Proteome Mapping of Cervical Mucus and Its Potential as a Source of Biomarkers in Female Tract Disorders.

Cervical mucus (CM) is a viscous fluid that is produced by the cervical glands and functions as a uterine cervix plug. Its viscosity decreases during ovulation, providing a window for non-invasive sampling. This study focuses on proteomic characterization of CM to evaluate its potential as a non-invasively acquired source of biomarkers and in understanding of molecular (patho)physiology of the female genital tract. The first objective of this work was to optimize experimental workflow for CM processing and the second was to assess differences in the proteomic composition of CM during natural ovulatory cycles obtained from intrauterine insemination (IUI) cycles and in vitro fertilization (IVF) cycles with controlled ovarian hyperstimulation. Proteomic analysis of CM samples revealed 4370 proteins involved in processes including neutrophil degranulation, cellular stress responses, and hemostasis. Differential expression analysis revealed 199 proteins enriched in IUI samples and 422 enriched in IVF. The proteins enriched in IUI were involved in phosphatidic acid synthesis, responses to external stimulus, and neutrophil degranulation, while those enriched in IVF samples were linked to neutrophil degranulation, formation of a cornified envelope and hemostasis. Subsequent analyses clarified the protein composition of the CM and how it is altered by hormonal stimulation of the uterus.

Methods and techniques of fertility preservation in patients with endometriosis.

: Objective: Endometriosis is a chronic disease with a relatively high prevalence in the female population. Both the disease itself and its surgical treatment can adversely affect the fertility of patients. For this reason, endometriosis is offered as a possible indication for fertility preservation by cryopreservation methods. The aim of this paper is to present the current knowledge on the options of fertility preservation in this subpopulation. METHODS: Search of relevant literature in PubMed/Medline, Web of Science and Scopus databases. RESULTS: Fertility preservation by cryopreservation methods has so far been used mainly in the care of women with cancer. With increasing experience, the effectiveness and availability of these methods have increased significantly and the indication spectrum has been extended to selected benign diseases such as endometriosis. Three techniques are currently established in practice: embryo cryopreservation, oocyte cryopreservation and ovarian tissue cryopreservation. Oocyte cryopreservation is the most commonly used technique, since it is the most advantageous for the patient and, according to the available data, is an effective way to increase the chances of future pregnancy for patients with endometriosis The purpose is to realize the protection of reproduction before the planned operation. CONCLUSION: The diagnosis of endometriosis negatively affects the fertility of women. For some patients, the solution is fertility preservation by cryopreservation methods. Further clinical studies are needed to define exact, practically applicable indication criteria, potential risks of procedures and their benefits and cost-effectiveness.

Assisted oocyte activation.

OBJECTIVE: Currently, there is a rapid increase in studies on assisted oocyte activation, which can significantly improve the process of in vitro fertilization. Fertilization of oocytes by conventional methods and by intracytoplasmic sperm injection can be affected by insufficient activation of the oocyte. The reason is mainly deviations in the enzymatic equipment of sperm or oocytes or a non-functional activation cascade. In many cases, fertilization can be achieved using artificial oocyte activation by applying calcium ion donors to the oocytes after sperm microinjection. However, opinions on the safety and reliability of this method are not uniform. The aim of the thesis is to present current knowledge about assisted oocyte activation and its impact not only on in vitro fertilization, but also on subsequent embryonic and fetal development. METHODOLOGY: Research of relevant literature in Web of Science, PubMed/Medline and Scopus databases. RESULTS AND CONCLUSIONS: Based on the literature data and the authors' own experience, it follows that this method is effective and safe from the point of view of further development of the embryo, fetus and postnatal development. Extensive meta-analyses focused on this method were carried out, which did not find a negative impact not only on the embryonic and fetal development of the individual, but this method did not have associated with a negative impact on the psychosomatic development of the children.

