脂肪来源神经干细胞移植局灶性脑缺血模型大鼠的血管新生

摘要

BACKGROUND: Adipose tissue-derived neural stem cells transplantation may improve neurological function in rats with cerebral ischemia injury, but its mechanism remains unclear.OBJECTIVE: To study the effects of human adipose tissue-derived neural stem cells transplantation on angiogenesis in rats after focal cerebral ischemia.METHODS: Adipose tissue-derived stromal cells cultured in vitro were differentiated into neural stem cells. A total of 60 healthy male Sprague-Dawley rats were assigned into four groups randomly: normal control group (n=6), sham-operated group (n=6),ischemia control group (n=24) and transplantation treated group (n=24). Models of 2-hour ischemia/reperfusion of rat middle cerebral artery were established by suture-occluded method in the ischemia control group and transplantation treated group.lschemia control group and transplantation treated group were divided randomly into 7, 14, 21 and 28 days reperfusion groups (n=6). Middle cerebral artery was not occluded in the sham-operated group. On hour 24 following model induction, human adipose tissue-derived neural stem cell suspension (2×109 /L) was given in the transplantation treated group via the caudal vein.Saline was injected into the rats in ischemia control group via the caudal vein. Immunohistochemistry was used to identify microvessel density (MVD). The blood vessel proliferation in the rat focal cerebral ischemia area was observed.RESULTS AND CONCLUSION : Immunohistochemistry results have exhibited that compared with the ischemia control group,the MVD was significantly greater at 7, 14, 21, 28 days after transplantation in the transplantation treated group (P ＜ 0.05-0.01).Results indicated that neural stem cells differentiated from human adipose tissue-derived stromal cells transplantation can promote the angiogenesis in cerebral ischemia regions.%背景:脂肪组织来源的神经干细胞移植可改善脑缺血大鼠神经功能,但其机制尚不明确.目的:观察人脂肪组织来源神经干细胞移植对大鼠局灶性脑缺血后血管新生的影响.方法:体外培养脂肪基质细胞,诱导分化为神经干细胞.60只健康雄性SD大鼠分为4组:正常组6只,假手术组6只,缺血对照组24只,移植治疗组24只.后两组线栓法制作大鼠大脑中动脉缺血2 h再灌注模型,又分为缺血2 h再灌注7,14,21,28 d组,每个时点各6只.假手术组不闭塞大脑中动脉.造模成功后24 h,移植治疗组经尾静脉移植人脂肪组织来源神经干细胞悬液,细胞浓度为2×109 L-1;缺血对照组经尾静脉注射生理盐水.免疫组织化学法进行微血管密度计数,观察脑缺血区血管增生情况.结果与结论:免疫组织化学结果显示,与缺血对照组比较,移植治疗组缺血2 h再灌注7,14,21,28 d的微血管密度值均显著高于缺血对照组,差异有显著性意义(P < 0.05～0.01).提示脂肪组织来源的神经干细胞移植可促进脑缺血区新生血管的形成.