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1.
Nat Rev Endocrinol ; 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601352

RESUMO

Pre-eclampsia and fetal growth restriction arise from disorders of placental development and have some shared mechanistic features. Initiation is often rooted in the maldevelopment of a maternal-placental blood supply capable of providing for the growth requirements of the fetus in later pregnancy, without exerting undue stress on maternal body systems. Here, we review normal development of a placental bed with a safe and adequate blood supply and a villous placenta-blood interface from which nutrients and oxygen can be extracted for the growing fetus. We consider disease mechanisms that are intrinsic to the maternal environment, the placenta or the interaction between the two. Systemic signalling from the endocrine placenta targets the maternal endothelium and multiple organs to adjust metabolism for an optimal pregnancy and later lactation. This signalling capacity is skewed when placental damage occurs and can deliver a dangerous pathogenic stimulus. We discuss the placental secretome including glycoproteins, microRNAs and extracellular vesicles as potential biomarkers of disease. Angiomodulatory mediators, currently the only effective biomarkers, are discussed alongside non-invasive imaging approaches to the prediction of disease risk. Identifying the signs of impending pathology early enough to intervene and ameliorate disease in later pregnancy remains a complex and challenging objective.

2.
Sci Rep ; 9(1): 14114, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575970

RESUMO

Diabetes mellitus (DM) during pregnancy can result in fetal overgrowth, likely due to placental dysfunction, which has health consequences for the infant. Here we test our prediction from previous work using a placental cell line that high glucose concentrations affect placental lipid metabolism. Placentas from women with type 1 (n = 13), type 2 (n = 6) or gestational (n = 12) DM, BMI-matched to mothers without DM (n = 18), were analysed for lipase and fatty acid transport proteins and fatty acid and triglyceride content. Explants from uncomplicated pregnancies (n = 6) cultured in physiological or high glucose were similarly analysed. High glucose levels did not alter placental lipase or transporter expression or the profile and abundance of fatty acids, but triglyceride levels were higher (p < 0.05), suggesting reduced ß- oxidation. DM did not affect placental protein expression or fatty acid profile. Triglyceride levels of placentas from mothers with pre-existing DM were similar to controls, but higher in obese women with gestational DM. Maternal hyperglycemia may not affect placental fatty acid uptake and transport. However, placental ß-oxidation is affected by high glucose and reduced in a subset of women with DM. Abnormal placental lipid metabolism could contribute to increased maternal-fetal lipid transfer and excess fetal growth in some DM pregnancies.

3.
Mol Hum Reprod ; 25(9): 572-585, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31418778

RESUMO

Fetal growth restriction (FGR) is caused by poor placental development and function early in gestation. It is well known that placentas from women with FGR exhibit reduced cell growth, elevated levels of apoptosis and perturbed expression of the growth factors, cytokines and the homeobox gene family of transcription factors. Previous studies have reported that insulin-like growth factor-2 (IGF2) interacts with its receptor-2 (IGF2R) to regulate villous trophoblast survival and apoptosis. In this study, we hypothesized that human placental IGF2R-mediated homeobox gene expression is altered in FGR and contributes to abnormal trophoblast function. This study was designed to determine the association between IGF2R, homeobox gene expression and cell survival in pregnancies affected by FGR. Third trimester placentas were collected from FGR-affected pregnancies (n = 29) and gestation matched with control pregnancies (n = 30). Functional analyses were then performed in vitro using term placental explants (n = 4) and BeWo trophoblast cells. mRNA expression was determined by real-time PCR, while protein expression was examined by immunoblotting and immunohistochemistry. siRNA transfection was used to silence IGF2R expression in placental explants and the BeWo cell-line. cDNA arrays were used to screen for downstream targets of IGF2R, specifically homeobox gene transcription factors and apoptosis-related genes. Functional effects of silencing IGF2R were then verified by ß-hCG ELISA, caspase activity assays and a real-time electrical cell-impedance assay for differentiation, apoptosis and cell growth potential, respectively. IGF2R expression was significantly decreased in placentas from pregnancies complicated by idiopathic FGR (P < 0.05 versus control). siRNA-mediated IGF2R knockdown in term placental explants and the trophoblast cell line BeWo resulted in altered expression of homeobox gene transcription factors, including increased expression of distal-less homeobox gene 5 (DLX5), and decreased expression of H2.0-Like Homeobox 1 (HLX) (P < 0.05 versus control). Knockdown of IGF2R transcription increased the expression and activity of caspase-6 and caspase-8 in placental explants, decreased BeWo proliferation and increased BeWo differentiation (all P < 0.05 compared to respective controls). This is the first study linking IGF2R placental expression with changes in the expression of homeobox genes that control cellular signalling pathways responsible for increased trophoblast cell apoptosis, which is a characteristic feature of FGR.

