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  • Author: Maciej Zabel x
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The Contribution of Endothelial Marker Proteins in the Determination of Vascular Angiogenic Potential, in Normal Physiological Conditions and in Neoplasia

Summary

Recently, the most significant studies in the field of angiogenesis are related to trials concerning the evaluation of the prognostic significance of endothelial markers. By using an estimation of the expression of endothelial cell markers, immunohistochemical studies can assess for the continuity of the vascular intima, as well as allow for the distinction of early, late and mature forms of endothelial cells. The determination of the endothelial cell phenotype using markers such as CD34, CD31, CD133, e-NOS and von Willebrand factor may provide a valuable tool for the monitoring of both normal physiology as well as neoplastic diseases.

Open access
Innovative Methods of Archiving, Presentation and Providing Access to Histological Sections

Summary

The dynamic development of technical sciences and informatics makes now possible acquisition of microscopic images of histological sections, not only using digital cameras, but also through specialized devices called scanners. The digitalized images stored in a computer storage device are called virtual slides and, together with special software, are known as virtual microscopy. The virtual slides can be analyzed on a computer screen by panoramic viewing or using a detailed image examination at higher magnification. In many research and education institutions in both the U.S. and Europe, the virtual microscopy is used for teaching and training purposes. In the academic year of 2009/10, Department of Histology and Embryology, University of Medical Sciences in Poznan, as one of the first in Poland, has created a virtual database for educational purposes. This database created by archiving the traditional images of histological slides in the form of digital images. So far, more than 130 virtual slides have been acquired and catalogued in 24 thematic folders, available for medical students participating in histology, embryology and cell biology courses.

Telepathology is the second branch which uses virtual microscopy. Virtual microscope allows to discuss and resolve medical/diagnostic problems with the use of telecommunication systems and information technology. The existing internet platforms offer access to virtual microscopes and virtual slides. In June, 2011 the Center of Morphologic Images Archivization and Digital Database of Microscopic Pictures in the Department of Histology and Embryology, Poznan University of Medical Sciences has launched an online platform (www.caom.pl), aimed to provide the central database of scanned histological sections of physiological tissues, and pathological, rare and sporadic lesions, including tumor

Open access
Selected Aspects of Angiogensis in Haematological Malignancies

Summary

It is well established that angiogenesis is necessary in solid tumours development. Interesingly, the role of angiogensis in haematological malignancies has been also recognized. Recent publicationts indicate that microvessel density in bone marrow and angiogenic factors like endoglin, placental growth factor and cyclooxygenase 1 are increased in lymphoproliferative disorders and suggest that angiogensis is a part of pathomechanism of these malignancies. However, it has not been identified how angiogenesis can be involved in progression of haematological disorders. There is a strong need for further investigations in this area, since antiangiogenic therapy is a potential adjunct to conventional therapy of lymphoproliferative disorders.

Open access
Characteristic of factors influencing the proper course of folliculogenesis in mammals

Abstract

Folliculogenesis is the process of ovarian follicle formation,, taking presence during foetal period. During the follicular development, oogoniums undergo meiosis and oocytes are formed. In the ovaries of new born sows, primary and secondary follicles are present and, 90 days after birth, tertiary follicles appear. During development in the ovarian follicles growth of granulosa cells and differentiation of the thecal cells can be observed. A cavity filled with follicular fluid appears. Granulosa cells are divided into: mural cells and corona radiata, which together with the oocyte form the cumulus oophorus. Corona radiata cells, mural layers and oolemma contact each other by a network of gap junctions. Secreted from the pituitary gland, FSH and LH gonadotropin hormones act on receptors located in granular and follicular cells. In the postnatal life tertiary follicles and Graafian follicles are formed. When the follicle reaches a diameter of 1 mm, further growth depends on the secretion of gonadotropins. Mature ovarian follicles produce: progestins, androgens and oestrogens. The growth, differentiation and steroidogenic activity of ovarian follicles, in addition to FSH and LH, is also affected by prolactin, oxytocin, steroid and protein hormones, numerous proteins from the cytokine and interleukin family, metabolic hormones like insulin, glucocorticoids, leptin, thyroid hormones and growth hormones. Despite numerous studies, many processes related to folliculogenesis have not been discovered Learning the mechanisms regulating reproductive processes would allow to easily distinguish pathological processes and discover more and more genes and mechanisms of their expression in cells that build ovarian follicles.

