Analysis on the difference of skin surface lipids during blue light therapy for acne by lipidomics

Current Insights on Lipidomics in Dermatology: A Systematic Review

Inflammatory dermatoses and lipid disturbances are interrelated, especially owing to chronic inflammatory conditions. This study aimed to investigate recent findings about lipidomic and dermatologic diseases as well as on the sampling techniques developed to study lipidomics in vivo and analytical and statistical approaches employed. A systematic review was designed using the search algorithm (lipidomics) AND (skin OR dermatology OR stratum corneum OR sebum OR epidermis), following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search identified 1013 references, and finally, only 48 were selected, including a total of 2651 participants with a mean age of 34.13 ± 16.28 years. The dermatologic diseases evaluated were atopic dermatitis, acne, psoriasis, hidradenitis suppurativa, and other skin diseases. Sebutape was the primary sampling technique for lipidomics research. Most of the studies performed untargeted profiling through liquid chromatography with tandem mass spectrometry statistically analyzed with principal component analysis, orthogonal partial least-squares discriminate analysis, heatmap, and volcano plot models. The most consulted databases were LIPIDMAPS Structure Database, MetaboAnalyst, and Human Metabolome Database. A large heterogeneity of lipidomic and lipid metabolism profiles was observed in patients with skin diseases. Skin lipidomic analysis is valuable in exploring skin disease and has ample translational potential.

Emerging Innovations in Acne Management: A Focus on Non-Pharmacological Therapeutic Devices

Acne is a chronic inflammatory condition affecting the sebaceous glands, with approximately 80% of individuals experiencing it at some point in their lives. Among adolescents, the incidence is reported to exceed 85%. The disease can significantly impact both physical and emotional aspects of a person's quality of life, leading to permanent scarring, poor self-image, depression, and anxiety. The standard first-line treatment for acne vulgaris includes conventional pharmacological approaches such as keratolytics, topical or oral antibiotics, retinoids, and hormonal agents. However, these treatments are not universally effective due to patient noncompliance, adverse drug effects, and the emergence of antibiotic resistance in Cutibacterium acnes, often resulting in high rates of recurrence. Consequently, non-pharmacological therapies have been developed as safe and effective alternatives or supplements to pharmacological treatment. These non-pharmacological approaches can serve as standalone treatment modalities, adjuncts to pharmacological therapy, or maintenance treatments. Current literature lacks comprehensive data on the classification of these non-pharmacological treatment options. This paper aims to provide a brief overview of recent research on the practical applications and potential mechanisms of non-pharmacological therapies for both acne and acne scars. Through elucidating the distinct mechanisms and therapeutic roles of these treatments, we aim to assist dermatologists and other healthcare providers in formulating more effective disease management strategies, thereby encouraging further research in this area.

Multi-omics analysis to evaluate the effects of solar exposure and a broad-spectrum SPF50+ sunscreen on markers of skin barrier function in a skin ecosystem model

Sun exposure induces major skin alterations, but its effects on skin metabolites and lipids remain largely unknown. Using an original reconstructed human epidermis (RHE) model colonized with human microbiota and supplemented with human sebum, we previously showed that a single dose of simulated solar radiation (SSR) significantly impacted the skin metabolome and microbiota. In this article, we further analyzed SSR-induced changes on skin metabolites and lipids in the same RHE model. Among the significantly altered metabolites (log2-fold changes with p ≤ 0.05), we found several natural moisturizing factors (NMFs): amino acids, lactate, glycerol, urocanic acid, pyrrolidone carboxylic acid and derivatives. Analyses of the stratum corneum lipids also showed that SSR induced lower levels of free fatty acids and higher levels of ceramides, cholesterols and its derivatives. An imbalance in NMFs and ceramides combined to an increase of proinflammatory lipids may participate in skin permeability barrier impairment, dehydration and inflammatory reaction to the sun. Our skin model also allowed the evaluation of an innovative ultraviolet/blue light (UV/BL) broad-spectrum sunscreen with a high sun protection factor (SPF50+). We found that using this sunscreen prior to SSR exposure could in part prevent SSR-induced alterations in NMFs and lipids in the skin ecosystem RHE model.

