Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India.
Department of Pharmacology, All India Institute of Medical Sciences, New Delhi, India.
Neurochem Int. 2019 Jun;126:96-108. doi: 10.1016/j.neuint.2019.03.010. Epub 2019 Mar 14.
Post stroke recanalization has been associated with increased risk of oxidative stress. Stimulating endogenous antioxidant pathway by activation of nuclear factor erythroid-2-related factor-2 (Nrf2) plays a key role in neuronal defense against inflammation and oxidative stress in penumbra. Here, we explored whether monomethyl fumarate (MMF) could produce neuro-protection after ischemia/reperfusion (I/R) injury via Nrf2/HO1 activation. In male SD rats, middle cerebral artery was occluded for 90 min and confirmed using Laser Doppler flowmeter. MMF (10, 20 and 40 mg/kg) was administered in two divided doses at 30 min post ischemia and 5-10 min after reperfusion. After 24 h, effect on neurobehavioral parameters, infarct damage by TTC staining and MRI, oxidative stress and inflammatory cytokines were assessed. Expression studies of nuclear Nrf2 and cytoplasmic HO1 were performed in peri-infarct cortex and striatum; followed by dual immunofluorescence study to check the specific cell type. I/R induced neurobehavioral deficits and infarct damage were significantly (p < 0.05) attenuated by MMF (20 and 40 mg/kg). MMF, 20 mg/kg, significantly normalized I/R induced altered redox status and increased levels of TNF-α, IL-1β in the ipsilateral cortex. MRI data showed significantly reduced infarct in cortex but not in striatum after MMF treatment. Expression of nuclear Nrf2 and cytoplasmic HO1 were significantly (p < 0.05) increased in peri-infarct cortex after treatment with MMF. Additionally, dual immunofluorescence showed increased Nrf2 expression in neurons and HO1 expression in neurons as well as astrocytes in peri-infarct cortex after MMF treatment. Our results show the neuro-protective potential of MMF probably by restricting the progression of damage from striatum to cortex through activation of Nrf2/HO1 pathway in peri-infarct cortex.
中风后再通与氧化应激风险增加有关。通过激活核因子红细胞 2 相关因子 2(Nrf2)刺激内源性抗氧化途径,在半影区中对神经元起到抵抗炎症和氧化应激的关键作用。在这里,我们探讨了富马酸单甲酯(MMF)是否可以通过 Nrf2/HO1 激活来产生缺血/再灌注(I/R)损伤后的神经保护作用。在雄性 SD 大鼠中,通过激光多普勒血流计确认大脑中动脉闭塞 90min。缺血后 30min 和再灌注后 5-10min 分两次给予 MMF(10、20 和 40mg/kg)。24h 后,评估神经行为学参数、TTC 染色和 MRI 评估梗死损伤、氧化应激和炎性细胞因子。在梗死周围皮质和纹状体中进行核 Nrf2 和胞质 HO1 的表达研究;随后进行双免疫荧光研究以检查特定细胞类型。I/R 诱导的神经行为缺陷和梗死损伤明显(p<0.05)被 MMF(20 和 40mg/kg)减轻。MMF(20mg/kg)显著使 I/R 诱导的氧化还原状态改变和同侧皮质中 TNF-α、IL-1β水平升高恢复正常。MRI 数据显示 MMF 治疗后皮质梗死明显减少,但纹状体无变化。治疗后 MMF 使梗死周围皮质中核 Nrf2 和胞质 HO1 的表达明显增加(p<0.05)。此外,双免疫荧光显示 MMF 治疗后梗死周围皮质中 Nrf2 表达增加,神经元和星形胶质细胞中 HO1 表达增加。我们的研究结果表明,MMF 的神经保护作用可能是通过激活梗死周围皮质中的 Nrf2/HO1 途径来限制损伤从纹状体向皮质的进展。