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1.
Mol Hum Reprod ; 30(6)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38830032

RESUMO

Preterm birth is a serious pregnancy complication that affects neonatal mortality, morbidity, and long-term neurological prognosis. Predicting spontaneous preterm delivery (PTD) is important for its management. While excluding the risk of PTD is important, identifying women at high risk of PTD is imperative for medical intervention. Currently used PTD prediction parameters in clinical practice have shown high negative predictive values, but low positive predictive values. We focused on sulfated and sialylated glycocalyx changes in the uterus and vagina prior to the onset of parturition and explored the potential of electrophysiological detection of these changes as a PTD prediction parameter with a high positive predictive value. In vivo local vaginal bioelectrical impedance (VZ) was measured using two different mouse PTD models. PTD was induced in ICR mice through the subcutaneous injection of mifepristone or local intrauterine injection of lipopolysaccharide (LPS). The PTD rates were 100% and 60% post-administration of mifepristone (16-20 h, n = 4) and LPS (12-24 h, n = 20), respectively. The local VZ values (15 and 10 h after mifepristone or LPS treatment, respectively) were significantly lower in the PTD group than in the non-PTD group. Receiver operator characteristic (ROC) curve analysis of VZ at 125 kHz as a predictor of PTD showed an area under the ROC curve of 1.00 and 0.77 and positive predictive values of 1.00 and 0.86, for the mifepristone and LPS models, respectively, suggesting that local VZ value can predict PTD. Histological examination of the LPS-treated model 6 h post-treatment revealed increased expression of sulfomucins and/or sulfated proteoglycans and sialomucins in the cervical epithelium, cervical stroma and vaginal stroma. In conclusion, local VZ values can determine sulfated and sialylated glycocalyx alterations within the uterus and vagina and might be a useful PTD prediction parameter.


Assuntos
Impedância Elétrica , Camundongos Endogâmicos ICR , Nascimento Prematuro , Vagina , Animais , Feminino , Vagina/metabolismo , Vagina/efeitos dos fármacos , Vagina/patologia , Gravidez , Camundongos , Nascimento Prematuro/metabolismo , Nascimento Prematuro/diagnóstico , Mifepristona/farmacologia , Útero/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/toxicidade , Valor Preditivo dos Testes , Curva ROC , Modelos Animais de Doenças
2.
Reprod Domest Anim ; 56(1): 130-141, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33174273

RESUMO

Glycosylation of the reproductive tract of an adult female red-necked ostrich (Struthio camelus camelus) carrying a fully formed calcified egg in her uterus when accidently killed by a blow to the head was examined using lectin histochemistry on samples from the infundibulum, magnum, uterus and vagina. Glycans in the luminal epithelium and underlying glands were described after staining with 23 lectins after neuraminidase pre-treatment in some cases. Ciliated and non-ciliated cells were evident at all levels in the luminal epithelium, the latter full of richly glycosylated secretory granules. The ciliated cells also showed glycosylation and, in the magnum, these cells often stained more intensely than the non-ciliated cells. High mannose and complex N-glycans, α1,6-linked fucosyl and sialic acid residues were present throughout the tract and there was a complete absence of GalNAcα1,3(LFucα1,2)Galß1,3/4GlcNAcß1- and rare terminal GalNAcα1- residues. Fucose in α1,2-linkage as H2 antigen and Ley was also rare in the luminal epithelium and completely absent in glands. Terminal galactose was present in the luminal epithelium apart from in the infundibulum. Gland epithelium showed similar glycosylation to the luminal epithelium except in the magnum where there were significant differences and here the glands were packed full of large secretory granules, unlike the glands in the rest of the tract. Each section of the tract had its own specific pattern of glycosylation which could be related to the stage of egg formation.


