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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Fernandes E, Lopes CM, Lúcio M. Lipid Biomimetic Models as Simple Yet Complex Tools to Predict Skin Permeation and Drug-Membrane Biophysical Interactions. Pharmaceutics 2024; 16:807. [PMID: 38931927 PMCID: PMC11207520 DOI: 10.3390/pharmaceutics16060807] [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: 05/10/2024] [Revised: 06/07/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024] Open
Abstract
The barrier function of the skin is primarily determined by its outermost layer, the Stratum Corneum (SC). The SC consists of corneocytes embedded in a lipid matrix composed mainly of ceramides, cholesterol, and free fatty acids in equimolar proportions and is organised in a complex lamellar structure with different periodicities and lateral packings. This matrix provides a diffusion pathway across the SC for bioactive compounds that are administered to the skin. In this regard, and as the skin administration route has grown in popularity, there has been an increase in the use of lipid mixtures that closely resemble the SC lipid matrix, either for a deeper biophysical understanding or for pharmaceutical and cosmetic purposes. This review focuses on a systematic analysis of the main outcomes of using lipid mixtures as SC lipid matrix models for pharmaceutical and cosmetic purposes. Thus, a methodical evaluation of the main outcomes based on the SC structure is performed, as well as the main recent developments in finding suitable new in vitro tools for permeation testing based on lipid models.
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Affiliation(s)
- Eduarda Fernandes
- CF-UM-UP—Centro de Física das Universidades do Minho e Porto, Departamento de Física, Universidade do Minho, 4710-057 Braga, Portugal
| | - Carla M. Lopes
- FFP-I3ID—Instituto de Investigação, Inovação e Desenvolvimento, FP-BHS—Biomedical and Health Sciences Research Unit, Faculdade de Ciências da Saúde, Universidade Fernando Pessoa, 4200–150 Porto, Portugal;
- UCIBIO—Applied Molecular Biosciences Unit, MedTech–Laboratory of Pharmaceutical Technology, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
| | - Marlene Lúcio
- CF-UM-UP—Centro de Física das Universidades do Minho e Porto, Departamento de Física, Universidade do Minho, 4710-057 Braga, Portugal
- CBMA—Centro de Biologia Molecular e Ambiental, Departamento de Biologia, Universidade do Minho, 4710-057 Braga, Portugal
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3
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Jiang Z, Liu S, Yuan S, Zhang H, Yuan S. Models of the Three-Component Bilayer of Stratum Corneum: A Molecular Simulation Study. J Phys Chem B 2024; 128:3833-3843. [PMID: 38603528 DOI: 10.1021/acs.jpcb.3c08461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
The construction of the stratum corneum (SC) is crucial to the problems of transdermal drug delivery. SC consists of the keratinocyte layers and the lipid matrix surrounding it. Among them, the lipid matrix is the barrier for many exogenous molecules, mainly composed of ceramides (CERs), free fatty acids (FFA), and cholesterol (CHOL). In this work, we developed single-component (CERs, CER-NS, and CER-EOS) and six three-component models, and each model was simulated by using the GROMOS-54A7 force field. Short-period phase (SPP) and long-period phase (LPP) systems were established separately, and area per lipid (APL), thickness, order of carbon chain (SCD), and density distribution were analyzed. The transition of CER-NS and CER-EOS in LPP was observed. The results of hydrogen bonds in the lipid systems indicated that a strong hydrogen-bond network was formed between the skin-lipid bilayers. Umbrella sampling method simulations were performed to calculate the free energy change of ethanol moving into the skin-lipid bilayer. The results revealed that ethanol molecules pulled some water molecules into the membrane when they passed through SPP-1. Our findings provided some insights and models of the stratum corneum that could be used for the subsequent mechanism of macromolecule permeation through membranes in drugs, cosmetics, and so on.
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Affiliation(s)
- Zhaoli Jiang
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100, P. R. China
| | - Shasha Liu
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100, P. R. China
- College of Chemistry and Chemical Engineering, Qilu Normal University, Jinan, Shandong 250013, P. R. China
| | - Shideng Yuan
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100, P. R. China
| | - Heng Zhang
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100, P. R. China
| | - Shiling Yuan
- Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan, Shandong 250100, P. R. China
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4
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Bryant SJ, Garvey CJ, Darwish TA, Georgii R, Bryant G. Molecular interactions with bilayer membrane stacks using neutron and X-ray diffraction. Adv Colloid Interface Sci 2024; 326:103134. [PMID: 38518550 DOI: 10.1016/j.cis.2024.103134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 03/14/2024] [Accepted: 03/14/2024] [Indexed: 03/24/2024]
Abstract
Lamellar unit cell reconstruction from neutron and X-ray diffraction data provides information about the disposition and position of molecules and molecular segments with respect to the bilayer. When supplemented with the judicious use of molecular deuteration, the technique probes the molecular interactions and conformations within the bilayer membrane and the water layer which constitute the crystallographic unit cell. The perspective is model independent, and potentially, with a higher degree of resolution than is available with other techniques. In the case of neutron diffraction the measurement consists of carefully normalised diffracted intensity under conditions of contrast variation of the water layer. The subsequent Fourier reconstruction of the unit cell is made using the phase information from variation of peak intensities with contrast. Although the phase problem is not as easily solved for the corresponding X-ray measurements, an intuitive approach can often suffice. Here we discuss the two complimentary techniques as probes of scattering length density profiles of a bilayer, and how such a perspective provides information about the location and orientation of molecules within or between lipid bilayers. Within the basic paradigm of lamellar phases this method has provided, for example, detailed insights into the location and interaction of cryoprotectants and stress proteins, of the mechanisms of actions of viral proteins, antimicrobial compounds and drugs, and the underlying structure of the stratum corneum. In this paper we review these techniques and provide examples of the systems that have been examined. We finish with a future outlook on the use of these techniques to improve our understanding of the interactions of membranes with biomolecules.
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Affiliation(s)
- Saffron J Bryant
- School of Science, College of STEM, RMIT University, Melbourne, Australia
| | - Christopher J Garvey
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstraße 1, 85748 Garching, Germany
| | - Tamim A Darwish
- National Deuteration Facility, Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia; Faculty of Science and Technology, University of Canberra, ACT 2617, Australia
| | - Robert Georgii
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstraße 1, 85748 Garching, Germany
| | - Gary Bryant
- School of Science, College of STEM, RMIT University, Melbourne, Australia.
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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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6
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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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7
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Nagle JF. Understanding the phase behavior of a protobiomembrane. Phys Rev E 2023; 107:064408. [PMID: 37464660 DOI: 10.1103/physreve.107.064408] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 06/13/2023] [Indexed: 07/20/2023]
Abstract
The rich thermotropic behavior of lipid bilayers is addressed using phenomenological theory informed by many experiments. The most recent experiment not yet addressed by theory has shown that the tilt modulus in DMPC lipid bilayers decreases dramatically as the temperature is lowered toward the main transition temperature T_{M}. It is shown that this behavior can be understood by introducing a simple free energy functional for tilt that couples to the area per molecule. This is combined with a chain melting free energy functional in which the area is the primary order parameter that is the driver of the main transition. Satisfactory agreement with experiment is achieved with values of the model parameters determined by experiments, but the transition is directly into the gel phase. The theory is then extended to include the enigmatic ripple phase by making contact with the most recent experimentally determined ripple structure.
