丁苯酞对局灶性脑缺血再灌注大鼠海马CA_1区神经细胞凋亡、SIRT1及PGC-1α表达的影响

Effects of Butylphthalide on the Expression of the Neuronal Apoptosis,SIRT1 and PGC-1α in Hippocampus CA_1 of Rats with Focal Cerebral Ischemia-reperfusion

目的观察丁苯酞(NBP)注射液对局灶性脑缺血再灌注大鼠缺血侧海马CA1区神经细胞凋亡、沉默信息调节因子2相关酶1(SIRT1)及过氧化体增殖物激活型受体γ共激活因子1α(PGC-1α)表达的影响,探讨NBP的脑保护机制。方法雄性SD大鼠160只,随机分为假手术组、脑缺血组、NBP高剂量后处理组(高剂量组)、NBP中剂量后处理组(中剂量组)、NBP低剂量后处理组(低剂量组),采用改良的Zea Longa线栓法制作局灶性脑缺血再灌注大鼠模型,后四组大鼠分为缺血2 h再灌注6 h、12 h、24 h、48 h、72 h 5个时间点,应用TUNEL法检测神经细胞凋亡;免疫组织化学染色法和实时荧光定量PCR检测SIRT1、PGC-1α的表达。结果与脑缺血组比较,NBP后处理组各时间点凋亡细胞数减少,SIRT1、PGC-1α阳性细胞数增多(P<0.05)。与低、中剂量组比较,高剂量组凋亡细胞数显著减少,SIRT1、PGC-1α阳性细胞数显著增多(P<0.05);与低剂量组比较,中剂量组SIRT1阳性细胞数除再灌注6 h外,其余时间点均增高(P<0.05),PGC-1α阳性细胞数除再灌注6 h、72 h外,其余时间点均增高(P<0.05)。与脑缺血组比较,高剂量组各时间点SIRT1和PGC-1αmRNA的表达增多(P<0.05)。结论 NBP抑制细胞凋亡,减轻大鼠脑缺血再灌注损伤,发挥脑保护作用,其机制可能与上调SIRT1和PGC-1α的表达有关。

Aim To observe the effect of butylphthalide（ NBP） injection on the expression of the neuronal apoptosis,SIRT1 and PGC-1α in hippocampus CA1 of rats with focal cerebral ischemia-reperfusion,then explore the mechanisms of neuroprotection from NBP. Methods 160 male SD rats were randomly divided into sham group,middle cerebral artery occlusion group（ MCAO group）,high dose NBP post-treatment group（ high dose group）,middle dose NBP post-treatment group（ middle dose group） and low dose NBP post-treatment group（ low dose group）. Focal cerebral ischemia reperfusion model was established with the improved Zea Longa method. The later four groups were further divided into 6 h,12 h,24 h,48 h and 72 h point after model. TUNEL staining was used to observe the expression of neuronal apoptosis. Immunohistochemistry and quantitative real-time PCR were used to observe the expression of SIRT1 and PGC-1α. Results Compared with MCAO group,the number of apoptotic cells were significantly decreased and the number of SIRT1 and PGC-1α positive cells were significantly increased in NBP post-treatment group at each time point（ P0.05）.Compared with low dose and middle dose group,the number of apoptotic cells were significantly decreased and the number of SIRT1 and PGC-1α positive cells were significantly increased in high dose group（ P0.05）. Compared with low dose group,the number of SIRT1 positive cells were significantly increased except for 6 h and the number of PGC-1α positive cells were significantly increased except for 6 h and 72 h in middle dose group at related point（ P0.05）. Compared with MCAO group,the expression of SIRT1 and PGC-1α mRNA were significantly increased in high dose group at each time point（ P0.05）. Conclusion The findings demonstrate that NBP can inhibit cell apoptosis and relieve the brain damage of focal cerebral ischemia reperfusion in rats,which may significantly associate with the up-regulating of SIRT1 and PGC-1α.