Assuntos
Genitália Feminina/metabolismo , Polissacarídeos/metabolismo , Struthioniformes/metabolismo , Animais , Feminino , Glicosilação , Óvulo
3.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298913

RESUMO

Up to 11% of pregnancies extend to post-term with adverse obstetric events linked to pregnancies over 42 weeks. Oxidative stress and senescence (cells stop growing and dividing by irreversibly arresting their cell cycle and gradually ageing) can result in diminished cell function. There are no detailed studies of placental cell senescence markers across a range of gestational ages, although increased levels have been linked to pre-eclampsia before full term. This study aimed to determine placental senescence and oxidative markers across a range of gestational ages in women with uncomplicated pregnancies and those with a diagnosis of pre-eclampsia. Placentae were obtained from 37 women with uncomplicated pregnancies of 37-42 weeks and from 13 cases of pre-eclampsia of 31+2-41+2 weeks. The expression of markers of senescence, oxidative stress, and antioxidant defence (tumour suppressor protein p16INK4a, kinase inhibitor p21, interleukin-6 (IL-6), NADPH oxidase 4 (NOX4), glutathione peroxidases 1, 3, and 4 (GPx1, GPx3, and GPx4), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1)) genes was measured (quantitative real-time PCR). Protein abundance of p16INK4a, IL-6, NOX4, 8-hydroxy-2'-deoxy-guanosine (8-OHdG), and PlGF was assessed by immunocytochemistry. Placental NOX4 protein was higher in post-term than term deliveries and further increased by pre-eclampsia (p < 0.05 for all). P21 expression was higher in post-term placentae (p = 0.012) and in pre-eclampsia (p = 0.04), compared to term. Placental P16INK4a protein expression was increased post-term, compared to term (p = 0.01). In normotensive women, gestational age at delivery was negatively associated with GPx4 and PlGF (mRNA and protein) (p < 0.05 for all), whereas a positive correlation was seen with placental P21, NOX4, and P16INK4a (p < 0.05 for all) expression. Markers of placental oxidative stress and senescence appear to increase as gestational age increases, with antioxidant defences diminishing concomitantly. These observations increase our understanding of placental health and may contribute to assessment of the optimal gestational age for delivery.


Assuntos
Senescência Celular/fisiologia , Estresse Oxidativo/fisiologia , Placenta/fisiologia , Pré-Eclâmpsia/fisiopatologia , Adulto , Biomarcadores/metabolismo , Feminino , Idade Gestacional , Humanos , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Gravidez , Resultado da Gravidez , RNA Mensageiro/metabolismo
4.
5.
Hum Reprod ; 33(12): 2241-2248, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30329050

RESUMO

STUDY QUESTION: Can vaginal bioelectrical impedance (VZ) electrophysiologically determine alterations of the endometrium in preparation for implantation? SUMMARY ANSWER: VZ can electrophysiologically detect the sulfation and sialylation changes in the uterine glycocalyx in preparation for implantation. WHAT IS KNOWN ALREADY: Uterine receptivity is associated with various glycosylation changes that affect negative charge density at the luminal epithelial cell surface. VZ has been used to monitor the oestrous cycle. STUDY DESIGN, SIZE, DURATION: Pathogen-free Jcl:ICR mice, aged 8-10 weeks, were used in this study. We conducted the following three steps to test our hypothesis that VZ may be used to determine uterine receptivity. First, to investigate whether VZ could determine alteration of sulfation and sialylation in the uterine glycocalyx, VZ was measured in mice with induced artificial sulfation and sialylation changes in the uterine glycocalyx (galactose-3-O-sulfotransferase 2 (GP3ST) + α(1,3/1,4) fucosyltransferase gene (FucT-III)-transferred group (n = 15) and in LacZ (encoding for ß-galactosidase)-transferred mice as a control group (n = 12)). Second, to investigate whether VZ could determine alterations of the endometrium in preparation for implantation, we measured VZ during the early stage of pregnancy (n = 12 each). Third, to investigate whether VZ could be used to evaluate uterine receptivity prospectively, VZ was measured in an implantation failure model mice. In 21 mice, local and transient suppression of signal transducer and activator of transcription-3 (Stat3) in the uterus were evaluated 1 day before implantation began, and 23 scramble decoy-transferred mice were used as a control group. PARTICIPANTS/MATERIALS, SETTING, METHODS: The VZ was measured at a frequency of 1 kHz in Jcl:ICR mice. Data were analysed using the Kruskal-Wallis test with Dunn's multiple comparisons, or the Student's t-test or Wilcoxon's rank-sum test with the Shapiro-Wilk normality test. The values of VZ were analysed using receiver operating characteristic (ROC) curve analysis to identify the optimal cut-off point to determine if this parameter predicted non-pregnancy. MAIN RESULTS AND THE ROLE OF CHANCE: Sulfation and sialylation changes induced in the luminal epithelial glycocalyx decreased the value of VZ. VZ showed a significant daily decrease during the early stage of pregnancy (Day 1.5 versus 2.5 p.c.: P < 0.005; Student's t-test, Day 2.5 versus 3.5 p.c.: P < 0.001; Wilcoxon's rank-sum test, Day 3.5 versus 4.5 p.c.: P < 0.005; Student's t-test, Day 4.5 versus 5.5 p.c.: P < 0.05; Student's t-test). One day before implantation began, VZ in the implantation failure model mice was significantly higher than in the control mice (P < 0.001, Wilcoxon's rank-sum test). The ROC curve analysis of VZ as a predictor of non-conception showed areas under the ROC curve of 0.91 (95% CI: 0.83-0.99). LIMITATIONS, REASONS FOR CAUTION: Although it is influenced by surface charge in the uterine epithelium, the mechanism whereby VZ changes during early pregnancy is still unexplained. WIDER IMPLICATIONS OF THE FINDINGS: Local bioelectrical impedance may help to prospectively evaluate uterine receptivity in women. Including the measurement of local bioelectrical impedance as part of a frozen-thawed embryo transfer strategy may improve the efficiency of ART. STUDY FUNDING/COMPETING INTEREST(S): This work was supported in part by the Japan Society for the Promotion of Science JSPS KAKENHI Grant (Nos. 19390429, 21390453, 16K11086 and 16K11087) from the Ministry of Education, Science and Culture of Japan (Tokyo, Japan) and Suzuken Memorial Foundation (Nagoya, Japan). The authors declare that they have no conflict of interest.