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Affiliation(s)
- John F Nagle
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
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8
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Roy S, Ho JCS, Teo DLC, Gupta S, Nallani M. Biomimetic Stratum Corneum Liposome Models: Lamellar Organization and Permeability Studies. MEMBRANES 2023; 13:135. [PMID: 36837639 PMCID: PMC9962386 DOI: 10.3390/membranes13020135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/18/2023] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
The stratum corneum (SC), the outer layer of the skin, plays a crucial role as a barrier protecting the underlying cells from external stress. The SC comprises three key components: ceramide (CER), free fatty acid (FFA), and cholesterol, along with small fractions of cholesterol sulfate and cholesterol ester. In order to gain a deeper understanding about the interdependence of the two major components, CER and FFA, on the organizational, structural, and functional properties of the SC layer, a library of SC lipid liposome (SCLL) models was developed by mixing CER (phytosphingosine or sphingosine), FFA (oleic acid, palmitic acid, or stearic acid), cholesterol, and cholesterol sulfate. Self-assembly of the SC lipids into lamellar phases was first confirmed by small-angle X-ray scattering. Short periodicity and long periodicity phases were identified for SCLLs containing phytosphingosines and sphingosine CERs, respectively. Furthermore, unsaturation in the CER acyl and FFA chains reduced the lipid conformational ordering and packing density of the liposomal bilayer, which were measured by differential scanning calorimetry and Fourier transform infrared spectroscopy. The introduction of unsaturation in the CER and/or FFA chains also impacted the lamellar integrity and permeability. This extensive library of SCLL models exhibiting physiologically relevant lamellar phases with defined structural and functional properties may potentially be used as a model system for screening pharmaceuticals or cosmetic agents.
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Affiliation(s)
- Susmita Roy
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University, Singapore 637553, Singapore
| | - James C. S. Ho
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University, Singapore 637553, Singapore
| | - Douglas L. C. Teo
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University, Singapore 637553, Singapore
| | - Shikhar Gupta
- Procter & Gamble International Operations SA SG Branch, Singapore 138547, Singapore
| | - Madhavan Nallani
- Center for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University, Singapore 637553, Singapore
- ACM Biolabs Pte Ltd., Singapore 638075, Singapore
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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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10
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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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11
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Shamaprasad P, Moore TC, Xia D, Iacovella CR, Bunge AL, McCabe C. Multiscale Simulation of Ternary Stratum Corneum Lipid Mixtures: Effects of Cholesterol Composition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:7496-7511. [PMID: 35671175 PMCID: PMC9309713 DOI: 10.1021/acs.langmuir.2c00471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Molecular dynamics simulations of mixtures of the ceramide nonhydroxy-sphingosine (NS), cholesterol, and a free fatty acid are performed to gain molecular-level understanding of the structure of the lipids found in the stratum corneum layer of skin. A new coarse-grained force field for cholesterol was developed using the multistate iterative Boltzmann inversion (MS-IBI) method. The coarse-grained cholesterol force field is compatible with previously developed coarse-grained force fields for ceramide NS, free fatty acids, and water and validated against atomistic simulations of these lipids using the CHARMM force field. Self-assembly simulations of multilayer structures using these coarse-grained force fields are performed, revealing that a large fraction of the ceramides adopt extended conformations, which cannot occur in the single bilayer in water structures typically studied using molecular simulation. Cholesterol fluidizes the membrane by promoting packing defects, and an increase in cholesterol content is found to reduce the bilayer thickness due to an increase in interdigitation of the C24 lipid tails, consistent with experimental observations. Using a reverse-mapping procedure, a self-assembled coarse-grained multilayer system is used to construct an equivalent structure with atomistic resolution. Simulations of this atomistic structure are found to closely agree with experimentally derived neutron scattering length density profiles. Significant interlayer hydrogen bonding is observed in the inner layers of the atomistic multilayer structure that are not found in the outer layers in contact with water or in equivalent bilayer structures. This work highlights the importance of simulating multilayer structures, as compared to the more commonly studied bilayer systems, to enable more appropriate comparisons with multilayer experimental membranes. These results also provide validation of the efficacy of the MS-IBI derived coarse-grained force fields and the framework for multiscale simulation.
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Affiliation(s)
- Parashara Shamaprasad
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Timothy C. Moore
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Donna Xia
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Christopher R. Iacovella
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
| | - Annette L. Bunge
- Department of Chemical and Biological Engineering, Colorado School of Mines, Golden, CO, USA, 80401
| | - Clare McCabe
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Multiscale Modeling and Simulation (MuMS) Center, Vanderbilt University, Nashville, TN, USA, 37235-1604
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA, 37235-1604
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12
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Beddoes CM, Gooris GS, Barlow DJ, Lawrence MJ, Dalgliesh RM, Malfois M, Demé B, Bouwstra JA. The importance of ceramide headgroup for lipid localisation in skin lipid models. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183886. [PMID: 35143742 DOI: 10.1016/j.bbamem.2022.183886] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/01/2022] [Accepted: 02/02/2022] [Indexed: 06/14/2023]
Abstract
The stratum corneum's lipid matrix is a critical for the skin's barrier function and is primarily composed of ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs). The lipids form a long periodicity phase (LPP), a unique trilayer unit cell structure. An enzyme driven pathway is implemented to synthesize these key lipids. If these enzymes are down- or upregulated as in inflammatory diseases, the final lipid composition is affected often altering the barrier function. In this study, we mimicked down regulation of enzymes involved in the synthesis of the sphingosine and CER amide bond. In a LPP lipid model, we substituted CER N-(tetracosanoyl)-sphingosine (CER NS) with either i) FFA C24 and free sphingosine, to simulate the loss of the CER amide bond, or ii) with FFA C24 and C18 to simulate the loss of the sphingosine headgroup. Our study shows the lipids in the LPP would not phase separate until at least 25% of the CER NS is substituted keeping the lateral packing and conformational ordering unaltered. Neutron diffraction studies showed that free sphingosine chains localized at the outer layers of the unit cell, while the remaining CER NS head group was concentrated in the inner headgroup layers. However, when FFA C18 was inserted, CER NS was dispersed throughout the LPP, resulting in an even distribution between the inner and outer water layers. The presented results highlight the importance of the CER NS headgroup structure and its interaction in combination with the carbon chain invariability for optimal lipid arrangement.
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Affiliation(s)
- Charlotte M Beddoes
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, University of Leiden, Leiden, the Netherlands
| | - Gert S Gooris
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, University of Leiden, Leiden, the Netherlands
| | - David J Barlow
- Division of Pharmacy and Optometry, Manchester University, Manchester, United Kingdom
| | - M Jayne Lawrence
- Division of Pharmacy and Optometry, Manchester University, Manchester, United Kingdom
| | - 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, 08290 Cerdanyola del Valles, Barcelona, Spain
| | - Bruno Demé
- Institut Laue-Langevin, Grenoble, France
| | - Joke A Bouwstra
- Division of BioTherapeutics, Leiden Academic Centre for Drug Research, University of Leiden, Leiden, the Netherlands.
