Skin moisturization mechanisms: new data

Lespedeza maximowiczii flower absolute promotes skin epithelization, barrier properties, and moisturization-related beneficial responses in human keratinocytes

Lespedeza maximowiczii (LM), a member of the legume family, has tyrosinase inhibitory and estrogenic activities. However, its effects on skin-related biological activities remain unclear. Therefore, the present study aimed to explore the effects of LM flower absolute (LMFAb) on skin-related biological events, especially skin re-epithelization, barrier and moisturizing-related keratinocyte (HaCaT cell) responses. In this study, LMFAb was isolated from LM flowers via solvent extraction and its chemical composition analysis was performed using gas chromatography/mass spectrometry. 5-bromo-2'-deoxyuridine incorporation, Boyden chamber, sprout outgrowth, enzyme-linked immunosorbent, and Western blot assay were used to analyze the biological effects of LMFAb on HaCaT cells (a human epidermal keratinocyte cell line). Twelve components were identified in LMFAb. LMFAb promoted cell proliferation, migration, and sprout outgrowth in HaCaT cells. The absolute enhanced the activations of MAPKs (ERK1/2, JNK, and p38), PI3K and AKT proteins in HaCaT cells and elevated collagen type I and IV levels in HaCaT cell conditioned medium. In addition, LMFAb induced an increase in the expression levels of epidermal barrier proteins (filaggrin and involucrin) in HaCaT cells. Furthermore, LMFAb increased hyaluronan (HA) production and expression of HA synthases (HAS-1, HAS-2, and HAS-3) but decreased HYBID (HA binding protein involved in HA depolymerization) level in HaCaT cells. These findings demonstrate that LMFAb might promote skin re-epithelization, barrier and moisturizing-related beneficial responses in keratinocytes. This study suggests that LMFAb should be considered a potential starting material for the development of cosmetic or pharmaceutical agents that restore the functions of damaged skin.

Ameliorative effect of black tea extract on the skin of D-galactose-induced aging mice

Aging is a universal and irreversible process, and the skin is an important feature that reflects the aging of the organism. Skin aging has been a focus of attention in recent years because it leads to changes in an individual's external features and the loss of many important biological functions. This experiment investigated the improvement effect of black tea extract (BTE) on the skin of aging mice under D-galactose induction. After 6 weeks of administration, the changes in skin bio-chemical indices and tissue structure were compared with the blank and positive control groups. It was observed that BTE increased water and hyaluronic acid (HA) content, decreased malondialdehyde (MDA) content, enhanced superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in the skin of aging mice, and improved the structure of aging damaged skin tissues and increased the content of total collagen. The experimental results showed that BTE can play a significant anti-aging effect on the skin, which can be used as a functional food for aging inhibition.

Natural products in cosmetics

The global cosmetics market reached US$500 billion in 2017 and is expected to exceed US$800 billion by 2023, at around a 7% annual growth rate. The cosmetics industry is emerging as one of the fastest-growing industries of the past decade. Data shows that the Chinese cosmetics market was US$60 billion in 2021. It is expected to be the world's number one consumer cosmetics market by 2050, with a size of approximately US$450 billion. The influence of social media and the internet has raised awareness of the risks associated with the usage of many chemicals in cosmetics and the health benefits of natural products derived from plants and other natural resources. As a result, the cosmetic industry is now paying more attention to natural products. The present review focus on the possible applications of natural products from various biological sources in skin care cosmetics, including topical care products, fragrances, moisturizers, UV protective, and anti-wrinkle products. In addition, the mechanisms of targets for evaluation of active ingredients in cosmetics and the possible benefits of these bioactive compounds in rejuvenation and health, and their potential role in cosmetics are also discussed.