Assuntos
Implantação do Embrião/fisiologia , Útero/fisiologia , Vagina/fisiologia , Animais , Impedância Elétrica , Feminino , Camundongos
6.
Diabetologia ; 59(10): 2240-50, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27406815

RESUMO

AIMS/HYPOTHESIS: The aim of this work was to determine whether placental endoplasmic reticulum (ER) stress may contribute to the pathophysiology of gestational diabetes mellitus (GDM) and to test the efficacy of chemical chaperones and antioxidant vitamins in ameliorating that stress in a trophoblast-like cell line in vitro. METHODS: Placental samples were obtained from women suffering from GDM and from normoglycaemic controls and were frozen immediately. Women with GDM had 2 h serum glucose levels > 9.0 mmol/l following a 75 g oral glucose tolerance test and were treated with diet and insulin when necessary. Western blotting was used to assess markers of ER stress. To test the effects of hyperglycaemia on the generation of ER stress, a new trophoblast-like cell line, BeWo-NG, was generated by culturing in a physiological glucose concentration of 5.5 mmol/l (over 20 passages) before challenging with 10 or 20 mmol/l glucose. RESULTS: All GDM patients were well-controlled (HbA1c 5.86 ± 0.55% or 40.64 ± 5.85 mmol/mol, n = 11). Low-grade ER stress was observed in the placental samples, with dilation of ER cisternae and increased phosphorylation of eukaryotic initiation factor 2 subunit α. Challenge of BeWo-NG with high glucose activated the same pathways, but this was as a result of acidosis of the culture medium rather than the glucose concentration per se. Addition of chemical chaperones 4-phenylbutyrate and tauroursodeoxycholic acid and vitamins C and E ameliorated the ER stress. CONCLUSIONS/INTERPRETATION: This is the first report of placental ER stress in GDM patients. Chemical chaperones and antioxidant vitamins represent potential therapeutic interventions for GDM.


Assuntos
Antioxidantes/uso terapêutico , Diabetes Gestacional/sangue , Diabetes Gestacional/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Placenta/metabolismo , Acidose/tratamento farmacológico , Adulto , Ácido Ascórbico/farmacologia , Glicemia/efeitos dos fármacos , Western Blotting , Linhagem Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Glucose/farmacologia , Humanos , Fenilbutiratos/farmacologia , Fosforilação/efeitos dos fármacos , Gravidez , Ácido Tauroquenodesoxicólico/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Vitamina E/farmacologia
7.
Mol Phylogenet Evol ; 83: 184-90, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25527317

