Protective effects of Coagulansin-A against LPS-induced inflammatory and oxidative stress responses in human lung...

Withania coagulans (Stocks) Dunal has traditionally been used to treat respiratory and inflammatory conditions in Ayurvedic and Unani therapy. However, the whole fruit extract exhibits anti-inflammatory potential against pulmonary inflammation and fibrosis. Still, the specific contribution of its primary withanolides, such as Coagulansin-A (Coag-A), remains poorly understood. Therefore, this study was designed to examine the anti-inflammatory mechanisms of Coag-A against lipopolysaccharide (LPS)-induced responses in human lung epithelial (A549) cells. Following LPS stimulation, Coag-A was administered to A549 cells, and proinflammatory cytokines and nitric oxide production were measured by ELISA and the Griess assay, respectively. Additionally, to assess reactive oxygen species production, H₂DCFDA staining was used. Furthermore, the expression of inflammatory and antioxidant signaling markers was examined by using RT-qPCR and Western blotting. In addition to this, Coag-A's binding association with nitric oxide synthase was assessed using in silico molecular docking analysis. Results indicated that Coag-A (1-100 μM) decreased the production of proinflammatory cytokines (TNF-α, IL-6, and IL-1β) and NO in a dose-dependent manner. Coag-A decreased oxidative stress and was associated with increased Nrf2 expression and reduced NF-κB expression in LPS-stimulated A549 cells. Our findings demonstrate the potential toxicological relevance of Coag-A, isolated from Withania coagulans as a bioactive natural compound capable of mitigating inflammation-associated oxidative stress.