WIDENLIFE - Widening the Scientific Excellence for Studies on Women’s and Fetal Health and Wellbeing
Permanent URI for this collectionhttps://hdl.handle.net/10062/63400
Given that one in six couples face infertility, often caused by female factors, women’s reproductive health is a significant medical and socio-economical challenge. Herein, while addressing this issue, the Estonian research on female reproductive health and medicine has rapidly developed with the lead of University of Tartu (UT). Nevertheless, the UT’s capacity and expertise still falls short of the leading institutions. At the same time, also the most competitive research groups face significant barriers to perform world-class science due to substantial networking gaps that still exist between previously non-linked research teams. TWINNING funding scheme is designed to overcome these aforementioned shortcomings. Thus UT has formed a WIDENLIFE consortium with its world-renowned partners: University of Oxford and Katholieke Universiteit Leuven, and altogether we have set two ambitious objectives to address. Firstly, for the UT: to become one of the leading research and teaching centres for reproductive and fetal medicine in Eastern and Northern Europe. Secondly, for all members of consortia: to intensify trilateral synergies between the research groups in the areas of female reproductive health and medicine. Our specific goals are to highlight the associations between female metabolic health and infertility, provide deeper understating for embryonal development, and offer new tools for infertility treatment and prenatal diagnostics. In order to resolve these objectives, exchange of know-how, ideas and information between the partners will be enhanced, creating the novel clinically valuable information through pooling the expertise and synergy of resources, interests and commitments by universities from Estonia, UK and Belgium. This could also mean a significant contribution to the scientific capacity of the Estonian research community as well as the health technology industry, which is one of the main focus areas for Estonian Smart Specialisation Strategy.
Browse
Browsing WIDENLIFE - Widening the Scientific Excellence for Studies on Women’s and Fetal Health and Wellbeing by Issue Date
Now showing 1 - 20 of 45
- Results Per Page
- Sort Options
Item Stanniocalcin-1 expression in normal human endometrium and dysregulation in endometriosis(2016) Aghajanova, Lusine; Altmäe, Signe; Kasvandik, Sergo; Salumets, Andres; Stavreus-Evers, Anneli; Giudice, Linda C.Objective To determine expression of stanniocalcin-1 (STC1) in human endometrium with and without endometriosis and its regulation by steroid hormones. Design Laboratory study. Setting University. Patient(s) Nineteen women with endometriosis and 33 control women. Intervention(s) Endometrial biopsy and fluid sampling. Main Outcome Measure(s) Analysis of early secretory (ESE) and midsecretory (MSE) endometrial secretomes from fertile women with the use of nano–liquid chromatography–dual mass spectrometry; real-time quantitative polymerase chain reaction, and immunohistochemistry for STC1 and its receptor calcium-sensing receptor (CASR) mRNA and proteins in endometrium with and without endometriosis; evaluation of STC1 and CASR mRNA expression in endometrial stromal fibroblasts (eSF) from women with and without endometriosis decidualized with the use of E2P or 8-bromo-cyclic adenosine monophosphate (cAMP). Result(s) STC1 protein was strongly up-regulated in MSE versus ESE in endometrial fluid of fertile women. STC1 mRNA significantly increased in MSE from women with, but not from those without, endometriosis, compared with proliferative endometrium or ESE, with no significant difference throughout the menstrual cycle between groups. STC1 mRNA in eSF from control women increased >230-fold on decidualization with the use of cAMP versus 45-fold from women with endometriosis, which was not seen on decidualization with E2/P. CASR mRNA did not exhibit significant differences in any condition and was not expressed in isolated eSF. STC1 protein immunoexpression in eSF was significantly lower in women with endometriosis compared with control women. Conclusion(s) STC1 protein is significantly up-regulated in MSE endometrial fluid and is dysregulated in eutopic endometrial tissue from women with endometriosis. It is likely regulated by cAMP and may be involved in the pathogenesis of decidualization defects.Item A novel hypothesis for histone-to-protamine transition in Bos taurus spermatozoa(2016) Sillaste, Gerly; Kaplinski, Lauris; Meier, Riho; Jaakma, Ülle; Eriste, Elo; Salumets, AndresDNA compaction with protamines in sperm is essential for successful fertilization. However, a portion of sperm chromatin remains less tightly packed with histones, which genomic location and function remain unclear. We extracted and sequenced histone-associated DNA from sperm of nine ejaculates from three bulls. We found that the fraction of retained histones varied between samples, but the variance was similar between samples from the same and different individuals. The most conserved regions showed similar abundance across all samples, whereas in other regions, their presence correlated with the size of histone fraction. This may refer to gradual histone–protamine transition, where easily accessible genomic regions, followed by the less accessible regions are first substituted by protamines. Our results confirm those from previous studies that histones remain