重组蛋白类药物RT-03对小鼠急性放射性脑损伤的治疗作用

Therapeutic effect of a recombinant protein drug RT-03 on acute radiation-induced brain injury in mice

目的探讨重组蛋白类药物RT-03对小鼠急性放射性脑损伤的治疗作用。方法 100只雄性SPF级C57BL/6小鼠随机分为5组(n=20):正常对照组、照射对照组,以及RT-03 1、5和25μg/kg治疗组。照射小鼠用60Coγ线单次头部照射15 Gy,治疗组在照后24 h腹腔注射RT-03(分别为1、5和25μg/kg),正常对照组和照射对照组给予等体积生理盐水。分别在给药后第7、14和28天进行指标检测,通过旷场实验评估小鼠空间自发探索能力;采用MP-150多导生理记录及分析系统进行脑电生理检测;组织切片HE染色法观察脑组织病理学改变;免疫组化法检测IFN-γ和IL-13等炎症因子的表达。结果与正常对照组相比,照射对照组小鼠总路程显著减少(P<0.01)、中央活动时间显著减少(P<0.05)、给药后3个时间点各组中央路程无显著差异;脑电θ波和δ波功率于给药后3个时间点均上升;照射后可见脑组织嗜酸性变现象,血管周间隙增大;小鼠脑组织中IFN-γ积分光密度显著升高(P<0.01),IL-13表达明显增多(P<0.01)。与照射对照组比较,RT-03治疗后,3个治疗剂量组的中央活动时间延长、总路程和中央路程增多,θ波和δ波功率下降,嗜酸性变现象减少、血管间隙减小,IFN-γ和IL-13积分光密度降低,RT-03 5和25μg/kg治疗组效果更为显著。脑组织病理变化和自发探索行为的改变以给药后第14天最为显著;脑电变化各时间点之间无明显差异;IFN-γ和IL-13的改变以给药后第7天最为显著。结论 RT-03可减轻小鼠急性放射性脑损伤。

Objective To investigate the therapeutic effect of a recombinant protein drug RT-03 on the radiation-induced brain injury. Methods A hundred male SPF grade C57BL/6 mice were randomly divided into five groups(n=20):normal control group,irradiation control group,and RT-03 1,5 and 25 μg/kg treatment groups. Mice were irradiated with 15 Gy60 Co γ-ray on head.Twenty-four hours after irradiation,RT-03(dose of 1,5 and 25 μg/kg,respectively)was administered intraperitoneally. On the 7 d,14 d,and 28 d after administration,the spontaneous exploration ability of mice was evaluated by the open-field test,the electrophysiology of brain was detected by the MP-150 polychannel physiological recording and analysis system,the pathological changes of brain tissue were examined by the HE staining and the expression of inflammatory factors such as interferon γ(IFN-γ)and interleukin 13(IL-13)was detected by immunohistochemistry. Results Compared with the normal control group,the total distance moved(P<0.01)and the time of central activity(P<0.05)were significantly decreased in the irradiation control group. The power of θ wave and δ wave increased at three time points after RT-03 administration. Perivascular space widening and eosinophilia phenomenon in mice′s brain were observed after irradiation. The integral optical density of IFN-γ(P<0.01)and IL-13(P<0.01)was significantly increased. Compared with the irradiation control group,the central activity time in the 1,5 and 25 μg/kg RT-03 groups was prolonged after RT-03 treatment. Also,the total distance and central distance increased,the power of θ wave and δ wave decreased,the eosinophilic changes and the perivascular gap widening were alleviated,and the integrated optical density(IOD)of IFN-γ and IL-13 decreased after administration. These effects were more significant in the 5 and 25 μg/kg RT-03 groups. The changes in the brain tissue and spontaneous exploring behavior were most significant at d14 after RT-03 administration. There was no significant difference in the electroencephalogram(EEG)changes between each of the tested time points. The changes in IFN-γ and IL-13 were the most significant at d7 after RT-03 administration. Conclusion RT-03 could alleviate the radiation-induced brain injury in mice.