Anti-inflammatory effect of Antirrhinum majus extract in lipopolysaccharide-stimulated RAW 264.7 macrophages

Antirrhinum majus (AM) has attracted attention as a rich source of phytochemicals, which are beneficial for human health. However, the anti-inflammatory effects of AM have not been studied scientifically. Therefore, we investigated the antioxidative properties and anti-inflammatory effects of AM extract (AME) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. AME showed high radical-scavenging ability. Viability of RAW 264.7 cells was not significantly altered by AME at the concentrations of 0-300 µg/ml. LPS-induced nitric oxide (NO) production was decreased by treatment with 0-300 µg/ml AME in a concentration-dependent manner. AME pretreatment significantly inhibited the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a concentration-dependent manner. AME also considerably inhibited the mRNA and protein expression of inflammatory cytokines, such as tumor necrosis factor-a (TNF-α), interleukin-1 β (IL-1β), and interleukin-6 (IL-6). These findings provide a foundation for further studies and use of AM in nutraceuticals.

Keywords: Antirrhinum majus; antioxidative; anti‐inflammatory; cytokines; ethanol extract.