240. Reduced endometrial angiogenesis during early pregnancy in relaxin-deficient mice

2008 ◽  
Vol 20 (9) ◽  
pp. 40
Author(s):  
J. E. Girling ◽  
L. Ng ◽  
L. J. Parry

Relaxin is a peptide hormone with important roles in the reproductive tract, including the growth and remodelling of endometrial vasculature. It has been shown to stimulate VEGF secretion from human endometrial stromal cells in vitro and increases endometrial vascularisation in ovariectomised steroid-primed primates in vivo. We have used mouse models to show that oestrogen and progesterone stimulate angiogenesis (new blood vessel growth) within the endometrium. Endometrial angiogenesis also occurs in the early stages of mouse pregnancy, which coincides with an increase in circulating progesterone. To date, no studies have investigated the effects of relaxin on endometrial angiogenesis in early pregnancy. Our aim was to test the hypothesis that endometrial angiogenesis would be reduced in relaxin-deficient mice (Rln−/−) in comparison to their wildtype (Rln+/+) counterparts. Uterine tissues were collected from Rln−/− and Rln+/+ mice on days 1 to 4 of pregnancy, before implantation. All mice were treated with BrdU before dissection to allow the number of blood vessel profiles containing proliferating endothelial cells (PVPs) to be quantified by double CD31/BrdU immunohistochemistry. Consistent with published studies, PVPs were first observed on days 3 and 4 of pregnancy. However, the percentage of PVPs was reduced in Rln−/− mice compared with Rln+/+ mice (Day 3: median = 4.4% v. 19.6%, Day 4: 9.6% v. 22.2%). We subsequently identified relaxin and relaxin receptors in the mouse endometrium in early pregnancy. Our data suggest that locally synthesised relaxin acts in synergy with progesterone to initiate endometrial angiogenesis in early pregnancy.

Reproduction ◽  
2010 ◽  
Vol 140 (5) ◽  
pp. 767-776 ◽  
Author(s):  
Anna J Korzekwa ◽  
Mamadou M Bah ◽  
Andrzej Kurzynowski ◽  
Karolina Lukasik ◽  
Agnieszka Groblewska ◽  
...  

Recently, we showed that leukotrienes (LTs) regulate ovarian cell functionin vitro. The aim of this study was to examine the role of LTs in corpus luteum (CL) function during both the estrous cycle and early pregnancyin vivo. mRNA expression of LT receptors (BLTfor LTB4andCYSLTfor LTC4), and 5-lipoxygenase (5-LO) in CL tissue and their localization in the ovary were studied during the estrous cycle and early pregnancy. Moreover, concentrations of LTs (LTB4and C4) in the CL tissue and blood were measured.5-LOandBLTmRNA expression increased on days 16–18 of the cycle, whereasCYSLTmRNA expression increased on days 16–18 of the pregnancy. The level of LTB4was evaluated during pregnancy compared with the level of LTC4, which increased during CL regression. LT antagonists influenced the duration of the estrous cycle: the LTC4antagonist (azelastine) prolonged the luteal phase, whereas the LTB4antagonist (dapsone) caused earlier luteolysisin vivo. Dapsone decreased progesterone (P4) secretion and azelastine increased P4secretion during the estrous cycle. In summary, LT action in the bovine reproductive tract is dependent on LT type: LTB4is luteotropic during the estrous cycle and supports early pregnancy, whereas LTC4is luteolytic, regarded as undesirable in early pregnancy. LTs are produced/secreted in the CL tissue, influence prostaglandin function, and serve as important factors during the estrous cycle and early pregnancy in cattle.


2005 ◽  
Vol 230 (3) ◽  
pp. 189-199 ◽  
Author(s):  
Izabela Wolawek-Potocka ◽  
Mamadou M. Bah ◽  
Anna Korzekwa ◽  
Mariusz K. Piskula ◽  
Wieslaw Wiczkowski ◽  
...  