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13
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Chen Y, Liao M, Ma K, Wang Z, Demé B, Penfold J, Lu JR, R P Webster J, Li P. Implications of surfactant hydrophobic chain architecture on the Surfactant-Skin lipid model interaction. J Colloid Interface Sci 2022; 608:405-415. [PMID: 34628313 DOI: 10.1016/j.jcis.2021.09.098] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/15/2021] [Accepted: 09/18/2021] [Indexed: 10/20/2022]
Abstract
Although surfactants have been widely used in skin care and other related applications, our knowledge about how surfactants interact with stratum corneum (SC) lipids remains limited. This work reports how surfactants interact with a lipid SC model by neutron diffraction and molecular dynamics (MD) simulations, focusing on examining the impact of surfactant molecular architecture. The surfactant-SC mixed membrane was constructed by an equimolar mixture of ceramide/cholesterol/fatty acids and surfactant at 1% molar ratio of total lipids. The arrangements of water and surfactant molecules in the membrane were obtained through neutron scattering length density (NSLD) profiles via contrast variation method, meanwhile, MD simulation clearly demonstrated the mechanism of hydration change in the surfactant-model SC mixed membrane. No drastic difference was detected in the repeating distance of the short periodicity phase (SPP) upon adding surfactants, however, it significantly enhanced the membrane hydration and reduced the amount of phase separated crystalline cholesterol, showing a strong dependence on surfactant chain length, branching and double bond. This work clearly demonstrates how surfactant architecture affects its interaction with the SC membrane, providing useful guidance for either choosing an existing surfactant or designing a new one for surfactant-based transdermal application.
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Affiliation(s)
- Yao Chen
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Didcot, OXON, UK OX11 0QX
| | - Mingrui Liao
- Department of Physics & Astronomy, the University of Manchester, Manchester M13 9PL, UK
| | - Kun Ma
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Didcot, OXON, UK OX11 0QX
| | - Zi Wang
- School of Science, State Key Laboratory of Heavy Oil Processing, China University of Petroleum , Qingdao 266580, China
| | - Bruno Demé
- Institut Laue-Langevin, Grenoble, France
| | - Jeff Penfold
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Didcot, OXON, UK OX11 0QX
| | - Jian R Lu
- Department of Physics & Astronomy, the University of Manchester, Manchester M13 9PL, UK
| | - John R P Webster
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Didcot, OXON, UK OX11 0QX
| | - Peixun Li
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Didcot, OXON, UK OX11 0QX.
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14
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Uche L, Gooris GS, Bouwstra JA, Beddoes CM. Increased Levels of Short-Chain Ceramides Modify the Lipid Organization and Reduce the Lipid Barrier of Skin Model Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:9478-9489. [PMID: 34319754 PMCID: PMC8389989 DOI: 10.1021/acs.langmuir.1c01295] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/09/2021] [Indexed: 06/13/2023]
Abstract
The skin barrier function is attributed to the stratum corneum (SC) intercellular lipid matrix, which is composed primarily of ceramides (CERs), free fatty acids, and cholesterol. These lipids are organized in two lamellar phases: the short and long periodicity phases (SPP and LPP), respectively. The LPP is considered important for the skin barrier function. High levels of short-chain CERs are observed in various inflammatory skin diseases and have been correlated with barrier dysfunction. In this research, we investigated how the increase in the fraction of the short-chain CER with a nonhydroxy C16 acyl chain linked to a C18 sphingosine base CER NS(C16) at the expense of the physiological chain length CER NS with a C24 acyl chain (CER NS(C24)) impacts the microstructure and barrier function of a lipid model that mimicked certain characteristics of the SC lipid organization. The permeability and lipid organization of the model membranes were compared with that of a control model without CER NS(C16). The permeability increased significantly when ≥50% of CER NS(C24) was substituted with CER NS(C16). Employing biophysical techniques, we showed that the lipid packing density reduced with an increasing proportion of CER NS(C16). Substitution of 75% of CER NS(C24) by CER NS(C16) resulted in the formation of phase-separated lipid domains and alteration of the LPP structure. Using deuterium-labeled lipids enabled simultaneous characterization of the C24 and C16 acyl chains in the lipid models, providing insight into the mechanisms underlying the reduced skin barrier function in diseased skin.
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15
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Lipid domain formation and non-lamellar structures associated with varied lysylphosphatidylglycerol analogue content in a model Staphylococcal plasma membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183571. [PMID: 33561475 DOI: 10.1016/j.bbamem.2021.183571] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/25/2021] [Accepted: 01/29/2021] [Indexed: 01/02/2023]
Abstract
Dipalmitoyl-3-aza-dehydroxy-lysylphosphatidylglycerol (DP3adLPG), is a chemically stable synthetic analogue of the bacterial lipid lysylphosphatidylglycerol (LPG), designed as a substitute for the notoriously labile native lipid in biophysical investigations. In Staphylococcus aureus, LPG is known to play a role in resistance to antibiotics by altering membrane charge properties in response to environmental stress, but little is known about how LPG influences other bilayer physicochemical properties or lateral organisation, through the formation of complexes with lipids such as phosphatidylglycerol (PG). In this study we have investigated the different phases formed by biomimetic mixtures of 3adLPG and PG in different thermotropic states, using neutron diffraction and electron microscopy. In a DPPG/DP3adLPG 70:30 mol% mixture, two distinct lamellar phases were observed below the lipid melting transition: Lβ' 1 and Lβ' 2 with respective periodicities of 82 and 62 Å. Increasing the proportion of DP3adLPG to mimic the effects of environmental stress led to the disappearance of the Lβ' 1 phase and the formation of an inverse hexagonal phase. The compositions of these different phases were identified by investigating the thermotropic properties of the two mixtures, and probing their interaction with the antimicrobial peptide magainin 2 F5W. We propose that the observed polymorphism results from the preferential formation of either triplet PG-3adLPG-PG, or paired PG-3adLPG complexes, dependent upon the mixing proportions of the two lipids. The relevance of these findings to the role native LPG in S. aureus, are discussed with respect to their influence on antibiotic resistance and lateral membrane organisation.
