Huang Zhixin, Zhang Zhijian, Zhang Yang, Yu Xiaolan, Wu Xiuli
Department of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China.
Sheng Wu Gong Cheng Xue Bao. 2010 May;26(5):671-8.
The expression of NF-kappaB is considered to be involved in the progress of neurodegeneration. It has been reported that Nanog can suppress the expression of NF-kappaB. To inspect and verify this finding, we constructed lentivirus (LV) vector that overexpressed the Nanog gene, infected mouse mesenchymal stem cells (mMSCs), and examined the influence of Nanog overexpression on NF-kappaB gene expression. The plasmid pNL-Nanog-IRES2-EGFP was constructed by double digestion and genetic recombination. Sequencing results confirmed that our cloned Nanog gene in the PNL-Nanog-IRES2-EGFP plasmid was consistent with the sequence reported in the GenBank. The three plasmids: pNL-Nanog-IRES2-EGFP, HELPER, and VSVG were cotransfected into 293T cells to produce LV particles. After co-transfection of the three lentiviral plasmids, green fluorescence was observed confirming successful transfection. The mMSCs were infected by the LV and the expression of Nanog was then also verified by the presence of green fluorescence. Nanog expression levels in the mMSCs were examined using Western blotting. Expression of NF-kappaB was also examined using RT-PCR and Western blotting, and in addition with fluorescent microscope after immunocytochemical staining. The levels of Nanog protein expression in Nanog-mMSCs were significantly increased, and the levels of NF-kappaB mRNA and protein expression in Nanog-infected mMSCs were significantly lower than those of Mock-mMSCs and the mMSCs control groups. Our findings suggest that mMSCs genetically modified to overexpress Nanog can lead to the suppression of NF-kappaB expression. This suppression of NF-kappaB could have important implications for the treatment of neurodegeneration, and hence further scientific investigations of these interactions will have significant impact on future clinical attempts to attenuate disease progression.
核因子-κB(NF-κB)的表达被认为与神经退行性变的进展有关。据报道,Nanog可抑制NF-κB的表达。为了检验和验证这一发现,我们构建了过表达Nanog基因的慢病毒(LV)载体,感染小鼠间充质干细胞(mMSCs),并检测Nanog过表达对NF-κB基因表达的影响。通过双酶切和基因重组构建质粒pNL-Nanog-IRES2-EGFP。测序结果证实,我们在PNL-Nanog-IRES2-EGFP质粒中克隆的Nanog基因与GenBank中报道的序列一致。将三种质粒:pNL-Nanog-IRES2-EGFP、HELPER和VSVG共转染到293T细胞中以产生LV颗粒。三种慢病毒质粒共转染后,观察到绿色荧光,证实转染成功。mMSCs被LV感染,然后通过绿色荧光的存在也验证了Nanog的表达。使用蛋白质免疫印迹法检测mMSCs中Nanog的表达水平。还使用逆转录-聚合酶链反应(RT-PCR)和蛋白质免疫印迹法检测NF-κB的表达,此外在免疫细胞化学染色后用荧光显微镜观察。Nanog-mMSCs中Nanog蛋白表达水平显著升高,Nanog感染的mMSCs中NF-κB mRNA和蛋白表达水平显著低于Mock-mMSCs和mMSCs对照组。我们的研究结果表明,经基因改造过表达Nanog的mMSCs可导致NF-κB表达的抑制。这种对NF-κB的抑制可能对神经退行性变的治疗具有重要意义,因此对这些相互作用的进一步科学研究将对未来减轻疾病进展的临床尝试产生重大影响。