Phytoestrogens acting as endocrine disruptors may induce various pathologies in the female reproductive tract. The purpose of this study was to determine whether phytoestrogens present in the soybean and/or their metabolites are detectable in the plasma of cows fed a diet rich in soy and whether these phytoestrogens influence reproductive efficiency and prostaglandin (PG) synthesis during the estrous cycle and early pregnancy in the bovine endometrium. In in vivo Experiment 1, we found significant levels of daidzein and genistein in the fodder and their metabolites (equol and p-ethyl-phenol) in bovine serum and urine. The mean number of artificial inseminations (Als) and pregnancy rates in two kinds of herds, control and experimental (cows fed with soybean 2.5 kg/day), were almost double in the soy-diet herd in comparison with the control animals. In in vivo Experiment 2, three out of five heifers fed soybean (2.5 kg/day) became pregnant whereas four out of five heifers in the control group became pregnant. The concentrations of a metabolite of PGF2α (PGFM) were significantly higher in the blood plasma of heifers fed a diet rich in soybean than those in the control heifers throughout the first 21 days after ovulation and AI. The higher levels of PGFM were positively correlated with equol and p-ethyl phenol concentrations in the blood. In in vitro experiments, the influence of isoflavones on PG secretion in different stages of the estrous cycle was studied. Although all phytoestrogens augmented the output of both PGs throughout the estrous cycle, equol and p-ethyl-phenol preferentially stimulated PGF2α output. The results obtained lead to the conclusion that soy-derived phytoestrogens and their metabolites disrupt reproductive efficiency and uterus function by modulating the ratio of PGF2α to PGE2, which leads to high, nonphysiological production of luteolytic PGF2α in cattle during the estrous cycle and early pregnancy.


2020 ◽  
Author(s):  
Ru-pin Alicia Chi ◽  
Tianyuan Wang ◽  
Chou-Long Huang ◽  
San-pin Wu ◽  
Steven Young ◽  
...  

AbstractWNK1 is an atypical kinase protein ubiquitously expressed in humans and mice. A mutation in its encoding gene causes hypertension in humans which is associated with abnormal ion homeostasis. Our earlier findings demonstrated that WNK1 is critical for in vitro decidualization in human endometrial stromal cells – pointing towards an unrecognized role of WNK1 in female reproduction. Here, we employed a mouse model with conditional WNK1 ablation from the female reproductive tract to define its in vivo role in uterine biology. Loss of WNK1 altered uterine morphology, causing endometrial epithelial hyperplasia, adenomyosis and a delay in embryo implantation, ultimately resulting in compromised fertility. Combining transcriptomic, proteomic and interactomic analyses revealed a novel regulatory pathway whereby WNK1 represses AKT phosphorylation through the phosphatase PP2A in endometrial cells from both humans and mice. We show that WNK1 interacts with PPP2R1A, an isoform of the PP2A scaffold subunit. This interaction stabilizes the PP2A complex, which then dephosphorylates AKT. Therefore, loss of WNK1 reduced PP2A activity, causing AKT hypersignaling. Using FOXO1 as a readout of AKT activity, we demonstrate that there was escalated FOXO1 phosphorylation and nuclear exclusion, leading to a disruption in the regulation of genes that are crucial for embryo implantation.


2021 ◽  
pp. 1-10
Author(s):  
Alireza Ghanavatinejad ◽  
Nesa Rashidi ◽  
Mahroo Mirahmadian ◽  
Simin Rezania ◽  
Mahdokht Mosalaei ◽  
...  

