Recent evidence suggests changes in circulating microRNA levels may be promising biomarkers for the clinical diagnosis of Alzheimer disease (AD). We hypothesized that whole-blood microRNAs may be useful to identify individuals with established AD. For this purpose, a sample of community-dwelling women (≥55 years old) carrying the ApoE ∊4 allele were clinically evaluated using the American Psychiatric Association/Diagnostic and Statistical Manual of Mental Disorders, Fourth edition and the Alzheimer Disease Assessment Scale-Cognitive Subscale criteria to diagnose probable AD, and the Clinical Dementia Rating scale to stage the dementia. A set of 25 mature microRNAs was rationally selected for evaluation based on experimental evidence of interaction with genes linked to the late-onset AD neuropathology. Whole-blood concentrations were determined by quantitative real-time polymerase chain reaction. Compared to patients without dementia, a median 3-fold decrease in miR-9 levels was found among patients with AD (P = .001). Our findings support blood-borne miR-9 as a candidate biomarker for probable AD, embodied by evidence from the literature of its implication in amyloidogenesis.

中文翻译：

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晚发性阿尔茨海默病患者的全血 MicroRNA-9 水平降低。


最近的证据表明，循环 microRNA 水平的变化可能是阿尔茨海默病 (AD) 临床诊断的有前途的生物标志物。我们假设全血 microRNA 可能有助于识别患有 AD 的个体。为此，使用美国精神病学协会/精神疾病诊断和统计手册第四版和阿尔茨海默病认知评估量表对携带 ApoE ∊4 等位基因的社区居住女性（≥55 岁）样本进行临床评估诊断可能的 AD 的子量表标准，以及用于对痴呆进行分期的临床痴呆评定量表。根据与迟发性 AD 神经病理学相关基因相互作用的实验证据，合理选择一组 25 种成熟 microRNA 进行评估。通过定量实时聚合酶链反应测定全血浓度。与未患痴呆症的患者相比，AD 患者的 miR-9 水平中位数下降了 3 倍 (P = .001)。我们的研究结果支持血源性 miR-9 作为可能 AD 的候选生物标志物，文献证据表明其在淀粉样蛋白生成中的作用。