Cord blood myostatin concentrations by gestational diabetes mellitus and fetal sex.

Introduction: Myostatin is a member of the transforming growth factor β superfamily, and is mainly secreted from skeletal muscle. Animal studies have demonstrated that deficiency in myostatin promotes muscle growth and protects against insulin resistance. In humans, gestational diabetes mellitus (GDM) affects fetal insulin sensitivity.

EBF1-Correlated Long Non-coding RNA Transcript Levels in 3rd Trimester Maternal Blood and Risk of Spontaneous Preterm Birth.

Biomarkers associated with spontaneous preterm birth (sPTB) before labor onset could aid in prediction, triage, and stratification for testing interventions. In this study we examined maternal blood EBF1-correlated long non-coding RNAs (lncRNAs) in relation to sPTB. We retrieved all lncRNA transcripts from a public gene expression dataset (GSE59491) derived from maternal blood in trimesters 2 and 3 from a Canadian cohort with a matched set of sPTB (n = 51) and term births (n = 106).

Expression of severe acute respiratory syndrome coronavirus 2 cell entry genes, angiotensin-converting enzyme 2 and transmembrane protease serine 2, in the placenta across gestation and at the maternal-fetal interface in pregnancies complicated by preterm birth or preeclampsia.

Background: Although there is some evidence that severe acute respiratory syndrome coronavirus 2 can invade the human placenta, limited data exist on the gestational age-dependent expression profile of the severe acute respiratory syndrome coronavirus 2 cell entry mediators, angiotensin-converting enzyme 2 and transmembrane protease serine 2, at the human maternal-fetal interface. There is also no information as to whether the expression of these mediators is altered in pregnancies complicated by preeclampsia or preterm birth. This is important because the expression of decidual and placental angiotensin-converting enzyme 2 and transmembrane protease serine 2 across gestation may affect the susceptibility of pregnancies to vertical transmission of severe acute respiratory syndrome coronavirus 2.

Combinatorial extracellular matrix microarray identifies novel bioengineered substrates for xeno-free culture of human pluripotent stem cells.

Stem cells in their microenvironment are exposed to a plethora of biochemical signals and biophysical forces. Interrogating the role of each factor in the cell microenvironment, however, remains difficult due to the inability to study microenvironmental cues and tease apart their interactions in high throughput. To address this need, we developed an extracellular matrix (ECM) microarray screening platform capable of tightly controlling substrate stiffness and ECM protein composition to screen the effects of these cues and their interactions on cell fate.

Maternal blood -based microRNA transcripts as biomarkers for detecting risk of spontaneous preterm birth: a nested case-control study.

Objective: Both genetic variants and maternal blood mRNA levels of gene have been linked to sPTB. Animal and human studies suggest that specific -based miRNAs are involved in various physiological and pathophysiological processes. However, to date, we did not find any reports of -based miRNAs or miRNA transcripts in relation to sPTB.

EBF1 Gene mRNA Levels in Maternal Blood and Spontaneous Preterm Birth.

Genetic variants of six genes (EBF1, EEFSEC, AGTR2, WNT4, ADCY5, and RAP2C) have been linked recently to gestational duration and/or spontaneous preterm birth (sPTB). Our goal was to examine sPTB in relation to maternal blood mRNA levels of these genes. We used a public gene expression dataset (GSE59491) derived from maternal blood in trimesters 2 and 3 that included women with sPTB (n = 51) and term births (n = 106) matched for maternal age, race/ethnicity, pre-pregnancy body mass index, smoking during pregnancy, and parity.

Maternal malnutrition impacts placental morphology and transporter expression: an origin for poor offspring growth.

The placenta promotes fetal growth through nutrient transfer and selective barrier systems. An optimally developed placenta can adapt to changes in the pregnancy environment, buffering the fetus from adverse exposures. We hypothesized that the placenta adapts differently to suboptimal maternal diets, evidenced by changes in placental morphology, developmental markers and key transport systems.

