Comparison of linoleic acid-containing water-in-oil emulsion with urea-containing water-in-oil emulsion in the treatment of atopic dermatitis: a randomized clinical trial

The Influence of Antioxidant Plant Extracts on the Oxidation of O/W Emulsions

The demand for natural cosmetics has steadily increased in recent years. However, challenges occur especially in quality preservation regarding oxidative spoilage of natural cosmetic products, as the use of synthetic preservatives and antioxidants is limited. Therefore, it is important to find nature-based ingredients to ensure shelf life in natural cosmetic formulations. As a result, potential is seen in the use of plant-based antioxidant extracts. The aim of this work was to determine the suitability of the method combination by measuring the antioxidant activity, oxygen concentration, and volatile oxidation products via gas chromatography (hexanal) for the characterization of the influence of some plant extracts on the oxidative stability of natural cosmetic emulsions. Plant extracts of Riesling (Vitis vinifera) pomace, apple (Malus domestica) pomace, coffee (Coffea arabica) grounds, cocoa (Theobroma cacao) husk, and coffee (Coffea arabica) powder extract were incorporated in stable O/W emulsion formulations, while an emulsion without extract functioned as blank. Afterwards, the emulsions were subjected to 3-month accelerated storage tests with and without light exposure. Their oxygen uptake was investigated, and headspace gas chromatography measurements were performed to detect the fatty acid oxidation products formed during oxidative processes in the samples. The results showed that all emulsion samples under light exposure had a higher oxygen uptake and an increase in the characteristic fatty acid oxidation products compared with those stored under light exclusion. However, differences in oxygen uptake under light exposure were observed depending on the plant extract. Therefore, for O/W emulsions, the daily oxygen consumption rate correlated exponentially with the antioxidant activity, and the hexanal concentration correlated linearly with the daily oxygen consumption rate.

The Role of Preservatives and Multifunctionals on the Oxidation of Cosmetic O/W Emulsions

Preservatives are typically used to protect cosmetic products from microbial spoilage. However, there is evidence that some preservatives can increase oxidation in O/W emulsions. This could have disadvantages for product quality, efficacy, and consumer health and well-being. Therefore, the impact of preservatives or multifunctionals on oxidation should be quantified. For this purpose, five O/W emulsions with different preservatives were prepared and stored. During storage, the oxygen concentration in the headspace of the samples was studied. The samples showed significant differences in their oxygen uptake and daily oxygen consumption rate. Thus, the preservatives used in this study had an influence on oxidation.

Development, Characterization, and Clinical Investigation of a New Topical Emulsion System Containing a Castanea sativa Spiny Burs Active Extract

The study focused on the development and characterization of an O/W emulsion for skincare containing Castanea sativa spiny burs extract (CSE) as functional agent. The emulsion was stable and had suitable physicochemical and technological properties for dermal application and CSE showed no cytotoxicity in spontaneously immortalized keratinocytes (HaCaT) at active concentrations. A single-blind, placebo-controlled, monocentric study was designed to evaluate the skin tolerability and the skin performance of the CSE-loaded emulsion on healthy human volunteers. An improvement was observed in skin biomechanical properties such as hydration, skin elasticity and a reduction in the periorbital wrinkles in 30 days without altering the skin barrier function, sebum, pH, and erythema values. A significant skin moisturizing effect was detected while the skin barrier function was preserved. The selected natural ingredient combined with the designed formulation and the optimized preparation method has led to a final product that satisfies the physico-chemical and technological requirements underlying the safety of use and the formulative stability over time. With no negative skin reactions and highly significant effects on skin elasticity, wrinkles, and moisturization, the CSE-based emulsion achieved very satisfying outcomes representing a promising functional formulation for skin care.

Urea in Dermatology: A Review of its Emollient, Moisturizing, Keratolytic, Skin Barrier Enhancing and Antimicrobial Properties

Urea is a hygroscopic molecule (capable of absorbing water) present in the epidermis as a component of the natural moisturizing factor (NMF) and is essential for the adequate hydration and integrity of the stratum corneum. Urea improves skin barrier function including antimicrobial defense by regulating gene expression in keratinocytes relevant for their differentiation and antimicrobial peptide production. It also plays a fundamental role in regulating keratinocyte proliferation. One of the first uses of urea in modern medicine was the topical treatment of wounds due to its proteolytic and antibacterial properties. At present, urea is widely used in dermatology to improve skin barrier function and as one of the most common moisturizers and keratolytic agents. Urea-containing formulations are available in diverse formulations and concentrations. Multiple clinical trials on the use of urea-containing formulations have shown significant clinical improvement in many of the dermatosis presenting with scaly and dry skin such as atopic dermatitis, ichthyosis, xerosis, seborrheic dermatitis and psoriasis, among others. Furthermore, urea can increase skin penetration and optimize the action of topical drugs. Urea-based products are well tolerated; their side effects are mild and are more frequent at high concentration. Here, we present a review of the use of urea in dermatology, discussing its mechanism of action, safety profile and frequent indications.