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16
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Ramos AP, Bouwstra JA, Lafleur M. Very Long Chain Lipids Favor the Formation of a Homogeneous Phase in Stratum Corneum Model Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:13899-13907. [PMID: 33170015 DOI: 10.1021/acs.langmuir.0c02305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The stratum corneum (SC), the outermost layer of mammal epidermis, acts as a barrier dictating the rate of absorption of exogenous molecules through the skin, as well as to prevent excessive water loss from the body. The SC consists of protein-rich corneocytes embedded into a complex lipid mixture. The lipid fraction is mainly constituted of an equimolar mixture of ceramides (Cer), free fatty acids (FFA), and cholesterol (Chol), forming a solid phase in the intracellular space; this lipid phase is supposed to play a fundamental role in the SC barrier function. An unusual characteristic of this biological membrane is that its lipids generally bear very long acyl chains, with the 24-carbon long ones being the most abundant. In this work, we used Raman microspectroscopy and infrared spectroscopy to study the influence of the acyl chain length on the lipid mixing properties in SC model membranes. Our results revealed that the combination of ceramides and FFA bearing a very long chain is required for the formation of homogeneous lipid mixtures, while lipids with shorter chains (16-carbon and 20-carbon atom long) lead to domains with micrometer dimensions. It is proposed that the biological machinery necessary for acyl chain elongation occurring at the mammalian skin level is required to inhibit lipid phase separation, a critical feature in the proper barrier functioning.
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Affiliation(s)
- Adrian Paz Ramos
- Department of Chemistry, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal QC H3C 3J7, Canada
| | - Joke A Bouwstra
- Drug Delivery Technology, Leiden Academic Centre for Drug Research, Leiden 2333 CC, The Netherlands
| | - Michel Lafleur
- Department of Chemistry, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal QC H3C 3J7, Canada
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17
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Beddoes C, Gooris GS, Foglia F, Ahmadi D, Barlow DJ, Lawrence MJ, Demé B, Bouwstra JA. Arrangement of Ceramides in the Skin: Sphingosine Chains Localize at a Single Position in Stratum Corneum Lipid Matrix Models. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:10270-10278. [PMID: 32816488 PMCID: PMC7498151 DOI: 10.1021/acs.langmuir.0c01992] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Understanding the structure of the stratum corneum (SC) is essential to understand the skin barrier process. The long periodicity phase (LPP) is a unique trilayer lamellar structure located in the SC. Adjustments in the composition of the lipid matrix, as in many skin abnormalities, can have severe effects on the lipid organization and barrier function. Although the location of individual lipid subclasses has been identified, the lipid conformation at these locations remains uncertain. Contrast variation experiments via small-angle neutron diffraction were used to investigate the conformation of ceramide (CER) N-(tetracosanoyl)-sphingosine (NS) within both simplistic and porcine mimicking LPP models. To identify the lipid conformation of the twin chain CER NS, the chains were individually deuterated, and their scattering length profiles were calculated to identify their locations in the LPP unit cell. In the repeating trilayer unit of the LPP, the acyl chain of CER NS was located in the central and outer layers, while the sphingosine chain was located exclusively in the middle of the outer layers. Thus, for the CER NS with the acyl chain in the central layer, this demonstrates an extended conformation. Electron density distribution profiles identified that the lipid structure remains consistent regardless of the lipid's lateral packing phase, this may be partially due to the anchoring of the extended CER NS. The presented results provide a more detailed insight on the internal arrangement of the LPP lipids and how they are expected to be arranged in healthy skin.
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Affiliation(s)
- Charlotte
M. Beddoes
- Division
of BioTherapeutics, Leiden Academic Centre for Drug Research, University of Leiden, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Gert S. Gooris
- Division
of BioTherapeutics, Leiden Academic Centre for Drug Research, University of Leiden, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Fabrizia Foglia
- Chemistry
Department, Christopher Ingold Laboratories, University College London, London WC1H 0AJ, United Kingdom
| | - Delaram Ahmadi
- Pharmaceutical
Science Division, King’s College
London, London WC2R 2LS, United Kingdom
| | - David J. Barlow
- Pharmaceutical
Science Division, King’s College
London, London WC2R 2LS, United Kingdom
| | - M. Jayne Lawrence
- Division
of Pharmacy and Optometry, Manchester University, Manchester M13 9PL, United Kingdom
| | - Bruno Demé
- Institute
Laue-Langevin, Grenoble 38000, France
| | - Joke A. Bouwstra
- Division
of BioTherapeutics, Leiden Academic Centre for Drug Research, University of Leiden, Einsteinweg 55, Leiden 2333 CC, The Netherlands
- . Tel: 00 31 71 527 4208. Fax: 00 31 71 527 4565
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18
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Schmitt T, Neubert RHH. State of the Art in Stratum Corneum Research. Part II: Hypothetical Stratum Corneum Lipid Matrix Models. Skin Pharmacol Physiol 2020; 33:213-230. [PMID: 32683377 DOI: 10.1159/000509019] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 05/05/2020] [Indexed: 12/31/2022]
Abstract
This review is the second part of a series which presents the state of the art in stratum corneum (SC) lipid matrix (LM) research in depth. In this part, the various hypothetical models which were developed to describe the structure and function of the SC LM as the skin's barrier will be discussed. New as well as a cumulative assortment of older results which change the view on the different models are considered to conclude how well the different models are holding up today. As a final conclusion, a model, factoring in as much of the known data as possible, is concluded, unifying the varying different models into one which can be developed further, as new results are found in the future. So far, the model is described with a single crystalline or gel-like phase with a certain amount of nanocrystallites of concentrated ceramides (CERs) and free fatty acids and more fluid nanodomains caused by a fluidizing effect of the cholesterol. These domains are dynamically resolved and reformed and do not impair the barrier function. The chain conformation is not completely clear yet; however, an equilibrium of fully extended and hairpin-folded CERs with ratios depending on the properties of each individual CER species is proposed as most likely. An overlapping middle layer as described for the tri-layer model in part I of this series would be present for both conformations. The macroscopic broad-narrow-broad layering, observed in electron micrographs, is explained by an external templating by the lipid envelope, and an internal templating by short and long lipid chains each preferentially show a homophilic association, forming thicker and thinner bilayers, respectively. The degree of influence of the very long ω-hydroxy-CERs is discussed as well.
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Affiliation(s)
- Thomas Schmitt
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Reinhard H H Neubert
- Institute of Applied Dermatopharmacy at the Martin Luther University Halle-Wittenberg (IADP), Halle/Saale, Germany, .,Institute of Pharmacy, Martin Luther University Halle-Wittenberg, Halle/Saale, Germany,
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19
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Salvador-Castell M, Demé B, Oger P, Peters J. Lipid Phase Separation Induced by the Apolar Polyisoprenoid Squalane Demonstrates Its Role in Membrane Domain Formation in Archaeal Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:7375-7382. [PMID: 32515591 DOI: 10.1021/acs.langmuir.0c00901] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Archaea synthesize methyl-branched, ether phospholipids, which confer the archaeal membrane exceptional physicochemical properties. A novel membrane organization was proposed recently to explain the thermal and high pressure tolerance of the polyextremophilic archaeon Thermococcus barophilus. According to this theoretical model, apolar molecules could populate the midplane of the bilayer and could alter the physicochemical properties of the membrane, among which is the possibility to form membrane domains. We tested this hypothesis using neutron diffraction on a model archaeal membrane composed of two archaeal diether lipids with phosphocholine and phosphoethanolamine headgroups in the presence of the apolar polyisoprenoid squalane. We show that squalane is inserted in the midplane at a maximal concentration between 5 and 10 mol % and that squalane can modify the lateral organization of the membrane and induces the coexistence of separate phases. The lateral reorganization is temperature- and squalane concentration-dependent and could be due to the release of lipid chain frustration and the induction of a negative curvature in the lipids.
