# Anti-Inflammatory Effects of Novel _Glycyrrhiza_ Variety Wongam In Vivo and In Vitro
## 4 Discussion  
Licorice and its constituents have been reported to have antialergic and anti-inflammatory activities [24; 25]. Therefore, investigating WG to verify whether it has the previously reported pharmacological activities found in existing licorice varieties is as important as developing novel varieties to utilize WG. The antialergic effects of this study support the promising activities of WG. In the present study, we investigated the inhibitory effects of WG on mast-cell-mediated allergic inflammation. IgE-mediated allergic reactions through the Fc\(\epsilon\)RI receptor are known to be the main mechanism of mast cell activation and systemic anaphylaxis [26]. Thus, we evaluated whether WG inhibits mast cell degranulation using a compound-48/80-induced mouse model of anaphylaxis and histamine-releasing cells, such as rat basophilic leukemia RBL-2H3 and human mast cell line HMC-1 cells. WG treatment delayed mortality in anaphylactic events due to systemic mast cell degranulation. The administration of WG had a better effect than the positive control DSCG treatment group (Figure 1A). Moreover, we found that the release of preformed mediator histamine expression in both mast cell types was reduced by WG treatment (Figure 3). This correlates with the decrease in serum IgE levels after WG treatment in the mouse model of anaphylaxis (Figure 1B). As a mast cell stimulator, compound 48/80 causes alterations in intracellular calcium influx as well as cyclic adenosine monophosphate (cAMP) levels, consequently causing allergic reactions, including IgE synthesis, mast cell degranulation, and histamine release [27; 28]. The mast cells activated by compound 48/80 exert host defense, sensitization to antigen, and proinflammatory functions through the release of mediators such as cytokines, chemokines, leukotrienes, and tryptase proteases, as well as histamine [27; 29]. These mediators can promote Th2 cell differentiation and class switching into IgE in B cells [30]. While the serum levels of IgE in circulation are very low, elevated total IgE levels indicate that an allergic reaction is in progress. The increased level of IgE induced by compound 48/80 reflected systemic anaphylaxis, which is a form of immediate hypersensitivity. However, this systemic allergic reaction was inhibited by DSCG and WG in this study. DSCG inhibits extracellular calcium influx and degranulation of mast cells, subsequently preventing the release of histamine and mediator allergic inflammatory reactions [31]. Furthermore, our results showed that WG decreased the expression of Th2 cytokines such as IL-4 and IL-13, which are required for IgE synthesis (Figure 5B). The results were in agreement with the previous report that DSCG selectively inhibited IL-4 and spontaneous IgE production by B cells [32]. It is supposed that WG also alleviates allergic reaction induced by compound 48/80 through blocking IgE synthesis, mast cell degranulation, and histamine release via a similar preventive mechanism to DSCG. In response to allergies, a diverse range of immunologic messengers, such as calcium, induce the biosynthesis or release of proinflammatory cytokines and chemokines in mast cells [33]. The present study found that WG suppressed TNF-\(\alpha\) and IL-6 in both mast cells and anaphylaxis mouse models, suggesting that WG can regulate mast-cell-mediated allergic inflammatory responses. In line with this, WG downregulated the expression of chemokines, such asotaxin, MIP-2, and MCP-1, as well as the expression of Th2 cytokines (IL-4, IL-5, and IL-13) in PMACI-stimulated HMC-1 cells (Figure 5). These results are supported by previous reports showing that the main constituents, glycyrrhizin and licorice flavonoids, inhibit the expression levels ofotaxin, MIPs, MCP-1, TNF-\(\alpha\), and IL-6 in lipopolysaccharide-stimulated RAW264.7 cells [34] and downregulate MCP-1 and MIP-2 expression in cerulein-stimulated pancreatic acinar cells [35].