Misfolding Of Amyloid Beta And Tau In Alzheimers And Other Neurodegenerative Diseases

Neurofibrillary tangles (NFTs) composed of intracellular aggregates of tau protein are a key neuropathological feature of Alzheimer’s Disease (AD) and other neurodegenerative diseases, collectively termed tauopathies. The abundance of NFTs has been reported to correlate positively with the severity of cognitive impairment in AD. However, accumulating evidences derived from studies of experimental models have identified that NFTs themselves may not be neurotoxic. Now, many of tau researchers are seeking a “toxic” form of tau protein. Moreover, it was suggested that a “toxic” tau was capable to seed aggregation of native tau protein and to propagate in a prion-like manner. However, the exact neurotoxic tau species remain unclear. Because mature tangles seem to be non-toxic component, “tau oligomers” as the candidate of “toxic” tau have been investigated for more than one decade. In this topic, we will discuss our consensus of “tau oligomers” because the term of “tau oligomers” [e.g. dimer (disulfide bond-dependent or independent), multimer (more than dimer), granular (definition by EM or AFM) and maybe small filamentous aggregates] has been used by each researchers definition. From a biochemical point of view, tau protein has several unique characteristics such as natively unfolded conformation, thermo-stability, acid-stability, and capability of post-translational modifications. Although tau protein research has been continued for a long time, we are still missing the mechanisms of NFT formation. It is unclear how the conversion is occurred from natively unfolded protein to abnormally mis-folded protein. It remains unknown how tau protein can be formed filaments [e.g. paired helical filament (PHF), straight filament and twisted filament] in cells albeit in vitro studies confirmed tau self-assembly by several inducing factors. Researchers are still debating whether tau oligomerization is primary event rather than tau phosphorylation in the tau pathogenesis. Inhibition of either tau phosphorylation or aggregation has been investigated for the prevention of tauopathies, however, it will make an irrelevant result if we don’t know an exact target of neurotoxicity. It is a time to have a consensus of definition, terminology and methodology for the identification of “tau oligomers”.

Amyloid-beta and Tau are both proteins well known for their involvement in Alzheimer's disease. Both proteins misfolding and aggregate are deposited as cross-beta amyloid fibrils in the tissues. Although Alzheimer's disease was discovered over 100 years ago, the role of protein misfolding in the pathology and cause of Alzheimer's disease remains unclear. Misfolding of Amyloid-beta and tau in Alzheimer's and Other Neurodegenerative Diseases describes historical discoveries of these two major proteins in Alzheimer's disease and other neurodegenerative conditions. The book navigates through the importance of protein self-assembly, protein conformational change and structural studies in understanding the positioning in the disease pathway. How these proteins are involved in the pathway to neuronal dysfunction and, the importance of understanding protein conformation and deposition for diagnosis are also highlighted.

Research focused on protein folding, misfolding, and aggregation is leading to major advances across biochemistry and medicine. The elucidation of a folding code is proving to be of extreme importance in the postgenomic era, where a number of orphan genes have been identified for which no clear function has yet been established. This research is starting to shed light on the molecular and biochemical basis of a number of neurodegenerative diseases of dramatic impact. Protein Misfolding in Neurodegenerative Diseases: Mechanisms and Therapeutic Strategies addresses key issues concerning protein misfolding and aggregation in neurodegenerative diseases. Building on recent developments, including the recognition of protein misfolding as both a marker and a causal agent, the text presents the work of those who are actively pursuing more effective treatments, as well as preventative measures, and a possible cure. These include the use of molecular chaperones to control misfolding and novel pharmaceuticals, as well as the potential role of various inhibitors and NSAIDS. A Comprehensive Multifaceted Examination of the Complex Causal Agents Implicated in Protein Misfolding Divided into five sections, this groundbreaking text provides up-to-date accounts for Alzheimer’s, Parkinson’s, Huntington’s, Amyotrophic Lateral Sclerosis and Transmissible Spongiform Encephalitis. It also explores the highly likelihood that multiple factors, including oxidative stress, play a role in these complex diseases.

The Molecular and Cellular Basis of Neurodegenerative Diseases: Underlying Mechanisms presents the pathology, genetics, biochemistry and cell biology of the major human neurodegenerative diseases, including Alzheimer’s, Parkinson’s, frontotemporal dementia, ALS, Huntington’s, and prion diseases. Edited and authored by internationally recognized leaders in the field, the book's chapters explore their pathogenic commonalities and differences, also including discussions of animal models and prospects for therapeutics. Diseases are presented first, with common mechanisms later. Individual chapters discuss each major neurodegenerative disease, integrating this information to offer multiple molecular and cellular mechanisms that diseases may have in common. This book provides readers with a timely update on this rapidly advancing area of investigation, presenting an invaluable resource for researchers in the field. Covers the spectrum of neurodegenerative diseases and their complex genetic, pathological, biochemical and cellular features Focuses on leading hypotheses regarding the biochemical and cellular dysfunctions that cause neurodegeneration Details features, advantages and limitations of animal models, as well as prospects for therapeutic development Authored by internationally recognized leaders in the field Includes illustrations that help clarify and consolidate complex concepts

This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.

This book highlights the pathophysiological complexities of the mechanisms and factors that are likely to be involved in a range of neuroinflammatory and neurodegenerative diseases including Alzheimer's disease, other Dementia, Parkinson Diseases and Multiple Sclerosis. The spectrum of diverse factors involved in neurodegeneration, such as protein aggregation, oxidative stress, caspases and secretase, regulators, cholesterol, zinc, microglia, astrocytes, oligodendrocytes, etc, have been discussed in the context of disease progression. In addition, novel approaches to therapeutic interventions have also been presented. It is hoped that students, scientists and clinicians shall find this very informative book immensely useful and thought-provoking.

Neurodegenerative Disorders as Proteinopathies: Phenotypic Relationships.- Towards a Molecular Classification of Neurodegenerative Disease.- Racial and Ethnic Influences on the Expression of the Genotype in Neurodegenerative Diseases.- Causes and Consequences of Oxidative Stress in Neurodegenerative Diseases.- Early Onset Familial Alzheimer's Disease: Is a Mutation Predictive of Pathology?.- Identification of Genes that Modify the Age of Onset in a Large Familial Alzheimer's Disease Kindred.- Variable Phenotype of Alzheimer's Disease with Spastic Paraparesis.- Presenilin Mutations: Variations in the Behavioral Phenotype with an Emphasis on the Frontotemporal Dementia Phenoytpe.- Frontotemporal Dementias: Genotypes and Phenotypes.- Chromosome 17-Linked Frontotemporal Dementia with Ubiquitin-Positive, tau-Negative Inclusions.- Variations of the Phenotype in Frontotemporal Dementias.- Phenotype/Genotype Correlations in Parkinson's Disease.- Subject Index

Filling a noticeable gap in the market for a new text solely focused on Dementia with Lewy Bodies, this book discusses cutting-edge topics covering the condition from diagnosis to management, as well as what is known about the neurobiological changes involved. With huge progress having been made over the last decade in terms of the disorder