Related Experiment Video
Updated: Aug 20, 2026

Sequential Extraction of Soluble and Insoluble Alpha-Synuclein from Parkinsonian Brains
Published on: January 5, 2016
Insoluble alpha-synuclein in Alzheimer's disease without Lewy body formation
Melissa Broe1, Claire E Shepherd, David M A Mann
1Prince of Wales Medical Research Institute, Sydney, 2031 Australia.
Abstract:
Insoluble alpha-synuclein plays a central role in Lewy body diseases, with considerable controversy as to whether it plays a similar role in Alzheimer's disease (AD). We assessed the tissue location and solubility of cortical alpha-synuclein in AD (without Lewy body formation) compared with controls, using sequential extraction procedures and Western immunoblotting to quantify different alpha-synuclein species in their different solubility states. Controls had no insoluble cortical alpha-synuclein and a ratio of soluble:lipid-associated alpha-synuclein of 1.2-/+0.1. Total alpha-synuclein protein was significantly increased in AD and concentrated within the lipid-associated fraction (soluble:lipid ratio 0.9-/+0.05, soluble:insoluble 1.5-/+0.1, lipid:insoluble 1.7-/+0.1) which proved difficult to localize in paraffin-embedded tissue. Tissues prepared without lipid extraction revealed alpha-synuclein-immunoreactivity in the amorphous components of mature cored AD plaques. This lipid-association of alpha-synuclein in mature AD plaques links this protein with other lipid changes thought to be important in disease pathogenesis.
Related Concept Videos
Alzheimer Disease ll: Pathophysiology
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Alzheimer Disease l: Introduction
Parkinson Disease ll: Pathophysiology
Alzheimer's Disease: Overview
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ and tau...

