Progesterone modulates the expression of interleukin-6 in cultured term human uterine cervical fibroblasts

Association between interleukin-6 levels in amniotic fluid after rupture of membranes during labour at term pregnancy and successful vaginal delivery: a prospective cohort study

We compared the mean interleukin-6 (IL-6) level in the amniotic fluid after rupture of membranes during labour at term pregnancy according to the delivery methods through prospective cohort study. Cases with premature rupture of membranes, multifetal pregnancy, and major congenital anomalies were excluded. Amniotic fluid was obtained from vaginal canal immediately after spontaneous rupture of membranes. A total of 47 cases were analysed, and 72.3% (34/47) had successful vaginal delivery. The mean concentration of IL-6 in the amniotic fluid was significantly higher in the vaginal delivery group than in the caesarean section group (5,229 pg/mL vs. 1,702 pg/mL, p = .022). The concentration of IL-6 from the amniotic fluid tended to increase as the cervical dilatation increased. The association between high IL-6 level (>2,500 pg/mL) and successful vaginal delivery was not significant after adjusting the degree of cervical dilatation in multivariate logistic regression analysis. IMPACT STATEMENTWhat is already known on this subject? Multiparity, active and strong uterine contractions, dilated cervical os, and the position of foetal head are known clinical factors affecting the successful vaginal delivery. There are few studies on markers for successful vaginal delivery in patients with labour.What do the results of this study add? The mean value of IL-6 concentration from the amniotic fluid collected from vagina immediately after rupture of membranes was significantly higher in the patients who had resulted in successful vaginal delivery than those who had failed.What are the implications are of these findings for clinical practice and/or further research? Measurement of IL-6 concentration in the amniotic fluid from vaginal canal in patients with labour might help to predict the successful vaginal delivery and shorten the time before decision of caesarean section.

Metformin inhibits estradiol and progesterone-induced decidualization of endometrial stromal cells by regulating expression of progesterone receptor, cytokines and matrix metalloproteinases

BACKGROUND

Polycystic ovary syndrome (PCOS) is a serious threat for reproductive-aged women. Metformin has been used for the treatment of PCOS. However, its molecular mechanism in decidualization process of PCOS has not been well featured.

METHODS

RT-qPCR analysis was used to detect expression patterns of progesterone receptor (PGR), estradiol receptor alpha (ERα), Cytokeratin 8 and Vimentin in endometrial tissues of PCOS and non-PCOS patients. RT-qPCR assay was also employed to determine mRNA expression of prolactin, Insulin-like growth factor-binding protein 1 (IGFBP-1), matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP9). Cytokine secretion were measured by matching ELISA kits. Protein expression of p-ERK1/2, ERK1/2, p-p38 MAPK, p38 MAPK, and PGR (PGRA and PGRB) was tested by western blot assay.

RESULTS

PGR expression was upregulated in PCOS patients. Metformin alleviated estradiol (E2) and progesterone (P4) (EP)-induced decidualization of endometrial stromal cells. Abnormal cytokine secretion was observed in EP-stimulated endometrial stromal cells in the absence or presence of metfromin. Metformin suppressed EP-induced MMP-2 and MMP-9 upregulation. Metformin alleviated EP-triggered p38 MAPK inactivation and PGR (PGRA and PGRB) expression. Metfromin had no effect on ERK1/2 signaling in EP-stimulated endometrial stromal cells.

CONCLUSION

Metformin alleviated EP-induced decidualization of endometrial stromal cells by modulating secretion of multiple cytokines, inhibiting expression of MMP-2 and MMP-9, activating p38-MAPK signaling and reducing PGR expression, providing a deep insight into the molecular basis of metfromin therapy for PCOS patients.

