RESUMEN
Mouse sperm-associated antigen 6 like (SPAG6L) is an axoneme central apparatus protein, essential for the normal function of the ependymal cell and lung cilia, and sperm flagella. Accumulated evidence has disclosed multiple biological functions of SPAG6L, including ciliary/flagellar biogenesis and polarization, neurogenesis, and neuronal migration. Conventional Spag6l knockout mice died of hydrocephalus, which impedes further investigation of the function of the gene in vivo. To overcome the limitation of the short lifespan of conventional knockout mice, we developed a conditional allele by inserting two loxP sites in the genome flanking exon 3 of the Spag6l gene. By crossing the floxed Spag6l mice to a Hrpt-Cre line which expresses Cre recombinase ubiquitously in vivo, mutant mice that are missing SPAG6L globally were obtained. Homozygous mutant Spag6l mice showed normal appearance within the first week after birth, but reduced body size was observed after 1 week, and all developed hydrocephalus and died within 4 weeks of age. The phenotype mirrored that of the conventional Spag6l knockout mice. The newly established floxed Spag6l model provides a powerful tool to further investigate the role of the Spag6l gene in individual cell types and tissues.
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Hidrocefalia , Animales , Ratones , Hidrocefalia/genética , Integrasas/genética , Ratones NoqueadosRESUMEN
There are few early biomarkers to identify pregnancies at risk of preeclampsia (PE) and abnormal placental function. In this cross-sectional study, we utilized targeted ultra-performance liquid chromatography-ESI MS/MS and a linear regression model to identify specific bioactive lipids that serve as early predictors of PE. Plasma samples were collected from 57 pregnant women prior to 24-weeks of gestation with outcomes of either PE (n = 26) or uncomplicated term pregnancies (n = 31), and the profiles of eicosanoids and sphingolipids were evaluated. Significant differences were revealed in the eicosanoid, (±)11,12 DHET, as well as multiple classes of sphingolipids; ceramides, ceramide-1-phosphate, sphingomyelin, and monohexosylceramides; all of which were associated with the subsequent development of PE regardless of aspirin therapy. Profiles of these bioactive lipids were found to vary based on self-designated race. Additional analyses demonstrated that PE patients can be stratified based on the lipid profile as to PE with a preterm birth linked to significant differences in the levels of 12-HETE, 15-HETE, and resolvin D1. Furthermore, subjects referred to a high-risk OB/GYN clinic had higher levels of 20-HETE, arachidonic acid, and Resolvin D1 versus subjects recruited from a routine, general OB/GYN clinic. Overall, this study shows that quantitative changes in plasma bioactive lipids detected by ultra-performance liquid chromatography-ESI-MS/MS can serve as an early predictor of PE and stratify pregnant people for PE type and risk.
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Preeclampsia , Nacimiento Prematuro , Embarazo , Femenino , Humanos , Recién Nacido , Espectrometría de Masas en Tándem , Placenta , Estudios Transversales , Esfingolípidos , Biomarcadores , Eicosanoides , Aspirina/uso terapéuticoRESUMEN
Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by hyperandrogenemia of ovarian thecal cell origin, resulting in anovulation/oligo-ovulation and infertility. Our previous studies established that ovarian theca cells isolated and propagated from ovaries of normal ovulatory women and women with PCOS have distinctive molecular and cellular signatures that underlie the increased androgen biosynthesis in PCOS. To evaluate differences between gene expression in single-cells from passaged cultures of theca cells from ovaries of normal ovulatory women and women with PCOS, we performed single-cell RNA sequencing (scRNA-seq). Results from these studies revealed differentially expressed pathways and genes involved in the acquisition of cholesterol, the precursor of steroid hormones, and steroidogenesis. Bulk RNA-seq and microarray studies confirmed the theca cell differential gene expression profiles. The expression profiles appear to be directed largely by increased levels or activity of the transcription factors SREBF1, which regulates genes involved in cholesterol acquisition (LDLR, LIPA, NPC1, CYP11A1, FDX1, and FDXR), and GATA6, which regulates expression of genes encoding steroidogenic enzymes (CYP17A1) in concert with other differentially expressed transcription factors (SP1, NR5A2). This study provides insights into the molecular mechanisms underlying the hyperandrogenemia associated with PCOS and highlights potential targets for molecular diagnosis and therapeutic intervention.
