Skin Barrier Function Research Articles

The biological effects of Rosa rugosa extract on keratinocyte differentiation and enhancement of skin barrier function

The biological effects of Rosa rugosa extract on keratinocyte differentiation and enhancement of skin barrier function

Bacteria, Fungi, and Scalp Psoriasis: Understanding the Role of the Microbiome in Disease Severity.

Background: Psoriasis is a chronic skin condition affected by genetic and environmental factors. Changes in the skin microbiome may affect the immune system and skin barrier functions, thereby contributing to the development and progression of psoriasis. The scalp, which is a common site for psoriasis, is often resistant to therapy. Although several studies have investigated the scalp microbiome, analyses focusing on both bacteria and fungi remain scarce. Methods: We examined the scalp microbiomes of 11 patients with psoriasis complicated with scalp lesions and categorized them according to their Psoriasis Area Severity Index (PASI) scores. The bacterial and fungal data were analyzed using QIIME2 pipeline version 2021.04 and the UNITE database version 8.3, respectively. Results: The Shannon indices for mild (2 patients), moderate (4 patients), and severe (5 patients) groups were 0.97, 1.38, and 1.88, respectively. A significant correlation was observed between increased mycobiome diversity and disease severity (p = 4.07 × 10-5, Spearman's correlation: 0.9269). Compared with the mild and moderate groups, the severe group exhibited a higher abundance of Malassezia globosa. Pseudomonas and Staphylococcus were, respectively, more prevalent in the moderate and severe groups than in the mild group. Conclusions: This study highlights the potential role of increased fungal diversity and specific microbial compositions in the severity of scalp psoriasis, suggesting a possible avenue for targeted therapeutic interventions.

Agrimonia coreana Extract Exerts Its Therapeutic Effect through CRAC Channel Inhibition for Atopic Dermatitis Treatment.

Atopic dermatitis (AD) is a common allergic inflammatory skin condition marked by severe itching, skin lichenification, and chronic inflammation. AD results from a complex immune response, primarily driven by T lymphocytes and environmental triggers, leading to a disrupted epidermal barrier function. Traditional treatments, such as topical corticosteroids, have limitations due to long-term side effects, highlighting the need for safer alternatives. Here, we aimed to show that Agrimonia coreana extract (ACext) can be used in treating AD-related dermatologic symptoms. ACext could inhibit CRAC (Calcium Release-Activated Calcium) channel activity, reducing Orai1/CRAC currents and decreasing intracellular calcium signaling. This inhibition was further confirmed by the reduced IL-2 levels and T cell proliferation upon ACext treatment. In a mouse model of AD, ACext significantly ameliorates symptoms, improves histological parameters, and enhances skin barrier function, demonstrating its potential for treating AD.

Skin sensing and wearable technology as tools to measure atopic dermatitis severity.

Wearable medical technology encompasses a range of electronic devices that act as biosensors. Atopic dermatitis (AD) is the commonest inflammatory skin disease and represents an important area of need in which to leverage the power of wearable biosensor technology, especially as the impact of COVID-19 increases the likelihood of virtual consultations becoming an integrated part of clinical practice. The aim of this review is to systematically define the published evidence for the utility of wearable biosensors in assessment and management of atopic dermatitis (AD). A systematic literature search was conducted for publications from 1995 onwards for 'sensor' OR 'sensing' OR 'biosensor' OR 'biomarker'. Results were combined ('AND') with a search for 'wearable' OR 'actigraphy' OR 'Internet of things' OR 'microneedle' OR 'patch' OR 'e-textile' OR 'smart textile' and atopic dermatitis (MESH terms). Fifty seven abstracts were identified from the database search of which 39 were selected for detailed review. Broadly, wearable sensing systems in atopic dermatitis were split into three categories: wearable biosensor modules (actigraphy and smartwatches), clothing and integrated fabrics placed onto the epidermis and intradermal or subcutaneous sensors. The best evidence for correlation with AD disease severity was with actigraphy measurements of itch. However, newer approaches including sensing skin barrier function, inflammation and small molecule analysis as well as employing artificial intelligence offer more potential for advanced disease monitoring. Skin diseases, specifically AD, stand to benefit greatly from wearable technology, because of the ease of direct contact to the skin, the high prevalence of the disease and the large unmet need for better disease control in this group. However, important emphasis must be placed on validating the correlation of data from such technology with patient-reported outcomes. Wearable biosensors offer a huge potential to deliver better diagnostics, monitoring and treatment outcomes for patients.