Glycerol fermentation by skin bacteria generates lactic acid and upregulates the expression levels of genes associated with the skin barrier function

Commensal bacteria play a major role in multiple skin functions by providing the first layer of defense against pathogens and maintaining the skin barrier. Staphylococcus epidermidis is one of the most common skin commensals. In this study, we showed that S. epidermidis ferments glycerol and uses it as a nutrient, while producing short-chain and organic fatty acids, with the most notable being lactic acid. Lactic acid is an alpha-hydroxy acid that inhibits the growth of pathogenic bacteria, without any negative effect on the commensal bacteria itself. Using in vivo experiments, we validated our in vitro results, showing that the skin microbiome is also capable of doing this. Finally, using 2D and 3D skin culture models, we showed that the fermentation of glycerol, mainly lactic acid, as determined by analytical methods, upregulates the expression levels of several key genes that are associated with the barrier properties of the skin. While the hydration effect of glycerol on the skin is well known, our study shows the overall benefits of glycerol on the skin microbiome, while revealing an alternate mode of action of glycerol for multiple skin benefits.

Evaluation of Cosmetic and Dermatological Properties of Kombucha-Fermented Berry Leaf Extracts Considered to Be By-Products

Leaves of Rubus fruticosus L., Vaccinum myrtillus L., Ribes nigrum L. and Fragaria vesca L. are considered agro-waste of the berry industry, but they can be a rich source of valuable bioactive compounds used in cosmetic industry. In this study, kombucha-fermented and non-fermented extracts were compared in terms of chemical composition and biological activity. Polyphenol compounds were identified by HPLC/DAD/ESI-MS. The antioxidant potential was analyzed by evaluating the scavenging of intracellular free radicals contained in keratinocytes and fibroblasts and by DPPH and ABTS assay, obtaining a higher radical scavenging capacity for the ferments, especially for R. fruticosus and V. myrtillus ferments. Assessment of the cytotoxicity on skin cell lines showed their positive effect on the viability of fibroblasts and keratinocytes (especially for the ferments after 10 days of fermentation). The potential anti-ageing properties were determined by their ability to inhibit the activity of metalloproteinases, obtaining almost 30% inhibition of collagenase and elastase in the case of fermented V. myrtillus. Moreover, when the samples were applied to the skin, the positive effect of ferments on skin hydration and pH was demonstrated, which indicates that kombucha berry leaf extracts may be an innovative cosmetic ingredient.

Preparation, characterization, and application of polysaccharide-based emulsions incorporated with lavender essential oil for skin-friendly cellulosic support

This study aimed to develop polysaccharide-based emulsions incorporated with lavender essential oil and their application on cellulosic support for patches obtaining. The lavender essential oil has been added to emulsions as an active compound mainly due to its antimicrobial properties. In this study, emulsions were used to deliver active ingredients (lavender essential oil). The chemical composition of essential oil was analyzed using gas chromatography-mass spectrometry (GC/MS). A total of seven emulsions (RiACL) were evaluated by determining rheological parameters and microbiological analysis. One of the emulsions (R7ACL) was applied to cellulosic support to obtain non-irritating textiles with controlled release of the active compound and moisturizing effects. Obtained cellulosic support was analyzed in terms of active compound controlled release, toxicity and antimicrobial testing, and skin analysis in healthy volunteers. It was found that the cellulosic supports treated with O/W emulsions are non-irritating, have softness and moisturizing effects, and can be used safely in topical applications for patches obtaining.

Antioxidant and Cytoprotective Properties of Plant Extract from Dry Flowers as Functional Dyes for Cosmetic Products

Nowadays, natural dyes are expected by the cosmetic and food industries. In contrast to synthetic dyes, colorants derived from natural sources are more environmentally friendly and safer for human health. In this work, plant extracts from Gomphrena globasa L., Clitoria ternatea L., Carthamus tinctorius L., Punica granatum L. and Papaver rhoeas L. as the natural and functional dyes for the cosmetics industry were assessed. Cytotoxicity on keratinocyte and fibroblast cell lines was determined as well as antioxidant and anti-aging properties by determining their ability to inhibit the activity of collagenase and elastase enzymes. In addition, the composition of the extracts was determined. The obtained extracts were also applied in face cream formulation and color analyses were performed. It has been shown that the obtained extracts were characterized by no cytotoxicity and a high antioxidant potential. The extracts also show strong ability to inhibit the activity of collagenase and moderate ability to inhibit elastase and provide effective and long-lasting hydration after their application on the skin. Application analyses showed that the extracts of P. rhoeas L., C. ternatea L. and C. tinctorius L. can be used as effective cosmetic dyes that allow for attainment of an intense and stable color during the storage of the product. The extracts of P. granatum L. and G. globasa L., despite their beneficial effects as active ingredients, did not work effectively as cosmetic dyes, because cosmetic emulsions with these extracts did not differ significantly in color from emulsions without the extract.

