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In vitro fertilization in horses
Müller, Filip ; Šušor, Andrej (advisor) ; Šimoník, Ondřej (referee)
Reproductive management in horse breeding increasingly relies on in vitro fertilization (IVF) techniques. This technology entails a complex process, including the acquisition of immature oocytes, their in vitro maturation, fertilization with sperm, and subsequent cultivation of the early embryo before transfer into a synchronized recipient. However, the success of equine IVF is influenced by various factors such as oocyte quality, sperm capacitation, and technical issues unique to this process, compared to other mammalian models. This bachelor's thesis aims to summarize and evaluate current knowledge on IVF of horse eggs, identify key factors influencing success, and describe current procedures for gamete preparation. By incorporating the latest IVF approaches and optimizing them, a higher success rate can be achieved. Key aspects for improving equine IVF include gamete collection and handling, in vitro oocyte maturation, sperm capacitation, and subsequent embryonic development.
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Sperm DNA damage: detection methods used in clinical practice
Tušlová, Magdaléna ; Postlerová, Pavla (advisor) ; Koubek, Pavel (referee)
The current routine semen analysis, known as a spermiogram, is not able to provide a complete picture of male fertility as it does not routinely include an assessment of DNA integrity. This parameter is closely related to difficulties during conception and increased risk of miscarriage. This paper discusses the causes of sperm DNA damage, the detection of this damage by various methods and concludes with a discussion of the possibilities of incorporating these tests into clinical practice to improve the assessment and treatment of male fertility. Mechanisms of sperm DNA fragmentation include impaired spermatogenesis, oxidative stress and impaired apoptosis, which can be influenced by genetic, anatomical and external factors. The main part of this thesis was devoted to a review of methods for the detection of sperm DNA fragmentation, including sperm chromatin structure analysis (SCSA), sperm chromatin dispersion test (SCD), TUNEL method, single-strand DNA break recognition test (ISNT), comet assay and chromatin staining. Although some of these methods are frequently used, challenges remain in their standardization and full integration into clinical practice. However, the possibility of their routine use could bring significant advances in the diagnosis and treatment of male infertility. Among the...
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Význam vitaminu D a jeho metabolitů v reprodukci živočišných organismů
Červenka, Jiří
Vitamin D is considered to be a group of molecules that have many functions in animal organisms. The best known of these is the key role in calcium and phosphorus homeostasis and regulation of bone mineralization. In recent years, however, many new functions of this vitamin have been discovered, such as the regulation of cell proliferation and differentiation, its influence on the immune system or its function in animal reproduction. This thesis deals with the importance of vitamin D in animal reproduction with an emphasis on livestock. In the literature review, the occurrence of receptors for vitamin D in cells of various types of different tissues of reproductive system, particularly in mammals and birds, and the function of various metabolites mediated by these receptors are discussed in the individual chapters. The thesis includes the design of methodology, which would test the effect of vitamin D on reproduction of the male and female domestic chickens. The hypothesis could verify, whether or not, Rhode Island Red cockerels, that would be fed a diet with a higher vitamin D content would demonstrate better ejaculate parameters and higher fertilization of eggs laid by Rhoade Island White hens inseminated with this semen. Furthemore, a solution is proposed to verify the hypothesis, assuming higher hatchability and lower embryonic mortality in hens fed higher vitamin D feed mixture. The result would be compared with hens and roosters of the same breeds, reared in an environment with the same conditions, fed a vitamin D deficient feed mixture.
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Rab proteins in sperm life
Vojtová, Kristýna ; Páleníková, Veronika (advisor) ; Zelenková, Natálie (referee)
Rab proteins are the largest group of small GTPases. They work as key regulators in the intracellular vesicular transport of cells. This bachelor's thesis contains a literature review of current information on the function of Rab proteins in mammalian spermatozoa. The first part of the work is devoted to their structure, function, cycle, and diseases related to the dysfunction of Rab proteins. The second part is focused on sperm development and maturation linked with specific Rab proteins involved in individual steps during the life of the sperm. Rab proteins are important in cytoskeletal organization and cytokinesis of sperm during spermatogenesis. They participate in the acrosome biogenesis mediated by the Golgi apparatus and the morphological changes of sperm during spermiogenesis. They also play a key role in the acrosome reaction and interaction with the zona pellucida. Due to their necessity in the sperm development and maturation, Rab proteins are proposed as a marker of male fertility, which is summarized in the last part of the thesis. Keywords Rab proteins, GTPases, sperm, spermatogenesis, spermiogenesis, fertilization, infertility
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Proteomic architecture of sperm-egg interactions
Otčenášková, Tereza ; Stopka, Pavel (advisor) ; Petr, Jaroslav (referee) ; Vrbacký, Marek (referee)
Recent advances in proteomic methods provide new insights for biological research including the field of reproductive biology. Determination of the proteomic basis of spermatozoa is pivotal for understanding the complex process of gamete interactions during fertilization such as acrosome reaction. Great differences imposed by postcopulatory sexual selection and phylogeny can be observed regarding the size, shape, and molecular composition of sperm across animal taxa. The first objective of this doctoral thesis is to characterize the protein contents of the acrosome to ascertain its further functional significance in sperm-egg interaction. Also, we aim to investigate the potential relationships between sperm protein composition and sperm morphology diversification, risk of sperm competition, and species phylogenetic background. Wild-caught males from natural populations of species of Mus musculus musculus, Apodemus flavicollis, Microtus arvalis (order Rodentia), Acrocephalus palustris, Chloris chloris, Phylloscopus collybita, Cinclus cinclus, Hirundo rustica, and Taeniopygia guttata from a captive population (order Passeriformes) were subject to the analyses. Nano-liquid chromatography with tandem mass spectrometry was applied as the main methodological approach in this thesis. Our data implicate...