MicroRNA-transcriptome networks in whole blood and monocytes of women undergoing preterm labour.

Preterm birth is attributed to neonatal morbidity as well as cognitive and physiological challenges. We have previously identified significant differences in mRNA expression in whole blood and monocytes, as well as differences in miRNA concentration in blood plasma, extracellular vesicles (EV) and EV-depleted plasma in women undergoing spontaneous preterm labour (sPTL). The goal of this analysis was to identify differences in miRNA expression within whole blood (WB) and peripheral monocytes (PM) from the same population of women undergoing sPTL compared with non-labouring controls matched by gestational age.

P-Glycoprotein (P-gp)/ABCB1 plays a functional role in extravillous trophoblast (EVT) invasion and is decreased in the pre-eclamptic placenta.

Dysregulation of trophoblast differentiation is implicated in the placental pathologies of intrauterine growth restriction and pre-eclampsia. P-glycoprotein (P-gp encoded by ABCB1) is an ATP-binding cassette transporter present in the syncytiotrophoblast layer of the placenta where it acts as a molecular sieve. In this study, we show that P-gp is also expressed in the proliferating cytotrophoblast (CT), the syncytiotrophoblast (ST) and the extravillous trophoblast (EVT), suggesting our hypothesis of a functional role for P-gp in placental development.

HIV antiretroviral exposure in pregnancy induces detrimental placenta vascular changes that are rescued by progesterone supplementation.

Adverse birth outcomes are common in HIV-positive pregnant women receiving combination antiretroviral therapy (cART), especially when cART is initiated in early pregnancy. The mechanisms remain poorly understood. Using a mouse model we demonstrate that protease inhibitor based-cART exposure beginning on day 1 of pregnancy was associated with a pro-angiogenic/pro-branching shift in the placenta driven by lower Flt-1 levels and higher Gcm-1 expression.

Comparative analysis of gene expression in maternal peripheral blood and monocytes during spontaneous preterm labor.

Background: Preterm birth is the leading cause of newborn death worldwide, and is associated with significant cognitive and physiological challenges in later life. There is a pressing need to define the mechanisms that initiate spontaneous preterm labor, and for development of novel clinical biomarkers to identify high-risk pregnancies. Most preterm birth studies utilize fetal tissues, and there is limited understanding of the transcriptional changes that occur in mothers undergoing spontaneous preterm labor.

Differentiating Mouse Embryonic Stem Cells into Embryoid Bodies in AggreWell Plates.

Embryonic stem (ES) cells can develop into many types of differentiated tissues if they are placed into a differentiating environment. This can occur in vivo when the ES cells are injected into or aggregated with an embryo, or in vitro if their culture conditions are modified to induce differentiation. Many times ES cell differentiation proceeds through an intermediate stage called the embryoid body (EB).

P-glycoprotein expression and localization in the rat uterus throughout gestation and labor.

Uterine tissues contain the efflux transporter P-glycoprotein (P-gp, encoded by Abcb1a/1b gene), but little is known about how it changes through gestation. Our aim was to investigate the expression profile and cellular localization of P-gp in the pregnant, laboring and post-partum (PP) rat uterus. We propose that during pregnancy the mechanical and hormonal stimuli play a role in regulating myometrial Abcb1a/1b/P-gp.

Generation and Use of Trophoblast Stem Cells and Uterine Myocytes to Study the Role of Connexins for Pregnancy and Labor.

Transgenic mouse models have demonstrated critical roles for gap junctions in establishing a successful pregnancy. To study the cellular and molecular mechanisms, the use of cell culture systems is essential to discriminate between the effects of different connexin isoforms expressed in individual cells or tissues of the developing conceptus or in maternal reproductive tissues. The generation and analysis of gene-deficient trophoblast stem cell lines from mice clearly revealed the functions of connexins in regulating placental development.

Quantitative large scale gene expression profiling from human stem cell culture micro samples using multiplex pre-amplification.

