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Sample records for alzheimer disease brains

  1. Brain histamine in Alzheimer's disease.

    PubMed

    Cacabelos, R; Yamatodani, A; Niigawa, H; Hariguchi, S; Tada, K; Nishimura, T; Wada, H; Brandeis, L; Pearson, J

    1989-05-01

    The concentration of histamine (HA) has been determined by high-performance liquid chromatography (HPLC) with fluorometric detection in 21 different regions of brains from patients with senile dementia of the Alzheimer type (SDAT) and subjects (CB) whose causes of death were not related to neuropsychiatric, neurological and/or neurodegenerative diseases. The highest levels of HA in the central nervous system (CNS) of both control (CB) and SDAT samples were found in the posterior hypothalamus (CB = 3.13 +/- 0.63 pmol/mg; SDAT = 7.75 +/- 1.43 pmol/mg, p less than 0.005), where the HA neurons are located, and in the anterior hypothalamus (CB = 1.77 +/- 0.33 pmol/mg; SDAT = 2.82 +/- 0.45 pmol/mg, p less than 0.005). The lowest HA levels were detected in the cerebellum (CB = 0.12 +/- 0.04 pmol/mg; SDAT = 0.24 +/- 0.09 pmol/mg, p less than 0.01) and medulla oblongata. HA levels were significantly higher in SDAT than in CB in the following areas: motor cortex (Brodmann's area 4) (A4), premotor cortex (A6), postcentral gyrus (A1,2), posterior parietal cortex (A5,7), superior temporal gyrus (A41,42), temporal pole (A38), primary and secondary visual cortices (A17,18), anterior and posterior regions of the hypothalamus, putamen, caudate nucleus, nucleus accumbens, thalamus, hippocampus, pons, medulla oblongata and cerebellum. No changes were seen in globus pallidus and corpus callosum. Since the origin of HA in the brain is dependent upon three main compartments (neuronal, mast cell, vascular smooth muscle), with approximately 60-80% of the total HA belonging to the neuronal pool, on the basis of neurochemical data we postulate that the increase in the levels of HA in SDAT might account for or be associated with alterations in neuroendocrine, cognitive, neurovascular and sleep-wakefulness functions. PMID:2755282

  2. Alzheimer disease

    MedlinePlus

    Senile dementia - Alzheimer type (SDAT); SDAT; Dementia - Alzheimer ... The exact cause of Alzheimer disease (AD) is not known. Research shows that certain changes in the brain lead to AD. You are more likely ...

  3. Metabolic profiling of Alzheimer's disease brains

    NASA Astrophysics Data System (ADS)

    Inoue, Koichi; Tsutsui, Haruhito; Akatsu, Hiroyasu; Hashizume, Yoshio; Matsukawa, Noriyuki; Yamamoto, Takayuki; Toyo'Oka, Toshimasa

    2013-08-01

    Alzheimer's disease (AD) is an irreversible, progressive brain disease and can be definitively diagnosed after death through an examination of senile plaques and neurofibrillary tangles in several brain regions. It is to be expected that changes in the concentration and/or localization of low-molecular-weight molecules are linked to the pathological changes that occur in AD, and determining their identity would provide valuable information regarding AD processes. Here, we propose definitive brain metabolic profiling using ultra-performance liquid chromatography coupled with electrospray time-of-flight mass spectrometry analysis. The acquired data were subjected to principal components analysis to differentiate the frontal and parietal lobes of the AD/Control groups. Significant differences in the levels of spermine and spermidine were identified using S-plot, mass spectra, databases and standards. Based on the investigation of the polyamine metabolite pathway, these data establish that the downstream metabolites of ornithine are increased, potentially implicating ornithine decarboxylase activity in AD pathology.

  4. Evidence for a membrane defect in Alzheimer disease brain

    NASA Technical Reports Server (NTRS)

    Nitsch, R. M.; Blusztajn, J. K.; Pittas, A. G.; Slack, B. E.; Growdon, J. H.; Wurtman, R. J.

    1992-01-01

    To determine whether neurodegeneration in Alzheimer disease brain is associated with degradation of structural cell membrane molecules, we measured tissue levels of the major membrane phospholipids and their metabolites in three cortical areas from postmortem brains of Alzheimer disease patients and matched controls. Among phospholipids, there was a significant (P less than 0.05) decrease in phosphatidylcholine and phosphatidylethanolamine. There were significant (P less than 0.05) decreases in the initial phospholipid precursors choline and ethanolamine and increases in the phospholipid deacylation product glycerophosphocholine. The ratios of glycerophosphocholine to choline and glycerophosphoethanolamine to ethanolamine were significantly increased in all examined Alzheimer disease brain regions. The activity of the glycerophosphocholine-degrading enzyme glycerophosphocholine choline-phosphodiesterase was normal in Alzheimer disease brain. There was a near stoichiometric relationship between the decrease in phospholipids and the increase of phospholipid catabolites. These data are consistent with increased membrane phospholipid degradation in Alzheimer disease brain. Similar phospholipid abnormalities were not detected in brains of patients with Huntington disease, Parkinson disease, or Down syndrome. We conclude that the phospholipid abnormalities described here are not an epiphenomenon of neurodegeneration and that they may be specific for the pathomechanism of Alzheimer disease.

  5. Brain injury, neuroinflammation and Alzheimer's disease

    PubMed Central

    Breunig, Joshua J.; Guillot-Sestier, Marie-Victoire; Town, Terrence

    2013-01-01

    With as many as 300,000 United States troops in Iraq and Afghanistan having suffered head injuries (Miller, 2012), traumatic brain injury (TBI) has garnered much recent attention. While the cause and severity of these injuries is variable, severe cases can lead to lifelong disability or even death. While aging is the greatest risk factor for Alzheimer's disease (AD), it is now becoming clear that a history of TBI predisposes the individual to AD later in life (Sivanandam and Thakur, 2012). In this review article, we begin by defining hallmark pathological features of AD and the various forms of TBI. Putative mechanisms underlying the risk relationship between these two neurological disorders are then critically considered. Such mechanisms include precipitation and ‘spreading’ of cerebral amyloid pathology and the role of neuroinflammation. The combined problems of TBI and AD represent significant burdens to public health. A thorough, mechanistic understanding of the precise relationship between TBI and AD is of utmost importance in order to illuminate new therapeutic targets. Mechanistic investigations and the development of preclinical therapeutics are reliant upon a clearer understanding of these human diseases and accurate modeling of pathological hallmarks in animal systems. PMID:23874297

  6. Early complement components in Alzheimer's disease brains.

    PubMed

    Veerhuis, R; Janssen, I; Hack, C E; Eikelenboom, P

    1996-01-01

    Activation products of the early complement components C1, C4 and C3 can be found colocalized with diffuse and fibrillar beta-amyloid (beta/A4) deposits in Alzheimer's disease (AD) brains. Immunohistochemically, C1-esterase inhibitor (C1-Inh) and the C1 subcomponents C1s and C1r can not, or only occasionally, be detected in plaques or in astrocytes. The present finding that C1q, C1s and C1-Inh mRNA are present in both AD and control brains suggests that the variable immunohistochemical staining results for C1r, C1s and C1-Inh are due to a rapid consumption, and that the inability to detect C1s, C1r or C1-Inh is probably due to the dissociation of C1s-C1-Inh and C1r-C1-Inh complexes from the activator-bound C1q into the fluid phase. Employing monoclonal antibodies specific for different forms of C1-Inh, no complexed C1-Inh could be found, whereas inactivated C1-Inh seems to be present in astrocytes surrounding beta/A4 plaques in AD brains. These findings, together with our finding (using reverse transcriptase-polymerase chain reaction) that C1-Inh is locally produced in the brain, suggest that in the brain complement activation at the C1 level is regulated by C1-Inh. Immunohistochemically, no evidence for the presence of the late complement components C5, C7 and C9, or of the membrane attack complex (MAC), was found in beta/A4 plaques. In contrast to the mRNA encoding the early components, that of the late complement components appears to be hardly detectable (C7) or absent (C9). Thus, without blood-brain-barrier impairment, the late complement components are probably present at too low a concentration to allow the formation of the MAC, which is generally believed to be responsible for at least some of the neurodegenerative effects observed in AD. Therefore, the present findings support the idea that in AD, complement does not function as an inflammatory mediator through MAC formation, but through the action of early component activation products.

  7. Brain aging, Alzheimer's disease, and mitochondria

    PubMed Central

    Swerdlow, Russell H.

    2011-01-01

    The relationship between brain aging and Alzheimer’s disease (AD) is contentious. One view holds AD results when brain aging surpasses a threshold. The other view postulates AD is not a consequence of brain aging. This review discusses this conundrum from the perspective of different investigative lines that have tried to address it, as well as from the perspective of the mitochondrion, an organelle that appears to play a role in both AD and brain aging. Specific issues addressed include the question of whether AD and brain aging should be conceptually lumped or split, the extent to which AD and brain aging potentially share common molecular mechanisms, whether beta amyloid should be primarily considered a marker of AD or simply brain aging, and the definition of AD itself. PMID:21920438

  8. The rationale for deep brain stimulation in Alzheimer's disease.

    PubMed

    Mirzadeh, Zaman; Bari, Ausaf; Lozano, Andres M

    2016-07-01

    Alzheimer's disease is a major worldwide health problem with no effective therapy. Deep brain stimulation (DBS) has emerged as a useful therapy for certain movement disorders and is increasingly being investigated for treatment of other neural circuit disorders. Here we review the rationale for investigating DBS as a therapy for Alzheimer's disease. Phase I clinical trials of DBS targeting memory circuits in Alzheimer's disease patients have shown promising results in clinical assessments of cognitive function, neurophysiological tests of cortical glucose metabolism, and neuroanatomical volumetric measurements showing reduced rates of atrophy. These findings have been supported by animal studies, where electrical stimulation of multiple nodes within the memory circuit have shown neuroplasticity through stimulation-enhanced hippocampal neurogenesis and improved performance in memory tasks. The precise mechanisms by which DBS may enhance memory and cognitive functions in Alzheimer's disease patients and the degree of its clinical efficacy continue to be examined in ongoing clinical trials.

  9. Apolipoprotein E receptors: linking brain development and Alzheimer's disease.

    PubMed

    Herz, J; Beffert, U

    2000-10-01

    Alzheimer's disease is a debilitating neurodegenerative disorder that afflicts an increasing part of our ageing population. An isoform of apolipoprotein E, a protein that mediates the transport of lipids and cholesterol in the circulatory system, predisposes carriers of this allele to the common late-onset form of the disease. How this protein is related to a neurodegenerative disorder is an enigma. Mounting evidence indicates that apolipoprotein E receptors, which are abundantly expressed in most neurons in the central nervous system, also fulfill critical functions during brain development and may profoundly influence the pathogenesis of Alzheimer's disease.

  10. Brain atrophy in Alzheimer's Disease and aging.

    PubMed

    Pini, Lorenzo; Pievani, Michela; Bocchetta, Martina; Altomare, Daniele; Bosco, Paolo; Cavedo, Enrica; Galluzzi, Samantha; Marizzoni, Moira; Frisoni, Giovanni B

    2016-09-01

    Thanks to its safety and accessibility, magnetic resonance imaging (MRI) is extensively used in clinical routine and research field, largely contributing to our understanding of the pathophysiology of neurodegenerative disorders such as Alzheimer's disease (AD). This review aims to provide a comprehensive overview of the main findings in AD and normal aging over the past twenty years, focusing on the patterns of gray and white matter changes assessed in vivo using MRI. Major progresses in the field concern the segmentation of the hippocampus with novel manual and automatic segmentation approaches, which might soon enable to assess also hippocampal subfields. Advancements in quantification of hippocampal volumetry might pave the way to its broader use as outcome marker in AD clinical trials. Patterns of cortical atrophy have been shown to accurately track disease progression and seem promising in distinguishing among AD subtypes. Disease progression has also been associated with changes in white matter tracts. Recent studies have investigated two areas often overlooked in AD, such as the striatum and basal forebrain, reporting significant atrophy, although the impact of these changes on cognition is still unclear. Future integration of different MRI modalities may further advance the field by providing more powerful biomarkers of disease onset and progression. PMID:26827786

  11. Brain atrophy in Alzheimer's Disease and aging.

    PubMed

    Pini, Lorenzo; Pievani, Michela; Bocchetta, Martina; Altomare, Daniele; Bosco, Paolo; Cavedo, Enrica; Galluzzi, Samantha; Marizzoni, Moira; Frisoni, Giovanni B

    2016-09-01

    Thanks to its safety and accessibility, magnetic resonance imaging (MRI) is extensively used in clinical routine and research field, largely contributing to our understanding of the pathophysiology of neurodegenerative disorders such as Alzheimer's disease (AD). This review aims to provide a comprehensive overview of the main findings in AD and normal aging over the past twenty years, focusing on the patterns of gray and white matter changes assessed in vivo using MRI. Major progresses in the field concern the segmentation of the hippocampus with novel manual and automatic segmentation approaches, which might soon enable to assess also hippocampal subfields. Advancements in quantification of hippocampal volumetry might pave the way to its broader use as outcome marker in AD clinical trials. Patterns of cortical atrophy have been shown to accurately track disease progression and seem promising in distinguishing among AD subtypes. Disease progression has also been associated with changes in white matter tracts. Recent studies have investigated two areas often overlooked in AD, such as the striatum and basal forebrain, reporting significant atrophy, although the impact of these changes on cognition is still unclear. Future integration of different MRI modalities may further advance the field by providing more powerful biomarkers of disease onset and progression.

  12. CARS microscopy of Alzheimer's diseased brain tissue

    NASA Astrophysics Data System (ADS)

    Enejder, Annika; Kiskis, Juris; Fink, Helen; Nyberg, Lena; Thyr, Jakob; Li, Jia-Yi

    2014-02-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder currently without cure, characterized by the presence of extracellular plaques surrounded by dystrophic neurites. In an effort to understand the underlying mechanisms, biochemical analysis (protein immunoblot) of plaque extracts reveals that they consist of amyloid-beta (Aβ) peptides assembled as oligomers, protofibrils and aggregates. Their spatial distribution has been confirmed by Thioflavin-S or immuno-staining with fluorescence microscopy. However, it is increasingly understood that the protein aggregation is only one of several mechanism that causes neuronal dysfunction and death. This raises the need for a more complete biochemical analysis. In this study, we have complemented 2-photon fluorescence microscopy of Thioflavin-S and Aβ immuno-stained human AD plaques with CARS microscopy. We show that the chemical build-up of AD plaques is more complex and that Aβ staining does not provide the complete picture of the spatial distribution or the molecular composition of AD plaques. CARS images provide important complementary information to that obtained by fluorescence microscopy, motivating a broader introduction of CARS microscopy in the AD research field.

  13. Lipidomics of human brain aging and Alzheimer's disease pathology.

    PubMed

    Naudí, Alba; Cabré, Rosanna; Jové, Mariona; Ayala, Victoria; Gonzalo, Hugo; Portero-Otín, Manuel; Ferrer, Isidre; Pamplona, Reinald

    2015-01-01

    Lipids stimulated and favored the evolution of the brain. Adult human brain contains a large amount of lipids, and the largest diversity of lipid classes and lipid molecular species. Lipidomics is defined as "the full characterization of lipid molecular species and of their biological roles with respect to expression of proteins involved in lipid metabolism and function, including gene regulation." Therefore, the study of brain lipidomics can help to unravel the diversity and to disclose the specificity of these lipid traits and its alterations in neural (neurons and glial) cells, groups of neural cells, brain, and fluids such as cerebrospinal fluid and plasma, thus helping to uncover potential biomarkers of human brain aging and Alzheimer disease. This review will discuss the lipid composition of the adult human brain. We first consider a brief approach to lipid definition, classification, and tools for analysis from the new point of view that has emerged with lipidomics, and then turn to the lipid profiles in human brain and how lipids affect brain function. Finally, we focus on the current status of lipidomics findings in human brain aging and Alzheimer's disease pathology. Neurolipidomics will increase knowledge about physiological and pathological functions of brain cells and will place the concept of selective neuronal vulnerability in a lipid context.

  14. Alzheimer's disease.

    PubMed

    Scheltens, Philip; Blennow, Kaj; Breteler, Monique M B; de Strooper, Bart; Frisoni, Giovanni B; Salloway, Stephen; Van der Flier, Wiesje Maria

    2016-07-30

    Although the prevalence of dementia continues to increase worldwide, incidence in the western world might have decreased as a result of better vascular care and improved brain health. Alzheimer's disease, the most prevalent cause of dementia, is still defined by the combined presence of amyloid and tau, but researchers are gradually moving away from the simple assumption of linear causality as proposed in the original amyloid hypothesis. Age-related, protective, and disease-promoting factors probably interact with the core mechanisms of the disease. Amyloid β42, and tau proteins are established core cerebrospinal biomarkers; novel candidate biomarkers include amyloid β oligomers and synaptic markers. MRI and fluorodeoxyglucose PET are established imaging techniques for diagnosis of Alzheimer's disease. Amyloid PET is gaining traction in the clinical arena, but validity and cost-effectiveness remain to be established. Tau PET might offer new insights and be of great help in differential diagnosis and selection of patients for trials. In the search for understanding the disease mechanism and keys to treatment, research is moving increasingly into the earliest phase of disease. Preclinical Alzheimer's disease is defined as biomarker evidence of Alzheimer's pathological changes in cognitively healthy individuals. Patients with subjective cognitive decline have been identified as a useful population in whom to look for preclinical Alzheimer's disease. Moderately positive results for interventions targeting several lifestyle factors in non-demented elderly patients and moderately positive interim results for lowering amyloid in pre-dementia Alzheimer's disease suggest that, ultimately, there will be a future in which specific anti-Alzheimer's therapy will be combined with lifestyle interventions targeting general brain health to jointly combat the disease. In this Seminar, we discuss the main developments in Alzheimer's research. PMID:26921134

  15. Alzheimer's disease.

    PubMed

    Scheltens, Philip; Blennow, Kaj; Breteler, Monique M B; de Strooper, Bart; Frisoni, Giovanni B; Salloway, Stephen; Van der Flier, Wiesje Maria

    2016-07-30

    Although the prevalence of dementia continues to increase worldwide, incidence in the western world might have decreased as a result of better vascular care and improved brain health. Alzheimer's disease, the most prevalent cause of dementia, is still defined by the combined presence of amyloid and tau, but researchers are gradually moving away from the simple assumption of linear causality as proposed in the original amyloid hypothesis. Age-related, protective, and disease-promoting factors probably interact with the core mechanisms of the disease. Amyloid β42, and tau proteins are established core cerebrospinal biomarkers; novel candidate biomarkers include amyloid β oligomers and synaptic markers. MRI and fluorodeoxyglucose PET are established imaging techniques for diagnosis of Alzheimer's disease. Amyloid PET is gaining traction in the clinical arena, but validity and cost-effectiveness remain to be established. Tau PET might offer new insights and be of great help in differential diagnosis and selection of patients for trials. In the search for understanding the disease mechanism and keys to treatment, research is moving increasingly into the earliest phase of disease. Preclinical Alzheimer's disease is defined as biomarker evidence of Alzheimer's pathological changes in cognitively healthy individuals. Patients with subjective cognitive decline have been identified as a useful population in whom to look for preclinical Alzheimer's disease. Moderately positive results for interventions targeting several lifestyle factors in non-demented elderly patients and moderately positive interim results for lowering amyloid in pre-dementia Alzheimer's disease suggest that, ultimately, there will be a future in which specific anti-Alzheimer's therapy will be combined with lifestyle interventions targeting general brain health to jointly combat the disease. In this Seminar, we discuss the main developments in Alzheimer's research.

  16. Benefits from dietary polyphenols for brain aging and Alzheimer's disease.

    PubMed

    Rossi, L; Mazzitelli, S; Arciello, M; Capo, C R; Rotilio, G

    2008-12-01

    Brain aging and the most diffused neurodegenerative diseases of the elderly are characterized by oxidative damage, redox metals homeostasis impairment and inflammation. Food polyphenols can counteract these alterations in vitro and are therefore suggested to have potential anti-aging and brain-protective activities, as also indicated by the results of some epidemiological studies. Despite the huge and increasing amount of the in vitro studies trying to unravel the mechanisms of action of dietary polyphenols, the research in this field is still incomplete, and questions about bioavailability, biotransformation, synergism with other dietary factors, mechanisms of the antioxidant activity, risks inherent to their possible pro-oxidant activities are still unanswered. Most of all, the capacity of the majority of these compounds to cross the blood-brain barrier and reach brain is still unknown. This commentary discusses recent data on these aspects, particularly focusing on effects of curcumin, resveratrol and catechins on Alzheimer's disease.

  17. Mapping cortical change in Alzheimer's disease, brain development, and schizophrenia.

    PubMed

    Thompson, Paul M; Hayashi, Kiralee M; Sowell, Elizabeth R; Gogtay, Nitin; Giedd, Jay N; Rapoport, Judith L; de Zubicaray, Greig I; Janke, Andrew L; Rose, Stephen E; Semple, James; Doddrell, David M; Wang, Yalin; van Erp, Theo G M; Cannon, Tyrone D; Toga, Arthur W

    2004-01-01

    This paper describes algorithms that can identify patterns of brain structure and function associated with Alzheimer's disease, schizophrenia, normal aging, and abnormal brain development based on imaging data collected in large human populations. Extraordinary information can be discovered with these techniques: dynamic brain maps reveal how the brain grows in childhood, how it changes in disease, and how it responds to medication. Genetic brain maps can reveal genetic influences on brain structure, shedding light on the nature-nurture debate, and the mechanisms underlying inherited neurobehavioral disorders. Recently, we created time-lapse movies of brain structure for a variety of diseases. These identify complex, shifting patterns of brain structural deficits, revealing where, and at what rate, the path of brain deterioration in illness deviates from normal. Statistical criteria can then identify situations in which these changes are abnormally accelerated, or when medication or other interventions slow them. In this paper, we focus on describing our approaches to map structural changes in the cortex. These methods have already been used to reveal the profile of brain anomalies in studies of dementia, epilepsy, depression, childhood- and adult-onset schizophrenia, bipolar disorder, attention-deficit/hyperactivity disorder, fetal alcohol syndrome, Tourette syndrome, Williams syndrome, and in methamphetamine abusers. Specifically, we describe an image analysis pipeline known as cortical pattern matching that helps compare and pool cortical data over time and across subjects. Statistics are then defined to identify brain structural differences between groups, including localized alterations in cortical thickness, gray matter density (GMD), and asymmetries in cortical organization. Subtle features, not seen in individual brain scans, often emerge when population-based brain data are averaged in this way. Illustrative examples are presented to show the profound

  18. Genetic variants in Alzheimer disease - molecular and brain network approaches.

    PubMed

    Gaiteri, Chris; Mostafavi, Sara; Honey, Christopher J; De Jager, Philip L; Bennett, David A

    2016-07-01

    Genetic studies in late-onset Alzheimer disease (LOAD) are aimed at identifying core disease mechanisms and providing potential biomarkers and drug candidates to improve clinical care of AD. However, owing to the complexity of LOAD, including pathological heterogeneity and disease polygenicity, extraction of actionable guidance from LOAD genetics has been challenging. Past attempts to summarize the effects of LOAD-associated genetic variants have used pathway analysis and collections of small-scale experiments to hypothesize functional convergence across several variants. In this Review, we discuss how the study of molecular, cellular and brain networks provides additional information on the effects of LOAD-associated genetic variants. We then discuss emerging combinations of these omic data sets into multiscale models, which provide a more comprehensive representation of the effects of LOAD-associated genetic variants at multiple biophysical scales. Furthermore, we highlight the clinical potential of mechanistically coupling genetic variants and disease phenotypes with multiscale brain models. PMID:27282653

  19. Brain inflammation in Alzheimer disease and the therapeutic implications.

    PubMed

    McGeer, E G; McGeer, P L

    1999-10-01

    Immunohistochemical studies suggested the existence of a chronic inflammatory condition in affected regions of the brain in Alzheimer disease (AD). Since inflammation can be damaging to host tissue, it was hypothesized that antiinflammatory drugs might inhibit both the onset and the progression of AD. This hypothesis is supported by a number of epidemiological studies suggesting that the prevalence of AD in persons is reduced by 40 - 50% in persons using antiinflammatory drugs. In one small pilot trial in early AD, the nonsteroidal antiinflammatory drug indomethacin appeared to halt the progressive memory loss. Immunohistochemical and molecular biological studies on immune system components in AD brain are revealing the complexities of the innate immune reaction. This very complexity may offer points of therapeutic intervention for new types of antiinflammatory agents. The complement system, microglia and cytokines are key components. This review summarizes the present state of knowledge on the immune system elements found in AD brain.

  20. Regional brain stiffness changes across the Alzheimer's disease spectrum☆

    PubMed Central

    Murphy, Matthew C.; Jones, David T.; Jack, Clifford R.; Glaser, Kevin J.; Senjem, Matthew L.; Manduca, Armando; Felmlee, Joel P.; Carter, Rickey E.; Ehman, Richard L.; Huston, John

    2015-01-01

    Magnetic resonance elastography (MRE) is an MRI-based technique to noninvasively measure tissue stiffness. Currently well established for clinical use in the liver, MRE is increasingly being investigated to measure brain stiffness as a novel biomarker of a variety of neurological diseases. The purpose of this work was to apply a recently developed MRE pipeline to measure regional brain stiffness changes in human subjects across the Alzheimer's disease (AD) spectrum, and to gain insights into the biological processes underlying those stiffness changes by correlating stiffness with existing biomarkers of AD. The results indicate that stiffness changes occur mostly in the frontal, parietal and temporal lobes, in accordance with the known topography of AD pathology. Furthermore, stiffness in those areas correlates with existing imaging biomarkers of AD including hippocampal volumes and amyloid PET. Additional analysis revealed preliminary but significant evidence that the relationship between brain stiffness and AD severity is nonlinear and non-monotonic. Given that similar relationships have been observed in functional MRI experiments, we used task-free fMRI data to test the hypothesis that brain stiffness was sensitive to structural changes associated with altered functional connectivity. The analysis revealed that brain stiffness is significantly and positively correlated with default mode network connectivity. Therefore, brain stiffness as measured by MRE has potential to provide new and essential insights into the temporal dynamics of AD, as well as the relationship between functional and structural plasticity as it relates to AD pathophysiology. PMID:26900568

  1. Regional brain stiffness changes across the Alzheimer's disease spectrum.

    PubMed

    Murphy, Matthew C; Jones, David T; Jack, Clifford R; Glaser, Kevin J; Senjem, Matthew L; Manduca, Armando; Felmlee, Joel P; Carter, Rickey E; Ehman, Richard L; Huston, John

    2016-01-01

    Magnetic resonance elastography (MRE) is an MRI-based technique to noninvasively measure tissue stiffness. Currently well established for clinical use in the liver, MRE is increasingly being investigated to measure brain stiffness as a novel biomarker of a variety of neurological diseases. The purpose of this work was to apply a recently developed MRE pipeline to measure regional brain stiffness changes in human subjects across the Alzheimer's disease (AD) spectrum, and to gain insights into the biological processes underlying those stiffness changes by correlating stiffness with existing biomarkers of AD. The results indicate that stiffness changes occur mostly in the frontal, parietal and temporal lobes, in accordance with the known topography of AD pathology. Furthermore, stiffness in those areas correlates with existing imaging biomarkers of AD including hippocampal volumes and amyloid PET. Additional analysis revealed preliminary but significant evidence that the relationship between brain stiffness and AD severity is nonlinear and non-monotonic. Given that similar relationships have been observed in functional MRI experiments, we used task-free fMRI data to test the hypothesis that brain stiffness was sensitive to structural changes associated with altered functional connectivity. The analysis revealed that brain stiffness is significantly and positively correlated with default mode network connectivity. Therefore, brain stiffness as measured by MRE has potential to provide new and essential insights into the temporal dynamics of AD, as well as the relationship between functional and structural plasticity as it relates to AD pathophysiology.

  2. Vascular and Alzheimer's disease markers independently predict brain atrophy rate in Alzheimer's Disease Neuroimaging Initiative controls.

    PubMed

    Barnes, Josephine; Carmichael, Owen T; Leung, Kelvin K; Schwarz, Christopher; Ridgway, Gerard R; Bartlett, Jonathan W; Malone, Ian B; Schott, Jonathan M; Rossor, Martin N; Biessels, Geert Jan; DeCarli, Charlie; Fox, Nick C

    2013-08-01

    This study assessed relationships among white matter hyperintensities (WMH), cerebrospinal fluid (CSF), Alzheimer's disease (AD) pathology markers, and brain volume loss. Subjects included 197 controls, 331 individuals with mild cognitive impairment (MCI), and 146 individuals with AD with serial volumetric 1.5-T MRI. CSF Aβ1-42 (n = 351) and tau (n = 346) were measured. Brain volume change was quantified using the boundary shift integral (BSI). We assessed the association between baseline WMH volume and annualized BSI, adjusting for intracranial volume. We also performed multiple regression analyses in the CSF subset, assessing the relationships of WMH and Aβ1-42 and/or tau with BSI. WMH burden was positively associated with BSI in controls (p = 0.02) but not MCI or AD. In multivariable models, WMH (p = 0.003) and Aβ1-42 (p = 0.001) were independently associated with BSI in controls; in MCI Aβ1-42 (p < 0.001) and tau (p = 0.04) were associated with BSI. There was no evidence of independent effects of WMH or CSF measures on BSI in AD. These data support findings that vascular damage is associated with increased brain atrophy in the context of AD pathology in pre-dementia stages.

  3. Altered brain energetics induces mitochondrial fission arrest in Alzheimer's Disease.

    PubMed

    Zhang, Liang; Trushin, Sergey; Christensen, Trace A; Bachmeier, Benjamin V; Gateno, Benjamin; Schroeder, Andreas; Yao, Jia; Itoh, Kie; Sesaki, Hiromi; Poon, Wayne W; Gylys, Karen H; Patterson, Emily R; Parisi, Joseph E; Diaz Brinton, Roberta; Salisbury, Jeffrey L; Trushina, Eugenia

    2016-01-01

    Altered brain metabolism is associated with progression of Alzheimer's Disease (AD). Mitochondria respond to bioenergetic changes by continuous fission and fusion. To account for three dimensional architecture of the brain tissue and organelles, we applied 3-dimensional electron microscopy (3D EM) reconstruction to visualize mitochondrial structure in the brain tissue from patients and mouse models of AD. We identified a previously unknown mitochondrial fission arrest phenotype that results in elongated interconnected organelles, "mitochondria-on-a-string" (MOAS). Our data suggest that MOAS formation may occur at the final stages of fission process and was not associated with altered translocation of activated dynamin related protein 1 (Drp1) to mitochondria but with reduced GTPase activity. Since MOAS formation was also observed in the brain tissue of wild-type mice in response to hypoxia or during chronological aging, fission arrest may represent fundamental compensatory adaptation to bioenergetic stress providing protection against mitophagy that may preserve residual mitochondrial function. The discovery of novel mitochondrial phenotype that occurs in the brain tissue in response to energetic stress accurately detected only using 3D EM reconstruction argues for a major role of mitochondrial dynamics in regulating neuronal survival. PMID:26729583

  4. Alzheimer's disease pattern of brain atrophy predicts cognitive decline in Parkinson's disease.

    PubMed

    Weintraub, Daniel; Dietz, Nicole; Duda, John E; Wolk, David A; Doshi, Jimit; Xie, Sharon X; Davatzikos, Christos; Clark, Christopher M; Siderowf, Andrew

    2012-01-01

    Research suggests overlap in brain regions undergoing neurodegeneration in Parkinson's and Alzheimer's disease. To assess the clinical significance of this, we applied a validated Alzheimer's disease-spatial pattern of brain atrophy to patients with Parkinson's disease with a range of cognitive abilities to determine its association with cognitive performance and decline. At baseline, 84 subjects received structural magnetic resonance imaging brain scans and completed the Dementia Rating Scale-2, and new robust and expanded Dementia Rating Scale-2 norms were applied to cognitively classify participants. Fifty-nine non-demented subjects were assessed annually with the Dementia Rating Scale-2 for two additional years. Magnetic resonance imaging scans were quantified using both a region of interest approach and voxel-based morphometry analysis, and a method for quantifying the presence of an Alzheimer's disease spatial pattern of brain atrophy was applied to each scan. In multivariate models, higher Alzheimer's disease pattern of atrophy score was associated with worse global cognitive performance (β = -0.31, P = 0.007), including in non-demented patients (β = -0.28, P = 0.05). In linear mixed model analyses, higher baseline Alzheimer's disease pattern of atrophy score predicted long-term global cognitive decline in non-demented patients [F(1, 110) = 9.72, P = 0.002], remarkably even in those with normal cognition at baseline [F(1, 80) = 4.71, P = 0.03]. In contrast, in cross-sectional and longitudinal analyses there was no association between region of interest brain volumes and cognitive performance in patients with Parkinson's disease with normal cognition. These findings support involvement of the hippocampus and parietal-temporal cortex with cognitive impairment and long-term decline in Parkinson's disease. In addition, an Alzheimer's disease pattern of brain atrophy may be a preclinical biomarker of cognitive decline in

  5. Humoral immunity in brain aging and Alzheimer's disease.

    PubMed

    Bouras, Constantin; Riederer, Beat M; Kövari, Enikö; Hof, Patrick R; Giannakopoulos, Panteleimon

    2005-06-01

    Although the contribution of inflammatory processes in the etiology of late-onset Alzheimer's disease (AD) has been suspected for years, most studies were confined to the analysis of cell-mediated immunological reactions thought to represent an epiphenomenon of AD lesion development. Based on the traditional view of the "immunological privilege" of the brain, which excludes a direct access of human immunoglobulins (Ig) to the central nervous system under normal conditions, little attention has been paid to a possible role of humoral immunity in AD pathogenesis. In the first part of this review, we summarize evidences for a blood-brain barrier (BBB) dysfunction in this disorder and critically comment on earlier observations supporting the presence of anti-brain autoantibodies and immunoglobulins (Ig) in AD brains. Current concepts regarding the Ig turnover in the central nervous system and the mechanisms of glial and neuronal Fc receptors activation are also discussed. In the second part, we present new ex vivo and in vitro data suggesting that human immunoglobulins can interact with tau protein and alter both the dynamics and structural organization of microtubules. Subsequent experiments needed to test this new working hypothesis are addressed at the end of the review.

  6. Altered subcellular localization of ornithine decarboxylase in Alzheimer's disease brain

    SciTech Connect

    Nilsson, Tatjana . E-mail: Tatjana.Nilsson@ki.se; Bogdanovic, Nenad; Volkman, Inga; Winblad, Bengt; Folkesson, Ronnie; Benedikz, Eirikur

    2006-06-02

    The amyloid precursor protein can through ligand-mimicking induce expression of ornithine decarboxylase (ODC), the initial and rate-limiting enzyme in polyamine biosynthesis. We report here the regional distribution and cellular localization of ODC immunoreactivity in Alzheimer's disease (AD) brains. In frontal cortex and hippocampus of control cases, the most pronounced ODC immunoreactivity was found in the nucleus. In possible and definite AD the immunoreactivity had shifted to the cytoplasm. In cerebellum of control cases, ODC staining was found in a small portion of Purkinje cells, mostly in the nucleus. In AD, both possible and definite, the number of stained Purkinje cells increased significantly and immunoreactivity was shifted to the cytoplasm, even though it was still prominent in the nucleus. In conclusion, our study reveals an early shift of the ODC immunoreactivity in AD from the nuclear compartment towards the cytoplasm.

  7. Fibrin deposited in the Alzheimer's disease brain promotes neuronal degeneration.

    PubMed

    Cortes-Canteli, Marta; Mattei, Larissa; Richards, Allison T; Norris, Erin H; Strickland, Sidney

    2015-02-01

    Alzheimer's disease (AD) is the most common form of dementia and has no effective treatment. Besides the well-known pathologic characteristics, this disease also has a vascular component, and substantial evidence shows increased thrombosis as well as a critical role for fibrin(ogen) in AD. This molecule has been implicated in neuroinflammation, neurovascular damage, blood-brain barrier permeability, vascular amyloid deposition, and memory deficits that are observed in AD. Here, we present evidence demonstrating that fibrin deposition increases in the AD brain and correlates with the degree of pathology. Moreover, we show that fibrin(ogen) is present in areas of dystrophic neurites and that a modest decrease in fibrinogen levels improves neuronal health and ameliorates amyloid pathology in the subiculum of AD mice. Our results further characterize the important role of fibrin(ogen) in this disease and support the design of therapeutic strategies aimed at blocking the interaction between fibrinogen and amyloid-β (Aβ) and/or normalizing the increased thrombosis present in AD. PMID:25475538

  8. Brain tocopherols related to Alzheimer's disease neuropathology in humans.

    PubMed

    Morris, Martha Clare; Schneider, Julie A; Li, Hong; Tangney, Christy C; Nag, Sukriti; Bennett, David A; Honer, William G; Barnes, Lisa L

    2015-01-01

    Randomized trials of α-tocopherol supplements on cognitive decline are negative, whereas studies of dietary tocopherols have shown benefit. We investigated these inconsistencies by analyzing the relations of α- and γ-tocopherol brain concentrations to Alzheimer's disease (AD) neuropathology among 115 deceased participants of the prospective Rush Memory and Aging Project. Associations of amyloid load and neurofibrillary tangle severity with brain tocopherol concentrations were examined in separate adjusted linear regression models. γ-Tocopherol concentrations were associated with lower amyloid load (β = -2.10, P = .002) and lower neurofibrillary tangle severity (β = -1.16, P = .02). Concentrations of α-tocopherol were not associated with AD neuropathology, except as modified by γ-tocopherol: high α-tocopherol was associated with higher amyloid load when γ-tocopherol levels were low and with lower amyloid levels when γ-tocopherol levels were high (P for interaction = 0.03). Brain concentrations of γ- and α-tocopherols may be associated with AD neuropathology in interrelated, complex ways. Randomized trials should consider the contribution of γ-tocopherol.

  9. Tau protein in normal and Alzheimer's disease brain: an update.

    PubMed

    Johnson, G V; Hartigan, J A

    1999-11-01

    Tau is a microtubule-associated protein that, in a hyperphosphorylated form, comprises the main component of the paired helical filaments and neurofibrillary tangles found in Alzheimer's Disease (AD) brain. It is therefore important to understand the normal functioning and processing of tau protein, and the abnormal posttranslational processing of tau in AD pathology. In 1996, Johnson and Jenkins reviewed the literature on the biochemistry, function, and phosphorylation of tau in normal and AD brain. Since that time, numerous publications have come out further elucidating the properties of tau. The present review updates the topics originally covered in the 1996 review, as well as presents a number of new topics. For example, mutations in the tau gene have been found in several non-AD, autosomal dominant neurodegenerative disorders that exhibit extensive neurofibrillary pathology. In addition, there is increasing evidence that tau may be involved in signal transduction, organelle transport, and cell growth, independent of its microtubule-binding functions. Taken together, the research reviewed here demonstrates that tau is a very complex protein with various functions that are intricately regulated. It is clear that more research is required to completely understand the functions and regulation of tau in normal and AD brain.

  10. Altered brain response for semantic knowledge in Alzheimer's disease.

    PubMed

    Wierenga, Christina E; Stricker, Nikki H; McCauley, Ashley; Simmons, Alan; Jak, Amy J; Chang, Yu-Ling; Nation, Daniel A; Bangen, Katherine J; Salmon, David P; Bondi, Mark W

    2011-02-01

    Word retrieval deficits are common in Alzheimer's disease (AD) and are thought to reflect a degradation of semantic memory. Yet, the nature of semantic deterioration in AD and the underlying neural correlates of these semantic memory changes remain largely unknown. We examined the semantic memory impairment in AD by investigating the neural correlates of category knowledge (e.g., living vs. nonliving) and featural processing (global vs. local visual information). During event-related fMRI, 10 adults diagnosed with mild AD and 22 cognitively normal (CN) older adults named aloud items from three categories for which processing of specific visual features has previously been dissociated from categorical features. Results showed widespread group differences in the categorical representation of semantic knowledge in several language-related brain areas. For example, the right inferior frontal gyrus showed selective brain response for nonliving items in the CN group but living items in the AD group. Additionally, the AD group showed increased brain response for word retrieval irrespective of category in Broca's homologue in the right hemisphere and rostral cingulate cortex bilaterally, which suggests greater recruitment of frontally mediated neural compensatory mechanisms in the face of semantic alteration. PMID:21163275

  11. Topographic regulation of kinase activity in Alzheimer's disease brains.

    PubMed

    Grant, Philip; Pant, Harish C

    2002-08-01

    At autopsy, a most distinctive pathology seen in Alzheimer's disease (AD) brains is numerous abnormal neurons filled with neurofibrillary tangles (NFTs) containing stable complexes of hyperphosphorylated tau (PHF), neurofilaments and various kinases, among other proteins. Though these neuronal aggregates have been actively studied, their nature and origin are still poorly understood. Our studies of regulation of phosphorylation in neurons of the squid giant fiber system, using P13(suc1) affinity chromatography, suggest that neuronal phosphorylation of cytoskeletal proteins is compartmentalized into active axonal and inactive cell body-specific multimeric complexes of kinases, substrates and phosphatases. To determine whether such compartment-specific phosphorylation complexes are present in human brains, we separated gray matter (enriched in cell bodies) and white matter (enriched in axons) from normal and AD brains and studied the total kinase activities in lysates, pellets and P13(suc1) complexes. In addition, Western blot analysis was used to characterize the proteins associated with P13(suc1) multimeric complexes extracted from gray and white matter. We tested the hypothesis that P13 phosphorylation complexes were abnormally compartmentalized in AD neurons with the more active complexes shifted to cell bodies (gray matter) instead of axons (white matter). We found that (1) endogenous and exogenous substrate-dependent kinase activities of AD and control brain extracts were similar in both gray and white matter. (2) Long post mortem times tend to erase any differences in kinase activity between control and AD extracts. In contrast to shorter post mortem times (4.5-10 hrs), long post mortem times (13-34 hrs) significantly minimize the variances in kinase activities between control and AD brain extracts suggesting that cell death and proteolysis may eliminate any intrinsic differences in enzyme activities. (3) Except for the significantly higher level of histone

  12. Neurodegeneration and Alzheimer's disease (AD). What Can Proteomics Tell Us About the Alzheimer's Brain?

    PubMed

    Moya-Alvarado, Guillermo; Gershoni-Emek, Noga; Perlson, Eran; Bronfman, Francisca C

    2016-02-01

    Neurodegenerative diseases, such as Alzheimer's diseases (AD), are becoming more prevalent as the population ages. However, the mechanisms that lead to synapse destabilization and neuron death remain elusive. The advent of proteomics has allowed for high-throughput screening methods to search for biomarkers that could lead to early diagnosis and treatment and to identify alterations in the cellular proteome that could provide insight into disease etiology and possible treatment avenues. In this review, we have concentrated mainly on the findings that are related to how and whether proteomics studies have contributed to two aspects of AD research, the development of biomarkers for clinical diagnostics, and the recognition of proteins that can help elucidate the pathways leading to AD brain pathology. As a result of these studies, several candidate cerebrospinal fluid biomarkers are now available for further validation in different AD cohorts. Studies in AD brain and AD transgenic models support the notion that oxidative damage results in the alterations of metabolic enzymes and that mitochondrial dysfunction is central to AD neuropathology. PMID:26657538

  13. Data set of interactomes and metabolic pathways of proteins differentially expressed in brains with Alzheimer׳s disease.

    PubMed

    Minjarez, Benito; Calderón-González, Karla Grisel; Valero Rustarazo, Ma Luz; Herrera-Aguirre, María Esther; Labra-Barrios, María Luisa; Rincon-Limas, Diego E; Sánchez Del Pino, Manuel M; Mena, Raul; Luna-Arias, Juan Pedro

    2016-06-01

    Alzheimer׳s disease is one of the main causes of dementia in the elderly and its frequency is on the rise worldwide. It is considered the result of complex interactions between genetic and environmental factors, being many of them unknown. Therefore, there is a dire necessity for the identification of novel molecular players for the understanding of this disease. In this data article we determined the protein expression profiles of whole protein extracts from cortex regions of brains from patients with Alzheimer׳s disease in comparison to a normal brain. We identified 721 iTRAQ-labeled polypeptides with more than 95% in confidence. We analyzed all proteins that changed in their expression level and located them in the KEGG metabolic pathways, as well as in the mitochondrial complexes of the electron transport chain and ATP synthase. In addition, we analyzed the over- and sub-expressed polypeptides through IPA software, specifically Core I and Biomarkers I modules. Data in this article is related to the research article "Identification of proteins that are differentially expressed in brains with Alzheimer's disease using iTRAQ labeling and tandem mass spectrometry" (Minjarez et al., 2016) [1]. PMID:27257613

  14. Data set of interactomes and metabolic pathways of proteins differentially expressed in brains with Alzheimer׳s disease.

    PubMed

    Minjarez, Benito; Calderón-González, Karla Grisel; Valero Rustarazo, Ma Luz; Herrera-Aguirre, María Esther; Labra-Barrios, María Luisa; Rincon-Limas, Diego E; Sánchez Del Pino, Manuel M; Mena, Raul; Luna-Arias, Juan Pedro

    2016-06-01

    Alzheimer׳s disease is one of the main causes of dementia in the elderly and its frequency is on the rise worldwide. It is considered the result of complex interactions between genetic and environmental factors, being many of them unknown. Therefore, there is a dire necessity for the identification of novel molecular players for the understanding of this disease. In this data article we determined the protein expression profiles of whole protein extracts from cortex regions of brains from patients with Alzheimer׳s disease in comparison to a normal brain. We identified 721 iTRAQ-labeled polypeptides with more than 95% in confidence. We analyzed all proteins that changed in their expression level and located them in the KEGG metabolic pathways, as well as in the mitochondrial complexes of the electron transport chain and ATP synthase. In addition, we analyzed the over- and sub-expressed polypeptides through IPA software, specifically Core I and Biomarkers I modules. Data in this article is related to the research article "Identification of proteins that are differentially expressed in brains with Alzheimer's disease using iTRAQ labeling and tandem mass spectrometry" (Minjarez et al., 2016) [1].

  15. A derangement of the brain wound healing process may cause some cases of Alzheimer's disease.

    PubMed

    Lehrer, Steven; Rheinstein, Peter H

    2016-08-01

    A derangement of brain wound healing may cause some cases of Alzheimer's disease. Wound healing, a highly complex process, has four stages: hemostasis, inflammation, repair, and remodeling. Hemostasis and the initial phases of inflammation in brain tissue are typical of all vascularized tissue, such as skin. However, distinct differences arise in brain tissue during the later stages of inflammation, repair, and remodeling, and closely parallel the changes of Alzheimer's disease. Our hypothesis -- Alzheimer's disease is brain wound healing gone awry at least in some cases -- could be tested by measuring progression with biomarkers for the four stages of wound healing in humans or appropriate animal models. Autopsy studies might be done. Chronic traumatic encephalopathy might also result from the brain wound healing process. PMID:27585229

  16. Imaging the Alzheimer Brain

    PubMed Central

    Ashford, J. Wesson; Salehi, Ahmad; Furst, Ansgar; Bayley, Peter; Frisoni, Giovanni B.; Jack, Clifford R.; Sabri, Osama; Adamson, Maheen M.; Coburn, Kerry L.; Olichney, John; Schuff, Norbert; Spielman, Daniel; Edland, Steven D.; Black, Sandra; Rosen, Allyson; Kennedy, David; Weiner, Michael; Perry, George

    2013-01-01

    This supplement to the Journal of Alzheimer's Disease contains more than half of the chapters from The Handbook of Imaging the Alzheimer Brain, which was first presented at the International Conference on Alzheimer's Disease in Paris, in July, 2011. While the Handbook contains 27 chapters that are modified articles from 2009, 2010, and 2011 issues of the Journal of Alzheimer's Disease, this supplement contains the 31 new chapters of that book and an introductory article drawn from the introductions to each section of the book. The Handbook was designed to provide a multilevel overview of the full field of brain imaging related to Alzheimer's disease (AD). The Handbook, as well as this supplement, contains both reviews of the basic concepts of imaging, the latest developments in imaging, and various discussions and perspectives of the problems of the field and promising directions. The Handbook was designed to be useful for students and clinicians interested in AD as well as scientists studying the brain and pathology related to AD. PMID:21971448

  17. The conflicting role of brain cholesterol in Alzheimer's disease: lessons from the brain plasminogen system.

    PubMed

    Ledesma, Maria Dolores; Dotti, Carlos G

    2005-01-01

    Retrospective clinical studies indicate that individuals chronically treated with cholesterol synthesis inhibitors, statins, are at lower risk of developing AD (Alzheimer's disease). Moreover, treatment of guinea pigs with high doses of simvastatin or drastic reduction of cholesterol in cultured cells decrease Abeta (beta-amyloid peptide) production. These data sustain the concept that high brain cholesterol is responsible for Abeta accumulation in AD, providing the scientific support for the proposed use of statins to prevent this disease. However, a number of unresolved issues raise doubts that high brain cholesterol is to blame. First, it has not been shown that higher neuronal cholesterol increases Abeta production. Secondly, it has not been demonstrated that neurons in AD have more cholesterol than control neurons. On the contrary, the brains of AD patients show a specific down-regulation of seladin-1, a protein involved in cholesterol synthesis, and low membrane cholesterol was observed in hippocampal membranes of ApoE4 (apolipoprotein E4) AD cases. This effect was also evidenced by altered cholesterol-rich membrane domains (rafts) and raft-mediated functions, such as diminished generation of the Abeta-degrading enzyme plasmin. Thirdly, numerous genetic defects that cause neurodegeneration are due to defective cholesterol metabolism. Fourthly, in female mice, the most brain-permeant statin induces neurodegeneration and high amyloid production. Altogether, this evidence makes it difficult to accept that statins are beneficial through acting as brain cholesterol-synthesis inhibitors. It appears more likely that their advantageous role arises from improved brain oxygenation.

  18. Blood-brain barrier P-glycoprotein function in Alzheimer's disease.

    PubMed

    van Assema, Daniëlle M E; Lubberink, Mark; Bauer, Martin; van der Flier, Wiesje M; Schuit, Robert C; Windhorst, Albert D; Comans, Emile F I; Hoetjes, Nikie J; Tolboom, Nelleke; Langer, Oliver; Müller, Markus; Scheltens, Philip; Lammertsma, Adriaan A; van Berckel, Bart N M

    2012-01-01

    A major pathological hallmark of Alzheimer's disease is accumulation of amyloid-β in senile plaques in the brain. Evidence is accumulating that decreased clearance of amyloid-β from the brain may lead to these elevated amyloid-β levels. One of the clearance pathways of amyloid-β is transport across the blood-brain barrier via efflux transporters. P-glycoprotein, an efflux pump highly expressed at the endothelial cells of the blood-brain barrier, has been shown to transport amyloid-β. P-glycoprotein function can be assessed in vivo using (R)-[(11)C]verapamil and positron emission tomography. The aim of this study was to assess blood-brain barrier P-glycoprotein function in patients with Alzheimer's disease compared with age-matched healthy controls using (R)-[(11)C]verapamil and positron emission tomography. In 13 patients with Alzheimer's disease (age 65 ± 7 years, Mini-Mental State Examination 23 ± 3), global (R)-[(11)C]verapamil binding potential values were increased significantly (P = 0.001) compared with 14 healthy controls (aged 62 ± 4 years, Mini-Mental State Examination 30 ± 1). Global (R)-[(11)C]verapamil binding potential values were 2.18 ± 0.25 for patients with Alzheimer's disease and 1.77 ± 0.41 for healthy controls. In patients with Alzheimer's disease, higher (R)-[(11)C]verapamil binding potential values were found for frontal, parietal, temporal and occipital cortices, and posterior and anterior cingulate. No significant differences between groups were found for medial temporal lobe and cerebellum. These data show altered kinetics of (R)-[(11)C]verapamil in Alzheimer's disease, similar to alterations seen in studies where P-glycoprotein is blocked by a pharmacological agent. As such, these data indicate that P-glycoprotein function is decreased in patients with Alzheimer's disease. This is the first direct evidence that the P-glycoprotein transporter at the blood-brain barrier is compromised in sporadic

  19. White Matter Lipids as a Ketogenic Fuel Supply in Aging Female Brain: Implications for Alzheimer's Disease.

    PubMed

    Klosinski, Lauren P; Yao, Jia; Yin, Fei; Fonteh, Alfred N; Harrington, Michael G; Christensen, Trace A; Trushina, Eugenia; Brinton, Roberta Diaz

    2015-12-01

    White matter degeneration is a pathological hallmark of neurodegenerative diseases including Alzheimer's. Age remains the greatest risk factor for Alzheimer's and the prevalence of age-related late onset Alzheimer's is greatest in females. We investigated mechanisms underlying white matter degeneration in an animal model consistent with the sex at greatest Alzheimer's risk. Results of these analyses demonstrated decline in mitochondrial respiration, increased mitochondrial hydrogen peroxide production and cytosolic-phospholipase-A2 sphingomyelinase pathway activation during female brain aging. Electron microscopic and lipidomic analyses confirmed myelin degeneration. An increase in fatty acids and mitochondrial fatty acid metabolism machinery was coincident with a rise in brain ketone bodies and decline in plasma ketone bodies. This mechanistic pathway and its chronologically phased activation, links mitochondrial dysfunction early in aging with later age development of white matter degeneration. The catabolism of myelin lipids to generate ketone bodies can be viewed as a systems level adaptive response to address brain fuel and energy demand. Elucidation of the initiating factors and the mechanistic pathway leading to white matter catabolism in the aging female brain provides potential therapeutic targets to prevent and treat demyelinating diseases such as Alzheimer's and multiple sclerosis. Targeting stages of disease and associated mechanisms will be critical. PMID:26844268

  20. White Matter Lipids as a Ketogenic Fuel Supply in Aging Female Brain: Implications for Alzheimer's Disease.

    PubMed

    Klosinski, Lauren P; Yao, Jia; Yin, Fei; Fonteh, Alfred N; Harrington, Michael G; Christensen, Trace A; Trushina, Eugenia; Brinton, Roberta Diaz

    2015-12-01

    White matter degeneration is a pathological hallmark of neurodegenerative diseases including Alzheimer's. Age remains the greatest risk factor for Alzheimer's and the prevalence of age-related late onset Alzheimer's is greatest in females. We investigated mechanisms underlying white matter degeneration in an animal model consistent with the sex at greatest Alzheimer's risk. Results of these analyses demonstrated decline in mitochondrial respiration, increased mitochondrial hydrogen peroxide production and cytosolic-phospholipase-A2 sphingomyelinase pathway activation during female brain aging. Electron microscopic and lipidomic analyses confirmed myelin degeneration. An increase in fatty acids and mitochondrial fatty acid metabolism machinery was coincident with a rise in brain ketone bodies and decline in plasma ketone bodies. This mechanistic pathway and its chronologically phased activation, links mitochondrial dysfunction early in aging with later age development of white matter degeneration. The catabolism of myelin lipids to generate ketone bodies can be viewed as a systems level adaptive response to address brain fuel and energy demand. Elucidation of the initiating factors and the mechanistic pathway leading to white matter catabolism in the aging female brain provides potential therapeutic targets to prevent and treat demyelinating diseases such as Alzheimer's and multiple sclerosis. Targeting stages of disease and associated mechanisms will be critical.

  1. White Matter Lipids as a Ketogenic Fuel Supply in Aging Female Brain: Implications for Alzheimer's Disease

    PubMed Central

    Klosinski, Lauren P.; Yao, Jia; Yin, Fei; Fonteh, Alfred N.; Harrington, Michael G.; Christensen, Trace A.; Trushina, Eugenia; Brinton, Roberta Diaz

    2015-01-01

    White matter degeneration is a pathological hallmark of neurodegenerative diseases including Alzheimer's. Age remains the greatest risk factor for Alzheimer's and the prevalence of age-related late onset Alzheimer's is greatest in females. We investigated mechanisms underlying white matter degeneration in an animal model consistent with the sex at greatest Alzheimer's risk. Results of these analyses demonstrated decline in mitochondrial respiration, increased mitochondrial hydrogen peroxide production and cytosolic-phospholipase-A2 sphingomyelinase pathway activation during female brain aging. Electron microscopic and lipidomic analyses confirmed myelin degeneration. An increase in fatty acids and mitochondrial fatty acid metabolism machinery was coincident with a rise in brain ketone bodies and decline in plasma ketone bodies. This mechanistic pathway and its chronologically phased activation, links mitochondrial dysfunction early in aging with later age development of white matter degeneration. The catabolism of myelin lipids to generate ketone bodies can be viewed as a systems level adaptive response to address brain fuel and energy demand. Elucidation of the initiating factors and the mechanistic pathway leading to white matter catabolism in the aging female brain provides potential therapeutic targets to prevent and treat demyelinating diseases such as Alzheimer's and multiple sclerosis. Targeting stages of disease and associated mechanisms will be critical. PMID:26844268

  2. Alzheimer's disease.

    PubMed

    De-Paula, Vanessa J; Radanovic, Marcia; Diniz, Breno S; Forlenza, Orestes V

    2012-01-01

    Alzheimer's disease (AD) is a chronic neurodegenerative disease with well-defined pathophysiological mechanisms, mostly affecting medial temporal lobe and associative neocortical structures. Neuritic plaques and neurofibrillary tangles represent the pathological hallmarks of AD, and are respectively related to the accumulation of the amyloid-beta peptide (Aβ) in brain tissues, and to cytoskeletal changes that arise from the hyperphosphorylation of microtubule-associated Tau protein in neurons. According to the amyloid hypothesis of AD, the overproduction of Aβ is a consequence of the disruption of homeostatic processes that regulate the proteolytic cleavage of the amyloid precursor protein (APP). Genetic, age-related and environmental factors contribute to a metabolic shift favoring the amyloidogenic processing of APP in detriment of the physiological, secretory pathway. Aβ peptides are generated by the successive cleavage of APP by beta-secretase (BACE-1) and gamma-secretase, which has been recently characterized as part of the presenilin complex. Among several beta-amyloid isoforms that bear subtle differences depending on the number of C-terminal amino acids, Aβ (1-42) plays a pivotal role in the pathogenesis of AD. The neurotoxic potential of the Aβ peptide results from its biochemical properties that favor aggregation into insoluble oligomers and protofibrils. These further originate fibrillary Aβ species that accumulate into senile and neuritic plaques. These processes, along with a reduction of Aβ clearance from the brain, leads to the extracellular accumulation of Aβ, and the subsequent activation of neurotoxic cascades that ultimately lead to cytoskeletal changes, neuronal dysfunction and cellular death. Intracerebral amyloidosis develops in AD patients in an age-dependent manner, but recent evidence indicate that it may be observed in some subjects as early as in the third or fourth decades of life, with increasing magnitude in late middle age

  3. Commentary on "Alzheimer's Disease Drug Development and the Problem of the Blood-Brain Barrier".

    PubMed

    Simpkins, James W

    2009-09-01

    The perspective by Dr. William Pardridge entitled "Alzheimer's Disease Drug Discovery and the Problem of the Blood-Brain Barrier" makes a strong case for the imbalance in resource distribution to the drug-discovery and brain drug delivery processes, where the latter received less than 1% of the investment of the former. My own calculations are consistent with this striking imbalance. Dr. Pardridge predicts that current trials of passive immunity against beta-amyloid peptide will likely fail, whereas past trials of active immunization exhibited trial-ending side effects, in part because of disruption of the integrity of the blood-brain barrier. To bring an assessment of the physiology of the blood-brain barrier and the brain delivery of drugs to the fore, several changes are needed in the way we perceive the problem, train our young scientists, organize research efforts, and incentivize reaching our common goals of effective drug therapy for Alzheimer's disease. PMID:19751923

  4. Neuroimaging and genetic risk for Alzheimer's disease and addiction-related degenerative brain disorders.

    PubMed

    Roussotte, Florence F; Daianu, Madelaine; Jahanshad, Neda; Leonardo, Cassandra D; Thompson, Paul M

    2014-06-01

    Neuroimaging offers a powerful means to assess the trajectory of brain degeneration in a variety of disorders, including Alzheimer's disease (AD). Here we describe how multi-modal imaging can be used to study the changing brain during the different stages of AD. We integrate findings from a range of studies using magnetic resonance imaging (MRI), positron emission tomography (PET), functional MRI (fMRI) and diffusion weighted imaging (DWI). Neuroimaging reveals how risk genes for degenerative disorders affect the brain, including several recently discovered genetic variants that may disrupt brain connectivity. We review some recent neuroimaging studies of genetic polymorphisms associated with increased risk for late-onset Alzheimer's disease (LOAD). Some genetic variants that increase risk for drug addiction may overlap with those associated with degenerative brain disorders. These common associations offer new insight into mechanisms underlying neurodegeneration and addictive behaviors, and may offer new leads for treating them before severe and irreversible neurological symptoms appear.

  5. A protein homeostasis signature in healthy brains recapitulates tissue vulnerability to Alzheimer's disease.

    PubMed

    Freer, Rosie; Sormanni, Pietro; Vecchi, Giulia; Ciryam, Prajwal; Dobson, Christopher M; Vendruscolo, Michele

    2016-08-01

    In Alzheimer's disease, aggregates of Aβ and tau in amyloid plaques and neurofibrillary tangles spread progressively across brain tissues following a characteristic pattern, implying a tissue-specific vulnerability to the disease. We report a transcriptional analysis of healthy brains and identify an expression signature that predicts-at ages well before the typical onset-the tissue-specific progression of the disease. We obtain this result by finding a quantitative correlation between the histopathological staging of the disease and the expression patterns of the proteins that coaggregate in amyloid plaques and neurofibrillary tangles, together with those of the protein homeostasis components that regulate Aβ and tau. Because this expression signature is evident in healthy brains, our analysis provides an explanatory link between a tissue-specific environmental risk of protein aggregation and a corresponding vulnerability to Alzheimer's disease. PMID:27532054

  6. Focally Elevated Creatine Detected in Amyloid Precursor Protein (APP) Transgenic Mice and Alzheimer Disease Brain Tissue

    SciTech Connect

    Gallant,M.; Rak, M.; Szeghalmi, A.; Del Bigio, M.; Westaway, D.; Yang, J.; Julian, R.; Gough, K.

    2006-01-01

    The creatine/phosphocreatine system, regulated by creatine kinase, plays an important role in maintaining energy balance in the brain. Energy metabolism and the function of creatine kinase are known to be affected in Alzheimer diseased brain and in cells exposed to the {beta}-amyloid peptide. We used infrared microspectroscopy to examine hippocampal, cortical, and caudal tissue from 21-89-week-old transgenic mice expressing doubly mutant (K670N/M671L and V717F) amyloid precursor protein and displaying robust pathology from an early age. Microcrystalline deposits of creatine, suggestive of perturbed energetic status, were detected by infrared microspectroscopy in all animals with advanced plaque pathology. Relatively large creatine deposits were also found in hippocampal sections from post-mortem Alzheimer diseased human brain, compared with hippocampus from non-demented brain. We therefore speculate that this molecule is a marker of the disease process.

  7. Clock Drawing Performance and Brain Morphology in Mild Cognitive Impairment and Alzheimer's Disease

    ERIC Educational Resources Information Center

    Thomann, Philipp A.; Toro, Pablo; Santos, Vasco Dos; Essig, Marco; Schroder, Johannes

    2008-01-01

    The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive…

  8. Microprobe PIXE analysis of aluminium in the brains of patients with Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Yumoto, S.; Horino, Y.; Mokuno, Y.; Kakimi, S.; Fujii, K.

    1996-04-01

    To investigate the cause of Alzheimer's disease (senile dementia), we examined aluminium (Al) in the rat liver, and in the brains (hippocampus) of Alzheimer's disease patients using heavy ion (5 MeV Si 3+) microprobe and proton (2 MeV) microprobe PIXE analysis. Heavy ion microprobes (3 MeV Si 2+) have several time's higher sensitivity for Al detection than 2 MeV proton microprobes. (1) In the rat liver, Al was detected in the cell nuclei, where phosphorus (P) was most densely distributed. (2) We also demonstrated Al in the cell nuclei isolated from Alzheimer's disease brains using heavy ion (5 MeV Si 3+) microprobes. Al spectra were detected using 2 MeV proton microprobes in the isolated brain cell nuclei. Al could not be observed in areas where P was present in relatively small amounts, or was absent. Our results indicate that Alzheimer's disease is caused by irreversible accumulation of Al in the nuclei of brain cells.

  9. Repurposing diabetes drugs for brain insulin resistance in Alzheimer disease.

    PubMed

    Yarchoan, Mark; Arnold, Steven E

    2014-07-01

    A growing body of clinical and epidemiological research suggests that two of the most common diseases of aging, type 2 diabetes (T2DM) and Alzheimer disease (AD), are linked. The nature of the association is not known, but this observation has led to the notion that drugs developed for the treatment of T2DM may be beneficial in modifying the pathophysiology of AD and maintaining cognitive function. Recent advances in the understanding of the biology of T2DM have resulted in a growing number of therapies that are approved or in clinical development for this disease. This review summarizes the evidence that T2DM and AD are linked, with a focus on the cellular and molecular mechanisms in common, and then assesses the various clinical-stage diabetes drugs for their potential activity in AD. At a time when existing therapies for AD offer only limited symptomatic benefit for some patients, additional clinical trials of diabetes drugs are needed to at least advance the care of T2DM patients at risk for or with comorbid AD and also to determine their value for AD in general.

  10. Synchrotron FTIR microspectroscopy of Alzheimer's diseased brain tissue at the SRC beamline

    NASA Astrophysics Data System (ADS)

    Bromberg, Pam S.; Gough, Kathleen M.; Ogg, Mandy; Del Bigio, M. R.; Julian, Robert

    1999-10-01

    Alzheimer's Disease is a neurodegenerative disorder marked by progressive cognitive decline. AD presents with many of the same clinical symptoms as senile dementia, but the diagnosis of AD must be confirmed by post-mortem examination of the morphological and histopathological features of the brain. The two classical lesions found in the cortical and hippocampal regions of the brain are the (beta) -amyloid- bearing neuritic plaques and the intraneuronal neurofibrillary tangles.

  11. Increased acetyl and total histone levels in post-mortem Alzheimer's disease brain.

    PubMed

    Narayan, Pritika J; Lill, Claire; Faull, Richard; Curtis, Maurice A; Dragunow, Mike

    2015-02-01

    Histone acetylation is an epigenetic modification that plays a critical role in chromatin remodelling and transcriptional regulation. There is increasing evidence that epigenetic modifications may become compromised in aging and increase susceptibility to the development of neurodegenerative disorders such as Alzheimer's disease. Immunohistochemical labelling of free-floating sections from the inferior temporal gyrus (Alzheimer's disease, n=14; control, n=17) and paraffin-embedded tissue microarrays containing tissue from the middle temporal gyrus (Alzheimer's disease, n=29; control, n=28) demonstrated that acetyl histone H3 and acetyl histone H4 levels, as well as total histone H3 and total histone H4 protein levels, were significantly increased in post-mortem Alzheimer's disease brain tissue compared to age- and sex-matched neurologically normal control brain tissue. Changes in acetyl histone levels were proportional to changes in total histone levels. The increase in acetyl histone H3 and H4 was observed in Neuronal N immunopositive pyramidal neurons in Alzheimer's disease brain. Using immunolabelling, histone markers correlated significantly with the level of glial fibrillary acidic protein and HLA-DP, -DQ and -DR immunopositive cells and with the pathological hallmarks of Alzheimer's disease (hyperphosphorylated tau load and β-amyloid plaques). Given that histone acetylation changes were correlated with changes in total histone protein, it was important to evaluate if protein degradation pathways may be compromised in Alzheimer's disease. Consequently, significant positive correlations were also found between ubiquitin load and histone modifications. The relationship between histone acetylation and ubiquitin levels was further investigated in an in vitro model of SK-N-SH cells treated with the proteasome inhibitor Mg132 and the histone deacetylase inhibitor valproic acid. In this model, compromised protein degradation caused by Mg132 lead to elevated histone

  12. The balance between cognitive reserve and brain imaging biomarkers of cerebrovascular and Alzheimer's diseases.

    PubMed

    Murray, Alison D; Staff, Roger T; McNeil, Christopher J; Salarirad, Sima; Ahearn, Trevor S; Mustafa, Nazahah; Whalley, Lawrence J

    2011-12-01

    The cognitive reserve hypothesis explains the disparity between clinical and pathological phenotypes and why, in two individuals with the same extent of neuropathology, one may be demented while the other remains cognitively intact. We examined the balance between brain magnetic resonance imaging measures of the two most common pathologies associated with brain ageing, cerebrovascular disease and Alzheimer's disease, and parameters of cerebral reserve in well-characterized participants born in 1936, for whom childhood intelligence is known. Brain magnetic resonance imaging was carried out at 1.5T using fluid attenuation inversion recovery and T(1)-weighted volumetric sequences in 249 participants. Cerebrovascular disease was quantified by measuring brain white matter hyperintensities on fluid attenuation inversion recovery images using Scheltens' scale and Alzheimer's disease was measured from volumetric data using FreeSurfer to extract whole brain volume and hippocampal volumes in turn. The effect of these measures of brain burden on life-long cognitive ageing from the age of 11 to 68 years was compared with the effect of educational attainment and occupational grade using structural equation modelling. Complete brain burden and reserve data were available in 224 participants. We found that educational attainment, but not occupation, has a measurable and positive effect, with a standardized regression weight of +0.23, on late life cognitive ability in people without cognitive impairment aged 68 years, allowing for the influence of childhood intelligence and the two most common subclinical brain pathological burdens in the ageing brain. In addition, we demonstrate that the magnitude of the contribution of education is greater than the negative impact of either neuropathological burden alone, with standardized regression weights of -0.14 for white matter hyperintensities and -0.20 for hippocampal atrophy. This study illustrates how education counteracts the

  13. Treatments for Alzheimer's Disease

    MedlinePlus

    ... 3900 Find your chapter: search by state Home > Alzheimer's Disease > Treatments Overview What Is Dementia? What Is Alzheimer's? ... and move closer to a cure. Treatments for Alzheimer's disease Currently, there is no cure for Alzheimer's. But ...

  14. Effects of BDNF Val66Met polymorphism on brain metabolism in Alzheimer's disease.

    PubMed

    Xu, Cunlu; Wang, Zhenhua; Fan, Ming; Liu, Bing; Song, Ming; Zhen, Xiantong; Jiang, Tianzi

    2010-08-23

    Earlier studies showed that the Val66Met polymorphisms of the brain-derived neurotrophic factor differentially affect gray matter volume and brain region activities. This study used resting positron emission tomography to investigate the relationship between the polymorphisms of Val66Met and the regional cerebral metabolic rate in the brain. We analyzed the positron emission tomography images of 215 patients from the Alzheimer's Disease Neuroimaging Initiative and found significant differences in the parahippocampal gyrus, superior temporal gyrus, prefrontal cortex, and inferior parietal lobule when comparing Met carriers with noncarriers among both the normal controls and those with mild cognitive impairment. For those with Alzheimer's disease, we also found additional differences in the bilateral insula between the carriers and noncarriers.

  15. Insulin-resistant brain state: the culprit in sporadic Alzheimer's disease?

    PubMed

    Correia, Sónia C; Santos, Renato X; Perry, George; Zhu, Xiongwei; Moreira, Paula I; Smith, Mark A

    2011-04-01

    Severe abnormalities in brain glucose/energy metabolism and insulin signaling have been documented to take a pivotal role in early sporadic Alzheimer's disease (sAD) pathology. Indeed, the "insulin-resistant brain state" has been hypothesized to form the core of the neurodegenerative events that occur in sAD. In this vein, intracerebroventricular administration of subdiabetogenic doses of streptozotocin (STZ) in rats can induce an insulin-resistant brain state, which is proposed as a suitable experimental model of sAD. This review highlights the involvement of disturbed brain insulin metabolism in sAD etiopathogenesis. Furthermore, current knowledge demonstrates that central STZ administration produces brain pathology and behavioral changes that resemble changes found in sAD patients. The STZ-intracerebroventricularly treated rat represents a promising experimental tool in this field by providing new insights concerning early brain alterations in sAD, which can be translated in novel etiopathogenic and therapeutic approaches in this disease.

  16. Neuropathology of Alzheimer's disease.

    PubMed

    Perl, Daniel P

    2010-01-01

    Alois Alzheimer first pointed out that the disease which would later bear his name has a distinct and recognizable neuropathological substrate. Since then, much has been added to our understanding of the pathological lesions associated with the condition. The 2 primary cardinal lesions associated with Alzheimer's disease are the neurofibrillary tangle and the senile plaque. The neurofibrillary tangle consists of abnormal accumulations of abnormally phosphorylated tau within the perikaryal cytoplasm of certain neurons. The senile plaque consists of a central core of beta-amyloid, a 4-kD peptide, surrounded by abnormally configured neuronal processes or neurites. Other neuropathological lesions are encountered in cases of Alzheimer's disease, but the disease is defined and recognized by these 2 cardinal lesions. Other lesions include poorly understood changes such as granulovacuolar degeneration and eosinophilic rodlike bodies (Hirano bodies). The loss of synaptic components is a change that clearly has a significant impact on cognitive function and represents another important morphological alteration. It is important to recognize that distinguishing between Alzheimer's disease, especially in its early stages, and normal aging may be very difficult, particularly if one is examining the brains of patients who died at an advanced old age. It is also noted that instances of pure forms of Alzheimer's disease, in the absence of other coexistent brain disease processes, such as infarctions or Parkinson's disease-related lesions, are relatively uncommon, and this must be taken into account by researchers who employ postmortem brain tissues for research.

  17. CYP46A1 inhibition, brain cholesterol accumulation and neurodegeneration pave the way for Alzheimer's disease.

    PubMed

    Djelti, Fathia; Braudeau, Jerome; Hudry, Eloise; Dhenain, Marc; Varin, Jennifer; Bièche, Ivan; Marquer, Catherine; Chali, Farah; Ayciriex, Sophie; Auzeil, Nicolas; Alves, Sandro; Langui, Dominique; Potier, Marie-Claude; Laprevote, Olivier; Vidaud, Michel; Duyckaerts, Charles; Miles, Richard; Aubourg, Patrick; Cartier, Nathalie

    2015-08-01

    Abnormalities in neuronal cholesterol homeostasis have been suspected or observed in several neurodegenerative disorders including Alzheimer's disease, Parkinson's disease and Huntington's disease. However, it has not been demonstrated whether an increased abundance of cholesterol in neurons in vivo contributes to neurodegeneration. To address this issue, we used RNA interference methodology to inhibit the expression of cholesterol 24-hydroxylase, encoded by the Cyp46a1 gene, in the hippocampus of normal mice. Cholesterol 24-hydroxylase controls cholesterol efflux from the brain and thereby plays a major role in regulating brain cholesterol homeostasis. We used an adeno-associated virus vector encoding short hairpin RNA directed against the mouse Cyp46a1 mRNA to decrease the expression of the Cyp46a1 gene in hippocampal neurons of normal mice. This increased the cholesterol concentration in neurons, followed by cognitive deficits and hippocampal atrophy due to apoptotic neuronal death. Prior to neuronal death, the recruitment of the amyloid protein precursor to lipid rafts was enhanced leading to the production of β-C-terminal fragment and amyloid-β peptides. Abnormal phosphorylation of tau and endoplasmic reticulum stress were also observed. In the APP23 mouse model of Alzheimer's disease, the abundance of amyloid-β peptides increased following inhibition of Cyp46a1 expression, and neuronal death was more widespread than in normal mice. Altogether, these results suggest that increased amounts of neuronal cholesterol within the brain may contribute to inducing and/or aggravating Alzheimer's disease.

  18. [Alzheimer and the discovery of Alzheimer's disease].

    PubMed

    Zhagn, Lili; Li, Zhiping

    2014-09-01

    Alzheimer was born in Germany in 1864. In 1887, Alzheimer graduated with a medical doctor degree at the University of Würzburg. In 1888, Alzheimer began to work in the Community Hospital for Mental and Epileptic Patients in Frankfurt am Main for 14 years. During this time, Alzheimer published the six-volume Histologic and Histopathologic Studies of the Cerebral Cortex, with co-author Franz Nissl. In 1903, Alzheimer came to work in the Royal Psychiatric Clinic of the University of Munich. One year later, he published his postdoctoral paper of Histological Studies about the Differential Diagnosis of Progressive Paralysis in 1904. In 1912, Alzheimer was provided the chair of psychiatry at the University of Breslau. On the way to Breslau, Alzheimer got sick, and eventually died in 1915. In 1906, Alzheimer found numerous amyloid plaques and neurofibrillary tangles in the brain of a patient called Auguste under the microscope. In November of the same year, Alzheimer gave a lecture about Auguste's case at the 37(th) Conference of South-West German Psychiatrists in Tübingen, which received little attention. In 1910, Kraepelin mentioned "Alzheimer's disease" for the first time to name the disease of what Auguste got in the 8th edition of Handbook of Psychiatry. Therefore, Alzheimer achieved worldwide recognition.

  19. [Alzheimer and the discovery of Alzheimer's disease].

    PubMed

    Zhagn, Lili; Li, Zhiping

    2014-09-01

    Alzheimer was born in Germany in 1864. In 1887, Alzheimer graduated with a medical doctor degree at the University of Würzburg. In 1888, Alzheimer began to work in the Community Hospital for Mental and Epileptic Patients in Frankfurt am Main for 14 years. During this time, Alzheimer published the six-volume Histologic and Histopathologic Studies of the Cerebral Cortex, with co-author Franz Nissl. In 1903, Alzheimer came to work in the Royal Psychiatric Clinic of the University of Munich. One year later, he published his postdoctoral paper of Histological Studies about the Differential Diagnosis of Progressive Paralysis in 1904. In 1912, Alzheimer was provided the chair of psychiatry at the University of Breslau. On the way to Breslau, Alzheimer got sick, and eventually died in 1915. In 1906, Alzheimer found numerous amyloid plaques and neurofibrillary tangles in the brain of a patient called Auguste under the microscope. In November of the same year, Alzheimer gave a lecture about Auguste's case at the 37(th) Conference of South-West German Psychiatrists in Tübingen, which received little attention. In 1910, Kraepelin mentioned "Alzheimer's disease" for the first time to name the disease of what Auguste got in the 8th edition of Handbook of Psychiatry. Therefore, Alzheimer achieved worldwide recognition. PMID:25579215

  20. Characterization and chromosomal localization of a cDNA encoding brain amyloid of Alzheimer's disease

    SciTech Connect

    Goldgaber, D.; Lerman, M.I.; McBride, O.W.; Saffiotti, U.; Gajdusek, D.C.

