Dermatological Products Research Articles

In Vitro Skin Permeation Methodology for Over-The-Counter Topical Dermatologic Products.

For topically applied over-the-counter (OTC) products, the association of unwanted systemic exposure and adverse events may be difficult to ascertain without a recognition or determination of in vivo absorption. Evaluation of skin permeability using a validated in vitro permeation methodology can provide important information for both initial formulation selection and reformulation during the product life cycle. Additionally, a comparison of permeation rates between formulations using a validated methodology could reduce the number of nonclinical studies needed as part of reformulation. However, many in vitro permeation tests (IVPTs) have produced results with high variability and low reproducibility between study sites. It is unclear if this is due to a lack of a standardized protocol, or lack of control of multiple key experimental factors including skin source, preparation, receptor fluid, and study design. This review presents the authors perspective on the potential regulatory utility of IVPT and proposes steps to improve the accuracy and reproducibility of IVPT. The focus of this review is on topical dermatologic drugs with an initial emphasis on the OTC marketplace where reformulations are more common.

Regulatory Requirements and Innovation: A Comparison of the Dermatologic Antifungal Drug Product Markets in Brazil and United States

Development of novel dermatological topical products for the treatment of cutaneous fungal infections is a constant necessity, especially in developing countries. Through public health policies, many developing countries have facilitated in the last decades the entry of generic products, which can be superficially seen as a threat to innovation. To verify whether regulatory requirements, or the waiving of some requirements, could have an impact on innovation, we performed a detailed technical comparison of the dermatologic antifungal markets of Brazil and of the United States, taking Brazil as an example of a developing country with more lenient requirements regarding the registration of generic topical drug products. The official databank of ANVISA (DATAVISA) and of US Food and Drug Administration (Orange Book) were assessed for valid topical dermatological antifungal drug products registered. The Brazilian market has a greater number of registered drug products encompassing a greater variety of drug substances than the US, but the latter comprises more products with novel technologies. In both countries, cream was the predominant dosage form and imidazoles were the major substance group. Ketoconazole was the lead active substance in Brazil and ciclopirox was the lead drug in the US. Generic products dominated both markets. Despite the great number of registered products, the Brazilian market lacks the latest technologies, reflecting that the ease of generics registration is not accompanied by innovation.

Stability‐indicating analytical method of quantifying spironolactone and canrenone in dermatological formulations and iontophoretic skin permeation experiments

A simple, stability-indicating, chromatographic method of quantifying spironolactone (SPI) and its metabolite, canrenone (CAN), in the presence of excipients typical in dermatological formulations and skin matrices in studies of passive and iontophoretic permeation was proposed and validated here. SPI and CAN were separated using a reversed-phase column with a mobile phase of methanol-water (60:40, v/v) at a flow rate of 1.0 mL/min. Data were collected with a UV detector at 238 and 280 nm, with retention times of 6.2 and 7.9 min for SPI and CAN, respectively. The method was precise, accurate and linear (r2 > 0.99) in a concentration range of 1-30 μg/mL, and recovery rates of SPI and CAN from the different skin layers exceeded 85%. The method was not only sensitive (LOD of 0.05 and 0.375 μg/mL and LOQ of 0.157 and 1.139 μg/mL for SPI and CAN, respectively) but also selective against skin matrices and highly representative components of topical formulations. The method moreover demonstrated SPI's degradation in iontophoresis by applying Pt-AgCl electrodes and its continued drug stability using Ag-AgCl electrodes. Altogether, the method proved valuable for quantifying SPI and CAN and may be applied in developing and controlling the quality of dermatological products.

Allergic contact dermatitis in atopic individuals: Results of a 30-year retrospective study.

The association between atopic dermatitis (AD) and contact allergy, remains unclear, with studies to date showing conflicting results. To investigate the prevalence of contact allergy in AD individuals compared to those without AD. Results of 46 250 patients patch tested in a single centre over a span of 30 years were reviewed, comparing those with AD with those without AD. Collected data were analysed with corrections for multiple confounding variables, including date of patch testing to account for changes in allergens tested over the period. Nine allergens showed a statistically significant difference between the two groups. Contact allergy to nickel, cobalt and primin was less likely to arise in those with AD, whilst substances found in topical dermatological products were more likely to be associated with AD. This is the largest single centre study of contact sensitization in atopy reported to date. The previously reported association between contact allergy to sesquiterpene lactone and AD is reinforced. The decreased incidence of metal allergy suggests distinct immunological effector mechanisms in sensitization to these allergens. In keeping with previous publications, exposure to topical treatments for AD can result in sensitisation and contact allergy and clinicians should consider patch testing in AD individuals who report worsening of their skin despite continued treatment with topical medicaments.

