Decoding hippocampal subfield and glial responses in ischemia using single-cell transcriptomics

Donghee Kwak1, Ji Hyun Park2, Yun Hak Kim3,4

  • 1Convergence Medical Sciences, Pusan National University, Yangsan, Republic of Korea.

Insights

Stroke impacts brain regions differently. This study reveals unique glial and vascular cell responses in the hippocampus after ischemic stroke, offering new therapeutic targets for stroke recovery.

Area of Science:

  • Neuroscience
  • Cell Biology
  • Ischemic Stroke Research

Background:

  • Stroke affects millions globally, causing significant physical and cognitive deficits.
  • The brain's peri-infarct zone, including glial and vascular cells, influences stroke progression.
  • The hippocampus shows regional vulnerability, with CA1 being highly susceptible to ischemia.

Purpose of the Study:

  • To investigate cellular and molecular changes in hippocampal subregions post-ischemia.
  • To differentiate glial and vascular cell responses in CA1 versus CA3-DG regions after stroke.
  • To understand regional variations in the brain's response to global cerebral ischemia.

Main Methods:

  • Single-cell RNA sequencing was performed on Sprague-Dawley rats.
  • A four-vessel occlusion (4-VO) model induced transient global cerebral ischemia.
  • Hippocampal CA1 and CA3-DG regions were analyzed in ischemic and sham-operated rats.

Main Results:

  • Pro-inflammatory microglial subtypes increased post-stroke, with region-specific pathway alterations.
  • A novel oligodendrocyte subtype appeared in the ischemic hippocampus.
  • cd74-positive pericytes increased in the CA3-DG subfield following ischemia.

Conclusions:

  • Global cerebral ischemia induces diverse molecular signatures in hippocampal cells.
  • Glial heterogeneity contributes to regional differences in stroke vulnerability.
  • Findings offer insights into glial and vascular roles in stroke pathology and potential therapeutic strategies.
Abstract