4.
Nanoscale ; 11(25): 12285-12295, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31211316

RESUMO

A complex combination of trafficking and signalling occurs at the surface of the placenta. The system delivers maternal nutrients to the fetus and facilitates gaseous exchange, whilst mediating signal transduction to support and stimulate the growth of the placenta itself. IGF-I is acknowledged as a maternally-derived ligand important in the regulation of placental growth. Here we show that quantum dots bearing IGF can stimulate IGF receptor (IGF1R) phosphorylation in the syncytio- (maternal-facing) and cyto- (fetal-facing) trophoblast bilayer that forms the outer boundary of the placenta, in a distribution similar to the one resulting from exposure to a soluble ligand. The conjugates are internalised by a clathrin-dependent pathway and delivered to a syncytioplasmic compartment that differs from conventional late endosomes and lysosomes. Two discrete downstream responses are evident in different cellular compartments: phosphorylation of P70S6K in the non-proliferative syncytiotrophoblast and of AKT in the cytotrophoblast. Co-conjugation of IGF-quantum dots with an RGD-containing ligand permits penetration beyond the syncytium, into the cytoplasm of the underlying cytotrophoblast. These data reveal the existence of a trans-syncytial pathway that allows maternal mitotic signals to penetrate to the inner progenitor cells, which must proliferate to support placental and consequently fetal growth.


Assuntos
Endocitose , Fator de Crescimento Insulin-Like I/metabolismo , Pontos Quânticos/química , Trofoblastos/metabolismo , Adulto , Feminino , Humanos , Gravidez , Trofoblastos/citologia
5.
Cells ; 8(5)2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075896

RESUMO

At the onset of pregnancy, embryo implantation is initiated by interactions between the endometrial epithelium and the outer trophectoderm cells of the blastocyst. Osteopontin (OPN) is expressed in the endometrium and is implicated in attachment and signalling roles at the embryo-epithelium interface. We have characterised OPN in the human endometrial epithelial Ishikawa cell line using three different monoclonal antibodies, revealing at least nine distinct molecular weight forms and a novel secretory pathway localisation in the apical domain induced by cell organisation into a confluent epithelial layer. Mouse blastocysts co-cultured with Ishikawa cell layers served to model embryo apposition, attachment and initial invasion at implantation. Exogenous OPN attenuated initial, weak embryo attachment to Ishikawa cells but did not affect the attainment of stable attachment. Notably, exogenous OPN inhibited embryonic invasion of the underlying cell layer, and this corresponded with altered expression of transcription factors associated with differentiation from trophectoderm (Gata2) to invasive trophoblast giant cells (Hand1). These data demonstrate the complexity of endometrial OPN forms and suggest that OPN regulates embryonic invasion at implantation by signalling to the trophectoderm.


Assuntos
Implantação do Embrião , Modelos Biológicos , Osteopontina/metabolismo , Animais , Anticorpos/farmacologia , Blastocisto/citologia , Blastocisto/metabolismo , Linhagem Celular Tumoral , Endométrio/citologia , Células Epiteliais/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos
6.
Reproduction ; 156(5): 421-428, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30131400

RESUMO

In vitro culture during assisted reproduction technologies (ART) exposes pre-implantation embryos to environmental stressors, such as non-physiological nutritional, oxidative and osmotic conditions. The effects on subsequent implantation are not well understood but could contribute to poor ART efficiency and outcomes. We have used exposure to hyperosmolarity to investigate the effects of stress on the ability of embryos to interact with endometrial cells in an in vitro model. Culturing mouse blastocysts for 2h in medium with osmolarity raised by 400mOsm induced blastocoel collapse and re-expansion, but did not affect subsequent attachment to, or invasion of, the endometrial epithelial Ishikawa cell line. Inhibition of stress-responsive c-Jun N-terminal kinase (JNK) activity with SP600125 did not affect the intercellular interactions between these embryos and the epithelial cells. Four successive cycles of hyperosmotic stress at E5.5 had no effect on attachment, but promoted embryonic breaching of the epithelial cell layer by trophoblast giant cells in a JNK-dependent manner. These findings suggest that acute stress at the blastocyst stage may promote trophoblast breaching of the endometrial epithelium at implantation, and implicates stress signalling through JNK in the process of trophectoderm differentiation into the invasive trophoblast necessary for the establishment of pregnancy. The data may lead to increased understanding of factors governing ART success rates and safety.