Minimising pain and medical adhesive related skin injuries in vulnerable patients.

The skin is the largest and one of the most important organs of the body and as such it is essential that skin integrity is maintained to preserve normal body functions as much as possible at all times. Health professionals must endeavour to minimise any pain and trauma likely to be encountered by their patients through the use of a variety of medical products and devices that are designed to adhere to the skin, especially as the use of dermatological and wound-management products in particular, that incorporate adhesives to help keep them secure and in place, has grown in line with the increasingly ageing population and changing demographics throughout the UK. This article reviews the literature related to the causes of medical-adhesive-related skin injuries (MARSIs) and the reported patient effects, in particular pain and skin trauma and highlight some 'at-risk' patient groups and potential actions to minimise risk. A sterile silicone medical adhesive remover-Appeel Sterile-is introduced and the clinical benefits highlighted through the discussion of clinical evidence and case studies undertaken on a range of patients with varied aetiologies.

Topical purified omental lipid formulations in the prevention of skin ulcers: a narrative review.

The omentum is a large peritoneal fold. Its main function is to protect abdominal organs, exerting a defensive action against infective agents. The tissue promotes repair after several types of injury. An extensive vascularisation is the key characteristic of this tissue and the omentum has the highest level of production and content of vascular endothelial growth factor (VEGF). A component of omentum is the lipid compound, which carries out important activities for the organism. Omentum is rich in neutral glycerides, phospholipids, glycolipids and gangliosides. Dermatological products containing purified omental lipids are commercially available and topical omental extracts have been useful in the softening, moisturising and smoothing of skin. Animal-derived omental lipids could be use in topical products with different textures (creams, fluids, emulsions and cleansers) and at different concentrations (10-25%) for the treatment of fragile skin or skin conditions causing risk of ulcer formation. This review summarises the pharmacological rationale of purified omental lipids in topical formulations for use in fragile skin conditions, the clinical efficacy data available in the scientific literature and the potential future perspectives. Efficacy of topical purified omental lipids have been demonstrated in numerous clinical controlled trials involving a total of 320 subjects. These studies demonstrated that this product helps prevent the formation of pressure ulcers (PU) in hospitalised high-risk subjects, improves wound healing process, normalises skin hydration in diabetic subjects with moderate-severe skin xerosis and improve the clinical evolution of diabetic foot. Therefore, purified omental lipid could be an effective tool for the management of fragile skin and the skin at high risk of PU formation.

Gender-related cost discrepancies in a cohort of 110 facial moisturizers.

Gender-related price inequalities for over-the-counter dermatologic products such as shampoos and conditioners, razors, deodorants, and lotions remain prevalent in the marketplace. This trend has also been found to apply to topical minoxidil, a common treatment for male and female pattern hair loss. We sought to identify the gender-related price discrepancies of facial moisturizers, which are routinely recommended by dermatologists. Three online retailers (Amazon, Target, and Walmart) were surveyed for available facial moisturizers in October 2018. Facial moisturizers were classified as men's, women's, or gender-neutral based on three specific marketing variables: language, container color/graphics, and container curvature/shape. In total, 110 facial moisturizers were included in this analysis. Of the 54 facial moisturizers evaluated for men, 47 (87%) contained the word "men" within the marketing language, while only three of 56 (5.4%) facial moisturizers targeted at women were explicitly labeled "for women." No statistically significant difference was found between the number of facial moisturizers listed as fragrance-free, SPF-containing, anti-aging, or those labeled as sensitive, hypoallergenic, or dermatologist recommended between the two groups. However, facial moisturizers marketed to women were on average $3.09 more per ounce than those marketed to men. A two-tailed t test revealed a statistically significant difference between the price per ounce of facial moisturizers for men ($6.20) and those for women ($9.29) (P=0.013). Facial moisturizers marketed to women were found to be significantly more expensive than comparable facial moisturizers marketed to men.

