Dihydrofisetin is a flavanonol derived from some edible wild herbs and traditional Chinese medicines. It has been found to possess many biological activities. However, the anti-inflammatory potential of Dihydrofisetin remains uncharacterized. The aim of the present study was to investigate the anti-inflammatory activity of Dihydrofisetin and its underlying mechanisms. We found that Dihydrofisetin dose-dependently inhibited lipopolysaccharide-induced productions of nitric oxide (NO) and prostaglandin E2 (PGE2) in RAW 264.7 macrophages, probably through suppressing the protein expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). The expressions of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and monocyte chemotactic protein (MCP-1) were also suppressed. We further demonstrated that Dihydrofisetin inhibited the activation of mitogen-activated protein kinases (MAPKs) pathway and phosphorylation of IκB-α whereas upregulated the expression of heme oxygenase-1 (HO-1). The in vivo carrageenan-induced mice paw edema study also indicated that treatment with 100 mg/kg of Dihydrofisetin could significantly inhibit carrageenan induced paw edema, decrease the levels of TNF-α, IL-6 and MDA, and increase the activity of GSH-Px in paw tissues. Taken together, Dihydrofisetin may act as a natural agent for treating inflammatory diseases by targeting MAPK, NF-κB and HO-1 pathways.Graphical abstract
Dihydrofisetin is a flavanonol derived from some edible wild herbs and some traditional Chinese medicines. The results indicated that Dihydrofisetin attenuated the synthesis of NO and PGE2, suppressed the expressions of iNOS and COX-2, and inhibited the production of TNF-α, IL-1β, IL-6, MCP-1 in LPS-stimulated RAW 264.7 cells. In conclusion, Dihydrofisetin may act as a natural agent for treating inflammatory diseases by targeting MAPK, NF-κB and HO-1 pathways. The in vivo animal study also indicated that Dihydrofisetin with strong antioxidant and anti-inflammatory properties.