Beyond Skin Deep: Phospholipid-Based Nanovesicles as Game-Changers in Transdermal Drug Delivery.

Transdermal administration techniques have gained popularity due to their advantages over oral and parenteral methods. Noninvasive, self-administered delivery devices improve patient compliance and control drug release. Transdermal delivery devices struggle with the skin's barrier function. Molecules over 500 Dalton (Da) and ionized compounds don't permeate through the skin. Drug encapsulation in phospholipid-based vesicular systems is the most effective skin delivery technique. Vesicular carriers include bi-layered liposomes, ultra-deformable liposomes, ethanolic liposomes, transethosomes, and invasomes. These technologies enhance skin drug permeation by increasing formula solubilization, partitioning into the skin, and fluidizing the lipid barrier. Phospholipid-based delivery systems are safe and efficient, making them a promising pharmaceutical and cosmeceutical drug delivery technique. Still, making delivery systems requires knowledge about the physicochemical properties of the drug and carrier, manufacturing and process variables, skin delivery mechanisms, technological advances, constraints, and regulatory requirements. Consequently, this review covers recent research achievements addressing the mentioned concerns.

Terpene-based eutectic mixtures for cutaneous delivery: Eutectic point vs. molar ratio - which matters more?

Eutectic mixtures (EMs) of small molecules are increasingly used as a platform for dermal and transdermal drug delivery. However, there is still limited knowledge about how their composition impacts their permeation-enhancing effect, with most studies focusing only on formulations corresponding to the eutectic points (EPs) of binary mixtures. To address this, we investigated the role of the EMs' molar composition on their potential as a delivery platform for the model drug clotrimazole (CLOT). We examined several molar ratios of four terpene-based EMs composed of menthol:β-citronellol, thymol:β-citronellol, menthol:camphor and menthol:thymol for their CLOT-solubilizing potential and viscosity. We also studied CLOT skin retention and permeation after applying the CLOT-containing EMs to porcine skin and observed changes in the skin barrier function. For EMs without thymol, the solubility of CLOT in the EMs was independent of the molar ratio between the terpenes. In contrast, the solubility in thymol-based EMs depended on the molar ratio between the terpenes, with the lowest solubilities found for the EMs at their EPs. The viscosity of pure EMs was dictated by their molar composition, and when saturated with CLOT, it was largely governed by the amount of the dissolved drug in the mixtures, also at their EPs. A small amount of CLOT permeated through the porcine skin, with larger quantities of the drug found in the epidermis and, to lesser extent, in the dermis. The amount of CLOT found in the skin did not correlate with the degree of skin impairment and disruption of the lipid packing in the stratum corneum. Importantly, EMs at their EPs did not show better CLOT retention and permeation than the other EMs. Instead, skin retention of CLOT was dependent on the content of terpenes in the EMs, viscosity of the mixtures, and to some extent the drug solubility, rather than a particular ratio between them.

Rosacea in East Asian populations: Clinical manifestations and pathophysiological perspectives for accurate diagnosis.

Rosacea is a chronic inflammatory disorder primarily affecting the facial skin, prominently involving the cheeks, nose, chin, forehead, and periorbital area. Cutaneous manifestations encompass persistent facial erythema, phymas, papules, pustules, telangiectasia, and flushing. The pathogenesis of rosacea is associated with various exacerbating or triggering factors, including microbial infestation, temperature fluctuations, sunlight exposure, physical exertion, emotional stress, consumption of hot beverages and spicy foods, and exposure to airborne pollen. These environmental factors interact with genetic predispositions in the development of rosacea. The roles of the lipophilic microbiome, ultraviolet radiation, nociceptive responses, and vascular alterations have been proposed as significant factors in the pathogenesis. These insights contribute to understanding the anatomical specificity of facial involvement and the progressive nature of rosacea. East Asian skin, predominantly classified as Fitzpatrick skin phototypes III to IV, is characterized by relatively diminished skin barrier function and increased sensitivity to irritants. Airborne pollen exposure may particularly act as a trigger in East Asian individuals, possibly mediated through toll-like receptors. The lack of specificity in objective clinical and histopathological findings leads to diagnostic challenges for individuals with colored skin, including East Asians, particularly when erythema is the sole objective manifestation. An alternative diagnostic scheme may thus be necessary. A diagnostic approach emphasizing vascular manifestations and nociceptive symptoms potentially holds promise for individuals with darker skin tones. More research focusing on potential variations in skin physiology across different racial groups is essential to establish more effective diagnostic schemes applicable to both dark and light skin colors.

