ABSTRACT
OBJECTIVE: This study was to determine the levels of cytokines, lipid peroxides, and total peroxyl radical-trapping antioxidative prameter (TRAP) values of amniotic fluid in pregnant women with preterm premature rupture of membranes (PPROM). METHOD: Amniotic fluid samples were obtained by amniocenteses for chromosomal analyses and other indications(control, n=26). Amniotic fluid samples were also obtained by amnioceteses from pregnant women with preterm premature rupture of membranes (n=22). Amniotic fluid cytokines(IL-6, IL-8) were determined by enzyme-linked immunosorbent assay (ELISA). Lipid peroxide levels of amniotic fluid were measured by thiobarbituric acid (TBA) reaction. The TRAP value of amniotic fluid was assessed by measuring the rate of oxygen consuming during controlled lipid peroxidation by 2,2'-azobis-2-amidinopropane hydrochloride, a water soluble peroxyl radical generator. Ascorbic acid and uric acid were measured by high performance liquid chromatography (HPLC) CoulArray detector of water-soluble antioxidants. Retinol, alpha-tocopherol, and gamma- tocopherol were measured by HPLC-CoulArray detector of fat-soluble vitamins. RESULTS: Cytokine levels of amniotic fluid in pregnant women with PPROM(IL-6: 23.37+/-10.61 ng/ml, IL-8: 10.23+/-3.04 ng/ml) were significantly higher than those in normal pregnant women(IL-6: 0.62+/-0.32 ng/ml, IL-8: 0.55 +/- 0.15 ng/ml), (p<0.05). Lipid peroxide levels of the amniotic fluid in pregnant women with PPROM(10.42+/-1.11 nmol/mg protein) were significantly higher than those in normal pregnant women (7.32+/-0.65 nmol/mg protein), (p<0.05). The amniotic fluid obtained from pregnant women with PPROM showed significantly lower TRAP values (0.46+/-0.04 mM) than those from normal pregnant women(0.62+/- 0.03 mM), (p<0.01). Amniotic fluid ascorbic acid levels in pregnant women with PPROM (52.1+/-15.1 nmol/ml) were significantly lower than in normal pregnant women(231.9+/-33.9 nmol/ml), (p<0.01). There were no significant differences of amniotic fluid uric acid, retinol, alpha-tocopherol, and gamma-tocopherol levels between these groups. CONCLUSIONS: This findings suggest that a low antioxidant activity in amniotic fluid may cause PPROM and demonstrate that antioxidant vitamin, ascorbic acid, may act an important factor in the prevention of PPROM.