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Ureaplasma parvum (U. parvum) is gaining recognition as an important pathogen for chorioamnionitis and preterm premature rupture of membranes. We aimed to investigate the roles of progesterone (P4) and a novel progesterone receptor, progesterone receptor membrane component 1 (PGRMC1), in the response of fetal membranes to U. parvum. Fetal membrane cells (amnion, chorion and decidua) were isolated and confirmed to be free of Mycoplasmataceae. Cells were treated with U. parvum (5x106 CFU), and adherence was quantified by qPCR. Amnion and chorion cells were transfected with scrambled siRNA or validated PGRMC1 siRNA for 72h. Cells were then treated with U. parvum for 4h with or without pretreatment with P4 (10−7 M) or ethanol for 1h. Interleukin-8 (IL-8), matrix metalloproteinase 9 (MMP9) and cyclooxygenase (COX-2) mRNA expression were quantified by qRT-PCR. Culture medium was harvested and analyzed for IL-8 and prostaglandin (PGE2) secretion by ELISA and MMP9 activity by zymography. U. parvum had a mean adherence of 15.0±0.6%, 16.9± 3.7% and 4.7±0.3% in cultured amnion, chorion and decidua cells, respectively. Exposure to U. parvum elicited significant inflammatory responses including induction of IL-8, COX-2, PGE2 and MMP9. A possible role of PGRMC1 was identified in the inhibition of U. parvum-stimulated COX-2 and MMP9 mRNA expression in chorion cells and MMP9 activity in amnion cells. On the other hand, it might enhance the U. parvum-stimulated IL-8 protein secretion in amnion cells. P4, mediated through PGRMC1, significantly inhibited U. Parvum-induced MMP9 mRNA and COX-2 mRNA expression in chorion cells. P4 appeared to attenuate U. parvum induced IL-8 mRNA expression in chorion cells, but this P4 effect might not mediated through PGRMC1. In summary, U. parvum preferentially adheres to and induces inflammatory responses in chorion and amnion cells. P4 and PGRMC1 appear to differentially modulate the inflammatory responses induced by U. parvum among amnion and chorion cells. [ABSTRACT FROM AUTHOR]

Objective: Uterine fibroids (leiomyomas) are common benign tumors of the myometrium but their molecular pathobiology remains elusive. These stiff and often large tumors contain abundant extracellular matrix (ECM), including large amounts of collagen, and can lead to significant morbidities. After observing structural multiformities of uterine fibroids, we aimed to explore this heterogeneity by focusing on collagen and tissue stiffness. Methods: For 19 fibroids, ranging in size from 3 to 11 centimeters, from eight women we documented gross appearance and evaluated collagen content by Masson trichrome staining. Collagen types were determined in additional samples by serial extraction and gel electrophoresis. Biomechanical stiffness was evaluated by rheometry. Results: Fibroid slices displayed different gross morphology and some fibroids had characteristics of two or more patterns: classical whorled (n = 8); nodular (n = 9); interweaving trabecular (n = 9); other (n = 1). All examined fibroids contained at least 37% collagen. Tested samples included type I, III, and V collagen of different proportions. Fibroid stiffness was not correlated with the overall collagen content (correlation coefficient 0.22). Neither stiffness nor collagen content was correlated with fibroid size. Stiffness among fibroids ranged from 3028 to 14180 Pa (CV 36.7%; p<0.001, one-way ANOVA). Stiffness within individual fibroids was also not uniform and variability ranged from CV 1.6 to 42.9%. Conclusions: The observed heterogeneity in structure, collagen content, and stiffness highlights that fibroid regions differ in architectural status. These differences might be associated with variations in local pressure, biomechanical signaling, and altered growth. We conclude the design of all fibroid studies should account for such heterogeneity because samples from different regions have different characteristics. Our understanding of fibroid pathophysiology will greatly increase through the investigation of the complexity of the chemical and biochemical signaling in fibroid development, the correlation of collagen content and mechanical properties in uterine fibroids, and the mechanical forces involved in fibroid development as affected by the various components of the ECM. [ABSTRACT FROM AUTHOR]

Objective: Bacterial colonization of the fetal membranes and its role in pathogenesis of membrane rupture is poorly understood. Prior retrospective work revealed chorion layer thinning in preterm premature rupture of membranes (PPROM) subjects. Our objective was to prospectively examine fetal membrane chorion thinning and to correlate to bacterial presence in PPROM, preterm, and term subjects. Study Design: Paired membrane samples (membrane rupture and membrane distant) were prospectively collected from: PPROM = 14, preterm labor (PTL = 8), preterm no labor (PTNL = 8), term labor (TL = 10), and term no labor (TNL = 8), subjects. Sections were probed with cytokeratin to identify fetal trophoblast layer of the chorion using immunohistochemistry. Fluorescence in situ hybridization was performed using broad range 16 s ribosomal RNA probe. Images were evaluated, chorion and choriodecidua were measured, and bacterial fluorescence scored. Chorion thinning and bacterial presence were compared among and between groups using Student's t-test, linear mixed effect model, and Poisson regression model (SAS Cary, NC). Results: In all groups, the fetal chorion cellular layer was thinner at rupture compared to distant site (147.2 vs. 253.7 µm, p<0.0001). Further, chorion thinning was greatest among PPROM subjects compared to all other groups combined, regardless of site sampled [PPROM(114.9) vs. PTL(246.0) vs. PTNL(200.8) vs. TL(217.9) vs. TNL(246.5)]. Bacteria counts were highest among PPROM subjects compared to all other groups regardless of site sampled or histologic infection [PPROM(31) vs. PTL(9) vs. PTNL(7) vs. TL(7) vs. TNL(6)]. Among all subjects at both sites, bacterial counts were inversely correlated with chorion thinning, even excluding histologic chorioamnionitis (p<0.0001 and p = 0.05). Conclusions: Fetal chorion was uniformly thinner at rupture site compared to distant sites. In PPROM fetal chorion, we demonstrated pronounced global thinning. Although cause or consequence is uncertain, bacterial presence is greatest and inversely correlated with chorion thinning among PPROM subjects. [ABSTRACT FROM AUTHOR]