Research on Spatiotemporal Gene Expression Profiles and Repair Mechanisms of Spinal Cord Compression and Hemisection Spinal Cord Injury Mouse Models
10.12300/j.issn.1674-5817.2025.052
- VernacularTitle:脊髓压迫和半横断损伤小鼠模型的时空基因表达谱及修复机制研究
- Author:
Bo XU
1
;
Tairen CHEN
2
;
Qian FANG
1
;
Ji WU
1
Author Information
1. Key Laboratory of Hereditary Development and Mental Neurological Diseases of the Ministry of Education, Bio-X Institute, Shanghai Jiao Tong University, Shanghai 200240, China
2. Pathology Department of Ganzhou People's Hospital, Ganzhou 341000, China
- Publication Type:Journal Article
- Keywords:
Spinal cord injury;
ICR mice;
Mouse model;
Spinal cord compression injury;
Hemisection spinal cord injury;
RNA-Seq;
Neural repair
- From:
Laboratory Animal and Comparative Medicine
2026;46(1):32-45
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the gene expression sequence and molecular mechanisms in the local microenvironment during the subacute to chronic phases (1-28 days) in mouse models of spinal cord compression injury and hemisection spinal cord injury, thereby revealing the molecular characteristics of spinal cord repair and providing a theoretical basis for selecting therapeutic targets for spinal cord injury. MethodsThirty-six 8-9-week-old SPF-grade ICR mice were randomly divided into three groups (n=12 per group): sham-operated control (CTR) group, hemisection spinal cord injury (HSCI) group, and spinal cord compression injury (SCC) group. Mice in the CTR group underwent the same surgical preparation and anesthesia, followed by a dorsal midline incision at the T9-T10 segment. After layer-by-layer dissection and removal of the corresponding lamina, the spinal cord dura mater was fully exposed and kept intact. The cord was exposed to air for 10 minutes (matching the duration of the compression injury group), during which any instrument contact with the cord was avoided. The incision was then irrigated and sutured. The HSCI group underwent a 70% transection of the T9 spinal cord segment using micro-instruments to establish a hemisection spinal cord injury model. The SCC group underwent sustained compression of the T10 spinal cord segment for 10 minutes using a self-made compressor (a 30 g solid small iron bar) to establish a spinal cord compression injury model. Motor function recovery was assessed using the modified Basso-Beattie-Bresnahan (BBB) score on postoperative days 1, 3, 7, 14, 21, and 28. On days 7 and 14 post-operation, mice were anesthetized, and the injured spinal cord segments were harvested. The evolution of specific molecular networks in the spinal cord injury mouse models was analyzed via RNA sequencing (RNA-Seq) and enrichment analysis, and the expression of key genes was verified using real time fluorogenic quantitative PCR. ResultsBBB scores indicated that motor function recovery in the SCC group was significantly better than that in the HSCI group, with BBB scores showing a continuously increasing trend and remaining higher than those in the HSCI group over the 4-week period (P <0.001). Gene ontology （GO)and Kyoto Encyclopedia of Genes and Genomes （KEGG） enrichment analyses based on RNA-Seq differentially expressed genes revealed that, compared to the CTR group, genes related to the extracellular matrix were significantly up-regulated (P<0.05), while genes related to axon guidance were significantly down-regulated (P <0.05) in the SCC group on day 7 post-operation. On day 21, genes involved in immune regulation and the retinol signaling pathway were significantly activated in the SCC group (P<0.05). In contrast, in the HSCI group, genes associated with inflammation and immune response were significantly up-regulated (P<0.001), while genes related to neuronal differentiation and synapse formation were significantly down-regulated (P <0.001) on day 7. On day 21, genes related to cell-matrix junctions and N-methyl-D-aspartate receptors were significantly up-regulated (P<0.001) in the HSCI group. Furthermore, compared to the SCC group, the HSCI group exhibited different pathway enrichment characteristics in GO and KEGG analyses on days 7 and 21 post-injury. On day 7, genes involved in the NOD-like receptor signaling pathway and the complement and coagulation cascades were significantly up-regulated in the HSCI group (P<0.001). On day 21, genes related to the extracellular matrix-receptor interaction and the neuroactive ligand-receptor interaction pathways were significantly activated (P<0.001). Finally, real time fluorogenic quantitative PCR validation results were highly consistent with the RNA-Seq results, further confirming the differential expression trends of key genes between the SCC and HSCI groups. ConclusionThe SCC and HSCI injury models may drive distinct repair pathways: the preservation of some axons in the SCC model predisposes it toward tissue repair, whereas the HSCI model requires the coordination of more complex molecular networks to achieve a new equilibrium. This finding further deepens the understanding of the heterogeneous regulatory mechanisms underlying spinal cord injury.
