Liou Chian-Jiun, Len Wen-Bin, Wu Shu-Ju, Lin Chwan-Fwu, Wu Xin-Ling, Huang Wen-Chung
Department of Nursing, Chang Gung University of Science and Technology, 261 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan, ROC.
Department of Nutrition and Health Sciences, Chang Gung University of Science and Technology, 261 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan, ROC.
J Ethnopharmacol. 2014 Dec 2;158 Pt A:310-6. doi: 10.1016/j.jep.2014.10.046. Epub 2014 Oct 31.
The fruits of Vitex rotundifolia L. are widely used to treat inflammation of the airway in Traditional Chinese medicine. Previous studies found that casticin, isolated from Vitex rotundifolia, could induce apoptosis of tumor cells. In this study, we evaluated the anti-inflammatory effects of casticin and its underlying molecular mechanism in lipopolysaccharide (LPS)-stimulated macrophages.
RAW264.7 cells were pretreated with various concentrations of casticin (0.3-10μM), and then treated with LPS to induce inflammation. We assayed the levels of proinflammatory cytokines and prostaglandin E2 (PGE2) using ELISA, and examined the protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and heme oxygenase (HO)-1 by Western blot. We also investigated the anti-inflammatory molecular mechanism by analyzing inflammatory-associated signaling pathways, including the nuclear transcription factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways.
We found casticin inhibited the levels of nitric oxide and PGE2, and decreased the production of proinflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α). In addition, iNOS and COX-2 expression levels were suppressed and casticin increased HO-1 and Nrf2 production in a concentration-dependent manner. Furthermore, casticin significantly inhibited NF-κB subunit p65 proteins in the nucleus and decreased Akt and MAPK activation.
These results suggest that the anti-inflammatory effect of casticin is due to inhibition of proinflammatory cytokines and mediators by blocking the NF-κB, Akt, and MAPK signaling pathways.
中药中，蔓荆子果实广泛用于治疗气道炎症。既往研究发现，从蔓荆子中分离得到的紫花牡荆素可诱导肿瘤细胞凋亡。本研究中，我们评估了紫花牡荆素在脂多糖（LPS）刺激的巨噬细胞中的抗炎作用及其潜在分子机制。
RAW264.7细胞用不同浓度的紫花牡荆素（0.3 - 10μM）预处理，然后用LPS处理以诱导炎症。我们使用酶联免疫吸附测定法（ELISA）检测促炎细胞因子和前列腺素E2（PGE2）的水平，并通过蛋白质免疫印迹法检测诱导型一氧化氮合酶（iNOS）、环氧化酶（COX）-2和血红素加氧酶（HO）-1的蛋白表达。我们还通过分析炎症相关信号通路，包括核转录因子κB（NF-κB）和丝裂原活化蛋白激酶（MAPK）通路，来研究抗炎分子机制。
我们发现紫花牡荆素抑制一氧化氮和PGE2水平，并减少促炎细胞因子如白细胞介素（IL）-1β、IL-6和肿瘤坏死因子α（TNF-α）的产生。此外，iNOS和COX-2表达水平受到抑制，紫花牡荆素以浓度依赖方式增加HO-1和Nrf2的产生。此外，紫花牡荆素显著抑制细胞核中NF-κB亚基p65蛋白，并降低Akt和MAPK的激活。
这些结果表明，紫花牡荆素的抗炎作用是通过阻断NF-κB、Akt和MAPK信号通路来抑制促炎细胞因子和介质实现的。
