Search

Aims: To describe the temporal trends in Escherichia coli pathotypes and antimicrobial resistance detected in isolates from diseased-pig cases submitted to the EcL from 2008 to 2016, in Quebec, Canada, and to investigate the presence of spatiotemporal and phylogenetic clusters., Methods and Results: Detection of 12 genes coding for virulence factors in pathogenic E. coli in pigs by PCR and antimicrobial resistance standard disc diffusion assay were performed. Demographic and clinical data were entered in the Animal Pathogenic and Zoonotic E. coli (APZEC) database. ETEC:F4 was the most prevalent pathovirotype among the 3773 cases submitted. The LT:STb:F4 virotype was predominant until 2014, then was overtaken by the LT:STb:STa:F4 virotype. More than 90% of the ETEC:F4 isolates were multidrug resistant. A spatiotemporal cluster of LT:STb:STa:F4 isolates non-susceptible to enrofloxacin was detected between 4/2015 and 9/2016. Pulsed-field gel electrophoresis analysis of 137 ETEC:F4 isolates revealed the presence of a cluster composed mainly of LT:STb:STa:F4 isolates non-susceptible to enrofloxacin., Conclusions: The APZEC database was useful to highlight temporal trends in E. coli pathotypes. A high-risk ETEC:F4 clone might disseminate in the pig population in Quebec since 2015., Significance and Impact of the Study: Surveillance is crucial to identify new clones and develop control strategies., (© 2020 The Authors. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of Society for Applied Microbiology.)

Successful pregnancies rely on sufficient energy and nutrient supply, which require the mother to metabolically adapt to support fetal needs. The placenta has a critical role in this process, as this specialized organ produces hormones and peptides that regulate fetal and maternal metabolism. The ability for the mother to metabolically adapt to support the fetus depends on maternal prepregnancy health. Two-thirds of pregnancies in the United States involve obese or overweight women at the time of conception. This poses significant risks for the infant and mother by disrupting metabolic changes that would normally occur during pregnancy. Despite well characterized functions of placental hormones, there is scarce knowledge surrounding placental endocrine regulation of maternal metabolic trends in pathological pregnancies. In this review, we discuss current efforts to close this gap of knowledge and highlight areas where more research is needed. As the intrauterine environment predetermines the health and wellbeing of the offspring in later life, adequate metabolic control is essential for a successful pregnancy outcome. Understanding how placental hormones contribute to aberrant metabolic adaptations in pathological pregnancies may unveil disease mechanisms and provide methods for better identification and treatment. Studies discussed in this review were identified through PubMed searches between the years of 1966 to the present. We investigated studies of normal pregnancy and metabolic disorders in pregnancy that focused on energy requirements during pregnancy, endocrine regulation of glucose metabolism and insulin resistance, cholesterol and lipid metabolism, and placental hormone regulation., (© Endocrine Society 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Insufficient perfusion of the trophoblast by maternal blood is associated with an increased generation of reactive oxygen species and complications of the placenta. In this study, we first examined whether rosiglitazone, an agonist of the peroxisome proliferator-activated receptor-γ (PPARγ), protects the human trophoblast from oxidative injury by regulating key antioxidant proteins, catalase (CAT) and the superoxide dismutases (SOD1 and SOD2). In first trimester placental explants, localization of CAT was limited to cytotrophoblasts, whereas SOD1 was expressed in both the cyto- and syncytiotrophoblasts. In first trimester placental explants, hypoxia decreased the expression of both SOD1 and SOD2, and increased apoptosis. Treatment with rosiglitazone dose-dependently upregulated anti-oxidative CAT and SOD2, and rescued hypoxic injury in first trimester villous explants and JEG-3 cells, strongly suggesting the involvement of the PPARγ in regulating their expressions. Rosiglitazone facilitated transcription activity of PPARγ, and enhanced promotor binding, increased transcriptional activity at the CAT promoter, and elevated protein expression/activity. Treatment of hypoxic JEG-3 cells with rosiglitazone resulted in mitochondrial membrane potential increase and a reduction of caspase 9 and caspase 3 activity which is consistent with improved cell survival. To complement PPARγ activation data, we also utilized the antagonist (SR-202) and siRNA to suppress PPARγ expression and demonstrate the specific role of PPARγ in reducing ROS and oxidative stress. Ex vivo examination of term human placenta revealed lower expression of antioxidant proteins in pathologic compared to healthy placental tissues, which could be rescued by rosiglitazone, indicating that rosiglitazone can improve survival of the trophoblast under pathological conditions. These findings provide evidence that the PPARγ pathway directly influences cellular antioxidants production and the pathophysiology of placental oxidative stress., (© The Author(s) 2018. Published by Oxford University Press on behalf of Society for the Study of Reproduction.)

