Menopause induces changes to the stratum corneum ceramide profile, which are prevented by hormone replacement therapy

Bioactive lipids in the skin barrier mediate its functionality in health and disease

Our skin protects us from external threats including ultraviolet radiation, pathogens and chemicals, and prevents excessive trans-epidermal water loss. These varied activities are reliant on a vast array of lipids, many of which are unique to skin, and that support physical, microbiological and immunological barriers. The cutaneous physical barrier is dependent on a specific lipid matrix that surrounds terminally-differentiated keratinocytes in the stratum corneum. Sebum- and keratinocyte-derived lipids cover the skin's surface and support and regulate the skin microbiota. Meanwhile, lipids signal between resident and infiltrating cutaneous immune cells, driving inflammation and its resolution in response to pathogens and other threats. Lipids of particular importance include ceramides, which are crucial for stratum corneum lipid matrix formation and therefore physical barrier functionality, fatty acids, which contribute to the acidic pH of the skin surface and regulate the microbiota, as well as the stratum corneum lipid matrix, and bioactive metabolites of these fatty acids, involved in cell signalling, inflammation, and numerous other cutaneous processes. These diverse and complex lipids maintain homeostasis in healthy skin, and are implicated in many cutaneous diseases, as well as unrelated systemic conditions with skin manifestations, and processes such as ageing. Lipids also contribute to the gut-skin axis, signalling between the two barrier sites. Therefore, skin lipids provide a valuable resource for exploration of healthy cutaneous processes, local and systemic disease development and progression, and accessible biomarker discovery for systemic disease, as well as an opportunity to fully understand the relationship between the host and the skin microbiota. Investigation of skin lipids could provide diagnostic and prognostic biomarkers, and help identify new targets for interventions. Development and improvement of existing in vitro and in silico approaches to explore the cutaneous lipidome, as well as advances in skin lipidomics technologies, will facilitate ongoing progress in skin lipid research.

Skin Surface Sebum Analysis by ESI-MS

The skin surface is an important sample source that the metabolomics community has only just begun to explore. Alterations in sebum, the lipid-rich mixture coating the skin surface, correlate with age, sex, ethnicity, diet, exercise, and disease state, making the skin surface an ideal sample source for future noninvasive biomarker exploration, disease diagnosis, and forensic investigation. The potential of sebum sampling has been realized primarily via electrospray ionization mass spectrometry (ESI-MS), an ideal approach to assess the skin surface lipidome. However, a better understanding of sebum collection and subsequent ESI-MS analysis is required before skin surface sampling can be implemented in routine analyses. Challenges include ambiguity in definitive lipid identification, inherent biological variability in sebum production, and methodological, technical variability in analyses. To overcome these obstacles, avoid common pitfalls, and achieve reproducible, robust outcomes, every portion of the workflow-from sample collection to data analysis-should be carefully considered with the specific application in mind. This review details current practices in sebum sampling, sample preparation, ESI-MS data acquisition, and data analysis, and it provides important considerations in acquiring meaningful lipidomic datasets from the skin surface. Forensic researchers investigating sebum as a means for suspect elimination in lieu of adequate fingerprint ridge detail or database matches, as well as clinical researchers interested in noninvasive biomarker exploration, disease diagnosis, and treatment monitoring, can use this review as a guide for developing methods of best-practice.

Serotonin Signaling through Lipid Membranes

Serotonin (5-HT) is a vital modulatory neurotransmitter responsible for regulating most behaviors in the brain. An inefficient 5-HT synaptic function is often linked to various mental disorders. Primarily, membrane proteins controlling the expression and activity of 5-HT synthesis, storage, release, receptor activation, and inactivation are critical to 5-HT signaling in synaptic and extra-synaptic sites. Moreover, these signals represent information transmission across membranes. Although the lipid membrane environment is often viewed as fairly stable, emerging research suggests significant functional lipid-protein interactions with many synaptic 5-HT proteins. These protein-lipid interactions extend to almost all the primary lipid classes that form the plasma membrane. Collectively, these lipid classes and lipid-protein interactions affect 5-HT synaptic efficacy at the synapse. The highly dynamic lipid composition of synaptic membranes suggests that these lipids and their interactions with proteins may contribute to the plasticity of the 5-HT synapse. Therefore, this broader protein-lipid model of the 5-HT synapse necessitates a reconsideration of 5-HT's role in various associated mental disorders.