Effects of Light and Laser Therapies on the Microecosystem of Sebaceous Glands in Acne Treatment

BACKGROUND

Acne vulgaris (acne) is one of the most common skin diseases with complex pathogenesis. Numerous studies have shown that the microecosystem of sebaceous glands and Cutibacterium acnes play key roles in its pathogenesis. Antibiotics targeting C. acnes have been widely used in acne treatment, but the growing prevalence of antibiotic resistance has become alarming. Further research into the microecosystem of sebaceous glands and the role of specific C. acnes phylotypes in acne pathogenesis has led to a paradigm shift in acne treatment. Currently, non-antibiotic therapies such as light therapy and laser therapy are becoming increasingly popular, opening up new opportunities in acne management.

METHODS

Studies on the microecosystem of sebaceous glands associated with acne and the effects of light and laser therapies on the microecosystem in acne treatment were retrieved from the PubMed database.

RESULTS

Dysbiosis of the microecosystem of the pilosebaceous unit is closely related to the pathogenesis of acne. Light and laser therapies have an impact on the microecosystem of the pilosebaceous unit in acne treatment.

CONCLUSIONS

Light and laser therapies are the popular alternative options in acne treatment. The mechanisms of their effect on the microecosystem of sebaceous glands are not completely clear and require further research, especially for laser therapy.

The impact of energy-based devices on sebum in acne vulgaris: A systematic review

BACKGROUND

Acne vulgaris (AV) is a widespread inflammatory skin condition associated with increased sebum production, abnormal keratinization, bacterial overgrowth, and inflammation. Overactive sebaceous glands (SGs) produce excess sebum, promote Cutibacterium acnes growth, and affect acne development. Energy-based treatments (EBDs), including light therapy, photodynamic therapy (PDT), lasers, and radiofrequency (RF) devices, have emerged as effective treatment options. As the use of EBDs becomes more widespread, it is imperative to understand their effects on skin parameters, such as sebum, in AV.

METHODS

Searches were conducted in Embase, PubMed, Web of Science, and the Cochrane Library. The studies included were randomized and nonrandomized trials on facial AV that used EBDs and featured objective casual sebum level (CSL) measurements via Sebumeter. Data synthesis involved percentage reductions in CSL at follow-ups compared to baseline.

RESULTS

Twenty-three studies were analyzed. PDT and RF consistently reduced CSL by 30%-40% and 30%-35%, respectively. Laser therapy showed lesser reductions, whereas light therapy varied significantly and studies had a high risk of bias. All EBD therapies were more effective than no treatment and PDT was superior to light monotherapy. Laser therapy combined with fractional microneedling radiofrequency (FMR) or as a standalone was more effective than laser alone.

CONCLUSION

Noninvasive sebum measurement provides valuable insights into AV treatment efficacy. PDT, lasers, especially the 1450-nm diode laser, and FMR are promising for reducing sebum. Standardization of measurement techniques and further research are vital for enhancing treatment personalization, reducing side effects, and improving AV management.

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.

Comparative study of melasma in patients before and after treatment based on lipomics

BACKGROUND

Skin barrier alterations play a crucial function in melasma development. Past researches have demonstrated variations in lipid content between the epidermis of melasma lesions and normal tissues, along with the varied expression of lipid-related genes in melasma. This study aimed to analyze the lipidome profiles of skin surface lipids (SSL) in patients with melasma before and after treatment to understand associated abnormalities.

METHODS

Melasma was treated with tranexamic acid orally and hydroquinone cream topically. Disease was assessed using the Melasma Area and Severity Index (MASI), and the impact to life was evaluated with Melasma Quality of Life (MELASQoL) score. Epidermal melanin particles were observed using reflection confocal microscopy (RCM), whereas epidermal pigment and blood vessel morphology were observed using dermoscopy, and SSL samples were collected. Specific information regarding alterations in lipid composition was obtained through multivariate analysis of the liquid chromatography-mass spectrometry data.