Hyaluronic acid (HA) stimulates the in vitro expression of CD44 proteins but not HAS1 proteins in normal human epidermal keratinocytes (NHEKs) and is HA molecular weight dependent

BACKGROUND

In the skin, hyaluronic acid is broken down to smaller fragments by hyaluronidase enzymes, particularly when skin is wounded. The impact of various molecular weight fragments of HA on normal human epidermal keratinocytes (NHEK) with regard to expression of important cellular proteins has not been deeply explored.

AIMS

Examination of three molecular weight (Mw) fractions of hyaluronic acid: 1) average Mw of the high fraction: 1.5-2 MDa, 2) average Mw of the medium fraction: 200-500 kDa, and 3) average Mw of the low fraction: 5-10 kDa and a unique 1:1:1 composite complex of the three HA fragments (Triluronic^® Acid) was done to examine the influence of the HA on two critical skin cell protein targets: hyaluronan synthase-1 (HAS-1) and the HA binding protein cluster of differentiation 44 (CD44).

METHODS

NHEKs were treated in vitro with a 1.0% stock solution of each HA Mw fraction at 1.0, 0.5, and 0.1% concentrations of the 1.0% solution and the polysaccharide composite at the same concentrations for 48 Hrs. The cells were than analyzed by ELISA protein assays for HAS-1 and CD44 protein content.

RESULTS

Examination of HAS-1 protein expression indicates that none of the HA test materials influenced the expression of HAS-1 at any concentration. Examination of the CD44 protein expression indicated that the low Mw fraction and the commercial complex of the three Mw fractions upregulated CD44 protein expression in NHEKs, but the medium Mw and high Mw HA fractions did not.

CONCLUSIONS

In this work, it was demonstrated that HA can influence the expression of CD44 protein, a critical HA transmembrane HA binding protein, and the influence appears to be molecular weight dependent.

Isolation of Industrial Important Bioactive Compounds from Microalgae

Microalgae are known as a rich source of bioactive compounds which exhibit different biological activities. Increased demand for sustainable biomass for production of important bioactive components with various potential especially therapeutic applications has resulted in noticeable interest in algae. Utilisation of microalgae in multiple scopes has been growing in various industries ranging from harnessing renewable energy to exploitation of high-value products. The focuses of this review are on production and the use of value-added components obtained from microalgae with current and potential application in the pharmaceutical, nutraceutical, cosmeceutical, energy and agri-food industries, as well as for bioremediation. Moreover, this work discusses the advantage, potential new beneficial strains, applications, limitations, research gaps and future prospect of microalgae in industry.

Optimization of Ultrasound-Assisted Emulsification of Emollient Nanoemulsions of Seed Oil of Passiflora edulis var. edulis

Passiflora edulis var. edulis is a plant of commercial interest because of it fruits. The seeds, a by-product in the food industry, can be a source of oil for cosmetic, pharmaceutical and food industries. The aims of this work were to optimize the ultrasonic-assisted emulsification conditions for o/w nanoemulsions and to evaluate the emollient activity of the seed oil. The optimum emulsification conditions were established, using the response surface methodology with a Box-Behnken design (BBD). The emollient activity of seed oil of P. edulis var. edulis was evaluated with healthy volunteers using a cutometer for skin moisture and viscoelasticity measurements. The optimal formulation variables (85.34 W of ultrasonic power, 5.96 irradiation time, 70.65% water and a 5:4 oil:surfactant ratio), resulted in considerable improvement in the properties of the ultrasonically formulated nanoemulsions. Finally, the seed oil of P. edulis var. edulis and the nanoemulsion generated by ultrasound presented emollient activity.

