视网膜蛋白质组变化反映大脑病理并揭示阿尔茨海默病中的突触和细胞骨架功能障碍

Retinal proteome changes mirror brain pathology and reveal synaptic and cytoskeletal dysfunction in Alzheimer's disease

作者信息Jessica Santiago, Dovilė Pocevičiūtė, Teo Sällberg, Patrik Önnerfjord, Netherlands Brain Bank, Jacob W Vogel, Malin Wennström
PMID42525245
发布时间2026-07-29
DOI10.1007/s00401-026-03054-x

实验完整度

研究包含基于质谱的蛋白质组学分析、免疫荧光验证、跨组织比较、细胞类型映射和通路富集,形成了从分子表型到功能验证的多个独立证据层级。

主要模型

AD患者尸检视网膜组织 AD患者尸检海马组织 非痴呆对照的视网膜和海马组织

重点核对

AD与对照的视网膜和海马组织样本 Lysis和RIPA双重提取方案 质谱分析流程及数据预处理 免疫荧光验证的抗体和浓度 统计模型中的协变量(年龄、性别)

摘要

Visual dysfunction is increasingly recognized as an important feature of Alzheimer's disease, and substantial retinal changes have been documented across multiple studies. Yet the molecular changes underlying retinal neurodegeneration and which retinal protein signatures best track cerebral pathology remain incompletely defined. Here, we performed comprehensive mass spectrometry-based proteomics on paired retinal and hippocampal tissue from the same postmortem donors (8 AD, 8 non-demented controls) to identify disease-associated molecular signatures and assess their overlap between these tissues. Using a sequential dual-extraction protocol, we identified 372 differentially abundant retinal proteins in AD, including established APP-processing regulators (SORL1, BACE1) and synaptic proteins. Retinal proteomes clearly separated AD from controls in principal component analysis, indicating robust AD-related molecular differences in the retina. Notably, 87% of proteins were detected in both retina and hippocampus, with 64 differentially abundant proteins shared between tissues, some of which showed strong cross-tissue correlation. Several retinal proteins also correlated with neuropathological disease stage. Functional enrichment analysis revealed convergent alterations in synaptic organization, cytoskeletal dynamics, mitochondrial function, cell adhesion, and APP metabolism in both tissues. Cell-type mapping using single-cell retinal reference data indicated that most proteomic changes were broadly distributed across cell types, though some proteins showed enrichment in specific populations, such as SORL1 in microglia and EYS in photoreceptors. The molecular changes identified here offer a potential basis for the retinal alterations previously documented through in vivo imaging and histological studies. Their similarities with brain pathology further support the retina as a promising window for assessing cerebral disease.

实验结论

提炼研究问题、关键发现与证据,快速把握文章的核心贡献。

研究问题
阿尔茨海默病视网膜分子变化及其与脑病理的关系尚不清楚,本研究旨在鉴定视网膜中的疾病相关分子特征并评估其与脑病理的相似性。
核心机制
AD视网膜中突触、细胞骨架、线粒体、细胞粘附和APP代谢通路的失调,以及特异蛋白如SORL1、BACE1的变化可能反映脑内病理。
主要证据
通过质谱分析发现372个视网膜差异丰度蛋白,其中64个与海马共享,且部分蛋白(如APMAP、CD109等)在组织间显著相关;免疫荧光验证SORL1在AD视网膜中升高。
研究意义
视网膜蛋白质组变化与脑病理相似,提示视网膜可作为评估脑部疾病的窗口,并可能用于监测阿尔茨海默病的神经退行性变。

研究路径

按研究推进顺序梳理实验设计、验证步骤与关键观察。

1

样本收集与处理

获取AD和对照组视网膜及海马组织,为蛋白质组学分析提供样本。

从荷兰脑库获取8例AD和8例对照的视网膜及海马组织,部分对照缺乏海马;视网膜取自上鼻区域,海马取自CA1区,并进行冷冻保存。

2

蛋白质顺序提取

提取不同溶解性的蛋白质,全面覆盖细胞内外及不同区室的蛋白质。

采用Lysis缓冲液和RIPA缓冲液对组织进行顺序提取,分别收集上清,用于后续质谱分析。

3

质谱分析

鉴定和定量视网膜及海马中的蛋白质。

蛋白质经还原、烷基化、酶解后,进行LC-MS/MS分析,使用数据依赖采集,通过Proteome Discoverer搜索鉴定蛋白质并定量。

4

数据处理与分析

比较AD和对照组蛋白质丰度,识别差异蛋白及共享通路。

使用线性混合效应模型分析差异丰度,PCA、功能富集、相关性等分析,并利用单细胞参考数据映射细胞类型。

5

免疫荧光验证

验证质谱发现的差异蛋白在视网膜中的表达,确认结果的可靠性。

对AD和对照组视网膜切片进行免疫荧光染色,检测SORL1、APMAP、PACSIN3的表达,并量化信号强度。

研究方法

按研究目的归类文中使用的方法,便于定位所需技术。

产品清单

实验环节名称品牌货号
O.C.T.包埋剂Vector Laboratories--
活检打孔器Kai Medical--
Bullet Blender Storm ProNext Advance, Inc.BT24M
裂解缓冲液----
RIPA缓冲液----
胰蛋白酶Promega--
Exploris 480质谱仪Thermo Fisher Scientific--
Vanquish Neo超高效液相色谱系统Thermo Fisher Scientific--
Acclaim PepMap 100 C18预柱Thermo Scientific--
EASY-Spray C18色谱柱--ES902
Proteome Discoverer 2.5Thermo Fisher Scientific--
Omnipore膜Merck--
羊抗兔549Invitrogen--
DAPI----
Vectashield Set封片剂Vector Laboratories--
Zeiss LCM 800Zeiss--
Olympus AX70Olympus--
anti-SORL1抗体AbcamEPR23262-4
anti-APMAP抗体Sigma-AldrichHPA012863
anti-PACSIN3抗体Proteintech10639-1-AP

关键环节

汇总复现实验时建议重点确认的条件及原文阅读提示。

环节核对要点
样本收集
确认AD和对照的诊断标准、组织来源、视网膜区域(上鼻)和海马区域(CA1)
阅读提示:Methods: Tissue samples and donor information
蛋白质提取
Lysis和RIPA缓冲液的具体成分、提取顺序、离心参数
阅读提示:Methods: Processing of retinal and hippocampal samples for mass spectrometry
质谱分析
色谱梯度、质谱采集参数、数据库搜索和定量方法
阅读提示:Methods: Liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis
数据预处理
过滤标准(FDR, 独特肽数, 检测率)、归一化方法、缺失值插补参数
阅读提示:Methods: Preprocessing
差异丰度分析
线性混合效应模型的固定效应和随机效应、协变量(年龄、性别)
阅读提示:Methods: Statistical analyses
免疫荧光验证
抗体克隆号、稀释比例、孵育时间、图像采集和量化参数
阅读提示:Methods: Immunofluorescence staining