Interaction Between Progesterone and Interleukin-1β in Modulating Progesterone Receptor Expression and the Inflammatory Phenotype in Human Cervical Fibroblasts

Progesterone helps maintain cervical structure during pregnancy via the progesterone receptor (PR). Two PR isoforms exist, PR-A and PR-B, which have overlapping as well as isoform-specific target genes. During late gestation, leukocytes infiltrate the cervical stroma accompanied by increased cervical cytokine levels, resembling an inflammatory process. We examined interleukin (IL)-1β regulation of the expression of PR-A, PR-B, and genes governing prostaglandin synthesis in human cervical fibroblasts (HCFs). Since progesterone has been shown to exert anti-inflammatory actions, we also examined the capacity of progesterone (R5020) to ameliorate the actions of IL-1β in HCFs. Interleukin-1β induced both PR-A and PR-B mRNA in HCFs. Interleukin-1β induced a rapid and transient loss of both PR-A and PR-B protein, followed by a latent (24 hours) increase in both PR isoforms. R5020 negated the IL-1β-induced increase in PR-A and PR-B mRNA and protein as well as the rapid IL-1β-induced downregulation of nuclear PR. Interleukin-1β induced prostaglandin G/H synthase-2 (PGHS-2), but not prostaglandin G/H synthase-1 (PGHS-1), as well as prostaglandin E synthase-1 (PGES-1), but not prostaglandin F synthase (PGFS). R5020 did not ameliorate IL-1β induction of PGHS-2 or PGES-1. Blockade of prostaglandin synthesis (indomethacin) prevented both the IL-1β-induced increase in PR mRNA and the acute decrease in PR-A and PR-B protein, implicating a role for prostaglandins in regulating PR expression in HCFs. Although progesterone may function to maintain PR expression in a milieu of increasing cytokines in the late gestation human cervix, it does not exert an anti-inflammatory role with regard to prostaglandin E₂ (PGE2) production.

Diversity of progesterone action on lipopolysaccharide-induced expression changes in cultured human cervical fibroblasts according to inflammation and treatment timing

PROBLEM

The effectiveness of progesterone (P4) treatment for preventing preterm births is unclear. Its effects on the uterine cervix were tested using cultured human uterine cervical fibroblasts (UCFs).

METHOD OF STUDY

UCFs were incubated with lipopolysaccharide (LPS) in the presence or absence of P4 under various conditions. mRNA was subjected to PCR arrays and real-time RT-PCR to assess IL-6, IL-8, IL-1beta, PTGS2, MMP-1, and CXCL10 expression.

RESULTS

When exposed to a high-LPS concentration (2.0 μg/mL), expression of these genes was not suppressed by simultaneous P4 (1.0 μmol/L) treatment, but it was significantly inhibited when P4 was administered 1 hour prior to LPS, with the exception of the chemokines IL-8 and CXCL10. Expression of all genes was restricted by P4 under low-level LPS (0.2 μg/mL) stimulation, especially when administered prior to LPS treatment.

CONCLUSION

These data suggest that early or prophylactic P4 administration is an effective and important measure for reducing preterm birth risk.

17-alpha Hydroxyprogesterone caproate did not reduce the rate of recurrent preterm birth in a prospective cohort study

BACKGROUND

17-alpha Hydroxyprogesterone caproate for prevention of recurrent preterm birth is recommended for use in the United States.

OBJECTIVE

We sought to assess the clinical effectiveness of 17-alpha hydroxyprogesterone caproate to prevent recurrent preterm birth ≤35 weeks compared to similar births in our obstetric population prior to the implementation of 17-alpha hydroxyprogesterone caproate.

STUDY DESIGN

This was a prospective cohort study of 17-alpha hydroxyprogesterone caproate in our obstetric population. The primary outcome was the recurrence of birth ≤35 weeks for the entire study cohort compared to a historical referent rate of 16.8% of recurrent preterm birth in our population. There were 3 secondary outcomes. First, did 17-alpha hydroxyprogesterone caproate modify a woman's history of preterm birth when taking into account her prior number and sequence of preterm and term births? Second, was recurrence of preterm birth related to 17-alpha hydroxyprogesterone caproate plasma concentration? Third, was duration of pregnancy modified by 17-alpha hydroxyprogesterone caproate treatment compared to a prior preterm birth?

