activity in the AD IPL. This study demonstrates that specific proteins are sensitive to S-glutathionylation, which most likely is due to their sensitivity to cysteine oxidation initiated by the increase in oxidative stress in the AD brain.     

Autoimmunity to specific citrullinated proteins gives the first clues to the etiology of rheumatoid arthritis

Summary: Rheumatoid arthritis (RA) is now clearly a true autoimmune disease with accumulating evidence of pathogenic disease-specific autoimmunity to citrullinated proteins. Citrullination, also termed deimination, is a modification of arginine side chains catalyzed by peptidylarginine deiminase (PAD) enzymes. This post-translational modification has the potential to alter the structure, antigenicity, and function of proteins. In RA, antibodies to cyclic citrullinated peptides are now well established for clinical diagnosis, though we argue that the identification of specific citrullinated antigens, as whole proteins, is necessary for exploring pathogenic mechanisms. Four citrullinated antigens, fibrinogen, vimentin, collagen type II, and α-enolase, are now well established, with others awaiting further characterization. All four proteins are expressed in the joint, and there is evidence that antibodies to citrullinated fibrinogen and collagen type II mediate inflammation by the formation of immune complexes, both in humans and animal models. Antibodies to citrullinated proteins are associated with HLA ‘shared epitope’ alleles, and autoimmunity to at least one antigenic sequence, the CEP-1 peptide from citrullinated α-enolase (KIHAcitEIFDScitGNPTVE), shows a specific association with HLA-DRB1*0401, *0404, 620W PTPN22, and smoking. Periodontitis, in which Porphyromonas gingivalis is a major pathogenic bacterium, has been linked to RA in epidemiological studies and also shares similar gene/environment associations. This is also the only bacterium identified that expresses endogenous citrullinated proteins and its own bacterial PAD enzyme, though the precise molecular mechanisms of bacterial citrullination have yet to be explored. Thus, both smoking and Porphyromonas gingivalis are attractive etiological agents for further investigation into the gene/environment/autoimmunity triad of RA.     

Neurokinin-1 enables measles virus trans-synaptic spread in neurons

Measles virus (MV), a morbillivirus that remains a significant human pathogen, can infect the central nervous system, resulting in rare but often fatal diseases, such as subacute sclerosing panencephalitis. Previous work demonstrated that MV was transmitted trans-synaptically and that, while a cellular receptor for the hemagglutinin (H) protein was required for MV entry, it was dispensable for subsequent cell-to-cell spread. Here, we explored what role the other envelope protein, fusion (F), played in trans-synaptic transport. We made the following observations: (1) MV-F expression in infected neurons was similar to that seen in infected fibroblasts; (2) fusion inhibitory peptide (FIP), an inhibitor of MV fusion, prevented both infection and spread in primary neurons; (3) Substance P, a neurotransmitter with the same active site as FIP, also blocked neuronal MV spread; and (4) both genetic deletion and pharmacological inhibition of the Substance P receptor, neurokinin-1 (NK-1), reduced infection of susceptible mice. Together, these data implicate a role for NK-1 in MV CNS infection and spread, perhaps serving as an MV-F receptor or co-receptor on neurons.     