Transcriptomics- and Genomics-Guided Drug Repurposing for the Treatment of Vesicular Hand Eczema

Vesicular hand eczema (VHE), a clinical subtype of hand eczema (HE), showed limited responsiveness to alitretinoin, the only approved systemic treatment for severe chronic HE. This emphasizes the need for alternative treatment approaches. Therefore, our study aimed to identify drug repurposing opportunities for VHE using transcriptomics and genomics data. We constructed a gene network by combining 52 differentially expressed genes (DEGs) from a VHE transcriptomics study with 3 quantitative trait locus (QTL) genes associated with HE. Through network analysis, clustering, and functional enrichment analyses, we investigated the underlying biological mechanisms of this network. Next, we leveraged drug-gene interactions and retrieved pharmaco-transcriptomics data from the DrugBank database to identify drug repurposing opportunities for (V)HE. We developed a drug ranking system, primarily based on efficacy, safety, and practical and pricing factors, to select the most promising drug repurposing candidates. Our results revealed that the (V)HE network comprised 78 genes that yielded several biological pathways underlying the disease. The drug-gene interaction search together with pharmaco-transcriptomics lookups revealed 123 unique drug repurposing opportunities. Based on our drug ranking system, our study identified the most promising drug repurposing opportunities (e.g., vitamin D analogues, retinoids, and immunomodulating drugs) that might be effective in treating (V)HE.

Dietary supplementation with a wheat polar lipid complex improves skin conditions in women with dry skin and mild-to-moderate skin aging

BACKGROUND

Aging, menopause, and seasonal changes alter the lipid composition of the outermost skin layer, the stratum corneum, resulting in dry and itchy skin.

AIMS

This clinical trial aimed at evaluating the effects of a wheat polar lipid complex (WPLC) on skin characteristics in women showing dry and wrinkled skin, investigating its effects in a subgroup of postmenopausal women, and assessing if benefits were maintained after supplementation.

METHODS

Seventy-two women with dry and wrinkled skin were recruited in this double-blind, randomized, parallel-group study, and allocated to three groups of 24 subjects, each including at least 10 postmenopausal women. For 56 days, subjects consumed the WPLC supplement (oil or powder), or the placebo. Skin hydration, transepidermal water loss (TEWL), elasticity, and profilometry were evaluated at baseline, after 14, 28, and 56 days of supplementation, and 56 days after the end of supplementation. Additionally, a lipidomic analysis was performed to examine changes in superficial skin layers over 56 days.

RESULTS

Dietary supplementation with WPLC rapidly improved all parameters. It increased skin hydration, smoothness, and elasticity while decreasing TEWL, roughness, and wrinkle depth after only 14 days of supplementation. These effects were also observed in the subpopulation of postmenopausal women and led to an improved self-perception of skin. For all the parameters, outcomes were not maintained after the supplementation was stopped. The lipidomic analysis revealed 10 compounds evolving over the 56 days of WPLC supplementation.

CONCLUSION

WPLC supplementation improved skin hydration, smoothness, elasticity, and wrinkledness within 14 days and, as expected, did not last after supplementation was stopped.

Identification of types of wound bed tissue as a percentage and total wound area by planimetry in neuropathic and venous ulcers

BACKGROUND

Neuropathic and venous leg ulcers are chronic wounds associated with devitalized tissue and recurrent infection. Management should be guided by accurate tissue assessment, including the use of planimetry, which provides tissue types as a percentage of the total wound bed surface area.

