Anti-inflammatory activities of constituents isolated from Phyllanthus polyphyllus

Four compounds, including one benzenoid, 4-O-methylgallic acid (1), together with three arylnaphthalide lignans, namely phyllamyricin C (2), justicidin B (3) and diphyllin (4) were isolated from the whole plants of Phyllanthus polyphyllus L. (Euphorbiaceae). This was the first isolation report of compounds 1–4 from this plant species. The in vitro inhibitory effects of these compounds were evaluated on the production of nitric oxide (NO) and cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-12), from LPS/IFN-γ activated murine peritoneal macrophages. The results indicated that the 50% inhibition concentration (IC50) values of NO production from activated peritoneal macrophages by compounds 1–4 were 100, 25, 12.5 and 50 μM, respectively. In parallel, these dilutions were approximately inhibited in a similar manner to that observed for cytokines (TNF-α, and IL-12) production. On the other hand, at 100 μM concentration compounds 3 and 4 showed 50% inhibition of NO production from peritoneal macrophages that had been pre-activated with LPS/IFN-γ for 24 h, whereas compounds 1 and 2 inhibited only about 20 and 10%, respectively. These results support the use of this plant for the treatment of inflammatory diseases in oriental traditional medicine.