Microbial Biosurfactants in Cosmetic and Personal Skincare Pharmaceutical Formulations

Cosmetic and personal care products are globally used and often applied directly on the human skin. According to a recent survey in Europe, the market value of cosmetic and personal care products in Western Europe reached about 84 billion euros in 2018 and are predicted to increase by approximately 6% by the end of 2020. With these significant sums of money spent annually on cosmetic and personal care products, along with chemical surfactants being the main ingredient in a number of their formulations, of which many have been reported to have the potential to cause detrimental effects such as allergic reactions and skin irritations to the human skin; hence, the need for the replacement of chemical surfactants with other compounds that would have less or no negative effects on skin health. Biosurfactants (surfactants of biological origin) have exhibited great potential such as lower toxicity, skin compatibility, protection and surface moisturizing effects which are key components for an effective skincare routine. This review discusses the antimicrobial, skin surface moisturizing and low toxicity properties of glycolipid and lipopeptide biosurfactants which could make them suitable substitutes for chemical surfactants in current cosmetic and personal skincare pharmaceutical formulations. Finally, we discuss some challenges and possible solutions for biosurfactant applications.

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.

Enigmatic Microalgae from Aeroterrestrial and Extreme Habitats in Cosmetics: The Potential of the Untapped Natural Sources

With the increasing demand for natural and safe products in cosmetics, algae with their diverse and valuable bioactive compounds are gaining vital importance. Until now, cosmetics have focused mainly on the use of freshwater and marine algae. However, algae are not restricted to aquatic habitats. They are found in essentially every type of aeroterrestrial and extreme environment on the Earth. There, they have to cope with harsh ecological conditions and have developed special strategies to thrive in these inimical habitats. Although not thoroughly studied, their adaptations include protective biochemical compounds which can find their application or are already used in the field of cosmetics. With proper cultivation techniques, algae from these habitats can provide novel sources of high-value functional products for the cosmetics industry, which have the advantage of being obtained in eco-friendly and cost-effective processes. However, it has to be considered that a few aeroterrestrial and extremophilic algae can be toxin producers, and in order to ensure conformity to the safe quality standards, all new ingredients must be properly tested. The aim of the present review is to unveil the hidden and underestimated potential of the enigmatic algae of aeroterrestrial and extreme habitats for the rapidly developing modern cosmetic industries.

In vitro and in vivo evaluation of a moisture treatment cream containing three critical elements of natural skin moisturization

Objectives

To evaluate skin barrier and hydration effects of a new rebalancing moisture treatment (TRMT) and to assess efficacy and tolerability in subjects with photodamaged skin.

Methods

In an epidermal skin model, tissues (n = 5/group) were topically treated with 25 µL of TRMT, 25 µL of a market‐leading moisturizer (MLM), or untreated for 60 minutes. Hydration was measured at 0, 15, and 30 minutes. Tissues were harvested for gene expression analysis of markers associated with skin barrier and hydration: Claudin (CLD), Aquaporin (AQP), Hyaluronic Acid Syntheses (HAS), and Hyaluronidase (HYAL). A clinical study evaluated twice‐daily application of TRMT, assessing changes in fine lines/wrinkles, brightness, texture, erythema, and tolerability from baseline through week 8. Hydration was measured using electrical impedance.

Results

TRMT and MLM demonstrated significant increases in hydration vs untreated tissue at each timepoint (P < .005), with greater hydration effects observed for TRMT vs MLM. TRMT‐treated tissues demonstrated greater expression of CLD, AQP, and HA, and reduced expression of HYAL vs untreated and MLM‐treated tissues. Twice‐daily application of TRMT demonstrated significant improvements at 2 weeks in fine lines/wrinkles (P < .001), brightness (P < .0001), texture (P < .0004), and hydration (P < .004). At 8 weeks, statistically significant improvements were achieved in all categories.

Conclusion

In an epidermal skin model, TRMT demonstrated significant increases in hydration, greater hydration effects, and expression of key markers associated with skin barrier and hydration vs a MLM. Twice‐daily application of TRMT was well tolerated and resulted in early, significant improvements in hydration and visible improvements in skin brightness, texture, fine lines/wrinkles, and erythema at 8 weeks.

