Expression of Cyclic AMP associated genes on primary culture human myometrial cells
ABSTRACT: During pregnancy, the myometrium remains quiescent but at term, switches to a state capable of producing a series of coordinated contractions for the delivery of the fetus. Myometrial contractions of labour signify the normal physiological end-point of pregnancy but the biochemical onset of labour may occur at or before term via a series of changes in expression of labour associated genes that are responsible for controlling the activity of the uterus during pregnancy and parturition. There is increasing evidence that components of the cAMP-signalling pathway are up-regulated in the human myometrium during pregnancy to promote the relaxation of the myometrium until term. Our aim was to determine which cAMP-associated genes are important during pregnancy and parturition by exposing myometrial cells to forskolin and performing an a gene array. We then plan to study the trend of the cAMP-associated genes at different stages of gestation and during labour. In this study, we used microarrays to elucidate forskolin responsive genes in human myometrium. These data may provide a broader view of gene networks and cellular functions regulated by forskolin in human myometrial cells. In our future study, this will also help us understand the role of cAMP in human parturition. Primary cultures of human myometrial cells were grown from myometrial biopsies obtained at the time of elective caesarean section at term. Cells were exposed to forskolin (100 µM) for 48 hours, and then total RNA were extracted from each culture. Two comparisons were carried out including: 1. Control 2. Forksolin
Project description:This study identifies a transciptomic myometrial profile associated with dystocia in spontanous nulliparous term labour We used microarrays to compare myometrial biopsies obtained at cesarean section from women in spontaneous term labour Women in spontaneous labour undergoing cesarean section for dystocia (slow progressing labour) compared to women who had progressed in the second stage
Project description:Infiltration of human myometrium and cervix with leukocytes and formation of a pro-inflammatory environment within the uterus has been associated with the initiation of both term and preterm parturition. The mechanism regulating the onset of this pro-inflammatory cascade is not fully elucidated. We demonstrate that prokineticin 1 (PROK1) is up-regulated in human myometrium and placenta during labour. Gene array analysis identified 65 genes up-regulated by PROK1 in human myometrium, mainly cytokines and chemokines including: Interleukin-1beta (IL1B), chemokine C-C motif ligand 3 (CCL3) and Colony Stimulating Factor 3 (CSF3). We additionally demonstrate that PROK1 increases expression of chemokines C-C motif ligand 20 (CCL20), Interleukin-6 (IL-6), Interleukin-8 (IL-8), prostaglandin synthase 2 (PTGS2) and prostaglandin E2 and F2α secretion. We propose that PROK1 is a novel inflammatory mediator that can contribute to onset of human parturition at term and partially mediate premature onset of inflammatory pathways during bacterial infection. Total RNA was extracted from human term non-labour myometrium explants treated with prokineticin for 6 and 24 hours compared to vehicle-treated explants. Six biological replicates were analyzed for each treatment and time point. Two of the 6-hour vehicle samples failed a quality-control analysis and were substituted with a 4-hour vehicle treatment from the same tissue sample in each case.
Project description:Inflammation plays a central role in many human diseases. Human parturition also resembles an inflammatory reaction, where progesterone (P4) and progesterone receptors (PRs) have already been demonstrated to suppress contraction-associated gene expression. In our previous studies, we have found that the progesterone actions, including progesterone-induced gene expression and progesterone’s anti-inflammatory effect, are mediated by PR, GR or both. In this study, we used microarrays to find P4 and IL-1β responsive genes and which IL-1β responsive genes were repressed by P4. These data may provide a broader view of gene networks and cellular functions regulated by P4 and IL-1βin human myometrial cells. In our future study, this will also help us understand the role of PR and GR in human parturition. Primary cultures of human myometrial cells were grown from myometrial biopsies obtained at the time of elective caesarean section. Cells were exposed to different stimuli, IL-1β (5ng/mL) and P4 (10 µM), either alone or in combination for 6 h, and then total RNA were extracted from each culture. Three comparisons were carried out including: 1. V vs. P4; 2. V vs. IL-1β; 3. IL-1β vs. IL-1β+P4.