RESULTS

After treatment, patients with melasma exhibited decreased MASI and MELASQoL scores (P < 0.001); RCM revealed reduced melanin content in the lesions, and dermoscopy revealed fewer blood vessels. Fifteen lipid subclasses and 382 lipid molecules were identified using lipidomic assays. The expression levels of total lipids, phosphatidylcholine, and phosphatidylethanolamine in the melasma lesions decreased after treatment (P < 0.05).

CONCLUSION

This study revealed alterations in the SSL composition after effective melasma treatment, suggesting a compensatory role for lipids in melasma barrier function. The mechanism involving SSL and the lipid barrier, which influences melasma's occurrence, needs further elucidation.

Chewing the fat: How lipidomics is changing our understanding of human health and disease in 2022

Lipids are biological molecules that play vital roles in all living organisms. They perform many cellular functions, such as 1) forming cellular and subcellular membranes, 2) storing and using energy, and 3) serving as chemical messengers during intra- and inter-cellular signal transduction. The large-scale study of the pathways and networks of cellular lipids in biological systems is called "lipidomics" and is one of the fastest-growing omics technologies of the last two decades. With state-of-the-art mass spectrometry instrumentation and sophisticated data handling, clinical studies show how human lipid composition changes in health and disease, thereby making it a valuable medium to collect for clinical applications, such as disease diagnostics, therapeutic decision-making, and drug development. This review gives a comprehensive overview of current workflows used in clinical research, from sample collection and preparation to data and clinical interpretations. This is followed by an appraisal of applications in 2022 and a perspective on the exciting future of clinical lipidomics.

No skin off your back: the sampling and extraction of sebum for metabolomics

INTRODUCTION

Sebum-based metabolomics (a subset of "sebomics") is a developing field that involves the sampling, identification, and quantification of metabolites found in human sebum. Sebum is a lipid-rich oily substance secreted by the sebaceous glands onto the skin surface for skin homeostasis, lubrication, thermoregulation, and environmental protection. Interest in sebomics has grown over the last decade due to its potential for rapid analysis following non-invasive sampling for a range of clinical and environmental applications.

OBJECTIVES

To provide an overview of various sebum sampling techniques with their associated challenges. To evaluate applications of sebum for clinical research, drug monitoring, and human biomonitoring. To provide a commentary of the opportunities of using sebum as a diagnostic biofluid in the future.

METHODS

Bibliometric analyses of selected keywords regarding skin surface analysis using the Scopus search engine from 1960 to 2022 was performed on 12th January 2023. The published literature was compartmentalised based on what the work contributed to in the following areas: the understanding about sebum, its composition, the analytical technologies used, or the purpose of use of sebum. The findings were summarised in this review.

RESULTS

Historically, about 15 methods of sampling have been used for sebum collection. The sample preparation approaches vary depending on the analytes of interest and are summarised. The use of sebum is not limited to just skin diseases or drug monitoring but also demonstrated for other systemic disease. Most of the work carried out for untargeted analysis of metabolites associated with sebum has been in the recent two decades.

CONCLUSION

Sebum has a huge potential beyond skin research and understanding how one's physiological state affects or reflects on the skin metabolome via the sebaceous glands itself or by interactions with sebaceous secretion, will open doors for simpler biomonitoring. Sebum acts as a sink to environmental metabolites and has applications awaiting to be explored, such as biosecurity, cross-border migration, localised exposure to harmful substances, and high-throughput population screening. These applications will be possible with rapid advances in volatile headspace and lipidomics method development as well as the ability of the metabolomics community to annotate unknown species better. A key issue with skin surface analysis that remains unsolved is attributing the source of the metabolites found on the skin surface before meaningful biological interpretation.