Ne (41)
Použitá omezení
(2)
Počet nalezených dokumentů:
41
Publikováno od
do
The effect of tetrabromobisphenol a on protamination and DNA quality of mouse sperm
Žatecká, Eva; Castillo, J.; Elzeinová, Fatima; Kubátová, Alena; Děd, Lukáš; Pěknicová, Jana; Oliva, R.
2014 - anglický
Tetrabromobisphenol (TBBPA) is a widely used brominated flame retardant, currently its consumption is 210,000 tons / year and is still growing. In our previous multigenerational in vivo study we have demonstrated that TBBPA is able to induce apoptosis of testicular cells and changes in the expression of genes important for proper spermatogenesis. However the potential effect of TBBPA on epidydimal spermatozoa had not yet been investigated. Therefore, we performed further study to evaluate the effect of on sperm DNA integrity and on the protamines as the major nuclear proteins. C57Bl/6J mice pups (n=10) were exposed to TBBPA (experimental group) during the gestation, lactation, pre-pubertal and pubertal periods up to the age of 70 days and compared control mice pups (n= 10) which were not exposed. Our results demonstrate that TBBPA treatment results in a significantly decreased P1/P2 ratio, increased total protamine/DNA ratio and increased DNA fragmentation observed between TBBPA and control mice, respectively. Protamines have recently been connected to the epigenetic marking of sperm chromatin in human and mouse spermatozoa. Thus, our findings suggest that TBBPA exposure, in addition to result in increased sperm DNA damage, may also alter the epigenetic marking of sperm chromatin.
Klíčová slova:
tetrabromobisphenol A; protamine; spermatozoa
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
The effect of tetrabromobisphenol a on protamination and DNA quality of mouse sperm
Tetrabromobisphenol (TBBPA) is a widely used brominated flame retardant, currently its consumption is 210,000 tons / year and is still growing. In our previous multigenerational in vivo study we have ...
Effect of exposure to bisphenol A on gene expression in the testicular tissue in male mice
Dorosh, Andriy; Elzeinová, Fatima; Žatecká, Eva; Kubátová, Alena; Pěknicová, Jana
2014 - anglický
Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic Bisphenol A (BPA) is a synthetic, endocrine-disrupting compound able to directly bind estrogen receptors. Free BPA has been detected in human samples indicating that humans are internally exposed to BPA. The purpose of this study was to analyse the effect of BPA on the male reproductive system and testicular gene expression in germ cells. We studied the influence of long-term low concentration BPA exposition on male fertility in vivo in a two-generation study in C57BL/6 mouse strain. In this work, BPA was added with water at two environmentally relevant concentrations: 0, 4 and 4 µg/l. We measured the reproductive organs weight and sperm cells morphology and quality. Expression of genes involved in endocrine regulation and energy metabolism in testis was analysed after BPA exposure. Next, the epigenetic mechanisms of gene expression and regulation during the germ cell differentiation and effect of BPA will be analysed.
Klíčová slova:
bisphenol A; gene expression; testicular tissue
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Effect of exposure to bisphenol A on gene expression in the testicular tissue in male mice
Laboratory of Reproductive Biology, Institute of Biotechnology, Academy of Sciences of the Czech Republic, v.v.i., Prague, Czech Republic Bisphenol A (BPA) is a synthetic, endocrine-disrupting ...
Detection of mannosidase in the porcine urogenital tract – study of the sperm releasing from oviductal reservoir
Maňásková, Pavla; Ren, Š.; Jelínková, Jitka; Krejčová, T.; Liberda, J.