Unravelling the Complexities and Recent Advances in the Management of Atopic Dermatitis

Abstract: Atopic dermatitis (AD) is a non-fatal, non-communicable, chronic skin inflammatory condition marked by itching, lesions, and skin barrier dysfunction. As per the International Eczema Council, as of 2022, more than 200 million people were suffering from AD, with the disease burden reported highest in children. Environmental factors, genetic predisposition, and lifestyle have been found to be essential factors in triggering the adverse skin response. In this review, we provide a detailed overview of the pathophysiology of AD, how the skin barrier gets altered from normal condition to AD, and the role of genetic defects in Filaggrin protein, affecting the skin barrier function by altering the skin pH and hydration. Also, we highlight the role of toll-like receptors (TLRs) and the altered skin and gut microbiota in inducing chronic inflammatory responses and playing a significant role in the pathogenesis of the disease. Further, we discuss the role of several chemokines and cytokines, which could serve as important prognosis markers for early detection, monitoring the disease progression, and assessing the response to the treatment. We also report the current treatment regime of multimodal therapeutics ranging from topical emollients to topical, oral, and injectable immune modulatory agents. Besides, we discuss the importance of the gut-skin microbiome axis and the increasingly important role of prebiotics in AD treatment.

Skin barrier, phenotypic and genotypic characterisation of autosomal recessive ichthyosis in TGM1-deficient Jack Russell Terriers and response to topical ceramide.

Autosomal recessive ichthyosis leads to structural or biochemical changes that impair skin barrier function. To assess (1) the phenotype and genotype in a litter of Jack Russell Terriers with autosomal recessive congenital ichthyosis (ARCI), and (2) the defective skin barrier and determine if a topical ceramide can modulate the barrier. A healthy dam and litter of Jack Russell Terrier puppies (healthy male, affected male and female), one affected adult Jack Russell Terrier and one unrelated healthy Jack Russell Terrier. A severe cornification defect was identified via examination of affected puppies. As the phenotype worsened, the affected puppies received a topical application of ω-0-acylceramide for 10 days. Before humane euthanasia, the skin barrier was evaluated via transepidermal water loss (TEWL), corneometry and pH in affected dogs. Genomic testing was performed, and skin samples were analysed by light and electron microscopy. Affected puppies were homozygous for the 1980 bp LINE-1 insertion in the TGM1 (transglutaminase 1) gene; the unaffected littermate and the dam were heterozygous carriers. ARCI puppies were underweight and had a severe hyperkeratotic phenotype that impaired mobility. TEWL was markedly higher in affected dogs. The cutaneous pH of affected puppies was higher than the normal littermate. Treatment of the skin with ω-0-acylceramide normalised the pH to match the littermate and decreased TEWL. Electron microscopy revealed marked attenuation of the cornified envelope. Dogs with TGM1-deficient ARCI have an impaired skin barrier. Topical therapy can partially repair the barrier defect.

Improvement effects of tapinarof on the skin barrier function in Japanese patients with atopic dermatitis

Background: Tapinarof is a nonsteroidal, topical, aryl hydrocarbon receptor agonist. Tapinarof has been shown to be efficacious and have acceptable safety profile in the treatment of atopic dermatitis (AD).Objective: We sought to evaluate the improvement effect of tapinarof on skin barrier function in patients with AD.Methods: This was an open-label, uncontrolled, single-center study. Japanese patients aged ≥20 years with AD (N = 30) were included in this study. Patients applied tapinarof cream 1% once daily to the target areas on the volar forearm for 8 weeks. The primary endpoints were changes from baseline in stratum corneum hydration (SCH) and transepidermal water loss (TEWL) at the target affected area at week 8.Results: The mean SCH value at the target affected area was 13.656 AU at baseline, 16.904 AU at week 4, and 16.423 AU at week 8. The SCH at the target affected area significantly increased from baseline to week 8, with a mean change of 2.826 AU (p = 0.0433). The mean TEWL value at the target affected area was 17.35 g/m2/hr at baseline, 10.01 g/m2/hr at week 4, and 9.52 g/m2/hr at week 8. The TEWL at the target affected area significantly decreased from baseline to week 8, with a mean change of −8.03 g/m2/hr (p < 0.0001). Clinical signs of AD at the target affected area were improved over time. No serious, severe, or treatment-related AEs were reported.Conclusion: Treatment with tapinarof led to an increase in SCH and a decrease in TEWL in patients with AD, indicating the potential improvement effect of tapinarof on skin barrier function.

