Electrophysiology Lab, School of Biomedical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, India.
Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India.
Naunyn Schmiedebergs Arch Pharmacol. 2019 Oct;392(10):1293-1309. doi: 10.1007/s00210-019-01670-x. Epub 2019 Jun 12.
The ischemic cascade is initiated in the hypoperfused region of the brain that leads to neuronal cell death. Identification of multi-target inhibitor against prominent molecular mediators of ischemic cascade might be a suitable strategy to combat cerebral ischemic stroke. The present study is designed to evaluate the neuroprotective efficacy of chlorogenic acid (CGA) in the global cerebral ischemic rat model. The effective dose of CGA was evaluated on the basis of reduction in cerebral infarction area percentage, Evans blue extravasation, and restoration of brain water content. The expression of tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), and caspase-3 was evaluated by immunohistochemistry and morphological and cellular alterations in the cortex were observed by brain histology. The level of glutamate, calcium, and nitrate in different regions of the brain, as well as cerebrospinal fluid (CSF), was evaluated. The level of calcium and nitrate was compared with ifenprodil-an antagonist of N-methyl-D-aspartate receptor (NMDAR) and 7-nitroindazole-an inhibitor of neuronal nitric oxide synthase (nNOS) respectively. Further, molecular docking was performed to compare the inhibition potential of CGA against NMDAR and nNOS with their inhibitors. Dose optimization results revealed that intranasal administration of CGA (10 mg/kg b.w.) significantly reduced the cerebral infarction area, Evans blue extravasation and restored the brain water content compared with ischemia group. It also significantly reduced the calcium, nitrate, and glutamate levels compared with ischemia group in the cortex, hippocampus cerebellum, and CSF. Immunohistochemical analysis revealed that CGA significantly reduced the expression of TNF-α, iNOS, and caspase-3 as compared with the ischemia group. In molecular docking study, CGA displayed similar binding interaction as that of Ifenprodil and 7-nitroindazole with NMDAR and nNOS respectively. The current findings suggest that the treatment with CGA confers neuroprotection in global ischemic insult by inhibiting and downregulating the different molecular markers of cerebral ischemia.
缺血级联反应始于脑灌注不足的区域，导致神经元细胞死亡。针对缺血级联反应中主要分子介质的多靶点抑制剂的鉴定可能是对抗脑缺血性中风的一种合适策略。本研究旨在评估绿原酸（CGA）在全脑缺血大鼠模型中的神经保护作用。根据脑梗死面积百分比、伊文思蓝渗出和脑水含量的恢复情况，评估 CGA 的有效剂量。通过免疫组织化学评估肿瘤坏死因子-α（TNF-α）、诱导型一氧化氮合酶（iNOS）和半胱天冬酶-3的表达，并通过脑组织学观察皮质的形态和细胞改变。评估不同脑区及脑脊液（CSF）中谷氨酸、钙和硝酸盐的水平，并与 N-甲基-D-天冬氨酸受体（NMDAR）拮抗剂ifenprodil 和神经元型一氧化氮合酶（nNOS）抑制剂 7-硝基吲唑进行比较。此外，还进行了分子对接，以比较 CGA 对 NMDAR 和 nNOS 的抑制潜力及其抑制剂。剂量优化结果表明，与缺血组相比，鼻内给予 CGA（10mg/kg b.w.）可显著减少脑梗死面积、伊文思蓝渗出，并恢复脑水含量。与缺血组相比，CGA 还可显著降低皮质、海马、小脑和 CSF 中的钙、硝酸盐和谷氨酸水平。免疫组织化学分析显示，与缺血组相比，CGA 可显著降低 TNF-α、iNOS 和半胱天冬酶-3的表达。在分子对接研究中，CGA 与 Ifenprodil 和 7-硝基吲唑分别与 NMDAR 和 nNOS 显示出相似的结合相互作用。目前的研究结果表明，CGA 通过抑制和下调脑缺血的不同分子标志物，对全脑缺血损伤具有神经保护作用。