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Affiliation(s)
| | - Bruno Demé
- Institut Laue Langevin, Grenoble Cedex 9 F-38042, France
| | - Phil Oger
- INSA Lyon, Université de Lyon, CNRS, UMR5240, Villeurbanne 69621, France
| | - Judith Peters
- Institut Laue Langevin, Grenoble Cedex 9 F-38042, France
- Univ. Grenoble Alpes, CNRS, LIPhy, Grenoble 38000, France
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20
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Antunes E, Cavaco-Paulo A. Stratum corneum lipid matrix with unusual packing: A molecular dynamics study. Colloids Surf B Biointerfaces 2020; 190:110928. [DOI: 10.1016/j.colsurfb.2020.110928] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 01/22/2020] [Accepted: 03/01/2020] [Indexed: 01/08/2023]
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21
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Tang NT, D. Snook R, Brown MD, Haines BA, Ridley A, Gardner P, Denbigh JL. Fatty-Acid Uptake in Prostate Cancer Cells Using Dynamic Microfluidic Raman Technology. Molecules 2020; 25:E1652. [PMID: 32260207 PMCID: PMC7180971 DOI: 10.3390/molecules25071652] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/31/2020] [Accepted: 04/01/2020] [Indexed: 12/11/2022] Open
Abstract
It is known that intake of dietary fatty acid (FA) is strongly correlated with prostate cancer progression but is highly dependent on the type of FAs. High levels of palmitic acid (PA) or arachidonic acid (AA) can stimulate the progression of cancer. In this study, a unique experimental set-up consisting of a Raman microscope, coupled with a commercial shear-flow microfluidic system is used to monitor fatty acid uptake by prostate cancer (PC-3) cells in real-time at the single cell level. Uptake of deuterated PA, deuterated AA, and the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were monitored using this new system, while complementary flow cytometry experiments using Nile red staining, were also conducted for the validation of the cellular lipid uptake. Using this novel experimental system, we show that DHA and EPA have inhibitory effects on the uptake of PA and AA by PC-3 cells.
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Affiliation(s)
- Nga-Tsing Tang
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK; (N.-T.T.); (R.D.S.)
- School of Chemical Engineering and Analytical Science, University of Manchester, Manchester M13 9PL, UK
| | - Richard D. Snook
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK; (N.-T.T.); (R.D.S.)
- School of Chemical Engineering and Analytical Science, University of Manchester, Manchester M13 9PL, UK
| | - Mick D. Brown
- Division of Cancer Sciences, University of Manchester, Manchester M20 4GJ, UK;
| | - Bryan A. Haines
- Fluxion BioSciences, 1600 Harbor Bay Parkway, #150, Alameda, CA 94502, USA;
| | - Andrew Ridley
- Labtech International Ltd., Mytogen House, 11 Browning Road, Heathfield, East Sussex TN21 8DB, UK;
| | - Peter Gardner
- Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK; (N.-T.T.); (R.D.S.)
- School of Chemical Engineering and Analytical Science, University of Manchester, Manchester M13 9PL, UK
| | - Joanna L. Denbigh
- Biomedical Research Centre, School of Science, Engineering and Environment, University of Salford, Salford M5 4WT, UK
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22
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Uche LE, Gooris GS, Bouwstra JA, Beddoes CM. Barrier Capability of Skin Lipid Models: Effect of Ceramides and Free Fatty Acid Composition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15376-15388. [PMID: 31698908 DOI: 10.1021/acs.langmuir.9b03029] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The skin is an effective barrier that prevents the influx of harmful substances from the environment and the efflux of body fluid. This barrier function is ascribed to the intercellular lipids present in the outermost layer of the skin referred to as the stratum corneum (SC). These lipids are composed mainly of ceramides (CERs), cholesterol, and free fatty acids (FFAs). Alterations in the SC lipid composition and barrier function impairment occur in several skin diseases including atopic dermatitis (AD). As the etiology of AD is multifactorial, establishing the relationship between the changes in SC lipid composition and barrier function impairment in the patients remains a challenge. Here, we employed model membrane systems to investigate the contribution of various anomalies in the SC CER and FFA composition observed in AD patients' skin to the barrier dysfunction. Using ethyl-p-aminobenzoate permeation and transepidermal water loss values as markers for barrier function, we determined that the alterations in SC lipid composition contribute to the impaired barrier function in AD patients. By the use of biophysical techniques, we established that the largest reduction in barrier capability was observed in the model with an increased fraction of short-chain FFAs, evident by the decrease in chain packing density. Modulations in the CER subclass composition impacted the lamellar organization while having a smaller effect on the barrier function. These findings provide evidence that AD therapies normalizing the FFA composition are at least as important as normalizing CER composition.
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Affiliation(s)
- Lorretta E Uche
- Division BioTherapeutics, Leiden Academic Centre for Drug Research , Leiden University , 2333 CC Leiden , Netherlands
| | - Gerrit S Gooris
- Division BioTherapeutics, Leiden Academic Centre for Drug Research , Leiden University , 2333 CC Leiden , Netherlands
| | - Joke A Bouwstra
- Division BioTherapeutics, Leiden Academic Centre for Drug Research , Leiden University , 2333 CC Leiden , Netherlands
| | - Charlotte M Beddoes
- Division BioTherapeutics, Leiden Academic Centre for Drug Research , Leiden University , 2333 CC Leiden , Netherlands
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23
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Wang E, Klauda JB. Molecular Structure of the Long Periodicity Phase in the Stratum Corneum. J Am Chem Soc 2019; 141:16930-16943. [DOI: 10.1021/jacs.9b08995] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Effect of Ceramide Tail Length on the Structure of Model Stratum Corneum Lipid Bilayers. Biophys J 2019; 114:113-125. [PMID: 29320678 DOI: 10.1016/j.bpj.2017.10.031] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 10/18/2017] [Accepted: 10/19/2017] [Indexed: 12/22/2022] Open
Abstract
Lipid bilayers composed of non-hydroxy sphingosine ceramide (CER NS), cholesterol (CHOL), and free fatty acids (FFAs), which are components of the human skin barrier, are studied via molecular dynamics simulations. Since mixtures of these lipids exist in dense gel phases with little molecular mobility at physiological conditions, care must be taken to ensure that the simulations become decorrelated from the initial conditions. Thus, we propose and validate an equilibration protocol based on simulated tempering, in which the simulation takes a random walk through temperature space, allowing the system to break out of metastable configurations and hence become decorrelated from its initial configuration. After validating the equilibration protocol, which we refer to as random-walk molecular dynamics, the effects of the lipid composition and ceramide tail length on bilayer properties are studied. Systems containing pure CER NS, CER NS + CHOL, and CER NS + CHOL + FFA, with the CER NS fatty acid tail length varied within each CER NS-CHOL-FFA composition, are simulated. The bilayer thickness is found to depend on the structure of the center of the bilayer, which arises as a result of the tail-length asymmetry between the lipids studied. The hydrogen bonding between the lipid headgroups and with water is found to change with the overall lipid composition, but is mostly independent of the CER fatty acid tail length. Subtle differences in the lateral packing of the lipid tails are also found as a function of CER tail length. Overall, these results provide insight into the experimentally observed trend of altered barrier properties in skin systems where there are more CERs with shorter tails present.