Open access
Cytoplasmic and nuclear maturation of oocytes in mammals – living in the shadow of cells developmental capability

Abstract

The pig is a polyestrous animal in which the ovarian cycle lasts about 21 days and results in ovulation of 10-25 oocytes. Ovum reaches 120-150 μm in diameter, with the surrounding corona radiata providing communication with the environment. The zona pellucida is composed of glycoproteins: ZP1, ZP2, ZP3. In the course of oogenesis, RNA and protein accumulation for embryonic development occurs. Maternal mRNA is the template for protein production. Nuclear, cytoplasmic and genomic maturity condition the ability of the ovum to undergo fertilization. There are several differences in protein expression profiles observed between in vitro and in vivo conditions. Oogenesis is the process of differentiating female primary sex cells into gametes. During development gonocytes migrate from the yolk sac into the primary gonads with TGF-1, fibronectin, and laminin regulating this process. Cell cycle is blocked in dictyotene. Primary oocyte maturation is resumed before each ovulation and lasts until the next block in metaphase II. At the moment of penetration of the sperm into the ovum, the metaphase block is broken. The oocytes, surrounded by a single layer of granular cells, form the ovarian follicle. The exchange of signals between the oocyte and the cumulus cells done by gap-junctions, as well as various endo and paracrine signals. The contact between the corona radiata cells provides substances necessary for growth, through the same gap junctions. Studies on follicular cells can be used to amplify the knowledge of gene expression in these cells, in order to open way for potential clinical applications.

Open access
Pathogenesis and pathophysiology of ovarian follicular cysts in mammals

Abstract

Ovarian cysts remain to be one of the most common and serious problems in reproduction of farm animals, as well as humans. Apart from causing the fall in reproductive potential of the ovaries, occupying the place in which folliculogenesis and oogenesis occur, they also cause hormone imbalances, by preventing corpus luteum formation, hence lowering the amount of steroid hormone production. While singular cysts rarely affect fertility, hormone fluctuations that are associated with their presence promotes their multiplication, which usually has more adverse effects. While the cysts are easily detectable in humans, possessing distinct echography while examined by ultrasound, multiple factors prevent widespread use of effective detection methods among large herds of farm animals. Because of lack of noticeable symptoms of early stages of such malignancies, they rarely get detected before the animal stops to exhibit symptoms of heat. That causes scientific research to be focused on not only methods of detection, but also the ways to negate the effects of ovarian cysts and bring the affected specimen back to reproductive potential. Despite that, high costs of diagnosis and treatment, cause them to be uncommon on commercial farms. As lack of fertility eliminates animals from breeding purposed herds, ovarian cysts persist as a cause of large losses of the animal husbandry business. Continuous research, focused on natural examples of ovarian cysts should be conducted, in order to improve methods of detection, prevention, treatment and recovery from the effects of ovarian cysts.

Open access
Genes regulating biochemical pathways of oxygen metabolism in porcine oviductal epithelial cells during long-term IVC

Abstract

Oxygen metabolism has an important role in the normal functioning of reproductive system, as well as the pathogenesis of female infertility. Oxidative stress seems to be responsible for the initiation or development of reproductive organ diseases, including polycystic ovary syndrome, endometriosis, preeclampsia, etc. Given the important role of maintaining balance between the production of ROS and antioxidant defence in the proper functioning of reproductive system, in the present study we aimed to analyse the expression of genes related to oxygen metabolism in porcine oviductal epithelial cells during long-term in vitro culture. The oviducts were collected from 45 crossbred gilts at the age of approximately nine months that displayed at least two regular oestrous cycles. The oviductal endothelial cells were isolated by enzymatic digestion to establish long-term primary cultures. Gene expression changes between 7, 15 and 30 daysof culturewere analysed with the use ofwhole transcriptome profiling by Affymetrix microarrays. The most of the “cellular response to oxidative stress” genes were upregulated. However, we did not observe any main trend in changes within the “cellular response to oxygen-containing compound” ontology group, where the gene expression levels were changed in various manner.

Running title: Oxygen metabolism in porcine oviductal epithelial cells

Open access
The differentiation and transdifferentiation of epithelial cells in vitro – is it a new strategy in regenerative biomedicine?

