Exploring the anti‑inflammatory effects of Nigella sativa on cyclooxygenase‑2 through the nuclear factor‑kappa B pathway in an Aspergillus niger‑induced otitis externa mouse model

Abstract

Inflammatory condition of the external ear canal is called otitis externa (OE). This condition is often associated with microbial infections such as Aspergillus niger. This research aims to assess the anti‑inflammatory activities of the Nigella sativa (NS) extract in an A. niger‑induced OE mouse model. Mice with A. niger‑induced OE were treated with NS, and the cyclooxygenase‑2 (COX‑2), p50, and p65 protein expression were evaluated using Western blot analysis and gene expression assays, respectively. Histological examination was performed to assess the infiltration of inflammatory cells in the external ear canal tissues. Administration of NS extract significantly reduced the expression levels of COX‑2, as well as the subunits p50 and p65 genes, in a dose‑dependent manner. Histological analysis revealed a notable reduction of inflammatory cell infiltration in NS extract‑treated mice, with higher doses yielding greater reductions. NS extract effectively suppresses the expression of key pro‑inflammatory cytokines and genes, indicating its therapeutic potential in managing inflammatory conditions of the external ear canal.