Effects of bone marrow mononuclear cell transplantation on the recovery of nerve function after focal cerebral ischemia and reperfusion

Objective To determine the effect of transplanting bone marrow mononuclear cells (BMMCs) on the expression of glial fibrillary acidic protein (GFAP) and Nogo-A around the ischemic foci after focal cerebral ischemia and reperfusion, and to study any role of BMMCs in nerve function recovery. Methods BMMCs were isolated from the bone marrow of Sprague-Dawley rats. Cerebral ischemia and reperfusion was performed using a nylon thread to occlude the right middle cerebral artery for 2h followed by 24h of reperfusion. The qualified models were selected according to the Longa scale. The 48 models selected were randomly divided into a model group and an observation group, each of 24. Each group was further divided into 7d, 14d and 21d subgroups. 100μl of BMMCs (5×106 /ml) were slowly injected into the ischemic lateral striata of the observation group. The rats in the model group were similarly injected, but with buffered saline solution. The rats were evaluated using the Longa scale after 7d, 14d and 21d. The rats were then sacrificed and the brain was resected. Immunohistochemical assays quantified the expression of GFAP and Nogo-A around the ischemic foci. Results Compared with the model group, the rats in the observation group showed less neurological deficit on the 21st day, significantly greater expression of GFAP and significantly less Nogo-A expression on days 14 and 21. Nogo-A expression on the 21st day was also significantly lower than on the 14th day in the observation group. Conclusion BMMC transplantation can promote recovery from nerve damage after focal cerebral ischemia, which is probably related to enhanced expression of GFAP and restrained expression of Nogo-A in the brain tissues surrounding ischemic lesions. Key words: Bone marrow mononuclear cells; cerebral ischemia; Glial fibrillary acidic protein; Nogo-A