Tat-NTS peptide, a cell-penetrating compound, comprises the HIV-1 Tat protein transduction domain fused with a 10-amino acid sequence (residues 228-237) from the repeat III domain of annexin A1, serving as a nuclear translocation signal (NTS). This peptide hinders the interaction between annexin A1 and importin β, obstructing annexin A1's nuclear entry in primary mouse hippocampal neurons. Tat-NTS effectively prevents apoptosis triggered by glucose-oxygen deprivation and reperfusion in these neurons. When administered in vivo at a dosage of 10 mg/kg, it significantly reduces infarct size, minimizes neuronal apoptosis, and improves navigation performance in the Morris water maze test for mice subjected to ischemia-reperfusion injury via middle cerebral artery occlusion (MCAO).