Dehydrostephanine Isolated from Stephania venosa Possesses Anti-Inflammatory Activity in Lipopolysaccharide-Activated RAW264.7 Macrophages

Stephania venosa (Blume) Spreng., is a medicinal herb wildly used as a folklore medicine in Thailand. Many studies have reported that S. venosa tuber revealed a variety of pharmacological activities including anti-malarial, anti-microbial, anti-cancer, anti-oxidant, and anti-inflammatory activities. In this study, we investigated the effects of (–)-stephanine and dehydrostephanine isolated from S. venosa tuber on anti-inflammation in lipopolysaccharide (LPS)-activated RAW264.7 macrophages. RAW264.7 cells were treated with (–)-stephanine and dehydrostephanine in the presence of LPS and cell viability was determined by MTT assay. The levels of inflammatory mediators, nitric oxide (NO) and pro-inflammatory cytokines were determined by Griess assay and enzyme-linked immunosorbent assay, respectively. Pre-treatment of dehydrostephanine significantly suppressed NO secretion in LPS-activated RAW264.7 cells with the half-maximal inhibitory concentration (IC 50 ) value of 26.81 ± 0.25 μM. However, (–)-stephanine had IC 50 value on the inhibition of NO secretion of >40 μM. In addition, dehydrostephanine at concentrations of 20–80 μM significantly reduced LPS-induced tumor necrosis factor-alpha, interleukin-1b and interleukin-6 production in RAW264.7 cells. The present study showed that dehydrostephanine possesses the anti-inflammatory effect on LPS-activated RAW264.7 macrophages by suppression of inflammatory mediators. Dehydrostephanine may be a promising candidate compound for further investigation of a novel class of anti-inflammatory drug.