RESUMO

The placenta of ruminants contains characteristic binucleate cells (BNC) with a highly conserved glycan structure which evolved early in Ruminant phylogenesis. Giraffe and Okapi placentae also contain these cells and it is not known whether they have a similar glycan array. We have used lectin histochemistry to examine the glycosylation of these cells in these species and compare them with bovine BNC which have a typical ruminant glycan composition. Two placentae, mid and near term, from Giraffe (Giraffa camelopardalis) and two term placenta of Okapi (Okapia johnstoni) were embedded in resin and stained with a panel of 23 lectins and compared with near-term bovine (Bos taurus) placenta. Significant differences were found in the glycans of Giraffe and Okapi BNC compared with those from the bovine, with little or no expression of terminal αN-acetylgalactosamine bound by Dolichos biflorus and Vicia villosa agglutinins which instead bound to placental blood vessels. Higher levels of N-acetylglucosamine bound by Lycopersicon esculentum and Phytolacca americana agglutinins were also apparent. Some differences between Okapi and Giraffe were evident. Most N-linked glycans were similarly expressed in all three species as were fucosyl residues. Interplacentomal areas in Giraffe and Bovine showed differences from the placentomal cells though no intercotyledonary BNC were apparent in Okapi. In conclusion, Giraffidae BNC developed different glycan biosynthetic pathways following their split from the Bovidae with further differences evolving as Okapi and Giraffe diverged from each other, affecting both inter and placentomal BNC which may have different functions during development.


Assuntos
Placenta/citologia , Polissacarídeos/química , Ruminantes/classificação , Acetilgalactosamina/química , Animais , Bovinos , Feminino , Glicosilação , Filogenia , Lectinas de Plantas , Gravidez
8.
Placenta ; 138: 109-112, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37262940

RESUMO

Endotheliochorial cat (Felis catus) and lion (Panthera leo) term placentae and one 6 week placenta (term 60-63 days) from a dog (Canis familiaris) were stained with a panel of 24 lectins to compare glycosylation at the feto-maternal interface. Glycan expression in lion and cat placentae was very similar apart from the occurrence of terminal α-galactose in the lion trophoblast. The dog differed in several respects, particularly in the trophoblast, consistent with species-specific glycotypes differing according to the degree of their evolutionary divergence. The data suggest that evolutionary effects on the glycotype are most readily observed in trophoblast.


Assuntos
Canidae , Leões , Gatos , Animais , Feminino , Gravidez , Cães , Placenta , Glicosilação , Trofoblastos
9.
Placenta ; 134: 30-38, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36868120

RESUMO

INTRODUCTION: Placental glycosylation has been examined on eight feline placentae ranging from approximately 15 to 60 days post-conception as little is known about changes in glycan distribution in this species. METHODS: Specimens were resin embedded and lectin histochemistry was applied to semi-thin sections using a panel of 24 lectins and an avidin-biotin revealing system. RESULTS: Abundant tri-tetraantennary complex N-glycan and α-galactosyl residues found in the syncytium in early pregnancy were greatly reduced in mid-pregnancy, though retained at the invasion front in the syncytium (N-glycan) or cytotrophoblast layer (αGal). Some other glycans were also uniquely present in invading cells. Abundant polylactosamine was found in the infolding basal lamina of syncytiotrophoblast and the apical villous cytotrophoblast membrane. Syncytial secretory granules often clustered near the apical membrane abutting maternal vessels. Decidual cells selectively expressed ß-galactosyl residues throughout pregnancy and highly branched N-glycan levels increased over time. DISCUSSION: Glycan distribution changes significantly over pregnancy, probably relating to the development of transport and invasive properties of trophoblast which in the endotheliochorial placenta reaches the level of the maternal vessels. Highly branched complex N-glycans, often associated with invasive cells, N-Acetylgalactosamine and terminal α-galactosyl residues are present at the invasion front abutting the junctional zone of the endometrium. Abundant polylactosamine on the syncytiotrophoblast basal lamina may reflect the presence of specialised adhesive interactions, while clustering of glycosylated granules apically is probably associated with secretion and absorption of material via maternal vasculature. It is suggested that lamellar and invasive cytotrophoblast represent distinct differentiation pathways. 246 words.