Study Question: Does low molecular weight heparin (LMWH) require heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF) signaling to induce extravillous trophoblast differentiation and decrease apoptosis during oxidative stress?, Summary Answer: LMWH increased HBEGF expression and secretion, and HBEGF signaling was required to stimulate trophoblast extravillous differentiation, increase invasion in vitro and reduce trophoblast apoptosis during oxidative stress., What Is Known Already: Abnormal trophoblast differentiation and survival contribute to placental insufficiency syndromes, including preeclampsia and intrauterine growth restriction. Preeclampsia often manifests as a pro-thrombotic state, with unsuccessful transformation of the spiral arteries that reduces oxygen supply and can produce placental infarction. LMWH improves placental function by increasing blood flow. Recent data suggest that the actions of LMWH transcend its anti-coagulative properties, but the molecular mechanism is unknown. There is evidence that LMWH alters the expression of human HBEGF in trophoblast cells, which regulates human trophoblast pathophysiology. HBEGF, itself, is capable of increasing trophoblast survival and invasiveness., Study Design, Size, Duration: First-trimester placental explants and the HTR-8/SVneo cell line, established using extravillous trophoblast outgrowths from first-trimester villous explants, were treated in vitro with LMWH to examine the effects on HBEGF signaling and trophoblast function under normal physiological and pathological conditions. A highly specific antagonist of HBEGF and other inhibitors of HBEGF downstream signaling were used to determine the relationship between LMWH treatment and HBEGF., Participants/materials, Setting, Methods: Placental tissues (n = 5) were obtained with IRB approval and patient consent from first-trimester terminations. Placental explants and HTR-8/SVneo cells were cultured on plastic or Matrigel™ and treated with a therapeutic dose of LMWH (Enoxaparin; 10 IU/ml), with or without CRM197, pan Erb-B2 Receptor Tyrosine Kinase (ERBB) inhibitor, anti-ERBB1 or ERBB4 blocking antibodies, or pretreatment of cells with heparitinase I. Extravillous differentiation was assessed by immunocytochemistry to determine the relative levels of integrins α6β4 and α1β1. Trophoblast invasiveness was assessed in villous explants by measuring outgrowth from villous tips cultured on Matrigel, and by invasion assays with HTR-8/SVneo cells cultured on Matrigel-coated transwell insert. Placental explants and HTR-8/SVneo cells were exposed to oxidative stress in a hypoxia-reoxygenation (H-R) model, measuring cell death by TUNEL assay, caspase 3 cleavage, and BCL-2α expression., Main Results and the Role of Chance: LMWH induced extravillous differentiation, according to trophoblast invasion assays and integrin (α6β4-α1β1) switching. Treatment with LMWH rescued cytotrophoblasts and HTR-8/SVneo cells from apoptosis during exposure to reoxygenation injury, based on TUNEL, caspase 3 cleavage and BCL-2α expression. Experiments using CRM197, ERBB1 and ERBB4 blocking antibodies, pan-ERBB inhibitor and removal of cell surface heparin demonstrated that the effects of LMWH on trophoblast invasion and survival were dependent upon HBEGF signaling., Large Scale Data: N/A., Limitations, Reasons for Caution: The primary limitation of this study was the use of only in vitro experiments. Patient demographics from elective terminations were not available., Wider Implications of the Findings: These data provide new insights into the non-coagulation-related aspects of perinatal LMWH treatment in the management of placental insufficiency disorders., Study Funding/competing Interest(s): This research was supported by grants from the National Institutes of Health (HD071408 and HL128628), the March of Dimes, and the W. K. Kellogg Foundation. There were no conflicts or competing interests., (© The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com)

