Anti-inflammatory Effect of Hydroalcoholic Extract of the Washingtonia filifera Seeds in Carrageenan-Induced Paw Edema in Rats

Background: Medicinal plants are believed to be important sources of new chemical substances with potential therapeutic effects. Washingtonia filifera is characterized by its high content of flavonoids. Numerous studies suggest that flavonoids have potential for the prevention and treatment of several diseases. Objectives: This study aimed to investigate the anti-inflammatory activity of the Washingtonia filifera seeds’ hydroalcoholic extract (WSE). Materials and Methods: The hydroalcoholic extract was administered to male Wistar rats. Carrageenan-induced paw edema was used to evaluate the anti-inflammatory activity. The WSE (100, 200, and 400 mg/kg) or vehicle were administered intraperitoneally 30 minutes before the subplantar injection of carrageenan. Intraperitoneal indomethacin (10 mg/kg) was used as standard drug. Results: The intraperitoneal WSE (100 - 400 mg/kg) produced the anti-inflammatory effect in a dose-dependent manner with a median effective dose (ED50) of 164.4 mg/kg (124.16 - 203.7 mg/kg). Furthermore, the anti-inflammatory effect of WSE was comparable to indomethacin (10 mg/kg) Conclusions: These results indicated that WSE has a potent anti-inflammatory action and confirmed that the extract contains an effective anti-inflammatory substance(s).