The Manufacture of Xeno- and Feeder-Free Clinical-Grade Human Embryonic Stem Cell Lines: First Step for Cell Therapy.

Human embryonic stem cells (hESCs) are increasingly used in clinical trials as they can change the outcome of treatment for many human diseases. They are used as a starting material for further differentiation into specific cell types and to achieve the desirable result of the cell therapy; thus, the quality of hESCs has to be taken into account. Therefore, current good manufacturing practice (cGMP) has to be implemented in the transport of embryos, derivation of inner cell mass to xeno-free, feeder-free and defined hESC culture, and cell freezing. The in-depth characterization of hESC lines focused on safety, pluripotency, differentiation potential and genetic background has to complement this process. In this paper, we show the derivation of three clinical-grade hESC lines, MUCG01, MUCG02, and MUCG03, following these criteria. We developed and validated the system for the manufacture of xeno-free and feeder-free clinical-grade hESC lines that present high-quality starting material suitable for cell therapy according to cGMP.

Assisted reproduction in patients with Klinefelter syndrome.

OBJECTIVE: The goal of this article is to present the current knowledge of Klinefelter syndrome and its impact on male reproductive function as well as the current treatment options. METHODS: PubMed/Medline, WoS and Scopus were searched for articles indexed until November 2021. TEXT: Klinefelter syndrome is a chromosomal aberration with an additional X chromosome in males. This may adversely affect testicular growth and spermatogenesis, thus resulting in male infertility. Recently, new knowledge has appeared about the treatment of male infertility. CONCLUSION: Interdisciplinary approach enables early dia-gnosis and treatment of patients with Klinefelter syndrome. Assisted reproductive technology is essential for infertility treatment in patients with Klinefelter syndrome.

Selected pathological conditions affecting endometrial receptivity.

OBJECTIVE: A summary of new knowledge on embryo implantation in dependence on quality of the endometrium. METHODS: Literature review from August 2022 of the relevant publications in Web of Science, Scopus and PubMed/Medline databases, focused on "endometrial receptivity", "polycystic ovary syndrome", "endometriosis", "SARS-CoV-2". RESULTS: The receptive state of the endometrium is a result of physiological remodeling and immune system activity modulated by the microbio-me. This balance can be disturbed by myomas, polyps, sactosalpings, adenomyosis, endometriosis, polycystic ovary syndrome, infections. The effect of SARS-CoV-2 infection is being discussed. For a successful implantation, timing of transfer is crucial. The ultrasound examination is used conventionally. In specific cases, hysteroscopy and endometrium bio-psy are recommended. Histological and immunohistochemical evaluation is performed together with examination of microbio-me or transcriptome. To support the implantation, gestagenes are used, or metformin in the patients with polycystic ovary syndrome. In cases of a repeated implantation failure, the intrauterine infusion of mononuclear cells or platelet rich plasma is used, subcutaneous application of granulocyte colony stimulating growth factor, intravenous application of atosiban or intrauterine application of human chorionic gonadotropin. CONCLUSION: Recent research in the field of transcriptomics, proteomics and reproductive immunology uncovers the process of implantation more deeply and opens a new stage of the assisted reproduction.

Aspects of embryo selection and their preparation for the formation of human embryonic stem cells intended for human therapy.

