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Bisphenol S influence on selected markers of meiotic maturation of porcine oocytes
Černíková, Terezie ; Petr, Jaroslav (advisor) ; Krylov, Vladimír (referee)
Bisphenol A is a widely used chemical in the manufacture of plastics. The presence of BPA in the environment adversely affects human health due to contamination of air, drinking water and food. Growing concerns about the effects of BPA have led to its regulation in production and development of alternative chemicals to BPA, such as bisphenol S (BPS). However, the effects of BPS were not properly tested before its introduction to production and the effects on human reproduction are still unknown. For this reason, it is desirable to test the effect of BPS on mammalian oocyte development. This study hypothesizes that BPS exposure causes inhibition of meiotic maturation of porcine oocytes in vitro. This study aims to investigate the potency of BPS at low concentrations corresponding to normal human exposures to selected porcine oocyte proteins. The results of this study demonstrate the negative effect of BPS on the progression of meiotic maturation and reaching the mature oocyte stage. In addition, the results show an increase in the formation of defective meiotic spindles and a disruption of mitochondrial integrity after exposure to BPS concentrations. However, the effect of BPS on double-strand breaks was not demonstrated in this study, in contrast to the case of BPA. Taken together, the results show...
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Study of the variations in the expression of different adhesion and cytoskeletal proteins of podocytes (E-Cadherin, Podocin, Vimentin) due to Bisphenol A
Chvojanová, Zuzana ; Kovařík, Miroslav (advisor) ; Němečková, Ivana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové, Department of Biological and Medical Sciences The University of Alcalá, Faculty of Medicine, Department of biomedicine and biotechnology Student: Zuzana Chvojanová Supervisor: PharmDr. Miroslav Kovařík, Ph.D. Consultant: María Isabel Arenas Jimenéz Title of the diploma thesis: Study of the variations in the expression of different adhesion and cytoskeletal proteins of podocytes (E-Cadherin, Podocin, Vimentin) due to Bisphenol A Bisphenol A (BPA) is one of the most widespread compounds in the world, producing over 6 billion metric tons per year. It is widely used as part of polycarbonate plastics and epoxy resins, from which reusable plastic bottles, food boxes and some medical equipment are made. It is also used to coat the inner layer of the cans. Previous studies have shown that BPA contributes to many chronic diseases in the human body, such as kidney disease - diabetic nephropathy. Podocytes - terminally differentiated cells of the Bowman's capsule in glomerulus - are an integral part of the filtration barrier, where they play an important role in preventing the plasmatic proteins from penetrating to the urine. Therefore, in this study, we looked at the effect of BPA on these cells and their particular proteins, using both in vivo and...
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Study of the variations in the expression of different adhesion and cytoskeletal proteins of podocytes (E-Cadherin, Podocin, Vimentin) due to Bisphenol A
Chvojanová, Zuzana ; Kovařík, Miroslav (advisor) ; Němečková, Ivana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové, Department of Biological and Medical Sciences The University of Alcalá, Faculty of Medicine, Department of biomedicine and biotechnology Student: Zuzana Chvojanová Supervisor: PharmDr. Miroslav Kovařík, Ph.D. Consultant: María Isabel Arenas Jimenéz Title of the diploma thesis: Study of the variations in the expression of different adhesion and cytoskeletal proteins of podocytes (E-Cadherin, Podocin, Vimentin) due to Bisphenol A Bisphenol A (BPA) is one of the most widespread compounds in the world, producing over 6 billion metric tons per year. It is widely used as part of polycarbonate plastics and epoxy resins, from which reusable plastic bottles, food boxes and some medical equipment are made. It is also used to coat the inner layer of the cans. Previous studies have shown that BPA contributes to many chronic diseases in the human body, such as kidney disease - diabetic nephropathy. Podocytes - terminally differentiated cells of the Bowman's capsule in glomerulus - are an integral part of the filtration barrier, where they play an important role in preventing the plasmatic proteins from penetrating to the urine. Therefore, in this study, we looked at the effect of BPA on these cells and their particular proteins, using both in vivo and...