Assuntos
Implantação do Embrião , Animais , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Pressão Osmótica
7.
Placenta ; 64 Suppl 1: S2-S3, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29398014
8.
Endocrinology ; 159(2): 994-1004, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29244071

RESUMO

In pregnancy, resistance of endometrial decidual cells to stress signals is critical for the integrity of the fetomaternal interface and, by extension, survival of the conceptus. O-GlcNAcylation is an essential posttranslational modification that links glucose sensing to cellular stress resistance. Unexpectedly, decidualization of primary endometrial stromal cells (EnSCs) was associated with a 60% reduction in O-linked ß-N-acetylglucosamine (O-GlcNAc)‒modified proteins, reflecting downregulation of the enzyme that adds O-GlcNAc to substrates (O-GlcNAc transferase; OGT) but not the enzyme that removes the modification (O-GlcNAcase). Notably, epidermal growth factor domain-specific O-linked GlcNAc transferase (EOGT), an endoplasmic reticulum-specific OGT that modifies a limited number of secreted and membrane proteins, was markedly induced in differentiating EnSCs. Knockdown of EOGT perturbed a network of decidual genes involved in multiple cellular functions. The most downregulated gene upon EOGT knockdown in decidualizing cells was the energy homeostasis-associated gene (ENHO), which encodes adropin, a metabolic hormone involved in energy homeostasis and glucose and fatty acid metabolism. Analysis of midluteal endometrial biopsies revealed an inverse correlation between endometrial EOGT and ENHO expression and body mass index. Taken together, our findings revealed that obesity impairs the EOGT-adropin axis in decidual cells, which in turn points toward a mechanistic link between metabolic disorders and adverse pregnancy outcome.


Assuntos
Proteínas Sanguíneas/genética , Implantação do Embrião/genética , Endométrio/metabolismo , N-Acetilglucosaminiltransferases/fisiologia , Peptídeos/genética , Biópsia , Proteínas Sanguíneas/metabolismo , Índice de Massa Corporal , Células Cultivadas , Endométrio/enzimologia , Endométrio/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Infertilidade Feminina/complicações , Infertilidade Feminina/genética , Infertilidade Feminina/patologia , Obesidade/complicações , Obesidade/genética , Obesidade/patologia , Peptídeos/metabolismo , Gravidez , Complicações na Gravidez/genética , Complicações na Gravidez/patologia , Resultado da Gravidez/genética
9.
J Endocrinol ; 236(2): R93-R103, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29109081

RESUMO

Pregnancy is associated with significant changes in vitamin D metabolism, notably increased maternal serum levels of active vitamin D, 1,25-dihydroxyvitamin (1,25(OH)2D). This appears to be due primarily to increased renal activity of the enzyme 25-hydroxyvitamin D-1α-hydroxylase (CYP27B1) that catalyzes synthesis of 1,25(OH)2D, but CYP27B1 expression is also prominent in both the maternal decidua and fetal trophoblast components of the placenta. The precise function of placental synthesis of 1,25(OH)2D remains unclear, but is likely to involve localized tissue-specific responses with both decidua and trophoblast also expressing the vitamin D receptor (VDR) for 1,25(OH)2D. We have previously described immunomodulatory responses to 1,25(OH)2D by diverse populations of VDR-expressing cells within the decidua. The aim of the current review is to detail the role of vitamin D in pregnancy from a trophoblast perspective, with particular emphasis on the potential role of 1,25(OH)2D as a regulator of trophoblast invasion in early pregnancy. Vitamin D deficiency is common in pregnant women, and a wide range of studies have linked low vitamin D status to adverse events in pregnancy. To date, most of these studies have focused on adverse events later in pregnancy, but the current review will explore the potential impact of vitamin D on early pregnancy, and how this may influence implantation and miscarriage.


Assuntos
Implantação do Embrião/fisiologia , Placenta/fisiologia , Trofoblastos/fisiologia , Vitamina D/fisiologia , Animais , Feminino , Idade Gestacional , Humanos , Gravidez , Resultado da Gravidez , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/fisiopatologia
10.
Placenta ; 60: 1-8, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29208234

RESUMO

INTRODUCTION: Failure of trophoblast invasion and remodelling of maternal blood vessels leads to the pregnancy complication pre-eclampsia (PE). In other systems, the sphingolipid, sphingosine-1-phosphate (S1P), controls cell migration therefore this study determined its effect on extravillous trophoblast (EVT) function. METHODS: A transwell migration system was used to assess the behaviour of three trophoblast cell lines, Swan-71, SGHPL-4, and JEG3, and primary human trophoblasts in the presence or absence of S1P, S1P pathway inhibitors and 1,25(OH)2D3. QPCR and immunolocalisation were used to demonstrate EVT S1P receptor expression. RESULTS: EVTs express S1P receptors 1, 2 and 3. S1P inhibited EVT migration. This effect was abolished in the presence of the specific S1PR2 inhibitor, JTE-013 (p < 0.05 versus S1P alone) whereas treatment with the S1R1/3 inhibitor, FTY720, had no effect. In other cell types S1PR2 is regulated by vitamin D; here we found that treatment with 1,25(OH)2D3 for 48 or 72 h reduces S1PR2 (4-fold; <0.05), but not R1 and R3, expression. Moreover, S1P did not inhibit the migration of cells exposed to 1,25(OH)2D3 (p < 0.05). DISCUSSION: This study demonstrates that although EVT express three S1P receptor isoforms, S1P predominantly signals through S1PR2/Gα12/13 to activate Rho and thereby acts as potent inhibitor of EVT migration. Importantly, expression of S1PR2, and therefore S1P function, can be down-regulated by vitamin D. Our data suggest that vitamin D deficiency, which is known to be associated with PE, may contribute to the impaired trophoblast migration that underlies this condition.