Evaluation of anti-melanoma and tyrosinase inhibitory properties of marchantin A, a natural macrocyclic bisbibenzyl isolated from Marchantia species

Macrocyclic bisbibenzyl compound, marchantin A, naturally occurring in liverworts belonging to genus Marchantia, was isolated and assessed for their cytotoxicity against two different lines of human skin cells - immortalized human keratinocytes HaCaT and human malignant melanoma cells A375. The purpose of the studies was also to examine the anti-hyperpigmentation effect of marchantin A, especially used in concentrations assessed as safe to normal human keratinocytes while simultaneously toxic for malignant melanoma cells.The data showed that marchantin A was cytotoxic for A375 melanoma cells (IC50 = 11.97, 7.45 and 9.80 μg/mL), nevertheless less cytotoxic for normal keratinocytes. Assay conducted for mushroom tyrosinase activity showed also that this compound did not affect the dopachrome formation during enzymatic reaction in concentrations previously assessed as safe for normal human cell. To our knowledge this is the first report showing anti-melanoma activity of marchantin A and assessing its activity against tyrosinase. Obtained results indicate potential application of marchantin A as a potential active ingredient for pharmaceutical and dermatological products.

Ascorbic acid derivative-loaded modified aspasomes: formulation, in vitro, ex vivo and clinical evaluation for melasma treatment

Vitamin C (L-Ascorbic acid) has many favourable effects on the skin such as antioxidant, anti-aging and whitening effects. Its instability and low permeability limit its pharmaceutical use in cosmetic and dermatological products. Instead, Mg ascorbyl phosphate (MAP), an ascorbic acid derivative, has the same effect with higher stability is being used. In this work, a vesicular system, aspasomes, containing MAP was developed and evaluated. Aspasomes are multilayered vesicles formed by amphiphiles molecules, Ascorbyl palmitate (ASP), in combination with cholesterol and charged lipids for drug encapsulation. Here, we investigated the use of lecithin instead of the charged lipid dicetyl phosphate for aspasomes development. Nine formulations were prepared and evaluated for their entrapment efficiency, particle size, polydispersity index (PDI) and zeta potential. Their entrapment efficiency ranged from 33.00 ± 2.27 to 95.18 ± 1.06, while their particle size was from 373.34 ± 60.85 to 464.37 ± 93.46 nm with acceptable PDI (from 0.212 ± 0.068 to 0.351 ± 0.061) and zeta potential (from −37.52 ± 2.42 to −50.36 ± 1.82). Three formulations were selected and evaluated for their drug release, permeation and retention into skin. One formulation was selected to be formulated as aspasomal topical cream and gel. The aspasomal cream was found to have enhanced drug permeation and skin retention over the aspasomal gel as well as the aspasomes formulation. MAP aspasomal cream was evaluated clinically as an effective treatment for melasma against 15% trichloroacetic acid (TCA) and the results recorded that the aspasomal cream showed the greatest degree of improvement regarding the hemi-MASI scores with 35% of patients rating it as excellent treatment. The study showed that MAP aspasomal cream can be considered a novel treatment of melasma which is free of side effects. Its efficacy as a monotherapy is superior to that of chemical peeling using 15% TCA.

Use of Advanced Imaging Techniques for the Characterization of Oily Skin.

Excessively oily skin leads to clinical signs that cause discomfort to patients, such as excessive shine, enlarged pores, acne, and an imbalance of the hydrolipidic layer. In this context, a constant demand for the research and development of products that prevent these features, has been noted in the field of cosmetics and dermatology. Thus, the objective of this study is to evaluate the cutaneous characteristics of oily skin due an excessive production of sebum through biophysical and skin imaging techniques. 19 participants with different skin types were selected and the following parameters were evaluated: pore count, determination of the number of sebaceous glands and amount of sebum in infundibulum, determination of cutaneous microrelief, count of comedones, evaluation of epidermis thickness, characterization of the cellular, and comedone size and its characteristics. These evaluations were done through biophysical and skin imaging techniques. The obtained results showed that different regions of the face presented different characteristics related to oiliness, quantity, and the appearance of pores and comedones. The malar region had a lower epidermis thickness and a larger number of large pores. Moreover, in this region excessive sebum production, which can be related to pores, not comedones, was noted. The nose region presented higher sebum content in the infundibulum and lower active sebaceous glands, showing a higher activity of sebaceous production in this region. The chin region presented a positive correlation between the sebum content, roughness parameter and the number of pores and comedones. As different skin properties are related and influence the appearance of undesirable clinical signs, we identified the need for a multifactorial approach for the effective treatment of oily skin. The rational development of multifunctional cosmetic products that promote the control of oily skin, that regulate the keratinization process, improve the microrelief and leads to a better epidermis and dermis structure, will not only improve oily skin conditions but will also allow for the reduction or disappearance of clinical signs that result from excessive oiliness, all of which causes concern and results in a relentless search for cosmetic and dermatological products that address the unaesthetic nature of these conditions.