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Ezrin-Radixin-Moesin (ERM) proteins: The link between tetraspanin web and cytoskeleton in gametes
Picková, Jana ; Frolíková, Michaela (advisor) ; Lánská, Eva (referee)
Ezrin, which belongs to the ERM protein family along with radixin and moesin, plays an important role in linking membrane proteins to the actin cytoskeleton. In sperm, ezrin was described so far in bovine and humans, where it probably contributes in actin polymerization during capacitation. During the acrosome reaction, actin plays a significant role in relocation of protein from the inner acrosomal membrane to the equatorial segment, which is an essential process for successful fertilization. One of the proteins that relocates to the equatorial segment, the site of initiation of gamete fusion, is protein CD9. This protein probably stabilizes protein interactions between sperm and oocyte during gamete fusion. In this diploma thesis, we focused on the role of ezrin in linking the CD9 protein to the actin cytoskeleton in mouse sperm. Using indirect immunofluorescence, we detected ezrin, CD9 and actin in acrosome intact mouse sperm. The co-localization of these proteins in the apical acrosomal region suggests their interactions. However, this was not confirmed by our co-immunoprecipitation experiments. Nevertheless, in the apical acrosomal region we also detected EWI-2 protein, which could act as linker between CD9 and ezrin. In this thesis, we also investigated changes in levels of active...
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The role of LINC complex in male germinal cells
Kmoníčková, Věra ; Komrsková, Kateřina (advisor) ; Knop, Filip (referee)
LINC (linker of the nucleoskeleton and cytoskeleton) complex is substantial for the overall function of any nuclear cell. It is a bridge between the cytoplasmic and nuclear structures which mediates transmission of mechanical forces generated on the cytoplasmic side. The main objective of this thesis is the function of distinct variants of the LINC complexes in mammalian male germinal cells throughout their development. The nuclear facing side of the LINC complex is a key player in homolog pairing and rapid chromosome movements during meiosis. The cytoplasmic facing side is necessary for the sperm head formation, proper acrosome and nucleus attachment. Evenly, another complex is essential for the head-to-tail coupling as without this one the sperm cells are found decapitated. If the subunits of the LINC complex are defective, males are afflicted with different kinds of infertilities, which nowadays is one of the important issues of our society. Many things about the role and structure of the LINC complex has been discovered due to modern technologies. These up to date findings are summarized and discussed on the following pages.
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Sperm competition in humans
Vydarená, Eliška ; Havlíček, Jan (advisor) ; Tomášek, Oldřich (referee)
Sperm competition has been observed and studied many times in a lots of animal species. It is currently also being considered in humans. Despite the number of studies, most of them were mainly focused on insects and birds. So far, only a small number of studies have dealt with sperm competition research in humans. For this reason, the question if sperm competition appeared and had selection pressure for the creation of various adaptations even in human evolution remains a controversial topic. In this bachelor thesis, I summarize the current knowledge of sperm competition in humans, the frequency of extra-pair copulation and paternity, and in individual chapters to indicate what adaptations to sperm competition may have developed in humans during their development. Key words Sperm competition, human sexuality, sperm, reproductive strategies
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Gonadal development during the lifetime of the fastest maturing model vertebrate- turquoise killifish (Nothobrachius furzerí)
LANDOVÁ, Magdaléna
Turquoise killifish had to adapt to the inhospitable conditions in which they live, especially drying temporal water bodies, which means certain death. The life sprint of the representatives of this genus is at its peak within one-month post-hatching, when both sexes have fully developed gonads and can reproduce. This rate comes with a high cost, as the killifish gonads begin to show signs of tissue degradation and germ cell apoptosis as early as three months post-hatching. Germ cell loss increases with age. A description of the development and degradation of the gonads in males and their breeding was elaborated. For the evaluation of aging-specific changes, immunochemical methods were used, focusing on the binding of specific antibodies against target epitopes and their visualization using fluorescence microscopy. Procedures for histological specimens have also been described, both for classical light and fluorescence microscopy.
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Cambarellinae: Trpaslíci ve světě račích spermií?
TOMAN, Jan
Recently, the ultrastructure of crayfish spermatozoa has become an increasingly studied topic. Up to now, the ultrastructure has been studied and defined in about fifteen species of freshwater species from all four crayfish families, however it has not yet been studied in a group of dwarf crayfish (subfamily Cambarellinae). Present work aimed to describe the spermatozoa ultrastructure of two dwarf crayfish species, specifically the Orange dwarf crayfish Cambarellus patzcuarensis and the Texas dwarf crayfish C. texanus. These species were then compared with the species already studied using morphological traits and biometric data. The ultrastructure of their spermatozoa shows commonly known patterns that include the acrosome and subacrosome in the front and the nucleus on the opposite side of the cell . Furthermore, radial arms typical for the superfamily Astacoidea that wrap around the nucleus and the whole cell enclosed by the extracellular capsule. The results show that the size of the acrosomes of Parastacidae membres is the smallest, while the crayfish of the Astacidae family show the largest acrosome. The current study points out a medium-sized acrosome of dwarf crayfish and Cambaridae in general, although they are located at the lower margin of this family with the Brazos crayfish being close to representatives of the Parastacidae. In conclusion, it is important to say that the combination of the morphological traits and biometric data of sperm acrosomes allows distinguishing individual crayfish groups to a large extent. This study may help to identify other species that have not been studied so far and could be a valuable basis for subsequent research of the ultrastructure and biometrics of crayfish spermatozoa.
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