    1987-02-20

    Four clones were isolated from an adult human brain complementary DNA library with an oligonucleotide probe corresponding to the first 20 amino acids of the ..beta.. peptide of brain amyloid from Alzheimer's disease. The open reading frame of the sequenced clone coded for 97 amino acids, including the known amino acid sequence of this polypeptide. The 3.5-kilobase messenger RNA was detected in mammalian brains and human thymus. The gene is highly conserved in evolution and has been mapped to human chromosome 21.

  1. PIXE analysis of low concentration aluminum in brain tissues of an Alzheimer's disease patient

    SciTech Connect

    Ishihara, R.; Takeuchi, T.; Hanaichi, T.; Ektessabi, A. M.

    1999-06-10

    An excess accumulation and presence of metal ions may significantly alter a brain cell's normal functions. There have been increasing efforts in recent years to measure and quantify the density and distribution of excessive accumulations of constituent elements (such as Fe, Zn, Cu, and Ca) in the brain, as well as the presence and distribution of contaminating elements (such as Al). This is particularly important in cases of neuropathological disorders such as Alzheimer's disease, Parkinson's disease and ALS. The aim of this paper was to measure the Al present in the temporal cortex of the brain of an Alzheimer's disease patient. The specimens were taken from an unfixed autopsy brain which has been preserved for a period of 4 years in the deep freezer at -80 degree sign C. Proton Induced X-ray Emission Spectroscopy was used for the measurement of Al concentration in this brain tissue. A tandem accelerator with 2 MeV of energy was also used. In order to increase the sensitivity of the signals in the low energy region of the spectra, the absorbers were removed. The results show that the peak height depends on the measurement site. However, in certain cases an extremely high concentration of Al was observed in the PIXE spectra, with an intensity higher than those in the other major elements of the brain's matrix element. Samples from tissues affected by the same disease were analyzed using the EDX analyzer. The results are quantitatively in very good agreement with those of the PIXE analysis.

  2. Neuroinflammation in Alzheimer's disease.

    PubMed

    Heneka, Michael T; Carson, Monica J; El Khoury, Joseph; Landreth, Gary E; Brosseron, Frederic; Feinstein, Douglas L; Jacobs, Andreas H; Wyss-Coray, Tony; Vitorica, Javier; Ransohoff, Richard M; Herrup, Karl; Frautschy, Sally A; Finsen, Bente; Brown, Guy C; Verkhratsky, Alexei; Yamanaka, Koji; Koistinaho, Jari; Latz, Eicke; Halle, Annett; Petzold, Gabor C; Town, Terrence; Morgan, Dave; Shinohara, Mari L; Perry, V Hugh; Holmes, Clive; Bazan, Nicolas G; Brooks, David J; Hunot, Stéphane; Joseph, Bertrand; Deigendesch, Nikolaus; Garaschuk, Olga; Boddeke, Erik; Dinarello, Charles A; Breitner, John C; Cole, Greg M; Golenbock, Douglas T; Kummer, Markus P

    2015-04-01

    Increasing evidence suggests that Alzheimer's disease pathogenesis is not restricted to the neuronal compartment, but includes strong interactions with immunological mechanisms in the brain. Misfolded and aggregated proteins bind to pattern recognition receptors on microglia and astroglia, and trigger an innate immune response characterised by release of inflammatory mediators, which contribute to disease progression and severity. Genome-wide analysis suggests that several genes that increase the risk for sporadic Alzheimer's disease encode factors that regulate glial clearance of misfolded proteins and the inflammatory reaction. External factors, including systemic inflammation and obesity, are likely to interfere with immunological processes of the brain and further promote disease progression. Modulation of risk factors and targeting of these immune mechanisms could lead to future therapeutic or preventive strategies for Alzheimer's disease.

  3. Neuroinflammation in Alzheimer's disease.

    PubMed

    Heneka, Michael T; Carson, Monica J; El Khoury, Joseph; Landreth, Gary E; Brosseron, Frederic; Feinstein, Douglas L; Jacobs, Andreas H; Wyss-Coray, Tony; Vitorica, Javier; Ransohoff, Richard M; Herrup, Karl; Frautschy, Sally A; Finsen, Bente; Brown, Guy C; Verkhratsky, Alexei; Yamanaka, Koji; Koistinaho, Jari; Latz, Eicke; Halle, Annett; Petzold, Gabor C; Town, Terrence; Morgan, Dave; Shinohara, Mari L; Perry, V Hugh; Holmes, Clive; Bazan, Nicolas G; Brooks, David J; Hunot, Stéphane; Joseph, Bertrand; Deigendesch, Nikolaus; Garaschuk, Olga; Boddeke, Erik; Dinarello, Charles A; Breitner, John C; Cole, Greg M; Golenbock, Douglas T; Kummer, Markus P

    2015-04-01

    Increasing evidence suggests that Alzheimer's disease pathogenesis is not restricted to the neuronal compartment, but includes strong interactions with immunological mechanisms in the brain. Misfolded and aggregated proteins bind to pattern recognition receptors on microglia and astroglia, and trigger an innate immune response characterised by release of inflammatory mediators, which contribute to disease progression and severity. Genome-wide analysis suggests that several genes that increase the risk for sporadic Alzheimer's disease encode factors that regulate glial clearance of misfolded proteins and the inflammatory reaction. External factors, including systemic inflammation and obesity, are likely to interfere with immunological processes of the brain and further promote disease progression. Modulation of risk factors and targeting of these immune mechanisms could lead to future therapeutic or preventive strategies for Alzheimer's disease. PMID:25792098

  4. A culture-brain link: Negative age stereotypes predict Alzheimer's disease biomarkers.

    PubMed

    Levy, Becca R; Ferrucci, Luigi; Zonderman, Alan B; Slade, Martin D; Troncoso, Juan; Resnick, Susan M

    2016-02-01

    Although negative age stereotypes have been found to predict adverse outcomes among older individuals, it was unknown whether the influence of stereotypes extends to brain changes associated with Alzheimer's disease. To consider this possibility, we drew on dementia-free participants, in the Baltimore Longitudinal Study of Aging, whose age stereotypes were assessed decades before yearly magnetic resonance images and brain autopsies were performed. Those holding more-negative age stereotypes earlier in life had significantly steeper hippocampal-volume loss and significantly greater accumulation of neurofibrillary tangles and amyloid plaques, adjusting for relevant covariates. These findings suggest a new pathway to identifying mechanisms and potential interventions related to the pathology of Alzheimer's disease.

  5. Low brain ascorbic acid increases susceptibility to seizures in mouse models of decreased brain ascorbic acid transport and Alzheimer's disease.

    PubMed

    Warner, Timothy A; Kang, Jing-Qiong; Kennard, John A; Harrison, Fiona E

    2015-02-01

    Seizures are a known co-occurring symptom of Alzheimer's disease, and they can accelerate cognitive and neuropathological dysfunction. Sub-optimal vitamin C (ascorbic acid) deficiency, that is low levels that do not lead the sufferer to present with clinical signs of scurvy (e.g. lethargy, hemorrhage, hyperkeratosis), are easily obtainable with insufficient dietary intake, and may contribute to the oxidative stress environment of both Alzheimer's disease and epilepsy. The purpose of this study was to test whether mice that have diminished brain ascorbic acid in addition to carrying human Alzheimer's disease mutations in the amyloid precursor protein (APP) and presenilin 1 (PSEN1) genes, had altered electrical activity in the brain (electroencephalography; EEG), and were more susceptible to pharmacologically induced seizures. Brain ascorbic acid was decreased in APP/PSEN1 mice by crossing them with sodium vitamin C transporter 2 (SVCT2) heterozygous knockout mice. These mice have an approximately 30% decrease in brain ascorbic acid due to lower levels of SVCT2 that supplies the brain with ASC. SVCT2+/-APP/PSEN1 mice had decreased ascorbic acid and increased oxidative stress in brain, increased mortality, faster seizure onset latency following treatment with kainic acid (10 mg/kg i.p.), and more ictal events following pentylenetetrazol (50 mg/kg i.p.) treatment. Furthermore, we report the entirely novel phenomenon that ascorbic acid deficiency alone increased the severity of kainic acid- and pentylenetetrazol-induced seizures. These data suggest that avoiding ascorbic acid deficiency may be particularly important in populations at increased risk for epilepsy and seizures, such as Alzheimer's disease.

  6. Low brain ascorbic acid increases susceptibility to seizures in mouse models of decreased brain ascorbic acid transport and Alzheimer's disease.

    PubMed

    Warner, Timothy A; Kang, Jing-Qiong; Kennard, John A; Harrison, Fiona E

    2015-02-01

    Seizures are a known co-occurring symptom of Alzheimer's disease, and they can accelerate cognitive and neuropathological dysfunction. Sub-optimal vitamin C (ascorbic acid) deficiency, that is low levels that do not lead the sufferer to present with clinical signs of scurvy (e.g. lethargy, hemorrhage, hyperkeratosis), are easily obtainable with insufficient dietary intake, and may contribute to the oxidative stress environment of both Alzheimer's disease and epilepsy. The purpose of this study was to test whether mice that have diminished brain ascorbic acid in addition to carrying human Alzheimer's disease mutations in the amyloid precursor protein (APP) and presenilin 1 (PSEN1) genes, had altered electrical activity in the brain (electroencephalography; EEG), and were more susceptible to pharmacologically induced seizures. Brain ascorbic acid was decreased in APP/PSEN1 mice by crossing them with sodium vitamin C transporter 2 (SVCT2) heterozygous knockout mice. These mice have an approximately 30% decrease in brain ascorbic acid due to lower levels of SVCT2 that supplies the brain with ASC. SVCT2+/-APP/PSEN1 mice had decreased ascorbic acid and increased oxidative stress in brain, increased mortality, faster seizure onset latency following treatment with kainic acid (10 mg/kg i.p.), and more ictal events following pentylenetetrazol (50 mg/kg i.p.) treatment. Furthermore, we report the entirely novel phenomenon that ascorbic acid deficiency alone increased the severity of kainic acid- and pentylenetetrazol-induced seizures. These data suggest that avoiding ascorbic acid deficiency may be particularly important in populations at increased risk for epilepsy and seizures, such as Alzheimer's disease. PMID:25616451

  7. Useful Information on...Alzheimer's Disease.

    ERIC Educational Resources Information Center

    Cohen, Gene D.

    This brochure provides information on Alzheimer's disease by examining who gets Alzheimer's disease and what to expect when someone has Alzheimer's disease. Abnormal brain tissue findings are discussed and three clinical features of Alzheimer's disease are listed: dementia; insidious onset of symptoms; and exclusion of all other specific causes of…

  8. Brain insulin resistance in Alzheimer's disease and its potential treatment with GLP-1 analogs.

    PubMed

    Talbot, Konrad

    2014-01-01

    The prevalence of Alzheimer's disease is increasing rapidly in the absence of truly effective therapies. A promising strategy for developing such therapies is the treatment of brain insulin resistance, a common and early feature of Alzheimer's disease, closely tied to cognitive decline and capable of promoting many biological abnormalities in the disorder. The proximal cause of brain insulin resistance appears to be neuronal elevation in the serine phosphorylation of IRS-1, most likely due to amyloid-β-triggered microglial release of proinflammatory cytokines. Preclinically, the first line of defense is behavior-lowering peripheral insulin resistance (e.g., physical exercise and a Mediterranean diet supplemented with foods rich in flavonoids, curcumin and ω-3 fatty acids). More potent remediation is required, however, at clinical stages. Fortunately, the US FDA-approved antidiabetics exenatide (Byetta; Amylin Pharmaceuticals, Inc., CA, USA) and liraglutide (Victoza; Novo Nordisk A/S, Bagsvaerd, Denmark) are showing much promise in reducing Alzheimer's disease pathology and in restoring normal brain insulin responsiveness and cognitive function. PMID:24640977

  9. Discriminant analysis of intermediate brain atrophy rates in longitudinal diagnosis of alzheimer's disease

    PubMed Central

    2011-01-01

    Diagnosing Alzheimer's disease through MRI neuroimaging biomarkers has been used as a complementary marker for traditional clinical markers to improve diagnostic accuracy and also help in developing new pharmacotherapeutic trials. It has been revealed that longitudinal analysis of the whole brain atrophy has the power of discriminating Alzheimer's disease and elderly normal controls. In this work, effect of involving intermediate atrophy rates and impact of using uncorrelated principal components of these features instead of original ones on discriminating normal controls and Alzheimer's disease subjects, is inspected. In fact, linear discriminative analysis of atrophy rates is used to classify subjects into Alzheimer's disease and controls. Leave-one-out cross-validation has been adopted to evaluate the generalization rate of the classifier along with its memorization. Results show that incorporating uncorrelated version of intermediate features leads to the same memorization performance as the original ones but higher generalization rate. As a conclusion, it is revealed that in a longitudinal study, using intermediate MRI scans and transferring them to an uncorrelated feature space can improve diagnostic accuracy. PMID:22035255

  10. Effects of traumatic brain injury and posttraumatic stress disorder on Alzheimer's disease in veterans, using the Alzheimer's Disease Neuroimaging Initiative.

    PubMed

    Weiner, Michael W; Veitch, Dallas P; Hayes, Jacqueline; Neylan, Thomas; Grafman, Jordan; Aisen, Paul S; Petersen, Ronald C; Jack, Clifford; Jagust, William; Trojanowski, John Q; Shaw, Leslie M; Saykin, Andrew J; Green, Robert C; Harvey, Danielle; Toga, Arthur W; Friedl, Karl E; Pacifico, Anthony; Sheline, Yvette; Yaffe, Kristine; Mohlenoff, Brian

    2014-06-01

    Both traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) are common problems resulting from military service, and both have been associated with increased risk of cognitive decline and dementia resulting from Alzheimer's disease (AD) or other causes. This study aims to use imaging techniques and biomarker analysis to determine whether traumatic brain injury (TBI) and/or PTSD resulting from combat or other traumas increase the risk for AD and decrease cognitive reserve in Veteran subjects, after accounting for age. Using military and Department of Veterans Affairs records, 65 Vietnam War veterans with a history of moderate or severe TBI with or without PTSD, 65 with ongoing PTSD without TBI, and 65 control subjects are being enrolled in this study at 19 sites. The study aims to select subject groups that are comparable in age, gender, ethnicity, and education. Subjects with mild cognitive impairment (MCI) or dementia are being excluded. However, a new study just beginning, and similar in size, will study subjects with TBI, subjects with PTSD, and control subjects with MCI. Baseline measurements of cognition, function, blood, and cerebrospinal fluid biomarkers; magnetic resonance images (structural, diffusion tensor, and resting state blood-level oxygen dependent (BOLD) functional magnetic resonance imaging); and amyloid positron emission tomographic (PET) images with florbetapir are being obtained. One-year follow-up measurements will be collected for most of the baseline procedures, with the exception of the lumbar puncture, the PET imaging, and apolipoprotein E genotyping. To date, 19 subjects with TBI only, 46 with PTSD only, and 15 with TBI and PTSD have been recruited and referred to 13 clinics to undergo the study protocol. It is expected that cohorts will be fully recruited by October 2014. This study is a first step toward the design and statistical powering of an AD prevention trial using at-risk veterans as subjects, and provides the

  11. Upregulation of calpain activity precedes tau phosphorylation and loss of synaptic proteins in Alzheimer's disease brain.

    PubMed

    Kurbatskaya, Ksenia; Phillips, Emma C; Croft, Cara L; Dentoni, Giacomo; Hughes, Martina M; Wade, Matthew A; Al-Sarraj, Safa; Troakes, Claire; O'Neill, Michael J; Perez-Nievas, Beatriz G; Hanger, Diane P; Noble, Wendy

    2016-01-01

    Alterations in calcium homeostasis are widely reported to contribute to synaptic degeneration and neuronal loss in Alzheimer's disease. Elevated cytosolic calcium concentrations lead to activation of the calcium-sensitive cysteine protease, calpain, which has a number of substrates known to be abnormally regulated in disease. Analysis of human brain has shown that calpain activity is elevated in AD compared to controls, and that calpain-mediated proteolysis regulates the activity of important disease-associated proteins including the tau kinases cyclin-dependent kinase 5 and glycogen kinase synthase-3. Here, we sought to investigate the likely temporal association between these changes during the development of sporadic AD using Braak staged post-mortem brain. Quantification of protein amounts in these tissues showed increased activity of calpain-1 from Braak stage III onwards in comparison to controls, extending previous findings that calpain-1 is upregulated at end-stage disease, and suggesting that activation of calcium-sensitive signalling pathways are sustained from early stages of disease development. Increases in calpain-1 activity were associated with elevated activity of the endogenous calpain inhibitor, calpastatin, itself a known calpain substrate. Activation of the tau kinases, glycogen-kinase synthase-3 and cyclin-dependent kinase 5 were also found to occur in Braak stage II-III brain, and these preceded global elevations in tau phosphorylation and the loss of post-synaptic markers. In addition, we identified transient increases in total amyloid precursor protein and pre-synaptic markers in Braak stage II-III brain, that were lost by end stage Alzheimer's disease, that may be indicative of endogenous compensatory responses to the initial stages of neurodegeneration. These findings provide insight into the molecular events that underpin the progression of Alzheimer's disease, and further highlight the rationale for investigating novel treatment

  12. Upregulation of calpain activity precedes tau phosphorylation and loss of synaptic proteins in Alzheimer's disease brain.

    PubMed

    Kurbatskaya, Ksenia; Phillips, Emma C; Croft, Cara L; Dentoni, Giacomo; Hughes, Martina M; Wade, Matthew A; Al-Sarraj, Safa; Troakes, Claire; O'Neill, Michael J; Perez-Nievas, Beatriz G; Hanger, Diane P; Noble, Wendy

    2016-03-31

    Alterations in calcium homeostasis are widely reported to contribute to synaptic degeneration and neuronal loss in Alzheimer's disease. Elevated cytosolic calcium concentrations lead to activation of the calcium-sensitive cysteine protease, calpain, which has a number of substrates known to be abnormally regulated in disease. Analysis of human brain has shown that calpain activity is elevated in AD compared to controls, and that calpain-mediated proteolysis regulates the activity of important disease-associated proteins including the tau kinases cyclin-dependent kinase 5 and glycogen kinase synthase-3. Here, we sought to investigate the likely temporal association between these changes during the development of sporadic AD using Braak staged post-mortem brain. Quantification of protein amounts in these tissues showed increased activity of calpain-1 from Braak stage III onwards in comparison to controls, extending previous findings that calpain-1 is upregulated at end-stage disease, and suggesting that activation of calcium-sensitive signalling pathways are sustained from early stages of disease development. Increases in calpain-1 activity were associated with elevated activity of the endogenous calpain inhibitor, calpastatin, itself a known calpain substrate. Activation of the tau kinases, glycogen-kinase synthase-3 and cyclin-dependent kinase 5 were also found to occur in Braak stage II-III brain, and these preceded global elevations in tau phosphorylation and the loss of post-synaptic markers. In addition, we identified transient increases in total amyloid precursor protein and pre-synaptic markers in Braak stage II-III brain, that were lost by end stage Alzheimer's disease, that may be indicative of endogenous compensatory responses to the initial stages of neurodegeneration. These findings provide insight into the molecular events that underpin the progression of Alzheimer's disease, and further highlight the rationale for investigating novel treatment

  13. Amyloid tracers detect multiple binding sites in Alzheimer's disease brain tissue.

    PubMed

    Ni, Ruiqing; Gillberg, Per-Göran; Bergfors, Assar; Marutle, Amelia; Nordberg, Agneta

    2013-07-01

    Imaging fibrillar amyloid-β deposition in the human brain in vivo by positron emission tomography has improved our understanding of the time course of amyloid-β pathology in Alzheimer's disease. The most widely used amyloid-β imaging tracer so far is (11)C-Pittsburgh compound B, a thioflavin derivative but other (11)C- and (18)F-labelled amyloid-β tracers have been studied in patients with Alzheimer's disease and cognitively normal control subjects. However, it has not yet been established whether different amyloid tracers bind to identical sites on amyloid-β fibrils, offering the same ability to detect the regional amyloid-β burden in the brains. In this study, we characterized (3)H-Pittsburgh compound B binding in autopsied brain regions from 23 patients with Alzheimer's disease and 20 control subjects (aged 50 to 88 years). The binding properties of the amyloid tracers FDDNP, AV-45, AV-1 and BF-227 were also compared with those of (3)H-Pittsburgh compound B in the frontal cortices of patients with Alzheimer's disease. Saturation binding studies revealed the presence of high- and low-affinity (3)H-Pittsburgh compound B binding sites in the frontal cortex (K(d1): 3.5 ± 1.6 nM; K(d2): 133 ± 30 nM) and hippocampus (K(d1):5.6 ± 2.2 nM; K(d2): 181 ± 132 nM) of Alzheimer's disease brains. The relative proportion of high-affinity to low-affinity sites was 6:1 in the frontal cortex and 3:1 in the hippocampus. One control showed both high- and low-affinity (3)H-Pittsburgh compound B binding sites (K(d1): 1.6 nM; K(d2): 330 nM) in the cortex while the others only had a low-affinity site (K(d2): 191 ± 70 nM). (3)H-Pittsburgh compound B binding in Alzheimer's disease brains was higher in the frontal and parietal cortices than in the caudate nucleus and hippocampus, and negligible in the cerebellum. Competitive binding studies with (3)H-Pittsburgh compound B in the frontal cortices of Alzheimer's disease brains revealed high- and low-affinity binding sites for BTA

  14. Automatic detection of the hippocampal region associated with Alzheimer's disease from microscopic images of mice brain

    NASA Astrophysics Data System (ADS)

    Albaidhani, Tahseen; Hawkes, Cheryl; Jassim, Sabah; Al-Assam, Hisham

    2016-05-01

    The hippocampus is the region of the brain that is primarily associated with memory and spatial navigation. It is one of the first brain regions to be damaged when a person suffers from Alzheimer's disease. Recent research in this field has focussed on the assessment of damage to different blood vessels within the hippocampal region from a high throughput brain microscopic images. The ultimate aim of our research is the creation of an automatic system to count and classify different blood vessels such as capillaries, veins, and arteries in the hippocampus region. This work should provide biologists with efficient and accurate tools in their investigation of the causes of Alzheimer's disease. Locating the boundary of the Region of Interest in the hippocampus from microscopic images of mice brain is the first essential stage towards developing such a system. This task benefits from the variation in colour channels and texture between the two sides of the hippocampus and the boundary region. Accordingly, the developed initial step of our research to locating the hippocampus edge uses a colour-based segmentation of the brain image followed by Hough transforms on the colour channel that isolate the hippocampus region. The output is then used to split the brain image into two sides of the detected section of the boundary: the inside region and the outside region. Experimental results on a sufficiently number of microscopic images demonstrate the effectiveness of the developed solution.

  15. Aggregate-Depleted Brain Fails to Induce Aβ Deposition in a Mouse Model of Alzheimer's Disease

    PubMed Central

    Duran-Aniotz, Claudia; Morales, Rodrigo; Moreno-Gonzalez, Ines; Hu, Ping Ping; Fedynyshyn, Joseph; Soto, Claudio

    2014-01-01

    Recent studies in animal models of Alzheimer's disease (AD) show that amyloid-beta (Aβ) misfolding can be transmissible; however, the mechanisms by which this process occurs have not been fully explored. The goal of this study was to analyze whether depletion of aggregates from an AD brain suppresses its in vivo “seeding” capability. Removal of aggregates was performed by using the Aggregate Specific Reagent 1 (ASR1) compound which has been previously described to specifically bind misfolded species. Our results show that pre-treatment with ASR1-coupled magnetic beads reduces the in vivo misfolding inducing capability of an AD brain extract. These findings shed light respect to the active principle responsible for the prion-like spreading of Alzheimer's amyloid pathology and open the possibility of using seeds-capturing reagents as a promising target for AD treatment. PMID:24533166

  16. Aluminosilicates and the ageing brain: implications for the pathogenesis of Alzheimer's disease.

    PubMed

    Edwardson, J A; Klinowski, J; Oakley, A E; Perry, R H; Candy, J M

    1986-01-01

    Senile plaques are a neuropathological feature of the ageing brain and consist of abnormal neuritic and glial processes surrounding an extracellular core of material with fibrillary ultrastructure. Present at low densities in the cerebral cortex of most aged individuals, they occur in large numbers in Alzheimer's disease, the major form of senile dementia. Energy-dispersive X-ray microprobe analysis of isolated cores and plaques in situ from patients with Alzheimer's disease or Down's syndrome and from normal controls has shown co-localization of high concentrations of aluminium (4-19%) and silicon (6-24%) at the centre of the core. The presence of these elements as aluminosilicates has been confirmed using solid-state 27Al nuclear magnetic resonance. These findings provide a link with the other major neuropathological feature of Alzheimer's disease, the neurofibrillary tangle-bearing neurons, where high intracellular levels of Al and Si have also been reported. The focal deposition of these elements may be an early and essential factor in the pathogenesis of Alzheimer-type changes, reflecting an increased exposure to aluminium.

  17. Alpha1-antichymotrypsin, an inflammatory protein overexpressed in Alzheimer's disease brain, induces tau phosphorylation in neurons.

    PubMed

    Padmanabhan, Jaya; Levy, Monique; Dickson, Dennis W; Potter, Huntington

    2006-11-01

    Amyloid plaques and neurofibrillary tangles are key pathological features of Alzheimer's disease. Alzheimer's disease pathology is also characterized by neuroinflammation and neuronal degeneration, with the proteins associated with inflammatory responses being found in tight association with the plaques. One such protein is the serine protease inhibitor alpha-1-antichymotrypsin (ACT). ACT has been shown to promote Abeta polymerization in vitro and in vivo, and levels of ACT protein in plasma and cerebrospinal fluid from Alzheimer's patients have been found to correlate with progression of dementia. Here we investigated the possible involvement of ACT in tau phosphorylation and tangle formation. As was previously found for Alzheimer's disease, brains from patients with non-Alzheimer's tauopathies exhibited an enhanced expression of ACT, which correlated with the level of tau hyperphosphorylation. Transgenic mice expressing human ACT alone or ACT along with mutant human amyloid precursor protein (APP) showed a significant increase in tau phosphorylation, suggesting that this inflammatory protein can induce tau hyperphosphorylation. The increase in phosphorylation was observed at PHF-1 (P-Ser396/P-Thr404), P-Ser202 and P-Thr231 sites on tau, the P-tau epitopes that are associated with tangles in the patients. This result was further confirmed by the finding that addition of purified ACT induced the same Alzheimer's disease-related tau hyperphosphorylation in cortical neurons cultured in vitro. This correlated with an increase in extracellular signal regulated kinase (ERK) and glycogen synthase kinase-3 activation, indicating their involvement in ACT-induced tau phosphorylation. The ACT-treated neurons showed neurite loss and subsequently underwent apoptosis. Approximately 40-50% of neurons were TUNEL positive by 6 and at 24 h >70% of the neurons showed staining suggesting that ACT was inducing apoptosis in these neurons. These findings indicate that inappropriate

  18. Alzheimer's Disease Detection in Brain Magnetic Resonance Images Using Multiscale Fractal Analysis

    PubMed Central

    Lahmiri, Salim; Boukadoum, Mounir

    2013-01-01

    We present a new automated system for the detection of brain magnetic resonance images (MRI) affected by Alzheimer's disease (AD). The MRI is analyzed by means of multiscale analysis (MSA) to obtain its fractals at six different scales. The extracted fractals are used as features to differentiate healthy brain MRI from those of AD by a support vector machine (SVM) classifier. The result of classifying 93 brain MRIs consisting of 51 images of healthy brains and 42 of brains affected by AD, using leave-one-out cross-validation method, yielded 99.18% ± 0.01 classification accuracy, 100% sensitivity, and 98.20% ± 0.02 specificity. These results and a processing time of 5.64 seconds indicate that the proposed approach may be an efficient diagnostic aid for radiologists in the screening for AD. PMID:24967286

  19. Should Alzheimer's disease be equated with human brain ageing? A maladaptive interaction between brain evolution and senescence.

    PubMed

    Neill, David

    2012-01-01

    In this review Alzheimer's disease is seen as a maladaptive interaction between human brain evolution and senescence. It is predicted to occur in everyone although does not necessarily lead to dementia. The pathological process is initiated in relation to a senescence mediated functional down-regulation in the posteromedial cortex (Initiation Phase). This leads to a loss of glutamatergic excitatory input to layer II entorhinal cortex neurons. A human specific maladaptive neuroplastic response is initiated in these neurons leading to neuronal dysfunction, NFT formation and death. This leads to further loss of glutamatergic excitatory input and propagation of the maladaptive response along excitatory pathways linking evolutionary progressed vulnerable neurons (Propagation Phase). Eventually neurons are affected in many brain areas resulting in dementia. Possible therapeutic approaches include enhancing glutamatergic transmission. The theory may have implications with regards to how Alzheimer's disease is classified.

  20. Brain plasmin enhances APP alpha-cleavage and Abeta degradation and is reduced in Alzheimer's disease brains.

    PubMed

    Ledesma, M D; Da Silva, J S; Crassaerts, K; Delacourte, A; De Strooper, B; Dotti, C G

    2000-12-01

    The proteolytic processing of amyloid precursor protein (APP) has been linked to sphingolipid-cholesterol microdomains (rafts). However, the raft proteases that may be involved in APP cleavage have not yet been identified. In this work we present evidence that the protease plasmin is restricted to rafts of cultured hippocampal neurons. We also show that plasmin increases the processing of human APP preferentially at the alpha-cleavage site, and efficiently degrades secreted amyloidogenic and non-amyloidogenic APP fragments. These results suggest that brain plasmin plays a preventive role in APP amyloidogenesis. Consistently, we show that brain tissue from Alzheimer's disease patients contains reduced levels of plasmin, implying that plasmin downregulation may cause amyloid plaque deposition accompanying sporadic Alzheimer's disease.

  1. DNA methylation of Alzheimer disease and tauopathy-related genes in postmortem brain.

    PubMed

    Barrachina, Marta; Ferrer, Isidre

    2009-08-01

    DNA methylation occurs predominantly at cytosines that precede guanines in dinucleotide CpG sites; it is one of the most important mechanisms for epigenetic DNA regulation during normal development and for aberrant DNA in cancer. To determine the feasibility of DNA methylation studies in the postmortem human brain, we evaluated brain samples with variable postmortem artificially increased delays up to 48 hours. DNA methylation was analyzed in selected regions of MAPT, APP, and PSEN1 in the frontal cortex and hippocampus of controls (n=26) and those with Alzheimer disease at Stages I to II (n=17); Alzheimer disease at Stages III to IV (n=15); Alzheimer disease at Stages V to VI (n=12); argyrophilic grain disease (n=10); frontotemporal lobar degeneration linked to tau mutations (n=6); frontotemporal lobar degeneration with ubiquitin-immunoreactive inclusions (n=4); frontotemporal lobar degeneration with motor neuron disease (n=3); Pick disease (n=3); Parkinson disease (n=8); dementia with Lewy bodies, pure form (n=5); and dementia with Lewy bodies, common form (n=15). UCHL1 (ubiquitin carboxyl-terminal hydrolase 1 gene) was analyzed in the frontal cortex of controls and those with Parkinson disease and related synucleinopathies. DNA methylation sites were very reproducible in every case. No differences in the percentage of CpG methylation were found between control and disease samples or among the different pathological entities in any region analyzed. Because small changes in methylation of DNA promoters in vulnerable cells might have not been detected in total homogenates, however, these results should be interpreted with caution, particularly as they relate to chronic degenerative diseases in which small modifications may be sufficient to modulate disease progression.

  2. Inside the Brain: Unraveling the Mystery of Alzheimer's Disease

    MedlinePlus Videos and Cool Tools

    ... decisions. Inside a normal healthy brain, billions of cells called neurons constantly communicate with one another. They ... Plaques form when specific proteins in the neuron's cell membrane are processed differently. Normally, an enzyme called ...

  3. Increased brain iron coincides with early plaque formation in a mouse model of Alzheimer's disease

    SciTech Connect

    Leskovjan, A.C.; Miller, L.; Kretlow, A.; Lanzirotti, A.; Barrea,R.; Vogt, S.

    2010-11-23

    Elevated brain iron content, which has been observed in late-stage human Alzheimer's disease, is a potential target for early diagnosis. However, the time course for iron accumulation is currently unclear. Using the PSAPP mouse model of amyloid plaque formation, we conducted a time course study of metal ion content and distribution [iron (Fe), copper (Cu), and zinc (Zn)] in the cortex and hippocampus using X-ray fluorescence microscopy (XFM). We found that iron in the cortex was 34% higher than age-matched controls at an early stage, corresponding to the commencement of plaque formation. The elevated iron was not associated with the amyloid plaques. Interestingly, none of the metal ions were elevated in the amyloid plaques until the latest time point (56 weeks), where only the Zn content was significantly elevated by 38%. Since neuropathological changes in human Alzheimer's disease are presumed to occur years before the first cognitive symptoms appear, quantification of brain iron content could be a powerful marker for early diagnosis of Alzheimer's disease.

  4. Expression and distribution of carboxypeptidase B in the hippocampal subregions of normal and Alzheimer's disease brain.

    PubMed

    Papp, Henrietta; Török, I; Matsumoto, A; Enomoto, T; Matsuyama, S; Kása, P

    2003-01-01

    Earlier neurochemical studies suggested that human brain carboxypeptidase B may play a significant role in the degradation of amyloid-beta1-42 in the brain. Using an immimohistochemical technique we report here on the neuronal expression and distribution of this enzyme in the segments (CA1a, CA1b and CA1c) of the CA1 subfield and in area CA4 of the hippocampus in normal and Alzheimer's disease brain samples. Its distribution was compared with the appearance of neurofibrillary tangles in the same brain sample. For immunohistochemical localization of carboxypeptidase B, a specific C14-module antibody was applied, together with the Gallyas silver impregnation technique for the demonstration of neurofibrillary tangles. The results revealed that, in the control samples, most of the immunoreactivity appeared in segment CA1a in the pyramidal cells, less in segment CA1b and least in segment CA1c. In the Alzheimer's disease samples, there was no particular immunostaining in the neurons, but, a large number of silver-impregnated degenerated neurons appeared. The results support the suggestion that carboxypeptidase B may play a significant role in elimination of the intracellular accumulation and toxicity of amyloid-beta in the human brain and thereby protect the neurons from degeneration. PMID:12705322

  5. Prediabetes and Alzheimer's Disease

    PubMed Central

    Bitra, V. R.; Rapaka, Deepthi; Akula, Annapurna

    2015-01-01

    Aging patients with diabetes are at higher risk of developing Alzheimer's disease. Emerging evidences demonstrate the role of brain insulin resistance, which is a key mediator in prediabetes and diabetes mellitus that may lead to Alzheimer's disease. Insulin and insulin-like growth factors regulate many biological processes such as axonal growth, protein synthesis, cell growth, gene expression, proliferation, differentiation, and development. Among these, the energy metabolism and synaptic plasticity are the major transduction processes regulated by insulin, which are the core objectives for learning and memory. It was also proposed that hyper insulinemia induced insulin resistance results in injury to the central nervous system by the activation of glycogen synthase kinase 3β which is the key ailment in the cognitive decline. Hence, the endogenous brain specific insulin impairments and signaling account for the majority of Alzheimer's abnormalities. PMID:26798163

  6. Increased selenoprotein P in choroid plexus and cerebrospinal fluid in Alzheimer's disease brain.

    PubMed

    Rueli, Rachel H L H; Parubrub, Arlene C; Dewing, Andrea S T; Hashimoto, Ann C; Bellinger, Miyoko T; Weeber, Edwin J; Uyehara-Lock, Jane H; White, Lon R; Berry, Marla J; Bellinger, Frederick P

    2015-01-01

    Subjects with Alzheimer's disease (AD) have elevated brain levels of the selenium transporter selenoprotein P (Sepp1). We investigated if this elevation results from increased release of Sepp1 from the choroid plexus (CP). Sepp1 is significantly increased in CP from AD brains in comparison to non-AD brains. Sepp1 localizes to the trans-Golgi network within CP epithelia, where it is processed for secretion. The cerebrospinal fluid from AD subjects also contains increased levels Sepp1 in comparison to non-AD subjects. These findings suggest that AD pathology induces increased levels of Sepp1 within CP epithelia for release into the cerebrospinal fluid to ultimately increase brain selenium.

  7. Terahertz spectroscopy of brain tissue from a mouse model of Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Shi, Lingyan; Shumyatsky, Pavel; Rodríguez-Contreras, Adrián; Alfano, Robert

    2016-01-01

    The terahertz (THz) absorption and index of refraction of brain tissues from a mouse model of Alzheimer's disease (AD) and a control wild-type (normal) mouse were compared using THz time-domain spectroscopy (THz-TDS). Three dominating absorption peaks associated to torsional-vibrational modes were observed in AD tissue, at about 1.44, 1.8, and 2.114 THz, closer to the peaks of free tryptophan molecules than in normal tissue. A possible reason is that there is more free tryptophan in AD brain tissue, while in normal brain tissue more tryptophan is attached to other molecules. Our study suggests that THz-absorption modes may be used as an AD biomarker fingerprint in brain, and that THz-TDS is a promising technique for early diagnosis of AD.

  8. Raft disorganization leads to reduced plasmin activity in Alzheimer's disease brains.

    PubMed

    Ledesma, Maria Dolores; Abad-Rodriguez, José; Galvan, Cristian; Biondi, Elisa; Navarro, Pilar; Delacourte, Andre; Dingwall, Colin; Dotti, Carlos G

    2003-12-01

    The serine protease plasmin can efficiently degrade amyloid peptide in vitro, and is found at low levels in the hippocampus of patients with Alzheimer's disease (AD). The cause of such paucity remains unknown. We show here that the levels of total brain plasminogen and plasminogen-binding molecules are normal in these brain samples, yet plasminogen membrane binding is greatly reduced. Biochemical analysis reveals that the membranes of these brains have a mild, still significant, cholesterol reduction compared to age-matched controls, and anomalous raft microdomains. This was reflected by the loss of raft-enriched proteins, including plasminogen-binding and -activating molecules. Using hippocampal neurons in culture, we demonstrate that removal of a similar amount of membrane cholesterol is sufficient to induce raft disorganization, leading to reduced plasminogen membrane binding and low plasmin activity. These results suggest that brain raft alterations may contribute to AD by rendering the plasminogen system inefficient.

  9. A Structural Parametrization of the Brain Using Hidden Markov Models-Based Paths in Alzheimer's Disease.

    PubMed

    Martinez-Murcia, Francisco J; Górriz, Juan M; Ramírez, Javier; Ortiz, Andres

    2016-11-01

    The usage of biomedical imaging in the diagnosis of dementia is increasingly widespread. A number of works explore the possibilities of computational techniques and algorithms in what is called computed aided diagnosis. Our work presents an automatic parametrization of the brain structure by means of a path generation algorithm based on hidden Markov models (HMMs). The path is traced using information of intensity and spatial orientation in each node, adapting to the structure of the brain. Each path is itself a useful way to characterize the distribution of the tissue inside the magnetic resonance imaging (MRI) image by, for example, extracting the intensity levels at each node or generating statistical information of the tissue distribution. Additionally, a further processing consisting of a modification of the grey level co-occurrence matrix (GLCM) can be used to characterize the textural changes that occur throughout the path, yielding more meaningful values that could be associated to Alzheimer's disease (AD), as well as providing a significant feature reduction. This methodology achieves moderate performance, up to 80.3% of accuracy using a single path in differential diagnosis involving Alzheimer-affected subjects versus controls belonging to the Alzheimer's disease neuroimaging initiative (ADNI).

  10. DNA methylation map of mouse and human brain identifies target genes in Alzheimer's disease.

    PubMed

    Sanchez-Mut, Jose V; Aso, Ester; Panayotis, Nicolas; Lott, Ira; Dierssen, Mara; Rabano, Alberto; Urdinguio, Rocio G; Fernandez, Agustin F; Astudillo, Aurora; Martin-Subero, Jose I; Balint, Balazs; Fraga, Mario F; Gomez, Antonio; Gurnot, Cecile; Roux, Jean-Christophe; Avila, Jesus; Hensch, Takao K; Ferrer, Isidre; Esteller, Manel

    2013-10-01

    The central nervous system has a pattern of gene expression that is closely regulated with respect to functional and anatomical regions. DNA methylation is a major regulator of transcriptional activity, and aberrations in the distribution of this epigenetic mark may be involved in many neurological disorders, such as Alzheimer's disease. Herein, we have analysed 12 distinct mouse brain regions according to their CpG 5'-end gene methylation patterns and observed their unique epigenetic landscapes. The DNA methylomes obtained from the cerebral cortex were used to identify aberrant DNA methylation changes that occurred in two mouse models of Alzheimer's disease. We were able to translate these findings to patients with Alzheimer's disease, identifying DNA methylation-associated silencing of three targets genes: thromboxane A2 receptor (TBXA2R), sorbin and SH3 domain containing 3 (SORBS3) and spectrin beta 4 (SPTBN4). These hypermethylation targets indicate that the cyclic AMP response element-binding protein (CREB) activation pathway and the axon initial segment could contribute to the disease.

  11. Aluminium exposure induces Alzheimer's disease-like histopathological alterations in mouse brain.

    PubMed

    Rodella, L F; Ricci, F; Borsani, E; Stacchiotti, A; Foglio, E; Favero, G; Rezzani, R; Mariani, C; Bianchi, R

    2008-04-01

    Aluminium (Al) is a neurotoxic metal and Al exposure may be a factor in the aetiology of various neurodegenerative diseases such as Alzheimer's disease (AD). The major pathohistological findings in the AD brain are the presence of neuritic plaques containing beta-amyloid (Abeta) which may interfere with neuronal communication. Moreover, it has been observed that GRP78, a stress-response protein induced by conditions that adversely affect endoplasmic reticulum (ER) function, is reduced in the brain of AD patients. In this study, we investigated the correlation between the expression of Abeta and GRP78 in the brain cortex of mice chronically treated with aluminium sulphate. Chronic exposure over 12 months to aluminium sulphate in drinking water resulted in deposition of Abeta similar to that seen in congophilic amyloid angiopathy (CAA) in humans and a reduction in neuronal expression of GRP78 similar to what has previously been observed in Alzheimer's disease. So, we hypothesise that chronic Al administration is responsible for oxidative cell damage that interferes with ER functions inducing Abeta accumulation and neurodegenerative damage.

  12. Traumatic Brain Injury as a Risk Factor for Alzheimer's Disease: Is Inflammatory Signaling a Key Player?

    PubMed

    Djordjevic, Jelena; Sabbir, Mohammad Golam; Albensi, Benedict C

    2016-01-01

    Traumatic brain injury (TBI) has become a significant medical and social concern within the last 30 years. TBI has acute devastating effects, and in many cases, seems to initiate long-term neurodegeneration. With advances in medical technology, many people are now surviving severe brain injuries and their long term consequences. Post trauma effects include communication problems, sensory deficits, emotional and behavioral problems, physical complications and pain, increased suicide risk, dementia, and an increased risk for chronic CNS diseases, such as Alzheimer's disease (AD). In this review, we provide an introduction to TBI and hypothesize how it may lead to neurodegenerative disease in general and AD in particular. In addition, we discuss the evidence that supports the hypothesis that TBI may lead to AD. In particular, we focus on inflammatory responses as key processes in TBI-induced secondary injury, with emphasis on nuclear factor kappa B (NF-κB) signaling. PMID:26899581

  13. Predicting Alzheimer's disease by classifying 3D-Brain MRI images using SVM and other well-defined classifiers

    NASA Astrophysics Data System (ADS)

    Matoug, S.; Abdel-Dayem, A.; Passi, K.; Gross, W.; Alqarni, M.

    2012-02-01

    Alzheimer's disease (AD) is the most common form of dementia affecting seniors age 65 and over. When AD is suspected, the diagnosis is usually confirmed with behavioural assessments and cognitive tests, often followed by a brain scan. Advanced medical imaging and pattern recognition techniques are good tools to create a learning database in the first step and to predict the class label of incoming data in order to assess the development of the disease, i.e., the conversion from prodromal stages (mild cognitive impairment) to Alzheimer's disease, which is the most critical brain disease for the senior population. Advanced medical imaging such as the volumetric MRI can detect changes in the size of brain regions due to the loss of the brain tissues. Measuring regions that atrophy during the progress of Alzheimer's disease can help neurologists in detecting and staging the disease. In the present investigation, we present a pseudo-automatic scheme that reads volumetric MRI, extracts the middle slices of the brain region, performs segmentation in order to detect the region of brain's ventricle, generates a feature vector that characterizes this region, creates an SQL database that contains the generated data, and finally classifies the images based on the extracted features. For our results, we have used the MRI data sets from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database.

  14. MicroRNAs and their therapeutic potential for human diseases: aberrant microRNA expression in Alzheimer's disease brains.

    PubMed

    Satoh, Jun-ichi

    2010-01-01

    MicroRNAs (miRNAs) are a group of small noncoding RNAs that regulate translational repression of multiple target mRNAs. The miRNAs in a whole cell regulate greater than 30% of all protein-coding genes. The vast majority of presently identified miRNAs are expressed in the brain in a spatially and temporally controlled manner. They play a key role in neuronal development, differentiation, and synaptic plasticity. However, at present, the pathological implications of deregulated miRNA expression in neurodegenerative diseases remain largely unknown. This review will briefly summarize recent studies that focus attention on aberrant miRNA expression in Alzheimer's disease brains.

  15. Regional distribution of somatostatin receptor binding and modulation of adenylyl cyclase activity in Alzheimer's disease brain.

    PubMed

    Bergström, L; Garlind, A; Nilsson, L; Alafuzoff, I; Fowler, C J; Winblad, B; Cowburn, R F

    1991-10-01

    We have previously reported a reduction in the inhibitory effect of somatostatin on adenylyl cyclase activity in the superior temporal cortex of a group of Alzheimer's disease cases, compared to a group of matched controls. In the present study, the levels of high affinity 125I-Tyr11-somatostatin-14 binding, its modulation by guanine nucleotides and the effects of somatostatin on adenylyl cyclase activity have been measured in preparations of frontal cortex, hippocampus, caudate nucleus and cerebellum from the same patient and control groups. A significant reduction in 125I-Tyr11-somatostatin-14 binding was observed in the frontal cortex, but not other regions, of the Alzheimer's disease group, compared with control values. The profiles of inhibition of specific 125I-Tyr11-somatostatin-14 binding by Gpp(NH)p were similar in all regions in both groups. No significant differences in basal, forskolin-stimulated, or somatostatin and neuropeptide Y inhibitions of adenylyl cyclase activity were found between the two groups. The pattern of change of somatostatin binding in the Alzheimer's disease cases observed in the present study differs from the reported pattern of loss of somatostatin neurons and may be secondary to the degeneration of somatostatin receptor-bearing cholinergic afferents arising from the nucleus basalis. The results of this study indicate that impaired somatostatin modulation of adenylyl cyclase is not a global phenomenon in Alzheimer's disease brain and also that there are no major disruptions of somatostatin receptor-G-protein coupling or of adenylyl cyclase catalytic activity in this disorder. PMID:1684616

  16. Training-related brain plasticity in subjects at risk of developing Alzheimer's disease.

    PubMed

    Belleville, Sylvie; Clément, Francis; Mellah, Samira; Gilbert, Brigitte; Fontaine, Francine; Gauthier, Serge

    2011-06-01

    Subjects with mild cognitive impairment are at risk of developing Alzheimer's disease. Cognitive stimulation is an emerging intervention in the field of neurology and allied sciences, having already been shown to improve cognition in subjects with mild cognitive impairment. Yet no studies have attempted to unravel the brain mechanisms that support such improvement. This study uses functional magnetic resonance imaging to measure the effect of memory training on brain activation in older adults with mild cognitive impairment and to assess whether it can reverse the brain changes associated with mild cognitive impairment. Brain activation associated with verbal encoding and retrieval was recorded twice prior to training and once after training. In subjects with mild cognitive impairment, increased activation was found after training within a large network that included the frontal, temporal and parietal areas. Healthy controls showed mostly areas of decreased activation following training. Comparison with pre-training indicated that subjects with mild cognitive impairment used a combination of specialized areas; that is, areas activated prior to training and new alternative areas activated following training. However, only activation of the right inferior parietal lobule, a new area of activation, correlated with performance. Furthermore, the differences between the brain activation patterns of subjects with mild cognitive impairment and those of healthy controls were attenuated by training in a number of brain regions. These results indicate that memory training can result in significant neural changes that are measurable with brain imaging. They also show that the brains of people with mild cognitive impairment remain highly plastic.

  17. Maternal age affects brain metabolism in adult children of mothers affected by Alzheimer's disease.

    PubMed

    Mosconi, Lisa; Tsui, Wai; Murray, John; McHugh, Pauline; Li, Yi; Williams, Schantel; Pirraglia, Elizabeth; Glodzik, Lidia; De Santi, Susan; Vallabhajosula, Shankar; de Leon, Mony J

    2012-03-01

    Cognitively normal (NL) individuals with a maternal history of late-onset Alzheimer's disease (MH) show reduced brain glucose metabolism on FDG-PET as compared to those with a paternal history (PH) and those with negative family history (NH) of Alzheimer's disease (AD). This FDG-PET study investigates whether metabolic deficits in NL MH are associated with advancing maternal age at birth. Ninety-six NL individuals with FDG-PET were examined, including 36 MH, 24 PH, and 36 NH. Regional-to-whole brain gray matter standardized FDG uptake value ratios were examined for associations with parental age across groups using automated regions-of-interest and statistical parametric mapping. Groups were comparable for clinical and neuropsychological measures. Brain metabolism in AD-vulnerable regions was lower in MH compared to NH and PH, and negatively correlated with maternal age at birth only in MH. There were no associations between paternal age and metabolism in any group. Evidence for a maternally inherited, maternal age-related mechanism provides further insight on risk factors and genetic transmission in late-onset AD.

  18. Tool use in left brain damage and Alzheimer's disease: What about function and manipulation knowledge?

    PubMed

    Jarry, Christophe; Osiurak, François; Besnard, Jérémy; Baumard, Josselin; Lesourd, Mathieu; Croisile, Bernard; Etcharry-Bouyx, Frédérique; Chauviré, Valérie; Le Gall, Didier

    2016-03-01

    Tool use disorders are usually associated with difficulties in retrieving function and manipulation knowledge. Here, we investigate tool use (Real Tool Use, RTU), function (Functional Association, FA) and manipulation knowledge (Gesture Recognition, GR) in 17 left-brain-damaged (LBD) patients and 14 AD patients (Alzheimer disease). LBD group exhibited predicted deficit on RTU but not on FA and GR while AD patients showed deficits on GR and FA with preserved tool use skills. These findings question the role played by function and manipulation knowledge in actual tool use. PMID:26765078

  19. Cerebrolysin in Alzheimer's disease.

    PubMed

    Antón Álvarez, X; Fuentes, Patricio

    2011-07-01

    Cerebrolysin is a neuropeptide preparation mimicking the action of endogenous neurotrophic factors. Positive effects of Cerebrolysin on β-amyloid- and tau-related pathologies, neuroinflammation, neurotrophic factors, oxidative stress, excitotoxicity, neurotransmission, brain metabolism, neuroplasticity, neuronal apoptosis and degeneration, neurogenesis and cognition were demonstrated in experimental conditions. These pleiotropic effects of Cerebrolysin on Alzheimer's disease-related pathogenic events are consistent with a neurotrophic-like mode of action, and seems to involve the activation of the phosphatidylinositol 3-kinase/Akt/glycogen synthase kinase-3 β intracellular signaling pathway. The clinical efficacy of Cerebrolysin in Alzheimer's disease was evaluated in several randomized, double-blind, clinical trials, showing consistent benefits on global clinical function and cognition, improvements in behavior at high doses, and minor effects on daily living activities in patients with mild to moderate Alzheimer's disease, as well as in subgroups of moderate to moderately severe patients. In addition, the clinical benefits of Cerebrolysin were largely maintained for several months after ending treatment, a finding that supports its discontinuous administration. Cerebrolysin was generally well tolerated and did not induce significant adverse events in Alzheimer's patients. Although long-term studies are needed, the data available suggest that Cerebrolysin is effective as monotherapy and constitutes a promising option for combined therapy in Alzheimer's disease.

  20. Pregnancy Zone Protein is Increased in the Alzheimer's Disease Brain and Associates with Senile Plaques.

    PubMed

    Nijholt, Diana A T; Ijsselstijn, Linda; van der Weiden, Marcel M; Zheng, Ping-Pin; Sillevis Smitt, Peter A E; Koudstaal, Peter J; Luider, Theo M; Kros, Johan M

    2015-01-01

    Increased levels of pregnancy zone protein (PZP) were found in the serum of persons who later developed Alzheimer's disease (AD) in comparison to controls who remained dementia free. We suggested that this increase is due to brain derived PZP entering the blood stream during the early phase of the disease. Here we investigate the possible involvement of PZP in human AD pathogenesis. We observed increased PZP immunoreactivity in AD postmortem brain cortex compared to non-demented controls. In the AD cortex, PZP immunoreactivity localized to microglial cells that interacted with senile plaques and was occasionally observed in neurons. Our data link the finding of elevated serum PZP levels with the characteristic AD pathology and identify PZP as a novel component in AD.

  1. [Update on Alzheimer's disease].

    PubMed

    Dubois, B

    2009-03-01

    As the general population ages, the prevalence of Alzheimer's disease increases steadily. In France, 850,000 people are affected, with an annual incidence of 165,000 new cases. It is estimated that in 2020, 1.2 million people will be concerned in France. Nearly half of these patients, about 400,000, will have moderate to severe disease. These figures, issuing from the Eurodem group and the Paquid study, are estimates but clearly forecast an increase in upcoming years. While the disease generally affects elderly subjects, it is also known to occur early, before the age of 60. Nearly 20,000 patients will have an early onset form of the disease. Alzheimer's disease is first and foremost a brain disease, with lesions starting early in life. These early onset forms raise difficult diagnostic problems since these patients' problems are often mistakenly thought to arise from psychiatric disorders and treated as such in institutions inadapted to the patients' conditions.

  2. A Systematic Investigation into Aging Related Genes in Brain and Their Relationship with Alzheimer's Disease.

    PubMed

    Meng, Guofeng; Zhong, Xiaoyan; Mei, Hongkang

    2016-01-01

    Aging, as a complex biological process, is accompanied by the accumulation of functional loses at different levels, which makes age to be the biggest risk factor to many neurological diseases. Even following decades of investigation, the process of aging is still far from being fully understood, especially at a systematic level. In this study, we identified aging related genes in brain by collecting the ones with sustained and consistent gene expression or DNA methylation changes in the aging process. Functional analysis with Gene Ontology to these genes suggested transcriptional regulators to be the most affected genes in the aging process. Transcription regulation analysis found some transcription factors, especially Specificity Protein 1 (SP1), to play important roles in regulating aging related gene expression. Module-based functional analysis indicated these genes to be associated with many well-known aging related pathways, supporting the validity of our approach to select aging related genes. Finally, we investigated the roles of aging related genes on Alzheimer's Disease (AD). We found that aging and AD related genes both involved some common pathways, which provided a possible explanation why aging made the brain more vulnerable to Alzheimer's Disease.

  3. A Systematic Investigation into Aging Related Genes in Brain and Their Relationship with Alzheimer's Disease.

    PubMed

    Meng, Guofeng; Zhong, Xiaoyan; Mei, Hongkang

    2016-01-01

    Aging, as a complex biological process, is accompanied by the accumulation of functional loses at different levels, which makes age to be the biggest risk factor to many neurological diseases. Even following decades of investigation, the process of aging is still far from being fully understood, especially at a systematic level. In this study, we identified aging related genes in brain by collecting the ones with sustained and consistent gene expression or DNA methylation changes in the aging process. Functional analysis with Gene Ontology to these genes suggested transcriptional regulators to be the most affected genes in the aging process. Transcription regulation analysis found some transcription factors, especially Specificity Protein 1 (SP1), to play important roles in regulating aging related gene expression. Module-based functional analysis indicated these genes to be associated with many well-known aging related pathways, supporting the validity of our approach to select aging related genes. Finally, we investigated the roles of aging related genes on Alzheimer's Disease (AD). We found that aging and AD related genes both involved some common pathways, which provided a possible explanation why aging made the brain more vulnerable to Alzheimer's Disease. PMID:26937969

  4. Natural distribution of environmental radon daughters in the different brain areas of an Alzheimer Disease victim

    PubMed Central

    Momčilović, Berislav; Lykken, Glenn I; Cooley, Marvin

    2006-01-01

    Background Radon is a ubiquitous noble gas in the environment and a primary source of harmful radiation exposure for humans; it decays in a cascade of daughters (RAD) by releasing the cell damaging high energy alpha particles. Results We studied natural distribution of RAD 210Po and 210Bi in the different parts of the postmortem brain of 86-year-old woman who had suffered from Alzheimer's disease (AD). A distinct brain map emerged, since RAD distribution was different among the analyzed brain areas. The highest RAD irradiation (mSv·year-1) occurred in the decreasing order of magnitude: amygdale (Amy) >> hippocampus (Hip) > temporal lobe (Tem) ~ frontal lobe (Fro) > occipital lobe (Occ) ~ parietal lobe (Par) > substantia nigra (SN) >> locus ceruleus (LC) ~ nucleus basalis (NB); generally more RAD accumulated in the proteins than lipids of gray and white (gray > white) brain matter. Amy and Hip are particularly vulnerable brain structure targets to significant RAD internal radiation damage in AD (5.98 and 1.82 mSv·year-1, respectively). Next, naturally occurring RAD radiation for Tem and Fro, then Occ and Par, and SN was an order of magnitude higher than that in LC and NB; the later was within RAD we observed previously in the healthy control brains. Conclusion Naturally occurring environmental RAD exposure may dramatically enhance AD deterioration by selectively targeting brain areas of emotions (Amy) and memory (Hip). PMID:16965619

  5. Neuroinhibitory molecules in Alzheimer's disease.

    PubMed

    Larner, A J; Keynes, R J

    2006-09-01

    Aberrant neurite growth is one of the neuropathological signatures of the Alzheimer's disease brain, both around amyloid plaques and in the cortical neuropil. Disruption of neuroinhibitory or repulsive growth and guidance signals, as well as of neurotrophic or permissive signals, may contribute to this dystrophic growth. Hence, therapeutic efforts directed exclusively at restoring neurotrophic activity are unlikely to meet with success. The molecular species responsible for neuroinhibitory effects in the Alzheimer's disease brain are beginning to be elucidated.

  6. Multistimulation group therapy in Alzheimer's disease promotes changes in brain functioning.

    PubMed

    Baglio, Francesca; Griffanti, Ludovica; Saibene, Francesca Lea; Ricci, Cristian; Alberoni, Margherita; Critelli, Raffaella; Villanelli, Fabiana; Fioravanti, Raffaella; Mantovani, Federica; D'amico, Alessandra; Cabinio, Monia; Preti, Maria Giulia; Nemni, Raffaello; Farina, Elisabetta

    2015-01-01

    Background. The growing social emergency represented by Alzheimer's disease (AD) and the lack of medical treatments able to modify the disease course have kindled the interest in nonpharmacological therapies. Objective. We introduced a novel nonpharmacological approach for people with AD (PWA) named Multidimensional Stimulation group Therapy (MST) to improve PWA condition in different disease domains: cognition, behavior, and motor functioning. Methods. Enrolling 60 PWA in a mild to moderate stage of the disease, we evaluated the efficacy of MST with a randomized-controlled study. Neuropsychological and neurobehavioral measures and functional magnetic resonance imaging (fMRI) data were considered as outcome measures. Results. The following significant intervention-related changes were observed: reduction in Neuropsychiatric Inventory scale score, improvement in language and memory subscales of Alzheimer's Disease Assessment Scale-Cognitive subscale, and increased fMRI activations in temporal brain areas, right insular cortex, and thalamus. Conclusions. Cognitive-behavioral and fMRI results support the notion that MST has significant effects in improving PWA cognitive-behavioral status by restoring neural functioning.

  7. Classification of Alzheimer's disease using regional saliency maps from brain MR volumes

    NASA Astrophysics Data System (ADS)

    Pulido, Andrea; Rueda, Andrea; Romero, Eduardo

    2013-02-01

    Accurate diagnosis of Alzheimer's disease (AD) from structural Magnetic Resonance (MR) images is difficult due to the complex alteration of patterns in brain anatomy that could indicate the presence or absence of the pathology. Currently, an effective approach that allows to interpret the disease in terms of global and local changes is not available in the clinical practice. In this paper, we propose an approach for classification of brain MR images, based on finding pathology-related patterns through the identification of regional structural changes. The approach combines a probabilistic Latent Semantic Analysis (pLSA) technique, which allows to identify image regions through latent topics inferred from the brain MR slices, with a bottom-up Graph-Based Visual Saliency (GBVS) model, which calculates maps of relevant information per region. Regional saliency maps are finally combined into a single map on each slice, obtaining a master saliency map of each brain volume. The proposed approach includes a one-to-one comparison of the saliency maps which feeds a Support Vector Machine (SVM) classifier, to group test subjects into normal or probable AD subjects. A set of 156 brain MR images from healthy (76) and pathological (80) subjects, splitted into a training set (10 non-demented and 10 demented subjects) and one testing set (136 subjects), was used to evaluate the performance of the proposed approach. Preliminary results show that the proposed method reaches a maximum classification accuracy of 87.21%.

  8. Abeta peptide immunization restores blood-brain barrier integrity in Alzheimer disease.

    PubMed

    Dickstein, Dara L; Biron, Kaan E; Ujiie, Maki; Pfeifer, Cheryl G; Jeffries, Andrew R; Jefferies, Wilfred A

    2006-03-01

    Immunization with amyloid beta (Abeta) peptides or passive immunization with antibodies against Abeta has been reported to reduce plaque burden, neuritic dystrophy, early Tau pathology, microgliosis as well as reversing learning and memory deficits. This has created a central paradox: how does vaccination in peripheral tissues reduce plaque burden in the brain? No single explanation for these phenomena has yet been presented. To reconcile these observations, we demonstrate that the integrity of the blood-brain barrier (BBB), a structural barrier between the brain and the blood, is compromised in Tg2576 Alzheimer disease (AD) model mice. We immunized Tg2576 mice with Abeta before and after the onset of AD-type neuropathology and observed that BBB permeability, amyloid burden, and microgliosis are decreased in immunized mice. It is concluded that the integrity of the BBB is disrupted in AD mice, and after Abeta immunization the immune system clears Abeta from sources in the brain as it would in peripheral organs lacking barriers. Once Abeta is removed, the integrity of the BBB is restored. The data therefore provide an intellectual framework for understanding how the immune system can clear amyloid deposits from AD brains and suggest new strategies for limiting disease progression in amyloidopathies.

  9. Altered Expression of Diabetes-Related Genes in Alzheimer's Disease Brains: The Hisayama Study

    PubMed Central

    Hokama, Masaaki; Oka, Sugako; Leon, Julio; Ninomiya, Toshiharu; Honda, Hiroyuki; Sasaki, Kensuke; Iwaki, Toru; Ohara, Tomoyuki; Sasaki, Tomio; LaFerla, Frank M.; Kiyohara, Yutaka; Nakabeppu, Yusaku

    2014-01-01

    Diabetes mellitus (DM) is considered to be a risk factor for dementia including Alzheimer's disease (AD). However, the molecular mechanism underlying this risk is not well understood. We examined gene expression profiles in postmortem human brains donated for the Hisayama study. Three-way analysis of variance of microarray data from frontal cortex, temporal cortex, and hippocampus was performed with the presence/absence of AD and vascular dementia, and sex, as factors. Comparative analyses of expression changes in the brains of AD patients and a mouse model of AD were also performed. Relevant changes in gene expression identified by microarray analysis were validated by quantitative real-time reverse-transcription polymerase chain reaction and western blotting. The hippocampi of AD brains showed the most significant alteration in gene expression profile. Genes involved in noninsulin-dependent DM and obesity were significantly altered in both AD brains and the AD mouse model, as were genes related to psychiatric disorders and AD. The alterations in the expression profiles of DM-related genes in AD brains were independent of peripheral DM-related abnormalities. These results indicate that altered expression of genes related to DM in AD brains is a result of AD pathology, which may thereby be exacerbated by peripheral insulin resistance or DM. PMID:23595620

  10. Plasma and brain fatty acid profiles in mild cognitive impairment and Alzheimer's disease.

    PubMed

    Cunnane, Stephen C; Schneider, Julie A; Tangney, Christine; Tremblay-Mercier, Jennifer; Fortier, Mélanie; Bennett, David A; Morris, Martha Clare

    2012-01-01

    Alzheimer's disease (AD) is generally associated with lower omega-3 fatty acid intake from fish but despite numerous studies, it is still unclear whether there are differences in omega-3 fatty acids in plasma or brain. In matched plasma and brain samples provided by the Memory and Aging Project, fatty acid profiles were quantified in several plasma lipid classes and in three brain cortical regions. Fatty acid data were expressed as % composition and as concentrations (mg/dL for plasma or mg/g for brain). Differences in plasma fatty acid profiles between AD, mild cognitive impairment (MCI), and those with no cognitive impairment (NCI) were most apparent in the plasma free fatty acids (lower oleic acid isomers and omega-6 fatty acids in AD) and phospholipids (lower omega-3 fatty acids in AD). In brain, % DHA was lower only in phosphatidylserine of mid-frontal cortex and superior temporal cortex in AD compared to NCI (-14% and -12%, respectively; both p < 0.05). The only significant correlation between plasma and brain fatty acids was between % DHA in plasma total lipids and % DHA in phosphatidylethanolamine of the angular gyrus, but only in the NCI group (+0.77, p < 0.05). We conclude that AD is associated with altered plasma status of both DHA and other fatty acids unrelated to DHA, and that the lipid class-dependent nature of these differences reflects a combination of differences in intake and metabolism. PMID:22466064

  11. Cell cycle proteins in brain in mild cognitive impairment: insights into progression to Alzheimer disease.

    PubMed

    Keeney, Jeriel T R; Swomley, Aaron M; Harris, Jessica L; Fiorini, Ada; Mitov, Mihail I; Perluigi, Marzia; Sultana, Rukhsana; Butterfield, D Allan

    2012-10-01

    Recent studies have demonstrated the re-emergence of cell cycle proteins in brain as patients progress from the early stages of mild cognitive impairment (MCI) into Alzheimer's disease (AD). Oxidative stress markers present in AD have also been shown to be present in MCI brain suggesting that these events occur in early stages of the disease. The levels of key cell cycle proteins, such as CDK2, CDK5, cyclin G1, and BRAC1 have all been found to be elevated in MCI brain compared to age-matched control. Further, peptidyl prolyl cis-trans isomerase (Pin1), a protein that plays an important role in regulating the activity of key proteins, such as CDK5, GSK3-β, and PP2A that are involved in both the phosphorylation state of Tau and in the cell cycle, has been found to be oxidatively modified and downregulated in both AD and MCI brain. Hyperphosphorylation of Tau then results in synapse loss and the characteristic Tau aggregation as neurofibrillary tangles, an AD hallmark. In this review, we summarized the role of cell cycle dysregulation in the progression of disease from MCI to AD. Based on the current literature, it is tempting to speculate that a combination of oxidative stress and cell cycle dysfunction conceivably leads to neurodegeneration.

  12. Bilingualism as a contributor to cognitive reserve: evidence from brain atrophy in Alzheimer's disease.

    PubMed

    Schweizer, Tom A; Ware, Jenna; Fischer, Corinne E; Craik, Fergus I M; Bialystok, Ellen

    2012-09-01

    Much of the research on delaying the onset of symptoms of Alzheimer's disease (AD) has focused on pharmacotherapy, but environmental factors have also been acknowledged to play a significant role. Bilingualism may be one factor contributing to 'cognitive reserve' (CR) and therefore to a delay in symptom onset. If bilingualism is protective, then the brains of bilinguals should show greater atrophy in relevant areas, since their enhanced CR enables them to function at a higher level than would be predicted from their level of disease. We analyzed a number of linear measurements of brain atrophy from the computed tomography (CT) scans of monolingual and bilingual patients diagnosed with probable AD who were matched on level of cognitive performance and years of education. Bilingual patients with AD exhibited substantially greater amounts of brain atrophy than monolingual patients in areas traditionally used to distinguish AD patients from healthy controls, specifically, the radial width of the temporal horn and the temporal horn ratio. Other measures of brain atrophy were comparable for the two groups. Bilingualism appears to contribute to increased CR, thereby delaying the onset of AD and requiring the presence of greater amounts of neuropathology before the disease is manifest.

  13. Glucose Metabolic Brain Networks in Early-Onset vs. Late-Onset Alzheimer's Disease

    PubMed Central

    Chung, Jinyong; Yoo, Kwangsun; Kim, Eunjoo; Na, Duk L.; Jeong, Yong

    2016-01-01

    Objective: Early-onset Alzheimer's disease (EAD) shows distinct features from late-onset Alzheimer's disease (LAD). To explore the characteristics of EAD, clinical, neuropsychological, and functional imaging studies have been conducted. However, differences between EAD and LAD are not clear, especially in terms of brain connectivity and networks. In this study, we investigated the differences in metabolic connectivity between EAD and LAD by adopting graph theory measures. Methods: We analyzed 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) images to investigate the distinct features of metabolic connectivity between EAD and LAD. Using metabolic connectivity and graph theory analysis, metabolic network differences between LAD and EAD were explored. Results: Results showed the decreased connectivity centered in the cingulate gyri and occipital regions in EAD, whereas decreased connectivity in the occipital and temporal regions as well as increased connectivity in the supplementary motor area were observed in LAD when compared with age-matched control groups. Global efficiency and clustering coefficients were decreased in EAD but not in LAD. EAD showed progressive network deterioration as a function of disease severity and clinical dementia rating (CDR) scores, mainly in terms of connectivity between the cingulate gyri and occipital regions. Global efficiency and clustering coefficients were also decreased along with disease severity. Conclusion: These results indicate that EAD and LAD have distinguished features in terms of metabolic connectivity, with EAD demonstrating more extensive and progressive deterioration. PMID:27445800

  14. Immunohistoblot analysis on whole human hemispheres from normal and Alzheimer diseased brains.

    PubMed

    Beliczai, Zsuzsa; Varszegi, Szilvia; Gulyas, Balazs; Halldin, Christer; Kasa, Peter; Gulya, Karoly

    2008-12-01

    We demonstrate the feasibility and usefulness of the histoblot immunostaining of cryosections of whole hemispheres of healthy and Alzheimer diseased (AD) human brains by localizing a neuron-specific marker, the anti-neuronal nuclei (NeuN) antigen. As expected, cortical NeuN-immunopositive regions were generally thinner and lighter in the AD brains than in the controls. The advantages of using whole hemisphere histoblots: (1) they provide a low-resolution overview/outline of the antigen distribution in a large surface area, (2) large, thick, and/or unfixed tissue sections from post-mortem samples (perhaps of inferior tissue quality) can be compared, and (3) subsequent immunohistochemistry can be performed on the tissue sections used for the histoblots. PMID:18832000

  15. Neuronal localization of amyloid beta protein precursor mRNA in normal human brain and in Alzheimer's disease.

    PubMed Central

    Goedert, M

    1987-01-01

    Clones for the amyloid beta protein precursor gene were isolated from a cDNA library prepared from the frontal cortex of a patient who had died with a histologically confirmed diagnosis of Alzheimer's disease; they were used to investigate the tissue and cellular distribution of amyloid beta protein precursor mRNA in brain tissues from control patients and from Alzheimer's disease patients. Amyloid beta protein precursor mRNA was expressed in similar amounts in all control human brain regions examined, but a reduction of the mRNA level was observed in the frontal cortex from patients with Alzheimer's disease. By in situ hybridization amyloid beta protein precursor mRNA was present in granule and pyramidal cell bodies in the hippocampal formation and in pyramidal cell bodies in the cerebral cortex. No specific labelling of glial cells or endothelial cells was found. The same qualitative distribution was observed in tissues from control patients and from patients with Alzheimer's disease. Senile plaque amyloid thus probably derives from neurones. The tissue distribution of amyloid beta protein precursor mRNA and its cellular localization demonstrate that its expression is not confined to the brain regions and cells that exhibit the selective neuronal death characteristic of Alzheimer's disease. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. PMID:3322812

  16. Genetics Home Reference: Alzheimer disease

    MedlinePlus

    ... and Kathleen Bryan Alzheimer's Disease Research Center, Duke University Medical Center MalaCards: alzheimer disease MalaCards: alzheimer disease risk factor Merck Manual Consumer Version: Alzheimer Disease Quick Facts ...

  17. The levels of soluble versus insoluble brain Abeta distinguish Alzheimer's disease from normal and pathologic aging.

    PubMed

    Wang, J; Dickson, D W; Trojanowski, J Q; Lee, V M

    1999-08-01

    The abundance and solubility of Abeta peptides are critical determinants of amyloidosis in Alzheimer's disease (AD). Hence, we compared levels of total soluble, insoluble, and total Abeta1-40 and Abeta1-42 in AD brains with those in age-matched normal and pathologic aging brains using a sandwich enzyme-linked immunosorbent assay (ELISA). Since the measurement of Abeta1-40 and Abeta1-42 depends critically on the specificity of the monoclonal antibodies used in the sandwich ELISA, we first demonstrated that each assay is specific for Abeta1-40 or Abeta1-42 and the levels of these peptides are not affected by the amyloid precursor protein in the brain extracts. Thus, this sandwich ELISA enabled us to show that the average levels of total cortical soluble and insoluble Abeta1-40 and Abeta1-42 were highest in AD, lowest in normal aging, and intermediate in pathologic aging. Remarkably, the average levels of insoluble Abeta1-40 were increased 20-fold while the average levels of insoluble Abeta1-42 were increased only 2-fold in the AD brains compared to pathologic aging brains. Further, the soluble pools of Abeta1-40 and Abeta1-42 were the largest fractions of total Abeta in the normal brain (i.e., 50 and 23%, respectively), but they were the smallest in the AD brain (i.e., 2.7 and 0.7%, respectively) and intermediate (i.e., 8 and 0.8%, respectively) in pathologic aging brains. Thus, our data suggest that pathologic aging is a transition state between normal aging and AD. More importantly, our findings imply that a progressive shift of brain Abeta1-40 and Abeta1-42 from soluble to insoluble pools and a profound increase in the levels of insoluble Abeta1-40 plays mechanistic roles in the onset and/or progression of AD.

  18. Recent Developments in Understanding Brain Aging: Implications for Alzheimer's Disease and Vascular Cognitive Impairment.

    PubMed

    Deak, Ferenc; Freeman, Willard M; Ungvari, Zoltan; Csiszar, Anna; Sonntag, William E

    2016-01-01

    As the population of the Western world is aging, there is increasing awareness of age-related impairments in cognitive function and a rising interest in finding novel approaches to preserve cerebral health. A special collection of articles in The Journals of Gerontology: Biological Sciences and Medical Sciences brings together information of different aspects of brain aging, from latest developments in the field of neurodegenerative disorders to cerebral microvascular mechanisms of cognitive decline. It is emphasized that although the cellular changes that occur within aging neurons have been widely studied, more research is required as new signaling pathways are discovered that can potentially protect cells. New avenues for research targeting cellular senescence, epigenetics, and endocrine mechanisms of brain aging are also discussed. Based on the current literature it is clear that understanding brain aging and reducing risk for neurological disease with age requires searching for mechanisms and treatment options beyond the age-related changes in neuronal function. Thus, comprehensive approaches need to be developed that address the multiple, interrelated mechanisms of brain aging. Attention is brought to the importance of maintenance of cerebromicrovascular health, restoring neuroendocrine balance, and the pressing need for funding more innovative research into the interactions of neuronal, neuroendocrine, inflammatory and microvascular mechanisms of cognitive impairment, and Alzheimer's disease. PMID:26590911

  19. Acrolein is increased in Alzheimer's disease brain and is toxic to primary hippocampal cultures.

    PubMed

    Lovell, M A; Xie, C; Markesbery, W R

    2001-01-01

    Accumulating evidence implicates oxidative stress in the pathogenesis of several neurodegenerative diseases including Alzheimer's disease (AD). Increased lipid peroxidation, decreased levels of polyunsaturated fatty acids, and increased levels of 4-hydroxynonenal (HNE), F(2)-isoprostanes, and F(4)-neuroprostanes are present in the brain in AD. Acrolein, an alpha,beta-unsaturated aldehydic product of lipid peroxidation, is approximately 100 times more reactive than HNE and recently was demonstrated in neurofibrillary tangles in the brain in AD. In three brain regions of 10 AD patients compared with 8 age-matched control subjects, we found increased mean extractable acrolein, with the increases reaching statistical significance in the amygdala and hippocampus/parahippocampal gyrus. In hippocampal neuron cultures, acrolein was neurotoxic in a time- and concentration-dependent manner and more toxic than HNE at 5 microM concentrations of each. Acrolein exposure led to a significant concentration-dependent increase in intracellular calcium concentrations. Collectively, these data show that acrolein is increased in the brain in AD and demonstrate neurotoxicity mechanisms that might be important in the pathogenesis of neuron degeneration in AD.

  20. Recent Developments in Understanding Brain Aging: Implications for Alzheimer's Disease and Vascular Cognitive Impairment.

    PubMed

    Deak, Ferenc; Freeman, Willard M; Ungvari, Zoltan; Csiszar, Anna; Sonntag, William E

    2016-01-01

    As the population of the Western world is aging, there is increasing awareness of age-related impairments in cognitive function and a rising interest in finding novel approaches to preserve cerebral health. A special collection of articles in The Journals of Gerontology: Biological Sciences and Medical Sciences brings together information of different aspects of brain aging, from latest developments in the field of neurodegenerative disorders to cerebral microvascular mechanisms of cognitive decline. It is emphasized that although the cellular changes that occur within aging neurons have been widely studied, more research is required as new signaling pathways are discovered that can potentially protect cells. New avenues for research targeting cellular senescence, epigenetics, and endocrine mechanisms of brain aging are also discussed. Based on the current literature it is clear that understanding brain aging and reducing risk for neurological disease with age requires searching for mechanisms and treatment options beyond the age-related changes in neuronal function. Thus, comprehensive approaches need to be developed that address the multiple, interrelated mechanisms of brain aging. Attention is brought to the importance of maintenance of cerebromicrovascular health, restoring neuroendocrine balance, and the pressing need for funding more innovative research into the interactions of neuronal, neuroendocrine, inflammatory and microvascular mechanisms of cognitive impairment, and Alzheimer's disease.

