Penicilazaphilone C alleviates allergic airway inflammation and improves the immune microenvironment by hindering the NLRP3 inflammasome

Penicilazaphilone C (PAC) is hypothesized to potentially serve as a therapeutic treatment for allergic airway inflammation by inhibiting the NLRP3 inflammasome and reducing oxidative stress. An allergic asthma model was induced in female BALB/c mice of the OVA, OVA+PAC, OVA+PAC+LPS, and OVA+Dex groups by sensitizing and subsequently challenging them with OVA. The OVA+PAC and Normal+PAC groups were treated with PAC, while the OVA+PAC+LPS group also received LPS. The OVA+Dex group was given dexamethasone (Dex). Samples of serum, bronchoalveolar lavage fluid (BALF), and lung tissue were collected for histological and cytological analysis. Allergic mice treated with PAC or Dex showed inhibited inflammation and mucus production in the lungs. There was a decrease in the number of inflammatory cells in the BALF, lower levels of inflammatory cytokines in the serum and BALF, and a reduction in the protein expression of NLRP3, ASC, cleaved caspase-1, IL-1β, activated gasdermin D, MPO, Ly6G, and ICAM-1. Additionally, oxidative stress was reduced, as shown by a decrease in MDA and DCF, but an increase in SOD and GSH. Treatment with PAC also resulted in a decrease in pulmonary memory CD4+ T cells and an increase in regulatory T cells. However, the positive effects seen in the PAC-treated mice were reversed when the NLRP3 inflammasome was activated by LPS, almost returning to the levels of the Sham-treated mice. PAC acts in a similar way to anti-allergic inflammation as Dex, suggesting it may be a viable therapeutic option for managing allergic asthma inflammation.