Basigin expression and hormonal regulation in mouse uterus during the peri-implantation period

Basigin, a transmembrane glycoprotein belonging to the immunoglobulin superfamily, has been shown to be essential for fertilization and implantation. The aim of this study was to determine the expression and hormonal regulation of basigin gene in mouse uterus during the peri-implantation period. Basigin immunostaining and mRNA were strongly localized in luminal and glandular epithelium on day 1 of pregnancy and gradually decreased to a basal level from day 2-4 of pregnancy. Basigin mRNA expression in the sub-luminal stroma was first detected on day 3 of pregnancy and increased on day 4 of pregnancy. On day 5 of pregnancy, the expression of basigin protein and mRNA was only detected in the implanting embryos, and the luminal epithelium and sub-luminal stroma surrounding the embryos. A similar expression pattern of basigin was also induced in the delayed-implantation uterus which was activated by estrogen injection. On day 6-8 of pregnancy, although a basal level of basigin protein was detected in the secondary decidual zone, basigin mRNA expression was strongly seen in this location. Basigin mRNA was also highly expressed in the decidualized cells under artificial decidualization. Estrogen significantly stimulated basigin expression in the ovariectomized mouse uterus. A high level of basigin immunostaining and mRNA was also seen in proestrus and estrus uteri. These results suggest that basigin expression is closely related to mouse implantation and up-regulated by estrogen.     

Expression of stathmin family genes in the murine uterus during early pregnancy

Stathmin, a cytosolic phosphoprotein that regulates microtubule dynamics during cell-cycle progression, is abundantly expressed at embryo implantation sites in rats. Here, we characterized the expression of stathmin and its family genes in the murine uterus during the peri-implantation period. Stathmin protein was expressed in the glandular and luminal epithelium, blood vessels, and stromal cells on day 3 of pregnancy. On the day of implantation (day 5), stathmin was mainly localized in blood vessels in the endometrium. On day 7, intense stathmin expression was limited to capillary vessels and secondary decidual cells. Stathmin expression was higher at implantation sites than at uterine segments between implantation sites and increased during oil-induced decidualization. Although the artificially-induced deciduoma weights and number of implantation sites were similar between stathmin-knockout (KO) and wild-type (WT) mice, the stathmin-KO mice had fewer newborn pups (reduced by 30%). The expression of alkaline phosphatase, desmin, and cyclin D3 was attenuated in decidual zones of stathmin-KO mice. Messenger RNA level of the stathmin family gene, SCG10, was high at the time of decidualization in WT and stathmin-KO mice. In contrast, the others of stathmin family members, SCLIP and RB3 were highly expressed in stathmin-KO mice compared to WT mice. These results suggest that stathmin and stathmin family genes are expressed in the murine endometrium with enhanced expression in the implantation or the decidualization process.     

Peroxisome proliferator-activated receptor delta expression and regulation in mouse uterus during embryo implantation and decidualization

The aim of this study was to examine the expression and regulation of peroxisome proliferator-activated receptor (PPAR) PPARdelta gene in mouse uterus during early pregnancy by in situ hybridization and immunohistochemistry. PPARdelta expression under pseudopregnancy, delayed implantation, hormonal treatment, and artificial decidualization was also investigated. There was a very low level of PPARdelta expression on days 1-4 of pregnancy. On day 5 when embryo implanted, PPARdelta expression was exclusively observed in the subluminal stroma surrounding the implanting blastocyst. No corresponding signals were seen in the uterus on day 5 of pregnancy. There was no detectable PPARdelta signal under delayed implantation. Once delayed implantation was terminated by estrogen treatment and embryo implanted, a strong level of PPARdelta expression was induced in the subluminal stroma surrounding the implanting blastocyst. Estrogen treatment induced a moderate level of PPARdelta expression in the glandular epithelium, while progesterone treatment had no effects in the ovariectomized mice. A strong level of PPARdelta expression was seen in the decidua on days 6-8 of pregnancy. PPARdelta expression was also induced under artificial decidualization. These data suggest that PPARdelta expression at implantation sites require the presence of an active blastocyst and may play an essential role for blastocyst implantation.     

