Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
Department of Orthopaedics, The Second People's Hospital of Hefei, Hefei, Anhui, China.
Inflammopharmacology. 2024 Feb;32(1):523-536. doi: 10.1007/s10787-023-01311-z. Epub 2023 Aug 14.
Neuroinflammation plays an important role in spinal cord injury (SCI), and an increasing number of studies have focused on the role of astrocytes in neuroinflammation. Pyroptosis is an inflammation-related form of programmed cell death, and neuroinflammation induced by astrocytes in the form of pyroptosis has been widely reported in many central nervous system diseases. Recent studies have found that erythropoietin has significant anti-inflammatory and neuroprotective effects in SCI; however, it has not been reported whether erythropoietin can reduce neuroinflammation by inhibiting neural cell pyroptosis in SCI.
A GEO dataset (GSE153720) was used to analyse the expression of pyroptosis-related genes in sham astrocytes and astrocytes 7 days, 1 month and 3 months after SCI. TargetScan and miRDB databases were used to predict the miRNA that could bind to the 3'UTR of rat Gsdmd. Primary rat spinal astrocytes were used for in vitro experiments, and the modified version of Allen's method was used to establish the rat SCI model. Western blotting, quantitative real-time polymerase chain reaction, flow cytometry, immunofluorescence, lactate dehydrogenase release assay and propidium iodide staining were used to detect the pyroptosis phenotype. A dual luciferase reporter gene assay was used to verify that miR-325-3p can bind to the 3'UTR of Gsdmd.
We found that pyroptosis-related genes mediated by the canonical NLRP3 inflammasome were highly expressed in astrocytes in an SCI animal model by bioinformatic analysis. We also observed that erythropoietin could reduce astrocyte pyroptosis in vivo and in vitro. In addition, we predicted miRNAs that regulate Gsdmd, the pyroptosis executor, and verified that erythropoietin inhibits astrocyte pyroptosis in SCI through the miR-325-3p/Gsdmd axis.
We demonstrated that erythropoietin can inhibit astrocyte pyroptosis through the miR-325-3p/Gsdmd axis. This study is expected to provide a new mechanism for erythropoietin in the treatment of SCI and a more reliable theoretical basis for clinical research.
神经炎症在脊髓损伤（SCI）中起着重要作用，越来越多的研究关注星形胶质细胞在神经炎症中的作用。细胞焦亡是一种与炎症相关的程序性细胞死亡形式，星形胶质细胞以细胞焦亡的形式引起的神经炎症已在许多中枢神经系统疾病中广泛报道。最近的研究发现，促红细胞生成素在 SCI 中有显著的抗炎和神经保护作用；然而，尚未有报道称促红细胞生成素是否可以通过抑制 SCI 中神经细胞焦亡来减轻神经炎症。
使用 GEO 数据集（GSE153720）分析假手术星形胶质细胞和 SCI 后 7 天、1 个月和 3 个月的星形胶质细胞中与细胞焦亡相关的基因表达。使用 TargetScan 和 miRDB 数据库预测可以与大鼠 Gsdmd 3'UTR 结合的 miRNA。原代大鼠脊髓星形胶质细胞用于体外实验，采用改良版 Allen 法建立大鼠 SCI 模型。使用 Western blot、实时定量聚合酶链反应、流式细胞术、免疫荧光、乳酸脱氢酶释放测定和碘化丙啶染色检测焦亡表型。双荧光素酶报告基因实验验证 miR-325-3p 可以与 Gsdmd 的 3'UTR 结合。
通过生物信息学分析，我们发现经典 NLRP3 炎性小体介导的与细胞焦亡相关的基因在 SCI 动物模型中星形胶质细胞中高表达。我们还观察到促红细胞生成素可以减少体内和体外星形胶质细胞的细胞焦亡。此外，我们预测了调节 Gsdmd 的 miRNAs，即细胞焦亡执行者，并通过促红细胞生成素抑制 SCI 中星形胶质细胞焦亡的 miR-325-3p/Gsdmd 轴证实了这一点。
我们证明促红细胞生成素可以通过 miR-325-3p/Gsdmd 轴抑制星形胶质细胞焦亡。本研究为促红细胞生成素在 SCI 治疗中的作用提供了新的机制，并为临床研究提供了更可靠的理论依据。