in repetitive genome elements, such as centromeres, and added new findings of histones in rRNA and SRP RNA gene clusters and indicated histone enrichment in some spermatogenesis-associated genes, but not in genes of early embryonic development. Our functional analysis revealed significant overrepresentation of cGMP-dependent protein kinase G (cGMP-PKG) pathway genes among histone-enriched genes. This pathway is known for its importance in pre-fertilization sperm events. In summary, a novel hypothesis for gradual histone-to-protamine transition in sperm maturation was proposed. We believe that histones may contribute structural information into early embryo by epigenetically modifying centromeric chromatin and other types of repetitive DNA. We also suggest that sperm histones are retained in genes needed for sperm development, maturation and fertilization, as these genes are transcriptionally active shortly prior to histone-to-protamine transition.Item Demographic associations for autoantibodies in disease-free individuals of a European population(2016) Haller-Kikkatalo, Kadri; Alnek, Kristi; Metspalu, Andres; Mihailov, Evelin; Metsküla, Kaja; Kisand, Kalle; Pisarev, Heti; Salumets, Andres; Uibo, RaivoThe presence of autoantibodies usually precedes autoimmune disease, but is sometimes considered an incidental finding with no clinical relevance. The prevalence of immune-mediated diseases was studied in a group of individuals from the Estonian Genome Project (n = 51,862), and 6 clinically significant autoantibodies were detected in a subgroup of 994 (auto)immune-mediated disease-free individuals. The overall prevalence of individuals with immune-mediated diseases in the primary cohort was 30.1%. Similarly, 23.6% of the participants in the disease-free subgroup were seropositive for at least one autoantibody. Several phenotypic parameters were associated with autoantibodies. The results suggest that (i) immune-mediated diseases are diagnosed in nearly one-third of a random European population, (ii) 6 common autoantibodies are detectable in almost one-third of individuals without diagnosed autoimmune diseases, (iii) tissue non-specific autoantibodies, especially at high levels, may reflect preclinical disease in symptom-free individuals, and (iv) the incidental positivity of anti-TPO in men with positive familial anamnesis of maternal autoimmune disease deserves further medical attention. These results encourage physicians to evaluate autoantibodies in addition to treating a variety of patient health complaints to detect autoimmune-mediated disease early.Item Globin mRNA reduction for whole-blood transcriptome sequencing(Scientific Reports, 2016) Krjutškov, Kaarel; Koel, Mariann; Roost, Anne Mari; Katayama, Shintaro; Einarsdottir, Elisabet; Jouhilahti, Eeva-Mari; Söderhäll, Cilla; Jaakma, Ülle; Plaas, Mario; Vesterlund, Liselotte; Lohi, Hannes; Salumets, Andres; Kere, JuhaThe transcriptome analysis of whole-blood RNA by sequencing holds promise for the identification and tracking of biomarkers; however, the high globin mRNA (gmRNA) content of erythrocytes hampers whole-blood and buffy coat analyses. We introduce a novel gmRNA locking assay (GlobinLock, GL) as a robust and simple gmRNA reduction tool to preserve RNA quality, save time and cost. GL consists of a pair of gmRNA-specific oligonucleotides in RNA initial denaturation buffer that is effective immediately after RNA denaturation and adds only ten minutes of incubation to the whole cDNA synthesis procedure when compared to non-blood RNA analysis. We show that GL is fully effective not only for human samples but also for mouse and rat, and so far incompletely studied cow, dog and zebrafish.Item The influence of menstrual cycle and endometriosis on endometrial methylome(Clin Epigenetics, 2016-01) Saare, Merli; Modhukur, Vijayachitra; Suhorutshenko, Marina; Rajashekar, Balaji; Rekker, Kadri; Sõritsa, Deniss; Karro, Helle; Soplepmann, Pille; Sõritsa, Andrei; Lindgren, Cecilia M; Rahmioglu, Nilufer; Drong, Alexander; Becker, Christian M; Zondervan, Krina T; Salumets, Andres; Peters, MaireBACKGROUND: Alterations in endometrial DNA methylation profile have been proposed as one potential mechanism initiating the development of endometriosis. However, the normal endometrial methylome is influenced by the cyclic hormonal changes, and the menstrual cycle phase-dependent epigenetic signature should be considered when studying endometrial disorders. So far, no studies have been performed to evaluate the menstrual cycle influences and endometriosis-specific endometrial methylation pattern at the same time. RESULTS: Infinium HumanMethylation 450K BeadChip arrays were used to explore DNA methylation profiles of endometrial tissues from various menstrual cycle phases from 31 patients with endometriosis and 24 healthy women. The DNA methylation profile of patients and controls was highly similar and only 28 differentially methylated regions (DMRs) between patients and controls were found. However, the overall magnitude of the methylation differences between patients and controls was rather small (Δβ ranging from -0.01 to -0.16 and from 0.01 to 0.08, respectively, for hypo- and hypermethylated CpGs). Unsupervised hierarchical clustering of the methylation data divided endometrial samples based on the menstrual cycle phase rather than diseased/non-diseased status. Further analysis revealed a number of menstrual cycle phase-specific epigenetic changes with largest changes occurring during the late-secretory