Project description:Infiltration of human myometrium and cervix with leukocytes and formation of a pro-inflammatory environment within the uterus has been associated with the initiation of both term and preterm parturition. The mechanism regulating the onset of this pro-inflammatory cascade is not fully elucidated. We demonstrate that prokineticin 1 (PROK1) is up-regulated in human myometrium and placenta during labour. Gene array analysis identified 65 genes up-regulated by PROK1 in human myometrium, mainly cytokines and chemokines including: Interleukin-1beta (IL1B), chemokine C-C motif ligand 3 (CCL3) and Colony Stimulating Factor 3 (CSF3). We additionally demonstrate that PROK1 increases expression of chemokines C-C motif ligand 20 (CCL20), Interleukin-6 (IL-6), Interleukin-8 (IL-8), prostaglandin synthase 2 (PTGS2) and prostaglandin E2 and F2α secretion. We propose that PROK1 is a novel inflammatory mediator that can contribute to onset of human parturition at term and partially mediate premature onset of inflammatory pathways during bacterial infection. Overall design: Total RNA was extracted from human term non-labour myometrium explants treated with prokineticin for 6 and 24 hours compared to vehicle-treated explants. Six biological replicates were analyzed for each treatment and time point. Two of the 6-hour vehicle samples failed a quality-control analysis and were substituted with a 4-hour vehicle treatment from the same tissue sample in each case.
Project description:Purpose: To chart the human myometrial transcriptomes before and after the onset of labour. Methods: Tophat splice junction mapping of paired-end reads, HTSeq to generate counts, cufflinks to track transcripts, DESeq, edgeR and baySeq to detect differentially expressed genes and principal component analysis for clustering analyses. Results: We mapped on average 14 million paired-end reads per sample (counting each end individually) to the human genome (build hg19) and covered the expressed transcriptome about 13 times with a TopHat-HTSeq workflow. We performed a comparative analysis with an analogous microarray study (Mittal et al., 2010) and found some overlap between the RNA-seq and the microarray data. Conclusions: Our study is the first RNA-seq study of the human myometrium before and after the onset of labour. We show that while microarray and RNA-seq studies may complement each other, RNA-seq has a much greater resolution. At term with and at term without labour human myometrial mRNA profiles were generated by deep sequencing, using Illumina GAIIx (five biological replicates each).
Project description:Preterm birth is multifactorial in origin with several distinct clinical phenotypes of differing etiologies, including idiopathic preterm birth. Preterm birth involves the interaction of genetic, societal and environmental factors such as nutrition, lifestyle and stress that may modulate the length of gestation via the epigenome. DNA methylation is a well-studied epigenetic modification whereby promoter methylation commonly represses gene expression and vice versa. Myometrial tissue was obtained at cesarean section at term with or without labor, preterm without labor, idiopathic preterm labor, and twin gestations with labor. Differences in the myometrial epigenomes were identified at gene promoters, CpG islands, CpG island shores and shelves, gene bodies across the genome between the groups of women with preterm labor of different phenotypes vs. normal term labor. Functional clustering analysis indicated the significantly enriched pathways of hypomethylated genes (permissive) were related to acute inflammatory and acute-phase responses. By contrast, genes that are hypermethylated (repressive) revealed enrichment for contractile fibers and cell. This study provides the first high-resolution DNA methylome of human myometrium with evidence for differences in the methylome that may relate to idiopathic preterm birth via regulation of gene expression. The findings extend previous observations that idiopathic preterm labor is associated with subclinical intrauterine infection and inflammatory pathways and point to targets for further molecular characterization of preterm delivery. Comparison of the human myometrial epigenomes in pregnancies with preterm labor of different phenotypes vs. normal term labor
Project description:Circulating progesterone (P4) levels decline before the onset of parturition in most animals, but not in humans. This has led to the suggestion that there is functional withdrawal of P4 action at the myometrial level prior to labor onset. Mifepristone is widely used to induce human labour In this study, we aimed to establish and validate a model of human myometrial explants for the study of P4 action. Myometrial biopsies obtained at Caesearean section at term were dissected into explants after a portion was immediately snap-frozen (t=0). Transcriptomic comparison of paired explants and primary myometrial cells as well as the hTert immortalized myometrial cell line demonstrated that explants more closely resemble t=0. Biopsies obtained from non-laboring women at elective Caesarean section at term were divided into 3: (i) dissected and immediately snap-frozen (t=0), (ii) dissected into 3x3x3mm3myometrial explants and (iii) processed for primary cell culture. Explants, primary cells at passage 4 (the typical passage our group uses for experiments) and hTERT cells were cultured for a period of 30 hours without treatment. Total RNA was extracted and microarray analysis performed. 6 replicates were used for this study.