Transcriptional profiling is a powerful tool to study biological mechanisms during stem cell differentiation and reprogramming. Genome-wide methods like microarrays or next generation sequencing are expensive, time consuming, and require special equipment and bioinformatics expertise. Quantitative RT-PCR remains one of today's most widely accepted and used methods for analyzing gene expression in biological samples.

Physiological roles of connexins and pannexins in reproductive organs.

Reproductive organs are complex and well-structured tissues essential to perpetuate the species. In mammals, the male and female reproductive organs vary on their organization, morphology and function. Connectivity between cells in such tissues plays pivotal roles in organogenesis and tissue functions through the regulation of cellular proliferation, migration, differentiation and apoptosis.

Connexin31.1 (Gjb5) deficiency blocks trophoblast stem cell differentiation and delays placental development.

The gap junction channel forming connexins (Cx) Cx31 (Gjb3) and Cx31.1 (Gjb5) are co-expressed in the mouse trophoblast lineage. Inactivation of either gene results in partial embryonic loss at mid gestation (60% and 30%, respectively, between embryonic days E10.

DREAM mediated regulation of GCM1 in the human placental trophoblast.

The trophoblast transcription factor glial cell missing-1 (GCM1) regulates differentiation of placental cytotrophoblasts into the syncytiotrophoblast layer in contact with maternal blood. Reduced placental expression of GCM1 and abnormal syncytiotrophoblast structure are features of hypertensive disorder of pregnancy--preeclampsia. In-silico techniques identified the calcium-regulated transcriptional repressor--DREAM (Downstream Regulatory Element Antagonist Modulator)--as a candidate for GCM1 gene expression.

Connexin 31 (GJB3) deficiency in mouse trophoblast stem cells alters giant cell differentiation and leads to loss of oxygen sensing.

The nonphysiological placental oxidative environment has been implicated in many complications during human pregnancy. Oxygen tension can influence a broad spectrum of molecular changes leading to alterations in trophoblast cell lineage development. In this study, we report that mouse wild-type trophoblast stem cells (TSCs) react to low oxygen (3%) with an enhanced differentiation into the giant cell pathway, indicated by a downregulation of the early stem cell markers Eomes and Cdx2 as well as by a significant upregulation of Tfap2c and the differentiation markers Tpbpa and Prl3d1.

Transgene-free production of pluripotent stem cells using piggyBac transposons.

Reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) allows the derivation of -personalized stem cells. Transposon transgenesis is a novel and viable alternative to viral transduction methods for the delivery of reprogramming factors (Oct4, Sox2, Klf4, c-Myc) to somatic cells. Since transposons can be introduced as naked DNA using common plasmid transfection protocols, they provide a safer alternative to viral methods.

Human embryonic fibroblasts support single cell enzymatic expansion of human embryonic stem cells in xeno-free cultures.

The future application of human embryonic stem cells (hESC) for therapeutic approaches requires the development of xeno-free culture conditions to prevent the potential transmission of animal pathogens or xenobiotic substances to hESC. An important component of the majority of hESC culture systems developed is the requirement for fibroblasts to serve as feeders. For this purpose, several studies have used human foreskin fibroblasts established under xeno-free conditions.

Characterization of connexin31.1-deficient mice reveals impaired placental development.

The gap junction gene Connexin31.1 has been reported to be expressed predominantly in the epidermis of murine skin. To study the function of this gene, we generated mice in which the coding DNA of the Connexin31.

A sertoli cell-specific knockout of connexin43 prevents initiation of spermatogenesis.

The predominant testicular gap junctional protein connexin43 (cx43) is located between neighboring Sertoli cells (SCs) and between SCs and germ cells. It is assumed to be involved in testicular development, cell differentiation, initiation, and maintenance of spermatogenesis with alterations of its expression being correlated with various testicular disorders. Because total disruption of the cx43 gene leads to perinatal death, we generated a conditional cx43 knockout (KO) mouse using the Cre/loxP recombination system, which lacks the cx43 gene solely in SCs (SCCx43KO), to evaluate the SC-specific functions of cx43 on spermatogenesis in vivo.