<b><i>Objectives:</i></b> Vitamin D has potent immunoregulatory features and modulates innate and adaptive immune responses. There is a significant association between intrauterine infection-associated inflammatory responses and pregnancy complications such as abortion and preterm labor. Here, we investigated how 1,25 (OH)2 D3 could modulate inflammatory responses of endometrial cells. <b><i>Design:</i></b> This is an in vitro experimental study. Endometrial stromal cells (ESCs) and whole endometrial cells (WECs) were collected from 15 apparently normal women, and the immunomodulatory effects of 1,25 (OH)2 D3 on lipopolysaccharide (LPS)- or lipoteichoic acid (LTA)-treated ESCs and WECs were investigated. <b><i>Participants/Materials, Setting, and Methods:</i></b> Women with no history of abortion, infertility, endometriosis, or sign of vaginal infection were enrolled in this study. Endometrial samples were collected by gynecologists using a Pipelle pipette in the proliferative phase of the menstrual cycle. WECs and ESCs were collected and treated with either LPS or LTA. The levels of IL-6, IL-8, and TNF-α in culture supernatants were quantified using the ELISA technique. TLR2, TLR4, and MyD88 expressions were assessed by RT-qPCR. TLR4 expression at the protein level was studied by the Western blot technique. <b><i>Results:</i></b> 1,25 Dihydroxycholecalciferol (1,25 (OH)2 D3) significantly reduced TNF-α production in LPS-activated ESCs and TNF-α and IL-6 production by LTA-stimulated WECs. In contrast, 1,25 (OH)2 D3 pretreatment increased the production of IL-8 by LPS- and LTA-stimulated endometrial cells. 1,25 (OH)2 D3 pretreatment markedly reduced LPS-induced TLR4 protein expression by ESCs. LPS treatment of ESCs significantly induced MyD88 gene expression. This effect was reversed when these cells were pretreated with 1,25 (OH)2 D3 before stimulation with LPS. <b><i>Limitations:</i></b> Because of the small size of samples, doing experiments all together on some samples was not feasible. Confirmation of the results obtained here needs well-designed in vivo studies. <b><i>Conclusions:</i></b> 1,25 (OH)2 D3 is an immunomodulatory molecule essential for maintaining endometrial immune homeostasis by controlling potentially harmful inflammatory responses associated with female reproductive tract infections.


Author(s):  
Alison Gartland ◽  
Katherine A. Buckley ◽  
Robert A. Hipskind ◽  
M. J. Perry ◽  
J. H. Tobias ◽  
...  

2020 ◽  
Vol 21 (10) ◽  
pp. 955-964 ◽  
Author(s):  
Mengjie Liu ◽  
John Wade ◽  
Mohammed Akhter Hossain

: Ghrelin is a 28-amino acid octanoylated peptide hormone that is implicated in many physiological and pathophysiological processes. Specific visualization of ghrelin and its cognate receptor using traceable ligands is crucial in elucidating the localization, functions, and expression pattern of the peptide’s signaling pathway. Here 12 representative radio- and fluorescently-labeled peptide-based ligands are reviewed for in vitro and in vivo imaging studies. In particular, the focus is on their structural features, pharmacological properties, and applications in further biochemical research.


2021 ◽  
Vol 22 (8) ◽  
pp. 4087
Author(s):  
Maria Quitério ◽  
Sandra Simões ◽  
Andreia Ascenso ◽  
Manuela Carvalheiro ◽  
Ana Paula Leandro ◽  
...  

Insulin is a peptide hormone with many physiological functions, besides its use in diabetes treatment. An important role of insulin is related to the wound healing process—however, insulin itself is too sensitive to the external environment requiring the protective of a nanocarrier. Polymer-based nanoparticles can protect, deliver, and retain the protein in the target area. This study aims to produce and characterize a topical treatment for wound healing consisting of insulin-loaded poly-DL-lactide/glycolide (PLGA) nanoparticles. Insulin-loaded nanoparticles present a mean size of approximately 500 nm and neutral surface charge. Spherical shaped nanoparticles are observed by scanning electron microscopy and confirmed by atomic force microscopy. SDS-PAGE and circular dichroism analysis demonstrated that insulin preserved its integrity and secondary structure after the encapsulation process. In vitro release studies suggested a controlled release profile. Safety of the formulation was confirmed using cell lines, and cell viability was concentration and time-dependent. Preliminary safety in vivo assays also revealed promising results.


Blood ◽  
1998 ◽  
Vol 92 (11) ◽  
pp. 3997-4002 ◽  
Author(s):  
Dirk Meyer ◽  
Carsten Schiller ◽  
Jürgen Westermann ◽  
Shozo Izui ◽  
Wouter L. W. Hazenbos ◽  
...  

