Composite
Novelty
Feasibility
Impact
Mechanistic
75%
Druggability
50%
Safety
45%
Confidence

Mechanistic description

This hypothesis proposes that precise, neuron-specific TFEB modulation at optimal levels, combined with trehalose co-treatment, can restore lysosomal function in Alzheimer’s disease while avoiding the detrimental effects of global TFEB activation. Building on the ‘Goldilocks principle’ that TFEB requires precise dosing to avoid toxicity, we will use neuron-specific promoters (such as CaMKII or synapsin) to drive moderate TFEB overexpression exclusively in excitatory neurons of AD-affected brain regions. This targeted approach circumvents the neuroinflammatory and microglial activation issues associated with global TFEB upregulation, while avoiding the α-synuclein-related APP processing defects seen with non-specific overexpression. Trehalose will be administered as a complementary TFEB-independent lysosomal enhancer, providing additive benefits through its chemical chaperone properties and alternative autophagy stimulation pathways. This dual intervention targets the fundamental cellular waste management deficits underlying amyloid-beta and tau accumulation at synapses, where lysosomal dysfunction is most critical for cognitive decline. The neuron-restricted TFEB expression will restore lysosomal biogenesis specifically where pathological proteins accumulate, while trehalose provides system-wide autophagy support without pleiotropic transcriptional effects. Evidence will be gathered through longitudinal analysis of APP/PS1 and 3xTg-AD mouse models using neuron-specific TFEB vectors plus trehalose treatment, measuring synaptic protein clearance, electrophysiological function, and cognitive performance. Biomarker studies will track lysosomal enzyme activity in cerebrospinal fluid and assess changes in brain amyloid and tau burden using PET imaging, focusing on early-stage intervention before extensive neuronal loss occurs.

Evidence for (6)

  • TFEB overexpression reduces tau aggregation and Aβ toxicity in cellular models

  • Impaired TFEB nuclear localization observed in AD brain tissue with mTOR hyperactivation

  • Trehalose enhances lysosomal biogenesis and reduces protein aggregates in neurodegeneration models

  • Autophagosome accumulation in AD synapses indicates upstream autophagy initiation is intact but downstream lysosomal degradation is blocked

  • mTOR inhibitors (rapamycin analogs) enable TFEB nuclear translocation

  • TFEB activation bypasses upstream mTOR dysregulation and directly enhances lysosomal gene expression

Evidence against (6)

  • TFEB regulates hundreds of genes beyond lysosomal biogenesis including lipid metabolism and inflammatory pathways

  • TFEB overexpression paradoxically increases neurodegeneration in α-synuclein models via APP-like substrate processing

  • Global TFEB activation in microglia exacerbates neuroinflammation through enhanced lysosomal antigen presentation

  • TFEB haploinsufficiency is protective in certain aging paradigms, suggesting a 'Goldilocks' principle

  • Trehalose acts as chemical chaperone independently of TFEB

  • Genistein is a broad kinase inhibitor with estrogenic activity