Applying a vernix caseosa based formulation accelerates skin barrier repair by modulating lipid biosynthesis

Applying Vernix Caseosa for Accidental Foetal Lacerations during Caesarean Delivery: A Case Series

The caesarean section is a frequently performed method of delivery. Although the caesarean section is a low-risk and safe surgery, there is an increase in maternal and infant morbidity and mortality due to caesarean delivery. One of the most common infant morbidities is foetal laceration. Caesarean delivery has a 1-2% risk of laceration to the foetus. Various methods have been proposed to deal with laceration wounds. Studies have been conducted on vernix caseosa, which can heal wounds on the skin. This case series report aims to demonstrate that vernix caseosa application is a wound healing method that is highly effective, costless, and of immediate availability.

Expert consensus on ceramides containing skincare in newborns and infants and potential mitigation of atopic dermatitis

INTRODUCTION

The vulnerable skin of neonates and infants is still developing anatomically and functionally and more susceptible to skin barrier disruption. The current consensus paper explores challenges in caring for neonates and infants' skin, skincare use and evaluates the role of ceramides (CERs) containing cleansers and moisturizers.

EVIDENCE AQUISITION

A panel of eight clinicians who treat neonates and infants developed a consensus paper on new-born and infant skin barrier integrity and CERs-containing skincare importance. The consensus process consisted of a modified Delphi technique. The selected information from the literature searches, coupled with the panel's opinion and experience, was used to adopt statements to provide clinical data for paediatric dermatologists, dermatologists, and paediatric healthcare providers who treat neonates and infants.

EVIDENCE SYNTHESIS

Increasingly, evidence supports skincare starting early in life, recognizing the benefits of ongoing daily use of non-alkaline cleansers and moisturizers to maintain skin barrier function. Skincare for neonates and infants should be safe, effective, and fragrance as well as sensitizing agent-free. Skincare with CERs may benefit the stratum corneum's lipid and water content.

CONCLUSIONS

When applied from birth onwards, gentle cleansers and moisturizers containing barrier lipids help maintain the protective skin barrier and soothe the skin with long-term moisturizing benefits.

The effect of vernix caseosa in preventing nipple problems among early postpartum women: A randomized-controlled single-blind clinical trial☆

BACKGROUND AND PURPOSE

Vernix caseosa, a natural substance similar to mother's milk with protective effects on the skin, might be effective in preventing nipple problems. The purpose of this study was to examine the potential efficacy of vernix caseosa compared to the conventional use of mother's milk in the prevention of postpartum nipple problems.

MATERIALS AND METHODS

This randomized, controlled, single-blind experimental study involved 64 primipara mothers who underwent cesarean section and were randomly and equally divided between the vernix caseosa group and the mother's milk group. All mothers received nipple care four times daily during the first postpartum week. Data were collected using personal information and nipple monitoring forms.

RESULTS

The incidence of nipple pain, rashes, and an abnormal appearance was similar in both groups on the first day postpartum (p = 0.132, p = 0.516, and p = 0.132, respectively), and none of the mothers had nipple cracks. On the seventh day, mothers in the vernix caseosa group had significantly less pain (p = 0.042), significantly reduced rash (p = 0.048), significantly higher satisfaction (p = 0.023), and no nipple cracks.

CONCLUSION

Nipple care with vernix caseosa is more effective than with mother's milk in preventing postpartum nipple pain, rashes, and cracks.

Impact of airborne particulate matter on skin: a systematic review from epidemiology to in vitro studies

BACKGROUND

Air pollution is killing close to 5 million people a year, and harming billions more. Air pollution levels remain extremely high in many parts of the world, and air pollution-associated premature deaths have been reported for urbanized areas, particularly linked to the presence of airborne nano-sized and ultrafine particles.

