Basic Science and Pathogenesis

Area of Science:

• Neuroscience
• Stem Cell Therapy
• Alzheimer's Disease Research

Background:

• Alzheimer's disease (AD) prevalence is increasing, necessitating novel treatments beyond risky disease-modifying therapies.
• Sleep disturbances, including NREM sleep deficits and impaired slow oscillations, are common in AD and linked to disease progression.
• Previous studies identified GABAergic interneuron dysfunction as a cause of sleep deficits in APP/PS1 mouse models of AD.

Purpose of the Study:

• To investigate the survival, integration, and functional impact of transplanted medial ganglionic eminence (MGE) precursors in the APP/PS1 mouse model of Alzheimer's disease.
• To determine if cell therapy can rescue impaired slow oscillations, a key NREM sleep brain rhythm, in APP/PS1 mice.

Main Methods:

• Harvesting and cortical injection of MGE precursors into APP/PS1 mouse brains.
• Utilizing 3D light-sheet microscopy to track cell survival and migration.
• Assessing donor cell maturation and synaptic integration using interneuron and synaptic markers with super-resolution microscopy.
• Evaluating donor interneuron activity via multiphoton calcium imaging.
• Measuring the effect of cell transplantation on slow oscillations using voltage-sensitive dye imaging.

Main Results:

• Transplanted MGE precursors survived, migrated, and matured into functional interneurons within the APP/PS1 host cortex.
• Donor cells formed inhibitory synapses and exhibited calcium transients, indicating successful neural circuit integration.
• Crucially, cell transplantation effectively rescued the impaired slow oscillations in APP/PS1 mice.

Conclusions:

• A single administration of MGE precursors can reverse functional deficits in cortical circuits by restoring sleep-dependent brain rhythms.
• Stem cell therapy presents a promising strategy for treating sleep impairments in Alzheimer's disease and potentially mitigating disease progression.