The possible presence of gonadotropin receptors in nonpregnant human uterus and human fetoplacental unit was investigated by light microscope immunocytochemistry using a monoclonal antibody to rat luteal hCG/LH receptors. The receptor antibody cross-reacted with human and bovine hCG/LH receptors and appears to be directed against the receptor rather than other proteins, including HLA class I antigens. Uterus and fetoplacental unit contained receptor antibody-binding sites, which indicates the presence of hCG/LH receptors. In the endometrium these receptors were present in glandular and luminal epithelial cells as well as in stromal cells. In the myometrium the receptors were detected in circular and elongated myometrial smooth muscle and vascular smooth muscle. Comparison of immunostaining intensities, which indicates the presence of different amounts of receptors, revealed that luminal and glandular epithelial cells contained more receptors than stromal cells. These cells, in turn, contained more receptors than myometrial and vascular smooth muscle. All cells in secretory phase uterine specimens contained more receptors than corresponding cells from the proliferative phase of the cycle. Midpregnancy placenta, amniotic epithelium, chorionic cytotrophoblasts, and decidual cells contained hCG/LH receptors. At term pregnancy, while receptors in fetal membranes and decidua continue to be detected, placental tissues did not show any detectable receptors unless the tissues were pretreated with neuraminidase. This indicated that term pregnancy placenta contain hCG/LH receptors masked by sialic acid residues. Comparison of immunostaining intensities suggested that syncytiotrophoblasts contained more receptors than cytotrophoblasts at midpregnancy; mesenchymal cells or blood vessels contained no detectable receptors. There were more receptors in decidua than in fetal membranes at mid- and term pregnancy. While the amniotic epithelial receptors decreased, the receptors in chorionic cytotrophoblasts and decidual cells increased from mid- to term pregnancy. In summary, hCG/LH receptors were demonstrated in the nonpregnant human uterus, human placenta, fetal membranes, and decidua. This indicates that hCG/LH may directly regulate functions of these tissues by endocrine, autocrine, or paracrine mechanisms.

MicroRNAs (miRNAs) have emerged as key regulators of gene expression stability implicated in cell proliferation, apoptosis, and development, whereas their altered expression has been associated with various pathological disorders. The objective of this study was to assess the expression profile of miRNAs and their predicted target genes in placentas from patients with preeclampsia (PC) and preterm (PT) labor as compared to normal term (NT) pregnancies. Using microarray profiling of 820 miRNAs and 18,630 mRNA transcripts, the analysis indicated that 283 of these miRNAs and 9119 mRNAs were expressed in all placentas, of which the relative expression of 20 miRNAs (P < .05 and ≥ 1.5-fold) and 120 mRNAs (P < .05, and 2-fold cutoff) was differentially expressed in PT and PC as compared to NT. The expression of miR-15b, miR-181a, miR-200C, miR-210, miR-296-3p, miR-377, miR-483-5p, and miR-493 and a few of their predicted target genes: matrix metalloproteinases (MMP-1, MMP-9), a disintegrin and metalloproteinase domains (ADAM-17, ADAM-30), tissue inhibitor of metalloproteinase 3 (TIMP-3); suppressor of cytokine signaling 1 (SOCS1); Stanniocalcin (STC2); corticotropin-releasing hormone (CRH), CRH-binding protein (CRHBP); and endothelin-2 (EDN2) were validated in these cohorts using real-time polymerase chain reaction (PCR), some displaying an inverse correlation with the expression of their predicted target genes. Functional analysis indicated that the products of these genes regulate cellular activities considered critical in normal placental functions and those affected by PC and PT labor. In conclusion, the results provide further evidence that placentas affected by PC and PT labor display an altered expression of a number of miRNAs with potential regulatory functions on the expression of specific target genes whose altered expression and function have been associated with these pregnancy complications.

MicroRNAs (miRNAs), through mRNA degradation or repression, act as key regulator of gene expression. Our aim was to identify specific miRNAs that are expressed in endometrium of women with and without endometriosis. We profiled the expression of 287 miRNAs in paired eutopic and ectopic endometrium and isolated endometrial cells using microarray and validated the expression of selected miRNAs using real-time PCR. On the basis of global normalization, 65 of these miRNAs were identified to be expressed above the threshold levels set during the analysis in the endometrium of women without endometriosis with a progressive decline in expression in paired eutopic and ectopic endometrium. Statistical analysis (ANOVA) identified 48 of these miRNAs as differentially expressed among these tissues and 32 miRNAs between isolated endometrial stromal cell (ESC) and glandular epithelial cell (GEC) (P < 0.05). The expression of hsa-miR20a, hsa-miR21, hsa-miR26a, hsa-miR18a, hsa-miR206, hsa-miR181a and hsa-miR142-5p, predicted to target many genes, including TGF-betaR2, ERalpha, ERbeta and PR, respectively, was validated in these tissues and cells using real-time PCR. Treatment of ESC and GEC with 17beta-estradiol and medroxyprogesterone acetate (10(-8) M) differentially regulated the expression of hsa-miR20a, hsa-miR21 and hsa-miR26a, which in part reversed following co-treatment with ICI-182780 and RU-486 (10(-6) M), respectively (P < 0.05). In conclusion, we provided evidence for the expression of a number of differentially expressed miRNAs in eutopic/ectopic endometrium and isolated endometrial cells, opening up the possibility that aberrant/altered expression of some miRNAs whose expression is regulated by the ovarian steroids may influence the expression of specific target genes with central roles in normal endometrial cellular activities and pathogenesis of endometriosis.

Increasing evidence suggests an association between periodontal disease and adverse pregnancy outcomes. Although infection is considered as a risk factor for preterm delivery, the localization of oral bacteria or their antigens in chorioamnionitis placental tissue has never been demonstrated. This study was devised to test the hypothesis that periodontal pathogens may be present and affect human placenta in cases of chorioamnionitis. Using immunocytochemistry, we have identified the presence of Porphyromonas gingivalis antigens in placental tissues. The antigens were detected in the placental syncytiotrophoblasts, chorionic trophoblasts, decidual cells, and amniotic epithelial cells, as well as the vascular cells. There was a substantial increase in immunostaining intensity of the tissues sectioned from women with chorioamnionitis compared to those experiencing normalterm pregnancy, p < 0.019 (Mann-Whitney test). These results suggest that P. gingivalis may commonly colonize placental tissue, and that the presence of the organism may contribute to preterm delivery.