Abstract In autoimmune hemolytic anemia (AIHA), there is accumulating evidence for an involvement of FcγR expressed by phagocytic effector cells, but demonstration of a causal relationship between individual FcγRs and IgG isotypes for disease development is lacking. Although the relevance of IgG isotypes to human AIHA is limited, we could show a clear IgG isotype dependency in murine AIHA using pathogenic IgG1 (105-2H) and IgG2a (34-3C) autoreactive anti–red blood cell antibodies in mice defective for FcγRIII, and comparing the clinical outcome to those in wild-type mice. FcγRIII-deficient mice were completely resistent to the pathogenic effects of 105-2H monoclonal antibody, as shown by a lack of IgG1-mediated erythrophagocytosis in vitro and in vivo. In addition, the IgG2a response by 34-3C induced a less severe but persistent AIHA in FcγRIII knock-out mice, as documented by a decrease in hematocrit. Blocking studies indicated that the residual anemic phenotype induced by 34-3C in the absence of FcγRIII reflects an activation of FcγRI that is normally coexpressed with FcγRIII on macrophages. Together these results show that the pathogenesis of AIHA through IgG1-dependent erythrophagocytosis is exclusively mediated by FcγRIII and further suggest that FcγRI, in addition to FcγRIII, contributes to this autoimmune disease when other IgG isotypes such as IgG2a are involved.


2017 ◽  
Vol 37 (5) ◽  
pp. 823-835 ◽  
Author(s):  
Christopher W. Smith ◽  
Steven G. Thomas ◽  
Zaher Raslan ◽  
Pushpa Patel ◽  
Maxwell Byrne ◽  
...  

Objective— Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is a collagen receptor that belongs to the inhibitory immunoreceptor tyrosine-based inhibition motif–containing receptor family. It is an inhibitor of signaling via the immunoreceptor tyrosine-based activation motif–containing collagen receptor complex, glycoprotein VI-FcRγ-chain. It is expressed on hematopoietic cells, including immature megakaryocytes, but is not detectable on platelets. Although the inhibitory function of LAIR-1 has been described in leukocytes, its physiological role in megakaryocytes and in particular in platelet formation has not been explored. In this study, we investigate the role of LAIR-1 in megakaryocyte development and platelet production by generating LAIR-1–deficient mice. Approach and Results— Mice lacking LAIR-1 exhibit a significant increase in platelet counts, a prolonged platelet half-life in vivo, and increased proplatelet formation in vitro. Interestingly, platelets from LAIR-1–deficient mice exhibit an enhanced reactivity to collagen and the glycoprotein VI–specific agonist collagen-related peptide despite not expressing LAIR-1, and mice showed enhanced thrombus formation in the carotid artery after ferric chloride injury. Targeted deletion of LAIR-1 in mice results in an increase in signaling downstream of the glycoprotein VI–FcRγ-chain and integrin αIIbβ3 in megakaryocytes because of enhanced Src family kinase activity. Conclusions— Findings from this study demonstrate that ablation of LAIR-1 in megakaryocytes leads to increased Src family kinase activity and downstream signaling in response to collagen that is transmitted to platelets, rendering them hyper-reactive specifically to agonists that signal through Syk tyrosine kinases, but not to G-protein–coupled receptors.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Tereza Cindrova-Davies ◽  
Xiaohui Zhao ◽  
Kay Elder ◽  
Carolyn J. P. Jones ◽  
Ashley Moffett ◽  
...  

AbstractAssessment of the endometrium often necessitates a biopsy, which currently involves an invasive, transcervical procedure. Here, we present an alternative technique based on deriving organoids from menstrual flow. We demonstrate that organoids can be derived from gland fragments recovered from menstrual flow. To confirm they faithfully reflect the in vivo state we compared organoids derived from paired scratch biopsies and ensuing menstrual flow from patients undergoing in vitro fertilisation (IVF). We demonstrate that the two sets of organoids share the same transcriptome signature, derivation efficiency and proliferation rate. Furthermore, they respond similarly to sex steroids and early-pregnancy hormones, with changes in morphology, receptor expression, and production of ‘uterine milk’ proteins that mimic those during the late-secretory phase and early pregnancy. This technique has wide-ranging impact for non-invasive investigation and personalised approaches to treatment of common gynaecological conditions, such as endometriosis, and reproductive disorders, including failed implantation after IVF and recurrent miscarriage.


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