Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, No. 199 of Donggang West Road, Lanzhou City, Gansu province 730000, PR China; Key Laboratory of Preclinical Study for New Drugs of Gansu Province, Lanzhou University, No. 199 of Donggang West Road, Lanzhou City, Gansu province 730000, PR China.
Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, No. 199 of Donggang West Road, Lanzhou City, Gansu province 730000, PR China.
Exp Gerontol. 2018 Jul 15;108:77-86. doi: 10.1016/j.exger.2018.04.005. Epub 2018 Apr 9.
Changes in mitochondrial structure and function are the initial factors of cell aging. Spermidine has an antiaging effect, but its effect on neuronal aging and mitochondrial mechanisms is unclear. In this study, mouse neuroblastoma (N2a) cells were treated with d‑galactose (d‑Gal) to establish cell aging to investigate the antiaging effect and mechanisms of spermidine. Changes in the cell cycle and β-galactosidase activity were analyzed to evaluate the extent of cell aging. Stabilities of mitochondrial mRNA and mitochondrial membrane potential (MMP) were evaluated in the process of cell aging under different treatments. The mitochondrial function was also evaluated using the Seahorse Metabolic Analysis System combined with ATP production. The unfolded protein response (UPR) of the N2a cells was analyzed under different treatments. Results showed that spermidine pretreatment could delay the cell aging and could maintain the mitochondrial stability during d‑Gal treatment. Spermidine increased the proportion of cells in the S phase and maintained the MMP. The oxygen utilization and ATP production in the N2a cells were reduced by d‑Gal treatment but were partially rescued by the spermidine pretreatment. Spermidine ameliorated the N2a cell aging by promoting the autophagy and inhibiting the apoptosis except the UPR. These results showed that spermidine could ameliorate the N2a cell aging by maintaining the mitochondrial mRNA transcription, MMP and oxygen utilization during the d‑Gal treatment.
线粒体结构和功能的改变是细胞衰老的最初因素。亚精胺具有抗衰老作用，但它对神经元衰老和线粒体机制的影响尚不清楚。在这项研究中，用 D-半乳糖（D-Gal）处理小鼠神经母细胞瘤（N2a）细胞以建立细胞衰老模型，以研究亚精胺的抗衰老作用和机制。分析细胞周期和β-半乳糖苷酶活性的变化，以评估细胞衰老的程度。在不同处理过程中，评估衰老细胞中线粒体 mRNA 和线粒体膜电位（MMP）的稳定性。还使用 Seahorse 代谢分析系统结合 ATP 产生来评估线粒体功能。在不同处理下分析 N2a 细胞的未折叠蛋白反应（UPR）。结果表明，亚精胺预处理可以延缓细胞衰老，并在 D-Gal 处理过程中维持线粒体稳定性。亚精胺增加了 S 期细胞的比例并维持了 MMP。D-Gal 处理会降低 N2a 细胞的耗氧量和 ATP 产生，但亚精胺预处理部分挽救了这一结果。除了 UPR，亚精胺通过促进自噬和抑制细胞凋亡来改善 N2a 细胞衰老。这些结果表明，亚精胺通过在 D-Gal 处理过程中维持线粒体 mRNA 转录、MMP 和耗氧量，来改善 N2a 细胞衰老。