  1. Docosahexaenoic acid homeostasis, brain aging and Alzheimer's disease: Can we reconcile the evidence?

    PubMed

    Cunnane, Stephen C; Chouinard-Watkins, Raphael; Castellano, Christian A; Barberger-Gateau, Pascale

    2013-01-01

    A crossroads has been reached on research into docosahexaenoic acid (DHA) and Alzheimer's disease (AD). On the one hand, several prospective observational studies now clearly indicate a protective effect of higher fish and DHA intake against risk of AD. On the other hand, once AD is clinically evident, supplementation trials demonstrate essentially no benefit of DHA in AD. Despite apparently low DHA intake in AD, brain DHA levels are frequently the same as in controls, suggesting that low DHA intake results in low plasma DHA but does not necessarily reduce brain DHA in humans. Animal models involving dietary omega-3 fatty acid deficiency to deplete brain DHA may therefore not be appropriate in AD research. Studies in the healthy elderly suggest that DHA homeostasis changes during aging. Tracer methodology now permits estimation of DHA half-life in the human brain and whole body. Apolipoprotein E alleles have an important impact not only on AD but also on DHA homeostasis in humans. We therefore encourage further development of innovative approaches to the study of DHA metabolism and its role in human brain function. A better understanding of DHA metabolism in humans will hopefully help explain how higher habitual DHA intake protects against the risk of deteriorating cognition during aging and may eventually give rise to a breakthrough in the treatment of AD. PMID:22575581

  2. Nitric oxide as an initiator of brain lesions during the development of Alzheimer disease.

    PubMed

    Aliev, Gjumrakch; Palacios, Hector H; Lipsitt, Amanda E; Fischbach, Kathryn; Lamb, Bruce T; Obrenovich, Mark E; Morales, Ludis; Gasimov, Eldar; Bragin, Valentin

    2009-10-01

    Nitric oxide (NO) is an important regulatory molecule for the host defense that plays a fundamental role in the cardiovascular, immune, and nervous systems. NO is synthesized through the conversion of L-arginine to L-citrulline by the enzyme NO synthase (NOS), which is found in three isoforms classified as neuronal (nNOS), inducible (iNOS), and endothelial (eNOS). Recent evidence supports the theory that this bioactive molecule has an influential role in the disruption of normal brain and vascular homeostasis, a condition known to elucidate chronic hypoperfusion which ultimately causes the development of brain lesions and the pathology that typify Alzheimer disease (AD). In addition, vascular NO activity appears to be a major contributor to this pathology before any overexpression of NOS isoforms is observed in the neuron, glia, and microglia of the brain tree, where the overexpression the NOS isoforms causes the formation of a large amount of NO. We hypothesize that since an imbalance between the NOS isoforms and endothelin-1 (ET-1), a human gene that encodes for blood vessel constriction, can cause antioxidant system insufficiency; by using pharmacological intervention with NO donors and/or NO suppressors, the brain lesions and the downstream progression of brain pathology and dementia in AD should be delayed or minimized.

  3. Preliminary study of Alzheimer's Disease diagnosis based on brain electrical signals using wireless EEG

    NASA Astrophysics Data System (ADS)

    Handayani, N.; Akbar, Y.; Khotimah, S. N.; Haryanto, F.; Arif, I.; Taruno, W. P.

    2016-03-01

    This research aims to study brain's electrical signals recorded using EEG as a basis for the diagnosis of patients with Alzheimer's Disease (AD). The subjects consisted of patients with AD, and normal subjects are used as the control. Brain signals are recorded for 3 minutes in a relaxed condition and with eyes closed. The data is processed using power spectral analysis, brain mapping and chaos test to observe the level of complexity of EEG's data. The results show a shift in the power spectral in the low frequency band (delta and theta) in AD patients. The increase of delta and theta occurs in lobus frontal area and lobus parietal respectively. However, there is a decrease of alpha activity in AD patients where in the case of normal subjects with relaxed condition, brain alpha wave dominates the posterior area. This is confirmed by the results of brain mapping. While the results of chaos analysis show that the average value of MMLE is lower in AD patients than in normal subjects. The level of chaos associated with neural complexity in AD patients with lower neural complexity is due to neuronal damage caused by the beta amyloid plaques and tau protein in neurons.

  4. Divergent brain functional network alterations in dementia with Lewy bodies and Alzheimer's disease

    PubMed Central

    Peraza, Luis R.; Taylor, John-Paul; Kaiser, Marcus

    2015-01-01

    The clinical phenotype of dementia with Lewy bodies (DLB) is different from Alzheimer's disease (AD), suggesting a divergence between these diseases in terms of brain network organization. To fully understand this, we studied functional networks from resting-state functional magnetic resonance imaging in cognitively matched DLB and AD patients. The DLB group demonstrated a generalized lower synchronization compared with the AD and healthy controls, and this was more severe for edges connecting distant brain regions. Global network measures were significantly different between DLB and AD. For instance, AD showed lower small-worldness than healthy controls, while DLB showed higher small-worldness (AD < controls < DLB), and this was also the case for global efficiency (DLB > controls > AD) and clustering coefficient (DLB < controls < AD). Differences were also found for nodal measures at brain regions associated with each disease. Finally, we found significant associations between network performance measures and global cognitive impairment and severity of cognitive fluctuations in DLB. These results show network divergences between DLB and AD which appear to reflect their neuropathological differences. PMID:26115566

  5. New insights into brain BDNF function in normal aging and Alzheimer disease.

    PubMed

    Tapia-Arancibia, Lucia; Aliaga, Esteban; Silhol, Michelle; Arancibia, Sandor

    2008-11-01

    The decline observed during aging involves multiple factors that influence several systems. It is the case for learning and memory processes which are severely reduced with aging. It is admitted that these cognitive effects result from impaired neuronal plasticity, which is altered in normal aging but mainly in Alzheimer disease. Neurotrophins and their receptors, notably BDNF, are expressed in brain areas exhibiting a high degree of plasticity (i.e. the hippocampus, cerebral cortex) and are considered as genuine molecular mediators of functional and morphological synaptic plasticity. Modification of BDNF and/or the expression of its receptors (TrkB.FL, TrkB.T1 and TrkB.T2) have been described during normal aging and Alzheimer disease. Interestingly, recent findings show that some physiologic or pathologic age-associated changes in the central nervous system could be offset by administration of exogenous BDNF and/or by stimulating its receptor expression. These molecules may thus represent a physiological reserve which could determine physiological or pathological aging. These data suggest that boosting the expression or activity of these endogenous protective systems may be a promising therapeutic alternative to enhance healthy aging.

  6. Demonstration of aluminum in amyloid fibers in the cores of senile plaques in the brains of patients with Alzheimer's disease.

    PubMed

    Yumoto, Sakae; Kakimi, Shigeo; Ohsaki, Akihiro; Ishikawa, Akira

    2009-11-01

    Aluminum (Al) exposure has been reported to be a risk factor for Alzheimer's disease (senile dementia of Alzheimer type), although the role of Al in the etiology of Alzheimer's disease remains controversial. We examined the presence of Al in the Alzheimer's brain using energy-dispersive X-ray spectroscopy combined with transmission electron microscopy (TEM-EDX). TEM-EDX analysis allows simultaneous imaging of subcellular structures with high spatial resolution and analysis of small quantities of elements contained in the same subcellular structures. We identified senile plaques by observation using TEM and detected Al in amyloid fibers in the cores of senile plaques located in the hippocampus and the temporal lobe by EDX. Phosphorus and calcium were also present in the amyloid fibers. No Al could be detected in the extracellular space in senile plaques or in the cytoplasm of nerve cells. In this study, we demonstrated colocalization of Al and beta-amyloid (Abeta) peptides in amyloid fibers in the cores of senile plaques. The results support the following possibilities in the brains of patients with Alzheimer's disease: Al could be involved in the aggregation of Abeta peptides to form toxic fibrils; Al might induce Abeta peptides into the beta-sheet structure; and Al might facilitate iron-mediated oxidative reactions, which cause severe damage to brain tissues.

  7. Regional and Gender Study of Neuronal Density in Brain during Aging and in Alzheimer's Disease

    PubMed Central

    Martínez-Pinilla, Eva; Ordóñez, Cristina; del Valle, Eva; Navarro, Ana; Tolivia, Jorge

    2016-01-01

    Background: Learning processes or language development are only some of the cognitive functions that differ qualitatively between men and women. Gender differences in the brain structure seem to be behind these variations. Indeed, this sexual dimorphism at neuroanatomical level is accompanied unequivocally by differences in the way that aging and neurodegenerative diseases affect men and women brains. Objective: The aim of this study is the analysis of neuronal density in four areas of the hippocampus, and entorhinal and frontal cortices to analyze the possible gender influence during normal aging and in Alzheimer's disease (AD). Methods: Human brain tissues of different age and from both sexes, without neurological pathology and with different Braak's stages of AD, were studied. Neuronal density was quantified using the optical dissector. Results: Our results showed the absence of a significant neuronal loss during aging in non-pathological brains in both sexes. However, we have demonstrated specific punctual significant variations in neuronal density related with the age and gender in some regions of these brains. In fact, we observed a higher neuronal density in CA3 and CA4 hippocampal areas of non-pathological brains of young men compared to women. During AD, we observed a negative correlation between Braak's stages and neuronal density in hippocampus, specifically in CA1 for women and CA3 for men, and in frontal cortex for both, men and women. Conclusion: Our data demonstrated a sexual dimorphism in the neuronal vulnerability to degeneration suggesting the need to consider the gender of the individuals in future studies, regarding neuronal loss in aging and AD, in order to avoid problems in interpreting data.

  8. Regional and Gender Study of Neuronal Density in Brain during Aging and in Alzheimer's Disease

    PubMed Central

    Martínez-Pinilla, Eva; Ordóñez, Cristina; del Valle, Eva; Navarro, Ana; Tolivia, Jorge

    2016-01-01

    Background: Learning processes or language development are only some of the cognitive functions that differ qualitatively between men and women. Gender differences in the brain structure seem to be behind these variations. Indeed, this sexual dimorphism at neuroanatomical level is accompanied unequivocally by differences in the way that aging and neurodegenerative diseases affect men and women brains. Objective: The aim of this study is the analysis of neuronal density in four areas of the hippocampus, and entorhinal and frontal cortices to analyze the possible gender influence during normal aging and in Alzheimer's disease (AD). Methods: Human brain tissues of different age and from both sexes, without neurological pathology and with different Braak's stages of AD, were studied. Neuronal density was quantified using the optical dissector. Results: Our results showed the absence of a significant neuronal loss during aging in non-pathological brains in both sexes. However, we have demonstrated specific punctual significant variations in neuronal density related with the age and gender in some regions of these brains. In fact, we observed a higher neuronal density in CA3 and CA4 hippocampal areas of non-pathological brains of young men compared to women. During AD, we observed a negative correlation between Braak's stages and neuronal density in hippocampus, specifically in CA1 for women and CA3 for men, and in frontal cortex for both, men and women. Conclusion: Our data demonstrated a sexual dimorphism in the neuronal vulnerability to degeneration suggesting the need to consider the gender of the individuals in future studies, regarding neuronal loss in aging and AD, in order to avoid problems in interpreting data. PMID:27679571

  9. Brain changes in older adults at very low risk for Alzheimer's disease.

    PubMed

    Fjell, Anders M; McEvoy, Linda; Holland, Dominic; Dale, Anders M; Walhovd, Kristine B

    2013-05-01

    Alzheimer's disease (AD) has a slow onset, so it is challenging to distinguish brain changes in healthy elderly persons from incipient AD. One-year brain changes with a distinct frontotemporal pattern have been shown in older adults. However, it is not clear to what extent these changes may have been affected by undetected, early AD. To address this, we estimated 1-year atrophy by magnetic resonance imaging (MRI) in 132 healthy elderly persons who had remained free of diagnosed mild cognitive impairment or AD for at least 3 years. We found significant volumetric reductions throughout the brain. The sample was further divided into low-risk groups based on clinical, biomarker, genetic, or cognitive criteria. Although sample sizes varied, significant reductions were observed in all groups, with rates and topographical distribution of atrophy comparable to that of the full sample. Volume reductions were especially pronounced in the default mode network, closely matching the previously described frontotemporal pattern of changes in healthy aging. Atrophy in the hippocampus predicted change in memory, with no additional default mode network contributions. In conclusion, reductions in regional brain volumes can be detected over the course of 1 year even in older adults who are unlikely to be in a presymptomatic stage of AD.

  10. Insulin Receptor Expression and Activity in the Brains of Nondiabetic Sporadic Alzheimer's Disease Cases

    PubMed Central

    Ho, Lap; Yemul, Shrishailam; Knable, Lindsay; Katsel, Pavel; Zhao, Rudy; Haroutunian, Vahram; Pasinetti, Giulio Maria

    2012-01-01

    We investigated the contents of the insulin receptor-beta subunit (IRβ) and [Tyr1162/1163]-phosphorylated IRβ as surrogate indices of total IR content and IR activation in postmortem hippocampal formation brain specimens from nondiabetic sporadic Alzheimer's disease (AD) cases. We found no significant changes in the brain contents of total IRβ or [Tyr1162/1163]-phosphorylated IRβ, suggesting normal IR content and activation in the brains of nondiabetic sporadic AD cases. Moreover, total IRβ and [Tyr1162/1163]-phosphorylated IRβ levels in the hippocampal formation are not correlated with the severity of amyloid or tau-neuropathology. Exploring the regulation of glycogen synthase kinase 3 (GSK3) α/β, key IR-signaling components, we observed significantly lower levels of total GSK3 α/β in brain specimens from nondiabetic AD cases, suggesting that impaired IR signaling mechanisms might contribute to the onset and/or progression of AD dementia. Outcomes from our study support the development of insulin-sensitizing therapeutic strategies to stimulate downstream IR signaling in nondiabetic AD cases. PMID:22666619

  11. The Nuclear Receptor PPARγ as a Therapeutic Target for Cerebrovascular and Brain Dysfunction in Alzheimer's Disease

    PubMed Central

    Nicolakakis, Nektaria; Hamel, Edith

    2010-01-01

    Peroxisome proliferator-activated receptors (PPARs) are ligand-activated nuclear transcription factors that regulate peripheral lipid and glucose metabolism. Three subtypes make up the PPAR family (α, γ, β/δ), and synthetic ligands for PPARα (fibrates) and PPARγ (Thiazolidinediones, TZDs) are currently prescribed for the respective management of dyslipidemia and type 2 diabetes. In contrast to the well characterized action of PPARs in the periphery, little was known about the presence or function of these receptors in the brain and cerebral vasculature until fairly recently. Indeed, research in the last decade has uncovered these receptors in most brain cell types, and has shown that their activation, particularly that of PPARγ, is implicated in normal brain and cerebrovascular physiology, and confers protection under pathological conditions. Notably, accumulating evidence has highlighted the therapeutic potential of PPARγ ligands in the treatment of brain disorders such as Alzheimer's disease (AD), leading to the testing of the TZDs pioglitazone and rosiglitazone in AD clinical trials. This review will focus on the benefits of PPARγ agonists for vascular, neuronal and glial networks, and assess the value of these compounds as future AD therapeutics in light of evidence from transgenic mouse models and recent clinical trials. PMID:20725514

  12. Physical Exercise and Brain Mitochondrial Fitness: The Possible Role Against Alzheimer's Disease.

    PubMed

    Bernardo, T C; Marques-Aleixo, I; Beleza, J; Oliveira, P J; Ascensão, A; Magalhães, J

    2016-09-01

    Exercise is one of the most effective strategies to maintain a healthy body and mind, with particular beneficial effects of exercise on promoting brain plasticity, increasing cognition and reducing the risk of cognitive decline and dementia in later life. Moreover, the beneficial effects resulting from increased physical activity occur at different levels of cellular organization, mitochondria being preferential target organelles. The relevance of this review article relies on the need to integrate the current knowledge of proposed mechanisms, focus mitochondria, to explain the protective effects of exercise that might underlie neuroplasticity and seeks to synthesize these data in the context of exploring exercise as a feasible intervention to delay cognitive impairment associated with neurodegenerative conditions, particularly Alzheimer disease. PMID:27328058

  13. 7 Warning Signs of Alzheimer's | Alzheimer's disease | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Alzheimer's Disease 7 Warning Signs of Alzheimer's Past Issues / Fall 2010 Table of Contents The ... Suncoast Gerontology Center, University of South Florida. How Alzheimer's Changes the Brain The only definite way to ...

  14. Cognitive aging and Alzheimer's disease

    PubMed Central

    Vandenberghe, R; Tournoy, J

    2005-01-01

    Cognitive aging and clinically probable Alzheimer's disease can be discriminated by means of clinical and neuropsychological testing, and structural and functional imaging techniques. Research at the level of cognitive brain systems and at the molecular level provides exciting new insights into the relation between aging and neurodegeneration. The advances at the clinical and at the basic research levels are necessary if we wish to meet the formidable challenge that the increasing prevalence of Alzheimer's disease poses to the medical community. PMID:15937198

  15. Voxel-based discriminant map classification on brain ventricles for Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Wang, Jingnan; de Haan, Gerard; Unay, Devrim; Soldea, Octavian; Ekin, Ahmet

    2009-02-01

    One major hallmark of the Alzheimer's disease (AD) is the loss of neurons in the brain. In many cases, medical experts use magnetic resonance imaging (MRI) to qualitatively measure the neuronal loss by the shrinkage or enlargement of the structures-of-interest. Brain ventricle is one of the popular choices. It is easily detectable in clinical MR images due to the high contrast of the cerebro-spinal fluid (CSF) with the rest of the parenchyma. Moreover, atrophy in any periventricular structure will directly lead to ventricle enlargement. For quantitative analysis, volume is the common choice. However, volume is a gross measure and it cannot capture the entire complexity of the anatomical shape. Since most existing shape descriptors are complex and difficult-to-reproduce, more straightforward and robust ways to extract ventricle shape features are preferred in the diagnosis. In this paper, a novel ventricle shape based classification method for Alzheimer's disease has been proposed. Training process is carried out to generate two probability maps for two training classes: healthy controls (HC) and AD patients. By subtracting the HC probability map from the AD probability map, we get a 3D ventricle discriminant map. Then a matching coefficient has been calculated between each training subject and the discriminant map. An adjustable cut-off point of the matching coefficients has been drawn for the two classes. Generally, the higher the cut-off point that has been drawn, the higher specificity can be achieved. However, it will result in relatively lower sensitivity and vice versa. The benchmarked results against volume based classification show that the area under the ROC curves for our proposed method is as high as 0.86 compared with only 0.71 for volume based classification method.

  16. [Immunotherapy for Alzheimer's disease].

    PubMed

    Falkentoft, Alexander Christian; Hasselbalch, Steen Gregers

    2016-01-18

    Passive anti-beta-amyloid (Aß) immunotherapy has been shown to clear brain Aß deposits. Results from phase III clinical trials in mild-to-moderate Alzheimer's disease (AD) patients with two monoclonal antibodies bapineuzumab and solanezumab and intravenous immunoglobulin have been disappointing. Subsequent analysis of pooled data from both phase III trials with solanezumab showed a reduction in cognitive decline in patients with mild AD. Solanezumab and new monoclonal antibodies are being tested in patients with prodromal and preclinical AD in search for a disease-modifying treatment. PMID:26815584

  17. Cellular model studies of brain-mediated phototherapy on Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Zhu, Ling; Liu, Timon Cheng-Yi; Hu, Bina; Li, Xiao-Yun; Wang, Yong-Qing

    2008-12-01

    Alzheimer's disease (AD) is now the most common neurodegenerative disease. Despite approval of several drugs for AD, the disease continues to rob millions of their memories and their lives. We have studied the cellular models of brain-mediated phototherapy on AD, and the studies will be reviewed in this paper. Genetic studies have shown that dysfunction of amyloid β-protein (Aβ) or tau is sufficient to cause AD. Aβ or Aβ induced redox stress induced neuron apoptosis might be as a cellular model of AD. We found red light at 640+/-15 nm from light emitting diode array (RLED640) might inhibit Aβ 25-35 induced PC12 cell apoptosis, which is mediated by cyclic adenosine monophosphate, and it might inhibit hydrogen peroxide (H2O2) induced differentiated PC12 cell (dPC12) apoptosis, which is mediated by tyrosine hydroxylase. There is rhythm dysfunction in AD. We found low intensity 810 nm laser irradiation might rehabilitate TNF-alpha induced inhibition of clock gen expression of NIH 3T3 fibroblasts. Our studies provide a foundation for photobiomodulation on brain to rehabilitate AD.

  18. Intranasal nanoparticles of basic fibroblast growth factor for brain delivery to treat Alzheimer's disease.

    PubMed

    Zhang, Chi; Chen, Jie; Feng, Chengcheng; Shao, Xiayan; Liu, Qingfeng; Zhang, Qizhi; Pang, Zhiqing; Jiang, Xinguo

    2014-01-30

    Disabilities caused by neurodegeneration have become one of the main causes of mortality in elderly population, with drug distribution to the brain remaining one of the most difficult challenges in the treatment of the central nervous system (CNS) diseases due to the existence of blood-brain barrier. Lectins modified polyethylene glycol-polylactide-polyglycolide (PEG-PLGA) nanoparticles could enhance the drug delivery to the brain following intranasal administration. In this study, basic fibroblast growth factor (bFGF) was entrapped in nanoparticles conjugated with Solanum tuberosum lectin (STL), which selectively binds to N-acetylglucosamine on the nasal epithelial membrane for its brain delivery. The resulting nanoparticles had uniform particle size and negative zeta potential. The brain distribution of the formulations following intranasal administration was assessed using radioisotopic tracing method. The areas under the concentration-time curve of (125)I-bFGF in the olfactory bulb, cerebrum, and cerebellum of rats following nasal application of STL modified nanoparticles (STL-bFGF-NP) were 1.79-5.17 folds of that of rats with intravenous administration, and 0.61-2.21 and 0.19-1.07 folds higher compared with intranasal solution and unmodified nanoparticles, respectively. Neuroprotective effect was evaluated using Mirror water maze task in rats with intracerebroventricular injection of β-amyloid25-35 and ibotenic acid. The spatial learning and memory of Alzheimer's disease (AD) rats in STL-bFGF-NP group were significantly improved compared with AD model group, and were also better than other preparations. The results were consistent with the value of choline acetyltransferase activity of rat hippocampus as well as the histological observations of rat hippocampal region. The histopathology assays also confirmed the in vivo safety of STL-bFGF-NP. These results clearly indicated that STL-NP was a promising drug delivery system for peptide and protein drugs such as

  19. Loss of neprilysin alters protein expression in the brain of Alzheimer's disease model mice.

    PubMed

    Nilsson, Per; Loganathan, Krishnapriya; Sekiguchi, Misaki; Winblad, Bengt; Iwata, Nobuhisa; Saido, Takaomi C; Tjernberg, Lars O

    2015-10-01

    Alzheimer's disease (AD) is a neurodegenerative disease displaying extracellular plaques formed by the neurotoxic amyloid β-peptide (Aβ), and intracellular neurofibrillary tangles consisting of protein tau. However, how these pathologies relate to the massive neuronal death that occurs in AD brains remain elusive. Neprilysin is the major Aβ-degrading enzyme and a lack thereof increases Aβ levels in the brain twofold. To identify altered protein expression levels induced by increased Aβ levels, we performed a proteomic analysis of the brain of the AD mouse model APPsw and compared it to that of APPsw mice lacking neprilysin. To this end we established an LC-MS/MS method to analyze brain homogenate, using an (18) O-labeled internal standard to accurately quantify the protein levels. To distinguish between alterations in protein levels caused by increased Aβ levels and those induced by neprilysin deficiency independently of Aβ, the brain proteome of neprilysin deficient APPsw mice was also compared to that of neprilysin deficient mice. By this approach we identified approximately 600 proteins and the levels of 300 of these were quantified. Pathway analysis showed that many of the proteins with altered expression were involved in neurological disorders, and that tau, presenilin and APP were key regulators in the identified networks. The data have been deposited to the ProteomeXchange Consortium with identifiers PXD000968 and PXD001786 (http://proteomecentral.proteomexchange.org/dataset/PXD000968 and (http://proteomecentral.proteomexchange.org/dataset/PXD001786). Interestingly, the levels of several proteins, including some not previously reported to be linked to AD, were associated with increased Aβ levels.

  20. Intranasal nanoparticles of basic fibroblast growth factor for brain delivery to treat Alzheimer's disease.

    PubMed

    Zhang, Chi; Chen, Jie; Feng, Chengcheng; Shao, Xiayan; Liu, Qingfeng; Zhang, Qizhi; Pang, Zhiqing; Jiang, Xinguo

    2014-01-30

    Disabilities caused by neurodegeneration have become one of the main causes of mortality in elderly population, with drug distribution to the brain remaining one of the most difficult challenges in the treatment of the central nervous system (CNS) diseases due to the existence of blood-brain barrier. Lectins modified polyethylene glycol-polylactide-polyglycolide (PEG-PLGA) nanoparticles could enhance the drug delivery to the brain following intranasal administration. In this study, basic fibroblast growth factor (bFGF) was entrapped in nanoparticles conjugated with Solanum tuberosum lectin (STL), which selectively binds to N-acetylglucosamine on the nasal epithelial membrane for its brain delivery. The resulting nanoparticles had uniform particle size and negative zeta potential. The brain distribution of the formulations following intranasal administration was assessed using radioisotopic tracing method. The areas under the concentration-time curve of (125)I-bFGF in the olfactory bulb, cerebrum, and cerebellum of rats following nasal application of STL modified nanoparticles (STL-bFGF-NP) were 1.79-5.17 folds of that of rats with intravenous administration, and 0.61-2.21 and 0.19-1.07 folds higher compared with intranasal solution and unmodified nanoparticles, respectively. Neuroprotective effect was evaluated using Mirror water maze task in rats with intracerebroventricular injection of β-amyloid25-35 and ibotenic acid. The spatial learning and memory of Alzheimer's disease (AD) rats in STL-bFGF-NP group were significantly improved compared with AD model group, and were also better than other preparations. The results were consistent with the value of choline acetyltransferase activity of rat hippocampus as well as the histological observations of rat hippocampal region. The histopathology assays also confirmed the in vivo safety of STL-bFGF-NP. These results clearly indicated that STL-NP was a promising drug delivery system for peptide and protein drugs such as

  1. The Role of Brain Cholesterol and its Oxidized Products in Alzheimer's Disease.

    PubMed

    Giudetti, Anna Maria; Romano, Adele; Lavecchia, Angelo Michele; Gaetani, Silvana

    2016-01-01

    The human brain is the most cholesterol-rich organ harboring 25% of the total cholesterol pool of the whole body. Cholesterol present in the central nervous system (CNS) comes, almost entirely, from the endogenous synthesis, being circulating cholesterol unable to cross the blood-brain barrier (BBB). Astrocytes seem to be more active than neurons in this process. Neurons mostly depend on cholesterol delivery from nearby cells for axonal regeneration, neurite extension and synaptogenesis. Within the brain, cholesterol is transported by HDL-like lipoproteins associated to apoE which represents the main apolipoprotein in the CNS. Although CNS cholesterol content is largely independent of dietary intake or hepatic synthesis, a relationship between plasma cholesterol level and neurodegenerative disorders, such as Alzheimer's disease (AD), has often been reported. To this regard, alterations of cholesterol metabolism were suggested to be implicated in the etiology of AD and amyloid production in the brain. Therefore a special attention was dedicated to the study of the main factors controlling cholesterol metabolism in the brain. Brain cholesterol levels are tightly controlled: its excessive amount can be reduced through the conversion into the oxidized form of 24-S-hydroxycholesetrol (24-OH-C), which can reach the blood stream. In fact, the BBB is permeable to 24-OH-C as well as to 27-OH-C, another oxidized form of cholesterol mainly synthesized by non- neural cells. In this review, we summarize the main mechanisms regulating cholesterol homeostasis and review the recent advances on the role played by cholesterol and cholesterol oxidized products in AD. Moreover, we delineate possible pharmacological strategies to control AD progression by affecting cholesterol homeostasis.

  2. The hunt for brain Aβ oligomers by peripherally circulating multi-functional nanoparticles: Potential therapeutic approach for Alzheimer disease.

    PubMed

    Mancini, Simona; Minniti, Stefania; Gregori, Maria; Sancini, Giulio; Cagnotto, Alfredo; Couraud, Pierre-Olivier; Ordóñez-Gutiérrez, Lara; Wandosell, Francisco; Salmona, Mario; Re, Francesca

    2016-01-01

    We previously showed the ability of liposomes bi-functionalized with phosphatidic acid and an ApoE-derived peptide (mApoE-PA-LIP) to reduce brain Aβ in transgenic Alzheimer mice. Herein we investigated the efficacy of mApoE-PA-LIP to withdraw Aβ peptide in different aggregation forms from the brain, using a transwell cellular model of the blood-brain barrier and APP/PS1 mice. The spontaneous efflux of Aβ oligomers (Aβo), but not of Aβ fibrils, from the 'brain' side of the transwell was strongly enhanced (5-fold) in presence of mApoE-PA-LIP in the 'blood' compartment. This effect is due to a withdrawal of Aβo exerted by peripheral mApoE-PA-LIP by sink effect, because, when present in the brain side, they did not act as Aβo carrier and limit the oligomer efflux. In vivo peripheral administration of mApoE-PA-LIP significantly increased the plasma Aβ level, suggesting that Aβ-binding particles exploiting the sink effect can be used as a therapeutic strategy for Alzheimer disease. From the Clinical Editor: Alzheimer disease (AD) at present is an incurable disease, which is thought to be caused by an accumulation of amyloid-β (Aβ) peptides in the brain. Many strategies in combating this disease have been focused on either the prevention or dissolving these peptides. In this article, the authors showed the ability of liposomes bi-functionalized with phosphatidic acid and with an ApoE- derived peptide to withdraw amyloid peptides from the brain. The data would help the future design of more novel treatment for Alzheimer disease. PMID:26410276

  3. The hunt for brain Aβ oligomers by peripherally circulating multi-functional nanoparticles: Potential therapeutic approach for Alzheimer disease.

    PubMed

    Mancini, Simona; Minniti, Stefania; Gregori, Maria; Sancini, Giulio; Cagnotto, Alfredo; Couraud, Pierre-Olivier; Ordóñez-Gutiérrez, Lara; Wandosell, Francisco; Salmona, Mario; Re, Francesca

    2016-01-01

    We previously showed the ability of liposomes bi-functionalized with phosphatidic acid and an ApoE-derived peptide (mApoE-PA-LIP) to reduce brain Aβ in transgenic Alzheimer mice. Herein we investigated the efficacy of mApoE-PA-LIP to withdraw Aβ peptide in different aggregation forms from the brain, using a transwell cellular model of the blood-brain barrier and APP/PS1 mice. The spontaneous efflux of Aβ oligomers (Aβo), but not of Aβ fibrils, from the 'brain' side of the transwell was strongly enhanced (5-fold) in presence of mApoE-PA-LIP in the 'blood' compartment. This effect is due to a withdrawal of Aβo exerted by peripheral mApoE-PA-LIP by sink effect, because, when present in the brain side, they did not act as Aβo carrier and limit the oligomer efflux. In vivo peripheral administration of mApoE-PA-LIP significantly increased the plasma Aβ level, suggesting that Aβ-binding particles exploiting the sink effect can be used as a therapeutic strategy for Alzheimer disease. From the Clinical Editor: Alzheimer disease (AD) at present is an incurable disease, which is thought to be caused by an accumulation of amyloid-β (Aβ) peptides in the brain. Many strategies in combating this disease have been focused on either the prevention or dissolving these peptides. In this article, the authors showed the ability of liposomes bi-functionalized with phosphatidic acid and with an ApoE- derived peptide to withdraw amyloid peptides from the brain. The data would help the future design of more novel treatment for Alzheimer disease.

  4. Alzheimer Disease Alters the Relationship of Cardiorespiratory Fitness With Brain Activity During the Stroop Task

    PubMed Central

    Gayed, Matthew R.; Honea, Robyn A.; Savage, Cary R.; Hobbs, Derek; Burns, Jeffrey M.

    2013-01-01

    Background Despite mounting evidence that physical activity has positive benefits for brain and cognitive health, there has been little characterization of the relationship between cardiorespiratory (CR) fitness and cognition-associated brain activity as measured by functional magnetic resonance imaging (fMRI). The lack of evidence is particularly glaring for diseases such as Alzheimer disease (AD) that degrade cognitive and functional performance. Objective The aim of this study was to describe the relationship between regional brain activity during cognitive tasks and CR fitness level in people with and without AD. Design A case-control, single-observation study design was used. Methods Thirty-four individuals (18 without dementia and 16 in the earliest stages of AD) completed maximal exercise testing and performed a Stroop task during fMRI. Results Cardiorespiratory fitness was inversely associated with anterior cingulate activity in the participants without dementia (r=−.48, P=.05) and unassociated with activation in those with AD (P>.7). Weak associations of CR fitness and middle frontal cortex were noted. Limitations The wide age range and the use of a single task in fMRI rather than multiple tasks challenging different cognitive capacities were limitations of the study. Conclusions The results offer further support of the relationship between CR fitness and regional brain activity. However, this relationship may be attenuated by disease. Future work in this area may provide clinicians and researchers with interpretable and dependable regional fMRI biomarker signatures responsive to exercise intervention. It also may shed light on mechanisms by which exercise can support cognitive function. PMID:23559521

  5. Alzheimer's Disease

    MedlinePlus

    ... the parts of the brain that control thought, memory and language. People with AD may have trouble ... related problem, mild cognitive impairment (MCI), causes more memory problems than normal for people of the same ...

  6. A Spherical Brain Mapping of MR Images for the Detection of Alzheimer's Disease.

    PubMed

    Martinez-Murcia, F J; Górriz, J M; Ramírez, J; Ortiz, A; For The Alzheimer's Disease Neuroimaging Initiative

    2016-01-01

    Magnetic Resonance Imaging (MRI) is of fundamental importance in neuroscience, providing good contrast and resolution, as well as not being considered invasive. Despite the development of newer techniques involving radiopharmaceuticals, it is still a recommended tool in Alzheimer's Disease (AD) neurological practice to assess neurodegeneration, and recent research suggests that it could reveal changes in the brain even before the symptomatology appears. In this paper we propose a method that performs a Spherical Brain Mapping, using different measures to project the three-dimensional MR brain images onto two-dimensional maps revealing statistical characteristics of the tissue. The resulting maps could be assessed visually, but also perform a significant feature reduction that will allow further supervised or unsupervised processing, reducing the computational load while maintaining a large amount of the original information. We have tested our methodology against a MRI database comprising 180 AD affected patients and 180 normal controls, where some of the mappings have revealed as an optimum strategy for the automatic processing and characterization of AD patterns, achieving up to a 90.9% of accuracy, as well as significantly reducing the computational load. Additionally, our maps allow the visual analysis and interpretation of the images, which can be of great help in the diagnosis of this and other types of dementia. PMID:26971941

  7. Preserved pontine glucose metabolism in Alzheimer disease: A reference region for functional brain image (PET) analysis

    SciTech Connect

    Minoshima, Satoshi; Frey, K.A.; Foster, N.L.; Kuhl, D.W.

    1995-07-01

    Our goal was to examine regional preservation of energy metabolism in Alzheimer disease (AD) and to evaluate effects of PET data normalization to reference regions. Regional metabolic rates in the pons, thalamus, putamen, sensorimotor cortex, visual cortex, and cerebellum (reference regions) were determined stereotaxically and examined in 37 patients with probable AD and 22 normal controls based on quantitative {sup 18}FDG-PET measurements. Following normalization of metabolic rates of the parietotemporal association cortex and whole brain to each reference region, distinctions of the two groups were assessed. The pons showed the best preservation of glucose metabolism in AD. Other reference regions showed relatively preserved metabolism compared with the parietotemporal association cortex and whole brain, but had significant metabolic reduction. Data normalization to the pons not only enhanced statistical significance of metabolic reduction in the parietotemporal association cortex, but also preserved the presence of global cerebral metabolic reduction indicated in analysis of the quantitative data. Energy metabolism in the pons in probable AD is well preserved. The pons is a reliable reference for data normalization and will enhance diagnostic accuracy and efficiency of quantitative and nonquantitative functional brain imaging. 39 refs., 2 figs., 3 tabs.

  8. Quinoline-n-butylcyanoacrylate-based nanoparticles for brain targeting for the diagnosis of Alzheimer's disease.

    PubMed

    Kulkarni, Padmakar V; Roney, Celeste A; Antich, Peter P; Bonte, Frederick J; Raghu, Anjanapura V; Aminabhavi, Tejraj M

    2010-01-01

    A survey of research activity on nanoparticles (NPs) based on polymeric devices that could cross the blood-brain barrier (BBB) is given along with the presentation of our own data on the development of NPs of n-butyl-2-cyanoacrylate (BCA) for brain delivery to aid the early diagnosis of Alzheimer's disease (AD), a neurodegenerative disorder of the elderly people, the most prevalent form of dementia. Typical data are presented on in vivo detection of amyloid peptides (A beta) (amyloid plaques) that are used as targets for developing the biological markers for the diagnosis of AD. In order to develop efficient in vivo probes, polymeric n-butyl-2-cyanoacrylate (PBCA) NPs have been prepared and encapsulated with the radio-labeled amyloid affinity drug (125)I-clioquinol (CQ, 5-chloro-7-iodo-8-hydroxyquinoline) to improve the transport to brain and amyloid plaque retention of (125)I-CQ using the NPs of PBCA. The (125)I-CQ discriminately binds to the AD post-mortem brain tissue homogenates versus control. (125)I-CQ-PBCA NPs labeled the A beta plaques from the AD human post-mortem frontal cortical sections on paraffin-fixed slides. Storage phosphor imaging verified preferential uptake by AD brain sections compared to cortical control sections. The (125)I-CQ-PBCA NPs crossed the BBB in wild type mouse, giving an increased brain uptake measured in terms of % ID/g i.e., injected dose compared to (125)I-CQ. Brain retention of (125)I-CQ-PBCA NPs was significantly increased in the AD transgenic mice (APP/PS1) and in mice injected with aggregated A beta 42 peptide versus age-matched wild type controls. The results of this study are verified by in vivo storage phosphor imaging and validated by histopathological staining of plaques and select metal ions, viz. Fe(2+) and Cu(2+). The (125)I-CQ-PBCA NPs had more efficient brain entry and rapid clearance in normal mice and enhanced the retention in AD mouse brain demonstrating the ideal in vivo imaging characteristics. The (125)I

  9. Brain Insulin Resistance and Deficiency as Therapeutic Targets in Alzheimer's Disease

    PubMed Central

    de la Monte, Suzanne M

    2012-01-01

    Alzheimer's disease [AD] is the most common cause of dementia in North America. Despite 30+ years of intense investigation, the field lacks consensus regarding the etiology and pathogenesis of sporadic AD, and therefore we still do not know the best strategies for treating and preventing this debilitating and costly disease. However, growing evidence supports the concept that AD is fundamentally a metabolic disease with substantial and progressive derangements in brain glucose utilization and responsiveness to insulin and insulin-like growth factor [IGF] stimulation. Moreover, AD is now recognized to be heterogeneous in nature, and not solely the end-product of aberrantly processed, misfolded, and aggregated oligomeric amyloid-beta peptides and hyperphosphorylated tau. Other factors, including impairments in energy metabolism, increased oxidative stress, inflammation, insulin and IGF resistance, and insulin/IGF deficiency in the brain should be incorporated into all equations used to develop diagnostic and therapeutic approaches to AD. Herein, the contributions of impaired insulin and IGF signaling to AD-associated neuronal loss, synaptic disconnection, tau hyperphosphorylation, amyloid-beta accumulation, and impaired energy metabolism are reviewed. In addition, we discuss current therapeutic strategies and suggest additional approaches based on the hypothesis that AD is principally a metabolic disease similar to diabetes mellitus. Ultimately, our ability to effectively detect, monitor, treat, and prevent AD will require more efficient, accurate and integrative diagnostic tools that utilize clinical, neuroimaging, biochemical, and molecular biomarker data. Finally, it is imperative that future therapeutic strategies for AD abandon the concept of uni-modal therapy in favor of multi-modal treatments that target distinct impairments at different levels within the brain insulin/IGF signaling cascades. PMID:22329651

  10. The role of calsyntenin-3 in dystrophic neurite formation in Alzheimer's disease brain.

    PubMed

    Uchida, Yoko; Gomi, Fujiya

    2016-03-01

    β-Amyloid (Aβ) oligomers may play an important role in the early pathogenesis of Alzheimer's disease: cognitive impairment caused by synaptic dysfunction. Dystrophic neurites surrounding Aβ plaques, another pathological feature of Alzheimer's disease, are plaque-associated neuritic alterations preceding the appearance of synaptic loss. In the present review, we focus on the mechanism of dystrophic neurite formation by Aß oligomers, and discuss the neurotoxic role of Aβ-induced calsyntenin-3 in mediating dystrophic neurite formation. PMID:27018282

  11. Modular reorganization of brain resting state networks and its independent validation in Alzheimer's disease patients.

    PubMed

    Chen, Guangyu; Zhang, Hong-Ying; Xie, Chunming; Chen, Gang; Zhang, Zhi-Jun; Teng, Gao-Jun; Li, Shi-Jiang

    2013-01-01

    Previous studies have demonstrated disruption in structural and functional connectivity occurring in the Alzheimer's Disease (AD). However, it is not known how these disruptions alter brain network reorganization. With the modular analysis method of graph theory, and datasets acquired by the resting-state functional connectivity MRI (R-fMRI) method, we investigated and compared the brain organization patterns between the AD group and the cognitively normal control (CN) group. Our main finding is that the largest homotopic module (defined as the insula module) in the CN group was broken down to the pieces in the AD group. Specifically, it was discovered that the eight pairs of the bilateral regions (the opercular part of inferior frontal gyrus, area triangularis, insula, putamen, globus pallidus, transverse temporal gyri, superior temporal gyrus, and superior temporal pole) of the insula module had lost symmetric functional connection properties, and the corresponding gray matter concentration (GMC) was significant lower in AD group. We further quantified the functional connectivity changes with an index (index A) and structural changes with the GMC index in the insula module to demonstrate their great potential as AD biomarkers. We further validated these results with six additional independent datasets (271 subjects in six groups). Our results demonstrated specific underlying structural and functional reorganization from young to old, and for diseased subjects. Further, it is suggested that by combining the structural GMC analysis and functional modular analysis in the insula module, a new biomarker can be developed at the single-subject level.

  12. Altered expression of ZnT10 in Alzheimer's disease brain.

    PubMed

    Bosomworth, Helen J; Adlard, Paul A; Ford, Dianne; Valentine, Ruth A

    2013-01-01

    There is an increasing body of evidence suggesting that metal homeostasis is dysregulated in the pathology of Alzheimer's disease (AD). Although expression levels of several transporters belonging the SLC30 family, which comprises predominantly zinc transporters, have been studied in the AD brain, SLC30A10 (ZnT10) has not been studied in this context. To determine if dysregulated expression of ZnT10, which may transport both Zn and Mn, could be a factor that contributes to AD, we investigated if there were differences in ZnT10 mRNA levels in specimens of frontal cortex from AD patients and controls and also if brain tissue from the APP/PS1 transgenic (Tg) mouse model showed abnormal levels of ZnT10 mRNA expression. Our results show that ZnT10 is significantly (P<0.01) decreased in the frontal cortex in AD. Furthermore, we observed a significant decrease in ZnT10 mRNA levels in the APP/PS1-Tg mice compared with wild-type controls (P<0.01). Our results suggest that this dysregulation in ZnT10 could further contribute to disease progression.

  13. Histamine Induces Alzheimer's Disease-Like Blood Brain Barrier Breach and Local Cellular Responses in Mouse Brain Organotypic Cultures.

    PubMed

    Sedeyn, Jonathan C; Wu, Hao; Hobbs, Reilly D; Levin, Eli C; Nagele, Robert G; Venkataraman, Venkat

    2015-01-01

    Among the top ten causes of death in the United States, Alzheimer's disease (AD) is the only one that cannot be cured, prevented, or even slowed down at present. Significant efforts have been exerted in generating model systems to delineate the mechanism as well as establishing platforms for drug screening. In this study, a promising candidate model utilizing primary mouse brain organotypic (MBO) cultures is reported. For the first time, we have demonstrated that the MBO cultures exhibit increased blood brain barrier (BBB) permeability as shown by IgG leakage into the brain parenchyma, astrocyte activation as evidenced by increased expression of glial fibrillary acidic protein (GFAP), and neuronal damage-response as suggested by increased vimentin-positive neurons occur upon histamine treatment. Identical responses-a breakdown of the BBB, astrocyte activation, and neuronal expression of vimentin-were then demonstrated in brains from AD patients compared to age-matched controls, consistent with other reports. Thus, the histamine-treated MBO culture system may provide a valuable tool in combating AD.

  14. Toward a brain-computer interface for Alzheimer's disease patients by combining classical conditioning and brain state classification.

    PubMed

    Liberati, Giulia; Dalboni da Rocha, Josué Luiz; van der Heiden, Linda; Raffone, Antonino; Birbaumer, Niels; Olivetti Belardinelli, Marta; Sitaram, Ranganatha

    2012-01-01

    Brain-computer interfaces (BCIs) provide alternative methods for communicating and acting on the world, since messages or commands are conveyed from the brain to an external device without using the normal output pathways of peripheral nerves and muscles. Alzheimer's disease (AD) patients in the most advanced stages, who have lost the ability to communicate verbally, could benefit from a BCI that may allow them to convey basic thoughts (e.g., "yes" and "no") and emotions. There is currently no report of such research, mostly because the cognitive deficits in AD patients pose serious limitations to the use of traditional BCIs, which are normally based on instrumental learning and require users to self-regulate their brain activation. Recent studies suggest that not only self-regulated brain signals, but also involuntary signals, for instance related to emotional states, may provide useful information about the user, opening up the path for so-called "affective BCIs". These interfaces do not necessarily require users to actively perform a cognitive task, and may therefore be used with patients who are cognitively challenged. In the present hypothesis paper, we propose a paradigm shift from instrumental learning to classical conditioning, with the aim of discriminating "yes" and "no" thoughts after associating them to positive and negative emotional stimuli respectively. This would represent a first step in the development of a BCI that could be used by AD patients, lending a new direction not only for communication, but also for rehabilitation and diagnosis.

  15. Histamine Induces Alzheimer's Disease-Like Blood Brain Barrier Breach and Local Cellular Responses in Mouse Brain Organotypic Cultures.

    PubMed

    Sedeyn, Jonathan C; Wu, Hao; Hobbs, Reilly D; Levin, Eli C; Nagele, Robert G; Venkataraman, Venkat

    2015-01-01

    Among the top ten causes of death in the United States, Alzheimer's disease (AD) is the only one that cannot be cured, prevented, or even slowed down at present. Significant efforts have been exerted in generating model systems to delineate the mechanism as well as establishing platforms for drug screening. In this study, a promising candidate model utilizing primary mouse brain organotypic (MBO) cultures is reported. For the first time, we have demonstrated that the MBO cultures exhibit increased blood brain barrier (BBB) permeability as shown by IgG leakage into the brain parenchyma, astrocyte activation as evidenced by increased expression of glial fibrillary acidic protein (GFAP), and neuronal damage-response as suggested by increased vimentin-positive neurons occur upon histamine treatment. Identical responses-a breakdown of the BBB, astrocyte activation, and neuronal expression of vimentin-were then demonstrated in brains from AD patients compared to age-matched controls, consistent with other reports. Thus, the histamine-treated MBO culture system may provide a valuable tool in combating AD. PMID:26697497

  16. Histamine Induces Alzheimer's Disease-Like Blood Brain Barrier Breach and Local Cellular Responses in Mouse Brain Organotypic Cultures

    PubMed Central

    Sedeyn, Jonathan C.; Wu, Hao; Hobbs, Reilly D.; Levin, Eli C.; Nagele, Robert G.; Venkataraman, Venkat

    2015-01-01

    Among the top ten causes of death in the United States, Alzheimer's disease (AD) is the only one that cannot be cured, prevented, or even slowed down at present. Significant efforts have been exerted in generating model systems to delineate the mechanism as well as establishing platforms for drug screening. In this study, a promising candidate model utilizing primary mouse brain organotypic (MBO) cultures is reported. For the first time, we have demonstrated that the MBO cultures exhibit increased blood brain barrier (BBB) permeability as shown by IgG leakage into the brain parenchyma, astrocyte activation as evidenced by increased expression of glial fibrillary acidic protein (GFAP), and neuronal damage-response as suggested by increased vimentin-positive neurons occur upon histamine treatment. Identical responses—a breakdown of the BBB, astrocyte activation, and neuronal expression of vimentin—were then demonstrated in brains from AD patients compared to age-matched controls, consistent with other reports. Thus, the histamine-treated MBO culture system may provide a valuable tool in combating AD. PMID:26697497

  17. Role of by-products of lipid oxidation in Alzheimer's disease brain: a focus on acrolein.

    PubMed

    Singh, Manjeet; Dang, Thanh Nam; Arseneault, Madeleine; Ramassamy, Charles

    2010-01-01

    Abundant data consistently support the idea that oxidative stress occurs and is a constant feature of Alzheimer's disease (AD). Some recent evidence indicated that phenomenon is an early event and might be implicated in the pathogenesis of this disease. Lipid peroxidation leads to the formation of a number of aldehydes by-products, including malondialdehyde (MDA), 4-hydroxy-2-nonenal (HNE), and acrolein. The most abundant aldehydes are HNE and MDA while acrolein is the most reactive. Increased levels of specific HNE-histidine and glutathione-HNE Michael adducts in AD brain has been reported. Proteomic analysis demonstrated a large number of protein-bound HNE in AD brain. F2-isoprostanes (F2-IsoPs) levels and neuroprostanes were also significantly increased in mild cognitive impairment (MCI) patients and in late-stage AD. In brain from patients with AD, acrolein has been found to be elevated in hippocampus and temporal cortex where oxidative stress is high. Due to its high reactivity, acrolein is not only a marker of lipid peroxidation but also an initiator of oxidative stress by adducting cellular nucleophilic groups found on proteins, lipids, and nucleic acids. Interestingly, data indicates that lipid peroxidation occurs in the brain of MCI and also in preclinical AD patients suggesting that oxidative damage may play an early role in the pathogenesis of AD. In this review, we will summarize some mechanisms implicated in the toxicity of by-products of lipid peroxidation such as IsoPs, HNE, and acrolein and their implication in AD.

  18. Event-related potential markers of brain changes in preclinical familial Alzheimer disease

    PubMed Central

    Ally, B.A.; Celone, K.; McKeever, J.; Ruiz-Rizzo, A.L.; Lopera, F.; Stern, C.E.; Budson, A.E.

    2011-01-01

    Objectives: Event-related potentials (ERPs) can reflect differences in brain electrophysiology underlying cognitive functions in brain disorders such as dementia and mild cognitive impairment. To identify individuals at risk for Alzheimer disease (AD) we used high-density ERPs to examine brain physiology in young presymptomatic individuals (average age 34.2 years) who carry the E280A mutation in the presenilin-1 (PSEN1) gene and will go on to develop AD around the age of 45. Methods: Twenty-one subjects from a Colombian population with familial AD participated: 10 presymptomatic subjects positive for the PSEN1 mutation (carriers) and 11 siblings without the mutation (controls). Subjects performed a visual recognition memory test while 128-channel ERPs were recorded. Results: Despite identical behavioral performance, PSEN1 mutation carriers showed less positivity in frontal regions and more positivity in occipital regions, compared to controls. These differences were more pronounced during the 200–300 msec period. Discriminant analysis at this time interval showed promising sensitivity (72.7%) and specificity (81.8%) of the ERP measures to predict the presence of AD pathology. Conclusions: Presymptomatic PSEN1 mutation carriers show changes in brain physiology that can be detected by high-density ERPs. The relative differences observed showing greater frontal positivity in controls and greater occipital positivity in carriers indicates that control subjects may use frontally mediated processes to distinguish between studied and unstudied visual items, whereas carriers appear to rely more upon perceptual details of the items to distinguish between them. These findings also demonstrate the potential usefulness of ERP brain correlates as preclinical markers of AD. PMID:21775732

  19. A Neuroprotective Brain-penetrating Endopeptidase Fusion Protein Ameliorates Alzheimer Disease Pathology and Restores Neurogenesis*

    PubMed Central

    Spencer, Brian; Verma, Inder; Desplats, Paula; Morvinski, Dinorah; Rockenstein, Ed; Adame, Anthony; Masliah, Eliezer

    2014-01-01

    Alzheimer disease (AD) is characterized by widespread neurodegeneration throughout the association cortex and limbic system, deposition of amyloid-β peptide (Aβ) in the neuropil and around the blood vessels, and formation of neurofibrillary tangles. The endopeptidase neprilysin has been successfully used to reduce the accumulation of Aβ following intracranial viral vector delivery or ex vivo manipulated intracranial delivery. These therapies have relied on direct injections into the brain, whereas a clinically desirable therapy would involve i.v. infusion of a recombinant enzyme. We previously characterized a recombinant neprilysin that contained a 38-amino acid brain-targeting domain. Recombinant cell lines have been generated expressing this brain-targeted enzyme (ASN12). In this report, we characterize the ASN12 recombinant protein for pharmacology in a mouse as well as efficacy in two APPtg mouse models of AD. The recombinant ASN12 transited to the brain with a t½ of 24 h and accumulated to 1.7% of injected dose at 24 h following i.v. delivery. We examined pharmacodynamics in the tg2576 APPtg mouse with the prion promoter APP695 SWE mutation and in the Line41 mThy1 APP751 mutation mouse. Treatment of either APPtg mouse resulted in reduced Aβ, increased neuronal synapses, and improved learning and memory. In addition, the Line41 APPtg mice showed increased levels of C-terminal neuropeptide Y fragments and increased neurogenesis. These results suggest that the recombinant brain-targeted neprilysin, ASN12, may be an effective treatment for AD and warrant further investigation in clinical trials. PMID:24825898

  20. A neuroprotective brain-penetrating endopeptidase fusion protein ameliorates Alzheimer disease pathology and restores neurogenesis.

    PubMed

    Spencer, Brian; Verma, Inder; Desplats, Paula; Morvinski, Dinorah; Rockenstein, Ed; Adame, Anthony; Masliah, Eliezer

    2014-06-20

    Alzheimer disease (AD) is characterized by widespread neurodegeneration throughout the association cortex and limbic system, deposition of amyloid-β peptide (Aβ) in the neuropil and around the blood vessels, and formation of neurofibrillary tangles. The endopeptidase neprilysin has been successfully used to reduce the accumulation of Aβ following intracranial viral vector delivery or ex vivo manipulated intracranial delivery. These therapies have relied on direct injections into the brain, whereas a clinically desirable therapy would involve i.v. infusion of a recombinant enzyme. We previously characterized a recombinant neprilysin that contained a 38-amino acid brain-targeting domain. Recombinant cell lines have been generated expressing this brain-targeted enzyme (ASN12). In this report, we characterize the ASN12 recombinant protein for pharmacology in a mouse as well as efficacy in two APPtg mouse models of AD. The recombinant ASN12 transited to the brain with a t½ of 24 h and accumulated to 1.7% of injected dose at 24 h following i.v. delivery. We examined pharmacodynamics in the tg2576 APPtg mouse with the prion promoter APP695 SWE mutation and in the Line41 mThy1 APP751 mutation mouse. Treatment of either APPtg mouse resulted in reduced Aβ, increased neuronal synapses, and improved learning and memory. In addition, the Line41 APPtg mice showed increased levels of C-terminal neuropeptide Y fragments and increased neurogenesis. These results suggest that the recombinant brain-targeted neprilysin, ASN12, may be an effective treatment for AD and warrant further investigation in clinical trials.

  1. Redox Proteomics Analysis to Decipher the Neurobiology of Alzheimer-like Neurodegeneration: Overlaps in Down Syndrome and Alzheimer Disease Brain

    PubMed Central

    Butterfield, D. Allan; Di Domenico, Fabio; Swomley, Aaron M.; Head, Elizabeth; Perluigi, Marzia

    2015-01-01

    Accumulation of oxidative damage is a common feature of neurodegeneration that together with mitochondrial dysfunction point to the fact that reactive oxygen species are major contributors to loss of neuronal homeostasis and cell death. Among several targets of oxidative stress, free radical-mediated damage to proteins is particularly important in aging and age-related neurodegenerative diseases. In the majority of cases, oxidative stress mediated post-translational modifications cause non-reversible modifications of protein structure that consistently lead to impaired function. Redox proteomics methods are powerful tools to unravel the complexity of neurodegeneration, by identifying brain proteins with oxidative post-translational modifications that are detrimental for protein function. The present review discusses the current literature showing evidence of impaired pathways linked to oxidative stress possibly involved in the neurodegenerative process leading to the development of Alzheimer-like dementia. In particular, we focus attention on dysregulated pathways that underlie neurodegeneration in both aging adults with Down syndrome (DS) and AD. Since AD pathology is age-dependent in DS and shows similarities with AD, identification of common oxidized proteins by redox proteomics in both DS and AD can improve our understanding of the overlapping mechanisms that lead from normal aging to development of AD. The most relevant proteomics findings highlight that disturbance of protein homeostasis and energy production are central mechanisms of neurodegeneration and overlap in aging DS and AD. Protein oxidation impacts crucial intracellular functions and may be considered a “leitmotif” of degenerating neurons. Therapeutic strategies aimed at preventing/reducing multiple components of processes leading to accumulation of oxidative damage will be critical in future studies. PMID:25242166

  2. Physical activity, body mass index, and brain atrophy in Alzheimer's disease.

    PubMed

    Boyle, Christina P; Raji, Cyrus A; Erickson, Kirk I; Lopez, Oscar L; Becker, James T; Gach, H Michael; Longstreth, W T; Teverovskiy, Leonid; Kuller, Lewis H; Carmichael, Owen T; Thompson, Paul M

    2015-01-01

    The purpose of this study was to use a novel imaging biomarker to assess associations between physical activity (PA), body mass index (BMI), and brain structure in normal aging, mild cognitive impairment, and Alzheimer's dementia. We studied 963 participants (mean age: 74.1 ± 4.4 years) from the multisite Cardiovascular Health Study including healthy controls (n = 724), Alzheimer's dementia patients (n = 104), and people with mild cognitive impairment (n = 135). Volumetric brain images were processed using tensor-based morphometry to analyze regional brain volumes. We regressed the local brain tissue volume on reported PA and computed BMI, and performed conjunction analyses using both variables. Covariates included age, sex, and study site. PA was independently associated with greater whole brain and regional brain volumes and reduced ventricular dilation. People with higher BMI had lower whole brain and regional brain volumes. A PA-BMI conjunction analysis showed brain preservation with PA and volume loss with increased BMI in overlapping brain regions. In one of the largest voxel-based cross-sectional studies to date, PA and lower BMI may be beneficial to the brain across the spectrum of aging and neurodegeneration.

  3. Longitudinal brain metabolic changes from amnestic mild cognitive impairment to Alzheimer's disease.

    PubMed

    Fouquet, Marine; Desgranges, Béatrice; Landeau, Brigitte; Duchesnay, Edouard; Mézenge, Florence; de la Sayette, Vincent; Viader, Fausto; Baron, Jean-Claude; Eustache, Francis; Chételat, Gaël

    2009-08-01

    A sensitive marker for monitoring progression of early Alzheimer's disease would help to develop and test new therapeutic strategies. The present study is aimed at investigating brain metabolism changes over time, as a potential monitoring marker, in patients with amnestic mild cognitive impairment, according to their clinical outcome (converters or non-converters), and in relation to their cognitive decline. Seventeen amnestic mild cognitive impairment patients underwent magnetic resonance imaging and 18FDG-positron emission tomography scans both at inclusion and 18 months later. Baseline and follow-up positron emission tomography data were corrected for partial volume effects and spatially normalized using magnetic resonance imaging data, scaled to the vermis and compared using SPM2. 'PET-PAC' maps reflecting metabolic per cent annual changes were created for correlation analyses with cognitive decline. In the whole sample, the greatest metabolic decrease concerned the posterior cingulate-precuneus area. Converters had significantly greater metabolic decrease than non-converters in two ventro-medial prefrontal areas, the subgenual (BA25) and anterior cingulate (BA24/32). PET-PAC in BA25 and BA24/32 combined allowed complete between-group discrimination. BA25 PET-PAC significantly correlated with both cognitive decline and PET-PAC in the hippocampal region and temporal pole, while BA24/32 PET-PAC correlated with posterior cingulate PET-PAC. Finally, the metabolic change in BA8/9/10 was inversely related to that in BA25 and showed relative increase with cognitive decline, suggesting that compensatory processes may occur in this dorso-medial prefrontal region. The observed ventro-medial prefrontal disruption is likely to reflect disconnection from the hippocampus, both indirectly through the cingulum bundle and posterior cingulate cortex for BA24/32, and directly through the uncinate fasciculus for BA25. Altogether, our findings emphasize the potential of 18FDG

  4. The Role of the Blood-Brain Barrier in the Pathogenesis of Senile Plaques in Alzheimer's Disease

    PubMed Central

    Provias, J.; Jeynes, B.

    2014-01-01

    The accumulation of beta-amyloid [Aβ] within senile plaques [SP] is characteristic of these lesions in Alzheimer's disease. The accumulation of Aβ42, in particular, in the superior temporal [ST] cortex may result from an inability of the blood brain barrier (BBB) to regulate the trans-endothelial transport and clearance of the amyloid. Lipoprotein receptor-related protein [LRP] and P-glycoprotein [P-gp] facilitate the efflux of Aβ out of the brain, whereas receptor for advanced glycation end products [RAGE] facilitates Aβ influx. Additionally, vascular endothelial growth factor [VEGF] and endothelial nitric oxide synthase [eNOS] may influence the trans-BBB transport of Aβ. In this study we examined ST samples and compared SP burden of all types with the capillary expression of LRP, p-gp, RAGE, VEGF, and e-NOS in samples from 15 control and 15 Alzheimer brains. LRP, P-gp, RAGE, VEGF, and eNOS positive capillaries and Aβ42 plaques were quantified and statistical analysis of the nonparametric data was performed using the Mann-Whitney and Kruskal-Wallis tests. In the Alzheimer condition P-gp, VEGF, and eNOS positive capillaries were negatively correlated with SP burden, but LRP and RAGE were positively correlated with SP burden. These results indicate altered BBB function in the pathogenesis of SPs in Alzheimer brains. PMID:25309772

  5. [Proceeding memory in Alzheimer's disease].

    PubMed

    Arroyo-Anlló, Eva Ma; Chamorro-Sánchez, Jorge; Díaz-Marta, Juan Poveda; Gil, Roger

    2013-01-01

    Procedural learning can acquire or develop skills through performance and repetition of a task unconsciously or unintentionally. Procedural skills are considered as the cornerstone in the neuropsychological rehabilitation to promote the autonomy of patients with brain damage, as those with Alzheimer's disease. This review presents data about procedural skills in Alzheimer's disease. Over the past three decades, we have found 40 articles studying various procedural skills in the Alzheimer's disease: motor, perceptual-motor, cognitive, perceptual-cognitive and those developed through serial reaction-time paradigm. We analyzed every study evaluating a procedural skill, indicating the used task and preservation or no preservation of procedural learning. Overall, most of the papers published describe conservation of learning procedures or relatively conserved in Alzheimer's disease, which could be used to promote patient autonomy.

  6. CFH Variants Affect Structural and Functional Brain Changes and Genetic Risk of Alzheimer's Disease.

    PubMed

    Zhang, Deng-Feng; Li, Jin; Wu, Huan; Cui, Yue; Bi, Rui; Zhou, He-Jiang; Wang, Hui-Zhen; Zhang, Chen; Wang, Dong; Kong, Qing-Peng; Li, Tao; Fang, Yiru; Jiang, Tianzi; Yao, Yong-Gang

    2016-03-01

    The immune response is highly active in Alzheimer's disease (AD). Identification of genetic risk contributed by immune genes to AD may provide essential insight for the prognosis, diagnosis, and treatment of this neurodegenerative disease. In this study, we performed a genetic screening for AD-related top immune genes identified in Europeans in a Chinese cohort, followed by a multiple-stage study focusing on Complement Factor H (CFH) gene. Effects of the risk SNPs on AD-related neuroimaging endophenotypes were evaluated through magnetic resonance imaging scan, and the effects on AD cerebrospinal fluid biomarkers (CSF) and CFH expression changes were measured in aged and AD brain tissues and AD cellular models. Our results showed that the AD-associated top immune genes reported in Europeans (CR1, CD33, CLU, and TREML2) have weak effects in Chinese, whereas CFH showed strong effects. In particular, rs1061170 (P(meta)=5.0 × 10(-4)) and rs800292 (P(meta)=1.3 × 10(-5)) showed robust associations with AD, which were confirmed in multiple world-wide sample sets (4317 cases and 16 795 controls). Rs1061170 (P=2.5 × 10(-3)) and rs800292 (P=4.7 × 10(-4)) risk-allele carriers have an increased entorhinal thickness in their young age and a higher atrophy rate as the disease progresses. Rs800292 risk-allele carriers have higher CSF tau and Aβ levels and severe cognitive decline. CFH expression level, which was affected by the risk-alleles, was increased in AD brains and cellular models. These comprehensive analyses suggested that CFH is an important immune factor in AD and affects multiple pathological changes in early life and during disease progress.

  7. CFH Variants Affect Structural and Functional Brain Changes and Genetic Risk of Alzheimer's Disease.

    PubMed

    Zhang, Deng-Feng; Li, Jin; Wu, Huan; Cui, Yue; Bi, Rui; Zhou, He-Jiang; Wang, Hui-Zhen; Zhang, Chen; Wang, Dong; Kong, Qing-Peng; Li, Tao; Fang, Yiru; Jiang, Tianzi; Yao, Yong-Gang

    2016-03-01

    The immune response is highly active in Alzheimer's disease (AD). Identification of genetic risk contributed by immune genes to AD may provide essential insight for the prognosis, diagnosis, and treatment of this neurodegenerative disease. In this study, we performed a genetic screening for AD-related top immune genes identified in Europeans in a Chinese cohort, followed by a multiple-stage study focusing on Complement Factor H (CFH) gene. Effects of the risk SNPs on AD-related neuroimaging endophenotypes were evaluated through magnetic resonance imaging scan, and the effects on AD cerebrospinal fluid biomarkers (CSF) and CFH expression changes were measured in aged and AD brain tissues and AD cellular models. Our results showed that the AD-associated top immune genes reported in Europeans (CR1, CD33, CLU, and TREML2) have weak effects in Chinese, whereas CFH showed strong effects. In particular, rs1061170 (P(meta)=5.0 × 10(-4)) and rs800292 (P(meta)=1.3 × 10(-5)) showed robust associations with AD, which were confirmed in multiple world-wide sample sets (4317 cases and 16 795 controls). Rs1061170 (P=2.5 × 10(-3)) and rs800292 (P=4.7 × 10(-4)) risk-allele carriers have an increased entorhinal thickness in their young age and a higher atrophy rate as the disease progresses. Rs800292 risk-allele carriers have higher CSF tau and Aβ levels and severe cognitive decline. CFH expression level, which was affected by the risk-alleles, was increased in AD brains and cellular models. These comprehensive analyses suggested that CFH is an important immune factor in AD and affects multiple pathological changes in early life and during disease progress. PMID:26243271

  8. Alzheimer's disease and type 2 diabetes-related alterations in brain mitochondria, autophagy and synaptic markers.

    PubMed

    Carvalho, Cristina; Santos, Maria S; Oliveira, Catarina R; Moreira, Paula I

    2015-08-01

    We aimed to investigate mitochondrial function, biogenesis and autophagy in the brain of type 2 diabetes (T2D) and Alzheimer's disease (AD) mice. Isolated brain mitochondria and homogenates from cerebral cortex and hippocampus of wild-type (WT), triple transgenic AD (3xTg-AD) and T2D mice were used to evaluate mitochondrial functional parameters and protein levels of mitochondrial biogenesis, autophagy and synaptic integrity markers, respectively. A significant decrease in mitochondrial respiration, membrane potential and energy levels was observed in T2D and 3xTg-AD mice. Also, a significant decrease in the levels of autophagy-related protein 7 (ATG7) and glycosylated lysosomal membrane protein 1 (LAMP1) was observed in cerebral cortex and hippocampus of T2D and 3xTg-AD mice. Moreover, both brain regions of 3xTg-AD mice present lower levels of nuclear respiratory factor (NRF) 1 while the levels of NRF2 are lower in both brain regions of T2D and 3xTg-AD mice. A decrease in mitochondrial encoded, nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) was also observed in T2D and 3xTg-AD mice although only statistically significant in T2D cortex. Furthermore, a decrease in the levels of postsynaptic density protein 95 (PSD95) in the cerebral cortex of 3xTg-AD mice and in hippocampus of T2D and 3xTg-AD mice and a decrease in the levels of synaptosomal-associated protein 25 (SNAP 25) in the hippocampus of T2D and 3xTg-AD mice were observed suggesting synaptic integrity loss. These results support the idea that alterations in mitochondrial function, biogenesis and autophagy cause synaptic damage in AD and T2D.

  9. Shotgun brain proteomics reveals early molecular signature in presymptomatic mouse model of Alzheimer's disease.

    PubMed

    Yang, Hongqian; Wittnam, Jessica L; Zubarev, Roman A; Bayer, Thomas A

    2013-01-01

    AβpE3-42 (N-terminal truncated amyloid-β peptide starting with pyroglutamate at the third position) is abundant in Alzheimer's disease (AD) brain and has high aggregation propensity and cellular toxicity. Transgenic TBA42 mice expressing AβpE3-42 exhibit a neurological phenotype evident at the age of 12 months. As AD has a long presymptomatic period, early detection of imminent neurodegeneration is highly desirable. In the present work we used four-month-old presymptomatic TBA42 mice and performed a whole-brain proteome analysis in order to elucidate early AD-related pathological changes and the molecular networks involved. At least three proteins were found to be moderately (by 17% to 28%) but statistically significantly upregulated, including: nectin-like molecule 1 involved in cell-cell adhesion; Homer proteins involved in scaffolding, organizing proteins at synapse and regulating intracellular calcium within neurons; and inositol-trisphosphate 3-kinase A, which is important for InsP3 induced calcium signaling in the brain. Analysis of key nodes (regulatory molecules found on pathway intersections) identified Rho-kinase (ROCK), a serine/threonine kinase and one of the major downstream effectors of the small GTPase Rho, as well as three key nodes of the mTOR/p70S6K signaling pathway previously implicated in multiple fundamental biological processes including synaptic plasticity, and upregulated in AD. These data confirm that AD-typical molecular pathways can be detected by whole-brain shotgun proteomics in young presymptomatic mice long before the onset of behavioral changes. PMID:24018289

  10. Patterns of regional brain hypometabolism associated with knowledge of semantic features and categories in Alzheimer's disease.

    PubMed

    Zahn, Roland; Garrard, Peter; Talazko, Jochen; Gondan, Matthias; Bubrowski, Philine; Juengling, Freimut; Slawik, Helen; Dykierek, Petra; Koester, Bernd; Hull, Michael

    2006-12-01

    The study of semantic memory in patients with Alzheimer's disease (AD) has raised important questions about the representation of conceptual knowledge in the human brain. It is still unknown whether semantic memory impairments are caused by localized damage to specialized regions or by diffuse damage to distributed representations within nonspecialized brain areas. To our knowledge, there have been no direct correlations of neuroimaging of in vivo brain function in AD with performance on tasks differentially addressing visual and functional knowledge of living and nonliving concepts. We used a semantic verification task and resting 18-fluorodeoxyglucose positron emission tomography in a group of mild to moderate AD patients to investigate this issue. The four task conditions required semantic knowledge of (1) visual, (2) functional properties of living objects, and (3) visual or (4) functional properties of nonliving objects. Visual property verification of living objects was significantly correlated with left posterior fusiform gyrus metabolism (Brodmann's area [BA] 37/19). Effects of visual and functional property verification for non-living objects largely overlapped in the left anterior temporal (BA 38/20) and bilateral premotor areas (BA 6), with the visual condition extending more into left lateral precentral areas. There were no associations with functional property verification for living concepts. Our results provide strong support for anatomically separable representations of living and nonliving concepts, as well as visual feature knowledge of living objects, and against distributed accounts of semantic memory that view visual and functional features of living and nonliving objects as distributed across a common set of brain areas. PMID:17129196

  11. Immunohistochemical analysis of human brain suggests pathological synergism of Alzheimer's disease and diabetes mellitus.

    PubMed

    Valente, Tony; Gella, Alejandro; Fernàndez-Busquets, Xavier; Unzeta, Mercedes; Durany, Nuria

    2010-01-01

    It has been extensively reported that diabetes mellitus (DM) patients have a higher risk of developing Alzheimer's disease (AD), but a mechanistic connection between both pathologies has not been provided so far. Carbohydrate-derived advanced glycation endproducts (AGEs) have been implicated in the chronic complications of DM and have been reported to play an important role in the pathogenesis of AD. The earliest histopathological manifestation of AD is the apparition of extracellular aggregates of the amyloid beta peptide (Abeta). To investigate possible correlations between AGEs and Abeta aggregates with both pathologies, we have performed an immuhistochemical study in human post-mortem samples of AD, AD with diabetes (ADD), diabetic and nondemented controls. ADD brains showed increased number of Abeta dense plaques and receptor for AGEs (RAGE)-positive and Tau-positive cells, higher AGEs levels and major microglial activation, compared to AD brain. Our results indicate that ADD patients present a significant increase of cell damage through a RAGE-dependent mechanism, suggesting that AGEs may promote the generation of an oxidative stress vicious cycle, which can explain the severe progression of patients with both pathologies.

  12. Aberrant protein phosphorylation in Alzheimer disease brain disturbs pro-survival and cell death pathways.

    PubMed

    Perluigi, M; Barone, E; Di Domenico, F; Butterfield, D A

    2016-10-01

    Protein phosphorylation of serine, threonine, and tyrosine residues is one of the most prevalent post-translational modifications fundamental in mediating diverse cellular functions in living cells. Aberrant protein phosphorylation is currently recognized as a critical step in the pathogenesis and progression of Alzheimer disease (AD). Changes in the pattern of protein phosphorylation of different brain regions are suggested to promote AD transition from a presymptomatic to a symptomatic state in response to accumulating amyloid β-peptide (Aβ). Several experimental approaches have been utilized to profile alteration of protein phosphorylation in the brain, including proteomics. Among central pathways regulated by kinases/phosphatases those involved in the activation/inhibition of both pro survival and cell death pathways play a central role in AD pathology. We discuss in detail how aberrant phosphorylation could contribute to dysregulate p53 activity and insulin-mediated signaling. Taken together these results highlight that targeted therapeutic intervention, which can restore phosphorylation homeostasis, either acting on kinases and phosphatases, conceivably may prove to be beneficial to prevent or slow the development and progression of AD.

  13. Glycosylation of microtubule-associated protein tau in Alzheimer's disease brain.

    PubMed

    Takahashi, M; Tsujioka, Y; Yamada, T; Tsuboi, Y; Okada, H; Yamamoto, T; Liposits, Z

    1999-06-01

    In the neurofibrillary pathology of Alzheimer's disease (AD), neurofibrillary tangles (NFTs) contain paired helical filaments (PHFs) as their major fibrous component. Abnormally hyperphosphorylated, microtubule-associated protein tau is the major protein subunit of PHFs. A recent in vitro study showed that PHF tangles from AD brains are highly glycosylated, whereas no glycan is detected in normal tau. Deglycosylation of PHF tangles converts them into bundles of straight filaments and restores their accessibility to microtubules. We showed that PHF tangles from AD brain tissue were associated with specific glycan molecules by double immunostaining with peroxidase and alkaline phosphatase labeling. Intracellular tangles and dystrophic neurites in a neuritic plaque with abnormally hyperphosphorylated tau, detected with the monoclonal antibodies AT-8 and anti-tau-2, were also positive with lectin Galanthus nivalis agglutinin (GNA) which recognizes both the N- and O-glycosidically linked saccharides. Colocalization was not seen in the extracellular tangles and amyloid deposition, suggesting that the glycosylation of tau might be associated with the early phase of insoluble NFT formation. Thus, although abnormal phosphorylation might promote aggregation of tau and inhibition of the assembly of microtubules, glycosylation mediated by a GNA-positive glycan appears to be responsible for the formation of the PHF structures in vivo.

