Open AccessCerebral Amyloid β Protein Deposits and Other Alzheimer Lesions in Non‐Demented Elderly East Africans
Author(s) -
Ogeng'o J.A.,
Cohen D.L.,
Sayi J. G.,
Matuja W.B.,
Chande H. M.,
Kitinya J. N.,
Kimani U.K.,
Friedland R. P.,
Moris H.,
Kalaria R.N.
Publication year - 1996
Publication title -
brain pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.986
H-Index - 132
eISSN - 1750-3639
pISSN - 1015-6305
DOI - 10.1111/j.1750-3639.1996.tb00790.x
Subject(s) - pathology , senile plaques , cerebral amyloid angiopathy , autopsy , alzheimer's disease , dementia , amyloid (mycology) , medicine , disease
There is little knowledge of the existence of Alzheimer disease (AD) or Alzheimer type of dementia in indigenous populations of developing countries. In an effort to evaluate this, we assessed the deposition of amyloid β (Aβ) protein and other lesions associated with AD in brains of elderly East Africans. Brain tissues were examined from 32 subjects, aged 45 to 83 years with no apparent neurological disease, who came to autopsy at two medical Institutions in Nairobi and Dar es Salaam. An age‐matched sample from subjects who had died from similar causes in Cleveland was assessed in parallel. Of the 20 samples from Nairobi, 3 (15%) brains exhibited neocortical Aβ deposits that varied from numerous diffuse to highly localized compact or neuritic plaques, many of which were also thioflavin S positive. Two of the cases had profound AS deposition in the prefrontal and temporal cortices and one of these also exhibited moderate to severe cerebral amyloid angiopathy. Similarly, 2 of the 12 samples from Dar es Salaam exhibited diffuse and compact Aβ deposits that were also predominantly reactive for the longer Aβ 42 species compared to Aβ 40 . We also noted that Aβ plaques were variably immunoreactive for amyloid associated proteins, apolipoprotein E, serum amyloid P and complement C3. Tau protein reactive neurofibrillary tangles (NFT) were also evident in the hippocampus of 4 subjects. By comparison, 4 (20%) of the 20 samples from randomly selected autopsies performed in Cleveland showed Aβ deposits within diffuse and compact parenchymal plaques and the vasculature. These observations suggest Aβ deposition and some NFT in brains of non‐demented East Africans are qualitatively and quantitatively similar to that in age‐matched elderly controls from Cleveland. While our small scale study does not document similar prevalence rates of preclinical AD, it suggests that elderly East Africans are unlikely to escape AD as it is known in developed countries.