新生儿缺氧缺血性脑病血NSE与ET变化及其与高压氧治疗相关性的研究

目的 探讨肿瘤坏死因子-α(TNF-α)和降钙素基因相关肽(CGRP)在新生儿缺氧缺血性脑病(HIE)中的变化及临床意义。方法 采用放射免疫分析法对38例HIE患儿和18例健康足月新生儿血浆TNF-α与CGRP水平进行了同期动态观察。结果 HIE患儿急性期TNF-α,CGRP水平分别为(1.12±0.42) ng/ml,(88.92±23.16) ng/ml;恢复期分别为(0.61±0.18) ng/ml,(68.39±19.32) ng/ml;对照组分别为(0.54±0.15) ng/ml,(66.2±14.54) ng/ml。急性期血浆TNF-α和CGRP水平较恢复期显著增高(P<0.01),并明显高于同期对照组水平(P<0.01),恢复期与正常对照组无显著差异,急性期不同程度HIE与对照组TNF-α,CGRP水平比较,重度HIE组TNF-α,CGRP分别为(1.28±0.41) ng/ml,(118.12±30.25) ng/ml;中度HIE组分别为(0.95±0.3) ng/ml,(86.49±24.36) ng/ml,轻度HIE组分别为(0.63±0.19) ng/ml,(68.31±18.38) ng/ml,重度组明显高于对照组、轻度组及中度组,中度组高于对照组和轻度组,轻度组与对照组无显著性差异。急性期患儿血浆TNF-α与CGRP呈直线正相关关系(r=0.513,P<0.05)。结论 TNF-α和CGRP参与了新生儿HIE的发病过程。急性期TNF-α的增高可能是促发HIE脑损伤的一个重要因素,而CGRP增高在HIE中对脑损伤可能具有一定的保护作用。     

新生儿缺氧缺血性脑病神经元烯醇化酶变化的研究

目的　探讨新生儿缺氧缺血性脑病时神经元烯醇化酶的变化,为HIE的诊断和治疗提供依据。方法　采用病历对照研究,将实验组分为三组:轻、中、重度HIE分别为2 1、4 9、8例;正常对照组73例。测定其血中神经元烯醇化酶的浓度变化。比较各组间检测指标的差异。结果　实验组NSE水平明显高于对照组,组间有显著性差异,P <0 .0 1:且实验组轻、中、重度间有显著性差异,P均<0 .0 5。结论　NSE水平与HIE的病情严重程度相关,是反映HIE严重程度比较客观的指标。     

新生儿缺氧缺血性脑病血清NSE的变化及其与脑CT值的临床研究

目的探讨窒息后新生儿缺氧缺血性脑病(HIE)早期血清神经元特异性稀醇化酶(NSE)的变化及其与脑CT值的相关性,为临床早期诊断HIE脑损伤提供参考指标,协助判断脑损伤程度,为指导临床对治疗效果的判定和预后提供依据。方法随机选取59例符合新生儿缺氧缺血性脑病诊断标准的足月新生儿作为窒息后缺氧缺血性脑病组。窒息后HIE组根据临床表现分为轻度、中度及重度。随机选择20例生后无窒息,其母无任何疾病的健康足月新生儿作为对照组。HIE组及对照组分别测定生后24h内、第7天血清NSE的含量。颅脑CT值在生后第3～5天测定。所有计量资料均采用均数±标准差表示,组间比较采用q检验(Newman-Keuls法),对有相关趋势的变量进行相关分析,以P0.05为有统计学意义。结果 24h内,对照组NSE浓度(35.15±12.10)μg/L,轻度HIE组(56.71±21.77)μg/L,中度HIE组(109.13±60.70μ)g/L,重度HIE组(141.17±26.83)μg/L,HIE组与对照组比较差异有显著性(P0.01),并且HIE各组之间差异有显著性(P0.01)。生后第7天NSE浓度下降,轻度HIE组恢复至正常,但中度、重度HIE组仍高于对照组,与轻度HIE组及对照组相比以及中度、重度之间,差异有显著性(P0.01)。对照组3-5天脑CT检查其结果值大于20Hu。轻度HIE组脑CT值小于18Hu,中度组小于15Hu,重度组小于12Hu。HIE组与对照组比较,差异有显著性(P0.01)。通过对HIE组生后24h血清NSE水平与3-5天的脑CT值进行相关性分析,发现两因素呈显著负相关(r=-0.752,P0.001)。结论 HIE患儿血清NSE在24h内即升高,HIE组与对照组之间,HIE各组之间,差异有显著性。血清NSE在生后24h可作为窒息后脑损伤的早期指标。HIE患儿24h内血清NSE浓度水平与3-5天时脑CT值呈显著负相关,提示脑损伤程度越重,血清NSE水平越高,脑CT值越低。     

病毒性脑炎患儿治疗前后血清NSE、血浆NPY检测的临床意义

目的:探讨了病毒性脑炎患儿治疗前后血清NSE和血浆NPY水平的变化及意义.方法:应用放射免疫分析对32例病毒性脑炎患儿进行了血清NSE和血浆NPY水平测定,并以30例正常健康儿进行比较.结果:在治疗前病毒性脑炎患儿血清NSE和血浆NPY水平非常显著地高于正常儿水平(P＜0.01),经治疗一个月血清NSE和血浆NPY水平与正常儿比较仍有显著性差异(P＜0.05).结论:病毒性脑炎患儿血清NSE和血浆NPY水平的变化与病毒性脑炎的发病机理有密切的关系.     

