[关键词]
[摘要]
目的 研究羊栖菜多糖(SFPS)发挥抗氧化、抗衰老的作用机制。方法 采用实时荧光定量PCR(qRT-PCR)和Western blotting法检测不同月龄雄性小鼠和ig给予SFPS的老年雄性小鼠肝脏中c-Jun氨基末端激酶1/2(JNK1/2)的表达;RT-PCR特异性区分JNK的各蛋白异构体,并检测各异构体在ig SFPS或生理盐水的自然衰老小鼠肝脏中的表达水平;免疫共沉淀和ARE-荧光素酶报告基因检测JNK激活转录因子NF-E2相关因子2(Nrf2)/ARE信号通路的分子机制。结果 JNK1/2的表达水平与小鼠的衰老进程呈负相关,JNK1-β2、JNK2-α1、JNK2-β2 mRNA表达水平在小鼠衰老过程中显著下降,而ig给予SFPS能够显著提高老年小鼠JNK1-β2(5.4×104)的表达水平,JNK(5.4×104)蛋白与抗氧化因子Nrf2存在相互作用,且JNK1-β2(5.4×104)能够显著激活Nrf2/ARE信号通路。结论 JNK1-β2、JNK2-α1和JNK2-β2与衰老进程负相关,含有C-terminal tail的JNK1-β2能够显著激活Nrf2/ARE抗氧化信号通路。SFPS能显著提高老年小鼠JNK1-β2(5.4×104)和Nrf2/ARE信号通路的表达水平,进而提高机体的抗氧化能力,最终延缓小鼠的衰老进程。
[Key word]
[Abstract]
Objective To study the mechanisms of anti-oxidation and anti-aging of Sargassum fusiforme polysaccharides (SFPS). Methods qRT-PCR and Western blotting were utilized to detect the expression of c-Jun-N-terminal kinase 1/2 (JNK1/2) in male mice with different ages and in the old male mice fed with SFPS. The JNK isoforms were specifically distinguished by RT-PCR and the expression levels of each isoform in the liver of mice by ig administration of SFPS or normal saline were measured. Finally, the mechanism of JNK activating Nrf2/ARE signaling pathway was determined by co-immunoprecipitation and ARE-luciferase reporter gene assay. Results The expression levels of JNK1/2 were negatively correlated with aging process. JNK1-β2, JNK2-α1, and JNK2-β2 played important roles in aging process. The mRNA expression level of JNK1-β2, JNK2-α1, and JNK2-β2 were significantly decreased in mice aging process, and the protein expression levels of JNK1-β2 (5.4×104) were significantly upregulated by long-term diet with SFPS. The JNK1-β2 (5.4×104) protein interacted with anti-oxidant factor Nrf2, and significantly activated Nrf2/ARE signaling pathway. Conclusion JNK1-β2, JNK2-α1 and JNK2-β2 had negative correlation with aging process, and the expression level of JNK1-β2 (5.4×104) in aged mice were obviously promoted by long-term diet with SFPS. As JNK1-β2 containing C-terminal tail can interact with Nrf2 and activate the NRF2/ARE signaling pathway, therefore, it was suggested that SFPS can improve the overall anti-oxidant capacity and retard aging process by activating of the JNK1-β2/Nrf2/ARE signaling pathway.
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[基金项目]
国家自然科学基金资助项目(31470430);青年科学基金资助项目(31301148);浙江省科技计划项目(2017C32103);浙江省新苗人才计划(2017R426014)