Departments of Molecular Biology and Nutrition Sciences, Ariel University, Ariel 40700, Israel.
Nutrients. 2019 Jun 21;11(6):1396. doi: 10.3390/nu11061396.
() is a medicinal plant, traditionally used as an antidiabetic remedy. Previous studies demonstrated its beneficial properties in the treatment of insulin resistance. The aim of this study was to further clarify the effect of extract (SSE) on insulin signaling. Phosphoproteomic analysis, performed in 3T3-L1 adipocytes treated with SSE, revealed the activation of insulin receptor pathways. SSE increased Glut4-facilitated glucose uptake in adipocytes, with an additive effect between SSE and insulin. While the maximal effect of insulin on glucose uptake was found at days 15-16 of differentiation, SSE-induced glucose uptake was found at an earlier stage of differentiation. Inhibition of PI3K and Akt blocked SSE-dependent glucose uptake. Western blot analysis, performed on 3T3-L1 adipocytes and L6 myotubes, showed that in contrast to insulin action, Akt was only marginally phosphorylated by SSE. Furthermore, GSK3β and PRAS40 phosphorylation as well as glucose uptake were increased by the extract. SSE also induced the phosphorylation of ERK similar to insulin. In conclusion, SSE activates insulin signaling, although the upstream event mediating its effects should be further clarified. Identifying the active molecules in SSE may lead to the development of new agents for the treatment of insulin resistance.
（）是一种药用植物，传统上被用作抗糖尿病药物。先前的研究表明其在治疗胰岛素抵抗方面具有有益特性。本研究旨在进一步阐明 提取物（SSE）对胰岛素信号的影响。在经 SSE 处理的 3T3-L1 脂肪细胞中进行的磷酸蛋白质组学分析显示，胰岛素受体途径被激活。SSE 增加了脂肪细胞中 Glut4 促进的葡萄糖摄取，并且 SSE 与胰岛素具有相加作用。虽然胰岛素对葡萄糖摄取的最大作用发生在分化的第 15-16 天，但 SSE 诱导的葡萄糖摄取发生在分化的早期阶段。PI3K 和 Akt 的抑制阻断了 SSE 依赖性的葡萄糖摄取。在 3T3-L1 脂肪细胞和 L6 肌管上进行的 Western blot 分析表明，与胰岛素作用相反，Akt 仅被 SSE 轻微磷酸化。此外，GSK3β 和 PRAS40 磷酸化以及葡萄糖摄取均被提取物增加。SSE 还诱导类似于胰岛素的 ERK 磷酸化。总之，SSE 激活了胰岛素信号，尽管介导其作用的上游事件仍需进一步阐明。鉴定 SSE 中的活性分子可能会导致开发出治疗胰岛素抵抗的新药物。
