OBJECTIVE: We aimed to explore the relation between systemic oxidative stress biomarkers excreted in urine and urinary osmolality (Uosm).
METHODS: The current trial was a descriptive, cross-sectional study. We collected seventy-eight samples of 24-h urine in preschoolers who were attending daycare centers in the Western Highlands province of Quetzaltenango, Guatemala. After we measured the total urine volume (Uvol), the aliquot was stored for the later determination of Uosm as a hydration biomarker and to measure 15-isoprostane F2t (F2-Iso) and 8-hydroxydeoxyguanosine (8-OHdG) as biomarkers of cellular oxidation with the use of ELISA assay kits in Spain. Descriptive statistics and linear [Spearman rank-order (rs)] and nonlinear (goodness-of-fit) correlations were performed.
RESULTS: Twenty-four hour Uvols ranged from 65 to 1670 mL, whereas the Uosm varied between 115 and 1102 mOsm/kg. With respect to oxidative biomarkers, the 24-h urinary output of F2-Iso and 8-OHdG had median values of 748 and 2793 ng/d, respectively. The Uvol correlated inversely and significantly with the concentrations of both oxidative biomarkers (F2-Iso rs = -0.603, P < 0.001; 8-OHdG rs = -0.433, P < 0.001), whereas the Uosm was correlated in a direct manner (F2-Iso rs = 0.541, P < 0.001; 8-OHdG rs = 0.782, P < 0.001) when analyzed as a concentration. Associations were weaker when they were analyzed as the total 24-h production.
CONCLUSIONS: Preschool children from the Western Highlands of Guatemala show strong correlations between hydration status measured through the use of Uosm and biomarkers of oxidative stress in urine. Thus, a relatively superior hydration status is associated with a quantitative reduction in urinary excretion of systemic oxidation products. This trial was registered at clinicaltrials.gov as NCT02203890.
目的:我们旨在探讨尿液中排泄的系统性氧化应激生物标志物与尿渗透压(Uosm)之间的关系。
方法:当前的试验是描述性的,横断面研究。我们收集了78个24小时尿液样本,这些样本来自西部高地Quetzaltenango省的日托中心,危地马拉。在我们测量了总尿量(Uvol)后,在西班牙,等分试样储存后用于测定作为水合生物标志物的Uosm,并使用ELISA测定试剂盒测定作为细胞氧化生物标志物的15-异前列腺素F2t(F2-Iso)和8-羟基脱氧鸟苷(8-OHdG).进行了描述性统计和线性[Spearman秩(rs)]和非线性(拟合优度)相关性。
结果:24小时Uvol的范围从65到1670毫升,而Uosm在115和1102mOsm/kg之间变化。关于氧化生物标志物,F2-Iso和8-OHdG的24小时尿量中位数为748和2793ng/d,分别。Uvol与两种氧化生物标志物的浓度成反比且显着相关(F2-Isors=-0.603,P<0.001;8-OHdGrs=-0.433,P<0.001),而以浓度分析时,Uosm以直接方式相关(F2-Isors=0.541,P<0.001;8-OHdGrs=0.782,P<0.001)。当将其分析为24小时的总产量时,关联较弱。
结论:来自危地马拉西部高地的学龄前儿童显示,通过使用Uosm测量的水合状态与尿液中氧化应激的生物标志物之间存在很强的相关性。因此,相对优越的水合状态与全身氧化产物的尿排泄定量减少有关。该试验在clinicaltrials.gov注册为NCT02203890。