荷载Akt基因的PEG-PLGA/DOPE纳米粒的制备及对大鼠缺血性脑损伤的影响

Preparation of PEG-PLGA/DOPE nanoparticles loading Akt genes and its effect on ischemic brain injury in rats

目的探讨荷载Akt基因的聚乙二醇-乳酸羟基乙酸共聚物/二油酰磷脂酰乙醇胺(PEG-PLGA/DOPE)纳米粒(Akt-NPs)对脑缺血-再灌注(I-R)诱导的大鼠海马CA1区神经细胞损伤及血红素加氧酶1(HO-1)、半胱天冬氨酸蛋白酶3(Caspase-3)表达的影响。方法通过复乳法制备PEG-PLGA/DOPE纳米粒并对其进行表征。将48只SD大鼠随机均分为假手术组(A组)、全脑I-R组(B组)、I-R+Akt-NPs组(C组)和I-R+空载PEG-PLGA/DOPE纳米粒组(D组)。采用焦油紫染色和TUNEL染色检测全脑I-R后5d各组大鼠海马CA1区神经细胞凋亡的情况,免疫印迹法检测各组HO-1和Caspase-3的表达。结果制备的纳米粒能够较好地荷载Akt基因。I-R后5d时,与A组相比,B组大鼠脑海马CA1区神经细胞凋亡率上升(P<0.05),HO-1表达减少(P<0.05),Caspase-3表达增加(P<0.05);与B组相比,C组大鼠脑海马CA1区神经细胞凋亡率下降(P<0.05),HO-1表达增加(P<0.05),Caspase-3表达减少(P<0.05)。结论 Akt-NPs减轻大鼠海马CA1区神经细胞的缺血性损伤作用与上调HO-1和下调Caspase-3表达有关。

Objective To explore the effect of PEG-PLGA/DOPE nanoparticles loading Akt genes（Akt-NPs） on cerebral ischemia-reperfusion（I-R） injury and expressions of heine oxygenaseq （HCI） and Caspase-3 in rat hippocarnpal CA1 region. Methods PEG-PLGA/DOPE nanoparticles were prepared by double emulsion method and exosyndromed. Forty-eight SD rats were equally randomized into four groups of A （ sham operated）, B （cerebral I-R injury）, C （given intraventricular injection with Akt-NPs after cerebral I-R injury） and D （given intraventricular injection with idle PEG-PLGA/DOPE nanoparticles after cerebral I-R injury）. The cresyl violet staining and TUNEL staining were used to detect the apoptosis of neurons in rat hippocampal CA1 region,and immunoblot was used to detect the expressions of HO-1 and Caspase-3 on the 5th day after I-R injury. Results - The prepared nanoparticles could be used to load Akt genes. Compared with group A, the apoptosis rate of neurons in rat hippocampal CA1 region was increased, the expression of HO-1 was decreased, and the expression of Caspase-3 was increased in group B on the 5th day after I-R injury（P〈0. 05）. Compared with group B, the apoptosis rate of neurons in rat hippocampal CA1 region was decreased, the expression of HO-1 was increased, and the expression of Caspase3 was decreased in group C on the 5th day after I-R injury（P〈0. 05）. Conclusion The alleviative effect of Akt-NPs on cerebral I-R injury in rat hippocampal CA1 region is related to upregulation of HOq and downregulation of Caspase-3.