目的 基于甜味受体整合中药“效味”和“滋味”探索玉竹Polygonatum odoratum甘味药性物质基础，为中药药性物质研究提供新视角。方法 以多糖、皂苷、黄酮成分为玉竹甘味药性物质筛选对象，分析其对“阴虚”小鼠体质量、体温、食量、饮水量、大便含水量、皮肤含水量及Na⁺, K⁺-ATP酶、Ca²⁺, Mg²⁺-ATP酶活性和水通道蛋白1（aquaporin 1，AQP1）、AQP3 mRNA表达量的影响，基于“效味”探索玉竹甘味药性物质；以典型甘、苦、辛、酸、咸味中药建立中药“五味”标准，利用电子舌技术及主成分分析法（principal component analysis，PCA），分别比较玉竹多糖、皂苷、黄酮与中药“五味”的欧式距离及投射的区域，基于“滋味”探索玉竹甘味药性物质。将基于“效味”和“滋味”相同的甘味药性物质确定为玉竹甘味药性物质基础，并采用整体动物考察其对胰高血糖素样肽-1（glucagon-like peptide-1，GLP-1）分泌的影响，分子对接考察甘味药性物质与甜味受体的结合性，以此揭示效味、滋味与甜味受体的关联性。结果 与“阴虚”模型组比较，玉竹多糖、皂苷组小鼠的体质量、食量、饮水量、大便含水量、皮肤含水量及Na⁺, K⁺-ATP酶、Ca²⁺, Mg²⁺-ATP酶活性和AQP1、AQP3 mRNA表达量均表现出明显的回调（P＜0.05），而玉竹黄酮组小鼠的回调作用不明显；电子舌结果显示，玉竹多糖、皂苷与甘味中药的欧式距离最小，而玉竹黄酮与苦味中药的欧式距离最小；同时，玉竹皂苷投射到甘味中药区域，多糖则投射到辛味和甘味中药2个区域，而黄酮投射到苦味中药区域。动物实验进一步显示，与模型组比较，玉竹皂苷、多糖可明显促进GLP-1的分泌（P＜0.05）；分子对接结果显示，玉竹皂苷分子与鼠源、人源的甜味受体的结合能均小于−7.0 kJ/mol。结论 皂苷为玉竹“甘味”的药性物质基础，基于甜味受体整合中药“效味”和“滋味”可用于中药甘味药性物质研究。

Objective To explore the material basis of “sweet” medicinal properties of Yuzhu (Polygonatum odoratum) based on the sweet receptors to integrate “effective taste” and “taste” of traditional Chinese medicine (TCM), in order to provide a new perspective for the research of material basis of medicinal properties in TCM. Methods The polysaccharides, saponins, and flavonoids were selected as the screening objects for material basis of “sweet” medicinal properties of P. odoratum, to analyze the effects of them on body weight, body temperature, food intake, water intake, stool water content and skin water content, activities of Na⁺,K⁺-ATPase and Ca²⁺, Mg²⁺-ATPase, mRNA expression levels of aquaporin aquaporin 1 (AQP1) and AQP3 of mice with “yin deficiency”, to determine the material basis of “sweet” medicinal properties of P. odoratum from the perspective of “effective taste”. The standard of “five tastes” of TCM was established based on typical sweet, bitter, pungent, sour and salty TCM. The Euclidene distance and projection area of polysaccharides, saponins and flavones and “five tastes” of TCM were compared by electronic tongue technique and principal component analysis (PCA). The medicinal substance of P. odoratum based on “taste” was determine. Finally, the same substances of “sweet” medicinal properties based on “effective taste” and “taste” was selected as the material basis of “sweet” medicinal properties of P. odoratum, and to investigate its effect on glucagon-like peptide-1 (GLP-1) secretion. Molecular docking was conducted to investigate the binding properties of “sweet” medicinal properties substances and sweet taste receptors, so as to reveal the relationship between “effective taste”, “taste” and sweet taste receptors.Results Compared with the “yin deficiency” model group, the body weight, food intake, water intake, stool moisture content and skin moisture content, activities of Na⁺, K⁺-ATPase and Ca²⁺, Mg²⁺-ATPase, mRNA expression levels of AQP1 and AQP3 of the mice in the polysaccharide and saponin groups were showed significant callback effect (P < 0.05), while the callback effect of flavonoid group was not obvious. The results of the electronic tongue showed that the Euclidean distance between polysaccharides, saponins and sweet TCMs were the smallest, while that of flavonoids and bitter TCMs was the smallest; At the same time, saponins projected to the area of sweet TCMs, polysaccharides projected to the two areas of pungent and sweet TCMs, and flavonoids projected to the areas of the bitter TCM area. Animal experiments further showed that compared with the model group, saponins and polysaccharides could significantly promote the secretion of GLP-1 (P < 0.05). Molecular docking results showed that the binding scores of saponins to mice and human sweet receptors were less than −7.0 kJ/mol. Conclusion The saponins are the material basis of “sweet” medicinal basis of P. odoratum. Based on the sweet receptor integration of the “effective taste” and “taste” of TCM can be used for the research on the material basis of medicinal properties of “sweet” TCM.

R285

国家自然科学基金项目（81960724）