Malvidin From Malva sylvestris L. Ameliorates Allergic Responses in Ovalbumin-Induced Allergic Rhinitis Mouse Model via the STAT6/GATA3 Pathway.

Background: Malva sylvestris L. (commonly known as mallow) has been widely used in traditional Tibetan formulations to treat allergic rhinitis (AR), and malvidin is a key anti-inflammation constituent of this plant.

Objective: The present study aimed to evaluate the potential therapeutic effect and mechanism of malvidin in an AR mouse model.

Methods: Malvidin's efficacy was evaluated in an AR mouse model induced by ovalbumin (OVA) sensitization and challenge. The factors, such as nasal symptoms, serum OVA-specific immunoglobulin E (IgE) levels, histological changes in the nasal mucosa, and expressions of Th1, Th2, Th17, and Tregs and their cytokines, were assessed. Western blotting was used to analyze the effect of malvidin on signal transducer and activator of transcription 6 (STAT6) and GATA3 expression levels.

Results: Malvidin reduced the allergic symptoms and serum levels of OVA-specific IgE in the AR model. Histological analysis indicated that malvidin alleviates nasal mucosal edema, eosinophil infiltration, and goblet cell proliferation. In addition, it altered the expression of Th1/Th2/Th17-related cytokines, enhanced the Treg population, and reduced Th2-mediated immunity by suppressing the phosphorylation of STAT6 and expression of the GATA3 protein.

Conclusions: Malvidin significantly improved allergic symptoms in an OVA-induced AR mouse model by modulating Th1/Th2 immune responses and suppressing the STAT6/GATA3 pathway, indicating its potential as a naturally sourced agent for AR management.