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Hiperandrogenismo , Síndrome del Ovario Poliquístico , Femenino , Humanos , Síndrome del Ovario Poliquístico/metabolismo , Análisis de Expresión Génica de una Sola Célula , Hiperandrogenismo/complicaciones , Hiperandrogenismo/genética , Hiperandrogenismo/metabolismo , Factores de Transcripción/genéticaRESUMEN
No data support the suggestion that first-trimester dydrogesterone use increases the risk of fetal abnormalities; however, two low-quality retrospective studies (one retracted by the journal) have suggested such a link. A scoping review and meta-analysis were carried out to address this discrepancy. The literature was reviewed but it was not possible to identify any evidence of a plausible mechanism for potential causality between dydrogesterone and fetal abnormalities. To investigate whether any evidence existed, a preliminary meta-analysis was undertaken of clinical studies published since 2005 on first-trimester dydrogesterone use with assessment of fetal abnormalities. A fixed effects model was used to determine pooled odds ratios with 95% confidence intervals (95% CI). From 83 articles identified, six randomized controlled trials were included. Pooled risk ratios (RR) for maternal dydrogesterone use and fetal abnormalities gave a RR approaching 1 (RR 0.96; 95% CI 0.57, 1.62), confirming previous conclusions of no causal association between fetal abnormalities and first-trimester dydrogesterone use. Physicians, scientists and journal reviewers should exercise due diligence to prevent promulgation of retracted data. We are confident in using dydrogesterone, if indicated, in the treatment of threatened or recurrent miscarriage, and believe that its favourable safety profile should extend to its appropriate use in assisted reproductive technologies.
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Aborto Habitual , Didrogesterona , Aborto Habitual/etiología , Didrogesterona/efectos adversos , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo , Progestinas/uso terapéutico , Estudios RetrospectivosRESUMEN
Neutrophils extensively infiltrate maternal blood vessels in preeclampsia. This could explain why multiple organs are affected in this enigmatic disorder. Lipid peroxides produced by the placenta are probably the first factors that activate neutrophils as they circulate through the intervillous space, but then a second factor specific to pregnancy comes into play, protease-activated receptor 1. The only time neutrophils express protease-activated receptor 1 is during pregnancy. This means that neutrophils can be activated by a mechanism specific to pregnancy, that is, by proteases. Two proteases that are elevated in preeclampsia and activate protease-activated receptor 1 are matrix metalloproteinase-1 and neutrophil elastase. There is an 8-fold increase in vascular protease-activated receptor 1 expression in women with preeclampsia, and protease-activated receptor 1 is also expressed on the placenta, a pregnancy-specific tissue. The question arises if the pregnancy-specific expression of protease-activated receptor 1 is essential to the pathophysiology of preeclampsia. Protease activation of protease-activated receptor 1 in neutrophils of women with normal pregnancies causes activation of RhoA kinase. RhoA kinase phosphorylates nuclear factor-kappa B causing its translocation from the cytosol into the nucleus, increasing the expression of inflammatory genes. This signaling pathway is blocked by inhibition of either protease-activated receptor 1 or RhoA kinase activity. In contrast, neutrophils obtained from preeclamptic women are already activated, with nuclear factor-kappa B localized in the nucleus. Surprisingly, inhibition of either protease-activated receptor 1 or RhoA kinase results in an efflux of nuclear factor-kappa B from the nucleus back into the cytoplasm. Cyclooxygenase-2 seems to be a downstream mediator between protease-activated receptor 1 and RhoA kinase because aspirin inhibits the nuclear translocation of nuclear factor-kappa B and inhibits neutrophil production of superoxide, thromboxane, and tumor necrosis factor alpha. Currently, low-dose aspirin is the standard of care to prevent preeclampsia in high-risk women. Generally, the actions of low-dose aspirin are attributed to selective inhibition of maternal platelet thromboxane production. However, a recent study showed that beneficial effects extend to the placenta, where aspirin corrected the imbalance of increased thromboxane and reduced prostacyclin and oxidative stress. Selective inhibition of placental thromboxane is possible because thromboxane and prostacyclin are compartmentalized. Thromboxane is produced by trophoblast cells and prostacyclin by endothelial cells, so as aspirin crosses the placenta, its levels decline, sparing prostacyclin. Placental oxidative stress is attenuated because cyclooxygenase-2 inhibition decreases the generation of reactive oxygen species to decrease the formation of isoprostanes. The clinical manifestations of preeclampsia can be explained by protease activation of protease-activated receptor 1 in different tissues. In neutrophils, it can account for their activation and inflammatory response. In vascular tissue, protease-activated receptor 1 activation leads to enhanced vascular reactivity to angiotensin II to cause hypertension. In the placenta, it leads to oxidative stress, increased soluble fms-like tyrosine kinase, and thromboxane production. Activation of protease-activated receptor 1 on endothelial cells causes contraction, leading to edema and proteinuria, and activation on platelets leads to coagulation abnormalities. As proteases that activate protease-activated receptor 1 are elevated in the circulation of women with preeclampsia, consideration should be given to the inhibition of protease-activated receptor 1 as a treatment. Recently, The Food and Drug Administration (FDA) approved a protease-activated receptor 1 inhibitor, creating an opportunity to test whether protease-activated receptor 1 inhibition can prevent and/or treat preeclampsia, but a standard dose of aspirin might be just as effective by blocking its downstream actions.