Advantages of Hyaluronic Acid and Its Combination with Other Bioactive Ingredients in Cosmeceuticals

This study proposes a review on hyaluronic acid (HA) known as hyaluronan or hyaluronate and its derivates and their application in cosmetic formulations. HA is a glycosaminoglycan constituted from two disaccharides (N-acetylglucosamine and D-glucuronic acid), isolated initially from the vitreous humour of the eye, and subsequently discovered in different tissues or fluids (especially in the articular cartilage and the synovial fluid). It is ubiquitous in vertebrates, including humans, and it is involved in diverse biological processes, such as cell differentiation, embryological development, inflammation, wound healing, etc. HA has many qualities that recommend it over other substances used in skin regeneration, with moisturizing and anti-ageing effects. HA molecular weight influences its penetration into the skin and its biological activity. Considering that, nowadays, hyaluronic acid has a wide use and a multitude of applications (in ophthalmology, arthrology, pneumology, rhinology, aesthetic medicine, oncology, nutrition, and cosmetics), the present study describes the main aspects related to its use in cosmetology. The biological effect of HA on the skin level and its potential adverse effects are discussed. Some available cosmetic products containing HA have been identified from the brand portfolio of most known manufacturers and their composition was evaluated. Further, additional biological effects due to the other active ingredients (plant extracts, vitamins, amino acids, peptides, proteins, saccharides, probiotics, etc.) are presented, as well as a description of their possible toxic effects.

Urea-containing topical formulations

Urea is a well-known moisturiser and keratolytic topical agent. As it is widely used in dermatology, several formulations at different concentrations have been marketed: lotions, creams, foams, ointments, gels and lacquers. Availability of different vehicles and concentration may vary in different countries, but in general products at low, medium and high urea concentration are accessible worldwide. The proper formulation should be chosen according to the disorder to treat, its severity, body areas involved and patients' preference.

Clinical evidences of urea at low concentration

Urea is a hygroscopic molecule that, because of its moisturising properties, is topically used for the treatment of skin dryness at concentrations ranging from 2% to 12% in different formulations. Based on existing literature, low-concentration urea-containing products are effective in the treatment and/or prevention of xerosis in some skin disorders such as ichthyosis, atopic dermatitis and psoriasis, or unrelated to specific skin diseases. Generally, urea formulations at low concentration are well-tolerated and suited for the treatment of large skin areas, once or twice daily, even for a long period of time. At low concentrations stinging and burning sensation is rare and transient, whit no reported sensitisation despite its widespread use.

Efficacy of Nonprescription Moisturizers for Atopic Dermatitis: An Updated Review of Clinical Evidence

Twice-daily moisturization is recommended by international guidelines as the bedrock of the management of atopic dermatitis (AD). Moisturizers should be selected based on proven clinical effectiveness in improving the skin barrier and improving the symptoms of AD. We searched the PubMed database for clinical trials assessing daily moisturization for the treatment of AD published between 2006 and 2019. Studies had to assess the efficacy of commercially available moisturizers using objective measures of corneometry, transepidermal water loss, or incidence of flare as endpoints, and treatments had to be currently available to patients. Clinical studies showed that moisturization (typically twice daily) significantly improved the skin barrier in adults and children with AD. Longer-term flare studies showed that daily moisturization reduced the incidence of flares and extended the time between flares. Proactive moisturization of infants at high risk of developing AD may reduce its manifestation. Therapeutic moisturizers for AD are specifically formulated with ingredients that target symptoms of AD, such as itch, inflammation, or compromised skin barrier. The US FDA requires that any moisturizer available in the USA and claiming to treat AD must contain colloidal oatmeal. Healthcare providers can maximize compliance and outcomes by educating patients on the benefits of liberally applying a therapeutic moisturizer twice daily to support the skin barrier and help reduce the incidence of flares. Specific recommendations should be for clinically tested moisturizers evaluated using objective, validated skin assessments.

Trends in nanoformulations for atopic dermatitis treatment

INTRODUCTION

Immunological skin dysfunctions trigger the synthesis and release of inflammatory cytokines, which induce recurrent skin inflammation associated with chronic itching, inefficient barrier behavior, and reduced skin hydration. These features characterize a multifactorial chronic inflammatory disease atopic dermatitis (AD). AD therapy includes anti-inflammatory drugs and immunosuppressors as well as non-pharmacological alternatives such as emollients, moisturizers, and lipids (ceramides, phospholipids) for modulating the skin hydration and the barrier repair. However, these treatments are inconvenient with low drug skin penetration and insufficient maintenance on the application site.

