中国神经再生研究(英文版) ›› 2023, Vol. 18 ›› Issue (10): 2268-2277.doi: 10.4103/1673-5374.369125

• 原著:脑损伤修复保护与再生 • 上一篇    下一篇

创伤性脑损伤模型精确分类:从宏观血流到微观线粒体的变化

  

  • 出版日期:2023-10-15 发布日期:2023-03-29
  • 基金资助:
    国家科技创新2030资助项目;国家自然科学基金;陕西省自然科学基金;陕西省重点研发计划

Characteristics of traumatic brain injury models: from macroscopic blood flow changes to microscopic mitochondrial changes

Ding-Ding Yang1, #, Xiang-Dong Wan1, 2, #, An-Di Chen1, #, Zi-Qian Yan1, 2, Yi-Fan Lu1, 3, Jun-Chen Liu1, Ya-Zhou Wang1, Jing Wang4, Yan Zhao5, *, Sheng-Xi Wu1, *, Guo-Hong Cai1, 4, *#br#   

  1. 1Department of Neurobiology, School of Basic Medicine, Forth Military Medical University, Xi’an, Shaanxi Province, China; 2Hebei Medical University, Shijiazhuang, Hebei Province, China; 3College of Life Sciences & Research Center for Resource Peptide Drugs, Yan’an University, Yan’an, Shaanxi Province, China; 4Department of Nuclear Medicine, First Affiliated Hospital of Forth Military Medical University, Xi’an, Shaanxi Province, China; 5Department of Gastroenterology, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi Province, China
  • Online:2023-10-15 Published:2023-03-29
  • Contact: Guo-Hong Cai, PhD, guohong_neuron@163.com; Sheng-Xi Wu, PhD, shengxi@fmmu.edu.cn; Yan Zhao, MD, yanzhao211@163.com.
  • Supported by:
    This work was supported by grants from the National Science and Technology Innovation 2030 Grant of China, No. 2021ZD0201005 (to SXW); Natural Science Foundation of China, Nos. 81900489 (to YZ), 82101294 (to GHC), 81730035 (to SXW), Natural Science Foundation of Shaanxi Province, No. 2022JM-456 (to YZ); Shaanxi Provincial Key Research and Development Program, Nos. 2022SF-011 (to GHC), 2022ZDLSF01-02 (to YZW).

摘要:

目前,控制性脑皮质撞击(CCI)是一种被广泛接受的建立创伤性脑损伤(TBI)动物模型的方法。中度和重度脑损伤的推荐撞击深度分别为1和>2mm;然而,这两种造模方法的效果和基本机制还没有得到证实。实验旨在了解3,4,5 m/s的损伤速度下,1和2 mm的不同损伤参数下的脑血流变化、皮质损伤程度以及运动功能的差异,以及在急性期(7天)和慢性期(30天)的功能变化和线粒体损伤。结果显示,1毫米组受伤区域的脑血流明显增加,脑组织肿胀和隆起,血管通透性增加,并出现大规模渗出。2 mm组的主要病理变化是脑血流减少,脑组织缺失,伤后24h内存在脑血管痉挛闭塞。2mm组小鼠在伤后7d出现了明显的运动和认知功能障碍。30d后,2mm组小鼠的运动功能明显恢复,而认知功能障碍仍然存在。转录组测序的结果显示,与1 mm组相比,2 mm组有更严重的铁死亡。透射电子显微镜观察了线粒体的形态学变化显示,伤后7天两组的线粒体收缩,空泡变大;伤后30天,1 mm组的线粒体变大,而2 mm组的空泡仍然扩大。进一步分析不同组别中线粒体亚群的比例发现模型小鼠在不同时期的线粒体组成模式不同,说明不同TBI损伤程度的差异可能反映在线粒体的微观变化上。总之,实验结果为TBI的准确分类和治疗提供了数据支撑,并为进一步建立标准动物模型提供了可靠的数据和评估方法。

https://orcid.org/0000-0001-7511-7420 (Guo-Hong Cai); https://orcid.org/0000-0002-3210-9567 (Sheng-Xi Wu); https://orcid.org/0000-0002-0638-4741 (Yan Zhao)

Abstract: Controlled cortical impingement is a widely accepted method to induce traumatic brain injury to establish a traumatic brain injury animal model. A strike depth of 1 mm at a certain speed is recommended for a moderate brain injury and a depth of > 2 mm is used to induce severe brain injury. However, the different effects and underlying mechanisms of these two model types have not been proven. This study investigated the changes in cerebral blood flow, differences in the degree of cortical damage, and differences in motor function under different injury parameters of 1 and 2 mm at injury speeds of 3, 4, and 5 m/s. We also explored the functional changes and mitochondrial damage between the 1 and 2 mm groups in the acute (7 days) and chronic phases (30 days). The results showed that the cerebral blood flow in the injured area of the 1 mm group was significantly increased, and swelling and bulging of brain tissue, increased vascular permeability, and large-scale exudation occurred. In the 2 mm group, the main pathological changes were decreased cerebral blood flow, brain tissue loss, and cerebral vasospasm occlusion in the injured area. Substantial motor and cognitive impairments were found on day 7 after injury in the 2 mm group; at 30 days after injury, the motor function of the 2 mm group mice recovered significantly while cognitive impairment persisted. Transcriptome sequencing showed that compared with the 1 mm group, the 2 mm group expressed more ferroptosis-related genes. Morphological changes of mitochondria in the two groups on days 7 and 30 using transmission electron microscopy revealed that on day 7, the mitochondria in both groups shrank and the vacuoles became larger; on day 30, the mitochondria in the 1 mm group became larger, and the vacuoles in the 2 mm group remained enlarged. By analyzing the proportion of mitochondrial subgroups in different groups, we found that the model mice had different patterns of mitochondrial composition at different time periods, suggesting that the difference in the degree of damage among traumatic brain injury groups may reflect the mitochondrial changes. Taken together, differences in mitochondrial morphology and function between the 1 and 2 mm groups provide a new direction for the accurate classification of traumatic brain injury. Our results provide reliable data support and evaluation methods for promoting the establishment of standard mouse controlled cortical impingement model guidelines.

Key words: cerebral blood flow, cognitive impairments, controlled cortical impingement, ferroptosis, mitochondrial dysfunction, motor impairments, mouse model, traumatic brain injury