Metabolomic and Pharmacologic Insights of Aerial and Underground Parts of Glycyrrhiza uralensis Fisch. ex DC. for Maximum Utilization of Medicinal Resources

Front Pharmacol. 2021 Jun 1:12:658670. doi: 10.3389/fphar.2021.658670. eCollection 2021.

Abstract

The roots of Glycyrrhiza spp. have been utilized in Traditional Chinese medicine (TCM) for thousands of years. Non-traditional (aerial) parts constitute a large portion of the biomass of Glycyrrhiza plants and are mostly discarded after harvesting the roots and rhizomes. Through comparative phytochemical and anti-inflammatory activity analyses, this study explored the potential benefits of the aerial parts of Glycyrrhiza uralensis Fisch. ex DC. as medicinal materials. First, a combined approach based on GC/MS and UHPLC-ESI-QTof MS analysis was adopted for the identification and quantitative examination of medicinally important compounds from G. uralensis. Additionally, a bioassay-guided fractioning of ethanolic extracts of G. uralensis leaf material was performed and its anti-inflammatory activity was tested. The aerial portion of G. uralensis was rich in medicinally important compounds. Two compounds (henicosane-1 and decahydroisoquinoline-2) were found to exert a significant anti-inflammatory effect, inhibiting the release of pro-inflammatory mediators (NO and PGE2) and cytokines (IL-1β, IL6, and TNF-α), without exerting cytotoxic effects. Moreover, both compounds down-regulated iNOS and COX-2 mRNA expression. These results suggest that non-traditional parts of G. uralensis are suitable sources of bioactive metabolites that can be explored for medicinal purposes.

Keywords: henicosane; inflammation; licorice; metabolomics; pro-inflammatory cytokines.