Lecture 4 study questions for midterm 2 Flashcards
What evidence is there for neurogenesis in other brain regions?
Subventricular zone in the lateral ventricles and the subgranular zone of the dentate gyrus of hippocampus. New neurons are born here.
To what extent has Stem Cell Treatment been proven successful for Spinal Cord Injury?
Some researchers have shown that stem cell therapy can enhance remyelination of the spinal cord and promote the improvement of motor function
Many stem cell researchers still admit that a combinatorial approach is still necessary to treat SCI which would include rehabilitation, drugs
Single cell therapies have modest benefits
Stem cells improved ASIA impairment scale score by at least one grade in half of the patients with SCI; 42% had improvement in the urinary and gastrointestinal system
Cost effectiveness, regulatory guidelines
Many adverse effects were observed: neuropathic pain, abnormal feeling, muscle spasms, vomiting, UTI
List and briefly describe five primary and secondary injury mechanisms associated with a SCI.
Edema
Hemorrhage
Apoptosis
Necrosis: the death of oligodendrocytes and neurons results in axonal demyelination and disruption of synaptic transmission
Excitoxicity: excessive exposure to neurotransmitters and overstimulation of membrane receptors
Blood vessel occlusion
List and briefly describe sources of stem cells tested for transplantation into the injured spinal cord.
OPC: oligodendrocyte progenitor cells
NSPC: neural stem/progenitor cells
iPSCs: induced pluripotent stem cells
MSCs: mesenchymal stem cells
BMSCs: bone marrow derived stromal cells
List 5 or more potential mechanisms of spinal cord repair following stem cell transplantation.
Replacement of oligodendrocytes or neurons by transplanted cells
Remyelination of spared axons
Promotion of angiogenesis
Reduction of inflammation
Bridging of the cyst/cavity by transplanted cells
Enhanced preservation of host neuronal and glial cells, for example, by secreted neurotrophins from transplanted cells,
In practical terms, what are some of the biggest hurdles in designing and carrying out clinical translation of stem cell therapy for SCI?
Trials are conducted with small number of patients and without controls which make the assessment of efficacy not possible. Must caution against over reliance of results.
Stem cell treatment is expensive.
Every SCI patient is unique and what worked in one trial may not be applicable to the given patient
Briefly describe experimental strategies to stop injury progression and offer neuroprotection after a SCI.
Surgical decompression to mitigate secondary damage caused by edema. Involves opening the vertebral canal to create more space for the spinal cord and nerves
Neuroprotective strategies: drugs, hypothermia, dietary modificiation
Activity dependent activation of spared circuits
Stem cell therapy: the implantation of human embryonic stem cell derived oligodendrocyte progenitor cells
