Molecular basis of Gray Matter Volume Alterations in Ipsilesional and Contralesional Hemispheres after Subcortical Stroke

Motivation: The molecular basis underlying differences between the ipsilesional and contralesional hemispheres in structural alterations after stroke remains unclear. Goal(s): We aimed to investigate the molecular basis of differences between the ipsilesional and contralesional hemispheres in structure after stroke. Approach: Gray matter volume (GMV) data from stroke patients were integrated with transcriptional data from the Allen Human Brain Atlas. Correlations between GMV changes and gene expression were analyzed, followed by gene enrichment and cell-type-specific analyses. Results: Ipsilesional GMV decreases were linked to cellular stress and immune responses, while contralesional GMV increases were associated with synaptic and axon development, with specific ties to excitatory cells. Impact: Our findings demonstrate that contralesional increase and ipsilesional decrease in the GMV after stroke were linked to different molecular pathways and cellular types. These findings provide new insights into understanding brain damage and compensatory mechanisms after stroke.