(601m) The Mechanistic Study of Anti-Fibrotic Effect of Di-Rhamnolipids on Myofibroblast

Scar formation affects a growing number of people around the world, but its effective therapy is still in shortage. Di-rhamnolipid, a widely studied biosurfactant, has been found to protect skin from fibrosis. However, its mechanism remains unclear. This study will aim to illustrate the anti-fibrotic performance of rhamnolipids on myofibroblasts which mainly derive from local fibroblasts and play a dominate role in scar formation of skin. As we found, di-rhamnolipid at 100 ppm showed sensitive toxicity on myofibroblasts, but had no such effect on fibroblasts. Furthermore, the fibroblasts in green fluorescence enveloped myofibroblasts in red fluorescence when the two cells were mixed for forming aggregates, indicative of the higher membrane tension for myofibroblasts. Thus, to our presumption, di-rhamnolipid could elicit more sensitive toxicity to the cell which is of higher membrane tension. Additionally, the alteration of cytoskeleton and the apoptosis of myofibroblast were detected after the di-rhamnolipids exposure, which further illustrated the cytotoxicity of di-rhamnolipids. This work explains the anti-scarring effects of di-rhamnolipids by showing sensitive toxicity on myofibroblasts instead of fibroblasts as previously reported. These results will guide the application of di-rhamnolipids as an anti-scarring drug.