| 1. |
- Aghajanova, Lusine, et al.
(author)
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Diminished endometrial expression of ghrelin and ghrelin receptor contributes to infertility
- 2010
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In: Reproductive sciences (Thousand Oaks, Calif.). - : Springer Science and Business Media LLC. - 1933-7205 .- 1933-7191. ; 17:9, s. 823-832
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Journal article (peer-reviewed)abstract
- The objectives were to investigate the presence, distribution and sex steroid hormone regulation of ghrelin and its receptor, growth hormone secretagogue receptor (GHSR), in human endometrium in relation to endometrial receptivity and fertility. Endometrial biopsies were obtained from women with unexplained infertility and healthy fertile volunteers. Ishikawa cells were used to mimic the action of ghrelin in endometrium. Immunostaining of GHSR was strong in luminal epithelium and stroma during mid-secretory phase. Ghrelin and GHSR expression is less intense in mid-secretory endometrium of infertile women compared to fertile controls. Treatment with estrogen and/or progesterone or their antagonists did not significantly change the relative expression of GHSR in Ishikawa and stromal cells. Ghrelin was present in and secreted from human blastocysts, which suggest that the communication between human blastocyst and endometrium might involve ghrelin. Low levels of GHSR in endometrium from women with unexplained infertility may in part explain the infertility.
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| 2. |
- Aghajanova, Lusine, et al.
(author)
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Disturbances in the LIF pathway in the endometrium among women with unexplained infertility
- 2009
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In: Fertility and Sterility. - : Elsevier BV. - 0015-0282 .- 1556-5653. ; 91:6, s. 2602-2610
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To study the expression of leukemia inhibitory factor (LIF), its receptors LIFR and gp130, and its inhibitor SOCS1 in endometria from fertile women and infertile women with unexplained infertility. Signaling through the LIF pathway is involved in maintenance of a receptive state of human endometrium. Impaired endometrial receptivity may be a cause of female infertility. DESIGN: Prospective clinical study. SETTING: Hospital-based IVF unit and university-affiliated reproductive research laboratories. PATIENT(S): Twenty-six healthy fertile women and 14 women with unexplained infertility. INTERVENTION(S): Endometrial biopsy. MAIN OUTCOME MEASURE(S): Pinopode formation, expression of LIF, LIFR, gp130, and SOCS1 protein and mRNA in endometrial biopsies. RESULT(S): The expression of LIFR in the endometrium was negatively correlated to the expression of SOCS1 and positively correlated to the formation of pinopodes. In control fertile women, simultaneous intense apical staining of LIFR and gp130 together with faint SOCS1 staining was observed in epithelial cells, whereas the opposite was seen in most women with unexplained infertility. CONCLUSION(S): Unexplained infertility in some women might be explained by disturbances in the LIF pathway in midsecretory-phase endometrium.
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| 3. |
- Aghajanova, Lusine, et al.
(author)
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HB-EGF but not amphiregulin or their receptors HER1 and HER4 is altered in endometrium of women with unexplained infertility
- 2008
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In: Reproductive Sciences. - : Springer Science and Business Media LLC. - 1933-7191 .- 1933-7205. ; 15:5, s. 484-92
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Journal article (peer-reviewed)abstract
- Heparin-binding, epidermal growth factor-like growth factor (HB-EGF) and its receptors (HER I and HER4) play a role in the human implantation process. Amphiregulin is a member of the EGF family but with unknown function in human fertility. It has been suggested that some women with unexplained infertility have defective endometrial development. The aim of this study is to determine the presence of amphiregulin and the receptors HER1 and HER4 in normal human endometrium throughout the menstrual cycle. In addition) the present study aims to compare endometrium from women with unexplained infertility with endometrium from women with male factor infertility and healthy fertile controls. Immunohistochemistry and real-time polymerase chain reaction were used to determine the expression of HB-EGF, HER 1, HER4, and amphiregulin. The stromal staining of HER I and the epithelial staining of HER4 were most intense in the mid- and late-secretory-phase endometrium. Amphiregulin did not vary during the menstrual cycle. In the mid-secretory phase, the protein expression of HB-EGF was lower in endometrium from women with unexplained infertility versus normal endometrium and endometrium from women with malefactor infertility. HB-EGF and HER4 mRNA expression in mid-secretory endometrium of women with unexplained and malefactor infertility were increased compared with normal controls. Impaired endometrial expression of certain members of the EGF family may contribute to infertility in some women with unexplained infertility.
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| 4. |
- Aghajanova, Lusine, et al.
