Design, synthesis, anti-inflammatory evaluation, and molecular modelling of new coumarin-based analogs combined curcumin and other heterocycles as potential TNF-α production inhibitors via upregulating Nrf2/HO-1, downregulating AKT/mTOR signalling pathways and downregulating NF-κB in LPS induced macrophages.

Persistent inflammation contributes to various inflammatory conditions. Inflammation-related diseases may be treated by inhibiting pro-inflammatory mediators and cytokines. Curcumin and coumarin derivatives can target signalling pathways and cellular factors to address immune-related and inflammatory ailments. This study involved designing and synthesising three series of coumarin-based analogs that incorporated curcumin and other heterocycles. These analogs were evaluated for their potential as anti-inflammatory agents in LPS-induced macrophages. Among the fourteen synthesised coumarin derivatives, compound 14b, which contained 3,4-dimethoxybenzylidene hydrazinyl, demonstrated the highest anti-inflammatory activity with an EC50 value of 5.32 µM. The anti-inflammatory effects of 14b were achieved by modulating signalling pathways like AKT/mTOR and Nrf2/HO-1, and downregulating NF-kß, resulting in reduced production of pro-inflammatory cytokines such as IL-6, IL-1ß, and TNF-α. The modelling studies revealed that 14b and dexamethasone bind to the same TNF-α pocket, suggesting that 14b has potential as a therapeutic agent superior to dexamethasone for TNF-α.

Three series of curcumin-based analogs, incorporating other heterocycles, were synthesised with the intention of exploring their potential as anti-inflammatory agents.Subsequently, these analogs underwent biological assessment in macrophages induced by LPS to determine their anti-inflammatory efficacy.Among the fourteen coumarin derivatives synthesised, the most potent anti-inflammatory activity was observed in the coumarin compound 14b, which featured a 3,4-dimethoxybenzylidene hydrazinyl moiety, with an EC₅₀ value of 5.32 µM.The anti-inflammatory effects of compound 14b were achieved through the modulation of signalling pathways such as AKT/mTOR and Nrf2/HO-1, as well as the downregulation of NF-kß, resulting in decreased production of pro-inflammatory cytokines including IL-6, IL-1ß, and TNF-α.Molecular modelling studies revealed that both compound 14b and dexamethasone bind to the same binding site on TNF-α, suggesting that 14b has the potential to serve as a therapeutic agent for TNF-α and other pro-inflammatory cytokines that surpasses that of dexamethasone.