Flashcards in Neural Regeneration Deck (40):
central axon damaged what happens? 3 things
inhibited by glial scar
how does the PNS neuron look after nerve injury?
1. peripheral nucleus
2. loss of Nissl substance
what is chromolysis/chromatolysis?
loss of Nissl substance
What is Wallerian Degeneration?
degen of axon/myelin below injury, mopped up by Macrophages
3 weeks post injury to PNS what do you get?
schwann cells proliferate, compact cord
How fast do PNS axons regrow?
how long for successful regen in PNS since initial injury?
How does the regenned PNS nerve look compared to normal?
what happens if you get unsuccessful PNS regen?
Repair in PNS is faster when?
crushed vs. cut
main therapeutic approach to PNS injury?
oligodendrocytes and CNS regen do what?
secondary damage minutes to hours in SCI include 5 things:
2. Ca2+ influx
3. lipid peroxidation/free radicals
4. glutamate excitotoxicity
5. BBB break down
Treatment for SCI degenerative insults?
Hours to days/weeks what happens in SCI? what happens? 3 things?
immune cells infiltrate
what is a syrinx?
cavity formation for meningeal fibroblasts in SCI
What in the injury environment inhibits CNS regen? 2 big things things
4 things needed to repair CNS?
2. Axononal regen/functional integration
3. modulate astrocytic gliosis
4. neural stem cells
2 approaches to neural stem cells are?
1. mobilise endogenous cells
2. transplant exogenous cells
Another reason for lack of CNS regen besides injury environment?
lack of trophic support
no growth promoting factors
what is sprouting?
an adjacent nerve grows new processes to take over injured nerve's functions
Astrocytic gliosis does what?
extracelular matrix, proteogylcans
becomes glial scar = barrier to regen
research to prevent Astrocytic gliosis?
blocking extracellular matrix
what happens if you knock out astrocytes completely in an SCI?
no regen at all
approach for Astrocytic gliosis?
block inhibitors secreted by astrocytes
What is Nogo? treatments?
What are axon guidance molecules?
promote, repel or guid regrowing axons
What does Nogo receptors activate?
Rho signalling = inhibits axon regrowth
What are Eph/Ephrins?
possible axon guidance molecules
What does Rho kinase in SCIs do?
activates astrocytes inhibiting regrowth
CNA vs. PNS degen?
CNA vs. PNS nerve structure after injury?
Schwann cells do what to injured PNS?
supports axon regrowth
What are the two main regions of neural stem cells?
1. subventricular zone (lateral ventricle)
2. subgranular zone (hippocampus)
Problems with endogenous neural stem cells in SCIs? 4:
2. migration (blocked by inflamm/gliosis
what are iPSC and ESC?
induced pluripotent stem cell
embryonic stem cell
what kind of therapy is likely for SCI Rx?
How to help with functional regen?
3 myelin proteins are? what do they do?
MAG: myelin-associated glycoprotein
OMcp: oligodendrocyte myelin glycoprotein
bind to NogoR = inhibit regen