AREAS COVERED

Nanotechnology-based therapies can be a great strategy to overcome these limitations. Considering the particular skin morphological organization, SC lipid matrix composition, and immunological functions/features related to nanocarriers, this review focuses on recent developments of nanoparticulate systems (polymeric, lipid-based, inorganic) as parent or hybrid systems including their chemical composition, physico-chemical and biopharmaceutical properties, and differential characteristics that evaluate them as new effective drug-delivery systems for AD treatment.

EXPERT OPINION

Despite the several innovative formulations, research in nanotechnology-based carriers should address specific aspects such as the use of moisturizers associated to pharmacological therapies, toxicity studies, scale-up production processes and the nanocarrier influence on immunological response. These approaches will help researchers choose the most appropriate nanocarrier system and widen nanomedicine applications and commercialization.

Unsaturated fatty acid-enriched extract from Hippophae rhamnoides seed reduces skin dryness through up-regulating aquaporins 3 and hyaluronan synthetases 2 expressions

Background

Seed oil of sea buckthorn (SBT) is well known to contain high amount of polyunsaturated fatty acid (PUFA), and PUFA is generally acknowledged to promote skin hydration by reducing trans‐epidermal water loss (TEWL).

Aims

The present study is aimed to investigate that skin hydration offered by SBT seed oil is whether through up‐regulating AQP3 or HAS2 expression.

Methods

MTT assay was performed to detect cytotoxicity of SBT seed oil, and then, PCR was carried out to explore whether SBT seed oil can increase AQP3 mRNA expression in normal human epidermis keratinocytes (NHEK) cells or not. Immunofluorescence (IF) and Western blot analysis were used to test the protein level expression of AQP3 and HAS2 influenced by SBT seed oil in NHEK cells or in reconstructed epidermis skin model.

Results

According to the result of MTT assay, all test concentration of SBT seed oil showed no cytotoxicity to cells. 10 μg/mL SBT seed oil treatment evidently increased AQP3 mRNA level compared to negative control (NC). IF and Western blot analysis results demonstrated that AQP3 and HAS2 protein levels in NHEK cells treated with 10 μg/mL SBT seed oil were much higher than that of NC. Finally, treatment with 10 μg/mL SBT seed oil substantially up‐regulated expression of AQP3 and HAS2 protein in reconstructed epidermis skin model in comparison to NC.

Conclusions

In summary, our study first proved that SBT seed oil can improve skin hydration through increasing AQP3 and HAS2 expressions.

Diagnosis and management of moderate to severe atopic dermatitis in adolescents. A Consensus by the Italian Society of Dermatology and Venereology (SIDeMaST), the Italian Association of Hospital Dermatologists and Public Health (ADOI), the Italian Association of Hospital and Territorial Allergists and Immunologists (AAIITO), the Italian Society of Allergy, Asthma and Clinical Immunology (SIAAIC), the Italian Society of Pediatric Allergy and Immunology (SIAIP), the Italian Society of Allergological, Occupational and Environmental Dermatology (SIDAPA), and the Italian Society of Pediatric Dermatology (SIDerP)

Atopic dermatitis (AD) is a chronic inflammatory disease with increasing global incidence, which has a multifactorial pathogenesis and a variable expressivity. Clinical features of AD are different in adults compared to children, but it is well recognized the substantial impact of the disease on patients' quality of life at any age. Indeed, little is known about AD in adolescence, a period of life generally associated with high psychological burden and vulnerability to depression. Guidelines for the management of AD are available for both children and adults but specific guidelines for the diagnosis and treatment of AD in adolescents are lacking. Seven Italian scientific societies of dermatologists, allergists, and pediatric allergists joined in a specific meeting to provide practical guidance for the diagnosis and management of moderate-to-severe adolescent AD suitable for the Italian clinical practice. Through a modified Delphi procedure, consensus was reached by 59 Italian experts in the management of AD on 20 statements covering five areas of interest about adolescent AD, including disease complexity, burden and social impact, diagnosis and definition of severity, current treatments, and new biologic therapies. This paper reports recommendations for the diagnosis and management of AD specifically in adolescents, pointing out some peculiar clinical features and focusing on the choice of medications. Dupilumab, the first biologic approved for the treatment of adolescents with AD, represents a useful treatment option due to its efficacy and reassuring safety profile.