Holistic investigation of the anti-wrinkle and repair efficacy of a facial cream enriched with C-xyloside.

To investigate the repairing and anti-wrinkle efficacy of the facial cream enriched with C-xyloside, aiming at comprehensively evaluating its skin anti- aging effect and clarify its potential mechanism of action. The repairing efficacy was studied on 3D epidermis skin model and the antiaging efficacy was studied on ex-vivo human skin. Two clinical studies were conducted with Chinese females. In the first study, 49 subjects aged between 30 and 50 with wrinkle concerns were recruited and instructed to apply the investigational cream containing C-xyloside for 8 weeks. Wrinkles attributes were assessed by dermatologist. Instrumental measurements on skin hydration, trans-epidermal water loss (TEWL), and skin elasticity were also conducted. In the second study, 30 subjects aged between 25 and 60 with self-declared sensitive skin and facial redness were recruited and instructed to apply the cream for 4 weeks. Biomarker analysis of the stratum corneum was conducted through facial tape strips. The cream improved the histomorphology of the 3D epidermis skin model after SLS stimulation, and significantly increase the expression of LOR and FLG. On human skin, the cream improved the histopathology induced by UV, and significantly increased the protein content of COL I and COL III, collagen density and the number of Ki-67 positive cell of skin compared with model group (n = 3, p < 0.01). The results from the first clinical study demonstrate a significant increased the skin hydration and elasticity by 21.90%, 13.08% (R2) and 12.30% (R5), respectively (n = 49, p < 0.05), and the TEWL values decreased by 33.94% (n = 49, p < 0.05), after 8 weeks application of the cream. In addition, the scores for nasolabial folds, glabellar wrinkle, underneath eye wrinkles, crow's feet wrinkle and forehead wrinkle in the volunteers exhibited a significant reduction of 34.02%, 43.34%, 50.03%, 33.64% and 55.81% respectively (n = 49, p < 0.05). The (rCE)/(fCE) ratio of volunteers based on tape stripping significant increased after using the sample cream (n = 30, p < 0.05). The cream containing C-xyloside showed improvement of skin wrinkles and enhancement of skin barrier function. These efficacies may be attributed to the fact that the sample cream can increase the expression of skin barrier related proteins LOR and FLG, promote the maturation of cornified envelope, enhance collagen I and III protein expression and stimulate skin cell proliferation, to provide sufficient evidence supporting its antiaging efficacy of skin.

Zinc-Alpha-2-Glycoprotein Peptide Downregulates Type I and III Collagen Expression via Suppression of TGF-β and p-Smad 2/3 Pathway in Keloid Fibroblasts and Rat Incisional Model.

Keloids and hypertrophic scars result from abnormal collagen accumulation and the inhibition of its degradation. Although the pathogenesis remains unclear, excessive accumulation of the extracellular matrix (ECM) is believed to be associated with the TGF-β/SMAD pathway. Zinc-alpha-2-glycoprotein (ZAG) inhibits TGF-β-mediated epithelial-to-mesenchymal transdifferentiation and impacts skin barrier functions. In this study, we investigated the potential of a small ZAG-derived peptide against hypertrophic scars and keloids. The study examined cell proliferation and mRNA expression of collagen types I and III in human dermal fibroblast (HDF) cell lines and keloid-derived fibroblasts (KF) following ZAG peptide treatment. A rat incisional wound model was used to evaluate the effect of ZAG peptide in scar tissue. Significantly lower mRNA levels of collagen types I and III were observed in ZAG-treated fibroblasts, whereas matrix metalloproteinase (MMP)-1 and MMP-3 mRNA levels were significantly increased in HDFs and KFs. Furthermore, ZAG peptide significantly reduced protein expression of collagen type I and III, TGF-β1, and p-Smad2/3 complex in KFs. Rat incisional scar models treated with ZAG peptide presented narrower scar areas and reduced immature collagen deposition, along with decreased expression of collagen type I, α-SMA, and p-Smad2/3. ZAG peptide effectively suppresses the TGF-β and p-Smad2/3 pathway and inhibits excessive cell proliferation during scar formation, suggesting its potential therapeutic implications against keloids and hypertrophic scars.

