Background: Hair loss is linked to dysfunction of the growth (anagen), regression (catagen) and rest (telogen) phases of the hair follicle (HF) cycle.
Aims: To evaluate the effects of a Silybum marianum extract (SME), manganese PCA (MnPCA), and a Lespedeza capitata extract (LCE) on markers of hair growth and anchorage in human follicle dermal papilla cells (HFDPCs), and to investigate the ability of a topical serum containing these active ingredients to improve HF growth in an ex vivo human scalp skin model.
Methods: In HFDPCs, we assessed receptor tyrosine kinase phosphorylation and Wnt/β-catenin pathway activation; quantified versican, vascular endothelial growth factor (VEGF) and Dickkopf-1 (DDK1) secretion; and evaluated 5α-reductase (5αR) activity.
In a read-across assessment of the safety of genistein and daidzein in cosmetic products, additional information was required to account for differences in their systemic exposure after topical application in a typical body lotion formulation. Therefore, we measured the penetration and metabolism of two doses (3 and 30 nmoles/cm) of genistein and daidzein applied in ethanol and in a body formulation to fresh pig skin, fresh and frozen human skin, and PhenionFT models. Both chemicals readily penetrated all skin models when applied in ethanol.
View Article and Find Full Text PDFSun 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.
View Article and Find Full Text PDFJ Eur Acad Dermatol Venereol
August 2024
Background: The skin microbiota is known to be imbalanced in acne vulgaris, but the changes occurring during the early stages of acne onset remain poorly described.
Objectives: To characterize the skin microbiome of subclinical stages of acne in adults and adolescents.
Methods: The composition and diversity of the microbiota from non-lesional skin on the forehead of subjects with mild-to-moderate acne were compared to the ones from non-acne subjects.
J Eur Acad Dermatol Venereol
August 2024
Background: Acne vulgaris is a common chronic inflammatory disorder of the pilosebaceous unit, characterized by papules, pustules and/or nodules manifesting primarily on the face and/or upper back that can leave scars, post-inflammatory hyperpigmentation (PIH) and erythema (PIE).
Objective: To evaluate the anti-inflammatory properties of a protein-free sap extruded from Rhealba® oat plantlets and a Garcinia mangostana extract on Cutibacterium acnes-induced inflammation in vitro and assess the tolerability and efficacy of a dermocosmetic product containing these actives in subjects with mild-to-moderate acne.
Methods: Monocyte-derived dendritic cells (Mo-DCs) from acne patients were stimulated with a planktonic culture of C.
Intrinsic and extrinsic factors, including lifestyle and sun exposure, can contribute to cell senescence, which impairs skin homeostasis, that may in turn lead to skin aging. Senescent cells have a specific secretome, called the senescence-associated secretory phenotype (SASP) that includes MMPs, CXCLs and S100A8/9. Reducing the SASP with senotherapeutics is a promising strategy to reduce skin aging.
View Article and Find Full Text PDFThe skin surface lipids (SSLs) film, composed of sebum and keratinocyte membrane lipids, is crucial to the barrier function of the stratum corneum (SC). The first part of this study investigated the impact of solar radiation on the SC based on a novel hydration and dehydration approach using Raman spectroscopy. The SSLs were found to absorb solar light, and thus participate to the protection of the skin surface.
View Article and Find Full Text PDFThe mineral content of thermal spring water (TSW) applied to the skin surface can directly influence the skin barrier. Indeed, our previous study showed that Avène TSW (ATSW), a low mineral content thermal spring water, protects the stratum corneum from dehydration compared to a mineral-rich TSW (MR-TSW) and maintains skin surface ultrastructure. While many TSWs have been recognized to have beneficial effects on skin, little is known about their localized and specific effects on skin barrier biomechanics at the nanometric scale.
View Article and Find Full Text PDFIn recent years, interest is growing in the biological cutaneous effects of high-energy visible light (400-450 nm). In the present study, we explored the impact of blue light (BL) on the repair of pyrimidine dimers, the major class of premutagenic DNA damage induced by exposure to sunlight. We unambiguously demonstrate that the exposure of in vitro reconstructed human epidermis to environmentally relevant doses of BL strongly decreases the rate of repair of cyclobutane pyrimidine dimers and pyrimidine (6-4) pyrimidone photoproducts induced by a subsequent UVB irradiation.
View Article and Find Full Text PDFMicrobiol Spectr
January 2024
Characterization of the skin microbiome and metabolome across geography will help uncover the climate factors behind the prevalence of skin disorders and provide suggestions for skincare products for people living in different geographic regions.
