New Plant Extracts Exert Complementary Anti-Hair Loss Properties in Human In Vitro and Ex Vivo Models.

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.

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.

Characterization of the forehead skin microbiome in the early phase of acne.

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.

Senomorphic activity of a combination of niacinamide and hyaluronic acid: correlation with clinical improvement of skin aging.

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.

Effect of a low-mineralized thermal spring water on skin barrier mechanical properties using atomic force microscopy.

The 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.

Blue light impairs the repair of UVB-induced pyrimidine dimers in a human skin model.

In 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.

Multi-omics approach to understand the impact of sun exposure on an in vitro skin ecosystem and evaluate a new broad-spectrum sunscreen.

A 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.

Generating Functional and Highly Proliferative Melanocytes Derived from Human Pluripotent Stem Cells: A Promising Tool for Biotherapeutic Approaches to Treat Skin Pigmentation Disorders.

Melanocytes are essential for skin homeostasis and protection, and their loss or misfunction leads to a wide spectrum of diseases. Cell therapy utilizing autologous melanocytes has been used for years as an adjunct treatment for hypopigmentary disorders such as vitiligo. However, these approaches are hindered by the poor proliferative capacity of melanocytes obtained from skin biopsies.

Reduction of senescence-associated secretory phenotype and exosome-shuttled miRNAs by Haritaki fruit extract in senescent dermal fibroblasts.

Objective: 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.

Evaluation of a Novel Skin Emollient Cream on Skin Lipidome and Lipid Organization.

Introduction: 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.

Change in Cutibacterium acnes phylotype abundance and improvement of clinical parameters using a new dermocosmetic product containing Myrtus communis and Celastrol enriched plant cell culture extracts in patients with acne vulgaris.

Background: 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.

Myrtus communis and Celastrol enriched plant cell culture extracts control together the pivotal role of Cutibacterium acnes and inflammatory pathways in acne.

Introduction: 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.

Recent advances in understanding inflammatory acne: Deciphering the relationship between Cutibacterium acnes and Th17 inflammatory pathway.

Acne 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.

Formulation of a new broad-spectrum UVB + UVA and blue light SPF50 sunscreen containing Phenylene Bis-Diphenyltriazine (TriAsorB), an innovative sun filter with unique optical properties.

Accumulating evidence from numerous comprehensive studies has demonstrated that blue light, in particular high-energy visible light, can exert a range of harmful effects on skin cells. These forms of radiation are now known to be able to trigger oxidation reactions, DNA damage, erythema and pigmentary changes, and may also be associated with photoaging. Sunscreens protecting the skin from only ultraviolet (UV)-B and UVA rays can therefore no longer be regarded as sufficient to help prevent skin damage from sunlight, and products containing filters that can provide broad-spectrum photoprotection are required.

MS imaging and absorption methods visualizing sun filter skin spatial distribution and penetration.

Sunscreens must now be effective in protecting skin from ultraviolet, as well as visible/infrared radiation. Here, TriAsorB, a new broad-spectrum sun filter, was formulated with three other sunscreens and their distribution on human skin was studied using a standard penetration protocol and two novel mass spectrometry imaging techniques: atmospheric pressure matrix assisted laser desorption ionization (AP-MALDI) coupled to high resolution mass spectrometry and time of flight - secondary ion mass spectrometry (ToF-SIMS). The standard penetration protocol showed that sun filters absorption was very low, with most of the dose recovered at the surface (none entered the receptor fluid).

In vitro characterization and clinical evaluation of skin hydration by two formulations mimicking the skin's natural components.

Background: We have developed innovative base formulations that were designed to mimic the skin with respect to its components and galenic structure. Components include water, proteins, lipids, sugars and minerals.

Objectives: We characterized formulations and their skin penetration using in vitro methods and evaluated their impact on skin hydration in a clinical trial.

Specific protection of sensitive skin against environmental stress by maintenance and improvement of barrier function.

Background: Sensitive skin is a common condition that can severely impact quality of life. Several mechanisms are thought to be involved, including those affecting the skin barrier function, hydration and skin innervation.

Objectives: To investigate the benefit of cream and balm formulations dedicated to sensitive skin and containing Aquaphilus dolomiae extract-G3 (ADE-G3) on skin barrier functions (lipid composition, pH, TEWL), as well as protective responses to dry and pollution stresses.