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Preeclampsia/metabolismo , Preeclampsia/prevención & control , Receptor PAR-1/metabolismo , Aspirina/administración & dosificación , Femenino , Fibrinolíticos/administración & dosificación , Humanos , Infiltración Neutrófila/fisiología , Placenta/metabolismo , Preeclampsia/fisiopatología , EmbarazoRESUMEN
Neutrophils expressing cyclooxygenase-2 (COX-2) extensively infiltrate maternal blood vessels in preeclampsia, associated with vascular inflammation. Because pregnancy neutrophils also express protease-activated receptor 1 (PAR-1, F2R thrombin receptor), which they do not in non-pregnant subjects, they can be activated by proteases. We tested the hypothesis that aspirin at a dose sufficient to inhibit COX-2 would reduce inflammatory responses in preeclampsia neutrophils. Neutrophils were isolated from normal pregnant and preeclamptic women at approximately 30 weeks' gestation. Normal pregnancy neutrophils were treated with elastase, a protease elevated in preeclampsia, or elastase plus aspirin to inhibit COX-2, or elastase plus pinane thromboxane, a biologically active structural analog of thromboxane and a thromboxane synthase inhibitor. Preeclamptic pregnancy neutrophils were treated with the same doses of aspirin or pinane thromboxane. Confocal microscopy with immunofluorescence staining was used to determine the cellular localization of the p65 subunit of nuclear factor-kappa B (NF-κB) and media concentrations of thromboxane were measured to evaluate the inflammatory response. In untreated neutrophils of normal pregnant women, p65 was localized to the cytosol. Upon stimulation with elastase, p65 translocated from the cytosol to the nucleus coincident with increased thromboxane production. When neutrophils were co-treated with aspirin or pinane thromboxane, elastase was not able to cause nuclear translocation of p65 or increase thromboxane. In untreated neutrophils of preeclamptic women, the p65 subunit was present in the nucleus and thromboxane production was elevated, but when preeclamptic neutrophils were treated with aspirin or pinane thromboxane, p65 was cleared from the nucleus and returned to the cytosol along with decreased thromboxane production. These findings suggest that COX-2 is a downstream mediator of PAR-1 and demonstrate that PAR-1- mediated inflammation can be inhibited by aspirin. Given the extensive and ubiquitous expression of PAR-1 and COX-2 in preeclamptic women, consideration should be given to treating women with preeclampsia using a dose of aspirin sufficient to inhibit COX-2.
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Aspirina , Preeclampsia , Receptor PAR-1 , Femenino , Humanos , Embarazo/efectos de los fármacos , Aspirina/farmacología , Aspirina/uso terapéutico , Aspirina/metabolismo , Monoterpenos Bicíclicos , Ciclooxigenasa 2/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Péptido Hidrolasas/metabolismo , Preeclampsia/tratamiento farmacológico , Preeclampsia/metabolismo , Receptor PAR-1/efectos de los fármacos , Receptor PAR-1/metabolismo , Tromboxanos/metabolismoRESUMEN
Neutrophils, which extensively infiltrate maternal systemic blood vessels in preeclampsia, express protease-activated receptor 1 (PAR-1) but only during pregnancy. Neutrophils are generally considered to be non-specific in their response, but the pregnancy-specific expression of PAR-1 could result in a gene expression profile unique to pregnancy, which could help explain why the maternal inflammatory response in preeclampsia is systemic rather than localized. We sought to determine if gene expression of pregnancy neutrophils would differ if stimulated by a protease versus bacterial lipopolysaccharide (LPS). We isolated neutrophils from normal pregnant women at 30 weeks' gestation and cultured them with elastase or LPS. We used elastase because it is a protease elevated in women with preeclampsia, and it activates pregnancy neutrophils via PAR-1. RNA was isolated from the neutrophils for sequencing of the transcriptomes. We discovered many differences in the gene expression profiles. For example, exposure to elastase resulted in three times more uniquely expressed genes than LPS, and the number of significantly differentially upregulated and downregulated genes was greater for elastase. Analysis of canonical pathways revealed similarities for innate immunity but also differences. LPS treatment enriched more pathways, but elastase activated more genes in each pathway. Elastase treatment enriched the MAPK signaling pathway, whereas LPS did not. This is significant because MAPK is a key mediator of transcriptional responses. These findings indicate that protease stimulation of pregnancy neutrophils results in a different profile than stimulation with LPS, which may help explain why the sterile inflammatory response of preeclampsia is systemic and unique to pregnancy.
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Lipopolisacáridos , Neutrófilos , Péptido Hidrolasas , Preeclampsia , Femenino , Expresión Génica , Humanos , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Neutrófilos/metabolismo , Elastasa Pancreática/metabolismo , Elastasa Pancreática/farmacología , Péptido Hidrolasas/metabolismo , Péptido Hidrolasas/farmacología , Preeclampsia/metabolismo , Embarazo/metabolismo , Embarazo/fisiología , Receptor PAR-1/metabolismoRESUMEN
Spag6 encodes an axoneme central apparatus protein that is required for normal flagellar and cilia motility. Recent findings suggest that Spag6 plays a role in hearing and planar cell polarity (PCP) in the cochlea of the inner ear. However, a role for Spag6 in the vestibule has not yet been explored. In the present study, the function of Spag6 in the vestibule of the inner ear was examined using Spag6-deficient mice. Our results demonstrate a vestibular disorder in the Spag6 mutants, associated with abnormal ultrastructures of vestibular hair cells and Scarpa's ganglion cells, including swollen stereocilia, decreased crista in mitochondria and swollen Scarpa's ganglion cells. Immunostaining data suggests existence of caspase-dependent apoptosis in vestibular sensory epithelium and Scarpa's ganglion cells. Our observations reveal new functions for Spag6 in vestibular function and apoptosis in the mouse vestibule.
