Alzheimer’s disease is an insidious neurodegenerative disease that affects millions of people worldwide. Currently, there are no determinants that can accurately predict the onset cognitive decline in AD. This thesis investigates and defines changes in the lipidome that are linked to symptomatic onset and cognitive impairment in mouse models of AD. Using a targeted lipidomic approach employing high performance liquid chromatography electrospray ionization tandom mass spectrometry, direct biochemical assessments, and behavioural evaluation, I was able to (a) profile and quantify cortical and hippocampal glycerophosphocholine and glycerophosphoethanolamine metabolites and signaling molecules in the APPSwe/PS1dE9 and the N5 TgCRND8 murine models of AD and (b) associate changes in lipid metabolism with learning and memory impairment. I demonstrate that glycerophosphocholine metabolism in the cortex but not the hippocampus is altered at symptomatic onset in both mouse models. These same metabolic changes were seen in younger animals exposed to chronic intermittent hypoxia, an environmental risk factor that accelerates their phenoconversion. In fully impaired transgenic mice, I defined metabolic changes associated with disease progression. To further assess the impact of sex, another risk factor of Alzheimer’s disease cognitive decline, I characterized an AD model of sex-specific cognitive resistance. I demonstrated that transgenic males but not females exhibit behavioural indices of cognitive reserve when tested in the Morris Water Maze. Using this mouse line, I then investigated how measures of learning and memory associated with glycerophosphocholine and glycerophosphoethanolamine metabolism. I identified increases in critical glycerophosphoethanolamine metabolites linked to spatial learning and memory impairment in the cortex of N5 TgCNRD8 mice and demonstrated that these changes could be predicted by profiling the plasma glycerophosphoethanolamine lipidome. Taken together, this thesis links glycerophospholipid metabolism to the onset and progression of learning and memory impairment in experimental models of AD and provides the first evidence that changes in cortical lipid metabolism can be predicted by changes in the plasma lipidome.

Alzheimer's Disease and Related Disorders (ADRD) are a major public health problems. Major sources of care provision are family members in the community and these ADRD caregivers encounter a variety of stressor. Currently there continues to be a need to develop and test Internet based interventions designed to reduce stress for caregivers for persons with ADRD. The web-based Structured Written Emotional Expressions (SWEE) was developed to manage ADRD caregivers stress related to caregiving experiences through writing about their thoughts and feelings. However, differences between provided services by researchers (the web-based SWEE) and the desired services of ADRD caregivers could be a barrier to ADRD caregivers' acceptance and use of the web-based SWEE. The purpose of this study was to assess the acceptability of implementing a web-based nursing intervention for ADRD caregivers and to describe participants' experiences in using the website to understand ADRD caregivers' website usage. An experimental design was used to determine whether the web-based SWEE helped to manage ADRD caregivers' stress through writing interventions. In addition, the UTAUT model was employed for a theoretical framework to explain and predict the web-based SWEE usage behavior by ADRD caregivers. The Finding Meaning Through Caregiving Scale (FMTCS) was used to evaluate finding-meaning related to caregiving experiences as a mediator between performance expectancy and behavioral intention to use in the UTAUT model. Furthermore, the web-based research methods were assessed throughout the web-based SWEE implementing process. Both web-based and paper-based methods were used for recruiting potential participants. Most people who contacted the researcher were recruited by the web-based method. Structural Equation Modeling (SEM) was used for test ADRD caregivers' acceptability of the web-based SWEE and direct content analysis was used for describing participants' experiences in using the web-based SWEE. Fifty people completed the study out of the 90 people who enrolled. Of these 50 participants, 31 completed the study as intended and on schedule. The research showed a good model fit with a Chi-square value (df=43) of 57.191 (p>0.05). The findings showed that performance expectancy had a significant effect on participants' behavioral intention to use (β=0.620, p<0.01) and that effort expectancy also affected the behavioral intention to use the web-based SWEE (β=0.293, p<0.01). Performance expectancy showed stronger effects than effort expectancy. This model explained 52% of variance in behavioral intention to use. However, the effects of facilitating conditions on actual usage and effects of behavioral intention to use on actual usage were not supported by this research. The finding-meaning measure did not show a significant mediating effect on the relationship between performance expectancy and behavioral intention to use. Findings suggested that recruitment methods which use the Internet were an effective way to find potential study participants. Regardless of the topic, the writing intervention helped ADRD caregivers to express stress related to caregiving experiences. In addition, the perceived usefulness of this nursing intervention (performance expectancy) and the perceived ease of use (effort expectancy) were two important constructs which predicted and explained the acceptance of the web-based SWEE by ADRD caregivers. Finally, even though the UATAUT model was only partially supported by a good model fit, this study's findings showed the potential of the UTAUT model for providing health consumer information systems in nursing.