Assuntos
Placenta , Trofoblastos , Gravidez , Animais , Gatos , Feminino , Trofoblastos/metabolismo , Placenta/metabolismo , Placentação , Lectinas/análise , Polissacarídeos/metabolismo , Diferenciação Celular
10.
iScience ; 26(1): 105911, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36660474

RESUMO

Placental hormones orchestrate maternal metabolic adaptations to support pregnancy. We hypothesized that placental ER stress, which characterizes early-onset pre-eclampsia (ePE), compromises glycosylation, reducing hormone bioactivity and these maladaptations predispose the mother to metabolic disease in later life. We demonstrate ER stress reduces the complexity and sialylation of trophoblast protein N-glycosylation, while aberrant glycosylation of vascular endothelial growth factor reduced its bioactivity. ER stress alters the expression of 66 of the 146 genes annotated with "protein glycosylation" and reduces the expression of sialyltransferases. Using mouse placental explants, we show ER stress promotes the secretion of mis-glycosylated glycoproteins. Pregnant mice carrying placentas with junctional zone-specific ER stress have reduced blood glucose, anomalous hepatic glucose metabolism, increased cellular stress and elevated DNA methyltransferase 3A. Using pregnancy-specific glycoproteins as a readout, we also demonstrate aberrant glycosylation of placental proteins in women with ePE, thus providing a mechanistic link between ePE and subsequent maternal metabolic disorders.

11.
Glycobiology ; 22(4): 470-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22025012

RESUMO

A family of 13 fucosyltransferase genes has evolved to catalyze the addition of fucose in various linkage positions to nascent glycoproteins. Null mutations in mice are unearthing unsuspected functions for glycoprotein fucosylation that affect embryo implantation and growth of the conceptus. Furthermore, as we show here, histological studies demonstrate that a variety of fucosylated structures are found within the glycan-rich interface between trophectoderm and uterine epithelium. We suggest that conservation or change in fucosyltransferase gene expression over evolutionary time has played a role in determining the stability of the maternal-fetal interface and therefore in shaping reproductive compatibility and, in turn, speciation.


Assuntos
Embrião de Mamíferos/fisiologia , Evolução Molecular , Fucose/metabolismo , Fucosiltransferases/genética , Placenta/fisiologia , Animais , Implantação do Embrião , Embrião de Mamíferos/enzimologia , Embrião de Mamíferos/metabolismo , Feminino , Fucosiltransferases/metabolismo , Glicosilação , Placenta/citologia , Placenta/enzimologia , Placenta/metabolismo , Gravidez
12.
Biol Reprod ; 86(4): 103, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22205696

RESUMO

Normal pregnancy is associated with the presence of circulating placental microvesicles (MVs). Increased MV shedding and altered immune activation are seen in patients with preeclampsia, suggesting that placental MVs may play a role in the pathophysiology of this disease. Therefore, the aim of this study was to investigate the activation of peripheral blood mononuclear cells (PBMCs) by MVs shed by first-trimester, normal term, and preeclamptic term placenta. First-trimester and preeclamptic term, but not normal term, placental-derived MVs activated PBMCs, as evidenced by elevated IL1B. Significant changes were also seen with several other cytokines and chemokines, and in general when compared to normal term MVs, preeclamptic MVs induced a greater pro-inflammatory response in PBMCs. Pretreatment of PBMCs with first-trimester or normal term placental MVs resulted in a dampened IL1B response to a subsequent lipopolysaccharide (LPS) challenge. In contrast, treatment of PBMCs with preeclamptic term placental MVs exacerbated the LPS response. This was also the case for several other cytokines and chemokines. These studies suggest that placental MVs can modulate basal peripheral immune cell activation and responsiveness to LPS during normal pregnancy, and that in preeclampsia this effect is exacerbated.


Assuntos
Citocinas/imunologia , Inflamação/imunologia , Leucócitos Mononucleares/imunologia , Placenta/imunologia , Pré-Eclâmpsia/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Interleucina-1beta/imunologia , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Placenta/metabolismo , Gravidez , Primeiro Trimestre da Gravidez/imunologia
13.
Placenta ; 124: 37-43, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35613499