2014 - anglický
One of the most important steps of reproduction process is the meeting of sperm with oocyte. Binding of sperm with oviductal cells maintains spermatozoa in fertile state. The beginning of sperm capacitation is associated with oocyte ovulation resulting in the sperm release from oviductal reservoir. Hormonal changes after ovulation probably induce distinct oviductal secretion leading to disruption of the sperm protein binding with oviductal saccharide moieties. Another eventuality of the sperm releasing from oviductal reservoir is a change of oviductal environment caused by components of follicular fluid transported with oocyte after ovulation. In the pig, previous studies indicate lectin-type interaction of sperm protein receptors by mannose structures on the surface of oviductal cells. Our study was focused on enzymatic activity of mannosidase and its detection in porcine oviduct (fluid and tissue) and follicular fluid during hormonal cycle. In fluid from follicles in early and late hormonal stages, we measured mannosidase activity by colorimetric methods at physiological and acidic pH. Expression of secreted mannosidase was studied by specific antibody in follicular and oviductal fluids, and oviductal tissues during hormonal cycle. Clearly increased enzymatic activity of secreted mannosidase was found as specific-species in porcine fluid from follicles in late stage of hormonal cycle. On the other hand, detection of secreted mannosidase in follicular fluid as well as in oviductal fluid did not shown any significant differences during hormonal cycle. In oviductal isthmic tissue, we detected decreased protein expression of secreted mannosidase at middle and late follicular phases. These results suggest possible role of follicular mannosidase rather than oviductal one in the sperm releasing from oviductal reservoir in the pig. The additional study of the gene expression of secreted form of mannosidase in oviductal tissue during hormonal cycle should be necessary.
Klíčová slova:
mannosidase; oviductal reservoir; follicular fluid; enzymatic activity
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Detection of mannosidase in the porcine urogenital tract – study of the sperm releasing from oviductal reservoir
One of the most important steps of reproduction process is the meeting of sperm with oocyte. Binding of sperm with oviductal cells maintains spermatozoa in fertile state. The beginning of sperm ...
Expression of estrogen receptor beta (ERβ) In murine male reproductive tract and sperm
Dostálová, Pavla; Děd, Lukáš; Dorosh, Andriy; Elzeinová, Fatima; Pěknicová, Jana
2014 - anglický
Estrogens are steroid hormones that play an important role in reproduction of both sexes. In male, the main source of estrogens are testes where both somatic and germ cells are responsible for testosteron conversion to estrogens. Estrogens are involved in control of spermatogenesis, fluid reabsorption in rete testis and epididymis, and in later maturation steps that sperm undergo in female genital tract (capacitation, acrosome reaction). Generally, estrogen action is mediated through binding to estrogen receptors (ERs) which than lead to classical genomic or rapid non-genomic signaling. Nowadays, two classical estrogen receptors are known – ERα and ERβ. ERβ is a predominant variant in testes, while ERα is more abundant in rete testis and initial segment of epididymis. In addition to classical ERs, several splice variants that can differ in their ligand- or DNA-binding properties were detected in different tissues and cell lines. ERs mostly work as a dimer (homo- and hetero-) and splice variants often „only“ modulate function of classical full-length ERs. Therefore, estrogen action seems to be a very complex. To contribute to understanding of estrogen action in male, we detected ERβ and its potential splice variants in mice testis, epididymis and sperm. According to our results, two variants are present in all analysed tissues and cells. These variants differ in one exon in ligand binding domain which leads to different affinity for estrogens. To analyse these variants also at a protein level, we prepared specific monoclonal antibodies recognizing particular variant of ERβ. Both atibodies detected band(s) in protein extracts from testes or epididymis. Taking together, there are at least two variants of ERβ in mice testes, epididymis and sperm and it seems that both variants are similar in abundance within the same organ or sperm.
Klíčová slova:
estrogene receptor beta; spermatozoa; splice variant
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Expression of estrogen receptor beta (ERβ) In murine male reproductive tract and sperm
Estrogens are steroid hormones that play an important role in reproduction of both sexes. In male, the main source of estrogens are testes where both somatic and germ cells are responsible for ...