OBJECTIVE: The work deals with a clinical part of human embryonic stem cell (hESC) research. The aim of the project is the differentiation of somatic cell types, useful in drug development, regenerative medicine and cell therapy. The aim of this work is to enable targeted therapy of yet incurable diseases. The pluripotent hESCs have unlimited self-renewal capacity. This ability is used in therapy to create missing or damaged cells in the human body. It is of interest to develop clinical-grade hESC lines useful in preclinical and clinical studies. METHODS: The derivation of the hESC must respect the legislation of the Czech Republic and the EU. The aim was to develop an informed consent of both donors for donated discarded embryos that are not suitable for treatment by in vitro fertilization according to Directive 2004/23/EC. The FNBs Center for Assisted Reproduction (CAR) participates in oocyte collection, cultivation and cryopreservation of embryos, communication with clients and ensuring the informed consent of embryo donors. A transport protocol and a methodology for handing over the thawed embryos with the original numerical code were developed. Before the embryos are handed over to the ICRC co-authors workplace (CTEF), they are thawed and, if necessary, recultivated to the blastocyst stage; afterwards, assisted hatching is performed. RESULTS: In the period from January 2018 to July 2020, 138 selected suitable clients were asked for donations, with 52 not responding, 19 terminating and 29 extending the embryo storage. Only 38 clients, i.e. 27.5%, agreed with the usage of their embryos for the preparation of hESCs. In the same period, personal communication with suitable CAR clients took place and another 17 embryo donors were obtained. A total of 160 embryos were obtained from 55 donors aged 26 to 42 years. The embryos were most often frozen in the blastocyst (53 embryos - 33.1%) and morula (74 embryos - 46.3%) stages. Of the 29 genetically examined embryos, only 5 are euploid (17.2%), 2 are mosaic and 22 are aneuploid or with translocations or carriers with a monogenic defect. CONCLUSION: We have an informed consent prepared and approved by the Ethics Committee of the Masaryk University and the University Hospital Brno; 160 donated embryos have been selected and secured. A transport protocol and handover methodology are developed. The plan for the transfer of thawed anonymized embryos in the first phase, October - December 2020, includes approximately 5 thawed blastocysts per week with assisted hatching. After their transfer to the CTEF, the embryoblast will be isolated with subsequent cultivation. The established hESCs must meet the specified criteria of safety, stability and pluripotency. We believe that, in accordance with the project plan, we will obtain at least 3 clinical-grade hESC lines, the first created in the Czech Republic, respecting the requirements for Advanced Medicinal Therapy Products   (AMTP).

Cryopreservation of sperm before gonadotoxic treatment at the University Hospital Brno in the years 1995-2020

OBJECTIVE: Sperm cryopreservation before gonadotoxic treatment is the basic and mos teffective method of preserving reproduction, which can be used during adolescence. The communication summarizes 26 years of experience in the operation of an oncological sperm bank, analyzes spermiograms of oncological patients, assesses the relationship between sperm pathology and diagnosis, and determines the number of deaths and the use of frozen sperm. METHODS: During the existence of CAR 01 (assisted reproduction center), more than 50,000 spermiograms were performed. From January 1995 to December 2020, a total of 24,729 men were examined within the sperm bank, of which 1,448 (5.9%) had an oncological diagnosis. The spermiograms were evaluated according to current WHO (World Health Organization) manuals. Cryopreservation of sperm has undergone a major development. The rules for the storage of frozen cells have been laid down by Act No. 296/2008 Coll. since 2008. In 2019, the methodology "Cryopreservation of reproductive cells and tissues in patients before cancer treatment" was updated. In all cases, the standard thawing technique was used. The sperms were processed by the swim-up method. As part of the treatment with assisted reproduction methods, oocytes were fertilized by the ICSI (intracytoplasmatic sperm injection) micromanipulation technique. RESULTS: Out of 1,448 examined spermiograms in men with oncological diagnoses, testicular cancer was present in 43.7% of patients and malignant diseases of lymphatic and hematopoietic tissue were found in 24.1%, of which 70,1% included Hodgkin's lymphomas and 29,9% were non-Hodgkin's lymphomas. Leukemia was found in 7.9%, bone and cartilage cancers in 6.8%. The age of the clients of the whole group ranged from 13 to 64 years (27.2 ± 6.8 years). A total of 38.3% of men had normozoospermia, 54.2% of spermiograms showed pathological findings in 1 to 3 evaluated parameters and 7.5% of patients had azoospermia. Severe asthenozoospermia (mobility ≤ 10%) was detected in 57.2% of men and severe oligozoospermia (concentration ≤ 1 × 106 mm3) in 22.3% of patients. The lowest values of the spermiogram were found in men with testicular cancer; the best values were seen in CNS (central nervous system) cancers. The cryopreservation of sperm was performed in 1,340 cases (92.5%). So far, a total of 160 men (11.9%) have used frozen sperm, of which 6.2% in our center. In these 83 cases, the ICSI technique was always used, 38 clinical pregnancies (45.8%) and 32 births were achieved. We have registered 424 completed storages of semen (31.6%), of which 148 (11.0% of all oncology patients) were made due to death and the others at patients' request. Using the sperm of the dead is a specific issue. CONCLUSION: In cancer patients, sperm pathologies occur in high percentage. The lowest spermiogram values were found in men with testicular cancer. It is necessary to take into account long-term storage and fertilization by micromanipulation methods. The number of men who die is significantly higher than the number of those who use sperm to treat infertility. Cryopreservation of sperm should be offered to each patient prior to the therapy leading to the destruction of spermatogenesis.

