Ceramide liposomes for skin barrier recovery: A novel formulation based on natural skin lipids

Skin may be affected by many disorders that can be treated by topical applications of drugs on the action site. With the advent of nanotechnologies, new efficient delivery systems have been developed. Particularly, lipid-based nanosystems such as liposomes, ethosomes, transferosomes, solid lipid nanoparticles, nanostructured lipid carriers, cubosomes, and monoolein aqueous dispersions have been proposed for cutaneous application, reaching in some cases the market or clinical trials. This review aims to provide an overview of the different lipid-based nanosystems, focusing on their use for topical application. Particularly, biocompatible nanosystems able to dissolve lipophilic compounds and to control the release of carried drug, possibly reducing side effects, are described. Notably, the rationale to topically administer antioxidant molecules by lipid nanocarriers is described. Indeed, the structural similarity between the nanosystem lipid matrix and the skin lipids allows the achievement of a transdermal effect. Surely, more research is required to better understand the mechanism of interaction between lipid-based nanosystems and skin. However, this attempt to summarize and highlight the possibilities offered by lipid-based nanosystems could help the scientific community to take advantage of the benefits derived from this kind of nanosystem.

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Systematic Investigation of the Effect of Non-Ionic Emulsifiers on Skin by Confocal Raman Spectroscopy—A Comprehensive Lipid Analysis

Pharmaceutics ◽

10.3390/pharmaceutics12030223 ◽

2020 ◽

Vol 12 (3) ◽

pp. 223 ◽

Cited By ~ 4

Author(s):

Yali Liu ◽

Dominique Jasmin Lunter

Keyword(s):

Raman Spectroscopy ◽

Polyethylene Glycol ◽

Lipid Content ◽

Deep Understanding ◽

Skin Barrier ◽

Fatty Acid Esters ◽

Skin Barrier Function ◽

Confocal Raman Spectroscopy ◽

Skin Lipids ◽

Confocal Raman

Non-ionic emulsifiers are commonly found in existing pharmaceutical and cosmetic formulations and have been widely employed to enhance the penetration and permeation of active ingredients into the skin. With the potential of disrupting skin barrier function and increasing fluidity of stratum corneum (SC) lipids, we herein examined the effects of two kinds of non-ionic emulsifiers on intercellular lipids of skin, using confocal Raman spectroscopy (CRS) with lipid signals on skin CRS spectrum. Non-ionic emulsifiers of polyethylene glycol alkyl ethers and sorbitan fatty acid esters were studied to obtain a deep understanding of the mechanism between non-ionic emulsifiers and SC lipids. Emulsifier solutions and dispersions were prepared and applied onto excised porcine skin. Water and sodium laureth sulfate solution (SLS) served as controls. SC lipid signals were analysed by CRS regarding lipid content, conformation and lateral packing order. Polyethylene glycol (PEG) sorbitan esters revealed no alteration of intercellular lipid properties while PEG-20 ethers appeared to have the most significant effects on reducing lipid content and interrupting lipid organization. In general, the polyoxyethylene chain and alkyl chain of PEG derivative emulsifiers might indicate their ability of interaction with SC components. HLB values remained critical for complete explanation of emulsifier effects on skin lipids. With this study, it is possible to characterize the molecular effects of non-ionic emulsifiers on skin lipids and further deepen the understanding of enhancing substance penetration with reduced skin barrier properties and increased lipid fluidity.

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Revealing the Correlation between Altered Skin Lipids Composition and Skin Disorders

Cosmetics ◽

10.3390/cosmetics8030088 ◽

2021 ◽

Vol 8 (3) ◽

pp. 88

Author(s):

Katerina Drakou ◽

Andrea Tsianni ◽

Faye Vrani ◽

Valia Kefala ◽

Efstathios Rallis

Keyword(s):

Atopic Dermatitis ◽

Lipid Composition ◽

Acne Vulgaris ◽

Skin Barrier ◽

The Body ◽

Microbiome Composition ◽

Skin Lipids ◽

Key Players ◽

Dermatological Disorders

Human skin layers serve as a barrier between the body and the environment, by preventing water loss and blocking the entry of chemicals, allergens, and microbes. Recent data showed that skin lipids are vital ‘key players’ of several functions and mechanisms performing in the skin, such as, barrier function and microbiome composition. Abnormalities in lipid composition have been observed in inflammatory cutaneous diseases with a disrupted skin barrier. This review aims to demonstrate the fundamental role of keratinocytes, sebocytes, and microbiome-derived lipids in the maintenance of the skin barrier. Furthermore, it would reveal the correlation between altered skin lipids’ composition, microbiome, and the occurrence of certain dermatological disorders such as acne vulgaris, atopic dermatitis, psoriasis, and rosacea.

