骨髓基质干细胞移植对脑挫伤大鼠神经行为学和Bax表达的影响

目的 探讨骨髓基质干细胞(bone morrow stromal cells，BMSCs)移植对脑挫伤大鼠神经功能的影响，并探讨其分子机制。方法 24只SD大鼠按随机数字表法分为假手术组、脑挫伤组（采用自由落体砸伤制备大鼠运动皮质区脑损伤模型）和BMSCs移植组（将培养纯化的BMSCs移植入损伤位点周围），每组8只大鼠。术后对动物进行神经损伤严重程度评分(neurological severity scores，NSS)；14 d后取脑组织观察移植细胞在体内存活、迁移情况；用RT - PCR技术检测宿主脑组织内凋亡基因Bax的表达变化。结果 脑挫伤组NSS为(12±3)分，较BMSCs移植组NSS(7±1)分明显升高(P＜0.05)。移植的BMSCs能在宿主脑内存活并迁移；RT - PCR显示BMSCs移植组凋亡基因Bax表达（0.9±0.1）较脑挫伤组(1.1±0.2)明显减少(P＜0.05)。结论 BMSCs移植能有效促进脑挫伤大鼠神经功能恢复，其作用机制可能与抑制促凋亡基因Bax表达有关。

Effects of bone morrow stromal cells transplantation on neurological behavior and Bax expression in rats with traumatic brain injury

Objective To explore the effects of bone morrow stromal cells (BMSCs) on the neurological behavior of rats with traumatic brain injury (TBI).Methods Twenty-four SD rats were randomly and equally divided into control group, TBI group and BMSC group. The weight-drop device was adapted to establish the TBI model. The injury severity and its outcome were evaluated by a set of criteria termed neurological severity score (NSS). Brain tissues were harvested at day 14 to observe the survival and migration of the transplanted cells. Bax expression was detected by RT-PCR. Results NSS was (12 ±3 ) points in the TBI group, significantly higher than (7 ± 1 ) points in the BMSC group (P ＜0.05). The transplanted BMSCs could survive and migrate. Moreover, BAX, a crucail apopotosis gene, was down-regulated to 0.9 ±0.1 in the BMSC group, compared with 1.1 ±0.2 in the TBI group (P ＜0.05). Conclusions BMSC transplantation is available to improve the neurological function, as may be associated with the Bax.