1
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Nădăban A, Frame CO, El Yachioui D, Gooris GS, Dalgliesh RM, Malfois M, Iacovella CR, Bunge AL, McCabe C, Bouwstra JA. The Sphingosine and Phytosphingosine Ceramide Ratio in Lipid Models Forming the Short Periodicity Phase: An Experimental and Molecular Simulation Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:13794-13809. [PMID: 38917358 PMCID: PMC11238587 DOI: 10.1021/acs.langmuir.4c00554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/27/2024]
Abstract
The lipids located in the outermost layer of the skin, the stratum corneum (SC), play a crucial role in maintaining the skin barrier function. The primary components of the SC lipid matrix are ceramides (CERs), cholesterol (CHOL), and free fatty acids (FFAs). They form two crystalline lamellar phases: the long periodicity phase (LPP) and the short periodicity phase (SPP). In inflammatory skin conditions like atopic dermatitis and psoriasis, there are changes in the SC CER composition, such as an increased concentration of a sphingosine-based CER (CER NS) and a reduced concentration of a phytosphingosine-based CER (CER NP). In the present study, a lipid model was created exclusively forming the SPP, to examine whether alterations in the CER NS:CER NP molar ratio would affect the lipid organization. Experimental data were combined with molecular dynamics simulations of lipid models containing CER NS:CER NP at ratios of 1:2 (mimicking a healthy SC ratio) and 2:1 (observed in inflammatory skin diseases), mixed with CHOL and lignoceric acid as the FFA. The experimental findings show that the acyl chains of CER NS and CER NP and the FFA are in close proximity within the SPP unit cell, indicating that CER NS and CER NP adopt a linear conformation, similarly as observed for the LPP. Both the experiments and simulations indicate that the lamellar organization is the same for the two CER NS:CER NP ratios while the SPP NS:NP 1:2 model had a slightly denser hydrogen bonding network than the SPP NS:NP 2:1 model. The simulations show that this might be attributed to intermolecular hydrogen bonding with the additional hydroxide group on the headgroup of CER NP compared with CER NS.
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Affiliation(s)
- Andreea Nădăban
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
| | - Chloe O Frame
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States of America
| | - Dounia El Yachioui
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
| | - Gerrit S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
| | - Robert M Dalgliesh
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - Marc Malfois
- ALBA Synchrotron, Cerdanyola del Vallès, 08290 Barcelona, Spain
| | - Christopher R Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States of America
| | - Annette L Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, Colorado 80401, United States of America
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235-1604, United States of America
- School of Engineering and Physical Science, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden 2333CC, The Netherlands
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2
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Raschmanová JŠ, Fazekašová S, Martinková M, Fábian M, Pilátová MB, Cvačka J, Kofroňová E, Mezencev R. A 'Chiron' approach to novel phytosphingosine mimetics based on a cascade [3,3]-sigmatropic rearrangement. Carbohydr Res 2024; 541:109158. [PMID: 38796901 DOI: 10.1016/j.carres.2024.109158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/09/2024] [Accepted: 05/20/2024] [Indexed: 05/29/2024]
Abstract
Straightforward access to enantiomerically pure 3,4-diamino-3,4-dideoxyphytosphingosines, as novel analogues of natural d-ribo-phytosphingosine was accomplished, starting from two available chirons: dimethyl l-tartrate and d-isoascorbic acid. A sequential Overman rearrangement followed by late-stage introduction of the alkyl side chain moiety via olefin cross-metathesis is the cornerstone of this approach. The preliminary evaluation study of the synthesised sphingomimetics, based on their ability to inhibit a proliferation of human cancer cells, showed promising cytotoxicity against Jurkat and HeLa cells for (2R,3R,4S)-2,3,4-triaminooctadecan-1-ol trihydrochloride.
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Affiliation(s)
- Jana Špaková Raschmanová
- Institute of Chemical Sciences, Department of Organic Chemistry, P.J. Šafárik University, Moyzesova 11, 040 01, Košice, Slovak Republic
| | - Simona Fazekašová
- Institute of Chemical Sciences, Department of Organic Chemistry, P.J. Šafárik University, Moyzesova 11, 040 01, Košice, Slovak Republic
| | - Miroslava Martinková
- Institute of Chemical Sciences, Department of Organic Chemistry, P.J. Šafárik University, Moyzesova 11, 040 01, Košice, Slovak Republic.
| | - Martin Fábian
- Institute of Chemical Sciences, Department of Organic Chemistry, P.J. Šafárik University, Moyzesova 11, 040 01, Košice, Slovak Republic
| | - Martina Bago Pilátová
- Institute of Pharmacology, Faculty of Medicine, P.J. Šafárik University, SNP 1, 040 66, Košice, Slovak Republic
| | - Josef Cvačka
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo Nám. 2, 16610, Prague, Czech Republic
| | - Edita Kofroňová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo Nám. 2, 16610, Prague, Czech Republic
| | - Roman Mezencev
- Georgia Institute of Technology, College of Science, School of Biology, 310 Ferst Drive, Atlanta, GA, 30332, USA
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3
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Nădăban A, Gooris GS, Beddoes CM, Dalgliesh RM, Malfois M, Demé B, Bouwstra JA. The molecular arrangement of ceramides in the unit cell of the long periodicity phase of stratum corneum models shows a high adaptability to different ceramide head group structures. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184324. [PMID: 38688405 DOI: 10.1016/j.bbamem.2024.184324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 03/06/2024] [Accepted: 04/11/2024] [Indexed: 05/02/2024]
Abstract
The stratum corneum (SC) lipid matrix, composed primarily of ceramides (CERs), cholesterol and free fatty acids (FFA), has an important role for the skin barrier function. The presence of the long periodicity phase (LPP), a unique lamellar phase, is characteristic for the SC. Insight into the lipid molecular arrangement within the LPP unit cell is imperative for understanding the relationship between the lipid subclasses and the skin barrier function. In this study, the impact of the CER head group structure on the lipid arrangement and barrier functionality was investigated using lipid models forming the LPP. The results demonstrate that the positions of CER N-(tetracosanoyl)-sphingosine (CER NS) and CER N-(tetracosanoyl)-phytosphingosine (CER NP), two essentials CER subclasses, are not influenced by the addition of another CER subclass (N-(tetracosanoyl)-dihydrosphingosine (CER NdS), N-(2R-hydroxy-tetracosanoyl)-sphingosine (CER AS) or D-(2R-hydroxy-tetracosanoyl)-phytosphingosine (CER AP)). However, differences are observed in the lipid organization and the hydrogen bonding network of the three different models. A similar localization of CER NP and CER NS is also observed in a more complex lipid model, with the CER subclass composition mimicking that of human SC. These studies show the adaptability and insensitivity of the LPP unit cell structure to changes in the lipid head group structures of the CER subclasses.
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Affiliation(s)
- Andreea Nădăban
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, Leiden 2333CC, the Netherlands
| | - Gerrit S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, Leiden 2333CC, the Netherlands
| | - Charlotte M Beddoes
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, Leiden 2333CC, the Netherlands
| | - Robert M Dalgliesh
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX, United Kingdom
| | - Marc Malfois
- ALBA Synchrotron, Carrer de la Llum 2-6, Cerdanyola del Vallès 08290, Barcelona, Spain
| | - Bruno Demé
- Institut Laue-Langevin, 38000 Grenoble, France
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Einsteinweg 55, Leiden 2333CC, the Netherlands.
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Hernandez-Corbacho M, Canals D. Drug Targeting of Acyltransferases in the Triacylglyceride and 1-O-AcylCeramide Biosynthetic Pathways. Mol Pharmacol 2024; 105:166-178. [PMID: 38164582 DOI: 10.1124/molpharm.123.000763] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 11/09/2023] [Accepted: 11/20/2023] [Indexed: 01/03/2024] Open
Abstract
Acyltransferase enzymes (EC 2.3.) are a large group of enzymes that transfer acyl groups to a variety of substrates. This review focuses on fatty acyltransferases involved in the biosynthetic pathways of glycerolipids and sphingolipids and how these enzymes have been pharmacologically targeted in their biologic context. Glycerolipids and sphingolipids, commonly treated independently in their regulation and biologic functions, are put together to emphasize the parallelism in their metabolism and bioactive roles. Furthermore, a newly considered signaling molecule, 1-O-acylceramide, resulting from the acylation of ceramide by DGAT2 enzyme, is discussed. Finally, the implications of DGAT2 as a putative ceramide acyltransferase (CAT) enzyme, with a putative dual role in TAG and 1-O-acylceramide generation, are explored. SIGNIFICANCE STATEMENT: This manuscript reviews the current status of drug development in lipid acyltransferases. These are current targets in metabolic syndrome and other diseases, including cancer. A novel function for a member in this group of lipids has been recently reported in cancer cells. The responsible enzyme and biological implications of this added member are discussed.
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Affiliation(s)
| | - Daniel Canals
- Department of Medicine, Stony Brook University, Stony Brook, New York
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5
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Mijaljica D, Townley JP, Spada F, Harrison IP. The heterogeneity and complexity of skin surface lipids in human skin health and disease. Prog Lipid Res 2024; 93:101264. [PMID: 37940006 DOI: 10.1016/j.plipres.2023.101264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/27/2023] [Accepted: 11/02/2023] [Indexed: 11/10/2023]
Abstract
The outermost epidermal layer of the skin, the stratum corneum, is not simply a barrier that safeguards skin integrity from external insults and invaders, it is also a delicately integrated interface composed of firm, essentially dead corneocytes and a distinctive lipid matrix. Together, the stratum corneum lipid matrix and sebum lipids derived from sebaceous glands give rise to a remarkably complex but quite unique blend of skin surface lipids that demonstrates tremendous heterogeneity and provides the skin with its indispensable protective coating. The stratum corneum lipid matrix is composed primarily of three major lipid classes: ceramides, non-esterified fatty acids and cholesterol, whereas sebum is a waxy mixture predominantly composed of acylglycerols, wax esters, non-esterified fatty acids, squalene, cholesterol and cholesterol esters. The balance of these skin surface lipids in terms of their relative abundance, composition, molecular organisation and dynamics, and their intricate interactions play a crucial role in the maintenance of healthy skin. For that reason, even minuscule alterations in skin surface lipid properties or overall lipid profile have been implicated in the aetiology of many common skin diseases including atopic dermatitis, psoriasis, xerosis, ichthyosis and acne. Novel lipid-based interventions aimed at correcting the skin surface lipid abnormalities have the potential to repair skin barrier integrity and the symptoms associated with such skin diseases, even though the exact mechanisms of lipid restoration remain elusive.
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Affiliation(s)
- Dalibor Mijaljica
- Department of Scientific Affairs, Ego Pharmaceuticals Pty Ltd, 21-31 Malcolm Road, Braeside, Victoria 3195, Australia.
| | - Joshua P Townley
- Department of Scientific Affairs, Ego Pharmaceuticals Pty Ltd, 21-31 Malcolm Road, Braeside, Victoria 3195, Australia.
| | - Fabrizio Spada
- Department of Scientific Affairs, Ego Pharmaceuticals Pty Ltd, 21-31 Malcolm Road, Braeside, Victoria 3195, Australia.
| | - Ian P Harrison
- Department of Scientific Affairs, Ego Pharmaceuticals Pty Ltd, 21-31 Malcolm Road, Braeside, Victoria 3195, Australia.
