A Biomimetic Combination of Actives Enhances Skin Hydration and Barrier Function via Modulation of Gene Expression: Results of Two Double-Blind, Vehicle-Controlled Clinical Studies

INTRODUCTION

Xerosis cutis is characterized by a decreased stratum corneum (SC) hydration and an impaired skin barrier function. Urea, the most prevalent natural moisturizing factor (NMF), is currently considered the gold standard. Its efficacy can further be increased by combining urea with other NMF and skin barrier lipids (SBLs).

OBJECTIVE

We set out to evaluate physiological effects of a novel functional moisturizer containing 10% urea, additional NMF components, and a combination of SBLs on skin hydration and skin barrier integrity on a cellular and phenotypic level in female volunteers suffering from xerosis.

METHODS

Two double-blind, vehicle-controlled clinical studies were conducted. In the first study, 44 female subjects having very dry body skin applied the moisturizer or its vehicle twice daily to their volar forearms. Twenty-four hours after a single product application as well as 24 h after 2 weeks of treatment, SC hydration was measured by corneometry. Skin barrier function was assessed by transepidermal water loss 24 h and 48 h after 2 weeks of regular use. Twenty-four hours after 2 weeks of application, skin tape stripping was performed, and urea content was determined in the 3rd strip by means of high-performance liquid chromatography/tandem mass spectrometry. In the second study, 22 women with self-reported very dry skin applied the moisturizer or vehicle twice daily to their volar forearms for 2 weeks. Then, suction blister samples were obtained for gene expression analysis using RT-PCR.

RESULTS

Application of the actives led to significantly improved skin hydration and barrier function at all points in time. Compared to the vehicle, application of the moisturizer for 2 weeks resulted in a significant increase in SC urea content. Relative gene expression data revealed significant upregulation of genes associated with skin barrier function, hydration, differentiation, and lipid metabolism compared to the vehicle-treated area.

CONCLUSIONS

Overall, our data demonstrate that the functional moisturizer provides an adequate bioavailability of urea and a beneficial biophysical impact on xerotic skin. Topical treatment with a combination of urea and additional NMF as well as SBL can modify mRNA expression of important epidermal genes stimulating cellular processes and functions. The well-tolerated novel functional moisturizer stimulates molecular mechanisms involved in skin hydration and barrier function and is a profoundly effective treatment option for xerosis cutis.

Oral intake of specific bioactive collagen peptides reduces skin wrinkles and increases dermal matrix synthesis

Dietary consumption of food supplements has been found to modulate skin functions and can therefore be useful in the treatment of skin aging. However, there is only a limited number of clinical studies supporting these claims. In this double-blind, placebo-controlled study, the effectiveness of the specific bioactive collagen peptide (BCP) VERISOL® on eye wrinkle formation and stimulation of procollagen I, elastin and fibrillin biosynthesis in the skin was assessed. A hundred and fourteen women aged 45-65 years were randomized to receive 2.5 g of BCP or placebo, once daily for 8 weeks, with 57 subjects being allocated to each treatment group. Skin wrinkles were objectively measured in all subjects, before starting the treatment, after 4 and 8 weeks as well as 4 weeks after the last intake (4-week regression phase). A subgroup was established for suction blister biopsies analyzing procollagen I, elastin and fibrillin at the beginning of the treatment and after 8 weeks of intake. The ingestion of the specific BCP used in this study promoted a statistically significant reduction of eye wrinkle volume (p < 0.05) in comparison to the placebo group after 4 and 8 weeks (20%) of intake. Moreover a positive long-lasting effect was observed 4 weeks after the last BCP administration (p < 0.05). Additionally, after 8 weeks of intake a statistically significantly higher content of procollagen type I (65%) and elastin (18%) in the BCP-treated volunteers compared to the placebo-treated patients was detected. For fibrillin, a 6% increase could be determined after BCP treatment compared to the placebo, but this effect failed to reach the level of statistical significance. In conclusion, our findings demonstrate that the oral intake of specific bioactive collagen peptides (Verisol®) reduced skin wrinkles and had positive effects on dermal matrix synthesis.

Supplementation with Evelle® improves skin smoothness and elasticity in a double‐blind, placebo‐controlled study with 62 women

OBJECTIVE

To investigate whether nutritional intervention with a proprietary formulation and other micronutrients may favourably alter skin roughness and elasticity.

METHODS

Sixty-two women aged 45-73 years participated in a double-blind, placebo-controlled trial testing the efficacy of a proprietary oral supplement for skin nutrition (Evelle), for improvement of skin elasticity and roughness. The active ingredients were vitamins C and E, carotenoids, selenium, zinc, amino acids and glycosaminoglycans, blueberry extract and Pycnogenol.

RESULTS

Skin elasticity, measured using an optical cutometer, was found to be statistically significantly increased by 9% after 6 weeks of treatment compared with placebo (p=0.0351). Skin roughness, as evaluated by three-dimensional microtopography imaging, was found to be statistically significantly lowered by 6% compared with the control group after 12 weeks treatment (p=0.0157).

CONCLUSION

Evelle can potentially improve visible signs of cutaneous ageing.