Cotton versus medical face mask influence on skin characteristics during COVID-19 pandemic: A short-term study.

BACKGROUND: In the still ongoing COVID-19 pandemic, one of the main prevention strategy remain to be the use of protective face masks. Changes in skin characteristics and dermatological problems related to wearing different types of masks have been observed. The aim of this study was to compare the short-term effects of cotton versus medical masks on skin biophysical parameters in general population. MATERIALS AND METHODS: Twenty-eight human volunteers were enrolled and divided in cotton mask and medical mask wearing groups. We measured four skin biophysical parameters: trans-epidermal water loss (TEWL), stratum corneum hydration (SCH), skin pH, and erythema index (EI) before and 3 h after wearing masks on both uncovered and mask-wearing face area. RESULTS: TEWL increased after 3 h on exposed skin in cotton mask group and slightly decreased in medical mask group There was an increase in SCH after 3 h of wearing protective face masks in both groups. pH of the covered skin slightly decreased while EI increased after 3 h in both groups; changes were not statistically significant. Parameters did not change significantly on uncovered skin. CONCLUSION: There were no differences between the influence of cotton versus medical protective masks on the skin of healthy volunteers in our study. Both types of masks could be recommended for short-time protection in individuals with healthy skin during COVID-19 pandemic.

Emulsions with alkyl polyglucosides as carriers for off-label topical spironolactone - safety and stability evaluation.

Androgens play an important role in the pathogenesis of acne. Being an anti-androgen drug with many side effects, spironolactone has recently been used in dermatology as a topical therapy for acne. Off-label drug use in dermatology is common, although those drugs are basically available as compounded formulations; the choice of a proper vehicle is often neglected in that case. Alkyl polyglucosides (APGs) are a FDA certified class of polyethylene glycol (PEG)-free surfactants produced from the renewable resources. Following the preformulation tests, two different APG emulsifiers were used in this study to stabilize emulsions as carriers for topical spironolactone. Assessment of the physical stability of emulsions per se and after incorporation of 5% of spironolactone was performed using polarization microscopy, electrical conductivity and pH measurements. The skin irritation profile and moisturizing potential was assessed in vivo on human volunteers. APG-based emulsions per se and with 5% of spironolactone showed acceptable skin irritation profiles and significant potential for skin hydration, which is important in acne treatment. Good physical stability and satisfying preliminary safety profile of all investigated samples were also obtained showing that moisturizing APG-based emulsions could be promoted as vehicles for off-label topical spironolactone.

Usnea barbata CO2-supercritical extract in alkyl polyglucoside-based emulsion system: contribution of Confocal Raman imaging to the formulation development of a natural product.

Topical treatment of skin infections is often limited by drawbacks related to both antimicrobial agents and their vehicles. In addition, considering the growing promotion of natural therapeutic products, our objective was to develop and evaluate naturally-based emulsion system, as prospective topical formulation for skin infections-treatment. Therefore, alkyl polyglucoside surfactants were used for stabilization of a vehicle serving as potential carrier for supercritical CO2-extract of Usnea barbata, lichen with well-documented antimicrobial activity, incorporated using two protocols and three concentrations. Comprehensive physicochemical characterization suggested possible involvement of extract's particles in stabilization of the investigated system. Raman spectral imaging served as the key method in disclosing extract's particles potential to participate in the microstructure of the tested emulsion system via three mechanisms: (1) particle-particle aggregation, (2) adsorption at the oil-water interface and (3) hydrophobic particle-surfactant interactions. Stated extract-vehicle interaction proved to be correlated to the preparation procedure and extract concentration on one hand and to affect the physicochemical and biopharmaceutical features of investigated system, on the other hand. Thereafter, formulation with the best preliminary stability and liberation profile was selected for further efficiency and in vivo skin irritation potential evaluation, implying pertinent in vitro antimicrobial activity against G+ bacteria and overall satisfying preliminary safety profile.

Estimation of dermatological application of creams with St. John's Wort oil extracts.

Oleum Hyperici, the oil extract of St. John's Wort (SJW), is one of the oldest folk remedies, traditionally used in the topical treatment of wounds, bruises, ulcers, cuts, burns, hemorrhoids and also as an antiseptic. Considering the advantageous characteristics of emulsion applications, in the present study we have formulated three O/W creams containing 15% (w/v) of SJW oil extract as an active ingredient. The aim was to estimate dermatological application of the prepared creams for the abovementioned indications. The extracts were prepared according to the prescriptions from traditional medicine, however with different vegetable oils used as an extractant, namely: Olive, palm and sunflower oil. The investigated O/W creams demonstrated significant antiinflammatory effects in an in vivo double-blind randomized study, using a sodium lauryl sulphate test. Both skin parameters assessed in the study (electrical capacitance and erythema index), were restored to the baseline value after a seven-day treatment with the tested creams. Almost all investigated SJW oil extracts and corresponding creams displayed the same antimicrobial activity against the most of the investigated microorganisms with obtained minimal inhibitory concentrations values of 1,280 µg/mL, 2,560 µg/mL or >2,560 µg/mL.

