Henan University of Chinese Medicine, Zhengzhou, 450046, China.
Mol Biol Rep. 2020 Sep;47(9):6899-6918. doi: 10.1007/s11033-020-05746-3. Epub 2020 Sep 6.
The aim of the work was to investigate the effects of acacetin on endothelial dysfunction and aortic fibrosis in insulin-resistant SHR rats and explore its mechanism. Seven-week-old male spontaneously hypertensive rats (SHR) were selected to establish a rat model of hypertension with insulin resistance induced by 10% fructose. The nuclear factor kappa B p65 (NF-κB p65) and Collagen I were observed by Immunohistochemistry. Immunofluorescence was used to observe estrogen receptor-alpha (ERα), estrogen receptor-beta (ERβ), and G protein-coupled receptor 30 (GPR30). Western blotting was used to detect interleukin (IL-1β), Arginase 2 (ARG2), Nostrin, endothelial nitric oxide synthase (eNOS), TGF-β, Smad3, ERK pathway proteins such as p-c-Raf, p-MEK1/2, p-ERK, ERK, p-P90RSK and p-MSK1. We found that acacetin did have an improvement on endothelial dysfunction and fibrosis. Meanwhile, it was also found to have a significant effect on the level of estrogen in this model by accident. Then, the experiment of uterine weight gain in mice confirmed that acacetin had a certain estrogen-like effect in vivo and played its role through the estrogen receptors pathway. In vitro experience HUVEC cells were stimulated with 30 mM/L glucose and 100 mM/L NaCl for 24 h to establish the endothelial cell injury model. HUVEC cells were treated with 1 μM/L estrogen receptors antagonist (ICI 182780) for 30 min before administration. Cell experiments showed that acacetin could reduce the apoptosis of HUVEC cells, the levels of inflammatory cytokines and the expression of TGF-β, Collagen I and Smad3 in endothelial cell injury model. After treatment with ICI 182780, the improvement of acacetin was significantly reversed. The results showed that acacetin relieved endothelial dysfunction and reduced the aortic fibrosis in insulin-resistant SHR rats by reducing the release of inflammatory factors and improving vasodilatory function through estrogen signaling pathway.
本研究旨在探讨白杨素对胰岛素抵抗型 SHR 大鼠血管内皮功能障碍和主动脉纤维化的影响，并探讨其作用机制。选择 7 周龄雄性自发性高血压大鼠（SHR），建立由 10%果糖诱导的高血压合并胰岛素抵抗大鼠模型。采用免疫组化法观察核因子κB p65（NF-κB p65）和胶原 I 的表达，免疫荧光法观察雌激素受体-α（ERα）、雌激素受体-β（ERβ）和 G 蛋白偶联受体 30（GPR30）的表达，Western blot 法检测白细胞介素（IL-1β）、精氨酸酶 2（ARG2）、Nostrin、内皮型一氧化氮合酶（eNOS）、转化生长因子-β（TGF-β）、Smad3、细胞外信号调节激酶（ERK）通路蛋白 p-c-Raf、p-MEK1/2、p-ERK、ERK、p-P90RSK 和 p-MSK1 的表达。结果发现，白杨素确实可以改善血管内皮功能障碍和纤维化，同时还意外地发现其对该模型中雌激素水平有显著影响。随后，通过对小鼠子宫重量增加的实验证实，白杨素有一定的体内雌激素样作用，并通过雌激素受体途径发挥作用。体外经验用 30 mM/L 葡萄糖和 100 mM/L NaCl 刺激人脐静脉内皮细胞（HUVEC）24 h 建立内皮细胞损伤模型，在给药前用 1 μM/L 雌激素受体拮抗剂（ICI 182780）处理 30 min。细胞实验结果表明，白杨素可降低 HUVEC 细胞凋亡、内皮细胞损伤模型中炎症细胞因子水平及 TGF-β、胶原 I 和 Smad3 的表达。用 ICI 182780 处理后，白杨素的改善作用明显逆转。结果表明，白杨素通过雌激素信号通路减少炎症因子的释放，改善血管舒张功能，缓解胰岛素抵抗型 SHR 大鼠的血管内皮功能障碍，减少主动脉纤维化。
