Gizaw Solomon T, Ohashi Tetsu, Tanaka Masakazu, Hinou Hiroshi, Nishimura Shin-Ichiro
Field of Drug Discovery Research, Faculty of Advanced Life Science and Graduate School of Life Science, Hokkaido University, N21 W11, Sapporo 001-0021, Japan.
Medicinal Chemistry Pharmaceuticals, Co., Ltd, N21 W12, Sapporo 001-0021, Japan.
Biochim Biophys Acta. 2016 Aug;1860(8):1716-27. doi: 10.1016/j.bbagen.2016.03.009. Epub 2016 Mar 8.
Understanding of the significance of posttranslational glycosylation in Alzheimer's disease (AD) is of growing importance for the investigation of the pathogenesis of AD as well as discovery research of the disease-specific serum biomarkers.
We designed a standard protocol for the glycoblotting combined with MALDI-TOFMS to perform rapid and quantitative profiling of the glycan parts of glycoproteins (N-glycans) and glycosphingolipids (GSLs) using human AD's post-mortem samples such as brain tissues (dissected cerebral cortices such as frontal, parietal, occipital, and temporal domains), serum and cerebrospinal fluid (CSF).
The structural profiles of the major N-glycans released from glycoproteins and the total expression levels of the glycans were found to be mostly similar between the brain tissues of the AD patients and those of the normal control group. In contrast, the expression levels of the serum and CSF protein N-glycans such as bisect-type and multiply branched glycoforms were increased significantly in AD patient group. In addition, the levels of some gangliosides such as GM1, GM2 and GM3 appeared to alter in the AD patient brain and serum samples when compared with the normal control groups.
Alteration of the expression levels of major N- and GSL-glycans in human brain tissues, serum and CSF of AD patients can be monitored quantitatively by means of the glycoblotting-based standard protocols.
The changes in the expression levels of the glycans derived from the human post-mortem samples uncovered by the standardized glycoblotting method provides potential serum biomarkers in central nervous system disorders and can contribute to the insight into the molecular mechanisms in the pathogenesis of neurodegenerative diseases and future drug discovery. Most importantly, the present preliminary trials using human post-mortem samples of AD patients suggest that large-scale serum glycomics cohort by means of various-types of human AD patients as well as the normal control sera can facilitate the discovery research of highly sensitive and reliable serum biomarkers for an early diagnosis of AD. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.
了解翻译后糖基化在阿尔茨海默病（AD）中的意义，对于AD发病机制的研究以及疾病特异性血清生物标志物的发现研究愈发重要。
我们设计了一种糖印迹结合基质辅助激光解吸电离飞行时间质谱（MALDI-TOFMS）的标准方案，以使用人类AD尸检样本（如脑组织（解剖的大脑皮层，如额叶、顶叶、枕叶和颞叶区域）、血清和脑脊液（CSF））对糖蛋白（N-聚糖）和糖鞘脂（GSL）的聚糖部分进行快速定量分析。
发现AD患者脑组织与正常对照组脑组织中，从糖蛋白释放的主要N-聚糖的结构谱以及聚糖的总表达水平大多相似。相比之下，AD患者组血清和脑脊液蛋白N-聚糖（如平分型和多分支糖型）的表达水平显著增加。此外，与正常对照组相比，AD患者脑和血清样本中一些神经节苷脂（如GM1、GM2和GM3）的水平似乎发生了变化。
通过基于糖印迹的标准方案，可以定量监测AD患者人脑组织、血清和脑脊液中主要N-聚糖和GSL-聚糖表达水平的变化。
标准化糖印迹方法揭示的源自人类尸检样本的聚糖表达水平变化，为中枢神经系统疾病提供了潜在的血清生物标志物，并有助于深入了解神经退行性疾病发病机制中的分子机制以及未来的药物发现。最重要的是，目前使用AD患者人类尸检样本的初步试验表明，通过各类AD患者以及正常对照血清进行大规模血清糖组学队列研究，有助于发现用于AD早期诊断的高灵敏度和可靠的血清生物标志物。本文是名为“个性化医学中的聚糖”特刊的一部分 客座编辑：戈尔丹·劳克教授。