Assuntos
Movimento Celular , Placentação , Receptores de Lisoesfingolipídeo/metabolismo , Trofoblastos/fisiologia , Vitamina D/fisiologia , Linhagem Celular , Feminino , Humanos , Lisofosfolipídeos/metabolismo , Gravidez , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato
11.
Mol Hum Reprod ; 23(9): 617-627, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28911212

RESUMO

STUDY QUESTION: How do interactions between blastocyst-stage embryos and endometrial epithelial cells regulate the early stages of implantation in an in vitro model? SUMMARY ANSWER: Mouse blastocyst apposition with human endometrial epithelial cells initiates trophectoderm differentiation to trophoblast, which goes on to breach the endometrial epithelium. WHAT IS KNOWN ALREADY: In vitro models using mouse blastocysts and human endometrial cell lines have proven invaluable in the molecular characterisation of embryo attachment to endometrial epithelium at the onset of implantation. Genes involved in embryonic breaching of the endometrial epithelium have not been investigated in such in vitro models. STUDY DESIGN, SIZE, DURATION: This study used an established in vitro model of implantation to examine cellular and molecular interactions during blastocyst attachment to endometrial epithelial cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: Mouse blastocysts developed from embryonic day (E) 1.5 in vitro were hatched and co-cultured with confluent human endometrial adenocarcinoma-derived Ishikawa cells in serum-free medium. A scale of attachment stability based on blastocyst oscillation upon agitation was devised. Blastocysts were monitored for 48 h to establish the kinetics of implantation, and optical sectioning using fluorescence microscopy revealed attachment and invasion interfaces. Quantitative PCR was used to determine blastocyst gene expression. Data from a total of 680 mouse blastocysts are reported, with 3-6 experimental replicates. T-test and ANOVA analyses established statistical significance at P < 0.05, P < 0.01 and P < 0.001. MAIN RESULTS AND THE ROLE OF CHANCE: Hatched E4.5 mouse blastocysts exhibited weak attachment to confluent Ishikawa cells over the first 24 h of co-culture, with intermediate and stable attachment occurring from 28 h (E5.5 + 4 h) in a hormone-independent manner. Attached embryos fixed after 48 h (E6.5) frequently exhibited outgrowths, characterised morphologically and with antibody markers as trophoblast giant cells (TGCs), which had breached the Ishikawa cell layer. Beginning co-culture at E5.5 also resulted in intermediate and stable attachment from E5.5 + 4 h; however, these embryos did not go on to breach the Ishikawa cell layer, even when co-culture was extended to E7.5 (P < 0.01). Blastocysts cultured from E4.5 in permeable transwell inserts above Ishikawa cells before transfer to direct co-culture at E5.5 went on to attach but failed to breach the Ishikawa cell layer by E6.5 (P < 0.01). Gene expression analysis at E5.5 demonstrated that direct co-culture with Ishikawa cells from E4.5 resulted in downregulation of trophectoderm transcription factors Cdx2 (P < 0.05) and Gata3 (P < 0.05) and upregulation of the TGC transcription factor Hand1 (P < 0.05). Co-culture with non-endometrial human fibroblasts did not alter the expression of these genes. LARGE SCALE DATA: None. LIMITATIONS, REASONS FOR CAUTION: The in vitro model used here combines human carcinoma-derived endometrial cells with mouse embryos, in which the cellular interactions observed may not fully recapitulate those in vivo. The data gleaned from such models can be regarded as hypothesis-generating, and research is now needed to develop more sophisticated models of human implantation combining multiple primary endometrial cell types with surrogate and real human embryos. WIDER IMPLICATIONS OF THE FINDINGS: This study implicates blastocyst apposition to endometrial epithelial cells as a critical step in trophoblast differentiation required for implantation. Understanding this maternal regulation of the embryonic developmental programme may lead to novel treatments for infertility. STUDY FUNDING AND COMPETING INTEREST(S): This work was supported by funds from the charities Wellbeing of Women (RG1442) and Diabetes UK (15/0005207), and studentship support for SCB from the Anatomical Society. No conflict of interest is declared.