Repairing Injured Skin: Biologics, Skin Substitutes, and Scaffolds: Review

Context: Skin damage is one of the most common injuries that occur daily for millions around the world. Considering this high prevalence, developing new methods of cells and stem cell administration for healing injured skin is necessary. We discuss different new methods of stem cell and cell administration for repairing injured skin, such as skin stem cell gun, scaffolds, hydrogels, and autologous keratinocytes sheets. Evidence Acquisition: Many approaches are available in injured skin healing, such as traditional therapy, transplanting, cell therapy, and stem cell therapy. Skin grafting is still a standard solution to treat patients; however, there are a lot of limitations in this procedure, for example, patients with severe burns have an insufficient skin area for grafting, which is a painful procedure. Results: Although cell therapy approaches dissolve scarring and reduce healing time, considering its high cost, they are not used in everyday society. This article discusses different regenerative dermatology products and compares them with each other. Conclusions: Herein, we introduced several examples of skin cell products in the pharmaceutics market. Although these products are not well known and even some of them didn’t reach clinical trials, comparing different kinds of skin engineered products reveals appropriate guidelines for their use and entrance to dermatology market.

Anti-Wrinkling and Anti-Melanogenic Effect of Pradosia mutisii Methanol Extract.

Ultraviolet (UV) exposure causes skin photoaging leading to skin wrinkling and sagging via production of reactive oxygen species (ROS). For this reason, protection from photoaging is an important feature in cosmeceutical and dermatological products. Natural product-derived biomaterials are highly desired as future possible ingredients, because these biomaterials are often safe and effective. In this study, we aimed to characterize the skin protective activity of Pradosia mutisii, traditionally used to treat sunburn and erythema. We determined the free radical scavenging, anti-melanogenic, and moisturizing effects of a methanol extract of Pradosia mutisii (Pm-ME) in keratinocytes (HaCaT cells), melanocytes (B16F10 cells), and fibroblasts (human dermal fibroblasts (HDFs)) at non-cytotoxic concentrations. Pradosia mutisii methanol extract contains coumaric acid as a major component, and the extract exhibited protective activity against UVB- and H2O2-induced cytotoxicity. This extract also suppressed the expression of metalloproteinases (MMPs) and cyclooxygenase (COX)-2 in HaCaT cells. A reduction of Sirt-1 expression under UVB- and H2O2-treated conditions was recovered in HaCaT cells by Pm-ME. This extract displayed significant free radical scavenging activity according to the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) assay. The Pm-ME also upregulated the expression levels of hyaluronic acid synthase (HAS) and transglutaminase-1 (TGM-1) in HaCaT cells, indicating a putative moisturizing activity. Interestingly, the expression of collagen type 1 (Col1A1) gene and its promoter activity, as assessed by a reporter gene assay, were found to be increased in HDF and HEK293 cells. Similarly, Pm-ME helped recover collagen levels after UVB and H2O2 treatment in HDFs as well as decreased the synthesis and secretion of melanin from B16F10 melanoma cells, which may indicate a beneficial whitening cosmetic value. The p38 inhibitor SB203580 and the JNK inhibitor SP600125 suppressed MMP-9 and COX-2 expression in H2O2-treated HaCaT cells. Similarly, the ERK inhibitor U0126 inhibited HAS-2 in Pm-ME/H2O2-treated HaCaT cells. These findings suggested that inhibition of JNK and p38 and activation of ERK could be targeted by Pm-ME. Therefore, Pm-ME may exert anti-photoaging and anti-melanogenic properties via the regulation of mitogen-activated protein kinase, which could be beneficial in the cosmeceutical industry.

