Regeneration Flashcards
What is Wallerian Degeneration?
PNS
Following injury, Schwann cells detach from axons and start proliferating and help recruit macrophages to clear debris.
At the same time, expression of stimulating factors by SCs create a favorable environment for nerve re growth toward target organ
What are the differences and similarities of regeneration in the CNS and PNS?
CNS:
PNS:
What is Chromatolysis?
Cytoplasmic pallor and eccentricity of the nucleus (pushed to the side) signs of Chromatolysis
Happens upon exposure to neuro toxic chemical
What are anticipated advantages of using stem cells/pluripotent cells for therapeutic intervention in the nervous system?
- May form multiple types of cells needed for repair
- May be engineered to secrete factors needed for the regeneration process
- May be monitored for the progression of repair
What happens when there is no axonal regeneration?
Inhibitory molecules: Nogo, MAG, Omgp
Astrocytes –> gliosis –> glial scar forms
What are Nogo, MAG, and Omgp?
Nogo - no go (TM protein)
MAG - myelin associated glycoprotein
Omgp - Oligodendrocyte-myelin glycoprotein
What is the function of Nogo, MAG, and Omgp?
Inhibit axon formation
All three bind Nogo receptor 66
Nogo’s amino binds integrin blocking adhesion
What is distal axonopathy?
Degeneration of axon and myelin develops first in the most distal parts of the axon
What animal regenerates axonal tracts, cells, and tissue in the CNS?
Zebra fish
What animal model regrows CNS tissue without the formation of glial scars?
Salamander
What is IPS?
Induced pluripotent cells
- differentiate into an somatic cell
- overcomes ethical problems
What is a current challenge to stem cell use?
- toxicity
- tumor formation
- cost
- immunogenicity consequences