Subtilisin proprotein convertase-6 expression in the mouse uterus during implantation and artificially induced decidualization

During implantation, a balance of factors regulates the invasive properties of the embryo and the anti-invasive properties of uterine decidua. Although antiproteinases such as the metalloproteinase inhibitor TIMP-3 are thought to play critical roles in preventing the overaggressive invasion of trophoblasts, the mechanism of antiproteinase regulation is unknown. Recently, the prohormone convertase SPC-6 has been found to be co-expressed in embryo-proximal decidua in association with TIMP-3. As members of this serine proteinase family are known to activate latent TGFbeta family members which regulate decidual TIMP-3 levels, we sought to characterize the expression of SPC-6 during pregnancy and artificial decidualization. In this study, we demonstrate that the zone of SPC-6 gene expression exhibits a great degree of temporal and spatial overlap with TIMP-3 gene expression in uterine decidua from E5.5 through to E8.5. Like TIMP-3, we demonstrate that SPC-6 expression is induced during the decidual cell response using an in vivo model of artificial decidualization. Both the secreted and membrane bound forms of SPC-6 are expressed throughout the period of decidualization, suggesting that SPC-6 may play multiple roles during this developmental period. This is confirmed by our observation of the movement of SPC-6 expression to the presumptive placental region, as TIMP-3 expression regresses at the implantation site.     

Expression and regulation of histidine decarboxylase mRNA expression in the uterus during pregnancy in the mouse

It has been hypothesized that hormonally regulated histamine production plays a role in preparation of the uterus for implantation. Histidine decarboxylase (HDC) is the rate-limiting enzyme for histamine production. The current study was designed to determine intrauterine expression of HDC mRNA expression during pregnancy in the mouse. High levels of HDC mRNA expression were observed in the preimplantation mouse uterus with peak expression occurring on day 4. High levels of HDC mRNA expression were also detected in the post-implantation uterus. In an effort to determine whether HDC mRNA is regulated by pro-inflammatory cytokines, the HDC mRNA pattern was compared to intrauterine expression of mRNA's for interleukin-1alpha (IL-1alpha), IL-1beta, macrophage chemotactic protein-1 (MCP-1) and RANTES (regulated on activation, normal T expressed and secreted) during the peri-implantation period. IL-1beta, MCP-1 and RANTES mRNA levels were increased in the uterus on days 1-2 and on days 4-5. Increased expression of IL-1alpha mRNA was observed on days 1-2 and days 5-7. There was no clear relationship between HDC mRNA expression and cytokine/chemokine mRNA expression. Progesterone-stimulated intrauterine expression of HDC mRNA. Intrauterine cytokine/chemokine mRNA was also hormonally regulated. This data allowed the possibility that one or more of these pro-inflammatory cytokines could be involved in regulating intrauterine HDC mRNA production. Recombinant IL-1alpha, IL-1beta, MCP-1 and RANTES all failed to induce HDC mRNA expression in the preimplantation uterus in a mouse pseudopregnancy model. At the same time, IL-1beta induced the expression of mRNA for each of the four cytokines/chemokines. Despite the fact that these were also produced in the uterus during pregnancy and were hormonally regulated, none of these cytokines induced intrauterine HDC mRNA expression. The data suggest that progesterone is involved in the regulation of HDC mRNA expression in the preimplantation uterus, but IL-1alpha/beta, MCP-1 and RANTES, which have been reported to regulate histamine synthesis during inflammatory processes, do not appear to play a role.     

细胞周期蛋白D3在兔妊娠早期子宫和胚胎中的表达与调节

利用免疫组织化学及RT—PCR的方法,研究了细胞周期蛋白D3(Cyclin D3)在兔早期妊娠子宫和着床前胚胎中的表达情况,以揭示CyclinD3在兔胚胎着床过程中的可能作用。结果显示：(1)在兔妊娠第3～8天的子宫近肌层的腺上皮中有CyclinD3免疫染色,并且其表达强度在第7天以后呈现下降的趋势,着床的胚胎中未见CyclinD3免疫染色;(2)在第2～5天的假孕兔子宫的腺上皮中有较强的CyclinD3免疫染色;(3)在发情周期的兔子宫中未见其有表达;(4)在切除卵巢的兔中,注射雌激素后子宫中未见CyclinD3免疫染色,注射孕酮后在子宫腺上皮中有CyclinD3免疫染色,在孕酮和雌激素共同处理后的子宫腺上皮中有较强的CyclinD3免疫染色;(5)利用RT—PCR的方法在早期胚胎中均能检测到CyclinD3,但从胚泡期开始表达上升,到扩展胚泡时其表达最强。上述结果表明,CyclinD3的表达可能对兔胚泡的着床具有一定的调节作用。     

Decoding the chemokine network that links leukocytes with decidual cells and the trophoblast during early implantation

ABSTRACT

Chemokine network is central to the innate and adaptive immunity and entails a variety of proteins and membrane receptors that control physiological processes such as wound healing, angiogenesis, embryo growth and development. During early pregnancy, the chemokine network coordinates not only the recruitment of different leukocyte populations to generate the maternal-placental interface, but also constitutes an additional checkpoint for tissue homeostasis maintenance. The normal switch from a pro-inflammatory to an anti-inflammatory predominant microenvironment characteristic of the post-implantation stage requires redundant immune tolerance circuits triggered by key master regulators. In this review we will focus on the recruitment and conditioning of maternal immune cells to the uterus at the early implantation period with special interest on high plasticity macrophages and dendritic cells and their ability to induce regulatory T cells. We will also point to putative immunomodulatory polypeptides involved in immune homeostasis maintenance at the maternal-placental interface.     