Polyglycerol Ester-Based Low Energy Nanoemulsions with Red Raspberry Seed Oil and Fruit Extracts: Formulation Development toward Effective In Vitro/In Vivo Bioperformance.

This study focuses on the development of biocompatible oil-in-water (O/W) nanoemulsions based on polyglycerol esters, as promising carriers for natural actives: red raspberry seed oil-RO and hydro-glycolic fruit extracts from red raspberry-RE and French oak-FE. Nanoemulsions were obtained via phase inversion composition (PIC) method at room temperature by dilution of microemulsion phase, confirmed by visual appearance, percentage of transmittance, microscopic, rheological and Differential Scanning Calorimetry (DSC) investigations. The results have shown that the basic RO-loaded formulation could be further enriched with hydro-glycolic fruit extracts from red raspberry or French oak, while keeping a semi-transparent appearance due to the fine droplet size (Z-ave: 50 to 70 nm, PDI value ≤ 0.1). The highest antioxidant activity (~92% inhibition of the DPPH radical) was achieved in the formulation containing both lipophilic (RO) and hydrophilic antioxidants (FE), due to their synergistic effect. The nanoemulsion carrier significantly increased the selective cytotoxic effect of RO towards malignant melanoma (Fem-X) cells, compared to normal human keratinocytes (HaCaT). In vivo study on human volunteers showed satisfactory safety profiles and significant improvement in skin hydration during 2 h after application for all nanoemulsions. Therefore, polyglycerol ester-based nanoemulsions can be promoted as effective carriers for red raspberry seed oil and/or hydro-glycolic fruit extracts in topical formulations intended for skin protection and hydration.

A 10% Lactobionic acid-containing moisturizer reduces skin surface pH without irritation-An in vivo/in vitro study.

BACKGROUND/OBJECTIVES: Stratum corneum acidification is a newer strategy in management of inflammatory dermatoses; acidifying emollients are normally used for that purpose. However, a decrease in pH of the skin is commonly connected to an increase in irritation. The aim of this study was to investigate whether lactobionic acid (LA), cosmeceutical active and "superacid" belonging to the class of alpha-hydroxy acids (AHAs), could decrease pH of skin surface without irritation. METHODS: Safety profile of emulsion based on alkyl polyglucosides (APGs) sugar emulsifiers with 10% LA was evaluated in vitro (acute skin irritation test using cytotoxicity assay), and in vivo in safety study employing measurements of the relevant biophysical human skin parameters upon cessation of 24 hours occlusive treatment: transepidermal water loss (TEWL), stratum corneum hydration (SCH), and skin erythema index (EI). The effect on the pH of human skin surface was investigated by pH measurements prior and 1 hour after application of the emulsion with 10% LA. RESULTS: The pH of the skin was significantly reduced after application of LA-containing emulsion. The results for in vitro skin irritation potential assessment were in line with the in vivo safety study, indicating a satisfactory safety profile of both APG-based emulsion vehicle per se and emulsion with 10% LA. CONCLUSION: Lactobionic acid (10%) in emulsion based on APGs reduces skin surface pH without irritation and skin barrier impairment; it could be proposed as an alternative to low-molecular AHAs in acidifying emollients.

Towards a modern approach to traditional use: in vitro and in vivo evaluation of Alchemilla vulgaris L. gel wound healing potential.

