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Clinical efficacy of a multilamellar cream on skin physiology and microbiome in an epidermal stress model : A controlled double-blinded study (Part I) / Joachim W. Fluhr in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 46, N° 4 (08/2024)
[article]
Titre : Clinical efficacy of a multilamellar cream on skin physiology and microbiome in an epidermal stress model : A controlled double-blinded study (Part I) Type de document : texte imprimé Auteurs : Joachim W. Fluhr, Auteur ; Peter Menzel, Auteur ; Rolf Schwarzer, Auteur ; Dessyslava G. Nikolaeva, Auteur ; Razvigor Darlenski, Auteur ; Martin Albrecht, Auteur Année de publication : 2024 Article en page(s) : p. 566-577 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Barrière cutanée
Composés lamellaires
Dermo-cosmétologie
Emollients
Formulation (Génie chimique)
Formulation (génie chimique) -- Stabilité
Microbiologie
Microbiome cutané
Peau -- Physiologie
Peau -- Soins et hygiène
pHIndex. décimale : 668.5 Parfums et cosmétiques Résumé : - INTRODUCTION : 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).
- MATERIALS AND METHODS : 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.
- RESULTS : 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.
- DISCUSSION AND CONCLUSION : 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.Note de contenu : - MATERIALS AND METHODS : Study approval and participants - Study design - Skin physiology parameters - Test formulations - Microbiome assessment - Sequence analysis - Statistical analysis
- RESULTS : Participant characterization and measuring conditions - Skin physiology - MicrobiomeDOI : https://doi.org/10.1111/ics.12950 En ligne : https://drive.google.com/file/d/1U0a6kkQUzXUuQE9keMO6rSFr2mHLmLK5/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41355
in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE > Vol. 46, N° 4 (08/2024) . - p. 566-577[article]Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire How do the skin barrier and microbiome adapt to the extra-uterine environment after birth ? Implications for the clinical practice / Razvigor Darlenski in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 45, N° 3 (06/2023)
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Titre : How do the skin barrier and microbiome adapt to the extra-uterine environment after birth ? Implications for the clinical practice Type de document : document électronique Auteurs : Razvigor Darlenski, Auteur ; Joachim W. Fluhr, Auteur Année de publication : 2023 Article en page(s) : p. 288-298 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Barrière cutanée
CéramidesUn céramide est un sphingolipide résultant de la combinaison d'un acide gras avec la sphingosine via une liaison amide. On trouve de telles molécules en abondance dans les membranes cellulaires, où elles entrent notamment dans la constitution des sphingomyélines. Les céramides ne jouent pas qu'un rôle structurel dans les membranes biologiques, et peuvent également revêtir des fonctions de signalisation lipidique. Leurs actions les mieux comprises vont de la différenciation cellulaire à la mort cellulaire programmée (apoptose) en passant par la prolifération cellulaire.
Les acides gras qui les constituent ont généralement un nombre pair (de 16 à 24) d'atomes de carbone, sont saturés ou monoinsaturés, et sont souvent α-hydroxylés.
La plupart des céramides n'existent pas à l'état naturel si ce n'est comme précurseurs de la biosynthèse des sphingolipides par une réaction d'addition sur la fonction alcool primaire de la sphingosine. (Wikipedia)
Couche cornée
Dermatologie pédiatrique
Enfants
Hydratation
Lactique, AcideL'acide lactique est un acide organique qui joue un rôle dans divers processus biochimiques. Un lactate est un sel de cet acide. Contrairement à ce que peut laisser penser son nom, l'acide lactique n'est pas présent uniquement dans le lait, mais également dans le vin, certains fruits et légumes, et dans les muscles.
L'acide lactique est un acide alpha hydroxylé, sa formule chimique est C3H6O3 et sa structure se reflète dans son nom systématique, l'acide 2-hydroxypropanoïque.
MicrobiomeLe microbiome (du grec micro = petit et bios = vie) est l'« aire biotique » (aire de vie) du microbiote, le mot microbiote désignant ici les espèces autrefois groupées sous le terme « microflore », c'est-à -dire celles qui prédominent et/ou sont durablement adaptées à la surface et à l'intérieur d'un organisme vivant.
