Chang Kuo-Hsuan, Liu Kou-Chen, Lai Chao-Sung, Yang Shieh-Yueh, Chen Chiung-Mei
Department of Neurology, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
Department of Electronic Engineering, Artificial Intelligence and Green Technology Research Center, Chang Gung University, Taoyuan, Taiwan.
Front Aging Neurosci. 2021 Nov 8;13:759182. doi: 10.3389/fnagi.2021.759182. eCollection 2021.
The potential biomarkers of Parkinson's disease are α-synuclein and neurofilament light chain (NFL). However, inconsistent preanalytical preparation of plasma could lead to variations in levels of these biomarkers. Different types of potassium salts of EDTA and different centrifugation temperatures during plasma preparation may affect the results of α-synuclein and NFL measurements. In this study, we prepared plasma from eight patients with Parkinson's disease (PD) and seven healthy controls (HCs) by using di- and tri-potassium (K- and K-) EDTA tubes and recruited a separated cohort with 42 PD patients and 40 HCs for plasma samples prepared from whole blood by centrifugation at room temperature and 4°C, respectively, in K-EDTA tubes. The plasma levels of α-synuclein and NFL in K- and K-EDTA were similar. However, the levels of α-synuclein in the plasma prepared at 4°C (101.57 ± 43.43 fg/ml) were significantly lower compared with those at room temperature (181.23 ± 196.31 fg/ml, < 0.001). Room temperature preparation demonstrated elevated plasma levels of α-synuclein in PD patients (256.6 ± 50.2 fg/ml) compared with the HCs (102.1 ± 0.66 fg/ml, < 0.001), whereas this increase in PD was not present by preparation at 4°C. Both plasma preparations at room temperature and 4°C demonstrated consistent results of NFL, which are increased in PD patients compared with HCs. Our findings confirmed that K- and K-EDTA tubes were interchangeable for analyzing plasma levels of α-synuclein and NFL. Centrifugation at 4°C during plasma preparation generates considerable reduction and variation of α-synuclein level that might hinder the detection of α-synuclein level changes in PD.
帕金森病的潜在生物标志物是α-突触核蛋白和神经丝轻链（NFL）。然而，血浆分析前准备不一致可能导致这些生物标志物水平的变化。血浆制备过程中不同类型的乙二胺四乙酸（EDTA）钾盐以及不同的离心温度可能会影响α-突触核蛋白和NFL测量结果。在本研究中，我们使用二钾（K-）和三钾（K-）EDTA管从8例帕金森病（PD）患者和7例健康对照（HCs）中制备血浆，并招募了一个单独的队列，其中42例PD患者和40例HCs，分别在K-EDTA管中于室温及4°C下通过全血离心制备血浆样本。K-和K-EDTA中α-突触核蛋白和NFL的血浆水平相似。然而，4°C下制备的血浆中α-突触核蛋白水平（101.57±43.43 fg/ml）与室温下（181.23±196.31 fg/ml，<0.001）相比显著降低。室温制备显示PD患者血浆中α-突触核蛋白水平（256.6±50.2 fg/ml）高于HCs（102.1±0.66 fg/ml，<0.001），而4°C制备时PD患者并未出现这种升高。室温及4°C下的血浆制备均显示NFL结果一致，与HCs相比，PD患者中NFL升高。我们的研究结果证实，K-和K-EDTA管在分析α-突触核蛋白和NFL的血浆水平时可互换。血浆制备过程中在4°C下离心会使α-突触核蛋白水平显著降低并产生变化，这可能会阻碍检测PD中α-突触核蛋白水平的变化。
