9 neuropathology lecture 3: neurodegenerative diseases Flashcards
T/F- those diseases that affect primarily neurons of the cerebral cortex result in dementia with very little movement disorder, while those affecting primarily neurons of the cerebellum, brainstem, or spinal cord result in movement and/or autonomic disorders with very little dementia.
true
Name 3 degenerative diseases affecting the cerebral cortex
Alzheimers
Pick’s disease
Dementia with Lewy Bodies
Name 4 degenerative diseases affecting the basal ganglia and brainstem
- Parkinsons disesease
- Multiple system atrophy
- Progressive supranuclear palsy
- Huntington’s disease
Name 1 category of degenerative disease affecting the spinocerebellar tracts
spinocerebellar ataxias
Name one degenerative disease affecting motor neurons
amyotrophic lateral sclerosis
Define dementia
acquired, cognitive impairments in an alert individual that are sufficiently severe to affect occupational and/or social functioning
Pure alzheimer’s accounts for ___% of all dementias
40
Alzheimer’s affects ___% of individuals over 65 and ___% of individuals over 85
5%
50%
T/F- the majority of cases of alzheimer’s disease are familial
False, only 5-10% are familial
How is alzheimer’s diagnosed?
- Clinical dementia with relatively specific, testable cognitive abnormalities
- Absence of other forms of organic dementia (tumors, infarcts, etc.)
- Imaging studies to show cortical atrophy
- Autopsy confirmation of appropriate histopathology
Grossly, in alzheimers what will you see?
cortical atrophy
What will histopathology show for alzheimers?
− Neuritic plaques
− Neurofibrillary tangles −Amyloid angiopathy
Neuritic plaques (senile plaques) are a deposition of amyloid (product of amyloid precursor protein) which result in local injury to neuronal processes. What are attempts at repair called?
“sprouting”
T/F- neuritic plaques have a close association with cerebral capillaries
true
T/F- amyloid precursor protein is a selectively expressed transmembrane protein
False it is ubiquitously expressed transmembrane proteins:
neurofibrilary tangles are ____philic
argyrophilic (silver stain)
What gene encodes tau?
17q21 (6 isoforms in the CNS)
Where in a neuron is tau located?
predominantly in axons
What does tau do?
promotes microtubule polymerization and stabilization
T/F- the tau in neurofibrillary tangles is abnormally phosphorylated
true
What will gross image of pick’s disease brain show?
cortical atrophy
What will histopathology of Pick’s disease show?
• Pick bodies – tau containing intraneuronal inclusion bodies
• Neurofibrillary tangles - also contain tau, but filaments are not
paired helical filaments
• No neuritic plaques or amyloid angiopathy
Pick’s disease affects the _____lobe primarily and spares the_______
frontal lobe most affected
sparing of the posterior superior tempral gyrus
What pathway is damaged in parkinsons?
Nigrostriatal dopaminergic system
Name 3 symptoms of parkinson disease
– Tremor
– Loss of spontaneous movement
– Rigidity
Parkinson disease is the most common underlying cause of parkinsonism. What are other possibilites?
– Multiple system degenerations
– Progressive supranuclear palsy
– Drugs – e.g. haloperidol, methotrexate
– Toxins – MPTP (a contaminate of meperidine, aka Demerol)
What age is the peak incidence of parkinson disease?
55-65 years