Alzheimer’s Disease (AD) is the only condition in the top ten leading causes of death for which we do not have an effective treatment that prevents, slows, or stops its progression. Our ability to design useful interventions relies on (a) increasing our understanding of the pathological process of AD and (b) improving our ability for its early detection. These goals are impeded by our current reliance on the clinical symptoms of AD for its diagnosis. This characterizations of AD often falsely assumes a unified, underlying AD-specific pathology for similar presentations of dementia that leads to inconsistent diagnoses. It also hinges on postmortem verification, and so is not a helpful method for identifying patients and research subjects in the beginning phases of the pathophysiological process. Instead, a new biomarker-based approach provides a more biological understanding of the disease and can detect pathological changes up to 20 years before the clinical symptoms emerge. Subjects are assigned a profile according to their biomarker measures of amyloidosis (A), tauopathy (T) and neurodegeneration (N) that reflects their underlying pathology in vivo. AD is confirmed as the underlying pathology when subjects have abnormal values of both amyloid and tauopathy biomarkers, and so have a biomarker profile of A+T+(N)- or A+T+(N)+. This new biomarker based characterization of AD can be combined with machine learning techniques in multimodal classification studies to shed light on the elements of the AD pathological process and develop early detection paradigms. A guiding research framework is proposed for the development of reliable, biologically-valid and interpretable multimodal classification models.

Alzheimer's disease (AD) is the most common neurodegenerative disease, characterized by progressive amyloid plaque aggregation, neurofibrillary tangles, and cortical tissue death. As the prevalence of AD is projected to climb in coming years, there is a vested interest in identifying endophenotypes by which to improve diagnostics and direct clinical interventions. The risk for complex disorders, such as AD, is influenced by multiple genetic, environmental, and lifestyle factors. Significant strides have been made in identifying genetic variants linked to AD through the genome-wide association study (GWAS). It has been estimated in more recent years, however, that GWAS-identified variants account for limited AD heritability, suggesting the role of non-sequence genetic mechanisms, such as epigenetic moderators. By influencing gene expression, epigenetic markers have been linked to age- associated decline through modulation of chromatin architecture and global genome instability, though such mechanisms are also involved with a number of normal biological processes, including neurogenesis. As the strategies of clinical genetics shift to include a heavier focus on epigenetic contributors, altered adult neurogenesis presents itself as a strong candidate for an endophenotype of AD development. This thesis proposes that, due to neuropathological dysfunction of epigenetic mechanisms in AD, new generations of neurons fail to proliferate, differentiate, and mature correctly, resulting in the larger loss of neurons and cognitive deficits characteristic to neurodegenerative disease. The plasticity of the epigenome and the role of epigenetic factors as mediators of the genome and the environment make such alterations attractive in AD research and implies the potential for therapeutic interventions. The present review submits neurogenesis as a viable target of epigenetic research in AD, highlights shared loci between neurogenesis and AD in the epigenome, and considers the promises and limitations of the neurogenic endophenotype.