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6
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Bouwstra JA, Nădăban A, Bras W, McCabe C, Bunge A, Gooris GS. The skin barrier: An extraordinary interface with an exceptional lipid organization. Prog Lipid Res 2023; 92:101252. [PMID: 37666282 PMCID: PMC10841493 DOI: 10.1016/j.plipres.2023.101252] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/06/2023]
Abstract
The barrier function of the skin is primarily located in the stratum corneum (SC), the outermost layer of the skin. The SC is composed of dead cells with highly organized lipid lamellae in the intercellular space. As the lipid matrix forms the only continuous pathway, the lipids play an important role in the permeation of compounds through the SC. The main lipid classes are ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs). Analysis of the SC lipid matrix is of crucial importance in understanding the skin barrier function, not only in healthy skin, but also in inflammatory skin diseases with an impaired skin barrier. In this review we provide i) a historical overview of the steps undertaken to obtain information on the lipid composition and organization in SC of healthy skin and inflammatory skin diseases, ii) information on the role CERs, CHOL and FFAs play in the lipid phase behavior of very complex lipid model systems and how this knowledge can be used to understand the deviation in lipid phase behavior in inflammatory skin diseases, iii) knowledge on the role of both, CER subclasses and chain length distribution, on lipid organization and lipid membrane permeability in complex and simple model systems with synthetic CERs, CHOL and FFAs, iv) similarity in lipid phase behavior in SC of different species and complex model systems, and vi) future directions in modulating lipid composition that is expected to improve the skin barrier in inflammatory skin diseases.
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Affiliation(s)
- Joke A Bouwstra
- Division of Biotherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.
| | - Andreea Nădăban
- Division of Biotherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Wim Bras
- Chemical Sciences Division, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831, United States of America
| | - Clare McCabe
- School of Engineering & Physical Science, Heriot-Watt University, Edinburgh, Scotland, UK
| | - Annette Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO 80401, United States of America
| | - Gerrit S Gooris
- Division of Biotherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
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7
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Sutter CH, Azim S, Wang A, Bhuju J, Simpson AS, Uberoi A, Grice EA, Sutter TR. Ligand Activation of the Aryl Hydrocarbon Receptor Upregulates Epidermal Uridine Diphosphate Glucose Ceramide Glucosyltransferase and Glucosylceramides. J Invest Dermatol 2023; 143:1964-1972.e4. [PMID: 37004877 PMCID: PMC10529782 DOI: 10.1016/j.jid.2023.03.1662] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 03/08/2023] [Accepted: 03/14/2023] [Indexed: 04/03/2023]
Abstract
Ligand activation of the aryl hydrocarbon receptor (AHR) accelerates keratinocyte differentiation and the formation of the epidermal permeability barrier. Several classes of lipids, including ceramides, are critical to the epidermal permeability barrier. In normal human epidermal keratinocytes, the AHR ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin, increased RNA levels of ceramide metabolism and transport genes: uridine diphosphate glucose ceramide glucosyltransferase (UGCG), ABCA12, GBA1, and SMPD1. Levels of abundant skin ceramides were also increased by 2,3,7,8-tetrachlorodibenzo-p-dioxin. These included the metabolites synthesized by UGCG, glucosylceramides, and acyl glucosylceramides. Chromatin immunoprecipitation-sequence analysis and luciferase reporter assays identified UGCG as a direct AHR target. The AHR antagonist, GNF351, inhibited the 2,3,7,8-tetrachlorodibenzo-p-dioxin-mediated RNA and transcriptional increases. Tapinarof, an AHR ligand approved for the treatment of psoriasis, increased UGCG RNA, protein, and its lipid metabolites hexosylceramides as well as increased the RNA expression of ABCA12, GBA1, and SMPD1. In Ahr-null mice, Ugcg RNA and hexosylceramides were lower than those in the wild type. These results indicate that the AHR regulates the expression of UGCG, a ceramide-metabolizing enzyme required for ceramide trafficking, keratinocyte differentiation, and epidermal permeability barrier formation.
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Affiliation(s)
- Carrie Hayes Sutter
- Department of Biological Sciences, The University of Memphis, Memphis, Tennessee, USA
| | - Shafquat Azim
- Department of Biological Sciences, The University of Memphis, Memphis, Tennessee, USA; Department of Surgery, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Anyou Wang
- Department of Biological Sciences, The University of Memphis, Memphis, Tennessee, USA
| | - Jyoti Bhuju
- Department of Biological Sciences, The University of Memphis, Memphis, Tennessee, USA; Sanegene Bio USA, Cambridge, Massachusetts, USA
| | - Amelia S Simpson
- Department of Biological Sciences, The University of Memphis, Memphis, Tennessee, USA
| | - Aayushi Uberoi
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Elizabeth A Grice
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Thomas R Sutter
- Department of Biological Sciences, The University of Memphis, Memphis, Tennessee, USA; Department of Chemistry, The University of Memphis, Memphis, Tennessee, USA.
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8
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Du W, He L, Wang Z, Dong Y, He X, Hu J, Zhang M. Serum lipidomics-based study of electroacupuncture for skin wound repair in rats. J Cell Mol Med 2023; 27:3127-3146. [PMID: 37517065 PMCID: PMC10568671 DOI: 10.1111/jcmm.17891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/16/2023] [Accepted: 07/22/2023] [Indexed: 08/01/2023] Open
Abstract
Lipid metabolism plays an important role in the repair of skin wounds. Studies have shown that acupuncture is very effective in skin wound repair. However, there is little knowledge about the mechanism of electroacupuncture. Thirty-six SD rats were divided into three groups: sham-operated group, model group and electroacupuncture group, with six rats in each group. After the intervention, orbital venous blood was collected for lipid metabolomics analysis, wound perfusion was detected and finally the effect of electroacupuncture on skin wound repair was comprehensively evaluated by combining wound healing rate and histology. Lipid metabolomics analysis revealed 11 differential metabolites in the model versus sham-operated group. There were 115 differential metabolites in the model versus electro-acupuncture group. 117 differential metabolites in the electro-acupuncture versus sham-operated group. There were two differential metabolites common to all three groups. Mainly cholesteryl esters and sphingolipids were elevated after electroacupuncture and triglycerides were largely decreased after electroacupuncture. The electroacupuncture group recovered faster than the model group in terms of blood perfusion and wound healing (p < 0.05). Electroacupuncture may promote rat skin wound repair by improving lipid metabolism and improving local perfusion.
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Affiliation(s)
- Weibin Du
- Research Institute of OrthopaedicsThe Affiliated Jiangnan Hospital of Zhejiang Chinese Medical UniversityZhejiangChina
- Hangzhou Xiaoshan Hospital of Traditional Chinese MedicineZhejiangChina
| | - Lihong He
- Research Institute of OrthopaedicsThe Affiliated Jiangnan Hospital of Zhejiang Chinese Medical UniversityZhejiangChina
- Hangzhou Xiaoshan Hospital of Traditional Chinese MedicineZhejiangChina
| | - Zhenwei Wang
- Research Institute of OrthopaedicsThe Affiliated Jiangnan Hospital of Zhejiang Chinese Medical UniversityZhejiangChina
- Hangzhou Xiaoshan Hospital of Traditional Chinese MedicineZhejiangChina
| | - Yi Dong
- Shaoxing TCM Hospital Affiliated to Zhejiang Chinese Medical UniversityZhejiangChina
| | - Xiaofen He
- Key Laboratory of Acupuncture and Neurology of Zhejiang Province, Department of Neurobiology and Acupuncture ResearchZhejiang Chinese Medical University, The Third Clinical Medical CollegeZhejiangChina
| | - Jintao Hu
- Orthopaedics and Traumatology DepartmentHangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical UniversityZhejiangChina
| | - Min Zhang
- Research Institute of OrthopaedicsThe Affiliated Jiangnan Hospital of Zhejiang Chinese Medical UniversityZhejiangChina
- Hangzhou Xiaoshan Hospital of Traditional Chinese MedicineZhejiangChina
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9
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Nădăban A, Rousel J, El Yachioui D, Gooris GS, Beddoes CM, Dalgliesh RM, Malfois M, Rissmann R, Bouwstra JA. Effect of sphingosine and phytosphingosine ceramide ratio on lipid arrangement and barrier function in skin lipid models. J Lipid Res 2023; 64:100400. [PMID: 37301511 PMCID: PMC10457584 DOI: 10.1016/j.jlr.2023.100400] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/15/2023] [Accepted: 06/06/2023] [Indexed: 06/12/2023] Open
Abstract
The lipids in the uppermost layer of the skin, the stratum corneum (SC), play an important role in the skin barrier function. The three main subclasses in the SC lipid matrix are ceramides (CER), cholesterol, and free fatty acids. In inflammatory skin diseases, such as atopic dermatitis and psoriasis, the SC lipid composition is modulated compared to the composition in healthy SC. One of the main alterations is the molar ratio between the concentration of CER N-(tetracosanoyl)-sphingosine (CER NS) and CER N-(tetracosanoyl)-phytosphingosine (CER NP), which correlated with an impaired skin barrier function. In the present study, we investigated the impact of varying the CER NS:CER NP ratios on the lipid organization, lipid arrangement, and barrier functionality in SC lipid model systems. The results indicate that a higher CER NS:CER NP ratio as observed in diseased skin did not alter the lipid organization or lipid arrangement in the long periodicity phase encountered in SC. The trans-epidermal water loss, an indication of the barrier functionality, was significantly higher for the CER NS:CER NP 2:1 model (mimicking the ratio in inflammatory skin diseases) compared to the CER NS:CER NP 1:2 ratio (in healthy skin). These findings provide a more detailed insight into the lipid organization in both healthy and diseased skin and suggest that in vivo the molar ratio between CER NS:CER NP contributes to barrier impairment as well but might not be the main factor.
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Affiliation(s)
- Andreea Nădăban
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Jannik Rousel
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands; Centre for Human Drug Research, Leiden, The Netherlands
| | - Dounia El Yachioui
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Gerrit S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Charlotte M Beddoes
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Robert M Dalgliesh
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, United Kingdom
| | | | - Robert Rissmann
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands; Centre for Human Drug Research, Leiden, The Netherlands; Leiden University Medical Center, Leiden, The Netherlands
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.
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10
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Miyauchi M, Ishikawa S, Kurachi T, Sakamoto K, Sakai H. Oral Absorption across Organotypic Culture Models of the Human Buccal Epithelium after E-cigarette Aerosol Exposure. ACS OMEGA 2022; 7:45574-45581. [PMID: 36530294 PMCID: PMC9753183 DOI: 10.1021/acsomega.2c06304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 11/21/2022] [Indexed: 06/17/2023]
Abstract
Inhaled aerosols are absorbed across the oral cavity, respiratory tract, and gastrointestinal tract. The absorption across the oral cavity, which is one of the exposure routes, plays an important role in understanding pharmacokinetics and physiological effects. After aerosol exposure from e-cigarettes, tissue viability studies, morphological observation, and chemical analyses at the inner and outer buccal tissues were performed using organotypic 3D in vitro culture models of the buccal epithelium to better understand the deposition and absorption on the inner and outer buccal tissues. The aerosol exposures did not affect the tissue viability and had no change to the tissue morphology and structure. The deposition ratio at the buccal tissue surface is relatively low. This shows that majority of aerosol transfers to the airway tissues. The distribution from the inner tissue to the outer tissue has selectivity among various compounds, depending on the affinity with the liquid crystal structure of phospholipids and glucosylceramide. Although nicotine absorption in the aqueous solution was well known to increase as the unprotonated state of nicotine increased, the nicotine absorption after the aerosol exposure is irrelevant to the protonated-unprotonated state. Furthermore, the results showed that half of nicotine that adhered to the oral cavity transferred to the inner tissue via the oral epithelium and the other half transferred to the gastrointestinal tract accompanying multiple executions of swallowing, while majority of the water-soluble compounds with the hydroxyl group such as propylene glycol and benzoic acid that adhered to the oral cavity were eluted with the saliva and transferred to the gastrointestinal tract by swallowing.
