ABSTRACT
Objective To investigate the effects of bone mesenchymal stem cell (BMSC) transplantation on neuronal nuclei (NeuN) and neurogenin 1 (Ngnl) in focal cerebral ischemic rats.Methods A total of 64 healthy adult male Sprague-Dawley rats were randomly divided into normal (N) + phosphate-buffered solution (PBS),middle cerebral occlusion (MCAO)+ PBS,N + BMSC and MCAO + BMSC groups (n =16 in each group).A rat model was induced by the intraluminal suture method.BMSC was cultured in vitro.At 24 h after modeling,brain transplantation was conducted.Magnetic resonance imaging (MRI) was used to detect infarct volume in vivo.NeuN/DAP,Ngnl/DAPIimmunofluorescence double-labeling and Western blot were used to detect the expression of NeuN and Ngnl around ischemic brain tissue.Results On day 14 after transplantation,the T1-and T2-weighted imaging revealed that the cerebral cortex and striatum had abnormal signal areas in the rats of the MCAO group.The infarct volume of the MCAO + BMSC group was significantly less than that of the MCAO + PBS group (32.5％ ± 4.2％ vs.47.9％ ± 7.9％ ; P ＜ 0.01).Immunofluorescence doublelabeling assay showed that the numbers of cells of NeuN+/DAPI+ (976.2 ± 87.5/mm2 vs.1 908.3 ±127.8/mm2; P ＜ 0.01) and Ngn1 +/DAPI + (251.6 ± 23.1/rmm2 vs.285.1 ± 25.2/mm2 ; P ＜ 0.01) of the MCAO + PBS group were significantly less than those of the N + PBS group,but those of NeuN+/DAPI +(1 439.9 ± 101.7/mm2; P ＜ 0.01) and Ngn1 +/DAPI + (356.3 ± 35.6/mm2; P ＜ 0.01) of the MCAO + BMSC group were significantly more than the MCAO + PBS group.Western blot analysis showed that the protein expression levels of NeuN (0.69 ±0.06 vs.0.91 ±0.09; P ＜0.01) and Ngn1 (0.53 ±0.05 vs.0.62 ±0.07;P ＜0.01) of the MCAO +PBS group were significantly lower than those of the N +PBS group,but those of NeuN (0.82 ± 0.07; P ＜ 0.01) and Ngn1 (0.77 ± 0.09; P ＜ 0.01) of the MCAO + BMSC group were significantly higher than the MCAO + PBS group.Conclusions BMSC transplantation may promote the expression of NeuN and Ngn1,and alleviate MCAO caused brain injury.