MAIN TEXT

To date, most of the research studies did focus on the adverse effects of air pollution on the human cardiovascular and respiratory systems. Although the skin is in direct contact with air pollutants, their damaging effects on the skin are still under investigation. Epidemiological data suggested a correlation between exposure to air pollutants and aggravation of symptoms of chronic immunological skin diseases. In this study, a systematic literature review was conducted to understand the current knowledge on the effects of airborne particulate matter on human skin. It aims at providing a deeper understanding of the interactions between air pollutants and skin to further assess their potential risks for human health.

CONCLUSION

Particulate matter was shown to induce a skin barrier dysfunction and provoke the formation of reactive oxygen species through direct and indirect mechanisms, leading to oxidative stress and induced activation of the inflammatory cascade in human skin. Moreover, a positive correlation was reported between extrinsic aging and atopic eczema relative risk with increasing particulate matter exposure.

Skin of atopic dermatitis patients shows disturbed β-glucocerebrosidase and acid sphingomyelinase activity that relates to changes in stratum corneum lipid composition

Patients with Atopic Dermatitis (AD) suffer from inflamed skin and skin barrier defects. Proper formation of the outermost part of the skin, the stratum corneum (SC), is crucial for the skin barrier function. In this study we analyzed the localization and activity of lipid enzymes β-glucocerebrosidase (GBA) and acid sphingomyelinase (ASM) in the skin of AD patients and controls. Localization of both the expression and activity of GBA and ASM in the epidermis of AD patients was altered, particularly at lesional skin sites. These changes aligned with the altered SC lipid composition. More specifically, abnormal localization of GBA and ASM related to an increase in specific ceramide subclasses [AS] and [NS]. Moreover we related the localization of the enzymes to the amounts of SC ceramide subclasses and free fatty acids (FFAs). We report a correlation between altered localization of active GBA and ASM and a disturbed SC lipid composition. Localization of antimicrobial peptide beta-defensin-3 (HBD-3) and AD biomarker Thymus and Activation Regulated Chemokine (TARC) also appeared to be diverging in AD skin compared to control. This research highlights the relation between correct localization of expressed and active lipid enzymes and a normal SC lipid composition for a proper skin barrier.

A Novel Effect of Lipids Extracted from Vernix Caseosa on Regulation of Filaggrin Expression in Human Epidermal Keratinocytes

BACKGROUND

Vernix caseosa (VC), which is known as a unique human substance, is a biofilm that covers the skin of most human newborns. VC has many biological functions including anti-infective, skin cleansing and skin barrier repair.

OBJECTIVE

In the study, we purpose to investigate the novel effect of lipids extracted from VC on the regulation of filaggrin (FLG) expression and anti-inflammation in normal human epidermal keratinocyte (NHEK) cells.

METHODS

The lipids were extracted by chloroform/methanol (Folch method) and the major properties of fatty acid methyl esters were determined with gas chromatography-mass spectrometer. The relative viability of NHEK cells was evaluated by Cell Counting Kit 8 assay. The related expression of skin barrier protein was accessed with real-time quantitative polymerase chain reaction, Western blot and Immunofluorescence in NHEK cells with or without poly (I:C). Meanwhile, the changes of thymic stromal lymphopoietin (TSLP) and tumor necrosis factor alpha (TNF-α) are analyzed by enzyme-linked immunosorbent assay.

RESULTS

VC lipids mostly contained saturated and branched chains fatty acids. The expression of mRNA and protein of FLG were significantly increased after the supplement with lipid in NHEK cells. Meanwhile, lipids reversed the inhibition of poly (I:C) on FLG. Moreover, lipids suppressed the over secretion of TSLP and TNF-α induced by poly (I:C).

CONCLUSION

These results indicate that lipids extracted from VC has positive effects on the expression of FLG and anti-inflammation, suggesting that lipids of VC may be used for a reference for novel therapeutic method in reducing and remedying skin disease like atopic disease.

