# Mechanisms of Aletris spicata (Thunb.) Franch. Extract in Asthma Therapy: Oxidative Stress, Inflammation, and Gut Microbiota

## TL;DR

This study explores how Aletris spicata extract helps treat asthma by reducing inflammation, oxidative stress, and restoring gut microbiota balance in mice.

## Contribution

The study identifies 33 compounds in Aletris spicata and reveals its multi-target mechanism involving Nrf2, NF-κB pathways, and gut microbiota modulation in asthma therapy.

## Key findings

- Aletris spicata reduced inflammatory cells and cytokines in bronchoalveolar lavage fluid and serum of asthmatic mice.
- The extract alleviated oxidative stress in lung tissue and inhibited NF-κB p65 nuclear translocation.
- Aletris spicata restored gut microbiota homeostasis and showed correlations between gut bacteria and inflammation markers.

## Abstract

Aletris spicata (Thunb.) Franch. (AS), belonging to the Nartheciaceae family, exhibits therapeutic efficacy against asthma. However, the underlying mechanism is still unclear. In this study, the chemical composition of AS was qualitatively identified by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS). We used an ovalbumin (OVA)-induced asthma mouse model to evaluate the therapeutic effect of AS on asthma. The effects of AS on airway inflammation, oxidative stress, and gut microbiota in asthmatic mice were examined. The results showed that 33 compounds were identified from AS. It could reduce the number of inflammatory cells in bronchoalveolar lavage fluid (BALF) and the concentrations of inflammatory cytokines in BALF and serum in asthma mice. The level of oxidative stress in the lung tissue of mice was significantly reduced, and the inflammatory response in lung tissue and intestinal tissue was weakened. Moreover, AS can reduce oxidative stress and inflammatory response partly through the modulation of Nrf2 and NF-κB signaling pathways. In addition, we found that AS could also maintain the homeostasis of gut microbiota in asthma mice. These findings provide a basis for the further investigation of the potential of AS for the treatment of asthma.

Aletris spicata (Thunb.) Franch. (AS), a traditional edible and medicinal plant for treating asthma, was investigated for its therapeutic mechanisms. Liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS) analysis identified 33 compounds in AS. In ovalbumin (OVA)-induced asthmatic mice, AS significantly reduced inflammatory cells (neutrophils, lymphocytes, eosinophils) in bronchoalveolar lavage fluid (BALF) and decreased IL-4, IL-5, IL-13, TNF-α, and serum IgE while increasing IFN-γ. AS alleviated lung and intestinal inflammation, reduced ROS and MDA levels, and enhanced SOD activity. Immunohistochemistry and Western blot revealed AS upregulated Nrf2/HO-1 expression and inhibited NF-κB p65 nuclear translocation. Gut microbiota studies demonstrated AS restored intestinal flora homeostasis by modulating the richness, diversity, and composition. Spearman correlation analysis identified significant relationships between oxidative stress markers, inflammatory cytokines, and specific gut bacteria. These findings indicate that AS mitigates asthma through antioxidant effects (Nrf2/HO-1 pathway), anti-inflammatory actions (NF-κB pathway), and gut microbiota modulation. The study provides a scientific basis for developing AS as a natural anti-asthma treatment or functional food. The multi-target mechanism involving oxidative stress, inflammation, and gut flora highlights AS’s comprehensive therapeutic potential for asthma management.