Micro-pollutants such as 17β-estradiol (E2) have been detected in different water resources and their negative effects on the environment and organisms have been demonstrated. It is essential to confirm the presence of micro-pollutants in different environments by biosensors and to remove these compounds. In this thesis, E2-binding target structures were used to investigate the underlying binding properties. E2-binding protein, DNA-, and PNA-aptamere (peptide nucleic acid) structures were used as targets to determine physicochemical interactions. The protein dataset consist of 35 publicly accessible three-dimensional structures of E2-protein complexes, from which six representative binding sites could be selected. There is no three-dimensional structure information for an E2-specific DNA aptamer, thus it was modeled using a coarse-grained modeling method. Using sequence information additional DNA aptamers were modeled. The E2 ligand was positioned close to the potential binding area of the aptamer structures, the underlying complexes were investigated by a molecular dynamics simulation, and the interactions were examined by an interaction profiler tool for each time step. A PNA generator was developed that can convert DNA and RNA in silico to more robust, but chemically equivalent PNA. This generator was used to transform the E2-specific DNA aptamer into PNA for binding studies with E2. All formed complexes were investigated with respect to the following non-covalent interaction types: hydrogen bonds, water-mediated hydrogen bonds, π-stacking, and hydrophobic interactions. Ten functional groups could be derived which formed the conserved interactions to E2. The study contributes to the understanding of the behavior of ligands that bind through different target structures in an aqueous solution and to the identification of binding specific interaction partners. The results of this thesis can be used to design novel synthetic receptor and filter systems.

Stroke is a common and multifactorial disease influenced by genetic and environmental risk factors. It is a highly heterogeneous entity consisting of two main types, ischemic (80%) and hemorrhagic (20%) stroke. The most common form of hemorrhagic stroke is intracerebral hemorrhage (ICH). Ischemic stroke mainly results from thrombotic or embolic events, while ICH is caused by the rupture of an artery in the brain. The mean age of first-ever stroke is 75 years (73 vs. 78 years, for men and women, respectively) and the age-specific stroke incidence is higher for men as compared to women, suggesting that hormonal factors confer protection. A large body of experimental and observational studies shows that estrogens exert beneficial effects in the cardiovascular system. However, large, recent, clinical randomized trials have failed to demonstrate a lower risk of stroke with hormone replacement therapy (HRT) in elderly postmenopausal women. It is possible that HRT may only protect a subgroup of women. Here, genetic predisposition might be involved. Stroke incidence is 50% higher in northern compared to southern Sweden, suggesting a genetic predisposition in this population. This relatively homogeneous population displays founder effects, making it well suited for genetic studies. Since 1985, the MONICA and VIP projects have conducted large-scale cardiovascular health surveys in this population. Information about conventional stroke risk determinants and also DNA have been collected, and two prospective, nested case-referent cohorts (113 cases and 226 controls; 275 cases and 549 controls) have been sampled. To investigate whether genes of the estrogen signaling system may be important in stroke development, we performed genetic association studies, including specific functional single nucleotide polymorphisms in the genes for estrogen receptor alpha (ERα, ESR1), and its target genes osteoprotegerin (OPG, TNFRS11B) and interleukin-6 (IL-6, IL6). We found a significant association between the common c.454-397T/T genotype in ESR1 and ICH, remaining after adjustments for conventional stroke risk factors. The c.454-397T/T genotype also associated with increased systolic (SBP) and diastolic blood pressure (DBP). The combination of c.454- 397T/T and either hypertension, increased SBP, or increased DBP boosted this association substantially and significant synergistic effects on ICH risk between this genotype and increased blood pressure were demonstrated. In a second study, we found a similar association between the common OPG-1181C/C genotype and ICH. Cognitive impairments, including spatial memory and learning deficiencies, are common after stroke. Estrogens improve cognitive functions, including memory and learning processes, in postmenopausal women and ovariectomized rodents. Post-ischemic housing of rats in an enriched environment (EE) improves recovery of spatial memory and learning impairments. Both estrogen and EE induce neuroplasticity in the hippocampus. We hypothesized that 17β- estradiol combined with EE would accelerate recovery after experimental focal brain ischemia in ovariectomized rats and that such improvements could be related to expression of nerve growth factor-induced gene A (NGFI-A) in the hippocampus. Five to six weeks after middle cerebral artery occlusion, 17β-estradiol–treated rats housed in an EE showed significant improvements in cognitive function (i.e., shorter latency and path in the Morris water maze task) and significantly higher NGFI-A mRNA expression in bilateral cornu ammonis 1 (CA1) and ipsilateral dentate gyrus (DG) compared to placebo-treated animals in EE. In conclusion, we present evidence for the association between polymorphic variants in the ESR1 and TNFRS11B genes and ICH and show that 17β-estradiol in combination with EE accelerates cognitive functions in a rat stroke model, putatively through upregulation of NGFI-A in hippocampal subregions. These findings may contribute to an increased understanding of the underlying genetic etiology of ICH and may be informative for the primary prevention of this disease. They also provide hope for 17β-estradiol combined with early environmental enrichment as a novel therapeutic option following ischemic stroke.