Adenomyosis - its possible effect on endometrial function and receptivity

OBJECTIVE: There have been many studies on adenomyosis, which can impair the quality of life of a woman. There are various kinds of opinions on the pathogenesis, diagnostics and treatment of adenomyosis. The goal of this article is to present the current knowledge of adenomyosis and its impact on the endometrial function and receptivity. METHODS: PubMed/Medline, Web of Sciences and Scopus were searched for the articles in English indexed until February 2021 with terms of: adenomyosis, endometrial receptivity, and infertility. RESULTS: Recent studies on angiogenesis and epithelial-mesenchymal transition in the endometrium bring new information on the ethiology and pathogenesis of adenomyosis. In clinical practice, the main diagnostic methods of adenomyosis include transvaginal ultrasound, magnetic resonance imaging or hysteroscopy, although the definitive confirmation is set by histopathological examination. The rules of #Enzian classification of endometriosis should be applied for the classification of adenomyosis. The treatment of adenomyosis should consider individual clinical presentation and reproductive plans of a patient and should be performed in centers for the treatment of endometriosis. CONCLUSION: Adenomyosis affects endometrial vascularisation and epithelial-mesenchymal transition/mesenchymal-epithelial transition; thus, it can be the cause of irregular uterine bleeding or embryo implantation failure. The research and analysis of endometrial proteome could lead to the new ways of adenomyosis treatment.

Solved problems of reproductive medicine in the Czech Republic 2020.

INTRODUCTION: During the 30th symposium of assisted reproduction held on November 11, 2020 in Brno, the solved problems in reproductive medicine in the Czech Republic in 2020 were presented. The selected topics have concerned not only current issues in the field of clinical embryology and genetics as well as gynecology, but also legislation and ethics. Discussed topics: 1. How much time does the doctor have in the CAR (centrum of assisted reproduction) outpatient clinic per patient and how does the embryologist communicate with clients? 2. Reproduction and PGT-M in oncology patients and patients at risk with hereditary oncogenic mutations. 3. Non-invasive genetic testing of embryos from culture medium. 4. Genome editing. 5. What is the need to monitor hormonal levels in stimulation protocols? 6. Monitoring and embryo selection for transfer/kryo. 7. Is it time to change the law on donor remuneration? METHODS: The topics were prepared in advance by authorized members of our company with the task of elaborating theses, which they presented in a separate conference block. The presentation and the discussion were broadcast directly from the broadcast studio at Hotel International via an online connection. After the conference, all discussion topics and comments were incorporated. CONCLUSION: The work presents the state of the solved problems of reproductive medicine in the Czech Republic.

Genes regulating hormone stimulus and response to protein signaling revealed differential expression pattern during porcine oocyte in vitro maturation, confirmed by lipid concentration.

