Effect of diethylcarbamazine citrate and omega-3 fatty acids on trimellitic anhydride-induced rat skin allergy.

Abstract

Diethylcarbamazine citrate (DEC) is the drug most widely used in the treatment of lymphatic filariasis. Omega-3 fatty acids (ω-3 FAs) are essential polyunsaturated fatty acids and commonly found in marine oils. Both have been applied in treatment of inflammatory diseases but anti-allergic effects should be investigated. The present study was performed to test the effect of both DEC and ω -3 FAs on Trimellitic anhydride (TMA) - induced rat skin allergy. In vivo experiment was executed in white albino rats using 100 and 600 mg/ Kg body weight of DEC and ω-3 FAs, respectively in treatment. Ear thickness of sensitized rats to TMA was monitored after challenge. Blood eosinophilia was determined using differential leukocyte count while the appearance of mast cells, eosinophils and collagen fibers in skin tissue were investigated using specific stains. Colorimetric assay of NO was performed in homogenized ears, while expression of inducible nitric oxide synthase (iNOS) was detected using immunohistochemistry. Ear thickness showed a significant (p < 0.05) reduction in both of DEC and ω-3 FAs treated groups. Blood eosinophilia and skin eosinophils were significantly (p < 0.001) decreased by DEC and ?-3 FAs, while the decrease of skin mast cells was only significant (p < 0.01) when ω-3 FAs applied. The expression of iNOS and intensity of stained collagen fibers were decreased obviously by ω-3 FAs but less by DEC treatment. Histopathological observations were more normal in ω-3 FAs than DEC treated groups. ω-3 FAs was more potent antiallergic substance against TMA-induced dermatitis than DEC.