RESULTS

From January 2012 through March 2016, 430 consecutive women with prior births ≤35 weeks were treated with 17-alpha hydroxyprogesterone caproate. Nearly two thirds of the women (N = 267) began injections ≤18 weeks and 394 (92%) received a scheduled weekly injection within 10 days of reaching 35 weeks or delivery. The overall rate of recurrent preterm birth was 25% (N = 106) for the entire cohort compared to the 16.8% expected rate (P = 1.0). The 3 secondary outcomes were also negative. First, 17-alpha hydroxyprogesterone caproate did not significantly reduce the rates of recurrence regardless of prior preterm birth number or sequence. Second, plasma concentrations of 17-alpha hydroxyprogesterone caproate were not different (P = .17 at 24 weeks; P = .38 at 32 weeks) between women delivered ≤35 weeks and those delivered later in pregnancy. Third, the mean (±SD) interval in weeks of recurrent preterm birth before 17-alpha hydroxyprogesterone caproate use was 0.4 ± 5.3 weeks and the interval of recurrent preterm birth after 17-alpha hydroxyprogesterone caproate treatment was 0.1 ± 4.7 weeks (P = .63). A side effect of weekly 17-alpha hydroxyprogesterone caproate injections was an increase in gestational diabetes. Specifically, the rate of gestational diabetes was 13.4% in 17-alpha hydroxyprogesterone caproate-treated women compared to 8% in case-matched controls (P = .001).

CONCLUSION

17-alpha Hydroxyprogesterone caproate was ineffective for prevention of recurrent preterm birth and was associated with an increased rate of gestational diabetes.

Vaginal progesterone, but not 17α-hydroxyprogesterone caproate, has antiinflammatory effects at the murine maternal-fetal interface

OBJECTIVE

Progestogen (vaginal progesterone or 17-alpha-hydroxyprogesterone caproate [17OHP-C]) administration to patients at risk for preterm delivery is widely used for the prevention of preterm birth (PTB). The mechanisms by which these agents prevent PTB are poorly understood. Progestogens have immunomodulatory functions; therefore, we investigated the local effects of vaginal progesterone and 17OHP-C on adaptive and innate immune cells implicated in the process of parturition.

STUDY DESIGN

Pregnant C57BL/6 mice received vaginal progesterone (1 mg per 200 μL, n = 10) or Replens (control, 200 μL, n = 10) from 13 to 17 days postcoitum (dpc) or were subcutaneously injected with 17OHP-C (2 mg per 100 μL, n = 10) or castor oil (control, 100 μL, n = 10) on 13, 15, and 17 dpc. Decidual and myometrial leukocytes were isolated prior to term delivery (18.5 dpc) for immunophenotyping by flow cytometry. Cervical tissue samples were collected to determine matrix metalloproteinase (MMP)-9 activity by in situ zymography and visualization of collagen content by Masson's trichrome staining. Plasma concentrations of progesterone, estradiol, and cytokines (interferon [IFN]γ, interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, keratinocyte-activated chemokine/growth-related oncogene, and tumor necrosis factor-α) were quantified by enzyme-linked immunosorbent assays. Pregnant mice pretreated with vaginal progesterone or Replens were injected with 10 μg of an endotoxin on 16.5 dpc (n = 10 each) and monitored via infrared camera until delivery to determine the effect of vaginal progesterone on the rate of PTB.

RESULTS

The following results were found: (1) vaginal progesterone, but not 17OHP-C, increased the proportion of decidual CD4+ regulatory T cells; (2) vaginal progesterone, but not 17OHP-C, decreased the proportion of decidual CD8+CD25+Foxp3+ T cells and macrophages; (3) vaginal progesterone did not result in M1→M2 macrophage polarization but reduced the proportion of myometrial IFNγ+ neutrophils and cervical active MMP-9-positive neutrophils and monocytes; (4) 17OHP-C did not reduce the proportion of myometrial IFNγ+ neutrophils; however, it increased the abundance of cervical active MMP-9-positive neutrophils and monocytes; (5) vaginal progesterone immune effects were associated with reduced systemic concentrations of IL-1β but not with alterations in progesterone or estradiol concentrations; and (6) vaginal progesterone pretreatment protected against endotoxin-induced PTB (effect size 50%, P = 0.011).

CONCLUSION

Vaginal progesterone, but not 17OHP-C, has local antiinflammatory effects at the maternal-fetal interface and the cervix and protects against endotoxin-induced PTB.

