We investigated the in vivo effect of curcumin nanoparticles (nC) in addition to diclofenac sodium on local edema and oxidative stress parameters in carrageenan-induced paw edema on rats. Seven groups were investigated: control group (C), the acute inflammation (AI) group, an AI group treated with Diclofenac (AID, 5 mg/kg b.w. Diclofenac sodium), two AI groups treated with cC (conventional Curcumin)-AIC200 and AIcC200D (D = Diclofenac, 200 represent the concentration of active substance expressed in mg/kg b.w.), and two AI groups with nC (Curcumin nanoparticles)-AIC200 and AIcC200D. Serum and tissue oxidative stress was assessed by measuring five parameters. Curcumin nanoparticles alone and in combination with D better reduced the paw edema than D alone (p < 0.027). The rats treated with D and nC (AIcC200D) had the highest inhibition percentage on edema, reaching the maximum level of inhibition (81%) after 24 h. Conventional curcumin and nC presented antioxidant effects in acute inflammation, with significantly better results obtained for nC. The pro-oxidant markers were reduced up to 0.3 by the cC and up to 0.4 times by the nC and both solutions increased the antioxidant markers up to 0.3 times. The nC enhanced the antioxidative efficacy of D, as this combination reduced the pro-oxidant markers up to 1.3 times. Curcumin nanoparticles could represent a therapeutic option in association with classical nonsteroidal anti-inflammatory medication in acute inflammation, as they might offer a reduction of drug dose and possible limitation of their associated side effects.
Keywords: carrageenan; curcumin; diclofenac sodium; nanoparticles; paw edema.