Propionibacterium acnes related anti-inflammation and skin hydration activities of madecassoside, a pentacyclic triterpene saponin from Centella asiatica

Madecassoside is a major pentacyclic triterpene saponin from Centella asiatica with multiple pharmaceutical activities. In this study, we focused on its Propionibacterium acnes related anti-inflammation and skin hydration activities, both of which play important roles in skin homeostasis and barrier function. Madecassoside significantly inhibited the pro-inflammatory cytokine IL-1β, TLR2 and nuclear translocation of NF-κB in P. acnes stimulated THP-1 human monocytic cells. In addition, madecasssoside exhibited significant effects on enhancement of skin hydration through increasing the key moisturizing contributors of aquaporin-3, loricrin and involucrin in HaCaT keratinocytes as well as hyaluronan (HA) secretion in human dermal fibroblasts. The upregulation of HA synthases (HAS1, HAS2, HAS3) and inhibition to ROS formation accounted for the increment of HA content. Together, the in vitro study implied the potential medical and cosmetic application of madecassoside in skin protection.

Multivalent and multifunctional polysaccharide-based particles for controlled receptor recognition

Polysaccharides represent a versatile class of building blocks that are used in macromolecular design. By choosing the appropriate saccharide block, various physico-chemical and biological properties can be introduced both at the level of the polymer chains and the resulting self-assembled nanostructures. Here, we synthetized amphiphilic diblock copolymers combining a hydrophobic and helical poly(γ-benzyl-L-glutamate) PBLG and two polysaccharides, namely hyaluronic acid (HA) and laminarin (LAM). The copolymers could self-assemble to form particles in water by nanoprecipitation. In addition, hybrid particles containing both HA and LAM in different ratios were obtained by co-nanoprecipitation of the two copolymers. By controlling the self-assembly process, five particle samples with different morphologies and compositions were developed. The interaction between the particles and biologically relevant proteins for HA and LAM, namely CD44 and Dectin-1 respectively, was evaluated by surface plasmon resonance (SPR). We demonstrated that the particle-protein interaction could be modulated by the particle structure and composition. It is therefore suggested that this method based on nanoprecipitation is a practical and versatile way to obtain particles with controllable interactions with proteins, hence with the appropriate biological properties for biomedical applications such as drug delivery.

Aquatide Activation of SIRT1 Reduces Cellular Senescence through a SIRT1-FOXO1-Autophagy Axis

Ultraviolet (UV) irradiation is a relevant environment factor to induce cellular senescence and photoaging. Both autophagy- and silent information regulator T1 (SIRT1)-dependent pathways are critical cellular processes of not only maintaining normal cellular functions, but also protecting cellular senescence in skin exposed to UV irradiation. In the present studies, we investigated whether modulation of autophagy induction using a novel synthetic SIRT1 activator, heptasodium hexacarboxymethyl dipeptide-12 (named as Aquatide), suppresses the UVB irradiation-induced skin aging. Treatment with Aquatide directly activates SIRT1 and stimulates autophagy induction in cultured human dermal fibroblasts. Next, we found that Aquatide-mediated activation of SIRT1 increases autophagy induction via deacetylation of forkhead box class O (FOXO) 1. Finally, UVB irradiation-induced cellular senescence measured by SA-β-gal staining was significantly decreased in cells treated with Aquatide in parallel to occurring SIRT1 activation-dependent autophagy. Together, Aquatide modulates autophagy through SIRT1 activation, contributing to suppression of skin aging caused by UV irradiation.

Oral Administration of Glycine and Leucine Dipeptides Improves Skin Hydration and Elasticity in UVB-Irradiated Hairless Mice