  14. Aberrant protein phosphorylation in Alzheimer disease brain disturbs pro-survival and cell death pathways.

    PubMed

    Perluigi, M; Barone, E; Di Domenico, F; Butterfield, D A

    2016-10-01

    Protein phosphorylation of serine, threonine, and tyrosine residues is one of the most prevalent post-translational modifications fundamental in mediating diverse cellular functions in living cells. Aberrant protein phosphorylation is currently recognized as a critical step in the pathogenesis and progression of Alzheimer disease (AD). Changes in the pattern of protein phosphorylation of different brain regions are suggested to promote AD transition from a presymptomatic to a symptomatic state in response to accumulating amyloid β-peptide (Aβ). Several experimental approaches have been utilized to profile alteration of protein phosphorylation in the brain, including proteomics. Among central pathways regulated by kinases/phosphatases those involved in the activation/inhibition of both pro survival and cell death pathways play a central role in AD pathology. We discuss in detail how aberrant phosphorylation could contribute to dysregulate p53 activity and insulin-mediated signaling. Taken together these results highlight that targeted therapeutic intervention, which can restore phosphorylation homeostasis, either acting on kinases and phosphatases, conceivably may prove to be beneficial to prevent or slow the development and progression of AD. PMID:27425034

  15. Structure of heparan sulphate from human brain, with special regard to Alzheimer's disease.

    PubMed Central

    Lindahl, B; Eriksson, L; Lindahl, U

    1995-01-01

    Heparan sulphate (HS) was isolated after proteolytic digestion of cerebral cortex, obtained at autopsy, of patients with Alzheimer's disease (AD) and of control subjects. Deaminative cleavage in combination with selective radiolabelling procedures showed that the N-acetylated regions in the intact polysaccharides ranged from isolated residues to approximately 10 consecutive N-acetylated disaccharide units, without any apparent difference between AD and control HS. The yield of disaccharide deamination products was slightly higher with AD than with control HS, suggesting a differential distribution of N-sulphate groups. Separation of the disaccharides by anion-exchange h.p.l.c. yielded four mono-O-sulphated and one di-O-sulphated disaccharide; these components occurred in strikingly similar proportions in all cerebral HS preparations (except polysaccharide from neonatal brain) irrespective of the age of the individual and the histopathology of the cortex specimen. No significant difference was noted between HS obtained from control and from AD tissue. By contrast, the composition of HS isolated from brain differed significantly from that of HS preparations derived from other human organs. PMID:7864807

  16. Body mass index is associated with biological CSF markers of core brain pathology of Alzheimer's disease.

    PubMed

    Ewers, Michael; Schmitz, Susanne; Hansson, Oskar; Walsh, Cathal; Fitzpatrick, Annette; Bennett, David; Minthon, Lennart; Trojanowski, John Q; Shaw, Leslie M; Faluyi, Yetunde O; Vellas, Bruno; Dubois, Bruno; Blennow, Kaj; Buerger, Katharina; Teipel, Stefan J; Weiner, Michael; Hampel, Harald

    2012-08-01

    Weight changes are common in aging and Alzheimer's disease (AD) and postmortem findings suggest a relation between lower body mass index (BMI) and increased AD brain pathology. In the current multicenter study, we tested whether lower BMI is associated with higher core AD brain pathology as assessed by cerebrospinal fluid (CSF)-based biological markers of AD in 751 living subjects: 308 patients with AD, 296 subjects with amnestic mild cognitive impairment (MCI), and 147 elderly healthy controls (HC). Based upon a priori cutoff values on CSF concentration of total tau and beta-amyloid (Aβ(1-42)), subjects were binarized into a group with abnormal CSF biomarker signature (CSF+) and those without (CSF-). Results showed that BMI was significantly lower in the CSF+ when compared with the CSF- group (F = 27.7, df = 746, p < 0.001). There was no interaction between CSF signature and diagnosis or apolipoprotein E (ApoE) genotype. In conclusion, lower BMI is indicative of AD pathology as assessed with CSF-based biomarkers in demented and nondemented elderly subjects.

  17. Alzheimer's Disease

    MedlinePlus

    ... risk of urinary tract and other serious infections. Malnutrition or dehydration: People who have Alzheimer’s disease may ... swallow. It’s important to watch for signs of malnutrition. If you think that a loved one might ...

  18. Multifunctional liposomes reduce brain β-amyloid burden and ameliorate memory impairment in Alzheimer's disease mouse models.

    PubMed

    Balducci, Claudia; Mancini, Simona; Minniti, Stefania; La Vitola, Pietro; Zotti, Margherita; Sancini, Giulio; Mauri, Mario; Cagnotto, Alfredo; Colombo, Laura; Fiordaliso, Fabio; Grigoli, Emanuele; Salmona, Mario; Snellman, Anniina; Haaparanta-Solin, Merja; Forloni, Gianluigi; Masserini, Massimo; Re, Francesca

    2014-10-15

    Alzheimer's disease is characterized by the accumulation and deposition of plaques of β-amyloid (Aβ) peptide in the brain. Given its pivotal role, new therapies targeting Aβ are in demand. We rationally designed liposomes targeting the brain and promoting the disaggregation of Aβ assemblies and evaluated their efficiency in reducing the Aβ burden in Alzheimer's disease mouse models. Liposomes were bifunctionalized with a peptide derived from the apolipoprotein-E receptor-binding domain for blood-brain barrier targeting and with phosphatidic acid for Aβ binding. Bifunctionalized liposomes display the unique ability to hinder the formation of, and disaggregate, Aβ assemblies in vitro (EM experiments). Administration of bifunctionalized liposomes to APP/presenilin 1 transgenic mice (aged 10 months) for 3 weeks (three injections per week) decreased total brain-insoluble Aβ1-42 (-33%), assessed by ELISA, and the number and total area of plaques (-34%) detected histologically. Also, brain Aβ oligomers were reduced (-70.5%), as assessed by SDS-PAGE. Plaque reduction was confirmed in APP23 transgenic mice (aged 15 months) either histologically or by PET imaging with [(11)C]Pittsburgh compound B (PIB). The reduction of brain Aβ was associated with its increase in liver (+18%) and spleen (+20%). Notably, the novel-object recognition test showed that the treatment ameliorated mouse impaired memory. Finally, liposomes reached the brain in an intact form, as determined by confocal microscopy experiments with fluorescently labeled liposomes. These data suggest that bifunctionalized liposomes destabilize brain Aβ aggregates and promote peptide removal across the blood-brain barrier and its peripheral clearance. This all-in-one multitask therapeutic device can be considered as a candidate for the treatment of Alzheimer's disease. PMID:25319699

  19. Multifunctional Liposomes Reduce Brain β-Amyloid Burden and Ameliorate Memory Impairment in Alzheimer's Disease Mouse Models

    PubMed Central

    Balducci, Claudia; Mancini, Simona; Minniti, Stefania; La Vitola, Pietro; Zotti, Margherita; Sancini, Giulio; Mauri, Mario; Cagnotto, Alfredo; Colombo, Laura; Fiordaliso, Fabio; Grigoli, Emanuele; Salmona, Mario; Snellman, Anniina; Haaparanta-Solin, Merja; Forloni, Gianluigi; Re, Francesca

    2014-01-01

    Alzheimer's disease is characterized by the accumulation and deposition of plaques of β-amyloid (Aβ) peptide in the brain. Given its pivotal role, new therapies targeting Aβ are in demand. We rationally designed liposomes targeting the brain and promoting the disaggregation of Aβ assemblies and evaluated their efficiency in reducing the Aβ burden in Alzheimer's disease mouse models. Liposomes were bifunctionalized with a peptide derived from the apolipoprotein-E receptor-binding domain for blood–brain barrier targeting and with phosphatidic acid for Aβ binding. Bifunctionalized liposomes display the unique ability to hinder the formation of, and disaggregate, Aβ assemblies in vitro (EM experiments). Administration of bifunctionalized liposomes to APP/presenilin 1 transgenic mice (aged 10 months) for 3 weeks (three injections per week) decreased total brain-insoluble Aβ1–42 (−33%), assessed by ELISA, and the number and total area of plaques (−34%) detected histologically. Also, brain Aβ oligomers were reduced (−70.5%), as assessed by SDS-PAGE. Plaque reduction was confirmed in APP23 transgenic mice (aged 15 months) either histologically or by PET imaging with [11C]Pittsburgh compound B (PIB). The reduction of brain Aβ was associated with its increase in liver (+18%) and spleen (+20%). Notably, the novel-object recognition test showed that the treatment ameliorated mouse impaired memory. Finally, liposomes reached the brain in an intact form, as determined by confocal microscopy experiments with fluorescently labeled liposomes. These data suggest that bifunctionalized liposomes destabilize brain Aβ aggregates and promote peptide removal across the blood–brain barrier and its peripheral clearance. This all-in-one multitask therapeutic device can be considered as a candidate for the treatment of Alzheimer's disease. PMID:25319699

  20. Ultrasound Delivery of an Anti-Aβ Therapeutic Agent to the Brain in a Mouse Model of Alzheimer's Disease

    NASA Astrophysics Data System (ADS)

    Jordão, Jessica F.; Ayala-Grosso, Carlos A.; Chopra, Rajiv; McLaurin, JoAnne; Aubert, Isabelle; Hynynen, Kullervo

    2009-04-01

    Plaques composed of amyloid-beta (Aβ) peptides represent a pathological hallmark in the brain of patients with Alzheimer's disease. Aβ oligomers are considered cytotoxic and several therapeutic approaches focus on reducing Aβ load in the brain of Alzheimer's patients. The efficacy of most anti-Aβ agents is significantly limited because they do not cross the blood-brain-barrier. Innovative technologies capable of enhancing the permeability of the blood-brain barrier, thereby allowing entry of therapeutic agents into the brain, show great promise in circumventing this problem. The application of low-intensity focused ultrasound in the presence of an ultrasound contrast agent causes localized and transient permeability of the blood-brain barrier. We demonstrate the value of this technology for the delivery of anti-Aβ antibodies to the brain of TgCRND8 mice, a mouse model of Alzheimer's disease exhibiting Aβ plaques. BAM-10, an anti-Aβ antibody, was injected into the tail vein simultaneously with exposure to MRI-guided, low-intensity focused ultrasound (FUS) to one hemisphere of TgCNRD8 mice. Four hours after treatment, antibodies were detected at significant amounts only in the brain of mice receiving FUS in addition to BAM-10. This data provides a proof-of-concept that FUS allows anti-Aβ therapeutics to efficiently enter the brain and target Aβ plaques. Four days following a single treatment with BAM-10 and MRI-guided FUS, a significant decrease in the number of Aβ plaques on the side of the treated hemisphere was observed in TgCRND8 mice. In conclusion low-intensity, focused ultrasound is effective in delivering Aβ antibodies to the brain. This technology has the potential to enhance current anti-Aβ treatments by allowing increased exposure of amyloid plaques to treatment agents.

  1. Microwaves and Alzheimer's disease

    PubMed Central

    Zhang, Xia; Huang, Wen-Juan; Chen, Wei-Wei

    2016-01-01

    Alzheimer's diseases (AD) is the most common type of dementia and a neurodegenerative disease that occurs when the nerve cells in the brain die. The cause and treatment of AD remain unknown. However, AD is a disease that affects the brain, an organ that controls behavior. Accordingly, anything that can interact with the brain may affect this organ positively or negatively, thereby protecting or encouraging AD. In this regard, modern life encompasses microwaves for all issues including industrial, communications, medical and domestic tenders, and among all applications, the cell phone wave, which directly exposes the brain, continues to be the most used. Evidence suggests that microwaves may produce various biological effects on the central nervous system (CNS) and many arguments relay the possibility that microwaves may be involved in the pathophysiology of CNS disease, including AD. By contrast, previous studies have reported some beneficial cognitive effects and that microwaves may protect against cognitive impairment in AD. However, although many of the beneficial effects of microwaves are derived from animal models, but can easily be extrapolated to humans, whether microwaves cause AD is an important issue that is to be addressed in the current review. PMID:27698682

  2. Microwaves and Alzheimer's disease

    PubMed Central

    Zhang, Xia; Huang, Wen-Juan; Chen, Wei-Wei

    2016-01-01

    Alzheimer's diseases (AD) is the most common type of dementia and a neurodegenerative disease that occurs when the nerve cells in the brain die. The cause and treatment of AD remain unknown. However, AD is a disease that affects the brain, an organ that controls behavior. Accordingly, anything that can interact with the brain may affect this organ positively or negatively, thereby protecting or encouraging AD. In this regard, modern life encompasses microwaves for all issues including industrial, communications, medical and domestic tenders, and among all applications, the cell phone wave, which directly exposes the brain, continues to be the most used. Evidence suggests that microwaves may produce various biological effects on the central nervous system (CNS) and many arguments relay the possibility that microwaves may be involved in the pathophysiology of CNS disease, including AD. By contrast, previous studies have reported some beneficial cognitive effects and that microwaves may protect against cognitive impairment in AD. However, although many of the beneficial effects of microwaves are derived from animal models, but can easily be extrapolated to humans, whether microwaves cause AD is an important issue that is to be addressed in the current review.

  3. Blood–brain barrier dysfunction as a cause and consequence of Alzheimer's disease

    PubMed Central

    Erickson, Michelle A; Banks, William A

    2013-01-01

    The blood–brain barrier (BBB) plays critical roles in the maintenance of central nervous system (CNS) homeostasis. Dysfunction of the BBB occurs in a number of CNS diseases, including Alzheimer's disease (AD). A prevailing hypothesis in the AD field is the amyloid cascade hypothesis that states that amyloid-β (Aβ) deposition in the CNS initiates a cascade of molecular events that cause neurodegeneration, leading to AD onset and progression. In this review, the participation of the BBB in the amyloid cascade and in other mechanisms of AD neurodegeneration will be discussed. We will specifically focus on three aspects of BBB dysfunction: disruption, perturbation of transporters, and secretion of neurotoxic substances by the BBB. We will also discuss the interaction of the BBB with components of the neurovascular unit in relation to AD and the potential contribution of AD risk factors to aspects of BBB dysfunction. From the results discussed herein, we conclude that BBB dysfunction contributes to AD through a number of mechanisms that could be initiated in the presence or absence of Aβ pathology. PMID:23921899

  4. Longitudinal Changes in Functional Brain Connectivity Predicts Conversion to Alzheimer's Disease.

    PubMed

    Serra, Laura; Cercignani, Mara; Mastropasqua, Chiara; Torso, Mario; Spanò, Barbara; Makovac, Elena; Viola, Vanda; Giulietti, Giovanni; Marra, Camillo; Caltagirone, Carlo; Bozzali, Marco

    2016-01-01

    This longitudinal study investigates the modifications in structure and function occurring to typical Alzheimer's disease (AD) brains over a 2-year follow-up, from pre-dementia stages of disease, with the aim of identifying biomarkers of prognostic value. Thirty-one patients with amnestic mild cognitive impairment were recruited and followed-up with clinical, neuropsychological, and MRI assessments. Patients were retrospectively classified as AD Converters or Non-Converters, and the data compared between groups. Cross-sectional MRI data at baseline, assessing volume and functional connectivity abnormalities, confirmed previous findings, showing a more severe pattern of regional grey matter atrophy and default-mode network disconnection in Converters than in Non-Converters. Longitudinally, Converters showed more grey matter atrophy in the frontotemporal areas, accompanied by increased connectivity in the precuneus. Discriminant analysis revealed that functional connectivity of the precuneus within the default mode network at baseline is the parameter able to correctly classify patients in Converters and Non-Converters with high sensitivity, specificity, and accuracy.

  5. Type II fuzzy systems for amyloid plaque segmentation in transgenic mouse brains for Alzheimer's disease quantification

    NASA Astrophysics Data System (ADS)

    Khademi, April; Hosseinzadeh, Danoush

    2014-03-01

    Alzheimer's disease (AD) is the most common form of dementia in the elderly characterized by extracellular deposition of amyloid plaques (AP). Using animal models, AP loads have been manually measured from histological specimens to understand disease etiology, as well as response to treatment. Due to the manual nature of these approaches, obtaining the AP load is labourious, subjective and error prone. Automated algorithms can be designed to alleviate these challenges by objectively segmenting AP. In this paper, we focus on the development of a novel algorithm for AP segmentation based on robust preprocessing and a Type II fuzzy system. Type II fuzzy systems are much more advantageous over the traditional Type I fuzzy systems, since ambiguity in the membership function may be modeled and exploited to generate excellent segmentation results. The ambiguity in the membership function is defined as an adaptively changing parameter that is tuned based on the local contrast characteristics of the image. Using transgenic mouse brains with AP ground truth, validation studies were carried out showing a high degree of overlap and low degree of oversegmentation (0.8233 and 0.0917, respectively). The results highlight that such a framework is able to handle plaques of various types (diffuse, punctate), plaques with varying Aβ concentrations as well as intensity variation caused by treatment effects or staining variability.

  6. Expansion of the calcium hypothesis of brain aging and Alzheimer's disease: minding the store

    PubMed Central

    Thibault, Olivier; Gant, John C; Landfield, Philip W

    2007-01-01

    Evidence accumulated over more than two decades has implicated Ca2+ dysregulation in brain aging and Alzheimer's disease (AD), giving rise to the Ca2+ hypothesis of brain aging and dementia. Electrophysiological, imaging, and behavioral studies in hippocampal or cortical neurons of rodents and rabbits have revealed aging-related increases in the slow afterhyperpolarization, Ca2+ spikes and currents, Ca2+ transients, and L-type voltage-gated Ca2+ channel (L-VGCC) activity. Several of these changes have been associated with age-related deficits in learning or memory. Consequently, one version of the Ca2+ hypothesis has been that increased L-VGCC activity drives many of the other Ca2+-related biomarkers of hippocampal aging. In addition, other studies have reported aging- or AD model-related alterations in Ca2+ release from ryanodine receptors (RyR) on intracellular stores. The Ca2+-sensitive RyR channels amplify plasmalemmal Ca2+ influx by the mechanism of Ca2+-induced Ca2+ release (CICR). Considerable evidence indicates that a preferred functional link is present between L-VGCCs and RyRs which operate in series in heart and some brain cells. Here, we review studies implicating RyRs in altered Ca2+ regulation in cell toxicity, aging, and AD. A recent study from our laboratory showed that increased CICR plays a necessary role in the emergence of Ca2+-related biomarkers of aging. Consequently, we propose an expanded L-VGCC/Ca2+ hypothesis, in which aging/pathological changes occur in both L-type Ca2+ channels and RyRs, and interact to abnormally amplify Ca2+ transients. In turn, the increased transients result in dysregulation of multiple Ca2+-dependent processes and, through somewhat different pathways, in accelerated functional decline during aging and AD. PMID:17465978

  7. Who fans the flames of Alzheimer's disease brains? Misfolded tau on the crossroad of neurodegenerative and inflammatory pathways

    PubMed Central

    2012-01-01

    Neurodegeneration, induced by misfolded tau protein, and neuroinflammation, driven by glial cells, represent the salient features of Alzheimer's disease (AD) and related human tauopathies. While tau neurodegeneration significantly correlates with disease progression, brain inflammation seems to be an important factor in regulating the resistance or susceptibility to AD neurodegeneration. Previously, it has been shown that there is a reciprocal relationship between the local inflammatory response and neurofibrillary lesions. Numerous independent studies have reported that inflammatory responses may contribute to the development of tau pathology and thus accelerate the course of disease. It has been shown that various cytokines can significantly affect the functional and structural properties of intracellular tau. Notwithstanding, anti-inflammatory approaches have not unequivocally demonstrated that inhibition of the brain immune response can lead to reduction of neurofibrillary lesions. On the other hand, our recent data show that misfolded tau could represent a trigger for microglial activation, suggesting the dual role of misfolded tau in the Alzheimer's disease inflammatory cascade. On the basis of current knowledge, we can conclude that misfolded tau is located at the crossroad of the neurodegenerative and neuroinflammatory pathways. Thus disease-modified tau represents an important target for potential therapeutic strategies for patients with Alzheimer's disease. PMID:22397366

  8. Metamemory in Alzheimer's disease.

    PubMed

    Souchay, Céline

    2007-10-01

    Alois Alzheimer's first publication describes his patient's inability to be aware of her condition. One hundred years later, whether or not Alzheimer's disease (AD) patients show impaired awareness of their memory deficits is still of debate. This review makes a novel contribution, arguing that the ideal empirical tool to assess this question is the metamemory framework. The fact that the metamemory framework offers models of healthy memory and metamemory function and ready-developed measures mapped onto theoretical constructs, means that it is a useful paradigm to explore the question of memory awareness. The review focuses on two as yet separate approaches: the neuropsychological models of anosognosia as well as the metamemory framework. Metamemory constructs and measures are used to evaluate Alzheimer's patients' awareness of their memory difficulties by relating the main findings to the existing neuropsychological model of anosognosia. With this approach, only very specific deficits in awareness are found: a failure to update self-beliefs, and a deficit in monitoring episodic memory, possibly related to a deficit in effortful, conscious control processes. This review also considers how the exploration of the neural correlates of metamemory can help to draw novel hypotheses on the brain regions implicated in anosognosia in AD.

  9. Targeting brain α7 nicotinic acetylcholine receptors in Alzheimer's disease: rationale and current status.

    PubMed

    Vallés, Ana Sofía; Borroni, María Virginia; Barrantes, Francisco J

    2014-11-01

    Alzheimer's disease (AD) is the most common form of dementia among older persons. Pathognomonic hallmarks of the disease include the development of amyloid senile plaques and deposits of neurofibrillary tangles. These changes occur in the brain long before the clinical manifestations of AD (cognitive impairment in particular) become apparent. Nicotinic acetylcholine receptors (AChRs), particularly the α7 subtype, are highly expressed in brain regions relevant to cognitive and memory functions and involved in the processing of sensory information. There is strong evidence that implicates the participation of AChRs in AD. This review briefly introduces current strategies addressing the pathophysiologic findings (amyloid-β-peptide plaques, neurofibrillary tangles) and then focuses on more recent efforts of pharmacologic intervention in AD, specifically targeted to the α7 AChR. Whereas cholinesterase inhibitors such as donepezil, galantamine, or rivastigmine, together with the non-competitive N-methyl-D-aspartate receptor antagonist memantine are at the forefront of present-day clinical intervention for AD, new insights into AChR molecular pharmacology are bringing other drugs, directed at AChRs, to center stage. Among these are the positive allosteric modulators that selectively target α7 AChRs and are aimed at unleashing the factors that hinder agonist-mediated, α7 AChR channel activation. This calls for more detailed knowledge of the distribution, functional properties, and involvement of AChRs in various signaling cascades-together with the corresponding abnormalities in all these properties-to be able to engineer strategies in drug design and evaluate the therapeutic possibilities of new compounds targeting this class of neurotransmitter receptors. PMID:25248971

  10. The Effect of the APOE Genotype on Individual BrainAGE in Normal Aging, Mild Cognitive Impairment, and Alzheimer's Disease.

    PubMed

    Löwe, Luise Christine; Gaser, Christian; Franke, Katja

    2016-01-01

    In our aging society, diseases in the elderly come more and more into focus. An important issue in research is Mild Cognitive Impairment (MCI) and Alzheimer's Disease (AD) with their causes, diagnosis, treatment, and disease prediction. We applied the Brain Age Gap Estimation (BrainAGE) method to examine the impact of the Apolipoprotein E (APOE) genotype on structural brain aging, utilizing longitudinal magnetic resonance image (MRI) data of 405 subjects from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. We tested for differences in neuroanatomical aging between carrier and non-carrier of APOE ε4 within the diagnostic groups and for longitudinal changes in individual brain aging during about three years follow-up. We further examined whether a combination of BrainAGE and APOE status could improve prediction accuracy of conversion to AD in MCI patients. The influence of the APOE status on conversion from MCI to AD was analyzed within all allelic subgroups as well as for ε4 carriers and non-carriers. The BrainAGE scores differed significantly between normal controls, stable MCI (sMCI) and progressive MCI (pMCI) as well as AD patients. Differences in BrainAGE changing rates over time were observed for APOE ε4 carrier status as well as in the pMCI and AD groups. At baseline and during follow-up, BrainAGE scores correlated significantly with neuropsychological test scores in APOE ε4 carriers and non-carriers, especially in pMCI and AD patients. Prediction of conversion was most accurate using the BrainAGE score as compared to neuropsychological test scores, even when the patient's APOE status was unknown. For assessing the individual risk of coming down with AD as well as predicting conversion from MCI to AD, the BrainAGE method proves to be a useful and accurate tool even if the information of the patient's APOE status is missing. PMID:27410431

  11. Data on amyloid precursor protein accumulation, spontaneous physical activity, and motor learning after traumatic brain injury in the triple-transgenic mouse model of Alzheimer׳s disease.

    PubMed

    Kishimoto, Yasushi; Shishido, Hajime; Sawanishi, Mayumi; Toyota, Yasunori; Ueno, Masaki; Kubota, Takashi; Kirino, Yutaka; Tamiya, Takashi; Kawai, Nobuyuki

    2016-12-01

    This data article contains supporting information regarding the research article entitled "Traumatic brain injury accelerates amyloid-β deposition and impairs spatial learning in the triple-transgenic mouse model of Alzheimer׳s disease" (H. Shishido, Y. Kishimoto, N. Kawai, Y. Toyota, M. Ueno, T. Kubota, Y. Kirino, T. Tamiya, 2016) [1]. Triple-transgenic (3×Tg)-Alzheimer׳s disease (AD) model mice exhibited significantly poorer spatial learning than sham-treated 3×Tg-AD mice 28 days after traumatic brain injury (TBI). Correspondingly, amyloid-β (Aβ) deposition within the hippocampus was significantly greater in 3×Tg-AD mice 28 days after TBI. However, data regarding the short-term and long-term influences of TBI on amyloid precursor protein (APP) accumulation in AD model mice remain limited. Furthermore, there is little data showing whether physical activity and motor learning are affected by TBI in AD model mice. Here, we provide immunocytochemistry data confirming that TBI induces significant increases in APP accumulation in 3×Tg-AD mice at both 7 days and 28 days after TBI. Furthermore, 3×Tg-AD model mice exhibit a reduced ability to acquire conditioned responses (CRs) during delay eyeblink conditioning compared to sham-treated 3×Tg-AD model mice 28 days after TBI. However, physical activity and motor performance are not significantly changed in TBI-treated 3×Tg-AD model mice. PMID:27656663

  12. Data on amyloid precursor protein accumulation, spontaneous physical activity, and motor learning after traumatic brain injury in the triple-transgenic mouse model of Alzheimer׳s disease.

    PubMed

    Kishimoto, Yasushi; Shishido, Hajime; Sawanishi, Mayumi; Toyota, Yasunori; Ueno, Masaki; Kubota, Takashi; Kirino, Yutaka; Tamiya, Takashi; Kawai, Nobuyuki

    2016-12-01

    This data article contains supporting information regarding the research article entitled "Traumatic brain injury accelerates amyloid-β deposition and impairs spatial learning in the triple-transgenic mouse model of Alzheimer׳s disease" (H. Shishido, Y. Kishimoto, N. Kawai, Y. Toyota, M. Ueno, T. Kubota, Y. Kirino, T. Tamiya, 2016) [1]. Triple-transgenic (3×Tg)-Alzheimer׳s disease (AD) model mice exhibited significantly poorer spatial learning than sham-treated 3×Tg-AD mice 28 days after traumatic brain injury (TBI). Correspondingly, amyloid-β (Aβ) deposition within the hippocampus was significantly greater in 3×Tg-AD mice 28 days after TBI. However, data regarding the short-term and long-term influences of TBI on amyloid precursor protein (APP) accumulation in AD model mice remain limited. Furthermore, there is little data showing whether physical activity and motor learning are affected by TBI in AD model mice. Here, we provide immunocytochemistry data confirming that TBI induces significant increases in APP accumulation in 3×Tg-AD mice at both 7 days and 28 days after TBI. Furthermore, 3×Tg-AD model mice exhibit a reduced ability to acquire conditioned responses (CRs) during delay eyeblink conditioning compared to sham-treated 3×Tg-AD model mice 28 days after TBI. However, physical activity and motor performance are not significantly changed in TBI-treated 3×Tg-AD model mice.

  13. "A Culture-Brain Link: Negative Age Stereotypes Predict Alzheimer's Disease Biomarkers": Correction to Levy et al. (2016).

    PubMed

    2016-02-01

    Reports an error in "A Culture-Brain Link: Negative Age Stereotypes Predict Alzheimer's Disease Biomarkers" by Becca R. Levy, Luigi Ferrucci, Alan B. Zonderman, Martin D. Slade, Juan Troncoso and Susan M. Resnick (Psychology and Aging, Advanced Online Publication, Dec 7, 2015, np). In the article, the correct analyses were reported for bootstrapping; however, the sizes of the bootstrapping samples for Studies 1 and 2 were reversed. (The following abstract of the original article appeared in record 2015-54839-001.) Although negative age stereotypes have been found to predict adverse outcomes among older individuals, it was unknown whether the influence of stereotypes extends to brain changes associated with Alzheimer's disease. To consider this possibility, we drew on dementia-free participants, in the Baltimore Longitudinal Study of Aging, whose age stereotypes were assessed decades before yearly magnetic resonance images and brain autopsies were performed. Those holding more-negative age stereotypes earlier in life had significantly steeper hippocampal-volume loss and significantly greater accumulation of neurofibrillary tangles and amyloid plaques, adjusting for relevant covariates. These findings suggest a new pathway to identifying mechanisms and potential interventions related to the pathology of Alzheimer's disease.

  14. Optical fiber spectroscopy measures perfusion of the brain in a murine Alzheimer's disease model

    NASA Astrophysics Data System (ADS)

    Ahn, Hyung Jin; Strickland, Sidney; Krueger, James; Gareau, Daniel

    2014-02-01

    Optical fiber spectroscopy is a versatile tool for measuring diffuse reflectance and extracting absorption information that can noninvasively quantify the presence of chromophores such as oxyhemoglobin and deoxy-hemoglobin in tissues. Cerebrovascular abnormalities were widely recognized in Alzheimer's disease (AD) patients. We analyzed blood volume fraction and level of oxygenated hemoglobin in Tg6799 mice, which are transgenic mice expressing five different familial Alzheimer disease-associated mutations in the human amyloid precursor protein and presenilin-1 genes. Diffuse reflectance spectra were iteratively fit as weighted sums of oxy- and deoxy-hemoglobin. Our observations showed slightly hypoxic conditions and significantly increased blood volume in the Alzheimer's mice versus wild type. These results suggest that hyperperfusion of our AD mice may be a compensating mechanism for impaired cerebral vascular function and somehow relevant with early stage of AD patients. Ongoing work focuses on developing a cannula fixture that allows measurement in awake, behaving animals.

  15. Alzheimer Disease: Quantitative H-1 MR Spectroscopic Imaging of Frontoparietal Brain1

    PubMed Central

    Schuff, Norbert; Amend, Diane L.; Meyerhoff, Dieter J.; Tanabe, Jody L.; Norman, David; Fein, George; Weiner, Michael W.

    2009-01-01

    PURPOSE To replicate previous hydrogen-1 magnetic resonance (MR) spectroscopic imaging findings of metabolic abnormalities in patients with Alzheimer disease (AD), to verify that metabolic abnormalities are not an artifact of structural variations measured at MR imaging, to determine whether metabolic changes correlate with dementia severity, and to test whether MR imaging and MR spectroscopic imaging findings together improve ability to differentiate AD. MATERIALS AND METHODS MR spectroscopic imaging and MR imaging were performed in 28 patients with AD and 22 healthy elderly subjects. Spectroscopic imaging data were coregistered with MR imaging segmentation data to obtain volume-corrected metabolite concentrations. RESULTS Consistent with previous results, N-acetyl aspartate (NAA) levels were statistically significantly reduced in frontal and posterior mesial cortex of AD patients, presumably due to neuronal loss. NAA level reductions were independent of structural variations measured at MR imaging and, in parietal mesial cortex, were correlated mildly with dementia severity. Spectroscopic imaging findings of NAA level combined with MR imaging measures did not improve discrimination power for AD relative to that of MR imaging alone. CONCLUSION Reduced NAA levels in frontoparietal brain are of limited use for diagnosis of AD. However, they are not an artifact of structural variations and thus may provide useful information for the understanding of the pathologic processes underlying AD. PMID:9530304

  16. Lithium activates brain phospholipase A2 and improves memory in rats: implications for Alzheimer's disease.

    PubMed

    Mury, Fábio B; da Silva, Weber C; Barbosa, Nádia R; Mendes, Camila T; Bonini, Juliana S; Sarkis, Jorge Eduardo Souza; Cammarota, Martin; Izquierdo, Ivan; Gattaz, Wagner F; Dias-Neto, Emmanuel

    2016-10-01

    Phospholipase A2 (Pla2) is required for memory retrieval, and its inhibition in the hippocampus has been reported to impair memory acquisition in rats. Moreover, cognitive decline and memory deficits showed to be reduced in animal models after lithium treatment, prompting us to evaluate possible links between Pla2, lithium and memory. Here, we evaluated the possible modulation of Pla2 activity by a long-term treatment of rats with low doses of lithium and its impact in memory. Wistar rats were trained for the inhibitory avoidance task, treated with lithium for 100 days and tested for perdurability of long-term memory. Hippocampal samples were used for quantifying the expression of 19 brain-expressed Pla2 genes and for evaluating the enzymatic activity of Pla2 using group-specific radio-enzymatic assays. Our data pointed to a significant perdurability of long-term memory, which correlated with increased transcriptional and enzymatic activities of certain members of the Pla2 family (iPla2 and sPla2) after the chronic lithium treatment. Our data suggest new possible targets of lithium, add more information on its pharmacological activity and reinforce the possible use of low doses of lithium for the treatment of neurodegenerative conditions such as the Alzheimer's disease. PMID:26661385

  17. Voxel-based Morphometry of Brain MRI in Normal Aging and Alzheimer's Disease.

    PubMed

    Matsuda, Hiroshi

    2013-02-01

    Voxel-based morphometry (VBM) using structural brain MRI has been widely used for assessment of normal aging and Alzheimer's disease (AD). VBM of MRI data comprises segmentation into gray matter, white matter, and cerebrospinal fluid partitions, anatomical standardization of all the images to the same stereotactic space using linear affine transformation and further non-linear warping, smoothing, and finally performing a statistical analysis. Two techniques for VBM are commonly used, optimized VBM using statistical parametric mapping (SPM) 2 or SPM5 with non-linear warping based on discrete cosine transforms and SPM8 plus non-linear warping based on diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL). In normal aging, most cortical regions prominently in frontal and insular areas have been reported to show age-related gray matter atrophy. In contrast, specific structures such as amygdala, hippocampus, and thalamus have been reported to be preserved in normal aging. On the other hand, VBM studies have demonstrated progression of atrophy mapping upstream to Braak's stages of neurofibrillary tangle deposition in AD. The earliest atrophy takes place in medial temporal structures. Stand-alone VBM software using SPM8 plus DARTEL running on Windows has been newly developed as an adjunct to the clinical assessment of AD. This software provides a Z-score map as a consequence of comparison of a patient's MRI with a normal database. PMID:23423504

  18. Voxel-based Morphometry of Brain MRI in Normal Aging and Alzheimer's Disease.

    PubMed

    Matsuda, Hiroshi

    2013-02-01

    Voxel-based morphometry (VBM) using structural brain MRI has been widely used for assessment of normal aging and Alzheimer's disease (AD). VBM of MRI data comprises segmentation into gray matter, white matter, and cerebrospinal fluid partitions, anatomical standardization of all the images to the same stereotactic space using linear affine transformation and further non-linear warping, smoothing, and finally performing a statistical analysis. Two techniques for VBM are commonly used, optimized VBM using statistical parametric mapping (SPM) 2 or SPM5 with non-linear warping based on discrete cosine transforms and SPM8 plus non-linear warping based on diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL). In normal aging, most cortical regions prominently in frontal and insular areas have been reported to show age-related gray matter atrophy. In contrast, specific structures such as amygdala, hippocampus, and thalamus have been reported to be preserved in normal aging. On the other hand, VBM studies have demonstrated progression of atrophy mapping upstream to Braak's stages of neurofibrillary tangle deposition in AD. The earliest atrophy takes place in medial temporal structures. Stand-alone VBM software using SPM8 plus DARTEL running on Windows has been newly developed as an adjunct to the clinical assessment of AD. This software provides a Z-score map as a consequence of comparison of a patient's MRI with a normal database.

  19. Lithium activates brain phospholipase A2 and improves memory in rats: implications for Alzheimer's disease.

    PubMed

    Mury, Fábio B; da Silva, Weber C; Barbosa, Nádia R; Mendes, Camila T; Bonini, Juliana S; Sarkis, Jorge Eduardo Souza; Cammarota, Martin; Izquierdo, Ivan; Gattaz, Wagner F; Dias-Neto, Emmanuel

    2016-10-01

    Phospholipase A2 (Pla2) is required for memory retrieval, and its inhibition in the hippocampus has been reported to impair memory acquisition in rats. Moreover, cognitive decline and memory deficits showed to be reduced in animal models after lithium treatment, prompting us to evaluate possible links between Pla2, lithium and memory. Here, we evaluated the possible modulation of Pla2 activity by a long-term treatment of rats with low doses of lithium and its impact in memory. Wistar rats were trained for the inhibitory avoidance task, treated with lithium for 100 days and tested for perdurability of long-term memory. Hippocampal samples were used for quantifying the expression of 19 brain-expressed Pla2 genes and for evaluating the enzymatic activity of Pla2 using group-specific radio-enzymatic assays. Our data pointed to a significant perdurability of long-term memory, which correlated with increased transcriptional and enzymatic activities of certain members of the Pla2 family (iPla2 and sPla2) after the chronic lithium treatment. Our data suggest new possible targets of lithium, add more information on its pharmacological activity and reinforce the possible use of low doses of lithium for the treatment of neurodegenerative conditions such as the Alzheimer's disease.

  20. Lacosamide reduces HDAC levels in the brain and improves memory: Potential for treatment of Alzheimer's disease.

    PubMed

    Bang, Shraddha R; Ambavade, Shirishkumar D; Jagdale, Priti G; Adkar, Prafulla P; Waghmare, Arun B; Ambavade, Prashant D

    2015-07-01

    Lacosamide, a histone deacetylase (HDAC) inhibitor, has been approved for the treatment of epilepsy. Some HDAC inhibitors have been proven effective for the treatment of memory disorders. The present investigation was designed to evaluate the effect of lacosamide on memory and brain HDAC levels. The effect on memory was evaluated in animals with scopolamine-induced amnesia using the elevated plus maze, object recognition test, and radial arm maze. The levels of acetylcholinesterase and HDAC in the cerebral cortex were evaluated. Lacosamide at doses of 10 and 30mg/kg significantly reduced the transfer latency in the elevated plus maze. Lacosamide at a dose of 30mg/kg significantly increased the time spent with a familiar object in the object recognition test at the 24h interval and decreased the time spent in the baited arm. Moreover, at this dose, the number of errors in the radial arm maze at 3 and 24h intervals was minimized and a reduction in the level of HDAC1, but not acetylcholinesterase, was observed in the cerebral cortex. These effects of lacosamide are equivalent to those of piracetam at a dose of 300mg/kg. These results suggest that lacosamide at a 30mg/kg dose improves disrupted memory, possibly by inhibiting HDAC, and could be used to treat amnesic symptoms of Alzheimer's disease.

  1. Brain-Derived Neurotrophic Factor in Alzheimer's Disease: Risk, Mechanisms, and Therapy.

    PubMed

    Song, Jing-Hui; Yu, Jin-Tai; Tan, Lan

    2015-12-01

    Brain-derived neurotrophic factor (BDNF) has a neurotrophic support on neuron of central nervous system (CNS) and is a key molecule in the maintenance of synaptic plasticity and memory storage in hippocampus. However, changes of BDNF level and expression have been reported in the CNS as well as blood of Alzheimer's disease (AD) patients in the last decade, which indicates a potential role of BDNF in the pathogenesis of AD. Therefore, this review aims to summarize the latest progress in the field of BDNF and its biological roles in AD pathogenesis. We will discuss the interaction between BDNF and amyloid beta (Aβ) peptide, the effect of BDNF on synaptic repair in AD, and the association between BDNF polymorphism and AD risk. The most important is, enlightening the detailed biological ability and complicated mechanisms of action of BDNF in the context of AD would provide a future BDNF-related remedy for AD, such as increment in the production or release of endogenous BDNF by some drugs or BDNF mimics.

  2. Brain ERP components predict which individuals progress to Alzheimer's disease and which do not.

    PubMed

    Chapman, Robert M; McCrary, John W; Gardner, Margaret N; Sandoval, Tiffany C; Guillily, Maria D; Reilly, Lindsey A; DeGrush, Elizabeth

    2011-10-01

    Predicting which individuals will progress to Alzheimer's disease (AD) is important in both clinical and research settings. We used brain Event-Related Potentials (ERPs) obtained in a perceptual/cognitive paradigm with various processing demands to predict which individual Mild Cognitive Impairment (MCI) subjects will develop AD versus which will not. ERP components, including P3, memory "storage" component, and other earlier and later components, were identified and measured by Principal Components Analysis. When measured for particular task conditions, a weighted set of eight ERP component_conditions performed well in discriminant analysis at predicting later AD progression with good accuracy, sensitivity, and specificity. The predictions for most individuals (79%) had high posterior probabilities and were accurate (88%). This method, supported by a cross-validation where the prediction accuracy was 70-78%, features the posterior probability for each individual as a method of determining the likelihood of progression to AD. Empirically obtained prediction accuracies rose to 94% when the computed posterior probabilities for individuals were 0.90 or higher (which was found for 40% of our MCI sample).

  3. Expression and distribution of amyloid precursor protein-like protein-2 in Alzheimer's disease and in normal brain.

    PubMed Central

    Crain, B. J.; Hu, W.; Sze, C. I.; Slunt, H. H.; Koo, E. H.; Price, D. L.; Thinakaran, G.; Sisodia, S. S.

    1996-01-01

    Amyloid precursor-like protein-2 (APLP-2) belongs to a family of homologous amyloid precursor-like proteins. In the present study we report on the expression and distribution of APLP-2 in fetal and adult human brain and in brains of patients with Alzheimer's disease. We demonstrate that APLP-2 mRNAs encoding isoforms predicted to undergo post-translational modification by chondroitin sulfate glycosaminoglycans are elevated in fetal and aging brains relative to the brains of young adults. Immunocytochemical labeling with APLP-2-specific antibodies demonstrates APLP-2 immunoreactivity in cytoplasmic compartments in neurons and astrocytes, in large part overlapping the distribution of the amyloid precursor protein. In Alzheimer's disease brain, APLP-2 antibodies also label a subset of neuritic plaques. APLP-2 immunoreactivity is particularly conspicuous in large dystrophic neurites that also label with antibodies specific for APP and chromogranin A. In view of the age-dependent increase in levels of chondroitin sulfate glycosaminoglycan-modified forms of APLP-2 in aging brain and the accumulation of APLP-2 in dystrophic presynaptic elements, we suggest that APLP-2 may play roles in neuronal sprouting or in the aggregation, deposition, and/or persistence of beta-amyloid deposits. Images Figure 1 Figure 2 Figure 3 PMID:8863657

  4. Altered Neuroinflammation and Behavior after Traumatic Brain Injury in a Mouse Model of Alzheimer's Disease.

    PubMed

    Kokiko-Cochran, Olga; Ransohoff, Lena; Veenstra, Mike; Lee, Sungho; Saber, Maha; Sikora, Matt; Teknipp, Ryan; Xu, Guixiang; Bemiller, Shane; Wilson, Gina; Crish, Samuel; Bhaskar, Kiran; Lee, Yu-Shang; Ransohoff, Richard M; Lamb, Bruce T

    2016-04-01

    Traumatic brain injury (TBI) has acute and chronic sequelae, including an increased risk for the development of Alzheimer's disease (AD). TBI-associated neuroinflammation is characterized by activation of brain-resident microglia and infiltration of monocytes; however, recent studies have implicated beta-amyloid as a major manipulator of the inflammatory response. To examine neuroinflammation after TBI and development of AD-like features, these studies examined the effects of TBI in the presence and absence of beta-amyloid. The R1.40 mouse model of cerebral amyloidosis was used, with a focus on time points well before robust AD pathologies. Unexpectedly, in R1.40 mice, the acute neuroinflammatory response to TBI was strikingly muted, with reduced numbers of CNS myeloid cells acquiring a macrophage phenotype and decreased expression of inflammatory cytokines. At chronic time points, macrophage activation substantially declined in non-Tg TBI mice; however, it was relatively unchanged in R1.40 TBI mice. The persistent inflammatory response coincided with significant tissue loss between 3 and 120 days post-injury in R1.40 TBI mice, which was not observed in non-Tg TBI mice. Surprisingly, inflammatory cytokine expression was enhanced in R1.40 mice compared with non-Tg mice, regardless of injury group. Although R1.40 TBI mice demonstrated task-specific deficits in cognition, overall functional recovery was similar to non-Tg TBI mice. These findings suggest that accumulating beta-amyloid leads to an altered post-injury macrophage response at acute and chronic time points. Together, these studies emphasize the role of post-injury neuroinflammation in regulating long-term sequelae after TBI and also support recent studies implicating beta-amyloid as an immunomodulator.

  5. Pomegranate from Oman Alleviates the Brain Oxidative Damage in Transgenic Mouse Model of Alzheimer's disease

    PubMed Central

    Subash, Selvaraju; Essa, Musthafa Mohamed; Al-Asmi, Abdullah; Al-Adawi, Samir; Vaishnav, Ragini; Braidy, Nady; Manivasagam, Thamilarasan; Guillemin, Gilles J.

    2014-01-01

    Oxidative stress may play a key role in Alzheimer's disease (AD) neuropathology. Pomegranates (石榴 Shí Liú) contain very high levels of antioxidant polyphenolic substances, as compared to other fruits and vegetables. Polyphenols have been shown to be neuroprotective in different model systems. Here, the effects of the antioxidant-rich pomegranate fruit grown in Oman on brain oxidative stress status were tested in the AD transgenic mouse. The 4-month-old mice with double Swedish APP mutation (APPsw/Tg2576) were purchased from Taconic Farm, NY, USA. Four-month-old Tg2576 mice were fed with 4% pomegranate or control diet for 15 months and then assessed for the influence of diet on oxidative stress. Significant increase in oxidative stress was found in terms of enhanced levels of lipid peroxidation (LPO) and protein carbonyls. Concomitantly, decrease in the activities of antioxidant enzymes was observed in Tg2576 mice treated with control diet. Supplementation with 4% pomegranate attenuated oxidative damage, as evidenced by decreased LPO and protein carbonyl levels and restoration in the activities of the antioxidant enzymes [superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione (GSH), and Glutathione S transferase (GST)]. The activities of membrane-bound enzymes [Na+ K+-ATPase and acetylcholinesterase (AChE)] were altered in the brain regions of Tg2576 mouse treated with control diet, and 4% pomegranate supplementation was able to restore the activities of enzymes to comparable values observed in controls. The results suggest that the therapeutic potential of 4% pomegranate in the treatment of AD might be associated with counteracting the oxidative stress by the presence of active phytochemicals in it. PMID:25379464

  6. Traumatic Brain Injury Precipitates Cognitive Impairment and Extracellular Aβ Aggregation in Alzheimer's Disease Transgenic Mice

    PubMed Central

    Shimizu, Toru; Arendash, Gary W.; Borlongan, Cesar V.

    2013-01-01

    Traumatic brain injury (TBI) has become a signature wound of the wars in Iraq and Afghanistan. Many American soldiers, even those undiagnosed but likely suffering from mild TBI, display Alzheimer's disease (AD)-like cognitive impairments, suggesting a pathological overlap between TBI and AD. This study examined the cognitive and neurohistological effects of TBI in presymptomatic APP/PS1 AD-transgenic mice. AD mice and non-transgenic (NT) mice received an experimental TBI on the right parietal cortex using the controlled cortical impact model. Animals were trained in a water maze task for spatial memory before TBI, and then reevaluated in the same task at two and six weeks post-TBI. The results showed that AD mice with TBI made significantly more errors in the task than AD mice without TBI and NT mice regardless of TBI. A separate group of AD mice and NT mice were evaluated neurohistologically at six weeks after TBI. The number of extracellular beta-amyloid (Aβ)-deposits significantly increased by at least one fold in the cortex of AD mice that received TBI compared to the NT mice that received TBI or the AD and NT mice that underwent sham surgery. A significant decrease in MAP2 positive cells, indicating neuronal loss, was observed in the cortex of both the AD and NT mice that received TBI compared to the AD and NT mice subjected to sham surgery. Similar changes in extracellular Aβ deposits and MAP2 positive cells were also seen in the hippocampus. These results demonstrate for the first time that TBI precipitates cognitive impairment in presymptomatic AD mice, while also confirming extracellular Aβ deposits following TBI. The recognition of this pathological link between TBI and AD should aid in developing novel treatments directed at abrogating cellular injury and extracellular Aβ deposition in the brain. PMID:24223856

  7. Traumatic brain injury precipitates cognitive impairment and extracellular Aβ aggregation in Alzheimer's disease transgenic mice.

    PubMed

    Tajiri, Naoki; Kellogg, S Leilani; Shimizu, Toru; Arendash, Gary W; Borlongan, Cesar V

    2013-01-01

    Traumatic brain injury (TBI) has become a signature wound of the wars in Iraq and Afghanistan. Many American soldiers, even those undiagnosed but likely suffering from mild TBI, display Alzheimer's disease (AD)-like cognitive impairments, suggesting a pathological overlap between TBI and AD. This study examined the cognitive and neurohistological effects of TBI in presymptomatic APP/PS1 AD-transgenic mice. AD mice and non-transgenic (NT) mice received an experimental TBI on the right parietal cortex using the controlled cortical impact model. Animals were trained in a water maze task for spatial memory before TBI, and then reevaluated in the same task at two and six weeks post-TBI. The results showed that AD mice with TBI made significantly more errors in the task than AD mice without TBI and NT mice regardless of TBI. A separate group of AD mice and NT mice were evaluated neurohistologically at six weeks after TBI. The number of extracellular beta-amyloid (Aβ)-deposits significantly increased by at least one fold in the cortex of AD mice that received TBI compared to the NT mice that received TBI or the AD and NT mice that underwent sham surgery. A significant decrease in MAP2 positive cells, indicating neuronal loss, was observed in the cortex of both the AD and NT mice that received TBI compared to the AD and NT mice subjected to sham surgery. Similar changes in extracellular Aβ deposits and MAP2 positive cells were also seen in the hippocampus. These results demonstrate for the first time that TBI precipitates cognitive impairment in presymptomatic AD mice, while also confirming extracellular Aβ deposits following TBI. The recognition of this pathological link between TBI and AD should aid in developing novel treatments directed at abrogating cellular injury and extracellular Aβ deposition in the brain. PMID:24223856

  8. Proteomic profiling of brain cortex tissues in a Tau transgenic mouse model of Alzheimer's disease

    SciTech Connect

    Chang, Seong-Hun; Jung, In-Soo; Han, Gi-Yeon; Kim, Nam-Hee; Kim, Hyun-Jung; Kim, Chan-Wha

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer A transgenic mouse model expressing NSE-htau23 was used. Black-Right-Pointing-Pointer 2D-gel electrophoresis to analyze the cortex proteins of transgenic mice was used. Black-Right-Pointing-Pointer Differentially expressed spots in different stages of AD were identified. Black-Right-Pointing-Pointer GSTP1 and CAII were downregulated with the progression of AD. Black-Right-Pointing-Pointer SCRN1 and ATP6VE1 were up regulated and down regulated differentially. -- Abstract: Alzheimer's disease (AD) involves regionalized neuronal death, synaptic loss, and an accumulation of intracellular neurofibrillary tangles and extracellular senile plaques. Although there have been numerous studies on tau proteins and AD in various stages of neurodegenerative disease pathology, the relationship between tau and AD is not yet fully understood. A transgenic mouse model expressing neuron-specific enolase (NSE)-controlled human wild-type tau (NSE-htau23), which displays some of the typical Alzheimer-associated pathological features, was used to analyze the brain proteome associated with tau tangle deposition. Two-dimensional electrophoresis was performed to compare the cortex proteins of transgenic mice (6- and 12-month-old) with those of control mice. Differentially expressed spots in different stages of AD were identified with ESI-Q-TOF (electrospray ionization quadruple time-of-flight) mass spectrometry and liquid chromatography/tandem mass spectrometry. Among the identified proteins, glutathione S-transferase P 1 (GSTP1) and carbonic anhydrase II (CAII) were down-regulated with the progression of AD, and secerin-1 (SCRN1) and V-type proton ATPase subunit E 1 (ATP6VE1) were up-regulated only in the early stages, and down-regulated in the later stages of AD. The proteins, which were further confirmed by RT-PCR at the mRNA level and with western blotting at the protein level, are expected to be good candidates as drug targets for AD. The study

  9. [Alzheimer's disease and olfaction].

    PubMed

    Naudin, Marine; Mondon, Karl; Atanasova, Boriana

    2013-09-01

    Although olfactory disorders are not at the forefront of the clinical description of Alzheimer's disease (AD), they are common and often overlooked by clinicians and by patients who are largely unaware of their deficits. The past 30 years, the literature has shown early olfactory deficits in AD that is spreading across the olfactory spectrum with disease worsening. Partial overlap between brain areas implies both in olfaction and AD - especially limbic system - motivating these researches. This study describes olfactory parameters and tests using to investigate peripheral (odor threshold) and central (hedonicity, familiarity, intensity, discrimination, identification, olfactory memory) levels. Besides, this article takes an inventory of olfactory disorders in AD including odor threshold, discrimination, identification and olfactory memory capacities with controversial results observed in literature. At last, we discuss which type of olfactory dysfunction could have a clinical interest.

  10. Brain Substrates of Learning and Retention in Mild Cognitive Impairment Diagnosis and Progression to Alzheimer's Disease

    ERIC Educational Resources Information Center

    Chang, Yu-Ling; Bondi, Mark W.; Fennema-Notestine, Christine; McEvoy, Linda K.; Hagler, Donald J., Jr.; Jacobson, Mark W.; Dale, Anders M.

    2010-01-01

    Understanding the underlying qualitative features of memory deficits in mild cognitive impairment (MCI) can provide critical information for early detection of Alzheimer's disease (AD). This study sought to investigate the utility of both learning and retention measures in (a) the diagnosis of MCI, (b) predicting progression to AD, and (c)…

  11. Stress in the brain: novel cellular mechanisms of injury linked to Alzheimer's disease.

    PubMed

    Chong, Zhao Zhong; Li, Faqi; Maiese, Kenneth

    2005-07-01

    More than a century has elapsed since the description of Alois Alzheimer's patient Auguste D. Yet, the well-documented generation of beta-amyloid aggregates and neurofibrillary tangles that define Alzheimer's disease is believed to represent only a portion of the cellular processes that can determine the course of Alzheimer's disease. Understanding of the complex nature of this disorder has evolved with an increased appreciation for pathways that involve the generation of reactive oxygen species and oxidative stress, apoptotic injury that leads to nuclear degradation in both neuronal and vascular populations, and the early loss of cellular membrane asymmetry that mitigates inflammation and vascular occlusion. Recent work has identified novel pathways, such as the Wnt pathway and the serine-threonine kinase Akt, as central modulators that oversee cellular apoptosis and the formation of neurofibrillary tangles through their downstream substrates that include glycogen synthase kinase-3beta, Bad, and Bcl-xL. Other closely integrated pathways control microglial activation, release of inflammatory cytokines, and caspase and calpain activation for the processing of amyloid precursor protein, tau protein cleavage, and presenilin disposal. New therapeutic avenues that are just open to exploration, such as with nicotinamide adenine dinucleotide modulation, cell cycle modulation, metabotropic glutamate system modulation, and erythropoietin targeted expression, may provide both attractive and viable alternatives to treat Alzheimer's disease.

  12. Exploring Patterns of Alteration in Alzheimer's Disease Brain Networks: A Combined Structural and Functional Connectomics Analysis.

    PubMed

    Palesi, Fulvia; Castellazzi, Gloria; Casiraghi, Letizia; Sinforiani, Elena; Vitali, Paolo; Gandini Wheeler-Kingshott, Claudia A M; D'Angelo, Egidio

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a severe derangement of cognitive functions, primarily memory, in elderly subjects. As far as the functional impairment is concerned, growing evidence supports the "disconnection syndrome" hypothesis. Recent investigations using fMRI have revealed a generalized alteration of resting state networks (RSNs) in patients affected by AD and mild cognitive impairment (MCI). However, it was unclear whether the changes in functional connectivity were accompanied by corresponding structural network changes. In this work, we have developed a novel structural/functional connectomic approach: resting state fMRI was used to identify the functional cortical network nodes and diffusion MRI to reconstruct the fiber tracts to give a weight to internodal subcortical connections. Then, local and global efficiency were determined for different networks, exploring specific alterations of integration and segregation patterns in AD and MCI patients compared to healthy controls (HC). In the default mode network (DMN), that was the most affected, axonal loss, and reduced axonal integrity appeared to compromise both local and global efficiency along posterior-anterior connections. In the basal ganglia network (BGN), disruption of white matter integrity implied that main alterations occurred in local microstructure. In the anterior insular network (AIN), neuronal loss probably subtended a compromised communication with the insular cortex. Cognitive performance, evaluated by neuropsychological examinations, revealed a dependency on integration and segregation of brain networks. These findings are indicative of the fact that cognitive deficits in AD could be associated not only with cortical alterations (revealed by fMRI) but also with subcortical alterations (revealed by diffusion MRI) that extend beyond the areas primarily damaged by neurodegeneration, toward the support of an emerging concept of AD as a "disconnection

  13. Exploring Patterns of Alteration in Alzheimer's Disease Brain Networks: A Combined Structural and Functional Connectomics Analysis

    PubMed Central

    Palesi, Fulvia; Castellazzi, Gloria; Casiraghi, Letizia; Sinforiani, Elena; Vitali, Paolo; Gandini Wheeler-Kingshott, Claudia A. M.; D'Angelo, Egidio

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a severe derangement of cognitive functions, primarily memory, in elderly subjects. As far as the functional impairment is concerned, growing evidence supports the “disconnection syndrome” hypothesis. Recent investigations using fMRI have revealed a generalized alteration of resting state networks (RSNs) in patients affected by AD and mild cognitive impairment (MCI). However, it was unclear whether the changes in functional connectivity were accompanied by corresponding structural network changes. In this work, we have developed a novel structural/functional connectomic approach: resting state fMRI was used to identify the functional cortical network nodes and diffusion MRI to reconstruct the fiber tracts to give a weight to internodal subcortical connections. Then, local and global efficiency were determined for different networks, exploring specific alterations of integration and segregation patterns in AD and MCI patients compared to healthy controls (HC). In the default mode network (DMN), that was the most affected, axonal loss, and reduced axonal integrity appeared to compromise both local and global efficiency along posterior-anterior connections. In the basal ganglia network (BGN), disruption of white matter integrity implied that main alterations occurred in local microstructure. In the anterior insular network (AIN), neuronal loss probably subtended a compromised communication with the insular cortex. Cognitive performance, evaluated by neuropsychological examinations, revealed a dependency on integration and segregation of brain networks. These findings are indicative of the fact that cognitive deficits in AD could be associated not only with cortical alterations (revealed by fMRI) but also with subcortical alterations (revealed by diffusion MRI) that extend beyond the areas primarily damaged by neurodegeneration, toward the support of an emerging concept of AD as a

  14. Exploring Patterns of Alteration in Alzheimer's Disease Brain Networks: A Combined Structural and Functional Connectomics Analysis

    PubMed Central

    Palesi, Fulvia; Castellazzi, Gloria; Casiraghi, Letizia; Sinforiani, Elena; Vitali, Paolo; Gandini Wheeler-Kingshott, Claudia A. M.; D'Angelo, Egidio

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a severe derangement of cognitive functions, primarily memory, in elderly subjects. As far as the functional impairment is concerned, growing evidence supports the “disconnection syndrome” hypothesis. Recent investigations using fMRI have revealed a generalized alteration of resting state networks (RSNs) in patients affected by AD and mild cognitive impairment (MCI). However, it was unclear whether the changes in functional connectivity were accompanied by corresponding structural network changes. In this work, we have developed a novel structural/functional connectomic approach: resting state fMRI was used to identify the functional cortical network nodes and diffusion MRI to reconstruct the fiber tracts to give a weight to internodal subcortical connections. Then, local and global efficiency were determined for different networks, exploring specific alterations of integration and segregation patterns in AD and MCI patients compared to healthy controls (HC). In the default mode network (DMN), that was the most affected, axonal loss, and reduced axonal integrity appeared to compromise both local and global efficiency along posterior-anterior connections. In the basal ganglia network (BGN), disruption of white matter integrity implied that main alterations occurred in local microstructure. In the anterior insular network (AIN), neuronal loss probably subtended a compromised communication with the insular cortex. Cognitive performance, evaluated by neuropsychological examinations, revealed a dependency on integration and segregation of brain networks. These findings are indicative of the fact that cognitive deficits in AD could be associated not only with cortical alterations (revealed by fMRI) but also with subcortical alterations (revealed by diffusion MRI) that extend beyond the areas primarily damaged by neurodegeneration, toward the support of an emerging concept of AD as a

  15. Exploring Patterns of Alteration in Alzheimer's Disease Brain Networks: A Combined Structural and Functional Connectomics Analysis.

    PubMed

    Palesi, Fulvia; Castellazzi, Gloria; Casiraghi, Letizia; Sinforiani, Elena; Vitali, Paolo; Gandini Wheeler-Kingshott, Claudia A M; D'Angelo, Egidio

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a severe derangement of cognitive functions, primarily memory, in elderly subjects. As far as the functional impairment is concerned, growing evidence supports the "disconnection syndrome" hypothesis. Recent investigations using fMRI have revealed a generalized alteration of resting state networks (RSNs) in patients affected by AD and mild cognitive impairment (MCI). However, it was unclear whether the changes in functional connectivity were accompanied by corresponding structural network changes. In this work, we have developed a novel structural/functional connectomic approach: resting state fMRI was used to identify the functional cortical network nodes and diffusion MRI to reconstruct the fiber tracts to give a weight to internodal subcortical connections. Then, local and global efficiency were determined for different networks, exploring specific alterations of integration and segregation patterns in AD and MCI patients compared to healthy controls (HC). In the default mode network (DMN), that was the most affected, axonal loss, and reduced axonal integrity appeared to compromise both local and global efficiency along posterior-anterior connections. In the basal ganglia network (BGN), disruption of white matter integrity implied that main alterations occurred in local microstructure. In the anterior insular network (AIN), neuronal loss probably subtended a compromised communication with the insular cortex. Cognitive performance, evaluated by neuropsychological examinations, revealed a dependency on integration and segregation of brain networks. These findings are indicative of the fact that cognitive deficits in AD could be associated not only with cortical alterations (revealed by fMRI) but also with subcortical alterations (revealed by diffusion MRI) that extend beyond the areas primarily damaged by neurodegeneration, toward the support of an emerging concept of AD as a "disconnection

  16. Transcriptomics and mechanistic elucidation of Alzheimer's disease risk genes in the brain and in vitro models.

    PubMed

    Martiskainen, Henna; Viswanathan, Jayashree; Nykänen, Niko-Petteri; Kurki, Mitja; Helisalmi, Seppo; Natunen, Teemu; Sarajärvi, Timo; Kurkinen, Kaisa M A; Pursiheimo, Juha-Pekka; Rauramaa, Tuomas; Alafuzoff, Irina; Jääskeläinen, Juha E; Leinonen, Ville; Soininen, Hilkka; Haapasalo, Annakaisa; Huttunen, Henri J; Hiltunen, Mikko

    2015-02-01

    In this study, we have assessed the expression and splicing status of genes involved in the pathogenesis or affecting the risk of Alzheimer's disease (AD) in the postmortem inferior temporal cortex samples obtained from 60 subjects with varying degree of AD-related neurofibrillary pathology. These subjects were grouped based on neurofibrillary pathology into 3 groups: Braak stages 0-II, Braak stages III-IV, and Braak stages V-VI. We also examined the right frontal cortical biopsies obtained during life from 22 patients with idiopathic shunt-responding normal pressure hydrocephalus, a disease that displays similar pathologic alterations as seen in AD. These 22 patients were categorized according to dichotomized amyloid-β positive or negative pathology in the biopsies. We observed that the expression of FRMD4A significantly decreased, and the expression of MS4A6A significantly increased in relation to increasing AD-related neurofibrillary pathology. Moreover, the expression of 2 exons in both CLU and TREM2 significantly increased with increase in AD-related neurofibrillary pathology. However, a similar trend toward increased expression in CLU and TREM2 was observed with most of the studied exons, suggesting a global change in the expression rather than altered splicing. Correlation of gene expression with well-established AD-related factors, such as α-, β-, and γ-secretase activities, brain amyloid-β42 levels, and cerebrospinal fluid biomarkers, revealed a positive correlation between β-secretase activity and the expression of TREM2 and BIN1. In expression quantitative trait loci analysis, we did not detect significant effects of the risk alleles on gene expression or splicing. Analysis of the normal pressure hydrocephalus biopsies revealed no differences in the expression or splicing profiles of the studied genes between amyloid-β positive and negative patients. Using the protein-protein interaction-based in vitro pathway analysis tools, we found that

  17. Poly(n-butylcyanoacrylate) nanoparticles coated with polysorbate 80 for the targeted delivery of rivastigmine into the brain to treat Alzheimer's disease.

    PubMed

    Wilson, Barnabas; Samanta, Malay Kumar; Santhi, Kumaraswamy; Kumar, Kokilampal Perumal Sampath; Paramakrishnan, Nallupillai; Suresh, Bhojraj

    2008-03-20

    Alzheimer's disease is a progressive and fatal neurodegenerative disorder manifested by cognitive and memory deterioration, progressive impairment of activities of daily living, and a variety of neuropsychiatric symptoms and behavioral disturbances. Alzheimer's disease affects 15 million people worldwide and it has been estimated that Alzheimer's disease affects 4.5 million Americans. Rivastigmine is a reversible cholinesterase inhibitor used for the treatment of Alzheimer's disease. Central nervous system drug efficacy depends upon the ability of a drug to cross the blood-brain barrier and reach therapeutic concentrations in brain following systemic administration. The clinical failures of most of the potentially effective therapeutics to treat the central nervous system disorders are often not due to a lack of drug potency but rather shortcomings in the method by which the drug is delivered. Hence, considering the importance of treating Alzheimer's disease, we made an attempt to target the anti-Alzheimer's drug rivastigmine in the brain by using poly(n-butylcyanoacrylate) nanoparticles. The drug was administered as a free drug, bound to nanoparticles and also bound to nanoparticles coated with polysorbate 80. In the brain a significant increase in rivastigmine uptake was observed in the case of poly(n-butylcyanoacrylate) nanoparticles coated with 1% polysorbate 80 compared to the free drug. In conclusion that the present study demonstrates that the brain concentration of intravenously injected rivastigmine can be enhanced over 3.82 fold by binding to poly(n-butylcyanoacrylate) nanoparticles coated with 1% nonionic surfactant polysorbate 80.

  18. Impairment of biliverdin reductase-A promotes brain insulin resistance in Alzheimer disease: A new paradigm.

    PubMed

    Barone, Eugenio; Di Domenico, Fabio; Cassano, Tommaso; Arena, Andrea; Tramutola, Antonella; Lavecchia, Michele Angelo; Coccia, Raffaella; Butterfield, D Allan; Perluigi, Marzia

    2016-02-01

    Clinical studies suggest a link between peripheral insulin resistance and cognitive dysfunction. Interestingly, post-mortem analyses of Alzheimer disease (AD) subjects demonstrated insulin resistance in the brain proposing a role for cognitive deficits observed in AD. However, the mechanisms responsible for the onset of brain insulin resistance (BIR) need further elucidations. Biliverdin reductase-A (BVR-A) emerged as a unique Ser/Thr/Tyr kinase directly involved in the insulin signaling and represents an up-stream regulator of the insulin signaling cascade. Because we previously demonstrated the oxidative stress (OS)-induced impairment of BVR-A in human AD brain, we hypothesize that BVR-A dysregulation could be associated with the onset of BIR in AD. In the present work, we longitudinally analyze the age-dependent changes of (i) BVR-A protein levels and activation, (ii) total oxidative stress markers levels (PC, HNE, 3-NT) as well as (iii) IR/IRS1 levels and activation in the hippocampus of the triple transgenic model of AD (3xTg-AD) mice. Furthermore, ad hoc experiments have been performed in SH-SY5Y neuroblastoma cells to clarify the molecular mechanism(s) underlying changes observed in mice. Our results show that OS-induced impairment of BVR-A kinase activity is an early event, which starts prior the accumulation of Aβ and tau pathology or the elevation of TNF-α, and that greatly contribute to the onset of BIR along the progression of AD pathology in 3xTg-Ad mice. Based on these evidence we, therefore, propose a new paradigm for which: OS-induced impairment of BVR-A is firstly responsible for a sustained activation of IRS1, which then causes the stimulation of negative feedback mechanisms (i.e. mTOR) aimed to turn-off IRS1 hyper-activity and thus BIR. Similar alterations characterize also the normal aging process in mice, positing BVR-A impairment as a possible bridge in the transition from normal aging to AD. PMID:26698666

  19. Brain structure and function related to cognitive reserve variables in normal aging, mild cognitive impairment and Alzheimer's disease.

    PubMed

    Solé-Padullés, Cristina; Bartrés-Faz, David; Junqué, Carme; Vendrell, Pere; Rami, Lorena; Clemente, Imma C; Bosch, Beatriu; Villar, Amparo; Bargalló, Núria; Jurado, M Angeles; Barrios, Maite; Molinuevo, Jose Luis

    2009-07-01

    Cognitive reserve (CR) is the brain's capacity to cope with cerebral damage to minimize clinical manifestations. The 'passive model' considers head or brain measures as anatomical substrates of CR, whereas the 'active model' emphasizes the use of brain networks effectively. Sixteen healthy subjects, 12 amnestic mild cognitive impairment (MCI) and 16 cases with mild Alzheimer's disease (AD) were included to investigate the relationships between proxies of CR and cerebral measures considered in the 'passive' and 'active' models. CR proxies were inferred premorbid IQ (WAIS Vocabulary test), 'education-occupation', a questionnaire of intellectual and social activities and a composite CR measure. MRI-derived whole-brain volumes and brain activity by functional MRI during a visual encoding task were obtained. Among healthy elders, higher CR was related to larger brains and reduced activity during cognitive processing, suggesting more effective use of cerebral networks. In contrast, higher CR was associated with reduced brain volumes in MCI and AD and increased brain function in the latter, indicating more advanced neuropathology but that active compensatory mechanisms are still at work in higher CR patients. The right superior temporal gyrus (BA 22) and the left superior parietal lobe (BA 7) showed greatest significant differences in direction of slope with CR and activation between controls and AD cases. Finally, a regression analysis revealed that fMRI patterns were more closely related to CR proxies than brain volumes. Overall, inverse relationships for healthy and pathological aging groups emerged between brain structure and function and CR variables. PMID:18053618

  20. Acute aerobic exercise increases brain-derived neurotrophic factor levels in elderly with Alzheimer's disease.

    PubMed

    Coelho, Flávia Gomes de Melo; Vital, Thays Martins; Stein, Angelica Miki; Arantes, Franciel José; Rueda, André Veloso; Camarini, Rosana; Teodorov, Elizabeth; Santos-Galduróz, Ruth Ferreira

    2014-01-01

    Studies indicate the involvement of brain-derived neurotrophic factor (BDNF) in the pathogenesis of Alzheimer's disease (AD). Decreased BDNF levels may constitute a lack of trophic support and contribute to cognitive impairment in AD. The benefits of acute and chronic physical exercise on BDNF levels are well-documented in humans, however, exercise effects on BDNF levels have not been analyzed in older adults with AD. The aim of this study was to investigate the effects of acute aerobic exercise on BDNF levels in older adults with AD and to verify associations among BDNF levels, aerobic fitness, and level of physical activity. Using a controlled design, twenty-one patients with AD (76.3 ± 6.2 years) and eighteen healthy older adults (74.6 ± 4.7 years) completed an acute aerobic exercise. The outcomes included measures of BDNF plasma levels, aerobic fitness (treadmill grade, time to exhaustion, VO2, and maximal lactate) and level of physical activity (Baecke Questionnaire Modified for the Elderly). The independent t-test shows differences between groups with respect to the BDNF plasma levels at baseline (p = 0.04; t = 4.53; df = 37). In two-way ANOVA, a significant effect of time was found (p = 0.001; F = 13.63; df = 37), the aerobic exercise significantly increased BDNF plasma levels in AD patients and healthy controls. A significant correlation (p = 0.04; r = 0.33) was found between BDNF levels and the level of physical activity. The results of our study suggest that aerobic exercise increases BDNF plasma levels in patients with AD and healthy controls. In addition to that, BDNF levels had association with level of physical activity.

  1. Functional brain networks in Alzheimer's disease: EEG analysis based on limited penetrable visibility graph and phase space method

    NASA Astrophysics Data System (ADS)

    Wang, Jiang; Yang, Chen; Wang, Ruofan; Yu, Haitao; Cao, Yibin; Liu, Jing

    2016-10-01

    In this paper, EEG series are applied to construct functional connections with the correlation between different regions in order to investigate the nonlinear characteristic and the cognitive function of the brain with Alzheimer's disease (AD). First, limited penetrable visibility graph (LPVG) and phase space method map single EEG series into networks, and investigate the underlying chaotic system dynamics of AD brain. Topological properties of the networks are extracted, such as average path length and clustering coefficient. It is found that the network topology of AD in several local brain regions are different from that of the control group with no statistically significant difference existing all over the brain. Furthermore, in order to detect the abnormality of AD brain as a whole, functional connections among different brain regions are reconstructed based on similarity of clustering coefficient sequence (CCSS) of EEG series in the four frequency bands (delta, theta, alpha, and beta), which exhibit obvious small-world properties. Graph analysis demonstrates that for both methodologies, the functional connections between regions of AD brain decrease, particularly in the alpha frequency band. AD causes the graph index complexity of the functional network decreased, the small-world properties weakened, and the vulnerability increased. The obtained results show that the brain functional network constructed by LPVG and phase space method might be more effective to distinguish AD from the normal control than the analysis of single series, which is helpful for revealing the underlying pathological mechanism of the disease.

  2. Imaging the earliest stages of Alzheimer's disease.

    PubMed

    Wu, William; Small, Scott A

    2006-12-01

    Historical progress in medicine can be charted along the lines of technical innovations that have visualized the invisible. One hundred years ago, Alois Alzheimer exploited newly developed histological stains to visualize his eponymonous disease in dead tissue under the microscope. Now, as we are entering the second century of Alzheimer's disease research, technical innovation has endowed us with a range of in vivo imaging techniques that promise to visualize Alzheimer' disease in living people. The earliest stage of Alzheimer's disease is characterized by cell-sickness, not cell-death, and can occur before the deposition of amyloid plaques or neurofibrillary tangles. In principle, 'functional' imaging techniques might be able to detect this early stage of the disease, a stage that was invisible to Alzheimer himself. Here, we will first define the neurobiological meaning of 'function' and then review the different approaches that measure brain dysfunction in Alzheimer' disease.

  3. Stroke risk interacts with Alzheimer's disease biomarkers on brain aging outcomes.

    PubMed

    Hohman, Timothy J; Samuels, Lauren R; Liu, Dandan; Gifford, Katherine A; Mukherjee, Shubhabrata; Benson, Elleena M; Abel, Ty; Ruberg, Frederick L; Jefferson, Angela L

    2015-09-01

    Alzheimer's disease (AD) biomarkers and stroke risk factors independently predict cognitive impairment, likely through independent disease pathways. However, limited work has sought to describe the dynamic interplay between these important risk factors. This article evaluated the interaction between stroke risk and AD biomarkers on hippocampal volume and cognitive performance. We first evaluated the interaction between stroke risk factors and AD biomarkers using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI, n = 1202). We then extended our findings to an independent autopsy data set from the National Alzheimer's Coordinating Center (NACC, n = 1122) using measures of AD pathology. Stroke risk was quantified using the Framingham Stroke Risk Profile. In ADNI, stroke risk interacted with tau and amyloid levels in relation to baseline and longitudinal cognitive performance. Similarly, in NACC, stroke risk interacted with amyloid and tau positivity on cognitive performance. The effect of stroke risk factors on cognition was strongest in the absence of AD biomarkers or neuropathology, providing additional evidence that AD biomarkers and stroke risk factors relate to cognition through independent pathways.

  4. Can ketones compensate for deteriorating brain glucose uptake during aging? Implications for the risk and treatment of Alzheimer's disease.

    PubMed

    Cunnane, Stephen C; Courchesne-Loyer, Alexandre; St-Pierre, Valérie; Vandenberghe, Camille; Pierotti, Tyler; Fortier, Mélanie; Croteau, Etienne; Castellano, Christian-Alexandre

    2016-03-01

    Brain glucose uptake is impaired in Alzheimer's disease (AD). A key question is whether cognitive decline can be delayed if this brain energy defect is at least partly corrected or bypassed early in the disease. The principal ketones (also called ketone bodies), β-hydroxybutyrate and acetoacetate, are the brain's main physiological alternative fuel to glucose. Three studies in mild-to-moderate AD have shown that, unlike with glucose, brain ketone uptake is not different from that in healthy age-matched controls. Published clinical trials demonstrate that increasing ketone availability to the brain via moderate nutritional ketosis has a modest beneficial effect on cognitive outcomes in mild-to-moderate AD and in mild cognitive impairment. Nutritional ketosis can be safely achieved by a high-fat ketogenic diet, by supplements providing 20-70 g/day of medium-chain triglycerides containing the eight- and ten-carbon fatty acids octanoate and decanoate, or by ketone esters. Given the acute dependence of the brain on its energy supply, it seems reasonable that the development of therapeutic strategies aimed at AD mandates consideration of how the underlying problem of deteriorating brain fuel supply can be corrected or delayed. PMID:26766547

  5. Autotoxicity and Alzheimer disease.

    PubMed

    McGeer, P L; McGeer, E G

    2000-06-01

    I mmunological responses are considered to be either humoral, resulting from cloning of B lymphocytes, or cell mediated, resulting from cloning of T lymphocytes. Autoimmune diseases occur when the cloned products attack host tissue. Inflammation is considered a nonspecific response to injury, characterized by exudation of serum into damaged tissue, and identified by the cardinal signs of rubor, calor, dolor, and tumor. However, these classic mechanisms do not fit pathological observations of Alzheimer disease (AD)-affected brain tissue. Although many of the components prominently associated with peripheral immunological and inflammatory states are present in AD lesions, there are no identifiable B lymphocytes or antibodies, and T cells are sparse. Furthermore, the blood-brain barrier is intact, excluding exudation of exogenous serum proteins. Although "neuroinflammation" is the term commonly used to describe the pathological changes, it fails to define adequately the process that is taking place. The reaction is neither a nonspecific response to injury, as classically implied for inflammatory reactions, nor an autoimmune reaction, despite the directed attack against plaques and extracellular tangles. It is most appropriately defined as an innate immunoreaction. The fact that such a reaction can be mounted by brain, an organ frequently described as being immunologically privileged, suggests that a reevaluation is required of the dimensions of the innate immune system, including how it operates at the tissue level. The innate immune system is primitive, while the adaptive immune system, which is directed by peripheral immune organs, is an invention of vertebrates. Even in vertebrates, however, the innate immune system is the first line of defense. Much more needs to be learned about the operation of the innate immune system in health and disease. Arch Neurol. 2000.