Abstract

In modern medical research, stem cells are one of the main focuses, believed to be able to provide the solution to many currently unsolvable medical cases. However, their extraordinary potential for differentiation creates much obstacles in their potential application in clinical environment, without understanding the whole array of molecular mechanisms that drive the processes associated with their development and maturation. Because of that, there is a large need for studies that concern the most basic levels of those processes. Progenitor stem cells are a favorable target, as they are relatively lineage committed, making the amount of signaling required to reach the final form much lower. Their presence in the adult organism is also an advantage in their potential use, as they can be extracted without the need for storage from the moment of pre-natal development or birth. Epithelial tissues, because of their usual location or function, exhibit extraordinary level of plasticity and proliferative potential. That fact makes them one of the top candidates for use in applications such as tissue engineering, cell based therapies, regenerative and reconstructive medicine. The potential clinical application, however, need to be based on well developed methods, in order to provide an effective treatment without causing major side effects. To achieve that goal, a large amount of research, aiming to analyze the molecular basics of proliferation and differentiation of epithelial stem cells, and stem cells in general, needs to be conducted.

Open access
Analysis of fructose and mannose – regulatory peptides signaling pathway in porcine epithelial oviductal cells (OECs) primary cultured long-term in vitro

Abstract

The morphological and biochemical modification of oviductal epithelial cells (OECs) belongs to the compound process responsible for proper oocytes transport and successful fertilization. However, the main mechanisms which regulated this process are still not entirely known. Moreover, the OECs metabolism, which may be identified as the “cellular activity” marker, is poorly recognized. In this study we investigated the fructose and mannose metabolic pathway in porcine OECs primary long-term cultured in vitro.

In our study, we employ a primary long term in vitro culture (IVC) and microarray approach (the Affymetrix microarray were used for analysis of transcriptomic profile of OECs) for expression levels analysis.

We found that from the whole analyzed transcriptome, 1537 genes were upregulated and 995 were down regulated after 7 days of culture, 1471 genes were upregulated and 1061 were downregulated after 15 days of culture and 1329 genes were upregulated and 1203 were downregulated after 30 days of culture. Moreover, the differential expression of SORD, FPGT, PFKFB4, TPI1, MPI, ALDOC, HK2 and PFKFB3 at 24 hours, 7 day, 15 day and 30 day, was also observed.

We suggested that fructose and mannose metabolism may be important molecular bio-marker of porcine OECs capability in in vitro model. The metabolic profile is significantly accompanied by cells proliferation in vitro. The transcriptomic profile of SORD, FPGT, PFKFB4, TPI1, MPI, ALDOC, HK2 and PFKFB3 expression may be identified as “fingerprint” of fructose and mannose metabolism in OECs as well as involved in cellular in vitro developmental capacity in pigs.

Open access
Positive Regulation of Macromolecule Metabolic Process Belongs to the Main Mechanisms Crucial for Porcine Oocytes Maturation

Summary

The mammalian oocytes maturation is the compound process that involves morphological and molecular changes. These modifications include storage of macromolecules, which are crucial for proteins biosynthesis during periimplantation stages of embryo development. This study was aimed to investigate the genes expression profile encoding macromolecules important for regulation of proper porcine oocytes maturation.

The porcine oocytes were collected from large ovarian follicles and analyzed both before and after in vitro maturation (IVM). Additionally, to check the developmental competence status, brilliant crezyl blue test (BCB) was performed. The obtained cDNA was used for biotin labeling and fragmentation by AffymetrixGeneChip® WT Terminal Labeling and Hybridization (Affymetrix). The preliminary analysis of the scanned chips was performed using AffymetrixGeneAtlasTM Operating Software. The created CEL files were imported into downstream data analysis software.

In results, we found expression of 419 different genes, 379 genes were down-regulated and 40 genes were up-regulated in relation to the oocyte transcriptome before in vitro procedure. We observed up-regulation of all genes involved in “positive regulation of macromolecule metabolic process” before IVM as compared to transcriptional profile analyzed after IVM.

In conclusion, we suggested that genes encoding proteins involved in macromolecule metabolism are important for achieving of porcine oocytes maturational stage. Moreover, the “activity of macromolecules metabolism” is much more increased in immature oocytes.

Open access