Genes influencing oocyte maturation may be valuable for predicting their developmental potential, as well as discerning the mechanistic pathways regulating oocyte development. In the presented research microarray gene expression analysis of immature and in vitro matured porcine oocytes was performed. Two groups of oocytes were compared in the study: before (3 × n = 50) and after in vitro maturation (3 × n = 50). The selection of viable oocytes was performed using the brilliant cresyl blue (BCB) test. Furthermore, microarrays and RT-qPCR was used to analyze the transcriptome of the oocytes before and after IVM. The study focused on the genes undergoing differential expression in two gene-ontology groups: "Cellular response to hormone stimulus" and "Cellular response to unfolded protein", which contain genes that may directly or indirectly be involved in signal transduction during oocyte maturation. Examination of all the genes of interest showed a lower level of their expression after IVM. From the total number of genes in these gene ontologies ten of the highest change in expression were identified: FOS, ID2, BTG2, CYR61, ESR1, AR, TACR3, CCND2, EGR2 and TGFBR3. The successful maturation of the oocytes was additionally confirmed with the use of lipid droplet assay. The genes were briefly described and related to the literature sources, to investigate their potential roles in the process of oocyte maturation. The results of the study may serve as a basic molecular reference for further research aimed at improving the methods of oocyte in vitro maturation, which plays an important role in the procedures of assisted reproduction.

Transcriptomic analysis of expression of genes regulating cell cycle progression in porcine ovarian granulosa cells during short-term in vitro primary culture.

The primary function of ovarian granulosa cells (GCs) is the support of oocytes during maturation and development. Molecular analyses of granulosa cell-associated processes, leading to improvement of understanding of the cell cycle events during the formation of ovarian follicles (folliculogenesis), may be key to improve the in vitro fertilization procedures. Primary in vitro culture of porcine GCs was employed to examine the changes in the transcriptomic profile of genes belonging to "cell cycle", "cell division", "cell cycle process", "cell cycle phase transition", "cell cycle G1/S phase transition", "cell cycle G2/M phase transition" and "cell cycle checkpoint" ontology groups. During the analysis, microarrays were employed to study the transcriptome of GCs, analyzing the total RNA of cells from specific periods of in vitro cultures. This research was based on material obtained from 40 landrace gilts of similar weight, age and the same living conditions. RNA was isolated at specific timeframes: before the culture was established (0 h) and after 48 h, 96 h and 144 h in vitro. Out of 133 differentially expressed genes, we chose the 10 most up-regulated (SFRP2, PDPN, PDE3A, FGFR2, PLK2, THBS1, ETS1, LIF, ANXA1, TGFB1) and the 10 most downregulated (IGF1, NCAPD2, CABLES1, H1FOO, NEK2, PPAT, TXNIP, NUP210, RGS2 and CCNE2). Some of these genes known to play key roles in the regulation of correct cell cycle passage (up-regulated SFRP2, PDE3A, PLK2, LIF and down-regulated CCNE2, TXNIP, NEK2). The data obtained provide a potential reference for studies on the process of mammalian folliculogenesis, as well as suggests possible new genetic markers for cell cycle progress in in vitro cultured porcine granulosa cells.

Genes responsible for proliferation, differentiation, and junction adhesion are significantly up-regulated in human ovarian granulosa cells during a long-term primary in vitro culture.

