摘要
目的探讨亚低温对创伤性脑损伤（traumatic brain injury，TBl）海马齿状回颗粒下区神经干细胞（neural stem cells，NSCs）增殖和分化的影响及潜在机制。方法SD大鼠按随机数字表法分为假手术组（只暴露硬脑膜，不接受液压冲击）、亚低温组（假手术组大鼠给予亚低温治疗）、TBI组[采用液压冲击仪（2．4arm）建立sD大鼠单侧重型TBI模型]和TBI＋亚低温组（TBI后即刻给予72h亚低温治疗），每组8只大鼠。TBI模型制备后连续7d行BrdU腹腔注射，1次／d。TBI后第7天断头取损伤侧海马匀浆或40g／L多聚甲醛灌流取材切片，采用免疫组织化学法检测海马齿状回颗粒下区BrdU和双皮质素的表达，选用连续5张切片进行阳性细胞计数。采用Western blot检测海马沉默信息调节因子（silent information regulator1，Sirt1）蛋白的表达量。结果与假手术组比较，TBI组伤后7d海马齿状回颗粒下区Brdu和双皮质素标记细胞数显著增加（P均〈0．01），而TBI＋亚低温组较TBI组BrdU、双皮质素的表达增加[（257．4±34．3）：（196．4±23．8）]、[（346．4±42．2）：（245．7±33．2）]（P〈0．01）。同时亚低温可逆转TBI诱导的海马Sirt1过表达[（0．62±0．08）：（1．18±0．11）]（P〈0．01）。结论亚低温治疗可促进TBI后海马齿状回颗粒下区NSCs的增殖和神经元分化，其机制可能与抑制海马Sirt1蛋白过表达有关。
Objective To investigate the effect of mild hypothermia on proliferation and differentiation of neural stem cells （NGCs） in hippocampal subgranular zone after traumatic brain injury （TBI） and the underlying mechanism. Methods SD rats were divided into shamnjured group （only left dura mater exposed） , hypothermia group （ sham injury ＋ mild hypothermia therapy for 72 hours） , TBI group （unilateral fluid percussion was used to generate severe TBI）, and TBI ＋ hypothermia group （TBI ＋ mild hypothermia therapy for 72 hours） according to the random number table, with 8 rats per group. Hippocampal homogenates or brain tissues were harvested after BrdU （100 mg/kg） was intraperitoneally administered to rats once a day for 7 days postTBI. Expressions of BrdU and double cortin in hippoeampal subgranular zone were respectively detected by immunohistochemical or immunofluorescenee staining. Level of Sirtl （ silence information regulatory proteins, Sirtl ） in hippocampus was detected by Western blot. Results BrdU- and double cortin-positive cells in rat hippocampal subgranular zone greatly increased at 7 days after TBI in comparison with sham-injured group （P 〈0.01 ）. Moreover, BrdU and double cortin in rat hippocampal subgranular zone in TBI ＋ hypothermia group was significantly higher than that in TBI group [ （257.4 ± 34.3 ） vs （ 196.4±23.8） ; （346.4± 42.2） vs （245.7 ± 33.2）, P 〈 0.01 ]. Moreover, mild hypothermia reversed TBI-induced over-expression of Sirtl [ （0.62±0. 075 ） vs （ 1.18 ±0. 11 ）, P 〈 0. 01 ]. Conclusion Mild hypothermia therapy can promote proliferation and neuronal differentiation of NSCs in hippocampal subgranular zone after TBI and the possible mechanism may relate to the inhibition of over-expression of Sirtl.
出处
《中华创伤杂志》
CAS
CSCD
北大核心
2014年第6期500-503,共4页
Chinese Journal of Trauma
基金
国家自然科学基金资助项目（81271392,81341113,81301050）
中国博士后基金资助项目（2013M542583）
武警后勤学院科研创新团队基金资助项目（WHTD201306）
关键词
颅脑损伤
神经干细胞
亚低温
Craniocerebral trauma
Neural stem cells
Mild hypothermia