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Affiliation(s)
- Masato Miyauchi
- Tobacco
Science Research Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba, Yokohama, Kanagawa 227-8512, Japan
| | - Shinkichi Ishikawa
- Scientific
Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba, Yokohama, Kanagawa 227-8512, Japan
| | - Takeshi Kurachi
- Scientific
Product Assessment Center, R&D Group, Japan Tobacco Inc., 6-2 Umegaoka, Aoba, Yokohama, Kanagawa 227-8512, Japan
| | - Kazutami Sakamoto
- Department
of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Hideki Sakai
- Department
of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
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11
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Experimental Study of the Reduction in Ceramide Content in Fingernails Due to Nail Polish Remover Use. COSMETICS 2022. [DOI: 10.3390/cosmetics9060125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The amount and distribution of ceramide, an intercellular lipid, in the fingernails of three Japanese women in their twenties were examined by high-performance liquid chromatography and antibody staining. In addition, the structural changes of fingernail cross sections were examined after fingernails were immersed in an acetone-based nail polish remover solution. The acetone-treated fingernails had a lower water content and higher water evaporation than the inner forearm skin and healthy fingernails, suggesting that they had compromised moisturizing and barrier functions and were more susceptible to roughness and damage. These results also suggest that, compared to healthy fingernails, rough fingernails are more prone to breakage and damage. Furthermore, it was found that the amount of ceramide decreased when fingernails were immersed in nail polish remover solution. The distribution showed ceramide to be present in the ventral and dorsal regions of the free edge of the fingernail plate. After immersion in nail polish remover, the three-layered structure of the free edge of the plate was intact, but the dorsal distal edge of the plate peeled off. Gaps were observed inside the free edge of the plate, which should have been layered. These results show that the frequent use of nail polish remover may worsen condition of fingernails.
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12
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Badhe Y, Schmitt T, Gupta R, Rai B, Neubert RH. Investigating the nanostructure of a CER[NP]/CER[AP]-based stratum corneum lipid matrix model: A combined neutron diffraction & molecular dynamics simulations approach. BIOCHIMICA ET BIOPHYSICA ACTA (BBA) - BIOMEMBRANES 2022; 1864:184007. [PMID: 35863424 DOI: 10.1016/j.bbamem.2022.184007] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 06/29/2022] [Accepted: 07/12/2022] [Indexed: 10/17/2022]
Abstract
The human skin provides a physiochemical and biological protective barrier due to the unique structure of its outermost layer known as the Stratum corneum. This layer consists of corneocytes and a multi-lamellar lipid matrix forming a composite, which is a major determining factor for the barrier function of the Stratum corneum. A substantiated understanding of this barrier is necessary, as controlled breaching or modulation of the same is also essential for various health and personal care applications such as topical drug delivery and cosmetics to a name few. In this study, we discuss the state-of-the-art of neutron diffraction techniques, using specifically deuterated lipids, combined with the information obtained from molecular models using molecular dynamics simulations, to understand the structure and barrier function of the Stratum corneum lipid matrix. As an example, the effect of ceramide concentration on a lipid lamella system consisting of CER[NP]/CER[AP]/Cholesterol/free fatty acid (deprotonated) is studied. This study demonstrates the usefulness of the combined approach of neutron diffraction and molecular dynamics simulations for effective analysis of the model systems created for the Stratum corneum lipid matrix. The optimization of force fields by comparison with experimental data is furthermore an important step in the direction of providing a predictive quality.
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13
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Nădăban A, Gooris GS, Beddoes CM, Dalgliesh RM, Bouwstra JA. Phytosphingosine ceramide mainly localizes in the central layer of the unique lamellar phase of skin lipid model systems. J Lipid Res 2022; 63:100258. [PMID: 35931203 PMCID: PMC9421324 DOI: 10.1016/j.jlr.2022.100258] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 11/17/2022] Open
Abstract
Understanding the lipid arrangement within the skin's outermost layer, the stratum corneum (SC), is important for advancing knowledge on the skin barrier function. The SC lipid matrix consists of ceramides (CERs), cholesterol, and free fatty acids, which form unique crystalline lamellar phases, referred to as the long periodicity phase (LPP) and short periodicity phases. As the SC lipid composition is complex, lipid model systems that mimic the properties of native SC are used to study the SC lipid organization and molecular arrangement. In previous studies, such lipid models were used to determine the molecular organization in the trilayer structure of the LPP unit cell. The aim of this study was to examine the location of CER N-(tetracosanoyl)-phytosphingosine (CER NP) in the unit cell of this lamellar phase and compare its position with CER N-(tetracosanoyl)-sphingosine (CER NS). We selected CER NP as it is the most prevalent CER subclass in the human SC, and its location in the LPP is not known. Our neutron diffraction results demonstrate that the acyl chain of CER NP was positioned in the central part of the trilayer structure, with a fraction also present in the outer layers, the same location as determined for the acyl chain of CER NS. In addition, our Fourier transformed infrared spectroscopy results are in agreement with this molecular arrangement, suggesting a linear arrangement for the CER NS and CER NP. These findings provide more detailed insight into the lipid organization in the SC lipid matrix.
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Affiliation(s)
- Andreea Nădăban
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Gerrit S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Charlotte M Beddoes
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - Robert M Dalgliesh
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, United Kingdom
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.
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14
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Shamaprasad P, Frame CO, Moore TC, Yang A, Iacovella CR, Bouwstra JA, Bunge AL, McCabe C. Using molecular simulation to understand the skin barrier. Prog Lipid Res 2022; 88:101184. [PMID: 35988796 PMCID: PMC10116345 DOI: 10.1016/j.plipres.2022.101184] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/15/2022]
Abstract
Skin's effectiveness as a barrier to permeation of water and other chemicals rests almost entirely in the outermost layer of the epidermis, the stratum corneum (SC), which consists of layers of corneocytes surrounded by highly organized lipid lamellae. As the only continuous path through the SC, transdermal permeation necessarily involves diffusion through these lipid layers. The role of the SC as a protective barrier is supported by its exceptional lipid composition consisting of ceramides (CERs), cholesterol (CHOL), and free fatty acids (FFAs) and the complete absence of phospholipids, which are present in most biological membranes. Molecular simulation, which provides molecular level detail of lipid configurations that can be connected with barrier function, has become a popular tool for studying SC lipid systems. We review this ever-increasing body of literature with the goals of (1) enabling the experimental skin community to understand, interpret and use the information generated from the simulations, (2) providing simulation experts with a solid background in the chemistry of SC lipids including the composition, structure and organization, and barrier function, and (3) presenting a state of the art picture of the field of SC lipid simulations, highlighting the difficulties and best practices for studying these systems, to encourage the generation of robust reproducible studies in the future. This review describes molecular simulation methodology and then critically examines results derived from simulations using atomistic and then coarse-grained models.
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Affiliation(s)
- Parashara Shamaprasad
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Chloe O Frame
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Timothy C Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Alexander Yang
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Christopher R Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America
| | - Joke A Bouwstra
- Division of BioTherapeutics, LACDR, Leiden University, 2333 CC Leiden, the Netherlands
| | - Annette L Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO 80401, United States of America
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235-1604, United States of America; Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN 37235-1604, United States of America; School of Engineering and Physical Science, Heriot-Watt University, Edinburgh, United Kingdom.
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15
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Goh CF, Hadgraft J, Lane ME. Thermal analysis of mammalian stratum corneum using differential scanning calorimetry for advancing skin research and drug delivery. Int J Pharm 2022; 614:121447. [PMID: 34998922 DOI: 10.1016/j.ijpharm.2021.121447] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 11/15/2022]
Abstract
For effective topical and transdermal drug delivery, it is necessary for most actives to penetrate and permeate through the stratum corneum (SC). Extensive investigation of the thermal behaviour of mammalian SC has been performed to understand the barrier function of the skin. However, little attention has been paid to the related experimental variables in thermal analysis of the SC using differential scanning calorimetry that may influence the results obtained from such studies. In this review, we provide a comprehensive overview of the thermal transitions of the SC of both porcine and human skin. More importantly, the selection and impact of the experimental and instrumental parameters used in thermal analysis of the SC are critically evaluated. New opportunities for the use of thermal analysis of mammalian SC in advancing skin research, particularly for elucidation of the actions of excipients employed in topical and transdermal formulations on the skin are also highlighted.
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Affiliation(s)
- Choon Fu Goh
- Discipline of Pharmaceutical Technology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
| | - Jonathan Hadgraft
- Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Majella E Lane
- Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom.
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16
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Effects of age, sex, and breed on the composition of free extractable ceramides in the stratum corneum of healthy dogs. Vet Res Commun 2021; 46:121-126. [PMID: 34687003 DOI: 10.1007/s11259-021-09835-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/15/2021] [Indexed: 10/20/2022]
Abstract
Ceramide (CER), an important component of the extracellular lamellar lipids in the stratum corneum (SC), plays a critical role in maintaining the cutaneous barrier function. This study aimed to determine whether the quantity of free extractable SC CERs in dogs was affected by the age, sex, or breed. Fifty-eight dogs from the breeds Shiba Inu, beagle, miniature dachshund, shih tzu, and golden retriever, without any history of skin problems, were enrolled in this study. Lipid extracts from the SC were subjected to high-performance thin-layer chromatography to quantify the free extractable CERs. There were weak negative correlations between the age and the amount of free extractable CERs, CER [NP] (non-hydroxy fatty acids linked to phytosphingosines), CER [AS/NH] (α-hydroxy fatty acids linked to sphingosines/non-hydroxy fatty acids linked to 6-hydroxysphingosines), and CER [AP] (α-hydroxy fatty acids and phytosphingosines). There were no significant sex- or breed-related differences in the amounts of free extractable SC CERs in the dogs. These findings imply that aging causes a decline in the amount of free extractable SC CERs in dogs, similar to that observed in humans. The sex or breed of the dogs investigated in this study did not influence the amount of free extractable SC CERs.
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17
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Fujii M. The Pathogenic and Therapeutic Implications of Ceramide Abnormalities in Atopic Dermatitis. Cells 2021; 10:2386. [PMID: 34572035 PMCID: PMC8468445 DOI: 10.3390/cells10092386] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/05/2021] [Accepted: 09/07/2021] [Indexed: 11/16/2022] Open
Abstract
Ceramides play an essential role in forming a permeability barrier in the skin. Atopic dermatitis (AD) is a common chronic skin disease associated with skin barrier dysfunction and immunological abnormalities. In patients with AD, the amount and composition of ceramides in the stratum corneum are altered. This suggests that ceramide abnormalities are involved in the pathogenesis of AD. The mechanism underlying lipid abnormalities in AD has not yet been fully elucidated, but the involvement of Th2 and Th1 cytokines is implicated. Ceramide-dominant emollients have beneficial effects on skin barrier function; thus, they have been approved as an adjunctive barrier repair agent for AD. This review summarizes the current understanding of the mechanisms of ceramide abnormalities in AD. Furthermore, the potential therapeutic approaches for correcting ceramide abnormalities in AD are discussed.
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Affiliation(s)
- Masanori Fujii
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan
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18
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Bouwstra JA, Helder RW, El Ghalbzouri A. Human skin equivalents: Impaired barrier function in relation to the lipid and protein properties of the stratum corneum. Adv Drug Deliv Rev 2021; 175:113802. [PMID: 34015420 DOI: 10.1016/j.addr.2021.05.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/12/2021] [Accepted: 05/15/2021] [Indexed: 12/15/2022]
Abstract
To advance drug development representative reliable skin models are indispensable. Animal skin as test model for human skin delivery is restricted as their properties greatly differ from human skin. In vitro 3D-human skin equivalents (HSEs) are valuable tools as they recapitulate important aspects of the human skin. However, HSEs still lack the full barrier functionality as observed in native human skin, resulting in suboptimal screening outcome. In this review we provide an overview of established in-house and commercially available HSEs and discuss in more detail to what extent their skin barrier biology is mimicked in vitro focusing on the lipid properties and cornified envelope. Further, we will illustrate how underlying factors, such as culture medium improvements and environmental factors affect the barrier lipids. Lastly, potential improvements in skin barrier function will be proposed aiming at a new generation of HSEs that may replace animal skin delivery studies fully.