Novel murine clonal cell lines either express slow or mixed (fast and slow) muscle markers following differentiation in vitro

We have investigated whether the phenotype of myogenic clones derived from satellite cells of different muscles from the transgenic immortomouse depended on muscle type origin. Clones derived from neonatal, or 6- to 12-week-old fast and slow muscles, were analyzed for myosin and enolase isoforms as phenotypic markers. All clones derived from slow-oxidative muscles differentiated into myotubes with a preferentially slow contractile phenotype, whereas some clones derived from rapid-glycolytic or neonatal muscles expressed both fast and slow myosin isoforms. Thus, muscle origin appears to bias myosin isoform expression in myotubes. The neonatal clone (WTt) was cultivated in various medium and substrate conditions, allowing us to determine optimized conditions for their differentiation. Matrigel allowed expressions of adult myosin isoforms, and an isozymic switch from embryonic alpha- toward muscle-specific beta-enolase, never previously observed in vitro. These cells will be a useful model for in vitro studies of muscle fiber maturation and plasticity.     

脑白质损伤早产儿血清IL-6及NSE的变化及其临床意义

目的了解血清白细胞介素-6（IL-6）及神经元特异性烯醇化酶（NSE）的变化对脑白质损伤早产儿早期诊断的价值。方法观察组为脑白质损伤早产儿35例,对照组为正常早产儿35名。采用ELISA分别于生后1、7、14 d检测两组血清IL-6、NSE水平。结果对照组患儿生后第1、7及14天血清IL-6水平分别为（19.14±1.18）pg/ml、（19.14±1.14）pg/ml及（19.11±1.34）pg/ml,观察组患儿分别为（25.19±3.03）pg/ml、（24.48±2.97）pg/ml及（23.74±2.95）pg/ml,观察组显著高于对照组,差异有统计学意义（P均=0.000）。对照组患儿生后第1、7及14天血清NSE水平分别为（4.70±0.36）ng/ml、（4.31±0.29）ng/ml及（4.14±0.30）ng/ml,观察组患儿分别为（6.30±0.89）ng/ml、（6.05±0.86）ng/ml及（5.64±0.75）ng/ml,观察组显著高于对照组,差异有统计学意义（P均=0.000）。结论脑白质损伤早产儿血清IL-6和NSE的浓度明显高于对照组。监测早产儿血清IL-6和NSE水平,对脑白质损伤的诊断和治疗效果的评价具有一定临床价值。     

神经元特异性烯醇化酶光激化学发光免疫分析法的建立

研制检测人血清神经元特异性烯醇化酶(NSE)的光激化学发光免疫分析(AlphaLISA)快速检测试剂盒。采用受体微球用一株NSE单克隆抗体包被,用生物素标记一株单克隆抗体,与链霉亲和素的供体微球共同组成检测试剂盒,优化反应体系并对试剂盒的各项性能指标进行评价。结果显示:自制NSE试剂盒灵敏度为0.149 ng/ml,线性范围为0.149~600ng/ml,分析内、分析间的精密度分别为3.7%~4.3%、3.9%~5.2%,与细胞角蛋白19片段(CYFRA21-1)、非神经元性烯醇化酶(NNE)均无交叉反应,154份临床血清样本用本试剂盒与罗氏化学发光试剂盒检测,其相关系数为0.979。发现自制NSE-AlphaLISA试剂盒的各项性能指标均能达到临床检测要求,可用于临床血清样本NSE浓度的测定。