Similarly, Bieloschsky silver impregnation revealed no clear pathology in the blank and saline groups, but neurofibrillary tangles
in the treatment group (Fig.
are twisted fibers of abnormal tau protein that accumulate inside neurons.
While the mouse models of Alzheimer's disease that express the gene variants causing the inherited early-onset form of the disease do develop amyloid plaques in their brains and memory deficits, the neurofibrillary tangles
that cause most of the damage do not appear.
This new ability to see tau neurofibrillary tangles
in vivo "should eventually enable us to more efficiently develop preventive therapies and even treatments for the actual symptoms," he said.
(NFTs) in AD brain are consist of paired helical filaments (PHFs), which are mainly composed of hyperphosphorylated tau protein (Maccioni et al.
Until recently, the hallmark changes in the brain leading to a diagnosis of Alzheimer's disease could be seen only after death, in brain sections treated to reveal plaques containing beta-amyloid protein and neurofibrillary tangles
containing abnormal tau protein.
Only characteristic feature was neurofibrillary tangles
with a few small round cells.
AD is a neurodegenerative process in which amyloid protein forms plaques and misprocessed tau protein forms neurofibrillary tangles
in the brain, disrupting neural function.
The presence of excess amount of A[sz] deposits and neurofibrillary tangles
, NFTs, 5-6 comprising of hyperphosphorylated Tau proteins are the hallmarks of an AD brain.
These changes include increased levels of amy-loid-beta42 in the blood and decreased levels in the cerebrospinal fluid, compared with noncarriers (reflecting the presence of amyloid plaques in the brain) and elevated levels of tau and phosphorylated tau in the cerebrospinal fluid, compared with noncarriers (reflecting the presence of neurofibrillary tangles
and/or brain cell death).
The major pathologic findings in the AD brain at autopsy are amyloid plaques (extracellular), neurofibrillary tangles
(intracellular), and the loss of synaptic connections.
The neuropathological diagnosis in the participants who did not meet pathological criteria for AD included dementia with Lewy bodies, hippocampal sclerosis, Parkinson's disease, subcortical microscopic infarct, mesial temporal lobe neurofibrillary tangles
, neurofibrillary tangles
with argyrophilic grains and glial tauopathy, and no neuropathology," the authors wrote.