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19
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Kováčik A, Pullmannová P, Opálka L, Šilarová M, Maixner J, Vávrová K. Effects of ( R)- and ( S)-α-Hydroxylation of Acyl Chains in Sphingosine, Dihydrosphingosine, and Phytosphingosine Ceramides on Phase Behavior and Permeability of Skin Lipid Models. Int J Mol Sci 2021; 22:ijms22147468. [PMID: 34299088 PMCID: PMC8303283 DOI: 10.3390/ijms22147468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/08/2021] [Accepted: 07/09/2021] [Indexed: 11/16/2022] Open
Abstract
Ceramides (Cers) with α-hydroxylated acyl chains comprise about a third of all extractable skin Cers and are required for permeability barrier homeostasis. We have probed here the effects of Cer hydroxylation on their behavior in lipid models comprising the major SC lipids, Cer/free fatty acids (C 16-C 24)/cholesterol, and a minor component, cholesteryl sulfate. Namely, Cers with (R)-α-hydroxy lignoceroyl chains attached to sphingosine (Cer AS), dihydrosphingosine (Cer AdS), and phytosphingosine (Cer AP) were compared to their unnatural (S)-diastereomers and to Cers with non-hydroxylated lignoceroyl chains attached to sphingosine (Cer NS), dihydrosphingosine (Cer NdS), and phytosphingosine (Cer NP). By comparing several biophysical parameters (lamellar organization by X-ray diffraction, chain order, lateral packing, phase transitions, and lipid mixing by infrared spectroscopy using deuterated lipids) and the permeabilities of these models (water loss and two permeability markers), we conclude that there is no general or common consequence of Cer α-hydroxylation. Instead, we found a rich mix of effects, highly dependent on the sphingoid base chain, configuration at the α-carbon, and permeability marker used. We found that the model membranes with unnatural Cer (S)-AS have fewer orthorhombically packed lipid chains than those based on the (R)-diastereomer. In addition, physiological (R)-configuration decreases the permeability of membranes, with Cer (R)-AdS to theophylline, and increases the lipid chain order in model systems with natural Cer (R)-AP. Thus, each Cer subclass makes a distinct contribution to the structural organization and function of the skin lipid barrier.
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Affiliation(s)
- Andrej Kováčik
- Skin Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic; (P.P.); (L.O.); (M.Š.); (K.V.)
- Correspondence: ; Tel.: +420-495-067-340
| | - Petra Pullmannová
- Skin Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic; (P.P.); (L.O.); (M.Š.); (K.V.)
| | - Lukáš Opálka
- Skin Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic; (P.P.); (L.O.); (M.Š.); (K.V.)
| | - Michaela Šilarová
- Skin Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic; (P.P.); (L.O.); (M.Š.); (K.V.)
| | - Jaroslav Maixner
- Faculty of Chemical Technology, University of Chemistry and Technology in Prague, Technická 5, 166 28 Prague, Czech Republic;
| | - Kateřina Vávrová
- Skin Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic; (P.P.); (L.O.); (M.Š.); (K.V.)
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20
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Wertz PW. Roles of Lipids in the Permeability Barriers of Skin and Oral Mucosa. Int J Mol Sci 2021; 22:ijms22105229. [PMID: 34063352 PMCID: PMC8155912 DOI: 10.3390/ijms22105229] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/05/2021] [Accepted: 05/10/2021] [Indexed: 02/06/2023] Open
Abstract
PubMed searches reveal much literature regarding lipids in barrier function of skin and less literature on lipids in barrier function of the oral mucosa. In terrestrial mammals, birds, and reptiles, the skin’s permeability barrier is provided by ceramides, fatty acids, and cholesterol in the outermost layers of the epidermis, the stratum corneum. This layer consists of about 10–20 layers of cornified cells embedded in a lipid matrix. It effectively prevents loss of water and electrolytes from the underlying tissue, and it limits the penetration of potentially harmful substances from the environment. In the oral cavity, the regions of the gingiva and hard palate are covered by keratinized epithelia that much resemble the epidermis. The oral stratum corneum contains a lipid mixture similar to that in the epidermal stratum corneum but in lower amounts and is accordingly more permeable. The superficial regions of the nonkeratinized oral epithelia also provide a permeability barrier. These epithelial regions do contain ceramides, cholesterol, and free fatty acids, which may underlie barrier function. The oral epithelial permeability barriers primarily protect the underlying tissue by preventing the penetration of potentially toxic substances, including microbial products. Transdermal drug delivery, buccal absorption, and lipid-related disease are discussed.
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21
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Mojumdar EH, Sparr E. The effect of pH and salt on the molecular structure and dynamics of the skin. Colloids Surf B Biointerfaces 2021; 198:111476. [DOI: 10.1016/j.colsurfb.2020.111476] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/08/2020] [Accepted: 11/09/2020] [Indexed: 01/17/2023]
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Strati F, Neubert RHH, Opálka L, Kerth A, Brezesinski G. Non-ionic surfactants as innovative skin penetration enhancers: insight in the mechanism of interaction with simple 2D stratum corneum model system. Eur J Pharm Sci 2021; 157:105620. [PMID: 33122012 DOI: 10.1016/j.ejps.2020.105620] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 11/16/2022]
Abstract
Transdermal drug delivery is a passive diffusion process of an active compound through the skin which is affected by drug solubility in the multilamellar lipidic matrix of the stratum corneum (SC). Widely used non-ionic surfactants (NIS) can be added into transdermal formulations to enhance the penetration of drugs by influencing the packing of the stratum corneum lipidic matrix. Objective of our study was to analyse the interaction between selected NIS and a simple SC lipidic matrix model system using a variety of surface-sensitive techniques based on the application of Langmuir monolayers. In this work, the well-known surfactant Polysorbate 80 was compared with a modern surfactant Sucrose monolaurate. Infrared reflection-absorption spectroscopy (IRRAS) and epifluorescence microscopy provide information about the effects of those surfactants on the SC model system. Monolayer isotherms of the SC model mixture indicate a very stiff and well-packed layer, however, packing defects are evidenced in epifluorescence studies. The injection of the two NIS underneath the SC monolayers proved their potential to penetrate into the SC model at the air-water interface having a maximum insertion pressure (MIP) above the assumed lateral pressure of biological membranes. The NIS adsorbed preferentially into packing defects seen in epifluorescence microscopy studies with Sucrose monolaurate being more active than Polysorbate 80 in disordering the SC monolayer.
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Affiliation(s)
- Fabio Strati
- Institute of Applied Dermatopharmacy at Martin Luther University Halle-Wittenberg, Weinbergweg 23, D-06120 Halle (Saale), Germany.
| | - Reinhard H H Neubert
- Institute of Applied Dermatopharmacy at Martin Luther University Halle-Wittenberg, Weinbergweg 23, D-06120 Halle (Saale), Germany
| | - Lukáš Opálka
- Charles University, Faculty of Pharmacy in Hradec Kralove, Akademika Heyrovskeho 1203, Hradec Kralove, 500 05, Czech Republic
| | - Andreas Kerth
- Institute of Chemistry - Physical Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, D-06120 Halle (Saale), Germany
| | - Gerald Brezesinski
- Institute of Applied Dermatopharmacy at Martin Luther University Halle-Wittenberg, Weinbergweg 23, D-06120 Halle (Saale), Germany
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The Effect of Prickly Pear, Pumpkin, and Linseed Oils on Biological Mediators of Acute Inflammation and Oxidative Stress Markers. BIOMED RESEARCH INTERNATIONAL 2020; 2020:5643465. [PMID: 32802857 PMCID: PMC7421017 DOI: 10.1155/2020/5643465] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 07/01/2020] [Accepted: 07/14/2020] [Indexed: 01/24/2023]
Abstract
Medicinal plants have been used as a source of effective and safe alternative therapeutic agents for various ailments including inflammation. In fact, the aim of this study is to assess the topical anti-inflammatory and antioxidative potential effects of Cucurbita pepo (pumpkin), Linum usitatissimum (linseed), and Opuntia ficus indica (prickly pear) oils on acute inflammation using carrageenan-induced paw edema model. The study was conducted on 36 rats splitted in 6 groups: a normal control group and 5 carrageenan-treated groups (1%), each treated with either a normal saline, the reference drug (“Inflocine®” 2 mg/paw), pumpkin, linseed, or prickly pear oils (25 μl/paw). The response to these treatments was mainly assessed by the measuring of edema paw size, hematological and biochemical analysis, oxidative stress testing, and histological study. All the studied seed oils especially prickly pear oil proved to be efficient in treating acute inflammation. The oil-treated groups revealed a significant (p < 0.05) decrease in the clinical signs of inflammation, hematological parameters (white blood cells and platelets), concentrations of CRP and fibrinogen, and congestion compared to the normal saline-treated group. The results also showed that the tested oils, endowed with a radical scavenging ability, could significantly increase the activities of SOD, CAT, and GPx in carrageenan-treated skin by reducing the lipid peroxidation and protein oxidation (TBARS, AOPP). The anti-inflammatory effect of the tested oils was closely related to both their antioxidant properties as well as their bioactive compounds (polyunsaturated fatty acids, vitamin E, and phytosterols). For the first time, the findings of the current study highlight the “in vivo” anti-inflammatory property of pumpkin, linseed, and prickly pear oils on carrageenan-induced acute inflammation by regulating inflammatory mediators and oxidative stress markers.
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24
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Dijkhoff IM, Drasler B, Karakocak BB, Petri-Fink A, Valacchi G, Eeman M, Rothen-Rutishauser B. Impact of airborne particulate matter on skin: a systematic review from epidemiology to in vitro studies. Part Fibre Toxicol 2020; 17:35. [PMID: 32711561 PMCID: PMC7382801 DOI: 10.1186/s12989-020-00366-y] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 07/14/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Air pollution is killing close to 5 million people a year, and harming billions more. Air pollution levels remain extremely high in many parts of the world, and air pollution-associated premature deaths have been reported for urbanized areas, particularly linked to the presence of airborne nano-sized and ultrafine particles. MAIN TEXT To date, most of the research studies did focus on the adverse effects of air pollution on the human cardiovascular and respiratory systems. Although the skin is in direct contact with air pollutants, their damaging effects on the skin are still under investigation. Epidemiological data suggested a correlation between exposure to air pollutants and aggravation of symptoms of chronic immunological skin diseases. In this study, a systematic literature review was conducted to understand the current knowledge on the effects of airborne particulate matter on human skin. It aims at providing a deeper understanding of the interactions between air pollutants and skin to further assess their potential risks for human health. CONCLUSION Particulate matter was shown to induce a skin barrier dysfunction and provoke the formation of reactive oxygen species through direct and indirect mechanisms, leading to oxidative stress and induced activation of the inflammatory cascade in human skin. Moreover, a positive correlation was reported between extrinsic aging and atopic eczema relative risk with increasing particulate matter exposure.
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Affiliation(s)
- Irini M Dijkhoff
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700, Fribourg, Switzerland
| | - Barbara Drasler
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700, Fribourg, Switzerland
| | - Bedia Begum Karakocak
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700, Fribourg, Switzerland
| | - Alke Petri-Fink
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700, Fribourg, Switzerland
| | - Giuseppe Valacchi
- Department of Biomedical and Specialist Surgical Sciences, University of Ferrara, Ferrara, Italy
- Department of Animal Sciences, PHHI NCRC, North Carolina State University, Kannapolis, NC, USA
| | | | - Barbara Rothen-Rutishauser
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700, Fribourg, Switzerland.