Panel of monoclonal antibodies – alternative tool For monitoring of sperm–zona pellucida receptors localization and identification
Zigo, Michal; Dorosh, Andriy; Pohlová, Alžběta; Jonáková, Věra; Šulc, Miroslav; Maňásková-Postlerová, Pavla
2014 - anglický
Primary binding of the sperm to the zona pellucida (ZP) is one of the many steps necessary for successful fertilization in all sexually reproducing species. Sperm bind ZP by means of membrane receptors which recognize carbohydrate moieties on ZP glycoproteins according to a well-precised sequential process. Primary-binding receptors are localized throughout the acrosomal region of the sperm surface of which many have been disclosed in various mammals. For the monitoring sperm-zona pellucida receptors in terms of localization and characterization - panel of monoclonal antibodies against proteins from the sperm surface was prepared. Antibodies were screened by immunofluorescence and Western blotting for protein localizations and competence of antibodies, respectively. Antibodies recognizing proteins localized on the sperm head and simultaneously detected by Western blot were further studied by means of immunolocalization in reproductive tissues and fluids, binding to ZP, immunoprecipitation and protein identification using MS analysis. Out of 17 prepared antibodies, 8 antibodies were simultaneously recognizing proteins localized on the sperm head and detecting proteins of interest by Western blotting. Further only 3 antibodies recognized proteins which also coincided in binding to ZP. These 3 antibodies were used for immunoprecipitation, and further protein identification of immunoprecipitates revealed that the antibodies distinguish acrosin precursor, RAB2A protein, and lactadherin P47. Acrosin and lactadherin P47 have been already detected on the sperm surface and their physiological functions in reproduction have been proposed. To our knowledge, this is the first time RAB2A has been found on the surface of sperm and its physiological function in the process of fertilization remains undisclosed.
Klíčová slova:
monoclonal antibody; zona pellucida; acrosin precursor; RAB2A; lactahedrin P47
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Panel of monoclonal antibodies – alternative tool For monitoring of sperm–zona pellucida receptors localization and identification
Primary binding of the sperm to the zona pellucida (ZP) is one of the many steps necessary for successful fertilization in all sexually reproducing species. Sperm bind ZP by means of membrane ...
Effect of diabetes mellitus on reproductive parameters in mice
Margaryan, Hasmik; Elzeinová, Fatima; Kubátová, Alena; Strolená, Eva; Pěknicová, Jana
2014 - anglický
The decrease in population fertility has become a major concern in many developed countries. Recent studies show that infertility is affecting an estimated 15% of all couples (World Health Organization, WHO, 2010). Male infertility is the primary or contributing cause in 60% of cases. Male infertility is caused by a number of factors, such as genetic background, various environmental factors and disease. Diabetes mellitus (DM), a serious health problem on its own, is also suspected to be a contributing factor to male infertility. The aim of this project was to analyze the cellular, molecular and genetic effects of diabetic environment on spermatogenesis and sperm quality and to determine the impact of DM on the in vivo reproduction, using the mouse model (Mus musculus) inbred FVB. Diabetes was induced using streptozotocin. We used our knowledge and tools (unique monoclonal antibodies developed by our group) to determine the status of reproductive organs, anogenital distance, and the quality of sperms. Genetic analysis was performed by a quantitative Reverse Transcription Polymerase Chain Reaction (qPCR). We tested selected genes which are expressed in testicular tissue and thus can influence process of spermatogenesis and consequently the sperm quality. Our preliminary data strongly suggest that DM impairs male fertility. We have found significant changes in the body and reproductive organ weight of mice with DM. We have identified qualitative and quantitative changes in the expression of proteins in epididymal fluid and sperms. We have also detected an increased number of apoptotic cells in sperm of diabetic mice compared to the control group. To our knowledge, there is no study assessing the correlation between DM and “unexplained infertility”. In view of this, it is essential to analyze the effects of DM on male fertility, sperm quality, and reproduction parameters.
Klíčová slova:
diabetes mellitus; monoclonal antibody; reproduction
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Effect of diabetes mellitus on reproductive parameters in mice
The decrease in population fertility has become a major concern in many developed countries. Recent studies show that infertility is affecting an estimated 15% of all couples (World Health ...