and menstrual phases when substantial rearrangements of endometrial tissue take place. Comparison of cycle phase- and endometriosis-specific methylation profile changes revealed that 13 out of 28 endometriosis-specific DMRs were present in both datasets. CONCLUSIONS: The results of our study accentuate the importance of considering normal cyclic epigenetic changes in studies investigating endometrium-related disease-specific methylation patterns.Item Imprinted genes and imprinting control regions show predominant intermediate methylation in adult somatic tissues(Epigenomics, 2016-03) Pervjakova, Natalia; Kasela, Silva; Morris, Andrew P; Kals, Mart; Metspalu, Andres; Lindgren, Cecilia M; Salumets, Andres; Mägi, ReedikGenomic imprinting is an epigenetic feature characterized by parent-specific monoallelic gene expression. The aim of this study was to compare the DNA methylation status of imprinted genes and imprinting control regions (ICRs), harboring differentially methylated regions (DMRs) in a comprehensive panel of 18 somatic tissues. The germline DMRs analyzed were divided into ubiquitously imprinted and placenta-specific DMRs, which show identical and different methylation imprints in adult somatic and placental tissues, respectively. We showed that imprinted genes and ICR DMRs maintain methylation patterns characterized by intermediate methylation levels in somatic tissues, which are pronounced in a specific region of the promoter area, located 200–1500 bp from the transcription start site. This intermediate methylation is concordant with gene expression from a single unmethylated allele and silencing of a reciprocal parental allele through DNA methylation. The only exceptions were seen for ICR DMRs of placenta-specific imprinted genes, which showed low levels of methylation, suggesting that these genes escape parent-specific epigenetic regulation in somatic tissues.Item Ovarian Physiology and GWAS: Biobanks, Biology, and Beyond(2016-05) Laisk-Podar, Triin; Lindgren, Cecilia M.; Peters, Maire; Tapanainen, Juha S.; Lambalk, Cornelis B.; Salumets, Andres; Mägi, ReedikOvarian function is central to female fertility, and several genome-wide association studies (GWAS) have been carried out to elucidate the genetic background of traits and disorders that reflect and affect ovarian physiology. While GWAS have been successful in reporting numerous genetic associations and highlighting involved pathways relevant to reproductive aging, for ovarian disorders, such as premature ovarian insufficiency and polycystic ovary syndrome, research has lagged behind due to insufficient study sample size. Novel approaches to study design and analysis methods that help to fit GWAS findings into biological context will improve our knowledge about genetics governing ovarian function in fertility and disease, and provide input for clinical tools and better patient management.Item Copy number variation analysis detects novel candidate genes involved in follicular growth and oocyte maturation in a cohort of premature ovarian failure cases(2016-06) Tšuiko, O.; Nõukas, M.; Žilina, O.; Hensen, K.; Tapanainen, J.; Mägi, R.; Kals, M.; Kivistik, PA.; Haller-Kikkatalo, K.; Salumets, A.; Kurg, A.STUDY QUESTION Can spontaneous premature ovarian failure (POF) patients derived from population-based biobanks reveal the association between copy number variations (CNVs) and POF? SUMMARY ANSWER CNVs can hamper the functional capacity of ovaries by disrupting key genes and pathways essential for proper ovarian function. WHAT IS KNOWN ALREADY POF is defined as the cessation of ovarian function before the age of 40 years. POF is a major reason for female infertility, although its cause remains largely unknown. STUDY DESIGN, SIZE, DURATION The current retrospective CNV study included 301 spontaneous POF patients and 3188 control individuals registered between 2003 and 2014 at Estonian Genome Center at the University of Tartu (EGCUT) biobank. PARTICIPANTS/MATERIALS, SETTING, METHODS DNA samples from 301 spontaneous POF patients were genotyped by Illumina HumanCoreExome (258 samples) and HumanOmniExpress (43 samples) BeadChip arrays. Genotype and phenotype information was drawn from the EGCUT for the 3188 control population samples, previously genotyped with HumanCNV370 and HumanOmniExpress BeadChip arrays. All identified CNVs were subjected to functional enrichment studies for highlighting the POF pathogenesis. Real-time quantitative PCR was used to validate a subset of CNVs. Whole-exome sequencing was performed on six patients carrying hemizygous deletions that encompass genes essential for meiosis or folliculogenesis. MAIN RESULTS AND THE ROLE OF CHANCE Eleven novel microdeletions and microduplications that encompass genes relevant to POF were identified. For example, FMN2 (1q43) and SGOL2 (2q33.1) are essential for meiotic progression, while TBP (6q27), SCARB1 (12q24.31), BNC1 (15q25) and ARFGAP3 (22q13.2) are involved in follicular growth and oocyte maturation. The importance of recently discovered hemizygous microdeletions of meiotic genes SYCE1 (10q26.3) and CPEB1 (15q25.2) in POF patients was also corroborated. LIMITATIONS, REASONS FOR CAUTION This is a descriptive analysis and no functional studies were performed. Anamnestic data obtained from population-based biobank lacked clinical, biological (hormone levels) or ultrasonographical data, and spontaneous POF was predicted retrospectively by excluding known extraovarian causes for premature menopause. WIDER IMPLICATIONS OF THE