Jang Jae-Won, Lee Jung-Kil, Hur Hyuk, Kim Tae-Wan, Joo Sung-Pil, Piao Min-Sheng
Department of Neurosurgery, Chonnam National University Medical School, Gwangju, Republic of Korea; Department of Neurosurgery, Chonnam National University Research Institute of Medical Sciences, Gwangju, Republic of Korea.
Department of Neurosurgery, Chonnam National University Medical School, Gwangju, Republic of Korea; The Brain Korea 21 Project, Center for Biomedical Human Resources, Chonnam National University, Gwangju, Republic of Korea; Department of Neurosurgery, Chonnam National University Research Institute of Medical Sciences, Gwangju, Republic of Korea.
J Neurol Sci. 2014 Apr 15;339(1-2):75-80. doi: 10.1016/j.jns.2014.01.024. Epub 2014 Jan 24.
Blood-brain barrier (BBB) disruption mediated by proteases plays a pivotal role in neural tissue damage after acute ischemic stroke. In an animal stroke model, the activation of matrix metalloproteinases (MMPs), especially MMP-9, was significantly increased and it showed potential association with blood-brain barrier (BBB) disruption and cerebral edema. Theoretically, it is expected that early blockade of expression and activation of MMP-9 after ischemic stroke provides neuroprotective effects from secondary neural tissue damage. This study was aimed to determine the ability of rutin to influence MMP-9 expression, activity and BBB disruption using a photothrombotic focal ischemic model in rats.
Adult male Sprague-Dawley rats, weighing between 250 and 300 g (aged 8 weeks) received focal cerebral ischemia by photothrombosis using Rose Bengal (RB) and cold light. Injured animals were divided into two groups; one group received 50mg/kg of rutin intraperitoneally, starting 1h after injury and at 12h intervals for 3 days, while animals in the control group received weight-adjusted doses of saline vehicle over the same period. In each group, the expressions and activities of MMP-9 were assessed by Western blot and gelatin zymography at 6, 24, 48, and 72 h after photothrombotic insult. The effects of rutin on BBB disruption and functional outcomes were also determined.
Western blot and zymographic analysis showed up-regulated MMP-9 expression and activity in the ischemic cortex. The expression and activity of MMP-9 were significantly elevated at 6h after photothrombotic insult, which remained up-regulated for at least until 72 h after injury. In the rutin-treated group, MMP-9 expression and activity were significantly attenuated at 6, 24, and 48 h compared to the control group. Relative to the control group, BBB permeability was significantly reduced in the rutin-treated group. The results of the rotarod test revealed that rutin treatment significantly improved functional outcomes.
Rutin treatment starting 1h after injury attenuated BBB disruption during photothrombotic focal ischemia, which was partly, at least, achieved through inhibitory effects on MMP-9 expression and activity. The results of this study suggest that rutin might be useful in clinical trials aimed to improve the outcome of patients suffering from acute ischemic stroke.
蛋白酶介导的血脑屏障（BBB）破坏在急性缺血性中风后的神经组织损伤中起关键作用。在动物中风模型中，基质金属蛋白酶（MMPs），尤其是MMP-9的激活显著增加，且显示出与血脑屏障（BBB）破坏和脑水肿存在潜在关联。理论上，预计在缺血性中风后早期阻断MMP-9的表达和激活可提供神经保护作用，防止继发性神经组织损伤。本研究旨在利用大鼠光血栓性局灶性缺血模型确定芦丁影响MMP-9表达、活性及血脑屏障（BBB）破坏的能力。
体重在250至300克（8周龄）之间的成年雄性Sprague-Dawley大鼠通过使用孟加拉玫瑰红（RB）和冷光进行光血栓形成接受局灶性脑缺血。受伤动物分为两组；一组在受伤后1小时开始腹腔注射50mg/kg芦丁，每隔12小时注射一次，共注射3天，而对照组动物在同一时期接受按体重调整剂量的生理盐水。在每组中，在光血栓形成损伤后6、24、48和72小时通过蛋白质印迹法和明胶酶谱法评估MMP-9的表达和活性。还确定了芦丁对血脑屏障（BBB）破坏和功能结果的影响。
蛋白质印迹法和酶谱分析显示缺血皮层中MMP-9表达和活性上调。光血栓形成损伤后6小时，MMP-9的表达和活性显著升高，至少持续上调至损伤后72小时。与对照组相比，在芦丁治疗组中，MMP-9的表达和活性在6、24和48小时时显著减弱。相对于对照组，芦丁治疗组的血脑屏障（BBB）通透性显著降低。转棒试验结果显示芦丁治疗显著改善了功能结果。
受伤后1小时开始的芦丁治疗减轻了光血栓性局灶性缺血期间的血脑屏障（BBB）破坏，这至少部分是通过对MMP-9表达和活性的抑制作用实现的。本研究结果表明，芦丁可能在旨在改善急性缺血性中风患者预后的临床试验中有用。