(author)
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No evidence for mutations in NLRP7, NLRP2 or KHDC3L in women with unexplained recurrent pregnancy loss or infertility
- 2015
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In: Human Reproduction. - : Oxford University Press (OUP). - 0268-1161 .- 1460-2350. ; 30:1, s. 232-238
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Journal article (peer-reviewed)abstract
- STUDY QUESTION: Are mutations in NLRP2/7 (NACHT, LRR and PYD domains-containing protein 2/7) or KHDC3L (KH Domain Containing 3 Like) associated with recurrent pregnancy loss (RPL) or infertility?SUMMARY ANSWER: We found no evidence for mutations in NLRP2/7 or KHDC3L in unexplained RPL or infertility.WHAT IS KNOWN ALREADY: Mutations in NLRP7 and KHDC3L are known to cause biparental hydatidiform moles (BiHMs), a rare form of pregnancy loss. NLRP2, while not associated with the BiHM pathology, is known to cause recurrent Beckwith Weidemann Syndrome (BWS).STUDY DESIGN, SIZE, AND DURATION: Ninety-four patients with well characterized, unexplained infertility were recruited over a 9-year period from three IVF clinics in Sweden. Blood samples from 24 patients with 3 or more consecutive miscarriages of unknown etiology were provided by the Recurrent Miscarriage Clinic at St Mary's Hospital, London, UK.PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were recruited into both cohorts following extensive clinical studies. Genomic DNA was isolated from peripheral blood and subject to Sanger sequencing of NLRP2, NLRP7 and KHDC3L. Sequence electropherograms were analyzed by Sequencher v5.0 software and variants compared with those observed in the 1000 Genomes, single nucleotide polymorphism database (dbSNP) and HapMap databases. Functional effects of non-synonymous variants were predicted using Polyphen-2 and sorting intolerant from tolerant (SIFT).MAIN RESULTS AND THE ROLE OF CHANCE: No disease-causing mutations were identified in NLRP2, NLRP7 and KHDC3L in our cohorts of unexplained infertility and RPL.LIMITATIONS, REASONS FOR CAUTION: Due to the limited patient size, it is difficult to conclude if the low frequency single nucleotide polymorphisms observed in the present study are causative of the phenotype. The design of the present study therefore is only capable of detecting highly penetrant mutations.WIDER IMPLICATIONS OF THE FINDINGS: The present study supports the hypothesis that mutations in NLRP7 and KHDC3L are specific for the BiHM phenotype and do not play a role in other adverse reproductive outcomes. Furthermore, to date, mutations in NLRP2 have only been associated with the imprinting disorder BWS in offspring and there is no evidence for a role in molar pregnancies, RPL or unexplained infertility.STUDY FUNDING/COMPETING INTERESTS: This study was funded by the following sources: Estonian Ministry of Education and Research (Grant SF0180044s09), Enterprise Estonia (Grant EU30020); Mentored Resident research project (Department of Obstetrics and Gynecology, Baylor College of Medicine); Imperial NIHR Biomedical Research Centre; Grant Number C06RR029965 from the National Center for Research Resources (NCCR; NIH). No competing interests declared.
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| 5. |
- Altmäe, Signe, et al.
(author)
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Aromatase gene (CYP19A1) variants, female infertility and ovarian stimulation outcome : a preliminary report
- 2009
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In: Reproductive BioMedicine Online. - 1472-6483 .- 1472-6491. ; 18:5, s. 651-657
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Journal article (peer-reviewed)abstract
- Progress has been made towards ascertaining the genetic predictors of ovarian stimulation in IVF. Aromatase cytochrome P450, encoded by the CYP19A1 gene, catalyses a key step in ovarian oestrogen biosynthesis. Hence, the aromatase gene is an attractive candidate for genetic studies. This study aimed to examine the genetic influences of CYP19A1 TCT trinucleotide insertion/deletion (Ins/Del) and (TTTA)(n) microsatellite intronic polymorphisms on ovarian stimulation outcome and aetiology of female infertility. IVF patients (n = 152) underwent ovarian stimulation according to recombinant FSH and gonadotrophin releasing hormone antagonist protocol. Del/Del homozygous patients with shorter TTTA repeats exhibited decreased ovarian FSH sensitivity in ovarian stimulation, which may reflect variations in aromatase gene expression during early antral follicle development. Accordingly, this study demonstrates correlations between Del allele and shorter (TTTA)(n) repeat sizes with smaller ovaries (r = -0.70, P = 0.047) and fewer antral follicles (r = 0.21, P = 0.018) on days 3-5 of spontaneous menstrual cycle, respectively. Furthermore, Del variation linked with low-repeat-number (TTTA)(n) alleles are involved in enhanced genetic susceptibility to unexplained infertility (adjusted OR = 4.33, P = 0.039) and endometriosis (r = -0.88, P = 0.026), which corroborates evidence on the overlapping patient profiles of ovarian dysfunction in both types of female infertility.
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| 6. |
- Altmäe, Signe, et al.