Tauopathies are a group of neurodegenerative diseases characterized by the abnormal deposition of the protein tau, a microtubule stabilizing protein. Under normal physiological conditions tau is a highly soluble protein that is not prone to aggregation. In disease states alterations to tau lead to enhanced fibril formation and aggregation, eventually forming neurofibrillary tangles (NFTs). The exact cause for NFT deposition is unknown, but increased post-translational modifications and mutations to the tau gene can increase tangle formation. Tauopathic brains are stuck in a detrimental cycle, with cellular dysfunction contributing to the development of tau pathology and the development of tau pathology contributing to cellular dysfunction. The exact mechanisms by which each part of the cycle contributes to the other are still being explored. To investigate the unique contributions of each part of this cycle we utilized two separate models of tauopathy: one chronic and one acute. Overall this project provides novel insight into the role of pathological tau as both a cause, and a consequence, of cellular dysfunction. To understand how development of tau pathology contributes to cellular dysfunction we studied chronic disease models. Using human brain tissue we found that under normal conditions tau associates with ribosomes but that this interaction is enhanced in Alzheimer’s disease brains. We then used in vitro and in vivo models of tauopathy to show that this association causes a decrease in protein synthesis. Finally, we show that wild type tau and mutant tau reduce protein translation to similar levels. To understand how general cellular dysfunction contributes to development of pathology we used an acute model of tauopathy through traumatic brain injury (TBI). We injured rTg4510 tau transgenic mice at different ages to investigate the effect of TBI on tau fibrillization (2 month old) and the effect of TBI on tau already in NFTs (4.5 month old). In 2 month old mice, we found that tau hyperphosphorylation was decreased at 24 hours and increased at 7 days post injury, and that tau oligomerization was decreased at 24 hours post injury. We also found that tau fibrillization was not increased after 24 hours or 7 days post injury. In 4.5 month old mice, we found that TBI did not increase or decrease tangle counts in the brain, but we did qualitatively observe decreased variability within groups. Overall these studies contribute novel understanding of tau’s role in different disease states. We identified a functional consequence of the interaction between tau and ribosomes, and demonstrated that a single head impact did not increase tau fibril formation within 7 days of injury. While human diseases associated with TBI show neurofibrillary tangle deposition, we have yet to recreate that aspect of the disease in research models of TBI. Our findings support the need for further investigation into the nuances of tau in disease, especially following TBI.

Alzheimer's disease, the most common form of dementia, is estimated to occur in up to sixteen percent of people between the ages of 75 and 84. Deficits in linguistic skills that effect communication are a hallmark of the disease and have been the primary focus of past Alzheimer's research. Among other deficits, researchers have found that people with Alzheimer's often use indexical expressions without clear referents and convey less information that is relevant to the task they have been asked to perform than healthy subjects. Relatively little research has examined how Alzheimer's subjects use their linguistic knowledge to communicate with others in natural, open-ended interaction. The purpose of the present study was to identify what communication skills remain intact that enable an Alzheimer's subject to maintain conversational fluency despite lexical and pragmatic deficits. The study focused specifically on language skills that play a functional role in facilitating conversation. The data used in this study consisted of eight naturally occurring conversations between the subject and three interlocutors who had a close relationship with the subject. The interactions were recorded in the Alzheimer's wing of the subject's nursing home. The transcribed conversations were analyzed according to three types of functional language drawn from Nattinger and DeCarrico's (1992) work on lexical phrases: (1) conversational maintenance; (2) conversational purpose; and (3) familiar topics. The role played by lexical phrases in facilitating each of these functional categories was also examined. This study found that the subject had an intact knowledge of functional language skills that allowed her to successfully participate in conversation despite serious language deficits. Within the category of conversational maintenance, the subject retained skills necessary to share control in opening and closing conversations as well as nominating and shifting topics and requesting and offering clarification. In the category of conversational purpose, the subject used functional language to signal utterances intended to convey general politeness, gratitude and compliments as well as informing the interlocutor of her attitude in relation to the content of utterances. The study also found that lexical phrases played a central role in facilitating the subject's use of functional language.

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Aneta Ritomská Supervisor: Assoc. Prof. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Derivatives of Amaryllidaceae Alkaloids as Drugs Plants of the family Amaryllidaceae belong to the widespread species. They contain a large amount of Amaryllidaceae alkaloids (AA) which are known for their biological activity. AA possess a broad spectrum of biological activities including an antiviral, antimalarial, antitumor, cholinesterase's inhibitory activity and others. An interesting AA is ambelline which occurs mainly in plants of the genus Crinum and Nerine. So far the biological activity of this compound has been studied only marginally. In the studies conducted, this substance appears to be less interesting. A series of aliphatic and aromatic derivatives of ambelline has been prepared in the framework of this thesis. Subsequently, their cholinesterase inhibitory activity and GSK-3β inhibitory activity were studied. Cytotoxic activity on a panel of selected tumor and resting cell lines was also screened. Of the prepared derivatives, LC-125 (3-methoxybenzoylambellin) had an interesting biological activity. This substance showed a promising activity in all biological studies. GSK-3β inhibitory...

