Heat Shock Proteins Function as Signaling Molecules to Mediate Neuron-Glia Communication During Aging

Area of Science:

• Neuroscience
• Cell Biology
• Aging Research

Background:

• Neuron-glia communication is vital for brain development and function.
• Traditional signaling involves secreted or juxtacrine signals via ligand-receptor interactions.
• Understanding novel communication pathways is crucial for brain aging research.

Purpose of the Study:

• To identify a novel mechanism of neuron-glia signal transduction.
• To investigate the role of extracellular vesicles in transmitting signals between neurons and glia.
• To elucidate the molecular pathways involved in neuron-glia crosstalk during brain aging.

Main Methods:

• Utilized *Caenorhabditis elegans* amphid sensory organ model.
• Investigated extracellular vesicle-mediated protein transfer from neurons to glia.
• Analyzed the activation of the IRE1-XBP1 pathway in glia.
• Examined transcriptional regulation of chondroitin synthases.

Main Results:

• Neurons transmit heat shock proteins (HSP) to glia via extracellular vesicles.
• Neuronal HSPs activate the IRE1-XBP1 pathway in glia, creating a positive feedback loop.
• Activation of IRE1-XBP1 leads to chondroitin synthase upregulation.
• This process protects glia-embedded neurons from age-related functional decline.

Conclusions:

• Discovered a novel mechanism of neuron-glia communication through extracellular vesicle protein transfer.
• Demonstrated the role of neuronal HSPs and the IRE1-XBP1 pathway in glia-mediated neuroprotection.
• Provided new insights into the molecular basis of brain aging and neuron-glia interactions.