RESUMO

INTRODUCTION: Little is known about the glycosylation of placental villi and areolae of cetaceans. Term tissue from the delivered placenta of an Indo-Pacific Bottlenose Dolphin (Tursiops aduncus) was examined using lectin histochemistry to compare trophoblast glycosylation in these two locations. METHODS: Placental blocks fixed in 10% formalin were resin-embedded before semithin sections were stained with 24 biotinylated lectins and an avidin-biotin revealing system. RESULTS: Areolar trophoblast was composed of large, bulbous cells packed with numerous granules compared to the smaller, cuboidal cells clothing the chorionic villi, which had a sparser, mainly subapical granule population. Both were richly glycosylated; generally areolar cells were more heavily stained apart from poor binding to some N-acetylgalactosamine and N-acetylglucosamine termini. Most striking was the distribution of α1,2-linked fucosyl residues, weakly expressed in villous trophoblast but intensely stained in some areolar cells, also terminal sialic acids. Some lectins bound in a variable fashion. Staining of terminal α-d-mannose, which locates mainly to lysosomes, was heavy in areolar cells compared to scattered irregular foci in villous cells. DISCUSSION AND CONCLUSION: The many intracellular inclusions reflect ongoing lysosomal breakdown of histotroph in areolar cells which often show heterogeneous glycosylation staining unlike the uniformly stained villous cells, possibly reflecting partial breakdown of ingested sialoglycoprotein, cell turnover or regional variation in uptake of histotroph. Our results indicate that Dolphin areolae are functionally distinct from villous trophoblast, performing absorptive and phagocytic functions similar to other Artiodactyla.


Assuntos
Golfinho Nariz-de-Garrafa , Placenta , Animais , Golfinho Nariz-de-Garrafa/metabolismo , Feminino , Glicosilação , Lectinas/metabolismo , Placenta/metabolismo , Gravidez , Trofoblastos/metabolismo
14.
Placenta ; 125: 29-35, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35058067

RESUMO

Prolonged pregnancy describes a pregnancy that progresses beyond 42 weeks' gestation (294 days). In humans, prolonged pregnancy is associated with increasing perinatal mortality, neonatal compromise and birth by Caesarean section. The underpinning reasons behind these increased risks are unknown; one potential explanation is reduced placental function due to ageing processes. This review describes the structural and functional changes seen in prolonged pregnancy in humans and in animal models. Prolonged pregnancies are associated with reduced placental growth, leading to an increase in fetal to placental weight ratio. Microscopic changes include aggregation of syncytiotrophoblast nuclei, reduced villous vascularity with a concomitant impairment of trophoblast transport processes (reduced pinocytosis); this is associated with increased evidence of oxidative stress, with downstream consequences including cellular senescence, autophagy and apoptosis; importantly many of these changes are similar to fetal growth restriction and pre-eclampsia. Thus, we argue that these observations provide evidence of ageing within the placenta, which may initially be adaptive but can become pathological leading to a reduction in placental function. This provides a biological basis for the increased risk of adverse outcomes observed in prolonged pregnancies. Greater insight into the effects and risks of placental ageing may be useful to guide clinicians on the management of prolonged pregnancies.


Assuntos
Pré-Eclâmpsia , Gravidez Prolongada , Animais , Cesárea/efeitos adversos , Feminino , Retardo do Crescimento Fetal/patologia , Humanos , Placenta/patologia , Pré-Eclâmpsia/patologia , Gravidez , Gravidez Prolongada/patologia
15.
Cells Tissues Organs ; 194(1): 76-84, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21196697

RESUMO

The pericyte is a multifunctional cell closely associated with endothelial cells and may play a role in angiogenesis and vessel stabilisation. Re-examination of over 1,100 micrographs from archival material used to investigate ultrastructural changes in placental development and pathology has identified previously undescribed structures associated with the pericyte of the human placental terminal villus. These structures take the form of outgrowths from the main body of the cell, with a narrow neck rich in cytoplasmic filaments, terminating in swollen tips which appear to bleb off the pericyte and form electron lucent stromal vesicles. Semi-quantitative analysis indicated that these features are present in some placentae from normal, term pregnancies but are increasingly found where capillaries show abnormalities such as a failure to form sinusoids, as in pregnancies complicated by diabetes, postmaturity, rhesus incompatibility and pre-eclampsia. This blebbing is compared with similar phenomena associated with apoptosis and zeiosis and it is suggested that it may contribute to fluid homeostasis where normal mechanisms are impaired by thickening or damage to endothelial cells.