Nourrissons
Peau -- analyse
Perte insensible en eau
pHIndex. décimale : 668.5 Parfums et cosmétiques Résumé : The multiple protective functions of the skin derive from the interactions between epithelial skin and immune cells as well as the commensal microbiota. Developed in the last trimester of intra-uterine life, the skin barrier adapts dynamically after birth. Specific differences in the structure and physiology have been disclosed between infant and adult skin. The stratum corneum of infants is thinner and structured by thicker corneocytes with a more anisotropic surface in comparison to adult skin. Lower levels of the natural moisturizing factor and its constituents, together with the increased protease activity in the epidermis result in dry baby skin and ongoing adaptation of the desquamation to the extra-uterine environment. Infant epidermis is characterized by an accelerated proliferation rate and clinically competent permeability barrier in term neonates, despite the higher baseline values of transepidermal water loss in infants. The skin surface of newborns is less acidic, which could increase susceptibility to diaper and atopic dermatitis. Immediately after birth, skin is colonized by commensal bacteria—a process dependent on the mode of delivery and of major importance for the maturation of the immune system. Skin bacterial diversity and dysbiosis have been related to different pathology such as atopic and seborrheic dermatitis. This paper focuses on the ongoing structural, functional and biochemical adaptation of the human skin barrier after birth. We discuss the interactions on the ‘skin barrier/ microbiota/ immune system’ axis and their role in the development of competent functional integrity of the epidermal barrier. Note de contenu : - STRUCTURAL ADAPTATION AFTER BIRTH
- BIOCHEMICAL COMPOSITION ADAPTATION
- FUNCTIONAL ADAPTATION AFTER BIRTH : Permeability barrier evaluation by TEWL measurement - Hydration and water-handling properties of stratum corneum - Acidic skin surface or the so-called 'acid mantle' - Sebum secretion - Eccrine sweating - Cutaneous blood flow and colour
SKIN MICROBIOME AND ANTI-MICROBIAL DEFENCEDOI : https://doi.org/10.1111/ics.12844 En ligne : https://drive.google.com/file/d/1vDabEcPNeLrCQAQ7Is7w0pFgG3ZF20X2/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39561
in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE > Vol. 45, N° 3 (06/2023) . - p. 288-298[article]Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire Impact of multilamellar formulations on stratum corneum lipid organization and epidermal lipid barrier enhancement (Part II) / Joachim W. Fluhr in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 46, N° 4 (08/2024)
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Titre : Impact of multilamellar formulations on stratum corneum lipid organization and epidermal lipid barrier enhancement (Part II) Type de document : texte imprimé Auteurs : Joachim W. Fluhr, Auteur ; Razvigor Darlenski, Auteur ; Stephan Daehnhardt-Pfeiffer, Auteur ; Martin Albrecht, Auteur Année de publication : 2024 Article en page(s) : p. 578-589 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Barrière cutanée
Composés lamellaires
Cosmétiques
Dermo-cosmétologie
Emollients
LécithineLa phosphatidylcholine est plus connue sous le nom lécithine.
Au sens le plus strict, la lécithine désigne uniquement les phosphatidylcholines c'est-à -dire un lipide formé à partir d'une choline, d'un phosphate, d'un glycérol et de deux acides gras (figure). Dans ce contexte, il serait plus juste de parler des lécithines, car il ne s'agit pas d'une seule molécule mais d'un groupe dont la composition en acide gras varie d'une molécule à l'autre. Ainsi, les lécithines vont adopter diverses couleurs selon leur composition : du jaune, pour la lécithine végétale, au brun, pour la lécithine de poisson.
Le terme de lécithine est aussi utilisé par extension pour désigner l'ensemble des phospholipides extraits du vivant (par exemple le soja), dans la mesure où ils sont majoritairement constitués de phosphatidylcholine.
Microscopie électronique en transmission
Peau -- Soins et hygiène
pHIndex. décimale : 668.5 Parfums et cosmétiques Résumé : - INTRODUCTION : 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.
- METHODS : 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.
- RESULTS : 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.
- DISCUSSION : 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.
- CONCLUSION : 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.Note de contenu : - MATERIALS AND METHODS : Cream formulation - Ultrastructure analysis of cream vehicle - Ultrastructure analysis of treated skin - Lipid analysis by HPTLC - Study population - Statistics
- RESULTS : Lipid morphology of the multilamellar formulation - Enhanced lipid bilayers in vivo by short-term application - Enhanced lipid bilayers in vivo in a 14-day application - Improved composition of critical barrier lipids in vivo in a 14-day applicationDOI : https://doi.org/10.1111/ics.12971 En ligne : https://drive.google.com/file/d/1e6txw5orQ1eu7htXGVIdPivCYwQt5sbh/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41356
in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE > Vol. 46, N° 4 (08/2024) . - p. 578-589[article]Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire