Department of Operating Room, Children's Hospital, Chongqing Medical University, Chongqing, China ; Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital, Chongqing Medical University, Chongqing, China.
Hematopoietic Stem Cell Transplantation and Gene Therapy Center, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, China ; State Key Laboratory of Trauma, Burn and Combined Injury, Daping Hospital, Third Military Medical University, Chongqing, China ; Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, China.
PLoS One. 2013 Dec 9;8(12):e82729. doi: 10.1371/journal.pone.0082729. eCollection 2013.
Ischemic stroke induces microglial activation and release of proinflammatory cytokines, contributing to the expansion of brain injury and poor clinical outcome. Propofol has been shown to ameliorate neuronal injury in a number of experimental studies, but the precise mechanisms involved in its neuroprotective effects remain unclear. We tested the hypothesis that propofol confers neuroprotection against focal ischemia by inhibiting microglia-mediated inflammatory response in a rat model of ischemic stroke. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h followed by 24 h of reperfusion. Propofol (50 mg/kg/h) or vehicle was infused intravenously at the onset of reperfusion for 30 minutes. In vehicle-treated rats, MCAO resulted in significant cerebral infarction, higher neurological deficit scores and decreased time on the rotarod compared with sham-operated rats. Propofol treatment reduced infarct volume and improved the neurological functions. In addition, molecular studies demonstrated that mRNA expression of microglial marker Cd68 and Emr1 was significantly increased, and mRNA and protein expressions of proinflammatory cytokines tumor necrosis factor-α, interleukin-1β and interleukin-6 were augmented in the peri-infarct cortical regions of vehicle-treated rats 24 h after MCAO. Immunohistochemical study revealed that number of total microglia and proportion of activated microglia in the peri-infarct cortical regions were markedly elevated. All of these findings were ameliorated in propofol-treated rats. Furthermore, vehicle-treated rats had higher plasma levels of interleukin-6 and C-reactive protein 24 h after MCAO, which were decreased after treatment with propofol. These results suggest that propofol protects against focal cerebral ischemia via inhibition of microglia-mediated proinflammatory cytokines. Propofol may be a promising therapeutic agent for the treatment of ischemic stroke and other neurodegenerative diseases associated with microglial activation.
缺血性中风会引起小胶质细胞激活和促炎细胞因子释放,导致脑损伤扩大和临床预后不良。许多实验研究表明,异丙酚可以改善神经元损伤,但它的神经保护作用的确切机制仍不清楚。我们假设异丙酚通过抑制小胶质细胞介导的炎症反应,对缺血性中风大鼠模型发挥神经保护作用。将 Sprague-Dawley 大鼠进行大脑中动脉闭塞(MCAO)2 小时,然后再进行 24 小时的再灌注。在再灌注开始时,通过静脉内输注异丙酚(50mg/kg/h)或载体 30 分钟。在载体处理的大鼠中,与假手术组大鼠相比,MCAO 导致明显的脑梗死、更高的神经功能缺损评分和旋转棒上的时间减少。异丙酚治疗减少了梗死体积并改善了神经功能。此外,分子研究表明,在 MCAO 后 24 小时,载体处理的大鼠的小胶质细胞标志物 Cd68 和 Emr1 的 mRNA 表达显著增加,促炎细胞因子肿瘤坏死因子-α、白细胞介素-1β 和白细胞介素-6 的 mRNA 和蛋白表达增加。免疫组织化学研究显示,在梗死周围皮质区域的总小胶质细胞数量和激活小胶质细胞的比例明显升高。所有这些发现都在异丙酚处理的大鼠中得到改善。此外,MCAO 后 24 小时,载体处理的大鼠的血浆白细胞介素-6 和 C 反应蛋白水平较高,用异丙酚处理后降低。这些结果表明,异丙酚通过抑制小胶质细胞介导的促炎细胞因子来保护局灶性脑缺血。异丙酚可能是治疗缺血性中风和其他与小胶质细胞激活相关的神经退行性疾病的有前途的治疗剂。