The human ovarian granulosa cells (GCs) surround the oocyte and form the proper architecture of the ovarian follicle. The ability of GCs to proliferate and differentiate in the conditions of in vitro culture has been proven. However, there is still a large field for extensive investigation of molecular basics, as well as marker genes, responsible for these processes. This study aimed to find the new marker genes, encoding proteins that regulate human GCs in vitro capability for proliferation and differentiation during long-term primary culture. The human follicular GCs were collected from hyper-stimulated ovarian follicles during IVF procedures and transferred to a long-term in vitro culture. The culture lasted for 30 days, with RNA samples isolated at days 1, 7, 15, 30. Transcriptomic analysis was then performed with the use of Affymetrix microarray. Obtained results were then subjected to bioinformatical evaluation and sorting. After subjecting the datasets to KEGG analysis, three differentially expressed ontology groups "cell differentiation" (GO:0030154), "cell proliferation" (GO:0008283) and "cell-cell junction organization" (GO:0045216) were chosen for further investigation. All three of those ontology groups are involved in human GCs' in vitro lifespan, proliferation potential, and survival capability. Changes in expression of genes of interest belonging to the chosen GOs were validated with the use of RT-qPCR. In this manuscript, we suggest that VCL, PARVA, FZD2, NCS1, and COL5A1 may be recognized as new markers of GC in vitro differentiation, while KAT2B may be a new marker of their proliferation. Additionally, SKI, GLI2, FERMT2, and CDH2 could also be involved in GC in vitro proliferation and differentiation processes. We demonstrated that, in long-term in vitro culture, GCs exhibit markers that suggest their ability to differentiate into different cells types. Therefore, the higher expression profile of these genes may also be associated with the induction of cellular differentiation processes that take place beyond the long-term primary in vitro culture.

"Biological Adhesion" is a Significantly Regulated Molecular Process during Long-Term Primary In Vitro Culture of Oviductal Epithelial Cells (Oecs): A Transcriptomic and Proteomic Study.

Oviductal epithelial cells (OECs) actively produce stimulating and protecting factors, favoring survival and viability of gametes and early embryos. The oviduct participates in the initial reproductive events, which strongly depends on adhesion. The analysis of differential gene expression in OECs, during long-term in vitro culture, enables recognition of new molecular markers regulating several processes, including "biological adhesion". Porcine oviducts were stained with hematoxylin and eosin, as well as with antibodies against epithelial markers. Then, OECs were long-term in vitro cultured and after 24 h, 7, 15, and 30 days of culture were subjected to transcriptomic and proteomic assays. Microarrays were employed to evaluate gene expression, with Matrix-assisted laser desorption/ionization-time of light (MALDI-TOF) mass spectrometry applied to determine the proteome. The results revealed proper morphology of the oviducts and typical epithelial structure of OECs during the culture. From the set of differentially expressed genes (DEGs), we have selected the 130 that encoded proteins detected by MALDI-TOF MS analysis. From this gene pool, 18 significantly enriched gene ontology biological processes (GO BP) terms were extracted. Among them we focused on genes belonging to "biological adhesion" GO BP. It is suggested that increased expression of studied genes can be attributed to the process of intensive secretion of substances that exhibit favorable influence on oviductal environment, which prime gametes adhesion and viability, fertilization, and early embryo journey.

Transcriptomic Pattern of Genes Regulating Protein Response and Status of Mitochondrial Activity Are Related to Oocyte Maturational Competence-A Transcriptomic Study.

This paper aims to identify and describe new genetic markers involved in the processes of protein expression and modification reflected in the change of mitochondrial activity before and after in vitro maturation of the oocyte. Porcine oocytes collected from the ovaries of slaughtered landrace gilts were subjected to the process of in vitro maturation. Transcriptomic changes in the expression profile of oocyte genes involved in response to hypoxia, the transmembrane protein receptor serine threonine kinase signaling pathway, the "transforming growth factor ß receptor signaling pathway", "response to protein stimulus", and "response to organic substance" were investigated using microarrays. The expression values of these genes in oocytes was analyzed before (immature) and after (mature) in vitro maturation, with significant differences found. All the significantly altered genes showed downregulation after the maturation process. The most changed genes from these gene ontologies, FOS, ID2, VEGFA, BTG2, CYR61, ESR1, AR, TACR3, CCND2, CHRDL1, were chosen to be further validated, described and related to the literature. Additionally, the mitochondrial activity of the analyzed oocytes was measured using specific dyes. We found that the mitochondrial activity was higher before the maturation process. The analysis of these results and the available literature provides a novel insight on the processes that occur during in vitro oocyte maturation. While this knowledge may prove to be useful in further research of the procedures commonly associated with in vitro fertilization procedures, it serves mostly as a basic reference for further proteomic, in vivo, and clinical studies that are necessary to translate it into practical applications.

