Simultaneous quantification of arctigenin and its glucuronide conjugate in mouse plasma using ultra-high performance liquid chromatography coupled to tandem mass spectrometry.

Arctigenin is a natural lignin and a main active component of Fructus arctii, the dried fruit of Arctium lappa. This compound was reported to have some biological activities such as anti-inflammatory, antioxidant, antiviral, renoprotective, and antitumor effects. Arctigenin is mainly metabolized to arctigenin-4'-O-glucuronide by UDP-glucuronosyltransferase. In this study, a simultaneous quantification method was established and validated for measuring arctigenin and arctigenin-4'-O-glucuronide in mouse plasma using ultra-high performance liquid chromatography with tandem mass spectrometry. The assay fulfilled the requirements of the United States Food and Drug Administration guideline for assay validation, with a lower limit of quantification of 2.00 ng/mL for arctigenin and 50.0 ng/mL for arctigenin-4'-O-glucuronide. The recovery rate and matrix effect ranged from 78.4 to 102.8% and 92.5 to 106.3%, respectively, for arctigenin, and 74.3 to 109.2% and 94.9 to 110.2% for arctigenin-4'-O-glucuronide. The method was applied to the measurement of plasma concentrations of arctigenin and arctigenin-4'-O-glucuronide in the plasma of mice after administration of arctigenin. All measured concentrations were within the calibration ranges. Our novel method may be useful to measure plasma arctigenin and arctigenin-4'-O-glucuronide concentrations, and contribute to evaluate the pharmacokinetics of arctigenin and arctigenin-4'-O-glucuronide in mice.