According to Botanical Medicine, the anti-inflammatory actions of glycyrrhizin (GL) may stem from suppression of cytokines:

“As testimony to its anti-inflammatory properties, glycyrrhizin alleviated allergic asthma in an experimental mouse model, increased the IL-4 and IL-5 levels, decreased eosinophil counts and IgE levels, and upregulated total IgG2a in serum.

These results indicated that glycyrrhizin interfered with the production of IgE by decreasing the IgE-stimulating cytokines. It also attenuated lung inflammation and mucus production in mice.”