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Martins Cardoso R, Absalah S, Van Eck M, Bouwstra JA. Barrier lipid composition and response to plasma lipids: A direct comparison of mouse dorsal back and ear skin. Exp Dermatol 2020; 29:548-555. [PMID: 32350936 PMCID: PMC7383511 DOI: 10.1111/exd.14106] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/27/2020] [Accepted: 04/20/2020] [Indexed: 12/19/2022]
Abstract
The skin of the ear and the back are frequently selected sites in skin research using mouse models. However, distinct responses to treatment have been described between these two sites in several studies. Despite the crucial role of the stratum corneum (SC) in the skin barrier function of both dorsal back and ear skin, it remains unclear whether differences in lipid composition might underlie altered responses. Here, we compared the skin morphology and the barrier lipid composition of the ear with the back skin of wild-type mice. The ear contained more corneocyte layers in the SC and its barrier lipid composition was enriched with sphingosine ceramide subclasses, especially the short ones with a total chain length of 33-34 carbons. The free fatty acid (FFA) profile in the ear skin shifted towards shorter chains, significantly reducing the mean chain length to 23.3 vs 24.7 carbons in the back skin. In line, FFA species in the ear displayed a twofold increase in unsaturation index (P < .001). Gene expression in the ear skin revealed low expression of genes involved in lipid synthesis and uptake, indicating a reduced metabolic activity. Finally, the effects of hypercholesterolaemia on SC FFA composition was compared in ear and back skin of apolipoprotein E knockout (APOE-/- ) mice. Interestingly, the FFA profile in APOE-/- ear skin was minimally affected, while the FFA composition in the back skin was markedly changed in response to hypercholesterolaemia. In conclusion, ear and back skin have distinct barrier lipids and respond differently to elevated plasma cholesterol.
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Affiliation(s)
- Renata Martins Cardoso
- Division BioTherapeuticsLeiden Academic Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Samira Absalah
- Division BioTherapeuticsLeiden Academic Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Miranda Van Eck
- Division BioTherapeuticsLeiden Academic Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Joke A. Bouwstra
- Division BioTherapeuticsLeiden Academic Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
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Martins Cardoso R, Creemers E, Absalah S, Hoekstra M, Gooris GS, Bouwstra JA, Van Eck M. Hyperalphalipoproteinemic scavenger receptor BI knockout mice exhibit a disrupted epidermal lipid barrier. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158592. [PMID: 31863970 DOI: 10.1016/j.bbalip.2019.158592] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/05/2019] [Accepted: 12/16/2019] [Indexed: 01/28/2023]
Abstract
Scavenger receptor class B type I (SR-BI) mediates the selective uptake of cholesteryl esters (CE) from high-density lipoproteins (HDL). An impaired SR-BI function leads to hyperalphalipoproteinemia with elevated levels of cholesterol transported in the HDL fraction. Accumulation of cholesterol in apolipoprotein B (apoB)-containing lipoproteins has been shown to alter skin lipid composition and barrier function in mice. To investigate whether these hypercholesterolemic effects on the skin also occur in hyperalphalipoproteinemia, we compared skins of wild-type and SR-BI knockout (SR-BI-/-) mice. SR-BI deficiency did not affect the epidermal cholesterol content and induced only minor changes in the ceramide subclasses. The epidermal free fatty acid (FFA) pool was, however, enriched in short and unsaturated chains. Plasma CE levels strongly correlated with epidermal FFA C18:1 content. The increase in epidermal FFA coincided with downregulation of cholesterol and FFA synthesis genes, suggesting a compensatory response to increased flux of plasma cholesterol and FFAs into the skin. Importantly, the SR-BI-/- epidermal lipid barrier showed increased permeability to ethyl-paraminobenzoic acid, indicating an impairment of the barrier function. In conclusion, increased HDL-cholesterol levels in SR-BI-/- mice can alter the epidermal lipid composition and lipid barrier function similarly as observed in hypercholesterolemia due to elevated levels of apoB-containing lipoproteins.
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Affiliation(s)
- Renata Martins Cardoso
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands.
| | - Eline Creemers
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands
| | - Samira Absalah
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands.
| | - Menno Hoekstra
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands.
| | - Gert S Gooris
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands.
| | - Joke A Bouwstra
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands.
| | - Miranda Van Eck
- Division BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, Leiden, Zuid-Holland, the Netherlands.
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Boiten W, Helder R, van Smeden J, Bouwstra J. Selectivity in cornified envelop binding of ceramides in human skin and the role of LXR inactivation on ceramide binding. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1206-1213. [PMID: 31112754 DOI: 10.1016/j.bbalip.2019.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 04/23/2019] [Accepted: 05/10/2019] [Indexed: 12/11/2022]
Abstract
The cornified lipid envelope (CLE) is a lipid monolayer covalently bound to the outside of corneocytes and is part of the stratum corneum (SC). The CLE is suggested to act as a scaffold for the unbound SC lipids. By profiling the bound CLE ceramides, a new subclass was discovered and identified as an omega-hydroxylated dihydrosphingosine (OdS) ceramide. Bound glucosylceramides were observed in superficial SC layers of healthy human skin. To investigate the relation between bound and unbound SC ceramides, the composition of both fractions was analyzed and compared. Selectivity in ceramide binding towards unsaturated ceramides and ceramides with a shorter chain length was observed. The selectivity in ceramide species bound to the cornified envelope is thought to have a physiological function in corneocyte flexibility. Next, it was examined if skin models exhibit an altered bound ceramide composition and if the composition was dependent on liver X-receptor (LXR) activation. The effects of an LXR agonist and antagonist on the bound ceramides composition of a full thickness model (FTM) were analyzed. In FTMs, a decreased amount of bound ceramides was observed compared to native human skin. Furthermore, FTMs had a bound ceramide fraction which consisted mostly of unsaturated and shorter ceramides. The LXR antagonist had a normalizing effect on the FTM bound ceramide composition. The agonist exhibited minimal effects. We show that ceramide binding is a selective process, yet, still is contingent on lipid synthesized.
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Affiliation(s)
- Walter Boiten
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands.
| | - Richard Helder
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands.
| | - Jeroen van Smeden
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands.
| | - Joke Bouwstra
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands.
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Hypercholesterolemia in young adult APOE -/- mice alters epidermal lipid composition and impairs barrier function. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:976-984. [PMID: 30905828 DOI: 10.1016/j.bbalip.2019.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/19/2019] [Accepted: 03/18/2019] [Indexed: 12/20/2022]
Abstract
Long-term exposure to hypercholesterolemia induces the development of skin xanthoma's characterized by the accumulation of lipid-laden foam cells in humans and in mice. Early skin changes in response to hypercholesterolemia are however unknown. In this study, we investigated the skin lipid composition and associated barrier function in young adult low-density lipoprotein receptor knockout (LDLR-/-) and apolipoprotein E knockout (APOE-/-) mice, two commonly used hypercholesterolemic mouse models characterized by the accumulation of apolipoprotein B containing lipoproteins. No differences were observed on cholesterol content in the epidermis in LDLR-/- mice nor in the more extremely hypercholesterolemic APOE-/- mice. Interestingly, the free fatty acid profile in the APOE-/- epidermis shifted towards shorter and unsaturated chains. Genes involved in the synthesis of cholesterol and fatty acids were downregulated in APOE-/- skin suggesting a compensation for the higher influx of plasma lipids, most probably as cholesteryl esters. Importantly, in vivo transepidermal water loss and permeability studies with murine lipid model membranes revealed that the lipid composition of the APOE-/- skin resulted in a reduced skin barrier function. In conclusion, severe hypercholesterolemia associated with increased apolipoprotein B containing lipoproteins affects the epidermal lipid composition and its protective barrier.
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Ali A, Wahlgren M, Pedersen L, Engblom J. Will a water gradient in oral mucosa affect transbuccal drug absorption? J Drug Deliv Sci Technol 2018. [DOI: 10.1016/j.jddst.2018.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Harazim E, Vrkoslav V, Buděšínský M, Harazim P, Svoboda M, Plavka R, Bosáková Z, Cvačka J. Nonhydroxylated 1- O-acylceramides in vernix caseosa. J Lipid Res 2018; 59:2164-2173. [PMID: 30254076 PMCID: PMC6210899 DOI: 10.1194/jlr.m088864] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/21/2018] [Indexed: 01/22/2023] Open
Abstract
Vernix caseosa, the waxy substance that coats the skin of newborn babies, has an extremely complex lipid composition. We have explored these lipids and identified nonhydroxylated 1-O-acylceramides (1-O-ENSs) as a new class of lipids in vernix caseosa. These ceramides mostly contain saturated C11-C38 ester-linked (1-O) acyls, saturated C12-C39 amide-linked acyls, and C16-C24 sphingoid bases. Because their fatty acyl chains are frequently branched, numerous molecular species were separable and detectable by HPLC/MS: we found more than 2,300 molecular species, 972 of which were structurally characterized. The most abundant 1-O-ENSs contained straight-chain and branched fatty acyls with 20, 22, 24, or 26 carbons in the 1-O position, 24 or 26 carbons in the N position, and sphingosine. The 1-O-ENSs were isolated using multistep TLC and HPLC and they accounted for 1% of the total lipid extract. The molecular species of 1-O-ENSs were separated on a C18 HPLC column using an acetonitrile/propan-2-ol gradient and detected by APCI-MS, and the structures were elucidated by high-resolution and tandem MS. Medium-polarity 1-O-ENSs likely contribute to the cohesiveness and to the waterproofing and moisturizing properties of vernix caseosa.
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Affiliation(s)
- Eva Harazim
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, CZ-166 10 Praha 6, Czech Republic
- Department of Analytical Chemistry, Faculty of Science, Charles University, CZ-128 43 Praha 2, Czech Republic
| | - Vladimír Vrkoslav
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, CZ-166 10 Praha 6, Czech Republic
| | - Miloš Buděšínský
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, CZ-166 10 Praha 6, Czech Republic
| | - Petr Harazim
- Department of Concrete and Masonry Structures, Faculty of Civil Engineering, Czech Technical University in Prague, CZ-166 29 Praha 6, Czech Republic
| | - Martin Svoboda
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, CZ-166 10 Praha 6, Czech Republic
| | - Richard Plavka
- Department of Obstetrics and Gynecology, First Faculty of Medicine, Charles University and General University Hospital in Prague, CZ-128 00 Praha 2, Czech Republic
| | - Zuzana Bosáková
- Department of Analytical Chemistry, Faculty of Science, Charles University, CZ-128 43 Praha 2, Czech Republic
| | - Josef Cvačka
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, CZ-166 10 Praha 6, Czech Republic
- Department of Analytical Chemistry, Faculty of Science, Charles University, CZ-128 43 Praha 2, Czech Republic
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State of the art in Stratum Corneum research: The biophysical properties of ceramides. Chem Phys Lipids 2018; 216:91-103. [PMID: 30291856 DOI: 10.1016/j.chemphyslip.2018.09.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/10/2018] [Accepted: 09/29/2018] [Indexed: 11/20/2022]
Abstract
This review is summarizing an important part of the state of the art in stratum corneum research. A complete overview on discoveries about the general biophysical and physicochemical properties of the known ceramide species' is provided. The ceramides are one of the three major components of the lipid matrix and mainly govern its properties and structure. They are shown to exhibit very little redundancy, despite the minor differences in their chemical structure. The results are discussed, compared to each other as well as the current base of knowledge. New interesting aspects and concepts are concluded or suggested. A novel interpretation of the 3-dimensional structure of the lipid matrix and its influence on the barrier function will be discussed. The most important conclusion is the presentation of a new and up to date theoretical model of the nanostructure of the short periodicity phase. The model suggests three perpendicular layers: The rigid head group region, the rigid chain region and, a liquid-like overlapping middle layer. The general principle of the skin barrier function is highlighted in regard to this structure and the ceramides biophysical and physicochemical properties. As a result of these considerations, the entropy vs. enthalpy principle is introduced, shedding light on the function as well as the effectiveness of the skin barrier. Additionally, general ideas to effectively overcome this barrier principle for dermal and transdermal delivery of actives or how to use it for specific targeting of the stratum corneum are proposed.
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Lipids and the Permeability and Antimicrobial Barriers of the Skin. J Lipids 2018; 2018:5954034. [PMID: 30245886 PMCID: PMC6139190 DOI: 10.1155/2018/5954034] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 07/26/2018] [Indexed: 01/13/2023] Open
Abstract
The primary purpose of the epidermis of terrestrial vertebrates is to produce the stratum corneum, which serves as the interface between the organism and the environment. As such, the stratum corneum provides a permeability barrier which both limits water loss through the skin and provides a relatively tough permeability barrier. This provides for a degree of resistance to mechanical trauma and prevents or limits penetration of potentially harmful substances from the environment. The stratum corneum consists of an array of keratinized cells embedded in a lipid matrix. It is this intercellular lipid that determines the permeability of the stratum corneum. The main lipids here are ceramides, cholesterol, and fatty acids. In addition, the skin surface of mammals, including humans, is coated by a lipid film produced by sebaceous glands in the dermis and secreted through the follicles. Human sebum consists mainly of squalene, wax monoesters, and triglycerides with small proportions of cholesterol and cholesterol esters. As sebum passes through the follicles, some of the triglycerides are hydrolyzed by bacteria to liberate free fatty acids. Likewise, near the skin surface, where water becomes available, some of the ceramides are acted upon by an epithelial ceramidase to liberate sphingosine, dihydrosphingosine, and 6-hydroxysphingosine. Some of the free fatty acids, specifically lauric acid and sapienic acid, have been shown to have antibacterial, antifungal, and antiviral activity. Also, the long-chain bases have broad spectrum antibacterial activity.
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Nakaune-Iijima A, Sugishima A, Omura G, Kitaoka H, Tashiro T, Kageyama S, Hatta I. Topical treatments with acylceramide dispersions restored stratum corneum lipid lamellar structures in a reconstructed human epidermis model. Chem Phys Lipids 2018; 215:56-62. [DOI: 10.1016/j.chemphyslip.2018.05.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/02/2018] [Accepted: 05/19/2018] [Indexed: 11/30/2022]
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The long periodicity phase (LPP) controversy part I: The influence of a natural-like ratio of the CER[EOS] analogue [EOS]-br in a CER[NP]/[AP] based stratum corneum modelling system: A neutron diffraction study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1861:306-315. [PMID: 29924985 DOI: 10.1016/j.bbamem.2018.06.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 05/07/2018] [Accepted: 06/11/2018] [Indexed: 01/01/2023]
Abstract
This study used neutron diffraction to investigate a ceramide-[NP] C24/[AP] C24 /[EOS]-br C30/cholesterol/lignoceric acid (0.6: 0.3: 0.1: 0.7: 1) based stratum corneum modelling system. By adding specifically deuterated ceramides-[NP]-D3, [AP]-D3, and [EOS]-br-D3, detailed information on the lamellar and the nanostructure of the system was obtained. For the short periodicity phase a natural-like lamellar repeat distance of 5.47 ± 0.02 nm was observed, similar to the [NP]/[AP] base system without the [EOS]-br. Unlike in this system the ceramides here were slightly tilted, hinting towards a slightly less natural arrangement. Due to the deuteration it was possible to observe that the long ceramide chains were overlapping in the lamellar mid-plane. This is considered to be an important feature for the natural stratum corneum. Despite the presence of a ceramide [EOS] analogue - able to form a long phase arrangement - no distinct long periodicity phase was formed, despite a slightly higher than natural ω-acyl ceramide ratio of 10 mol%. The deuterated variant of this ceramide determined that the very long ceramide was integrated into the short periodicity phase, spanning multiple layers instead. The - compared to the base system - unchanged repeat distance highlights the stability of this structure. Furthermore, the localisation of the very long ceramide in the short periodicity phase indicates the possibility of a crosslinking effect and thus a multilayer stabilizing role for the ceramide [EOS]. It can be concluded, that additionally to the mere presence of ceramide-[EOS] more complex conditions have to be met in order to form this long phase. This has to be further investigated in the future.
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Abstract
AbstractThe outer layer of the skin, stratum corneum (SC) is an efficient transport barrier and it tolerates mechanical deformation. At physiological conditions, the majority of SC lipids are solid, while the presence of a small amount of fluid lipids is considered crucial for SC barrier and material properties. Here we use solid-state and diffusion nuclear magnetic resonance to characterize the composition and molecular dynamics of the fluid lipid fraction in SC model lipids, focusing on the role of the essential SC lipid CER EOS, which is a ceramide esterified omega-hydroxy sphingosine linoleate with very long chain. We show that both rigid and mobile structures are present within the same CER EOS molecule, and that the linoleate segments undergo fast isotropic reorientation while exhibiting extraordinarily slow self-diffusion. The characterization of this unusual self-assembly in SC lipids provides deepened insight into the molecular arrangement in the SC extracellular lipid matrix and the role of CER EOS linoleate in the healthy and diseased skin.
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Choe C, Schleusener J, Lademann J, Darvin ME. Human skin in vivo has a higher skin barrier function than porcine skin ex vivo-comprehensive Raman microscopic study of the stratum corneum. JOURNAL OF BIOPHOTONICS 2018; 11:e201700355. [PMID: 29460347 DOI: 10.1002/jbio.201700355] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/18/2018] [Indexed: 06/08/2023]
Abstract
Porcine skin is widely used as a human skin model in dermatology. For both, porcine stratum corneum (SC) ex vivo and human SC in vivo, the hydrogen bonding states of water, the secondary and tertiary structures of keratin, the natural moisturizing factor (NMF) concentrations and the intercellular lipids' (ICL) lateral organization are investigated depth-dependently using confocal Raman microscopy. The SC depth profiles show that porcine SC ex vivo is characterized by lower hydrogen bonding states of water (10%-30% SC depth), lower NMF concentration in the whole SC, more β-sheet form of keratin (10%-90% SC depth), more folded tertiary keratin structures (30%-70% SC depth) and higher hexagonal lateral packing order of ICL (10%-50% SC depth) compared to human SC in vivo. The results clearly show a higher value of skin barrier function of human SC in vivo than of porcine SC ex vivo. Thus, the human SC in vivo is less permeable for lipophilic and hydrophilic substances than porcine SC ex vivo. Considering the porcine SC as an ex vivo model of human SC in vivo, these findings should be taken into consideration.
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Affiliation(s)
- ChunSik Choe
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
- Kim Il Sung University, Ryongnam-Dong, Taesong District, Pyongyang, DPR Korea
| | - Johannes Schleusener
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
| | - Jürgen Lademann
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
| | - Maxim E Darvin
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Center of Experimental and Applied Cutaneous Physiology, Charitéplatz 1, 10117 Berlin, Germany
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Schmitt T, Gupta R, Lange S, Sonnenberger S, Dobner B, Hauß T, Rai B, Neubert RHH. Impact of the ceramide subspecies on the nanostructure of stratum corneum lipids using neutron scattering and molecular dynamics simulations. Part I: impact of CER[NS]. Chem Phys Lipids 2018; 214:58-68. [PMID: 29859142 DOI: 10.1016/j.chemphyslip.2018.05.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/18/2018] [Accepted: 05/28/2018] [Indexed: 11/19/2022]
Abstract
For this study mixtures based on the ceramides [NS] (NS = non-hydroxy-sphingosine) and [AP] (AP = α-hydroxy-phytosphingosine) in a 2:1 and 1:2 ratio, together with cholesterol and lignoceric acid, were investigated. These mixtures are modelling the uppermost skin layer, the stratum corneum. Neutron diffraction, utilizing specifically deuterated ceramide molecules, was used to obtain a maximum amount of experimental detail. Highly detailed molecular dynamics simulations were used to generate even more information from the experimental data. It was possible to observe a single lamellar phase for both systems. They had a lamellar repeat distance of 5.43 ± 0.05 nm for the [NS]/[AP] 2:1 and a slightly shorter one of 5.34 ± 0.05 nm for the 1:2 system. The structure and water content was uninfluenced by excess humidity. Both the experimental and simulation data indicated slightly tilted ceramides, with their C24 chains overlapping in the lamellar mid-plane. This arrangement is well comparable to systems investigated before. The structure of both systems, except for the differing repeat distance, looks similar at first. However, on a smaller scale there were various distinct differences, demonstrating only low redundancy between the different ceramide species, despite only minor chemical differences. The mainly ceramide [AP] determined 1:2 system has a slightly smaller repeat distance. This is a result of a tighter arrangement of the lipids chain along the bilayer normal and increased overlapping of the long chains in the lamellar middle. For the CER[NS] some novel features could be shown, despite it being the overall most investigated ceramide. These include the low adaptability to changed lateral interactions, leading to an increased chain opening. This effect could explain its low miscibility with other lipids. The investigated model systems allows it to directly compare results from the literature which have used ceramide [NS] to the most recent studies using the phytosphingosine ceramides such as ceramide [AP].
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Affiliation(s)
- Thomas Schmitt
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), Weinbergweg 23, 06120 Halle/Saale, Germany
| | - Rakesh Gupta
- Physical Science Research Area, TCS Research, Tata Research Development and Design Centre, Tata Consultancy Services, 54B, Hadapsar Industrial Estate, Pune, 411013, India
| | - Stefan Lange
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany
| | - Stefan Sonnenberger
- Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU), Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Bodo Dobner
- Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU), Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Thomas Hauß
- Helmholtz-Zentrum Berlin für Materialien und Energie (HZB), Hahn-Meitner-Platz 1, 14109, Berlin, Germany
| | - Beena Rai
- Physical Science Research Area, TCS Research, Tata Research Development and Design Centre, Tata Consultancy Services, 54B, Hadapsar Industrial Estate, Pune, 411013, India
| | - Reinhard H H Neubert
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), Weinbergweg 23, 06120 Halle/Saale, Germany; Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
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38
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Niehues H, Bouwstra JA, El Ghalbzouri A, Brandner JM, Zeeuwen PLJM, van den Bogaard EH. 3D skin models for 3R research: The potential of 3D reconstructed skin models to study skin barrier function. Exp Dermatol 2018. [DOI: 10.1111/exd.13531] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Hanna Niehues
- Department of Dermatology; Radboud university medical center (Radboudumc); Radboud Institute for Molecular Life Sciences (RIMLS); Nijmegen The Netherlands
| | - Joke A. Bouwstra
- Division of Drug Delivery Technology; Cluster BioTherapeutics; Leiden Academic Centre for Drug Research; Leiden University; Leiden The Netherlands
| | | | - Johanna M. Brandner
- Department of Dermatology and Venerology; University Hospital Hamburg-Eppendorf; Hamburg Germany
| | - Patrick L. J. M. Zeeuwen
- Department of Dermatology; Radboud university medical center (Radboudumc); Radboud Institute for Molecular Life Sciences (RIMLS); Nijmegen The Netherlands
| | - Ellen H. van den Bogaard
- Department of Dermatology; Radboud university medical center (Radboudumc); Radboud Institute for Molecular Life Sciences (RIMLS); Nijmegen The Netherlands
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Zhang Z, Lunter DJ. Confocal Raman microspectroscopy as an alternative method to investigate the extraction of lipids from stratum corneum by emulsifiers and formulations. Eur J Pharm Biopharm 2018; 127:61-71. [PMID: 29428793 DOI: 10.1016/j.ejpb.2018.02.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 11/24/2022]
Abstract
The purpose of this study was to investigate the impact of emulsifiers and formulations on intercellular lipids of porcine stratum corneum (SC) and evaluate confocal Raman microscopy (CRM) as an alternative method in this research context. To this end, four different formulations were used: three conventional creams that contained ionic and/or non-ionic emulsifiers and one surfactants-free emulsion stabilized by a polymeric emulsifier. Additionally, all emulsifiers were tested in aqueous solution/dispersion in the respective concentrations as present in the formulations. CRM and HPTLC were used to analyse changes in SC lipid content after treatment. Furthermore, lipid extraction was visualized by fluorescence staining and SC thickness was measured by CRM and light microscopy. Various emulsifiers and emulsifier mixtures showed different impact on SC lipid content and SC thickness, while none of the tested formulations had any effect on SC lipids. Emulsifiers and their mixtures that reduced the lipids content also reduced SC thickness, indicating lipid extraction is the reason for SC thinning. Results from CRM and conventional methods showed a strong positive correlation for both lipid content and SC thickness measurements. With easy sample preparation and fast analytical readout, CRM has the potential to be a standardized analytical method for skin lipids investigation.
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Affiliation(s)
- Ziwei Zhang
- University of Tuebingen, Pharmaceutical Technology, Tuebingen, Germany
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40
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Altered lipid properties of the stratum corneum in Canine Atopic Dermatitis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:526-533. [DOI: 10.1016/j.bbamem.2017.11.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/17/2017] [Accepted: 11/20/2017] [Indexed: 12/20/2022]
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Schmitt T, Lange S, Dobner B, Sonnenberger S, Hauß T, Neubert RHH. Investigation of a CER[NP]- and [AP]-Based Stratum Corneum Modeling Membrane System: Using Specifically Deuterated CER Together with a Neutron Diffraction Approach. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1742-1749. [PMID: 28949139 DOI: 10.1021/acs.langmuir.7b01848] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Neutron diffraction was used as a tool to investigate the lamellar as well as molecular nanostructure of ceramide-[NP]/ceramide-[AP]/cholesterol/lignoceric acid model systems with a nativelike 2:1 ratio and a 1:2 ratio to study the influence of the ceramide-[AP]. By using mixtures together with cholesterol and free fatty acids as well as a humidity and temperature chamber while measuring, natural conditions were simulated as closely as possible. Despite its simplicity, the system simulated the native stratum corneum lipid matrix fairly closely, showing a similar lamellar thickness with a repeat distance of 5.45 ± 0.1 nm and a similar arrangement with overlapping long C24 chains. Furthermore, despite the very minor chemical difference between ceramide-[NP] and ceramide-[AP], which is only a single OH group, it was possible to demonstrate substantial differences between the structural influence of the two ceramides. Ceramide-[AP] could be concluded to be arranged in such a way that its C24 chain in both ratios is somehow shorter than that of ceramide-[NP], not overlapping as much with the opposite lamellar leaflet. Furthermore, in the unnatural 1:2 ratio, the higher ceramide-[AP] content causes an increased tilt of the ceramide acyl chains. This leads to even less overlapping within the lamellar midplane, whereas the repeat distance stays the same as for the ceramide-[NP]-rich system. In this nativelike 2:1 ratio, the chains are arranged mostly straight, and the long C24 chains show a broad overlapping region in the lamellar midplane.
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Affiliation(s)
- Thomas Schmitt
- Institute of Applied Dermatopharmacy, Martin Luther University Halle-Wittenberg (IADP) , Weinbergweg 23, 06120 Halle/Saale, Germany
| | - Stefan Lange
- Institute of Medical Physics and Biophysics, University of Leipzig , Härtelstraße 16-18, 04107 Leipzig, Germany
| | - Bodo Dobner
- Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU) , Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Stefan Sonnenberger
- Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU) , Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Thomas Hauß
- Helmholtz-Zentrum Berlin für Materialien und Energie (HZB) , Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - Reinhard H H Neubert
- Institute of Applied Dermatopharmacy, Martin Luther University Halle-Wittenberg (IADP) , Weinbergweg 23, 06120 Halle/Saale, Germany
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Schmitt T, Lange S, Sonnenberger S, Dobner B, Demé B, Neubert RHH, Gooris G, Bouwstra JA. Determination of the influence of C24 D/(2R)- and L/(2S)-isomers of the CER[AP] on the lamellar structure of stratum corneum model systems using neutron diffraction. Chem Phys Lipids 2017; 209:29-36. [PMID: 29103906 DOI: 10.1016/j.chemphyslip.2017.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 11/01/2017] [Accepted: 11/01/2017] [Indexed: 10/18/2022]
Abstract
This study was able to investigate the different influence of the d- and l-ceramide [AP] on the lamellar as well as molecular nanostructure of stratum corneum simulating lipid model mixtures. In this case, neutron diffraction together with specifically deuterated ceramide was used as an effective tool to investigate the lamellar and the molecular nanostructure of the mixtures. It could clearly be demonstrated, that both isomers show distinctly different characteristics, even though the variation between both is only a single differently arranged OH-group. The l-ceramide [AP] promotes a crystalline like phase behaviour even if mixed with ceramide [NP], cholesterol and free fatty acids. The d-ceramide [AP] only shows crystalline-like features if mixed only with cholesterol and free fatty acids but adopts a native-like behaviour if additionally mixed with ceramide [NP]. It furthermore demonstrates that the l-ceramide [AP] should not be used for any applications concerning ceramide substitution. It could however possibly serve its own purpose, if this crystalline like behaviour has some kind of positive influence on the SC or can be utilized for any practical applications. The results obtained in this study demonstrate that the diastereomers of ceramide [AP] are an attractive target for further research because their influence on the lamellar as well as the nanostructure is exceptionally strong. Additionally, the results furthermore show a very strong influence on hydration of the model membrane. With these properties, the d-ceramide [AP] could be effectively used to simulate native like behaviour even in very simple mixtures and could also have a strong impact on the native stratum corneum as well as high relevance for dermal ceramide substitution. The unnatural l-ceramide [AP] on the other hand should be investigated further, to assess its applicability.
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Affiliation(s)
- Thomas Schmitt
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), Weinbergweg 23, 06120 Halle/Saale, Germany
| | - Stefan Lange
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany; Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU), Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Stefan Sonnenberger
- Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU), Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Bodo Dobner
- Institute of Pharmacy, Martin Luther University Halle-Wittenberg (MLU), Wolfgang-Langenbeck-Str. 4, 06120 Halle/Saale, Germany
| | - Bruno Demé
- Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, 38042 Grenoble CEDEX 9, France
| | - Reinhard H H Neubert
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), Weinbergweg 23, 06120 Halle/Saale, Germany.
| | - Gert Gooris
- Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Max Planckweg 8 2333 CE Leiden, The Netherlands
| | - Joke A Bouwstra
- Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Max Planckweg 8 2333 CE Leiden, The Netherlands
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Wertz PW. Naturally occurring ω-Hydroxyacids. Int J Cosmet Sci 2017; 40:31-33. [PMID: 28994119 DOI: 10.1111/ics.12432] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/05/2017] [Indexed: 01/05/2023]
Abstract
ω-Hydroxyacids are fatty acids bearing a hydroxyl group on the terminal carbon. They are found in mammals and higher plants and are often involved in providing a permeability barrier, the primary purpose of which is to reduce water loss. Some ω-hydroxyacid derivatives may be involved in waterproofing and signalling. The purpose of this review was to survey the known natural sources of ω-hydroxyacids. ω-Hydroxyacids are produced by two different P450-dependent mechanisms. The longer (30-34 carbons) ω-hydroxyacids are produced by chain extension from palmitic acid until the chain extends across the membrane in which the extension is taking place, and then the terminal carbon is hydroxylated. Shorter fatty acids can be hydroxylated directly to produce C16 and C18 ω-hydroxyacids found in plants and 20-eicosatetraenoic acid (20-HETE) by a different P450. The C16 and C18 ω-hydroxyacids are components of polymers in plants. The long-chain ω-hydroxyacids are found in epidermal sphingolipids, in giant-ring lactones from the sebum of members of the equidae, as a component of meibum and in carnauba wax and wool wax.
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Affiliation(s)
- P W Wertz
- 1412 Laurel Street, Iowa City, IA, 52242, USA
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Yu Y, Li L, Li H, Yu X, Zhang Y, Wang Q, Zhou Z, Gao D, Ye H, Lin B, Ma R. In vivo assessment of dermal adhesion, penetration, and bioavailability of tetrabromobisphenol A. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 228:305-310. [PMID: 28550799 DOI: 10.1016/j.envpol.2017.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 05/02/2017] [Accepted: 05/03/2017] [Indexed: 06/07/2023]
Abstract
Individuals are exposed to brominated flame retardants (BFRs), including tetrabromobisphenol A (TBBPA), on a daily basis because of their widespread usage. These compounds may have adverse effects on human health. In the present study, dermal absorption experiments were conducted in vivo to predict the adhesion, penetration, and bioavailability of TBBPA. TBBPA was administered to Wistar rats for 6 h by repeated dermal exposure at doses of 20, 60, 200, and 600 mg of TBBPA per kg of body weight (bw). The skin adhesion coefficient (AC) was calculated using a difference-value method and ranged from 0.12 to 3.25 mg/cm2 and 0.1 to 2.56 mg/cm2 for the male and female rats, respectively. The adhesion rate was 70.92%. According to Fick's first law of diffusion, the diffusion constant (D) was 1.4 × 10-4 cm2/h and the permeation coefficient (Kp) was 1.26 × 10-5 cm/h for TBBPA. TBBPA levels in the blood, urine, and feces of the male rats were significantly higher than those in the female rats. The dermal bioavailability of TBBPA was 24.71% for male rats and 20.05% for female rats 24 h after exposure.
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Affiliation(s)
- Yunjiang Yu
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China.
| | - Liangzhong Li
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China
| | - Hongyan Li
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China
| | - Xiaowei Yu
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China
| | - Yanping Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Qiong Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Environmental Health and Related Product Safety, China CDC, Beijing 100021, China
| | - Zhixiang Zhou
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing 100124, China.
| | - Dandan Gao
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Hao Ye
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Bigui Lin
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China
| | - Ruixue Ma
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Center for Environmental Health Research, South China Institute of Environmental Sciences, MEP, Guangzhou 510535, China
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Koppes SA, Ljubojević Hadžavdić S, Jakasa I, Franceschi N, Riethmüller C, Jurakić Tončic R, Marinovic B, Raj N, Rawlings AV, Voegeli R, Lane ME, Haftek M, Frings‐Dresen MH, Rustemeyer T, Kezic S. Effect of allergens and irritants on levels of natural moisturizing factor and corneocyte morphology. Contact Dermatitis 2017; 76:287-295. [PMID: 28295421 PMCID: PMC5836858 DOI: 10.1111/cod.12770] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 01/04/2017] [Accepted: 01/05/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND The irritant sodium lauryl sulfate (SLS) is known to cause a decrease in the stratum corneum level of natural moisturizing factor (NMF), which in itself is associated with changes in corneocyte surface topography. OBJECTIVE To explore this phenomenon in allergic contact dermatitis. METHODS Patch testing was performed on patients with previously positive patch test reactions to potassium dichromate (Cr), nickel sulfate (Ni), methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI), or p-phenylenediamine. Moreover, a control (pet.) patch and an irritant (SLS) patch were applied. After 3 days, the stratum corneum from tested sites was collected, and NMF levels and corneocyte morphology, expressed as the amount of circular nanosize objects, quantified according to the Dermal Texture Index (DTI), were determined. RESULTS Among allergens, only MCI/MI reduced NMF levels significantly, as did SLS. Furthermore, only MCI/MI caused remarkable changes at the microscopic level; the corneocytes were hexagonal-shaped with pronounced cell borders and a smoother surface. The DTI was increased after SLS exposure but not after allergen exposure. CONCLUSIONS MCI/MI significantly decreased NMF levels, similarly to SLS. The altered corneocyte morphology suggests that skin barrier damage plays a role in the pathogenesis of MCI/MI contact allergy. The DTI seems to differentiate reactions to SLS from those to the allergens tested, as SLS was the only agent that caused a DTI increase.