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Apoptosis/genética , Proteínas de Microtúbulos/genética , Mutación , Enfermedades Vestibulares/genética , Animales , Polaridad Celular/genética , Cóclea/citología , Cóclea/fisiología , Femenino , Células Ciliadas Vestibulares/patología , Audición/genética , Masculino , Ratones Transgénicos , Enfermedades Vestibulares/patología , Nervio Vestibular/citología , Nervio Vestibular/patologíaRESUMEN
The road to low-dose aspirin therapy for the prevention of preeclampsia began in the 1980s with the discovery that there was increased thromboxane and decreased prostacyclin production in placentas of preeclamptic women. At the time, low-dose aspirin therapy was being used to prevent recurrent myocardial infarction and other thrombotic events based on its ability to selectively inhibit thromboxane synthesis without affecting prostacyclin synthesis. With the discovery that thromboxane was increased in preeclamptic women, it was reasonable to evaluate whether low-dose aspirin would be effective for preeclampsia prevention. The first clinical trials were very promising, but then two large multi-center trials dampened enthusiasm until meta-analysis studies showed aspirin was effective, but with caveats. Low-dose aspirin was most effective when started <16 weeks of gestation and at doses >100 mg/day. It was effective in reducing preterm preeclampsia, but not term preeclampsia, and patient compliance and patient weight were important variables. Despite the effectiveness of low-dose aspirin therapy in correcting the placental imbalance between thromboxane and prostacyclin and reducing oxidative stress, some aspirin-treated women still develop preeclampsia. Alterations in placental sphingolipids and hydroxyeicosatetraenoic acids not affected by aspirin, but with biologic actions that could cause preeclampsia, may explain treatment failures. Consideration should be given to aspirin's effect on neutrophils and pregnancy-specific expression of protease-activated receptor 1, as well as additional mechanisms of action to prevent preeclampsia.
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Aspirina/administración & dosificación , Placenta/efectos de los fármacos , Placenta/metabolismo , Preeclampsia/metabolismo , Preeclampsia/prevención & control , Animales , Biomarcadores , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Femenino , Expresión Génica , Humanos , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Leucocitos/metabolismo , Leucocitos/patología , Placenta/patología , Preeclampsia/etiología , Embarazo , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Trofoblastos/efectos de los fármacos , Trofoblastos/metabolismoRESUMEN
Neutrophils are activated and extensively infiltrate blood vessels in preeclamptic women. To identify genes that contribute to neutrophil activation and infiltration, we analyzed the transcriptomes of circulating neutrophils from normal pregnant and preeclamptic women. Neutrophils were collected at 30 weeks' gestation and RNA and DNA were isolated for RNA sequencing and 5-hydroxy-methylcytosine (5-hmC) sequencing as an index of dynamic changes in neutrophil DNA methylation. Women with normal pregnancy who went on to develop mild preeclampsia at term had the most uniquely expressed genes (697) with 325 gene ontology pathways upregulated, many related to neutrophil activation and function. Women with severe preeclampsia who delivered prematurely had few pathways up- or downregulated. Cluster analysis revealed that gene expression in women with severe preeclampsia was an inverse mirror image of gene expression in normal pregnancy, while gene expression in women who developed mild preeclampsia was remarkably different from both. DNA methylation marks, key regulators of gene expression, are removed by the action of ten-eleven translocation (TET) enzymes, which oxidize 5-methylcytosines (5mCs), resulting in locus-specific reversal of DNA methylation. DNA sequencing for 5-hmC revealed no differences among the three groups. Genome-wide DNA methylation revealed extremely low levels in circulating neutrophils suggesting they are de-methylated. Collectively, these data demonstrate that neutrophil gene expression profiles can distinguish different preeclampsia phenotypes, and in the case of mild preeclampsia, alterations in gene expression occur well before clinical symptoms emerge. These findings serve as a foundation for further evaluation of neutrophil transcriptomes as biomarkers of preeclampsia phenotypes. Changes in DNA methylation in circulating neutrophils do not appear to mediate differential patterns of gene expression in either mild or severe preeclampsia.
