Senile Dementia of the Neurofibrillary Tangle Type: A Comparison with Alzheimer’s Disease

Abstract

A subset of senile dementia, ‘senile dementia (SD) of the neurofibrillary tangle (NFT) type’ (SD-NFT), is characterized by numerous NFTs in the hippocampal region and absence or scarcity of senile plaques throughout the brain. To elucidate the pathogenesis of SD-NFT in comparison with Alzheimer’s disease (AD), we investigated the hippocampal lesions and analyzed the tau gene. The hippocampal regions from 5 patients with SD-NFT were neuropathologically evaluated in comparison with AD and nondemented control subjects. The tau gene was analyzed in 3 patients with SD-NFT. The densities of NFTs in the CA1/subiculum and entorhinal cortex of SD-NFT were significantly higher than those in AD. However, hippocampal atrophy, neuronal and synaptic loss, and astrocytic and microglial proliferation in SD-NFT were significantly mild compared with AD. There was no significant difference between SD-NFT and AD in the immunoreactivities of NFTs with different anti-tau antibodies. No mutation was found in the tau gene from the SD-NFT patients. Our results indicate that the neurodegenerative process with NFT formation of the hippocampal region in SD-NFT would be different from that in AD.

Aberrant accentuation of neurofibrillary degeneration in the hippocampus of Alzheimer's disease with amyloid precursor protein 717 and presenilin-1 gene mutations

“…This may result in unusual accentuation of NFT in the CA in the APP and PS-1 mutation cases. Although we could not find the pathogenesis for regional vulnerability to NFT in the CA, extraentorhinal NFT accentuation has been reported in the CA1-subiculum regions in senile dementia of NFT [53] and CA1 -CA2 -subiculum regions in a subset of normal elderly [54]. As in both conditions cognitive ability was not so severely disturbed and NFT density was low compared with familial AD [55], there is a possibility that severe and early intellectual decline in familial AD might be due to the profound neurodegeneration rather than affected regions.…”

The Pathology of Paraphrenia

“…The same pattern of pathology is present in centenarians without obvious dementia [53,54]. This has led some authors to conclude that NFT-SD may represent a condition of accelerated brain aging [46,[50][51][52].…”

Emerging Histomorphologic Phenotypes of Chronic Traumatic Encephalopathy in American Athletes

“…Overrepresentation of the ApoE3 allele has been reported in patients with tangle-only dementia, 21,22 whereas the ApoE4 allele has been reported to increase the risk of the development of Alzheimer disease, 7 with ApoE4/E4 homozygotes having about a 19-fold increased risk of the development of Alzheimer disease. 14 Our preliminary observation regarding…”