Changes in the expression of selected testicular genes in mice
Valášková, Eliška; Margaryan, Hasmik; Žatecká, Eva; Pěknicová, Jana
2014 - anglický
The decrease in population fertility has become a major concern in many developed countries. Recent studies show that infertility is affecting an estimated 15% of all couples (World Health Organization, WHO, 2010). Male infertility is the primary or contributing cause in 60% of cases. Male infertility is caused by a number of factors, such as genetic background, various environmental factors and disease. Diabetes mellitus (DM), a serious health problem on its own, is also suspected to be a contributing factor to male infertility. The aim of this project was to analyze the cellular, molecular and genetic effects of diabetic environment on spermatogenesis and sperm quality and to determine the impact of DM on the in vivo reproduction, using the mouse model (Mus musculus) inbred FVB. Diabetes was induced using streptozotocin. We used our knowledge and tools (unique monoclonal antibodies developed by our group) to determine the status of reproductive organs, anogenital distance, and the quality of sperms. Genetic analysis was performed by a quantitative Reverse Transcription Polymerase Chain Reaction (qPCR). We tested selected genes which are expressed in testicular tissue and thus can influence process of spermatogenesis and consequently the sperm quality. Our preliminary data strongly suggest that DM impairs male fertility. We have found significant changes in the body and reproductive organ weight of mice with DM. We have identified qualitative and quantitative changes in the expression of proteins in epididymal fluid and sperms. We have also detected an increased number of apoptotic cells in sperm of diabetic mice compared to the control group. To our knowledge, there is no study assessing the correlation between DM and “unexplained infertility”. In view of this, it is essential to analyze the effects of DM on male fertility, sperm quality, and reproduction parameters.
Klíčová slova:
diabetes mellitus; gene expression; reproduction
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Changes in the expression of selected testicular genes in mice
The decrease in population fertility has become a major concern in many developed countries. Recent studies show that infertility is affecting an estimated 15% of all couples (World Health ...
The ubiquitin–proteasome system is involved in the regulation of activity of spermadhesin aqn1 and acrosin inhibitor, the two sperm surface proteins, during porcine fertilization
Jonáková, Věra; Yi, Y.J.; Postlerová, Pavla; Pěknicová, Jana
2014 - anglický
The spermadhesin AQN1and acrosin inhibitor (AI/SPINK2) proteins bind to the sperm plasma membrane at ejaculation. The AQN1 has been implicated in sperm binding to zona pellucida (ZP) of the oocyte as well as in sperm interactions with the epithelium of the oviductal sperm reservoir. The SPINK2 protects spermatozoa from proteolytic degradation during their trip up the female genital tract toward the oocyte. This study examined the role of two components of the 19S proteasome regulatory complex, the ubiquitin C-terminal hydrolase UCHL3 and PSMD8 in the AQN1-mediated boar sperm binding to zona pellucida. Interaction of PSMD4 subunit with the acrosomal surface-associated acrosin inhibitor AI/SPINK2 provided another line of evidence for the presence of 26S proteasomes on the sperm surface. Detection of the ubiquitinated forms of SPINK2 supports the hypothesis that SPINK2 activity is controlled by ubiquitin-proteasome system (UPS). The activity of the porcine AQN1, and thus the efficiency of sperm-oocyte recognition/binding, may be controlled by elements of the sperm surface-bound UPS, in particular by UCHL3, and by proteasomal regulatory complex subunit PSMD8. Ubiquitinated isoforms of AQN1 were also detected in boar sperm extracts. The UCHL inhibitor ubiquitin aldehyde and the antibodies against UCHL3 or PSMD8 increased the rate of sperm-ZP penetration and polyspermy during porcine in vitro fertilization (IVF). In contrast, the addition of recombinant UCHL3 to fertilization medium significantly reduced polyspermy rates, while maintaining satisfactory rate of monospermic fertilization (~50%). These results are significant for production agriculture. The high level of polyspermy that hinders porcine IVF for commercial embryo transfer could be mitigated by the modulation of the UCHL3 and/or PSMD8 activity.
Klíčová slova:
ubiquitin-proteasome system; acrosin inhibitor; spermadhesin AQN1
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
The ubiquitin–proteasome system is involved in the regulation of activity of spermadhesin aqn1 and acrosin inhibitor, the two sperm surface proteins, during porcine fertilization
The spermadhesin AQN1and acrosin inhibitor (AI/SPINK2) proteins bind to the sperm plasma membrane at ejaculation. The AQN1 has been implicated in sperm binding to zona pellucida (ZP) of the oocyte as ...