Protein degradation in the stratum corneum.

The stratum corneum (SC), the outermost epidermal layer, plays a pivotal role in skin barrier function. This review delves into the intricate process of protein degradation within the stratum corneum, elucidating the roles of specific enzymes, regulatory mechanisms and the consequent impact on various skin conditions. Protein degradation is a finely tuned process, orchestrated by a suite of proteolytic enzymes like kallikreins. These enzymes are responsible for the breakdown of corneodesmosomes and the orderly desquamation of corneocytes, a process essential for skin homeostasis. Another critical enzymatic process is the breakdown of proteins like filaggrin and the generation of amino acids and their derivatives, required in the physiological water-handling properties of the SC. Regulation of these proteolytic activities is complex, involving a balance between endogenous inhibitors and other factors like pH, hydration and environmental stressors. Dysregulation of protease activity is linked to a spectrum of skin conditions, ranging from xerosis to inflammatory diseases like atopic dermatitis and psoriasis. Aberrant protein degradation can lead to compromised skin barrier function, increased tissue water loss and heightened susceptibility to infections and allergens. Understanding the factors affecting protein degradation can inform the development of targeted skincare products. Advances in biochemistry and dermatology have paved the way for the search for active ingredients designed to modulate protease activity. Such innovations may offer promising therapeutic avenues for enhancing skin barrier function and treating skin disorders. This review underscores the significance of enzymatic protein degradation in the SC and its regulatory mechanisms. It provides insights into the pathophysiology of skin diseases and outlines the potential for novel skincare interventions. By bridging the gap between fundamental research and practical applications, this article aims to inspire further investigation for better understanding of skin physiology and innovation in the realm of skincare product development.

Impact of multilamellar formulations on stratum corneumlipid organization and epidermal lipid barrier enhancement (Part II).

The integrity of the stratum corneum (SC) is crucial for the skin's barrier function, protecting against environmental stressors and minimizing transepidermal water loss. Advances in skincare formulations have introduced multilamellar systems designed to emulate the SC's lipid composition and organization. This study hypothesizes that the application of a multilamellar cream will significantly impact the SC's lipid content and lamellar structure, thereby enhancing the epidermal barrier. A saturated phosphatidylcholine-based multilamellar cream was applied to a cohort of adult subjects with very dry skin. Electron microscopy was utilized to analyse the micro-morphology of the cream and its integration into the lipid-depleted SC. Lipid analysis was conducted to quantify changes in the intercellular lipid matrix. Transmission-electron microscopy (TEM) imaging demonstrated that the multilamellar cream possesses a structured arrangement comparable to the natural SC architecture. Short-term application revealed a time-dependent restoration of lipid bilayers, while a 14-day regimen showed a marked increase in lipid lamellae density and length within the SC. Lipid analysis indicated a significant increase in total lipid content, with notable enhancements in ceramide and free fatty acid levels, without altering cholesterol levels. Lipid ratio analysis further confirmed the rebalancing of the SC's lipid composition. The multilamellar cream selectively increased specific lipids critical for barrier function, suggesting an action mechanism that aligns with the skin's natural regulatory processes. This selective augmentation indicates the potential of the formulation to not only restore but also enhance the epidermal barrier, with the maintenance of physiological lipid ratios suggesting compatibility with intrinsic repair mechanisms. The study confirms that a multilamellar cream can significantly improve the SC's lipid composition and structural integrity, indicating enhanced barrier function. They are pivotal for skincare professionals, dermatologists, and product developers, enriching the understanding of multilamellar creams' benefits and applications in improving epidermal barrier function.