FINDINGS The present study, with high number of spontaneous POF cases, provides novel data on associations between the genomic aberrations and premature menopause of ovarian cause and demonstrates that population-based biobanks are powerful source of biological samples and clinical data to reveal novel genetic lesions associated with human reproductive health and disease, including POF. STUDY FUNDING/COMPETING INTEREST This study was supported by the Estonian Ministry of Education and Research (IUT20-43, IUT20-60, IUT34-16, SF0180027s10 and 9205), Enterprise Estonia (EU30020 and EU48695), Eureka's EUROSTARS programme (NOTED, EU41564), grants from European Union's FP7 Marie Curie Industry-Academia Partnerships and Pathways (IAPP, SARM, |EU324509) and Horizon 2020 innovation programme (WIDENLIFE, 692065), Academy of Finland and the Sigrid Juselius Foundation.Item Compartmentalized gene expression profiling of receptive endometrium reveals progesterone regulated ENPP3 is differentially expressed and secreted in glycosylated form(2016-09) Boggavarapu, Nageswara Rao; Lalitkumar, Sujata; Joshua, Vijay; Kasvandik, Sergo; Salumets, Andres; Lalit Kumar, Parameswaran Grace; Gemzell-Danielsson, KristinaThe complexity of endometrial receptivity at the molecular level needs to be explored in detail to improve the management of infertility. Here, differential expression of transcriptomes in receptive endometrial glands and stroma revealed Ectonucleotide Pyrophosphatase/Phosphodiesterase 3 (ENPP3) as a progesterone regulated factor and confirmed by various methods, both at mRNA and protein level. The involvement of ENPP3 in embryo attachment was tested in an in vitro model for human embryo implantation. Interestingly, there was high expression of ENPP3 mRNA in stroma but not protein. Presence of N-glycosylated ENPP3 in receptive phase uterine fluid in women confirms its regulation by progesterone and makes it possible to use in a non-invasive test of endometrial receptivity.Item C14orf132 gene is possibly related to extremely low birth weight(2016-09) Tiirats, Airi; Viltrop, Triin; Nõukas, Margit; Reimann, Ene; Salumets, Andres; Kõks, SulevBackground Despite extensive research the genetic component of extremely low birth weight (ELBW) in newborns has remained obscure. Results The aim of the case study was to identify candidate gene(s) causing ELBW in newborns and hypotrophy in infants. A family of four was studied: mother, father and two ELBW-phenotype children. Studies were made of the medical conditions of the second child at birth and post-partum - peculiar phenotype, micro-anomalies, recurrent infections, suspicion of autoimmune hepatitis, multifactorial encephalopathy and suspected metabolic and chromosomal abnormalities. Whole genome single nucleotide polymorphism (SNP) genotyping array was used to investigate the genomic rearrangements in both affected children using peripheral blood DNA samples. Whole blood transcriptome was assessed by using RNA sequencing (RNA-seq) in all four family members. RNA-seq identified a single gene – C14orf132 (chromosome 14 open reading frame 132) differentially expressed, with the level of the transcript significantly lower in the blood samples of the children. Copy number variant (CNV) analysis did not reveal any pathogenic CNVs in the region of C14orf132 gene of both affected children. Conclusion We demonstrated the importance of combining whole genome CNV and transcriptome analysis in identification of the candidate gene(s) in case studies. We propose the C14orf132 gene expression to be associated with the ELBW-phenotype. C14orf132 gene is a novel long non-coding RNA (lincRNA) with unknown function, which might be associated with the pre- and early postnatal developmental delay through the altered gene expression.Item Genome stability of bovine in vivo-conceived cleavage-stage embryos is higher compared to in vitro-produced embryos.(2017) Tšuiko, Olga; Catteeuw, Maaike; Zamani Esteki, Masoud; Destouni, Aspasia; Bogado Pascottini, Osvaldo; Besenfelder, Urban; Havlicek, Vitezslav; Smits, Katrien; Kurg, Ants; Salumets, Andres; D’Hooghe, Thomas; Voet, Thierry; Van Soom, Ann; Vermeesch, Joris RobertSTUDY QUESTION Is the rate and nature of chromosome instability (CIN) similar between bovine in vivo-derived and in vitro-cultured cleavage-stage embryos? SUMMARY ANSWER There is a major difference regarding chromosome stability of in vivo-derived and in vitro-cultured embryos, as CIN is significantly lower in in vivo-derived cleavage-stage embryos compared to in vitro-cultured embryos. WHAT IS KNOWN ALREADY CIN is common during in vitro embryogenesis and is associated with early embryonic loss in humans, but the stability of in vivo-conceived cleavage-stage embryos remains largely unknown. STUDY DESIGN, SIZE, DURATION Because human in vivo preimplantation embryos are not accessible, bovine (Bos taurus) embryos were used to study CIN in vivo. Five young, healthy, cycling Holstein Friesian heifers were used to analyze single blastomeres of in vivo embryos, in vitro embryos produced by ovum pick up with ovarian stimulation (OPU-IVF), and in vitro embryos produced from in vitro matured oocytes retrieved without ovarian stimulation (IVM-IVF). PARTICIPANTS/MATERIALS, SETTING, METHODS Single blastomeres were isolated from embryos, whole-genome amplified and hybridized on Illumina BovineHD BeadChip arrays together with the bulk DNA from the donor cows (mothers) and the bull (father). DNA was also obtained from the parents of the