8-Hydroxy-2-deoxyguanosine, a product of oxidative DNA degradation, is increased in the amniotic fluid of preterm births.

OBJECTIVE: 8-Hydroxy-2-deoxyguanosine (8-OH-2dG) is a measurable biomarker of oxidative DNA damage. This study was designed to determine amniotic fluid 8-OH-2dG levels in healthy full-term pregnant women and preterm pregnant women. To reveal the effect of reactive oxygen species on 8-OH-2dG levels, amniotic fluid total oxidant capacity (TOS), total antioxidant capacity (TAC) and oxidative stress index (OSI) were also measured. PATIENTS AND METHODS: A total of 60 patients, 35 patients with full-term pregnancy and 25 patients with preterm pregnancy, participated in the study. Labor occurring before 37 weeks of gestation was considered as spontaneous preterm birth. Amniotic fluid samples were collected from full-term patients during cesarean section or normal vaginal delivery. 8-OH-2dG concentrations in amniotic fluid samples were measured quantitatively by Enzyme-Linked Immunosorbent Assay (ELISA). Amniotic fluid total antioxidant capacity (TAC) and total oxidant capacity (TOC) was determined in amniotic samples. RESULTS: The amniotic fluid 8-OH-2dG levels of the preterm group were significantly higher than the full-term group (60.8±7.02 ng/mL vs. 33.6±4.11 ng/mL, p<0.01). Similarly, TOC levels of the preterm group were significantly higher than the full-term group (89.7±4.80 µmol/L vs. 54.3±6.60 µmol, p<0.02). TAC was significantly higher in the full-term group compared to the preterm group (1.87±0.10 mmol/L vs. 0.97±0.44 mmol/L, p<0.01). The OSI values of the preterm group were significantly higher than the full-term group. A negative and significant correlation was found between gestational age and amniotic fluid 8-OH-2dG levels in the full-term pregnancy group (r=-0.78, p<0.01). A negative and significant correlation was observed between TAC and amniotic fluid 8-OH-2dG levels in the full-term group (r=-0.60, p<0.02). A positive and significant correlation was also detected between TOC, OSI and amniotic fluid 8-OH-2dG levels in the full-term group. There was a negative but insignificant correlation between fetal weight and amniotic fluid 8-OH-2dG levels. The correlation analysis results of the preterm pregnancy group were similar to the full-term group. CONCLUSIONS: Increased reactive oxygen derivatives in preterm birth increase amniotic fluid levels of DNA degradation product 8-OH2dG and may lead to premature rupture of fetal membranes. This is the first clinical study investigating 8-OH-2dG levels in amniotic fluid of preterm birth.

Hydrosalpingeal fluid leads to subfertility via endometrial TNF-α and IL-7 and NF-κB signaling pathways.

OBJECTIVE: To determine the concentrations of the nuclear factor kappa B (NF-κB), tumor necrosis factor-alpha (TNF-α) and interleukin-7 (IL-7) in midluteal phase endometrial samples of infertile patients diagnosed with uni or bilateral hydrosalpinx (HX). PATIENTS AND METHODS: A total of 24 patients who decided to undergo laparoscopic salpingectomy were included in the study. Salpingectomy indications consisted of patients with a diagnosis of hydrosalpinx (n=12) or ectopic pregnancy (n=12). Twelve healthy patients who underwent Pomeroy-type tubal ligation were considered as the second and healthy control group. The diagnosis of hydrosalpinges was made by transvaginal 2D ultrasonography or HSG. All patients in the hydrosalpinges or ectopic pregnancy group underwent laparoscopic salpingectomy. Just before salpingectomy, endometrial samples were obtained from all patients by Pipelle cannula. Endometrial sampling was performed 7-9 days after the LH surge in the control group. IL-7, NF-κB and TNF-α concentrations were measured by ELISA method in the endometrial samples of all three groups. RESULTS: The endometrial IL-7 concentration before salpingectomy of the patients in the hydrosalpinx group was 44.6±6.65 ng/mg wet-tissue. The IL-7 levels of the HX group were significantly higher than those of the patients in the ectopic pregnancy group (19.3±3.06 ng/mg wet tissue versus 44.6±6.65 ng/mg wet tissue, p<0.04). Similarly, IL-7 levels of the HX group were significantly higher than those of the tubal ligation group (6.08±1.48 ng/mg wet tissue versus 44.6±6.65 ng/mg wet tissue, p<0.03). The endometrial TNF-α concentration of the patients in the hydrosalpinx group was 33.20±5.40 ng/mg wet-tissue. The TNF-α value detected in the hydrosalpinx group was significantly higher than both the TNF-α value in the ectopic pregnancy group (11.8±1.07 ng/mg wet-tissue vs. 33.20±5.40 ng/mg wet-tissue, p<0.01) and the TNF-α value in the tubal ligation group (5.30±1.22 ng/mg wet-tissue vs. 33.20±5.40 ng/mg wet-tissue, p<0.01). The pre-salpingectomy endometrial NF-κB concentration of the patients in the hydrosalpinx group was 6.38±1.40 ng/mg wet-tissue. This value is higher than endometrial NF-κB levels in the ectopic pregnancy group (3.67±0.41 ng/mg wet-tissue vs. 6.38±1.40 ng/mg wet-tissue, p<0.02) and NF-κB levels in the tubal ligation group (1.07±0.38 ng/mg wet-tissue vs. 6.38±1.40 ng/mg wet-tissue, p<0.01). CONCLUSIONS: The presence of hydrosalpinx prevents successful implantation by increasing the levels of endometrial proinflammatory cytokines TNF-α, IL-7 and NF-κB.

Disrupted redox balance in utero-placenteal junction may be the main culprit in the occurrence of abruptio placenta.

OBJECTIVE: To determine the oxidant/antioxidant balance and proinflammatory status in amniotic fluids collected during cesarean section of patients diagnosed with abruptio placenta. PATIENTS AND METHODS: Twenty-five patients diagnosed with ablatio placenta with intact membranes who went to emergency cesarean section were included in the study. A diagnosis of AP was made in those who had at least one of the following criteria or, in suspicious cases, two findings. (i) Antepartum hemorrhage starting after 20 weeks of gestation, (ii) presence of retroplacental hematoma on ultrasonography, (iii) severe fetal distress or death, (iv) localized or diffuse uterine tenderness or pain. The control group consisted of 25 patients who presented for delivery, who were not diagnosed with AP, and whose membranes were intact. NF-κB, total oxidant capacity (TOC), total antioxidant capacity (TAC), and oxidative stress index (TOC/TAC=OSI) levels were measured in amniotic fluids collected during cesarean section from both groups. RESULTS: Amniotic fluid TAS values of the AP group were significantly lower than the healthy controls (1.14±0.33 vs. 9.05.±3.40, p<0.01). Amniotic fluid TOS values were significantly increased in the AP group (36.1±8.10 vs. 11.4±2.77, p<0.02). OSI values were significantly higher in the AP group (31.6±9.03 vs. 1.26±0.02, p<0.01). Amniotic fluid NF-κB expression of the AP group was approximately 5 times higher than the control group (10.4±2.56 ng/mL vs. 1.86±0.30 ng/mL, p<0.01). High blood pressure and smoking history were significantly higher in the AP group. Gestational age and fetal birth weight of the AP group were lower than the control group. CONCLUSIONS: Since the increase in amniotic fluid oxidant capacity and proinflammatory cytokine synthesis cannot be neutralized by the antioxidant system, hypoxic cell damage may lead to premature separation of the placenta.