A Serum Containing Deschampsia antartica Extract, Ferulic Acid and Vitamin C has Anti-Pollutant Effects on Skin Exposed to High Tropospheric Ozone Levels: A Controlled Single-Blind, Prospective Clinical Trial in Women Living in Urbanized, High Air Pollution Area during the Summer Season

Introduction: Air pollution induces skin damage and accelerating skin aging processes, mainly through oxidative stress. Pollutant substances, such as particulate matter (PM10, PM2.5) and tropospheric ozone (O3), can activate specific intracellular receptors called AhR (Aryl-Hydrocarbon Receptors) and this activation is involved in the skin aging process. Deschampsia antartica aqueous extract (DAE) has shown, in vitro, to reduce the pollutant-induced AhR activation. Ferulic acid (FA) and vitamin C (VC) are well known potent anti-oxidant substances. A dermatological product in serum formulation containing DAE/FA/VC has been recently commercialized. This product has demonstrated in vivo to protect skin from pollution damage during winter season when PM10 levels are very high. No data have been published so far regarding the protective effect of this serum during summer months when the main atmospheric pollutant is O3. Objective and materials and methods: We carried out a prospective, single-blind, controlled 28-day study during the summer season (characterized by elevated O3 tropospheric levels) in 20, photo type II-III, women (mean age 38 years) with mild-moderate skin aging, living in an urbanized, high pollution area (City of Rome) compelling to spend at least 2 hours daily outdoor. The study’s outcomes were to evaluate the effects of treatment on skin barrier function, assessed by TEWL measurement (Tewameter) and corneometry, skin appearance by high resolution photographs with Visioface Quick (Courage and Khazaka) and the effect on squalene peroxide (SQOOH)/squalene (SQ) skin ratio measured with face swabs. Results: The trial was conducted between July the first, and August 2, 2019. All the subjects concluded the trial. During the study period, elevated O3 concentration (>120 microg/m3) were registered in 22 out of 31 days (71%) (The ARPA official database, Agenzia regionale per la protezione ambientale). The product induced, in comparison with baseline values, a significant improvement of skin barrier function and hydration (-14% of TEWL and +16% skin hydration), significant improvements in skin appearance and SQOOH/SQ ratio (-19%) were also observed. The 90% of the subjects involved in the trial evaluated the product very well regarding cosmetic acceptability. Discussion: The results of the present study has demonstrated that a serum containing DAE/FA/VC can improve skin barrier function, skin appearance and counteract skin oxidative stress in women living in high O3 pollution urban area during the summer period.

Chromatographic Estimation of Niacinamide in Anti aging Dermatological product

In this study Niacinamide based skin creams were formulated and evaluated. Niacinamide (also known as nicotinamide, 3-pyridinecarboxamide) is the physiologically active form of niacin or vitamin B3. Niacinamide, a derivative of niacin, has the ability to treat some skin conditions including aging skin. Quality evaluation of the product was assessed by using determination of Niacinamide content by HPTLC method and different evaluation methods. No change of the physical properties was observed; the pH was in a proper range. The formulations showed good spreadability, no evidence of phase separation and good consistency during this study period. From the present study it can be concluded that it is possible to develop creams containing Niacinamide having antiaging property and can be used as the provision of a barrier to protect skin.

Wound Healing Effect of Essential Oil Extracted from Eugenia dysenterica DC (Myrtaceae) Leaves.

The use of natural oils in topical pharmaceutical preparations has usually presented safe agents for the improvement of human health. Based on research into the immense potential of wound management and healing, we aimed to validate the use of topical natural products by studying the ability of the essential oil of Eugenia dysenterica DC leaves (oEd) to stimulate in vitro skin cell migration. Skin cytotoxicity was evaluated using a fibroblast cell line (L929) by MTT assay. The oil chemical profile was investigated by GC-MS. Moreover, the inhibition of lipopolysaccharide (LPS) induced nitric oxide (NO) production in the macrophage cell line (RAW 264.7) tested. The Chick Chorioallantoic Membrane (CAM) assay was used to evaluate the angiogenic activity and irritating potential of the oil. The oEd induces skin cell migration in a scratch assay at a concentration of 542.2 µg/mL. α-humulene and β-caryophyllene, the major compounds of this oil, as determined by GC-MS, may partly explain the migration effect. The inhibition of nitric oxide by oEd and α-humulene suggested an anti-inflammatory effect. The CAM assay showed that treatment with oEd ≤ 292 µg/mL did not cause skin injury, and that it can promote angiogenesis in vivo. Hence, these results indicate the feasibility of the essential oil of Eugenia dysenterica DC leaves to developed dermatological products capable of helping the body to repair damaged tissue.

