Department of Orthopaedics, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China.
Department of Orthopaedics, Xi'an International Medical Center Hospital, Xi'an, Shaanxi 710100, China.
Oxid Med Cell Longev. 2022 Feb 21;2022:6041612. doi: 10.1155/2022/6041612. eCollection 2022.
Aberrantly expressed microRNAs (miRNAs) after spinal cord injury (SCI) participate in diverse biological pathways and processes, including apoptosis, inflammation, oxidative stress responses, peroxidation, and ferroptosis. This study was aimed at exploring the mechanisms underlying miRNA-mediated ferroptosis in an SCI rat model. In the present study, a T10 weight-dropping SCI model was established and miRNA profiling was used to detect miRNA expression profiles post-SCI. Basso-Beattie-Bresnahan scores and inclined plane test, hematoxylin and eosin (HE) and Nissl staining, immunohistochemistry and immunofluorescence, western blotting, cell viability, and Annexin V/7-aminoactinomycin D (7-AAD) assays were used to evaluate locomotor activity, histological changes in the injured spinal cords, neuronal ferroptosis, ferroptosis suppressor protein 1 (FSP1) expression, and cell death, respectively. It was observed that many miRNAs were differentially expressed after SCI, and miR-672-3p, which increased significantly, was selected after cross-referencing with predicted target miRNAs. The luciferase reporter assay demonstrated that miR-672-3p downregulated FSP1, a glutathione-independent ferroptosis suppressor, by binding to its 3' untranslated region. Oxygen and glucose deprivation- (OGD-) treated PC12 and AGE1.HN cells were treated with miR-672-3p mimics or inhibitors . The effect of miR-672-3p mimics or inhibitor on OGD-PC12/AGE1.HN ferroptosis was evaluated by flow cytometry, immunohistochemistry, immunofluorescence, and western blotting. The miR-672-3p mimics promoted ferroptosis after SCI, whereas the miR-672-3p inhibitor inhibited this process. Rats with SCI treated with miR-672-3p mimics or inhibitor showed similar results . Furthermore, the ferroptosis-related changes caused by SCI or miR-672-3p were reversed by overexpression of FSP1 lentivirus and . These results indicated that sh-miR-672-3p exerted a neural restoration effect and by inhibiting ferroptosis via the FSP1 pathway.
脊髓损伤 (SCI) 后异常表达的 microRNAs (miRNAs) 参与多种生物学途径和过程，包括细胞凋亡、炎症、氧化应激反应、过氧化和铁死亡。本研究旨在探讨 miRNA 介导的铁死亡在 SCI 大鼠模型中的机制。本研究建立了 T10 重物坠落 SCI 模型，并使用 miRNA 谱分析检测 SCI 后 miRNA 表达谱。Basso-Beattie-Bresnahan 评分和斜面试验、苏木精和伊红 (HE) 和尼氏染色、免疫组织化学和免疫荧光、western blot、细胞活力和 Annexin V/7-氨基放线菌素 D (7-AAD) 测定分别用于评估运动活动、损伤脊髓的组织学变化、神经元铁死亡、铁死亡抑制蛋白 1 (FSP1) 表达和细胞死亡。结果发现，SCI 后许多 miRNA 表达差异，经与预测靶 miRNA 交叉参考后选择 miR-672-3p 表达明显增加。荧光素酶报告基因检测表明，miR-672-3p 通过与其 3'UTR 结合下调 FSP1，FSP1 是一种谷胱甘肽非依赖性铁死亡抑制剂。用 miR-672-3p 模拟物或抑制剂处理氧和葡萄糖剥夺 (OGD-) 处理的 PC12 和 AGE1.HN 细胞。通过流式细胞术、免疫组织化学、免疫荧光和 western blot 评估 miR-672-3p 模拟物或抑制剂对 OGD-PC12/AGE1.HN 铁死亡的影响。SCI 后 miR-672-3p 模拟物促进铁死亡，而 miR-672-3p 抑制剂抑制此过程。用 miR-672-3p 模拟物或抑制剂处理 SCI 大鼠的结果相似。此外，SCI 或 miR-672-3p 引起的铁死亡相关变化可通过 FSP1 慢病毒过表达逆转。这些结果表明，sh-miR-672-3p 通过 FSP1 途径抑制铁死亡发挥神经修复作用。
