Cécile Bize, Erwan Le Gémébart, Elsa Hernandez, Christine Garcia
50th Annual ESDR Meeting
Dry skin is a common skin disorder among the general population. It is characterized clinically by rough, scaly, and often itchy skin that has lost its normal mechanical properties (especially a loss in elasticity). It is a sign of dysfunction of the epidermis, especially of the stratum corneum. This defective barrier function stimulates the production and the secretion of cytokines, which in turn may cause cutaneous inflammation and weaken the barrier. Indeed, barrier disruption may stimulate signaling cytokine cascades that engage not only the desired epidermal homeostatic response, but also inflammatory events involving the deeper layers of the skin and the endothelium. The elicitation of inflammation as a result of barrier disruption can maintain skin dryness creating a vicious circle that we called Inflamm’dryness.A botanical extract obtained from Helichrysum stoechas dedifferentiated cells was able to break this vicious circle. First of all, this extract induced a decrease of pro-inflammatory mediators such as PGE2 and promoted the synthesis of the beneficial molecules of resolution to regulate skin homeostasis (e.g. 15-HETE).
Moreover, histological and TEM analysis clearly showed that this active ingredient boosted the formation of stratum corneum: the thickness was increased by 77%. Moreover, the number of keratohyalin granules was increased by 49% and NMF content by 29%. TEM analysis also demonstrated that Helichrysum stoechas extract reduced intercellular spaces between the basal keratinocytes (-61%). Finally, this active ingredient helped restore the skin barrier function to limit dehydration by reducing tape-stripping-induced TEWL by 78%. In human volunteers with dry skin, this botanical extract increased moisturization (corneometer) by +32% vs. placebo. In human explants, the moisturization effect has been associated with an increase of 150% of the number of lacunae confirming hydration efficacy. To sum up, Helichrysum stoechas extract helped the resolution of inflammation of dry skin leading to a restoration of the skin barrier function and in fine, increased epidermal moisturization.
Seppic Research & Innovation, Paris La Défense, La Garenne Colombes