Single-Cell Cortical Transcriptomics Reveals Common and Distinct Changes in Cell-Cell Communication in Alzheimer's...

Area of Science:

• Neuroscience
• Genomics
• Molecular Biology

Background:

• Alzheimer's disease (AD) and Parkinson's disease (PD) are major neurodegenerative disorders causing neuronal loss and functional decline.
• Despite distinct clinical symptoms, AD and PD share molecular pathologies like mitochondrial dysfunction and synaptic degeneration.
• Investigating shared molecular changes at single-cell resolution in the cortex may uncover common disease mechanisms.

Purpose of the Study:

• To compare molecular alterations in the cortex of AD and PD patients versus controls using single-cell transcriptomics.
• To identify shared and distinct gene expression changes, pathway activities, and cell-cell communication events in AD and PD.
• To explore common susceptibility factors and disease mechanisms in these neurodegenerative conditions.

Main Methods:

• Single-cell RNA sequencing (scRNA-seq) of post-mortem cortical tissue from AD, PD, and control subjects.
• Differential gene expression analysis to identify disease-specific and shared molecular changes.
• Pathway analysis and cell-cell communication network analysis to investigate functional alterations.

Main Results:

• Significant disease-specific, shared, and opposing gene expression changes were identified, with cell type-specific signatures for both AD and PD.
• Hypoxia signaling and lipid metabolism were significantly modulated in both diseases, but with contrasting expression patterns.
• Shared alterations in the JAK-STAT signaling pathway, crucial for inflammatory responses, were observed in both AD and PD through pathway and cell-cell communication analyses.

Conclusions:

• The study reveals common and distinct molecular signatures, pathway activities, and gene regulatory subnetworks in Alzheimer's and Parkinson's diseases.
• Coordinated changes in pathway activity and cell-cell communication provide insights into shared pathomechanisms.
• These findings may inform the development of future diagnostics and therapeutics for neurodegenerative disorders.