Proteinopathies
Proteinopathies (proteopathies) are diseases where proteins are abnormally self-associating and aggregating, due to conformational changes. Protein aggregates can be intracellular, extracellular, or both. Proteinopathies can affect any organs, including amyloidosis of the heart, liver, kidneys, and lungs. The most studied proteinopathies are those of the central nervous system (CNS), including Alzheimer's disease (AD), Parkinson's disease (PD), and dementia with Lewy bodies (DLB). Proteinopathies of the nervous system affect often both central and peripheral nervous system. Prion diseases, such as Creutzfeldt-Jakob disease (CJD), are infectious proteinopathies.
PET tracers have been developed for studying the three main types of aggregated amyloid proteins: β-amyloid, tau proteins, and α-synuclein.
Most tracers are derivatives of dyes that have been used to stain tissue samples under light microscopy. Congo red and Chrysamine G derivatives bind to fibrillar β-amyloid and tau proteins, both containing stacked β-sheets. Thioflavin T derivatives bind more specifically to fibrillar β-amyloid, but also to myelin.
See also:
References:
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Tags: Amyloid-beta, Alpha-synuclein, Lewy bodies, Tau protein, Amyloidosis, Alzheimer disease, Dementia
Updated at: 2018-12-25
Created at: 2017-09-19
Written by: Vesa Oikonen