Abstract: Objective　To explore the protective effect of tetramethylpyrazine (TMP) on vascular endothelium and nerves in rats with spinal cord injury (SCI), and to analyze its mechanism of action in the treatment of SCI based on the miR-497-5p/EGFL7 axis.Methods　A total of 78 healthy male SD rats were randomly grouped into 13 groups, with 6 rats in each group. The SCI rat model was constructed by the modified Allen method, and then TMP intervention was continuously given for 2 weeks. The expression levels of miR-497-5p and epidermal growth-like protein 7 (EGFL7) were detected by RT qPCR and Western blot. Meanwhile, Basso, Beattie and Bresnahan (BBB) scoring, footprint analysis,  HE staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, enzyme linked immunosorbent assay (ELISA), dual-luciferase reporter assay and in vivo gene regulation experiments were employed. A comprehensive evaluation was conducted on indicators such as motor function, spinal cord tissue injury, apoptosis, inflammatory response and angiogenesis in rats.Results After SCI,the expression of miR-497-5p in the spinal cord tissue of rats was significantly increased, and the expression of EGFL7 was significantly decreased. At the same time, it was accompanied by typical manifestations such as motor dysfunction, tissue structure destruction, increased apoptosis and elevated levels of inflammatory factors. After TMP intervention, the above-mentioned abnormal changes were significantly improved. Specifically, the expression of miR-497-5p was down-regulated, the expression of EGFL7 was up-regulated, the BBB score and footprint analysis indicators were improved, the degree of pathological damage and apoptosis was reduced, and the expression of platelet endothelial cell adhesion molecule-1 (CD31) was increased. The levels of tumor necrosis factor -α (TNF-α), transforming growth factor-β1 (TGF-β1), and interleukin-1 β (IL-1β) decreased.Conclusion　TMP improves the local microenvironment following SCI by regulating the miR-497-5p/EGFL7 axis, thereby promoting angiogenesis and neural repair. Downregulation of miR-497-5p or upregulation of EGFL7 enhances its protective effects, whereas their opposite regulation attenuates these effects.

Key words: tetramethylpyrazine, miR-497-5p, EGFL7, angiogenesis, spinal cord injury, neural regeneration

摘要： 目的　探讨川芎嗪(TMP)对脊髓损伤(SCI)大鼠血管内皮和神经的保护作用,并分析其基于miR-497-5p/ EGFL7轴治疗SCI的作用机制。方法　将78只健康雄性SD大鼠随机分为 13 组,每组 6 只,采用改良Allen法构 建SCI大鼠模型,后连续给予TMP干预2周。通过RT-qPCR与Western blot检测miR-497-5p及表皮生长因子样蛋 白7(EGFL7)的表达水平,同时运用BBB评分、足迹分析、HE染色、TUNEL染色、酶联免疫吸附测定(ELISA)、双荧 光素酶报告实验及体内基因调控实验,对大鼠运动功能、脊髓组织损伤、细胞凋亡、炎性反应及血管生成等指标进 行全面评价。结果　SCI后大鼠脊髓组织中miR-497-5p表达显著升高,EGFL7表达显著降低,同时伴随运动功能 障碍、组织结构破坏、细胞凋亡增多及炎性因子水平升高的典型表现;经TMP干预后,上述异常改变均得到明显改 善,具体表现为miR-497-5p表达下调、EGFL7表达上调,BBB评分及足迹分析指标改善,病理损伤及细胞凋亡程度 减轻,血小板内皮细胞黏附分子-1(CD31)表达升高,肿瘤坏死因子α(TNF-α)、转化生长因子β1(TGF-β1)和白细 胞介素1β(IL-1β )水平下降。结论　TMP通过调控miR-497-5p/EGFL7轴改善SCI后局部微环境,促进血管生成 与神经修复;下调miR-497-5p或上调EGFL7可增强其保护作用,反之则削弱。

关键词: 川芎嗪, miR-497-5p, 表皮生长因子样蛋白7, 血管生成, 脊髓损伤, 神经再生