Expression and hormonal regulation of calcyclin-binding protein (CacyBP) in the mouse uterus during early pregnancy

Calcyclin-binding protein (Siah-1-Interacting Protein, CacyBP/SIP), is a calcium signaling protein involved in the degradation of beta-catenin, however, little is known about its role in reproductive biology. The present study was to character its temporospatial expression pattern and regulation in mouse uterus and to investigate whether it plays a role in the regulation of normal endometrial events. While prominently expressed in both luminal and glandular epithelia, CacyBP underwent dynamic changes during early pregnancy. CacyBP expression was observed weakly from days 1-4. An intense accumulation in luminal and glandular epithelia as well as decidua surrounding the embryo at later stages (days 5-7) was observed. Most notably, CacyBP accumulation in trophoblast was pronounced at day 7. Using ovariectomized and pseudopregnant mice, we found that progesterone (P(4)) and 17beta-estradiol (E(2)) led to increased expression of CacyBP gene and this could be abolished by Ru486 and tamoxifen, respectively. Antisense oligonucleotides (ODNs) against CacyBP significantly inhibited cultured endometrial stromal cells' (ESCs) apoptosis induced by UV irradiation. Injection of antisense ODNs into mouse uterine horn severely impaired the number of implanted blastocysts. Taken together, our results suggested that CacyBP expression was positively regulated by P(4) and E(2). CacyBP may be involved in the regulation of endometrial cell apoptosis during early pregnancy and play an important role in mouse endometrial events such as pregrancy establishment.     

Interaction of mouse ectoplacental cone trophoblast and uterine decidua in vitro

Summary During the peri-implantation stages of mouse development, the secondary trophoblast invades into the uterine decidua. This uniquely controlled invasive process results in the formation of the placenta. We have analyzed this process in vitro using cultures of decidua and microdissected ectoplacental cones from Day 7 embryos. The results showed that the interaction between these two cell types is comparable to that seen in vivo. Morphologically, the decidua maintained close contact with the spreading trophoblast, limiting its invasion and producing a multilayered trophoblast outgrowth. Attachment to the decidua was not mediated through cell-matrix binding, but the subsequent invasion into the decidua was dependent on normal matrix interactions. Secretion of proteinases by the trophoblast also seemed to be a requirement for successful invasion, but not attachment.     

Expression of the orexin system in the porcine uterus,conceptus and trophoblast during early pregnancy

Orexin A and B are hypothalamic peptides derived from the prepro-orexin (PPO) precursor. Orexins stimulate food intake and arousal. Those peptides bind and activate two G protein-coupled receptors: orexin receptor 1 (OX1R) and orexin receptor 2 (OX2R). Numerous authors have suggested that orexins play an important role in the regulation of the reproductive functions. The objective of the present study was to analyse the presence of and changes in the gene and protein expression pattern of the orexin system in the porcine uterus, conceptus and trophoblast (chorioallantois) during early pregnancy. In the endometrium, the highest PPO and OX1R gene expression was detected on days 15 to 16 of gestation. The OX2R mRNA content in the endometrium was higher on days 10 to 11 and 15 to 16 than on days 12 to 13 and 27 to 28. In the trophoblasts, PPO gene expression was higher on days 30 to 32 than on days 27 to 28. The highest PPO protein content in the endometrium was noted on days 12 to 13. The highest OX1R protein content in the endometrium was detected on days 10 to 11, whereas OX2R protein on days 15 to 16. In the trophoblasts, PPO and OX1R protein levels were more pronounced on days 27 to 28 than on days 30 to 32, but OX2R expression was higher on days 30 to 32. The expression of PPO, OX1R and OX2R was different in the conceptuses and trophoblasts during early pregnancy. Local orexin production and the presence of the specific orexin receptors suggest that the orexin system may participate in the control of porcine reproductive functions by exerting endocrine and auto/paracrine effects on the uterus, conceptuses and trophoblasts during early pregnancy. This study provides the first evidence for the presence of orexins and their receptors in the uteri, conceptuses and trophoblasts in pigs during early pregnancy. The local orexin system is dependent on the stage of pregnancy.     