Assuntos
Pericitos/ultraestrutura , Placenta/ultraestrutura , Vilosidades Coriônicas/metabolismo , Vilosidades Coriônicas/ultraestrutura , Feminino , Humanos , Pericitos/metabolismo , Gravidez
16.
Hum Reprod Update ; 27(5): 904-922, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34125187

RESUMO

BACKGROUND: Villous cytotrophoblast (vCTB) is a precursor cell population that supports the development of syncytiotrophoblast (vSTB), the high surface area barrier epithelium of the placental villus, and the primary interface between maternal and fetal tissue. In light of increasing evidence that the placenta can adapt to changing maternal environments or, under stress, can trigger maternal disease, we consider what properties of these cells empower them to exert a controlling influence on pregnancy progression and outcome. OBJECTIVE AND RATIONALE: How are cytotrophoblast proliferation and differentiation regulated in the human placental villus to allow for the increasing demands of the fetal and environmental challenges and stresses that may arise during pregnancy? SEARCH METHODS: PubMed was interrogated using relevant keywords and word roots combining trophoblast, villus/villous, syncytio/syncytium, placenta, stem, transcription factor (and the individual genes), signalling, apoptosis, autophagy (and the respective genes) from 1960 to the present. Since removal of trophoblast from its tissue environment is known to fundamentally change cell growth and differentiation kinetics, research that relied exclusively on cell culture has not been the main focus of this review, though it is mentioned where appropriate. Work on non-human placenta is not systematically covered, though mention is made where relevant hypotheses have emerged. OUTCOMES: The synthesis of data from the literature has led to a new hypothesis for vCTB dynamics. We propose that a reversible transition can occur from a reserve population in G0 to a mitotically active state. Cells from the in-cycle population can then differentiate irreversibly to intermediate cells that leave the cycle and turn on genes that confer the capacity to fuse with the overlying vSTB as well as other functions associated with syncytial barrier and transport function. We speculate that alterations in the rate of entry to the cell cycle, or return of cells in the mitotic fraction to G0, can occur in response to environmental challenge. We also review evidence on the life cycle of trophoblast from the time that fusion occurs, and point to gaps in knowledge of how large quantities of fetal DNA arrive in maternal circulation. We critique historical methodology and make a case for research to re-address questions about trophoblast lifecycle and dynamics in normal pregnancy and the common diseases of pre-eclampsia and fetal growth restriction, where altered trophoblast kinetics have long been postulated. WIDER IMPLICATIONS: The hypothesis requires experimental testing, moving research away from currently accepted methodology towards a new standard that includes representative cell and tissue sampling, assessment of cell cycle and differentiation parameters, and robust classification of cell subpopulations in villous trophoblast, with due attention to gestational age, maternal and fetal phenotype, disease and outcome.


Assuntos
Pré-Eclâmpsia , Trofoblastos , Diferenciação Celular/fisiologia , Feminino , Regulação da Expressão Gênica , Humanos , Placenta , Pré-Eclâmpsia/metabolismo , Gravidez , Trofoblastos/fisiologia
17.
Placenta ; 114: 39-41, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34419717

RESUMO

In view of controversy about the source of placental multinuclear giant cells, we have re-examined the literature which clearly shows they are derived from trophoblastic elements that have populated the decidua. Archival material for electron microscopy from 17 to 18 week placentae demonstrates they can be found connected via desmosomes to the outer extravillous cytotrophoblast cells of anchoring columns, thus identifying a primary source. We suggest their formation is a terminal differentiation step occurring at all stages of invasion from the cell column to the myometrium, progressively reducing the invasive population.


Assuntos
Desmossomos/ultraestrutura , Células Gigantes/citologia , Miométrio/citologia , Placenta/citologia , Trofoblastos/citologia , Feminino , Humanos , Gravidez
18.
Commun Biol ; 4(1): 651, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140633

RESUMO

Assessment 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.


