Inhibitory effect of topical Adelmidrol on antigen-induced skin wheal and mast cell behavior in a canine model of allergic dermatitis

BACKGROUND: Adelmidrol is a semisynthetic derivative of azelaic acid and analogue of the anti-inflammatory compound palmitoylethanolamide (PEA). Based upon its physicochemical properties, adelmidrol is suitable for topical application. The main objective of the present study was to evaluate the efficacy of a topical adelmidrol emulsion on early and late inflammatory responses in hypersensitive dogs. Repeated intradermal injections of Ascaris suum extract were performed in both lateral thoracic areas of six conscious hypersensitive Beagle dogs, topically treated during 8 consecutive days. Adelmidrol (2%) was applied to one side and vehicle to the other. 24 hours after the last antigen challenge, two biopsies (adelmidrol- and vehicle-treated side) were obtained for each dog at the antigen injection site. RESULTS: A significant reduction in the antigen-induced wheal areas was observed on the 4(th) and 7(th) day of adelmidrol treatment. Moreover, cutaneous mast cell numbers were significantly decreased in biopsies obtained after 8 consecutive days of topical adelmidrol treatment. CONCLUSIONS: The results obtained in the present study show that topical treatment with adelmidrol might represent a new therapeutic tool in controlling the early and late allergic inflammatory skin responses in companion animals.