Ovarian cancer is thought to be derived from the ovarian surface epithelium (OSE), but it is often diagnosed during the late stages and therefore the events that contribute to the initiation and progression of ovarian cancer are poorly defined. Epidemiological studies have indicated an association between the female reproductive hormones and ovarian cancer etiology, but the direct effects of 17β-estradiol (E2), progesterone (P4), luteinizing hormone (LH) and follicle stimulating hormone (FSH) on disease pathophysiology are not well understood. A novel transgenic mouse model of ovarian cancer was generated that utilized the Cre/loxP system to inducibly express the oncogene SV40 large and small T-Antigen in the OSE. The tgCAG-LS-TAg mice developed poorly differentiated ovarian tumours with metastasis and ascites throughout the peritoneal space. Although P4 had no effect; E2 significantly accelerated disease progression in tgCAG-LS-TAg mice. The early onset of ovarian cancer was likely mediated by E2’s ability to increase the areas of putative preneoplastic lesions in the OSE. E2 also significantly decreased survival time in ovarian cancer cell xenografts. Microarray analysis of the tumours revealed that E2 mainly affects genes involved in angiogenesis and cellular differentiation, proliferation, and migration. These results suggest that E2 acts on the tumour microenvironment in addition to its direct effects on OSE and ovarian cancer cells. In order to examine the role of the gonadotropins in ovarian cancer progression, the tgCAG-LS-TAg mice were treated with 4-vinylcyclohexene-diepoxide (VCD) to induce menopause. Menopause slowed the progression of ovarian cancer due to a change in the histological subtype from poorly differentiated tumours to Sertoli tumours. Using a transgenic mouse model, it was shown that E2 accelerated ovarian cancer progression, while P4 had little effect on the disease. Menopause (elevated levels of LH and FSH) altered the histological subtype of the ovarian tumours in the tgCAG-LS-TAg mouse model. These results emphasize the importance of generating animal models to accurately recapitulate human disease and utilizing these models to develop novel prevention and treatment strategies for women with ovarian cancer.

Ovarian cancer is thought to be derived from the ovarian surface epithelium (OSE), but it is often diagnosed during the late stages and therefore the events that contribute to the initiation and progression of ovarian cancer are poorly defined. Epidemiological studies have indicated an association between the female reproductive hormones and ovarian cancer etiology, but the direct effects of 17β-estradiol (E2), progesterone (P4), luteinizing hormone (LH) and follicle stimulating hormone (FSH) on disease pathophysiology are not well understood. A novel transgenic mouse model of ovarian cancer was generated that utilized the Cre/loxP system to inducibly express the oncogene SV40 large and small T-Antigen in the OSE. The tgCAG-LS-TAg mice developed poorly differentiated ovarian tumours with metastasis and ascites throughout the peritoneal space. Although P4 had no effect; E2 significantly accelerated disease progression in tgCAG-LS-TAg mice. The early onset of ovarian cancer was likely mediated by E2’s ability to increase the areas of putative preneoplastic lesions in the OSE. E2 also significantly decreased survival time in ovarian cancer cell xenografts. Microarray analysis of the tumours revealed that E2 mainly affects genes involved in angiogenesis and cellular differentiation, proliferation, and migration. These results suggest that E2 acts on the tumour microenvironment in addition to its direct effects on OSE and ovarian cancer cells. In order to examine the role of the gonadotropins in ovarian cancer progression, the tgCAG-LS-TAg mice were treated with 4-vinylcyclohexene-diepoxide (VCD) to induce menopause. Menopause slowed the progression of ovarian cancer due to a change in the histological subtype from poorly differentiated tumours to Sertoli tumours. Using a transgenic mouse model, it was shown that E2 accelerated ovarian cancer progression, while P4 had little effect on the disease. Menopause (elevated levels of LH and FSH) altered the histological subtype of the ovarian tumours in the tgCAG-LS-TAg mouse model. These results emphasize the importance of generating animal models to accurately recapitulate human disease and utilizing these models to develop novel prevention and treatment strategies for women with ovarian cancer.