bull and from the parents of the cows (paternal and maternal grandparents, respectively). Subsequently, genome-wide haplotyping and copy-number profiling was applied to investigate the genomic architecture of 171 single bovine blastomeres of 16 in vivo, 13 OPU-IVF and 13 IVM-IVF embryos. MAIN RESULTS AND THE ROLE OF CHANCE The genomic stability of single blastomeres in both of the in vitro-cultured embryo cohorts was severely compromised (P < 0.0001), and the frequency of whole chromosome or segmental aberrations was higher in embryos produced in vitro than in embryos derived in vivo. Only 18.8% of in vivo-derived embryos contained at least one blastomere with chromosomal anomalies, compared to 69.2% of OPU-IVF embryos (P < 0.01) and 84.6% of IVM-IVF embryos (P < 0.001). LARGE SCALE DATA Genotyping data obtained in this study has been submitted to NCBI Gene Expression Omnibus (GEO; accession number GSE95358) LIMITATIONS REASONS FOR CAUTION There were two main limitations of the study. First, animal models may not always reflect the nature of human embryogenesis, although the use of an animal model to investigate CIN was unavoidable in our study. Second, a limited number of embryos were obtained, therefore more studies are warranted to corroborate the findings. WIDER IMPLICATIONS OF THE FINDINGS Although CIN is also present in in vivo-developed embryos, in vitro procedures exacerbate chromosomal abnormalities during early embryo development. Hence, the present study highlights that IVF treatment compromises embryo viability and should be applied with care. Additionally, our results encourage to refine and improve in vitro culture conditions and assisted reproduction technologies. STUDY FUNDING/COMPETING INTEREST(S) The study was funded by the Agency for Innovation by Science and Technology (IWT) (TBM-090878 to J.R.V. and T.V.), the Research Foundation Flanders (FWO; G.A093.11 N to T.V. and J.R.V. and G.0392.14 N to A.V.S. and J.R.V.), the European Union's FP7 Marie Curie Industry-Academia Partnerships and Pathways (IAPP, SARM, EU324509 to J.R.V., T.V., O.T, A.D., A.S. and A.K.) and Horizon 2020 innovation programme (WIDENLIFE, 692065 to J.R.V., O.T., T.V., A.K. and A.S.). M.Z.E., J.R.V. and T.V. are co-inventors on a patent application ZL913096-PCT/EP2014/068315-WO/2015/028576 (‘Haplotyping and copy-number typing using polymorphic variant allelic frequencies’), licensed to Cartagenia (Agilent Technologies)Item Determination of biological activity of gonadotropins hCG and FSH by Förster resonance energy transfer based biosensors(2017) Mazina, Olga; Allikalt, Anni; Tapanainen, Juha S.; Salumets, Andres; Rinken, AgoDetermination of biological activity of gonadotropin hormones is essential in reproductive medicine and pharmaceutical manufacturing of the hormonal preparations. The aim of the study was to adopt a G-protein coupled receptor (GPCR)-mediated signal transduction pathway based assay for quantification of biological activity of gonadotropins. We focussed on studying human chorionic gonadotropin (hCG) and follicle-stimulating hormone (FSH), as these hormones are widely used in clinical practice. Receptor-specific changes in cellular cyclic adenosine monophosphate (cAMP, second messenger in GPCR signalling) were monitored by a Förster resonance energy transfer (FRET) biosensor protein TEpacVV in living cells upon activation of the relevant gonadotropin receptor. The BacMam gene delivery system was used for biosensor protein expression in target cells. In the developed assay only biologically active hormones initiated GPCR-mediated cellular signalling. High assay sensitivities were achieved for detection of hCG (limit of detection, LOD: 5 pM) and FSH (LOD: 100 pM). Even the small-scale conformational changes caused by thermal inactivation and reducing the biological activity of the hormones were registered. In conclusion, the proposed assay is suitable for quantification of biological activity of gonadotropins and is a good alternative to antibody- and animal-testing-based assays used in pharmaceutical industry and clinical research.Item Challenges in endometriosis miRNA studies - From tissue heterogeneity to disease specific miRNAs.(2017) Saare, Merli; Rekker, Kadri; Laisk-Podar, Triin; Rahmioglu, Nilufer; Zondervan, Krina; Salumets, Andres; Götte, Martin; Peters, MaireIn order to uncover miRNA changes in endometriosis pathogenesis, both endometriotic lesions and endometrial biopsies, as well as stromal and epithelial cells isolated from these tissues have been investigated and a large number of dysregulated miRNAs have been reported. However, the concordance between the result of different studies has remained small. One potential explanation for limited overlap between the proposed disease-related miRNAs could be the heterogeneity in tissue composition, as some studies have compared highly heterogeneous whole-lesion biopsies with endometrial tissue, some have compared the endometrium from patients and controls, and some have used pure cell fractions isolated from lesions and endometrium. This review focuses on the results of published miRNA studies in endometriosis to reveal the potential impact of tissue heterogeneity on the discovery of disease-specific miRNA alterations in endometriosis. Additionally, functional studies that explore the roles of endometriosis-involved miRNAs are discussed.Item DNA methylation changes in endometrium and correlation with gene expression during the transition from pre-receptive to receptive