重组人促红细胞生成素改善小鼠创伤性脑损伤神经功能

Recombinant human erythropoietin improves neurological function after traumatic brain injury of mice

目的探讨重组人促红细胞生成素(rhEPO)对小鼠创伤性脑损伤(TBI)血管生成及神经功能恢复的影响。方法将小鼠随机分为假手术组(sham组)、模型组(TBI组,控制性皮质撞击制作重型TBI模型)和治疗组[EPO组,损伤后连续7 d腹腔注射5000 IU/(kg·d)rhEPO],每组小鼠15只。伤后3、7和14 d进行神经功能缺损评分(mNSS),14 d以Western blot及免疫荧光法检测脑损伤灶周边区域eNOS、VEGF和CD31蛋白表达,并通过CD31+细胞进行微血管密度计数(MVD);21 d以苏木精-伊红(HE)染色大脑切片并检测损伤灶体积。结果伤后3、7及14 d,TBI组较sham组mNSS明显上升(P<0.001),伤后7及14 d EPO组mNSS低于TBI组(P<0.05)。伤后14 d,损伤灶周边区eNOS、VEGF和CD31蛋白的表达,TBI组较sham组升高(P<0.05),EPO组较TBI组升高(P<0.05);TBI组的MVD显著低于sham组(P<0.001),EPO组的MVD显著高于TBI组(P<0.001)。伤后21 d EPO组较TBI组创伤体积减小(P<0.05)。结论rhEPO促进小鼠TBI血管生成,改善颅脑损伤后神经功能。

Objective To investigate the effects of recombinant human erythropoietin(rhEPO)on angiogenesis and neurofunction recovery of mice with traumatic brain injury(TBI).Methods Mice were randomly divided into sham operation group(sham group),traumatic brain injury group(TBI group,severe TBI model made by controlled cortical impact)and rh EPO treatment group(EPO group,rhEPO intraperitoneal injected at 5000 IU/(kg·d)for 7 days after the trauma).Each group included 15 mice.Neurological scores were performed at 3,7,and 14 d using modified neurological severity score(m NSS).Fourteen days after injury,Western blot and immunofluorescence were used to detect the protein expression of eNOS,VEGF and CD31 around ipsilateral cerebral cortex,and the microvessel density(MVD)was detected by CD31+cells.The lesion volume was measured at 21 d after injury using hematoxylin-eosin(HE)stained specimens.Results 3,7 and 14 d after TBI,m NSS of TBI group was significantly higher than that of sham group(P<0.001).7 and 14 d after TBI,m NSS of EPO group was lower than those of TBI group(P<0.05).Fourteen days after TBI,the protein expression of eNOS,VEGF and CD31 was higher in TBI group than those of sham group,and the EPO group was higher than those of TBI group.(P<0.05).14 d after TBI,the MVD of TBI group was significantly lower than sham group(P<0.001),and the MVD of EPO group was significantly higher than TBI group(P<0.001).Twenty one days after injury,the volume of EPO group was reduced compared with TBI group(8.90±1.79)(P<0.05).Conclusions rhEPO promotes angiogenesis and improves neurological function after TBI of mice.