Study of metabolic activity of human embryos focused on amino acids by capillary electrophoresis with light-emitting diode-induced fluorescence detection.

Assisted reproduction is a quickly developing field of reproductive medicine whose importance is growing every year due to the increasing number of patients suffering from infertility. As a result, there is a need for the continuous development and/or improvement of assisted reproductive technologies. This paper presents a new method for the in vitro measurement of the amino acid turnover of developing embryos based on capillary electrophoresis with light-emitting diode-induced fluorescence detection. Amino acids were derivatized with naphthalene-2,3-dicarboxaldehyde/NaCN, and the resulting fluorescent derivatives were baseline resolved within 25 min in a background electrolyte comprised of 50 mM sodium tetraborate, 73 mM sodium dodecyl sulphate, 5 mM sodium deoxycholate and 2.5 mM (2-hydroxypropyl)-ß-cyclodextrin (pH ≈ 9.3). The migration time and the peak area repeatability (n = 10) were below 0.5 and 4.3%, respectively. The limits of detection ranged from 12.6 nM (histidine) to 39.3 nM (taurine). The developed method, which only requires 2 µL of raw sample, was successfully applied for determining the metabolic activity of human embryos exposed to different environmental stress conditions.

The Unique Mechanisms of Cellular Proliferation, Migration and Apoptosis are Regulated through Oocyte Maturational Development-A Complete Transcriptomic and Histochemical Study.

The growth and development of oocyte affect the functional activities of the surrounding somatic cells. These cells are regulated by various types of hormones, proteins, metabolites, and regulatory molecules through gap communication, ultimately leading to the development and maturation of oocytes. The close association between somatic cells and oocytes, which together form the cumulus-oocyte complexes (COCs), and their bi-directional communication are crucial for the acquisition of developmental competences by the oocyte. In this study, oocytes were extracted from the ovaries obtained from crossbred landrace gilts and subjected to in vitro maturation. RNA isolated from those oocytes was used for the subsequent microarray analysis. The data obtained shows, for the first time, variable levels of gene expression (fold changes higher than |2| and adjusted p-value < 0.05) belonging to four ontological groups: regulation of cell proliferation (GO:0042127), regulation of cell migration (GO:0030334), and regulation of programmed cell death (GO:0043067) that can be used together as proliferation, migration or apoptosis markers. We have identified several genes of porcine oocytes (ID2, VEGFA, BTG2, ESR1, CCND2, EDNRA, ANGPTL4, TGFBR3, GJA1, LAMA2, KIT, TPM1, VCP, GRID2, MEF2C, RPS3A, PLD1, BTG3, CD47, MITF), whose expression after in vitro maturation (IVM) is downregulated with different degrees. Our results may be helpful in further elucidating the molecular basis and functional significance of a number of gene markers associated with the processes of migration, proliferation and angiogenesis occurring in COCs.

Genes of cellular components of morphogenesis in porcine oocytes before and after IVM.

Proper oocyte maturation in mammals produces an oocyte capable of monospermic fertilization and embryo preimplantation. The cumulus-oocyte complexes (COCs), surrounding an oocyte, play a significant role in oocyte maturation. During this process, when the COCs undergo cumulus expansion wherein tightly compact cumulus cells (CCs) form a dispersed structure, permanent biochemical and molecular modifications occur in the maturing oocytes, indicating that the gene expression between immature and mature oocytes differs significantly. This study focuses on the genes responsible for the cellular components of morphogenesis within the developing oocyte. Brilliant cresyl blue (BCB) was used to determine the developmental capability of porcine oocytes. The immature oocytes (GV stage) were compared with matured oocytes (MII stage), using microarray and qRT-PCR analysis to track changes in the genetic expression profile of transcriptome genes. The data showed substantial upregulation of genes influencing oocyte's morphology, cellular migration and adhesion, intracellular communication, as well as plasticity of nervous system. Conversely, downregulation involved genes related to microtubule reorganization, regulation of adhesion, proliferation, migration and cell differentiation processes in oocytes. This suggests that most genes recruited in morphogenesis in porcine oocyte in vitro, may have cellular maturational capability, since they have a higher level of expression before the oocyte's matured form. It shows the process of oocyte maturation and developmental capacity is orchestrated by significant cellular modifications during morphogenesis.