Assuntos
Blastocisto/citologia , Implantação do Embrião/genética , Desenvolvimento Embrionário/genética , Células Epiteliais/citologia , Regulação da Expressão Gênica no Desenvolvimento , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Blastocisto/metabolismo , Fator de Transcrição CDX2/genética , Fator de Transcrição CDX2/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Técnicas de Cultura Embrionária , Endométrio/citologia , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Humanos , Camundongos , Transdução de Sinais
12.
Pediatr Res ; 80(2): 299-305, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27057740

RESUMO

BACKGROUND: Later life metabolic dysfunction is a well-recognized consequence of being born small for gestational age (SGA). This study has applied metabolomics to identify whether there are changes in these pathways in prepubertal short SGA children and aimed to compare the intracellular and extracellular metabolome in fibroblasts derived from healthy children and SGA children with postnatal growth impairment. METHODS: Skin fibroblast cell lines were established from eight SGA children (age 1.8-10.3 y) with failure of catch-up growth and from three healthy control children. Confluent cells were incubated in serum-free media and the spent growth medium (metabolic footprint), and intracellular metabolome (metabolic fingerprint) were analyzed by gas-chromatography mass spectrometry. RESULTS: Nineteen metabolites were significantly altered between SGA and control cell lines. The greatest fold difference (FD) was seen for alanine (fingerprint FD, SGA: control 0.3, P = 0.01 and footprint FD = 0.19, P = 0.01), aspartic acid (fingerprint FD = 5.21, P = 0.01), and cystine (footprint FD = 1.66, P = 0.02). Network analysis of the differentially expressed metabolites predicted inhibition of insulin as well as growth (ERK) signaling in SGA cells. CONCLUSION: This study indicates that changes in cellular metabolism associated with both growth failure and insulin insensitivity are present in prepubertal short children born SGA.


Assuntos
Aminoácidos/metabolismo , Glicólise , Transtornos do Crescimento/sangue , Recém-Nascido Pequeno para a Idade Gestacional , Alanina/metabolismo , Ácido Aspártico/metabolismo , Estatura , Criança , Pré-Escolar , Feminino , Fibroblastos/metabolismo , Idade Gestacional , Transtornos do Crescimento/complicações , Homozigoto , Humanos , Lactente , Insulina/metabolismo , Resistência à Insulina , Masculino , Metaboloma , Metabolômica , Mutação , Pele/metabolismo
13.
Am J Physiol Endocrinol Metab ; 310(1): E24-31, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26530156

RESUMO

Enhancing placental insulin-like growth factor (IGF) availability appears to be an attractive strategy for improving outcomes in fetal growth restriction (FGR). Our approach was the novel use of [Leu(27)]IGF-II, a human IGF-II analog that binds the IGF-II clearance receptor IGF-IIR in fetal growth-restricted (FGR) mice. We hypothesized that the impact of [Leu(27)]IGF-II infusion in C57BL/6J (wild-type) and endothelial nitric oxide synthase knockout (eNOS(-/-); FGR) mice would be to enhance fetal growth and investigated this from mid- to late gestation; 1 mg·kg(-1)·day(-1) [Leu(27)]IGF-II was delivered via a subcutaneous miniosmotic pump from E12.5 to E18.5. Fetal and placental weights recorded at E18.5 were used to generate frequency distribution curves; fetuses <5th centile were deemed growth restricted. Placentas were harvested for immunohistochemical analysis of the IGF system, and maternal serum was collected for measurement of exogenously administered IGF-II. In WT pregnancies, [Leu(27)]IGF-II treatment halved the number of FGR fetuses, reduced fetal(P = 0.028) and placental weight variations (P = 0.0032), and increased the numbers of pups close to the mean fetal weight (131 vs. 112 pups within 1 SD). Mixed-model analysis confirmed litter size to be negatively correlated with fetal and placental weight and showed that [Leu(27)]IGF-II preferentially improved fetal weight in the largest litters, as defined by number. Unidirectional (14C)MeAIB transfer per gram placenta (System A amino acid transporter activity) was inversely correlated with fetal weight in [Leu(27)]IGF-II-treated WT animals (P < 0.01). In eNOS(-/-) mice, [Leu(27)]IGF-II reduced the number of FGR fetuses(1 vs. 5 in the untreated group). The observed reduction in FGR pup numbers in both C57 and eNOS(-/-) litters suggests the use of this analog as a means of standardizing and rescuing fetal growth, preferentially in the smallest offspring.


Assuntos
Desenvolvimento Fetal/efeitos dos fármacos , Retardo do Crescimento Fetal/patologia , Fator de Crescimento Insulin-Like II/análogos & derivados , Animais , Modelos Animais de Doenças , Embrião de Mamíferos , Feminino , Retardo do Crescimento Fetal/tratamento farmacológico , Humanos , Fator de Crescimento Insulin-Like II/administração & dosagem , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo III/genética , Gravidez , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia
14.
Mol Hum Reprod ; 21(1): 105-14, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25304981

