ABSTRACT
Objective:To observe the dynamic of neurological severity scores (NSS) and the expressions of Wnt/β-catenin signaling pathway, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in rats with severe traumatic brain injury (sTBI), and to explore the effect of Huoxue Huayu decoction.Methods:A total of 126 Sprague-Dawley (SD) rats were randomly divided into seven groups by random number table with 18 rats in each group, namely control group (normal saline 2 kg/L), model group (normal saline 2 kg/L), brain protolysate group (BP group, 5.6 g/kg), Taohong Siwu decoction group (TH group, 10.2 g/kg), Xuefu Zhuyu decoction group (XF group, 15.6 g/kg), Tongqiao Huoxue decoction group (TQ group, 9.6 g/kg) and Buyang Huanwu decoction group (BY group, 28.7 g/kg). The sTBI rat model was reproduced by modified Feeney free fall method, and the rats in the control group were not treated with trauma. The rats in each group were intragastrical administered with corresponding drugs at 6 hours after injury, and the NSS scores were evaluated on the 1st, 3rd and 7th days after injury. After the hippocampus was harvested, the mRNA expressions of Wnt3a and β-catenin were detected by reverse transcription-polymerase chain reaction (RT-PCR), and the positive expressions of BDNF and NGF were detected by immunohistochemistry.Results:Compared with the control group, the rats in the model group showed obvious symptoms of craniocerebral injury at 1 day after injury, which was manifested as significantly increased NSS score, up-regulated mRNA expressions of Wnt3a and β-catenin, and increased positive expressions of BDNF and NGF, which indicated that the sTBI rat model was successfully prepared and presented a certain self-repair ability with the extension of time. Compared with the model group, NSS scores in the XF group, TQ group and BY group significantly decreased at 1 day after injury (6.6±1.5, 6.1±2.0, 5.7±2.4 vs. 9.4±1.5, all P < 0.05); however, the NSS scores in the BP group and TH group decreased significantly at 7 days after injury, and the NSS scores in the TQ group and BY group decreased more significantly than those in other drug groups. Compared with the model group, mRNA expressions of Wnt3a and β-catenin in the hippocampus of the BP group increased significantly at 1 day and 3 days after injury, respectively, and continued to increase with the extension of time. The mRNA expression levels of Wnt3a and β-catenin in the four groups of Huoxue Huayu decoction fluctuated to varying degrees from 1 day to 3 days after injury, but they were significantly higher than those in the model group at 7 days after injury, and the increase was more significant in the BY group [Wnt3a mRNA (2 -ΔΔCt): 154.7±4.1 vs. 17.4±1.0, β-catenin mRNA (2 -ΔΔCt): 17.05±0.45 vs. 2.74±0.13, both P < 0.05], and the second was the TQ group [Wnt3a mRNA (2 -ΔΔCt): 126.6±2.8 vs. 17.4±1.0, β-catenin mRNA (2 -ΔΔCt): 8.70±1.19 vs. 2.74±0.13, both P < 0.05]. Compared with the model group, the positive expressions of BDNF and NGF in the BP group increased significantly at 1 day after injury, but decreased after 3 days after peak. The positive expressions of BDNF and NGF in the four Huoxue Huayu decoction groups fluctuated to varying degrees from 1 day to 3 days after injury, but they were significantly higher than those in the model group at 7 days after injury, among which, the positive expressions of BDNF and NGF in the TQ group and BY group were significantly higher than those in the model group at 1 day after injury [BDNF positive cells (cells/MP): 56.4±6.2, 61.6±7.0 vs. 37.4±2.0, NGF positive cells (cells/MP): 58.4±5.0, 62.4±4.4 vs. 53.4±3.6, all P < 0.05], the increase amplitude at 7 days after injury was more significant than those in the other groups. Conclusions:Taohong Siwu decoction, Xuefu Zhuyu decoction, Tongqiao Huoxue decoction and Buyang Huanwu decoction have curative effect on the nerve regeneration and repair of rats with sTBI at acute stage, but the intensity of the effect is different. Buyang Huanwu decoction and Tongqiao Huoxue decoction have a fast and better effect.