Yanghe Pingchuan granules induce ferroptosis in airway smooth muscle cells to improve bronchial asthma via the METTL3/P53/SLC7A11 signaling pathway

Background

Recent studies have found that ferroptosis is strongly associated with the development of bronchial asthma (BA). However, the mechanism underlying the role of ferroptosis in asthma remains unclear. Yanghe Pingchuan granules (YPG) have significant curative effect in the clinical treatment of BA. In our previous study, we found that YPG inhibit pyroptosis in the airway smooth muscle cells (ASMCs) of and reducing airway inflammation. Whether ferroptosis participated in the YPG treated BA activity is an interesting project.

Purpose

The aim of this study was to investigate the protective effects and the related mechanisms of YPG against BA.

Methods

We used ultra high-performance liquid chromatograph (UPLC) to analyze the composition of YPG. Ovalbumin (OVA)-induced BA models were developed in vivo. YPG was administered to rats by gavage and ASMCs were isolated and cultured using α-SMA and CCK8 was used to assess cell viability. Gene editing, m⁶A RNA immunoprecipitation (MeRIP), western blotting, RT-qPCR, and transmission electron microscopy (TEM) was used to assess ferroptosis protein and mRNA expression in ASMCs. Further, the mechanism of YPG-induced regulation of ferroptosis in ASMCs via the METTL3/P53/SLC7A11 signaling axis was interrogated. BA rats were used to verify the therapeutic effects and mechanism of YPG. Moreover, hematoxylin and eosin staining was used to evaluate pathological changes using animal samples, while immunofluorescence, western blotting, RT-qPCR, and TEM were used to verify the mechanism by which YPG improved BA through the METTL3/P53/SLC7A11 signaling axis.

Results

Qualitative analysis revealed seven major components in YPG. Our in vivo and in vitro data confirm that YPG significantly induced ferroptosis in ASMCs. YPG treatment effectively increased the expression of Fe²⁺, P53, and PTGS2, while decreasing SLC7A11, GPX4, and FTH1 expression. Moreover, TEM data revealed that YPG-induced mitochondrial membrane rupture and ridge disappearance. Additionally, YPG significantly increased METTL3 expression levels and upregulated the levels of P53 m⁶A, thus promoting its degradation. Notably, overexpression of METTL3 and P53 induces ferroptosis of ASMCs BA rats.

Conclusion

We show that YPG may induce ferroptosis of ASMCs in BA rats by activating the METTL3/P53/SLC7A11 signaling pathway, thus alleviating disease symptoms.