Expression of genes associated with BMP signaling pathway in porcine oocytes before and after IVM - a microarray approach.

BACKGROUND: The full maturational capability of mammalian oocytes is accompanied by nuclear and cytoplasmic modifications, which are associated with proliferation and differentiation of surrounding cumulus cells. These events are regulated on molecular level by the expression of target genes involved in signal transduction pathways crucial for folliculogenesis and oogenesis. Transforming growth factor beta signaling includes several molecules that are involved in the regulation of oogenesis and embryo growth, including bone morphogenetic protein (BMP). However, the BMP-related gene expression profile in oocytes at different maturational stages requires further investigation. METHODS: Oocytes were isolated from pubertal crossbred Landrace gilts follicles, selected with a use of BCB staining test and analyzed before and after in vitro maturation. Gene expression profiles were examined using an Affymetrix microarray approach and validated by RT-qPCR. Database for Annotation, Visualization, and Integrated Discovery (DAVID) software was used for the extraction of the genes belonging to a BMP-signaling pathway ontology group. RESULTS: The assay revealed 12,258 different transcripts in porcine oocytes, among which 379 genes were down-regulated and 40 were up-regulated. The DAVID database indicated a "BMP signaling pathway" ontology group, which was significantly regulated in both groups of oocytes. We discovered five up-regulated genes in oocytes before versus after in vitro maturation (IVM): chordin-like 1 (CHRDL1), follistatin (FST), transforming growth factor-beta receptor-type III (TGFßR3), decapentaplegic homolog 4 (SMAD4), and inhibitor of DNA binding 1 (ID1). CONCLUSIONS: Increased expression of CHRDL1, FST, TGFßR3, SMAD4, and ID1 transcripts before IVM suggested a subordinate role of the BMP signaling pathway in porcine oocyte maturational competence. Conversely, it is postulated that these genes are involved in early stages of folliculogenesis and oogenesis regulation in pigs, since in oocytes before IVM increased expression was observed.

Significant Down-Regulation of "Biological Adhesion" Genes in Porcine Oocytes after IVM.

Proper maturation of the mammalian oocyte is a compound processes determining successful monospermic fertilization, however the number of fully mature porcine oocytes is still unsatisfactory. Since oocytes' maturation and fertilization involve cellular adhesion and membranous contact, the aim was to investigate cell adhesion ontology group in porcine oocytes. The oocytes were collected from ovaries of 45 pubertal crossbred Landrace gilts and subjected to two BCB tests. After the first test, only granulosa cell-free BCB⁺ oocytes were directly exposed to microarray assays and RT-qPCR ("before IVM" group), or first in vitro matured and then if classified as BCB⁺ passed to molecular analyses ("after IVM" group). As a result, we have discovered substantial down-regulation of genes involved in adhesion processes, such as: organization of actin cytoskeleton, migration, proliferation, differentiation, apoptosis, survival or angiogenesis in porcine oocytes after IVM, compared to oocytes analyzed before IVM. In conclusion, we found that biological adhesion may be recognized as the process involved in porcine oocytes' successful IVM. Down-regulation of genes included in this ontology group in immature oocytes after IVM points to their unique function in oocyte's achievement of fully mature stages. Thus, results indicated new molecular markers involved in porcine oocyte IVM, displaying essential roles in biological adhesion processes.