Epidermal barrier function in dry, flaky and sensitive skin: A narrative review.

The stratum corneum (SC)-the outermost layer of the epidermis-is the principal permeability and protective barrier of the skin. Different components of the SC, including corneocytes, natural moisturizing factor, a variety of enzymes and their inhibitors, antimicrobial peptides and lipids, work interactively to maintain barrier function. The main barrier properties of the SC are the limitation of water loss and the prevention of infection and contact with potentially harmful exogenous factors. Although the SC functions consistently as a protective barrier throughout the body, variations in functions and morphology occur across body sites with age and skin type. Healthy SC function also depends on the interplay between the chemosensory barrier, the skin's microbiome and the innate immune system. Dysregulation of SC barrier function can lead to the development of skin disorders, such as dry, flaky or sensitive skin, but the complete underlying pathophysiology of these are not fully understood. This review provides insight into the current literature and emerging themes related to epidermal barrier changes that occur in the context of dry, flaky and sensitive skin. Additional studies are needed to further elucidate the underlying aetiology of dry, flaky and sensitive skin and to provide tailored treatment.

Individual Article: Efficacy of Over-The-Counter Cream in Reducing Eczema Signs.

BACKGROUND: Eczema (also called atopic dermatitis) is a chronic, relapsing skin disease characterized by erythema, scaling, and pruritus. METHODS: Study 1. A double-blind, uncontrolled study in patients with mild-moderate eczema, ≥2 flares in prior 2 months, and baseline Scoring Atopic Dermatitis (SCORAD) score ≤15. Participants applied Eczema Flare-Up Relief Cream (EFRC) (N=65) BID for 56 days. Efficacy was assessed by SCORAD, patient-oriented SCORAD, skin sensitivity, Dermatology Life Quality Index (DLQI), and digital photography. Standard safety assessments were performed. STUDY 2: A 21-day open study of EFRC (N=50) to evaluate tolerability as well as its effect on eczema.  Results: Study 1. EFRC significantly reduced overall SCORAD scores from baseline to day 56 (11.6 to 4.9, or a 57% reduction). The patient-oriented SCORAD was reduced from 18.6 to 6.8 from baseline to day 56. At day 56, itch and pain improved in 70.4% of children and 62% of adults. DLQI scores were decreased by 75% in adults and 61% in children by day 56. Global skin sensitivity, assessed by the Sensiscale 10-item questionnaire, was 13.1 at baseline and 3.6 at day 56, an improvement of 72%. STUDY 2: EFRC improved eczema-prone skin after 7 and 21 days.  Conclusions: Study 1 showed that EFRC had good efficacy with significant reductions in overall SCORAD scores and subscores for the extent and intensity of eczema and subjective symptoms. Skin sensitivity also improved along with quality of life. Studies 2-3 also had significantly positive results and good tolerability. J Drugs Dermatol. 2023;22:10(Suppl 2):s5-9.

Glycerol and natural sugar-derived complex modulate differentially stratum corneum water-binding properties and structural parameters in an in vitro Raman-desorption model.

The epidermal protective functions are closely associated with skin hydration homeostasis. The understanding of different states of water binding is a rising concept in assessing topically applied formulations and their interaction within the stratum corneum (SC). In addition to global water content, primary bound water, partially bound water, and unbound water and barrier-related lipid lateral packing and protein secondary structure can be measured by Raman spectroscopy. This study aimed to establish an in vitro SC model to evaluate differences in the efficacy of a natural sugar-derived complex in combination with glycerol and a botanical extract in modulating SC water binding and structural proteins and barrier lipids. These compounds were selected due to their water-binding and soothing properties. The SC water profiles were assessed at the surface and in 8 µm SC depth. After a 12-hour hyperhydration and subsequent product incubation the measurements were performed during a 6 hours desiccation phase. The maximal water caption and the time until reaching a steady state are measured as well as water retention and resistance against water loss. Global water content, partially bound, and unbound water, as well as lipid and protein structures were assessed with confocal Raman microspectroscopy. Both the natural sugar-derived mixture and more pronounced, the same mixture with additional glycerol increased all three water-binding parameters at the surface and in 8 µm SC depth at the beginning and during the desiccation phase. Further addition of botanical extract did not result in an additional increase of the water-binding. All three formulations showed an increase in the lipid lateral packing values prevented the protein alteration as measured by ß-sheets signal compared to blank. The present model is suited for screening studies comparing the specific effects of different compounds on hydration states. The natural sugar-derived mixture Aquaxyl showed evidence for an improvement of all SC hydration states, lipid and protein structure which was further enhanced by the addition of glycerol 5%. This improvement was evidenced at the surface and within the SC for all hydration-related parameters, and the lipid as well the protein structures. The addition of botanical extract phytoessence blue daisy did not show further improvement.