>Magister Scientiae - MSc / Current water treatment technologies do not remove many endocrine disruptor compounds (EDCs) such as 17α-ethynylestradiol (EE2) in its entirety, and the amount of these pollutants that continues to enter the aquatic environment through wastewater effluents is still capable of causing harmful health effects. Therefore the development of simpler and more sensitive biosensor system for detection of EE2 must be developed which have high responsiveness, low cost and easy handling. Therefore the aim of this study was to work towards the development of rapid test system of polyaniline-laccase on gold enzyme nanobiosensor (PANI-PSSA/Lac/Glu) for water estrogens. Preliminary studies were first done on the materials used in this study: estrogens, laccase, gold nanoparticles (AuNPs), and electropolymerized PANI-PSSA. Laccase was shown to be active towards EE2 and the enzyme could be stored for over three months. EE2 solution also could be used for over three months. Buffer used in this study was found to be suitable. Phosphoric acid (H3PO4) was a suitable electrolyte than hydrochloric acid (HCl) to be used for the electropolymerization of aniline and was used because it has same ions as the McIlvaine buffer (McIlB) which the post-deposition CVs indicated the formation of electrochemically very stable film. AuNPs were successfully synthesized and its size was identified to be less than 22 nm. McIlB used for testing electrochemical properties of AuNP. CVs of GC/PANI-PSSA and GC/PANIPSSA/ Au showed no difference before and after exposure to aq. EE2 solution, an indication of being re-usable and could also serve as stable immobilising platform in laccase biosensor. When interrogating with electrochemical impedance spectroscopy (EIS), the charge transfer resistance (Rct) of both GC/PANI-PSSA and GC/PANI-PSSA/Lac/Glu showed an average increase by about 2.4% and 21% before and after exposure of EE2, respectively. This shows that the GC/PANI-PSSA/Lac/Glu was a functional EE2 biosensor and showing a positive step towards achieving a re-usable biosensor for EE2 as a model water estrogen. Future work Page | vi will focus on exploring different ways of improving the biosensor’s surface regeneration and its sensitivity to EE2.

Many exogenous and endogenous compounds are referred to as endocrine disruptors (EDCs), as they interfere with natural synthesis, signaling and metabolism of endogenous hormones. Common exogenous endocrine disruptors are benzo(a)pyrene (BaP) and 17α-ethinylestradiol (EE2). Endogenous endocrine disruptor 17β-estradiol (E2) is frequently present in the environment as well. In this thesis, the effect of the mentioned EDCs and their combinations on gene and protein expression of CYP1B1, 3A1 and 3A2 in rat liver, kidney and lung was determined. Protein expression was studied using Western blot method and specific antibodies; gene expression was assessed by quantitative PCR. Moreover, the effect of tested EDCs and their combinations on BaP metabolism and CYP3A specific activity (measured as testosterone 6β-hydroxylation) were studied in liver microsomal samples. It was confirmed, that BaP significantly increases CYP1B1 expression in rat liver and lung both alone and together with EE2 or E2. Pretreatment of rat with E2 and BaP increases the ability of BaP to induce CYP1B1 expression. On the contrary, EE2, E2 and their combination decrease the CYP1B1gene expression. The rate of BaP metabolites formed in liver microsomal samples increases in rats pretreated with BaP and its combinations. In liver, there was...