Clinical efficacy of a multilamellar cream on skin physiology and microbiome in an epidermal stress model: A controlled double-blinded study.

Stratum corneum (SC) is essential for skin barrier function, mitigating water loss and shielding against potentially harmful substances and allergens. The SC's lipid matrix, arranged in a lamellar structure, is integral to its protective role. Our study explores the restoration effects of a multilamellar cream with an acidic pH compared to a basic placebo cream on skin physiology and its interaction with the skin microbiome after stress induction via tape stripping (TS). In this double-blind study, 14 healthy participants aged 21-58 years were assessed pre- and post-tape stripping, followed by a 14 days application of a multilamellar test cream and a placebo cream with evaluations on days 7, 14 and 17 for sustained effects. Skin physiology was analysed in terms of epidermal barrier function, SC hydration and surface pH. The microbiome was analysed by 16S rRNA amplicon sequencing the 16S rRNA gene using Illumina MiSeq, with subsequent species identification. Our study showed significant improvements in skin barrier repair and SC hydration with verum, particularly after 14 days of application, while both creams initially enhanced stratum corneum hydration. No significant changes in surface-pH were detected. The skin microbiome analysis revealed that TS slightly decreased alpha diversity, a trend that verum significantly reversed, enhancing diversity beyond baseline levels after 14 days. Overall, while both creams contributed to a broader microbial phyla diversity over time, no significant changes in the abundance of specific genera or species were noted between treatments. Our study delineates the efficacy of a pH-optimized multilamellar cream in enhancing epidermal barrier recovery and SC hydration post-sequential TS, in contrast to an unstructured basic placebo. Verum cream significantly improved skin barrier function and SC hydration at day 14, with sustained effects evident beyond the treatment period. Furthermore, the multilamellar formulation facilitated the restitution of cutaneous microbiome diversity, a key indicator of healthy skin ecology, underscoring the symbiotic relationship between barrier integrity and microbial composition. These findings underscore the importance of multilamellar emollient structures in dermatological therapeutics, with potential implications for the design of advanced skincare interventions that holistically support cutaneous resilience and homeostasis.

The role of ceramides in skin barrier function and the importance of their correct formulation for skincare applications.

Ceramides are a family of lipids constituted by a sphingoid base and a fatty acid. In the skin, they are mainly present in the stratum corneum where, with cholesterol and free fatty acids, they constitute the inter-corneocyte lipids. With the other lipid groups, they play a key role in the formation of dense lamellar structures between adjacent corneocytes, collectively ensuring the vital efficient barrier to water evaporation and protection from foreign agents´ penetration. Changes in ceramide level and relative composition, with potential impairment of lipid arrangement, have been evidenced in different skin conditions and skin diseases. Therefore, use of suitably formulated ceramides has been proposed for topical treatment to help re-structure damaged lipid arrangement and repair impaired skin barrier function. Nonetheless, the formulation of ceramides in products necessitates specific processes such as heating to high temperature before their introduction in the final formula. In this review on the structure, the role and the potential of ceramides for skincare, we point out the necessity of rigorous process when formulating ceramides into the final product. We demonstrate the counterproductive effects of undissolved ceramides on skin barrier repair capacity of the formulas, when assessed in different invitro models of disrupted skin barrier.

Investigation of keratolytic impact of synthetic bolalipids on skin penetration of a model hydrophilic permeant

Synthetic single-chain bolalipids (SSCBs) are novel excipients in drug delivery, with potential as stabilizers or solubilizers. However, their impact on skin barrier function has not been comprehensively studied. Therefore, two SSCBs (PC-C24-PC and PC-C32-PC) were studied in aqueous systems for their impact on penetration of a model permeant into porcine skin. Concentrations of 0.05 – 5 % w/w were tested; PC-C24-PC formulations were low-viscosity liquids while PC-C32-PC formed viscous dispersions to gels at room temperature. Formulations were compared for their ability to enhance sodium fluorescein penetration (SF, 0.1 % w/w) into skin via tape stripping. Using NIR-densitometry, the effect of SSCB formulations on corneocyte cohesion was evaluated. Data were compared with phospholipid mixture Lipoid S-75, sodium dodecyl sulfate (SDS), and polyethylene glycol 12-hydroxystearate (PEG-HS), and distilled water as negative control. Contrary to the hypothesis, both SSCBs failed to increase SF penetration into the stratum corneum, but rather showed a significant decrease in penetration depth compared to water. Both SSCBs exhibited a keratolytic effect at 5 % w/w, leading to substantial removal of proteins from the skin surface. Consequently, SSCBs may not enhance penetration of hydrophilic drugs into skin, but could be used as keratolytic agents.

