Amniotic Fluid Levels of Tumor Necrosis Factor-α and Soluble Tumor Necrosis Factor Receptor 1 Before and After the Onset of Labor in Normal Pregnancies

Abstract

Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells and promotes the regulation of trophoblast growth and invasion. Tumor necrosis factor receptor 1 (TNF-R1) is a receptor for TNF-alpha, and soluble TNF-R1 (sTNF-R1) is present in amniotic fluid after receptor shedding. We evaluated whether amniotic fluid TNF-alpha and sTNF-R1 levels during labor differed from those before the onset of labor in normal pregnancies. This study enrolled 34 Japanese women experiencing normal pregnancies with single fetuses who had no infection. Of these subjects, 17 went into labor and had subsequent term deliveries (the labor group), and the other 17 underwent cesarean section without labor (the nonlabor group). The average gestational age at entry was 38-39 weeks of gestation. Maternal ages and gestational ages did not differ significantly between the two groups. Amniotic fluid was collected and the TNF-alpha and sTNF-R1 levels were determined by the ELISA method. Each of these levels was compared between the two groups. There was a significant increase in amniotic fluid TNF-alpha levels in the labor group. However, amniotic fluid sTNF-R1 levels did not differ significantly between the two groups. Amniotic fluid TNF-alpha may promote the onset of labor at term and/or term labor contributing to subsequent delivery may induce the production and secretion of TNF-alpha into the amniotic cavity. There was no pregnancy-associated increase in receptor shedding or cell apoptosis at the onset of labor.

Cellular and subcellular localization of aquaporins 1, 3, 8, and 9 in amniotic membranes during pregnancy in mice

“…In the amniotic membrane, apoptosis is induced by TNF-α (Menon et al 2002). Increases in TNF-α expression in amniotic fluid and apoptotic cells in the amniotic membranes are observed in patients undergoing spontaneous delivery with labor and in patients with chorioamnionitis (Hayashi et al 2008;Kataoka et al 2002;Lei et al 1996;Maymon et al 1999). AQP9 expression increases in the presence of spontaneous labor at term and chorioamnionitis (Mittal et al 2009).…”

The Implication of Aquaporin-9 in the Pathogenesis of Preterm Premature Rupture of Membranes

“…The incubation of isolated human neutrophils with anti-AQP9 antibodies resulted in an impaired neutrophil migration [27]. Amniotic fluid tumor necrosis factor-α (TNF-α) expression and apoptotic cells in the amniotic membrane were significantly increased in patients who underwent spontaneous labor at term, which is well-defined to implicate local and systemic activation of the inflammatory cascade, and in patients with HCA [28,29]. Given the significant role of TNF-α in inducing AQP9 expression, AQP9 might contribute to an apoptotic volume decrease of the amniotic epithelial cells initiated by TNF-α [30].…”

ORIGINAL ARTICLE: Profile of Peripheral Blood Neutrophil Cytokines in Diabetes Type 1 Pregnant Women and its Correlation with Selected Parameters in the Newborns

“…We observed that TNF‐α concentration in the late gestation showed a negative correlation with the newborn birth weight. TNF‐α is known to be present in human placental and uterine cells and promote the regulation of trophoblast growth and invasion 27 . It may be considered a regulator of intrauterine bone development of newborns in the uncomplicated pregnancy 28 .…”