BACKGROUND Traumatic Spinal Cord Injury (SCI) is a severe condition usually accompanied by an inflammatory process that gives rise to uncontrolled local apoptosis and a subsequent unfavorable prognosis. One reason for this unfavorable outcome could be the activation of the NLRP3 inflammasome. OBJECTIVE MCC950 is a specific inhibitor of NLRP3 that further inhibits the formation of the NLRP3 inflammasome. The purpose of this study was to determine whether the NLRP3 inflammasome was associated with the severity of local apoptosis and whether MCC950 could prevent neuronal apoptosis following SCI. METHODS In this study, primary cortical neurons were cultured in vitro. With or without pretreatment/ posttreatment with MCC950, neurons were subjected to Oxygen-Glucose Deprivation (OGD) for 2 h and then reperfusion for 20 h. Immunofluorescence was used to determine the expression of NLRP3, ASC, and cleaved caspase-1 in neurons. In vivo, SCI model mice were established with a 5 g weight-drop method. MCC950 was intraperitoneally injected at 0, 2, 4, 6, 8, 10, and 12 days after SCI. Basso Mouse Scale (BMS) scores and footprint assays were used to assess motor function. Paw withdrawal threshold and tail-flick latency were used to assess somatosensory function. H&E, Nissl, and TUNEL staining were used to measure histological changes and apoptosis at 3 days after SCI, and scar formation was observed by Masson staining and GFAP immunohistochemical analysis at 28 days after SCI. RESULTS Immunofluorescence analysis confirmed that MCC950 inhibited OGD-induced activation of the NLRP3 inflammasome in neurons. Behavioral tests, Masson staining, and GFAP immunohistochemical analysis showed that MCC950-treated mice had improved neuronal functional recovery and reduced scar formation at 28 days after SCI. H&E, Nissl, and TUNEL staining confirmed that there were more living neurons and fewer apoptotic neurons in MCC950-treated mice than control mice at 3 days after SCI. CONCLUSION These results reveal that MCC950 exerts neuroprotective effects by reducing neuronal apoptosis, preserving the survival of the remaining neurons, attenuating the severity of the damage, and promoting the recovery of motor function after SCI.

中文翻译：

---

MCC950 减少小鼠脊髓损伤中的神经元凋亡。

背景技术创伤性脊髓损伤（SCI）是一种严重的疾病，通常伴有炎症过程，导致不受控制的局部细胞凋亡和随后的不良预后。这种不利结果的一个原因可能是 NLRP3 炎性体的激活。目标 MCC950 是 NLRP3 的特异性抑制剂，可进一步抑制 NLRP3 炎性体的形成。本研究的目的是确定 NLRP3 炎性体是否与局部细胞凋亡的严重程度相关，以及 MCC950 是否可以预防 SCI 后的神经元细胞凋亡。方法在本研究中，原代皮层神经元在体外培养。在有或没有用 MCC950 预处理/后处理的情况下，对神经元进行氧 - 葡萄糖剥夺 (OGD) 2 小时，然后再灌注 20 小时。免疫荧光用于确定神经元中 NLRP3、ASC 和 cleaved caspase-1 的表达。在体内，采用 5 g 减重法建立 SCI 模型小鼠。在 SCI 后 0、2、4、6、8、10 和 12 天腹膜内注射 MCC950。Basso Mouse Scale (BMS) 评分和足迹测定用于评估运动功能。爪缩回阈值和甩尾潜伏期用于评估体感功能。H&E、Nissl和TUNEL染色用于测量SCI后3天的组织学变化和细胞凋亡，并在SCI后28天通过Masson染色和GFAP免疫组织化学分析观察瘢痕形成。结果免疫荧光分析证实MCC950抑制OGD诱导的神经元NLRP3炎性体的激活。行为测试，Masson 染色，和 GFAP 免疫组织化学分析表明，MCC950 治疗的小鼠在 SCI 后 28 天改善了神经元功能恢复并减少了瘢痕形成。H&E、Nissl 和 TUNEL 染色证实，在 SCI 后 3 天，MCC950 处理的小鼠比对照小鼠有更多的活神经元和更少的凋亡神经元。结论 这些结果表明，MCC950 通过减少神经元凋亡、保留剩余神经元的存活、减轻损伤的严重程度和促进 SCI 后运动功能的恢复来发挥神经保护作用。和 TUNEL 染色证实，在 SCI 后 3 天，MCC950 处理的小鼠比对照小鼠有更多的活神经元和更少的凋亡神经元。结论 这些结果表明，MCC950 通过减少神经元凋亡、保留剩余神经元的存活、减轻损伤的严重程度和促进 SCI 后运动功能的恢复来发挥神经保护作用。和 TUNEL 染色证实，在 SCI 后 3 天，MCC950 处理的小鼠比对照小鼠有更多的活神经元和更少的凋亡神经元。结论 这些结果表明，MCC950 通过减少神经元凋亡、保留剩余神经元的存活、减轻损伤的严重程度和促进 SCI 后运动功能的恢复来发挥神经保护作用。