Mirshekari Jahangiri Hamzeh, Moradi Alireza, Nazarinia Donya, Aboutaleb Nahid
Department of Physiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran.
Arch Acad Emerg Med. 2024 Sep 17;13(1):e8. doi: 10.22037/aaem.v13i1.2456. eCollection 2025.
Ischemic stroke (IS) is one of the three main fatal disorders and is a major health challenge. 4-methylumbelliferone (4-MU) is one of the coumarin derivatives (7-hydroxy-4-methylcoumarin) with antioxidant and anti-inflammatory impact. This study was conducted to elucidate the neuroprotective effects and anti-inflammatory impact of 4-MU in a rodent model of IS.
The IS model was induced by middle cerebral artery occlusion (MCAO) for 1 hour and reperfusion was established for 24 hours. 44 Male Wistar rats were divided into four groups: 1) Sham, 2) MCAO, 3) MCAO + Vehicle, and 4) MCAO + 4-MU (25 mg/kg). Evaluation of neurological deficit was performed using Garcia's score. 2,3,5-triphenoyl-2H-tetrazolium chloride (TTC) staining was employed to measure infarct size. Nissl staining was applied to determine neuronal loss. Moreover, western blotting was utilized to detect the expression of the proteins relevant to the TLR4/NF-κB/NLRP3 axis (p-NF-κB p65, TLR4, NLRP3, IL-1β, IL-10, IL-18, ASC, and Caspase-1).
It was observed that MCAO caused neurological deficit (P<0.0001), infarct (P<0.0001), and neuronal loss (P<0.002); up-regulated NLRP3 (P<0.0001), TLR4 (P<0.0001), p-NF-κB p65 (P<0.0005), IL-1β (P<0.0014), IL-18 (P<0.0001), ASC (P<0.0027), and Caspase-1 (P<0.0052); and reduced IL-10 concentrations (P<0.0024). Administration of 4-MU (25 mg/kg) quickly after reperfusion reduced neurological deficit (P<0.0001), infarct size (P<0.0001), neuronal loss (P<0.0058), and down-regulated NLRP3 (P<0.0257), TLR4 (P<0.0001), p-NF-κB p65 (P<0.0075), IL-1β (P<0.0106), IL-18 (P<0.0005), ASC (P<0.0072), and Caspase-1 (P<0.0315), and increased IL-10 concentrations (P<0.0215).
These results indicate that 4-MU can attenuate injury after MCAO by suppressing the TLR4/NF-κB/NLRP3 axis. Our findings show that 4-MU can be considered a novel therapeutic compound to cure IS.
缺血性中风（IS）是三大主要致命疾病之一，是一项重大的健康挑战。4-甲基伞形酮（4-MU）是香豆素衍生物（7-羟基-4-甲基香豆素）之一，具有抗氧化和抗炎作用。本研究旨在阐明4-MU在缺血性中风啮齿动物模型中的神经保护作用和抗炎作用。
通过大脑中动脉闭塞（MCAO）1小时诱导缺血性中风模型，并建立24小时的再灌注。44只雄性Wistar大鼠分为四组：1）假手术组，2）MCAO组，3）MCAO+溶剂组，4）MCAO+4-MU（25mg/kg）组。使用加西亚评分评估神经功能缺损。采用2,3,5-三苯基氯化四氮唑（TTC）染色测量梗死面积。应用尼氏染色确定神经元损失。此外，利用蛋白质印迹法检测与TLR4/NF-κB/NLRP3轴相关的蛋白质（p-NF-κB p65、TLR4、NLRP3、IL-1β、IL-10、IL-18、ASC和Caspase-1）的表达。
观察到MCAO导致神经功能缺损（P<0.0001）、梗死（P<0.0001）和神经元损失（P<0.002）；上调NLRP3（P<0.0001）、TLR4（P<0.0001）、p-NF-κB p65（P<0.0005）、IL-1β（P<0.0014）、IL-18（P<0.0001）、ASC（P<0.0027）和Caspase-1（P<0.0052）；并降低IL-10浓度（P<0.0024）。再灌注后迅速给予4-MU（25mg/kg）可减轻神经功能缺损（P<0.0001）、梗死面积（P<0.0001）、神经元损失（P<0.0058），并下调NLRP3（P<0.0257）、TLR4（P<0.0001）、p-NF-κB p65（P<0.0075）、IL-1β（P<0.0106）、IL-18（P<0.0005）、ASC（P<0.0072）和Caspase-1（P<0.0315），并增加IL-10浓度（P<0.0215）。
这些结果表明，4-MU可通过抑制TLR4/NF-κB/NLRP3轴减轻MCAO后的损伤。我们的研究结果表明，4-MU可被视为一种治疗缺血性中风的新型治疗化合物。