Study Question: Is protein expression of the muscle segment homeobox gene family member MSX1 altered in the human secretory endometrium by cell type, developmental stage or fertility?, Summary Answer: MSX1 protein levels, normally elevated in the secretory phase endometrium, were significantly reduced in endometrial biopsies obtained from women of infertile couples., What Is Known Already: Molecular changes in the endometrium are important for fertility in both animals and humans. Msx1 is expressed in the preimplantation mouse uterus and regulates uterine receptivity for implantation. The MSX protein persists a short time, after its message has been down-regulated. Microarray analysis of the human endometrium reveals a similar pattern of MSX1 mRNA expression that peaks before the receptive period, with depressed expression at implantation. Targeted deletion of uterine Msx1 and Msx2 in mice prevents the loss of epithelial cell polarity during implantation and causes infertility., Study Design, Size Duration: MSX1 mRNA and cell type-specific levels of MSX1 protein were quantified from two retrospective cohorts during the human endometrial cycle. MSX1 protein expression patterns were compared between fertile and infertile couples. Selected samples were dual-labeled by immunofluorescence microscopy to localize E-cadherin and β-catenin in epithelial cells., Participants/materials, Setting Methods: MSX1 mRNA was quantified by PCR in endometrium from hysterectomies (n = 14) determined by endometrial dating to be in the late-proliferative (cycle days 10-13), early-secretory (cycle days 14-19) or mid-secretory (cycle days 20-24) phase. MSX1 protein was localized using high-throughput, semi-quantitative immunohistochemistry with sectioned endometrial biopsy tissues from fertile (n = 89) and infertile (n = 89) couples. Image analysis measured stain intensity specifically within the luminal epithelium, glands and stroma during the early-, mid- and late- (cycle days 25-28) secretory phases., Main Results and the Role of Chance: MSX1 transcript increased 5-fold (P < 0.05) between the late-proliferative and early secretory phase and was then down-regulated (P < 0.05) prior to receptivity for implantation. In fertile patients, MSX1 protein displayed strong nuclear localization in the luminal epithelium and glands, while it was weakly expressed in nuclei of the stroma. MSX1 protein levels accumulated throughout the secretory phase in all endometrial cellular compartments. MSX1 protein decreased (P < 0.05) in the glands between mid- and late-secretory phases. However, infertile patients demonstrated a broad reduction (P < 0.001) of MSX1 accumulation in all cell types throughout the secretory phase that was most pronounced (∼3-fold) in stroma and glands. Infertility was associated with persistent co-localization of E-cadherin and β-catenin in epithelial cell junctions in the mid- and late-secretory phases., Limitations, Reasons for Caution: Details of the infertility diagnoses and other patient demographic data were not available. Therefore, patients with uterine abnormalities (Mullerian) could not be distinguished from other sources of infertility. Antibody against human MSX2 is not available, limiting the study to MSX1. However, both RNAs in the human endometrium are similarly regulated. In mice, Msx1 and Msx2 are imperative for murine embryo implantation, with Msx2 compensating for genetic ablation of Msx1 through its up-regulation in a knockout model., Wider Implications of the Findings: This investigation establishes that the MSX1 homeobox protein accumulation is associated with the secretory phase in endometrium of fertile couples, and is widely disrupted in infertile patients. It is the first study to examine MSX1 protein localization in the human endometrium, and supported by genetic findings in mice, suggests that genes regulated by MSX1 are linked to the loss of epithelial cell polarity required for uterine receptivity during implantation., Study Funding/competing Interests: This research was supported by the NICHD National Cooperative Reproductive Medicine Network grant HD039005 (M.P.D.), NIH grants HD068524 (S.K.D.), HD071408 (D.R.A., M.P.D.), and HL128628 (S.D.), the Intramural Research Program of the NICHD, March of Dimes (S.K.D., S.D.) and JSPS KAKENHI grant 26112506 (Y.H.). There were no conflicts or competing interests., (© The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)