Expression and regulation of cytosolic prostaglandin E synthase in mouse uterus during the peri-implantation period

Prostaglandin E(2) (PGE(2)) is considered important for blastocyst spacing, implantation, and decidualization in rodent uteri. PGE synthase (PGES) catalyzes the isomerization of PGH(2) to PGE(2). Two isoforms of PGES exist: microsomal PGES (mPGES) and cytosolic PGES (cPGES); however, the expression and regulation of cPGES in the mammalian uterus during early pregnancy are still unknown. The aim of this study was to investigate the differential expression of cPGES in mouse uterus during early pregnancy and its regulation under different conditions using in situ hybridization and immunohistochemistry. A strong level of cPGES mRNA signal was exhibited in the stromal cells at the implantation site on Day 5 of pregnancy, whereas cPGES immunostaining was strongly detected in the luminal epithelium. The signals for both cPGES mRNA and immunostaining were strongly detected in the decidualized cells from Days 6-8 of pregnancy. A basal level of cPGES mRNA signal and immunostaining was exhibited in the uterus in delayed implantation. After delayed implantation was terminated by estrogen treatment and embryo implantation was initiated, cPGES mRNA signal was strongly detected in the stroma underlying the luminal epithelium at the implantation site, and cPGES immunostaining was strongly observed in the luminal epithelium surrounding the implanting blastocyst. A strong cPGES mRNA signal and immunostaining were detected in decidualized cells under artificial decidualization, whereas only a basal level of cPGES mRNA signal and immunostaining were observed in the control horn. Our data suggest that cPGES may play an important role during implantation and decidualization.     

Expression of mRNA encoding insulin‐like growth factors I and II by uterine tissues and placenta during pregnancy in the rat

The uterus and the placenta synthesize insulin‐like growth factors (IGFs) and insulin‐like binding proteins (IGFBPs). These growth factors are implicated in processes of proliferation and differentiation that occur in the uterus. To determine the patterns of expression of IGFs during rat pregnancy we used in situ hybridization with digoxigenin labeled probes on uterus from day 7 to day 16 of pregnancy. In early gestation days (7–8) both IGF mRNAs showed similar tissue distribution with relative abundance in the stroma and circular muscle layer. On days 11 and 12 expression for IGF‐I mRNA was found in the mesometrial decidua and metrial gland and in the ectoplacental cone while clear expression of IGF‐II mRNA could only be found in the latter. On days 13 and 14, expression for IGF‐I mRNA could be detected in the mesometrial decidua and metrial gland but no expression was observed for IGF‐II mRNA. A gradient of IGF‐I mRNA expression could be observed in the placenta on day 16, with the trophoblastic cells of the basal zone expressing the signal with stronger intensity than in the labyrinthine zone. For IGF‐II mRNA the highest expression was associated with the labyrinthine zone. Endovascular trophoblast was positive for both mRNAs. The spatial and temporal patterns of expression suggests a role for IGFs in the process of decidualization as well as in the establishment, growth and differentiation of the various trophoblast cells of the placenta. Mol. Reprod. Dev. 53:294–305, 1999. © 1999 Wiley‐Liss, Inc.     

Microarray analysis of cytokine and chemokine genes in the brains of macaques with SHIV-encephalitis

Human immunodeficiency virus (HIV)-encephalitis results from a cascade of viral-host interactions that lead to cytokine and chemokine imbalance, which then leads to neuropathologic manifestations of the disease. These include macrophage/microglia activation, astrocytosis and neuronal dysfunction or death. As the molecular mechanisms of this process are poorly understood, we used Atlas human cytokine or cytokine receptor microarray analysis to highlight gene expression profiles that accompanied encephalitis in Simian human immunodeficiency virus (SHIV) 89.6P-infected macaques. Of the 277 genes screened, marked upregulation of monocyte chemoattractant protein-1, interferon-inducible peptide IP-10 and interleukin-4 were observed specifically in the encephalitic brains. These genes are collectively known to promote macrophage infiltration and activation and virus replication. In contrast, genes regulating neurotrophic functions, such as brain-derived neurotrophic factor were downregulated. We also found that some of the apoptosis genes were up- or down-regulated. These data provide a comprehensive spectrum of gene expression that underscores the two major clinical manifestations of this unique syndrome: enhanced virus replication in brain macrophages and dystrophic changes in neurons.