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Proteínas de Unión al ADN/metabolismo , Dioxigenasas/metabolismo , Neutrófilos/metabolismo , Preeclampsia/inmunología , Adulto , Estudios de Casos y Controles , Metilación de ADN , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Activación Neutrófila , Preeclampsia/metabolismo , Embarazo , Tercer Trimestre del Embarazo/metabolismo , Adulto JovenRESUMEN
STUDY QUESTION: Do alterations in pro- and anti-angiogenic estrogen metabolites in follicular fluid (FF) contribute to the follicular growth arrest and anovulation associated with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: FF of PCOS women with anovulation have reduced levels of pro-angiogenic estrogen metabolites (EMs) and vascular endothelial growth factor (VEGF) compared to that of fertile women with regular menstrual cycles, but exogenous gonadotropins increase the pro-angiogenic EMs and VEGF levels in PCOS women. WHAT IS KNOWN ALREADY: PCOS is characterized by the arrest of follicular development that leads to chronic anovulation. Follicular arrest is generally associated with elevated plasma levels of luteinizing hormone (LH), androgens and anti-Mullerian hormone (AMH). There is also reduced angiogenesis in the follicles of PCOS women compared to those of normal cycling women. It is known that angiogenesis is a critical factor during follicular development. We and other investigators have explored the role of EMs in ovarian angiogenesis, particularly in human corpus luteum function, showing that 4-hydroxyestrone (4-OHE1) and 16-ketoestradiol (16-kE2) have pro-angiogenic effects while 2-methoxyestradiol (2-ME2) and 2-methoxyestrone (2-ME1) have anti-angiogenic effects. Additionally, 2-hydroxyestradiol (2-OHE2), which is produced in the ovary, has proliferative and pro-angiogenic properties. We hypothesized that EMs could be involved in angiogenesis necessary for ovarian follicular development in fertile women, and that dysregulation of these factors may contribute to follicular arrest in PCOS. The relationship between EMs, VEGF and AMH in the pathophysiology of follicular arrest in PCOS has not been previously studied at a follicular level in anovulatory women without ovulation induction. STUDY DESIGN, SIZE, DURATION: This is a comparative experimental study of serum and FF collected from different sized follicles (antral Ë10 mm and dominant Ë16 mm) of women with and without ovarian stimulation. The study included women with regular menstrual cycles who were proven to be fertile (n = 20) and PCOS women with follicular arrest who were candidates for ovarian drilling (n = 17), as well as other patients requiring ovarian stimulation, i.e. control women undergoing IVF for male factor infertility (n = 12) and PCOS women undergoing IVF (n = 17). In vitro studies were carried out on granulosa-lutein cells (GCs) obtained from subsets of women undergoing IVF for male factor infertility (n = 6) and PCOS women undergoing IVF (n = 6). GCs were maintained in culture for up to 6 days. PARTICIPANTS/MATERIALS, SETTING, METHODS: Intrafollicular estradiol, estrone and EMs concentrations were determined by high performance liquid chromatography-mass spectrometry. Testosterone in serum was measured by RIA, and LH, FSH and sex hormone-binding globulin in serum were measured with IRMA kits. AMH was determined in serum and FF by enzyme linked immunosorbant assay (ELISA). VEGF levels were measured in FF and conditioned medium by ELISA. Conditioned medium were obtained from cultured GCs. The angiogenic potential was assessed by in vitro angiogenic assays. MAIN RESULTS AND THE ROLE OF CHANCE: Pro-angiogenic EMs (4-OHE1, 16-kE2 and 2-OHE2) and VEGF were lower in FF of antral follicles of PCOS women with follicular arrest compared those of fertile women with ovulatory cycles (P < 0.05). In contrast, higher concentrations of AMH were found in FF of antral follicles from PCOS women with follicular arrest compared to those of fertile women with ovulatory cycles (P < 0.05). Exogenous gonadotropins used in IVF increased pro-angiogenic EMs and VEGF production in PCOS women, reaching similar profiles compared to control women receiving gonadotropins in their IVF treatment for male factor infertility. The pro-angiogenic EM 2-OHE2 increased the angiogenic potential and VEGF levels of GCs from PCOS women compared to the basal condition (P < 0.05). These findings suggest that there is a role for pro-angiogenic EMs in the control of follicular VEGF production. LIMITATIONS, REASONS FOR CAUTION: The limitations include the possibility that in vitro analysis of GCs might not reflect the in vivo mechanisms involved in the pro-angiogenic action of 2-OHE2 since GCs obtained at the time of oocyte retrieval belong to a very early stage of the luteal phase and might not be representative of GCs during follicular growth. Therefore, our findings do not conclusively rule out the possibility that other in vivo mechanisms also account for defective angiogenesis observed in PCOS. WIDER IMPLICATIONS OF THE FINDINGS: The present study highlights the significance of EMs, angiogenic factors and AMH and their interaction in the pathophysiology of follicular development in PCOS. This study provides new insights into the role of pro-angiogenic factors in follicular arrest in PCOS. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by CONICYT/FONDECYT 1140693 and NIH grant R01HD083323. All authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.
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Síndrome del Ovario Poliquístico , Hormona Antimülleriana , Estrógenos , Femenino , Líquido Folicular , Humanos , Masculino , Factor A de Crecimiento Endotelial VascularRESUMEN
'Androgenized' rodent models are widely used to explore the pathophysiology underlying human polycystic ovary syndrome (PCOS), including reproductive and metabolic dysfunction. Based on a recent study using a dihydrotestosterone (DHT)-treated murine model, it has been proposed that prenatal androgen excess alone can predispose to transgenerational transmission of PCOS. From RNA sequencing analysis of metaphase II (MII) oocytes of androgenized lineages, the authors speculated that oocyte factors, including up-regulation of cytotoxic granulosa-associated RNA binding protein-like 1 (TiaL1), are sufficient to promote disease transfer across generations. Although this is an intriguing concept, it was not considered in the context of earlier publications in which the transcriptomes of human MII oocytes from PCOS women undergoing IVF were compared with women without PCOS. In one of these papers, a number of differentially expressed genes in PCOS MII oocytes (TIAL1 was not differentially expressed) were found to have putative response elements in their promoters for androgen receptors and peroxisome proliferating receptor gamma, providing a mechanism for how excess androgens and/or metabolic defects associated with PCOS might affect female germ cells.
