Immuno-Modulatory, Anti-Psoriatic Effects and Furanochromone (Khellin and Visnagin) Contents of Ammi Visnaga (L.) Hydeoethanolic Extract

Abstract

Objectives: Psoriasis is a chronic skin inflammation disease, which is requires prolonged treatment, thereby interfering with the side effects of synthetic drugs. Traditional herbal medicine, and recent plant-based drugs, have been proven beneficial in reducing these side effects of synthetic drugs. Ammi visnaga L. species contains 2 furanochromones (khelline and visnagine) with a similar structure than psoralens that possess antipsoriatic activity. The objective of the present study was to verify the influence of extraction solvent on these two furanochromone content of Ammi visnaga and to study its immunomodulatory and antipsoriatic effect in vivo. Materials and Methods: In the present study, khellin and visnagin contents were compared between aqueous, hydroethanolic and ethyl acetate extracts of Ammi visnaga L. by highperformance liquid chromatography (HPLC), and their immunomodulating and antipsoriatic effects were studied for the hydroethanolic extract, in vivo, by hemagglutination test after immunization using human erythrocytes and by Psoriasis-like dermatitis induced using ultraviolet-C (UV-C) irradiations of two hours, during 3 successive days or by application of 2 a formaldehyde and Complete Freund adjuvant (CFA) mixture (1:10 ratio) during 3 successive days. Results: Ethanol at 60% showed the best results in the extraction of furanochromones (khellin and visnagin), followed by ethyl acetate and then by water. This hydroethanolic extract at 100 mg/kg showed an immunostimulating effect of the humoral response, by increasing the value of the hemagglutination antibody (HA) titer. The same extract, at a dose of 300 - 600 mg/kg orally or 2-4% topically, has a considerable antipsoriatic effect, reducing the psoriatic severity score (erythema and squaling), the epidermal thickness and the leukocytic infiltration. Conclusion: the 60% hydroethanol extract is better in the extraction of furanochromones from Ammi visnaga. This extract has considerable immunostimulant and antipsoriatic effects.