芍药苷对局灶性大鼠脑缺血再灌注脑组织中SOD、Nrf2表达的影响及神经保护作用

Effect of paeoniflorin on superoxide dismutase and nuclear factor E2-related factor 2 expression in brain tissues of rats with middle cerebral artery occlusion and its neuroprotection

摘要:

目的：研究芍药苷（paeoniflorin，PF）对局灶性大鼠脑缺血再灌注模型脑组织中超氧化物歧化酶（superoxide dismutase，SOD）、核因子E2相关因子2（nuclear factor E2-related factor 2，Nrf2）在各时间点的表达情况及其神经保护作用。方法：将108只健康成年雄性SD大鼠随机分为假手术组、模型组、给药组，每组在3、6、12、24、48、72 h进行神经功能评分，黄嘌呤氧化酶法测定SOD活性，RT-PCR、Western blot技术测定Nrf2 mRNA、蛋白分子的表达。结果：与假手术组相比，模型组的神经功能评分明显升高，SOD活性明显下降，Nrf2的表达有所增加，差异具有统计学意义（P<0.05）；与模型组相比，给予PF（20 mg/kg）能使模型组的神经功能评分降低，SOD活性有所升高，Nrf2的表达持续上调，差异具有统计学意义（P<0.05）。结论：PF能通过提高机体消除自由基能力和增加Nrf2表达来减轻局灶性脑缺血再灌注损伤后自由基引起的氧化损伤作用，从而对缺血性脑组织起到脑保护作用。

Abstract:

Objective：To investigate the expression of paeoniflorin（PF） on superoxide dismutase（SOD） and nuclear factor E2-related factor 2（Nrf2） in brain tissue of rats with middle cerebral artery occlusion at each time point and its neuroprotection. Methods：Totally 108 healthy adult male SD rats were randomized into sham operation group，model group，experimental group. Modified neurological severity score was detected at 3，6，12，24，48，72 h. Activity of SOD was detected by xanthine oxidase technique. Nrf2 mRNA and protein expression was detected by RT-PCR and Western blot. Results：Compared with those in sham operation group，the modified neurological severity score was significantly higher，SOD activity was significantly decreased and Nrf 2 expression was increased in model group with statistically differences（P<0.05）. Compared with those in model group，giving paeoniflorin（20 mg/kg） can make the modified neurological severity score decrease，SOD activity increase，Nrf2 expression increase with statistically differences（P<0.05）. Conclusion：Paeoniflorin can reduce the oxidative damage in brain tissues of rats with middle cerebral artery occlusion caused by free radicals by improving the capacity of body eliminating free radicals and increasing the expression of Nrf2.