Discovery of dibenzylbutane lignan LCA derivatives as potent anti-inflammatory agents†

Inflammation is the body's response to defence against infection or injury, and is associated with the progression of many diseases, such as inflammatory bowel disease (IBD) and rheumatoid arthritis (RA). LCA, a dibenzylbutane lignan extracted from the roots of traditional medicinal plant Litsea cubeba (Lour.) Pers., has demonstrated promising anti-inflammatory activity. In this study, a series of novel LCA derivatives were designed, synthesized, and evaluated for anti-inflammatory activity. Lipopolysaccharide (LPS)-induced RAW 264.7 cell model experiments showed that compound 10h (at 20 μM of concentration) had the strongest inhibitory effect on NO release, and inhibited the secretion and gene expression levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in vitro. In addition, western blot, immunofluorescence, and molecular docking showed that the anti-inflammatory mechanism of compound 10h may be related to the nuclear factor (NF)-κB signalling pathway. In vivo studies based on a carrageenan-induced mouse paw edema model have shown significant anti-inflammatory activity of compound 10h at 20 mg kg⁻¹. Preliminary in vitro and in vivo studies indicate that compound 10h has the potential to be developed as a novel anti-inflammatory agent.