Zhang Xin, Kong Ying, Sun Yijie, Qian Zhiqiang, Gao Chenxue, Shi Xiaoxia, Li Shuangyue, Piao Yongjun, Piao Fengyuan
Department of Occupational and Environmental Health, Dalian Medical University, Dalian 116044, China; Department of Clinical Nutrition, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China.
Department of Biochemistry and Molecular Biology, Dalian, Liaoning 116044, China.
Brain Res. 2018 Oct 1;1696:1-9. doi: 10.1016/j.brainres.2018.04.028. Epub 2018 Apr 27.
We aimed to investigate the effects of bone marrow mesenchymal stem cell conditioned medium (BMSC-CM) in preventing 2,5-hexanedione (HD)-induced damage to motoneurons, and examined the molecular mechanisms that mediate these effects. VSC4.1 cells were exposed to 25 mM HD for 24 h followed by incubation with DMEM for 24 h. HD-treated cells were incubated with BMSC-CM at varied concentrations. Incubation with BMSC-CM ameliorated the decreased cell viability and reduced LDH release from cells exposed to HD. BMSC-CM suppressed the elevated number of autophagic vacuoles, cells with LC3 puncta, increased LC3-II/LC3-I ratio, and decreased p62 caused by HD exposure. BMSC-CM elevated NGF and p-TrkA expressions in HD-treated cells. Administration of NGF inhibited autophagy, an effect that was similar to that observed after BMSC-CM treatment; this effect was abolished by the addition of NGF-neutralizing antibodies. BMSC-CM or NGF elevated p-protein kinase B (Akt) and p-mammalian target of rapamycin (mTOR) in HD-exposed cells, which was interrupted by TrkA inhibitor, K252a and mTOR inhibitor, rapamycin. BMSC-CM prevented HD-induced autophagic cell damage in VSC4.1 cells. The neuroprotective effect of BMSC-CM appeared to be at least partly associated with its ability to trigger the NGF-phosphatidylinositol-3-kinase (PI3K)/Akt/mTOR signaling pathway.
我们旨在研究骨髓间充质干细胞条件培养基（BMSC-CM）对预防2,5-己二酮（HD）诱导的运动神经元损伤的作用，并探讨介导这些作用的分子机制。将VSC4.1细胞暴露于25 mM HD中24小时，然后用DMEM孵育24小时。用不同浓度的BMSC-CM孵育HD处理的细胞。用BMSC-CM孵育可改善HD处理细胞的活力降低和乳酸脱氢酶（LDH）释放减少的情况。BMSC-CM抑制了HD暴露引起的自噬空泡数量增加、具有LC3斑点的细胞数量增加、LC3-II/LC3-I比率升高以及p62降低。BMSC-CM提高了HD处理细胞中神经生长因子（NGF）和磷酸化TrkA（p-TrkA）的表达。给予NGF可抑制自噬，这一作用与BMSC-CM处理后观察到的作用相似；加入NGF中和抗体可消除这一作用。BMSC-CM或NGF提高了HD暴露细胞中磷酸化蛋白激酶B（Akt）和磷酸化哺乳动物雷帕霉素靶蛋白（mTOR）的水平，而TrkA抑制剂K252a和mTOR抑制剂雷帕霉素可阻断这一作用。BMSC-CM可预防HD诱导的VSC4.1细胞自噬性细胞损伤。BMSC-CM的神经保护作用似乎至少部分与其触发NGF-磷脂酰肌醇-3-激酶（PI3K）/Akt/mTOR信号通路的能力有关。
