Neurodegenerative disorders are one of the greatest global challenges for social and health care in the twenty-first century. Nowadays, determination of cerebrospinal fluid biomarkers for early diagnosis is served by a complex sample preparation procedure with limited diagnostic accuracy. Furthermore, neuroimaging methods are expensive, time-consuming and are not readily available for use as a complimentary and common screening method. Recently, researchers have shown an increased interest in the identification and characterization of new blood biomarkers of dementia to minimize the limitations associated with the current methods of biomarker determination. Amino acids play many important roles in the central nervous system, acting as neuromodulators, neurotransmitters and regulators of energy metabolism. The aim of this study was to evaluate if serum amino acid levels change along the continuum from no cognitive impairment to moderate dementia, and to identify putative biomarkers for early diagnosis of neurodegenerative diseases. Serum levels of 16 amino acids were determined in 3 groups of patients—22 with mild cognitive impairment, 45 with mild dementia and 28 with moderate dementia—by high-performance liquid chromatography (HPLC) with fluorescence detection using AccQ Tag column (Waters). The most exciting result is the significantly elevated concentration of arginine in patients with both stages of dementia as compared to mild cognitive impairment individuals. Recent accumulating evidence suggests the implication of changed arginine metabolism in the pathogenesis of neurodegenerative diseases. We conclude that amino acids profiling might be helpful in searching for biomarkers of neurogenerative diseases. In the present study, we discovered that arginine in plasma may have a putative diagnostic value for dementia.

神经退行性疾病是 21 世纪社会和医疗保健面临的最大全球挑战之一。如今，用于早期诊断的脑脊液生物标志物的测定是通过复杂的样品制备程序来实现的，但诊断准确性有限。此外，神经影像学方法昂贵、耗时，并且不容易用作补充和常见的筛选方法。最近，研究人员对识别和表征痴呆的新血液生物标志物表现出越来越大的兴趣，以最大限度地减少与当前生物标志物测定方法相关的局限性。氨基酸在中枢神经系统中扮演着许多重要的角色，作为神经调节剂、神经递质和能量代谢的调节剂。本研究的目的是评估血清氨基酸水平是否在从无认知障碍到中度痴呆的连续过程中发生变化，并确定用于神经退行性疾病早期诊断的假定生物标志物。使用 AccQ Tag 柱（Waters）通过高效液相色谱（HPLC）和荧光检测，测定了 3 组患者（22 名轻度认知障碍、45 名轻度痴呆和 28 名中度痴呆）的血清 16 种氨基酸水平。最令人兴奋的结果是与轻度认知障碍患者相比，痴呆症两个阶段的患者的精氨酸浓度显着升高。最近越来越多的证据表明精氨酸代谢改变在神经退行性疾病的发病机制中的意义。我们得出结论，氨基酸分析可能有助于寻找神经元疾病的生物标志物。在本研究中，我们发现血浆中的精氨酸可能对痴呆具有诊断价值。