Placenta is a special organ that contains many nutrients such as growth factors, minerals, and bioactive peptides. Dipeptides of glycine and leucine are major components of porcine placenta extracts (PPE) that has been used as an alternative of human placenta extracts. In this study, we investigated whether major peptides of PPE, Glycyl-L-Leucine (Gly-Leu), L-Leucyl-Glycine (Leu-Gly), and L-Leucyl-L-Leucine (Leu-Leu), affect skin hydration and elasticity in vitro and in vivo. We found that Gly-Leu and Leu-Gly dipeptides induced the expression of transglutaminase 1 in normal human epidermal keratinocytes (NHEKs) whereas Leu-Leu dipeptides did not. Treatment with Gly-Leu or Leu-Gly significantly increased hyaluronan (HA) synthesis in NHEKs and the upregulation of hyaluronan synthase 2 (HAS2) mRNA level was confirmed. In addition, elastase activity was inhibited in NHEKs treated with Gly-Leu or Leu-Gly dipeptides. Oral administration of Gly-Leu or Leu-Gly dipeptides increased skin hydration and elasticity in UVB-irradiated hairless mice. The significant upregulation of HA in UVB-irradiated hairless mice was observed in response to oral administration of Gly-Leu or Leu-Gly. These results suggest that the major dipeptides of porcine placenta, Gly-Leu and Leu-Gly, are potentially active ingredients for skin moisturization formulations.

A population-based study of the stratum corneum moisture

BACKGROUND

The stratum corneum (SC) has important functions as a bound-water modulator and a primary barrier of the human skin from the external environment. However, no large epidemiological study has quantified the relative importance of different exposures with regard to these functional properties. In this study, we have studied a large sample of individuals from the Brazilian population in order to understand the different relationships between the properties of SC and a number of demographic and self-perceived variables.

METHODS

One thousand three hundred and thirty-nine individuals from a rural Brazilian population, who were participants of a family-based study, were submitted to a cross-sectional examination of the SC moisture by capacitance using the Corneometer® CM820 and investigated regarding environmental exposures, cosmetic use, and other physiological and epidemiological measurements. Self-perception-scaled questions about skin conditions were also applied.

RESULTS

We found significant associations between SC moisture and sex, age, high sun exposure, and sunscreen use frequency (P<0.025). In specific studied sites, self-reported race and obesity were also found to show significant effects. Dry skin self-perception was also found to be highly correlated with the objective measurement of the skin. Other environmental effects on SC moisture are also reported.

Safety and efficacy of Sclerocarya birrea (A.Rich.) Hochst (Marula) oil: A clinical perspective

ETHNOPHARMACOLOGICAL RELEVANCE

Sclerocarya birrea (A.Rich.) Hochst (Marula) nut oil is a popular ingredient in cosmetics such as skin lotions, lipsticks and foundations. The demand for this African oil increased tremendously such that in 2008 almost US$ 20 million was spent on Marula oil for cosmetic product manufacturing. The ethnobotanical literature states that the Zulu people in South Africa amongst others applied the oil to maintain a healthy skin. Scientific studies to support the traditional use as well as the inclusion of Marula oil in cosmetic products is lacking. This study evaluated the irritancy potential (safety), the moisturising and hydrating effects as well occlusivity properties (efficacy) of Marula oil after topical application. In addition, the Marula oil used in this study was comprehensively characterised using two-dimensional gas chromatography coupled to mass spectrometry.

METHODS AND MATERIALS

Quantification of the fatty acid methyl esters (FAMEs) was done using a LECO Pegasus 4D GC × GC-MS. To determine the safety and efficacy of Marula oil healthy caucasian adult female volunteers (n = 20) who complied with the inclusion and exclusion criteria for the irritancy patch, moisture efficacy, hydrating and occlusivity tests were recruited for each study. A 2 × magnifying lamp (visual observation), Chromameter®, Aquaflux® and Corneometer® instruments were used to evaluate and monitor the irritancy level, skin barrier function, transepidermal water loss, hydrating and occlusive effects of topically applied Marula oil.

RESULTS

The GC × GC-MS analysis identified several saturated as well as unsaturated fatty acids. Oleic acid was the major fatty acid constituting 69.0% of the oil followed by palmitic acid (15.3%), linoleic acid (9.2%), palmitoleic acid (4.1%) and stearic acid (1.5%). The clinical study revealed that Marula oil is non-irritant (p < 0.001), with moisturising and hydrating properties (p < 0.001) when applied to a lipid-dry (xerosis) skin. Additionally the oil exhibited occlusive effects (p < 0.001) when applied to normal skin. These findings may be linked to the absorption of the oil into the skin due to the high percentage of oleic acid and the presence of palmitic acid which are known to disturb the stratum corneum intercellular lipids. These fatty acids present in Marula oil are very similar to those present in the epidermis, and can be considered biomimetic.

CONCLUSIONS

Marula oil rich in fatty acids exhibits moisturising, hydrating and occlusive properties. As the oil is non-irritating and provides a moisturising effect with moderate prevention of transepidermal water loss, average moisture retention properties and noteworthy occlusive effects, its inclusion in cosmetic products based on its traditional use may be justified depending on the application.

Exploring the potential of using algae in cosmetics

The applications of microalgae in cosmetic products have recently received more attention in the treatment of skin problems, such as aging, tanning and pigment disorders. There are also potential uses in the areas of anti-aging, skin-whitening, and pigmentation reduction products. While algae species have already been used in some cosmetic formulations, such as moisturizing and thickening agents, algae remain largely untapped as an asset in this industry due to an apparent lack of utility as a primary active ingredient. This review article focuses on integrating studies on algae pertinent to skin health and beauty, with the purpose of identifying serviceable algae functions in practical cosmetic uses.

Production and characterization of cosmetic nanoemulsions containing Opuntia ficus-indica (L.) mill extract as moisturizing agent

This study aimed to produce and characterize an oil in water (O/W) nanoemulsion containing Opuntia ficus-indica (L.) Mill hydroglycolic extract, as well as evaluate its preliminary and accelerated thermal stability and moisturizing efficacy. The formulations containing 0.5% of xanthan gum (FX) and 0.5% of xanthan gum and 1% of Opuntia ficus-indica MILL extract (FXE) were white, homogeneus and fluid in aspect. Both formulations were stable during preliminary and accelerated stability tests. FX and FXE presented a pH compatible to skin pH (4.5–6.0); droplet size varying from 92.2 to 233.6 nm; a polydispersion index (PDI) around 0.200 and a zeta potential from −26.71 to −47.01 mV. FXE was able to increase the water content of the stratum corneum for 5 h after application on the forearm. The O/W nanoemulsions containing 1% of Opuntia ficus-indica (L.) Mill extract presented suitable stability for at least for 60 days. Besides, this formulation was able to increase the water content of stratum corneum, showing its moisturizing efficacy.

Hyaluronan-phosphatidylethanolamine polymers form pericellular coats on keratinocytes and promote basal keratinocyte proliferation

Aged keratinocytes have diminished proliferative capacity and hyaluronan (HA) cell coats, which are losses that contribute to atrophic skin characterized by reduced barrier and repair functions. We formulated HA-phospholipid (phosphatidylethanolamine, HA-PE) polymers that form pericellular coats around cultured dermal fibroblasts independently of CD44 or RHAMM display. We investigated the ability of these HA-PE polymers to penetrate into aged mouse skin and restore epidermal function in vivo. Topically applied Alexa(647)-HA-PE penetrated into the epidermis and dermis, where it associated with both keratinocytes and fibroblasts. In contrast, Alexa(647)-HA was largely retained in the outer cornified layer of the epidermis and quantification of fluorescence confirmed that significantly more Alexa(647)-HA-PE penetrated into and was retained within the epidermis than Alexa(647)-HA. Multiple topical applications of HA-PE to shaved mouse skin significantly stimulated basal keratinocyte proliferation and epidermal thickness compared to HA or vehicle cream alone. HA-PE had no detectable effect on keratinocyte differentiation and did not promote local or systemic inflammation. These effects of HA-PE polymers are similar to those reported for endogenous epidermal HA in youthful skin and show that topical application of HA-PE polymers can restore some of the impaired functions of aged epidermis.

Hyaluronan and RHAMM in wound repair and the "cancerization" of stromal tissues

Tumors and wounds share many similarities including loss of tissue architecture, cell polarity and cell differentiation, aberrant extracellular matrix (ECM) remodeling (Ballard et al., 2006) increased inflammation, angiogenesis, and elevated cell migration and proliferation. Whereas these changes are transient in repairing wounds, tumors do not regain tissue architecture but rather their continued progression is fueled in part by loss of normal tissue structure. As a result tumors are often described as wounds that do not heal. The ECM component hyaluronan (HA) and its receptor RHAMM have both been implicated in wound repair and tumor progression. This review highlights the similarities and differences in their roles during these processes and proposes that RHAMM-regulated wound repair functions may contribute to “cancerization” of the tumor microenvironment.