  6. Hg sup 2+ induces GTP-tubulin interactions in rat brain similar to those observed in Alzheimer's disease

    SciTech Connect

    Duhr, E.; Pendergrass, C.; Kasarskis, E.; Slevin, J.; Haley, B. )

    1991-03-11

    The pathogenesis of Alzheimer's Disease (AD) is unknown. Using SDS-PAGE and autoradiography the authors' laboratory has shown: (1) that the tubulin in AD brain is less photolabeled by ({sup 32}P)8N{sub 3}GTP than is tubulin from control brain and (2) that low {mu}M levels of preformed Hg{sup 2+}EDTA specifically blocked interactions of tubulin-({sup 32}P)8N{sub 3}GTP in control human brain homogenates giving a photolabeling profile identical to AD brain. Elevated levels of Hg{sup 2+} have been reported in AD brain by others. Earlier work using ({sup 32}P)8N{sub 3}GTP with Al{sup 3+} treated rat and rabbit brain showed no differences from control with regards to tubulin photolabeling. However, our latest data show that brain samples from Hg{sup 2+} fed rats display an abolished GTP-tubulin interaction similar to AD brain samples as determined by ({sup 32}P)8N{sub 3}GTP photolabeling profiles. Removal of Hg{sup 2+} from treated rats did not reverse the effect. These results suggest that certain complexed forms of Hg{sup 2+} must be considered as a potential source for the etiology of AD.

  7. [Brain imaging of Alzheimer' disease: state of the art and perspectives for clinicians].

    PubMed

    Trombella, Sara; Assal, Frédéric; Zekry, Dina; Gold, Gabriel; Giannakopoulos, Panteleimon; Garibotto, Valentina; Démonet, Jean-François; Frisoni, Giovanni B

    2016-04-20

    To improve the clinical detection of Alzheimer's disease (AD) new diagnostic criteria have been proposed, based on biomarkers of synaptic dysfunction, AD-related neurodegeneration, and Aβ cerebral amyloidosis. Magnetic resonance imaging (MRI) and position emission tomography (PET) neuroimaging can be configured as powerful means for the detection of medial-temporal atrophy, reduced uptake of 18F-FDG PET or and increased retention of Aβ amyloid protein by amyloïd-PET. In this review, we will discuss these promising techniques that allow assessing in vivo AD pathology and help clinicians to better diagnose and follow-up patients, particularly in clinical trials using disease-modifying treatments.

  8. [Brain imaging of Alzheimer' disease: state of the art and perspectives for clinicians].

    PubMed

    Trombella, Sara; Assal, Frédéric; Zekry, Dina; Gold, Gabriel; Giannakopoulos, Panteleimon; Garibotto, Valentina; Démonet, Jean-François; Frisoni, Giovanni B

    2016-04-20

    To improve the clinical detection of Alzheimer's disease (AD) new diagnostic criteria have been proposed, based on biomarkers of synaptic dysfunction, AD-related neurodegeneration, and Aβ cerebral amyloidosis. Magnetic resonance imaging (MRI) and position emission tomography (PET) neuroimaging can be configured as powerful means for the detection of medial-temporal atrophy, reduced uptake of 18F-FDG PET or and increased retention of Aβ amyloid protein by amyloïd-PET. In this review, we will discuss these promising techniques that allow assessing in vivo AD pathology and help clinicians to better diagnose and follow-up patients, particularly in clinical trials using disease-modifying treatments. PMID:27276723

  9. Label-free imaging and quantitative chemical analysis of Alzheimer's disease brain samples with multimodal multiphoton nonlinear optical microspectroscopy

    NASA Astrophysics Data System (ADS)

    Lee, Jang Hyuk; Kim, Dae Hwan; Song, Woo Keun; Oh, Myoung-Kyu; Ko, Do-Kyeong

    2015-05-01

    We developed multimodal multiphoton microspectroscopy using a small-diameter probe with gradient-index lenses and applied it to unstained Alzheimer's disease (AD) brain samples. Our system maintained the image quality and spatial resolution of images obtained using an objective lens of similar numerical aperture. Multicolor images of AD brain samples were obtained simultaneously by integrating two-photon excited fluorescence and second-harmonic generation on a coherent anti-Stokes Raman scattering (CARS) microendoscope platform. Measurements of two hippocampal regions, the cornus ammonis-1 and dentate gyrus, revealed more lipids, amyloid fibers, and collagen in the AD samples than in the normal samples. Normal and AD brains were clearly distinguished by a large spectral difference and quantitative analysis of the CH mode using CARS microendoscope spectroscopy. We expect this system to be an important diagnosis tool in AD research.

  10. Label-free imaging and quantitative chemical analysis of Alzheimer's disease brain samples with multimodal multiphoton nonlinear optical microspectroscopy.

    PubMed

    Lee, Jang Hyuk; Kim, Dae Hwan; Song, Woo Keun; Oh, Myoung-Kyu; Ko, Do-Kyeong

    2015-05-01

    We developed multimodal multiphoton microspectroscopy using a small-diameter probe with gradient-index lenses and applied it to unstained Alzheimer's disease (AD) brain samples. Our system maintained the image quality and spatial resolution of images obtained using an objective lens of similar numerical aperture. Multicolor images of AD brain samples were obtained simultaneously by integrating two-photon excited fluorescence and second-harmonic generation on a coherent anti-Stokes Raman scattering (CARS) microendoscope platform. Measurements of two hippocampal regions, the cornus ammonis-1 and dentate gyrus, revealed more lipids, amyloid fibers, and collagen in the AD samples than in the normal samples. Normal and AD brains were clearly distinguished by a large spectral difference and quantitative analysis of the CH mode using CARS microendoscope spectroscopy. We expect this system to be an important diagnosis tool in AD research

  11. Neuronal uptake and propagation of a rare phosphorylated high-molecular-weight tau derived from Alzheimer's disease brain.

    PubMed

    Takeda, Shuko; Wegmann, Susanne; Cho, Hansang; DeVos, Sarah L; Commins, Caitlin; Roe, Allyson D; Nicholls, Samantha B; Carlson, George A; Pitstick, Rose; Nobuhara, Chloe K; Costantino, Isabel; Frosch, Matthew P; Müller, Daniel J; Irimia, Daniel; Hyman, Bradley T

    2015-10-13

    Tau pathology is known to spread in a hierarchical pattern in Alzheimer's disease (AD) brain during disease progression, likely by trans-synaptic tau transfer between neurons. However, the tau species involved in inter-neuron propagation remains unclear. To identify tau species responsible for propagation, we examined uptake and propagation properties of different tau species derived from postmortem cortical extracts and brain interstitial fluid of tau-transgenic mice, as well as human AD cortices. Here we show that PBS-soluble phosphorylated high-molecular-weight (HMW) tau, though very low in abundance, is taken up, axonally transported, and passed on to synaptically connected neurons. Our findings suggest that a rare species of soluble phosphorylated HMW tau is the endogenous form of tau involved in propagation and could be a target for therapeutic intervention and biomarker development.

  12. Neuronal uptake and propagation of a rare phosphorylated high-molecular-weight tau derived from Alzheimer's disease brain

    PubMed Central

    Takeda, Shuko; Wegmann, Susanne; Cho, Hansang; DeVos, Sarah L.; Commins, Caitlin; Roe, Allyson D.; Nicholls, Samantha B.; Carlson, George A.; Pitstick, Rose; Nobuhara, Chloe K.; Costantino, Isabel; Frosch, Matthew P.; Müller, Daniel J.; Irimia, Daniel; Hyman, Bradley T.

    2015-01-01

    Tau pathology is known to spread in a hierarchical pattern in Alzheimer's disease (AD) brain during disease progression, likely by trans-synaptic tau transfer between neurons. However, the tau species involved in inter-neuron propagation remains unclear. To identify tau species responsible for propagation, we examined uptake and propagation properties of different tau species derived from postmortem cortical extracts and brain interstitial fluid of tau-transgenic mice, as well as human AD cortices. Here we show that PBS-soluble phosphorylated high-molecular-weight (HMW) tau, though very low in abundance, is taken up, axonally transported, and passed on to synaptically connected neurons. Our findings suggest that a rare species of soluble phosphorylated HMW tau is the endogenous form of tau involved in propagation and could be a target for therapeutic intervention and biomarker development. PMID:26458742

  13. Alzheimer's disease in one monozygotic twin

    PubMed Central

    Hunter, Richard; Dayan, A. D.; Wilson, John

    1972-01-01

    A woman of 64 died after an illness lasting 15 years and characterized by a progressive amnesic syndrome followed by global dementia. The brain showed changes typical of Alzheimer's disease. Her monozygotic twin sister was clinically not affected and died two years later of carcinoma. This is the second report of monozygotic twin sisters apparently discordant for presenile dementia of Alzheimer type. PMID:5084139

  14. Dementia: Depression and Alzheimer's Disease

    MedlinePlus

    MENU Return to Web version Dementia | Depression and Alzheimer’s Disease What is depression? When doctors talk about ... time Thoughts about death or suicide What is Alzheimer's disease? Alzheimer's disease is the most common type ...

  15. Progress in Alzheimer's disease.

    PubMed

    Galimberti, Daniela; Scarpini, Elio

    2012-02-01

    After more than one century from Alois Alzheimer and Gaetano Perusini's first report, progress has been made in understanding the pathogenic steps of Alzheimer's disease (AD), as well as in its early diagnosis. This review discusses recent findings leading to the formulation of novel criteria for diagnosis of the disease even in a preclinical phase, by using biological markers. In addition, treatment options will be discussed, with emphasis on new disease-modifying compounds and future trial design suitable to test these drugs in an early phase of the disease.

  16. Treatment of Alzheimer disease.

    PubMed

    Winslow, Bradford T; Onysko, Mary K; Stob, Christian M; Hazlewood, Kathleen A

    2011-06-15

    Alzheimer disease is the most common form of dementia, affecting nearly one-half [corrected] of Americans older than 85 years. It is characterized by progressive memory loss and cognitive decline. Amyloid plaque accumulation, neurofibrillary tau tangles, and depletion of acetylcholine are among the pathologic manifestations of Alzheimer disease. Although there are no proven modalities for preventing Alzheimer disease, hypertension treatment, omega-3 fatty acid supplementation, physical activity, and cognitive engagement demonstrate modest potential. Acetylcholinesterase inhibitors are first-line medications for the treatment of Alzheimer disease, and are associated with mild improvements in cognitive function, behavior, and activities of daily living; however, the clinical relevance of these effects is unclear. The most common adverse effects of acetylcholinesterase inhibitors are nausea, vomiting, diarrhea, dizziness, confusion, and cardiac arrhythmias. Short-term use of the N-methyl-D-aspartate receptor antagonist memantine can modestly improve measures of cognition, behavior, and activities of daily living in patients with moderate to severe Alzheimer disease. Memantine can also be used in combination with acetylcholinesterase inhibitors. Memantine is generally well tolerated, but whether its benefits produce clinically meaningful improvement is controversial. Although N-methyl-D-aspartate receptor antagonists and acetylcholinesterase inhibitors can slow the progression of Alzheimer disease, no pharmacologic agents can reverse the progression. Atypical antipsychotics can improve some behavioral symptoms, but have been associated with increased mortality rates in older patients with dementia. There is conflicting evidence about the benefit of selegiline, testosterone, and ginkgo for the treatment of Alzheimer disease. There is no evidence supporting the beneficial effects of vitamin E, estrogen, or nonsteroidal anti-inflammatory drug therapy.

  17. Bilateral deep brain stimulation of the fornix for Alzheimer's disease: surgical safety in the ADvance trial.

    PubMed

    Ponce, Francisco A; Asaad, Wael F; Foote, Kelly D; Anderson, William S; Rees Cosgrove, G; Baltuch, Gordon H; Beasley, Kara; Reymers, Donald E; Oh, Esther S; Targum, Steven D; Smith, Gwenn S; Lyketsos, Constantine G; Lozano, Andres M

    2016-07-01

    OBJECT This report describes the stereotactic technique, hospitalization, and 90-day perioperative safety of bilateral deep brain stimulation (DBS) of the fornix in patients who underwent DBS for the treatment of mild, probable Alzheimer's disease (AD). METHODS The ADvance Trial is a multicenter, 12-month, double-blind, randomized, controlled feasibility study being conducted to evaluate the safety, efficacy, and tolerability of DBS of the fornix in patients with mild, probable AD. Intraoperative and perioperative data were collected prospectively. All patients underwent postoperative MRI. Stereotactic analyses were performed in a blinded fashion by a single surgeon. Adverse events (AEs) were reported to an independent clinical events committee and adjudicated to determine the relationship between the AE and the study procedure. RESULTS Between June 6, 2012, and April 28, 2014, a total of 42 patients with mild, probable AD were treated with bilateral fornix DBS (mean age 68.2 ± 7.8 years; range 48.0-79.7 years; 23 men and 19 women). The mean planned target coordinates were x = 5.2 ± 1.0 mm (range 3.0-7.9 mm), y = 9.6 ± 0.9 mm (range 8.0-11.6 mm), z = -7.5 ± 1.2 mm (range -5.4 to -10.0 mm), and the mean postoperative stereotactic radial error on MRI was 1.5 ± 1.0 mm (range 0.2-4.0 mm). The mean length of hospitalization was 1.4 ± 0.8 days. Twenty-six (61.9%) patients experienced 64 AEs related to the study procedure, of which 7 were serious AEs experienced by 5 patients (11.9%). Four (9.5%) patients required return to surgery: 2 patients for explantation due to infection, 1 patient for lead repositioning, and 1 patient for chronic subdural hematoma. No patients experienced neurological deficits as a result of the study, and no deaths were reported. CONCLUSIONS Accurate targeting of DBS to the fornix without direct injury to it is feasible across surgeons and treatment centers. At 90 days after surgery, bilateral fornix DBS was well tolerated by patients with

  18. Bilateral deep brain stimulation of the fornix for Alzheimer's disease: surgical safety in the ADvance trial.

    PubMed

    Ponce, Francisco A; Asaad, Wael F; Foote, Kelly D; Anderson, William S; Rees Cosgrove, G; Baltuch, Gordon H; Beasley, Kara; Reymers, Donald E; Oh, Esther S; Targum, Steven D; Smith, Gwenn S; Lyketsos, Constantine G; Lozano, Andres M

    2016-07-01

    OBJECT This report describes the stereotactic technique, hospitalization, and 90-day perioperative safety of bilateral deep brain stimulation (DBS) of the fornix in patients who underwent DBS for the treatment of mild, probable Alzheimer's disease (AD). METHODS The ADvance Trial is a multicenter, 12-month, double-blind, randomized, controlled feasibility study being conducted to evaluate the safety, efficacy, and tolerability of DBS of the fornix in patients with mild, probable AD. Intraoperative and perioperative data were collected prospectively. All patients underwent postoperative MRI. Stereotactic analyses were performed in a blinded fashion by a single surgeon. Adverse events (AEs) were reported to an independent clinical events committee and adjudicated to determine the relationship between the AE and the study procedure. RESULTS Between June 6, 2012, and April 28, 2014, a total of 42 patients with mild, probable AD were treated with bilateral fornix DBS (mean age 68.2 ± 7.8 years; range 48.0-79.7 years; 23 men and 19 women). The mean planned target coordinates were x = 5.2 ± 1.0 mm (range 3.0-7.9 mm), y = 9.6 ± 0.9 mm (range 8.0-11.6 mm), z = -7.5 ± 1.2 mm (range -5.4 to -10.0 mm), and the mean postoperative stereotactic radial error on MRI was 1.5 ± 1.0 mm (range 0.2-4.0 mm). The mean length of hospitalization was 1.4 ± 0.8 days. Twenty-six (61.9%) patients experienced 64 AEs related to the study procedure, of which 7 were serious AEs experienced by 5 patients (11.9%). Four (9.5%) patients required return to surgery: 2 patients for explantation due to infection, 1 patient for lead repositioning, and 1 patient for chronic subdural hematoma. No patients experienced neurological deficits as a result of the study, and no deaths were reported. CONCLUSIONS Accurate targeting of DBS to the fornix without direct injury to it is feasible across surgeons and treatment centers. At 90 days after surgery, bilateral fornix DBS was well tolerated by patients with

  19. Brain-targeted co-delivery of therapeutic gene and peptide by multifunctional nanoparticles in Alzheimer's disease mice.

    PubMed

    Liu, Yang; An, Sai; Li, Jianfeng; Kuang, Yuyang; He, Xi; Guo, Yubo; Ma, Haojun; Zhang, Yu; Ji, Bin; Jiang, Chen

    2016-02-01

    Multifunctional nanocarriers are increasingly promising for disease treatment aimed to regulate multiple pathological dysfunctions and overcome barriers in drug delivery. Here we develop a multifunctional nanocarrier for Alzheimer's disease (AD) treatment by achieving therapeutic gene and peptide co-delivery to brain based on PEGylated dendrigraft poly-l-lysines (DGLs) via systemic administration. The dendritic amine-rich structure of DGLs provides plenty reaction sites and positive charge for drug loading. Successful co-delivery of drugs overcoming the blood-brain barrier by brain-targeted ligand modification was demonstrated both in vitro and in vivo. The pharmacodynamics study of the system following multiple-dosing treatment was verified in transgenic AD mice. Down-regulation of the key enzyme in amyloid-β formation was achieved by delivering non-coding RNA plasmid. Simultaneous delivery of the therapeutic peptide into brain leads to reduction of neurofibrillary tangles. Meanwhile, memory loss rescue in AD mice was also observed. Taken together, the multifunctional nanocarrier provides an excellent drug co-delivery platform for brain diseases.

  20. Influence of drug transporters and stereoselectivity on the brain penetration of pioglitazone as a potential medicine against Alzheimer's disease.

    PubMed

    Chang, Kai Lun; Pee, Hai Ning; Yang, Shili; Ho, Paul C

    2015-03-11

    Pioglitazone is currently undergoing clinical trials for treatment of Alzheimer's disease (AD). However, poor brain penetration remains an obstacle to development of the drug for such intended clinical uses. In this study, we demonstrate that the inhibition of P-glycoprotein (P-gp) significantly increases brain penetration of pioglitazone, whereas inhibition of breast cancer resistance protein (BCRP) has little effect. We also investigate the stereoselectivity of pioglitazone uptake in the brain. When mice were dosed with racemic pioglitazone, the concentration of (+)-pioglitazone was 46.6% higher than that of (-)-pioglitazone in brain tissue and 67.7% lower than that of (-)-pioglitazone in plasma. Dosing mice with pure (+)-pioglitazone led to a 76% increase in brain exposure levels compared to those from an equivalent dose of racemic pioglitazone. Pure (+)-pioglitazone was also shown to have comparable amyloid-lowering capabilities to the racemic pioglitazone in an in vitro AD model. These results suggest that P-gp may act as a stereoselective barrier to prevent pioglitazone entry into the brain. Dosing with (+)-pioglitazone instead of the racemic mixture may result in higher levels of brain exposure to pioglitazone, thus potentially improving the development of pioglitazone treatment of AD.

  1. Alzheimer's disease: neuritic plaques and neurofibrillary tangles in human brain identified by FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Choo, Lin-P'ing; Jackson, Michael; Halliday, William C.; Mantsch, Henry H.

    1994-01-01

    The abnormal abundance of (beta) -amyloid plaques and neurofibrillary tangles are the hallmark of Alzheimer's disease (AD). Human central nervous system (CNS) grey matter was probed for characteristics arising from these pathological features. In AD but not normal grey matter, an IR band at 1615 cm-1 is seen, characteristic of a protein in an aggregated state. We speculate that this band arises from (beta) A4-amyloid protein. AD, and 18q- grey matter spectra show increased intensity of phosphate bands in accordance with known hyperphosphorylation of proteins found in neurofibrillary tangles. These spectral features may be useful in the diagnosis of AD.

  2. Deep Brain Stimulation Tested for Early Alzheimer's

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_160137.html Deep Brain Stimulation Tested for Early Alzheimer's Although treatment seems ... 2016 THURSDAY, July 28, 2016 (HealthDay News) -- Deep brain stimulation appears safe for people with early Alzheimer's ...

  3. p75NTR ectodomain is a physiological neuroprotective molecule against amyloid-beta toxicity in the brain of Alzheimer's disease

    PubMed Central

    Yao, X-Q; Jiao, S-S; Saadipour, K; Zeng, F; Wang, Q-H; Zhu, C; Shen, L-L; Zeng, G-H; Liang, C-R; Wang, J; Liu, Y-H; Hou, H-Y; Xu, X; Su, Y-P; Fan, X-T; Xiao, H-L; Lue, L-F; Zeng, Y-Q; Giunta, B; Zhong, J-H; Walker, D G; Zhou, H-D; Tan, J; Zhou, X-F; Wang, Y-J

    2015-01-01

    In Alzheimer's disease (AD), neurodegenerative signals such as amyloid-beta (Aβ) and the precursors of neurotrophins, outbalance neurotrophic signals, causing synaptic dysfunction and neurodegeneration. The neurotrophin receptor p75 (p75NTR) is a receptor of Aβ and mediates Aβ-induced neurodegenerative signals. The shedding of its ectodomain from the cell surface is physiologically regulated; however, the function of the diffusible p75NTR ectodomain (p75ECD) after shedding remains largely not known. Here, we show that p75ECD levels in cerebrospinal fluid and in the brains of Alzheimer's patients and amyloid-beta precursor protein (APP)/PS1 transgenic mice were significantly reduced, due to inhibition of the sheddase-tumor necrosis factor-alpha-converting enzyme by Aβ. Restoration of p75ECD to the normal level by brain delivery of the gene encoding human p75ECD before or after Aβ deposition in the brain of APP/PS1 mice reversed the behavioral deficits and AD-type pathologies, such as Aβ deposit, apoptotic events, neuroinflammation, Tau phosphorylation and loss of dendritic spine, neuronal structures and synaptic proteins. Furthermore, p75ECD can also reduce amyloidogenesis by suppressing β-secretase expression and activities. Our data demonstrate that p75ECD is a physiologically neuroprotective molecule against Aβ toxicity and would be a novel therapeutic target and biomarker for AD. PMID:25917367

  4. p75NTR ectodomain is a physiological neuroprotective molecule against amyloid-beta toxicity in the brain of Alzheimer's disease.

    PubMed

    Yao, X-Q; Jiao, S-S; Saadipour, K; Zeng, F; Wang, Q-H; Zhu, C; Shen, L-L; Zeng, G-H; Liang, C-R; Wang, J; Liu, Y-H; Hou, H-Y; Xu, X; Su, Y-P; Fan, X-T; Xiao, H-L; Lue, L-F; Zeng, Y-Q; Giunta, B; Zhong, J-H; Walker, D G; Zhou, H-D; Tan, J; Zhou, X-F; Wang, Y-J

    2015-11-01

    In Alzheimer's disease (AD), neurodegenerative signals such as amyloid-beta (Aβ) and the precursors of neurotrophins, outbalance neurotrophic signals, causing synaptic dysfunction and neurodegeneration. The neurotrophin receptor p75 (p75NTR) is a receptor of Aβ and mediates Aβ-induced neurodegenerative signals. The shedding of its ectodomain from the cell surface is physiologically regulated; however, the function of the diffusible p75NTR ectodomain (p75ECD) after shedding remains largely not known. Here, we show that p75ECD levels in cerebrospinal fluid and in the brains of Alzheimer's patients and amyloid-beta precursor protein (APP)/PS1 transgenic mice were significantly reduced, due to inhibition of the sheddase-tumor necrosis factor-alpha-converting enzyme by Aβ. Restoration of p75ECD to the normal level by brain delivery of the gene encoding human p75ECD before or after Aβ deposition in the brain of APP/PS1 mice reversed the behavioral deficits and AD-type pathologies, such as Aβ deposit, apoptotic events, neuroinflammation, Tau phosphorylation and loss of dendritic spine, neuronal structures and synaptic proteins. Furthermore, p75ECD can also reduce amyloidogenesis by suppressing β-secretase expression and activities. Our data demonstrate that p75ECD is a physiologically neuroprotective molecule against Aβ toxicity and would be a novel therapeutic target and biomarker for AD.

  5. Brain in situ hybridization maps as a source for reverse-engineering transcriptional regulatory networks: Alzheimer's disease insights.

    PubMed

    Acquaah-Mensah, George K; Taylor, Ronald C

    2016-07-15

    Microarray data have been a valuable resource for identifying transcriptional regulatory relationships among genes. As an example, brain region-specific transcriptional regulatory events have the potential of providing etiological insights into Alzheimer Disease (AD). However, there is often a paucity of suitable brain-region specific expression data obtained via microarrays or other high throughput means. The Allen Brain Atlas in situ hybridization (ISH) data sets (Jones et al., 2009) represent a potentially valuable alternative source of high-throughput brain region-specific gene expression data for such purposes. In this study, Allen Brain Atlas mouse ISH data in the hippocampal fields were extracted, focusing on 508 genes relevant to neurodegeneration. Transcriptional regulatory networks were learned using three high-performing network inference algorithms. Only 17% of regulatory edges from a network reverse-engineered based on brain region-specific ISH data were also found in a network constructed upon gene expression correlations in mouse whole brain microarrays, thus showing the specificity of gene expression within brain sub-regions. Furthermore, the ISH data-based networks were used to identify instructive transcriptional regulatory relationships. Ncor2, Sp3 and Usf2 form a unique three-party regulatory motif, potentially affecting memory formation pathways. Nfe2l1, Egr1 and Usf2 emerge among regulators of genes involved in AD (e.g. Dhcr24, Aplp2, Tia1, Pdrx1, Vdac1, and Syn2). Further, Nfe2l1, Egr1 and Usf2 are sensitive to dietary factors and could be among links between dietary influences and genes in the AD etiology. Thus, this approach of harnessing brain region-specific ISH data represents a rare opportunity for gleaning unique etiological insights for diseases such as AD.

  6. Graded perturbations of metabolism in multiple regions of human brain in Alzheimer's disease: Snapshot of a pervasive metabolic disorder.

    PubMed

    Xu, Jingshu; Begley, Paul; Church, Stephanie J; Patassini, Stefano; Hollywood, Katherine A; Jüllig, Mia; Curtis, Maurice A; Waldvogel, Henry J; Faull, Richard L M; Unwin, Richard D; Cooper, Garth J S

    2016-06-01

    Alzheimer's disease (AD) is an age-related neurodegenerative disorder that displays pathological characteristics including senile plaques and neurofibrillary tangles. Metabolic defects are also present in AD-brain: for example, signs of deficient cerebral glucose uptake may occur decades before onset of cognitive dysfunction and tissue damage. There have been few systematic studies of the metabolite content of AD human brain, possibly due to scarcity of high-quality brain tissue and/or lack of reliable experimental methodologies. Here we sought to: 1) elucidate the molecular basis of metabolic defects in human AD-brain; and 2) identify endogenous metabolites that might guide new approaches for therapeutic intervention, diagnosis or monitoring of AD. Brains were obtained from nine cases with confirmed clinical/neuropathological AD and nine controls matched for age, sex and post-mortem delay. Metabolite levels were measured in post-mortem tissue from seven regions: three that undergo severe neuronal damage (hippocampus, entorhinal cortex and middle-temporal gyrus); three less severely affected (cingulate gyrus, sensory cortex and motor cortex); and one (cerebellum) that is relatively spared. We report a total of 55 metabolites that were altered in at least one AD-brain region, with different regions showing alterations in between 16 and 33 metabolites. Overall, we detected prominent global alterations in metabolites from several pathways involved in glucose clearance/utilization, the urea cycle, and amino-acid metabolism. The finding that potentially toxigenic molecular perturbations are widespread throughout all brain regions including the cerebellum is consistent with a global brain disease process rather than a localized effect of AD on regional brain metabolism. PMID:26957286

  7. Graded perturbations of metabolism in multiple regions of human brain in Alzheimer's disease: Snapshot of a pervasive metabolic disorder

    PubMed Central

    Xu, Jingshu; Begley, Paul; Church, Stephanie J.; Patassini, Stefano; Hollywood, Katherine A.; Jüllig, Mia; Curtis, Maurice A.; Waldvogel, Henry J.; Faull, Richard L.M.; Unwin, Richard D.; Cooper, Garth J.S.

    2016-01-01

    Alzheimer's disease (AD) is an age-related neurodegenerative disorder that displays pathological characteristics including senile plaques and neurofibrillary tangles. Metabolic defects are also present in AD-brain: for example, signs of deficient cerebral glucose uptake may occur decades before onset of cognitive dysfunction and tissue damage. There have been few systematic studies of the metabolite content of AD human brain, possibly due to scarcity of high-quality brain tissue and/or lack of reliable experimental methodologies. Here we sought to: 1) elucidate the molecular basis of metabolic defects in human AD-brain; and 2) identify endogenous metabolites that might guide new approaches for therapeutic intervention, diagnosis or monitoring of AD. Brains were obtained from nine cases with confirmed clinical/neuropathological AD and nine controls matched for age, sex and post-mortem delay. Metabolite levels were measured in post-mortem tissue from seven regions: three that undergo severe neuronal damage (hippocampus, entorhinal cortex and middle-temporal gyrus); three less severely affected (cingulate gyrus, sensory cortex and motor cortex); and one (cerebellum) that is relatively spared. We report a total of 55 metabolites that were altered in at least one AD-brain region, with different regions showing alterations in between 16 and 33 metabolites. Overall, we detected prominent global alterations in metabolites from several pathways involved in glucose clearance/utilization, the urea cycle, and amino-acid metabolism. The finding that potentially toxigenic molecular perturbations are widespread throughout all brain regions including the cerebellum is consistent with a global brain disease process rather than a localized effect of AD on regional brain metabolism. PMID:26957286

  8. Neuronutrition and Alzheimer's Disease

    PubMed Central

    Ramesh, Balenahalli N.; Rao, T.S. Sathyanarayana; Prakasam, Annamalai; Sambamurti, Kumar; Rao, K.S. Jagannatha

    2010-01-01

    Alzheimer's disease (AD) is a complex neurological disorder with several unequivocally identified genetic risk factors. Among the several environmental factors proposed for AD, dietary protective and risk factors have been most compelling. In particular, diets rich in saturated fatty acids and alcohol, and deficient in antioxidants and vitamins appear to promote the onset of the disease, while diets rich in unsaturated fatty acids, vitamins, antioxidants, and wine likely suppress its onset. Evidence suggests that diets rich in polyphenols and some spices suppress the onset of AD by scavenging free radicals and preventing oxidative damage. Metal ions are known to catalyze the production of free radicals and induce mental retardation or dementia. Several studies have also identified metals such as Pb, Fe, Al, Cu and Zn in AD pathogenesis. While specific chelators have been tested for therapy, they have not been very successful probably due to late administration after brain damage has been triggered. Since several dietary polyphenols are known to chelate metals, their routine use may also be protective against the onset of AD. PMID:20308778

  9. [Biomarkers in Alzheimer's disease].

    PubMed

    García-Ribas, G; López-Sendón Moreno, J L; García-Caldentey, J

    2014-04-01

    The new diagnostic criteria for Alzheimer's disease (AD) include brain imaging and cerebrospinal fluid (CSF) biomarkers, with the aim of increasing the certainty of whether a patient has an ongoing AD neuropathologic process or not. Three CSF biomarkers, Aß42, total tau, and phosphorylated tau, reflect the core pathological features of AD. It is already known that these pathological processes of AD starts decades before the first symptoms, so these biomarkers may provide means of early disease detection. At least three stages of AD could be identified: preclinical AD, mild cognitive impairment due to AD, and dementia due to AD. In this review, we aim to summarize the CSF biomarker data available for each of these stages. We also review the actual research on blood-based biomarkers. Recent studies on healthy elderly subjects and on carriers of dominantly inherited AD mutations have also found biomarker changes that allow separate groups in these preclinical stages. These studies may aid for segregate populations in clinical trials and objectively evaluate if there are changes over the pathological processes of AD. Limits to widespread use of CSF biomarkers, apart from the invasive nature of the process itself, is the higher coefficient of variation for the analyses between centres. It requires strict pre-analytical and analytical procedures that may make feasible multi-centre studies and global cut-off points for the different stages of AD.

  10. Trends in brain oxygenation during mental and physical exercise measured using near-infrared spectroscopy (NIRS): potential for early detection of Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Allen, Monica S.; Allen, Jeffery W.; Mikkilineni, Shweta; Liu, Hanli

    2005-04-01

    Motivation: Early diagnosis of Alzheimer's disease (AD) is crucial because symptoms respond best to available treatments in the initial stages of the disease. Recent studies have shown that marked changes in brain oxygenation during mental and physical tasks can be used for noninvasive functional brain imaging to detect Alzheimer"s disease. The goal of our study is to explore the possibility of using near infrared spectroscopy (NIRS) and mapping (NIRM) as a diagnostic tool for AD before the onset of significant morphological changes in the brain. Methods: A 16-channel NIRS brain imager was used to noninvasively measure spatial and temporal changes in cerebral hemodynamics induced during verbal fluency task and physical activity. The experiments involved healthy subjects (n = 10) in the age range of 25+/-5 years. The NIRS signals were taken from the subjects' prefrontal cortex during the activities. Results and Conclusion: Trends of oxygenated and deoxygenated hemoglobin in the prefrontal cortex of the brain were observed. During the mental stimulation, the subjects showed significant increase in oxygenated hemoglobin [HbO2] with a simultaneous decrease in deoxygenated hemoglobin [Hb]. However, physical exercise caused a rise in levels of HbO2 with small variations in Hb. This study basically demonstrates that NIRM taken from the prefrontal cortex of the human brain is sensitive to both mental and physical tasks and holds potential to serve as a diagnostic means for early detection of Alzheimer's disease.

  11. [Overview on Alzheimer's disease].

    PubMed

    Ihara, Yasuo

    2007-11-01

    It is now one hundred years since the first publication on Alzheimer's disease by Alois Alzheimer. Since 1980's deciphering Alzheimer's disease has greatly quickened, and investigators currently think that it becomes possible to treat or prevent Alzheimer's disease that is the major socioeconomical concern in all the developed countries. We owe this current understanding to three major advances, development of Abeta vaccination and gamma-modifiers, and a series of large-scale prospective studies. J-ADNI is being undertaken from this fall, which follows the protocols by US-ADNI. The major goal is establishment of the surrogate marker for AD based on MRI data. In addition, this project would provide more clarification of MCI and dementia themselves and their differentiation. In view of the temporal profile of Alzheimer disease, it is essential to detect at-risk people who carry senile plaques (amyloid) but are cognitively normal. Even in MCI more than 50% of neurons in layer 2 is already lost. For such very early detection of at-risk people biomaker would be helpful. According to sink hypothesis, there is chemical equilibrium of Abeta between in plasma, CSF and senile plaques. Thus what we should do is to find insoluble Abeta-specific fragments or modifications in the peripheral blood.

  12. Biondi ring tangles in the choroid plexus of Alzheimer's disease and normal aging brains: a quantitative study.

    PubMed

    Wen, G Y; Wisniewski, H M; Kascsak, R J

    1999-06-19

    The choroid plexus (CP) performs the vital function of producing up to 90% (450-1000 ml/day) of cerebrospinal fluid (CSF) to nourish and to protect the brain in the CSF suspension. The CP also acts as a selective barrier between blood and CSF to regulate ions and other essential molecules. However, the accumulation of intracellular inclusions called Biondi ring tangles (BRTs) in CP cells of Alzheimer's disease (AD)/aging brains may affect these vital functions of the CP. Statistical analysis of quantitative data on the numbers of CP cells containing BRTs from 54 brains (29 AD and 25 normal control), age range 1-100 years, indicated a significant difference (p<0.00004) between AD and control brains, using analysis of covariance (ANCOVA) with age as covariate. This study compiled the first set of archives to reveal the distribution pattern of BRTs in the CP of AD brains at various ages. Electron microscopy of negatively stained isolated BRTs revealed that these tangles are made of tightly packed bundles of long filaments with diameter around 10 nm that are morphologically distinct from the more loosely packed/shorter bundles of 6-8 nm amyloid fibrils of neuritic plaques (NPs) and from the 24 nm paired helical filaments of neurofibrillary tangles (NFTs) in AD brain. These data suggest that BRTs may represent a significant and measurable biomarker for AD in addition to NPs and NFTs. PMID:10375650

  13. Biondi ring tangles in the choroid plexus of Alzheimer's disease and normal aging brains: a quantitative study.

    PubMed

    Wen, G Y; Wisniewski, H M; Kascsak, R J

    1999-06-19

    The choroid plexus (CP) performs the vital function of producing up to 90% (450-1000 ml/day) of cerebrospinal fluid (CSF) to nourish and to protect the brain in the CSF suspension. The CP also acts as a selective barrier between blood and CSF to regulate ions and other essential molecules. However, the accumulation of intracellular inclusions called Biondi ring tangles (BRTs) in CP cells of Alzheimer's disease (AD)/aging brains may affect these vital functions of the CP. Statistical analysis of quantitative data on the numbers of CP cells containing BRTs from 54 brains (29 AD and 25 normal control), age range 1-100 years, indicated a significant difference (p<0.00004) between AD and control brains, using analysis of covariance (ANCOVA) with age as covariate. This study compiled the first set of archives to reveal the distribution pattern of BRTs in the CP of AD brains at various ages. Electron microscopy of negatively stained isolated BRTs revealed that these tangles are made of tightly packed bundles of long filaments with diameter around 10 nm that are morphologically distinct from the more loosely packed/shorter bundles of 6-8 nm amyloid fibrils of neuritic plaques (NPs) and from the 24 nm paired helical filaments of neurofibrillary tangles (NFTs) in AD brain. These data suggest that BRTs may represent a significant and measurable biomarker for AD in addition to NPs and NFTs.

  14. A protective mutation against Alzheimer disease?

    PubMed

    Proft, Juliane; Weiss, Norbert

    2012-07-01

    To date, nearly 35.6 million people world wide live with dementia, and the situation is going to get worse by 2050 with 115.4 million cases.(1) In the western world, the prevalence for dementia in people over the age of 60 is greater than 5% and two thirds are due to Alzheimer disease,(2) (-) (5) the most common form of dementias.   Alzheimer disease (AD), first described as "presenile dementia" by the German psychiatrist and neuropathologist Alois Alzheimer in 1906,(6) is a devastating disease characterized by progressive cognitive deterioration, as well as impairments in behavior, language, and visuospatial skills.(7) Furthermore, Alzheimer discovered the presence of intraneuronal tangles and extracellular amyloid plaques in the diseased-damaged brain, the hallmarks of Alzheimer disease.

  15. Alzheimer's disease markers from structural MRI and FDG-PET brain images

    NASA Astrophysics Data System (ADS)

    Chincarini, Andrea; Bosco, Paolo; Gemme, Gianluca; Morbelli, Silvia; Arnaldi, Dario; Sensi, Francesco; Solano, Ilaria; Amoroso, Nicola; Tangaro, Sabina; Longo, Renata; Squarcia, Sandro; Nobili, Flavio

    2012-11-01

    Despite the widespread use of neuroimaging tools (morphological and functional) in the routine diagnostic of cerebral diseases, the information available by the end user -the clinician- remains largely limited to qualitative visual analysis. This restriction greatly reduces the diagnostic impact of neuroimaging in routine clinical practice and increases the risk of misdiagnosis. In this context, researches are focussing on the development of sophisticated automatic analyses able to extract clinically relevant information from the captured data. The identification of biological markers at early stages of Alzheimer's disease (AD) contributes to diagnostic accuracy and adds prognostic value. However, in spite of recent developments, results of structural and functional imaging studies on predicting conversion to AD are not uniform. We provide here an overview of analysis methods and approaches, discussing their contribution to clinical assessment.

  16. Association of brain amyloid-β with cerebral perfusion and structure in Alzheimer's disease and mild cognitive impairment.

    PubMed

    Mattsson, Niklas; Tosun, Duygu; Insel, Philip S; Simonson, Alix; Jack, Clifford R; Beckett, Laurel A; Donohue, Michael; Jagust, William; Schuff, Norbert; Weiner, Michael W

    2014-05-01

    Patients with Alzheimer's disease have reduced cerebral blood flow measured by arterial spin labelling magnetic resonance imaging, but it is unclear how this is related to amyloid-β pathology. Using 182 subjects from the Alzheimer's Disease Neuroimaging Initiative we tested associations of amyloid-β with regional cerebral blood flow in healthy controls (n = 51), early (n = 66) and late (n = 41) mild cognitive impairment, and Alzheimer's disease with dementia (n = 24). Based on the theory that Alzheimer's disease starts with amyloid-β accumulation and progresses with symptoms and secondary pathologies in different trajectories, we tested if cerebral blood flow differed between amyloid-β-negative controls and -positive subjects in different diagnostic groups, and if amyloid-β had different associations with cerebral blood flow and grey matter volume. Global amyloid-β load was measured by florbetapir positron emission tomography, and regional blood flow and volume were measured in eight a priori defined regions of interest. Cerebral blood flow was reduced in patients with dementia in most brain regions. Higher amyloid-β load was related to lower cerebral blood flow in several regions, independent of diagnostic group. When comparing amyloid-β-positive subjects with -negative controls, we found reductions of cerebral blood flow in several diagnostic groups, including in precuneus, entorhinal cortex and hippocampus (dementia), inferior parietal cortex (late mild cognitive impairment and dementia), and inferior temporal cortex (early and late mild cognitive impairment and dementia). The associations of amyloid-β with cerebral blood flow and volume differed across the disease spectrum, with high amyloid-β being associated with greater cerebral blood flow reduction in controls and greater volume reduction in late mild cognitive impairment and dementia. In addition to disease stage, amyloid-β pathology affects cerebral blood flow across the span from controls to

  17. Association of brain amyloid-β with cerebral perfusion and structure in Alzheimer's disease and mild cognitive impairment.

    PubMed

    Mattsson, Niklas; Tosun, Duygu; Insel, Philip S; Simonson, Alix; Jack, Clifford R; Beckett, Laurel A; Donohue, Michael; Jagust, William; Schuff, Norbert; Weiner, Michael W

    2014-05-01

    Patients with Alzheimer's disease have reduced cerebral blood flow measured by arterial spin labelling magnetic resonance imaging, but it is unclear how this is related to amyloid-β pathology. Using 182 subjects from the Alzheimer's Disease Neuroimaging Initiative we tested associations of amyloid-β with regional cerebral blood flow in healthy controls (n = 51), early (n = 66) and late (n = 41) mild cognitive impairment, and Alzheimer's disease with dementia (n = 24). Based on the theory that Alzheimer's disease starts with amyloid-β accumulation and progresses with symptoms and secondary pathologies in different trajectories, we tested if cerebral blood flow differed between amyloid-β-negative controls and -positive subjects in different diagnostic groups, and if amyloid-β had different associations with cerebral blood flow and grey matter volume. Global amyloid-β load was measured by florbetapir positron emission tomography, and regional blood flow and volume were measured in eight a priori defined regions of interest. Cerebral blood flow was reduced in patients with dementia in most brain regions. Higher amyloid-β load was related to lower cerebral blood flow in several regions, independent of diagnostic group. When comparing amyloid-β-positive subjects with -negative controls, we found reductions of cerebral blood flow in several diagnostic groups, including in precuneus, entorhinal cortex and hippocampus (dementia), inferior parietal cortex (late mild cognitive impairment and dementia), and inferior temporal cortex (early and late mild cognitive impairment and dementia). The associations of amyloid-β with cerebral blood flow and volume differed across the disease spectrum, with high amyloid-β being associated with greater cerebral blood flow reduction in controls and greater volume reduction in late mild cognitive impairment and dementia. In addition to disease stage, amyloid-β pathology affects cerebral blood flow across the span from controls to

  18. Leptin in Alzheimer's disease.

    PubMed

    Magalhães, C A; Carvalho, M G; Sousa, L P; Caramelli, P; Gomes, K B

    2015-10-23

    Alzheimer's disease (AD) is the most common cause of progressive dementia in the elderly population. AD is histologically characterized by accumulation of amyloid-β protein (Aβ) on extracellular plaques and deposition of hyperphosphorylated tau protein in intracellular neurofibrillary tangles. Several studies have shown that obesity may precede dementia and that lifestyle factors play a critical role in the onset of AD. Furthermore, accumulating evidence indicates that obesity is an independent risk factor for developing AD. In this scenario, the understanding of the role of adipose tissue in brain health is essential to clarify the establishment of demential processes. The objective of this work was to review studies regarding leptin, an anorexigenic peptide hormone synthesized in adipocytes, in the context of dementia. Some authors proposed that leptin evaluation might be a better predictor of dementia than traditional anthropometric measures. Leptin, once established as a biomarker, could enhance the understanding of late-onset AD risk over the life course, as well as the clinical progression of prodromal state to manifested AD. Other studies have proposed that leptin presents neuroprotective activities, which could be explained by inhibiting the amyloidogenic process, reducing the levels of tau protein phosphorylation and improving the cognitive function.

  19. Ultra-structural analysis of the brain in a Drosophila model of Alzheimer's disease using FIB/SEM microscopy.

    PubMed

    Park, Se Jin; Schertel, Andreas; Lee, Kyung Eun; Han, Sung Sik

    2014-02-01

    Alzheimer's disease (AD), one of the most prevalent neurodegenerative brain diseases, has been extensively researched for years. However, its synaptic structure, which is a basis for understanding neurodegenerative disorders, has not yet been understood clearly. Defining the structures of neurons and their synaptic connections is the significant goal of brain research. To study synaptic connectivity, three-dimensional (3D) reconstructions of the nervous system are very helpful. In this study, the 3D structure of brain synapses in the Drosophila melanogaster Swedish amyloid precursor protein (APP) mutant, which is characterized by early onset AD, was analyzed using focused ion beam/scanning electron microscopy (FIB/SEM). This technique is one of the most useful for 3D reconstruction, as the process of obtaining serial images is fully automated and thus avoids the problems inherent in hand-operated ultrathin serial sectioning. The 3D images of normal and AD brains reported in this study reveal characteristic features of AD such as appearance of autophagy, abnormal axon formation and increased mitochondrial size. This 3D analysis reveals structural change as a basis for understanding neurodegenerative disorder.

  20. P3 beta-amyloid peptide has a unique and potentially pathogenic immunohistochemical profile in Alzheimer's disease brain.

    PubMed Central

    Higgins, L. S.; Murphy, G. M.; Forno, L. S.; Catalano, R.; Cordell, B.

    1996-01-01

    The presence of beta-amyloid in brain tissue is characteristic of Alzheimer's disease (AD). A naturally occurring derivative of the beta-amyloid peptide, p3, possesses all of the structural determinants required for fibril assembly and neurotoxicity. p3-specific antibodies were used to examine the distribution of this peptide in brain. p3 reactivity was absent or sparse in aged non-AD brains but was prevalent in selected areas of AD brain in diffuse deposits and in a subset of dystrophic neurites. p3-reactive dystrophic neurites were found both independent in the neuropil and associated with plaques. Little or no reactivity was observed to amyloid cores in classical plaques or to amyloid in the cerebral vasculature. The exclusive appearance of p3 reactivity in AD brain plus the selective localization of p3 reactivity to abnormal structures in the temporal lobe limbic system suggests that p3 may be a contributing factor to AD pathology. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8701997

  1. From Mild Cognitive Impairment to Alzheimer's Disease: A New Perspective in the "Land" of Human Brain Reactivity and Connectivity.

    PubMed

    Rossini, Paolo Maria; Di Iorio, Riccardo; Granata, Giuseppe; Miraglia, Francesca; Vecchio, Fabrizio

    2016-07-14

    In a recent study, analyzing the modulation of γ-band oscillations, Naro and colleagues demonstrated that transcranial alternating current stimulation could drive the gamma rhythms in the human EEG in cognitive healthy elderly subjects but not in mild cognitive impairment (MCI) prodromal to Alzheimer's disease (AD) and in early AD patients. Therefore, this method is proposed to intercept early in the disease course those MCI subjects who are in a pre-symptomatic stage of an already established AD. This prediction index may help the clinician to adopt a better prevention/follow-up strategy. In this direction, the novel advances in EEG analysis for the evaluation of brain reactivity and connectivity-namely via innovative mathematical approach, i.e., graph theory-represent a promising tool for a non-invasive and easy-to-perform neurophysiological marker that could be used for the pre-symptomatic diagnosis of AD and to predict MCI progression to dementia. PMID:27540962

  2. Synchronizing an aging brain: can entraining circadian clocks by food slow Alzheimer's disease?

    PubMed

    Kent, Brianne A

    2014-01-01

    Alzheimer's disease (AD) is a global epidemic. Unfortunately, we are still without effective treatments or a cure for this disease, which is having devastating consequences for patients, their families, and societies around the world. Until effective treatments are developed, promoting overall health may hold potential for delaying the onset or preventing neurodegenerative diseases such as AD. In particular, chronobiological concepts may provide a useful framework for identifying the earliest signs of age-related disease as well as inexpensive and noninvasive methods for promoting health. It is well reported that AD is associated with disrupted circadian functioning to a greater extent than normal aging. However, it is unclear if the central circadian clock (i.e., the suprachiasmatic nucleus) is dysfunctioning, or whether the synchrony between the central and peripheral clocks that control behavior and metabolic processes are becoming uncoupled. Desynchrony of rhythms can negatively affect health, increasing morbidity and mortality in both animal models and humans. If the uncoupling of rhythms is contributing to AD progression or exacerbating symptoms, then it may be possible to draw from the food-entrainment literature to identify mechanisms for re-synchronizing rhythms to improve overall health and reduce the severity of symptoms. The following review will briefly summarize the circadian system, its potential role in AD, and propose using a feeding-related neuropeptide, such as ghrelin, to synchronize uncoupled rhythms. Synchronizing rhythms may be an inexpensive way to promote healthy aging and delay the onset of neurodegenerative disease such as AD. PMID:25225484

  3. Elevation of brain glucose and polyol-pathway intermediates with accompanying brain-copper deficiency in patients with Alzheimer's disease: metabolic basis for dementia.

    PubMed

    Xu, Jingshu; Begley, Paul; Church, Stephanie J; Patassini, Stefano; McHarg, Selina; Kureishy, Nina; Hollywood, Katherine A; Waldvogel, Henry J; Liu, Hong; Zhang, Shaoping; Lin, Wanchang; Herholz, Karl; Turner, Clinton; Synek, Beth J; Curtis, Maurice A; Rivers-Auty, Jack; Lawrence, Catherine B; Kellett, Katherine A B; Hooper, Nigel M; Vardy, Emma R L C; Wu, Donghai; Unwin, Richard D; Faull, Richard L M; Dowsey, Andrew W; Cooper, Garth J S

    2016-06-09

    Impairment of brain-glucose uptake and brain-copper regulation occurs in Alzheimer's disease (AD). Here we sought to further elucidate the processes that cause neurodegeneration in AD by measuring levels of metabolites and metals in brain regions that undergo different degrees of damage. We employed mass spectrometry (MS) to measure metabolites and metals in seven post-mortem brain regions of nine AD patients and nine controls, and plasma-glucose and plasma-copper levels in an ante-mortem case-control study. Glucose, sorbitol and fructose were markedly elevated in all AD brain regions, whereas copper was correspondingly deficient throughout (all P < 0.0001). In the ante-mortem case-control study, by contrast, plasma-glucose and plasma-copper levels did not differ between patients and controls. There were pervasive defects in regulation of glucose and copper in AD brain but no evidence for corresponding systemic abnormalities in plasma. Elevation of brain glucose and deficient brain copper potentially contribute to the pathogenesis of neurodegeneration in AD.

  4. 3D characterization of brain atrophy in Alzheimer's disease and mild cognitive impairment using tensor-based morphometry.

    PubMed

    Hua, Xue; Leow, Alex D; Lee, Suh; Klunder, Andrea D; Toga, Arthur W; Lepore, Natasha; Chou, Yi-Yu; Brun, Caroline; Chiang, Ming-Chang; Barysheva, Marina; Jack, Clifford R; Bernstein, Matt A; Britson, Paula J; Ward, Chadwick P; Whitwell, Jennifer L; Borowski, Bret; Fleisher, Adam S; Fox, Nick C; Boyes, Richard G; Barnes, Josephine; Harvey, Danielle; Kornak, John; Schuff, Norbert; Boreta, Lauren; Alexander, Gene E; Weiner, Michael W; Thompson, Paul M

    2008-05-15

    Tensor-based morphometry (TBM) creates three-dimensional maps of disease-related differences in brain structure, based on nonlinearly registering brain MRI scans to a common image template. Using two different TBM designs (averaging individual differences versus aligning group average templates), we compared the anatomical distribution of brain atrophy in 40 patients with Alzheimer's disease (AD), 40 healthy elderly controls, and 40 individuals with amnestic mild cognitive impairment (aMCI), a condition conferring increased risk for AD. We created an unbiased geometrical average image template for each of the three groups, which were matched for sex and age (mean age: 76.1 years+/-7.7 SD). We warped each individual brain image (N=120) to the control group average template to create Jacobian maps, which show the local expansion or compression factor at each point in the image, reflecting individual volumetric differences. Statistical maps of group differences revealed widespread medial temporal and limbic atrophy in AD, with a lesser, more restricted distribution in MCI. Atrophy and CSF space expansion both correlated strongly with Mini-Mental State Exam (MMSE) scores and Clinical Dementia Rating (CDR). Using cumulative p-value plots, we investigated how detection sensitivity was influenced by the sample size, the choice of search region (whole brain, temporal lobe, hippocampus), the initial linear registration method (9- versus 12-parameter), and the type of TBM design. In the future, TBM may help to (1) identify factors that resist or accelerate the disease process, and (2) measure disease burden in treatment trials.

  5. Alzheimer and his disease: a brief history.

    PubMed

    Cipriani, Gabriele; Dolciotti, Cristina; Picchi, Lucia; Bonuccelli, Ubaldo

    2011-04-01

    More than 100 years ago, Alois Alzheimer first described the clinical and pathological features of an unusual brain disease during the meeting of the Society of Southwest German Psychiatrists in Tübingen: the patient, Auguste Deter, suffered memory loss, disorientation, hallucinations and delusions and died at the age of 55. In 1910, Emil Kraepelin named the condition with the eponym of "Alzheimer's disease" (AD) that is, now, the most common neurodegenerative disease with more than 25 million cases worldwide and a major medical problem nearing catastrophic levels. The present article discusses Alzheimer's work in the context of his life and time.

  6. Novel role of red wine-derived polyphenols in the prevention of Alzheimer's disease dementia and brain pathology: experimental approaches and clinical implications.

    PubMed

    Pasinetti, Giulio Maria

    2012-10-01

    Recent studies suggest that by the middle of this century, as many as 14 million Americans will have Alzheimer's disease, creating an enormous strain on families, the health care system and the federal budget. There are still widespread misconceptions about issues related to the prevention and/or treatment of disease pathogenesis, leaving us unprepared to deal with the disease. To address these challenges, several therapeutic approaches are currently under investigation, mainly in an attempt to delay disease onset and eventually slow down its progression. Recent epidemiological evidence has implicated the protective role of dietary polyphenols from grape products against Alzheimer's disease. Furthermore, experimental evidence supports the hypothesis that certain bioactive grape-derived polyphenols may protect against Alzheimer's disease-type cognitive deterioration, in part by interfering with the generation and assembly of β-amyloid peptides into neurotoxic oligomeric aggregated species. Brain-targeting polyphenols have been shown to significantly reduce the generation of β-amyloid peptides in primary cortico-hippocampal neuron cultures, and preliminary results indicate that they may influence neuronal synaptic plasticity. Recent evidence has also implicated the role of certain grape-derived preparations in beneficially modulating tau neuropathology, including reducing tau aggregation. Studies suggest that dietary polyphenolics may benefit Alzheimer's disease by modulating multiple disease-modifying modalities, both β-amyloid-dependent and independent mechanisms, and provide impetus for the development of polyphenolic compounds for Alzheimer's disease prevention and/or therapy.

  7. [Repressional effects of the glutamate antibodies on expression of Dffb gene in the brain of rats with experimental Alzheimer's disease].

    PubMed

    Kolobov, V V; Davydova, T V; Zakharova, I A; Gorbatov, V Iu; Fomina, V G

    2012-01-01

    The intranasal administration of glutamate antibodies in the dose of 300 microg/kg one hour after damage on the level of mRNA expression of Dffb gene which codes caspase-activated DNase which participates in intranucleosome fragmentation of genome DNA in apoptosis was investigated in experimental Alzheimer's disease induced by injection of neurotoxic fragment of beta-amyloid protein Abeta25-35 in Meynert basal magnocellular nuclei on rats. On the Day 3 after Abeta25-35 injection is observed significant decrease of the level of mRNA expression of Dffb gene in prefrontal cortex in 37%, and in hippocampus in 62% in the experiment group versus the control group. These differences were not found in the hypothalamus when comparing the experimental and control animals. It was suggested that repressive effect of glutamate antibodies on the level of mRNA expression of Dffb gene reflects stabilization of processes taking place in brain cells in experimental Alzheimer's disease, and in its turn the intensiveness of nerve and glial cells apoptotic death is decreased.

  8. CNF1 Increases Brain Energy Level, Counteracts Neuroinflammatory Markers and Rescues Cognitive Deficits in a Murine Model of Alzheimer's Disease

    PubMed Central

    Travaglione, Sara; Fabbri, Alessia; Guidotti, Marco; Ferri, Alberto; Campana, Gabriele; Fiorentini, Carla

    2013-01-01

    Overexpression of pro-inflammatory cytokines and cellular energy failure are associated with neuroinflammatory disorders, such as Alzheimer's disease. Transgenic mice homozygous for human ApoE4 gene, a well known AD and atherosclerosis animal model, show decreased levels of ATP, increased inflammatory cytokines level and accumulation of beta amyloid in the brain. All these findings are considered responsible for triggering cognitive decline. We have demonstrated that a single administration of the bacterial E. coli protein toxin CNF1 to aged apoE4 mice, beside inducing a strong amelioration of both spatial and emotional memory deficits, favored the cell energy restore through an increment of ATP content. This was accompanied by a modulation of cerebral Rho and Rac1 activity. Furthermore, CNF1 decreased the levels of beta amyloid accumulation and interleukin-1β expression in the hippocampus. Altogether, these data suggest that the pharmacological modulation of Rho GTPases by CNF1 can improve memory performances in an animal model of Alzheimer's disease via a control of neuroinflammation and a rescue of systemic energy homeostasis. PMID:23738020

  9. [Alzheimer's disease and depression].

    PubMed

    Gallarda, T

    1999-11-01

    Alzheimer's disease is the most frequent cause of dementia (60% of all dementias) and affects nearly 300,000 people in France. Alzheimer's disease is a disease of the elderly which generally begins after 60 years and whose prevalence increases markedly after age 75 years. The elderly population is increasing in all Western countries. Alzheimer's disease thus constitutes a veritable emergent public health problem. The rapid inflation of the epidemiological and etiopathogenetic data have contributed to enhanced nosographic definition and finer semiological characterization of the disease. Thus, the classic concept of senile dementia has been totally abandoned. In contrast, the concept of depressive pseudodementia as defined by Kiloh (1961) remains present in the "psychiatric culture". The concept refers to rare clinical situations in which the controversial concept of "test therapy" with antidepressants retains, in the author's opinion, some utility. Depressive or psychobehavioral signs and symptoms frequently inaugurate Alzheimer's disease giving rise to first-line psychiatric management. The use of multidimensional evaluation instruments such as the neuropsychiatric inventory (NPI) has enabled demonstration of the signs and symptoms and their quantification through the course of the disease. In the dementia stage, the psychobehavioral symptoms are related to the patient's awareness of the degradation in his intellectual functions and the loss of independence and to specific neuropathological lesions responsible for "frontal deafferentation". Certain clinical forms of depression of late onset are also characterized by symptoms reflecting hypofrontal signs (blunted affect, apathy, defective initiative, etc.) and severe cognitive disorders. Those depressions are associated with risk factors shared with Alzheimer's disease (sex, age, vascular function, APOE 4) and constitute a risk factor for progression to dementia, requiring regular clinical and neuropsychological

  10. Spatial patterns of atrophy, hypometabolism, and amyloid deposition in Alzheimer's disease correspond to dissociable functional brain networks.

    PubMed

    Grothe, Michel J; Teipel, Stefan J

    2016-01-01

    Recent neuroimaging studies of Alzheimer's disease (AD) have emphasized topographical similarities between AD-related brain changes and a prominent cortical association network called the default-mode network (DMN). However, the specificity of distinct imaging abnormalities for the DMN compared to other intrinsic connectivity networks (ICNs) of the limbic and heteromodal association cortex has not yet been examined systematically. We assessed regional amyloid load using AV45-PET, neuronal metabolism using FDG-PET, and gray matter volume using structural MRI in 473 participants from the Alzheimer's Disease Neuroimaging Initiative, including preclinical, predementia, and clinically manifest AD stages. Complementary region-of-interest and voxel-based analyses were used to assess disease stage- and modality-specific changes within seven principle ICNs of the human brain as defined by a standardized functional connectivity atlas. Amyloid deposition in AD dementia showed a preference for the DMN, but high effect sizes were also observed for other neocortical ICNs, most notably the frontoparietal-control network. Atrophic changes were most specific for an anterior limbic network, followed by the DMN, whereas other neocortical networks were relatively spared. Hypometabolism appeared to be a mixture of both amyloid- and atrophy-related profiles. Similar patterns of modality-dependent network specificity were also observed in the predementia and, for amyloid deposition, in the preclinical stage. These quantitative data confirm a high vulnerability of the DMN for multimodal imaging abnormalities in AD. However, rather than being selective for the DMN, imaging abnormalities more generally affect higher order cognitive networks and, importantly, the vulnerability profiles of these networks markedly differ for distinct aspects of AD pathology.

  11. Down Syndrome and Alzheimer's Disease

    MedlinePlus

    ... A A A Share Plus on Google Plus Alzheimer's & Dementia alz.org | IHaveAlz Overview What Is Dementia ... chapter Join our online community Down Syndrome and Alzheimer's Disease As they age, those affected by Down ...

  12. Involvement of oxidative stress-induced abnormalities in ceramide and cholesterol metabolism in brain aging and Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Cutler, Roy G.; Kelly, Jeremiah; Storie, Kristin; Pedersen, Ward A.; Tammara, Anita; Hatanpaa, Kimmo; Troncoso, Juan C.; Mattson, Mark P.

    2004-02-01

    Alzheimer's disease (AD) is an age-related disorder characterized by deposition of amyloid -peptide (A) and degeneration of neurons in brain regions such as the hippocampus, resulting in progressive cognitive dysfunction. The pathogenesis of AD is tightly linked to A deposition and oxidative stress, but it remains unclear as to how these factors result in neuronal dysfunction and death. We report alterations in sphingolipid and cholesterol metabolism during normal brain aging and in the brains of AD patients that result in accumulation of long-chain ceramides and cholesterol. Membrane-associated oxidative stress occurs in association with the lipid alterations, and exposure of hippocampal neurons to A induces membrane oxidative stress and the accumulation of ceramide species and cholesterol. Treatment of neurons with -tocopherol or an inhibitor of sphingomyelin synthesis prevents accumulation of ceramides and cholesterol and protects them against death induced by A. Our findings suggest a sequence of events in the pathogenesis of AD in which A induces membrane-associated oxidative stress, resulting in perturbed ceramide and cholesterol metabolism which, in turn, triggers a neurodegenerative cascade that leads to clinical disease. amyloid | apoptosis | hippocampus | lipid peroxidation | sphingomyelin

  13. The complex actions of statins in brain and their relevance for Alzheimer's disease treatment: an analytical review.

    PubMed

    Mendoza-Oliva, Aydé; Zepeda, Angélica; Arias, Clorinda

    2014-01-01

    In view that several studies have shown a positive correlation between high cholesterol and an increase in the risk for developing Alzheimer's disease (AD) statins have been proposed as alternative drugs for its treatment and/or prevention. However, the potential benefits of statins remain controversial. Although they have lipid-lowering properties, statins also have pleiotropic effects that are unrelated to cholesterol reduction and have a wide range of biological implications whose consequences in brain function have not been fully characterized. In this work we analyze different studies that have reported both, beneficial and toxic effects for statins in the central nervous system (CNS), and we revise the literature that claims their potential for treating AD. First, we present an overview of the cholesterol metabolism and its regulation in the brain in order to provide the framework for understanding the pathological association between altered cholesterol and AD. Then, we describe the cholesterol-lowering and pleiotropic properties of statins that have been reported in vivo and in in vitro models. We conclude that the effects of statins in the brain are broad and complex and that their use for treating several diseases including AD should be carefully analyzed given their multiple and broad effects. PMID:25274112

  14. MRI morphometry in Alzheimer's disease.

    PubMed

    Matsuda, Hiroshi

    2016-09-01

    MRI based evaluation of brain atrophy is regarded as a valid method to stage the disease and to assess progression in Alzheimer's disease (AD). Volumetric software programs have made it possible to quantify gray matter in the human brain in an automated fashion. At present, voxel based morphometry (VBM) is easily applicable to the routine clinical procedure with a short execution time. The importance of the VBM approach is that it is not biased to one particular structure and is able to assess anatomical differences throughout the brain. Stand-alone VBM software running on Windows, Voxel-based Specific Regional analysis system for AD (VSRAD), has been widely used in the clinical diagnosis of AD in Japan. On the other hand, recent application of graph theory to MRI has made it possible to analyze changes in structural connectivity in AD.

  15. Participation in cognitively-stimulating activities is associated with brain structure and cognitive function in preclinical Alzheimer's disease.

    PubMed

    Schultz, Stephanie A; Larson, Jordan; Oh, Jennifer; Koscik, Rebecca; Dowling, Maritza N; Gallagher, Catherine L; Carlsson, Cynthia M; Rowley, Howard A; Bendlin, Barbara B; Asthana, Sanjay; Hermann, Bruce P; Johnson, Sterling C; Sager, Mark; LaRue, Asenath; Okonkwo, Ozioma C

    2015-12-01

    This study tested the hypothesis that frequent participation in cognitively-stimulating activities, specifically those related to playing games and puzzles, is beneficial to brain health and cognition among middle-aged adults at increased risk for Alzheimer's disease (AD). Three hundred twenty-nine cognitively normal, middle-aged adults (age range, 43.2-73.8 years) enrolled in the Wisconsin Registry for Alzheimer's Prevention (WRAP) participated in this study. They reported their current engagement in cognitive activities using a modified version of the Cognitive Activity Scale (CAS), underwent a structural MRI scan, and completed a comprehensive cognitive battery. FreeSurfer was used to derive gray matter (GM) volumes from AD-related regions of interest (ROIs), and composite measures of episodic memory and executive function were obtained from the cognitive tests. Covariate-adjusted least squares analyses were used to examine the association between the Games item on the CAS (CAS-Games) and both GM volumes and cognitive composites. Higher scores on CAS-Games were associated with greater GM volumes in several ROIs including the hippocampus, posterior cingulate, anterior cingulate, and middle frontal gyrus. Similarly, CAS-Games scores were positively associated with scores on the Immediate Memory, Verbal Learning & Memory, and Speed & Flexibility domains. These findings were not modified by known risk factors for AD. In addition, the Total score on the CAS was not as sensitive as CAS-Games to the examined brain and cognitive measures. For some individuals, participation in cognitive activities pertinent to game playing may help prevent AD by preserving brain structures and cognitive functions vulnerable to AD pathophysiology.

  16. Monoclonal antibodies to a 100-kd protein reveal abundant A beta-negative plaques throughout gray matter of Alzheimer's disease brains.

    PubMed Central

    Schmidt, M. L.; Lee, V. M.; Forman, M.; Chiu, T. S.; Trojanowski, J. Q.

    1997-01-01

    Here we describe the initial characterization of a 100-kd protein recognized by four new monoclonal antibodies that reveal abundant and unique plaque-like lesions throughout gray matter of Alzheimer's disease brains. This 100-kd protein and these new plaque-like lesions were identified by four monoclonal antibodies raised to immunogens extracted from Alzheimer's disease neurofibrillary abnormalities. However, these antibodies did not recognize hyperphosphorylated tau in Western blots or neurofibrillary lesions by immunohistochemistry. As all of these antibodies displayed similar properties, one, AMY117, was used to characterize the new plaque-like lesions in detail. These studies demonstrated that AMY117-positive plaques were not visualized by amyloid stains and never co-localized with A beta deposits, although AMY117-positive and A beta-positive lesions frequently occurred in the same cortical and subcortical gray matter regions. Abundant AMY117-positive plaques were found in the brains of all 32 sporadic Alzheimer's disease patients and all 6 elderly Down's syndrome subjects. Although AMY117-positive plaques also were seen in the brains of nondemented patients with numerous A beta deposits. AMY117-positive plaques were rare or absent in the brains of other elderly controls and patients with other neurodegenerative or neuropsychiatric disorders. We conclude that the AMY117-positive plaques described here for the first time are major lesions of the Alzheimer's disease brain. Thus, it will be important to elucidate the role played by the 100-kd protein and the AMY117 plaques in the etiology and pathogenesis of Alzheimer's disease. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9212733

  17. Cellular signaling roles of TGF beta, TNF alpha and beta APP in brain injury responses and Alzheimer's disease.

    PubMed

    Mattson, M P; Barger, S W; Furukawa, K; Bruce, A J; Wyss-Coray, T; Mark, R J; Mucke, L

    1997-02-01

    beta-Amyloid precursor protein (beta APP), transforming growth factor beta (TGF beta), and tumor necrosis factor-alpha (TNF alpha) are remarkably pleiotropic neural cytokines/neurotrophic factors that orchestrate intricate injury-related cellular and molecular interactions. The links between these three factors include: their responses to injury; their interactive effects on astrocytes, microglia and neurons; their ability to induce cytoprotective responses in neurons; and their association with cytopathological alterations in Alzheimer's disease. Astrocytes and microglia each produce and respond to TGF beta and TNF alpha in characteristic ways when the brain is injured. TGF beta, TNF alpha and secreted forms of beta APP (sAPP) can protect neurons against excitotoxic, metabolic and oxidative insults and may thereby serve neuroprotective roles. On the other hand, under certain conditions TNF alpha and the fibrillogenic amyloid beta-peptide (A beta) derivative of beta APP can promote damage of neuronal and glial cells, and may play roles in neurodegenerative disorders. Studies of genetically manipulated mice in which TGF beta, TNF alpha or beta APP ligand or receptor levels are altered suggest important roles for each factor in cellular responses to brain injury and indicate that mediators of neural injury responses also have the potential to enhance amyloidogenesis and/or to interfere with neuroregeneration if expressed at abnormal levels or modified by strategic point mutations. Recent studies have elucidated signal transduction pathways of TGF beta (serine/threonine kinase cascades), TNF alpha (p55 receptor linked to a sphingomyelin-ceramide-NF kappa B pathway), and secreted forms of beta APP (sAPP; receptor guanylate cyclase-cGMP-cGMP-dependent kinase-K+ channel activation). Knowledge of these signaling pathways is revealing novel molecular targets on which to focus neuroprotective therapeutic strategies in disorders ranging from stroke to Alzheimer's disease

  18. Role of the JNK-interacting protein 1/islet brain 1 in cell degeneration in Alzheimer disease and diabetes.

    PubMed

    Beeler, Nicole; Riederer, Beat M; Waeber, Gérard; Abderrahmani, Amar

    2009-10-28

    Numerous epidemiological studies and some pharmacological clinical trials show the close connection between Alzheimer disease (AD) and type 2 diabetes (T2D) and thereby, shed more light into the existence of possible similar pathogenic mechanisms between these two diseases. Diabetes increases the risk of developing AD and sensitizers of insulin currently used as diabetes drugs can efficiently slow cognitive decline of the neurological disorder. Deposits of amyloid aggregate and hyperphosphorylation of tau, which are hallmarks of AD, have been also found in degenerating pancreatic islets beta-cells of patients with T2D. These events may have a causal role in the pathogenesis of the two diseases. Increased c-Jun NH(2)-terminal kinase (JNK) activity is found in neurofibrillary tangles (NFT) of AD and promotes programmed cell death of beta-cells exposed to a diabetic environment. The JNK-interacting protein 1 (JIP-1), also called islet brain 1 (IB1) because it is mostly expressed in the brain and islets, is a key regulator of the JNK pathway in neuronal and beta-cells. JNK, hyperphosphorylated tau and IB1/JIP-1 all co-localize with amyloids deposits in NFT and islets of AD and patients with T2D. This review discusses the role of the IB1/JIP-1 and the JNK pathway in the molecular pathogenesis of AD and T2D.

  19. Multi-resolution Statistical Analysis of Brain Connectivity Graphs in Preclinical Alzheimer's Disease

    PubMed Central

    Kim, Won Hwa; Adluru, Nagesh; Chung, Moo K.; Okonkwo, Ozioma C.; Johnson, Sterling C.; Bendlin, Barbara; Singh, Vikas

    2015-01-01

    There is significant interest, both from basic and applied research perspectives, in understanding how structural/functional connectivity changes can explain behavioral symptoms and predict decline in neurodegenerative diseases such as Alzheimer's disease (AD). The first step in most such analyses is to encode the connectivity information as a graph; then, one may perform statistical inference on various ‘global’ graph theoretic summary measures (e.g., modularity, graph diameter) and/or at the level of individual edges (or connections). For AD in particular, clear differences in connectivity at the dementia stage of the disease (relative to healthy controls) have been identified. Despite such findings, AD-related connectivity changes in preclinical disease remain poorly characterized. Such preclinical datasets are typically smaller and group differences are weaker. In this paper, we propose a new multi-resolution method for performing statistical analysis of connectivity networks/graphs derived from neuroimaging data. At the high level, the method occupies the middle ground between the two contrasts — that is, to analyze global graph summary measures (global) or connectivity strengths or correlations for individual edges similar to voxel based analysis (local). Instead, our strategy derives a Wavelet representation at each primitive (connection edge) which captures the graph context at multiple resolutions. We provide extensive empirical evidence of how this framework offers improved statistical power by analyzing two distinct AD datasets. Here, connectivity is derived from diffusion tensor magnetic resonance images by running a tractography routine. We first present results showing significant connectivity differences between AD patients and controls that were not evident using standard approaches. Later, we show results on populations that are not diagnosed with AD but have a positive family history risk of AD where our algorithm helps in identifying

  20. Putative Role of Red Wine Polyphenols against Brain Pathology in Alzheimer's and Parkinson's Disease.

    PubMed

    Caruana, Mario; Cauchi, Ruben; Vassallo, Neville

    2016-01-01

    Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common age-related neurodegenerative disorders and hence pose remarkable socio-economical burdens to both families and state. Although AD and PD have different clinical and neuropathological features, they share common molecular mechanisms that appear to be triggered by multi-factorial events, such as protein aggregation, mitochondrial dysfunction, oxidative stress (OS), and neuroinflammation, ultimately leading to neuronal cell death. Currently, there are no established and validated disease-modifying strategies for either AD or PD. Among the various lifestyle factors that may prevent or slow age-related neurodegenerative diseases, epidemiological studies on moderate consumption of red wine, especially as part of a holistic Mediterranean diet, have attracted increasing interest. Red wine is particularly rich in specific polyphenolic compounds that appear to affect the biological processes of AD and PD, such as quercetin, myricetin, catechins, tannins, anthocyanidins, resveratrol, and ferulic acid. Indeed, there is now a consistent body of in vitro and in vivo data on the neuroprotective effects of red wine polyphenols (RWP) showing that they do not merely possess antioxidant properties, but may additionally act upon, in a multi-target manner, the underlying key mechanisms featuring in both AD and PD. Furthermore, it is important that bioavailability issues are addressed in order for neuroprotection to be relevant in a clinical study scenario. This review summarizes the current knowledge about the major classes of RWP and places into perspective their potential to be considered as nutraceuticals to target neuropathology in AD and PD. PMID:27570766

  1. Multi-resolution statistical analysis of brain connectivity graphs in preclinical Alzheimer's disease.

    PubMed

    Kim, Won Hwa; Adluru, Nagesh; Chung, Moo K; Okonkwo, Ozioma C; Johnson, Sterling C; B Bendlin, Barbara; Singh, Vikas

    2015-09-01

    There is significant interest, both from basic and applied research perspectives, in understanding how structural/functional connectivity changes can explain behavioral symptoms and predict decline in neurodegenerative diseases such as Alzheimer's disease (AD). The first step in most such analyses is to encode the connectivity information as a graph; then, one may perform statistical inference on various 'global' graph theoretic summary measures (e.g., modularity, graph diameter) and/or at the level of individual edges (or connections). For AD in particular, clear differences in connectivity at the dementia stage of the disease (relative to healthy controls) have been identified. Despite such findings, AD-related connectivity changes in preclinical disease remain poorly characterized. Such preclinical datasets are typically smaller and group differences are weaker. In this paper, we propose a new multi-resolution method for performing statistical analysis of connectivity networks/graphs derived from neuroimaging data. At the high level, the method occupies the middle ground between the two contrasts - that is, to analyze global graph summary measures (global) or connectivity strengths or correlations for individual edges similar to voxel based analysis (local). Instead, our strategy derives a Wavelet representation at each primitive (connection edge) which captures the graph context at multiple resolutions. We provide extensive empirical evidence of how this framework offers improved statistical power by analyzing two distinct AD datasets. Here, connectivity is derived from diffusion tensor magnetic resonance images by running a tractography routine. We first present results showing significant connectivity differences between AD patients and controls that were not evident using standard approaches. Later, we show results on populations that are not diagnosed with AD but have a positive family history risk of AD where our algorithm helps in identifying potentially

  2. A biophysical model of brain deformation to simulate and analyze longitudinal MRIs of patients with Alzheimer's disease.

    PubMed

    Khanal, Bishesh; Lorenzi, Marco; Ayache, Nicholas; Pennec, Xavier

    2016-07-01

    We propose a framework for developing a comprehensive biophysical model that could predict and simulate realistic longitudinal MRIs of patients with Alzheimer's disease (AD). The framework includes three major building blocks: i) atrophy generation, ii) brain deformation, and iii) realistic MRI generation. Within this framework, this paper focuses on a detailed implementation of the brain deformation block with a carefully designed biomechanics-based tissue loss model. For a given baseline brain MRI, the model yields a deformation field imposing the desired atrophy at each voxel of the brain parenchyma while allowing the CSF to expand as required to globally compensate for the locally prescribed volume loss. Our approach is inspired by biomechanical principles and involves a system of equations similar to Stokes equations in fluid mechanics but with the presence of a non-zero mass source term. We use this model to simulate longitudinal MRIs by prescribing complex patterns of atrophy. We present experiments that provide an insight into the role of different biomechanical parameters in the model. The model allows simulating images with exactly the same tissue atrophy but with different underlying deformation fields in the image. We explore the influence of different spatial distributions of atrophy on the image appearance and on the measurements of atrophy reported by various global and local atrophy estimation algorithms. We also present a pipeline that allows evaluating atrophy estimation algorithms by simulating longitudinal MRIs from large number of real subject MRIs with complex subject-specific atrophy patterns. The proposed framework could help understand the implications of different model assumptions, regularization choices, and spatial priors for the detection and measurement of brain atrophy from longitudinal brain MRIs.