phase(2017) Kukushkina, V.; Modhukur, V.; Suhorutšenko, M.; Peters, M.; Mägi, R.; Rahmioglu, N.; Velthut-Meikas, A.; Altmäe, S.; Esteban, FJ.; Vilo, J.; Zondervan, K.; Salumets, A.; Laisk-Podar, T.The inner uterine lining (endometrium) is a unique tissue going through remarkable changes each menstrual cycle. Endometrium has its characteristic DNA methylation profile, although not much is known about the endometrial methylome changes throughout the menstrual cycle. The impact of methylome changes on gene expression and thereby on the function of the tissue, including establishing receptivity to implanting embryo, is also unclear. Therefore, this study used genome-wide technologies to characterize the methylome and the correlation between DNA methylation and gene expression in endometrial biopsies collected from 17 healthy fertile-aged women from pre-receptive and receptive phase within one menstrual cycle. Our study showed that the overall methylome remains relatively stable during this stage of the menstrual cycle, with small-scale changes affecting 5% of the studied CpG sites (22,272 out of studied 437,022 CpGs, FDR < 0.05). Of differentially methylated CpG sites with the largest absolute changes in methylation level, approximately 30% correlated with gene expression measured by RNA sequencing, with negative correlations being more common in 5′ UTR and positive correlations in the gene ‘Body’ region. According to our results, extracellular matrix organization and immune response are the pathways most affected by methylation changes during the transition from pre-receptive to receptive phase.Item Principles guiding embryo selection following genome-wide haplotyping of preimplantation embryos.(2017) Dimitriadou, E.; Melotte, C.; Debrock, S.; Esteki, MZ.; Dierickx, K.; Voet, T.; Devriendt, K.; de Ravel, T.; Legius, E.; Peeraer, K.; Meuleman, C.; Vermeesch, JR.STUDY QUESTION How to select and prioritize embryos during PGD following genome-wide haplotyping? SUMMARY ANSWER In addition to genetic disease-specific information, the embryo selected for transfer is based on ranking criteria including the existence of mitotic and/or meiotic aneuploidies, but not carriership of mutations causing recessive disorders. WHAT IS KNOWN ALREADY Embryo selection for monogenic diseases has been mainly performed using targeted disease-specific assays. Recently, these targeted approaches are being complemented by generic genome-wide genetic analysis methods such as karyomapping or haplarithmisis, which are based on genomic haplotype reconstruction of cell(s) biopsied from embryos. This provides not only information about the inheritance of Mendelian disease alleles but also about numerical and structural chromosome anomalies and haplotypes genome-wide. Reflections on how to use this information in the diagnostic laboratory are lacking. STUDY DESIGN, SIZE, DURATION We present the results of the first 101 PGD cycles (373 embryos) using haplarithmisis, performed in the Centre for Human Genetics, UZ Leuven. The questions raised were addressed by a multidisciplinary team of clinical geneticist, fertility specialists and ethicists. PARTICIPANTS/MATERIALS, SETTING, METHODS Sixty-three couples enrolled in the genome-wide haplotyping-based PGD program. Families presented with either inherited genetic variants causing known disorders and/or chromosomal rearrangements that could lead to unbalanced translocations in the offspring. MAIN RESULTS AND THE ROLE OF CHANCE Embryos were selected based on the absence or presence of the disease allele, a trisomy or other chromosomal abnormality leading to known developmental disorders. In addition, morphologically normal Day 5 embryos were prioritized for transfer based on the presence of other chromosomal imbalances and/or carrier information. LIMITATIONS, REASONS FOR CAUTION Some of the choices made and principles put forward are specific for cleavage-stage-based genetic testing. The proposed guidelines are subject to continuous update based on the accumulating knowledge from the implementation of genome-wide methods for PGD in many different centers world-wide as well as the results of ongoing scientific research. WIDER IMPLICATIONS OF THE FINDINGS Our embryo selection principles have a profound impact on the organization of PGD operations and on the information that is transferred among the genetic unit, the fertility clinic and the patients. These principles are also important for the organization of pre- and post-counseling and influence the interpretation and reporting of preimplantation genotyping results. As novel genome-wide approaches for embryo selection are revolutionizing the field of reproductive genetics, national and international discussions to set general guidelines are warranted. STUDY FUNDING/COMPETING INTEREST(S) The European Union's Research and Innovation funding programs FP7-PEOPLE-2012-IAPP SARM: 324509 and Horizon 2020 WIDENLIFE: 692065 to J.R.V., T.V., E.D. and M.Z.E. J.R.V., T.V. and M.Z.E. have patents ZL910050-PCT/EP2011/060211-WO/2011/157846 (‘Methods for haplotyping single cells’) with royalties paid and ZL913096-PCT/EP2014/068315-WO/2015/028576 (‘Haplotyping and copy-number typing using polymorphic variant allelic frequencies’) with royalties paid, licensed to Cartagenia (Agilent technologies). J.R.V. also has a patent ZL91 2076-PCT/EP20 one 3/070858 (‘High throughout genotyping by sequencing’) with royalties paid.Item The Influence of Different Maternal Microbial Communities on the Development of Infant Gut and Oral