Cortical Layer 5 Pyramidal Neuron GluN2B-Mediated Hyperactivity Drives Tau Secretion Into Glymphatic Flow

GRIN2B (L5 pyramidal neurons); downstream: ADAM10/ADAM17 neuroscience market 68% proposed
Composite
68%
Novelty
68%
Feasibility
68%
Impact
72%
Mechanistic
68%
Druggability
65%
Safety
70%
Confidence
70%

Mechanistic description

Hyperactive GluN2B in L5 corticothalamic neurons increases extracellular glutamate, activating astrocytes and oligodendrocytes to release tau via exosome pathways. Enhanced neuronal activity simultaneously increases interstitial flow, redirecting tau-seed-bearing exosomes into perivascular channels for clearance—or facilitating prion-like spreading. Links activity-dependent tau release to glymphatic routing.

Evidence for (3)

  • Activity-dependent tau release is NMDAR-dependent

    PMID:28609677

  • Glymphatic clearance inversely correlates with wakefulness

    PMID:22641029

  • L5 neurons project to both thalamus and pia, positioning as integration points

    PMID:N/A

Evidence against (2)

  • Activity-dependent tau release studies mostly in vitro; trans-synaptic spreading uses different mechanisms

    PMID:N/A

  • Glymphatic routing of exosomes not directly demonstrated

    PMID:N/A