Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China.
Rapid Commun Mass Spectrom. 2013 Jun 30;27(12):1385-92. doi: 10.1002/rcm.6585.
Andrographolide (AP) is a major active anti-inflammatory compound extracted from Andrographis paniculata Nees. The metabolism stability of AP is one of the key factors for its further development as a new drug candidate. In order to clarify the biotransformation of AP among species, a comparative investigation of its in vitro metabolic pathways in human, dog and rat liver microsomes was carried out.
In the present study, the in vitro metabolic profiles of AP using pooled human (HLMs), dog (DLMs) and rat (RLMs) liver microsomes were studied. The in vitro biotransformation including phase I and phase II incubation systems and metabolic stabilities of AP were studied for the first time. Ultra-performance liquid chromatography (UPLC) coupled with Fourier transform ion cyclotron resonance (FTICR) and tandem mass spectrometry (MS/MS) was used for identification of metabolites and quantification of AP.
Eight phase I and five phase II metabolites resulted from dehydration, deoxygenation, hydrogenation and glucuronidation were tentatively identified by accurate mass measurement and MS/MS fragmentation behavior. A dehydration reaction was detected in all these incubation systems. Deoxy-AP and the related glucuronide metabolites were observed in HLMs only. Besides, the metabolic stabilities of AP in the three liver microsomes showed that the in vitro intrinsic clearance (CLint) of RLMs was much higher than that of HLMs and DLMs.
A qualitative and semi-quantitative method was developed for the identification and metabolic stabilities of AP. The general metabolic profiles between three species were clarified. Significant species differences indicated a more cautious strategy for further pharmacokinetics research of AP in animal models.
穿心莲内酯（AP）是从穿心莲中提取的主要活性抗炎化合物。AP 的代谢稳定性是其作为新药候选物进一步发展的关键因素之一。为了阐明AP 在物种间的生物转化，本文对人、犬和大鼠肝微粒体中AP 的体外代谢途径进行了比较研究。
本研究采用人（HLMs）、犬（DLMs）和大鼠（RLMs）肝微粒体，对 AP 的体外代谢谱进行了研究。首次研究了 AP 的体外生物转化，包括Ⅰ相和Ⅱ相孵育系统以及 AP 的代谢稳定性。采用超高效液相色谱（UPLC）与傅里叶变换离子回旋共振（FTICR）和串联质谱（MS/MS）联用，对代谢物进行鉴定和定量。
通过精确质量测量和 MS/MS 碎片行为，初步鉴定了 8 种Ⅰ相代谢物和 5 种Ⅱ相代谢物，包括脱水、脱氧、加氢和葡萄糖醛酸化。在所有孵育系统中均检测到脱水反应。仅在 HLMs 中观察到脱氧-AP 和相关的葡萄糖醛酸代谢物。此外，AP 在三种肝微粒体中的代谢稳定性表明，RLMs 的体外内在清除率（CLint）远高于 HLMs 和 DLMs。
建立了一种定性和半定量方法，用于鉴定和研究 AP 的代谢稳定性。阐明了三种物种之间的一般代谢谱。明显的物种差异表明，在动物模型中进一步研究 AP 的药代动力学需要更加谨慎的策略。