Microbiota(2017) Drell, Tiina; Štšepetova, Jelena; Simm, Jaak; Rull, Kristiina; Aleksejeva, Aira; Antson, Anne; Tillmann, Vallo; Metsis, Madis; Sepp, Epp; Salumets, Andres; Mändar, ReetVery few studies have analyzed how the composition of mother’s microbiota affects the development of infant’s gut and oral microbiota during the first months of life. Here, microbiota present in the mothers’ gut, vagina, breast milk, oral cavity, and mammary areola were compared with the gut and oral microbiota of their infants over the first six months following birth. Samples were collected from the aforementioned body sites from seven mothers and nine infants at three different time points over a 6-month period. Each sample was analyzed with 16S rRNA gene sequencing. The gut microbiota of the infants harbored distinct microbial communities that had low similarity with the various maternal microbiota communities. In contrast, the oral microbiota of the infants exhibited high similarity with the microbiota of the mothers’ breast milk, mammary areola and mouth. These results demonstrate that constant contact between microbial communities increases their similarity. A majority of the operational taxonomic units in infant gut and oral microbiota were also shared with the mothers’ gut and oral communities, respectively. The disparity between the similarity and the proportion of the OTUs shared between infants’ and mothers’ gut microbiota might be related to lower diversity and therefore competition in infants’ gut microbiota.Item Variability of genome-wide DNA methylation and mRNA expression profiles in reproductive and endocrine disease related tissues.(2017) Rahmioglu, N.; Drong, AW.; Lockstone, H.; Tapmeier, T.; Hellner, K.; Saare, M.; Laisk-Podar, T.; Dew, C.; Tough, E.; Nicholson, G.; Peters, M.; Morris, AP.; Lindgren, CM.; Becker, CM.; Zondervan, KT.Genome-wide association studies in the fields of reproductive medicine and endocrinology are yielding robust genetic variants associated with disease. Integrated genomic, transcriptomic, and epigenomic molecular profiling studies are common methodologies used to understand the biologic pathways perturbed by these variants. However, molecular profiling resources do not include the tissue most relevant to many female reproductive traits, the endometrium, while the parameters influencing variability of results from its molecular profiling are unclear. We investigated the sources of DNA methylation and RNA expression profile variability in endometrium (n = 135), endometriotic disease tissue (endometriosis), and subcutaneous abdominal fat samples from 24 women, quantifying between-individual, within-tissue (cellular heterogeneity), and technical variation. DNA samples (n = 96) were analyzed using Illumina HumanMethlylation450 BeadChip arrays; RNA samples (n = 39) were analyzed using H12-expression arrays. Variance-component analyses showed that, for the top 10–50% variable DNA methylation/RNA expression sites, between-individual variation far exceeded within-tissue and technical variation. Menstrual-phase accounted for most variability in methylation/expression patterns in endometrium (Pm = 7.8 × 10−3, Pe = 8.4 × 10−5) but not in fat and endometriotic tissue; age was significantly associated with DNA methylation profile of endometrium (Pm = 9 × 10−5) and endometriotic disease tissue (Pm = 2.4 × 10−5); and smoking was significantly associated with DNA methylation in adipose tissue (Pm = 1.8 × 10−3). Hierarchical cluster analysis showed significantly different methylation signatures between endometrium and endometriotic tissue enriched for WNT signaling, angiogenesis, cadherin signaling, and gonadotropin-releasing-hormone-receptor pathways. Differential DNA methylation/expression analyses suggested detection of a limited number of sites with large fold changes (FC > 4), but power calculations accounting for different sources of variability showed that for robust detection >500 tissue samples are required. These results enable appropriate study design for large-scale expression and methylation tissue-based profiling relevant to many reproductive and endocrine traits.Item High-throughput mRNA sequencing of stromal cells from endometriomas and endometrium(2017) Rekker, Kadri; Saare, Merli; Eriste, Elo; Tasa, Tõnis; Kukuškina, Viktorija; Roost, Anne Mari; Anderson, Kristi; Samuel, Kadri; Karro, Helle; Salumets, Andres; Peters, MaireThe aetiology of endometriosis is still unclear and to find mechanisms behind the disease development, it is important to study each cell type from endometrium and ectopic lesions independently. The objective of this study was to uncover complete mRNA profiles in uncultured stromal cells from paired samples of endometriomas and eutopic endometrium. High-throughput mRNA sequencing revealed over 1300 dysregulated genes in stromal cells from ectopic lesions, including several novel genes in the context of endometriosis. Functional annotation analysis of differentially expressed genes highlighted pathways related to cell adhesion, extracellular matrix–receptor interaction and complement and coagulation cascade. Most importantly, we found a simultaneous upregulation of complement system components and inhibitors, indicating major imbalances in complement regulation in ectopic stromal cells. We also performed in vitro experiments to evaluate the effect of endometriosis patients’ peritoneal fluid (PF) on complement system gene expression levels, but no significant impact of PF on C3, CD55 and CFH