Project description:Context: Increased uterine stretch appears to increase the risk of preterm labour, but the mechanism is unknown. Objectives: To identify a targetable mechanism mediating the effect of stretch on human myometrium. Design: Myometrial explants, prepared from biopsies obtained at elective caesarean delivery, were either studied acutely, or were maintained in prolonged culture (up to 65 h) under tension with either a 0.6 g or 2.4 g mass, and compared using in vitro contractility, whole genome array, and qRT-PCR. Results: Increased stretch for 24 or 65 h increased potassium-induced and oxytocin-induced contractility. Gene array identified 62 differentially expressed transcripts after 65 h exposure to increased stretch. Two probes for gastrin-releasing peptide (GRP), a known stimulatory agonist of smooth muscle, were among the top five up-regulated by stretch (3.4-fold and 2.0-fold). Up-regulation of GRP by stretch was confirmed in a separate series of 10 samples using qRT-PCR (2.8-fold, P = 0.01). GRP stimulated contractions acutely when added to freshly obtained myometrial strips in 3 out of 9 cases, but Western blot demonstrated expression of the GRP receptor in 9 out of 9 cases. Prolonged incubation of stretched explants in the GRP antagonists PD-176252 or RC-3095 (65 and 24 h respectively) significantly reduced potassium chloride and oxytocin-induced contractility. Conclusion: Stretch of human myometrium increases contractility and stimulates the expression of a known smooth muscle stimulatory agonist, GRP. Incubation of myometrium in GRP receptor antagonists ameliorates the effect of stretch. GRP may be a target for novel therapies to reduce the risk of preterm birth in multiple pregnancy. 9 paired samples of human myometrium cultured under low (0.6g) or high (2.4g) tension
Project description:Context: Progesterone is important physiologically and therapeutically to maintain uterine quiescence during pregnancy. It acts in part through controlling myometrial gene expression. Objective: To use expression microarray and qRT-PCR validation to determine the changes in gene expression induced by prolonged exposure to a synthetic progestogen. Design: Myometrial explants, obtained at elective Caesarean section (n=9 patients), were maintained in culture, under 0.6g tension, for 3 days in the presence or absence of medroxyprogesterone acetate (MPA, 100nM). Expression array was performed using Illumina human-8 v3 beadchip arrays. Approximately 30% of differentially expressed transcripts were validated in biological replicates (n=10) using qRT-PCR. Results: Transcripts from 114 genes were significantly differentially expressed. These were significantly enriched in inflammatory response (P=0.00001), growth factor activity (P=0.0004) and cytokine activity genes (P=0.008). 34 transcripts were validated using qRT-PCR using an additional independent sample set obtained from 10 further women. There was very close agreement in the fold changes obtained by array and qRT-PCR analysis (r2=0.9, P<0.0001). We confirmed significant down-regulation of a number of genes which have been well characterized as progesterone sensitive, such as IL1B, IL6, PTGS2 and GJA1. However, the top and 6th most down-regulated genes encoded two cytokines, IL11 and IL24, respectively, not previously implicated in mediating the effects of progesterone in myometrium. Both were validated by qRT-PCR (4.3-fold and 2.2-fold down-regulated, both P<0.001). Conclusions: Progestogens control expression of multiple genes in myometrium, including many with no previously recognised role, including IL11 and IL24. It is plausible that proteins encoded by some of these genes may have important, but as yet uncharacterized effects in controlling human parturition. Overall design: 9 paired samples of human myometrium treated with MPA (10-7M) or vehicle
Project description:Long term exposure to incretin hormones is known to have salutory effects on beta cell function and viability. While short-term cAMP induction is known to have a signature CREB-CRTC target gene response, the long-term effects of cAMP on beta cell gene expression are less well understood. We used rat microarray analysis to compare the genome-wide gene expression response to short-term (2 hours) and long-term (16 hours) stimulations of the cAMP agonist forskolin in INS-1 insulinoma cells. INS-1 cells were exposed to forskolin for 2 or 16 hours in RPMI medium containing 10% serum. Control samples wer incubated for the same time without forskolin. Extracted RNA was used for hybridization on Affymetrix rat 1.0 st gene arrays.