Tsumura Kampo Research Laboratories, Kampo Research & Development Division, Tsumura & Co., Ibaraki 3001192, Japan.
Botanical Raw Materials Research Laboratories, Botanical Raw Materials Division, Tsumura & Co., Ibaraki 3001192, Japan.
Molecules. 2020 Sep 18;25(18):4283. doi: 10.3390/molecules25184283.
The Japanese traditional medicine maobushisaishinto (MBST) has been prescribed for treating upper respiratory tract infections, such as a common cold. However, its mode of action is poorly understood, especially concerning the MBST constituent Asiasari Radix (AR). In this study, we focused on AR, with an objective of clarifying its bioavailable active ingredients and role within MBST by performing pharmacokinetic and pharmacological studies. Firstly, we performed qualitative non-targeted analysis utilizing high-resolution mass spectrometry to explore the bioavailable ingredients of AR as well as quantitative targeted analysis to reveal plasma concentrations following oral administration of MBST in rats. Secondly, we performed in vitro pharmacological study of bioavailable AR ingredients in addition to other ingredients of MBST to confirm any agonistic activities against transient receptor potential (TRP) channels. As a result, methyl kakuol and other compounds derived from AR were detected in the rat plasma and showed agonistic activity against TRPA1. This study suggests that methyl kakuol as well as other compounds have the potential to be an active ingredient in AR and thus presumably would contribute in part to the effects exerted by MBST.
日本传统药物麻黄附子细辛汤（MBST）已被用于治疗上呼吸道感染，如普通感冒。然而，其作用机制尚不清楚，特别是关于 MBST 成分细辛（AR）。在这项研究中，我们专注于 AR，通过进行药代动力学和药理学研究，旨在阐明其在 MBST 中的生物利用活性成分及其作用。首先，我们利用高分辨率质谱进行定性非靶向分析，以探索 AR 的生物利用成分，以及定量靶向分析以揭示大鼠口服 MBST 后的血浆浓度。其次，我们对 AR 的生物利用成分以及 MBST 的其他成分进行了体外药理学研究，以确认它们对瞬时受体电位（TRP）通道的激动活性。结果，在大鼠血浆中检测到甲基乌头醇和 AR 的其他化合物，并显示对 TRPA1 的激动活性。这项研究表明，甲基乌头醇和其他化合物有可能成为 AR 的活性成分，因此可能部分有助于 MBST 的作用。