The study of the assorment of dermatological products for the local treatment of seborrheic dermatitis

Aim. To perform the analysis of the assortment of medicines, in particular dermatological agents for the treatment of seborrheic dermatitis, which are present at the domestic pharmaceutical market with the subsequent substantiation of the need to develop a new foaming agent.Materials and methods. The analysis was based on the data of the State Register of Medicinal Products of Ukraine, electronic databases, “Morion” information retrieval program. The logical, system-analytical, comparative methods of analysis were used in the work.Results. The analysis of the drugs belonging to D01A group “Antifungal preparations for topical administration”, namely the subgroups: D01A C – “Imidazole and triazole derivatives” and D01A E – “Other antifungal agents for topical application” registered at the Ukrainian market has shown that the leading positions are in the subgroup D01A C – “Imidazole and triazole derivatives” (71 %), while the group D01A E – “Other antifungal agents for topical application” has only 29 %. It has been found that the composition of the drugs studied includes 8 synthetic active substances. Derivatives of imidazole, pyrithione, allylamines are the most frequently used. It has been determined that among these medicines monopreparations predominate; some of them are 88 % of the total number of trade names, while only 12 % are combined drugs. Further study of the assortment of the registered producers of antifungal agents for local application by manufacturing countries has shown that 13 countries are registered at the Ukrainian market: India (35 %), Ukraine (32 %), Switzerland (6 %), Belgium, Germany and Turkey (4 %), Spain and Belgium (3 % each). All other manufacturing countries are represented by 2 %. It has been noted that the soft dosage form predominates in the structure of the drugs under study, namely creams – 41 %, ointments – 12 %, gels – 15 %; liquid forms are shampoos – 16 %, solutions for external use – 8 %, spray – 6 %; and there are only 2 % of solids.Conclusions. Based on the data of the State Register of Medicinal Products of Ukraine it has been found that the total number of drugs of group D01A “Antifungal preparations for topical administration” is 51 trade names. It has been noted that 8 active substances of synthetic origin are presented in the form of monopreparations (88 %) or in combination (12 %) with each other. It has been found that the ratio between imported and domestic medicines is 68 %: 32 %. It has been determined that 41 % of the drugs registered are produced in the form of a cream, 16 % in the form of a shampoo, 15 % in the form of a gel and 12 % in the form of an ointment, while a small part of the preparations is in the form of a solution, a spray and a powder.

An updated review of clinical methods in the assessment of ageing skin - New perspectives and evaluation for claims support.

With the advancement of skin research, today's consumer has increased access to an informed understanding of ageing skin and its appendages, together with a plethora of targeted products to meet such needs. In recent years, increased legislative demands for quality evidential claims support have led not only to the development and validation of clinical methods to measure and quantify ageing skin, but also a clearer understanding of the skin ageing process-especially the impact of both its internal and external environments-as well as a tougher stance on clearly unjustifiable claims. Traditional testing methods used to research and evaluate anti-ageing products claim to employ sophisticated instruments. Today, however, since the term anti-ageing can be considered a misnomer, intelligent use of combined more advanced clinical methods has enabled the development of technologically improved consumer products providing enhanced efficacy and targeted performance. Non-invasive methods for the assessment and quantification of the causes of ageing skin provide tools to the clinical researcher as defined by key clinically observed ageing parameters. Where evidence requires additional support, a number of clinical procedures evaluating ageing skin and hair products are combined with invasive procedures, thus enabling an added value to product claims. As discussed herein, given the enhanced understanding of ageing, we provide an update to our previous reviews of clinical methods used in the assessment of skin ageing, to include the wider aspects of environmental exposure; skin pigmentation; microbiome disturbance; surface topography; colour, radiance, and pH; and structural integrity-all requiring a disciplined approach to their use in dermatological investigations and product claims evidence.

