An Integrative Analysis of Identified Schizophrenia-Associated Brain Cell Types and Gene Expression Changes

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• Schizophrenia (SCZ) is a severe mental disorder characterized by hallucinations, delusions, and disordered thinking.
• The specific contribution of individual brain cell types to SCZ pathogenesis remains poorly understood.

Purpose of the Study:

• To investigate SCZ-associated alterations in brain cell type proportions and gene expression.
• To identify specific cell types and molecular pathways involved in SCZ.

Main Methods:

• Utilized human dorsolateral prefrontal cortex bulk RNA-seq data.
• Employed the CIBERSORTx algorithm for RNA-seq deconvolution to generate single-cell data.
• Analyzed cell type proportions and gene expression patterns in SCZ versus control samples.

Main Results:

• Observed significant differences in brain cell type proportions in SCZ, with increased astrocytes, pericytes, and PAX6 cells, and decreased L5/6_IT_CAR3 and LAMP5 cells.
• Identified dysregulation of chemical synaptic transmission in PVALB and LAMP5 GABAergic neurons.
• Found involvement of immune reactions in SST GABAergic neurons and non-neuronal cells (endothelial, oligodendrocyte).
• Detected cell-type-specific abnormalities in gene expression for molecules relevant to SCZ.
• Identified two major coordinated transcriptomic changes across SCZ-related cell types.

Conclusions:

• SCZ is associated with distinct changes in brain cell type composition.
• Specific neuronal and non-neuronal cell types exhibit SCZ-related transcriptomic alterations.
• These findings provide novel insights into the cellular heterogeneity and molecular mechanisms underlying schizophrenia.