Grafting neural stem cells improve the impaired cognitive deficits and spatial recognition after ischemic-hypoxic brain damage in neonatal rats / 中国病理生理杂志

ABSTRACT

AIM: To investigate whether grafting neural stem cells (NSCs) improves the impaired cognitive deficits and spatial recognition after ischemic-hypoxic brain damage (HIBD) in neonatal rats. METHODS: Non-immunosuppressed 7-day-old SD rats were used as research subject and randomly divided into 3 groups (1) sham group (n=10); (2) HIBD group (n=11); (3) transplant group (n=13). (2) and (3) were anesthetized and subjected to a hypoxic/ischemic injury obtained by combination of left carotid ligation and exposure to 8% oxygen for 2 h. At 3 days post injury, hypoxic-ischemic brain damaged animals were re-anesthetized and randomized to receive stereotactic injection of NSCs prelabeling with BrdU or control media into the hippocampus in the ipsilateral hemisphere. Cognitive (i.e., learning) deficits were assessed at 2 to 4 weeks after transplantation. At the end of the behavioral tests, the animals were killed and evaluated for NSC survival and histopathological analysis. RESULTS: Transplant group showed significantly improved cognitive function in selected tests as compared with HIBD group during the 4-week observation period. They took less time than HIBD group in finding the 3 arms baited with water and had a decreased number of working and reference memory errors in radial maze acquisition tests. Histological analysis showed that transplanted NSCs attenuated CA1 cell loss after HIBD, and NSCs survived for as long as 4 weeks after transplantation and were detected in the hippocampus. CONCLUSION: These data suggest that transplanted NSCs attenuate brain damage and cognitive dysfunction after hypoxic-ischemic brain damage. This approach warrants continued investigation in light of potential therapeutic uses.