Treat Alzheimer Disease Before It Is Symptomatic

University of Texas Southwestern Medical Center, Dallas.
Archives of neurology (Impact Factor: 7.01). 06/2011; 68(10):1237-8. DOI: 10.1001/archneurol.2011.135
Source: PubMed
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    ABSTRACT: Immunotherapy might provide an effective treatment for Alzheimer disease (AD). A unique feature of AD immunotherapies is that an immune response against a self antigen needs to be elicited without causing adverse autoimmune reactions. Current research is focussed on two possible targets in this regard: One is the inhibition of accumulation and deposition of Amyloid beta 1-42 (Aβ42), which is one of the major peptides found in senile plaques and the second target is hyperphosphorylated tau, which forms neurofibrillary tangles inside the nerve cell and shows association with the progression of dementia. Mouse models have shown that immunotherapy targeting Aβ42 as well as tau with the respective anti-Aβ or anti-tau antibodies can provide significant improvements in these mice. While anti-Aβ immunotherapy (active and passive immunizations) is already in several stages of clinical trials, tau based immunizations have been analyzed only in mouse models. Recently, as a significant correlation of progression of dementia and levels of phoshorylated tau was found, high interest has again focussed on further development of tau based therapies. While Aβ immunotherapy might delay the onset of AD, immunotherapy targeting tau might provide benefits in later stages of this disease. And last but not least, targeting Aβ and tau simultaneously with immunotherapy might provide additional therapeutic effects as these two pathologies are likely synergistic; an approach which has not been tested yet. In this review, we will summarize animal models used to test possible therapies for AD, some of the facts about Aβ42 and tau biology, present on overview on halted, ongoing and upcoming clinical trials together with ongoing preclinical studies targeting tau or Aβ42.
    08/2013; 2013(2):105-114. DOI:10.2147/ITT.S31428
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    ABSTRACT: Dementias are the most common neurodegenerative diseases and they are increasingly becoming a major public health problem. The most common form of dementia, affecting over 20 million people worldwide, is Alzheimer’s disease (AD). AD is a neurodegenerative disease of the central nervous system mainly found in older adults, with an incidence that increases with age. With the development of newer technologies, including genetic screening technologies and PET/MRI scanning, the role of genetic studies and neuroimaging is being redefined; indeed, these approaches are able to provide support not only in the clinical diagnosis of dementia, but also in its presymptomatic evaluation. Many researchers agree that early identification of AD, before abnormal accumulation of amyloid and tau proteins, could provide an opportunity to hinder the progression of the disease. [18F]2-fluoro-2-deoxy-d-glucose (FDG) PET studies have shown that decreased glucose metabolism in AD precedes clinical diagnosis and that the degree of clinical disability in AD correlates closely with the magnitude of the reduction in brain glucose metabolism. Data on presymptomatic mutation carriers from families with known early-onset autosomal dominant AD (familial AD) show reductions in the cerebral metabolic rate of glucose (CMRglc), consistent with the expected AD PET pattern, in the absence of severe atrophy on MRI. These results suggest that PET CMRglc measures have the potential to serve as preclinical biomarkers of dementia, useful also for tracking disease progression. This review highlights the role of genetics and FDG PET in understanding the pathogenesis of dementia.
    08/2013; 1(4). DOI:10.1007/s40336-013-0028-9
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    ABSTRACT: One of the challenges of our society is to find a treatment or cure for Alzheimer's disease (AD). AD is the leading form of age-related dementia and with the increase of life expectancy worldwide, the social and economic burden from this disease will increase dramatically. It is a progressive and, in regard to clinical scores, a highly variable disease. AD pathogenesis has been associated with the accumulation, aggregation, and deposition of amyloid beta (Abeta) peptides in the brain. Hallmarks of AD are the amyloid plaques consisting of fibrillar Abeta and neurofibrillary tangles which are intracellular fibrils of hyperphosphorylated tau protein that develop later in this disease. The amyloid cascade hypothesis postulates that Abeta deposition is an initial event in the multifactorial pathogenesis and Abeta deposition may precede AD symptoms in some patients by at least 20 years. Amyloid beta therapy with active and passive immunizations against Abeta has a high possibility to be effective in removing Abeta from brain and might thus prevent the downstream pathology. Since 2000 a number of clinical trials for AD immunotherapy have started, have failed, and are continuing to be pursued. This article will review these clinical trials and ongoing research in this regard.
    Discovery medicine 05/2013; 15(84):319-326.