Bacterial Derivatives of Lactococcus lactis and Ectoin for Atopic Dermatitis: Dermal Compatibility and Cosmetic Acceptability

Abstract

Introduction: Atopic dermatitis (AD) is a chronic skin disease characterized by disturbance of the skin barrier function. Recent studies have shown that application of non-viable bacterial derivatives can strengthen the barrier function and reduce signs of inflammation. Objectives: To assess skin compatibility and cosmetic acceptability of a new emollient for AD based on bacterial derivatives (lysate of Lactococcus lactis) and ectoin. Methods: Four studies were conducted: an in vitro evaluation of irritation potential using the Hen's Egg Test on the chorioal-lantoic membrane (HET CAM); an allergenic potential test to confirm the absence of dermal sensitization in healthy volunteers (HRIPT); a skin compatibility study in volunteers with atopic tendency skin (Open test) and a cosmetic acceptability test in healthy pediatric volunteers. Responses in all studies were visually evaluated by a dermatologist or pediatrician, scoring potential derma-tological reactions and recording any feeling of discomfort at the time of examination. Results: The HET-CAM test showed irritation potential similar to other products in the same category. No volunteer or child participating in the studies showed any skin reactions or feelings of discomfort. HRIPT discarded allergenic potential and verified that no components induce sensitization reactions. Open test confirmed good skin compatibility in atopic skin. Finally, the test on children showed excellent tolerability, cosmetic acceptability and satisfaction among the parents. Conclusions: Both, the in vitro and in vivo studies, confirmed the good tolerability, skin compatibility and cosmetic acceptability of this new emollient containing lysate of Lactococcus lactis and ectoin. The emollient represents a new approach for restitution of the cutaneous barrier in patients with AD, through the topical application of the lysate of probiotic bacteria, which acts on the epidermis thereby strengthening the skin barrier. References: Guéniche A et al. Bifidobacterium longum lysate, a new ingredient for reactive skin.