Topical application of a film-forming emulgel dressing that controls the release of stratifin and acetylsalicylic acid and improves/prevents hypertrophic scarring

Abstract

Here, we evaluate the efficacy of an emulgel dressing to control the release of an antifibrogenic factor, stratifin (SFN), along with an anti-inflammatory drug, acetylsalicylic acid (ASA), to be used as a wound dressing with hypertrophic scar reducing features. Emulgel dressings were prepared by dispersing positively charged submicron vesicles in carboxymethyl cellulose gel. Release kinetics of SFN/ASA and toxicity for primary skin cells were assessed in vitro. Antifibrogenic efficacy of medicated emulgel dressings was tested on a rabbit ear fibrotic model. Following topical application on the wounds, emulgels formed an occlusive film and controlled the release of SFN and ASA for 7 and 24 hours, respectively. Wounds treated with SFN/ASA-containing emulgel dressings showed an 80% reduction in scar elevation compared with untreated controls. Topical formulations were nontoxic for cultured human keratinocytes and fibroblasts. Inflammation was significantly controlled in treated wounds, as shown by a reduced number of infiltrated CD3(+) T cells (p < 0.001) and macrophages. SFN/ASA-treated wounds showed a significantly higher (p < 0.001) expression of matrix metalloproteinase-1, resulting in reduced collagen deposition and less scarring. Film-forming emulgel dressings that control the release of antifibrogenic and anti-inflammatory factors provide an excellent treatment option for postburn hypertrophic scar management.