Department of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Brazil.
Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, Brazil.
Res Dev Disabil. 2014 Jun;35(6):1228-36. doi: 10.1016/j.ridd.2014.03.013. Epub 2014 Mar 28.
We previously demonstrated that systemic oxidative stress is present in Down syndrome (DS) patients. In the present study we investigated the antioxidant status in the peripheral blood of DS children and teenagers comparing such status before and after an antioxidant supplementation. Oxidative stress biomarkers were evaluated in the blood of DS patients (n=21) before and after a daily antioxidant intervention (vitamin E 400mg, C 500 mg) during 6 months. Healthy children (n=18) without DS were recruited as control group. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), gamma-glutamyltransferase (GGT), glucose-6-phosphate dehydrogenase (G6PD) and myeloperoxidase (MPO), as well as the contents of reduced glutathione (GSH), uric acid, vitamin E, thiobarbituric acid reactive substances (TBARS), and protein carbonyls (PC) were measured. Before the antioxidant therapy, DS patients presented decreased GST activity and GSH depletion; elevated SOD, CAT, GR, GGT and MPO activities; increased uric acid levels; while GPx and G6PD activities as well as vitamin E and TBARS levels were unaltered. After the antioxidant supplementation, SOD, CAT, GPx, GR, GGT and MPO activities were downregulated, while TBARS contents were strongly decreased in DS. Also, the antioxidant therapy did not change G6PD and GST activities as well as uric acid and PC levels, while it significantly increased GSH and vitamin E levels in DS patients. Our results clearly demonstrate that the antioxidant intervention with vitamins E and C attenuated the systemic oxidative damage present in DS patients.
我们之前的研究表明，唐氏综合征（Down syndrome，DS）患者存在全身氧化应激。在本研究中，我们通过对比 DS 患儿和青少年在抗氧化补充剂治疗前后外周血中的抗氧化状态，研究了他们的抗氧化状态。我们在每日抗氧化干预（维生素 E 400mg，C 500mg）6 个月后，评估了 DS 患者（n=21）血液中的氧化应激生物标志物。我们招募了无 DS 的健康儿童（n=18）作为对照组。测量了超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）、谷胱甘肽还原酶（GR）、谷胱甘肽 S-转移酶（GST）、γ-谷氨酰转移酶（GGT）、葡萄糖-6-磷酸脱氢酶（G6PD）和髓过氧化物酶（MPO）的活性，以及还原型谷胱甘肽（GSH）、尿酸、维生素 E、硫代巴比妥酸反应物质（TBARS）和蛋白羰基（PC）的含量。在抗氧化治疗之前，DS 患者的 GST 活性降低，GSH 耗竭；SOD、CAT、GR、GGT 和 MPO 活性升高；尿酸水平升高；而 GPx 和 G6PD 活性以及维生素 E 和 TBARS 水平没有改变。在抗氧化补充治疗后，SOD、CAT、GPx、GR、GGT 和 MPO 活性下调，而 DS 中 TBARS 含量显著降低。此外，抗氧化治疗并没有改变 G6PD 和 GST 活性以及尿酸和 PC 水平，而显著增加了 DS 患者的 GSH 和维生素 E 水平。我们的研究结果清楚地表明，维生素 E 和 C 的抗氧化干预减轻了 DS 患者的全身氧化损伤。
