Department of Neurology and Alzheimer Research Center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Department of Molecular Neurobiology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands.
Eur J Clin Invest. 2017 Dec;47(12). doi: 10.1111/eci.12853. Epub 2017 Nov 14.
Neutrophil gelatinase-associated lipocalin (NGAL) is an inflammatory protein with gaining increasing interest for its use as marker in blood and cerebrospinal fluid (CSF) for several chronic diseases. Its biochemical properties make it an attractive marker. However, changes in blood and CSF NGAL concentrations during the diurnal rhythm in the elderly are unknown. This information is important for its optimal use as marker in studies with older people.
Serial paired plasma and CSF samples were obtained from 8 healthy elderly males over a 30-hour period. NGAL and cortisol were quantified with ELISA.
No significant changes in plasma and CSF NGAL concentrations over time were found, whereas cortisol (included as internal control) concentrations displayed significant changes over time. Significant circadian patterns were found for plasma NGAL and for cortisol in both plasma and CSF. However, CSF NGAL concentrations did not follow a diurnal pattern in elderly males.
This study illustrates the temporal regulation of NGAL in plasma and CSF, which potentially is a useful reference for studies measuring NGAL as biomarker in older individuals.
中性粒细胞明胶酶相关脂质运载蛋白（NGAL）是一种炎症蛋白，其作为血液和脑脊液（CSF）标志物在多种慢性疾病中的应用引起了越来越多的关注。其生化特性使其成为一种有吸引力的标志物。然而，老年人昼夜节律中血液和 CSF NGAL 浓度的变化尚不清楚。这对于其在老年人研究中作为标志物的最佳应用非常重要。
在 30 小时的时间内，从 8 名健康的老年男性中获得了一系列配对的血浆和 CSF 样本。使用 ELISA 定量测定 NGAL 和皮质醇。
未发现血浆和 CSF NGAL 浓度随时间的显著变化，而皮质醇（作为内部对照）浓度随时间显示出显著变化。在血浆和 CSF 中均发现了血浆 NGAL 和皮质醇的明显昼夜节律模式。然而，CSF NGAL 浓度在老年男性中没有呈现出昼夜模式。
本研究说明了 NGAL 在血浆和 CSF 中的时间调节，这可能为测量老年个体中 NGAL 作为生物标志物的研究提供有用的参考。
