An ethanol extract from Alstonia scholaris is a potent irritation inhibitor in human skins

Abstract

Alstonia scholaris is a plant, known for having bitter tonic and astringent properties in India and the Philippines; it is particularly useful for chronic diarrhea and dysentery [1]. These potentials allow us to investigate the applicability of A. scholaris extract as a cosmetic ingredient; basically we have measured its ability to inhibit the release of pro-inflammatory cytokines, including MCP-1 (monocyte chemotactic protein-1), IL-6, and IL-8, thus providing anti-inflammation effect on the human keratinocytes. In an anti-inflammatory assay, measuring the degree of inhibiting inflammatory cytokines release in human normal keratinocyte HaCat cells, we have observed that the ethanol extract of A. scholaris significantly inhibit cytokine production in 1µM retinoic acid treatment. We have also found that our extract, whose concentration is 50ppm, inhibits the release of MCP-1 and IL-6 by 81.2% and 79.7%, respectively. Moreover, our extract has inhibited the release of IL-8 by 72.2% at concentration of 100ppm, which is remarkably comparable to the result of non-treated condition.