RESUMO

The rapid rise in obesity, metabolic syndrome and type 2 diabetes is one of the major healthcare problems of the Western world. Affected individuals are often treated with statins (3-hydroxy-3-methylglutaryl co-enzyme A [HMG CoA] reductase inhibitors) to reduce circulating cholesterol levels and the risk of developing cardiovascular disease; given the evolving demographic profile of these conditions, such drugs are increasingly prescribed to women of reproductive age. We have previously shown that exposure of placental tissue to statins inhibits the action of insulin-like growth factors (IGF)-I and -II which are key regulators of trophoblast proliferation and placental development. N-linked glycans in the IGF receptor, IGF1R, influence its presentation at the cell surface. This study aimed to determine whether statins, which are known to affect N-glycosylation, modulate IGF1R function in placenta. Treatment of first trimester villous tissue explants with statins (pravastatin or cerivastatin) or inhibitors of N-glycosylation (tunicamycin, deoxymannojirimycin or castanospermine) altered receptor distribution in trophoblast and attenuated proliferation induced by IGF-I or IGF-II (Ki67; P < 0.05, n = 5). Decreased binding of Phaseolus vulgaris lectin and phytohaemagglutinin to IGF1R immunoprecipitated from treated explants demonstrated reduced levels of complex N-linked glycans. Co-incubation of tissue explants with statins and farnesyl pyrophosphate (which increases the supply of dolichol intermediates), prevented statin-mediated disruption of IGF1R localization and reversed the negative effect on IGF-mediated trophoblast proliferation. These data suggest that statins attenuate IGF actions in the placenta by inhibiting N-linked glycosylation and subsequent expression of mature IGF1R at the placental cell surface.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Placenta/efeitos dos fármacos , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Feminino , Glicosilação/efeitos dos fármacos , Humanos , Placenta/metabolismo , Pravastatina/farmacologia , Gravidez , Primeiro Trimestre da Gravidez , Piridinas/farmacologia
15.
Endocrinology ; 156(1): 360-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25353183

RESUMO

Mice heterozygous for a signaling-deficient leptin receptor (Leprdb/+ [db/+]) are widely used as a model of gestational diabetes that results in poor fetal outcomes. This study investigated the importance of fetal genotype (db/+) relative to abnormal maternal metabolism for placental function and therefore fetal growth and offspring health. Wild-type (WT) and db/+ females were mated to db/+ and WT males, respectively, generating litters of mixed genotype. Placentas and fetuses were weighed at embryonic day 18.5; offspring weight, hormone levels, glucose tolerance, and blood pressure were assessed at 3 and 6 months. Pregnant db/+, but not WT, dams had impaired glucose tolerance. The db/+ placentas and fetuses were heavier than WT, but the maternal environment had no effect; WT placentas/fetuses from db/+ mothers were no bigger than WT placentas/fetuses carried by WT mothers. Postnatal weight gain, glucose metabolism, and leptin levels were all influenced by offspring genotype. However, maternal environment affected aspects of offspring health because WT male offspring born to db/+ dams were heavier and had worse glucose tolerance than the sex-matched WT offspring of WT mothers. Blood pressure was not affected by maternal or offspring genotype. These data reveal that studies using the db/+ mouse to model outcomes of pregnancy complicated by gestational diabetes should be mindful of the genetically predisposed fetal/postnatal overgrowth. Although inappropriate for dissecting the effect of maternal hyperglycemia on the contribution of placental function to macrosomia, the db/+ mouse may prove useful for investigating mechanisms underlying programming of suboptimal postnatal weight gain and glucose metabolism by an adverse maternal metabolic environment.


Assuntos
Diabetes Gestacional/metabolismo , Desenvolvimento Fetal/genética , Intolerância à Glucose/genética , Placentação , Receptores para Leptina/metabolismo , Ganho de Peso/genética , Animais , Feminino , Genótipo , Masculino , Camundongos , Gravidez , Receptores para Leptina/genética
16.
J Biol Chem ; 289(44): 30404-16, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25077964

RESUMO

Placental cell growth depends on an adaptable combination of an endogenous developmental program and the exogenous influence of maternal growth factors, both of which may be influenced by microRNA (miR)-dependent effects on gene expression. We have previously shown that global miR suppression in placenta accelerates proliferation and enhances levels of growth factor signaling mediators in cytotrophoblast. This study aimed to identify miRs involved in regulating placental growth. An initial array revealed 58 miR species whose expression differs between first trimester, when cytotrophoblast proliferation is rapid, and term, by which time proliferation has slowed. In silico analysis defined potential growth-regulatory miRs; among these, hsa-miR-145, hsa-miR-377, and hsa-let-7a were predicted to target known placental growth genes and were higher at term than in the first trimester, so they were selected for further analysis. Overexpression of miR-377 and let-7a, but not miR-145, in first trimester placental explants significantly reduced basal cytotrophoblast proliferation and expression of ERK and MYC. PCR arrays, in silico analysis, Western blotting, and 3'-UTR luciferase reporter assays revealed targets of miR-145 within the insulin-like growth factor axis. Analysis of proliferation in placental explants overexpressing miR-145 demonstrated its role as a mediator of insulin-like growth factor-induced trophoblast proliferation. These findings identify miR-377 and let-7a in regulation of endogenous cell growth and miR-145 in the placental response to maternal stimulation and will aid the development of therapeutic strategies for problem pregnancies.


