Effects of bone marrow mesenchymal stem cells supernatant on hippocampal GFAP expression and learning and memory in rats with neonatal hypoxic ischemic brain damage / 中华行为医学与脑科学杂志

ABSTRACT

Objective To analyze the expression of glial fibrillary acidic protein(GFAP) in hippocampal of rats with hypoxic-ischemic brain damage(HIBD) after injection of bone marrow stromal cells(BMSCs) supernatant into the lateral ventricle of the neonate rats,assess the ability of learning and memory,and explore the mechanism.Methods 7-day-old SD rats were randomly divided into sham operation group,model group,cells and supernatant group,with 20 rats in each group.The HIBD model was established via the ligation of left carotid arteries followed by 2-hour hypoxia.One week later,rats in control group were injected with 0.01 mol/L PBS 2 μl via the left ventricle.Meanwhile,the cell and the supernatant groups were injected with BMSCs and supernatant harvested from BMSC culture,respectively,via the same route.In the sham operation group,the left carotid arteries were separated but not ligated,and no hypoxia treatment was imposed on this group.They also received 0.01 mol/L PBS injection 2 μl per weak post surgery.8 weeks later,Morris water maze test was performed to assess the learning and memory,and the expression of GFAP in the dentate gyrus of rats was measured by immunohistochemistry.Results Morris water maze showed that the searching time of the probe trail(T1(15.40±2.80) s) and reversal probe trail (T2(16.45± 1.16) s) of the model group was shorter than that of the sham operation group (T1(19.96±2.57) s,T2(225.32±2.54)s,P＜0.05),while the searching time of the cell group(T1(17.54± 1.80)s,T2(18.99± 1.47) s) and supernatant group (T1(17.40±2.37) s,T2(17.96± 1.09) s) was prolonged compared with that of the model group (P＜0.05).No significant difference between the cell group and the supernatant group (P＞0.05).The integral optical density (IOD) value of GFAP positive cells was higher in the model group than that in the sham operation group(15.26±1.49 vs 12.82±2.56,P＜0.05),while the IOD of cell group(18.13±1.97) and that of the supernatant group(17.38± 1.64) were higher than that of the model group (P＜0.05).However,there was no significant difference between the cell group and the supernatant group (9＞0.05).Conclusion BMSC supernatant injected through lateral ventricle can improve the HIBD rats' abilities of learning and memory.The mechanism might be that MSCs secrete some cytokines to promote central nervous system repair.