Role of Prions in Alzheimer's Disease: A Review

Introduction: Prions are infectious agents composed of proteins which misfold in obscure patterns and behave erroneously by transforming normal protein isoforms into the pathogenic misfolded form. We aim to review studies which suggest a connection between prions and Alzheimer's disease. Methods: Research papers are retrieved from Google Scholar using the search terms: Prions, Alzheimer's, Mechanism, Propagation, Protein, beta-amyloid, Tau Protein, Connection, Toxicity, Neurodegenerative, Cellular and Pathways. Papers are then selected on the basis of relevance, validity, and reliability. Papers which qualify are then assessed and incorporated in this review article. Results: Different models of prion-induced Alzheimer's disease have been proposed. These models suggest multiple mechanisms of cellular prion protein involvement in the pathology of Alzheimer's disease including serving as beta- amyloid oligomer receptor, direct stimulation of A beta oligomer aggregation along with Beta-secretase 1 inhibition, Tau protein inclusion, and alpha-synuclein aggregation. Evidence suggests that of Tau and A beta protein spreads in a prion-like fashion. Conclusion: The underlying mechanism of prion proteins involvement in the pathology of Alzheimer's disease remains elusive as discussed in this study. Whether or not prions have a significant role in Alzheimer's disease remains debatable. It is a very exciting avenue for research to pinpoint the prion species involved in Alzheimer's disease leading to a potential treatment.