Interleukin‐1α and Interleukin‐1 β in Preterm and Term Human Parturition

Abstract

Interleukin-1 (IL-1) has been implicated in the mechanism of human parturition in the setting of infection. The purpose of this study was to determine the effect of labor (term and preterm) and microbial invasion of the amniotic cavity on amniotic fluid (AF) concentrations IL-1 alpha and IL-1 beta. AF was retrieved by transabdominal amniocentesis from the following groups of women: midtrimester genetic amniocentesis (16 to 18 wk) (N = 15), preterm labor with intact membranes (21 to 36 wk) with or without infection (N = 72), preterm premature rupture of membranes (PROM) (N = 88), and term not in labor or in active labor with or without infection (N = 58). AF was cultured for aerobic and anaerobic bacteria as well as Mycoplasmas. IL-1 was measured with a commercially available immunoassay validated for AF (sensitivity: IL-1 alpha, 157 pg/ml; IL-1 beta, 50 pg/ml). All women at midtrimester had undetectable AF IL-1 alpha and IL-1 beta. Among women in preterm labor with positive AF cultures, IL-1 alpha and IL-1 beta were detectable in the AF in 86.6% (13/15) and 100% (15/15), respectively. In contrast, all women with negative AF cultures without labor (N = 36) had undetectable AF IL-1 alpha concentrations and 52.7% (19/36) had undetectable AF IL-1 beta concentrations. Histopathological chorioamnionitis was present in 92.8% (13/14) of patients who had positive AF cultures and detectable IL-1 in the AF. IL-1 was significantly higher in patients with preterm PROM, labor, and positive AF cultures than in the other subgroups of patients with preterm PROM.(ABSTRACT TRUNCATED AT 250 WORDS)

IL-1β-Mediated Proinflammatory Responses Are Inhibited by Estradiol via Down-Regulation of IL-1 Receptor Type I in Uterine Epithelial Cells

“…IL-1␤ is a major factor in the initiation of infection-related preterm labor and delivery and has been associated with preeclampsia (24 -26). IL-1␤ levels are elevated in the amniotic fluid of pregnancies complicated by intraamniotic infection, and IL-1␤ may be capable of causing preterm labor by up-regulating PG production leading to myometrial contractions (27)(28)(29). Elevated IL-1␤ expression is also observed in the placentas of women with preeclampsia and may be associated with placental hypoxia (26).…”

N,N-Dimethylacetamide Significantly Attenuates LPS- and TNFα-Induced Proinflammatory Responses Via Inhibition of the Nuclear Factor Kappa B Pathway

“…Nuclear translocation of NF-κB triggers the production of proinflammatory cytokines such as tumor necrosis factor (TNF)α and interleukin (IL)-1, which regulate the innate immune response and inflammation (13)(14)(15)(18)(19)(20)(21). Cytokines such as IL-1β, IL-6 and TNFα in turn increase the transcription of genes that mediate tissue remodeling, such as matrix metalloproteinases (MMPs) (22), and also increase synthesis of prostaglandins and other inflammatory mediators (23)(24)(25)(26)(27). In inflammatory cells, activation of NF-κB leads to the induction of inducible nitric oxide synthase (iNOS), which in turn leads to production of the powerful mediator nitric oxide (28).…”

The role of nuclear factor kappa B in human labour

“…Extensive work over the last two decades has implicated cytokines and prostaglandins in the parturition process. Parturition is characterised by an influx of inflammatory cells into the uterus (Young et al 2002) and increased expression of pro-inflammatory cytokines in both preterm and term labour: elevated levels of interleukin-1b (IL-1b), IL-6 and tumour necrosis factor-a (TNF-a) are detected in amniotic fluid (Romero et al 1992, Opsjln et al 1993, Romero et al 1993, Maymon et al 1999, while IL-1b and IL-6 expression is also increased in amnion (Dudley et al 1996, Keelan et al 1999, myometrium and choriodecidua (Keelan et al 1999, Osman et al 2003 and cervicovaginal secretions (Steinborn et al 1996, Tanaka et al 1998. These pro-inflammatory cytokines are thought to contribute to labour onset by stimulating the production of IL-8 and prostaglandins.…”