Effect of peroxybenzoic acid and hydroxybenzoic acid on allergic asthma

Peroxybenzoic acid and hydroxybenzoic acid are phenolic compounds commonly used in cosmetics and pharmaceuticals that have shown potential as anti-inflammatory agents. We compared their effects on allergic airway inflammation and Th2 cytokine responses in a murine model of ovalbumin-induced allergic asthma in Balb/c mice. Ten Balb/c mice were randomly assigned to four groups: control, asthma, asthma treated with peroxybenzoic acid, and asthma treated with hydroxybenzoic acid. Asthma was induced through intraperitoneal sensitization with ovalbumin. Then, the mice received intranasal instillations of either peroxybenzoic acid or hydroxybenzoic acid. Then, lung tissues were harvested for histological staining (H&E, PAS) to assess peribronchial and perivascular inflammatory infiltrates as well as goblet cell hyperplasia. Serum levels of IgE, IL-4, IL-5, and IL-13 were measured using ELISA. Data were analyzed using one-way ANOVA with Tukey’s post-hoc test. Mice treated with hydroxybenzoic acid (the asthma + hydroxybenzoic acid group) showed a significant reduction in both peribronchial and perivascular inflammation. The histopathological scores for this group were markedly lower than those of the untreated asthma group (p < 0.01). Additionally, this group demonstrated a significant decrease in IL-5 levels (p < 0.05), while serum concentrations of IgE, IL-4, and IL-13 remained unchanged (p > 0.05). In contrast, mice in the asthma + peroxybenzoic acid group did not show significant differences in airway inflammation or levels of the measured cytokines and IgE when compared to the untreated asthma group (p > 0.05). In this murine model, hydroxybenzoic acid selectively suppresses eosinophil-driven inflammation and IL-5 production, setting it apart from peroxybenzoic acid and many broad-spectrum anti-inflammatory compounds. These findings support the need for further preclinical and early-phase clinical studies to evaluate hydroxybenzoic acid’s potential as a targeted therapy for allergic asthma.