  3. Exercise for the diabetic brain: how physical training may help prevent dementia and Alzheimer's disease in T2DM patients.

    PubMed

    Bertram, Sebastian; Brixius, Klara; Brinkmann, Christian

    2016-08-01

    Epidemiological studies indicate that patients with type 2 diabetes mellitus (T2DM) are at increased risk of developing dementia/Alzheimer's disease (AD). This review, which is based on recent studies, presents a molecular framework that links the two diseases and explains how physical training could help counteract neurodegeneration in T2DM patients. Inflammatory, oxidative, and metabolic changes in T2DM patients cause cerebrovascular complications and can lead to blood-brain-barrier (BBB) breakdown. Peripherally increased pro-inflammatory molecules can then pass the BBB more easily and activate stress-activated pathways, thereby promoting key pathological features of dementia/AD such as brain insulin resistance, mitochondrial dysfunction, and accumulation of neurotoxic beta-amyloid (Aβ) oligomers, leading to synaptic loss, neuronal dysfunction, and cell death. Ceramides can also pass the BBB, induce pro-inflammatory reactions, and disturb brain insulin signaling. In a vicious circle, oxidative stress and the pro-inflammatory environment intensify, leading to further cognitive decline. Low testosterone levels might be a common risk factor in T2DM and AD. Regular physical exercise reinforces antioxidative capacity, reduces oxidative stress, and has anti-inflammatory effects. It improves endothelial function and might increase brain capillarization. Physical training can further counteract dyslipidemia and reduce increased ceramide levels. It might also improve Aβ clearance by up-regulating Aβ transporters and, in some cases, increase basal testosterone levels. In addition, regular physical activity can induce neurogenesis. Physical training should therefore be emphasized as a part of prevention programs developed for diabetic patients to minimize the risk of the onset of neurodegenerative diseases among this specific patient group. PMID:27160819

  4. Nerve growth factor in Alzheimer's disease: increased levels throughout the brain coupled with declines in nucleus basalis.

    PubMed

    Scott, S A; Mufson, E J; Weingartner, J A; Skau, K A; Crutcher, K A

    1995-09-01

    The current study analyzed NGF protein levels in the brains of patients with Alzheimer's disease (AD) as compared with aged neurologically normal individuals. An established two-site ELISA was used to measure NGF-like immunoreactivity in the hippocampus, superior temporal gyrus, superior frontal gyrus, inferior parietal lobule, frontal and occipital cortical poles, cerebellum, amygdala, putamen, and nucleus basalis of Meynert (nbM). ChAT activity was assayed in adjacent tissue samples. NGF levels were also evaluated in Parkinson's disease for comparison with both AD and age-matched control cases. Regardless of the brain bank (University of Cincinnati, Rush Presbyterian St. Luke's Medical Center in Chicago, or University of Alabama at Birmingham), NGF-like activity was at least moderately increased with AD in virtually every brain region examined except for the nbM, in which significant declines were observed. NGF levels were also increased when compared with age-matched Parkinson's cases (frontal cortex). NGF-like activity was not related to age at onset or disease duration in AD cases, nor did NGF levels correlate with age at death in the control or AD groups. Correlations between ChAT and NGF-like activity across brains varied considerably and were generally not significant. The present findings indicate that AD is characterized by a widespread increase in cortical and subcortical NGF. Although a correlation with ChAT activity was not observed in cortex, the AD-related decline in NGF found in nbM is consistent with the possibility of impaired retrograde transport of NGF to this region.

  5. Structural brain alterations in heart failure: a review of the literature and implications for risk of Alzheimer's disease.

    PubMed

    Alosco, Michael L; Hayes, Scott M

    2015-09-01

    Cardiovascular disease is a recognized contributor to the pathogenesis of Alzheimer's disease (AD). Heart failure (HF) is a cardiovascular subtype that can be used to model the contribution of cardiovascular disease to AD. Neuroimaging research indicates that HF patients exhibit a diverse range of structural brain alterations and epidemiological studies suggest HF may be an important risk factor for AD. The neural alterations observed in HF may overlap with those observed in AD and contribute to increased risk of AD in HF patients. To examine this possibility, we reviewed structural MRI studies in persons with HF. We examined subcortical brain regions affected in the early stages of AD (medial temporal lobes), as well as cortical alterations that typically occur in the later stages of AD. Our review indicates that patients with HF exhibit greater neural atrophy and white matter microstructural alterations of nearly every region of the Papez circuit (e.g., hippocampus, cingulate gyrus, thalamus, mammillary bodies, and fornix), as well-significant alterations in cortical and cerebellar regions. Based on animal research and past work in AD patients, the mechanisms for structural brain changes in HF may stem from reductions in cerebral blood flow subsequent to cardiac deficiency. This review supports the hypothesis that HF may contribute to AD risk via widespread structural brain changes, including many of the same regions affected by AD. Case-controlled prospective neuroimaging studies with long-term follow-ups are needed to clarify the risk of AD in HF and elucidate the neural underpinnings of AD risk in HF.

  6. Synthesis and amyloid binding properties of rhenium complexes: preliminary progress toward a reagent for SPECT imaging of Alzheimer's disease brain.

    PubMed

    Zhen, W; Han, H; Anguiano, M; Lemere, C A; Cho, C G; Lansbury, P T

    1999-07-29

    The definitive diagnosis of Alzheimer's disease (AD) requires the detection of amyloid plaques in postmortem brain. Although the amount of fibrillar amyloid roughly correlates with the severity of symptoms at the time of death, the temporal relationship between amyloid deposition, neuronal loss, and cognitive decline is unclear. To elucidate this relationship, a noninvasive, practical method for the quantitation of brain amyloid deposition is required. We describe herein the initial stages of a strategy to accomplish this goal by single photon computed tomographic imaging. The amyloid-binding dye Congo Red was modified to allow its conjugation to the monoamine-monoamide bis(thiol) ligand. This ligand complexes technetium(V) in its neutral oxo form. A biphenyl-containing building block was conjugated to the protected ligand, and the product was coupled to the relevant aromatic compounds. Rhenium oxo complexes, which are isosteric, but nonradioactive, analogues of the potential imaging agent technetium oxo complexes, were synthesized. These complexes bound to Abeta amyloid fibrils produced in vitro and stained amyloid plaques and vascular amyloid in AD brain sections. PMID:10425090

  7. An Ensemble-of-Classifiers Based Approach for Early Diagnosis of Alzheimer's Disease: Classification Using Structural Features of Brain Images

    PubMed Central

    Farhan, Saima; Tauseef, Huma

    2014-01-01

    Structural brain imaging is playing a vital role in identification of changes that occur in brain associated with Alzheimer's disease. This paper proposes an automated image processing based approach for the identification of AD from MRI of the brain. The proposed approach is novel in a sense that it has higher specificity/accuracy values despite the use of smaller feature set as compared to existing approaches. Moreover, the proposed approach is capable of identifying AD patients in early stages. The dataset selected consists of 85 age and gender matched individuals from OASIS database. The features selected are volume of GM, WM, and CSF and size of hippocampus. Three different classification models (SVM, MLP, and J48) are used for identification of patients and controls. In addition, an ensemble of classifiers, based on majority voting, is adopted to overcome the error caused by an independent base classifier. Ten-fold cross validation strategy is applied for the evaluation of our scheme. Moreover, to evaluate the performance of proposed approach, individual features and combination of features are fed to individual classifiers and ensemble based classifier. Using size of left hippocampus as feature, the accuracy achieved with ensemble of classifiers is 93.75%, with 100% specificity and 87.5% sensitivity. PMID:25276224

  8. Methylene Blue Improves Brain Mitochondrial ABAD Functions and Decreases Aβ in a Neuroinflammatory Alzheimer's Disease Mouse Model.

    PubMed

    Zakaria, Aya; Hamdi, Nabila; Abdel-Kader, Reham Mahmoud

    2016-03-01

    Methylene blue (MB) phase II clinical trials reported improvements in cognitive functions of Alzheimer's disease (AD) patients. Regarding MB mechanism of action, its antioxidant and mitochondrial protective effects have been previously described. In relation to AD, it has been recently reported that MB reduced amyloid beta (Aβ) levels in AD models. The mitochondrial enzyme amyloid-binding alcohol dehydrogenase (ABAD) has been shown to bind Aβ inducing mitochondrial dysfunction, providing a direct relation between Aβ toxicity and mitochondrial dysfunction occurring in AD. Since it has been reported that inhibiting ABAD protects mitochondrial functions and prevents Aβ-induced toxicity, the aim of the current study was to investigate if the protective effects of MB could be associated with an effect on ABAD levels and functions. The current study shows that MB is able to enhance cell viability, reduce both reactive oxygen species levels and importantly Aβ oligomers in a lipopolysaccharide (LPS) mouse model. Interestingly, ABAD levels were increased in the brains of the LPS mouse model and MB treatment was able to reduce its levels. Given that regulation of the estradiol level is a well-established function of ABAD, brain estradiol level was compared in LPS mouse model and in MB-treated mice. The results of the current study show that MB treatment is able to improve significantly the LPS-induced decrease of estradiol levels in mice brains, indicating its ability to modulate both levels and function of ABAD. These results give a new insight to possible mechanisms of MB in AD.

  9. Role of Methylglyoxal in Alzheimer's Disease

    PubMed Central

    Zambonin, Laura; Hrelia, Silvana

    2014-01-01

    Alzheimer's disease is the most common and lethal neurodegenerative disorder. The major hallmarks of Alzheimer's disease are extracellular aggregation of amyloid β peptides and, the presence of intracellular neurofibrillary tangles formed by precipitation/aggregation of hyperphosphorylated tau protein. The etiology of Alzheimer's disease is multifactorial and a full understanding of its pathogenesis remains elusive. Some years ago, it has been suggested that glycation may contribute to both extensive protein cross-linking and oxidative stress in Alzheimer's disease. Glycation is an endogenous process that leads to the production of a class of compounds known as advanced glycation end products (AGEs). Interestingly, increased levels of AGEs have been observed in brains of Alzheimer's disease patients. Methylglyoxal, a reactive intermediate of cellular metabolism, is the most potent precursor of AGEs and is strictly correlated with an increase of oxidative stress in Alzheimer's disease. Many studies are showing that methylglyoxal and methylglyoxal-derived AGEs play a key role in the etiopathogenesis of Alzheimer's disease. PMID:24734229

  10. Patients that have Undergone Hemodialysis Exhibit Lower Amyloid Deposition in the Brain: Evidence Supporting a Therapeutic Strategy for Alzheimer's Disease by Removal of Blood Amyloid.

    PubMed

    Sakai, Kazuyoshi; Senda, Takao; Hata, Ryuji; Kuroda, Makoto; Hasegawa, Midori; Kato, Masao; Abe, Masato; Kawaguchi, Kazunori; Nakai, Shigeru; Hiki, Yoshiyuki; Yuzawa, Yukio; Kitaguchi, Nobuya

    2016-01-01

    As a proof of concept that removal of blood amyloid-β (Aβ) can reduce Aβ deposition in the brains of patients with Alzheimer's disease, cortices of patients who had undergone hemodialysis (HD), which removes Aβ from the blood, were histochemically analyzed; postmortem brain sections were stained with anti-Aβ antibodies. Brains from patients who had undergone HD had significantly fewer senile plaques than those of patient who had not undergone HD. This significant difference was also confirmed by silver staining. Our findings suggest that removal of blood Aβ by hemodialysis results in lower accumulation of Aβ in the brain.

  11. Caspase-cleaved glial fibrillary acidic protein within cerebellar white matter of the Alzheimer's disease brain.

    PubMed

    Rohn, Troy T; Catlin, Lindsey W; Poon, Wayne W

    2013-01-01

    Although the cerebellum is generally thought of as an area spared of Alzheimer's disease (AD) pathology, recent evidence suggests that balance and mobility dysfunction may be magnified in affected individuals. In the present study, we sought to determine the degree of pathological changes within the cerebellum utilizing an antibody that specifically detects caspase-cleaved GFAP within degenerating astrocytes. Compared to control subjects, application of this antibody, termed the GFAP caspase-cleavage product (GFAPccp) antibody, revealed widespread labeling in cerebellar white matter with little staining observed in grey matter. Staining was observed within damaged astrocytes, was often localized near blood vessels and co-localized with other markers of apoptosis including TUNEL and caspase-cleaved tau. Of interest was the association of beta-amyloid deposition in white matter together with GFAPccp in cerebellar AD sections. In contrast, utilizing the tangle marker, PHF-1, neuritic pathology was completely absent in AD cerebellar sections. It is suggested that the observed pathological changes found in the white matter of the cerebellum may contribute to the declined motor performance in AD.

  12. Transthyretin and the brain re-visited: Is neuronal synthesis of transthyretin protective in Alzheimer's disease?

    PubMed Central

    2011-01-01

    Since the mid-1990's a trickle of publications from scattered independent laboratories have presented data suggesting that the systemic amyloid precursor transthyretin (TTR) could interact with the amyloidogenic β-amyloid (Aβ) peptide of Alzheimer's disease (AD). The notion that one amyloid precursor could actually inhibit amyloid fibril formation by another seemed quite far-fetched. Further it seemed clear that within the CNS, TTR was only produced in choroid plexus epithelial cells, not in neurons. The most enthusiastic of the authors proclaimed that TTR sequestered Aβ in vivo resulting in a lowered TTR level in the cerebrospinal fluid (CSF) of AD patients and that the relationship was salutary. More circumspect investigators merely showed in vitro interaction between the two molecules. A single in vivo study in Caenorhabditis elegans suggested that wild type human TTR could suppress the abnormalities seen when Aβ was expressed in the muscle cells of the worm. Subsequent studies in human Aβ transgenic mice, including those from our laboratory, also suggested that the interaction reduced the Aβ deposition phenotype. We have reviewed the literature analyzing the relationship including recent data examining potential mechanisms that could explain the effect. We have proposed a model which is consistent with most of the published data and current notions of AD pathogenesis and can serve as a hypothesis which can be tested. PMID:22112803

  13. In Situ FTIR Microspectroscopy of Brain Tissue from a Transgenic Mouse Model of Alzheimer Disease

    SciTech Connect

    Rak,M.; Del Bigio, M.; Mai, S.; Westaway, D.; Gough, K.

    2007-01-01

    Plaques composed of the A{beta} peptide are the main pathological feature of Alzheimer's disease. Dense-core plaques are fibrillar deposits of A{beta}, showing all the classical properties of amyloid including {beta}-sheet secondary structure, while diffuse plaques are amorphous deposits. We studied both plaque types, using synchrotron infrared (IR) microspectroscopy, a technique that allows the chemical composition and average protein secondary structure to be investigated in situ. We examined plaques in hippocampal, cortical and caudal tissue from 5- to 21-month-old TgCRND8 mice, a transgenic model expressing doubly mutant amyloid precursor protein, and displaying impaired hippocampal function and robust pathology from an early age. Spectral analysis confirmed that the congophilic plaque cores were composed of protein in a {beta}-sheet conformation. The amide I maximum of plaque cores was at 1623 cm-1, and unlike for in vitro A{beta} fibrils, the high-frequency (1680-1690 cm-1) component attributed to antiparallel {beta}-sheet was not observed. A significant elevation in phospholipids was found around dense-core plaques in TgCRND8 mice ranging in age from 5 to 21 months. In contrast, diffuse plaques were not associated with IR detectable changes in protein secondary structure or relative concentrations of any other tissue components.

  14. Lipid peroxidation triggers neurodegeneration: a redox proteomics view into the Alzheimer disease brain.

    PubMed

    Sultana, Rukhsana; Perluigi, Marzia; Allan Butterfield, D

    2013-09-01

    Lipid peroxidation involves a cascade of reactions in which production of free radicals occurs selectively in the lipid components of cellular membranes. Polyunsaturated fatty acids easily undergo lipid peroxidation chain reactions, which, in turn, lead to the formation of highly reactive electrophilic aldehydes. Among these, the most abundant aldehydes are 4-hydroxy-2-nonenal (HNE) and malondialdehyde, while acrolein is the most reactive. Proteins are susceptible to posttranslational modifications caused by aldehydes binding covalently to specific amino acid residues, in a process called Michael adduction, and these types of protein adducts, if not efficiently removed, may be, and generally are, dangerous for cellular homeostasis. In the present review, we focused the discussion on the selective proteins that are identified, by redox proteomics, as selective targets of HNE modification during the progression and pathogenesis of Alzheimer disease (AD). By comparing results obtained at different stages of the AD, it may be possible to identify key biochemical pathways involved and ideally identify therapeutic targets to prevent, delay, or treat AD.

  15. Lipid Peroxidation Triggers Neurodegeneration: A Redox Proteomics View into the Alzheimer Disease Brain

    PubMed Central

    Sultana, Rukhsana; Perluigi, Marzia; Butterfield, D. Allan

    2012-01-01

    Lipid peroxidation involves a cascade of reactions in which production of free radicals occurs selectively in the lipid components of cellular membranes. Polyunsaturated fatty acids easily undergo lipid peroxidation chain reactions, which, in turn, lead to the formation of highly reactive electrophilic aldehydes. Among these, the most abundant aldehydes are 4-hydroxy-2-nonenal (HNE) and malondialdehyde, while acrolein is the most reactive. Proteins are susceptible to post-translational modifications caused by aldehydes binding covalently to specific amino acid residues, in a process called Michael adduction, and these types of protein adducts, if not efficiently removed, may be, and generally are, dangerous for cellular homeostasis. In the present review, we focused the discussion on the selective proteins that are identified, by redox proteomics, as selective targets of HNE-modification during the progression and pathogenesis of Alzheimer disease (AD). By comparing results obtained at different stages of the AD, it may be possible to identify key biochemical pathways involved and ideally identify therapeutic targets to prevent, delay or treat AD. PMID:23044265

  16. Whole-brain patterns of (1)H-magnetic resonance spectroscopy imaging in Alzheimer's disease and dementia with Lewy bodies.

    PubMed

    Su, L; Blamire, A M; Watson, R; He, J; Hayes, L; O'Brien, J T

    2016-01-01

    Magnetic resonance spectroscopy has demonstrated metabolite changes in neurodegenerative disorders such as Alzheimer's disease (AD) and dementia with Lewy bodies (DLB); however, their pattern and relationship to clinical symptoms is unclear. To determine whether the spatial patterns of brain-metabolite changes in AD and DLB are regional or diffused, and to examine whether the key metabolite levels are associated with cognitive and non-cognitive symptoms, we acquired whole-brain spatially resolved 3T magnetic resonance spectroscopic imaging (MRSI) data from subjects with AD (N=36), DLB (N=35) and similarly aged controls (N=35). Voxel-wise measurement of N-acetylaspartate to creatine (NAA/Cr), choline to Cr (Cho/Cr), myo-inositol to Cr (mI/Cr) as well as glutamate and glutamine to Cr (Glx/Cr) ratios were determined using MRSI. Compared with controls, AD and DLB groups showed a significant decrease in most brain metabolites, with NAA/Cr, Cho/Cr and mI/Cr levels being reduced in posterior cingulate, thalamus, frontotemporal areas and basal ganglia. The Glx/Cr level was more widely decreased in DLB (posterior cingulate, hippocampus, temporal regions and caudate) than in AD (only in posterior cingulate). DLB was also associated with increased levels of Cho/Cr, NAA/Cr and mI/Cr in occipital regions. Changes in metabolism in the brain were correlated with cognitive and non-cognitive symptoms in the DLB but not in the AD group. The different patterns between AD and DLB may have implications for improving diagnosis, better understanding disease-specific neurobiology and targeting therapeutics. In addition, the study raised important questions about the role of occipital neuroinflammation and glial activation as well as the glutamatergic treatment in DLB. PMID:27576166

  17. A novel LDL-mimic nanocarrier for the targeted delivery of curcumin into the brain to treat Alzheimer's disease.

    PubMed

    Meng, Fanfei; Asghar, Sajid; Gao, Shiya; Su, Zhigui; Song, Jue; Huo, Meirong; Meng, Weidong; Ping, Qineng; Xiao, Yanyu

    2015-10-01

    In this study, a novel low density lipoprotein (LDL)-mimic nanostructured lipid carrier (NLC) modified with lactoferrin (Lf) and loaded with curcumin (Cur) was designed for brain-targeted delivery, and its effect on controlling the progression of Alzheimer's disease (AD) in rats was evaluated. NLC with the composition resembling the lipid portion of LDL was prepared by using solvent evaporation method. Lf was adsorbed onto the surface of NLC via electrostatic interaction to yield Lf modified-NLC (Lf-mNLC) as the LDL-mimic nanocarrier. In order to make sure more Lf was adsorbed on the surface of NLC, negatively charged carboxylated polyethylene glycol (100) monostearate (S100-COOH) was synthesized and anchored into NLC. Different levels of S100-COOH (0-0.02 mmol) and Lf modified NLC (0.5-2.5 mg/mL of Lf solution) were prepared and characterized. The uptake and potential cytotoxicities of different preparations were investigated in the brain capillary endothelial cells (BCECs). An AD model of rats was employed to evaluate the therapeutic effects of Lf-mNLC. The results indicate that Lf-mNLC with a high level of Lf showed the maximum uptake in BCECs (1.39 folds greater than NLC) as cellular uptake of Lf-mNLC by BCECs was found to be mediated by the Lf receptor. FRET studies showed Cur still wrapped inside NLC after uptake by BCECs, demonstrating stability of the carrier as it moved across the BBB. Ex vivo imaging studies exposed Lf-mNLC could effectively permeate BBB and preferentially accumulate in the brain (2.78 times greater than NLC). Histopathological evaluation confirmed superior efficacy of Lf-mNLC in controlling the damage associated with AD. In conclusion, Lf-mNLC is a promising drug delivery system for targeting therapy of brain disease. PMID:26162977

  18. Alzheimer's disease: relevant molecular and physiopathological events affecting amyloid-β brain balance and the putative role of PPARs.

    PubMed

    Zolezzi, Juan M; Bastías-Candia, Sussy; Santos, Manuel J; Inestrosa, Nibaldo C

    2014-01-01

    Alzheimer's disease (AD) is the most common form of age-related dementia. With the expected aging of the human population, the estimated morbidity of AD suggests a critical upcoming health problem. Several lines of research are focused on understanding AD pathophysiology, and although the etiology of the disease remains a matter of intense debate, increased brain levels of amyloid-β (Aβ) appear to be a critical event in triggering a wide range of molecular alterations leading to AD. It has become evident in recent years that an altered balance between production and clearance is responsible for the accumulation of brain Aβ. Moreover, Aβ clearance is a complex event that involves more than neurons and microglia. The status of the blood-brain barrier (BBB) and choroid plexus, along with hepatic functionality, should be considered when Aβ balance is addressed. Furthermore, it has been proposed that exposure to sub-toxic concentrations of metals, such as copper, could both directly affect these secondary structures and act as a seeding or nucleation core that facilitates Aβ aggregation. Recently, we have addressed peroxisomal proliferator-activated receptors (PPARs)-related mechanisms, including the direct modulation of mitochondrial dynamics through the PPARγ-coactivator-1α (PGC-1α) axis and the crosstalk with critical aging- and neurodegenerative-related cellular pathways. In the present review, we revise the current knowledge regarding the molecular aspects of Aβ production and clearance and provide a physiological context that gives a more complete view of this issue. Additionally, we consider the different structures involved in AD-altered Aβ brain balance, which could be directly or indirectly affected by a nuclear receptor (NR)/PPAR-related mechanism.

  19. Whole-brain patterns of 1H-magnetic resonance spectroscopy imaging in Alzheimer's disease and dementia with Lewy bodies

    PubMed Central

    Su, L; Blamire, A M; Watson, R; He, J; Hayes, L; O'Brien, J T

    2016-01-01

    Magnetic resonance spectroscopy has demonstrated metabolite changes in neurodegenerative disorders such as Alzheimer's disease (AD) and dementia with Lewy bodies (DLB); however, their pattern and relationship to clinical symptoms is unclear. To determine whether the spatial patterns of brain-metabolite changes in AD and DLB are regional or diffused, and to examine whether the key metabolite levels are associated with cognitive and non-cognitive symptoms, we acquired whole-brain spatially resolved 3T magnetic resonance spectroscopic imaging (MRSI) data from subjects with AD (N=36), DLB (N=35) and similarly aged controls (N=35). Voxel-wise measurement of N-acetylaspartate to creatine (NAA/Cr), choline to Cr (Cho/Cr), myo-inositol to Cr (mI/Cr) as well as glutamate and glutamine to Cr (Glx/Cr) ratios were determined using MRSI. Compared with controls, AD and DLB groups showed a significant decrease in most brain metabolites, with NAA/Cr, Cho/Cr and mI/Cr levels being reduced in posterior cingulate, thalamus, frontotemporal areas and basal ganglia. The Glx/Cr level was more widely decreased in DLB (posterior cingulate, hippocampus, temporal regions and caudate) than in AD (only in posterior cingulate). DLB was also associated with increased levels of Cho/Cr, NAA/Cr and mI/Cr in occipital regions. Changes in metabolism in the brain were correlated with cognitive and non-cognitive symptoms in the DLB but not in the AD group. The different patterns between AD and DLB may have implications for improving diagnosis, better understanding disease-specific neurobiology and targeting therapeutics. In addition, the study raised important questions about the role of occipital neuroinflammation and glial activation as well as the glutamatergic treatment in DLB. PMID:27576166

  20. Differences in structural covariance brain networks between behavioral variant frontotemporal dementia and Alzheimer's disease.

    PubMed

    Hafkemeijer, Anne; Möller, Christiane; Dopper, Elise G P; Jiskoot, Lize C; van den Berg-Huysmans, Annette A; van Swieten, John C; van der Flier, Wiesje M; Vrenken, Hugo; Pijnenburg, Yolande A L; Barkhof, Frederik; Scheltens, Philip; van der Grond, Jeroen; Rombouts, Serge A R B

    2016-03-01

    Disease-specific patterns of gray matter atrophy in Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) overlap with distinct structural covariance networks (SCNs) in cognitively healthy controls. This suggests that both types of dementia target specific structural networks. Here, we study SCNs in AD and bvFTD. We used structural magnetic resonance imaging data of 31 AD patients, 24 bvFTD patients, and 30 controls from two centers specialized in dementia. Ten SCNs were defined based on structural covariance of gray matter density using independent component analysis. We studied group differences in SCNs using F-tests, with Bonferroni corrected t-tests, adjusted for age, gender, and study center. Associations with cognitive performance were studied using linear regression analyses. Cross-sectional group differences were found in three SCNs (all P < 0.0025). In bvFTD, we observed decreased anterior cingulate network integrity compared with AD and controls. Patients with AD showed decreased precuneal network integrity compared with bvFTD and controls, and decreased hippocampal network and anterior cingulate network integrity compared with controls. In AD, we found an association between precuneal network integrity and global cognitive performance (P = 0.0043). Our findings show that AD and bvFTD target different SCNs. The comparison of both types of dementia showed decreased precuneal (i.e., default mode) network integrity in AD and decreased anterior cingulate (i.e., salience) network integrity in bvFTD. This confirms the hypothesis that AD and bvFTD have distinct anatomical networks of degeneration and shows that structural covariance gives valuable insights in the understanding of network pathology in dementia.

  1. Hierarchical brain tissue segmentation and its application in multiple sclerosis and Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Lei, Tianhu; Udupa, Jayaram K.; Moonis, Gul; Schwartz, Eric; Balcer, Laura

    2005-04-01

    Based on Fuzzy Connectedness (FC) object delineation principles and algorithms, a hierarchical brain tissue segmentation technique has been developed for MR images. After MR image background intensity inhomogeneity correction and intensity standardization, three FC objects for cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) are generated via FC object delineation, and an intracranial (IC) mask is created via morphological operations. Then, the IC mask is decomposed into parenchymal (BP) and CSF masks, while the BP mask is separated into WM and GM masks. WM mask is further divided into pure and dirty white matter masks (PWM and DWM). In Multiple Sclerosis studies, a severe white matter lesion (LS) mask is defined from DWM mask. Based on the segmented brain tissue images, a histogram-based method has been developed to find disease-specific, image-based quantitative markers for characterizing the macromolecular manifestation of the two diseases. These same procedures have been applied to 65 MS (46 patients and 19 normal subjects) and 25 AD (15 patients and 10 normal subjects) data sets, each of which consists of FSE PD- and T2-weighted MR images. Histograms representing standardized PD and T2 intensity distributions and their numerical parameters provide an effective means for characterizing the two diseases. The procedures are systematic, nearly automated, robust, and the results are reproducible.

  2. The levels of water-soluble and triton-soluble Aβ are increased in Alzheimer's disease brain

    PubMed Central

    Mc Donald, Jessica M.; Cairns, Nigel J.; Taylor-Reinwald, Lisa; Holtzman, David; Walsh, Dominic M.

    2012-01-01

    Although plaques composed of the amyloid β-protein (Aβ) are considered a defining feature of Alzheimer's disease (AD), they are also found in cognitively normal individuals and extensive evidence suggests that non-plaque, water-soluble forms of Aβ may play a role in AD pathogenesis. However, the relationship between the levels of water-soluble Aβ and the clinical severity of disease has never been investigated. Here, we present results of a pilot study designed to examine the levels of water-soluble forms of Aβ in brains of individuals who died at clinically distinct stages of AD. Using a serial extraction method, we also investigated the levels of triton-soluble and formic acid-soluble Aβ. We found that water-soluble and detergent-soluble Aβ monomer and SDS-stable dimer were elevated in AD and that the levels of water soluble Aβ did not increase with plaque pathology. These results support the notion that both water- and detergent-soluble Aβ are important in AD and are not simply released from plaques by mechanical disruption. Moreover, the fact that the levels of water- and triton-soluble Aβ were similar in very mild/mild AD and moderate/severe AD suggests that once a certain level of these species is attained, further accumulation is not necessary for the disease to progress. Consequently, therapeutic targeting of water-soluble Aβ should best benefit individuals in earliest phases of the disease process. PMID:22440675

  3. Reduced expression of NO-sensitive guanylyl cyclase in reactive astrocytes of Alzheimer disease, Creutzfeldt-Jakob disease, and multiple sclerosis brains.

    PubMed

    Baltrons, María Antonia; Pifarré, Paula; Ferrer, Isidre; Carot, José Miguel; García, Agustina

    2004-12-01

    In Alzheimer's disease (AD) brains increased NO synthase (NOS) expression is found in reactive astrocytes surrounding amyloid plaques. We have recently shown that treatment with beta-amyloid peptides or IL-1beta down-regulates NO-sensitive soluble guanylyl cyclase (sGC) in cultured astrocytes and in adult rat brain. In this work, we have examined sGC activity and expression in postmortem brain tissue of AD patients and matched controls. No significant alteration was observed in basal or NO-stimulated sGC activity, nor in sGC beta1 and alpha1 subunit levels in cortical extracts of AD brains. Immunohistochemistry showed intense and widespread labeling of sGC beta1 in cortical and hippocampal neurons and white matter fibrillar astrocytes, while grey matter astrocytes were faintly stained. In AD, expression of sGC in neurons and fibrillar astrocytes is not altered but is markedly reduced in reactive astrocytes surrounding amyloid plaques. Immunostaining for sGC beta1 was also lacking in reactive astrocytes in cortex and subcortical white matter in Creutzfeldt-Jakob disease brains and in subacute and chronic plaques in multiple sclerosis (MS) brains. Thus, induction of astrocyte reactivity is associated with decreased capacity to generate cGMP in response to NO both in vitro and in vivo. This effect may be related to the development of the astroglial inflammatory response. PMID:15571982

  4. Immunotherapy for Alzheimer's disease.

    PubMed

    Farlow, Martin R; Brosch, Jared R

    2013-08-01

    The immune system plays a significant role in Alzheimer disease (AD). β-Amyloid deposition in the cortex is thought to be an initiating event in AD and the widely believed amyloid hypothesis proposes removal of amyloid may delay disease progression. Human trials of active or passive immune agents have failed to show benefit and increased adverse events of vasogenic edema and microhemorrhages. Evidence suggests the illness may be too advanced by the time patients are symptomatic with dementia. Future directions include better understanding of how and where immunotherapies should be targeted and treating patients at earlier stages of the illness.

  5. Advanced brain aging: relationship with epidemiologic and genetic risk factors, and overlap with Alzheimer disease atrophy patterns.

    PubMed

    Habes, M; Janowitz, D; Erus, G; Toledo, J B; Resnick, S M; Doshi, J; Van der Auwera, S; Wittfeld, K; Hegenscheid, K; Hosten, N; Biffar, R; Homuth, G; Völzke, H; Grabe, H J; Hoffmann, W; Davatzikos, C

    2016-01-01

    We systematically compared structural imaging patterns of advanced brain aging (ABA) in the general-population, herein defined as significant deviation from typical BA to those found in Alzheimer disease (AD). The hypothesis that ABA would show different patterns of structural change compared with those found in AD was tested via advanced pattern analysis methods. In particular, magnetic resonance images of 2705 participants from the Study of Health in Pomerania (aged 20-90 years) were analyzed using an index that captures aging atrophy patterns (Spatial Pattern of Atrophy for Recognition of BA (SPARE-BA)), and an index previously shown to capture atrophy patterns found in clinical AD (Spatial Patterns of Abnormality for Recognition of Early Alzheimer's Disease (SPARE-AD)). We studied the association between these indices and risk factors, including an AD polygenic risk score. Finally, we compared the ABA-associated atrophy with typical AD-like patterns. We observed that SPARE-BA had significant association with: smoking (P<0.05), anti-hypertensive (P<0.05), anti-diabetic drug use (men P<0.05, women P=0.06) and waist circumference for the male cohort (P<0.05), after adjusting for age. Subjects with ABA had spatially extensive gray matter loss in the frontal, parietal and temporal lobes (false-discovery-rate-corrected q<0.001). ABA patterns of atrophy were partially overlapping with, but notably deviating from those typically found in AD. Subjects with ABA had higher SPARE-AD values; largely due to the partial spatial overlap of associated patterns in temporal regions. The AD polygenic risk score was significantly associated with SPARE-AD but not with SPARE-BA. Our findings suggest that ABA is likely characterized by pathophysiologic mechanisms that are distinct from, or only partially overlapping with those of AD. PMID:27045845

  6. Advanced brain aging: relationship with epidemiologic and genetic risk factors, and overlap with Alzheimer disease atrophy patterns

    PubMed Central

    Habes, M; Janowitz, D; Erus, G; Toledo, J B; Resnick, S M; Doshi, J; Van der Auwera, S; Wittfeld, K; Hegenscheid, K; Hosten, N; Biffar, R; Homuth, G; Völzke, H; Grabe, H J; Hoffmann, W; Davatzikos, C

    2016-01-01

    We systematically compared structural imaging patterns of advanced brain aging (ABA) in the general-population, herein defined as significant deviation from typical BA to those found in Alzheimer disease (AD). The hypothesis that ABA would show different patterns of structural change compared with those found in AD was tested via advanced pattern analysis methods. In particular, magnetic resonance images of 2705 participants from the Study of Health in Pomerania (aged 20–90 years) were analyzed using an index that captures aging atrophy patterns (Spatial Pattern of Atrophy for Recognition of BA (SPARE-BA)), and an index previously shown to capture atrophy patterns found in clinical AD (Spatial Patterns of Abnormality for Recognition of Early Alzheimer's Disease (SPARE-AD)). We studied the association between these indices and risk factors, including an AD polygenic risk score. Finally, we compared the ABA-associated atrophy with typical AD-like patterns. We observed that SPARE-BA had significant association with: smoking (P<0.05), anti-hypertensive (P<0.05), anti-diabetic drug use (men P<0.05, women P=0.06) and waist circumference for the male cohort (P<0.05), after adjusting for age. Subjects with ABA had spatially extensive gray matter loss in the frontal, parietal and temporal lobes (false-discovery-rate-corrected q<0.001). ABA patterns of atrophy were partially overlapping with, but notably deviating from those typically found in AD. Subjects with ABA had higher SPARE-AD values; largely due to the partial spatial overlap of associated patterns in temporal regions. The AD polygenic risk score was significantly associated with SPARE-AD but not with SPARE-BA. Our findings suggest that ABA is likely characterized by pathophysiologic mechanisms that are distinct from, or only partially overlapping with those of AD. PMID:27045845

  7. Memory loss in Alzheimer's disease.

    PubMed

    Jahn, Holger

    2013-12-01

    Loss of memory is among the first symptoms reported by patients suffering from Alzheimer's disease (AD) and by their caretakers. Working memory and long-term declarative memory are affected early during the course of the disease. The individual pattern of impaired memory functions correlates with parameters of structural or functional brain integrity. AD pathology interferes with the formation of memories from the molecular level to the framework of neural networks. The investigation of AD memory loss helps to identify the involved neural structures, such as the default mode network, the influence of epigenetic and genetic factors, such as ApoE4 status, and evolutionary aspects of human cognition. Clinically, the analysis of memory assists the definition of AD subtypes, disease grading, and prognostic predictions. Despite new AD criteria that allow the earlier diagnosis of the disease by inclusion of biomarkers derived from cerebrospinal fluid or hippocampal volume analysis, neuropsychological testing remains at the core of AD diagnosis.

  8. The Impact of Docosahexaenoic Acid on Alzheimer's Disease: Is There a Role of the Blood-Brain Barrier?

    PubMed

    Pan, Yijun; Khalil, Hanan; Nicolazzo, Joseph A

    2015-01-01

    There currently is no cure or established preventative treatment for Alzheimer's disease (AD). Considering the increasing aging population and the subsequent high prevalence of AD worldwide, identifying a cost-effective way to prevent AD is an essential unmet medical need. Relative to healthy human brain samples, postmortem AD brain samples have been shown to exhibit lower docosahexaenoic acid (DHA) levels, an essential polyunsaturated fatty acid required for normal neuronal function. However, findings from different studies are controversial and it is not clear whether this alteration in DHA brain levels is a cause or consequence of AD. Animal studies have also demonstrated that administration of DHA can alleviate the underlying pathophysiology of AD, including but not limited to amyloid pathology, tau pathology, and neuroinflammation. Moreover, DHA has been suggested to exert cognitive-enhancing effects and epidemiological studies have suggested that regular consumption of fish or omega-3 fatty acid enriched diets can attenuate the cognitive decline in AD and/or lower the risk of developing AD. However, the beneficial effects of DHA in AD have not been clearly demonstrated by current human randomised-control trials. In addition, the underlying reasons for the lower brain levels of DHA in AD remain to be fully characterised. However, given that the brain has limited capacity to produce DHA de novo and obtains DHA from the plasma, one plausible explanation for the lower brain levels of DHA in AD is reduced bloodbrain barrier (BBB) transport of this fatty acid in AD, as has been reported in one mouse model of AD. Unfortunately, the actual mechanisms governing the BBB transport of DHA in healthy conditions are not clearly understood, complicating the relationship between reduced BBB transport of DHA, attenuated DHA brain levels and AD pathology. The purpose of this review, therefore, is to summarise the findings of the biochemical, functional and epidemiological

  9. The Brain Hepatocyte Growth Factor/c-Met Receptor System: A New Target for the Treatment of Alzheimer's Disease.

    PubMed

    Wright, John W; Harding, Joseph W

    2015-01-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disease increasing in frequency as life expectancy of the world's population increases. There are an estimated 5 million diagnosed AD patients in the U.S. and 16 million worldwide with no adequate treatment presently available. New therapeutic approaches are needed to slow, and hopefully reverse, disease progression. This review summarizes available information regarding an overlooked therapeutic target that may offer a treatment to slow and hopefully halt AD, namely the hepatocyte growth factor (HGF)/c-Met receptor system. Activation of the c-Met receptor stimulates mitogenesis, motogenesis, morphogenesis, the ability to mediate stem cell differentiation and neurogenesis, and protects against tissue insults in a wide range of cells including neurons. This growth factor system has recently been shown to induce dendritic arborization and synaptogenesis when stimulated by a newly developed angiotensin-based analogue, N-hexanoic-Tyr-Ile-(6) amino hexanoic amide (Dihexa). This small molecule was derived from the pre-prototype molecule Nle1-angiotensin IV and has shown promise in facilitating the formation of new functional synaptic connections and augmenting memory consolidation in animal models of AD. Dihexa is a first-in-class compound that is orally active, penetrates the blood-brain barrier, and facilitates memory consolidation and retrieval. This angiotensin-based small molecule may be efficacious as a treatment for AD.

  10. Changes of several brain receptor complexes in the cerebral cortex of patients with Alzheimer disease: probable new potential pharmaceutical targets.

    PubMed

    Falsafi, Soheil Keihan; Roßner, Steffen; Ghafari, Maryam; Groessl, Michael; Morawski, Markus; Gerner, Christopher; Lubec, Gert

    2014-01-01

    Although Alzheimer disease (AD) has been linked to defects in major brain receptors, studies thus far have been limited to the determination of receptor subunits or specific ligand binding studies. However, the availability of current technology enables the determination and quantification of brain receptor complexes. Thus, we examined levels of native receptor complexes in the brains of patients with AD. Cortical tissue was obtained from control subjects (n = 12 females and 12 males) and patients with AD (n = 12 females and 12 males) within a 3-h postmortem time period. The tissues were kept frozen until further biochemical analyses. Membrane proteins were extracted and subsequently enriched by ultracentrifugation using a sucrose gradient. Membrane proteins were then electrophoresed onto native gels and immunoblotted using antibodies against individual brain receptors. We found that the levels were comparable for complexes containing GluR2, GluR3 and GluR4 as well as 5-HT1A. Moreover, the levels of complexes containing muscarinic AChR M1, NR1 and GluR1 were significantly increased in male patients with AD. Nicotinic AChRs 4 and 7 as well as dopaminergic receptors D1 and D2 were also increased in males and females with AD. These findings reveal a pattern of altered receptor complex levels that may contribute to the deterioration of the concerted activity of these receptors and thus result in cognitive deficits observed in patients with AD. It should be emphasised that receptor complexes function as working units rather than individual subunits. Thus, the receptor deficits identified may be relevant for the design of experimental therapies. Therefore, specific pharmacological modulation of these receptors is within the pharmaceutical repertoire.

  11. Plasma protein biomarkers of Alzheimer's disease endophenotypes in asymptomatic older twins: early cognitive decline and regional brain volumes.

    PubMed

    Kiddle, S J; Steves, C J; Mehta, M; Simmons, A; Xu, X; Newhouse, S; Sattlecker, M; Ashton, N J; Bazenet, C; Killick, R; Adnan, J; Westman, E; Nelson, S; Soininen, H; Kloszewska, I; Mecocci, P; Tsolaki, M; Vellas, B; Curtis, C; Breen, G; Williams, S C R; Lovestone, S; Spector, T D; Dobson, R J B

    2015-06-16

    There is great interest in blood-based markers of Alzheimer's disease (AD), especially in its pre-symptomatic stages. Therefore, we aimed to identify plasma proteins whose levels associate with potential markers of pre-symptomatic AD. We also aimed to characterise confounding by genetics and the effect of genetics on blood proteins in general. Panel-based proteomics was performed using SOMAscan on plasma samples from TwinsUK subjects who are asymptomatic for AD, measuring the level of 1129 proteins. Protein levels were compared with 10-year change in CANTAB-paired associates learning (PAL; n = 195), and regional brain volumes (n = 34). Replication of proteins associated with regional brain volumes was performed in 254 individuals from the AddNeuroMed cohort. Across all the proteins measured, genetic factors were found to explain ~26% of the variability in blood protein levels on average. The plasma level of the mitogen-activated protein kinase (MAPK) MAPKAPK5 protein was found to positively associate with the 10-year change in CANTAB-PAL in both the individual and twin difference context. The plasma level of protein MAP2K4 was found to suggestively associate negatively (Q < 0.1) with the volume of the left entorhinal cortex. Future studies will be needed to assess the specificity of MAPKAPK5 and MAP2K4 to eventual conversion to AD.

  12. Plasma protein biomarkers of Alzheimer's disease endophenotypes in asymptomatic older twins: early cognitive decline and regional brain volumes

    PubMed Central

    Kiddle, S J; Steves, C J; Mehta, M; Simmons, A; Xu, X; Newhouse, S; Sattlecker, M; Ashton, N J; Bazenet, C; Killick, R; Adnan, J; Westman, E; Nelson, S; Soininen, H; Kloszewska, I; Mecocci, P; Tsolaki, M; Vellas, B; Curtis, C; Breen, G; Williams, S C R; Lovestone, S; Spector, T D; Dobson, R J B

    2015-01-01

    There is great interest in blood-based markers of Alzheimer's disease (AD), especially in its pre-symptomatic stages. Therefore, we aimed to identify plasma proteins whose levels associate with potential markers of pre-symptomatic AD. We also aimed to characterise confounding by genetics and the effect of genetics on blood proteins in general. Panel-based proteomics was performed using SOMAscan on plasma samples from TwinsUK subjects who are asymptomatic for AD, measuring the level of 1129 proteins. Protein levels were compared with 10-year change in CANTAB-paired associates learning (PAL; n=195), and regional brain volumes (n=34). Replication of proteins associated with regional brain volumes was performed in 254 individuals from the AddNeuroMed cohort. Across all the proteins measured, genetic factors were found to explain ~26% of the variability in blood protein levels on average. The plasma level of the mitogen-activated protein kinase (MAPK) MAPKAPK5 protein was found to positively associate with the 10-year change in CANTAB-PAL in both the individual and twin difference context. The plasma level of protein MAP2K4 was found to suggestively associate negatively (Q<0.1) with the volume of the left entorhinal cortex. Future studies will be needed to assess the specificity of MAPKAPK5 and MAP2K4 to eventual conversion to AD. PMID:26080319

  13. Brain microstructure reveals early abnormalities more than two years prior to clinical progression from mild cognitive impairment to Alzheimer's disease.

    PubMed

    Douaud, Gwenaëlle; Menke, Ricarda A L; Gass, Achim; Monsch, Andreas U; Rao, Anil; Whitcher, Brandon; Zamboni, Giovanna; Matthews, Paul M; Sollberger, Marc; Smith, Stephen

    2013-01-30

    Diffusion imaging is a promising marker of microstructural damage in neurodegenerative disorders, but interpretation of its relationship with underlying neuropathology can be complex. Here, we examined both volumetric and brain microstructure abnormalities in 13 amnestic patients with mild cognitive impairment (MCI), who progressed to probable Alzheimer's disease (AD) no earlier than 2 years after baseline scanning, in order to focus on early, and hence more sensitive, imaging markers. We compared them to 22 stable amnestic MCI patients with similar cognitive performance and episodic memory impairment but who did not show progression of symptoms for at least 3 years. Significant group differences were mainly found in the volume and microstructure of the left hippocampus, while white matter group differences were also found in the body of the fornix, left fimbria, and superior longitudinal fasciculus (SLF). Diffusion index abnormalities in the SLF were the sign of a subtle microstructural injury not detected by standard atrophy measures in the corresponding gray matter regions. The microstructural measure obtained in the left hippocampus using diffusion imaging showed the most substantial differences between the two groups and was the best single predictor of future progression to AD. An optimal prediction model (91% accuracy, 85% sensitivity, 96% specificity) was obtained by combining MRI measures and CSF protein biomarkers. These results highlight the benefit of using the information of brain microstructural damage, in addition to traditional gray matter volume, to detect early, subtle abnormalities in MCI prior to clinical progression to probable AD and, in combination with CSF markers, to accurately predict such progression.

  14. Advanced glycation end products are mitogenic signals and trigger cell cycle reentry of neurons in Alzheimer's disease brain.

    PubMed

    Kuhla, Angela; Ludwig, Sophie C; Kuhla, Björn; Münch, Gerald; Vollmar, Brigitte

    2015-02-01

    Neurons that reenter the cell cycle die rather than divide, a phenomenon that is associated with neurodegeneration in Alzheimer's disease (AD). Reexpression of cell-cycle related genes in differentiated neurons in AD might be rooted in aberrant mitogenic signaling. Because microglia and astroglia proliferate in the vicinity of amyloid plaques, it is likely that plaque components or factors secreted from plaque-activated glia induce neuronal mitogenic signaling. Advanced glycation end products (AGEs), protein-bound oxidation products of sugar, might be one of those mitogenic compounds. Cyclin D1 positive neurons are colocalized with AGEs or directly surrounded by extracellular AGE deposits in AD brain. However, a direct proof of DNA replication in these cells has been missing. Here, we report by using fluorescent in situ hybridization that consistent with the expression of cell cycle proteins, hyperploid neuronal cells are in colocalization with AGE staining in AD brains but not in nondemented controls. To complement human data, we used apolipoprotein E-deficient mice as model of neurodegeneration and showed that increased oxidative stress caused an intensified neuronal deposition of AGEs, being accompanied by an activation of the MAPK cascade via RAGE. This cascade, in turn, induced the expression of cyclin D1 and DNA replication. In addition, reduction of oxidative stress by application of α-lipoic acid decreased AGE accumulations, and this decrease was accompanied by a reduction in cell cycle reentry and a more euploid neuronal genome.

  15. Brain Serotonergic and Noradrenergic Deficiencies in Behavioral Variant Frontotemporal Dementia Compared to Early-Onset Alzheimer's Disease.

    PubMed

    Vermeiren, Yannick; Janssens, Jana; Aerts, Tony; Martin, Jean-Jacques; Sieben, Anne; Van Dam, Debby; De Deyn, Peter P

    2016-06-15

    Routinely prescribed psychoactive drugs in behavioral variant frontotemporal dementia (FTD) for improvement of (non)cognitive symptoms are primarily based on monoamine replacement or augmentation strategies. These were, however, initially intended to symptomatically treat other degenerative, behavioral, or personality disorders, and thus lack disease specificity. Moreover, current knowledge on brain monoaminergic neurotransmitter deficiencies in this presenile disorder is scarce, particularly with reference to changes in Alzheimer's disease (AD). The latter hence favors neurochemical comparison studies in order to elucidate the monoaminergic underpinnings of FTD compared to early-onset AD, which may contribute to better pharmacotherapy. Therefore, frozen brain samples, i.e., Brodmann area (BA) 6/8/9/10/11/12/22/24/46, amygdala, and hippocampus, of 10 neuropathologically confirmed FTD, AD, and control subjects were analyzed by means of reversed-phase high-performance liquid chromatography. Levels of serotonergic, dopaminergic, and noradrenergic compounds were measured. In nine brain areas, serotonin (5-HT) concentrations were significantly increased in FTD compared to AD patients, while 5-hydroxyindoleacetic acid/5-HT ratios were decreased in eight regions, also compared to controls. Furthermore, in all regions, noradrenaline (NA) levels were significantly higher, and 3-methoxy-4-hydroxyphenylglycol/NA ratios were significantly lower in FTD than in AD and controls. Contrarily, significantly higher dopamine (DA) levels and reduced homovanillic acid/DA ratios were only found in BA12 and BA46. Results indicate that FTD is defined by distinct serotonergic and noradrenergic deficiencies. Additional research regarding the interactions between both monoaminergic networks is required. Similarly, clinical trials investigating the effects of 5-HT1A receptor antagonists or NA-modulating agents, such as α1/2/β1-blockers, seem to have a rationale and should be considered. PMID

  16. [Diabetes mellitus and Alzheimer's disease].

    PubMed

    Salacz, Pál; Csibri, Eva

    2011-03-27

    The incidence of Alzheimer's disease and diabetes is increasing with age. Thus, in light of demographic change and aging societies, they are becoming a growing issue for public health. Further, there are linkages between the two diseases. In particular, risk assessment studies suggest that type 2 diabetes mellitus is a risk factor of Alzheimer's disease. Hence, even though Alzheimer's disease can only be influenced to a limited extent, optimal treatment of diabetes mellitus may have also a positive effect on Alzheimer's disease. While the relationship between the two diseases is not yet completely clear, in addition to the known vascular effects of diabetes mellitus recent results shed light on central nervous system effects directly influencing the neurodegenerative process. Treatment of central insulin resistance, a phenomenon explored in recent years, may be a promising avenue, not only in addressing metabolic disorder, but also Alzheimer's disease.

  17. Noradrenergic dysfunction in Alzheimer's disease

    PubMed Central

    Gannon, Mary; Che, Pulin; Chen, Yunjia; Jiao, Kai; Roberson, Erik D.; Wang, Qin

    2015-01-01

    The brain noradrenergic system supplies the neurotransmitter norepinephrine throughout the brain via widespread efferent projections, and plays a pivotal role in modulating cognitive activities in the cortex. Profound noradrenergic degeneration in Alzheimer's disease (AD) patients has been observed for decades, with recent research suggesting that the locus coeruleus (where noradrenergic neurons are mainly located) is a predominant site where AD-related pathology begins. Mounting evidence indicates that the loss of noradrenergic innervation greatly exacerbates AD pathogenesis and progression, although the precise roles of noradrenergic components in AD pathogenesis remain unclear. The aim of this review is to summarize current findings on noradrenergic dysfunction in AD, as well as to point out deficiencies in our knowledge where more research is needed. PMID:26136654

  18. Elevated risk of type 2 diabetes for development of Alzheimer disease: a key role for oxidative stress in brain.

    PubMed

    Butterfield, D Allan; Di Domenico, Fabio; Barone, Eugenio

    2014-09-01

    Alzheimer disease (AD) is the most common form of dementia among the elderly and is characterized by progressive loss of memory and cognition. Epidemiological data show that the incidence of AD increases with age and doubles every 5 years after 65 years of age. From a neuropathological point of view, amyloid-β-peptide (Aβ) leads to senile plaques, which, together with hyperphosphorylated tau-based neurofibrillary tangles and synapse loss, are the principal pathological hallmarks of AD. Aβ is associated with the formation of reactive oxygen (ROS) and nitrogen (RNS) species, and induces calcium-dependent excitotoxicity, impairment of cellular respiration, and alteration of synaptic functions associated with learning and memory. Oxidative stress was found to be associated with type 2 diabetes mellitus (T2DM), which (i) represents another prevalent disease associated with obesity and often aging, and (ii) is considered to be a risk factor for AD development. T2DM is characterized by high blood glucose levels resulting from increased hepatic glucose production, impaired insulin production and peripheral insulin resistance, which close resemble to the brain insulin resistance observed in AD patients. Furthermore, growing evidence suggests that oxidative stress plays a pivotal role in the development of insulin resistance and vice versa. This review article provides molecular aspects and the pharmacological approaches from both preclinical and clinical data interpreted from the point of view of oxidative stress with the aim of highlighting progresses in this field.

  19. Genomic mosaicism with increased amyloid precursor protein (APP) gene copy number in single neurons from sporadic Alzheimer's disease brains

    PubMed Central

    Bushman, Diane M; Kaeser, Gwendolyn E; Siddoway, Benjamin; Westra, Jurgen W; Rivera, Richard R; Rehen, Stevens K; Yung, Yun C; Chun, Jerold

    2015-01-01

    Previous reports have shown that individual neurons of the brain can display somatic genomic mosaicism of unknown function. In this study, we report altered genomic mosaicism in single, sporadic Alzheimer's disease (AD) neurons characterized by increases in DNA content and amyloid precursor protein (APP) gene copy number. AD cortical nuclei displayed large variability with average DNA content increases of ∼8% over non-diseased controls that were unrelated to trisomy 21. Two independent single-cell copy number analyses identified amplifications at the APP locus. The use of single-cell qPCR identified up to 12 copies of APP in sampled neurons. Peptide nucleic acid (PNA) probes targeting APP, combined with super-resolution microscopy detected primarily single fluorescent signals of variable intensity that paralleled single-cell qPCR analyses. These data identify somatic genomic changes in single neurons, affecting known and unknown loci, which are increased in sporadic AD, and further indicate functionality for genomic mosaicism in the CNS. DOI: http://dx.doi.org/10.7554/eLife.05116.001 PMID:25650802

  20. Elevated Risk of Type 2 Diabetes for Development of Alzheimer Disease: a Key Role for Oxidative Stress in Brain

    PubMed Central

    Butterfield, D. Allan; Di Domenico, Fabio; Barone, Eugenio

    2014-01-01

    Alzheimer disease (AD) is the most common form of dementia among the elderly and is characterized by progressive loss of memory and cognition. Epidemiological data show that the incidence of AD increases with age and doubles every 5 years after 65 years of age. From a neuropathological point of view, amyloid-β-peptide (Aβ) leads to senile plaques, which, together with hyperphosphorylated tau-based neurofibrillary tangles and synapse loss, are the principal pathological hallmarks of AD. Aβ is associated with the formation of reactive oxygen (ROS) and nitrogen (RNS) species, and induces calcium-dependent excitotoxicity, impairment of cellular respiration, and alteration of synaptic functions associated with learning and memory. Oxidative stress was found to be associated with type 2 diabetes mellitus (T2DM), which (i) represents another prevalent disease associated with obesity and often aging, and (ii) is considered to be a risk factor for AD development. T2DM is characterized by high blood glucose levels resulting from increased hepatic glucose production, impaired insulin production and peripheral insulin resistance, which close resemble to the brain insulin resistance observed in AD patients. Furthermore, growing evidence suggest that oxidative stress play a pivotal role in the development of insulin resistance and vice versa. This review article provides molecular aspects and the pharmacological approaches from both preclinical and clinical data and interpreted from the point of view of oxidative stress with the aim to highlight progresses in this field. PMID:24949886

  1. A Food and Drug Administration-approved Asthma Therapeutic Agent Impacts Amyloid β in the Brain in a Transgenic Model of Alzheimer Disease*

    PubMed Central

    Hori, Yukiko; Takeda, Shuko; Cho, Hansang; Wegmann, Susanne; Shoup, Timothy M.; Takahashi, Kazue; Irimia, Daniel; Elmaleh, David R.; Hyman, Bradley T.; Hudry, Eloise

    2015-01-01

    Interfering with the assembly of Amyloid β (Aβ) peptides from monomer to oligomeric species and fibrils or promoting their clearance from the brain are targets of anti-Aβ-directed therapies in Alzheimer disease. Here we demonstrate that cromolyn sodium (disodium cromoglycate), a Food and Drug Administration-approved drug already in use for the treatment of asthma, efficiently inhibits the aggregation of Aβ monomers into higher-order oligomers and fibrils in vitro without affecting Aβ production. In vivo, the levels of soluble Aβ are decreased by over 50% after only 1 week of daily intraperitoneally administered cromolyn sodium. Additional in vivo microdialysis studies also show that this compound decreases the half-life of soluble Aβ in the brain. These data suggest a clear effect of a peripherally administered, Food and Drug Administration-approved medication on Aβ economy, supporting further investigation of the potential long-term efficacy of cromolyn sodium in Alzheimer disease. PMID:25468905

  2. Increased O-GlcNAc Levels Correlate with Decreased O-GlcNAcase Levels in Alzheimer Disease Brain

    PubMed Central

    Förster, Sarah; Welleford, Andrew S.; Triplett, Judy C.; Sultana, Rukhsana; Schmitz, Brigitte; Butterfield, D. Allan

    2014-01-01

    The potential role of the posttranslational modification of proteins with O-linked N-acetyl-β-D-glucosamine (O-GlcNAc) in the pathogenesis of Alzheimer disease (AD) has been studied extensively, yet the exact function of O-GlcNAc in AD remains elusive. O-GlcNAc cycling is facilitated by only two highly conserved enzymes: O-GlcNAc transferase (OGT) catalyzes the addition, while O-GlcNAcase (OGA) catalyzes the removal of GlcNAc from proteins. Studies analyzing global O-GlcNAc levels in AD brain have produced inconsistent results and the reasons for altered O-GlcNAcylation in AD are still poorly understood. In this study, we show a 1.2 fold increase in cytosolic protein O-GlcNAc modification in AD brain when compared to age-matched controls. Interestingly, O-GlcNAc changes seem to be attributable to differential modification of a few individual proteins. While our finding of augmented O-GlcNAcylation concurs with some reports, it is contrary to others demonstrating decreased O-GlcNAc levels in AD brain. These conflicting results emphasize the need for further studies providing conclusive evidence on the subject of O-GlcNAcylation in AD. We further demonstrate that, while OGT protein levels are unaffected in AD, OGA protein levels are significantly decreased to 75 % of those in control samples. In addition, augmented protein O-GlcNAc modification correlates to decreased OGA protein levels in AD subjects. While OGA inhibitors are already being tested for AD treatment, our results provide a strong indication that the general subject of O-GlcNAcylation and specifically its regulation by OGA and OGT in AD need further investigation to conclusively elucidate its potential role in AD pathogenesis and treatment. PMID:24859566

  3. Harnessing the power of gene microarrays for the study of brain aging and Alzheimer's disease: statistical reliability and functional correlation.

    PubMed

    Blalock, E M; Chen, K-C; Stromberg, A J; Norris, C M; Kadish, I; Kraner, S D; Porter, N M; Landfield, P W

    2005-11-01

    During normal brain aging, numerous alterations develop in the physiology, biochemistry and structure of neurons and glia. Aging changes occur in most brain regions and, in the hippocampus, have been linked to declining cognitive performance in both humans and animals. Age-related changes in hippocampal regions also may be harbingers of more severe decrements to come from neurodegenerative disorders such as Alzheimer's disease (AD). However, unraveling the mechanisms underlying brain aging, AD and impaired function has been difficult because of the complexity of the networks that drive these aging-related changes. Gene microarray technology allows massively parallel analysis of most genes expressed in a tissue, and therefore is an important new research tool that potentially can provide the investigative power needed to address the complexity of brain aging/neurodegenerative processes. However, along with this new analytic power, microarrays bring several major bioinformatics and resource problems that frequently hinder the optimal application of this technology. In particular, microarray analyses generate extremely large and unwieldy data sets and are subject to high false positive and false negative rates. Concerns also have been raised regarding their accuracy and uniformity. Furthermore, microarray analyses can result in long lists of altered genes, most of which may be difficult to evaluate for functional relevance. These and other problems have led to some skepticism regarding the reliability and functional usefulness of microarray data and to a general view that microarray data should be validated by an independent method. Given recent progress, however, we suggest that the major problem for current microarray research is no longer validity of expression measurements, but rather, the reliability of inferences from the data, an issue more appropriately redressed by statistical approaches than by validation with a separate method. If tested using statistically

  4. Adipose-derived mesenchymal stem cell transplantation promotes adult neurogenesis in the brains of Alzheimer's disease mice

    PubMed Central

    Yan, Yufang; Ma, Tuo; Gong, Kai; Ao, Qiang; Zhang, Xiufang; Gong, Yandao

    2014-01-01

    In the present study, we transplanted adipose-derived mesenchymal stem cells into the hippocampi of APP/PS1 transgenic Alzheimer's disease model mice. Immunofluorescence staining revealed that the number of newly generated (BrdU+) cells in the subgranular zone of the dentate gyrus in the hippocampus was significantly higher in Alzheimer's disease mice after adipose-derived mesenchymal stem cell transplantation, and there was also a significant increase in the number of BrdU+/DCX+ neuroblasts in these animals. Adipose-derived mesenchymal stem cell transplantation enhanced neurogenic activity in the subventricular zone as well. Furthermore, adipose-derived mesenchymal stem cell transplantation reduced oxidative stress and alleviated cognitive impairment in the mice. Based on these findings, we propose that adipose-derived mesenchymal stem cell transplantation enhances endogenous neurogenesis in both the subgranular and subventricular zones in APP/PS1 transgenic Alzheimer's disease mice, thereby facilitating functional recovery. PMID:25206892

  5. Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease

    SciTech Connect

    Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J.

    2008-06-06

    Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease.

  6. Why Do We Get Alzheimer's Disease?

    SciTech Connect

    Wyss-Coray, Tony

    2006-01-02

    Neurodegenerative diseases and Alzheimer's disease (AD) in particular, are among the major health concerns of the elderly in industrialized societies. The cause of AD is unknown and no disease-modifying treatments are available. The disease is characterized clinically by a progressive dementia and pathologically by the accumulation of protein aggregates in the brain and a profound loss of nerve cells. It has also become clear recently that local immune responses are activated in the AD brain and may have a role in the disease. Our laboratory uses genetic mouse models to understand the disease process and to identify potential therapeutic targets.

  7. Why do we get Alzheimer's disease?

    SciTech Connect

    Wyss-Coray, Tony

    2006-10-02

    Neurodegenerative diseases and Alzheimer's disease (AD) in particular, are among the major health concerns of the elderly in industrialized societies. The cause of AD is unknown and no disease-modifying treatments are available. The disease is characterized clinically by a progressive dementia and pathologically by the accumulation of protein aggregates in the brain and a profound loss of nerve cells. It has also become clear recently that local immune responses are activated in the AD brain and may have a role in the disease. Our laboratory uses genetic mouse models to understand the disease process and to identify potential therapeutic targets.

  8. Alzheimer's Disease Beyond Abeta.

    PubMed

    Town, Terrence

    2010-05-01

    Many of the Alzheimer's disease (AD) clinical trials have made it far enough down the pipeline to allow conclusions about targeting the amyloid-beta peptide (Abeta) as a therapeutic approach. Based on these results, it is becoming clear that a multifocal approach to AD treatment is probably necessary. However, critical discussion beyond Abeta is necessary to enable the next wave of AD therapeutic targets. For this reason, the 2010 Keystone Symposium, 'Alzheimer's Disease Beyond Abeta', was organized by JoAnne McLaurin and Tony Wyss-Coray to spark topical discussion and debate. While researchers struggled to get beyond that ever-present pathognomonic feature of AD, new and exciting evidence was presented that raised our awareness of what is around the corner for next-generation AD therapeutics beyond Abeta. This report will describe some of the highlights from Copper Mountain Resort throughout the meeting period of 10-15 January 2010 in Colorado (USA). Despite illuminating scientific presentations and intense discussions, a number of important questions remain concerning the best biomarkers and targets to focus on, and when and how to therapeutically intervene. PMID:20429127

  9. A framework to understand the variations of PSD-95 expression in brain aging and in Alzheimer's disease.

    PubMed

    Savioz, Armand; Leuba, Geneviève; Vallet, Philippe G

    2014-11-01

    The postsynaptic density protein PSD-95 is a major element of synapses. PSD-95 is involved in aging, Alzheimer's disease (AD) and numerous psychiatric disorders. However, contradictory data about PSD-95 expression in aging and AD have been reported. Indeed in AD versus control brains PSD-95 varies according to regions, increasing in the frontal cortex, at least in a primary stage, and decreasing in the temporal cortex. In contrast, in transgenic mouse models of aging and AD PSD-95 expression is decreased, in behaviorally aged impaired versus unimpaired rodents it can decrease or increase and finally, it is increased in rodents grown in enriched environments. Different factors explain these contradictory results in both animals and humans, among others concomitant psychiatric endophenotypes, such as depression. The possible involvement of PSD-95 in reactive and/or compensatory mechanisms during AD progression is underscored, at least before the occurrence of important synaptic elimination. Thus, in AD but not in AD transgenic mice, enhanced expression might precede the diminution commonly observed in advanced aging. A two-compartments cell model, separating events taking place in cell bodies and synapses, is presented. Overall these data suggest that AD research will progress by untangling pathological from protective events, a prerequisite for effective therapeutic strategies.

  10. Age Progression of Neuropathological Markers in the Brain of the Chilean Rodent Octodon degus, a Natural Model of Alzheimer's Disease.

    PubMed

    Inestrosa, Nibaldo C; Ríos, Juvenal A; Cisternas, Pedro; Tapia-Rojas, Cheril; Rivera, Daniela S; Braidy, Nady; Zolezzi, Juan M; Godoy, Juan A; Carvajal, Francisco J; Ardiles, Alvaro O; Bozinovic, Francisco; Palacios, Adrián G; Sachdev, Perminder S

    2015-11-01

    Alzheimer's disease (AD) is the most common neurodegenerative disorder and the leading cause of age-related dementia worldwide. Several models for AD have been developed to provide information regarding the initial changes that lead to degeneration. Transgenic mouse models recapitulate many, but not all, of the features of AD, most likely because of the high complexity of the pathology. In this context, the validation of a wild-type animal model of AD that mimics the neuropathological and behavioral abnormalities is necessary. In previous studies, we have reported that the Chilean rodent Octodon degus could represent a natural model for AD. In the present work, we further describe the age-related neurodegeneration observed in the O. degus brain. We report some histopathological markers associated with the onset progression of AD, such as glial activation, increase in oxidative stress markers, neuronal apoptosis and the expression of the peroxisome proliferative-activated receptor γ coactivator-1α (PGC-1α). With these results, we suggest that the O. degus could represent a new model for AD research and a powerful tool in the search for therapeutic strategies against AD.

  11. Age Progression of Neuropathological Markers in the Brain of the Chilean Rodent Octodon degus, a Natural Model of Alzheimer's Disease.

    PubMed

    Inestrosa, Nibaldo C; Ríos, Juvenal A; Cisternas, Pedro; Tapia-Rojas, Cheril; Rivera, Daniela S; Braidy, Nady; Zolezzi, Juan M; Godoy, Juan A; Carvajal, Francisco J; Ardiles, Alvaro O; Bozinovic, Francisco; Palacios, Adrián G; Sachdev, Perminder S

    2015-11-01

    Alzheimer's disease (AD) is the most common neurodegenerative disorder and the leading cause of age-related dementia worldwide. Several models for AD have been developed to provide information regarding the initial changes that lead to degeneration. Transgenic mouse models recapitulate many, but not all, of the features of AD, most likely because of the high complexity of the pathology. In this context, the validation of a wild-type animal model of AD that mimics the neuropathological and behavioral abnormalities is necessary. In previous studies, we have reported that the Chilean rodent Octodon degus could represent a natural model for AD. In the present work, we further describe the age-related neurodegeneration observed in the O. degus brain. We report some histopathological markers associated with the onset progression of AD, such as glial activation, increase in oxidative stress markers, neuronal apoptosis and the expression of the peroxisome proliferative-activated receptor γ coactivator-1α (PGC-1α). With these results, we suggest that the O. degus could represent a new model for AD research and a powerful tool in the search for therapeutic strategies against AD. PMID:25351914

  12. In Alzheimer's disease, hypometabolism in low-amyloid brain regions may be a functional consequence of pathologies in connected brain regions.

    PubMed

    Klupp, Elisabeth; Förster, Stefan; Grimmer, Timo; Tahmasian, Masoud; Yakushev, Igor; Sorg, Christian; Yousefi, Behrooz H; Drzezga, Alexander

    2014-06-01

    In patients with Alzheimer's disease (AD), prominent hypometabolism has been observed in brain regions with minor amyloid load. These hypometabolism-only (HO) areas cannot be explained merely as a consequence of local amyloid toxicity. The aim of this multimodal imaging study was to explore whether such HO phenomenon may be related to pathologies in functionally connected, remote brain regions. Nineteen AD patients and 15 matched controls underwent examinations with [(11)C]PiB-PET and [(18)F]FDG-PET. Voxel-based statistical group comparisons were performed to obtain maps of significantly elevated amyloid burden and reduced cerebral glucose metabolism, respectively, in patients. An HO area was identified by subtraction of equally thresholded result maps (hypometabolism minus amyloid burden). To identify the network typically functionally connected to this HO area, it was used as a seed region for a functional connectivity analysis in resting-state functional magnetic resonance imaging data of 17 elderly healthy controls. The resulting intrinsic connectivity network (HO-ICN) was retransferred into the brains of AD patients to be able to analyze pathologies within this network in the positron emission tomography (PET) datasets. The most prominent HO area was detected in the left middle frontal gyrus of AD patients. The HO-ICN in healthy controls showed a major overlap with brain areas significantly affected by both amyloid deposition and hypometabolism in patients. This association was substantiated by the results of region-of-interest-based and voxel-wise correlation analyses, which revealed strong correlations between the degree of hypometabolism within the HO region and within the HO-ICN. These results support the notion that hypometabolism in brain regions not strongly affected by locoregional amyloid pathology may be related to ongoing pathologies in remote but functionally connected regions, that is, by reduced neuronal input from these regions. PMID:24870443

  13. Seizures in Alzheimer's disease.

    PubMed

    Born, H A

    2015-02-12

    Alzheimer's disease (AD) increases the risk for late-onset seizures and neuronal network abnormalities. An elevated co-occurrence of AD and seizures has been established in the more prevalent sporadic form of AD. Recent evidence suggests that nonconvulsive network abnormalities, including seizures and other electroencephalographic abnormalities, may be more commonly found in patients than previously thought. Patients with familial AD are at an even greater risk for seizures, which have been found in patients with mutations in PSEN1, PSEN2, or APP, as well as with APP duplication. This review also provides an overview of seizure and electroencephalography studies in AD mouse models. The amyloid-β (Aβ) peptide has been identified as a possible link between AD and seizures, and while Aβ is known to affect neuronal activity, the full-length amyloid precursor protein (APP) and other APP cleavage products may be important for the development and maintenance of cortical network hyperexcitability. Nonconvulsive epileptiform activity, such as seizures or network abnormalities that are shorter in duration but may occur with higher frequency, may contribute to cognitive impairments characteristic of AD, such as amnestic wandering. Finally, the review discusses recent studies using antiepileptic drugs to rescue cognitive deficits in AD mouse models and human patients. Understanding the mechanistic link between epileptiform activity and AD is a research area of growing interest. Further understanding of the connection between neuronal hyperexcitability and Alzheimer's as well as the potential role of epileptiform activity in the progression of AD will be beneficial for improving treatment strategies.

  14. A quantitative assessment of glycolipid and protein associated with paired helical filament preparations from Alzheimer's diseased brain.

    PubMed

    Goux, Warren J.; Liu, Bingcam; Shumburo, Abdurahman M.; Parikh, Samir; Sparkman, Dennis R.

    2001-10-01

    Protease resistant paired helical filaments (prcPHF) can be isolated from the brains of Alzheimer's diseased patients. A second type of PHF, A68 PHF, may be extracted in soluble form from brain homogenate and induced to form filaments in vitro. Here we use a variety of analytical techniques to assess the protein, carbohydrate and fatty acid composition of prcPHF and A68 PHF. High-field ^1H NMR of both PHF preparations display similar fatty acid and carbohydrate proton resonances, consistent with the presence of a structurally similar glycolipid. Carbohydrate analysis showed that both preparations contained greater than 82% less than 12% C16:1 was significantly lower in A68 PHF than in prcPHF, both preparations contained otherwise similar fatty acid profiles with the most abundant lipid component being oleic acid (C18:1, 29.3 +/- 9.0%) followed by palmitic (C16:0, 28.5 +/- 5.6%) 17.6 +/- 7.5%) preparations revealed a profile reasonably consistent with that previously determined for PHF-tau but significantly higher in glycine and lower in lysine than would be predicted from the cDNA sequence. On a weight per cent basis, protein accounted for about 51% A68 PHF samples but only about 10% Carbohydrate and fatty acid accounted for about 39% A68 PHF samples but 74% preparations showed strong correlations between the total amount of tau protein and fatty acid. These results suggest that a glycolipid component forms an integral part of the PHF structure.

  15. Potential fluid biomarkers for pathological brain changes in Alzheimer's disease: Implication for the screening of cognitive frailty

    PubMed Central

    Ruan, Qingwei; D'Onofrio, Grazia; Sancarlo, Daniele; Greco, Antonio; Yu, Zhuowei

    2016-01-01

    Cognitive frailty (CF) overlaps with early neuropathological alterations associated with aging-related major neurocognitive disorders, including Alzheimer's disease (AD). Fluid biomarkers for these pathological brain alterations allow for early diagnosis in the preclinical stages of AD, and for objective prognostic assessments in clinical intervention trials. These biomarkers may also be helpful in the screening of CF. The present study reviewed the literature and identified systematic reviews of cohort studies and other authoritative reports. The selection criteria for potentially suitable fluid biomarkers included: i) Frequent use in studies of fluid-derived markers and ii) evidence of novel measurement techniques for fluid-derived markers. The present study focused on studies that assessed these biomarkers in AD, mild cognitive impairment and non-AD demented subjects. At present, widely used fluid biomarkers include cerebrospinal fluid (CSF), total tau, phosphorylated tau and amyloid-β levels. With the development of novel measurement techniques and improvements in understanding regarding the mechanisms underlying aging-related major neurocognitive disorders, numerous novel biomarkers associated with various aspects of AD neuropathology are being explored. These include specific measurements of Aβ oligomer or monomer forms, tau proteins in the peripheral plasma and CSF, and novel markers of synaptic dysfunction, neuronal damage and apoptosis, neuronal activity alteration, neuroinflammation, blood brain barrier dysfunction, oxidative stress, metabolites, mitochondrial function and aberrant lipid metabolism. The proposed panels of fluid biomarkers may be useful in the early diagnosis of AD, prediction of the progression of AD from preclinical stages to the dementia stage, and the differentiation of AD from non-AD dementia. In combination with physical frailty, the present study surmised that these biomarkers may also be used as biomarkers for CF, thus contribute

  16. Assessing the cognitive impact of Alzheimer disease pathology and vascular burden in the aging brain: the Geneva experience.

    PubMed

    Giannakopoulos, Panteleimon; Gold, Gabriel; Kövari, Enikö; von Gunten, Armin; Imhof, Anouk; Bouras, Constantin; Hof, Patrick R

    2007-01-01

    The progressive development of Alzheimer disease (AD)-related lesions, such as neurofibrillary tangles (NFT), amyloid deposits and synaptic loss, and the occurrence of microvascular and small macrovascular pathology within the cerebral cortex are conspicuous neuropathologic features of brain aging. Recent neuropathologic studies strongly suggested that the clinical diagnosis of dementia depends more on the severity and topography of pathological changes than on the presence of a qualitative marker. However, several methodological problems, such as selection biases, case-control design, density-based measures and masking effects, of concomitant pathologies persisted. In recent years, we performed several clinicopathologic studies using stereological counting of AD lesions. In order to define the cognitive impact of lacunes and microvascular lesions, we also analyzed pure vascular cases without substantial AD pathology. Our data revealed that total NFT numbers in the CA1 field, cortical microinfarcts and subcortical gray matter lacunes were the stronger determinants of dementia. In contrast, the contribution of periventricular and subcortical white matter demyelinations had a modest cognitive effect even in rare cases with isolated microvascular pathology. Importantly, in cases with pure AD pathology, more than 50% of Clinical Dementia Rating scale variability was not explained by NFT, amyloid deposits and neuronal loss in the hippocampal formation. In cases with microvascular pathology or lacunes, this percentage was even lower. The present review summarizes our data in this field and discusses their relevance within the theoretical framework of the functional neuropathology of brain aging and with particular reference to the current efforts to develop standardized neuropathological criteria for mixed dementia. PMID:17036244

  17. Progenitor endothelial cell involvement in Alzheimer's disease

    SciTech Connect

    Budinger, Thomas F.