View Article and Find Full Text PDFSunscreens have been shown to protect against UVR-induced DNA damage in human skin under laboratory conditions. We presently extended these observations to real-life conditions in volunteers after their ordinary exposure habits during summer holidays. Volunteers were randomly assigned to a control group and an educated group supplied with a SPF ≥50 sunscreen and receiving instructions for use.
View Article and Find Full Text PDFMatrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) has become an important tool for skin analysis, as it allows the simultaneous detection and localization of diverse molecular species within a sample. The use of and human skin models is costly and presents ethical issues; therefore, reconstructed human epidermis (RHE) models, which mimic the upper part of native human skin, represent a suitable alternative to investigate adverse effects of chemicals applied to the skin. However, there are few publications investigating the feasibility of using MALDI MSI on RHE models.
View Article and Find Full Text PDFA reconstructed human epidermal model (RHE) colonized with human microbiota and sebum was developed to reproduce the complexity of the skin ecosystem in vitro. The RHE model was exposed to simulated solar radiation (SSR) with or without SPF50+ sunscreen (with UVB, UVA, long-UVA, and visible light protection). Structural identification of discriminant metabolites was acquired by nuclear magnetic resonance and metabolomic fingerprints were identified using reverse phase-ultra high-performance liquid chromatography-high resolution mass spectrometry, followed by pathway enrichment analysis.
View Article and Find Full Text PDFThis study used Raman spectroscopy to develop a new approach to evaluate the effects of solar radiation on the stratum corneum (SC). The method measures the SC's hydration and dehydration kinetics by calculating the vOH/vCH ratio to monitor the relative water content during the drying process. The study also investigated the role of skin surface lipids (SSLs) in protecting the SC from solar radiation.
View Article and Find Full Text PDFObjective: Skin ageing is linked to the accumulation of senescent cells and a "senescence-associated secretory phenotype" (SASP). SASP factors include chemokines, cytokines, and small extracellular vesicles (EVs) containing miRNAs. We characterized SASP profile markers in normal human dermal fibroblasts (HDFs) and evaluated the effect of Haritaki fruit extract on these senescence markers.
View Article and Find Full Text PDFTriglycerides (TGs) are one of the main components of the glycerolipid family. Their main task in cells is to store excess fatty acids. TG energy storage is mainly concentrated in adipocytes.
View Article and Find Full Text PDFIntroduction: The stratum corneum (SC) matrix is composed of free fatty acids, cholesterol, and ceramides (CERs), which play a key role in the skin barrier function. Changes in the composition and content of skin lipids will affect the function of the skin barrier. The effect of a glycerol/petrolatum-based emollient (G/P-emollient) cream on the lipid profiles of isolated ex vivo human SC and the SC of a reconstructed human epidermis (RHE) model was measured.
View Article and Find Full Text PDFBackground: Acne is a multifactorial chronic inflammatory disease of the pilosebaceous unit, where Cutibacterium acnes plays a main role. Recent papers demonstrated that specific C. acnes phylotypes were correlated with the severity of inflammatory acne and reported a specific loss of C.
View Article and Find Full Text PDFIntroduction: Acne is a multifactorial inflammatory disease of the pilosebaceous unit in which Cutibacterium acnes is one of the main triggers. A strong predominance of C. acnes phylotype IA1 is present in acne skin with higher biofilm organization and virulence, promoting local immuno-inflammation, especially the Th17 pathway.
View Article and Find Full Text PDFAcne vulgaris is a common chronic inflammatory skin disease of the pilosebaceous units. Four factors contribute to acne: hyperseborrhea and dysseborrhea, follicular hyperkeratinisation, skin microbiome dysbiosis and local immuno-inflammation. Recent key studies have highlighted a better understanding of the important role of Cutibacterium acnes (C.
View Article and Find Full Text PDFLiquid chromatography-mass spectrometry (LC-MS)-based metabolomics usually combines hydrophilic interaction liquid chromatography (HILIC) and reversed-phase (RP) chromatography to cover a wide range of metabolomes, requiring both significant sample consumption and analysis time for separate workflows. We developed an integrated workflow enabling the coverage of both polar and nonpolar metabolites with only one injection of the sample for each ionization mode using heart-cutting trapping to combine HILIC and RP separations. This approach enables the trapping of some compounds eluted from the first chromatographic dimension for separation later in the second dimension.
View Article and Find Full Text PDFUV-induced formation of photoproducts in DNA is a major initiating event of skin cancer. Consequently, many analytical tools have been developed for their quantification in DNA. In the present work, we extended our previous liquid chromatography-mass spectrometry method to the quantification of the short DNA fragments containing photoproducts that are released from cells by the repair machinery.
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