The investigators have hypothesized that improved healing outcomes in the investigators rabbit model were due to kynurenine and by-products stimulating MMP, which in turn acted on cells (fibroblasts) to reduce collagen production. This hypothesis lead to a study investigating the effects of topical 0.5% kynurenine cream treatment on MMP-1 and MMP-3 expression in fibrotic rabbit ear wound model. The results showed marked improvement in scar formation suggesting the possible use of kynurenine as an anti-fibrogenic treatment against scarring.