Prim-O-glucosylcimifugin attenuates lipopolysaccharide- induced inflammatory response in RAW 264.7 macrophages

Background: Radix Saposhnikoviae (RS) exerts anti-inflammatory, analgesic, antipyretic, antioxidation effects and has been used in traditional Chinese medicine to treat common colds, headache, and rheumatoid arthritis. Prim-O-glucosylcimifugin (POG) is the highest content chromone and one of the major active constituents in RS. Objective: The study was aimed to explore the anti-inflammation effects of POG in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Materials and Methods: Cell viability was detected by Cell Counting Kit-8 assay. Production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 was assessed by enzyme-linked immunosorbent assay. Real-time polymerase chain reaction and Western blot were performed to analyze mRNA and protein levels, respectively. Results: During the whole experiment, 15, 50, and 100 μg/mL of POG had no cytotoxicity on RAW 264.7 cells. POG dose-dependently inhibited the production of NO, TNF-α, IL-1β, and IL-6 that were induced by LPS. POG treatment downregulated the mRNA and protein expression inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2) in LPS-activated RAW 264.7 macrophages in a concentration-dependent manner. Furthermore, LPS-induced JAK2/STAT3 activation was prevented in RAW 264.7 macrophages by POG treatment. STAT3 overexpression significantly reversed the effects of POG on LPS-activated RAW 264.7 macrophages. Conclusion: These results demonstrate that POG exerts anti-inflammatory effects through the inhibition of iNOS and COX-2 expression by inhibiting the phosphorylation of JAK2/STAT3.