Assuntos
MicroRNAs/fisiologia , Mitose/genética , Trofoblastos/fisiologia , Linhagem Celular , Proliferação de Células , Feminino , Redes Reguladoras de Genes , Humanos , Placenta/citologia , Placenta/metabolismo , Gravidez , Primeiro Trimestre da Gravidez , Interferência de RNA , Transdução de Sinais , Somatomedinas/fisiologia , Transcriptoma
17.
Depress Anxiety ; 31(8): 631-40, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24788589

RESUMO

BACKGROUND: Antenatal depression and anxiety are associated with adverse obstetric and mental health outcomes, yet practicable nonpharmacological therapies, particularly for the latter, are lacking. Yoga incorporates relaxation and breathing techniques with postures that can be customized for pregnant women. This study tested the efficacy of yoga as an intervention for reducing maternal anxiety during pregnancy. METHODS: Fifty-nine primiparous, low-risk pregnant women completed questionnaires assessing state (State Trait Anxiety Inventory; STAI-State), trait (STAI-Trait), and pregnancy-specific anxiety (Wijma Delivery Expectancy Questionnaire; WDEQ) and depression (Edinburgh Postnatal Depression Scale; EPDS) before randomization (baseline) to either an 8-week course of antenatal yoga or treatment-as-usual (TAU); both groups repeated the questionnaires at follow-up. The yoga group also completed pre- and postsession state anxiety and stress hormone assessments at both the first and last session of the 8-week course. RESULTS: A single session of yoga reduced both subjective and physiological measures of state anxiety (STAI-S and cortisol); and this class-induced reduction in anxiety remained at the final session of the intervention. Multiple linear regression analyses identified allocation to yoga as predictive of greater reduction in WDEQ scores (B = -9.59; BCa 95% CI = -18.25 to -0.43; P = .014; d = -0.57), while allocation to TAU was predictive of significantly increased elevation in EPDS scores (B = -3.06; BCa 95% CI = -5.9 to -0.17; P = .042; d = -0.5). No significant differences were observed in state or trait anxiety scores between baseline and follow-up. CONCLUSION: Antenatal yoga seems to be useful for reducing women's anxieties toward childbirth and preventing increases in depressive symptomatology.


Assuntos
Ansiedade/terapia , Depressão/terapia , Complicações na Gravidez/terapia , Ioga , Adulto , Ansiedade/metabolismo , Ansiedade/psicologia , Feminino , Humanos , Hidrocortisona/metabolismo , Gravidez , Segundo Trimestre da Gravidez/metabolismo , Segundo Trimestre da Gravidez/psicologia , Terceiro Trimestre da Gravidez/metabolismo , Terceiro Trimestre da Gravidez/psicologia , Resultado do Tratamento
18.
Mol Hum Reprod ; 20(5): 433-41, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24356876

RESUMO

The discrete regulation of vascular tone in the human uterine and placental circulations is a key determinant of appropriate uteroplacental blood perfusion and pregnancy success. Humoral factors such as estrogen, which increases in the placenta and maternal circulation throughout human pregnancy, may regulate these vascular beds as studies of animal arteries have shown that 17ß-estradiol, or agonists of estrogen receptors (ER), can exert acute vasodilatory actions. The aim of this study was to compare how acute exposure to ER-specific agonists, and 17ß-estradiol, altered human placental and uterine arterial tone in vitro. Uterine and placental arteries were isolated from biopsies obtained from women with uncomplicated pregnancy delivering a singleton infant at term. Vessels were mounted on a wire myograph, exposed to the thromboxane receptor agonist U46619 (10(-6) M), and then incubated with incremental doses (5 min, 0.03-30 µM) of either 17ß-estradiol or agonists specific for the ERs ERα (PPT), ERß (DPN) or the G-protein-coupled estrogen receptor GPER-1 (G1). ERα and ERß mRNA expression was assessed. 17ß-estradiol, PPT and DPN each relaxed myometrial arteries (P < 0.05) in a manner that was partly endothelium-dependent. In contrast, 17ß-estradiol or DPN relaxed placental arteries (maximum relaxation to 42 ± 1.1 or 47.6 ± 6.53% of preconstriction, respectively) to a lesser extent than myometrial arteries (to 0.03 ± 0.03 or 8.0 ± 1.0%) and in an endothelial-independent manner whereas PPT was without effect. G1 exposure did not inhibit the constriction of myometrial nor placenta arteries. mRNA expression of ERα and ERß was greater in myometrial arteries than placental arteries. ER-specific agonists, and 17ß-estradiol, differentially modulate the tone of uterine versus placental arteries highlighting that estrogen may regulate human uteroplacental blood flow in a tissue-specific manner.