Moisturizing effect of a cosmetic formulation containing pequi oil (Caryocar brasiliense) from the Brazilian cerrado biome

Caryocar brasiliense, popularly known in Brazil as “pequi”, is a species widely distributed in the Brazilian Cerrado. The seeds are surrounded by a woody endocarp coated with a yellow fleshy mesocarp rich in oil and vitamin A, whose oil has a useful role in the treatment of skin aging and protection of human skin against UV-induced damage and skin hydration. The aim of this study was to evaluate the effect of cosmetic formulations containing pequi oil (Caryocar brasiliense) on skin hydration, after a single application. Hydration effect assessment was performed by applying the formulations under study (Control – no formulation, vehicle, and vehicle + pequi oil) onto forearm skin of 30 human volunteers. Skin capacitance and Transepidermal Water Loss (TEWL) measurements were analyzed before, and at 1, 2 and 3 hours after, a single application. Evaluation results of a single application of the vehicle containing pequi oil showed an increase in stratum corneum water content, indicating a skin moisturizing effect. Results of the evaluation of immediate effects of TEWL demonstrated that the vehicle containing pequi oil significantly increased skin moisture during the 3 h evaluation period. The formulations containing pequi oil showed clinical efficacy, increasing stratum corneum water content and enhancing skin barrier function.

Microvascular dysfunction in the context of diabetic neuropathy

Microvascular dysfunction in diabetes plays a crucial role in the development of diabetic complications. The skin, as one of the most accessible organs, serves as a model for the investigation of microvascular dysfunction. Several non-invasive, mostly laser-Doppler-based methods have been developed lately to assess microvascular function in the skin. Microvascular functional changes occur even in the prediabetic state and become more complex with overt diabetes, being exacerbated by the presence of peripheral and/or autonomic diabetic neuropathy. The present article aims at shedding light on the implication of endothelial and neurovascular dysfunction in microvascular changes in diabetes, highlighting the contribution of different forms of diabetic neuropathy.

Determinants of breast appearance and aging in identical twins

BACKGROUND

Appearance, aging, and disorders of the breast are multifactorial. There are intrinsic, patient-specific characteristics, such as breast growth during puberty and propensity for breast cancer, which are primarily inherited. There are also environmental factors, which can be potentially controlled. Monozygotic twins provide an excellent research opportunity to examine the role of extrinsic factors in subjects with identical genetic predispositions.

OBJECTIVES

The authors investigate the role and significance of various environmental and acquired factors on breast aesthetics.

METHODS

Identical female twins were recruited during the Twins Days Festival in Twinsburg, Ohio, in 2009 and 2010. After consent was obtained, enrolled subjects completed a comprehensive survey on their medical and personal history. Standardized digital photographs were taken by medical photographers. Sixteen aesthetic breast features were subjectively rated by 6 plastic surgery residents blinded to the survey results. These ratings were then analyzed against survey data to determine the significance of different exogenous factors on breast appearance.

RESULTS

A total of 161 pairs of identical female twins (n = 322) with a mean (SD) age of 47.6 (14.5) years were recruited. Twins who moisturized their skin daily had significantly fewer rhytids (P = .002). Twins who received hormone replacement therapy after menopause had more attractive breast shape, size, projection, areolar shape, and areolar size (P < .03). However, twins who had a higher body mass index, greater number of pregnancies, and larger cup sizes had significantly less attractive breasts (P < .05). Twins who smoked cigarettes and consumed alcohol also had significantly less attractive breasts (P < .05). Twins who breastfed had less attractive areolar size and shape but better skin quality than their counterparts who never breastfed (P < .03). Finally, there was a significantly higher incidence of breast pain in twins who primarily slept on their sides compared with twins who primarily slept on their backs (P < .008).

CONCLUSIONS

This study implicates several environmental factors that significantly affect the aesthetic quality of breasts.