Aerosol Delivery Enhances Percutaneous Permeability of Epidermal Growth Factor and Thioredoxin

To evaluate the effect of a nano-spray instrument, we examined the transcutaneous permeability of human recombinant thioredoxin (rhTRX) and human recombinant epidermal growth factor (rhEGF). Distribution of rhTRX and rhEGF in skin tissues was studied by immunohistochemical analyses after their application. At least 1 μg/ml rhEGF was distributed in the epidermis after application using the nano-spray instrument. Permeability of rhEGF decreased if the spraying time was shorter or the spraying distance was longer. Sprayed rhTRX was distributed more densely in the epidermis, and could strongly suppressed irritant contact dermatitis induced by croton oil, compared with the painted rhTRX group. These data suggest that aerosol delivery is a safe and effective method of enhancement of drug permeation into skin, and could be used to improve the effects of drugs.