Agonist-Dependent Downregulation of Progesterone Receptors in Human Cervical Stromal Fibroblasts

Progesterone (P(4)) maintains uterine quiescence during the majority of pregnancy, whereas diminished progesterone receptor (PR) expression and/or activity (ie, functional P(4) withdrawal) promotes parturition. To investigate the regulation of PR expression in cervical stroma, fibroblasts from premenopausal hysterectomy specimens were prepared. Greater than 99% of the cultures were vimentin positive (mesenchymal cell marker) with only occasional cytokeratin-8 positivity (epithelial cell marker) and no evidence of CD31-positive (endothelial cell marker) cells. Cells were immunolabeled with antibodies directed against PRs (PR-A and PR-B), estrogen receptor α (ER-α), and glucocorticoid receptor-α/β (GR-α/β). All cells were uniformly immunopositive for ER-α and GR-α/β but did not express PRs. Incubation of cells with 10(-8) mol/L 17β-estradiol induced a time-dependent increase in PR-A and PR-B messenger RNAs (mRNAs) by quantitative real-time polymerase chain reactions and proteins by immunoblotting and immunofluorescence. Incubation of cervical fibroblasts with PR ligands (medroxyprogesterone acetate or Org-2058) downregulated PR-A and PR-B levels. Coincubation of cells with PR ligands plus RU-486, a PR antagonist, partially abrogated agonist-induced receptor downregulation. Dexamethasone, a pure glucocorticoid, had no inhibitory effect on PR expression. These results indicate that progestins and estrogens regulate PR expression in cervical fibroblasts. We postulate that hormonal regulation of PR expression in the cervical stroma may contribute to functional P(4) withdrawal in preparation for parturition.

Preterm birth and single nucleotide polymorphisms in cytokine genes

Preterm birth (PTB) is an important issue in neonates because of its complications as well as high morbidity and mortality. The prevalence of PTB is approximately 12-13% in USA and 5-9% in many other developed countries. China represents 7.8% (approximately one million) of 14.9 million babies born prematurely annually worldwide. The rate of PTB is still increasing. Both genetic susceptibility and environmental factors are the major causes of PTB. Inflammation is regarded as an enabling characteristic factor of PTB. The aim of this review is to summarize the current literatures to illustrate the role of single nucleotide polymorphisms (SNPs) of cytokine genes in PTB. These polymorphisms are different among different geographic regions and different races, thus different populations may have different risk factors of PTB. SNPs affect the ability to metabolize poisonous substances and determine inflammation susceptibility, which in turn has an influence on reproduction-related risks and on delivery outcomes after exposure to environmental toxicants and pathogenic organisms.

Inhibitory effect of progesterone on cervical tissue formation in a three-dimensional culture system with human cervical fibroblasts

Progesterone supplementation is recommended to prevent preterm birth in women with a short cervix, but the mechanism is unclear. We hypothesize that progesterone acts by altering the composition of the cervical extracellular matrix (ECM). We tested this hypothesis using human cervical fibroblasts in both two-dimensional (2D) and three-dimensional (3D) cultures. For 2D culture, cells were seeded in 6-well plates and cultured with media supplemented with estradiol (10(-8) M), progesterone (10(-7) or 10(-6) M), and vehicle. For 3D culture, the cells were cultured on a porous silk protein scaffold system. Progesterone and estrogen receptors were documented by immunohistochemistry and Western blot analysis. In both 2D and 3D cultures, decreased collagen synthesis was seen with increased progesterone concentration. Three-dimensional cultures could be maintained significantly longer than 2D cultures, and the morphology of 3D cultures appeared similar to native cervical tissue. Thus, further studies were performed in 3D culture. To determine the effect of progesterone concentration, the 3D scaffolds were cultured with estradiol (10(-8) M) and five conditions: vehicle; 10(-9), 10(-8), or 10(-7) M progesterone; or 10(-7) M progesterone plus 10(-6) M mifepristone. The highest progesterone concentration correlated with the least amount of collagen synthesis. Collagen synthesis progressively increased as progesterone concentration decreased. This effect was partially antagonized by mifepristone, suggesting the mechanism is mediated by the progesterone receptor. This hormonally responsive 3D culture system supports the hypothesis that progesterone has a direct effect on remodeling cervical ECM during pregnancy. The 3D culture system could be useful for studying the mechanism of progesterone effects on the cervix.