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Síndrome del Ovario Poliquístico , Animales , Femenino , Humanos , Ratones , Oocitos , Primates , Proteínas de Unión al ARN , Receptores Androgénicos/genética , TranscriptomaRESUMEN
Sperm differentiation encompasses a complex sequence of morphological changes that takes place in the seminiferous epithelium. In this process, haploid round spermatids undergo substantial structural and functional alterations, resulting in highly polarized sperm. Hallmark changes during the differentiation process include the formation of new organelles, chromatin condensation and nuclear shaping, elimination of residual cytoplasm, and assembly of the sperm flagella. To achieve these transformations, spermatids have unique mechanisms for protein trafficking that operate in a coordinated fashion. Microtubules and filaments of actin are the main tracks used to facilitate the transport mechanisms, assisted by motor and non-motor proteins, for delivery of vesicular and non-vesicular cargos to specific sites. This review integrates recent findings regarding the role of protein trafficking in sperm differentiation. Although a complete characterization of the interactome of proteins involved in these temporal and spatial processes is not yet known, we propose a model based on the current literature as a framework for future investigations.
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Diferenciación Celular , Espermatogénesis/fisiología , Actinas/metabolismo , Animales , Humanos , Masculino , Mamíferos/metabolismo , Mamíferos/fisiología , Microtúbulos/metabolismo , Transporte de Proteínas , EspermatozoidesRESUMEN
The DENND1A locus is associated with polycystic ovary syndrome (PCOS), a disorder characterized by androgen excess. Theca cells from ovaries of PCOS women have elevated levels of a DENND1A splice variant (DENND1A.V2). Forced expression of this variant in normal theca cells increases androgen biosynthesis and CYP17A1 expression, whereas knockdown of the transcript in PCOS theca cells reduced androgen production and CYP17A1 mRNA. We attempted to create a murine model of PCOS by expressing hDENND1A.V2 using standard transgenic approaches. There is no DENND1A.V2 protein equivalent in mice, and the murine Dennd1a gene is essential for viability since Dennd1a knockout mice are embryonically lethal, suggesting that Dennd1a is developmentally critical. Three different hDENND1A.V2 transgenic mice lines were created using CMV, Lhcgr, and TetOn promoters. The hDENND1A.V2 mice expressed hDENND1A.V2 transcripts. While hDENND1A.V2 protein was not detectable by Western blot analyses, appropriate hDENND1A.V2 immunohistochemical staining was observed. Corresponding Cyp17a1 mRNA levels were elevated in ovaries and adrenals of CMV transgenic mice, as were plasma steroid production by theca interstitial cells isolated from transgenic ovaries. Even though the impact of robust hDENND1A.V2 expression could not be characterized, our findings are consistent with the notion that elevated hDENND1A.V2 has a role in the hyperandrogenemia of PCOS.
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Glándulas Suprarrenales/metabolismo , Andrógenos/biosíntesis , Proteínas Adaptadoras de Señalización del Receptor del Dominio de Muerte/metabolismo , Regulación de la Expresión Génica , Factores de Intercambio de Guanina Nucleótido/metabolismo , Ovario/metabolismo , Esteroide 17-alfa-Hidroxilasa/genética , Animales , Biomarcadores , Biopsia , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Femenino , Vectores Genéticos/genética , Humanos , Inmunohistoquímica , Ratones , Síndrome del Ovario Poliquístico/etiología , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patologíaRESUMEN
The placenta is metabolically active and supports the growth of the fetus. We hypothesize that deficits in the capacity of the placenta to maintain bioenergetic and metabolic stability during pregnancy may result in spontaneous preterm birth (SPTB). To explore this hypothesis, we performed a nested cased control study of metabolomic signatures in placentas from women with SPTB (<36 weeks gestation) compared to normal pregnancies (≥38 weeks gestation). To control for the effects of gestational age on placenta metabolism, we also studied a subset of metabolites in non-laboring preterm and term Rhesus monkeys. Comprehensive quantification of metabolites demonstrated a significant elevation in the levels of amino acids, prostaglandins, sphingolipids, lysolipids, and acylcarnitines in SPTB placenta compared to term placenta. Additional quantification of placental acylcarnitines by tandem mass spectrometry confirmed the significant elevation in SPTB human, with no significant differences between midgestation and term placenta in Rhesus macaque. Fatty acid oxidation as measured by the flux of 3H-palmitate in SPTB placenta was lower than term. Collectively, significant and biologically relevant alterations in the placenta metabolome were identified in SPTB placenta. Altered acylcarnitine levels and fatty acid oxidation suggest that disruption in normal substrate metabolism is associated with SPTB.