The level of burden experienced by caregivers of patients diagnosed with Alzheimer's disease is high. Studies that examine this burden by taking into account cultural and spiritual differences are limited, particularly with regard to minority populations. The purpose of this study was to investigate the burden and challenges faced by minority caregivers providing in-home care to Alzheimer's patients. Guided by social support theory, a phenomenological study design was used with semi-structured interviews of 12 caregivers to examine their perspectives on the burden and challenges they face, including their lived experiences, cultural and spiritual values, and interaction with health professionals. Thematic analysis in an inductive way was used to analyze the collected qualitative data. The results of the analyses of the collected data showed that cultural and spiritual values are important in making decisions, as caregivers in minority populations face daily challenges in terms of limited social support and resources. The findings of this study suggest that public health interventions aimed at alleviating the burden on Alzheimer's caregivers need to take into account differences in cultural and spiritual values. Findings also show that there is a need for social support programs that reduce the burden on caregivers in general and on the minority population in particular. The findings of this study may drive positive social change by helping public health workers design and implement programs that consider differences in the cultural and spiritual values of minority populations while garnering the resources to provide the needed social support and alleviate the burden faced by the family member caregivers.

Alzheimer's disease (AD) is a significant public health concern for all elders in the United States. It is a particular concern for the American Indian (AI) population, which is one of the fastest-aging populations in the United States and the smallest, most underrecognized, and most culturally-diverse group in the country. A formal caregiver understanding of AD in the AI population is scarce. This phenomenological study was designed to discern what is known about AD in the AI population by exploring the cultural beliefs and experiences of formal caregivers who provide care for AI dementia patients. Specifically, this study sought to document formal caregiver and AI dementia beliefs about AD. Data came from 4 in-depth interviews that included 3 Western and one AI formal caregiver. These interviews explored the variability of cultural beliefs regarding AD and dementia among a sample of formal caregivers who minister to AI patients; in the interviews, these participants also provided examples of challenges they faced, providing a better cultural understanding of AI dementia. Results suggested that challenges include adopting a bicultural approach to AD, illuminating interactions between patient and provider, and fostering awareness of cultural competency. Research on this topic is critical in advancing cultural, public health, and evidence-based health practices regarding AI dementia patients. The potential implications for social change include enhancing cross cultural provider-patient interactions and advancing public health policy and practice for this underserved population. Many of the issues and challenges explored may have implications for other ethnocultural minority groups.

The microtubule-associated protein tau is known for its ability to bind to and stabilize microtubules and for its ability to nucleate microtubule assembly. In neurodegenerative tauopathies such as Alzheimer's disease, tau becomes hyperphosphorylated and loses the capacity for microtubule binding, possibly contributing to microtubule destabilization and axonal degeneration. However, evidence now indicates that soluble forms of hyperphosphorylated tau might have a toxic gain of function linked to abnormal signal transduction and cell cycle events in normally post-mitotic neurons. In support of this hypothesis, tau has been found to associate with numerous signaling proteins such as tyrosine kinases, adaptor proteins, and scaffold proteins. During early brain development, fetal tau is also more phosphorylated than tau in the adult brain and weakly binds microtubules, suggesting tau has functions in addition to microtubule stabilization. The aim of this dissertation research is to investigate the possible role of tau in neuronal signaling, using tau-expressing and tau-depleted cell lines. Here, we provide evidence that during growth factor stimulation of neuronal cells, tau functions in advance of the neurite elongation stage. Tau is required for neurite initiation in a manner that does not require its microtubule binding function, and in addition, tau potentiates AP-1 transcription factor activation in response to nerve growth factor (NGF). The effect of tau on AP-1 activation is mediated through the enhanced activation of extracellular signal-regulated kinase (ERK), in response to both NGF and epidermal growth factor (EGF). We show that phosphorylation of tau at Thr231 also occurs in response to NGF and is required for tau to impact on ERK signaling, whereas the ability of tau to bind to microtubules is not required. Together, these findings indicate a new functional role for tau in neuronal signal transduction and have implications for tau function during early brain development and in neurodegenerative disease.