The impact of recent advances in lipidomics and redox lipidomics on dermatological research

Dermatological research is a major beneficiary of the rapidly developing advances in lipid analytic technology and of bioinformatic tools which help to decipher and interpret the accumulating big lipid data. At its interface with the environment, the epidermis develops a blend of lipids that constitutes the epidermal lipid barrier, essential for the protection from water loss and entry of dangerous noxae. Apart from their structural role in the barrier, novel intra- and inter-cellular signaling functions of lipids and their oxidation products have been uncovered in most cutaneous cell types over the last decades, and the discovery rate has been boosted by the advent of high resolution and -throughput mass spectrometric techniques. Our understanding of epidermal development has benefited from studies on fetal surface lipids, which appear to signal for adaptation to desiccation post partum, and from studies on the dynamics of epidermal lipids during adjustment to the atmosphere in the first months of life. At birth, external insults begin to challenge the skin and its lipids, and recent years have yielded ample insights into the dynamics of lipid synthesis and -oxdiation after UV exposure, and upon contact with sensitizers and irritants. Psoriasis and atopic dermatitis are the most common chronic inflammatory skin diseases, affecting at least 3% and 7% of the global population, respectively. Consequently, novel (redox-) lipidomic techniques have been applied to study systemic and topical lipid abnormalities in patient cohorts. These studies have refined the knowledge on eicosanoid signaling in both diseases, and have identified novel biomarkers and potential disease mediators, such as lipid antigens recognized by psoriatic T cells, as well as ceramide species, which specifically correlate with atopic dermatitis severity. Both biomarkers have yielded novel mechanistic insights. Finally, the technological progress has enabled studies to be performed that have monitored the consequences of diet, lifestyle, therapy and cosmetic intervention on the skin lipidome, highlighting the translational potential of (redox-) lipidomics in dermatology.

Transcriptional control and transcriptomic analysis of lipid metabolism in skin barrier formation and atopic dermatitis (AD)

Introduction: Atopic dermatitis (AD) is a multifactorial ailment associated with barrier breach and intense systemic inflammation. Several studies over the years have shown the complex interplay of a large number of factors in governing the progression and outcome of AD. In addition to the diverse types of AD resulting due to variation in the intrinsic mechanisms giving rise to AD such as single nucleotide polymorphisms (SNPs), epigenetic alterations or transcriptional changes, extrinsic factors such as age, ancestry, ethnicity, immunological background of the subject, the interactions of the subject with environmental stimuli and existing microbiome in the periphery surrounding the subject account for further heterogeneity in the clinical manifestations of the disease. Areas covered: Here we have selectively discussed transcriptional regulation of genes associated with skin lipid metabolism in the context of AD. Transcriptional control and transcriptomic changes are just one face of this multifaceted disease known to affect humans and a detailed study concerning those will enable us to develop targeted therapies to deal with the disease. Expert opinion: Large-scale integration of different omics approaches (genomics, epigenomics, transcriptomics, lipidomics, proteomics, metabolomics, effect of exposome) will help identify the potential candidate gene(s) associated with the development of various endotypes of AD.

Noninvasive analysis and minimally invasive in vivo experimental challenges of the skin barrier

In this review, we aim to give a concise and selective overview of noninvasive biophysical analysis techniques for skin barrier analysis (transepidermal water loss, electrical methods, confocal Raman microspectroscopy, sebumeter, reflectance spectrophotometry, tristimulus colorimetry, diffuse reflectance spectroscopy and reflectance confocal microscopy), including advantages and limitations. Rather than giving an exhaustive description of the many techniques currently available, we show the usefulness of a representative selection of techniques in the functional and morphological evaluation of the skin barrier. Furthermore, we introduce human minimally invasive skin challenging models as a means to study the mechanisms regulating skin homoeostasis and disease and subsequently show how biophysical analysis techniques can be combined with these in vivo skin challenging models in the functional and morphological evaluation of the skin barrier in healthy human skin. We are convinced that the widespread application of biophysical analysis techniques in dermatological practice and in cosmetic sciences will prove invaluable in offering personalized and noninvasive skin treatment solutions. Furthermore, combining the human in vivo challenging models with these novel noninvasive techniques will provide valuable methodology and tools for detailed characterization of the skin barrier in health and disease.