An Open-Label, Intra-Individual Study to Evaluate a Regimen of Three Cosmetic Products Combined with Medical Treatment of Rosacea: Cutaneous Tolerability and Effect on Hydration.

INTRODUCTION: Although rosacea management includes general skincare, previous studies have not evaluated comprehensive skincare regimens as adjuvants to other treatments. METHODS: The primary objective of this open-label, intra-individual study of subjects with rosacea was to evaluate the cutaneous tolerability of a regimen consisting of Cetaphil PRO Redness Control Day Moisturizing Cream (once daily in the morning), Cetaphil PRO Redness Control Night Repair Cream (once daily in the evening) and Cetaphil PRO Redness Control Facial Wash (foam once in the morning and once in the evening). Secondary objectives were to evaluate the effect on transepidermal water loss (TEWL) and cutaneous hydration and to determine the subjects' evaluation of efficacy, tolerability and future use. A dermatologist examined subjects and measured TEWL and cutaneous hydration on day (D) 0, D7 and D21, when subjects ranked symptoms. Subjects completed a questionnaire on D21. RESULTS: The per-protocol population consisted of 42 subjects receiving treatment for rosacea. Eleven subjects developed adverse events, none of which were considered to be related to the skincare products. Five subjects showed signs or symptoms that were potentially associated with the skincare products that might suggest poor cutaneous tolerability; these were generally mild. TEWL decreased significantly by a mean of 17% on D7 and a mean of 28% on D21 compared with baseline (both P < 0.001). Skin hydration increased significantly by a mean of 5% on D7 (P = 0.008) and a mean of 10% on D21 (P < 0.001) compared with baseline. Subjects reported that the regimen was pleasant (98%) and effective (95%) and that it offered various benefits; 90% of subjects reported that they would like to continue to use the regimen and would buy the products. CONCLUSION: The skincare regimen improved skin hydration and skin barrier function in subjects receiving medical treatment for rosacea and was well tolerated. FUNDING: Galderma S.A.

Comparing skin characteristics and molecular markers of xerotic foot skin between diabetic and non-diabetic subjects: An exploratory study.

BACKGROUND: Xerosis cutis of the feet is one of the most common skin conditions among type 2 diabetics. Whether skin dryness among diabetic patients is different from 'general' skin dryness is unclear. The overall aim was to compare the structure, function and molecular markers of dry and cracked foot skin between diabetics and non-diabetics. METHODS: The foot skin of 40 diabetics and 20 non-diabetics was evaluated. A clinical assessment of skin dryness was performed and transepidermal water loss, stratum corneum hydration, skin surface pH, epidermal thickness, skin roughness, elasticity and structural stiffness were measured. Ceramides, natural moisturizing factors, histamines, proteins and molecular markers of oxidative stress were analyzed based on a non-invasive sampling method for collection of surface biomarkers. RESULTS: The mean number of superficial fissures in the diabetic group was nearly three times higher than in the non-diabetic group (11.0 (SD 6.2) vs. 3.9 (SD 4.2)). The skin stiffness was higher in the diabetic group and the values of almost all molecular markers showed considerably higher values compared to non-diabetics. Malondialdehyde and glutathione were lower in the diabetic sample. CONCLUSIONS: The high number of superficial fissures may be based on an increased stiffness of dry diabetic foot skin combined with different concentrations of molecular markers in the stratum corneum compared to dry foot skin of non-diabetics.