Challenges in Adult Acne and the Role of Skin Care in Managing the Condition.

Acne vulgaris is a complex, multifactorial, inflammatory skin condition. Although frequently presented at dermatology clinics, the literature on adult acne is scarce, particularly concerning skin barrier function and management. We aimed to provide insights into the role of skin barrier integrity in adult acne patients and the role of cleansers and moisturizers as adjunctive to treating and maintaining adult acne.&nbsp;&nbsp; Methods: A panel of eight dermatologists who treat adult patients with acne developed a consensus paper on the role of skin barrier function and skin care in adult acne management. The modified Delphi method comprised a face-to-face meeting and online follow-up to discuss the results of a scoping literature review. Drawing from their experience and opinions, they agreed on seven consensus statements.&nbsp;&nbsp; Results: Epidermal barrier dysfunction plays a vital role in acne pathogenesis and asymmetrically impacts adult female acne. Erythema, pruritus, peeling, and xerosis are common adverse effects of first-line acne treatment options and, if not appropriately counseled and managed, can exacerbate, leading to regimen nonadherence and poor patient experience and outcomes. Improving patient knowledge of comprehensive acne treatments, including quality adjunctive cleansers and moisturizers, may maximize regimen efficacy and provide patients with personalized and successful acne treatment and maintenance tools. J Drugs Dermatol. 2024;23(8):674-679.&nbsp; &nbsp;&nbsp; doi:10.36849/JDD.8471.

Biomarkers in Pemphigus Vulgaris: A Systematic Review.

Pemphigus vulgaris (PV) is a rare intraepidermal blistering disease that is potentially life-threatening due to risk of infection and failure of skin barrier function. The identification of biomarkers has the potential to provide diagnostic utility and identify new therapeutic targets. The objective of this systematic review is to identify all potentially relevant PV biomarkers, categorize them, and identify trends to determine the involvement of T-cell-mediated, B-cell-1mediated, and innate immune-mediated pathways in PV pathogenesis. Medline and Embase databases were searched according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, resulting in the inclusion of 66 studies that reported on a total of 2463 patients and 146 unique biomarkers. Biomarkers were categorized into T-cell-mediated, B-cell-mediated, and innate immune system pathways. The most notable biomarkers trends include elevations in IL-4, IL-6, IL-17A, anti-Dsg1/3 autoantibodies, and a reduction in Treg cells and FOXP3. The results of this review support current theories of PV pathogenesis, with increased Th2 activity, increased Th17 activity, decreased Treg activity, and production of anti-Dsg1/3 autoantibodies being observed. Targeting of IL-4 and IL-6 may provide therapeutic benefit. However, more research is required to validate biomarkers for clinical utility and assess viability as therapeutic targets.

Correlations between Skin Condition Parameters and Ceramide Profiles in the Stratum Corneum of Healthy Individuals.

Ceramides are essential lipids for skin barrier function, and various classes and species exist in the human stratum corneum (SC). To date, the relationship between skin conditions and ceramide composition in healthy individuals has remained largely unclear. In the present study, we measured six skin condition parameters (capacitance, transepidermal water loss, scaliness, roughness, multilayer exfoliation, and corneocyte cell size) for the SC of the cheeks and upper arms of 26 healthy individuals and performed correlation analyses with their SC ceramide profiles, which we measured via liquid chromatography-tandem mass spectrometry. In the cheeks, high levels and/or ratios of two free ceramide classes containing an extra hydroxyl group in the long-chain moiety and a protein-bound ceramide class containing 6-hydroxysphingosine correlated with healthy skin conditions. In contrast, the ratios of two other free ceramide classes, both containing sphingosine, and a protein-bound ceramide class containing 4,14-sphingadiene correlated with unhealthy skin conditions, as did shortening of the carbon chain of the fatty acid portion of two ceramide classes containing non-hydroxy fatty acids. Thus, our findings help to elucidate the relationship between skin conditions and ceramide composition.