Liu Yunyun, Yang Xingyi, Lei Qingfeng, Li Zhong, Hu Jingyang, Wen Xiaojun, Wang Huijun, Liu Zhonglin
Department of Neurology, The Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
Cell Mol Neurobiol. 2015 Aug;35(6):841-8. doi: 10.1007/s10571-015-0178-6. Epub 2015 Mar 17.
Gene therapy that targets the ROCK2 gene has yielded promising results in the treatment of AD. Our previous study indicated that PEG-PEI/siROCK2 could effectively suppress ROCK2 mRNA expression and showed a promising prospect for the treatment of Alzheimer's disease. However, the ability of PEG-PEI/siROCK2 to reduce Aβ-induced cytotoxicity is unknown. To investigate the effect of PEG-PEI/siROCK2 against Aβ42-induced neurotoxicity, primary cultured cortical neurons were pretreated with PEG-PEI/siROCK2 for 24 h and then treated with 5 μM Aβ42 for 24 h. We found that PEG-PEI/siROCK2 increased the cell viability and reduced the number of apoptotic cells induced by Aβ42, as measured using an MTT assay and Annexin V/PI staining. A further study revealed that PEG-PEI/siROCK2 can activate p-Akt, and treatment with the PI3K inhibitor LY294002 attenuated the neuroprotective effects. These results suggest that PEG-PEI/siROCK2 prevents Aβ42-induced neurotoxicity and that the activation of PI3K/Akt pathway is involved in neuroprotection. Taken together, these findings shed light on the role of PEG-PEI/siROCK2 as a potential therapeutic agent for AD.
靶向ROCK2基因的基因疗法在阿尔茨海默病（AD）治疗中已取得了有前景的成果。我们之前的研究表明，聚乙二醇-聚乙烯亚胺/小干扰RNA（PEG-PEI/siROCK2）能够有效抑制ROCK2信使核糖核酸（mRNA）的表达，并显示出治疗阿尔茨海默病的广阔前景。然而，PEG-PEI/siROCK2降低β淀粉样蛋白（Aβ）诱导的细胞毒性的能力尚不清楚。为了研究PEG-PEI/siROCK2对Aβ42诱导的神经毒性的影响，原代培养的皮质神经元先用PEG-PEI/siROCK2预处理24小时，然后用5微摩尔/升的Aβ42处理24小时。我们发现，通过噻唑蓝（MTT）法和膜联蛋白V/碘化丙啶（Annexin V/PI）染色检测，PEG-PEI/siROCK2提高了细胞活力，并减少了Aβ42诱导的凋亡细胞数量。进一步的研究表明，PEG-PEI/siROCK2可以激活磷酸化蛋白激酶B（p-Akt），而使用磷脂酰肌醇-3-激酶（PI3K）抑制剂LY294002处理可减弱这种神经保护作用。这些结果表明，PEG-PEI/siROCK2可预防Aβ42诱导的神经毒性，且PI3K/Akt信号通路的激活参与了神经保护过程。综上所述，这些发现揭示了PEG-PEI/siROCK2作为AD潜在治疗药物的作用。