Clinical evaluation of anaesthetic-like effect of two dermocosmetic formulations containing Aquaphilus dolomiae extract-G3 in subjects with sensitive facial skin.

Background: Sensitive skin is a common condition of hyper-reactivity to external stimuli, e.g. heat or abrasion.

Ascorbic acid 2-glucoside: An ascorbic acid pro-drug with longer-term antioxidant efficacy in skin.

Objective: Deleterious effects of pollutants and ultraviolet radiation on the skin can be attenuated using formulations containing antioxidants. However, these have disadvantages, including chemical instability, photodegradation, poor bioavailability or biological activity. Here, two commercial formulations were evaluated: one optimized to stabilize and deliver ascorbic acid (AA) at 15% and the other containing a glucoside form of AA, namely ascorbic acid 2-glucoside (AA2G), at 1.

Phenylene Bis-Diphenyltriazine (TriAsorB), a new sunfilter protecting the skin against both UVB + UVA and blue light radiations.

Sunlight induces actinic keratosis, skin cancers and photoaging. Photoprotection is thus a major issue in public health to prevent the harmful effects of solar ultraviolet (UV) radiations. Recent data have shown that the visible (VIS) and infrared (IR) radiations can lead to skin damage by oxidative stress, suggesting that a balanced protection across the entire spectrum of sunlight is necessary to prevent cutaneous alterations.

Safety assessment of cosmetics by read across applied to metabolomics data of in vitro skin and liver models.

As a result of the cosmetics testing ban, safety evaluations of cosmetics ingredients must now be conducted using animal-free methods. A common approach is read across, which is mainly based on structural similarities but can also be conducted using biological endpoints. Here, metabolomics was used to assess biological effects to enable a read across between a candidate cosmetic ingredient, DIV665, only studied using in vitro assays, and a structurally similar reference compound, PA102, previously investigated using traditional in vivo toxicity methods.

Sustained effect of two antioxidants (oxothiazolidine and δ-tocopheryl glucoside) for immediate and long-term sun protection in a sunscreen emulsion based on their different penetrating properties.

Objective: We investigated the dermal bioavailability and antioxidative properties of a sunscreen formulation containing two antioxidants, oxothiazolidine (OTZ) and δ-tocopheryl glucoside (DTG). OTZ reacts directly with reactive oxygen species to form taurine, while DTG is metabolized in δ-tocopherol to achieve antioxidative activities.

Methods: After topical application to a hair follicle-derived reconstructed human epidermis (RHE) model, followed by solar-simulated radiation, kinetics of bioavailability and antioxidative responses were measured over 24 h.

Comprehensive characterization of the structure and properties of human stratum corneum relating to barrier function and skin hydration: modulation by a moisturizer formulation.

The stratum corneum (SC) is key in the maintenance of the biomechanical barrier and hydration of skin. Our previous investigations showed beneficial effects of a combination of emollients on water capture and retention and protein and lipid organization, all of which are linked to dryness and dry skin damage. Here, we show how a formulation containing an emollient combination ("Trio") and its basal formulation (placebo) impacted the descriptors of SC hydration in SC layers.

Protective effect of Aquaphilus dolomiae extract-G1, ADE-G1, on tight junction barrier function in a Staphylococcus aureus-infected atopic dermatitis model.

Background: Atopic dermatitis (AD) is a common skin disease characterized by recurrent pruritic inflammatory skin lesions and defects of the skin barrier. Bacterial infection with Staphylococcus aureus contributes to increased severity of AD by compromising the barrier further. A microorganism component of Avène Thermal Spring Water, Aquaphilus dolomiae, is thought to contribute to some of its beneficial effects to skin, eg AD alleviation.

Protective properties of Avène Thermal Spring Water on biomechanical, ultrastructural and clinical parameters of human skin.

Background: Thermal Spring Water (TSW) has been recognized to have beneficial effects on skin; however, the mechanisms underlying these are not completely elucidated.

Aims: We compared the effects of Avène TSW with mineral-rich (MR) TSW on the biomechanical properties of the skin using mechanistic ex vivo assays and clinical studies.

Methods: Ex vivo studies included the effect of both TSWs on the structure of the surface of human skin explants using scanning electron microscopy (SEM); mineral elemental content on the skin surface using SEM coupled to energy dispersing X-ray spectroscopy; and the stress properties of the stratum corneum (SC) when exposed to dehydration.