IGF-1抑制SIRT1表达与活性介导椎间盘纤维环细胞衰老的机制研究

IGF-1 induced intervertebral disc annulus fibrosus cell aging through the inhibition of SIRT1 activity

中文关键词:  椎间盘纤维环细胞  IGF-1  SIRT1  椎间盘衰老

英文关键词:Annulus fibrosus cells  IGF-1  SIRT1  Intervertebral disc aging

中文摘要:

  【摘要】 目的：探讨胰岛素样生长因子-1（insulin-like growth factor-1，IGF-1）通过调控沉默信息调节因子sirtuin 1（SIRT1）活性介导椎间盘细胞衰老的机制。方法：选取8周龄Spargue-Dawley（SD）雌性大鼠，分离椎间盘组织，体外培养椎间盘纤维环（annulus fibrosus，AF）细胞，加入不同浓度外源IGF-1（0、1、10、50、100ng/mL）进行培养，通过β-半乳糖苷酶（SA-β-Gal）染色、细胞增殖实验、细胞迁移实验等实验检测不同浓度IGF-1对AF细胞的影响，并通过Western blot进一步探讨IGF-1通过调控SIRT1活性介导AF细胞衰老的分子机制。结果：不同浓度外源IGF-1处理后，SA-β-Gal染色和Western blot结果均显示IGF-1呈浓度依赖性AF细胞衰老；CCK-8实验显示低浓度IGF-1促进AF细胞的增殖较为明显；Transwell实验结果表明低浓度IGF-1可以促进AF细胞的迁移，而高浓度IGF-1对AF细胞的迁移能力没有显著影响；Western blot结果进一步表明IGF-1可以下调SIRT1的表达，并促进p53蛋白的乙酰化。结论：IGF-1可通过抑制SIRT1的表达和活性促进AF细胞的衰老。

英文摘要:

  【Abstract】 Objectives: To investigate the mechanism of insulin-like growth factor 1(IGF-1) in mediating intervertebral disc cell aging through regulating the activity of the silent information regulator sirtuin 1(SIRT1). Methods: The intervertebral disc tissues of eight-week old female Spargue Dawley(SD) rats were dissected, from which annulus fibrosus(AF) cells were isolated and cultured in vitro. The effects of IGF-1 on the aging of AF cells were studied by β-galactosidase(SA-β-Gal) staining, cell proliferation assays, and cell migration experiments, in exposure to different concentrations of recombinant rat IGF-1(0, 1, 10, 50, 100ng/mL) in culture. The molecular mechanism of IGF-1 on AF cells was further explored by Western blot analysis. Results: After treatment with exogenous IGF-1 at different concentrations, SA-β-Gal staining and western blot results showed that IGF-1 promoted AF cell aging in a concentration-dependent manner. The CCK-8 analysis showed that low concentrations of IGF-1 significantly induced AF cell proliferation. Transwell assay results showed that low concentrations of IGF-1 profoundly enhanced the migratory capability of AF cells, whereas IGF-1 at high concentrations demonstrated no significant effect on AF cell migration. Western blot results showed that IGF-1 could downregulate the expression of SIRT1 and elevate the acetylation of p53. Conclusions: IGF-1 can promote AF cell aging though inhibiting SIRT1 expression and activity.