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Sochorová M, Audrlická P, Červená M, Kováčik A, Kopečná M, Opálka L, Pullmannová P, Vávrová K. Permeability and microstructure of cholesterol-depleted skin lipid membranes and human stratum corneum. J Colloid Interface Sci 2019; 535:227-238. [DOI: 10.1016/j.jcis.2018.09.104] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/27/2018] [Accepted: 09/30/2018] [Indexed: 10/28/2022]
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26
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Wang E, Klauda JB. Models for the Stratum Corneum Lipid Matrix: Effects of Ceramide Concentration, Ceramide Hydroxylation, and Free Fatty Acid Protonation. J Phys Chem B 2018; 122:11996-12008. [DOI: 10.1021/acs.jpcb.8b06188] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Beddoes CM, Gooris GS, Bouwstra JA. Preferential arrangement of lipids in the long-periodicity phase of a stratum corneum matrix model. J Lipid Res 2018; 59:2329-2338. [PMID: 30333154 DOI: 10.1194/jlr.m087106] [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: 05/18/2018] [Revised: 09/28/2018] [Indexed: 12/31/2022] Open
Abstract
The lipid matrix of the stratum corneum, the outermost skin layer, consists primarily of ceramides, cholesterol, and FFAs. These lipids form a trilayer long-periodicity phase (LPP) that is unique to this barrier. Knowledge about the LPP is essential in understanding the barrier function. Previous studies of LPP lipid models have identified the position of the major lipid classes and suggested that a large fraction of FFAs and the ceramide acyl chain are present in the central region. However, the precise arrangement, such as lipid subclass mixing (isolated or mixed) and ceramide conformation (extended or hairpin), remains unknown. Here, we deuterated FFAs and the ceramide acyl chain to study CD2 and CH2 interactions with Fourier-transform infrared spectroscopy. The ceramide and FFAs of various chain lengths were not in separate domains but had mixed together. The larger number of CD2-CD2 lipid chain interactions in the LPP than in a symmetrical bilayer structure implied that the ceramide had primarily adopted an extended conformation. Shorter FFAs were present in the central region of the LPP. This model explores the biophysical properties of the stratum corneum's LPP to improve the understanding of the barrier function of this layer.
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Affiliation(s)
- Charlotte M Beddoes
- Leiden Academic Centre for Drug Research, Division of BioTherapeutics, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands
| | - Gert S Gooris
- Leiden Academic Centre for Drug Research, Division of BioTherapeutics, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands
| | - Joke A Bouwstra
- Leiden Academic Centre for Drug Research, Division of BioTherapeutics, Gorlaeus Laboratories, University of Leiden, Leiden, The Netherlands
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Lundborg M, Narangifard A, Wennberg CL, Lindahl E, Daneholt B, Norlén L. Human skin barrier structure and function analyzed by cryo-EM and molecular dynamics simulation. J Struct Biol 2018; 203:149-161. [PMID: 29702212 DOI: 10.1016/j.jsb.2018.04.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/19/2018] [Accepted: 04/22/2018] [Indexed: 11/29/2022]
Abstract
In the present study we have analyzed the molecular structure and function of the human skin's permeability barrier using molecular dynamics simulation validated against cryo-electron microscopy data from near native skin. The skin's barrier capacity is located to an intercellular lipid structure embedding the cells of the superficial most layer of skin - the stratum corneum. According to the splayed bilayer model (Iwai et al., 2012) the lipid structure is organized as stacked bilayers of ceramides in a splayed chain conformation with cholesterol associated with the ceramide sphingoid moiety and free fatty acids associated with the ceramide fatty acid moiety. However, knowledge about the lipid structure's detailed molecular organization, and the roles of its different lipid constituents, remains circumstantial. Starting from a molecular dynamics model based on the splayed bilayer model, we have, by stepwise structural and compositional modifications, arrived at a thermodynamically stable molecular dynamics model expressing simulated electron microscopy patterns matching original cryo-electron microscopy patterns from skin extremely closely. Strikingly, the closer the individual molecular dynamics models' lipid composition was to that reported in human stratum corneum, the better was the match between the models' simulated electron microscopy patterns and the original cryo-electron microscopy patterns. Moreover, the closest-matching model's calculated water permeability and thermotropic behaviour were found compatible with that of human skin. The new model may facilitate more advanced physics-based skin permeability predictions of drugs and toxicants. The proposed procedure for molecular dynamics based analysis of cellular cryo-electron microscopy data might be applied to other biomolecular systems.
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Affiliation(s)
| | - Ali Narangifard
- ERCO Pharma AB, Science for Life Laboratory, Solna, Sweden; Department of Medicine, Solna (MedS), Karolinska Institute, Solna, Sweden
| | - Christian L Wennberg
- ERCO Pharma AB, Science for Life Laboratory, Solna, Sweden; Swedish eScience Research Center, Department of Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Erik Lindahl
- Department of Biochemistry and Biophysics, Science for Life Laboratory, Stockholm University, Stockholm, Sweden; Swedish eScience Research Center, Department of Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Bertil Daneholt
- Department of Cell and Molecular Biology (CMB), Karolinska Institute, Stockholm, Sweden
| | - Lars Norlén
- Department of Cell and Molecular Biology (CMB), Karolinska Institute, Stockholm, Sweden; Dermatology Clinic, Karolinska University Hospital, Stockholm, Sweden.
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The impact of deuteration on natural and synthetic lipids: A neutron diffraction study. Colloids Surf B Biointerfaces 2018; 168:126-133. [PMID: 29433911 DOI: 10.1016/j.colsurfb.2018.02.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 01/09/2018] [Accepted: 02/03/2018] [Indexed: 12/19/2022]
Abstract
The structural investigation of cellular membranes requires access to model systems where the molecular complexity is representative of the cellular environment and that allow for the exploitation of structural techniques. Neutron scattering, and in particular neutron diffraction can provide unique and detailed information on the structure of lipid membranes. However, deuterated samples are desirable to fully exploit this powerful method. Recently, the extraction of lipids from microorganisms grown in deuterated media was demonstrated to be both an attracting route to obtain complex lipid mixtures resembling the composition of natural membranes, and to producing deuterated molecules in a very convenient way. A full characterization of these deuterated extracts is hence pivotal for their use in building up model membrane systems. Here we report the structural characterization of lipid extracts obtained from Pichia pastoris by means of neutron diffraction measurements. In particular, we compare the structure of membranes extracted from yeast cells grown in a standard culture medium and in a corresponding deuterated culture medium. The results show that the different molecular composition of the deuterated and protiated lipid extracts induce different structural organization of the lipid membranes. In addition, we compare these membranes composed of extracted yeast lipids with stacked bilayers prepared from synthetic lipid mixtures.