Comparing the Potential for Irritation of a Ceramide-Based Moisturizer with a Urea-Based Moisturizer for Pediatric Atopic Dermatitis

Introduction

Moisturizers are one of the mainstays of the topical treatment of atopic dermatitis (AD). One of the adverse effects of moisturizers is skin irritation, especially on excoriated AD skin. We compared the potential for irritation of two commercially available moisturizer products for the treatment of AD: a ceramide-based moisturizer (Ceradan^® Cream; Hyphens Pharma Pte Ltd, Singapore) and a urea 5% moisturizer (Aqurea Lite Cream; ICA Pharma Pte Ltd, Singapore).

Methods

We performed a prospective single-blind randomized controlled study recruiting AD patients aged between 8 and 16 years with symmetrical or near symmetrical scratch marks (excoriations) of at least grade 2 to 3 severity score, according to the Eczema Area and Severity Index (EASI), over bilateral antecubital fossae. Subjects were randomized to receive the ceramide-based moisturizer to either the left or right antecubital fossa or urea 5% cream to the other antecubital fossa. Subjects were asked to grade the immediate skin irritation of both creams on a standard visual analogue scale (VAS) and which cream they would prefer to use as a daily moisturizer. Primary outcome was the mean irritant score of each cream, and secondary outcome was the subjects’ preference of either cream as their daily moisturizer.

Results

A total of 42 participants were enrolled with a mean age of 11 years 5 months. The ceramide-based cream had a significantly lower mean VAS score (mean 0.69, SD = 1.63) for irritation compared with urea 5% cream (1.43, SD = 1.64) (p = 0.035). More participants also preferred the ceramide-based cream over urea 5% cream (62% versus 38%) as their daily moisturizer, but this did not reach statistical significance (p = 0.164).

Conclusions

A ceramide-based moisturizer may be considered as a suitable choice for children to minimize irritation from moisturizer treatment for AD.

Clinical use of Capilen, a liposomal cream based on fresh plant extracts enriched with omega fatty acids

The skin is the largest organ in the human body; beyond its regulatory and sensory roles, it is meant to protect and act like a barrier against foreign matter. Products intended to restore the skin health should reintegrate the structure of the stratum corneum in which the corneocytes are surrounded by the intercellular lipid lamellae that maintain both corneum integrity and skin permeability barrier. Capilen is a specific liposomal formulation based on a technology through which highly concentrated fresh plant extracts are conveyed into a jelly-like liposomal vehicle and combined with plant-derived omega-3, -6, -7, and -9 fatty acids, phospholipids, and precursors of ceramides. Its components have been widely investigated and produced clinical benefits in atopic dermatitis, bedsores, scars, inflammatory lesions of the skin, and generally whenever signs of xerosis cutis were present. Liposomes contribute to restore the surface lipid layer of the skin and to deliver substances in the activity site. This liposomal cream was proven to limit and delay the occurrence of radiodermatitis in breast cancer patients, and as an add-on provided complete healing of bedsore lesions in geriatric subjects.

Overexpression of delta-12 desaturase in the yeast Schwanniomyces occidentalis enhances the production of linoleic acid

The oleaginous yeast Schwanniomyces occidentalis was previously isolated because of its excellent suitability to convert lignocellulosic hydrolysates into triacyl glycerides: it is able to use a broad range of sugars and is able to tolerate high concentrations of lignocellulosic hydrolysate inhibitors. Compared to other oleaginous yeasts S. occidentalis however produces a low content of unsaturated fatty acids. We show here that the linoleic acid content can be significantly improved by (over)expression Δ12-desaturases derived from S. occidentalis and Fusarium moniliforme. Expression was stable for the homologous expression but decreased during heterologous expression. Both homologous and heterologous expression of mCherry-Δ12-desaturase led to a 4-fold increase in linoleic acid from 0.02 g/g biomass to 0.08 g/g biomass resulting in the production of 2.23 g/L and 2.05 g/L of linoleic acid.

Topical urea in skincare: A review

Alterations in barrier function are associated with a number of skin diseases, including xerosis, atopic dermatitis, and psoriasis. Urea, a component of the natural moisturizing factor of the skin, plays an important role in the preservation of skin hydration and integrity. Several studies have investigated the effects of urea in the clinical setting. Here, we summarize the available clinical evidence regarding the effects of urea in the maintenance of healthy skin and management of skin disorders. At lower doses (≤10%), urea-containing topical formulations act as a skin moisturizer, while at higher concentrations (>10% urea), urea-based preparations exert a keratolytic action. Urea is also useful in combination therapies with anti-inflammatory and anti-fungal drugs, due to its activity as a penetration enhancer.