The Natural Centella asiatica Extract Acts as a Stretch Mark Eraser: A Biological Evaluation

Stretch marks are far from exclusively appearing on pregnant women and appear whenever the body experiences rapid growth. Collagen fibres are altered in the dermis, which is associated with a loss of orientation, and the elastic network is disrupted, leading to a fibrotic organisation. This results in epidermal tearing that produces skin lesions. Centella asiatica (CAST) is a well-known medicinal plant rich in active triterpenic molecules and traditionally used to treat wounds and help skin repair. The aim of this study was to evaluate CAST extract as a natural way to solve stretch mark concerns and understand its mechanism of action. Fibroblast proliferation based on scratch assay model and their gene expression by RT-qPCR was first evaluated. At the ex vivo level, elastin fibres were quantified by immunofluorescence. The orientation of the collagen fibres and their occupation of the dermis were analysed after Sirius red staining and specific software analysis. We showed that CAST stimulated fibroblast proliferation and reduced extracellular matrix degradation and fibrosis. On a stretch-marked skin explant, CAST increased the occupation of collagen fibres and elastin production. Based on the mechanisms behind the formation of stretch marks, CAST restored the dermis network by optimising fibre organisation for a visible skin remodelling effect.