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Bacterial invasion across the human skin barrier – mechanisms and ensuing tissue degradation.

10.1101/2021.10.06.463452 ◽

2021 ◽

Author(s):

Zachary W Lipsky ◽

Marissa K Patsy ◽

Claudia N. H. Marques ◽

Guy K German

Keyword(s):

Human Skin ◽

Skin Barrier ◽

Theoretical Models ◽

Structural Defects ◽

Bacterial Invasion ◽

Outermost Layer ◽

Skin Lipids ◽

Bacterial Penetration ◽

Tissue Degradation ◽

Temperature Controlled

Atopic Dermatitis (AD) is associated with a deficiency of skin lipids, increased populations of Staphylococcus aureus in the microbiome, and structural defects in the stratum corneum (SC), the outermost layer of human skin. However, the pathogenesis of AD is ambiguous as it is unclear whether observed changes are the result of AD or contribute to the pathogenesis of the disease. Previous studies have shown that S. aureus is capable of permeating across isolated human SC tissue when lipids are depleted to levels consistent with AD conditions. In this study, we expand upon this discovery to determine the mechanisms of bacterial penetration into the SC barrier. Specifically, we establish whether bacteria are permeating intercellularly, between corneocytes, or employing a combination pathway of both inter- and intra-cellular travel. The mechanical implications of bacterial invasion, lipid depletion, and media immersion are also evaluated using a newly developed, physiologically relevant, temperature-controlled drip chamber. Results reveal that S. aureus can be internalized by corneocytes, indicating transcellular movement through the tissue during permeation, consistent with previous theoretical models. S. aureus also degrades the mechanical integrity of human SC, particularly when the tissue is partially depleted of lipids. These observed mechanical changes are likely the cause of broken or ruptured tissue seen as exudative lesions in AD flares. This work further highlights the necessity of lipids in skin microbial barrier function.

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ARTICLE: Models to Study Skin Lipids in Relation to the Barrier Function: A Modern Update on Models and Methodologies Evaluating Skin Barrier Function

Journal of Drugs in Dermatology ◽

10.36849/jdd.589b ◽

2021 ◽

Vol 20 (4) ◽

pp. s10-s16

Author(s):

Rebecca Barresi ◽

Hawasatu Dumbuya ◽

Xue Liu ◽

I-Chien Liao

Keyword(s):

Barrier Function ◽

Skin Barrier ◽

Skin Barrier Function ◽

Skin Lipids

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Changes in corneocyte element concentrations occur in skin inner stratum corneum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134326 ◽

1990 ◽

Vol 48 (2) ◽

pp. 146-147

Author(s):

R. R. Warner

Keyword(s):

Stratum Corneum ◽

Human Skin ◽

Element Concentration ◽

Skin Barrier ◽

Barrier Properties ◽

Brick Wall ◽

Inorganic Elements ◽

Dry Skin ◽

Skin Biopsies ◽

Intercellular Lipid

Keratinocytes undergo maturation during their transit through the viable layers of skin, and then abruptly transform into flattened, anuclear corneocytes that constitute the cellular component of the skin barrier, the stratum corneum (SC). The SC is generally considered to be homogeneous in its structure and barrier properties, and is often shown schematically as a featureless brick wall, the “bricks” being the corneocytes, the “mortar” being intercellular lipid. Previously we showed the outer SC was not homogeneous in its composition, but contained steep gradients of the physiological inorganic elements Na, K and Cl, likely originating from sweat salts. Here we show the innermost corneocytes in human skin are also heterogeneous in composition, undergoing systematic changes in intracellular element concentration during transit into the interior of the SC.Human skin biopsies were taken from the lower leg of individuals with both “good” and “dry” skin and plunge-frozen in a stirred, cooled isopentane/propane mixture.

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