Qufeng Zhijing Capsule attenuates airway inflammation in experimental asthma and is associated with c-Myc/YTHDF1/TRPV1-related signaling

Abstract

Background Qufeng Zhijing Capsule (QFZJ) is a traditional Chinese medicine formulation used for asthma-related respiratory symptoms, but its effects on airway epithelial inflammation and the underlying molecular mechanisms remain unclear. Methods OVA-induced asthmatic rats received QFZJ at 0.5, 1.0, or 2.0 g/kg/day. BEAS-2B cells were pretreated with QFZJ-containing serum before LPS stimulation. Airway inflammation, cell viability, apoptosis, intracellular Ca 2+ responses, molecular expression, c-Myc enrichment at the YTHDF1 promoter, and TRPV1 mRNA m6A enrichment were evaluated. Results Medium-dose QFZJ produced the most consistent improvement in lung pathology and reduced inflammatory cytokines and epithelial alarmins in OVA-challenged rats. QFZJ also decreased the expression of c-Myc, YTHDF1, TRPV1, c-Fos, and c-Jun. In LPS-stimulated BEAS-2B cells, QFZJ-containing serum improved cell viability, reduced apoptosis and inflammatory mediator release, and attenuated intracellular Ca 2+ responses. Overexpression of c-Myc or TRPV1 partially diminished these effects. ChIP-qPCR showed enrichment of c-Myc at a predicted region of the YTHDF1 promoter, whereas m6A-RIP-qPCR showed that QFZJ reduced LPS-induced m6A enrichment of TRPV1 mRNA. Conclusion These findings support the involvement of c-Myc/YTHDF1/TRPV1-related signaling in the protective effects of QFZJ against airway epithelial inflammation. However, further loss-of-function and direct molecular interaction studies are required to establish the causal and hierarchical relationships within this pathway.