Evaluation of the effect of an extract of Sphingomonas xenophaga present in a Thermal Spring Water in the management of sensitive skin associated with cutaneous vascular disorder

Abstract Objective La Roche Posay Thermal Spring Water (LRP TSW), which contains specific minerals and possesses a unique microbial composition, has proven anti‐oxidant, anti‐inflammatory, pre‐ and post‐biotic properties and an ability to improve skin barrier function. Our objective was to confirm the effectiveness of a biomass isolated from LRP TSW on inflammatory and vascular parameters in sensitive skin. Methods A fully characterized strain of Sphingomonas xenophaga was isolated from LRP TSW. An industrial fermentation process was developed to obtain a reproducible biomass (the ‘ferment extract’) in order to evaluate its effect on skin parameters in vitro and in vivo. Inhibition of pre‐kallikrein activity, which converts pro‐bradykinin into inflammatory vasoactive bradykinin, by the ferment extract was determined in vitro. In vivo, the effect of a 4‐week, twice‐daily application of a 2% ferment extract cream formulation on vascular disorders was investigated in a randomized study including 86 Caucasian female subjects presenting permanent redness and vascular disorder on the face in comparison to the cream vehicle. Results The ferment extract inhibited in a dose‐dependent manner pre‐kallikrein activity in vitro, inducing 46% and 97% inhibition at concentrations of 0.4% and 0.5%, respectively. In vivo after 28 days of twice‐daily applications of the ferment extract and vehicle, both treatments induced a significant decrease in vascular disorder as evaluated by clinical scoring (Dermascore® device with cross‐polarized light). The mean decrease in vascular disorder score from baseline was significantly greater ( p < 0.05) in the ferment extract group (−0.36) when compared to vehicle (−0.18). In addition, 60% of subjects in the group treated with the formulated ferment extract had a decreased score compared to 33% for the group treated with the vehicle. Conclusion Inhibition of the production of inflammatory vasoactive bradykinin by the ferment extract observed in vitro is in line with the anti‐inflammatory effects of the formulated extract as shown in subjects with facial vascular disorder. The results in this study suggest that this ferment extract is a potentially new active ingredient that could be used either alone or in combination with other soothing agents to target skin inflammatory pathways and to improve skin vascular disorder.