# Long-Term Alterations in Motor Skills, Neurogenesis and Astrocyte Numbers following Transient Cerebral Ischemia in Mice

## TL;DR

This study shows that a temporary brain injury in mice leads to long-term changes in motor skills and brain cell activity.

## Contribution

The study reveals long-term effects of transient cerebral ischemia on neurogenesis and astrocyte numbers in mice.

## Key findings

- Mice showed impaired reaching ability for up to six months after transient cerebral ischemia.
- Neuroblast proliferation increased in the ipsilateral SVZ, and astrocyte numbers rose in the hippocampal DG.
- Transient cerebral ischemia triggers a long-lasting regenerative response in specific brain regions.

## Abstract

Background and Objectives. Neurogenesis is an integral process in post-stroke recovery, involving the recruitment of proliferating neuroblasts from neurogenic niches of the mammal brain. However, the role of neurogenesis in the long-term restoration following ischemic stroke is fragmented. Post-stroke motor dysfunction includes challenges in the proper, coordinated use of hands and is present in roughly two-thirds of human patients. In this study, we investigated chronic behavioral and biochemical alterations after transient cerebral ischemia in adult male mice. Materials and Methods: Twelve-week-old C57BL/6N male mice were used, and fMCAo lasting 60 min was induced. At multiple timepoints after fMCAo induction, a single pellet reaching task was performed. Six months after the procedure, we immunohistochemically determined the number of proliferating neuroblasts (BrdU and DCX-positive) and the number of differentiated astrocytes (GFAP-positive) in both brain hemispheres. Results: The reaching ability of fMCAo mice was impaired from one month to six months after the induction of ischemia. Neuroblast proliferation was increased in the ipsilateral SVZ, whereas GFAP+ cell count was elevated in the hippocampal DG of both hemispheres of the fMCAo group mice. Conclusions: Our current report demonstrates the long-term effects of transient cerebral ischemia on mice functional parameters and neurogenesis progression. Our data demonstrate that transient cerebral ischemia promotes a long-lasting regenerative response in the ipsilateral brain hemisphere, specifically in the neurogenic SVZ and DG regions.