Endocrine disruptors induce transgenerational alterations of the male reproductive parameters and mirna expression profiles in mouse primordial germ cells
Děd, Lukáš; Brieno-Enríquez, M.A.; García-López, J.; Cárdenas, D.B.; Guibert, S.; Hourcade, J.de D.; Pěknicová, Jana; Weber, M.; del Mazo, J.
2014 - anglický
Primordial germ cells (PGCs) are the embryonic precursors of the germ cell linage, which are restricted to form only sperm and oocytes following their specification from pluripotent cells. PGC precursors are specified in the epiblast around 6.25 days post coitum (dpc), and around 7.25 dpc become identifiable in a 40 cell-cluster. In the present study, we used a mouse model to evaluate the trans-generational (F1-F3) effects of vinclozolin (VCZ) administrated in two doses on male reproductive parameters. We observed decreased fertility rate, higher apoptotic rate and histopathologic alterations in adult testis, PGC number reduction, increments of PGCs apoptosis and changes in PGCs gene expression among all three generations. In the attempt to clarify the trans-generational transmition of the altered phenotypes, we performed the microRNA expression and DNA methylation analysis. We observed the significant alteration in the expression of multiple microRNA and microRNA-regulated genes which are important for PGCs specification, including LIN28, let-7 and BLIMP1. Trans-generational deregulation in the expression of factors involved in the Lin28-let-7-Blimp1 pathway can lead to specific VCZ-induced phenotype observed in our study.
Klíčová slova:
endocrine disruptor; miRNA expression; primordial germ cells; vinclozolin; DNA methylation
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Endocrine disruptors induce transgenerational alterations of the male reproductive parameters and mirna expression profiles in mouse primordial germ cells
Primordial germ cells (PGCs) are the embryonic precursors of the germ cell linage, which are restricted to form only sperm and oocytes following their specification from pluripotent cells. PGC ...
METODICKÉ DOPORUČENÍ PRO VYKAZOVÁNÍ SKUTEČNÝCH ZPŮSOBILÝCH NEPŘÍMÝCH NÁKLADŮ NA PROJEKT PRO ÚSTAVY AV ČR
Škoda, Jan; Starosta, Karel
2012 - český
Metodické doporučení si klade za cíl formulovat společné možné zásady pro pracoviště AV ČR týkající se alokace nepřímých nákladů na projekty a to především s ohledem na pravidla poskytovatelů, kteří přiřazování nepřímých nákladů metodou full cost vyžadují. Metodika vychází z obvyklých hospodářských a účetních postupů ústavů AV ČR. Navrhované řešení je založeno na maximální jednoduchosti a efektivnosti s cílem minimálního navýšení nepřímých nákladů zapříčiněných užíváním této metodiky, umožňuje zakončení hospodářského roku v řádném termínu a vykázání potřebných dat poskytovatelům. The aim of the Methodical Recommendation is to create possible common principles for institutes of the Academy of Sciences of the Czech Republic (AS CR) concerning the allocation of indirect costs to projects, considering mainly the rules of fund providers requesting reporting of real costs via full cost methodology. Proposed methodology is based on usual management and accounting practices of institutes of AS CR and lie in principles of maximum simplicity and effectiveness. It should result in minimum increase of real indirect costs caused by application of such methodology, it enables closing of economic year on time and also reporting of necessary data to fund providers.
Klíčová slova:
AS CR; overheads; indirect costs; full cost
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
METODICKÉ DOPORUČENÍ PRO VYKAZOVÁNÍ SKUTEČNÝCH ZPŮSOBILÝCH NEPŘÍMÝCH NÁKLADŮ NA PROJEKT PRO ÚSTAVY AV ČR
Metodické doporučení si klade za cíl formulovat společné možné zásady pro pracoviště AV ČR týkající se alokace nepřímých nákladů na projekty a to především s ohledem na pravidla poskytovatelů, kteří ...
NUŠL poskytuje centrální přístup k informacím o šedé literatuře vznikající v ČR v oblastech vědy, výzkumu a vzdělávání. Více informací o šedé literatuře a NUŠL najdete na webu služby.
Vaše náměty a připomínky posílejte na email nusl@techlib.cz
Provozovatel
Zahraniční báze