舱室内颅脑爆震伤后大鼠血清生物标志物的变化及其临床意义

Changes of serum biomarkers in rats after blast-induced traumatic brain injury in cabin and the related clinical significance

目的探讨舱室内轻型颅脑爆震伤(bTBI)后早期相关血清生物标志物的变化。方法起爆器引爆模拟舱室内的点爆源,建立舱室内爆炸冲击波致伤的大鼠bTBI模型。选择成年雄性SD大鼠24只,按随机数字表法分为正常对照组(6只)和bTBI组(18只),bTBI组又分为3,24,72 h亚组,每亚组6只。爆炸过程中测量大鼠头部的冲击波压力变化;于bTBI后3,24,72 h观察爆后大鼠的一般状况;心脏穿刺取血,之后迅速断头取脑,对各组大鼠的脑组织行大体观察;HE染色观察海马CA1区神经细胞的损伤情况;留取血清用于检测血清中白细胞介素-6(IL-6)、神经元特异烯醇化酶(NSE)、中枢神经特异蛋白(S100-β)、αⅡ-血影蛋白分解产物-145(SBDP-145)和Tau蛋白水平变化。结果大鼠头部冲击波压力曲线最大峰值为(818.2±33.3)kPa,持续时间约为1 000 μs。爆后大鼠的活跃程度明显下降,被毛无光泽,食欲下降。大体观察可见脑组织明显肿胀,脑表面血管增粗,部分有少量的斑片状出血,但未见明显的脑挫裂伤。HE染色可见大鼠海马CA1区的部分神经细胞发生凋亡或坏死。血清IL-6在bTBI 3,24,72 h亚组分别为(155.3±10.7)pg/ml、(171.3±25.3)pg/ml和(155.6±18.2)pg/ml,均较正常对照组[(116.3±7.3)pg/ml]明显升高(P<0.05);NSE在bTBI 3,24,72 h亚组分别为(12.0±1.0)ng/ml、(11.0±1.0)ng/ml和(11.0±1.2)ng/ml,均较正常对照组[(8.1±0.5)ng/ml]明显升高(P<0.05);S100-β在bTBI 3,24,72 h亚组分别为(71.9±10.7)pg/ml、(58.0±11.5)pg/ml和(56.5±12.2)pg/ml,均较正常对照组[(35.2±2.5)pg/ml]明显升高(P<0.05);SBDP-145在bTBI 3,24,72 h亚组分别为(29.4±2.8)ng/ml、(24.5±4.8)ng/ml和(20.7±2.1)ng/ml,仅bTBI 3 h亚组较正常对照组[(20.9±1.2)ng/ml]明显升高(P<0.05);Tau在bTBI 3,24,72 h亚组分别为(141.4±11.7)pg/ml、(189.5±28.2)pg/ml和(179.1±32.5)pg/ml,较正常对照组[(97.8±5.9)pg/ml]明显升高(P<0.05)。结论轻型bTBI大鼠的血清IL-6、NSE、S100-β、SBDP-145及Tau水平在早期呈不同程度上升,可为血清标志物用于轻型bTBI的早期诊断提供理论基础。

Objective To investigate the early changes of serum biomarkers in rats with mild blast-induced traumatic brain injury (bTBI) in cabin. Methods Explosion source in the simulated cabin was detonated by initiator. The bTBI rat models caused by explosion shock wave in cabin were established. A total of 24 adult male Sprague-Dawley rats were divided into normal control group (n=6) and bTBI group (n=18), according to the random number table. Rats in bTBI group were subdivided at 3, 24, and 72 h post-blast, with 6 rats at each time point. Shock wave pressure at the rat head was measured during the explosion. At 3, 24,and 72 h post-blast, the general condition of rats was observed. Rat blood was collected by cardiac puncture. Then brains were taken completely and quickly for pathological observation. HE staining was used to observe the changes of neurons in hippocampal CA1 area. The collected serum was tested for levels of biomarkers, including interleukin 6 (IL-6), neuron specific enolase(NSE), S100-β, alpha Ⅱ spectrin breakdown product 145 (SBDP-145) and Tau. Results The maximum peak value of the shock wave pressure curve at the rat head was (818.2±33.3)kPa, and the duration was about 1 000 μs. After the explosion, the activity of the rats decreased significantly, the hair was dull, and the appetite decreased. General observation showed that the brain tissue was obviously swollen, the blood vessels on the brain surface were thickened, and there was a little patchy bleeding, but no obvious brain contusion was seen. HE staining showed that some neurons in the hippocampus CA1 area had apoptosis or necrosis. At 3, 24,and 72 hours post-blast, the levels of IL-6 were (155.3±10.7)pg/ml, (171.3±25.3)pg/ml and (155.6±18.2)pg/ml, all of which were significantly higher than that in normal control group [(116.3±7.3)pg/ml](P<0.05);the levels of NSE were (12.0±1.0)ng/ml, (11.0±1.0)ng/ml and (11.0±1.2)ng/ml, all of which were significantly higher than that in normal control group [(8.1±0.5)ng/ml](P<0.05);the levels of S100-β were (71.9±10.7)pg/ml, (58.0±11.5)pg/ml and (56.5±12.2)pg/ml, all of which were significantly higher than that in normal control group [(35.2±2.5)pg/ml] (P<0.05);the levels of SBDP-145 were (29.4±2.8)ng/ml, (24.5±4.8)ng/ml and (20.7±2.1)ng/ml, and only the level at 3 h post-blast was significantly higher than that in normal control group [(20.9±1.2)ng/ml](P<0.05);the levels of Tau were (141.4±11.7)pg/ml, (189.5±28.2)pg/ml and (179.1±32.5)pg/ml,all of which were significantly higher than that in normal control group [(97.8±5.9)pg/ml](P<0.05). Conclusion The serum levels of IL-6, NSE, S100-β, SBDP-145 and Tau in mild bTBI rats increase in various degrees at early time, which provides a theoretical basis for use of serum markers in the early diagnosis of mild bTBI.