Upregulation of adhesion complex proteins and fibronectin by human keratinocytes treated with an aqueous extract from the leaves of Chromolaena odorata (Eupolin)

The fresh leaves and extract of the plant Chromolaena odorata are a traditional herbal treatment in developing countries for burns, soft tissue wounds and skin infections. We have previously shown that the extract had an effect on the growth and proliferation of keratinocytes and fibroblasts in culture. This study has demonstrated that Eupolin extract increased expression of several components of the adhesion complex and fibronectin by human keratinocytes. Using indirect immunofluorescence we found increased expression (dose-dependent) of laminin 5, laminin 1, collagen IV, and fibronectin. The expression of the beta1 and beta4 integrins was upregulated by the extract at low concentrations (0.1 and 1 mug/ml), but the expression was decreased at higher doses of Eupolin (10 mug-150 mug/ml). A number of clinical studies carried out by Vietnamese and international medical investigators have demonstrated the efficacy of this extract on the wound healing process. In this study we have shown that Eupolin stimulated the expression of many proteins of the adhesion complex and fibronectin by human keratinocytes. The adhesion complex proteins are essential to stabilise epithelium and this effect could contribute to the clinical efficacy of Eupolin in healing.