SYNTHETIC CURCUMIN INHIBITS CARRAGEENAN-INDUCED PAW EDEMA IN RATS

Curcumin is the main active ingredient in Curcuma longa L. (Turmeric) and exhibits potent antioxidative and anti-inflammatory activities. In this study, the anti-inflammatory activity of curcumin was evaluated in a carrageenan-induced rat paw edema test and compared with that of indomethacin. Rats treated with indomethacin (10 mg/kg, p.o.) and curcumin (25, 50, 100, 200 and 400 mg/kg, p.o.) showed a significant reduction in carrageenan-induced paw edema (p<0.05). Indomethacin inhibited edema by 46.87% and 65.71% at 2 and 3 h after carrageenan injection, respectively. The inhibitory effect of curcumin began at 2 h or later after carrageenan injection depending upon the administered dose. Low doses of curcumin (25-100 mg/kg) gave significant inhibitory effects of 30.43-34.88%, and higher doses caused significant inhibition at levels of 32.61-58.97%. The reduction of edema by indomethacin and curcumin at 2 h or more after carrageenan injection suggests that both compounds produce anti-inflammatory effects in the second phase of edema, indicating inhibition of prostaglandin synthesis.