Anti-inflammatory effects of Napoleona imperialis P. Beauv. (Lecythidaceae) on rat model of inflammation

Background: Methanolic extract of Napoleona imperialis, was evaluated for anti-inflammatory effect. Method: Inflammogens used were carrageenan, histamine and formaldehyde. Napoleona imperialis (200-600mg/kg) was administered orally 30 minutes before the induction of inflammation. Diclofenac (10-100mg/kg) and chlorpheniramine (10-100 mg/kg) was administered intraperitoneally. Results: Extract and Diclofenac significantly (F4, 12=15.55, P<0.01; F4, 12=13.76 P<0.01, respectively) inhibited inflammation induced with carrageenan, with extract's maximal inhibitory effect of 64% at dose 400 mg/kg. Diclofenac showed maximal inhibitory effect of 67% at dose 30 mg/kg. Extract and chlorpheniramine significantly (F4, 12=22.14, P<0.01; F4, 12=16.81, P<0.001, respectively) reduced histamine-induced edema with extract having maximal inhibitory effect of 73% at 200 mg/kg. Chlorpheniramine also had maximal inhibitory effect of 70% at 10 mg/kg. Extract and diclofenac significantly (F3, 16=11.06 P<0.001; F3, 16=22.4 P<0.0001, respectively) reduced acute phase of the formaldehyde-induced arthritis. Extract produced maximal effect of 67% at 200 and 400 mg/kg. Diclofenac had a maximal effect of 85% at 100 mg/kg. The chronic phase was ameliorated by extract and diclofenac significantly (F3, 16=11.18 P<0.001; F3, 16=18.07 P<0.0001, respectively). Extract and diclofenac also significantly (F3, 24=19.38 P<0.0001; F3, 24=59.89 P<0.0001, respectively) minimized progression of inflammation from acute to chronic phase. Extract produced a maximal effect of 83% at 400 mg/kg at chronic phase. Diclofenac also had maximal effect of 98% at 30 and 100 mg/kg. Extract and diclofenac, significantly (F4, 12=5.09 P<0.05; F4, 12=31.98 P