Laboratory of Immunology and Signal Transduction, Department of Biology, Chaminade University, Honolulu, Hawaii 96816, USA.
Phytother Res. 2012 Dec;26(12):1934-41. doi: 10.1002/ptr.4652. Epub 2012 Apr 4.
Kava ('Awa) is a traditional water-based beverage in Pacific island communities, prepared from the ground root and stems of Piper methysticum. Kava use is associated with an ichthyotic dermatitis and delayed type hypersensitivity reactions. In the current study we collated preparative methodologies from cultural practitioners and recreational kava users in various Pacific communities. We standardized culturally informed aqueous extraction methods and prepared extracts that were subjected to basic physicochemical analysis. Mast cells exposed to these extracts displayed robust intracellular free calcium responses, and concomitant release of proinflammatory mediators. In contrast, mast cells were refractory to single or combinatorial stimulation with kavalactones, including methysticin, dihydromethysticin and kavain. Moreover, we reproduced a traditional modification of the kava preparation methodology, pre-mixing with the mucilage of Hibiscus tiliaceus, and observed its potentiating effect on the activity of aqueous extracts in mast cells. Taken together, these data indicate that water extractable active ingredients may play a role in the physiological and pathophysiological effects of kava, and suggests that mast cell activation may be a mechanistic component of kava-related skin inflammations.
卡瓦（“阿瓦”）是太平洋岛屿社区的一种传统的水基饮料，由 Piper methysticum 的根茎制成。卡瓦的使用与鱼鳞皮肤病和迟发型超敏反应有关。在目前的研究中，我们汇集了来自不同太平洋社区的文化从业者和娱乐性卡瓦使用者的制备方法。我们标准化了基于文化的水提取方法，并制备了提取物，然后对其进行了基本的物理化学分析。暴露于这些提取物的肥大细胞显示出强烈的细胞内游离钙反应，以及伴随的促炎介质释放。相比之下，肥大细胞对包括 methysticin、dihydromethysticin 和 kavain 在内的单一或组合的卡瓦内酯刺激无反应。此外，我们重现了卡瓦制备方法的传统改良，即与芙蓉 Hibiscus tiliaceus 的粘液预先混合，并观察到其对肥大细胞中水性提取物活性的增强作用。综上所述，这些数据表明，可水提取的活性成分可能在卡瓦的生理和病理生理作用中发挥作用，并表明肥大细胞激活可能是卡瓦相关皮肤炎症的机制组成部分。
