Lecture on CNS and Health

Introduction

• Metaphor of a household when someone is sick
• Whole household's balance is disturbed
• Brain and spinal cord function similarly to a household

Central Nervous System (CNS)

• Composed of the brain and spinal cord
• Protected by the blood-brain barrier
• Blood-brain barrier is a tight junction of endothelial cells
• Regulates what enters and exits CNS

CNS Cells

• Neurons: Most important, control functioning, movement, and feelings
• Glial cells: Support neurons
  • Oligodendrocytes: Contain myelin, insulate neurons for signal transmission
  • Astrocytes: Dense network, secrete factors to support neurons
  • Microglia: Immune cells of CNS, originate from the yolk sac, play critical role in development

Microglia Functions

• Recognize pathogens (viruses, bacteria) and damaged tissue
• Activate immune response, secrete cytokines, chemokines, and effector molecules
• Microglia express all innate immune receptors
• Engage in constant surveillance of CNS

Infection Response

• Microglia recognize virus, activate immune response
• Secrete antimicrobial cytokines, activate surrounding cells
• Chemokines recruit other immune cells
• If necessary, open blood-brain barrier to allow peripheral immune cells in
• Response called neuroinflammation

Neuroinflammation

• Vital for clearing infections and repairing injuries
• Can cause problems if prolonged or excessive
• Linked to diseases like Multiple Sclerosis, chronic pain, dementia

Multiple Sclerosis

• Prolonged neuroinflammation damages oligodendrocytes, leads to demyelination
• Neurons lose insulation, causing signal transmission issues
• Severe damage leads to neuron loss and paralysis

Chronic Pain

• Persistent pain signals create feedback loop between neurons and microglia
• Triggered by injury or disease (e.g., TMD - temporomandibular joint disease)
• Initial injury may subside, but feedback loop sustains pain

Research Focus

• Control inflammatory response by microglia in neurological diseases
• Developing compounds to reduce microglial inflammation
• Using microRNAs and naturally produced proteins to turn off inflammation

Goals in Treating CNS Diseases

• Multiple Sclerosis: Turn down inflammatory response, promote anti-inflammatory repair
• Chronic Pain: Interrupt neuron-microglia feedback loop, reduce pain without side effects

Conclusion

• Neuroinflammation is beneficial but must be regulated
• Aim to restore CNS to a normal, healthy state