Ovarian cancer is thought to be derived from the ovarian surface epithelium (OSE), but it is often diagnosed during the late stages and therefore the events that contribute to the initiation and progression of ovarian cancer are poorly defined. Epidemiological studies have indicated an association between the female reproductive hormones and ovarian cancer etiology, but the direct effects of 17β-estradiol (E2), progesterone (P4), luteinizing hormone (LH) and follicle stimulating hormone (FSH) on disease pathophysiology are not well understood. A novel transgenic mouse model of ovarian cancer was generated that utilized the Cre/loxP system to inducibly express the oncogene SV40 large and small T-Antigen in the OSE. The tgCAG-LS-TAg mice developed poorly differentiated ovarian tumours with metastasis and ascites throughout the peritoneal space. Although P4 had no effect; E2 significantly accelerated disease progression in tgCAG-LS-TAg mice. The early onset of ovarian cancer was likely mediated by E2’s ability to increase the areas of putative preneoplastic lesions in the OSE. E2 also significantly decreased survival time in ovarian cancer cell xenografts. Microarray analysis of the tumours revealed that E2 mainly affects genes involved in angiogenesis and cellular differentiation, proliferation, and migration. These results suggest that E2 acts on the tumour microenvironment in addition to its direct effects on OSE and ovarian cancer cells. In order to examine the role of the gonadotropins in ovarian cancer progression, the tgCAG-LS-TAg mice were treated with 4-vinylcyclohexene-diepoxide (VCD) to induce menopause. Menopause slowed the progression of ovarian cancer due to a change in the histological subtype from poorly differentiated tumours to Sertoli tumours. Using a transgenic mouse model, it was shown that E2 accelerated ovarian cancer progression, while P4 had little effect on the disease. Menopause (elevated levels of LH and FSH) altered the histological subtype of the ovarian tumours in the tgCAG-LS-TAg mouse model. These results emphasize the importance of generating animal models to accurately recapitulate human disease and utilizing these models to develop novel prevention and treatment strategies for women with ovarian cancer.

<p> The age at which a juvenile female reaches sexual maturity can be modulated by a variety of environmental and social factors. Experiments described in this thesis were designed to enhance the current understanding of the relationships among three variables that influence the onset of sexual maturation in female mice (Mus musculus), including: [1] exposure to dietary phytoestrogens during development, [2] variations in prenatal androgens, and [3] the presence or absence of genetically-unrelated males after weaning. For the first time, age at onset of male-induced female puberty was investigated using non-invasive behavioural and fertility measures. Through enzyme immunoassay procedures, daily output of urinary creatinine, 17P-estradiol, and progesterone was profiled in developing females that were either isolated or exposed to adult males. Uterine and ovarian tissue was also measured in such females, and male exposure was observed to increase reproductive tissue mass and was influenced by prior androgen exposure in interaction with diet and male presence. Male-exposed females fed a diet containing phytoestrogens immediately became sexually receptive when housed directly with males, and they conceived earlier than females in other conditions. Females with longer anogenital distance, which reflects higher in utero androgen exposure, displayed more escape attempts and aggressive posturing in the direct presence of males, especially when they had been housed near males and fed the phytoestrogen-containing diet. Urinary 17P-estradiol was substantially reduced in females raised on the phytoestrogenfree diet. Urinary output of progesterone was not strongly influenced by diet. Maleexposed females ' output of progesterone and 17P-estradiol was more dynamic in comparison to that of isolated females. The size of this effect depended on diet, prior androgen exposure, and whether urinary steroid measures were adjusted by urinary creatinine. Urinary creatinine was elevated by the low phytoestrogen diet and reduced by male exposure. These data suggest that dietary phytoestrogens and in utero androgen exposure interact with presence or absence of males in determining the age at onset of sexual maturity in developing females. </p> <p> A final experiment was designed to examine two components of adult male urine, preputial gland emissions and unconjugated estrogens, that have been posited to act on females to advance reproductive maturation. Intact and preputialectomized males were compared in their output of urinary creatinine, 17~-estradiol, and testosterone, and in their influence on reproductive tissue in juvenile females. Lack of preputial glands did not hinder the capacity of males to induce uterine and ovarian growth in females. Male urinary creatinine was reduced by exposure to juvenile females. Creatinine-adjusted 17~estradiol and testosterone were greater in female-exposed males, regardless of whether the preputial glands were present. Based on these findings and those reported elsewhere, it is probable that male excreted urinary steroids are important in regulating reproductive changes in developing females exposed to males. </p> / Thesis / Doctor of Philosophy (PhD)

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.

No description available.