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The Impact of Selected Endocrine Disruptors on Human Spermatogenesis
Vítků, Jana
Steroid hormones in testis play an important role in spermatogenesis, maintenance of the male reproductive tract, production of semen and the maintenance of secondary sex characteristics and libido. They are also discussed as a target for substances called endocrine disruptors (EDs). No complex study was conducted on evaluation of relationships between EDs and steroid spectrum in 2 biological fluids; seminal plasma and plasma. The aim of the PhD. thesis was to develop and validate a method for determination of bisphenol A (BPA) and steroid spectrum in plasma and seminal plasma and to shed more light into mechanisms of ED action and effects of BPA and polychlorinated biphenyls (PCBs) on human spermatogenesis and steroidogenesis. Two new liquid-chromatography mass spectrometry methods for determination of BPA and 11 steroids in plasma and seminal plasma were developed and validated. The methods were used for estimation of analyte concentrations in 191 men with a different degree of fertility. Concurrently, the levels of six congeners of PCBs, gonadotropins, selenium and zinc in plasma were estimated. Partial correlations adjusted for age and BMI were calculated to evaluate relationships between these analytes. Seminal BPA, but not plasma BPA, was negatively associated with sperm concentration...
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The Impact of Selected Endocrine Disruptors on Human Spermatogenesis
Vítků, Jana ; Hill, Martin (advisor) ; Pohanka, Michal (referee) ; Lapčík, Oldřich (referee)
Steroid hormones in testis play an important role in spermatogenesis, maintenance of the male reproductive tract, production of semen and the maintenance of secondary sex characteristics and libido. They are also discussed as a target for substances called endocrine disruptors (EDs). No complex study was conducted on evaluation of relationships between EDs and steroid spectrum in 2 biological fluids; seminal plasma and plasma. The aim of the PhD. thesis was to develop and validate a method for determination of bisphenol A (BPA) and steroid spectrum in plasma and seminal plasma and to shed more light into mechanisms of ED action and effects of BPA and polychlorinated biphenyls (PCBs) on human spermatogenesis and steroidogenesis. Two new liquid-chromatography mass spectrometry methods for determination of BPA and 11 steroids in plasma and seminal plasma were developed and validated. The methods were used for estimation of analyte concentrations in 191 men with a different degree of fertility. Concurrently, the levels of six congeners of PCBs, gonadotropins, selenium and zinc in plasma were estimated. Partial correlations adjusted for age and BMI were calculated to evaluate relationships between these analytes. Seminal BPA, but not plasma BPA, was negatively associated with sperm concentration...
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Endocrine disruptors in reptiles
Semerád, Jaroslav ; Kratochvíl, Lukáš (advisor) ; Cajthaml, Tomáš (referee)
The ability of environmental contaminants to influence reproduction and development in vertebrates via disruption of the endocrine system is widespread. The mechanisms through which xenobiotics act can be complex and vary greatly among species. Reptiles are particularly good models for studying endocrine affecting compounds due to the fact that different species differ in modes of sex determination (genotypic sex determination or temperature-dependent sex determination) and parity (oviparity or viviparity). The sex of individual is often determined by egg incubation temperature, and exogenous application of steroid hormones and their analogs or steroidogenic enzyme inhibitors can reproduce effects of temperature. The lability of sex determination in some reptile species offers opportunity to use gonadal sex as a marker for effects of endocrine disrupting compounds (EDC), even for the effects of extremely low dosages of EDCs or EDC mixtures. The neonatal offsprings exposed to EDCs during embryogenesis provide yet another way to assess endocrine disruption, i.e., measurement of steroid hormone levels in their blood. In addition, many reptile species are highly aquatic, they use habitats near agricultural areas, where usage of pesticides is the most intense, and they are carnivores or scavengers. Therefore,...
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Hazardous substances leasing from plastic bottles
Najmanová, Iveta ; Vopršalová, Marie (advisor) ; Pourová, Jana (referee)
v anglickém jazyce Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Iveta Najmanová Supervisor: PharmDr. Marie Vopršálová, CSc. Title of diploma thesis: Hazardous substances that are released from plastic bottles This master thesis focuses on hazardous substances that are released from plastic bottles. Attention is paid especially to bisphenol A and antimony and their effects after oral administration. Given the fact that these substances are harmful to humans, most of the information about their effects was observed in epidemiological studies or studies conducted on laboratory animals and human tissues. The thesis documents the toxicological effects on the body, especially of bisphenol A. To a lesser extent and primarily because of the limited number of studies on this topic, it deals with the influence of antimony. This is a search thesis and the data are the sum of bibliographic records on the subject.
