Dual PDE4/10A inhibition restores CREB1 function and enhances neuronal resilience in models of alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) involves cognitive decline, amyloid-beta (Aβ) accumulation, tau hyperphosphorylation, and neuroinflammation. CREB1, a key transcription factor for memory, is downregulated in AD, contributing to disease progression. Phosphodiesterases 4 and 10 (PDE4 and PDE10) are key enzymes that degrade cAMP, a second messenger involved in CREB signaling, synaptic plasticity, and neuroprotection. Dysregulation of PDE activity has been implicated in AD and other neurodegenerative disorders. METHODS: We used human iPSC-derived cortical neurons and microglia, along with the APP/PS1 mouse model, to investigate the role of CREB1 and assess the therapeutic potential of dual PDE4/10A inhibition in AD. RESULTS: CREB1 deficiency in neurons increased Aβ and p-tau231 accumulation. Dual inhibition of PDE4 and PDE10A activated the cAMP-PKA-CREB pathway, restoring CREB1 activity, reducing Aβ and p-tau231, and mitigating neuroinflammation. This intervention improved synaptic plasticity and cognitive performance in vivo. CONCLUSIONS: Our findings demonstrate that dual PDE4/10A inhibition synergistically enhances the cAMP-PKA-CREB signaling, promoting neuroprotection and synaptic remodeling. This approach offers a promising therapeutic strategy for modifying AD pathology and restoring cognitive function.