Weeraratna Ashani T, Kalehua Audrey, Deleon Isoke, Bertak Dorothy, Maher Gregory, Wade Michael S, Lustig Ana, Becker Kevin G, Wood William, Walker Douglas G, Beach Thomas G, Taub Dennis D
Laboratory of Immunology, National Institutes of Health, Baltimore, MD 21224, USA.
Exp Cell Res. 2007 Feb 1;313(3):450-61. doi: 10.1016/j.yexcr.2006.10.028. Epub 2006 Nov 1.
Microarray technology was utilized to isolate disease-specific changes in gene expression by sampling across inferior parietal lobes of patients suffering from late onset AD or non-AD-associated dementia and non-demented controls. Primary focus was placed on understanding how inflammation plays a role in AD pathogenesis. Gene ontology analysis revealed that the most differentially expressed genes related to nervous system development and function and neurological disease followed by genes involved in inflammation and immunological signaling. Pathway analysis also implicated a role for chemokines and their receptors, specifically CXCR4 and CCR3, in AD. Immunohistological analysis revealed that these chemokine receptors are upregulated in AD patients. Western analysis demonstrated an increased activation of PKC, a downstream mediator of chemokine receptor signaling, in the majority of AD patients. A very specific cohort of genes related to amyloid beta accumulation and clearance were found to be significantly altered in AD. The most significantly downregulated gene in this data set was the endothelin converting enzyme 2 (ECE2), implicated in amyloid beta clearance. These data were subsequently confirmed by real-time PCR and Western blot analysis. Together, these findings open up new avenues of investigation and possible therapeutic strategies targeting inflammation and amyloid clearance in AD patients.
利用微阵列技术,通过对晚发性阿尔茨海默病(AD)或非AD相关痴呆患者以及非痴呆对照者的下顶叶进行采样,来分离基因表达中疾病特异性的变化。主要重点在于了解炎症在AD发病机制中所起的作用。基因本体分析显示,与神经系统发育和功能以及神经疾病相关的差异表达最显著的基因,其次是参与炎症和免疫信号传导的基因。通路分析还表明趋化因子及其受体,特别是CXCR4和CCR3,在AD中发挥作用。免疫组织学分析显示,这些趋化因子受体在AD患者中上调。蛋白质印迹分析表明,在大多数AD患者中,趋化因子受体信号传导的下游介质蛋白激酶C(PKC)的激活增加。发现与淀粉样β蛋白积累和清除相关的一组非常特定的基因在AD中发生了显著改变。该数据集中下调最显著的基因是内皮素转换酶2(ECE2),它与淀粉样β蛋白清除有关。这些数据随后通过实时PCR和蛋白质印迹分析得到证实。总之,这些发现为针对AD患者炎症和淀粉样蛋白清除的研究和可能的治疗策略开辟了新途径。