Pituitary adenylate cyclase activating polypeptide (PACAP) is associated with Alzheimer's disease (AD), but its age-related effects are unknown. We chose the rhesus macaque due to its closeness to human anatomy and physiology. We examined four variables: aging, cognitive performance, amyloid plaques and PACAP. Delayed nonmatching-to-sample recognition memory scores declined with age and correlated with PACAP levels in the striatum, parietal and temporal lobes. Because amyloid plaques were the only AD pathology in the old rhesus macaque, we further studied human amyloid precursor protein (hAPP) transgenic mice. Aging was associated with decreased performance in the Morris Water Maze (MWM). In wild type (WT) C57BL/ 6 mice, the performance was decreased at age 24-26 month whereas in hAPP transgenic mice, it was decreased as early as 9-12 month. Neuritic plaques in adult hAPP mice clustered in hippocampus and adjacent cortical regions, but did not propagate further into the frontal cortex. Cerebral PACAP protein levels were reduced in hAPP mice compared to age-matched WT mice, but the genetic predisposition dominated cognitive decline. Taken together, these data suggest an association among PACAP levels, aging, cognitive function and amyloid load in nonhuman primates, with both similarities and differences from human AD brains. Our results suggest caution in choosing animal models and in extrapolating data to human AD studies.

KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in

Neuroinflammation occurs in Alzheimer’s disease (AD) brain, and plays a role in neurodegeneration. The main aim of this study was to determine how treatments with exogenous apolipoprotein E (ApoE2, E3 and E4 isoforms), a genetic risk factor for AD, affects the amyloid-β (Aβ) induced inflammatory response in vitro in astrocytes. Recombinant, lipid-free ApoE4 was found not to affect Aβ-induced inflammation in rat astrocytes, while ApoE2 showed a protective effect. Mouse cells expressing human ApoE isoforms, which have similar lipidation and modification to native human ApoE, showed ApoE4 promoting inflammation, and no ApoE2 protective effect upon Aβ treatment. A Protein/DNA array was used to screen 345 transcription factors in rat astrocytes treated with Aβ and/or ApoE isoforms, in order to determine which contribute to the observed ApoE2 protection. Some candidates were validated by Western Blot or EMSA and/or by inhibition or activation. The findings suggest ApoE isoforms differentially regulate Aβ-induced inflammation, and multiple signalling pathways are involved in the process.

Ageing is a process correlated with cellular stress and increased risks of neurodegenerative diseases, in particular Alzheimer’s disease (AD), which is accompanied with severe cognitive and memory impairments. Both ageing and AD affect many brain regions and thus induce brain malfunctions. Among the brain regions, the entorhinal cortex (EC) has drawn more and more attentions due to its pivotal role in cognition and memory functions as well as its vulnerability to ageing process and AD neuropathology. Synaptic and neuronal degenerations, which are also manifest features of AD, occur in the EC during the ageing process and at the early stage of AD. In addition, both pathological hallmarks of AD, namely abnormal accumulation of β-amyloid (Aβ) and hyperphosphorlation of tau proteins, initially appear in the EC and then progress to other brain regions such as the hippocampus and the neocortex. Glial alterations in AD and ageing process have been considered as secondary event to neuronal changes. Nevertheless, accumulating evidence indicates the relevant and primary involvement of astroglia, which is responsible for brain homeostasis, in AD and ageing. In this thesis, we have focused on the astroglial alterations in the EC during the progression of AD in an animal model of the disease as well as in ageing process in non-transgenic control mice. We have used the triple transgenic mouse model of AD (3xTg-AD), which is the most relevant animal model of AD and resembles the spatiotemporal progression of human AD pathology. Our results revealed cytoskeletal atrophy of astrocytes in the EC of 3xTg-AD animals (Chapter 3), shown by significant decrease in GFAP surface and volume. This astroglial alteration began at very early age (1 month) and sustained till more advanced age (12 month). Moreover, Aβ plaques did not trigger astrogliosis, and there was rare presence of GFAP labelled astrocytes in the vicinity of Aβ deposition. This may reflect the relative indifference of astroglia in the EC and thus explain the susceptibility of the EC at the early stage of AD. To study whether astroglial atrophy in cytoskeleton compromise astrocytic function in glutamate homeostasis, we investigated the expression of glutamine synthetase (GS), which is specifically expressed in astrocytes and is critical for glutamate balance (Chapter 4). Our results showed constant GS expression and the density of GS positive astrocytes in the EC. However, dual labelling of GS and GFAP revealed 3 different subsets of astrocytes, being GS-, GFAP-, GS/GFAP- positive astrocytes. The morphology of GS-IR cells, measured by surface and volume, did not change in spite of the evident GFAP atrophy. Therefore, GFAP atrophy does not disturb glutamate homeostasis in the EC, suggesting diverse functional populations of astrocytes, which may show distinct responses during AD progression. In addition we also analysed astroglial changes during the ageing process in the EC and its major projection area, the hippocampus (Chapter 5). Astrocytes in the hippocampus exhibited prominent hypertrophy, shown by increased GFAP whereas entorhinal astrocytes in the EC had profound reduction in GFAP expression. This may implicate heterogeneous astrocytic responses to ageing in different brain regions. The general atrophy of astrocytes in the EC of 3xTg-AD mice and aged controls, suggests astroglial atrophy may results in reduced astrocytic coverage and modulation of synapses, accounting for the synaptic dysfunction in ageing and AD.

