Akisu M, Tuzun S, Arslanoglu S, Yalaz M, Kultursay N
Department of Pediatrics and Biochemistry, Ege University Medical School, Izmir, Turkey.
Acta Med Okayama. 2001 Dec;55(6):357-62. doi: 10.18926/AMO/31997.
In the present investigation, we studied the effect of recombinant human erythropoietin (r-HuEPO) on serum malondialdehyde (MDA) as an index of lipid peroxidation, related to iron-catalyzed free radical reaction and erythrocyte superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities in very-low-birth weight (VLBW) infants. Forty premature infants, at gestational ages were less than 33 weeks and birthweights were less than 1,500 g, were enrolled in the study. The study population was randomly divided into 2 groups. Twenty infants in Group 1 (treatment group) were given r-HuEPO, and 20 infants in Group 2 served as the control. r-HuEPO treatment (750 U/kg a week) was initiated on the 10th day of life and continued for 6 weeks. Preterm infants given erythrocyte transfusions during the study were excluded from the results. Serum ferritin and MDA levels, and erythrocyte superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities were analyzed at the end of the first week of life (at the beginning of the study). Subsequently, serum ferritin, and MDA levels were measured at the end of the 3rd and the 6th week. SOD, CAT, and GPX activities in the hemolysate were analyzed at the end of the 4th week. Six infants in the control group and 1 infant in the r-HuEPO group received transfusions through the end of the study, and these infants were excluded from the results. Significantly decreased serum ferritin concentrations were found in the r-HuEPO group compared to those in the control group both at the end of the 3rd and the 6th week (P < 0.05, and P < 0.01, respectively). In addition, serum MDA levels were also significantly reduced in Group 1 compared to control both at the end of the 3rd and the 6th week (P < 0.01 and P < 0.05, respectively). A good correlation was found between serum MDA and ferritin levels in Group 1. When the 2 groups were compared with respect to activities of SOD, CAT, and GPX at the end of the 4th week, no differences were observed. Our findings in this study show that administration of r-HuEPO significantly decreases lipid peroxidation, but does not affect erythrocyte antioxidant enzyme(s) activities in preterm infants. The mechanism responsible for the r-HuEPO-induced decrease in lipid peroxidation may concern inhibition to iron-catalyzed free radical reactions.
在本研究中,我们以血清丙二醛(MDA)作为脂质过氧化指标,研究重组人促红细胞生成素(r-HuEPO)对极低出生体重(VLBW)婴儿铁催化自由基反应相关的脂质过氧化以及红细胞超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GPX)活性的影响。40例孕周小于33周、出生体重小于1500g的早产儿纳入本研究。研究人群随机分为2组。第1组(治疗组)20例婴儿给予r-HuEPO,第2组20例婴儿作为对照组。r-HuEPO治疗(每周750U/kg)于出生后第10天开始,持续6周。研究期间接受红细胞输血的早产儿被排除在结果分析之外。在出生后第一周结束时(研究开始时)分析血清铁蛋白和MDA水平以及红细胞SOD、CAT和GPX活性。随后,在第3周和第6周结束时测量血清铁蛋白和MDA水平。在第4周结束时分析溶血产物中的SOD、CAT和GPX活性。对照组6例婴儿和r-HuEPO组1例婴儿在研究结束前接受了输血,这些婴儿被排除在结果分析之外。与对照组相比,r-HuEPO组在第3周和第6周结束时血清铁蛋白浓度显著降低(分别为P<0.05和P<0.01)。此外,第1组在第3周和第6周结束时血清MDA水平也显著低于对照组(分别为P<0.01和P<0.05)。第1组血清MDA和铁蛋白水平之间存在良好的相关性。在第4周结束时比较两组SOD、CAT和GPX活性,未观察到差异。我们在本研究中的发现表明,给予r-HuEPO可显著降低脂质过氧化,但不影响早产儿红细胞抗氧化酶活性。r-HuEPO诱导脂质过氧化降低的机制可能与抑制铁催化的自由基反应有关。