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Optimization of endocrine disruptors determination in wastewater treatment plant sludge and application of the method in environmental samples.
Medková, Jaroslava ; Cajthaml, Tomáš (advisor) ; Tesařová, Eva (referee)
Hormonaly active compounds in wastewaters represent nowdays a serious problem. Proceses currently used in watewater treatment plants (WWTP) are unefficient in removing these compounds from contaminated wastewaters. The compounds are supposed to sorb onto solid sludge elements and sediments. In this work seven endocrine disruptors were detected in the sludge samples from WWTPs. A new sensitive method for detection of seven selected endocrine disruptors (4-nonylphenol, bisphenol A, estriol, 17β-estradiol, estrone, 17α- ethynylestradiol, irgasan) was developed. The method is based on accelerated solvent extraction (ASE), gel permeation chromatography (GPC) and solid phased extraction. For final extract analysis, gas chromatography coupled with mass spectrometry (GC/MS) was used. The efficiency of this method was tested using artificially contaminated sludge and the method was used to analyse real samples from several WWTPs in Czech Republic. The effect of sludge age on detection of individual analytes was assessed as well. The concentrations of endocrine disruptors measured in the samples reached up to 1 µg/g. The results are comparable or higher then those reported in other works and they show the necessity of further research on endocrine disruptors in the environment.
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Application of ligninolytic fungi on solid substrates for degradation of endocrine disrupters
Slavíková - Amemori, Anna ; Cajthaml, Tomáš (advisor) ; Gabriel, Jiří (referee)
Today a lot of attention is focused on compounds called endocrine disrupters (EDs) among substances released to environment by humans. They are a group of substances which can disturb function of hormonal system of organisms including humans. Their poor removal at wastewater treatment plants (WwTP) were shown at various studies, thus they can reach the environment in water. A prospective way for the degradation of EDs at WwTP can be their removal by ligninolytic fungi. They are able to degrade lots of lignin-like aromatic substances because of their highly nonspecific enzymes. In this work growth and enzyme production capability of four ligninolytic fungal strains were monitored on three solid substrates (straw pellets, poplar sawdust mixed with straw pellets, oak sawdust with straw pellets), which may be suitable substrates for fungal growth in bioreactors for wastewater treatment. Ability of these enzymes to degrade EDs were tested in in-vitro degradation experiment. Trametes versicolor was found as best degrading strain with 20 μg/ml of bisphenol A, 17 α- ethynylestradiol and nonylphenol degraded below a quantification limit within 24 hours. Fungal strains degraded EDs well on all of the three substrates but wood sawdust seemed to be a better substrate for fungal growth because straw pellets...
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The effect of endocrine disruptors on animal reproduction
Eretová, Nikola ; Chmelíková, Eva (advisor) ; Krejčířová, Romana (referee)
Endocrine disruptors are chemicals affecting the body, disrupting the functioning of the endocrine system and thus altering the balance of physiological functions in the entire organism. There are countless endocrine disruptors in the ecosystem, in addition to accumulated substances in the environment, these elements are found in a wide range of products that we encounter on a daily basis. Most often, these materials include various plastics, such as packaging of beverages and foods. According to the presence of these chemicals, endocrine disruptors can be divided into synthetic and natural. Endocrine disruptors are characterised by a long half-live and significant bioaccumulation. These harmful substances enter the organism in various ways, for example through skin and food. Exposure of the organism to endocrine disrupters has a negative effect on its health. In a large quantity, they also affect the reproductive functions. In addition to the effect on reproduction, a negative impact was demonstrated also on other systems, such as nervous. Some endocrine disruptors have a confirmed carcinogenic effect. Endocrine disruptors work primarily through the oestrogen, androgen, progestin or aryl hydrocarbon receptors. Their combinations and metabolites are often more dangerous than the actual substances. The research of the impact of endocrine disruptors on the reproduction of animals proved their negative effect on gonads, production of gametes (spermatocyte and oocyte), fertilisation, implantation, embryonic development, completion of gravidity and birth weight; therefore the changes may occur in the entire reproductive system. Despite numerous studies examining the effect of endocrine disruptors on animal health, there are certain unexplained inconsistencies, which is why it is necessary to continue in the research intensively in the future.
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