Evaporative cooling provides a major metabolic energy sink

Objective

Elimination of food calories as heat could help redress the excess accumulation of metabolic energy exhibited as obesity. Prior studies have focused on the induction of thermogenesis in beige and brown adipose tissues as the application of this principle, particularly because the β-adrenergic environment associated with thermogenic activation has been shown to have positive health implications. The counterpoint to this strategy is the regulation of heat loss; we propose that mammals with inefficient heat conservation will require more thermogenesis to maintain body temperature.

Methods

Surface temperature thermography and rates of trans-epidermal water loss were integrated to profile the total heat transfer of genetically-engineered and genetically variable mice.

Results

These data were incorporated with energy expenditure data to generate a biophysical profile to test the significance of increased rates of evaporative cooling.

Conclusions

We show that mouse skins vary considerably in their heat retention properties, whether because of naturally occurring variation (SKH-1 mice), or genetic modification of the heat-retaining lipid lamellae (SCD1, DGAT1 or Agouti A^y obese mice). In particular, we turn attention to widely different rates of evaporative cooling as the result of trans-epidermal water loss; higher rates of heat loss by evaporative cooling leads to increased demand for thermogenesis. We speculate that this physiology could be harnessed to create an energy sink to assist with strategies aimed at treating metabolic diseases.

Dry skin management: practical approach in light of latest research on skin structure and function

Dry skin is a common condition that is attributed to a lack of water in the stratum corneum. With the availability of new technologies, light has been shed on the pathophysiology of dry skin at the molecular level. With the aim to discuss implications of this latest research for the optimal formulation of emollients designed to treat dry skin, five specialists met in November 2017. Research on three topics thereby provided particularly detailed new insights on how to manage dry skin: research on the lipid composition and organization of the stratum corneum, research on natural moisturizing factors, and research on the peripheral nervous system. There was consensus that latest research expands the rationale to include physiological lipids in an emollient used for dry skin, as they were found to be essential for an adequate composition and organization in the stratum corneum but are reduced in dry skin. Latest findings also confirmed the incorporation of carefully selected humectants into a topical emollient for dry skin, given the reduced activity of enzymes involved in the synthesis of moisturizing factors when skin is dry. Overall, the group of specialists concluded that the previous concept of the five components for an ideal emollient for dry skin is well in accordance with latest research.

Human skin equivalents cultured under hypoxia display enhanced epidermal morphogenesis and lipid barrier formation

Human skin equivalents (HSEs) are three-dimensional cell models mimicking characteristics of native human skin (NHS) in many aspects. However, a limitation of HSEs is the altered in vitro morphogenesis and barrier formation. Differences between in vitro and in vivo skin could have been induced by suboptimal cell culture conditions, of which the level of oxygen in vitro (20%) is much higher than in vivo (0.5-8%). Our aim is to study how external oxygen levels affect epidermal morphogenesis and barrier formation in HSEs. In the present study, fibroblast and keratinocyte monocultures, and HSEs were generated under 20% (normoxia) and 3% (hypoxia) oxygen level. In all cultures under hypoxia, expression of hypoxia-inducible factor target genes was increased. Characterization of HSEs generated under hypoxia using immunohistochemical analyses of morphogenesis biomarkers revealed a reduction in epidermal thickness, reduced proliferation, similar early differentiation, and an attenuated terminal differentiation program compared to normoxia, better mimicking NHS. The stratum corneum ceramide composition was studied with liquid chromatography coupled to mass spectrometry. Under hypoxia, HSEs exhibited a ceramide composition that more closely resembles that of NHS. Consequently, the lipid organization was improved. In conclusion, epidermal morphogenesis and barrier formation in HSEs reconstructed under hypoxia better mimics that of NHS.