Solvent-Extracted Wool Wax: Thermotropic Properties and Skin Efficacy

Background/Aims: Wool wax is a soft, yellow, waxy substance that is secreted by the sebaceous glands of sheep. The purpose of wool wax is to waterproof and protect the wool. Chemically, wool wax is a complex mixture of esters, fatty acids, and alcohols. Wool waxes with different prop­erties can be obtained by following different extraction methodologies. Methods: Two differently extracted wool waxes are compared in this study. Their effectiveness in mimicking the properties of skin lipids is evaluated. In addition, the lipid compositions and thermotropic behaviours of the 2 differently extracted wool waxes were evaluated. Results: The solvent-extracted wool wax was found to have a significantly higher polar lipid content than that of the water-extracted wool wax. This increase in the polar character of the solvent-extracted wool wax was also demonstrated by increased values of transition and degradation temperatures in the differential scanning calorimetry and thermogravimetric analyses, respectively. In addition, solvent-extracted wool wax demonstrated the ability to reinforce stratum corneum lipids, which led to improved skin barrier function. Conclusions: The suitability of the solvent-extracted wool wax for application in the preparation of cosmetics and dermatological products was demonstrated.

658 In vivo confocal Raman spectroscopy and chemometric analysis on human stratum corneum: Insights on composition, organization, aging and photoaging

Aging and photoaging have significant negative impact on skin barrier function; weakening the protective barrier of the body against water loss, toxic agents and microorganisms. To understand the condition of the barrier for cosmetic and pharmaceutical research it is valuable to characterize the stratum corneum (SC) at a molecular level. Confocal Raman spectroscopy allows in vivo, non-invasive, and depth resolved investigation of human skin. This advanced technique enables chemical and structural information at a molecular level and high spatial resolution in the low micrometer scale. These advantages have made Raman spectroscopy one of the tools at the forefront of dermatological research, generating a rapidly increasing number of research applications. However, the Raman spectrum of human SC is complex and a complete assignment of the contributions from the various skin constituents is not currently available. Similarly, effects of aging and photoaging havent been fully characterized with this technique. In this work, we combine in vivo confocal Raman spectroscopy and chemometric analysis to identify the contribution of the primary skin constituents to the Raman spectrum of human SC and describe the composition and organization of the SC. We also quantify several metrics of skin barrier quality in young and older populations, including lipid to protein ratio, SC thickness and water content, and evaluate effects related to aging and photoaging. Using this approach, we have obtained molecular scale information about the composition, organization and barrier function of the SC. This information is a critical driver for breakthrough innovations that will impact dermatological research and product development.

Photodamage attenuating potential of Nectandra hihua against UVB-induced oxidative stress in L929 fibroblasts

The total phenolic content (TP) and antioxidant activity of the ethanolic extract and fractions that were obtained from the leaves of Nectandra hihua were assessed using different methods. The ethanolic extract (EE) and ethyl acetate fraction (EAF) had the best antioxidant capacity, which was comparable to butylated hydroxytoluene and quercetin (ABTS+ 2.55 ± 0.06, 3.54 ± 0.03 mmol TE/g; DPPH IC50 10.27 ± 0.05, 9.88 ± 0.02 μg/mL; FRAP 2.17 ± 0.08, 2.38 ± 0.04 mmol TE/g; ORAC 5.16 ± 0.08, 5.35 ± 0.07 mmol TE/g; TP 568.05 ± 18.15, 397.20 ± 17.88 mg GAE/g, respectively). The cytoprotective effect, reactive oxygen species (ROS) and lipid peroxidation inhibitions on L929 fibroblasts irradiated with UVB (600 mJ/cm2) in pre- and post-treatments with EE and EAF were determined. These plant materials demonstrated high ROS scavenging activity and lipid peroxidation inhibition on L929 fibroblasts in both treatments, especially with pre-treatment (EE 38.47 ± 1.95% and EAF 40.20 ± 4.5% inhibition of ROS production, and EE 39.03 ± 3.33% and EAF 41.67 ± 7.6% of lipid peroxidation inhibition), indicating the best cytoprotection with pre-treatment (13.52 ± 1.66% and 13.34 ± 2.61% increases in cell viability). The antioxidant flavonoids quercitrin, avicularin, juglalin, afzelin and astragalin were isolated from EAF. The results obtained indicate that EE and EAF present photodamage attenuating potential against UVB-induced oxidative stress and can be useful as a starting point for developing dermatological products to prevent oxidative skin damage.