A report from the National Institutes of Health defines a disease biomarker as a "characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention." Early diagnosis is a crucial factor for incurable disease such as cancer and Alzheimer’s disease (AD). During the last decade researchers have discovered that biochemical changes caused by a disease can be detected considerably earlier as compared to physical manifestations/symptoms. In this dissertation electrochemical detection was utilized as the detection strategy as it offers high sensitivity/specificity, ease of operation, and capability of miniaturization and multiplexed detection. Electrochemical detection of biological analytes is an established field, and has matured at a rapid pace during the last 50 years and adapted itself to advances in micro/nanofabrication procedures. Carbon fiber microelectrodes were utilized as the platform sensor due to their high signal to noise ratio, ease and low-cost of fabrication, biocompatibility, and active carbon surface which allows conjugation with bio-recognition moieties. This dissertation specifically focuses on the detection of 3 extensively validated biomarkers for cancer and AD. Firstly, vascular endothelial growth factor (VEGF) a cancer biomarker was detected using a one-step, reagentless immunosensing strategy. The immunosensing strategy allowed a rapid and sensitive means of VEGF detection with a detection limit of about 38 pg/mL with a linear dynamic range of 0–100 pg/mL. Direct detection of AD-related biomarker amyloid beta (Aβ) was achieved by exploiting its inherent electroactivity. The quantification of the ratio of Aβ1-40/42 (or Aβ ratio) has been established as a reliable test to diagnose AD through human clinical trials. Triple barrel carbon fiber microelectrodes were used to simultaneously detect Aβ1-40 and Aβ1-42 in cerebrospinal fluid from rats within a detection range of 100nM to 1.2μM and 400nM to 1μM respectively. In addition, the release of DNA damage/repair biomarker 8-hydroxydeoxyguanine (8-OHdG) under the influence of reactive oxidative stress from single lung endothelial cell was monitored using an activated carbon fiber microelectrode. The sensor was used to test the influence of nicotine, which is one of the most biologically active chemicals present in cigarette smoke and smokeless tobacco.

The cellular prion protein (PrP) has been shown to act as a receptor for soluble oligomers of amyloid-beta (Aβ), an ~4 kDa amyloidogenic peptide that is found in neuritic plaques that are a pathological hallmark of Alzheimer’s disease (AD). Oligomeric forms of the Aβ peptide are thought to be synaptotoxic, and have been shown to produce PrP-dependent dendritic spine loss, suppression of long term potentiation (LTP), and behavioral changes in mouse models of AD. However, the specific molecular interactions between PrP and Aβ have not been fully characterized. In this work, we conducted a robust examination of the kinetic processes leading to Aβ fibril formation, and present evidence that PrP significantly inhibits Aβ polymerization. Using established mathematical models of polymerization kinetics, we show that inhibition is based on binding between PrP and the ends of Aβ filaments, an interaction that blocks elongation. To support these results, we conducted multiple binding assays to show that PrP binds to monomers of Aβ with low affinity, oligomers with intermediate affinity, and to fibrils with high affinity. These results extend upon previous studies, which have focused only on the interaction between oligomeric Aβ and PrP. To better understand the molecular interactions required for binding and inhibition of polymerization, we performed assays with a series of PrP deletion mutants, which revealed that low-affinity binding to Aβ monomer is dependent on the presence of the C-terminal domain of PrP. This domain is also required for Aβ polymerization inhibition. Based on our results, we propose a model in which the unstructured N-terminal domain of PrP binds to the ends of Aβ fibrils, while the C-terminal domain interrupts the docking of new monomers to fibril ends, in part through competing for similar binding sites. This study provides an important contribution to our understanding of the PrP-Aβ interaction that leads to synaptoxicity.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22689号 / 医博第4633号 / 新制||医||1045(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 林 康紀, 教授 伊佐 正, 教授 井上 治久 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Every 66 seconds, someone develops Alzheimer’s disease. Because of the baby boomer generation, this number will continue to rise significantly in the coming years (2016 Alzheimer’s Disease Facts and Figures). As a result, it is essential to consider memory impaired individuals when creating space; specifically, those spaces in which patients receive long term care. Though there are claims that a wide range of options exist for memory impaired assisted living, types of care can be easily sorted into three groups: home care, institution care, or for few select individuals, care in specialized communities known as dementia villages. While there is a spectrum of care for each of these categories, more often than not, the main stream option is a typical nursing home or assisted-living facility. The direct influence of traditional hospital typologies is evident in the layout of the building, and is in part due to the use of government funding (Day). Specialized dementia and Alzheimer’s care does exist in some cities, though generally memory units differ in patient demographic and programing, and not in the way that spaces are formed. The idea of a dementia village, an isolated community that encompasses all aspects of living and social life, has proved successful in increasing patient autonomy; however, such facilities often exist outside of the urban realm and are built on the foundation of imitation and replication. Through historical analysis of medical building typologies and formal investigation of spatial relationships, this thesis aims to explore the opportunities within built space that allow aging and memory-loss patients to feel comfort. By flipping the relationship between the private and public realms of the building, it is possible to generate increased social interaction, improving the overall quality of life of the patients. / 0 / SPK / specialcollections@tulane.edu

Alzheimer's disease (AD) is the most common cause of dementia initially characterised by short-term memory deficits followed by a progressive cross domain cognitive and functional decline over time and loss of independence in carrying out activities of daily living (ADL). Apathy and depression are also the two most frequent neuropsychiatric sequalae associated with AD and have an impact on patients' ability to execute ADLs. Little is still known if apathy subdomains differently predict ADL performance in these patients. In this study, we aimed to quantitatively investigate if global apathy and depression predict ADL performance. We also wanted to establish if the apathy evaluation scale (AES) items resolve into three factors as proposed by Marin and if those factors differently predict performance of ADLs. We recruited a sample of 115 patients diagnosed with probable or possible AD. Basing on current literature, we hypothesised that apathy and depression predict ADL performance. We also hypothesised that AES items will load into three factors relating to cognitive, behavioural and affective apathy subdomains and that these subdomains will differentially predict ADL performance in our patient sample. Our results indicated that high apathy and depression symptoms were associated with problems to carryout ADLs. They also indicated that AES items resolved into a three factor solution in analogy with Marin's conceptualisation but they did not cluster in the manner that he proposed. Finally, when these factors are regressed simultaneously, (derived from factor analysis) only behavioural apathy significantly predicted ADLs.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Chemistry and Drug Control Student: Pavla ábelová Supervisor: Assoc. Prof. RNDr. Veronika Opletalová, Ph.D. Supervisor specialist: PharmDr. Jan Korábe ný, Ph.D. Title of diploma thesis: Synthesis, biological evaluation and in silico studies in the series of novel 7-methoxytacrine-donepezile like compounds Alzheimer's disease (AD) is an irreversible neurodegenerative disorder of the brain characterized clinically by loss of memory, deterioration of activities of daily living and cognition. The pathological hallmarks of AD include neuritic plaques composed of extracellularly stored fibrils of amyloid- peptide, intracellular deposits of hyperphosphorylated tau and neurotransmitter deficits. The aim of the study was to design and synthesize 7-methoxytacrine-donepezil-like compounds as potential inhibitors of acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BChE, EC 3.1.1.8). New compounds consist of 7-methoxytacrine representing less toxic derivative of tacrine and benzylpiperazine moiety corresponding to donepezil fragment. To determine the potential of new derivatives, AChE and BChE inhibitory activities of the new molecules were assessed in vitro according to the method of Ellman et al....