ETHNOPHARMACOLOGICAL RELEVANCE: Alchemilla vulgaris is an important remedy in European folk medicine, known for its astringent and anti-inflammatory properties; it is traditionally used to heal gynecological and gastrointestinal diseases. Despite its folkloric use in wound healing, there is a lack of scientific data to support this therapeutic application. AIM OF THE STUDY: To analyze the wound healing potential of different solvent A. vulgaris extracts per se and after incorporation into hydrogels as topical vehicles, using two complementary methods - in vitro wound healing assay with L929 fibroblasts and in vivo assessment of skin barrier repair potential. Besides scientific justification of the traditional usage, we aimed to ephasize the importance of a proper vehicle for herbal extracts. The wound healing activity has been connected to the chemical profile of the investigated extracts, their antioxidative properties, but also to pH of the investigated gels and their mechanical characteristics. MATERIALS AND METHODS: Antioxidant activity of investigated extracts was estimated using both 2,2-diphenyl-1-picrylhydrazyl and ß-carotene/linoleic acid models. Chemical profile was achieved applying spectrophotometric and HPLC methods. In vitro scratch assay with L929 fibroblasts, and in vivo study of skin barrier repair potential of hydrogels with A. vulgaris extracts on human skin employing biophysical measurements, were performed in order to confirm the wound healing potential of A. vulgaris. Texture analysis of the gels was performed alongside the pH measurements. RESULTS: All tested extracts and gels accelerated the wound healing process while the effect of ethanolic extract on migration of fibroblasts was the most pronounced. The highest extent of wound closure was also observed for the ethanolic extract. The most favorable effect on in vitro wound healing was observed for gel with propyleneglycolic extract. Results of in vivo study were in line with in vitro findings. Healing potential may be attributed to phenolic compounds found in A. vulgaris extracts, low pH of the gels, and the satisfying antioxidant activity of the extracts. Parameters obtained by textural analysis indicated satisfying mechanical properties of the gels, relevant to topical application. CONCLUSION: Our study offers pharmacological evidence on the folkloric use of A. vulgaris in wound treatment, particularly after incorporation into hydrogel, and underlines an importance of a proper vehicle for incorporation of herbal extracts intended for topical treatment.

Alp Rose stem cells, olive oil squalene and a natural alkyl polyglucoside emulsifier: Are they appropriate ingredients of skin moisturizers - in vivo efficacy on normal and sodium lauryl sulfate - irritated skin?.

Background/Aim: Since skin moisturization may be achieved by both actives and chosen carrier, plant stem cells, squalene and natural alkyl polyglucoside emulsifier may be potential components of contemporary cosmetic products. The aim of the study was in vivo evaluation of the skin irritation potential and the efficacy of Alpine Rose stem cells incorporated into li-posomes and olive oil squalene as ingredients of moisturizing creams, with respect to the novel emulsifier used for creams' stabilization. Methods: With the employment of noninvasive skin biophysical measurements, skin hydration (EC), transepi-dermal water loss (TEWL), erythema index (EI) and viscoelas-ticity were measured on 76 healthy volunteers. In the first phase, skin irritation after a 24-hour occlusion and the long-term efficacy of creams (a 21-day study) on healthy skin were evaluated. Phase II of the study focused on the cream efficacy assessment after a 6-day treatment of sodium lauryl sulfate-irritated skin. Results: After a 24-hour occlusion, there were no significant changes in the EI for any tested sample. In the second phase of the study, the EI was not significantly altered for the cream containing squalene, while the application of all active samples resulted in a significant reduction of TEWL. In both phases of the study an EC increase was recorded, espe-cially for the squalene-containing cream. Conclusion: Due to the lack of skin irritation and skin barrier impairment along with the marked hydration effect, it could be said that the in-vestigated actives incorporated into alkyl polyglucoside emulsi-fier-stabilized creams may be safely applied as ingredients for "tailor-made" cosmetic moisturizers intended for normal and dry skin care, whereas olive oil squalene could be used for the treatment of irritated or sensitive skin as well. [Projekat Ministarstva nauke Republike Srbije, br. TR34031]

Lactobionic acid in a natural alkylpolyglucoside-based vehicle: assessing safety and efficacy aspects in comparison to glycolic acid.

BACKGROUND/AIMS: Lactobionic acid (LA) is a newer cosmeceutical active belonging to the class of alpha-hydroxyacids (AHAs), showing advantages over them. The aim of part I of this study was to compare efficacy and irritation potential of LA vs. glycolic acid (GA) from two types of vehicles - gel and emulsion. In part II, effects of LA-containing emulsions based on a new, natural emulsifier of alkylpolyglucoside (APG) type were evaluated. METHODS: Skin bioengineering was used on 77 healthy volunteers to assess: color as erythema and melanin (MI) index, transepidermal water loss, electrical capacitance and pH of the skin. In part I of the study, the parameters were measured after occlusion and periodically during 2 weeks of test samples application; in part II parameters were measured periodically during 4 weeks. RESULTS/CONCLUSION: LA-containing samples has produced better skin performance when compared with corresponding GA-containing ones, particularly the lack of both skin irritation and skin barrier impairment. When used in vehicles based on a new APG-emulsifier, LA and GA have shown better efficacy, emphasizing the importance of vehicle on the effects of topical actives. LA (6%) in the emulsion based on APGs could be proposed as an alternative to low-molecular AHAs in cosmeceuticals.