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Placenta/metabolismo , Nacimiento Prematuro/metabolismo , Adulto , Estudios de Casos y Controles , Femenino , Feto/metabolismo , Edad Gestacional , Humanos , Recién Nacido , Metabolómica/métodos , EmbarazoRESUMEN
Mammalian SPAG6, the orthologue of Chlamydomonas reinhardtii PF16, is a component of the central apparatus of the '9 + 2' axoneme that controls ciliary/flagellar motility, including sperm motility. Recent studies revealed that SPAG6 has functions beyond its role in the central apparatus. Hence, we reexamined the role of SPAG6 in male fertility. In wild-type mice, SPAG6 was present in cytoplasmic vesicles in spermatocytes, the acrosome of round and elongating spermatids and the manchette of elongating spermatids. Spag6-deficient testes showed abnormal spermatogenesis, with abnormalities in male germ cell morphology consistent with the multi-compartment pattern of SPAG6 localization. The armadillo repeat domain of mouse SPAG6 was used as a bait in a yeast two-hybrid screen, and several proteins with diverse functions appeared multiple times, including Snapin, SPINK2 and COPS5. Snapin has a similar localization to SPAG6 in male germ cells, and SPINK2, a key protein in acrosome biogenesis, was dramatically reduced in Spag6-deficient mice which have defective acrosomes. SPAG16L, another SPAG6-binding partner, lost its localization to the manchette in Spag6-deficient mice. Our findings demonstrate that SPAG6 is a multi-functional protein that not only regulates sperm motility, but also plays roles in spermatogenesis in multiple cellular compartments involving multiple protein partners.
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Proteínas de Microtúbulos/metabolismo , Espermatogénesis , Espermatozoides/metabolismo , Acrosoma/metabolismo , Animales , Células CHO , Cricetulus , Infertilidad Masculina/etiología , Infertilidad Masculina/metabolismo , Infertilidad Masculina/patología , Masculino , Ratones Noqueados , Espermatozoides/ultraestructura , Testículo/metabolismo , Proteínas de Transporte Vesicular/metabolismoRESUMEN
BACKGROUND: The human placenta has been traditionally viewed as sterile, and microbial invasion of this organ has been associated with adverse pregnancy outcomes. Yet, recent studies that utilized sequencing techniques reported that the human placenta at term contains a unique microbiota. These conclusions are largely based on the results derived from the sequencing of placental samples. However, such an approach carries the risk of capturing background-contaminating DNA (from DNA extraction kits, polymerase chain reaction reagents, and laboratory environments) when low microbial biomass samples are studied. OBJECTIVE: To determine whether the human placenta delivered at term in patients without labor who undergo cesarean delivery harbors a resident microbiota ("the assemblage of microorganisms present in a defined niche or environment"). STUDY DESIGN: This cross-sectional study included placentas from 29 women who had a cesarean delivery without labor at term. The study also included technical controls to account for potential background-contaminating DNA, inclusive in DNA extraction kits, polymerase chain reaction reagents, and laboratory environments. Bacterial profiles of placental tissues and background technical controls were characterized and compared with the use of bacterial culture, quantitative real-time polymerase chain reaction, 16S ribosomal RNA gene sequencing, and metagenomic surveys. RESULTS: (1) Twenty-eight of 29 placental tissues had a negative culture for microorganisms. The microorganisms retrieved by culture from the remaining sample were likely contaminants because corresponding 16S ribosomal RNA genes were not detected in the same sample. (2) Quantitative real-time polymerase chain reaction did not indicate greater abundances of bacterial 16S ribosomal RNA genes in placental tissues than in technical controls. Therefore, there was no evidence of the presence of microorganisms above background contamination from reagents in the placentas. (3) 16S ribosomal RNA gene sequencing did not reveal consistent differences in the composition or structure of bacterial profiles between placental samples and background technical controls. (4) Most of the bacterial sequences obtained from metagenomic surveys of placental tissues were from cyanobacteria, aquatic bacteria, or plant pathogens, which are microbes unlikely to populate the human placenta. Coprobacillus, which constituted 30.5% of the bacterial sequences obtained through metagenomic sequencing of placental samples, was not identified in any of the 16S ribosomal RNA gene surveys of these samples. These observations cast doubt as to whether this organism is really present in the placenta of patients at term not in labor. CONCLUSION: With the use of multiple modes of microbiologic inquiry, a resident microbiota could not be identified in human placentas delivered at term from women without labor. A consistently significant difference in the abundance and/or presence of a microbiota between placental tissue and background technical controls could not be found. All cultures of placental tissue, except 1, did not yield bacteria. Incorporating technical controls for potential sources of background-contaminating DNA for studies of low microbial biomass samples, such as the placenta, is necessary to derive reliable conclusions.
