正常及子痫前期胎盘中超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶的抗氧化活性及mRNA表达

Antioxidant activities and mRNA expression of superoxide dismutase, catalase, and glutathione peroxidase in normal and preeclamptic placentas.

作者信息

Wang Y, Walsh S W

机构信息

Department of Obstetrics and Gynecology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0034, USA.

出版信息

J Soc Gynecol Investig. 1996 Jul-Aug;3(4):179-84.

PMID:8796828

Abstract

OBJECTIVE

Placental production of lipid peroxides is abnormally increased in preeclampsia. The reason for this is not known, but if placental antioxidant enzymes were deficient, lipid peroxides would increase unchecked. In this study, we measured 1) enzyme activities of superoxide dismutase (CuZn-SOD), catalase, and glutathione peroxidase (GSH-Px) and tissue levels of vitamin E, and 2) mRNA expression of CuZn-SOD, catalase, and GSH-Px in normal and preeclamptic placentas.

METHODS

Placental tissues were obtained from normal (n = 16) preeclamptic (n = 12) pregnancies immediately after delivery. Tissue pieces were frozen in liquid nitrogen and stored at -80C until assayed. The enzyme activities of CuZn-SOD, catalase, and GSH-Px and the levels of vitamin E were determined by spectrophotometric assays. Messenger RNA expression of CuZn-SOD, catalase, and GSH-Px was determined by Northern blot analysis.

RESULTS

The activities of CuZn-SOD and GSH-Px and the tissue levels of vitamin E were significantly lower in preeclamptic placentas than in normal placentas (CuZn-SOD: 1.13 +/- 0.49 versus 3.71 +/- 0.71 U/mg protein, P < .01; GSH-Px: 0.18 +/- 0.01 versus 0.26 +/- 0.02 U/mg, P < .01; vitamin E: 0.08 +/- 0.01 versus 0.18 +/- 0.01 microgram/mg, mean +/- standard error, P < .001), whereas the activity of catalase was significantly higher (93 +/- 3 versus 83 +/- 2 U/mg, P < .05). Relative mRNA expression of CuZn-SOD and GSH-Px was significantly lower in preeclamptic than normal placentas (P < 0.05), but there was no significant difference for catalase (P > .4).

CONCLUSIONS

Activities of CuZn-SOD and GSH-Px and the tissue levels of vitamin E are significantly lower in preeclamptic than in normal placentas. 2) Activity of catalase is significantly higher in preeclamptic than in normal placentas. 3) Messenger RNA expression for CuZn-SOD and GSH-Px is lower in preeclamptic placentas. We speculate that decreased antioxidant activity may result in increased lipid peroxide levels in preeclamptic placentas.

摘要

目的

子痫前期患者胎盘脂质过氧化物的产生异常增加。其原因尚不清楚，但如果胎盘抗氧化酶缺乏，脂质过氧化物将不受控制地增加。在本研究中，我们测定了1）超氧化物歧化酶（铜锌超氧化物歧化酶）、过氧化氢酶和谷胱甘肽过氧化物酶（GSH-Px）的酶活性以及维生素E的组织水平，以及2）正常和子痫前期胎盘组织中铜锌超氧化物歧化酶、过氧化氢酶和GSH-Px的mRNA表达。

方法

分娩后立即从正常妊娠（n = 16）和子痫前期妊娠（n = 12）获取胎盘组织。组织块在液氮中冷冻，并储存在-80°C直至检测。通过分光光度法测定铜锌超氧化物歧化酶、过氧化氢酶和GSH-Px的酶活性以及维生素E的水平。通过Northern印迹分析测定铜锌超氧化物歧化酶、过氧化氢酶和GSH-Px的信使RNA表达。

结果

子痫前期胎盘组织中铜锌超氧化物歧化酶和GSH-Px的活性以及维生素E的组织水平显著低于正常胎盘组织（铜锌超氧化物歧化酶：1.13±0.49对3.71±0.71 U/mg蛋白质，P <.01；GSH-Px：0.18±0.01对0.26±0.02 U/mg，P <.01；维生素E：0.08±0.01对0.18±0.01微克/毫克，平均值±标准误差，P <.001），而过氧化氢酶的活性显著更高（93±3对83±2 U/mg，P <.05）。子痫前期胎盘组织中铜锌超氧化物歧化酶和GSH-Px的相对mRNA表达显著低于正常胎盘组织（P < 0.05），但过氧化氢酶无显著差异（P >.4）。

结论

1）子痫前期胎盘组织中铜锌超氧化物歧化酶和GSH-Px的活性以及维生素E的组织水平显著低于正常胎盘组织。2）子痫前期胎盘组织中过氧化氢酶的活性显著高于正常胎盘组织。3）子痫前期胎盘组织中铜锌超氧化物歧化酶和GSH-Px的信使RNA表达较低。我们推测抗氧化活性降低可能导致子痫前期胎盘组织中脂质过氧化物水平升高。