levels was observed. In conclusion, the use of isolated stromal cells enables to determine gene expression levels without the background interference of other cell types. In the future, a new standard design studying all cell types from endometriotic lesions separately should be applied to reveal novel mechanisms behind endometriosis pathogenesis.Item Ranking and characterization of established BMI and lipid associated loci as candidates for gene-environment interactions(2017) Shungin, Dmitry; Deng, Wei Q.; Varga, Tibor V.; Luan, Jian'an; Mihailov, Evelin; Metspalu, Andres; GIANT Consortium; Morris, Andrew P.; Forouhi, Nita G.; Lindgren, Cecilia; Magnusson, Patrik K. E.; Pedersen, Nancy L.; Hallmans, Göran; Chu, Audrey Y.; Justice, Anne E.; Graff, Mariaelisa; Winkler, Thomas W.; Rose, Lynda M.; Langenberg, Claudia; Cupples, L. Adrienne; Kilpeläinen, Tuomas O.; Scott, Robert A.; Mägi, Reedik; Paré, Guillaume; Franks, Paul W.; Ridker, Paul M.; Wareham, Nicholas J.; Ong, Ken K.; Loos, Ruth J. F.; Chasman, Daniel I.; Ingelsson, ErikPhenotypic variance heterogeneity across genotypes at a single nucleotide polymorphism (SNP) may reflect underlying gene-environment (G×E) or gene-gene interactions. We modeled variance heterogeneity for blood lipids and BMI in up to 44,211 participants and investigated relationships between variance effects (Pv), G×E interaction effects (with smoking and physical activity), and marginal genetic effects (Pm). Correlations between Pv and Pm were stronger for SNPs with established marginal effects (Spearman’s ρ = 0.401 for triglycerides, and ρ = 0.236 for BMI) compared to all SNPs. When Pv and Pm were compared for all pruned SNPs, only BMI was statistically significant (Spearman’s ρ = 0.010). Overall, SNPs with established marginal effects were overrepresented in the nominally significant part of the Pv distribution (Pbinomial <0.05). SNPs from the top 1% of the Pm distribution for BMI had more significant Pv values (PMann–Whitney = 1.46×10−5), and the odds ratio of SNPs with nominally significant (<0.05) Pm and Pv was 1.33 (95% CI: 1.12, 1.57) for BMI. Moreover, BMI SNPs with nominally significant G×E interaction P-values (Pint<0.05) were enriched with nominally significant Pv values (Pbinomial = 8.63×10−9 and 8.52×10−7 for SNP × smoking and SNP × physical activity, respectively). We conclude that some loci with strong marginal effects may be good candidates for G×E, and variance-based prioritization can be used to identify them.Item The management of menopause in women with a history of endometriosis: a systematic review(2017) Gemmell, L.C.; Webster, K.E.; Kirtley, S.; Vincent, K.; Zondervan, K.T.; Becker, C.M.BACKGROUND Endometriosis is typically regarded as a premenopausal disease, resolving after natural or iatrogenic menopause due to declining oestrogen levels. Nonetheless, case reports over the years have highlighted the incidence of recurrent postmenopausal endometriosis. It is now clear that both recurrence and malignant transformation of endometriotic foci can occur in the postmenopausal period. Postmenopausal women are commonly treated with hormone replacement therapy (HRT) to treat climacteric symptoms and prevent bone loss; however, HRT may reactivate endometriosis and stimulate malignant transformation in women with a history of endometriosis. Given the uncertain risks of initiating HRT, it is difficult to determine the best menopausal management for this group of women. OBJECTIVE AND RATIONAL The aim of this study was to systematically review the existing literature on management of menopausal symptoms in women with a history of endometriosis. We also aimed to evaluate the published literature on the risks associated with HRT in these women, and details regarding optimal formulations and timing (i.e. initiation and duration) of HRT. SEARCH METHODS Four electronic databases (MEDLINE via OVID, Embase via OVID, PsycINFO via OVID and CINAHL via EbscoHost) were searched from database inception until June 2016, using a combination of relevant controlled vocabulary terms and free-text terms related to ‘menopause’ and ‘endometriosis’. Inclusion criteria were: menopausal women with a history of endometriosis and menopausal treatment including HRT or other preparations. Case reports/series, observational studies and clinical trials were included. Narrative review articles, organizational guidelines and conference abstracts were excluded, as were studies that did not report on any form of menopausal management. Articles were assessed for risk of bias and quality using GRADE criteria. OUTCOMES We present a synthesis of the existing case reports of endometriosis recurrence or malignant transformation in women undergoing treatment for menopausal symptoms. We highlight common presenting symptoms, potential risk factors and outcomes amongst the studies. Sparse high-quality evidence was identified, with few observational studies and only two randomized controlled trials. Given this paucity of data, no definitive conclusions can be drawn concerning risk. WIDER IMPLICATIONS Due to the lack of high-quality studies, it remains unclear how to advise women with a history of endometriosis regarding the management of menopausal symptoms. The absolute risk of disease recurrence and malignant transformation cannot be quantified, and the impact of HRT use on these outcomes is not known. Multicentre randomized trials or large observational studies are urgently needed to inform clinicians and patients alike.
- «
- 1 (current)
- 2
- 3
- »