    2003-05-01

    There is compelling evidence that endothelial cells of the brain and periphery are dysfunctional in Alzheimer's Disease. There is evidence for a fundamental defect in, or abnormal aging of, endothelial progenitor cells in atherosclerosis. The possibility that endothelial cell defects are a primary cause for Alzheimer's Disease or other dementias can be researched by molecular and cell biology studies as well as cell trafficking studies using recently demonstrated molecular imaging methods. The evidence for abnormal endothelial function and the methods to explore this hypothesis are presented.

  18. Effect of Alzheimer Disease Risk on Brain Function During Self-Appraisal in Healthy Middle-Aged Adults

    PubMed Central

    Johnson, Sterling C.; Ries, Michele L.; Hess, Timothy M.; Carlsson, Cynthia M.; Gleason, Carey E.; Alexander, Andrew L.; Rowley, Howard A.; Asthana, Sanjay; Sager, Mark A.

    2009-01-01

    Context Recently asymptomatic middle-aged adult children of patients with Alzheimer Disease (AD) were found to exhibit fMRI deficits in the mesial temporal lobe during an encoding task. Whether this effect will be observed on other fMRI tasks is not yet known. This study examines the neural substrates of self-appraisal in people at risk for AD. Accurate appraisal of deficits is a problem for many AD patients, and prior fMRI studies of healthy young adults indicates that brain areas vulnerable to AD such as the anterior mesial temporal lobe and posterior cingulate are involved during self appraisal tasks. Objective To determine whether parental family history of AD (FH) or the ε4 allele of the Apolipoprotein E gene (APOE4) exert independent effects on brain function during self-appraisal. Design Cross-sectional factorial design in which APOE4 status (present/absent) was one factor, and FH status was the other. All participants received cognitive testing, genotyping and an fMRI task that required subjective self-appraisal (SA) decisions regarding trait adjective words in comparison to semantic decisions about the same words. Setting An academic medical center with a research-dedicated 3.0 Tesla MRI facility. Participants Cognitively normal middle-aged adults (N=110): 51 +FH; 59 −FH. Outcome measure Blood oxygen-dependent contrast measured with T2* weighted echo-planar imaging. Results FH and APOE4 status interacted in the posterior cingulate as well as left superior and medial frontal regions. There were main effects of FH (−FH > +FH) in left hippocampus, and ventral posterior cingulate. There were no main effects of APOE. Conclusion These results suggest that a parental history of AD may influence brain function during subjective self-appraisal in regions commonly affected by AD. Although these participants were asymptomatic and middle-aged, the findings suggest there may be subtle alterations in brain function attributable to AD risk factors. PMID:17909128

  19. Glucose Metabolism: A Sweet Relief of Alzheimer's Disease.

    PubMed

    Duran-Aniotz, Claudia; Hetz, Claudio

    2016-09-12

    Patients and individuals at risk for Alzheimer's disease show reduced glucose metabolism in the brain. A new study takes advantage of a fly model of Alzheimer's disease to demonstrate that enhancing glucose uptake in neurons has strong neuroprotective effects involving improved proteostasis. PMID:27623263

  20. Providing Counseling for Individuals with Alzheimer's Disease and Their Caregivers

    ERIC Educational Resources Information Center

    Granello, Paul F.; Fleming, Matthew S.

    2008-01-01

    Alzheimer's disease is a progressive condition that results in brain wasting and eventual death. With its increasing diagnosis rate, counselors will likely acquire clients with Alzheimer's disease or their caregivers. Important background information and several practical counseling methods are provided that may assist counselors working with this…

  1. Increased risk of type 2 diabetes in Alzheimer disease.

    PubMed

    Janson, Juliette; Laedtke, Thomas; Parisi, Joseph E; O'Brien, Peter; Petersen, Ronald C; Butler, Peter C

    2004-02-01

    Alzheimer disease and type 2 diabetes are characterized by increased prevalence with aging, a genetic predisposition, and comparable pathological features in the islet and brain (amyloid derived from amyloid beta protein in the brain in Alzheimer disease and islet amyloid derived from islet amyloid polypeptide in the pancreas in type 2 diabetes). Evidence is growing to link precursors of amyloid deposition in the brain and pancreas with the pathogenesis of Alzheimer disease and type 2 diabetes, respectively. Given these similarities, we questioned whether there may be a common underlying mechanism predisposing to islet and cerebral amyloid. To address this, we first examined the prevalence of type 2 diabetes in a community-based controlled study, the Mayo Clinic Alzheimer Disease Patient Registry (ADPR), which follows patients with Alzheimer disease versus control subjects without Alzheimer disease. In addition to this clinical study, we performed a pathological study of autopsy cases from this same community to determine whether there is an increased prevalence of islet amyloid in patients with Alzheimer disease and increased prevalence of cerebral amyloid in patients with type 2 diabetes. Patients who were enrolled in the ADPR (Alzheimer disease n = 100, non-Alzheimer disease control subjects n = 138) were classified according to fasting glucose concentration (FPG) as nondiabetic (FPG <110 mg/dl), impaired fasting glucose (IFG, FPG 110-125 mg/dl), and type 2 diabetes (FPG >126 mg/dl). The mean slope of FPG over 10 years in each case was also compared between Alzheimer disease and non-Alzheimer disease control subjects. Pancreas and brain were examined from autopsy specimens obtained from 105 humans (first, 28 cases of Alzheimer disease disease vs. 21 non-Alzheimer disease control subjects and, second, 35 subjects with type 2 diabetes vs. 21 non-type 2 diabetes control subjects) for the presence of islet and brain amyloid. Both type 2 diabetes (35% vs. 18%; P < 0

  2. Biomarkers for early detection of Alzheimer disease.

    PubMed

    Barber, Robert C

    2010-09-01

    The existence of an effective biomarker for early detection of Alzheimer disease would facilitate improved diagnosis and stimulate therapeutic trials. Multidisciplinary clinical diagnosis of Alzheimer disease is time consuming and expensive and relies on experts who are rarely available outside of specialty clinics. Thus, many patients do not receive proper diagnosis until the disease has progressed beyond stages in which treatments are maximally effective. In the clinical trial setting, rapid, cost-effective screening of patients for Alzheimer disease is of paramount importance for the development of new treatments. Neuroimaging of cortical amyloid burden and volumetric changes in the brain and assessment of protein concentrations (eg, β-amyloid 1-42, total tau, phosphorylated tau) in cerebrospinal fluid are diagnostic tools that are not widely available. Known genetic markers do not provide sufficient discriminatory power between different forms of dementia to be useful in isolation. Recent studies using panels of biomarkers for diagnosis of Alzheimer disease or mild cognitive impairment have been promising, though no such studies have been cross-validated in independent samples of subjects. The ideal biomarker enabling early detection of Alzheimer disease has not yet been identified.

  3. Neural stem cells and Alzheimer's disease: challenges and hope.

    PubMed

    Zhongling Feng; Gang Zhao; Lei Yu

    2009-01-01

    Alzheimer's disease is characterized by degeneration and dysfunction of synapses and neurons in brain regions critical for learning and memory functions. The endogenous generation of new neurons in certain regions of the mature brain, derived from primitive cells termed neural stem cells, has raised hope that neural stem cells may be recruited for structural brain repair. Stem cell therapy has been suggested as a possible strategy for replacing damaged circuitry and restoring learning and memory abilities in patients with Alzheimer's disease. In this review, we outline the promising investigations that are raising hope, and understanding the challenges behind translating underlying stem cell biology into novel clinical therapeutic potential in Alzheimer's disease.

  4. Advancing frontiers in Alzheimer's disease research

    SciTech Connect

    Glenner, G.G.; Wurtman, R.J.

    1987-01-01

    This book contain 16 chapters. Some of the titles are: Transmitter Alterations in Alzheimer's Disease: Relation to Cortical Dysfunction as Suggested by Positron Emission Tomography; Single-Photon Emission Computed Tomography in the Clinical Evaluation of Dementia; Clinical Diagnosis of Alzheimer's Disease; Down's Syndrome and Alzheimer's Disease: What is the Relationship; and Beta Protein: A Possible Marker for Alzheimer's Disease.

  5. Chromatin structure in scrapie and Alzheimer's disease.

    PubMed

    McLachlan, D R; Lukiw, W J; Cho, H J; Carp, R I; Wisniewski, H

    1986-11-01

    Scrapie affected brains exhibit a number of pathological features in common with the human neurodegenerative condition, Alzheimer's disease. The present report describes studies on chromatin structure seen in these two disease processes. Chromatin associated proteins influence transcriptional activity of DNA through an effect upon chromatin structure. We examined chromatin structure by: measuring the capacity of the enzyme micrococcal nuclease to release mono- and dinucleosomes from isolated nuclei and measuring DNA-histone interactions by examining the effect of ambient tonicity upon the release of chromatin proteins. In two strains of mice infected with two strains of scrapie agent there was reduced accessibility to micrococcal nuclease and an increased content on dinucleosomes of the histone H1 and H1(0) types. These changes precede clinical signs of scrapie and resemble those found in the human conditions of Alzheimer's and Pick's disease. Scrapie mouse brain differs from Alzheimer brain in that scrapie does not alter histone-DNA interactions as monitored by ionically induced histone release from chromatin. Despite similarities, the scrapie agent appears to operate upon different molecular mechanisms than those found in Alzheimer's disease.

  6. Sequential relationships between grey matter and white matter atrophy and brain metabolic abnormalities in early Alzheimer's disease.

    PubMed

    Villain, Nicolas; Fouquet, Marine; Baron, Jean-Claude; Mézenge, Florence; Landeau, Brigitte; de La Sayette, Vincent; Viader, Fausto; Eustache, Francis; Desgranges, Béatrice; Chételat, Gaël

    2010-11-01

    Hippocampal atrophy, posterior cingulate and frontal glucose hypometabolism, and white-matter tract disruption are well described early macroscopic events in Alzheimer's disease. The relationships between these three types of alterations have been documented in previous studies, but their chronology still remains to be established. The present study used multi-modal fluorodeoxyglucose-positron emission tomography and magnetic resonance imaging longitudinal data to address this question in patients with amnestic mild cognitive impairment. We found unidirectional, specific sequential relationships between: (i) baseline hippocampal atrophy and both cingulum bundle (r = 0.70; P = 3 × 10⁻³) and uncinate fasciculus (r = 0.75; P = 7 × 10⁻⁴) rate of atrophy; (ii) baseline cingulum bundle atrophy and rate of decline of posterior (r = 0.72; P = 2 × 10⁻³); and anterior (r = 0.74; P = 1 × 10⁻³) cingulate metabolism; and (iii) baseline uncinate white matter atrophy and subgenual metabolism rate of change (r = 0.65; P = 6 × 10⁻³). Baseline local grey matter atrophy was not found to contribute to hypometabolism progression within the posterior and anterior cingulate as well as subgenual cortices. These findings suggest that hippocampal atrophy progressively leads to disruption of the cingulum bundle and uncinate fasciculus, which in turn leads to glucose hypometabolism of the cingulate and subgenual cortices, respectively. This study reinforces the relevance of remote mechanisms above local interactions to account for the pattern of metabolic brain alteration observed in amnestic mild cognitive impairment, and provides new avenues to assess the sequence of events in complex diseases characterized by multiple manifestations.

  7. Integrative Understanding of Emergent Brain Properties, Quantum Brain Hypotheses, and Connectome Alterations in Dementia are Key Challenges to Conquer Alzheimer's Disease

    PubMed Central

    Kuljiš, Rodrigo O.

    2010-01-01

    The biological substrate for cognition remains a challenge as much as defining this function of living beings. Here, we examine some of the difficulties to understand normal and disordered cognition in humans. We use aspects of Alzheimer's disease and related disorders to illustrate how the wealth of information at many conceptually separate, even intellectually decoupled, physical scales – in particular at the Molecular Neuroscience versus Systems Neuroscience/Neuropsychology levels – presents a challenge in terms of true interdisciplinary integration towards a coherent understanding. These unresolved dilemmas include critically the as yet untested quantum brain hypothesis, and the embryonic attempts to develop and define the so-called connectome in humans and in non-human models of disease. To mitigate these challenges, we propose a scheme incorporating the vast array of scales of the space and time (space–time) manifold from at least the subatomic through cognitive-behavioral dimensions of inquiry, to achieve a new understanding of both normal and disordered cognition, that is essential for a new era of progress in the Generative Sciences and its application to translational efforts for disease prevention and treatment. PMID:21188254

  8. Plasma tau as a window to the brain-negative associations with brain volume and memory function in mild cognitive impairment and early Alzheimer's disease.

    PubMed

    Chiu, Ming-Jang; Chen, Ya-Fang; Chen, Ta-Fu; Yang, Shieh-Yueh; Yang, Fan-Pei Gloria; Tseng, Tien-Wen; Chieh, Jen-Jie; Chen, Jia-Chun Rare; Tzen, Kai-Yuan; Hua, Mau-Sun; Horng, Herng-Er

    2014-07-01

    Neurofibrillary tangles are associated with cognitive dysfunction, and hippocampal atrophy with increased CSF tau markers. However, the plasma tau levels of Alzheimer's disease (AD) have not been well studied. We investigated plasma tau by using an immunomagnetic reduction assay in 20 patients with mild cognitive impairment (MCI) due to AD, 10 early AD dementia, and 30 healthy elders (HE). All received a 3D-brain MRI scan and a set of cognitive function test. We explored their relationships with both brain structure and cognitive functions. Images were analyzed to determine the brain volumes and gray matter densities. Patients with MCI or early AD had significantly increased plasma tau levels compared with HE. Plasma tau levels were negatively associated with the performance of logical memory, visual reproduction, and verbal fluency; also negatively associated with volume of total gray matter, hippocampus, amygdala; and gray matter densities of various regions. Regression analyses indicated that logical memory explained 0.394 and hippocampus volume predicted .608 of the variance of plasma tau levels, both P < 0.001. Education years were negatively associated with the gray matter densities of the supramarginal (r = -0.407), middle temporal gyrus (r = -0.40) and precuneus (r = -0.377; all P < 0.05) in HE; and negatively associated with plasma tau levels in patients (r = -0.626). We propose that plasma tau may serve as a window to both structure and function of the brain. Higher education is a protective factor against AD and is associated with lower plasma tau levels in patients. PMID:24129926

  9. Biomarker Modeling of Alzheimer's Disease

    PubMed Central

    Jack, Clifford R; Holtzman, David M

    2014-01-01

    Alzheimer's disease (AD) is a slowly progressing disorder in which pathophysiological abnormalities, detectable in vivo by biomarkers, precede overt clinical symptoms by many years to decades. Five AD biomarkers are sufficiently validated to have been incorporated into clinical diagnostic criteria and commonly used in therapeutic trials. Current AD biomarkers fall into 2 categories: biomarkers of amyloid-β plaques and of tau-related neurodegeneration. Three of the 5 are imaging measures and two are cerebrospinal fluid analytes. AD biomarkers do not evolve in an identical manner but rather in a sequential but temporally overlapping manner. Models of the temporal evolution of AD biomarkers can take the form of plots of biomarker severity (degree of abnormality) vs. time. In this review we discuss several time-dependent models of AD which take into consideration varying age of onset (early vs. late) and the influence of aging and co-occurring brain pathologies that commonly arise in the elderly. PMID:24360540

  10. [Alzheimer's disease: the infectious hypothesis].

    PubMed

    Roubaud Baudron, Claire; Varon, Christine; Mégraud, Francis; Salles, Nathalie

    2015-12-01

    Several hypotheses are proposed for understanding the Alzheimer's disease (AD) pathological mechanisms, mainly the amyloid theory, but the process inducing Aß peptide deposit, tau protein degeneration, and ultimately neuronal loss, is still to be elucidated. Alteration of the blood-brain barrier and activation of neuroinflammation seem to play an important role in AD neurodegeneration, especially in the decrease of Aß peptide clearance, therefore suggesting a role of infectious agents. Epidemiological and experimental studies on cellular or murine models related to herpes simplex virus (HSV), spirochetes, Chlamydia pneumoniae or Borrelia, and systemic inflammation are reviewed. Aß peptide or tau protein could also behave like a prion protein. Infectious agents could thus have an impact on AD by direct interaction with neurotropism or systemic inflammation. Although the results of these studies are not conclusive, they may contribute to the understanding of AD pathology. PMID:26707559

  11. Communication of brain network core connections altered in behavioral variant frontotemporal dementia but possibly preserved in early-onset Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Daianu, Madelaine; Jahanshad, Neda; Mendez, Mario F.; Bartzokis, George; Jimenez, Elvira E.; Thompson, Paul M.

    2015-03-01

    Diffusion imaging and brain connectivity analyses can assess white matter deterioration in the brain, revealing the underlying patterns of how brain structure declines. Fiber tractography methods can infer neural pathways and connectivity patterns, yielding sensitive mathematical metrics of network integrity. Here, we analyzed 1.5-Tesla wholebrain diffusion-weighted images from 64 participants - 15 patients with behavioral variant frontotemporal dementia (bvFTD), 19 with early-onset Alzheimer's disease (EOAD), and 30 healthy elderly controls. Using whole-brain tractography, we reconstructed structural brain connectivity networks to map connections between cortical regions. We evaluated the brain's networks focusing on the most highly central and connected regions, also known as hubs, in each diagnostic group - specifically the "high-cost" structural backbone used in global and regional communication. The high-cost backbone of the brain, predicted by fiber density and minimally short pathways between brain regions, accounted for 81-92% of the overall brain communication metric in all diagnostic groups. Furthermore, we found that the set of pathways interconnecting high-cost and high-capacity regions of the brain's communication network are globally and regionally altered in bvFTD, compared to healthy participants; however, the overall organization of the high-cost and high-capacity networks were relatively preserved in EOAD participants, relative to controls. Disruption of the major central hubs that transfer information between brain regions may impair neural communication and functional integrity in characteristic ways typical of each subtype of dementia.

  12. Computation of brain neurodegeneration in the Alzheimer's fly

    NASA Astrophysics Data System (ADS)

    Lee, P. C.; Huang, Y. R.; Chang, H. M.; Chiang, A. S.; Ching, Y. T.

    2006-03-01

    Expression of human Aβ42 peptide in the Drosophila brain induces pathological phenotypes resembling Alzheimer's disease (PNAS 101, 6623-6628). Three-dimensional confocal imaging reveals extensive vacuoles caused by neurodegeneration in the brain of aged but not young Aβ42 flies. Here, we report a three-dimensional computation algorism allowing semi-automatic measurement of numbers and volumes of brain vacuoles. The method employed matched filters, α-shape, and the active-contour techniques. Using this method, a good result depicting the contours of the vacuoles can be obtained. A more accurate algorithm is still under development. Accurate evaluation of brain pathology in Alzheimer's flies may facilitate the understanding of molecular mechanisms underlying Aβ toxicity and the discovery of novel therapeutic targets for Alzheimer's disease.

  13. Computational approaches to the prediction of blood-brain barrier permeability: A comparative analysis of central nervous system drugs versus secretase inhibitors for Alzheimer's disease.

    PubMed

    Rishton, Gilbert M; LaBonte, Kristen; Williams, Antony J; Kassam, Karim; Kolovanov, Eduard

    2006-05-01

    This review summarizes progress made in the development of fully computational approaches to the prediction of blood-brain barrier (BBB) permeability of small molecules, with a focus on rapid computational methods suitable for the analysis of large compound sets and virtual screening. A comparative analysis using the recently developed Advanced Chemistry Development (ACD/Labs) Inc BBB permeability algorithm for the calculation of logBB values for known Alzheimer's disease medicines, selected central nervous system drugs and new secretase inhibitors for Alzheimer's disease, is presented. The trends in logBB values and the associated physiochemical properties of these agents as they relate to the potential for BBB permeability are also discussed. PMID:16729726

  14. Alzheimer disease: Quantitative analysis of I-123-iodoamphetamine SPECT brain imaging

    SciTech Connect

    Hellman, R.S.; Tikofsky, R.S.; Collier, B.D.; Hoffmann, R.G.; Palmer, D.W.; Glatt, S.L.; Antuono, P.G.; Isitman, A.T.; Papke, R.A.

    1989-07-01

    To enable a more quantitative diagnosis of senile dementia of the Alzheimer type (SDAT), the authors developed and tested a semiautomated method to define regions of interest (ROIs) to be used in quantitating results from single photon emission computed tomography (SPECT) of regional cerebral blood flow performed with N-isopropyl iodine-123-iodoamphetamine. SPECT/IMP imaging was performed in ten patients with probable SDAT and seven healthy subjects. Multiple ROIs were manually and semiautomatically generated, and uptake was quantitated for each ROI. Mean cortical activity was estimated as the average of the mean activity in 24 semiautomatically generated ROIs; mean cerebellar activity was determined from the mean activity in separate ROIs. A ratio of parietal to cerebellar activity less than 0.60 and a ratio of parietal to mean cortical activity less than 0.90 allowed correct categorization of nine of ten and eight of ten patients, respectively, with SDAT and all control subjects. The degree of diminished mental status observed in patients with SDAT correlated with both global and regional changes in IMP uptake.

  15. Alzheimer's disease susceptibility genes APOE and TOMM40, and brain white matter integrity in the Lothian Birth Cohort 1936.

    PubMed

    Lyall, Donald M; Harris, Sarah E; Bastin, Mark E; Muñoz Maniega, Susana; Murray, Catherine; Lutz, Michael W; Saunders, Ann M; Roses, Allen D; Valdés Hernández, Maria del C; Royle, Natalie A; Starr, John M; Porteous, David J; Wardlaw, Joanna M; Deary, Ian J

    2014-06-01

    Apolipoprotein E (APOE) ε genotype has previously been significantly associated with cognitive, brain imaging, and Alzheimer's disease-related phenotypes (e.g., age of onset). In the TOMM40 gene, the rs10524523 ("523") variable length poly-T repeat polymorphism has more recently been associated with similar ph/enotypes, although the allelic directions of these associations have varied between initial reports. Using diffusion magnetic resonance imaging tractography, the present study aimed to investigate whether there are independent effects of apolipoprotein E (APOE) and TOMM40 genotypes on human brain white matter integrity in a community-dwelling sample of older adults, the Lothian Birth Cohort 1936 (mean age = 72.70 years, standard deviation = 0.74, N approximately = 640-650; for most analyses). Some nominally significant effects were observed (i.e., covariate-adjusted differences between genotype groups at p < 0.05). For APOE, deleterious effects of ε4 "risk" allele presence (vs. absence) were found in the right ventral cingulum and left inferior longitudinal fasciculus. To test for biologically independent effects of the TOMM40 523 repeat, participants were stratified into APOE genotype subgroups, so that any significant effects could not be attributed to APOE variation. In participants with the APOE ε3/ε4 genotype, effects of TOMM40 523 status were found in the left uncinate fasciculus, left rostral cingulum, left ventral cingulum, and a general factor of white matter integrity. In all 4 of these tractography measures, carriers of the TOMM40 523 "short" allele showed lower white matter integrity when compared with carriers of the "long" and "very-long" alleles. Most of these effects survived correction for childhood intelligence test scores and vascular disease history, though only the effect of TOMM40 523 on the left ventral cingulum integrity survived correction for false discovery rate. The effects of APOE in this older population are more specific and

  16. Personality changes in Alzheimer's disease.

    PubMed

    Chatterjee, A; Strauss, M E; Smyth, K A; Whitehouse, P J

    1992-05-01

    How personality changes in Alzheimer's disease is not well understood. Accentuations of premorbid personality, systematic shifts in personality traits, and specific personality changes affecting subtypes of patients have been postulated. To investigate which of these alternatives occurs in Alzheimer's disease, caregivers were given a comprehensive personality inventory standardized for use by informants. Caregivers observed more neurotic, less extroverted, and less conscientious behavior. To a smaller extent, patients with Alzheimer's disease were reported as becoming less agreeable and less open. The changes in reports of neuroticism, extroversion, agreeableness, and openness suggested consistent systematic shifts across all patients. Patients with depressive features were reported to have been more neurotic; those with paranoid delusions were reported as having been more hostile. Premorbid personality traits may predispose to subsequent psychiatric symptoms in Alzheimer's disease.

  17. Redox proteomics analysis of HNE-modified proteins in Down syndrome brain: clues for understanding the development of Alzheimer disease.

    PubMed

    Di Domenico, Fabio; Pupo, Gilda; Tramutola, Antonella; Giorgi, Alessandra; Schininà, Maria Eugenia; Coccia, Raffaella; Head, Elizabeth; Butterfield, D Allan; Perluigi, Marzia

    2014-06-01

    Down syndrome (DS) is the most common genetic cause of intellectual disability, due to partial or complete triplication of chromosome 21. DS subjects are characterized by a number of abnormalities including premature aging and development of Alzheimer disease (AD) neuropathology after approximately 40 years of age. Several studies show that oxidative stress plays a crucial role in the development of neurodegeneration in the DS population. Increased lipid peroxidation is one of the main events causing redox imbalance within cells through the formation of toxic aldehydes that easily react with DNA, lipids, and proteins. In this study we used a redox proteomics approach to identify specific targets of 4-hydroxynonenal modifications in the frontal cortex from DS cases with and without AD pathology. We suggest that a group of identified proteins followed a specific pattern of oxidation in DS vs young controls, probably indicating characteristic features of the DS phenotype; a second group of identified proteins showed increased oxidation in DS/AD vs DS, thus possibly playing a role in the development of AD. The third group of comparison, DS/AD vs old controls, identified proteins that may be considered specific markers of AD pathology. All the identified proteins are involved in important biological functions including intracellular quality control systems, cytoskeleton network, energy metabolism, and antioxidant response. Our results demonstrate that oxidative damage is an early event in DS, as well as dysfunctions of protein-degradation systems and cellular protective pathways, suggesting that DS subjects are more vulnerable to oxidative damage accumulation that might contribute to AD development. Further, considering that the majority of proteins have been already demonstrated to be oxidized in AD brain, our results strongly support similarities with AD in DS.

  18. Quiz: Alzheimer's Disease Quiz | Alzheimer's disease | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Alzheimer's Disease Quiz: Alzheimer's Disease Quiz Past Issues / Fall 2010 Table of ... How many people in the United States have Alzheimer's disease? as many as 5.1 million as ...

  19. The immune system, amyloid-beta peptide, and Alzheimer's disease.

    PubMed

    Weksler, Marc E; Gouras, Gunnar; Relkin, Norman R; Szabo, Paul

    2005-06-01

    In this review, the case is made that amyloid-beta peptide in the brain of patients with Alzheimer's disease is a primary cause of the disease and that immunotherapy directed against this peptide has the potential to halt and/or reverse disease progression. This supposition is supported by the capacity of anti-beta-amyloid peptide antibodies to prevent or reverse the disease in mouse models of Alzheimer's disease. Furthermore, preliminary results obtained in a small number of patients with Alzheimer's disease are consistent with the observations made in the mouse model of this disease. We review the relationship between the immune system, amyloid-beta peptide, and Alzheimer's disease and the progress made in applying immunotherapy to patients with Alzheimer's disease.

  20. Cognitive intervention in Alzheimer disease.

    PubMed

    Buschert, Verena; Bokde, Arun L W; Hampel, Harald

    2010-09-01

    Alzheimer disease (AD) is one of the most prevalent chronic medical conditions affecting the elderly population. The effectiveness of approved antidementia drugs, however, is limited-licensed AD medications provide only moderate relief of clinical symptoms. Cognitive intervention is a noninvasive therapy that could aid prevention and treatment of AD. Data suggest that specifically designed cognitive interventions could impart therapeutic benefits to patients with AD that are associated with substantial biological changes within the brain. Moreover, evidence indicates that a combination of pharmacological and non-pharmacological interventions could provide greater relief of clinical symptoms than either intervention given alone. Functional and structural MRI studies have increased our understanding of the underlying neurobiological mechanisms of aging and neurodegeneration, but the use of neuroimaging to investigate the effect of cognitive intervention on the brain remains largely unexplored. This Review provides an overview of the use of cognitive intervention in the healthy elderly population and patients with AD, and summarizes emerging findings that provide evidence for the effectiveness of this approach. Finally, we present recommendations for future research on the use of cognitive interventions in AD and discuss potential effects of this therapy on disease modification.

  1. 2011 CCNP Heinz Lehman Award paper: Searching for an endogenous anti-Alzheimer molecule: identifying small molecules in the brain that slow Alzheimer disease progression by inhibition of β-amyloid aggregation

    PubMed Central

    Meek, Autumn R.; Simms, Gordon A.; Weaver, Donald F.

    2013-01-01

    Background Alzheimer disease is a neurodegenerative disorder that progresses with marked interindividual clinical variability. We postulate the existence of endogenous molecules within the human brain exerting an antiaggregant activity that will prevent/slow Alzheimer disease progression. Methods We performed in silico studies to determine if the small endogenous molecules L-phosphoserine (L-PS) and 3-hydroxyanthranilic acid (3-HAA) could bind to the target region of β-amyloid responsible for protein misfolding. In vitro assays measured the antiaggregation effect of these molecules at varying concentrations. Results In silico studies demonstrated that L-PS and 3-HAA, both endogenous brain molecules, were capable of binding to the histidine13–histidine–glutamine–lysine16 (HHQK) region of β-amyloid involved in misfolding: these interactions were energetically favoured. The in vitro assays showed that both L-PS and 3-HAA were capable of inhibiting β-amyloid aggregation in a dose-dependent manner, with 3-HAA being more potent than L-PS. Limitations Studies were performed in silico and in vitro but not in vivo. Conclusion We successfully identified 2 endogenous brain molecules, L-PS and 3-HAA, that were capable of binding to the region of β-amyloid that leads to protein misfolding and neurotoxicity. Both L-PS and 3-HAA were able to inhibit β-amyloid aggregation in varying concentrations; levels of these compounds in the brain may impact their effectiveness in slowing/preventing β-amyloid aggregation. PMID:23394811

  2. Relationship of aluminum to Alzheimer's disease.

    PubMed

    Perl, D P

    1985-11-01

    Alzheimer's disease is a progressive degenerative brain disease of unknown etiology, characterized by the development of large numbers of neurofibrillary tangles and senile plaques in the brain. Aluminum salts may be used experimentally to produce lesions which are similar, but not identical, to the neurofibrillary tangle. Although some studies have reported increased amounts of aluminum in the brains of Alzheimer's disease victims, these bulk analysis studies have been difficult to replicate and remain controversial. Using scanning electron microscopy with X-ray spectrometry, we have investigated this question on the cellular level. We have identified abnormal accumulations of aluminum within neurons derived from Alzheimer's disease patients containing neurofibrillary tangles. Similar accumulations have been detected in the numerous neurofibrillary tangle-bearing neurons seen in the brains of the indigenous native population of the island of Guam who suffer from amyotrophic lateral sclerosis and parkinsonism with dementia. Epidemiologic evidence strongly suggests a causal role for local environmental conditions relating to availability of aluminum, calcium, and magnesium. In view of the fact that a major consequence of acid rain is the liberation of large amounts of aluminum in bioavailable forms, concerns are raised about possible human health risks of this environmental phenomenon.

  3. Structural networks in Alzheimer's disease.

    PubMed

    Reid, Andrew T; Evans, Alan C

    2013-01-01

    Alzheimer's disease (AD) appears to be a uniquely human condition, which is possibly attributable to our expanded longevity and peculiar capacity for episodic memory. Due to a lack of naturally-occurring animal model for investigating AD pathogenesis, our knowledge about the disease must be derived from correlational observation of humans, or from animal models produced by genetic manipulation of known risk factors in humans. Advances in neuroimaging, cellular and molecular science, and computational methods have proven useful for the improvement of such techniques, but the general limitation persists; as a result we remain without clear answers to some of the fundamental questions posed by AD. On the other hand, much progress has been made in characterizing the longitudinal progression of AD pathology, which includes the formation of "plaques and tangles", a distinct topological pattern of atrophy of grey and white matter, and the concurrent decline of specific cognitive functions, beginning with mild memory impairments and ending with general debilitating dementia. In this review, we first discuss the existing literature which characterizes AD etiology, pathology, and pathogenesis, with the intention of framing the disease as primarily a "disconnection syndrome". We next describe methodologies for investigating the topological properties of human brain networks, using graph theoretical techniques and connectivity information derived from anatomical and diffusion-weighted MR imaging. Finally, we discuss how these methodologies have been applied to systems-level analyses of AD, to help characterize the network changes underlying the disease process, and how these patterns relate to specific cognitive outcome measures. PMID:23294972

  4. A comparative evaluation of treatments with 17β-estradiol and its brain-selective prodrug in a double-transgenic mouse model of Alzheimer's disease.

    PubMed

    Tschiffely, Anna E; Schuh, Rosemary A; Prokai-Tatrai, Katalin; Prokai, Laszlo; Ottinger, Mary Ann

    2016-07-01

    Estrogens are neuroprotective and, thus, potentially useful for the therapy of Alzheimer's disease; however, clinical use of hormone therapy remains controversial due to adverse peripheral effects. The goal of this study was to investigate the benefits of treatment with 10β,17β-dihydroxyestra-1,4-dien-3-one (DHED), a brain-selective prodrug of 17β-estradiol, in comparison with the parent hormone using APPswe/PS1dE9 double transgenic mice to model the pathology of the disease. Ovariectomized and intact females were continuously treated with vehicle, 17β-estradiol, or DHED via subcutaneous osmotic pumps from 6 to 8months of age. We confirmed that this prolonged treatment with DHED did not stimulate uterine tissue, whereas 17β-estradiol treatment increased uterine weight. Amyloid precursor protein decreased in both treatment groups of intact, but not in ovariectomized double transgenic females in which ovariectomy already decreased the expression of this protein significantly. However, reduced brain amyloid-β peptide levels could be observed for both treatments. Consequently, double-transgenic ovariectomized and intact mice had higher cognitive performance compared to untreated control animals in response to both estradiol and DHED administrations. Overall, the tested brain-selective 17β-estradiol prodrug proved to be an effective early-stage intervention in an Alzheimer's disease-relevant mouse model without showing systemic impact and, thus, warrants further evaluation as a potential therapeutic candidate.

  5. Mass spectrometric identification of citrullination sites and immunohistochemical detection of citrullinated glial fibrillary acidic protein in Alzheimer's disease brains.

    PubMed

    Ishigami, Akihito; Masutomi, Hirofumi; Handa, Setsuko; Nakamura, Megumi; Nakaya, Shuuichi; Uchida, Yoshiaki; Saito, Yuko; Murayama, Shigeo; Jang, Byungki; Jeon, Yong-Chul; Choi, Eun-Kyoung; Kim, Yong-Sun; Kasahara, Yasushi; Maruyama, Naoki; Toda, Tosifusa

    2015-11-01

    Peptidylarginine deiminases (PADs) are posttranslational modification enzymes that convert protein arginine to citrulline residues in a calcium ion-dependent manner. Previously, we reported the abnormal accumulation of citrullinated proteins and the increase in the amount of PAD2 in hippocampi from Alzheimer's disease (AD) patients. Moreover, glial fibrillary acidic protein (GFAP), an astrocyte-specific marker protein, and vimentin were identified as citrullinated proteins by using two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. To clarify the substrate specificity of PADs against GFAP, we prepared recombinant human (rh)PAD1, rhPAD2, rhPAD3, rhPAD4, and rhGFAP. After incubation of rhGFAP with rhPAD1, rhPAD2, rhPAD3, and rhPAD4, citrullinated (cit-)rhGFAP was detected by Western blotting. The citrullination of rhGFAP by rhPAD2 was unique, specific, and time dependent; additionally, rhPAD1 slightly citrullinated rhGFAP. We then generated eight anti-cit-rhGFAP monoclonal antibodies, CTGF-125, -128, -129, -1212, -1213, -1221, -122R, and -1224R, which reacted specifically with cit-rhGFAP. Two of those eight monoclonal antibodies, CTGF-122R and -1224R, reacted with both cit-rhGFAP and rhGFAP in Western blots. By using the CTGF-1221 antibody and a tandem mass spectrometer, we identified the two independent citrullination sites (R270Cit and R416Cit) of cit-rhGFAP. Immunohistochemical analysis with CTGF-1221 antibody revealed cit-GFAP staining in the hippocampus of AD brain, and the cit-GFAP-positive cells appeared to be astrocyte-like cells. These collective results strongly suggest that PAD2 is responsible for the citrullination of GFAP in the progression of AD and that the monoclonal antibody CTGF-1221, reacting with cit-GFAP at R270Cit and R416Cit, is useful for immunohistochemical investigation of AD brains.

  6. [Late-onset Neurodegenerative Diseases Following Traumatic Brain Injury: Chronic Traumatic Encephalopathy (CTE) and Alzheimer's Disease Secondary to TBI (AD-TBI)].

    PubMed

    Takahata, Keisuke; Tabuchi, Hajime; Mimura, Masaru

    2016-07-01

    Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease, which is associated with mild repetitive traumatic brain injury (TBI). This long-term and progressive symptom due to TBI was initially called punch-drunk syndrome or dementia pugilistica, since it was believed to be associated with boxing. However, serial neuropathological studies of mild repetitive TBI in the last decade have revealed that CTE occurs not only in boxers but also in a wider population including American football players, wrestlers, and military personnel. CTE has gained large public interest owing to dramatic cases involving retired professional athletes wherein serious behavioral problems and tragic incidents were reported. Unlike mild repetitive TBI, a single episode of severe TBI can cause another type of late-onset neuropsychiatric disease including Alzheimer's disease (AD). Several epidemiological studies have shown that a single episode of severe TBI is one of the major risk factors of AD. Pathologically, both AD and CTE are characterized by abnormal accumulations of hyperphosphorylated tau proteins. However, recent neuropathological studies revealed that CTE demonstrates a unique pattern of tau pathology in neurons and astrocytes, and accumulation of other misfolded proteins such as TDP-43. Currently, no reliable biomarkers of late-onset neurodegenerative diseases following TBI are available, and a definitive diagnosis can be made only via postmortem neuropathological examination. Development in neuroimaging techniques such as tau and amyloid positron emission tomography imaging might not only enable early diagnosis of CTE, but also contribute to the interventions for prevention of late-onset neurodegenerative diseases following TBI. Further studies are necessary to elucidate the mechanisms of neurodegeneration in the living brain of patients with TBI. PMID:27395469

  7. Cadmium concentrations in the brains of Alzheimer cases

    SciTech Connect

    Spyrou, N.M.; Stedman, J.D.

    1996-12-31

    There is ongoing research in relating the concentration of elements in the brain with Alzheimer`s disease. The presence of particular elements, such as aluminum and vanadium, has been considered as a possible environmental factor, creating significant interest and controversy in the field. We have been analyzing brain tissue from the MRC Alzheimer`s Disease Brain Bank, Institute of Psychiatry, from a number of cortical regions of the brain, namely, the frontal, occipital, parietal, and temporal lobes, as well as from the left and right hemispheres of the same brain whenever possible. The techniques employed have been proton-induced X-ray emission (PIXE) analysis, proton-induced gamma-ray emission (PIGE) analysis, Rutherford backscattering (RBS), and instrumental neutron activation analysis. Neutron irradiations were carried out at the Imperial College Consort II reactor, whereas for PIXE, PIGE, and RBS, the University of Surrey Accelerator Laboratories were used employing a Van de Graaff accelerator. In this paper, we present the cadmium results from the frontal lobe of Alzheimer cases and controls determined by PIXE analysis.

  8. Brain imaging of mild cognitive impairment and Alzheimer's disease☆

    PubMed Central

    Yin, Changhao; Li, Siou; Zhao, Weina; Feng, Jiachun

    2013-01-01

    The rapidly increasing prevalence of cognitive impairment and Alzheimer's disease has the potential to create a major worldwide healthcare crisis. Structural MRI studies in patients with Alzheimer's disease and mild cognitive impairment are currently attracting considerable interest. It is extremely important to study early structural and metabolic changes, such as those in the hippocampus, entorhinal cortex, and gray matter structures in the medial temporal lobe, to allow the early detection of mild cognitive impairment and Alzheimer's disease. The microstructural integrity of white matter can be studied with diffusion tensor imaging. Increased mean diffusivity and decreased fractional anisotropy are found in subjects with white matter damage. Functional imaging studies with positron emission tomography tracer compounds enable detection of amyloid plaques in the living brain in patients with Alzheimer's disease. In this review, we will focus on key findings from brain imaging studies in mild cognitive impairment and Alzheimer's disease, including structural brain changes studied with MRI and white matter changes seen with diffusion tensor imaging, and other specific imaging methodologies will also be discussed. PMID:25206685

  9. The biological substrates of Alzheimer's disease

    SciTech Connect

    Scheibel, A.B.; Wechsler, A.F.; Brazier, M.A.B.

    1986-01-01

    This book contains 21 selections. Some of the titles are: Dementia of the Alzheimer Type: Genetic Aspects; Determination of Cerebral Metabolic Patterns in Dementia Using Positron Emission Tomography; Pathology of the Basal Forebrain in Alzheimer's Disease and Other Dementias; Characterization of Neurofibrillary Tangles with Monoclonal Antibodies Raised Against Alzheimer Neurofibrillary Tangles; and HLA Associations in Alzheimer's Disease.

  10. Brain imaging and blood biomarker abnormalities in children with autosomal-dominant Alzheimer's disease: A cross-sectional Study

    PubMed Central

    Quiroz, Y.T.; Schultz, A.; Chen, K.; Protas, H.; Brickhouse, M.; Fleisher, A.S.; Langbaum, J.B.; Thiyyagura, P.; Fagan, A.M.; Shah, A.R.; Muniz, M.; Arboleda-Velasquez, JF; Munoz, C.; Garcia, G.; Acosta-Baena, N.; Giraldo, M.; Tirado, V.; Ramirez, D.; Tariot, PN; Dickerson, B.C.; Sperling, R.A.; Lopera, F.; Reiman, E.M.

    2015-01-01

    IMPORTANCE Brain imaging and fluid biomarkers are characterized in children at risk for autosomal dominant Alzheimer disease (ADAD). OBJECTIVE To characterize and compare structural magnetic resonance imaging (MRI), resting-state and task-dependent functional MRI, and plasma amyloid-β (Aβ) measurements in presenilin 1 (PSEN1) E280A mutation–carrying and noncarrying children with ADAD. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional measures of structural and functional MRI and plasma Aβ assays were assessed in 18 PSEN1 E280A carriers and 19 noncarriers aged 9 to 17 years from a Colombian kindred with ADAD. Recruitment and data collection for this study were conducted at the University of Antioquia and the Hospital Pablo Tobon Uribe in Medellin, Colombia, between August 2011 and June 2012. MAIN OUTCOMES AND MEASURES All participants had blood sampling, structural MRI, and functional MRI during associative memory encoding and resting-state and cognitive assessments. Outcome measures included plasma Aβ1-42 concentrations and Aβ1-42:Aβ1-40 ratios, memory encoding–dependent activation changes, resting-state connectivity, and regional gray matter volumes. Structural and functional MRI data were compared using automated brain mapping algorithms and search regions related to AD. RESULTS Similar to findings in adult mutation carriers, in the later preclinical and clinical stages of ADAD, mutation-carrying children were distinguished from control individuals by significantly higher plasma Aβ1-42 levels (mean [SD]: carriers, 18.8 [5.1] pg/mL and noncarriers, 13.1 [3.2] pg/mL; P < .001) and Aβ1-42:Aβ1-40 ratios (mean [SD]: carriers, 0.32 [0.06] and noncarriers, 0.21 [0.03]; P < .001), as well as less memory encoding task–related deactivation in parietal regions (eg, mean [SD] parameter estimates for the right precuneus were −0.590 [0.50] for noncarriers and −0.087 [0.38] for carriers; P < .005 uncorrected). Unlike carriers in the later stages, mutation

  11. FDG-PET mapping the brain substrates of visuo-constructive processing in Alzheimer's disease.

    PubMed

    Förster, Stefan; Teipel, Stefan; Zach, Christian; Rominger, Axel; Cumming, Paul; Fougere, Christian la; Yakushev, Igor; Haslbeck, Marianne; Hampel, Harald; Bartenstein, Peter; Bürger, Katharina

    2010-05-01

    The anatomical basis of visuo-constructive impairment in AD is widely unexplored. FDG-PET can be used to determine functional neuronal networks underlying specific cognitive performance in the human brain. In the present study, we determined the pattern of cortical metabolism that was associated with visuo-constructive performance in AD. We employed two widely used visuo-constructive tests that differ in their demand on visual perception and processing capacity. Resting state FDG-PET scans were obtained in 29 probable AD patients, and cognitive tests were administered. We made a voxel-based regression analysis of FDG uptake to scores in visual test performance, using the SPM5 software. Performance in the CERAD Drawing test correlated with FDG uptake in the bilateral inferior temporal gyri, bilateral precuneus, right cuneus, right supramarginal gyrus and right middle temporal gyrus covering areas of dorsal and ventral visual streams. In contrast, performance in the more complex RBANS Figure Copy test correlated with FDG uptake in the bilateral fusiform gyri, right inferior temporal gyrus, left anterior cingulate gyrus, left parahippocampal gyrus, right middle temporal gyrus and right insula, encompassing the ventral visual stream and areas of higher-level visual processing. The study revealed neuronal networks underlying impaired visual test performance in AD. The extent of involvement of visual and higher order association cortex increased with greater test complexity. From a clinical point of view, both of these widely used visual tests evaluate the integrity of complementary cortical networks and may contribute complementary information on the integrity of visual processing in AD. PMID:19875130

  12. [Music therapy and Alzheimer disease].

    PubMed

    Tromeur, Emilie

    2014-01-01

    Music therapy and Alzheimer's dementia. Dementia such as Alzheimer's leads to the deterioration of the patient's global capacities. The cognitive disorders associated with it are disabling and affect every area of the patient's life. Every therapy's session undertaken with and by patients can act as a mirror of the progress of their disease and help to feel better, as described in this article on music therapy. PMID:24908841

  13. [Music therapy and Alzheimer disease].

    PubMed

    Tromeur, Emilie

    2014-01-01

    Music therapy and Alzheimer's dementia. Dementia such as Alzheimer's leads to the deterioration of the patient's global capacities. The cognitive disorders associated with it are disabling and affect every area of the patient's life. Every therapy's session undertaken with and by patients can act as a mirror of the progress of their disease and help to feel better, as described in this article on music therapy.

  14. Multiple genetic imaging study of the association between cholesterol metabolism and brain functional alterations in individuals with risk factors for Alzheimer's disease

    PubMed Central

    Bai, Feng; Yuan, Yonggui; Shi, Yongmei; Zhang, Zhijun

    2016-01-01

    Alzheimer's disease (AD) is a clinically and genetically heterogeneous neurodegenerative disease. Genes involved in cholesterol metabolism may play a role in the pathological changes of AD. However, the imaging genetics-based endophenotypes derived from polymorphisms in multiple functionally related genes are unclear in individuals with risk factors for AD. Forty-three amnestic mild cognitive impairment (aMCI) subjects and 30 healthy controls underwent resting-state functional magnetic resonance imaging (fMRI) measurements of brain topological organization. Thirty-three previously suggested tagging single nucleotide polymorphisms (SNPs) from 12 candidate genes in the cholesterol metabolism pathway were further investigated. A cholesterol metabolism pathway gene-based imaging genetics approach was then utilized to investigate disease-related differences between the groups based on genotype-by-aMCI interactions. The cholesterol metabolism pathway genes exerted widespread effects on the cortico-subcortical-cerebellar spontaneous brain activity. Meanwhile, left lateralization of global brain connectivity was associated with cholesterol metabolism pathway genes. The APOE rs429358 variation significantly influenced the brain network characteristics, affecting the activation of nodes as well as the connectivity of edges in aMCI subjects. The cholesterol metabolism pathway gene-based imaging genetics approach may provide new opportunities to understand the mechanisms underlying AD and suggested that APOE rs429358 is a core genetic variation that is associated with disease-related differences in brain function. PMID:26985771

  15. [Alzheimer's disease and diabetes - the common pathogenesis].

    PubMed

    Halmos, Tamas; Suba, Ilona

    2016-03-01

    Epidemiological studies presented evidence that Alzheimer's disease and type 2 diabetes share common features in their pathophysiology and clinical patterns. Insulin resistance is a characteristic feature of both diseases. According to the pathomechanism, inflammatory, metabolic, and an atypical form based on the deficiency of zinc ions can be distinguished. Glucose metabolic disorders, related to Alzheimer's disease, are type 2 diabetes, and prediabetes/metabolic syndrome. Based on the common pathophysiological patterns of these two diseases, Alzheimer's disease is customary called type 3 diabetes. In the research on dementias, insulin resistance stands in the highlight for its documented harmful effects on cognitive function and causes dementia. Insulin-like growth factor also influences cognitive functions. Reduced input of this hormone into the brain may also cause dementia, however literary data are controversial. In Alzheimer's disease, deposition of amyloid ß in the brain, hyperphosphorylation of tau proteins and dysruption of neurofibrilles are characteristic. Amyloid ß is co-secreted in the ß-cells of the pancreas with insulin. Amyloid ß and hyperphosphorylated tau protein were detected in the Langerhans islets by autopsy. Amyloid deposits, found in the pancreas and brain presented similarities. As a consequence of hyperglycemia, glycation endproducts cause the development of amyloid plaques, dysruption of neurofibrilles, and activated microglia, all are typical to Alzheimer's disease. Continuous hyperglycemia leads to oxidative stress, which used to play significant role in the development of both diseases. Low-grade inflammation is also a significant pathophysiological factor in both disorders. The sources of inflammation are proinflammatorical adipocytokines, dysbacteriosis, metabolic endotoxaemia, caused by lipopolysaccharides, and high fat diet which also lead to insulin resistance. Based on recent data, microbial amyloid, the main product of

  16. Does ionizing radiation influence Alzheimer's disease risk?

    PubMed Central

    Begum, Nasrin; Wang, Bing; Mori, Masahiko; Vares, Guillaume

    2012-01-01

    Alzheimer's disease (AD) is a human neurodegenerative disease, and its global prevalence is predicted to increase dramatically in the following decades. There is mounting evidence describing the effects of ionizing radiation (IR) on the brain, suggesting that exposure to IR might ultimately favor the development of AD. Therefore better understanding the possible connections between exposure to IR and AD pathogenesis is of utmost importance. In this review, recent developments in the research on the biological and cognitive effects of IR in the brain will be explored. Because AD is largely an age-related pathology, the effects of IR on ageing will be investigated. PMID:22872779

  17. Disruption of Amyloid Plaques Integrity Affects the Soluble Oligomers Content from Alzheimer Disease Brains

    PubMed Central

    Moyano, Javier; Sanchez-Mico, María; Torres, Manuel; Davila, Jose Carlos; Vizuete, Marisa; Gutierrez, Antonia; Vitorica, Javier

    2014-01-01

    The implication of soluble Abeta in the Alzheimer’s disease (AD) pathology is currently accepted. In fact, the content of soluble extracellular Abeta species, such as monomeric and/or oligomeric Abeta, seems to correlate with the clinico-pathological dysfunction observed in AD patients. However, the nature (monomeric, dimeric or other oligomers), the relative abundance, and the origin (extra-/intraneuronal or plaque-associated), of these soluble species are actually under debate. In this work we have characterized the soluble (defined as soluble in Tris-buffered saline after ultracentrifugation) Abeta, obtained from hippocampal samples of Braak II, Braak III–IV and Braak V–VI patients. Although the content of both Abeta40 and Abeta42 peptides displayed significant increase with pathology progression, our results demonstrated the presence of low, pg/µg protein, amount of both peptides. This low content could explain the absence (or below detection limits) of soluble Abeta peptides detected by western blots or by immunoprecipitation-western blot analysis. These data were in clear contrast to those published recently by different groups. Aiming to explain the reasons that determine these substantial differences, we also investigated whether the initial homogenization could mobilize Abeta from plaques, using 12-month-old PS1xAPP cortical samples. Our data demonstrated that manual homogenization (using Dounce) preserved the integrity of Abeta plaques whereas strong homogenization procedures (such as sonication) produced a vast redistribution of the Abeta species in all soluble and insoluble fractions. This artifact could explain the dissimilar and somehow controversial data between different groups analyzing human AD samples. PMID:25485545

  18. Alzheimer's Disease | NIH MedlinePlus the Magazine

    MedlinePlus

    ... of this page please turn JavaScript on. Feature: Alzheimer's Disease Living with Alzheimer's Disease Past Issues / Winter 2015 Table of Contents ... delay or prevent the disease. Free Guide for Alzheimer's Caregivers Caring for a person with Alzheimer's disease ...

  19. Alzheimer's Disease and the Eye☆

    PubMed Central

    Armstrong, Richard A.

    2010-01-01

    Dementia, including Alzheimer's disease (AD), is a major disorder causing visual problems in the elderly population. The pathology of AD includes the deposition in the brain of abnormal aggregates of β-amyloid (Aβ) in the form of senile plaques (SP) and abnormally phosphorylated tau in the form of neurofibrillary tangles (NFT). A variety of visual problems have been reported in patients with AD including loss of visual acuity (VA), colour vision and visual fields; changes in pupillary response to mydriatics, defects in fixation and in smooth and saccadic eye movements; changes in contrast sensitivity and in visual evoked potentials (VEP); and disturbances of complex visual functions such as reading, visuospatial function, and in the naming and identification of objects. Many of these changes are controversial with conflicting data in the literature and no ocular or visual feature can be regarded as particularly diagnostic of AD. In addition, some pathological changes have been observed to affect the eye, visual pathway, and visual cortex in AD. The optometrist has a role in helping a patient with AD, if it is believed that signs and symptoms of the disease are present, so as to optimize visual function and improve the quality of life.

  20. Regenerative medicine in Alzheimer's disease.

    PubMed

    Felsenstein, Kevin M; Candelario, Kate M; Steindler, Dennis A; Borchelt, David R

    2014-04-01

    Identifying novel, effective therapeutics for Alzheimer's disease (AD) is one of the major unmet medical needs for the coming decade. Because the current paradigm for developing and testing disease-modifying AD therapies is protracted and likely to be even longer, with the shift toward earlier intervention in preclinical AD, it is an open issue whether we can develop, test, and widely deploy a novel therapy in time to help the current at-risk generation if we continue to follow the standard paradigms of discovery and drug development. There is an imperative need to find safe and effective preventive measures that can be distributed rapidly to stem the coming wave of AD that will potentially engulf the next generation. We can define regenerative medicine broadly as approaches that use stem cell-based therapies or approaches that seek to modulate inherent neurogenesis. Neurogenesis, although most active during prenatal development, has been shown to continue in several small parts of the brain, including the hippocampus and the subventricular zone, suggesting its potential to reverse cognitive deficits. If AD pathology affects neurogenesis, then it follows that conditions that stimulate endogenous neurogenesis (eg, environmental stimuli, physical activity, trophic factors, cytokines, and drugs) may help to promote the regenerative and recovery process. Herein, we review the complex logistics of potentially implementing neurogenesis-based therapeutic strategies for the treatment of AD. PMID:24286919

  1. Regenerative Medicine in Alzheimer's Disease

    PubMed Central

    Felsenstein, Kevin M.; Candelario, Kate M.; Steindler, Dennis A.; Borchelt, David R.

    2013-01-01

    Identifying novel, effective therapeutics for Alzheimer's disease (AD) is one of the major unmet medical needs for the coming decade. Because the current paradigm for developing and testing disease modifying AD therapies is protracted and likely to be even longer with the shift towards earlier intervention in pre-clinical AD, it is an open question whether we can develop, test, and widely deploy a novel therapy in time to help the current at-risk generation if we continue to follow the standard paradigms of discovery and drug development. There is an imperative need to find safe and effective preventative measures that can be rapidly deployed to stem the coming wave of AD that will potentially engulf the next generation. We can broadly define regenerative medicine as approaches that use stem-cell-based therapies or approaches that seek to modulate inherent neurogenesis. Neurogenesis, though most active during pre-natal development has been shown to continue in several small parts of the brain, which includes the hippocampus and the subventricular zone, suggesting its potential to reverse cognitive deficits. If AD pathology impacts neurogenesis then it follows that conditions that stimulate endogenous neurogenesis (e.g., environmental stimuli, physical activity, trophic factors, cytokines, and drugs) may help to promote the regenerative and recovery process. Herein, we review the complex logistics of potentially implementing neurogenesis-based therapeutic strategies for the treatment of AD. PMID:24286919

  2. Pharmacogenomics in Alzheimer's disease.

    PubMed

    Cacabelos, Ramón

    2002-02-01

    Alzheimer's disease (AD) is a complex disorder associated with multiple genetic defects either mutational or of susceptibility. Information available on AD genetics does not explain in full the etiopathogenesis of AD, suggesting that environmental factors and/or epigenetic phenomena may also contribute to AD pathology and phenotypic expression of dementia. The genomics of AD is still in its infancy, but is helping to understand novel aspects of the disease including genetic epidemiology, multifactorial risk factors, pathogenic mechanisms associated with genetic networks and genetically-regulated metabolic cascades. AD genomics is also helping to develop new strategies in pharmacogenomic research and prevention. Functional genomics, proteomics, pharmacogenomics, high-throughput methods, combinatorial chemistry and modern bioinformatics will greatly contribute to accelerate drug development for AD and other complex disorders. Main genes involved in AD include mutational loci (APP, PS1, PS2, TAU) and multiple susceptibility loci (APOE, A2M, AACT, LRP1, IL1A, TNF, ACE, BACE, BCHE, CST3, MTHFR, GSK3B, NOS) distributed across the human genome. Genomic associations integrate bigenic, trigenic, tetragenic or polygenic matrix models to investigate the genomic organization of AD in comparison to the control population. Similar genetic models are used in pharmacogenomics to elucidate genotype-specific responses of AD patients to a particular drug or combination of drugs. Using APOE-related monogenic models it has been demonstrated that the therapeutic response to drugs in AD is genotype-specific. A multifactorial therapy combining 3 different drugs yielded positive results during the 6-12 months in approximately 60% of the patients. With this therapeutic strategy, APOE-4/4 carriers were the worst responders, and patients with the APOE-3/4 genotype were the best responders. In bigenic and trigenic models it was possible to differentiate the influencial effect of PS1 and PS2

  3. [Alzheimer's disease, supporting carers].

    PubMed

    Lottin, Arlette; Botter, René

    2016-03-01

    The association France Alzheimer provides carers with resources. It runs training programmes and organises "Memory Cafes". These initiatives give carers the opportunity to talk about their daily struggles, close to home, and to obtain advice on how to better manage their situation.

  4. Can Ketones Help Rescue Brain Fuel Supply in Later Life? Implications for Cognitive Health during Aging and the Treatment of Alzheimer's Disease.

    PubMed

    Cunnane, Stephen C; Courchesne-Loyer, Alexandre; Vandenberghe, Camille; St-Pierre, Valérie; Fortier, Mélanie; Hennebelle, Marie; Croteau, Etienne; Bocti, Christian; Fulop, Tamas; Castellano, Christian-Alexandre

    2016-01-01

    We propose that brain energy deficit is an important pre-symptomatic feature of Alzheimer's disease (AD) that requires closer attention in the development of AD therapeutics. Our rationale is fourfold: (i) Glucose uptake is lower in the frontal cortex of people >65 years-old despite cognitive scores that are normal for age. (ii) The regional deficit in brain glucose uptake is present in adults <40 years-old who have genetic or lifestyle risk factors for AD but in whom cognitive decline has not yet started. Examples include young adult carriers of presenilin-1 or apolipoprotein E4, and young adults with mild insulin resistance or with a maternal family history of AD. (iii) Regional brain glucose uptake is impaired in AD and mild cognitive impairment (MCI), but brain uptake of ketones (beta-hydroxybutyrate and acetoacetate), remains the same in AD and MCI as in cognitively healthy age-matched controls. These observations point to a brain fuel deficit which appears to be specific to glucose, precedes cognitive decline associated with AD, and becomes more severe as MCI progresses toward AD. Since glucose is the brain's main fuel, we suggest that gradual brain glucose exhaustion is contributing significantly to the onset or progression of AD. (iv) Interventions that raise ketone availability to the brain improve cognitive outcomes in both MCI and AD as well as in acute experimental hypoglycemia. Ketones are the brain's main alternative fuel to glucose and brain ketone uptake is still normal in MCI and in early AD, which would help explain why ketogenic interventions improve some cognitive outcomes in MCI and AD. We suggest that the brain energy deficit needs to be overcome in order to successfully develop more effective therapeutics for AD. At present, oral ketogenic supplements are the most promising means of achieving this goal. PMID:27458340

  5. Alzheimer's Disease. LC Science Tracer Bullet 87-2.

    ERIC Educational Resources Information Center

    Sammons, Vivian O., Comp.

    Alzheimer's disease is characterized by a degeneration and shrinkage of brain tissue; the symptoms include progressive memory loss, bizarre behavior, difficulty in speaking and walking, incontinence, and confusion. Positive diagnosis is possible only upon examination of brain tissue at autopsy. The disease affects not only the patient but also the…

  6. Exploring Symmetry to Assist Alzheimer's Disease Diagnosis

    NASA Astrophysics Data System (ADS)

    Illán, I. A.; Górriz, J. M.; Ramírez, J.; Salas-Gonzalez, D.; López, M.; Padilla, P.; Chaves, R.; Segovia, F.; Puntonet, C. G.

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder first affecting memory functions and then gradually affecting all cognitive functions with behavioral impairments and eventually causing death. Functional brain imaging as Single-Photon Emission Computed Tomography (SPECT) is commonly used to guide the clinician's diagnosis. The essential left-right symmetry of human brains is shown to play a key role in coding and recognition. In the present work we explore the implications of this symmetry in AD diagnosis, showing that recognition may be enhanced when considering this latent symmetry.

  7. Gene Interactions and Structural Brain Change in Early-Onset Alzheimer's Disease Subjects Using the Pipeline Environment

    PubMed Central

    Dinov, Ivo D.; Zamanyan, Alen; Shi, Ran; Genco, Alex; Hobel, Sam; Thompson, Paul M.; Toga, Arthur W.

    2015-01-01

    Objective This article investigates subjects aged 55 to 65 from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database to broaden our understanding of early-onset (EO) cognitive impairment using neuroimaging and genetics biomarkers. Methods Nine of the subjects had EO-AD (Alzheimer's disease) and 27 had EO-MCI (mild cognitive impairment). The 15 most important neuroimaging markers were extracted with the Global Shape Analysis (GSA) Pipeline workflow. The 20 most significant single nucleotide polymorphisms (SNPs) were chosen and were associated with specific neuroimaging biomarkers. Results We identified associations between the neuroimaging phenotypes and genotypes for a total of 36 subjects. Our results for all the subjects taken together showed the most significant associations between rs7718456 and L_hippocampus (volume), and between rs7718456 and R_hippocampus (volume). For the 27 MCI subjects, we found the most significant associations between rs6446443 and R_superior_frontal_gyrus (volume), and between rs17029131 and L_Precuneus (volume). For the nine AD subjects, we found the most significant associations between rs16964473 and L_rectus gyrus (surface area), and between rs12972537 and L_rectus_gyrus (surface area). Conclusion We observed significant correlations between the SNPs and the neuroimaging phenotypes in the 36 EO subjects in terms of neuroimaging genetics. However, larger sample sizes are needed to ensure that the effects will be detectable for a reasonable false-positive error rate using the GSA and Plink Pipeline workflows. PMID:25670955

  8. Coping & Caring: Living with Alzheimer's Disease.

    ERIC Educational Resources Information Center

    Leroux, Charles

    This guide on Alzheimer's disease is for those who care for Alzheimer's patients, as well as those who want to learn more about the disease. It answers these questions: (1) what is Alzheimer's? (2) how does the disease progress and how long does it last? (3) how do families cope? and (4) who can provide assistance and information? The guide also…

  9. Anatomical heterogeneity of Alzheimer disease

    PubMed Central

    Noh, Young; Jeon, Seun; Seo, Sang Won; Kim, Geon Ha; Cho, Hanna; Ye, Byoung Seok; Yoon, Cindy W.; Kim, Hee Jin; Chin, Juhee; Park, Kee Hyung; Heilman, Kenneth M.

    2014-01-01

    Objective: Because the signs associated with dementia due to Alzheimer disease (AD) can be heterogeneous, the goal of this study was to use 3-dimensional MRI to examine the various patterns of cortical atrophy that can be associated with dementia of AD type, and to investigate whether AD dementia can be categorized into anatomical subtypes. Methods: High-resolution T1-weighted volumetric MRIs were taken of 152 patients in their earlier stages of AD dementia. The images were processed to measure cortical thickness, and hierarchical agglomerative cluster analysis was performed using Ward's clustering linkage. The identified clusters of patients were compared with an age- and sex-matched control group using a general linear model. Results: There were several distinct patterns of cortical atrophy and the number of patterns varied according to the level of cluster analyses. At the 3-cluster level, patients were divided into (1) bilateral medial temporal–dominant atrophy subtype (n = 52, ∼34.2%), (2) parietal-dominant subtype (n = 28, ∼18.4%) in which the bilateral parietal lobes, the precuneus, along with bilateral dorsolateral frontal lobes, were atrophic, and (3) diffuse atrophy subtype (n = 72, ∼47.4%) in which nearly all association cortices revealed atrophy. These 3 subtypes also differed in their demographic and clinical features. Conclusions: This cluster analysis of cortical thickness of the entire brain showed that AD dementia in the earlier stages can be categorized into various anatomical subtypes, with distinct clinical features. PMID:25344382

  10. REVIEW: Curcumin and Alzheimer's disease.

    PubMed

    Hamaguchi, Tsuyoshi; Ono, Kenjiro; Yamada, Masahito

    2010-10-01

    Curcumin has a long history of use as a traditional remedy and food in Asia. Many studies have reported that curcumin has various beneficial properties, such as antioxidant, antiinflammatory, and antitumor. Because of the reported effects of curcumin on tumors, many clinical trials have been performed to elucidate curcumin's effects on cancers. Recent reports have suggested therapeutic potential of curcumin in the pathophysiology of Alzheimer's disease (AD). In in vitro studies, curcumin has been reported to inhibit amyloid-β-protein (Aβ) aggregation, and Aβ-induced inflammation, as well as the activities of β-secretase and acetylcholinesterase. In in vivo studies, oral administration of curcumin has resulted in the inhibition of Aβ deposition, Aβ oligomerization, and tau phosphorylation in the brains of AD animal models, and improvements in behavioral impairment in animal models. These findings suggest that curcumin might be one of the most promising compounds for the development of AD therapies. At present, four clinical trials concerning the effects of curcumin on AD has been conducted. Two of them that were performed in China and USA have been reported no significant differences in changes in cognitive function between placebo and curcumin groups, and no results have been reported from two other clinical studies. Additional trials are necessary to determine the clinical usefulness of curcumin in the prevention and treatment of AD. PMID:20406252

  11. An anemia of Alzheimer's disease.

    PubMed

    Faux, N G; Rembach, A; Wiley, J; Ellis, K A; Ames, D; Fowler, C J; Martins, R N; Pertile, K K; Rumble, R L; Trounson, B; Masters, C L; Bush, A I

    2014-11-01

    Lower hemoglobin is associated with cognitive impairment and Alzheimer's disease (AD). Since brain iron homeostasis is perturbed in AD, we investigated whether this is peripherally reflected in the hematological and related blood chemistry values from the Australian Imaging Biomarker and Lifestyle (AIBL) study (a community-based, cross-sectional cohort comprising 768 healthy controls (HC), 133 participants with mild cognitive impairment (MCI) and 211 participants with AD). We found that individuals with AD had significantly lower hemoglobin, mean cell hemoglobin concentrations, packed cell volume and higher erythrocyte sedimentation rates (adjusted for age, gender, APOE-ɛ4 and site). In AD, plasma iron, transferrin, transferrin saturation and red cell folate levels exhibited a significant distortion of their customary relationship to hemoglobin levels. There was a strong association between anemia and AD (adjusted odds ratio (OR)=2.43, confidence interval (CI) (1.31, 4.54)). Moreover, AD emerged as a strong risk factor for anemia on step-down regression, even when controlling for all other available explanations for anemia (adjusted OR=3.41, 95% CI (1.68, 6.92)). These data indicated that AD is complicated by anemia, which may itself contribute to cognitive decline. PMID:24419041

  12. Inflammatory process in Alzheimer's Disease

    PubMed Central

    Meraz-Ríos, Marco A.; Toral-Rios, Danira; Franco-Bocanegra, Diana; Villeda-Hernández, Juana; Campos-Peña, Victoria

    2013-01-01

    Alzheimer Disease (AD) is a neurodegenerative disorder and the most common form of dementia. Histopathologically is characterized by the presence of two major hallmarks, the intracellular neurofibrillary tangles (NFTs) and extracellular neuritic plaques (NPs) surrounded by activated astrocytes and microglia. NFTs consist of paired helical filaments of truncated tau protein that is abnormally hyperphosphorylated. The main component in the NP is the amyloid-β peptide (Aβ), a small fragment of 40–42 amino acids with a molecular weight of 4 kD. It has been proposed that the amyloid aggregates and microglia activation are able to favor the neurodegenerative process observed in AD patients. However, the role of inflammation in AD is controversial, because in early stages the inflammation could have a beneficial role in the pathology, since it has been thought that the microglia and astrocytes activated could be involved in Aβ clearance. Nevertheless the chronic activation of the microglia has been related with an increase of Aβ and possibly with tau phosphorylation. Studies in AD brains have shown an upregulation of complement molecules, pro-inflammatory cytokines, acute phase reactants and other inflammatory mediators that could contribute with the neurodegenerative process. Clinical trials and animal models with non-steroidal anti-inflammatory drugs (NSAIDs) indicate that these drugs may decrease the risk of developing AD and apparently reduce Aβ deposition. Finally, further studies are needed to determine whether treatment with anti-inflammatory strategies, may decrease the neurodegenerative process that affects these patients. PMID:23964211

  13. Hemodynamic aspects of Alzheimer's disease.

    PubMed

    Nagata, Ken; Sato, Mika; Satoh, Yuichi; Watahiki, Yasuhito; Kondoh, Yasushi; Sugawara, Maki; Box, Georgia; Wright, David; Leung, Sumie; Yuya, Hiromichi; Shimosegawa, Eku

    2002-11-01

    Neuroradiological functional imaging techniques demonstrate the patterns of hypoperfusion and hypometabolism that are thought to be useful in the differential diagnosis of Alzheimer's disease (AD) from other dementing disorders. Besides the distribution patterns of perfusion or energy metabolism, vascular transit time (VTT), vascular reactivity (VR), and oxygen extraction fraction (OEF), which can be measured with positron emission tomography (PET), provide hemodynamic aspects of brain pathophysiology. In order to evaluate the hemodynamic features of AD, PET studies were carried out in 20 patients with probable AD and 20 patients with vascular dementia (VaD). The PET findings were not included in their diagnostic process of AD. Using oxygen-15-labeled compounds, cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO(2)), OEF, cerebral blood volume, and VTT were measured quantitatively during resting state. To evaluate VR, CBF was also measured during CO(2) inhalation. There was a significant increase in OEF in and around the parietotemporal cortices, but both VTT and VR were well preserved in patients with AD. By contrast, VR was markedly depressed and VTT was mildly prolonged in patients with VaD. Thus, from the hemodynamic point of view, the preservation of vascular reserve may be a distinct difference between AD and VaD. Furthermore, this indicates a hemodynamic integrity of the vasculature in the level of arterioles in AD.

  14. REVIEW: Curcumin and Alzheimer's disease.

    PubMed

    Hamaguchi, Tsuyoshi; Ono, Kenjiro; Yamada, Masahito

    2010-10-01

    Curcumin has a long history of use as a traditional remedy and food in Asia. Many studies have reported that curcumin has various beneficial properties, such as antioxidant, antiinflammatory, and antitumor. Because of the reported effects of curcumin on tumors, many clinical trials have been performed to elucidate curcumin's effects on cancers. Recent reports have suggested therapeutic potential of curcumin in the pathophysiology of Alzheimer's disease (AD). In in vitro studies, curcumin has been reported to inhibit amyloid-β-protein (Aβ) aggregation, and Aβ-induced inflammation, as well as the activities of β-secretase and acetylcholinesterase. In in vivo studies, oral administration of curcumin has resulted in the inhibition of Aβ deposition, Aβ oligomerization, and tau phosphorylation in the brains of AD animal models, and improvements in behavioral impairment in animal models. These findings suggest that curcumin might be one of the most promising compounds for the development of AD therapies. At present, four clinical trials concerning the effects of curcumin on AD has been conducted. Two of them that were performed in China and USA have been reported no significant differences in changes in cognitive function between placebo and curcumin groups, and no results have been reported from two other clinical studies. Additional trials are necessary to determine the clinical usefulness of curcumin in the prevention and treatment of AD.

  15. The Compression Flow as a Measure to Estimate the Brain Connectivity Changes in Resting State fMRI and 18FDG-PET Alzheimer's Disease Connectomes.

    PubMed

    Zippo, Antonio G; Castiglioni, Isabella; Borsa, Virginia M; Biella, Gabriele E M

    2015-01-01

    The human brain appears organized in compartments characterized by seemingly specific functional purposes on many spatial scales. A complementary functional state binds information from specialized districts to return what is called integrated information. These fundamental network dynamics undergoes to severe disarrays in diverse degenerative conditions such as Alzheimer's Diseases (AD). The AD represents a multifarious syndrome characterized by structural, functional, and metabolic landmarks. In particular, in the early stages of AD, adaptive functional modifications of the brain networks mislead initial diagnoses because cognitive abilities may result indiscernible from normal subjects. As a matter of facts, current measures of functional integration fail to catch significant differences among normal, mild cognitive impairment (MCI) and even AD subjects. The aim of this work is to introduce a new topological feature called Compression Flow (CF) to finely estimate the extent of the functional integration in the brain networks. The method uses a Monte Carlo-like estimation of the information integration flows returning the compression ratio between the size of the injected information and the size of the condensed information within the network. We analyzed the resting state connectomes of 75 subjects of the Alzheimer's Disease Neuroimaging Initiative 2 (ADNI) repository. Our analyses are focused on the 18FGD-PET and functional MRI (fMRI) acquisitions in several clinical screening conditions. Results indicated that CF effectively discriminate MCI, AD and normal subjects by showing a significant decrease of the functional integration in the AD and MCI brain connectomes. This result did not emerge by using a set of common complex network statistics. Furthermore, CF was best correlated with individual clinical scoring scales. In conclusion, we presented a novel measure to quantify the functional integration that resulted efficient to discriminate different stages of

  16. Two-photon microscopy for real-time monitoring of focused ultrasound-mediated drug delivery to the brain in a mouse model of Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Burgess, Alison; Eterman, Naomi; Aubert, Isabelle; Hynynen, Kullervo

    2013-02-01

    There is substantial evidence that focused ultrasound (FUS) in combination with microbubble contrast agent can cause disruption of the blood-brain barrier (BBB) to aid in drug delivery to the brain. We have previously demonstrated that FUS efficiently delivers antibodies against amyloid-β peptides (Aβ) through the BBB, leading to a reduction in amyloid pathology at 4 days in a mouse model of Alzheimer's disease. In the current study, we used two-photon microscopy to characterize the effect of FUS in real time on amyloid pathology in the mouse brain. Mice were anesthetized and a cranial window was made in the skull. A custom-built ultrasound transducer was fixed to a coverslip and attached to the skull, covering the cranial window. Methoxy-X04 [2-5mg/kg] delivered intravenously 1 hr prior to the experiment clearly labelled the Aβ surrounding the vessels and the amyloid plaques in the cortex. Dextran conjugated Texas Red (70kDa) administered intravenously, confirmed BBB disruption. BBB disruption occurred in transgenic and non-transgenic animals at similar ultrasound pressures tested. However, the time required for BBB closure following FUS was longer in the Tg mice. We have conjugated Aβ antibodies to the fluorescent molecule FITC for real time monitoring of the antibody distribution in the brain. Our current experiments are aimed at optimizing the parameters to achieve maximal fluorescent intensity of the BAM10 antibody at the plaque surface. Two-photon microscopy has proven to be a valuable tool for evaluating the efficacy of FUS mediated drug delivery, including antibodies, to the Alzheimer brain.

  17. Multi-Family Psychoeducational Support Group Therapy for Families with a Member Afflicted with Irreversible Brain Syndrome (Alzheimer's Disease): Report of a Pilot Study.

    ERIC Educational Resources Information Center

    Paley, Evelyn S.; And Others

    Alzheimers Disease (AD), an incurable disability which afflicts older adults, can have devastating emotional consequences for the victim and the family. In an attempt to determine the effectiveness of multifamily psychoeducational support, group therapy (MFPSGT), 22 persons (13 families) from the Alzheimer's Disease and Related Disorders…

  18. Posture Recognition in Alzheimer's Disease

    ERIC Educational Resources Information Center

    Mozaz, Maria; Garaigordobil, Maite; Rothi, Leslie J. Gonzalez; Anderson, Jeffrey; Crucian, Gregory P.; Heilman, Kenneth M.

    2006-01-01

    Background: Apraxia is neurologically induced deficit in the ability perform purposeful skilled movements. One of the most common forms is ideomotor apraxia (IMA) where spatial and temporal production errors are most prevalent. IMA can be associated Alzheimer's disease (AD), even early in its course, but is often not identified possibly because…

  19. [Alzheimer's disease, caregiving and frailty].

    PubMed

    de Peretti, Eva; Villars, Hélène

    2015-01-01

    Caring for a person with Alzheimer's disease often sees the elderly carer at risk of succumbing to frailty. The chronic stress which comes with this caregiving can lead to physical and emotional exhaustion, for which the physiological reserves of the ageing person may be insufficient. The concept of frailty may help to improve the understanding of this vulnerability.

