Anti-inflammatory effects of a Houttuynia cordata supercritical extract.

Anti-inflammatory effects of Houttuynia cordata supercritical extract (HSE) were investigated in a carrageenan-air pouch model. HSE (200 mg/kg, oral) suppressed exudation and albumin leakage, as well as inflammatory cell infiltration. Dexamethasone (2 mg/kg, i.p.) only decreased exudation and cell infiltration, while indomethacin (2 mg/kg, i.p.) reduced exudate volume and albumin content. HSE lowered tumor-necrosis factor (TNF)-alpha and nitric oxide (NO), as well as prostaglandin E(2) (PGE(2)). Dexamethasone only reduced TNF-alpha and NO, while indomethacin decreased TNF-alpha and PGE(2). The suppressive activity of HSE on NO and PGE(2) production was confirmed in RAW 264.7. These results demonstrate that HSE exerts anti-inflammatory effects by inhibiting both TNF-alpha-NO and cyclooxygenase II-PGE(2) pathways.