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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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31
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Del Regno A, Notman R. Permeation pathways through lateral domains in model membranes of skin lipids. Phys Chem Chem Phys 2018; 20:2162-2174. [DOI: 10.1039/c7cp03258g] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Lateral organisation of skin lipids in membranes produces regions with different permeability; water permeation is favoured through cholesterol-rich regions.
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Affiliation(s)
| | - Rebecca Notman
- Department of Chemistry, University of Warwick
- Coventry
- UK
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32
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Sciacca MFM, Lolicato F, Di Mauro G, Milardi D, D'Urso L, Satriano C, Ramamoorthy A, La Rosa C. The Role of Cholesterol in Driving IAPP-Membrane Interactions. Biophys J 2017; 111:140-51. [PMID: 27410742 DOI: 10.1016/j.bpj.2016.05.050] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/15/2016] [Accepted: 05/26/2016] [Indexed: 01/01/2023] Open
Abstract
Our knowledge of the molecular events underlying type 2 diabetes mellitus-a protein conformational disease characterized by the aggregation of islet amyloid polypeptide (IAPP) in pancreatic β cells-is limited. However, amyloid-mediated membrane damage is known to play a key role in IAPP cytotoxicity, and therefore the effects of lipid composition on modulating IAPP-membrane interactions have been the focus of intense research. In particular, membrane cholesterol content varies with aging and consequently with adverse environmental factors such as diet and lifestyle, but its role in the development of the disease is controversial. In this study, we employ a combination of experimental techniques and in silico molecular simulations to shed light on the role of cholesterol in IAPP aggregation and the related membrane disruption. We show that if anionic POPC/POPS vesicles are used as model membranes, cholesterol has a negligible effect on the kinetics of IAPP fibril growth on the surface of the bilayer. In addition, cholesterol inhibits membrane damage by amyloid-induced poration on membranes, but enhances leakage through fiber growth on the membrane surface. Conversely, if 1:2 DOPC/DPPC raft-like model membranes are used, cholesterol accelerates fiber growth. Next, it enhances pore formation and suppresses fiber growth on the membrane surface, leading to leakage. Our results highlight a twofold effect of cholesterol on the amyloidogenicity of IAPP and help explain its debated role in type 2 diabetes mellitus.
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Affiliation(s)
- Michele F M Sciacca
- Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Fabio Lolicato
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy; Department of Physics, Tampere University of Technology, Tampere, Finland
| | - Giacomo Di Mauro
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy
| | - Danilo Milardi
- Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Luisa D'Urso
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy
| | - Cristina Satriano
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy
| | - Ayyalusamy Ramamoorthy
- Biophysics, University of Michigan, Ann Arbor, Michigan; Department of Chemistry, University of Michigan, Ann Arbor, Michigan; Institute for Advanced Study, Technische Universität München, Lichtenbergstrasse, Garching, Germany.
| | - Carmelo La Rosa
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy.
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33
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Permeability and microstructure of model stratum corneum lipid membranes containing ceramides with long (C16) and very long (C24) acyl chains. Biophys Chem 2017; 224:20-31. [DOI: 10.1016/j.bpc.2017.03.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 02/09/2017] [Accepted: 03/19/2017] [Indexed: 02/07/2023]
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34
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Influence of the penetration enhancer isopropyl myristate on stratum corneum lipid model membranes revealed by neutron diffraction and 2 H NMR experiments. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:745-755. [DOI: 10.1016/j.bbamem.2017.01.029] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 01/21/2017] [Accepted: 01/25/2017] [Indexed: 12/21/2022]
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35
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Sonnenberger S, Eichner A, Hauß T, Schroeter A, Neubert RH, Dobner B. Synthesis of specifically deuterated ceramide [AP]-C18 and its biophysical characterization using neutron diffraction. Chem Phys Lipids 2017; 204:15-24. [DOI: 10.1016/j.chemphyslip.2017.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/13/2017] [Accepted: 02/03/2017] [Indexed: 12/27/2022]
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36
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Biological Structures. NEUTRON SCATTERING - APPLICATIONS IN BIOLOGY, CHEMISTRY, AND MATERIALS SCIENCE 2017. [DOI: 10.1016/b978-0-12-805324-9.00001-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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37
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Eichner A, Sonnenberger S, Dobner B, Hauß T, Schroeter A, Neubert RH. Localization of methyl-branched ceramide [EOS] species within the long-periodicity phase in stratum corneum lipid model membranes: A neutron diffraction study. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:2911-2922. [DOI: 10.1016/j.bbamem.2016.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 08/25/2016] [Accepted: 09/03/2016] [Indexed: 01/03/2023]
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38
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Das C, Olmsted PD. The physics of stratum corneum lipid membranes. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:rsta.2015.0126. [PMID: 27298438 PMCID: PMC4920276 DOI: 10.1098/rsta.2015.0126] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/15/2016] [Indexed: 05/22/2023]
Abstract
The stratum corneum (SC), the outermost layer of skin, comprises rigid corneocytes (keratin-filled dead cells) in a specialized lipid matrix. The continuous lipid matrix provides the main barrier against uncontrolled water loss and invasion of external pathogens. Unlike all other biological lipid membranes (such as intracellular organelles and plasma membranes), molecules in the SC lipid matrix show small hydrophilic groups and large variability in the length of the alkyl tails and in the numbers and positions of groups that are capable of forming hydrogen bonds. Molecular simulations provide a route for systematically probing the effects of each of these differences separately. In this article, we present the results from atomistic molecular dynamics of selected lipid bilayers and multi-layers to probe the effect of these polydispersities. We address the nature of the tail packing in the gel-like phase, the hydrogen bond network among head groups, the bending moduli expected for leaflets comprising SC lipids and the conformation of very long ceramide lipids in multi-bilayer lipid assemblies.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'.
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Affiliation(s)
- Chinmay Das
- School of Mathematics, University of Leeds, Leeds LS2 9JT, UK
| | - Peter D Olmsted
- Department of Physics and Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, DC 20057, USA
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Stratum corneum lipid matrix: Location of acyl ceramide and cholesterol in the unit cell of the long periodicity phase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1926-34. [PMID: 27169629 DOI: 10.1016/j.bbamem.2016.05.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/05/2016] [Indexed: 01/04/2023]
Abstract
The extracellular lipid matrix in the skin's outermost layer, the stratum corneum, is crucial for the skin barrier. The matrix is composed of ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs) and involves two lamellar phases: the short periodicity phase (SPP) and the long periodicity phase (LPP). To understand the skin barrier thoroughly, information about the molecular arrangement in the unit cell of these lamellar phases is paramount. Previously we examined the molecular arrangement in the unit cell of the SPP. Furthermore X-ray and neutron diffraction revealed a trilayer arrangement of lipids within the unit cell of the LPP [D. Groen et al., Biophysical Journal, 97, 2242-2249, 2009]. In the present study, we used neutron diffraction to obtain more details about the location of lipid (sub)classes in the unit cell of the LPP. The diffraction pattern revealed at least 8 diffraction orders of the LPP with a repeating unit of 129.6±0.5Å. To determine the location of lipid sub(classes) in the unit cell, samples were examined with either only protiated lipids or selectively deuterated lipids. The diffraction data obtained by means of D2O/H2O contrast variation together with a gradual replacement of one particular CER, the acyl CER, by its partly deuterated counterpart, were used to construct the scattering length density profiles. The acyl chain of the acyl CER subclass is located at a position of ~21.4±0.2Å from the unit cell centre of the LPP. The position and orientation of CHOL in the LPP unit cell were determined using tail and head-group deuterated forms of the sterol. CHOL is located with its head-group positioned ~26±0.2Å from the unit cell centre. This allows the formation of a hydrogen bond with the ester group of the acyl CER located in close proximity. Based on the positions of the deuterated moieties of the acyl CER, CHOL and the previously determined location of two other lipid subclasses [E.H. Mojumdar et al., Biophysical Journal, 108, 2670-2679, 2015], a molecular model is proposed for the unit cell of the LPP. In this model CHOL is located in the two outer layers of the LPP, while CER EOS is linking the two outer layers with the central lipid layers. Finally the two other lipid subclasses are predominantly located in the central layer of the LPP.
