单唾液酸四己糖神经节苷脂钠对大鼠创伤性脑损伤的保护作用

Protective effect of monosialotetrahexosylganglioside sodium on traumatic brain injury in rats

目的探讨单唾液酸四己糖神经节苷脂钠(GM1)对大鼠创伤性脑损伤(TBI)的保护作用及可能机制。方法30只SD大鼠按随机数字表法分为对照组、生理盐水组和GM1组,各10只。对照组大鼠颅骨只开骨窗不制备TBI模型,余两组大鼠颅骨开骨窗后应用液压可控损伤装置制备TBI模型,三组大鼠连续5 d腹腔注射5-溴脱氧尿嘧啶核苷(BrdU)以标记新生的神经细胞。对照组和生理盐水组大鼠连续10 d尾静脉注射无菌生理盐水1 ml/d,GM1组大鼠连续14 d尾静脉注射GM1注射液5 mg·kg-1·d-1。颅骨开骨窗后11 d开始连续5 d Morris水迷宫实验。然后大鼠灌注取脑行冰冻切片,应用TUNEL试剂盒检测大鼠皮质细胞凋亡情况,应用NeuN/BrdU免疫荧光双标检测皮质新生神经元情况。结果三组大鼠逃避潜伏期和平台穿越次数比较均有统计学差异(P<0. 01),逃避潜伏期对照组 GM1组>生理盐水组。TUNEL检测结果显示,对照组大鼠大脑皮质几乎未见凋亡细胞,GM1组大鼠大脑皮质可见少量凋亡细胞,生理盐水组大鼠大脑皮质可见较多凋亡细胞,组间差异有统计学意义(P<0. 05)。NeuN/BrdU免疫荧光双标检测结果显示,对照组大鼠大脑皮质未见NeuN+/BrdU+的新生神经元,生理盐水组大鼠大脑皮质可见较少的NeuN+/BrdU+的新生神经元,GM1组大鼠大脑皮质可见较多的NeuN+/BrdU+的新生神经元,组间差异有统计学意义(P<0. 05)。结论 GM1或可保护损伤的大脑皮质细胞免予凋亡,同时促进损伤皮质内源性神经元的发生,能够促进TBI大鼠学习记忆等认知功能的改善。

Objective To investigate the protective effect and mechanism of monosialotetrahexosylganglioside sodium(GM1) on traumatic brain injury(TBI) in rats. Methods A total of 30 SD rats were divided into control group,NS group and GM1 group according to the random number table(n = 10,each). In the control group,the rats were only openind skell window without TBI model prepared,while in the other two groups,TBI model was made by hydraulic controlled injury device. In three groups,BrdU was injected intraperitoneally for 5 days continuously to mark the newborn nerve cells. The rats in the control group and NS group were injected with 1 ml/d sterile normal saline for 10 days,and the rats in GM1 group were injected with 5 mg·kg-1·d-1 GM1 for 14 days. At 11th day after opening skell window,the Morris water maze was carried out for 5 days. Then the rats were perfused and the brains were frozen. The apoptosis of cortical cells was detected by TUNEL kit,and the neoneurons in corter were detected by NeuN/BrdU double immunofluorescence. Results There were significant differences in escape latency and platform crossing times among the three groups(P< 0. 01). The escape latency increased in the order of control group,GM1 group and NS group,and the number of platform crossing decreased in the order of control group,GM1 group and NS group. The results of TUNEL showed that there were barely apoptotic cells in the cerebral cortex of the control group,a small number of apoptotic cells in the GM1 group,and more apoptotic cells in the NS group(P< 0. 05). The results of NeuN/BrdU double immunofluorescence showed that there were no NeuN+/BrdU+ neoneurons in cortex of the control group,less NeuN+/BrdU+ newborn neurons in cortex of the NS group,and more NeuN+/BrdU+ neoneurons in cortex of the GM1 group. Conclusion GM1 may protect the injured cortical cells from apoptosis,promote the development of endogenous neurons in the injured cortex,and improve the cognitive function(such as learning and memory) of TBI rats.