(author)
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Endometrial gene expression analysis at the time of embryo implantation in women with unexplained infertility
- 2010
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In: Molecular human reproduction. - : Oxford University Press (OUP). - 1360-9947 .- 1460-2407. ; 16:3, s. 178-187
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Journal article (peer-reviewed)abstract
- Successful embryo implantation depends on the quality of the embryo, as well as on the receptivity of the endometrium. The aim of this study was to investigate the endometrial gene expression profile in women with unexplained infertility in comparison with fertile controls at the time of embryo implantation in order to find potential predictive markers of uterine receptivity and to identify the molecular mechanisms of infertility. High-density oligonucleotide gene arrays, comprising 44 000 gene targets, were used to define the endometrial gene expression profile in infertile (n = 4) and fertile (n = 5) women during the mid-secretory phase (day LH +7). Microarray results were validated using real-time PCR. Analyses of expression data were carried out using non-parametric methods. Hierarchical clustering and principal component analysis showed a clear distinction in endometrial gene expression between infertile and fertile women. In total we identified 145 significantly (>3-fold change) up-regulated and 115 down-regulated genes in infertile women versus controls. Via Database for Annotation, Visualization and Integrated Discovery functional analysis we detected a substantial number of dysregulated genes in the endometria of infertile women, involved in cellular localization (21.1%) and transport (18.8%) and transporter activity (13.1%) and with major localization in extracellular regions (19.2%). Ingenuity Pathways Analysis of the gene list showed dysregulation of gene pathways involved in leukocyte extravasation signalling, lipid metabolism and detoxification in the endometria of infertile women. In conclusion, endometrial gene expression in women with unexplained infertility at the time of embryo implantation is markedly different from that in fertile women. These results provide new information on genes and pathways that may have functional significance as regards to endometrial receptivity and subsequent embryo implantation.
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| 7. |
- Altmäe, Signe, 1978-, et al.
(author)
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Genetic predictors of controlled ovarian hyperstimulation : where do we stand today?
- 2011
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In: Human Reproduction Update. - : Oxford University Press (OUP). - 1355-4786 .- 1460-2369. ; 17:6, s. 813-828
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Research review (peer-reviewed)abstract
- BACKGROUNDNowadays, the use of IVF has improved the prospects of infertility treatment. The expected outcome of IVF depends greatly on the effectiveness of controlled ovarian hyperstimulation (COH), where exogenous gonadotrophins are used to induce folliculogenesis. The response to stimulation varies substantially among women and is difficult to predict. Several predictive markers of COH outcome have been proposed (e.g. maternal age and ovarian reserve), but the search for optimal predictors is ongoing. Pharmacogenetic studies demonstrate the effects of individual genetic variability on COH outcome and the potential for customizing therapy based on the patient's genome.METHODSMEDLINE, EMBASE, DARE, CINAHL and the Cochrane Library, and references from relevant articles were investigated up to February 2011 regarding any common genetic variation and COH/IVF outcome.RESULTSSeveral polymorphisms in genes involved in FSH signalling, estrogen biosynthesis, folliculogenesis, folate metabolism and other aspects influence the response to exogenous gonadotrophin administration, resulting in differences in COH and IVF outcomes. Nevertheless, the most studied polymorphism FSHR Asn680Ser is practically the only genetic marker, together with ESR1 PvuII T/C, that could be applied in clinical tests.CONCLUSIONSAlthough data are accumulating with evidence suggesting that the ovarian response to COH is mediated by various polymorphisms, the optimal biomarkers and the efficacy of the tests still remain to be evaluated.
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| 8. |
- Altmäe, Signe, et al.
(author)
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Guidelines for the design, analysis and interpretation of 'omics' data : focus on human endometrium
- 2013
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In: Human Reproduction Update. - : Oxford University Press (OUP). - 1355-4786 .- 1460-2369. ; 20:1, s. 12-28
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Research review (peer-reviewed)abstract
- BACKGROUND 'Omics' high-throughput analyses, including genomics, epigenomics, transcriptomics, proteomics and metabolomics, are widely applied in human endometrial studies. Analysis of endometrial transcriptome patterns in physiological and pathophysiological conditions has been to date the most commonly applied 'omics' technique in human endometrium. As the technologies improve, proteomics holds the next big promise for this field. The 'omics' technologies have undoubtedly advanced our knowledge of human endometrium in relation to fertility and different diseases. Nevertheless, the challenges arising from the vast amount of data generated and the broad variation of 'omics' profiling according to different environments and stimuli make it difficult to assess the validity, reproducibility and interpretation of such 'omics' data. With the expansion of 'omics' analyses in the study of the endometrium, there is a growing need to develop guidelines for the design of studies, and the analysis and interpretation of 'omics' data.METHODS Systematic review of the literature in PubMed, and references from relevant articles were investigated up to March 2013.RESULTS The current review aims to provide guidelines for future 'omics' studies on human endometrium, together with a summary of the status and trends, promise and shortcomings in the high-throughput technologies. In addition, the approaches presented here can be adapted to other areas of high-throughput 'omics' studies.CONCLUSION A highly rigorous approach to future studies, based on the guidelines provided here, is a prerequisite for obtaining data on biological systems which can be shared among researchers worldwide and will ultimately be of clinical benefit.
