创伤性脑损伤合并放射复合伤后损伤区皮层的自噬水平变化及其意义  

Changes of autophagy in injured cortex after trauma and radiation injury of brain

作　　者：万志平[1] 骆纯[1] 谢天浩[1] 钱俊[1] 张磊[1] 叶晶亮[1] 陈峰[1] 朱俊乐[1] 

机构地区：[1]第二军医大学长征医院神经外科,上海200001

出　　处：《中华创伤杂志》2015年第7期651-654,共4页Chinese Journal of Trauma

基　　金：“十二五”全军医学科研面上资助项目（CWS12J089）

摘　　要：目的 探讨皮层神经细胞在创伤性脑损伤合并放射复合伤（TRI）后自噬相关蛋白表达及意义.方法 58只SD雄性成年大鼠按随机数字表法分为假手术组（15只）、单纯创伤性脑损伤（TBI）组（15只）、单纯放射性脑损伤（RBI）组（14只）和TRI组（14只）.TBI组为通过液压致侧方液压皮层损伤;RBI组接受60Co全身单次4.5Gy照射;TRI组皮层液压损伤模型制备成功后30 min内接受60Co全身单次4.5Gy照射.各组模型制备成功后6周采用HE染色检测皮层神经细胞损伤情况;Western blot印迹法检测微管相关蛋白1轻链3-Ⅱ（LC3-Ⅱ）及自噬相关蛋白Beclin-1的表达.结果 TBI组损伤区皮层神经细胞数目为（68.7±7.8）个,较假手术组（96.9±9.6）个减少（P＜0.05）.TBI组出现较明显核固缩和溶解,无明显空泡,LC3-Ⅱ表达增加（P＜0.05）.RBI组神经细胞数目为（59.3±7.4）个,较假手术组减少（P＜0.05）,与TBI组差异无统计学意义（P＞0.05）.RBI组神经细胞无空泡变性,核固缩、溶解不明显.与假手术组、TBI组比较,RBI组Beclin-1和LC3-Ⅱ明显增加（P＜0.01）.TRI组神经细胞数目为（45.8±7.8）个较TBI、RBI组明显减少（P＜0.05）,且空泡变性增多,胞核固缩、溶解明显,LC3-Ⅱ与Beclin-1表达量明显下降（P＜0.01）.结论 TBI及RBI后,损伤区皮层自噬水平提高,而当TBI合并RBI后,损伤“叠加”,皮层神经细胞自噬水平明显下降,伴随细胞变性死亡增加,提示自噬在脑损伤中起保护作用.Objective To clarify the expression of autophagy related proteins in cortical neurons following trauma combined with radiation injury of brain （TRI） and the underlying clinical significance.Methods Fifty-eight male SD adult rats were divided into sham group （n =15）,traumatic brain injury group （TBI group,n =15）,radiation-induced brain injury group （RBI group,n =14）,and TRI group （n =14）,according to the random number table.Rats in TBI group were subjected to lateral fluid percussion injury in the cortex,in RBI group whole body 4.5 Gy single dose irradiation to 60Co,and in TRI group whole body 4.5 Gy single dose irradiation to 60Co within 30 minutes after the lateral fluid percussion injury in the cortex.Six weeks after the modeling in each group,neuronal injury was detected with HE staining and expressions of autophagy-related proteins,LC3-Ⅱ and Beclin-1,were detected through Western blotting.Results TBI group cortical neurons was reduced compared to sham group [（68.7 ± 7.8） vs （96.9 ± 9.6）] （P 〈 0.05）,neuronal pyknosis and dissolution but no obvious vacuoles were seen,and expression of LC3-Ⅱ increased compared to sham group （P 〈 0.05）.In RBI group number of cortical neurons was 59.3 ± 7.4 less than that in CTR group （P 〈 0.05） but not significantly different from that in TBI group （P 〉 0.05）,vacuoles,pyknosis and dissolution were not obvious,and expressions of Beclin-1 and LC3-Ⅱ were significantly increased in contrast with sham and TBI groups （P 〈0.01）.In TRI group number of cortical was grossly reduced to 45.8 ±7.8 in contrast with TBI and RBI groups （P 〈 0.05）,vacuoles,pyknosis and dissolution were obvious,expressions of Beclin-1 and LC3-Ⅱ decreased significantly as compared to TBI and RBI groups （P 〈0.01）.Conclusion Autophagy in the injured cortex is increased after the separate TBI or RBI,but the combined injury of TRI results in significantly reduced autophagy in the injured cortex along with increased neuron degeneration whi

关 键 词：脑损伤 辐射损伤 自噬 

分 类 号：R651.15[医药卫生—外科学]