高压氧对大鼠颅脑损伤后海马区神经干细胞增殖分化的影响

The effects of hyperbaric oxygen therapy on proliferation and differentiation of neural stem cells in rats with traumatic brain injury

目的 观察高压氧对大鼠颅脑损伤后神经功能缺损及内源性神经干细胞增殖分化的影响.方法 成年健康Wistar大鼠随机分为假手术组、颅脑损伤组及高压氧治疗组,应用改良的自由落体方法制备脑损伤模型,运用改良大鼠神经功能缺损评分评价损伤前1d、伤后1、7及14d的神经功能,用免疫荧光双标记染色法观察伤后1、7及14 d大鼠海马区神经干细胞增殖分化.结果 在伤前1d和伤后1d时,颅脑损伤组神经功能缺损评分为0和（10.00±1.58）分,高压氧治疗组神经功能缺损评分为0和（10.33±2.13）分,两组比较差异无统计学意义（P＞0.05）,在颅脑损伤后7d和14d时,高压氧治疗组神经功能缺损评分[（4.67±0.84）、（2.85±1.91）分]显著低于颅脑损伤组[（6.32±1.16）、（5.71±0.69）分,P＜0.05];颅脑损伤组和高压氧治疗组海马区5-溴脱氧尿嘧啶核苷（5-BrdU）/巢蛋白（Nestin）双标阳性细胞数,在颅脑损伤后1d为（1.0±0.3）个和（1.2±0.2）个,在伤后7 d[（14.2±1.2）、（22.3±1.5）个]和14 d[（9.6±0.7）、（13.8±1.4）个]均较伤后1d增多,在伤后7d较伤后14d明显增多（P＜0.05）;与颅脑损伤组比较,高压氧治疗组在伤后第7天及第14天双标阳性的细胞数明显增多（P＜0.05）.结论 高压氧能促进颅脑损伤大鼠神经功能缺损恢复,对颅脑损伤后内源性神经干细胞增殖分化有促进作用.

Objective To observe the effects of hyperbaric oxygen therapy on the proliferation and differentiation of endogenous neural stem cells and neurological severity after traumatic brain injury.Methods Adult Wistar rats were randomly divided into sham-operation group,traumatic brain injury group and hyperbaric oxygen therapy group.Animal models of craniocerebral trauma were made using the improved free-fall method in the rats.Neuromotor function of rats was assessed based on the modified neurological severity scores at different times.The proliferation and differentiation of neural stem cells of the brain tissue was detected by 5-bromo 2＆#39;-deoxyuridine （5-BrdU） labeling fluorescence immunocytochemistry at 1st day,7th day and 14th day after injury.Results The neurological severity scores in the traumatic brain injury group were 0 and 10.00 ± 1.58 at 1st day before injury and 1st day after injury.The neurological severity scores in the hyperbaric oxygen therapy group were 0 and 10.33 ± 2.13 at 1 st day before injury and 1st day after injury.The neurological severity scores in the traumatic brain injury group and hyperbaric oxygen therapy group had no statistical difference （P 〉 0.05）.The neurological severity scores （4.67 ±0.84,2.85 ± 1.91） in the hyperbaric oxygen therapy group were significantly lower than those （6.32 ± 1.16,5.71 ± 0.69） in the traumatic brain injury group at 7th day and 14th day after injury （P 〈 0.05）.Only few of 5-BrdU and Nestin positive cells were observed in hippocampus of the traumatic brain injury group （1,0 ± 0.3） and hyperbaric oxygen therapy group （1.2 ± 0.2） at 1 st day after injury.The 5-BrdU and Nestin positive cells of the traumatic brain injury group and hyperbaric oxygen therapy group began to increase from the 7th day （14.2 ±1.2,22.3 ±1.5） to the 14th day （9.6 ±0.7,13.8 ±1.4）.Compared with the 14th day,the 5-BrdU and Nestin positive cells significantly increased in 7th day （P 〈 0.05）.Compared with the traumatic brain injury group,the 5-BrdU and Nestin positive cells significantly increased in the hyperbaric oxygen therapy group at 7th day and 14th day after injury （P 〈 0.05）.Conclusion Hyperbaric oxygen therapy is able to promote the neurological functional recovery of rats after traumatic brain injury.Hyperbaric oxygen therapy can enhance the proliferation and differentiation of endogenous neural stem cells after traumatic brain injury.