OBJECTIVE

This innovative study aimed to assess and identify the wound bed tissues, as a percentage, of neuropathic and venous ulcers using digital planimetry, providing support to nurses optimize the management of necrotic tissues and, consequently, to avoid wound infection.

METHODS

This cross-sectional study enrolled 24 patients with chronic wounds who were assessed from January to March 2021 at the Wound Outpatients Clinic. The wound photographs were analyzed using Image J 1.53e and a smartphone with WoundDoc Plus® 2.8.2 via digital planimetry. Statistical analyses were performed using the binomial test, t-test, and Mann-Whitney.

RESULTS

Median wound areas (p=0.3263) did not differ between the group with 2 or 3 risk factors for delayed healing (Md: 31.7) and the group with up to 1 risk factor (Md: 5.3). A low exudate level was associated with the up-to-1-risk-factor-for-delayed-healing group (p=0.0405), while a medium level was associated with the two-or-three-risk-factor group (p=0.0247). A heat map displayed the tissue percentages in the wound bed. In the group with 2 or 3 risk factors for delayed healing, 91.7% (11/12) had less than 70% granulation tissue, which was the primary factor for this group (p<0.0001). Additionally, 66.7% (8/12) of patients with 2 or 3 risk factors for delayed healing exhibited discolored and/or dark red granulation tissue as the primary factor (p=0.0130).

CONCLUSION

This novel identification of wound area and tissue types as a percentage, using digital planimetry, can play a crucial role in assisting nurses in decision-making related to the appropriate management of devitalized tissues. Furthermore, this measurements may facilitate the conducting of virtual wound consultations and offer valuable support in the development of protocols aimed at preventing infection and biofilm formation in the wound bed.

The Role of Sphingolipids and Sphingosine-1-phosphate-Sphingosine-1-phosphate-receptor Signaling in Psoriasis

Psoriasis is a long-lasting skin condition characterized by redness and thick silver scales on the skin's surface. It involves various skin cells, including keratinocytes, dendritic cells, T lymphocytes, and neutrophils. The treatments for psoriasis range from topical to systemic therapies, but they only alleviate the symptoms and do not provide a fundamental cure. Moreover, systemic treatments have the disadvantage of suppressing the entire body's immune system. Therefore, a new treatment strategy with minimal impact on the immune system is required. Recent studies have shown that sphingolipid metabolites, particularly ceramide and sphingosine-1-phosphate (S1P), play a significant role in psoriasis. Specific S1P-S1P-receptor (S1PR) signaling pathways have been identified as crucial to psoriasis inflammation. Based on these findings, S1PR modulators have been investigated and have been found to improve psoriasis inflammation. This review will discuss the metabolic pathways of sphingolipids, the individual functions of these metabolites, and their potential as a new therapeutic approach to psoriasis.

The Effect of Vitamin E Supplementation in Postmenopausal Women-A Systematic Review

Menopause is a physiological change in any woman. Nevertheless, its symptoms could be difficult to accept, and hormone therapy can be sometimes unattractive or contraindicated. Vitamin E components are phytoestrogens, so they are believed to be useful in some indications including menopause. This review aimed to assess the available evidence on the effectiveness of vitamin E in alleviating menopausal symptoms. The Pubmed/MEDLINE, Cochrane Library and Scopus databases were screened. All types of studies that assessed the effectiveness of vitamin E in alleviating menopausal symptoms were included. The PICO question was: "How does vitamin E supplementation affect menopausal symptom occurrence?" The PROSPERO ID number of this review is CRD42022328830. After quality assessment, 16 studies were included in the analysis. The studies were divided into three groups in which the influence of vitamin E on the genital syndrome of menopause, vasomotor symptoms and vascular and metabolic changes were assessed. Vitamin E influences postmenopausal hot flashes, vascular modulation, plasma lipid profile level and vaginal changes. Compared to vitamin E, estrogen administration leads to better clinical effects. Nevertheless, vitamin E might serve as additive to hormone therapy and its alternative in women with contraindications to estrogens. More quality data are necessary to draw final conclusions.