A novel moisturizer with high sun protection factor improves cutaneous barrier function and the visible appearance of rosacea-prone skin.

BACKGROUND: Consensus guidelines advocate general skincare for rosacea patients. OBJECTIVES: Two independent studies were performed to assess whether a tinted daily SPF-30 facial moisturizer (DFM30) improves barrier function of dry skin and the efficacy and tolerability of DFM30 on rosacea-prone skin. METHODS: In study 1, electrical capacitance (EC) and transepidermal water loss (TEWL) were measured at baseline, 2, 4, 8, and 24 hours after a single application of DFM30 and on a control site in 21 healthy females with dry skin. Study 2 evaluated 33 females with mild to moderate rosacea and nontransient erythema. Efficacy and tolerability after once-daily DFM30 were assessed using a chromameter, image analysis of photographs, and trained rater and patient evaluations up to day 22. RESULTS: In study 1, EC showed statistically significant increases at 2, 4, and 8 hours, and TEWL showed statistically significant decreases 2, 4, 8, and 24 hours after DFM30 application to healthy females compared to baseline. In study 2, covering skin redness improved significantly after DFM30 application on day 1; 33.3% showed improved covering skin redness compared to baseline. Patients reported significantly less redness on day 8 than day 3. Feelings of dryness and tightness/tension were lower 30 minutes after first application. Feeling of dryness was lower than baseline after 3 days, 1 and 3 weeks. Image analysis suggested redness was significantly lower on day 22 compared to baseline. Chromameter readings showed significantly lower erythema on the cheek compared to baseline. All patients stated that DFM30 relieves and neutralizes visible redness who also indicated that they would purchase DFM30, and the product was well tolerated. CONCLUSIONS: These studies show that DFM30 is suitable as part of the skincare regimens advocated by ROSacea COnsensus (ROSCO) for rosacea patients. DFM30 is an effective moisturizer that improves cutaneous barrier function and the appearance of rosacea-prone skin.

Evaluation of a novel very high sun-protection-factor moisturizer in adults with rosacea-prone sensitive skin.

BACKGROUND/OBJECTIVE: Rosacea-prone sensitive skin requires high sun-protection factor (SPF) moisturizers. This study evaluated Daylong Extreme SPF 50+ lotion, a novel cream containing five ultraviolet filters, two emollients, and three skin conditioners. SUBJECTS AND METHODS: This was an open-label, single-center study. On day 1, before treatment, subjects answered a questionnaire on their skin conditions and sunscreen habits, and both subjects and dermatologist evaluated skin status. Subjects applied the product once daily in the morning to the face for 21 days, and after approximately 3-5 minutes they assessed tolerability and short-term cosmetic acceptability in a questionnaire and daily diary. On day 22, the dermatologist and subjects evaluated skin status for long-term tolerance and cosmetic acceptability. RESULTS: The study enrolled 44 individuals (mean age 58.8 years, 91% female). At baseline, most subjects (39 of 44) showed erythema, and ~30% showed dryness and scaling. Dermatologists noted four cases of pustules and one case of papules. After 21 days' treatment with the product, the dermatologist reported significantly less erythema, dryness and scaling, three cases of pustules and two cases of papules. At baseline, ~75% of subjects noted a feeling of dryness, >50% reported tension, and nearly 25% reported tickling. After using the product for 21 days, subjects reported significantly less tension, dryness, and tickling. Some subjects noted itching and burning before and after using the product. One subject noted papules during treatment. Most subjects said that the product was pleasant, did not irritate the skin or cause stinging/burning, was easy to apply, quickly absorbed, and nongreasy, improved skin moisturization, helped prevent sun-provoked facial redness, did not worsen rosacea, and was easily incorporated into their skincare regimen. Half would switch to the product, and 80% of subjects would buy and recommend the product. CONCLUSION: The product was well tolerated in rosacea-prone subjects, producing objective and subjective improvements in skin status and symptoms.