How Our Brain Drains Its Waste Products

How Our Brain Drains Its Waste Products

From Ground Truths by Eric Topol

December 21, 2025 · 56 min

About this episode

The episode discusses brain drainage and immune system surveillance with neuroscientist Jonathan Kipnis.

Jonathan Kipnis is a neuroscientist, the Alan A. and Edith L. Wolff Distinguished Professor of Pathology and Immunology at Washington University, St. Louis, who discovered meningeal lymphatics and has been a prolific researcher in brain drainage and the continuous immune system surveillance of the brain. I made this infographic with the help of Notebook LM to summarize many of the concepts we discussed. (Notebook LM is free and worth trying) We went over his new review with 24 co-author leading experts in the recent issue of Neuron A Clever Cover The drainage system anatomy on influx and efflux (blue arrows) The 3 ways the flow of glymphatics are modulated. I mentioned the recent studies that show atrial fibrillation, via reduced cardiac pulsation, has an effect on reducing glymphatic flow. We also discussed his recent review on the immune surveillance system in Cell: A schematic of key channels for the “faucet” and “drain” and how the system changes from healthy to central nervous system autoimmune diseases (such as multiple sclerosis) and aging with different immune bar codes. The outsized role of astrocytes in the brain, a subject of recent Nature feature, was also mentioned…

People in this episode

Host: Eric Topol

Guest: Jonathan Kipnis

Topics covered

  • brain drainage
  • immune system
  • glymphatic flow
  • neuroscience
  • autoimmune diseases
  • astrocytes

Keywords

  • glymphatics
  • atrial fibrillation
  • immune surveillance
  • multiple sclerosis
  • astrocytes
  • brain anatomy

Mentioned in this episode

Organizations: Washington University, Neuron, Cell, Nature, Nature Immunology

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