[Effects of iris xanthin on airway inflammation, airway remodeling, and the HMGB1/TLR4/NF-κB pathway in asthmatic young mice].

OBJECTIVES

To explore the effects of iris xanthin on airway inflammation, airway remodeling, and the high mobility group box 1 protein (HMGB1)/Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway in asthmatic young mice.

METHODS

Sixty male BALB/c young mice were randomly assigned into six groups: a blank group, a model group, a dexamethasone group, and low, medium, and high dose groups of iris xanthin, with ten mice per group. Asthma models were induced through intraperitoneal injections of a sensitizing agent [ovalbumin (OVA) 20 μg + aluminum hydroxide gel 2 mg], followed by 4% OVA aerosol inhalation. Lung function was measured using a pulmonary function tester to determine lung volume (LV), resting ventilation per minute (VE), and airway reactivity (Penh value). Hematoxylin-eosin (HE) staining was employed to examine and analyze airway remodeling. The contents of interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α) in bronchoalveolar lavage fluid were quantified using ELISA. Real-time fluorescence quantitative polymerase chain reaction and Western blot analysis were used to assess the expression of HMGB1/TLR4/NF-κB pathway-related mRNA and proteins in lung tissues.

RESULTS

Compared to the model group, the dexamethasone and iris xanthin-treated groups (low, medium, and high doses) exhibited significant increases in LV and VE (<0.05), with incremental dose-dependent increases observed in the iris xanthin groups. Additionally, Penh values, IL-1β, IL-6, TNF-α, and airway remodeling indicators, along with mRNA levels of HMGB1, TLR4, and NF-κB p65 and protein levels of HMGB1, TLR4, and p-NF-κB p65, were all reduced (<0.05) in a dose-dependent manner. When compared to the dexamethasone group, the low and medium dose iris xanthin groups showed decreases in LV and VE (<0.05), whereas Penh values, IL-1β, IL-6, TNF-α, and airway remodeling indicators, along with mRNA levels of HMGB1, TLR4, NF-κB p65 and protein levels of HMGB1, TLR4, and p-NF-κB p65, were increased (<0.05). No significant differences were noted in these indices between the high dose iris xanthin group and the dexamethasone group (>0.05).

CONCLUSIONS

Iris xanthin can effectively alleviates airway inflammation and inhibits airway remodeling in asthmatic young mice, possibly through the suppression of the HMGB1/TLR4/NF-κB pathway.