Activated microglia transplantation improves the neural function following acute cerebral infarction in mice / 中国组织工程研究

ABSTRACT

BACKGROUND: Microglia play an important role in immune surveillance in their quiescent state, but the role of the activated microglia is under discussion. OBJECTIVE: To analyze the mechanism of activated microglia in acute cerebral infarction. METHODS: Totally 96 male Kunming mice were selected and randomly divided into four groups, including transplantation, placebo, blank control and sham operation groups. Permanent occlusion of the middle cerebral artery was performed using suture method in the mice of the transplantation, placebo and blank control groups, followed by injection of microglia suspension via subclavian vein, medium containing the same volume of microglia, and nothing, respectively, at 12 hours after modeling. In the meanwhile, the same amount of microglia suspension was injected into the mice of the sham operation group. The Zea-longa scale and brain-derived neurotrophic factor expression at 12, 24 and 72 hours after modeling, the volume of cerebral infarction and the number of nerve cells positive for microtubule-associated protein-2 at 72 hours after modeling were detected. RESULTS AND CONCLUSION: The Zea-longa scale score was 0 point in the sham operation group, which was significantly lower than that in the other three groups at each time point after modeling (P < 0.01). The Zea-longa scores in the transplantation group were significantly lower than those in the placebo and blank control groups at 24 and 72 hours after transplantation (P < 0.01). The positive expression rate of brain-derived neurotrophic factor in the transplantation group was significantly higher than that in the other three groups after transplantation (P < 0.01). The sham group showed no infarction, while the size of cerebral infarction in the transplantation group was significantly lower than that in the placebo and blank control groups (P < 0.01), and the microtubule-associated protein-2 positive rate was significantly higher than that in the placebo and blank control groups (P < 0.01). These results manifest that the activated microglia can improve the survival rate of nerve cells, promote the recovery of cerebral nerve function and reduce the size of cerebral infarction.