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Affiliation(s)
- Sjors A. Koppes
- Academic Medical Center, Department: Coronel institute of Occupational HealthAmsterdam Public Health Research Institute1105 AZ AmsterdamThe Netherlands
- Department of Dermatology‐AllergologyVU University Medical Centre1081 HV AmsterdamThe Netherlands
| | - Suzana Ljubojević Hadžavdić
- Department of Dermatology and VenereologyUniversity Hospital Centre Zagreb and University of Zagreb School of Medicine10000ZagrebCroatia
| | - Ivone Jakasa
- Faculty of Food Technology and Biotechnology, Laboratory for Analytical Chemistry, Department of Chemistry and BiochemistryUniversity of Zagreb10000ZagrebCroatia
| | - Nika Franceschi
- Department of Dermatology and Venereology, University Clinical Hospital Centre ‘Sestre Milosrdnice’10000ZagrebCroatia
| | - Christoph Riethmüller
- Centre for Nanotechnology, Serend‐ip GmbHCentre for Nanotechnology48149MünsterGermany
| | - Ružica Jurakić Tončic
- Department of Dermatology and VenereologyUniversity Hospital Centre Zagreb and University of Zagreb School of Medicine10000ZagrebCroatia
| | - Branka Marinovic
- Department of Dermatology and VenereologyUniversity Hospital Centre Zagreb and University of Zagreb School of Medicine10000ZagrebCroatia
| | - Nidhin Raj
- Skin Research Laboratory, Department of PharmaceuticsUniversity College LondonWC1N 1AXLondonUK
| | - Anthony V. Rawlings
- Skin Research Laboratory, Department of PharmaceuticsUniversity College LondonWC1N 1AXLondonUK
| | | | - Majella E. Lane
- Skin Research Laboratory, Department of PharmaceuticsUniversity College LondonWC1N 1AXLondonUK
| | - Marek Haftek
- Laboratory of Tissue Biology and Therapeutic EngineeringCNRS and University of LyonUMR 5305LyonFrance
| | - Monique H.W. Frings‐Dresen
- Academic Medical Center, Department: Coronel institute of Occupational HealthAmsterdam Public Health Research Institute1105 AZ AmsterdamThe Netherlands
| | - Thomas Rustemeyer
- Department of Dermatology‐AllergologyVU University Medical Centre1081 HV AmsterdamThe Netherlands
| | - Sanja Kezic
- Academic Medical Center, Department: Coronel institute of Occupational HealthAmsterdam Public Health Research Institute1105 AZ AmsterdamThe Netherlands
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46
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Tessema EN, Gebre-Mariam T, Neubert RHH, Wohlrab J. Potential Applications of Phyto-Derived Ceramides in Improving Epidermal Barrier Function. Skin Pharmacol Physiol 2017; 30:115-138. [PMID: 28407621 DOI: 10.1159/000464337] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 02/17/2017] [Indexed: 12/31/2022]
Abstract
The outer most layer of the skin, the stratum corneum, consists of corneocytes which are coated by a cornified envelope and embedded in a lipid matrix of ordered lamellar structure. It is responsible for the skin barrier function. Ceramides (CERs) are the backbone of the intercellular lipid membranes. Skin diseases such as atopic dermatitis and psoriasis and aged skin are characterized by dysfunctional skin barrier and dryness which are associated with reduced levels of CERs. Previously, the effectiveness of supplementation of synthetic and animal-based CERs in replenishing the depleted natural skin CERs and restoring the skin barrier function have been investigated. Recently, however, the barrier function improving effect of plant-derived CERs has attracted much attention. Phyto-derived CERs (phytoCERs) are preferable due to their assumed higher safety as they are mostly isolated from dietary sources. The beneficial effects of phytoCER-based oral dietary supplements for skin hydration and skin barrier reinforcement have been indicated in several studies involving animal models as well as human subjects. Ingestible dietary supplements containing phytoCERs are also widely available on the market. Nonetheless, little effort has been made to investigate the potential cosmetic applications of topically administered phytoCERs. Therefore, summarizing the foregoing investigations and identifying the gap in the scientific data on plant-derived CERs intended for skin-health benefits are of paramount importance. In this review, an attempt is made to synthesize the information available in the literature regarding the effects of phytoCER-based oral dietary supplements on skin hydration and barrier function with the underlying mechanisms.
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Affiliation(s)
- Efrem N Tessema
- Department of Pharmaceutical Technology and Biopharmaceutics, Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
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Mieremet A, Rietveld M, Absalah S, van Smeden J, Bouwstra JA, El Ghalbzouri A. Improved epidermal barrier formation in human skin models by chitosan modulated dermal matrices. PLoS One 2017; 12:e0174478. [PMID: 28333992 PMCID: PMC5363943 DOI: 10.1371/journal.pone.0174478] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 03/09/2017] [Indexed: 01/15/2023] Open
Abstract
Full thickness human skin models (FTMs) contain an epidermal and a dermal equivalent. The latter is composed of a collagen dermal matrix which harbours fibroblasts. Current epidermal barrier properties of FTMs do not fully resemble that of native human skin (NHS), which makes these human skin models less suitable for barrier related studies. To further enhance the resemblance of NHS for epidermal morphogenesis and barrier formation, we modulated the collagen dermal matrix with the biocompatible polymer chitosan. Herein, we report that these collagen-chitosan FTMs (CC-FTMs) possess a well-organized epidermis and maintain both the early and late differentiation programs as in FTMs. Distinctively, the epidermal cell activation is reduced in CC-FTMs to levels observed in NHS. Dermal-epidermal interactions are functional in both FTM types, based on the formation of the basement membrane. Evaluation of the barrier structure by the organization of the extracellular lipid matrix of the stratum corneum revealed an elongated repeat distance of the long periodicity phase. The ceramide composition exhibited a higher resemblance of the NHS, based on the carbon chain-length distribution and subclass profile. The inside-out barrier functionality indicated by the transepidermal water loss is significantly improved in the CC-FTMs. The expression of epidermal barrier lipid processing enzymes is marginally affected, although more restricted to a single granular layer. The novel CC-FTM resembles the NHS more closely, which makes them a promising tool for epidermal barrier related studies.
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Affiliation(s)
- Arnout Mieremet
- Department of Dermatology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Marion Rietveld
- Department of Dermatology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Samira Absalah
- Division of Drug Delivery Technology, Leiden Academic Center for Drug Research, Leiden University, Leiden, the Netherlands
| | - Jeroen van Smeden
- Division of Drug Delivery Technology, Leiden Academic Center for Drug Research, Leiden University, Leiden, the Netherlands
| | - Joke A. Bouwstra
- Division of Drug Delivery Technology, Leiden Academic Center for Drug Research, Leiden University, Leiden, the Netherlands
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48
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Lin MH, Miner JH, Turk J, Hsu FF. Linear ion-trap MS n with high-resolution MS reveals structural diversity of 1-O-acylceramide family in mouse epidermis. J Lipid Res 2017; 58:772-782. [PMID: 28154204 DOI: 10.1194/jlr.d071647] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 01/27/2017] [Indexed: 12/30/2022] Open
Abstract
1-O-acylceramide is a new class of epidermal cer-amide (Cer) found in humans and mice. Here, we report an ESI linear ion-trap (LIT) multiple-stage MS (MSn) approach with high resolution toward structural characterization of this lipid family isolated from mice. Molecular species desorbed as the [M + H]+ ions were subjected to LIT MS2 to yield predominately the [M + H - H2O]+ ions, followed by MS3 to cleave the 1-O-acyl residue to yield the [M + H - H2O - (1-O-FA)]+ ions. The structures of the N-acyl chain and long-chain base (LCB) of the molecule were determined by MS4 on [M + H - H2O - (1-O-FA)]+ ions that yielded multiple sets of specific ions. Using this approach, isomers varied in the 1-O-acyl (from 14:0- to 30:0-O-acyl) and N-acyl chains (from 14:0- to 34:1-N-acyl) with 18:1-sphingosine as the major LCB were found for the entire family. Minor isomers consisting of 16:1-, 17:1-, 18:2-, and 19:1-sphingosine LCBs with odd fatty acyl chain or with monounsaturated N- or O-fatty acyl substituents were also identified. An estimation of more than 700 1-O-acylceramide species, largely isobaric isomers, are present, underscoring the complexity of this Cer family.
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Affiliation(s)
- Meei-Hua Lin
- Division of Nephrology Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Jeffrey H Miner
- Division of Nephrology Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - John Turk
- Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Fong-Fu Hsu
- Mass Spectrometry Resource, Division of Endocrinology, Diabetes, Metabolism, and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO.
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Fernandes RA, Kattanguru P, Gholap SP, Chaudhari DA. Recent advances in the Overman rearrangement: synthesis of natural products and valuable compounds. Org Biomol Chem 2017; 15:2672-2710. [DOI: 10.1039/c6ob02625g] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This review documents the reports since 2005 on the Overman rearrangement, an important C–N bond forming reaction that has been profoundly used in the synthesis of natural products, synthetic intermediates, building blocks and valuable compounds.
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Affiliation(s)
- Rodney A. Fernandes
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Pullaiah Kattanguru
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Sachin P. Gholap
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Dipali A. Chaudhari
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
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50
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Moore TC, Iacovella CR, Hartkamp R, Bunge AL, McCabe C. A Coarse-Grained Model of Stratum Corneum Lipids: Free Fatty Acids and Ceramide NS. J Phys Chem B 2016; 120:9944-58. [PMID: 27564869 PMCID: PMC5287476 DOI: 10.1021/acs.jpcb.6b08046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Ceramide (CER)-based biological membranes are used both experimentally and in simulations as simplified model systems of the skin barrier. Molecular dynamics studies have generally focused on simulating preassembled structures using atomistically detailed models of CERs, which limit the system sizes and time scales that can practically be probed, rendering them ineffective for studying particular phenomena, including self-assembly into bilayer and lamellar superstructures. Here, we report on the development of a coarse-grained (CG) model for CER NS, the most abundant CER in human stratum corneum. Multistate iterative Boltzmann inversion is used to derive the intermolecular pair potentials, resulting in a force field that is applicable over a range of state points and suitable for studying ceramide self-assembly. The chosen CG mapping, which includes explicit interaction sites for hydroxyl groups, captures the directional nature of hydrogen bonding and allows for accurate predictions of several key structural properties of CER NS bilayers. Simulated wetting experiments allow the hydrophobicity of CG beads to be accurately tuned to match atomistic wetting behavior, which affects the whole system, since inaccurate hydrophobic character is found to unphysically alter the lipid packing in hydrated lamellar states. We find that CER NS can self-assemble into multilamellar structures, enabling the study of lipid systems more representative of the multilamellar lipid structures present in the skin barrier. The coarse-grained force field derived herein represents an important step in using molecular dynamics to study the human skin barrier, which gives a resolution not available through experiment alone.
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Affiliation(s)
- Timothy C. Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
| | - Christopher R. Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
| | - Remco Hartkamp
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
| | - Annette L. Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO 80401
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235
- Vanderbilt University Multiscale Modeling and Simulation (MuMS) Facility, Nashville, TN 37235
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235
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