Neurotoxins and Prions

Question 1

Toxins

Answer 1

diffusible molecs that can cause systemic havoc

Question 2

3 most common neurotoxins

Answer 2

• botulinum toxins
• tetanus toxins
• lethal toxins

Question 3

what does botulinum toxins target

Answer 3

target motor neuron, inhibit exocytosis of synaptic vesicles

Question 4

what does tetanus toxins target

Answer 4

targets interneurons; inhibits exocytosis of synaptic vesicles

Question 5

what does lethal toxin target

Answer 5

potentially targets all neurons; affects cytoskeleton

Question 6

what produces neurotoxins

Answer 6

clostridia bacteria

Question 7

what is the most poisionous toxin

Answer 7

botulinum toxins

Question 8

botulism acquired from

Answer 8

eating spoiled food

Question 9

what is prion disease

Answer 9

• neurological disorders caused by pathogenic proteins
• thought to be slow viruses but resistant to inactivation methods
• lack any genetic material, single misfolded p
• prion diseases is a special case of encephalitis (no inflammation, neuronal death, astrocytic gliosis)

Question 10

Commonalities of prion diseases

Answer 10

• thought to be a slow, unconventional virus
• no direct person to person transmission
• unknown reasons (sporadic)
• more than 20 mutations known to cause sporadic prion disease
• rapid progression after onset
• no cure/treatment
• definitive diagnosis only during autopsy
• lack of awareness difficult treatment

Question 11

what are the 3 types of prion disease

Answer 11

1. sporadic
2. inherited
3. acquired

Question 12

properties of prions (6)

Answer 12

• can go through filters that block bacteria/fungi/parasites
• resistant to heat or uv light
• no antibodies generated
• no adaptive immune response is induced
• can coerce normal molecs to change into their abnormal shape
  (especially alpha helical to beta sheets)
• possibly acting as chaperone

Question 13

how are prion diseases similar to neuropathologies

Answer 13

• A prion-like spreading of amyloid-β and α-synuclein have been hypothesized to cause Alzheimer’s and Parkinson’s, respectively
• Many non-infectious neurological diseases show protein aggregates and “plaques” as main pathological finding
• Alzheimer, Parkinson, ALS, Huntington
• Research on prion disease might impact our understanding of
  neurodegenerative disorders
• PrPSc accumulation only occurs if PrPC to PrPSc is faster than PrPSc clearance =same idea to amyloids accumulation, as we age, clearance slows down