L14 Alzheimer's Disease

Question 1

What is Alzheimers Disease

Answer 1

• Most common neurodegenerative disease
• Progressive neurological disease which causes dementia
• Prevalence increases with age
• Average survival from diagnosis: 8-10 years
• No cure

Question 2

Stage 1 of Symptoms

Answer 2

Increased forgetfulness

Question 3

Stage 2 of symptoms

Answer 3

severe memory loss
storage of new memories impaired
errors in judgement
dysphasia
restlessness
mood changes
disorientation
psychosis
agression

Question 4

Stage 3 of symptoms

Answer 4

Presymptomatic personality lost
Mental emptiness
Deillitation/be/wheelchair

Question 5

Cognitive Symptoms

Answer 5

-amnesia
-aphasia - difficulty with language
-agnosia- difficulty identifying objects
-apraxia-problems with complex movements
-impaired executive function, reasoning

Question 6

Behavioral

Answer 6

Depression
Aggression
Apathy
Psychosis
Psychomotor agitation

Question 7

Functional

Answer 7

ADLS
IADLS

Question 8

Types of Alzheimer’s

Answer 8

Early onset 5% - inherited
Late onset 95%- sporadic

Question 9

What happens in a brain with alzheimers

Answer 9

Cerebral cortex degenerates damaging areas involved in thinking, planning and remembering

Hippocampus affected (new memories)

Ventricles grow larger (fluid filled spaces)

Question 10

Pathology of Alzheimers

Answer 10

1) Deposition of B-amyloid protein around neurons (Plaques)

2) Presence of Intracellular accumulation of tau proteins inside neurons (Tangles)

Question 11

Investigating Plaques

Answer 11

Plaques form when small protein pieces called B amyloid clump together

B amyloid is part of a larger protein APP

B amyloid is seperated from APP by two enzymes = y and b secretase

B amyloid is chemically sticky and clumps to form plaques on synapses and around neurons

Question 12

Investigate Tangles

Answer 12

Tangles are clumps of tau proteins inside neurons

In a healthy neuron tau binds to microtubules in axons , vital for structure and function

In Alzheimer’s, tau comes off microtubules moves into soma and dendrites - gains aberrant functions and sticks to itself forming paired filaments and insoluble clumps

Neurons with tangles eventually die

Question 13

How are Plaques and tangles linked to disease symptoms

Answer 13

Stage 1- they appear in areas -learning, memory and thinking

Changes may begin 10 years or more before diagnosis

Stage 2 - appear in areas associated with speech understanding and orientation

Lasts 2-10 years

Stage 3- widespread in cortex
severe neuron loss
may last 1-5 years

Question 14

What is the neurochemical process in the brain

Answer 14

Neurons in the hippocampus and cerebral cortex that produce acetylcholine degenerate

Loss in Cholinergic function correlates with cognitive and memory deficits

Question 15

Molecular genetic

Answer 15

APP gene
Presenilin 1
Tau
Apoliopoprotein

Question 16

Diagnosis

Answer 16

Medical History
Interviews with family members
Memory Tests:
- MMSE
-MoCA

Absence of other neurological symptoms
Brain Imaging:
- MRI
-CT

Question 17

Treatment

Answer 17

Acetylcholinesterase inhibitors– increases the synthesis of acetylcholine
Acetylcholine → → Choline + acetic acid
↑
Acetylcholinesterase

• Memantine– blocks the effect of high levels of glutamate
• Drugs for psychiatric and behavioural symptoms– Neuroleptics– Antidepressants
• (Other)– (Antioxidants e.g.. vitamin E)