18β-Glycyrrhetinic acid suppresses allergic airway inflammation through NF-κB and Nrf2/HO-1 signaling pathways in asthma mice

Abstract

Abstract18β-Glycyrrhetinic acid (18β-GA), the main bioactive component of Glycyrrhizae Radix, is considered a promising anti-inflammatory and antioxidant agent. Here, we evaluated the anti-inflammatory and antioxidant effects of 18β-GA in an ovalbumin (OVA)-induced asthma mouse model, and examined the role of NF-κB and Nrf2/HO-1 signaling pathways. The histopathological changes of lung tissue in mouse were assessed by histochemical staining and counting of inflammatory cells. The levels of IgE and inflammatory cytokines in the bronchoalveolar lavage fluid of mice were detected by ELISA. In OVA-induced asthmatic mice, 18β-GA treatment can significantly improve lung function and reduce lung inflammation including infiltration of inflammatory cells. In addition, 18β-GA reduced the OVA-induced NF-κB phosphorylation in lungs of mice while increasing the expression of Nrf2 and HO-1. These results indicate that 18β-GA protects OVA-induced allergic inflammation of airway by inhibiting phosphorylation of NF-κB and enhancing the Nrf2/HO-1 pathway, and serves as a potential treatment option for allergic inflammation of airway.

Protective Effects of Herba Houttuyniae Aqueous Extract against OVA-Induced Airway Hyperresponsiveness and Inflammation in Asthmatic Mice

“…Natural products exhibit the complex chemical backbone and the rich functionalization, making them unique biological activity and unique properties that cannot be replaced as lead compounds in pharmaceutical research [34][35][36][37]. Many antiasthmatic drugs derived from the herbal medicine, such as ephedrine and glycyrrhizic acid, have been used widely in the clinic for prevention and treatment of airway infammation and asthma [38][39][40][41]. Given the diversity of the compounds in the plant extract, network pharmacology technology was employed to fnd the potential active compounds in HHAE which may be responsible for its therapeutic efects against OVA-induced asthma.…”

Potential roles of gut microbes in biotransformation of natural products: An overview

“…Eubacterium L-8 hydrolyzed terpenoid glycyrrhizin (GL) to 18β-glycyrrhetinic acid (18β-GA; Kim et al, 2000 ). 18β-GA prevents OVA-induced airway allergic inflammation by inhibiting NF-κB phosphorylation and enhancing the Nrf2/HO-1 pathway ( Liu et al, 2022 ). These metabolic transformations provide more information about the diverse array of benefits that humans derive from Eubacterium spp.…”

Potential cellular endocrinology mechanisms underlying the effects of Chinese herbal medicine therapy on asthma

“…MMP-9 also exacerbates airway inflammation because it induces an increase in inflammatory cytokines and chemokines ( 152 ). The Nrf-2/HO-1 pathway is also closely related to inflammation, oxidative stress, and apoptosis in asthma ( 153 , 154 ). Cohosh extract (CRE) contains five kinds of traditional Chinese medicine monomers: caffeic acid, ferulic acid, isoferulic acid, cimicioic acid B, and cohosh acid F. CRE inhibits MMP-9 expression, activates the Nrf2/HO-1/NQO1 signal pathway, inhibits NF-κB phosphorylation, reduces the recruitment of inflammatory cells in peribronchial and perivascular lesions, reduces airway mucus secretion, inhibits eosinophil proliferation and airway hyperresponsiveness, and significantly weakens oxidative stress in asthma ( 155 , 156 ).…”