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40
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Mojumdar EH, Gooris GS, Barlow DJ, Lawrence MJ, Deme B, Bouwstra JA. Skin lipids: localization of ceramide and fatty acid in the unit cell of the long periodicity phase. Biophys J 2016; 108:2670-9. [PMID: 26039168 DOI: 10.1016/j.bpj.2015.04.030] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 03/17/2015] [Accepted: 04/21/2015] [Indexed: 12/22/2022] Open
Abstract
The lipid matrix of the skin's stratum corneum plays a key role in the barrier function, which protects the body from desiccation. The lipids that make up this matrix consist of ceramides, cholesterol, and free fatty acids, and can form two coexisting crystalline lamellar phases: the long periodicity phase (LPP) and the short periodicity phase (SPP). To fully understand the skin barrier function, information on the molecular arrangement of the lipids in the unit cell of these lamellar phases is very desirable. To determine this arrangement in previous studies, we examined the molecular arrangement of the SPP. In this study, neutron diffraction studies were performed to obtain information on the molecular arrangement of the LPP. The diffraction pattern reveals nine diffraction orders attributed to the LPP with a repeating unit of 129.4 ± 0.5 Å. Using D2O/H2O contrast variation, the scattering length density profiles were calculated for protiated samples and samples that included either the perdeuterated acyl chain of the most abundant ceramide or the most abundant perdeuterated fatty acid. Both perdeuterated chains are predominantly located in the central part of the unit cell with substantial interdigitation of the acyl chains in the unit cell center. However, a fraction of the perdeuterated chains is also located near the border of the unit cell with their acyl chains directing toward the center. This arrangement of lipids in the LPP unit cell corresponds with the location of their lipid headgroups at the border and also inside of the unit cell at a well-defined position (±21 Å from the unit cell center), indicative of a three-layer lipid arrangement within the 129.4 ± 0.5 Å repeating unit.
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Affiliation(s)
- Enamul H Mojumdar
- Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, the Netherlands
| | - Gert S Gooris
- Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, the Netherlands
| | - David J Barlow
- Pharmaceutical Science Division, King's College London, London, United Kingdom
| | - M Jayne Lawrence
- Pharmaceutical Science Division, King's College London, London, United Kingdom
| | - Bruno Deme
- Institute Laue-Langevin, Grenoble, France
| | - Joke A Bouwstra
- Leiden Academic Centre for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Leiden, the Netherlands.
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42
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Ramos AP, Lafleur M. Chain Length of Free Fatty Acids Influences the Phase Behavior of Stratum Corneum Model Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11621-11629. [PMID: 26442576 DOI: 10.1021/acs.langmuir.5b03271] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The skin, the largest organ of the human body, forms a flexible interface between our internal and external environment that protects our organism from exogenous compounds as well as excessive water loss. The stratum corneum (SC), the outermost layer of mammal epidermis, is mainly responsible for the skin impermeability. The SC is formed by corneocytes embedded in a lipid matrix, which is mostly constituted of ceramides (Cer), free fatty acids (FFA), and cholesterol (Chol), organized in two coexisting crystalline lamellar phases. This arrangement of lipids is crucial to skin barrier function. The aim of this paper is to determine the impact of FFA chain length on the phase behavior of SC model lipid membranes using solid-state deuterium NMR and IR spectroscopy. We studied ternary mixtures of N-lignoceroyl-d-erythro-sphingosine (Cer24), cholesterol, and palmitic (FFA16) or lignoceric (FFA24) acid in an equimolar ratio. This proportion replicates the lipid composition found in the SC lipid matrix. Our studies revealed that the phase behavior of Cer24/FFA/Chol ternary mixtures is strongly affected by the length of the FFA. We found the formation of phase-separated crystalline lipid domains when using palmitic acid whereas the use of lignoceric acid results in a more homogeneous mixture. In addition, it was observed that mixtures with lignoceric acid form a gel phase, a very unusual feature for SC model mixtures.
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Affiliation(s)
- Adrian Paz Ramos
- Department of Chemistry, Center for Self-Assembled Chemical Structures (CSACS), Université de Montréal , C.P. 6128, Succursale Centre-Ville, Montréal, QC Canada H3C 3J7
| | - Michel Lafleur
- Department of Chemistry, Center for Self-Assembled Chemical Structures (CSACS), Université de Montréal , C.P. 6128, Succursale Centre-Ville, Montréal, QC Canada H3C 3J7
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Cristiglio V, Giroud B, Didier L, Demé B. D16 is back to business: more neutrons, more space, more fun. ACTA ACUST UNITED AC 2015. [DOI: 10.1080/10448632.2015.1057051] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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44
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Foglia F, Lawrence M, Barlow D. Studies of model biological and bio-mimetic membrane structure: Reflectivity vs diffraction, a critical comparison. Curr Opin Colloid Interface Sci 2015. [DOI: 10.1016/j.cocis.2015.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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45
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Mendelsohn R, Rabie E, Walters RM, Flach CR. Fatty Acid Chain Length Dependence of Phase Separation Kinetics in Stratum Corneum Models by IR Spectroscopy. J Phys Chem B 2015; 119:9740-50. [DOI: 10.1021/acs.jpcb.5b03045] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Richard Mendelsohn
- Department
of Chemistry, Newark College, Rutgers University, Newark, New Jersey 07102, United States
| | - Emann Rabie
- Department
of Chemistry, Newark College, Rutgers University, Newark, New Jersey 07102, United States
| | - Russel M. Walters
- Johnson
and Johnson
Consumer Companies, Inc., 199 Grandview
Road, Skillman, New Jersey 08558, United States
| | - Carol R. Flach
- Department
of Chemistry, Newark College, Rutgers University, Newark, New Jersey 07102, United States
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46
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Sharpe LJ, Rao G, Jones PM, Glancey E, Aleidi SM, George AM, Brown AJ, Gelissen IC. