Tripartite Synapse

Oct 25, 2019

Neurons tend to be the stars of the show in neuroscience but astrocytes are another type of cell that may play a central role in regulating signaling in the brain. In this project, I focused my study on the role that astrocytes play in modulating synaptic signaling mediated by glutamate. The majority of this work was done during my Master’s in Bioengineering at UPenn.

Astrocytes are a fascinating species in the brain. A relatively underdog, people don’t see astrocytes as active participants in core brain functions.

Tripartite Synapse

Neurotransmitters are molecules that travel from the pre-synaptic neuron axon to the post-synaptic neuron dendritic spine. Astrocytes have been shown to have their own supply of neurotransmitters and in vitro evidence has suggested that astrocytes can release glutamate themselves based on their own separate signaling pathways. The reach of this astrocytic glutamate is unclear; do they reach the synapse in the same concentration that pre-synaptic glutamate does? Do they induce significant activation of extrasynaptic glutamate receptors, receptors that typically are not activated by presynaptic glutamate release?

  • Smoldyn Simulation - code used to run Smoldyn simulation; requires Smoldyn V3 @Github
  • Check out my (attempt) at a CUDA-enabled stochastic simulator here
  • Geometric Model - Blender model of a dendritic spine + synapse @Github

Multiplex Networks

Networks of neurons are thought to be the vehicle of higher-order brain functions. Interactions between two networks with drastically different properties give rise to fascinating dynamics in both. How does the network of astrocytes, with its slower signaling, affect the network of neurons?

  • Simplified dendrite model to characterize effect of astrocytic glutamate here
  • Simplified multiplex network model here with associated BMES poster

Astrocyte-mediated DBS effects

DBS is thought to modulate cells of the neural immune system. Astrocytes could be one potential target. In this project,

ms published
Head of Applied Science, Senior Product Manager

Neuroengineer, Control Theorist.

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