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| 9. |
- Altmäe, Signe
(author)
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Human endometrial receptivity and embryo-endometrium interactions
- 2011
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Doctoral thesis (other academic/artistic)abstract
- Infertility is an increasing medical and social problem affecting more than 10% of couples worldwide. Many underlying causes of human infertility have been overcome by assisted reproductive techniques; nevertheless, the implantation process remains one of the rate-limiting step as regards the success of the treatment. A prerequisite for successful implantation is the adequate preparation of a receptive endometrium and the establishment and maintenance of a viable embryo. The success of implantation further relies upon a two-way dialogue between the embryo and the endometrium. The molecular bases of these preimplantation and implantation processes in humans are not well known. The general aim of the current thesis was to add more understanding into the complex mechanism of human embryo implantation; to identify different factors that play role in endometrial and embryo preparation for successful implantation. In our first approach of identifying factors important for endometrial maturation to a receptive phase, we applied single gene analysis and genome expression analysis to fertile women and women with unexplained infertility. In the endometria of fertile women we identify previously known and new genes and pathways expressed in receptive endometrium, and that several of these genes and pathways were dysregulated in the endometria of women with no explainable reason for their fertility complications. These pathways included LIF pathway and JAK-STAT signalling cascade, coagulation cascade, inflammatory responses, lipid metabolism, and others. We also identified genetic variation in genes involved in blood coagulation to influence gene and protein expression levels in the endometrial cells, and their association with unexplained infertility was demonstrated. Further, we found pinopodes, the endometrial morphological markers, to be abundant in fertile endometria, but scarce in infertile endometria at the time of embryo implantation. Our second study approach was to analyse factors important for implantation-competent blastocyst development. For that we analysed human embryos cultured in vitro. We found a major wave of transcriptional down-regulation in preimplantation embryos, where one possible down-regulation mechanism could operate via microRNA molecules. Finally, we aimed to identify interactions between receptive endometrium and blastocyst-stage embryo. For that we applied a novel network profiling algorithm HyperModules, which combines topological module identification and functional enrichment analysis. The main curated embryo-endometrium interaction network highlighted the importance of cell adhesion molecules in the implantation process. Also cytokine-cytokine receptor interactions were identified, where osteopontin, LIF and LEP pathways were intertwining. We also identified several novel players in human embryo-endometrium interactions at the time of implantation. The current thesis gives new insights into the processes involved in successful implantation in humans. Increasing our knowledge in the processes involved in preimplantation and implantation will facilitate the development of strategies to manipulate endometrial function, embryo development, and embryo-endometrium dialogue in order to promote successful implantation or to inhibit infertility.
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| 10. |
- Altmäe, Signe, 1978-, et al.
(author)
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MicroRNAs miR-30b, miR-30d, and miR-494 Regulate Human Endometrial Receptivity
- 2013
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In: Reproductive Sciences. - : Springer Science and Business Media LLC. - 1933-7191 .- 1933-7205. ; 20:3, s. 308-317
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Journal article (peer-reviewed)abstract
- MicroRNAs (miRNAs) act as important epigenetic posttranscriptional regulators of gene expression. We aimed to gain more understanding of the complex gene expression regulation of endometrial receptivity by analyzing miRNA signatures of fertile human endometria. We set up to analyze miRNA signatures of receptive (LH + 7, n = 4) versus prereceptive (LH + 2, n = 5) endometrium from healthy fertile women. We found hsa-miR-30b and hsa-miR-30d to be significantly upregulated, and hsa-miR-494 and hsa-miR-923 to be downregulated in receptive endometrium. Three algorithms (miRanda, PicTar, and TargetScan) were used for target gene prediction. Functional analyses of the targets using Ingenuity Pathways Analysis and The Database for Annotation, Visualization and Integrated Discovery indicated roles in transcription, cell proliferation and apoptosis, and significant involvement in several relevant pathways, such as axon guidance, Wnt/β-catenin, ERK/MAPK, transforming growth factor β (TGF-β), p53 and leukocyte extravasation. Comparison of predicted miRNA target genes and our previous messenger RNA microarray data resulted in a list of 12 genes, including CAST, CFTR, FGFR2, and LIF that could serve as a panel of genes important for endometrial receptivity. In conclusion, we suggest that a subset of miRNAs and their target genes may play important roles in endometrial receptivity.
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