Unal Sezin, Ulubas Isik Dilek, Bas Ahmet Yagmur, Erol Sara, Arifoglu İlter, Alisik Murat, Erel Ozcan, Demirel Nihal
a Department of Neonatology , Etlik Zubeyde Hanım Women's Health Teaching and Research Hospital , Ankara , Turkey.
b Department of Clinical Biochemistry , Ankara Ataturk Education and Research Hospital , Ankara , Turkey.
J Matern Fetal Neonatal Med. 2019 Apr;32(7):1111-1116. doi: 10.1080/14767058.2017.1400007. Epub 2017 Nov 13.
Thiols are organic compounds containing sulfhydryl groups which exert antioxidant effects via dynamic thiol-disulfide homeostasis. The shift towards disulfides indicates the presence of oxidative environment. Thiol-disulfide homeostasis has not been evaluated in neonates. We aimed to evaluate dynamic thiol-disulfide homeostasis in preterm infants.
Preterm infants with birth weight less than 1500 g (25-32 weeks of gestation) were included. Infants with major congenital anomaly, perinatal asphyxia, twin to twin transfusion and infants who were mechanically ventilated and nil by mouth for more than 3 days or fed with formula, had intraventricular hemorrhage ≥ grade 2 or sepsis, received blood/blood product transfusion or inotrope treatment and developed bronchopulmonary dysplasia or retinopathy of prematurity (≥ stage 3), and died were excluded thereafter. Serum thiol-disulfide homeostasis was evaluated for three times: (Baseline, first week, third week). Serum native thiol, total thiol and disulfide were measured (µmol/Lt), disulfide:native thiol, disulfide:total thiol, and native thiol:total thiol ratios were calculated. Wilcoxon's test was used to analyze the significance of change in measurements. Baseline results were analyzed for gender and mode of delivery.
Eighty preterm infants [1255 (1080-1415) grams] were included. Baseline values were native thiol: 209.54 ± 41.83 µmol/L; total thiol: 251.70 ± 45.82 µmol/L; disulfide: 21.08 ± 7.43 µmol/Lt; disulfide:native thiol: 10.49 ± 4.62; disulfide:total thiol: 8.45 ± 2.93; native thiol:total thiol: 83.10 ± 5.87. Thiol levels increased in each measurement, disulfide and disulfide/thiol ratios increased in the first week, decreased in the third week, ratio of native/total thiol decreased in the first week, increased in the third week. No effect of gender or mode of delivery on baseline thiol-disulfide homeostasis was detected.
The shift in the thiol-disulfide equilibrium towards disulfides in the first week can be attributed to subjection of infants to many oxidative insults. Furthermore, the thiol predominance in the third week could be explained by the decrease in oxidative events and increase in feeding as a supply of antioxidants. This study, displaying the levels of the dynamic thiol-disulfide homeostasis in preterm infants without obvious risks for increased oxidative stress, may provide acceptable range for thiol-disulfide homeostasis in recovering preterm infants.
硫醇是含有巯基的有机化合物，通过动态硫醇 - 二硫键稳态发挥抗氧化作用。向二硫键的转变表明存在氧化环境。硫醇 - 二硫键稳态尚未在新生儿中进行评估。我们旨在评估早产儿的动态硫醇 - 二硫键稳态。
纳入出生体重小于1500克（妊娠25 - 32周）的早产儿。排除患有严重先天性异常、围产期窒息、双胎输血综合征的婴儿，以及机械通气且禁食超过3天或接受配方奶喂养、脑室内出血≥2级或患有败血症、接受血液/血液制品输血或使用血管活性药物治疗并发展为支气管肺发育不良或早产儿视网膜病变（≥3期）以及死亡的婴儿。对血清硫醇 - 二硫键稳态进行三次评估（基线、第一周、第三周）。测量血清天然硫醇、总硫醇和二硫键（μmol/Lt），计算二硫键：天然硫醇、二硫键：总硫醇以及天然硫醇：总硫醇的比值。采用威尔科克森检验分析测量值变化的显著性。对基线结果按性别和分娩方式进行分析。
纳入80例早产儿[体重1255（1080 - 1415）克]。基线值为天然硫醇：209.54±41.83μmol/L；总硫醇：251.70±45.82μmol/L；二硫键：21.08±7.43μmol/Lt；二硫键：天然硫醇：10.49±4.62；二硫键：总硫醇：8.45±2.93；天然硫醇：总硫醇：83.10±5.87。每次测量时硫醇水平均升高，二硫键及二硫键/硫醇比值在第一周升高，第三周降低，天然硫醇/总硫醇比值在第一周降低，第三周升高。未检测到性别或分娩方式对基线硫醇 - 二硫键稳态有影响。
第一周硫醇 - 二硫键平衡向二硫键的转变可归因于婴儿遭受多种氧化损伤。此外，第三周硫醇占优势可通过氧化事件减少和作为抗氧化剂来源的喂养增加来解释。本研究展示了无明显氧化应激增加风险的早产儿动态硫醇 - 二硫键稳态水平，可为恢复中的早产儿硫醇 - 二硫键稳态提供可接受范围。