Characterization of human skin equivalents developed at body's core and surface temperatures

Human skin equivalents (HSEs) are in vitro developed three‐dimensional models resembling native human skin (NHS) to a high extent. However, the epidermal lipid biosynthesis, barrier lipid composition, and organization are altered, leading to an elevated diffusion rate of therapeutic molecules. The altered lipid barrier formation in HSEs may be induced by standardized culture conditions, including a culture temperature of 37°C, which is dissimilar to skin surface temperature. Therefore, we aim to determine the influence of culture temperature during the generation of full thickness models (FTMs) on epidermal morphogenesis and lipid barrier formation. For this purpose, FTMs were developed at conventional core temperature (37°C) or lower temperatures (35°C and 33°C) and evaluated over a time period of 4 weeks. The stratum corneum (SC) lipid composition was analysed using advanced liquid chromatography coupled to mass spectrometry analysis. Our results show that SC layers accumulated at a similar rate irrespective of culture temperature. At reduced culture temperature, an increased epidermal thickness, a disorganization of the lower epidermal cell layers, a delayed early differentiation, and an enlargement of granular cells were detected. Interestingly, melanogenesis was reduced at lower temperature. The ceramide subclass profile, chain length distribution, and level of unsaturated ceramides were similar in FTMs generated at 37°C and 35°C but changed when generated at 33°C, reducing the resemblance to NHS. Herein, we report that culture temperature affects epidermal morphogenesis substantially and to a lesser extent the lipid barrier formation, highlighting the importance of optimized external parameters during reconstruction of skin.

New insight into phase behavior and permeability of skin lipid models based on sphingosine and phytosphingosine ceramides

The intercellular lipid matrix of the stratum corneum (SC), which consist mainly of ceramides (CERs), free fatty acids and cholesterol, is fundamental to the skin barrier function. These lipids assemble into two lamellar phases, known as the long and short periodicity phases (LPP and SPP respectively). The LPP is unique in the SC and is considered important for the skin barrier function. Alterations in CER composition, as well as impaired skin barrier function, are commonly observed in diseased skin, yet the understanding of this relationship remains insufficient. In this study, we have investigated the influence of non-hydroxy and α-hydroxy sphingosine-based CERs and their phytosphingosine counterparts on the permeability and lipid organization of model membranes, which were adjusted in composition to enhance formation of the LPP. The permeability was compared by diffusion studies using ethyl-p-aminobenzoate as a model drug, and the lipid organization was characterized by X-ray diffraction and infrared spectroscopy. Both the sphingosine- and phytosphingosine-based CER models formed the LPP, while the latter exhibited a longer LPP repeat distance. The ethyl-p-aminobenzoate flux across the sphingosine-based CER models was higher when compared to the phytosphingosine counterparts, contrary to the fact that the α-hydroxy phytosphingosine-based CER model had the lowest chain packing density. The unanticipated low permeability of the α-hydroxy phytosphingosine-based model is probably associated with a stronger headgroup hydrogen bonding network. Our findings indicate that the increased level of sphingosine-based CERs at the expense of phytosphingosine-based CERs, as observed in the diseased skin, may contribute to the barrier function impairment.

Preferential arrangement of lipids in the long-periodicity phase of a stratum corneum matrix model

The lipid matrix of the stratum corneum, the outermost skin layer, consists primarily of ceramides, cholesterol, and FFAs. These lipids form a trilayer long-periodicity phase (LPP) that is unique to this barrier. Knowledge about the LPP is essential in understanding the barrier function. Previous studies of LPP lipid models have identified the position of the major lipid classes and suggested that a large fraction of FFAs and the ceramide acyl chain are present in the central region. However, the precise arrangement, such as lipid subclass mixing (isolated or mixed) and ceramide conformation (extended or hairpin), remains unknown. Here, we deuterated FFAs and the ceramide acyl chain to study CD₂ and CH₂ interactions with Fourier-transform infrared spectroscopy. The ceramide and FFAs of various chain lengths were not in separate domains but had mixed together. The larger number of CD₂-CD₂ lipid chain interactions in the LPP than in a symmetrical bilayer structure implied that the ceramide had primarily adopted an extended conformation. Shorter FFAs were present in the central region of the LPP. This model explores the biophysical properties of the stratum corneum's LPP to improve the understanding of the barrier function of this layer.