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Microbiota , Placenta/microbiología , Adulto , Cesárea , Estudios Transversales , Contaminación de ADN , ADN Bacteriano/análisis , Femenino , Marcadores Genéticos , Humanos , Metagenómica , Microbiota/genética , Embarazo , ARN Ribosómico 16S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN , Nacimiento a TérminoRESUMEN
PURPOSE OF REVIEW: The myofibroblast is the culprit in the pathogenesis of fibrosis in systemic sclerosis (SSc). Activation of morphogen signaling pathways has been shown to be critically involved in organ fibrosis. Remarkably, the cellular receptors and key molecules from these signaling pathways are localized in the primary cilium. The primary cilium is a unique cellular organelle present in virtually all cells. This article summarizes recent studies evaluating the association between primary cilia and morphogen signaling driving myofibroblast transition and subsequent fibrosis. RECENT FINDINGS: Emerging observations implicate dysfunctional primary cilia in fibrosis in many different tissues and organs. Primary cilia seem to be necessary for the initiation of the transition and sustained activation of myofibroblasts. We summarize recent progress in this field and propose the primary cilium as a potential mediator of fibrosis pathogenesis in SSc. Understanding the contributions of primary cilia in fibrosis may ultimately inform the development of entirely new approaches for fibrosis prevention and treatment.
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Cilios/patología , Ciliopatías/patología , Fibrosis/metabolismo , Esclerodermia Sistémica/patología , Animales , Humanos , Miofibroblastos/patologíaRESUMEN
A key event in the process of spermiogenesis is the formation of the flagella, which enables sperm to reach eggs for fertilization. Yeast two-hybrid studies revealed that meiosis-expressed gene 1 (MEIG1) and Parkin co-regulated gene (PACRG) interact, and that sperm-associated antigen 16, which encodes an axoneme central apparatus protein, is also a binding partner of MEIG1. In spermatocytes of wild-type mice, MEIG1 is expressed in the whole germ cell bodies, but the protein migrates to the manchette, a unique structure at the base of elongating spermatid that directs formation of the flagella. In the elongating spermatids of wild-type mice, PACRG colocalizes with α-tubulin, a marker for the manchette, whereas this localization was not changed in the few remaining elongating spermatids of Meig1-deficient mice. In addition, MEIG1 no longer localizes to the manchette in the remaining elongating spermatids of Pacrg-deficient mice, indicating that PACRG recruits MEIG1 to the manchette. PACRG is not stable in mammalian cells, but can be stabilized by MEIG1 or by inhibition of proteasome function. SPAG16L is present in the spermatocyte cytoplasm of wild-type mice, and in the manchette of elongating spermatids, but in the Meig1 or Pacrg-deficient mice, SPAG16L no longer localizes to the manchette. By contrast, MEIG1 and PACRG are still present in the manchette of Spag16L-deficient mice, indicating that SPAG16L is a downstream partner of these two proteins. Together, our studies demonstrate that MEIG1/PACRG forms a complex in the manchette and that this complex is necessary to transport cargos, such as SPAG16L, to build the sperm flagella.
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Proteínas de Ciclo Celular/metabolismo , Flagelos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Proteínas/metabolismo , Animales , Anticuerpos Monoclonales , Western Blotting , Células COS , Proteínas de Ciclo Celular/genética , Chlorocebus aethiops , Flagelos/metabolismo , Técnica del Anticuerpo Fluorescente , Ratones , Ratones Mutantes , Proteínas de Microfilamentos , Proteínas Asociadas a Microtúbulos/genética , Chaperonas Moleculares , Proteínas Nucleares/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosfoproteínas/genética , Unión Proteica , Proteínas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espermatogénesis/genética , Espermatogénesis/fisiología , Técnicas del Sistema de Dos HíbridosRESUMEN
Gestational choriocarcinomas are derived from placental trophoblast cells, with HLA-C being the only class I polymorphic molecule expressed. However, choriocarcinomas have not been profiled for endoplasmic reticulum aminopeptidase 2 (ERAP2) expression. ERAP2 trims peptides presented by human leukocyte antigens (HLA) that have shown to modulate immune response. Over 50% of choriocarcinomas we screened lack ERAP2 expression, which suggests that the absence of ERAP2 expression allows immune evasion of choriocarcinoma cells. We demonstrate that the ability of choriocarcinoma cells to activate lymphocytes was lowest with cells lacking ERAP2 (JEG-3) or HLA-C (JAr). This observation suggests that activation is dependent on expression of both ERAP2 and HLA-C molecules. In addition, an ERAP2 variant in which lysine is changed to asparagine (K392N) results in increased trimming activity (165-fold) for hydrophobic peptides and biologically never been detected. We hypothesize that homozygosity for the N392 ERAP2 variant is prohibited because it modulates the immune recognition of placental trophoblasts. We demonstrate that NK-cell activation and killing were significantly dependent on forced expression of the N392 ERAP2 isoform in JEG-3 cells. Cytotoxicity was confirmed by 7AAD killing assays showing that N392 ERAP2-isoform expressing JEG-3 cells had the highest percentage of apoptotic cells independent of the expression level of CD11a on lymphocytes. This is the first report showing that N392 ERAP2 promotes an immune clearance pathway for choriocarcinoma cells, and provides an explanation for why embryonic homozygosity for the N392 ERAP2 variant is not detected in any population.