Assuntos
Endométrio/citologia , Menstruação , Organoides/citologia , Adulto , Células Cultivadas , Endométrio/crescimento & desenvolvimento , Endométrio/metabolismo , Feminino , Fertilização in vitro , Humanos , Organoides/crescimento & desenvolvimento , Organoides/metabolismo , Projetos Piloto
19.
Sci Total Environ ; 751: 142235, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33181987

RESUMO

Inhaled particulate matter (PM) from combustion- and friction-sourced air pollution adversely affects organs distant from the lung. A putative mechanism for the remote effect of inhaled PM is that ultrafine, nano-sized fraction (<100 nm) translocates across the air-tissue barrier, directly interacting with phagocytic tissue cells. Although PM is reported in other tissues, whether it is phagocytosed by non-respiratory tissue resident cells is unclear. Using the placenta as an accessible organ for phagocytic cells, we sought to seek evidence for air pollution-derived PM in tissue resident phagocytes. Macrophage-enriched placental cells (MEPCs) were isolated, and examined by light and electron microscopy. MEPC carbon was assessed by image analysis (mean µm2/1000 cells); particle composition and numbers were investigated using magnetic analyses and energy dispersive X-ray spectroscopy. MEPCs phagocytic capacity was assessed by culture with diesel exhaust PM in vitro. Fifteen placentas were analysed. Black inclusions morphologically compatible with inhaled PM were identified within MEPCs from all samples (mean ± SEM carbon loading, 1000 MEPCs/participant of 0.004 ± 0.001 µm2). High resolution scanning/transmission electron microscopy revealed abundant nano-sized particle aggregates within MEPCs. MEPC PM was predominantly carbonaceous but also co-associated with a range of trace metals, indicative of high temperature (i.e. exogenous) generation. MEPCs contained readily-measurable amounts of iron-rich, ferrimagnetic particles, in concentrations/particle number concentrations ranging, respectively, from 8 to 50 ng/g and 10 to 60.107 magnetic particles/g (wet wt) MEPCs. Extracted MEPCs (n = 20/ placenta) were phagocytic for PM since all cells showed increased carbon area after culture with diesel PM in vitro (mean ± SEM increase 7.55 ± 1.26 µm2 carbon PM). These findings demonstrate that inhaled, metal-bearing, air pollution-derived PM can not only translocate to distant organs, but is taken up by tissue resident phagocytes in vivo. The human placenta, and hence probably the fetus, thus appears to be a target for such particles.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Nanopartículas , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Feminino , Humanos , Tamanho da Partícula , Material Particulado/análise , Gravidez , Emissões de Veículos/análise , Emissões de Veículos/toxicidade
20.
J Anat ; 216(1): 144-55, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19900179

RESUMO

In the pregnant mouse endometrium, collagen fibrillogenesis is characterized by the presence of very thick collagen fibrils which are topographically located exclusively within the decidualized stroma. This dynamic biological process is in part regulated by the small leucine-rich proteoglycans decorin and biglycan. In the present study we utilized wild-type (Dcn(+/+)) and decorin-deficient (Dcn(-/-)) time-pregnant mice to investigate the evolution of non-decidualized and decidualized collagen matrix in the uterine wall of these animals. Ultrastructural and morphometric analyses revealed that the organization of collagen fibrils in the pregnant endometrium of both non-decidualized and decidualized stroma showed a great variability of shape and size, regardless of the genotype. However, the decidualized endometrium from Dcn(-/-) mice contained fibrils with larger diameter and more irregular contours as compared to the wild-type littermates. In the Dcn(-/-) animals, the proportion of thin (10-50 nm) fibrils was also higher as compared to Dcn(+/+) animals. On day 7 of pregnancy, biglycan was similarly localized in the decidualized endometrium in both genotypes. Lumican immunostaining was intense both in decidualized and non-decidualized stroma from Dcn(-/-) animals. The present results support previous findings suggesting that decorin participates in uterine collagen fibrillogenesis. In addition, we suggest that the absence of decorin disturbs the process of lateral assembly of thin fibrils, resulting in very thick collagen fibrils with irregular profiles. Our data further suggest that decorin, biglycan and lumican might play an interactive role in collagen fibrillogenesis in the mouse endometrium, a process modulated according to the stage of pregnancy.


Assuntos
Endométrio/ultraestrutura , Proteínas da Matriz Extracelular/deficiência , Colágenos Fibrilares/ultraestrutura , Proteoglicanas/deficiência , Animais , Biglicano , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Proteoglicanas de Sulfatos de Condroitina/fisiologia , Decídua/ultraestrutura , Decorina , Endométrio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/fisiologia , Feminino , Sulfato de Queratano/metabolismo , Sulfato de Queratano/fisiologia , Lumicana , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Gravidez , Proteoglicanas/metabolismo , Proteoglicanas/fisiologia
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