  20. Assessing outcomes in Alzheimer disease.

    PubMed

    Schneider, L S

    2001-08-01

    To gain a better overview of the effectiveness of treatment of patients with Alzheimer disease (AD), areas such as cognition, activities of daily living (ADL), behavior, caregiver burden, quality of life and economics need to be assessed. A number of instruments are available for assessing these domains, many of which are reviewed in this article. These include the cognitive subscale of the Alzheimer's Disease Assessment Scale (the standard instrument for the measurement of efficacy in dementia trials), scales that assess AD patients' abilities to perform ADL (including the Disability Assessment for Dementia scale and the Alzheimer's Disease Cooperative Study-Activities of Daily Living), scales to assess behavioral symptoms in dementia (including the Neuropsychiatric Inventory and the Behavioral Pathology in Alzheimer's Disease Rating Scale), scales for assessing global clinical change, and methods for assessing caregiver time, quality of life and health economics. Each instrument has its own advantages and disadvantages. However, the instruments used need to be selected carefully to provide credible and informative outcome data. PMID:11669509

  1. Alzheimer's disease: An acquired neurodegenerative laminopathy

    PubMed Central

    Frost, Bess

    2016-01-01

    ABSTRACT The nucleus is typically depicted as a sphere encircled by a smooth surface of nuclear envelope. For most cell types, this depiction is accurate. In other cell types and in some pathological conditions, however, the smooth nuclear exterior is interrupted by tubular invaginations of the nuclear envelope, often referred to as a “nucleoplasmic reticulum,” into the deep nuclear interior. We have recently reported a significant expansion of the nucleoplasmic reticulum in postmortem human Alzheimer's disease brain tissue. We found that dysfunction of the nucleoskeleton, a lamin-rich meshwork that coats the inner nuclear membrane and associated invaginations, is causal for Alzheimer's disease-related neurodegeneration in vivo. Additionally, we demonstrated that proper function of the nucleoskeleton is required for survival of adult neurons and maintaining genomic architecture. Here, we elaborate on the significance of these findings in regard to pathological states and physiological aging, and discuss cellular causes and consequences of nuclear envelope invagination. PMID:27167528

  2. [Genetic aspects of Alzheimer's disease (Review)].

    PubMed

    El Kadmiri, N; Hamzi, K; El Moutawakil, B; Slassi, I; Nadifi, S

    2013-12-01

    Alzheimer's disease is a degenerative brain disorder, which concerns memory, cognition and behavior pattern. Its etiology is unknown, it is characterized by typical histological lesions: senile plaques and neuro-fibrillary tangles. Alzheimer's disease is a multifactorial pathology, characterized by interactions between genetic and environmental factors. Genetic factors concern first of all the exceptional monogenic forms, characterized by early onset (<60 years), autosomal dominant forms. Mutations of the genes coding for amyloid-ß precursor protein or preselinins 1 and 2 are involved. The much more frequent sporadic forms also have genetic factors, the best studied being the apolipoprotein E4 coding allele and some more recent genotypes which will be mentioned. No causal, only symptomatic treatments are available.

  3. Alzheimer's disease: An acquired neurodegenerative laminopathy.

    PubMed

    Frost, Bess

    2016-05-01

    The nucleus is typically depicted as a sphere encircled by a smooth surface of nuclear envelope. For most cell types, this depiction is accurate. In other cell types and in some pathological conditions, however, the smooth nuclear exterior is interrupted by tubular invaginations of the nuclear envelope, often referred to as a "nucleoplasmic reticulum," into the deep nuclear interior. We have recently reported a significant expansion of the nucleoplasmic reticulum in postmortem human Alzheimer's disease brain tissue. We found that dysfunction of the nucleoskeleton, a lamin-rich meshwork that coats the inner nuclear membrane and associated invaginations, is causal for Alzheimer's disease-related neurodegeneration in vivo. Additionally, we demonstrated that proper function of the nucleoskeleton is required for survival of adult neurons and maintaining genomic architecture. Here, we elaborate on the significance of these findings in regard to pathological states and physiological aging, and discuss cellular causes and consequences of nuclear envelope invagination.

  4. Alzheimer's disease: An acquired neurodegenerative laminopathy.

    PubMed

    Frost, Bess

    2016-05-01

    The nucleus is typically depicted as a sphere encircled by a smooth surface of nuclear envelope. For most cell types, this depiction is accurate. In other cell types and in some pathological conditions, however, the smooth nuclear exterior is interrupted by tubular invaginations of the nuclear envelope, often referred to as a "nucleoplasmic reticulum," into the deep nuclear interior. We have recently reported a significant expansion of the nucleoplasmic reticulum in postmortem human Alzheimer's disease brain tissue. We found that dysfunction of the nucleoskeleton, a lamin-rich meshwork that coats the inner nuclear membrane and associated invaginations, is causal for Alzheimer's disease-related neurodegeneration in vivo. Additionally, we demonstrated that proper function of the nucleoskeleton is required for survival of adult neurons and maintaining genomic architecture. Here, we elaborate on the significance of these findings in regard to pathological states and physiological aging, and discuss cellular causes and consequences of nuclear envelope invagination. PMID:27167528

  5. Genetic heterogeneity and Alzheimer`s disease

    SciTech Connect

    Schellenberg, G.D.; Wijsman, E.M.; Bird, T.D.

    1994-09-01

    In some early-onset Alzheimer`s disease (AD) families, inheritance is autosomal dominant. (Early-onset AD is arbitarily defined as onset at {le} 60 years.) Two loci have been identified which are causative for early-onset familial AD (FAD). One is the amyloid precursor protein gene in which specific mutation have been identified. The second is a locus at 14q24.3 (AD3) which has been localized by linkage analysis; the gene and specific mutations have not been identified. Linkage studies place this locus between D14S61 and D14S63. These 2 loci, however, do not account for all early-onset FAD. The Volga German (VG) kindreds are descendants of families which emigrated from Germany to the Volga river region of Russia and subsequently to the US; AD in these families is hypothesized to be the result of a common genetic founder. The average age-at-onset in these families is 57 years. Linkage analysis for this group has been negative for the APP gene and for chromosome 14 markers. Thus, there is at least 1 other early-onset FAD locus. Recently, the {epsilon}4 allele of apolipoprotein E (ApoE) was identified as a risk-factor for late-onset AD. In a series of 53 late-onset kindreds, a strong genetic association was observed between the ApoE {epsilon}4 allele and AD. However, when linkage analysis was performed using a highly polymorphic locus at the ApoCII gene, which is within 30 kb of ApoE, significant evidence for co-segregation was not observed. This and other data suggests that while ApoE is an age-at-onset modifying locus, another gene(s), located elsewhere, contribute(s) to late-onset AD. Thus, there is probably at least 1 other late-onset locus. Once the VG locus is identified, it will be possible to determine whether an allelic variant of this locus is responsible for late-onset FAD.

  6. Perception of Alzheimer Disease in Iranian Traditional Medicine

    PubMed Central

    Saifadini, Rostam; Tajadini, Haleh; Choopani, Rasool; Mehrabani, Mitra; Kamalinegad, Mohamad; Haghdoost, Aliakbar

    2016-01-01

    Context: Alzheimer disease (AD) is the most common cause of dementia. In regards to the world’s aging population, control and treatment of AD will be one of the major concerns of global public health in the next century. Alzheimer disease was not mentioned with the same phrase or its equivalent in traditional medical texts. The main of present paper was to investigate symptoms and causes of alzheimer disease from the view point of Iranian traditional medicine. Evidence Acquisition: In this qualitative study, we searched reliable sources of Iranian traditional medicine such as Canon of Medicide by Avicenna (Al-Quanon fi- tibb), Aghili cure by Aghili’s (Molajat-E-aghili), Tib-E-Akbari, Exire -E-Aazam and Sharh-E-Asbab and some reliable resources of neurology were probed base on keywords to find a disease that had the most overlap in terms of symptoms with alzheimer disease. By taking from the relevant materials, the extracted texts were compared and analyzed. Results: Findings showed that alzheimer disease has the most overlap with Nesyan (fisad-e-zekr, fisad-e-fekr and fisad-e-takhayol) symptoms in Iranian traditional medicine. Although this is not a perfect overlap and there are causes, including coldness and dryness of the brain or coldness and wetness that could also lead to alzheimer disease according to Iranian traditional medicine. Conclusions: According to Iranian traditional medicine, The brain dystemperement is considered the main causes of alzheimer disease. By correcting the brain dystemperement, alzheimer can be well managed. This study helps to suggest a better strategy for preventing and treating alzheimer in the future. PMID:27247784

  7. Alzheimer's disease and euthanasia.

    PubMed

    Alvargonzález, David

    2012-12-01

    Employing the tenets of philosophical materialism, this paper discusses the ethical debate surrounding assisted suicide for persons suffering end-stage Alzheimer's. It first presents a classification of the dissociative situations between "human individual" and "human person". It then moves on to discuss challenges to diagnosed persons and their caregivers in relation to the cardinal virtues of Spinozistic ethics--strength of character (fortitudo), firmness (animositas) and generosity (generositas). Finally, a number of ideas attached to the debate--"right of choice", "death with dignity", "quality of life" and "compassion in dying"--are discussed in order to clarify their foundations. PMID:22939533

  8. Evaluation of oxidative stress in the brain of a transgenic mouse model of Alzheimer disease by in vivo electron paramagnetic resonance imaging.

    PubMed

    Matsumura, Akihiro; Emoto, Miho C; Suzuki, Syuuichirou; Iwahara, Naotoshi; Hisahara, Shin; Kawamata, Jun; Suzuki, Hiromi; Yamauchi, Ayano; Sato-Akaba, Hideo; Fujii, Hirotada G; Shimohama, Shun

    2015-08-01

    Alzheimer disease (AD) is a neurodegenerative disease clinically characterized by progressive cognitive dysfunction. Deposition of amyloid-β (Aβ) peptides is the most important pathophysiological hallmark of AD. Oxidative stress induced by reactive oxygen species is prominent in AD, and several reports suggest the relationship between a change in redox status and AD pathology containing progressive Aβ deposition, the activation of glial cells, and mitochondrial dysfunction. Therefore, we performed immunohistochemical analysis using a transgenic mouse model of AD (APdE9) and evaluated the activity of superoxide dismutase in brain tissue homogenates of APdE9 mice in vitro. Together with those analyses, in vivo changes in redox status with age in both wild-type (WT) and APdE9 mouse brains were measured noninvasively by three-dimensional electron paramagnetic resonance (EPR) imaging using nitroxide (3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy) as a redox-sensitive probe. Both methods found similar changes in redox status with age, and in particular a significant change in redox status in the hippocampus was observed noninvasively by EPR imaging between APdE9 mice and age-matched WT mice from 9 to 18 months of age. EPR imaging clearly visualized the accelerated change in redox status of APdE9 mouse brain compared with WT. The evaluation of the redox status in the brain of AD model rodents by EPR imaging should be useful for diagnostic study of AD.

  9. Twenty years of the Alzheimer's disease amyloid hypothesis: a genetic perspective.

    PubMed

    Tanzi, Rudolph E; Bertram, Lars

    2005-02-25

    From Alois Alzheimer's description of Auguste D.'s brain in 1907 to George Glenner's biochemical dissection of beta-amyloid in 1984, the "amyloid hypothesis" of Alzheimer's disease has continued to gain support over the past two decades, particularly from genetic studies. Here we assess the amyloid hypothesis based on both known and putative Alzheimer's disease genes.

  10. Behavioral stress causes mitochondrial dysfunction via ABAD up-regulation and aggravates plaque pathology in the brain of a mouse model of Alzheimer disease.

    PubMed

    Seo, Ji-Seon; Lee, Kang-Woo; Kim, Tae-Kyung; Baek, In-Sun; Im, Joo-Young; Han, Pyung-Lim

    2011-06-01

    Basic and clinical studies have reported that behavioral stress worsens the pathology of Alzheimer disease (AD), but the underlying mechanism has not been clearly understood. In this study, we determined the mechanism by which behavioral stress affects the pathogenesis of AD using Tg-APPswe/PS1dE9 mice, a murine model of AD. Tg-APPswe/PS1dE9 mice that were restrained for 2h daily for 16 consecutive days (2-h/16-day stress) from 6.5months of age had significantly increased Aβ(1-42) levels and plaque deposition in the brain. The 2-h/16-day stress increased oxidative stress and induced mitochondrial dysfunction in the brain. Treatment with glucocorticoid (corticosterone) and Aβ in SH-SY5Y cells increased the expression of 17β-hydroxysteroid dehydrogenase (ABAD), mitochondrial dysfunction, and levels of ROS, whereas blockade of ABAD expression by siRNA-ABAD in SH-SY5Y cells suppressed glucocorticoid-enhanced mitochondrial dysfunction and ROS accumulation. The 2-h/16-day stress up-regulated ABAD expression in mitochondria in the brain of Tg-APPswe/PS1dE9 mice. Moreover, all visible Aβ plaques were costained with anti-ABAD in the brains of Tg-APPswe/PS1dE9 mice. Together, these results suggest that behavioral stress aggravates plaque pathology and mitochondrial dysfunction via up-regulation of ABAD in the brain of a mouse model of AD.

  11. Quantitative measurement of alternatively spliced amyloid precursor protein mRNA expression in Alzheimer's disease and normal brain by S1 nuclease protection analysis.

    PubMed

    Jacobsen, J S; Blume, A J; Vitek, M P

    1991-01-01

    We have used an S1 nuclease protection strategy to measure alternatively spliced amyloid precursor protein (APP) mRNAs associated with Alzheimer's disease (AD) to determine whether the expression of either one or more of the transcripts correlate with observed amyloid plaque pathology. Comparison of AD with normal cortex reveals that increasing plaque density parallels an increase in the fraction of APP-695 and a corresponding decrease in APP-770 and 751 mRNA fractions. A specific increase of APP-695, the protease inhibitor-lacking APP RNA form, in those brain regions most involved with amyloid plaque formation, suggests that an imbalance in the protease inhibitor is potentially significant in the disease. These data are consistent with cellular/tissue region-specific regulation of alternative splicing accounting for AD-related changes in the expression of APP mRNA forms.

  12. Brain beta-amyloid measures and magnetic resonance imaging atrophy both predict time-to-progression from mild cognitive impairment to Alzheimer's disease.

    PubMed

    Jack, Clifford R; Wiste, Heather J; Vemuri, Prashanthi; Weigand, Stephen D; Senjem, Matthew L; Zeng, Guang; Bernstein, Matt A; Gunter, Jeffrey L; Pankratz, Vernon S; Aisen, Paul S; Weiner, Michael W; Petersen, Ronald C; Shaw, Leslie M; Trojanowski, John Q; Knopman, David S

    2010-11-01

    Biomarkers of brain Aβ amyloid deposition can be measured either by cerebrospinal fluid Aβ42 or Pittsburgh compound B positron emission tomography imaging. Our objective was to evaluate the ability of Aβ load and neurodegenerative atrophy on magnetic resonance imaging to predict shorter time-to-progression from mild cognitive impairment to Alzheimer's dementia and to characterize the effect of these biomarkers on the risk of progression as they become increasingly abnormal. A total of 218 subjects with mild cognitive impairment were identified from the Alzheimer's Disease Neuroimaging Initiative. The primary outcome was time-to-progression to Alzheimer's dementia. Hippocampal volumes were measured and adjusted for intracranial volume. We used a new method of pooling cerebrospinal fluid Aβ42 and Pittsburgh compound B positron emission tomography measures to produce equivalent measures of brain Aβ load from either source and analysed the results using multiple imputation methods. We performed our analyses in two phases. First, we grouped our subjects into those who were 'amyloid positive' (n = 165, with the assumption that Alzheimer's pathology is dominant in this group) and those who were 'amyloid negative' (n = 53). In the second phase, we included all 218 subjects with mild cognitive impairment to evaluate the biomarkers in a sample that we assumed to contain a full spectrum of expected pathologies. In a Kaplan-Meier analysis, amyloid positive subjects with mild cognitive impairment were much more likely to progress to dementia within 2 years than amyloid negative subjects with mild cognitive impairment (50 versus 19%). Among amyloid positive subjects with mild cognitive impairment only, hippocampal atrophy predicted shorter time-to-progression (P < 0.001) while Aβ load did not (P = 0.44). In contrast, when all 218 subjects with mild cognitive impairment were combined (amyloid positive and negative), hippocampal atrophy and Aβ load predicted

  13. Immunotherapeutic Approaches to Alzheimer's Disease

    NASA Astrophysics Data System (ADS)

    Monsonego, Alon; Weiner, Howard L.

    2003-10-01

    Although neurodegenerative diseases such as Alzheimer's disease are not classically considered mediated by inflammation or the immune system, in some instances the immune system may play an important role in the degenerative process. Furthermore, it has become clear that the immune system itself may have beneficial effects in nervous system diseases considered neurodegenerative. Immunotherapeutic approaches designed to induce a humoral immune response have recently been developed for the treatment of Alzheimer's disease. These studies have led to human trials that resulted in both beneficial and adverse effects. In animal models, it has also been shown that immunotherapy designed to induce a cellular immune response may be of benefit in central nervous system injury, although T cells may have either a beneficial or detrimental effect depending on the type of T cell response induced. These areas provide a new avenue for exploring immune system-based therapy of neurodegenerative diseases and will be discussed here with a primary focus on Alzheimer's disease. We will also discuss how these approaches affect microglia activation, which plays a key role in therapy of such diseases.

  14. Clinical Genetics of Alzheimer's Disease

    PubMed Central

    Zou, Zhangyu; Liu, Changyun; Che, Chunhui; Huang, Huapin

    2014-01-01

    Alzheimer's disease (AD) is the most common progressive neurodegenerative disease and the most common form of dementia in the elderly. It is a complex disorder with environmental and genetic components. There are two major types of AD, early onset and the more common late onset. The genetics of early-onset AD are largely understood with mutations in three different genes leading to the disease. In contrast, while susceptibility loci and alleles associated with late-onset AD have been identified using genetic association studies, the genetics of late-onset Alzheimer's disease are not fully understood. Here we review the known genetics of early- and late-onset AD, the clinical features of EOAD according to genotypes, and the clinical implications of the genetics of AD. PMID:24955352

  15. Synaptic Cell Adhesion Molecules in Alzheimer's Disease

    PubMed Central

    Leshchyns'ka, Iryna

    2016-01-01

    Alzheimer's disease (AD) is a neurodegenerative brain disorder associated with the loss of synapses between neurons in the brain. Synaptic cell adhesion molecules are cell surface glycoproteins which are expressed at the synaptic plasma membranes of neurons. These proteins play key roles in formation and maintenance of synapses and regulation of synaptic plasticity. Genetic studies and biochemical analysis of the human brain tissue, cerebrospinal fluid, and sera from AD patients indicate that levels and function of synaptic cell adhesion molecules are affected in AD. Synaptic cell adhesion molecules interact with Aβ, a peptide accumulating in AD brains, which affects their expression and synaptic localization. Synaptic cell adhesion molecules also regulate the production of Aβ via interaction with the key enzymes involved in Aβ formation. Aβ-dependent changes in synaptic adhesion affect the function and integrity of synapses suggesting that alterations in synaptic adhesion play key roles in the disruption of neuronal networks in AD. PMID:27242933

  16. Is Alzheimer's disease a homogeneous disease entity?

    PubMed

    Korczyn, Amos D

    2013-10-01

    The epidemic proportions of dementia in old age are a cause of great concern for the medical profession and the society at large. It is customary to consider Alzheimer's disease (AD) as the most common cause of dementia, and vascular dementia (VaD) as being the second. This dichotomous view of a primary neurodegenerative disease as opposed to a disorder where extrinsic factors cause brain damage led to separate lines of research in these two entities. New biomarkers, particularly the introduction of modern neuroimaging and cerebrospinal fluid changes, have, in recent years, helped to identify anatomical and chemical changes of VaD and of AD. Nevertheless, there is a substantial difference between the two entities. While it is clear that VaD is a heterogeneous entity, AD is supposed to be a single disorder. Nobody attempts to use CADASIL as a template to develops treatment for sporadic VaD. On the other hand, early-onset AD is used to develop therapy for sporadic AD. This paper will discuss the problems relating to this false concept and its consequences. PMID:23933662

  17. Pituitary gland levels of mercury, selenium, iron, and zinc in an Alzheimer`s disease study

    SciTech Connect

    Cornett, C.R.; Markesbery, W.R.; Wekstein, D.R.; Ehmann, W.D.

    1996-12-31

    Mercury, iron, selenium, and zinc imbalances have been observed in comparisons between Alzheimer`s disease (AD) and control subject brains. Analyses of the pituitary gland have demonstrated that this organ retains relatively high concentrations of trace elements, including mercury, iron, and zinc. Our previous work has shown that the pituitary glands of AD and control subjects are typically higher in these trace elements than brain samples from the same subject. Instrumental neutron activation analysis (INAA) was used to compare the pituitary trace element levels of AD and control subjects. This study also describes the intrasubject relationships of brain trace element levels to those in the pituitary gland of AD and control subjects.

  18. Alzheimer's Disease Information Page

    MedlinePlus

    ... the worsening breakdown of the connections between certain neurons in the brain and their eventual death. AD ... with a collection of additional proteins, remnants of neurons, and bits and pieces of other nerve cells. ...

  19. Is brain copper deficiency in Alzheimer's, Lewy body, and Creutzfeldt Jakob diseases the common key for a free radical mechanism and oxidative stress-induced damage?

    PubMed

    Deloncle, Roger; Guillard, Olivier

    2015-01-01

    In Alzheimer's (AD), Lewy body (LBD), and Creutzfeldt Jakob (CJD) diseases, similar pathological hallmarks have been described, one of which is brain deposition of abnormal protease-resistant proteins. For these pathologies, copper bound to proteins is able to protect against free radicals by reduction from cupric Cu++ to cupreous Cu+. We have previously demonstrated in bovine brain homogenate that free radicals produce proteinase K-resistant prion after manganese is substituted for copper. Since low brain copper levels have been described in transmissible spongiform encephalopathies, in substantia nigra in Parkinson's disease, and in various brain regions in AD, LBD, and CJD, a mechanism has been proposed that may underlie the neurodegenerative processes that occur when copper protection against free radicals is impaired. In peptide sequences, the alpha acid proton near the peptide bond is highly mobile and can be pulled out by free radicals. It will produce a trivalent α-carbon radical and induce a free radical chain process that will generate a D-amino acid configuration in the peptide sequence. Since only L-amino acids are physiologically present in mammalian (human) proteins, it may be supposed that only physiological L-peptides can be recycled by physiological enzymes such as proteases. If a D-amino acid is found in the peptide sequence subsequent to deficient copper protection against free radicals, it will not be recognized and might alter the proteasome L-amino acid recycling from brain peptides. In the brain, there will result an accumulation of abnormal protease-resistant proteins such as those observed in AD, LBD, and CJD.

  20. The Association Between Retinal Neuronal Layer and Brain Structure is Disrupted in Patients with Cognitive Impairment and Alzheimer's Disease.

    PubMed

    Liu, Siwei; Ong, Yi-Ting; Hilal, Saima; Loke, Yng Miin; Wong, Tien Y; Chen, Christopher Li-Hsian; Cheung, Carol Y; Zhou, Juan

    2016-09-01

    Both healthy and pathological aging due to Alzheimer's disease (AD) are associated with decreased brain grey matter volume (GMV) and disrupted white matter (WM) microstructure. Thinner macular ganglion cell-inner plexiform layer (GC-IPL) measured by spectral-domain optical coherence tomography has been reported in patients with AD and mild cognitive impairment. Emerging evidence suggested a link between thinner GC-IPL and lower GMV in subjects with no dementia using region-of-interest-based approach. However, it remains unknown whether GC-IPL thickness is associated with brain WM microstructure and how such association differed between normal and cognitively impaired subjects. Here, for subjects with no cognitive impairment (NCI), thinner GC-IPL was associated with lower WM microstructure integrity in the superior longitudinal fasciculus, inferior fronto-occipital fasciculus, corticospinal tracts, anterior thalamic radiation, and cingulum regions, while it was weakly associated with lower GMV in visual cortex and cerebellum. Nevertheless, these retina-brain associations were disrupted in the presence of cognitive impairment. Correlations between GMV and GC-IPL were lost in patients with cognitive impairment but no dementia (CIND) and AD patients. GC-IPL was related to WM microstructural disruption in similar regions with decreased significance. In contrast, lower WM microstructure integrity in the fornix showed a trend of correlation with thinner GC-IPL in both CIND and AD but not NCI. Collectively, our findings suggest the possible physiological retina-brain relationship in healthy aging, which might be disrupted by disease-induced changes in patients with cognitive impairment. Longitudinal study with larger patient sample should follow to confirm the disease mechanism behind these retina-brain relationship changes. PMID:27567815

  1. The cholinergic hypothesis of Alzheimer's disease: a review of progress

    PubMed Central

    Francis, P.; Palmer, A.; Snape, M.; Wilcock, G.

    1999-01-01

    Alzheimer's disease is one of the most common causes of mental deterioration in elderly people, accounting for around 50%-60% of the overall cases of dementia among persons over 65 years of age. The past two decades have witnessed a considerable research effort directed towards discovering the cause of Alzheimer's disease with the ultimate hope of developing safe and effective pharmacological treatments. This article examines the existing scientific applicability of the original cholinergic hypothesis of Alzheimer's disease by describing the biochemical and histopathological changes of neurotransmitter markers that occur in the brains of patients with Alzheimer's disease both at postmortem and neurosurgical cerebral biopsy and the behavioural consequences of cholinomimetic drugs and cholinergic lesions. Such studies have resulted in the discovery of an association between a decline in learning and memory, and a deficit in excitatory amino acid (EAA) neurotransmission, together with important roles for the cholinergic system in attentional processing and as a modulator of EAA neurotransmission. Accordingly, although there is presently no "cure" for Alzheimer's disease, a large number of potential therapeutic interventions have emerged that are designed to correct loss of presynaptic cholinergic function. A few of these compounds have confirmed efficacy in delaying the deterioration of symptoms of Alzheimer's disease, a valuable treatment target considering the progressive nature of the disease. Indeed, three compounds have received European approval for the treatment of the cognitive symptoms of Alzheimer's disease, first tacrine and more recently, donepezil and rivastigmine, all of which are cholinesterase inhibitors.

 PMID:10071091

  2. Novel piperine-loaded Tween-integrated monoolein cubosomes as brain-targeted oral nanomedicine in Alzheimer's disease: pharmaceutical, biological, and toxicological studies.

    PubMed

    Elnaggar, Yosra S R; Etman, Samar M; Abdelmonsif, Doaa A; Abdallah, Ossama Y

    2015-01-01

    Alzheimer's disease (AD) is one of the most patient devastating central nervous system diseases with no curative therapy. An effective oral therapy with brain-targeting potential is required that is hampered by blood-brain barrier. Piperine (PIP) is a natural alkaloid with memory enhancing potentials. Oral PIP delivery suffers from its hydrophobicity and first-pass metabolism. In this study, novel Tween-modified monoolein cubosomes (T-cubs) were elaborated as bioactive nanocarriers for brain-targeted oral delivery of PIP. Seven liquid crystalline nanoparticles (cubosomes) were prepared testing different bioactive surfactants (Tween 80, poloxamer, and Cremophor). Full in vitro characterization was carried out based on particle size, zeta potential, polydispersity index, entrapment efficiency, and in vitro release. Morphological examination and structure elucidation were performed using transmission and polarizing microscopes. Sporadic dementia of Alzheimer's type was induced in 42 male Wistar rats on which full behavioral and biochemical testing was conducted. Brain toxicity was assessed based on Caspase-3 assay for apoptosis and tumor necrosis factor-α for inflammation. Liver and kidney toxicity studies were conducted as well. Among others, T-cubs exhibited optimum particle size (167.00±10.49 nm), polydispersity index (0.18±0.01), and zeta potential (-34.60±0.47 mv) with high entrapment efficiency (86.67%±0.62%). Cubs could significantly sustain PIP in vitro release. In vivo studies revealed T-cubs potential to significantly enhance PIP cognitive effect and even restore cognitive function to the normal level. Superiority of T-cubs over others suggested brain-targeting effect of Tween. Toxicological studies contended safety of cubs on kidney, liver, and even brain. T-cubs exhibited potential anti-inflammatory and anti-apoptotic activity of loaded PIP, indicating potential to stop AD progression that was first suggested in this article. Novel oral nanoparticles

  3. Role of P-glycoprotein in mediating rivastigmine effect on amyloid-β brain load and related pathology in Alzheimer's disease mouse model.

    PubMed

    Mohamed, Loqman A; Keller, Jeffrey N; Kaddoumi, Amal

    2016-04-01

    Recently, we showed that rivastigmine decreased amyloid-β (Aβ) brain load in aged rats by enhancing its clearance across the blood-brain barrier (BBB) via upregulation of P-glycoprotein (P-gp) and low-density lipoprotein receptor-related protein 1 (LRP1). Here, we extend our previous work to clarify P-gp role in mediating rivastigmine effect on Aβ brain levels and neuroprotection in a mouse model of Alzheimer's disease (AD) that expresses different levels of P-gp. APPSWE mice were bred with mdr1a/b knockout mice to produce littermates that were divided into three groups; APP(+)/mdr1(+/+), APP(+)/mdr1(+/-) and APP(+)/mdr1(-/-). Animals received rivastigmine treatment (0.3mg/kg/day) or vehicle for 8weeks using Alzet osmotic mini-pumps. ELISA analysis of brain homogenates for Aβ showed rivastigmine treatment to significantly decrease Aβ brain load in APP(+)/mdr1(+/+) by 25% and in APP(+)/mdr1(+/-) mice by 21% compared to their vehicle treated littermates, but not in APP(+)/mdr1(-/-) mice. In addition, rivastigmine reduced GFAP immunostaining of astrocytes by 50% and IL-1β brain level by 43% in APP(+)/mdr1(+/+) mice, however its effect was less pronounced in P-gp knockout mice. Moreover, rivastigmine demonstrated a P-gp expression dependent neuroprotective effect that was highest in APP(+)/mdr1(+/+)>APP(+)/mdr1(+/-)>APP(+)/mdr1(-/-) as determined by expression of synaptic markers PSD-95 and SNAP-25 using Western blot analysis. Collectively, our results suggest that P-gp plays important role in mediating rivastigmine non-cholinergic beneficial effects, including Aβ brain load reduction, neuroprotective and anti-inflammatory effects in the AD mouse models. PMID:26780497

  4. Intraperitoneal injection of the pancreatic peptide amylin potently reduces behavioral impairment and brain amyloid pathology in murine models of Alzheimer's disease.

    PubMed

    Zhu, H; Wang, X; Wallack, M; Li, H; Carreras, I; Dedeoglu, A; Hur, J-Y; Zheng, H; Li, H; Fine, R; Mwamburi, M; Sun, X; Kowall, N; Stern, R A; Qiu, W Q

    2015-02-01

    Amylin, a pancreatic peptide, and amyloid-beta peptides (Aβ), a major component of Alzheimer's disease (AD) brain, share similar β-sheet secondary structures, but it is not known whether pancreatic amylin affects amyloid pathogenesis in the AD brain. Using AD mouse models, we investigated the effects of amylin and its clinical analog, pramlintide, on AD pathogenesis. Surprisingly, chronic intraperitoneal (i.p.) injection of AD animals with either amylin or pramlintide reduces the amyloid burden as well as lowers the concentrations of Aβ in the brain. These treatments significantly improve their learning and memory assessed by two behavioral tests, Y maze and Morris water maze. Both amylin and pramlintide treatments increase the concentrations of Aβ1-42 in cerebral spinal fluid (CSF). A single i.p. injection of either peptide also induces a surge of Aβ in the serum, the magnitude of which is proportionate to the amount of Aβ in brain tissue. One intracerebroventricular injection of amylin induces a more significant surge in serum Aβ than one i.p. injection of the peptide. In 330 human plasma samples, a positive association between amylin and Aβ1-42 as well as Aβ1-40 is found only in patients with AD or amnestic mild cognitive impairment. As amylin readily crosses the blood-brain barrier, our study demonstrates that peripheral amylin's action on the central nervous system results in translocation of Aβ from the brain into the CSF and blood that could be an explanation for a positive relationship between amylin and Aβ in blood. As naturally occurring amylin may play a role in regulating Aβ in brain, amylin class peptides may provide a new avenue for both treatment and diagnosis of AD.

  5. Diminished glucose transport and phosphorylation in Alzheimer`s disease determined by dynamic FDG-PET

    SciTech Connect

    Piert, M.; Koeppe, R.A.; Giordani, B.; Berent, S.; Kuhl, D.E.

    1996-02-01

    Using dynamic [{sup 18}F] fluorodeoxyglucose (FDG) and PET, kinetic rate constants that describe influx (K{sub 1}) and efflux (k{sub 2}) of FDG as well s phosphorylation (k{sub 3}) and dephosphorylation (k{sub 4}) were determined in patients with probable Alzheimer`s disease and similarly aged normal controls. The regional cerebral metabolic rate for glucose (CMR{sub glu}) was calculated from individually fitted rate constants in frontal, temporal, parietal and occipital cerebral cortex, caudate nucleus, putamen, thalamus and cerebellar cortex. Dynamic PET scans were obtained in normal controls (n = 10, mean age = 67) and Alzheimer`s disease patients (n = 8, mean age = 67) for 60 min following injection of 10 mCi of FDG. The Alzheimer`s disease group was characterized by decreases of the CMR{sub glu} ranging from 13.3% in the frontal to 40.9% in the parietal cortex, which achieved significance in all regions except the thalamus. K{sub 1} was significantly reduced in the parietal (p < 0.01) and temporal cortices (p < 0.005), temporal and occipital cortex, and in the putamen and cerebellum (p < 0.05). The rate constants k{sub 2} and k{sub 4} were unchanged in the Alzheimer`s disease group. These data suggest that hypometabolism in Alzheimer`s disease is related to reduced glucose phosphorylation activity as well as diminished glucose transport, particularly in the most metabolically affected areas of the brain, the parietal and temporal cortex. 60 refs., 2 figs., 2 tabs.

  6. [On the 100th anniversary of Alzheimer's disease].

    PubMed

    Verhey, F R J

    2006-12-30

    In November 1906, the German neurologist Alois Alzheimer presented a lecture to his colleagues regarding a 55-year-old patient with dementia who was found to have aggregated protein deposits (senile plaques) and abnormal neurofibrils in the cerebral cortex. Alzheimer was born in 1864 in Bavaria. After he became financially independent through marriage, he could devote himself to neuropathological research. At the end of the 19th century, it was widely believed that dementia was the inevitable consequence of arteriosclerosis. Alzheimer questioned this belief after finding no postmortem evidence of arteriosclerotic vessel alterations in the brain of a young patient with dementia. After finding a second and third case, Alzheimer was convinced that he was on the verge of discovering a new disease. The eponym 'Alzheimer's disease' was introduced in 1910 by his mentor Kraepelin.

  7. The superficial white matter in Alzheimer's disease.

    PubMed

    Phillips, Owen R; Joshi, Shantanu H; Piras, Fabrizio; Orfei, Maria Donata; Iorio, Mariangela; Narr, Katherine L; Shattuck, David W; Caltagirone, Carlo; Spalletta, Gianfranco; Di Paola, Margherita

    2016-04-01

    White matter abnormalities have been shown in the large deep fibers of Alzheimer's disease patients. However, the late myelinating superficial white matter comprised of intracortical myelin and short-range association fibers has not received much attention. To investigate this area, we extracted a surface corresponding to the superficial white matter beneath the cortex and then applied a cortical pattern-matching approach which allowed us to register and subsequently sample diffusivity along thousands of points at the interface between the gray matter and white matter in 44 patients with Alzheimer's disease (Age: 71.02 ± 5.84, 16M/28F) and 47 healthy controls (Age 69.23 ± 4.45, 19M/28F). In patients we found an overall increase in the axial and radial diffusivity across most of the superficial white matter (P < 0.001) with increases in diffusivity of more than 20% in the bilateral parahippocampal regions and the temporal and frontal lobes. Furthermore, diffusivity correlated with the cognitive deficits measured by the Mini-Mental State Examination scores (P < 0.001). The superficial white matter has a unique microstructure and is critical for the integration of multimodal information during brain maturation and aging. Here we show that there are major abnormalities in patients and the deterioration of these fibers relates to clinical symptoms in Alzheimer's disease.

  8. Association of Alzheimer's disease and Chlamydophila pneumoniae.

    PubMed

    Stallings, Tiffany L

    2008-06-01

    This paper critically reviews the association of infection by Chlamydophila pneumoniae (C. pneumoniae) and Alzheimer's disease (AD). The aging population has increased interest in finding the cause of AD, but studies have yielded contradictory results that are likely due to varying diagnostic tools and different uses of diagnostic tests. Knowledge of AD's characteristics, risk factors, and hypothesized etiologies has expanded since Alois Alzheimer's initial description of AD. Epidemiologic and projection studies provide incidence estimates of AD through a two-stage method: (1) primary diagnosis of dementia by cognitive testing such as Mini-Mental State Examination (MMSE), and (2) clinical diagnosis of AD through criteria such as National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA). Cross-sectional studies yield prevalence estimates of infection by C. pneumoniae by detecting immunoglobulins through laboratory tests such as microimmunofluorescence (MIF). Studies examining the association of C. pneumoniae and AD are limited, but brain autopsy provides information about presence, proximity to areas associated with AD, and bacterial load. Standardization of diagnostic techniques would allow for better comparability of studies, but uncertainty about the best method of diagnosis of infection by C. pneumoniae and AD may call for revised or novel diagnostic tools.

  9. The superficial white matter in Alzheimer's disease.

    PubMed

    Phillips, Owen R; Joshi, Shantanu H; Piras, Fabrizio; Orfei, Maria Donata; Iorio, Mariangela; Narr, Katherine L; Shattuck, David W; Caltagirone, Carlo; Spalletta, Gianfranco; Di Paola, Margherita

    2016-04-01

    White matter abnormalities have been shown in the large deep fibers of Alzheimer's disease patients. However, the late myelinating superficial white matter comprised of intracortical myelin and short-range association fibers has not received much attention. To investigate this area, we extracted a surface corresponding to the superficial white matter beneath the cortex and then applied a cortical pattern-matching approach which allowed us to register and subsequently sample diffusivity along thousands of points at the interface between the gray matter and white matter in 44 patients with Alzheimer's disease (Age: 71.02 ± 5.84, 16M/28F) and 47 healthy controls (Age 69.23 ± 4.45, 19M/28F). In patients we found an overall increase in the axial and radial diffusivity across most of the superficial white matter (P < 0.001) with increases in diffusivity of more than 20% in the bilateral parahippocampal regions and the temporal and frontal lobes. Furthermore, diffusivity correlated with the cognitive deficits measured by the Mini-Mental State Examination scores (P < 0.001). The superficial white matter has a unique microstructure and is critical for the integration of multimodal information during brain maturation and aging. Here we show that there are major abnormalities in patients and the deterioration of these fibers relates to clinical symptoms in Alzheimer's disease. PMID:26801955

  10. Cardiorespiratory fitness is associated with brain structure, cognition, and mood in a middle-aged cohort at risk for Alzheimer's disease.

    PubMed

    Boots, Elizabeth A; Schultz, Stephanie A; Oh, Jennifer M; Larson, Jordan; Edwards, Dorothy; Cook, Dane; Koscik, Rebecca L; Dowling, Maritza N; Gallagher, Catherine L; Carlsson, Cynthia M; Rowley, Howard A; Bendlin, Barbara B; LaRue, Asenath; Asthana, Sanjay; Hermann, Bruce P; Sager, Mark A; Johnson, Sterling C; Okonkwo, Ozioma C

    2015-09-01

    Cardiorespiratory fitness (CRF) is an objective measure of habitual physical activity (PA), and has been linked to increased brain structure and cognition. The gold standard method for measuring CRF is graded exercise testing (GXT), but GXT is not feasible in many settings. The objective of this study was to examine whether a non-exercise estimate of CRF is related to gray matter (GM) volumes, white matter hyperintensities (WMH), cognition, objective and subjective memory function, and mood in a middle-aged cohort at risk for Alzheimer's disease (AD). Three hundred and fifteen cognitively healthy adults (mean age =58.58 years) enrolled in the Wisconsin Registry for Alzheimer's Prevention underwent structural MRI scanning, cognitive testing, anthropometric assessment, venipuncture for laboratory tests, and completed a self-reported PA questionnaire. A subset (n = 85) underwent maximal GXT. CRF was estimated using a previously validated equation incorporating sex, age, body-mass index, resting heart rate, and self-reported PA. Results indicated that the CRF estimate was significantly associated with GXT-derived peak oxygen consumption, validating its use as a non-exercise CRF measure in our sample. Support for this finding was seen in significant associations between the CRF estimate and several cardiovascular risk factors. Higher CRF was associated with greater GM volumes in several AD-relevant brain regions including the hippocampus, amygdala, precuneus, supramarginal gyrus, and rostral middle frontal gyrus. Increased CRF was also associated with lower WMH and better cognitive performance in Verbal Learning & Memory, Speed & Flexibility, and Visuospatial Ability. Lastly, CRF was negatively correlated with self- and informant-reported memory complaints, and depressive symptoms. Together, these findings suggest that habitual participation in physical activity may provide protection for brain structure and cognitive function, thereby decreasing future risk for AD.

  11. Detection of Amyloid β Signature in the Lens and Its Correlation in the Brain to Aid in the Diagnosis of Alzheimer's Disease.

    PubMed

    Kerbage, Charles; Sadowsky, Carl H; Tariot, Pierre N; Agronin, Marc; Alva, Gustavo; Turner, F Darell; Nilan, Dennis; Cameron, Anne; Cagle, Gerald D; Hartung, Paul D

    2015-12-01

    We report the findings from a clinical trial in which a group of patients clinically diagnosed with probable Alzheimer's disease (AD) were discriminated from an age-matched group of healthy volunteers (HVs) with statistical significance (P<.001). The results from 20 patients with AD and 20 HVs were obtained by a Fluorescent Ligand Eye Scanning (FLES) technique that measures a fluorescent signature specific to an exogenous ligand bound to amyloid-β in the lens of the eye. Sensitivity and specificity of 85% and 95%, respectively, have been achieved in predicting clinical diagnosis. Additionally, amyloid brain imaging using florbetapir F18 positron emission tomography shows significant correlation with the results obtained in the eye. Results of the study demonstrate the safety of the FLES system.

  12. Cognitive rehabilitation in Alzheimer's Disease.

    PubMed

    Cotelli, Maria; Calabria, Marco; Zanetti, Orazio

    2006-04-01

    Non-pharmacological treatment in Alzheimer's Disease has gained great attention in recent years. The limited efficacy of drug therapy and the plasticity of human central nervous system are the two main reasons that explain this growing interest in rehabilitation. Different approaches have been developed. Here we discuss the efficacy of non-pharmacological therapy in the frame of two main approaches: Multistrategy Approaches (Reality Orientation, Reminiscence Therapy and Validation Therapy) and Cognitive Methods.

  13. Midlife predictors of Alzheimer's disease

    PubMed Central

    Bendlin, B. B.; Carlsson, C. M.; Gleason, C. E.; Johnson, S. C.; Sodhi, A.; Gallagher, C.L.; Puglielli, L.; Engelman, C. D.; Ries, M. L.; Xu, G.; Wharton, W.; Asthana, S.

    2010-01-01

    Factors contributing to increased risk for Alzheimer's disease (AD) include age, sex, genes, and family history of AD. Several risk factors for AD are endogenous; however accumulating evidence implicates modifiable risk factors in the pathogenesis of AD. Although the continued task of identifying new genes will be critical to learning more about the disease, several research findings suggest that potentially alterable environmental factors influence genetic contributions, providing targets for disease prevention and treatment. Here, we review midlife risk factors for AD, and address the potential for therapeutic intervention in midlife. PMID:20044221

  14. Rho-associated protein kinase 1 (ROCK1) is increased in Alzheimer's disease and ROCK1 depletion reduces amyloid-β levels in brain.

    PubMed

    Henderson, Benjamin W; Gentry, Erik G; Rush, Travis; Troncoso, Juan C; Thambisetty, Madhav; Montine, Thomas J; Herskowitz, Jeremy H

    2016-08-01

    Alzheimer's disease (AD) is the leading cause of dementia and mitigating amyloid-β (Aβ) levels may serve as a rational therapeutic avenue to slow AD progression. Pharmacologic inhibition of the Rho-associated protein kinases (ROCK1 and ROCK2) is proposed to curb Aβ levels, and mechanisms that underlie ROCK2's effects on Aβ production are defined. How ROCK1 affects Aβ generation remains a critical barrier. Here, we report that ROCK1 protein levels were elevated in mild cognitive impairment due to AD (MCI) and AD brains compared to controls. Aβ42 oligomers marginally increased ROCK1 and ROCK2 protein levels in neurons but strongly induced phosphorylation of Lim kinase 1 (LIMK1), suggesting that Aβ42 activates ROCKs. RNAi depletion of ROCK1 or ROCK2 suppressed endogenous Aβ40 production in neurons, and Aβ40 levels were reduced in brains of ROCK1 heterozygous knock-out mice compared to wild-type littermate controls. ROCK1 knockdown decreased amyloid precursor protein (APP), and treatment with bafilomycin accumulated APP levels in neurons depleted of ROCK1. These observations suggest that reduction of ROCK1 diminishes Aβ levels by enhancing APP protein degradation. Collectively, these findings support the hypothesis that both ROCK1 and ROCK2 are therapeutic targets to combat Aβ production in AD. Mitigating amyloid-β (Aβ) levels is a rational strategy for Alzheimer's disease (AD) treatment, however, therapeutic targets with clinically available drugs are lacking. We hypothesize that Aβ accumulation in mild cognitive impairment because of AD (MCI) and AD activates the RhoA/ROCK pathway which in turn fuels production of Aβ. Escalation of this cycle over the course of many years may contribute to the buildup of amyloid pathology in MCI and/or AD. PMID:27246255

  15. Rho-associated protein kinase 1 (ROCK1) is increased in Alzheimer's disease and ROCK1 depletion reduces amyloid-β levels in brain.

    PubMed

    Henderson, Benjamin W; Gentry, Erik G; Rush, Travis; Troncoso, Juan C; Thambisetty, Madhav; Montine, Thomas J; Herskowitz, Jeremy H

    2016-08-01

    Alzheimer's disease (AD) is the leading cause of dementia and mitigating amyloid-β (Aβ) levels may serve as a rational therapeutic avenue to slow AD progression. Pharmacologic inhibition of the Rho-associated protein kinases (ROCK1 and ROCK2) is proposed to curb Aβ levels, and mechanisms that underlie ROCK2's effects on Aβ production are defined. How ROCK1 affects Aβ generation remains a critical barrier. Here, we report that ROCK1 protein levels were elevated in mild cognitive impairment due to AD (MCI) and AD brains compared to controls. Aβ42 oligomers marginally increased ROCK1 and ROCK2 protein levels in neurons but strongly induced phosphorylation of Lim kinase 1 (LIMK1), suggesting that Aβ42 activates ROCKs. RNAi depletion of ROCK1 or ROCK2 suppressed endogenous Aβ40 production in neurons, and Aβ40 levels were reduced in brains of ROCK1 heterozygous knock-out mice compared to wild-type littermate controls. ROCK1 knockdown decreased amyloid precursor protein (APP), and treatment with bafilomycin accumulated APP levels in neurons depleted of ROCK1. These observations suggest that reduction of ROCK1 diminishes Aβ levels by enhancing APP protein degradation. Collectively, these findings support the hypothesis that both ROCK1 and ROCK2 are therapeutic targets to combat Aβ production in AD. Mitigating amyloid-β (Aβ) levels is a rational strategy for Alzheimer's disease (AD) treatment, however, therapeutic targets with clinically available drugs are lacking. We hypothesize that Aβ accumulation in mild cognitive impairment because of AD (MCI) and AD activates the RhoA/ROCK pathway which in turn fuels production of Aβ. Escalation of this cycle over the course of many years may contribute to the buildup of amyloid pathology in MCI and/or AD.

  16. Association studies in late onset sporadic Alzheimer`s disease

    SciTech Connect

    Goate, A.M.; Lendon, C.; Talbot, C.

    1994-09-01

    Alzheimer`s disease (AD) is characterized by an adult onset progressive dementia and the presence of numerous plaques and tangles within the brain at autopsy. The senile plaques are composed of a proteinaceous core surrounded by dystrophic neurites. The major protein component of the core is {beta}-amyloid but antibodies to many other proteins bind to senile plaques, e.g., antibodies to apolioprotein E (ApoE) and to {alpha}1-antichymotrypsin (AACT). Genetic studies have implicated mutations within the {beta}-amyloid precursor protein gene as the cause of AD in a small number of early onset AD families. More recently, assocition studies in late onset AD have demonstrated a positive association between ApoE-{epsilon}4 and AD. We report evidence for a negative association between ApoE-{epsilon}2 and AD in a large sample of sporadic late onset AD cases and matched controls supporting the role of ApoE in the etiology of AD. Ninety-three patients with sporadic AD (average age = 75 years, s.d. 8 yrs.) and 67 normal controls from the same ethnic background (age = 77 yrs., s.d. 10 yrs.) were recruited through the patient registry of the Washington University Alzheimer`s Disease Research Center. We found a statistically significant increase in ApoE-{epsilon}4 allele frequency in patients compared with controls ({chi}{sup 2}=7.75, 1 d.f., one tailed p=0.0027) and a significant decrease in {epsilon}2 allele frequency (Fisher`s exact test, one tailed p=0.0048), whereas the decreased frequency of {epsilon}3 in the patient groups was not statistically significant. Allele {epsilon}2 conferred a strong protective effect in our sample, with the odds ratio for AD for subjects possessing this allele being 0.08 (85% confidence interval 0.01-0.69). Similar studies using a polymorphism within the AACT gene showed no association with alleles at this locus in the entire AD sample or in AD cases homozygous for ApoE-{epsilon}3.

  17. Treatment of Alzheimer Disease With CT Scans

    PubMed Central

    Moore, Eugene R.; Hosfeld, Victor D.; Nadolski, David L.

    2016-01-01

    Alzheimer disease (AD) primarily affects older adults. This neurodegenerative disorder is the most common cause of dementia and is a leading source of their morbidity and mortality. Patient care costs in the United States are about 200 billion dollars and will more than double by 2040. This case report describes the remarkable improvement in a patient with advanced AD in hospice who received 5 computed tomography scans of the brain, about 40 mGy each, over a period of 3 months. The mechanism appears to be radiation-induced upregulation of the patient’s adaptive protection systems against AD, which partially restored cognition, memory, speech, movement, and appetite. PMID:27103883

  18. Effect of trichostatin A on gelsolin levels, proteolysis of amyloid precursor protein, and amyloid beta-protein load in the brain of transgenic mouse model of Alzheimer's disease.

    PubMed

    Yang, Wenzhong; Chauhan, Abha; Wegiel, Jerzy; Kuchna, Izabela; Gu, Feng; Chauhan, Ved

    2014-01-01

    In vivo and in vitro studies have shown that gelsolin is an anti-amyloidogenic protein. Trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, promotes the expression of gelsolin. Fibrillized amyoid beta-protein (Aβ) is a key constituent of amyloid plaques in the brains of patients with Alzheimer's disease (AD). We studied the effects of TSA on the levels of gelsolin; amyloid precursor protein (APP); proteolytic enzymes (γ-secretase and β-secretase) responsible for the production of Aβ; Aβ-cleaving enzymes, i.e., neprilysin (NEP) and insulin-degrading enzyme (IDE); and amyloid load in the double transgenic (Tg) APPswe/PS1(δE9) mouse model of AD. Intraperitoneal injection of TSA for two months (9-11 months of age) resulted in decreased activity of HDAC, and increased levels of gelsolin in the hippocampus and cortex of the brain in AD Tg mice as compared to vehicle-treated mice. TSA also increased the levels of γ-secretase and β-secretase activity in the brain. However, TSA did not show any effect on the activities or the expression levels of NEP and IDE in the brain. Furthermore, TSA treatment of AD Tg mice showed no change in the amyloid load (percent of examined area occupied by amyloid plaques) in the hippocampus and cortex, suggesting that TSA treatment did not result in the reduction of amyloid load. Interestingly, TSA prevented the formation of new amyloid deposits but increased the size of existing plaques. TSA treatment did not cause any apoptosis in the brain. These results suggest that TSA increases gelsolin expression in the brain, but the pleiotropic effects of TSA negate the anti-amyloidogenic effect of gelsolin in AD Tg mice.

  19. The Role of Mast Cells in Alzheimer's Disease.

    PubMed

    Shaik-Dasthagirisaheb, Yasdani B; Conti, Pio

    2016-01-01

    Immunity and inflammation are deeply involved in Alzheimer's disease. The most important properties of pathological Alzheimer's disease are the extracellular deposits of amyloid â-protein plaque aggregates along with other unknown mutated proteins, which are implicated in immunity and inflammation. Mast cells are found in the brain of all mammalian species and in the periphery, and their biological mediators, including cytokines/chemokines, arachidonic acid products and stored enzymes, play an import role in Alzheimer's disease. Cytokines/chemokines, which are generated mostly by microglia and astrocytes in Alzheimer's disease, contribute to nearly every aspect of neuroinflammation and amyloid â-protein plaque aggregates may induce in mast cells the release of a plethora of mediators, including pro-inflammatory cytokines/chemokines such as interleukin-1, interleukin-6, interleukin-8, interleukin-10, tumor necrosis factor-alpha, vascular endothelial growth factor, transforming growth factor beta, CXCL8 and CCL2-3-4. These proinflammatory cytokines/chemokines are prominent mediators of neuroinflammation in brain disorders such as Alzheimer's disease, and their inhibition may be associated with improved recovery. In this review, we summarize the current knowledge regarding the roles of mast cell mediators (stored and de novo synthesis) in the pathogenesis of Alzheimer's disease. PMID:27629855

  20. The Role of Mast Cells in Alzheimer's Disease.

    PubMed

    Shaik-Dasthagirisaheb, Yasdani B; Conti, Pio

    2016-01-01

    Immunity and inflammation are deeply involved in Alzheimer's disease. The most important properties of pathological Alzheimer's disease are the extracellular deposits of amyloid â-protein plaque aggregates along with other unknown mutated proteins, which are implicated in immunity and inflammation. Mast cells are found in the brain of all mammalian species and in the periphery, and their biological mediators, including cytokines/chemokines, arachidonic acid products and stored enzymes, play an import role in Alzheimer's disease. Cytokines/chemokines, which are generated mostly by microglia and astrocytes in Alzheimer's disease, contribute to nearly every aspect of neuroinflammation and amyloid â-protein plaque aggregates may induce in mast cells the release of a plethora of mediators, including pro-inflammatory cytokines/chemokines such as interleukin-1, interleukin-6, interleukin-8, interleukin-10, tumor necrosis factor-alpha, vascular endothelial growth factor, transforming growth factor beta, CXCL8 and CCL2-3-4. These proinflammatory cytokines/chemokines are prominent mediators of neuroinflammation in brain disorders such as Alzheimer's disease, and their inhibition may be associated with improved recovery. In this review, we summarize the current knowledge regarding the roles of mast cell mediators (stored and de novo synthesis) in the pathogenesis of Alzheimer's disease.

  1. Progress Report on Alzheimer Disease: Volume III.

    ERIC Educational Resources Information Center

    National Inst. on Aging (DHHS/PHS), Bethesda, MD.

    This report summarizes advances in the understanding of Alzheimer's disease, the major cause of mental disability among older Americans. The demography of the disease is discussed, noting that approximately 2.5 million American adults are afflicted with the disease and that the large increase in the number of Alzheimer's disease patients is due to…

  2. Changes in chromatin structure associated with Alzheimer's disease.

    PubMed

    Lewis, P N; Lukiw, W J; De Boni, U; McLachlan, D R

    1981-11-01

    The enzyme micrococcal nuclease was used to examine the accessibility of chromatin extracted from brains of 13 patients with senile and presenile dementia of the Alzheimer type. Compared with chromatin extracted from brains of 8 patients without neurological signs or brain pathology and brains of 7 patients with nonAlzheimer dementia, Alzheimer chromatin was less accessible to this enzyme. Reduced accessibility was reflected by a reduced yield of mononucleosomes in comparison with dinucleosomes and larger oligomers. Both neuronal and glial chromatin were found to be similarly affected. The reduced yield of mononucleosomes from Alzheimer chromatin is not due to their increased breakdown, but is probably related to protein associated with the internucleosomal linker region that retards nuclease action. Dinucleosomes isolated from control and Alzheimer nuclease digests were examined for their protein complement. Three perchloric acid-soluble proteins situated in the histone H1 region of sodium dodecyl sulfate (SDS) gels were present in elevated levels in Alzheimer dinucleosomes. These results represent the first example of altered chromosomal proteins associated with a diseased state of the brain.

  3. Alzheimer's Disease Facts and Figures

    MedlinePlus

    ... prevented, cured or even slowed. Invest in a world without Alzheimer's. Donate Caregivers In 2015, 15.9 ... Association ® . All rights reserved. Our vision is a world without Alzheimer's Formed in 1980, the Alzheimer's Association ...

  4. Commentary: is Alzheimer's disease uniquely human?

    PubMed Central

    Finch, Caleb E.; Austad, Steven N.

    2015-01-01

    That Alzheimer's disease (AD) might be a human-specific disease was hypothesized by Rapoport in 1989. Apes and humans share an identical amyloid beta (Aβ) peptide amino acid sequence and accumulate considerable Aβ deposits after age 40 years, an age when amyloid plaques are uncommon in humans. Despite their early Aβ buildup, ape brains have not shown evidence dystrophic neurites near plaques. Aging great ape brains also have few neurofibrillary tangles, with one exception of 1 obese chimpanzee euthanized after a stroke who displayed abundant neurofibrillary tangles, but without the typical AD distribution. We discuss the need for more exacting evaluation of neuron density with age, and note husbandry issues that may allow great apes to live to greater ages. We remain reserved about expectations for fully developed AD-like pathology in the great apes of advanced ages and cautiously support Rapoport's hypothesis. PMID:25533426

  5. Amyloid beta peptide immunotherapy in Alzheimer disease.

    PubMed

    Delrieu, J; Ousset, P J; Voisin, T; Vellas, B

    2014-12-01

    Recent advances in the understanding of Alzheimer's disease pathogenesis have led to the development of numerous compounds that might modify the disease process. Amyloid β peptide represents an important molecular target for intervention in Alzheimer's disease. The main purpose of this work is to review immunotherapy studies in relation to the Alzheimer's disease. Several types of amyloid β peptide immunotherapy for Alzheimer's disease are under investigation, active immunization and passive administration with monoclonal antibodies directed against amyloid β peptide. Although immunotherapy approaches resulted in clearance of amyloid plaques in patients with Alzheimer's disease, this clearance did not show significant cognitive effect for the moment. Currently, several amyloid β peptide immunotherapy approaches are under investigation but also against tau pathology. Results from amyloid-based immunotherapy studies in clinical trials indicate that intervention appears to be more effective in early stages of amyloid accumulation in particular solanezumab with a potential impact at mild Alzheimer's disease, highlighting the importance of diagnosing Alzheimer's disease as early as possible and undertaking clinical trials at this stage. In both phase III solanezumab and bapineuzumab trials, PET imaging revealed that about a quarter of patients lacked fibrillar amyloid pathology at baseline, suggesting that they did not have Alzheimer's disease in the first place. So a new third phase 3 clinical trial for solanezumab, called Expedition 3, in patients with mild Alzheimer's disease and evidence of amyloid burden has been started. Thus, currently, amyloid intervention is realized at early stage of the Alzheimer's disease in clinical trials, at prodromal Alzheimer's disease, or at asymptomatic subjects or at risk to develop Alzheimer's disease and or at asymptomatic subjects with autosomal dominant mutation.

  6. Precocious Alterations of Brain Oscillatory Activity in Alzheimer's Disease: A Window of Opportunity for Early Diagnosis and Treatment.

    PubMed

    Hamm, Valentine; Héraud, Céline; Cassel, Jean-Christophe; Mathis, Chantal; Goutagny, Romain

    2015-01-01

    Alzheimer's disease (AD) is the most common form of neurodegenerative dementia accounting for 50-80% of all age-related dementia. This pathology is characterized by the progressive and irreversible alteration of cognitive functions, such as memory, leading inexorably to the loss of autonomy for patients with AD. The pathology is linked with aging and occurs most commonly around 65 years old. Its prevalence (5% over 65 years of age and 20% after 80 years) constitutes an economic and social burden for AD patients and their family. At the present, there is still no cure for AD, actual treatments being moderately effective only in early stages of the pathology. A lot of efforts have been deployed with the aim of defining new AD biomarkers. Successful early detection of mild cognitive impairment (MCI) linked to AD requires the identification of biomarkers capable of distinguishing individuals with early stages of AD from other pathologies impacting cognition such as depression. In this article, we will review recent evidence suggesting that electroencephalographic (EEG) recordings, coupled with behavioral assessments, could be a useful approach and easily implementable for a precocious detection of AD.

  7. Regional flux analysis for discovering and quantifying anatomical changes: An application to the brain morphometry in Alzheimer's disease.

    PubMed

    Lorenzi, M; Ayache, N; Pennec, X

    2015-07-15

    In this study we introduce the regional flux analysis, a novel approach to deformation based morphometry based on the Helmholtz decomposition of deformations parameterized by stationary velocity fields. We use the scalar pressure map associated to the irrotational component of the deformation to discover the critical regions of volume change. These regions are used to consistently quantify the associated measure of volume change by the probabilistic integration of the flux of the longitudinal deformations across the boundaries. The presented framework unifies voxel-based and regional approaches, and robustly describes the volume changes at both group-wise and subject-specific level as a spatial process governed by consistently defined regions. Our experiments on the large cohorts of the ADNI dataset show that the regional flux analysis is a powerful and flexible instrument for the study of Alzheimer's disease in a wide range of scenarios: cross-sectional deformation based morphometry, longitudinal discovery and quantification of group-wise volume changes, and statistically powered and robust quantification of hippocampal and ventricular atrophy.

  8. Regional flux analysis for discovering and quantifying anatomical changes: An application to the brain morphometry in Alzheimer's disease.

    PubMed

    Lorenzi, M; Ayache, N; Pennec, X

    2015-07-15

    In this study we introduce the regional flux analysis, a novel approach to deformation based morphometry based on the Helmholtz decomposition of deformations parameterized by stationary velocity fields. We use the scalar pressure map associated to the irrotational component of the deformation to discover the critical regions of volume change. These regions are used to consistently quantify the associated measure of volume change by the probabilistic integration of the flux of the longitudinal deformations across the boundaries. The presented framework unifies voxel-based and regional approaches, and robustly describes the volume changes at both group-wise and subject-specific level as a spatial process governed by consistently defined regions. Our experiments on the large cohorts of the ADNI dataset show that the regional flux analysis is a powerful and flexible instrument for the study of Alzheimer's disease in a wide range of scenarios: cross-sectional deformation based morphometry, longitudinal discovery and quantification of group-wise volume changes, and statistically powered and robust quantification of hippocampal and ventricular atrophy. PMID:25963734

  9. Therapeutic perspectives in Alzheimer's disease.

    PubMed

    Tschäpe, Jakob-A; Hartmann, Tobias

    2006-01-01

    It is now almost a century ago that Alois Alzheimer first presented his results in public. Main characteristics of Alzheimer's disease (AD) are massive cerebral accumulation of amyloid, composed of fibrillary aggregates of the Amyloid beta peptide (Abeta) and intracellular accumulation of abnormally phosphorylated tau protein associated with widespread neurodegeneration. The clinical picture is characterized by progressive and irreversible dementia, which is eventually fatal. To date, there is no cure for this severe disease affecting more than of 30 million individuals worldwide. In the last decades, the treatment of Alzheimer patients was mainly focusing on symptomatical strategies. Based on the augmented knowledge about the mechanisms underlying the pathology of AD, particularly the molecular causes and consequences of AD, different therapeutic approaches arose and recently, treatment with Statins, NSAIDs and Abeta vaccines reached the level of clinical trials, showing some indication of efficacy already. According to actual evaluations, these approaches have realistic chances to become established as therapeutic routine in AD within the next 10 years. We will review here some of the most promising novel approaches to cure and prevent rather than to treat the symptoms of AD.

  10. The behavioural/dysexecutive variant of Alzheimer's disease: clinical, neuroimaging and pathological features.

    PubMed

    Ossenkoppele, Rik; Pijnenburg, Yolande A L; Perry, David C; Cohn-Sheehy, Brendan I; Scheltens, Nienke M E; Vogel, Jacob W; Kramer, Joel H; van der Vlies, Annelies E; La Joie, Renaud; Rosen, Howard J; van der Flier, Wiesje M; Grinberg, Lea T; Rozemuller, Annemieke J; Huang, Eric J; van Berckel, Bart N M; Miller, Bruce L; Barkhof, Frederik; Jagust, William J; Scheltens, Philip; Seeley, William W; Rabinovici, Gil D

    2015-09-01

    A 'frontal variant of Alzheimer's disease' has been described in patients with predominant behavioural or dysexecutive deficits caused by Alzheimer's disease pathology. The description of this rare Alzheimer's disease phenotype has been limited to case reports and small series, and many clinical, neuroimaging and neuropathological characteristics are not well understood. In this retrospective study, we included 55 patients with Alzheimer's disease with a behavioural-predominant presentation (behavioural Alzheimer's disease) and a neuropathological diagnosis of high-likelihood Alzheimer's disease (n = 17) and/or biomarker evidence of Alzheimer's disease pathology (n = 44). In addition, we included 29 patients with autopsy/biomarker-defined Alzheimer's disease with a dysexecutive-predominant syndrome (dysexecutive Alzheimer's disease). We performed structured chart reviews to ascertain clinical features. First symptoms were more often cognitive (behavioural Alzheimer's disease: 53%; dysexecutive Alzheimer's disease: 83%) than behavioural (behavioural Alzheimer's disease: 25%; dysexecutive Alzheimer's disease: 3%). Apathy was the most common behavioural feature, while hyperorality and perseverative/compulsive behaviours were less prevalent. Fifty-two per cent of patients with behavioural Alzheimer's disease met diagnostic criteria for possible behavioural-variant frontotemporal dementia. Overlap between behavioural and dysexecutive Alzheimer's disease was modest (9/75 patients). Sixty per cent of patients with behavioural Alzheimer's disease and 40% of those with the dysexecutive syndrome carried at least one APOE ε4 allele. We also compared neuropsychological test performance and brain atrophy (applying voxel-based morphometry) with matched autopsy/biomarker-defined typical (amnestic-predominant) Alzheimer's disease (typical Alzheimer's disease, n = 58), autopsy-confirmed/Alzheimer's disease biomarker-negative behavioural variant frontotemporal dementia (n = 59

  11. Advances in Raman spectroscopy for the diagnosis of Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Sudworth, Caroline D.; Archer, John K. J.; Black, Richard A.; Mann, David

    2006-02-01

    Within the next 50 years Alzheimer's disease is expected to affect 100 million people worldwide. The progressive decline in the mental health of the patient is caused by severe brain atrophy generated by the breakdown and aggregation of proteins, resulting in β-amyloid plaques and neurofibrillary tangles. The greatest challenge to Alzheimer's disease lies in the pursuit of an early and definitive diagnosis, in order that suitable treatment can be administered. At the present time, definitive diagnosis is restricted to post-mortem examination. Alzheimer's disease also remains without a long-term cure. This research demonstrates the potential role of Raman spectroscopy, combined with principle components analysis (PCA), as a diagnostic method. Analyses of ethically approved ex vivo post-mortem brain tissues (originating from frontal and occipital lobes) from control (3 normal elderly subjects and 3 Huntingdon's disease subjects) and Alzheimer's disease (12 subjects) brain sections, and a further set of 12 blinded samples are presented. Spectra originating from these tissues are highly reproducible, and initial results indicate a vital difference in protein content and conformation, relating to the abnormally high levels of aggregated proteins in the diseased tissues. Further examination of these spectra using PCA allows for the separation of control from diseased tissues. The validation of the PCA models using blinded samples also displays promise for the identification of Alzheimer's disease, in conjunction with secondary information regarding other brain diseases and dementias. These results provide a route for Raman spectroscopy as a possible non-invasive, non-destructive tool for the early diagnosis of Alzheimer's disease.

  12. [Advances in the researches of lutein and alzheimer's disease].

    PubMed

    Xu, Xianrong; Lin, Xiaoming

    2015-05-01

    Lutein, a kind of oxycarotenoid, can pass the blood brain barrier and preferentially accumulate in the human brain, which is the most abundant carotenoid in human brain. Evidence from multiple studies suggested that lutein was closely related to age-related cognitive decline and risk of Alzheimer's disease (AD) in human. Dietary, plasma and brain concentrations of lutein were negatively associated with age-related cognitive decline. Lutein concentrations in plasma and brain were significantly lower in AD patients than those of health control. In human brain, lutein was the sole carotenoid which consistently associated with a range of cognitive function measures. In elderly women, lutein supplement can improve the cognitive function. In this article, we systematically reviewed the literature on the role of lutein in age-related cognitive decline and alzheimer's disease and its possible mechanisms. It may prove some benefit information for the advanced research and prevention of AD.

  13. A novel blood-brain barrier co-culture system for drug targeting of Alzheimer's disease: establishment by using acitretin as a model drug.

    PubMed

    Freese, Christian; Reinhardt, Sven; Hefner, Gudrun; Unger, Ronald E; Kirkpatrick, C James; Endres, Kristina

    2014-01-01

    In the pathogenesis of Alzheimer's disease (AD) the homeostasis of amyloid precursor protein (APP) processing in the brain is impaired. The expression of the competing proteases ADAM10 (a disintegrin and metalloproteinase 10) and BACE-1 (beta site APP cleaving enzyme 1) is shifted in favor of the A-beta generating enzyme BACE-1. Acitretin--a synthetic retinoid-e.g., has been shown to increase ADAM10 gene expression, resulting in a decreased level of A-beta peptides within the brain of AD model mice and thus is of possible value for AD therapy. A striking challenge in evaluating novel therapeutically applicable drugs is the analysis of their potential to overcome the blood-brain barrier (BBB) for central nervous system targeting. In this study, we established a novel cell-based bio-assay model to test ADAM10-inducing drugs for their ability to cross the BBB. We therefore used primary porcine brain endothelial cells (PBECs) and human neuroblastoma cells (SH-SY5Y) transfected with an ADAM10-promoter luciferase reporter vector in an indirect co-culture system. Acitretin served as a model substance that crosses the BBB and induces ADAM10 expression. We ensured that ADAM10-dependent constitutive APP metabolism in the neuronal cells was unaffected under co-cultivation conditions. Barrier properties established by PBECs were augmented by co-cultivation with SH-SY5Y cells and they remained stable during the treatment with acitretin as demonstrated by electrical resistance measurement and permeability-coefficient determination. As a consequence of transcellular acitretin transport measured by HPLC, the activity of the ADAM10-promoter reporter gene was significantly increased in co-cultured neuronal cells as compared to vehicle-treated controls. In the present study, we provide a new bio-assay system relevant for the study of drug targeting of AD. This bio-assay can easily be adapted to analyze other Alzheimer- or CNS disease-relevant targets in neuronal cells, as their

  14. A novel blood-brain barrier co-culture system for drug targeting of Alzheimer's disease: establishment by using acitretin as a model drug.

    PubMed

    Freese, Christian; Reinhardt, Sven; Hefner, Gudrun; Unger, Ronald E; Kirkpatrick, C James; Endres, Kristina

    2014-01-01

    In the pathogenesis of Alzheimer's disease (AD) the homeostasis of amyloid precursor protein (APP) processing in the brain is impaired. The expression of the competing proteases ADAM10 (a disintegrin and metalloproteinase 10) and BACE-1 (beta site APP cleaving enzyme 1) is shifted in favor of the A-beta generating enzyme BACE-1. Acitretin--a synthetic retinoid-e.g., has been shown to increase ADAM10 gene expression, resulting in a decreased level of A-beta peptides within the brain of AD model mice and thus is of possible value for AD therapy. A striking challenge in evaluating novel therapeutically applicable drugs is the analysis of their potential to overcome the blood-brain barrier (BBB) for central nervous system targeting. In this study, we established a novel cell-based bio-assay model to test ADAM10-inducing drugs for their ability to cross the BBB. We therefore used primary porcine brain endothelial cells (PBECs) and human neuroblastoma cells (SH-SY5Y) transfected with an ADAM10-promoter luciferase reporter vector in an indirect co-culture system. Acitretin served as a model substance that crosses the BBB and induces ADAM10 expression. We ensured that ADAM10-dependent constitutive APP metabolism in the neuronal cells was unaffected under co-cultivation conditions. Barrier properties established by PBECs were augmented by co-cultivation with SH-SY5Y cells and they remained stable during the treatment with acitretin as demonstrated by electrical resistance measurement and permeability-coefficient determination. As a consequence of transcellular acitretin transport measured by HPLC, the activity of the ADAM10-promoter reporter gene was significantly increased in co-cultured neuronal cells as compared to vehicle-treated controls. In the present study, we provide a new bio-assay system relevant for the study of drug targeting of AD. This bio-assay can easily be adapted to analyze other Alzheimer- or CNS disease-relevant targets in neuronal cells, as their

  15. Brain lesions comprised of aluminum-rich cells that lack microtubules may be associated with the cognitive deficit of Alzheimer's disease.

    PubMed

    Walton, J R

    2009-11-01

    A recent longitudinal study described an inducible rodent model for age-related cognitive deterioration. This model was produced by chronically feeding rats aluminum, from age 12 months onwards, in measured amounts equivalent to total aluminum levels ingested by Americans from their food, beverages and aluminum additives. The rats performed a hippocampal-dependent spatial memory discrimination task weekly throughout middle age and old age. One-third of the rats attained significantly lower mean performance scores in old age than middle age, in an aluminum dose-dependent manner, and exhibited behavioral signs observed in dementia. The present study used histological and immunohistochemical techniques to identify neuropathological difference between brains of rats that showed cognitive deterioration and the cognitively intact controls. Most aged rat brains had large numbers of aluminum-loaded pyramidal cells in their entorhinal cortex and temporal association cortex but the cognitively deteriorated rats had threefold more such cells than controls (p<0.01). A distinguishing feature was that all brains of the cognitively deteriorated rats, and none of controls, had at least one substantial hippocampal lesion that consisted of aluminum-rich microtubule-depleted pyramidal cells with shriveled processes, and loss of synapse density. Corticolimbic sections from brains of humans with Alzheimer's disease also showed neuropathology consistent with this type of damage. The evidence suggests bioavailable aluminum gradually accumulates in cortical and limbic regions of susceptible subjects' brains, eventually producing hippocampal lesions consisting of dysfunctional aluminum-rich microtubule-depleted pyramidal cells with damaged neurites and synapse loss. These lesions expand over time, disrupting afferent and efferent hippocampal circuitry with the development of clinically overt dementia.

  16. [Clinical symptoms of Alzheimer disease].

    PubMed

    Tariska, P; Urbanics, K; Knolmayer, J; Mészáros, A

    1995-04-23

    Data of patients suffering from Alzheimer's disease and checked out in the special unit named Memory Clinic functioning from 1992 in the National Institute of Psychiatry and Neurology are summarized. Age average of the 60 patients was 63 years, the first symptoms of the disease had appeared in 57 p.c. before the age of 65, so the classical presenile form of the ailment is represented too in the material. Predominance of multifocal cortical function disturbances in the symptomatology is characteristic, association of the depression is outstandingly frequent. The atypical features, or those characteristic in diseases of cerebrovascular origin are not infrequently seen (headache, dizziness, slight symptoms of pyramidal lesions). The absence of epileptic seizures It was interesting even in considering the data of the literature too. The main points of clinical diagnostics and differential diagnostics are demonstrated with the aid of case reports. The author's material is the first Hungarian publication in the topics of clinical symptoms of patients suffering from Alzheimer's disease that had been investigated with up-to-date methods. Occurrence of the disease of very great frequency could be supposed to occur at general practitioners, the importance of differential diagnostics and planning of the complex longlasting therapy is extremely great.

  17. Pharmacotherapeutic targets in Alzheimer's disease

    PubMed Central

    Biran, Yif'at; Masters, Colin L; Barnham, Kevin J; Bush, Ashley I; Adlard, Paul A

    2009-01-01

    Abstract Alzheimer's disease (AD) is a progressive neurodegenerative disorder which is characterized by an increasing impairment in normal memory and cognitive processes that significantly diminishes a person's daily functioning. Despite decades of research and advances in our understanding of disease aetiology and pathogenesis, there are still no effective disease-modifying drugs available for the treatment of AD. However, numerous compounds are currently undergoing pre-clinical and clinical evaluations. These candidate pharma-cotherapeutics are aimed at various aspects of the disease, such as the microtubule-associated τ-protein, the amyloid-β (Aβ) peptide and metal ion dyshomeostasis – all of which are involved in the development and progression of AD. We will review the way these pharmacological strategies target the biochemical and clinical features of the disease and the investigational drugs for each category. PMID:19040415

  18. Alzheimer's disease: new diagnostic and therapeutic tools.

    PubMed

    Racchi, Marco; Uberti, Daniela; Govoni, Stefano; Memo, Maurizio; Lanni, Cristina; Vasto, Sonya; Candore, Giuseppina; Caruso, Calogero; Romeo, Loriana; Scapagnini, Giovanni

    2008-08-13

    On March 19, 2008 a Symposium on Pathophysiology of Ageing and Age-Related diseases was held in Palermo, Italy. Here, the lectures of M. Racchi on History and future perspectives of Alzheimer Biomarkers and of G. Scapagnini on Cellular Stress Response and Brain Ageing are summarized. Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease, which in Western society mainly accounts for clinica dementia. AD prevention is an important goal of ongoing research. Two objectives must be accomplished to make prevention feasible: i) individuals at high risk of AD need to be identified before the earliest symptoms become evident, by which time extensive neurodegeneration has already occurred and intervention to prevent the disease is likely to be less successful and ii) safe and effective interventions need to be developed that lead to a decrease in expression of this pathology. On the whole, data here reviewed strongly suggest that the measurement of conformationally altered p53 in blood cells has a high ability to discriminate AD cases from normal ageing, Parkinson's disease and other dementias. On the other hand, available data on the involvement of curcumin in restoring cellular homeostasis and rebalancing redox equilibrium, suggest that curcumin might be a useful adjunct in the treatment of neurodegenerative illnesses characterized by inflammation, such as AD.

  19. Intranasal delivery of bone marrow-derived mesenchymal stem cells, macrophages, and microglia to the brain in mouse models of Alzheimer's and Parkinson's disease.