Abstract
Licorice is a crude drug that is used in traditional Japanese Kampo medicine and is also used as a sweetener. Occasionally, it causes pseudoaldosteronism (PsA) as a side effect. The major symptoms include hypokalemia, hypertension, edema, and low plasma aldosterone levels. PsA might be caused by the metabolites of glycyrrhizinic acid (GL), a component of licorice. The development of PsA markedly varies among individuals; however, the factors that cause these individual differences remain unknown. In this study, 78 patients who consumed Kampo medicines containing licorice were enrolled, and their laboratory data, including serum potassium levels, plasma aldosterone concentrations (PAC), and the concentrations of GL metabolites in the residual blood and/or urine samples were evaluated. Of the 78 participants, 18β-glycyrrhetinic acid (GA), 3-epi-GA, 3-oxo-GA, 18β-glycyrrhetinyl-30-O-glucuronide (GA30G), and 3-epi-GA30G were detected in the serum samples of 65, 47, 63, 62, and 3 participants, respectively. Of the 29 urine samples collected, GA30G and 3-epi-GA30G were detected in 27 and 19 samples. 3-epi-GA30G is a newly found GL metabolite. Moreover, 3-epi-GA, 3-oxo-GA, and 3-epi-GA30G were identified in human samples for the first time. High individual differences were found in the appearances of 3-epi-GA in serum and 3-epi-GA30G in urine, and the concentrations of these metabolites were correlated with serum PsA markers. The inhibitory titers of 3-epi-GA, 3-oxo-GA, GA30G, and 3-epi-GA30G on human 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) were almost similar. These findings suggest that 3-epi-GA and/or 3-epi-GA30G are associated with individual differences in the development of PsA. Significance Statement In this study, we detected 3-epi-GA in human serum for the first time. We also identified 3-epi-GA30G as a novel GL metabolite in human urine. These GL metabolite levels showed correlations with markers of PsA. Additionally, there are individual differences in whether or not they appear in the serum/urine. In conclusion, 3-epi-GA/3-epi-GA30G correlates with individual differences in the development of PsA.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Drug metabolism and disposition: the biological fate of chemicals
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
