人脐带沃顿胶间充质干细胞移植对创伤性脑损伤大鼠脑损伤区微循环的影响

Effects of mesenchymal stromal cells derived from Wharton＇s jelly cells transplantation on microcirculation in brain damage zone of rats with traumatic brain injury

目的探讨人脐带沃顿胶间充质干细胞（WJCs）对脑创伤区周围微循环的影响。方法72只健康SD大鼠采用随机数字表法分为4组：（1）假手术组；（2）移植对照组；（3）WJCs移植组；（4）正常组。每组18只。移植对照组和WJCs移植组采用Feeney自由落体硬脑膜外撞击法建立中度创伤性颅脑损伤模型，再分别注射0．3mL的生理盐水和WJCs混悬液；假手术组颅骨钻孔后不损伤脑组织不移植细胞；正常组不做任何处理。分别于移植后3d及7d进行大鼠行为学评分；取移植后1d、3d、7d和2周的脑组织切片行免疫组织化学检测，检测大鼠损伤灶周围血管内皮生长因子（VEGF）及CD34的表达；实时定量PCR（RT．PCR）检测的VEGFmRNA表达；测定微血管面密度（MVD）；移植后2周和4周行免疫组化观察胶质纤维酸性蛋白（GFAP）和神经元特异性烯醇化酶（NSE）蛋白表达水平。结果移植后7d，WJCs移植组大鼠mNSS评分明显高于移植对照组，差异有统计学意义（P〈0．05）。WJCs移植组移植后3d、7d和2周损伤灶周围皮层脑组织VEGF和CD34的表达均高于移植对照组，差异有统计学意义（P〈0．05）。移植后2周和4周WJCs移植组损伤区免疫组织化学染色均发现GFAP和NSE阳性细胞，其他3组均未发现．RT—PCR检测到WJCs组VEGFmRNA的表达量高于移植对照组，差异有统计学意义（P〈0．05）。结论WJCs移植后可增加损伤区脑组织VEGF及CD34阳性表达，参与调控损伤区微血管的变化，改善损伤区的微循环．促进大鼠神经功能的恢复。

Objective To observe the effects of mesenchymal stromal cells derived from Wharton＇s jelly cells （WJCs） transplantation on microcirculation in brain damage zone of rats with traumatic brain injury （TBI）. Methods Seventy-two healthy SD rats were randomly divided into sham-operated group, transplanted control group, WJCs transplantation group and normal group （n=l 8）. Feeney＇ s free fall method was employed to induce the TBI models in the transplanted control group and WJCs transplantation group; rats in the sham-operated group only performed skull drilling without TBI or transplantation. Three and 7 d after transplantation, the behavior of rats was scored; 1 and 3 d, and 1 and 2 weeks after transplantation, immunohistochemical staining was used to observe the expressions of vascular endothelial growth factor （VEGF） and CD34 around the focus of damage in rats brain tissue slice; determination of micro-vessel density （MVD） was also measured; 2 and 4 weeks after transplantation, the glial fibrillary acidic portein （GFAP） and NSE protein levels were observed by immunohistochemical staining. Results Seven d after transplantation, the mNSS scores in the WJCs transplantation group was significantly higher than those in the transpanted control group （P〈0.05）; 3 d, and 1 and 2 weeks after transplantation, both the VEGF and CD34 expressions in the cerebral cortex around the lesion in the WJCs transplantation group were significantly higher than those in the transplanted control group （P〈 0.05）; 2 and 4 weeks after transplantation, GFAP and NSE positive cells were discovered in the damaged zone ofWJCs transplantion group by immunohistochemical staining, but not in the other three groups. PCR also showed that VEGF mRNA expression level in the WJCs transplanted group was higher than that in the transplanted control group （P〈0.05）. Conclusion WJCs transplantation can increase the VEGF and CD34 expressions in the brain tissues, participate in the regulation of the changes of capillary in the damaged zone and promote the recovery of behavior of rats.