Skin aging is a multifaceted biological process characterized by the deterioration of skin structure and function, often linked to alterations in the skin barrier and its resident microbiota. Maintaining a healthy skin barrier and a balanced skin microbiome are increasingly recognized as crucial for preserving skin health and combating signs of aging. To address these challenges, a combined “in & out” approach, integrating oral supplements and topical treatments, has gained attention for its potential to nourish the skin from within while providing external benefits. This study investigates the efficacy of such an approach, specifically examining the combination of oral probiotics (Lactobacillus plantarum PBS067, Lactobacillus reuteri PBS072, and Lactobacillus rhamnosus LRH020) with topical ectoin and sodium hyaluronate in mitigating the signs of mild-to-moderate facial aging. The rationale behind this combination lies in the known benefits of probiotics for gut-skin health and the hydrating and protective properties of ectoin and sodium hyaluronate.
Methods:
This research employed a single-center, randomized, double-blind, placebo-controlled trial involving 96 Caucasian subjects with mild-to-moderate facial aging and sensitive skin. Participants were divided into four groups receiving active food supplement and placebo cosmetics (AFPC), placebo food supplement and active cosmetics (PFAC), active food supplement and active cosmetics (AFAC), or placebo food supplement and placebo cosmetics (PFPC) for 8 weeks. Skin parameters such as sebum content, hydration, wrinkles, elasticity, radiance, pores, and microbiome composition were assessed at baseline, after 4 weeks, and after 8 weeks, with short-term effects of topical products evaluated one-hour post-application. Compliance was monitored, and self-assessment questionnaires were used to gauge perceived efficacy.
Section-wise Key Points:
•Short-Term Results with Topical Product Application: One hour after a single application, the active serum significantly reduced wrinkle depth by 9.2% compared to placebo (3.9%)11. The active cream significantly increased skin hydration by 16.6% and skin radiance by 19.1%, also showing greater effects than the placebo cream.
•Primary Endpoints: After 8 weeks, skin moisturization significantly increased in all active groups (AFPC, PFAC, AFAC), with the highest increase in the AFAC group (+21.4%). The active food supplement groups (AFPC and AFAC) showed continuous improvement in moisturization from week 4 to week 8, suggesting a synergistic effect with topical treatments. Skin sebum content remained largely unchanged across groups, with a slight decrease in the AFAC group in week 8.
•Secondary Endpoints:
◦Skin Profilometry: Significant reductions in wrinkle depth were observed in all active groups, with the AFAC group showing the greatest reduction at week 8 (-16.5%). Improvement in skin smoothness was statistically significant only in the AFAC group.
◦Transepidermal Water Loss (TEWL): TEWL significantly decreased in the PFAC and AFAC groups after 4 and 8 weeks, indicating improved skin barrier function. The AFPC group also showed a significant decrease in week 8.
◦Skin Elasticity: Skin firmness (R0) and overall elasticity (R2) improved significantly in all active groups over 8 weeks, with the AFAC group showing the most pronounced improvements.
◦Skin Radiance: All active product groups showed a positive increase in skin radiance, with steady improvement from week 4 to week 8 in the AFPC and PFAC groups. The AFAC group also showed significant improvements.
◦Pores Size and Impurities: Pore size did not change significantly in any group. However, protoporphyrin distribution (impurities) decreased in all active groups, suggesting a detoxification effect.
◦Skin Microbiome: The active combination group (AFAC) showed a statistically significant difference in alpha diversity (Shannon and Simpson indices) between week 4 and 8, indicating a shift in microbial community structure. Specific changes in the relative abundance of Achromobacter, Gemella, Acetobacter, and Acinetobacter were noted in different active groups.
•Self-Assessment Questionnaire Output: Participants in all active groups reported positive evaluations of the products, with the highest proportion of positive responses in the AFAC group.
•Discussion: The study highlights the synergistic benefits of combining oral probiotics with topical ectoin and sodium hyaluronate in improving various skin aging parameters. The findings suggest that the oral probiotics contribute to sustained improvements in skin hydration and enhance the efficacy of topical treatments. The observed changes in skin microbiome composition in the active groups further support the notion that this “in & out” approach positively influences skin health.
This randomized, double-blind, placebo-controlled trial demonstrates the novel synergistic anti-aging effects of combining oral probiotics (Lactobacillus plantarum, Lactobacillus reuteri, and Lactobacillus rhamnosus) with topical ectoin and sodium hyaluronate. The combined treatment resulted in significant improvements in skin hydration, wrinkle depth, elasticity, radiance, and barrier function, outperforming individual treatments. The study’s findings underscore the importance of the gut-skin axis and the potential of microbiome-targeted interventions for skin health. Future research could explore the long-term sustainability of these effects and investigate the specific mechanisms driving the observed changes in skin microbiota and their contribution to skin rejuvenation in more diverse populations. The results suggest that integrating oral probiotics with topical treatments could be a promising strategy in the development of advanced anti-aging and skin health regimens.
Link to the study: https://www.mdpi.com/2079-9284/12/2/34