Assuntos
Estradiol/farmacologia , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/efeitos dos fármacos , Estrogênios/farmacologia , Placenta/irrigação sanguínea , Artéria Uterina/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Agonistas dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Óxido Nítrico/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Artéria Uterina/metabolismo
19.
Mol Cell Proteomics ; 12(11): 3148-59, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23897580

RESUMO

Pre-eclampsia (PE) is a serious complication of pregnancy with potentially life threatening consequences for both mother and baby. Presently there is no test with the required performance to predict which healthy first-time mothers will go on to develop PE. The high specificity, sensitivity, and multiplexed nature of selected reaction monitoring holds great potential as a tool for the verification and validation of putative candidate biomarkersfor disease states. Realization of this potential involves establishing a high throughput, cost effective, reproducible sample preparation workflow. We have developed a semi-automated HPLC-based sample preparation workflow before a label-free selected reaction monitoring approach. This workflow has been applied to the search for novel predictive biomarkers for PE. To discover novel candidate biomarkers for PE, we used isobaric tagging to identify several potential biomarker proteins in plasma obtained at 15 weeks gestation from nulliparous women who later developed PE compared with pregnant women who remained healthy. Such a study generates a number of "candidate" biomarkers that require further testing in larger patient cohorts. As proof-of-principle, two of these proteins were taken forward for verification in a 100 women (58 PE, 42 controls) using label-free SRM. We obtained reproducible protein quantitation across the 100 samples and demonstrated significant changes in protein levels, even with as little as 20% change in protein concentration. The SRM data correlated with a commercial ELISA, suggesting that this is a robust workflow suitable for rapid, affordable, label-free verification of which candidate biomarkers should be taken forward for thorough investigation. A subset of pregnancy-specific glycoproteins (PSGs) had value as novel predictive markers for PE.


Assuntos
Glicoproteínas/sangue , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/diagnóstico , Proteínas da Gravidez/sangue , Proteômica/métodos , Adolescente , Adulto , Sequência de Aminoácidos , Automação , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Estudos de Coortes , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática , Feminino , Glicoproteínas/genética , Humanos , Dados de Sequência Molecular , Gravidez , Proteínas da Gravidez/genética , Segundo Trimestre da Gravidez/sangue , Estudos Prospectivos , Espectrometria de Massas em Tandem , Fluxo de Trabalho , Adulto Jovem , beta-Tromboglobulina/análise , beta-Tromboglobulina/genética
20.
J Clin Endocrinol Metab ; 97(11): E2098-104, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22948758

RESUMO

CONTEXT: Discrete regulation of the uterine and placental vasculatures is an important feature of uteroplacental perfusion and pregnancy success because appropriate maternal/fetal exchange of nutrients and gases is crucial for normal fetal growth. Placental vasculature lacks autonomic innervation so tone is controlled by locally derived vasoactive factors. IGF-I, which is produced by the placenta, is critical for normal fetal growth and studies of animal vascular systems have shown that IGF-I regulates vasomotor tone. OBJECTIVE: The objective of the study was to determine whether IGF-I directly alters human placental and myometrial arterial tone in vitro. PARTICIPANTS: Women with uncomplicated pregnancy delivering a singleton infant at term participated in the study. SETTING: The study was conducted at university hospital laboratories. MAIN OUTCOME MEASURE(S): Comparison of arterial tension measured before and after exposure to IGF-I. DESIGN: Placental and myometrial arteries were mounted on a wire myograph, exposed to the constrictor U46619 (10(-10) to 10(-5) m), returned to baseline tension, and then incubated with IGF-I (0-500 ng/ml) for various time points before performing a second dose-response curve to U46619. IGF-I receptor protein expression was assessed. RESULTS: IGF-I did not acutely alter the response of placental arteries to U46619. Exposure of myometrial arteries to IGF-I caused a rightward shift of U46619 dose-response curves (P < 0.05); EC(50) data were significantly increased at 30 (15.5 ± 2.8 vs. 133 ± 44 nm, before and after IGF treatment, respectively) and 60 min (10.9 ± 1.9 vs. 146 ± 47 nm). Placental and myometrial arteries had a similar IGF-I receptor expression profile. CONCLUSIONS: IGF-I acutely modulates the vasomotor tone of human myometrial, but not placental, arteries, suggesting that IGF-I regulates the delivery of maternal blood to the placenta.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Placenta/irrigação sanguínea , Artéria Uterina/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Adulto , Feminino , Humanos , Placenta/efeitos dos fármacos , Placenta/metabolismo , Gravidez , Receptor IGF Tipo 1/metabolismo , Artéria Uterina/metabolismo , Artéria Uterina/fisiologia , Vasoconstrição/fisiologia , Vasoconstritores/farmacologia
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