Alpha-synuclein inclusions in amygdala in the brains of patients with the parkinsonism-dementia complex of Guam.
We investigated by immunohistochemistry the deposition of alpha-synuclein in the brains of deceased patients with the parkinsonism-dementia complex (PDC) of Guam. Five of 13 PDC brains showed numerous alpha-synuclein positive neuronal inclusions and abnormal neurites, chiefly in the amygdala. Similar alpha-synuclein positive lesions were observed, although to a lesser extent, in the entorhinal cortex and the dorsal vagal nucleus. No alpha-synuclein positive inclusions were observed in motor cortex or locus coeruleus, and only a small number of positive inclusions were found in the Sommer's sector, temporal cortex, or substantia nigra. Some of the alpha-synuclein positive inclusions were reminiscent of cortical Lewy bodies (LB), but many of those in the amygdala coexisted with tau-positive pretangles and/or neurofibrillary tangles (NFT) within the same neurons. In these neurons, tau-positive shells encapsulated alpha-synuclein positive central cores or irregularly shaped alpha-synuclein-positive deposition intermingled with pretangles/NFT. Thus, the present study suggests that a common mechanism may govern aggregation of alpha-synuclein and tau in the amygdala, and that aggregation of alpha-synuclein may play some role in the neurodegenerative process of a tauopathy (i.e. PDC) in which Abeta deposition is virtually absent.
Yamazaki
M
M
Department of Neuropathology, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Japan.
Arai
Y
Y
Baba
M
M
Iwatsubo
T
T
Mori
O
O
Katayama
Y
Y
Oyanagi
K
K
D000328:Adult; D000368:Aged; D000679:Amygdala / Q000737:chemistry / Q000473:pathology*; D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology*; D003704:Dementia / Q000473:pathology*; D005455:Fluorescent Antibody Technique; D006141:Guam; D006801:Humans; D002479:Inclusion Bodies / Q000737:chemistry* / Q000473:pathology; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000032:analysis*; D020734:Parkinsonian Disorders / Q000473:pathology*; D058225:Plaque, Amyloid / Q000737:chemistry / Q000473:pathology; D051843:Synucleins; D051844:alpha-Synuclein; D016875:tau Proteins / Q000032:analysis
D009419:Nerve Tissue Proteins; C497604:SNCA protein, human; D051843:Synucleins; D051844:alpha-Synuclein; D016875:tau Proteins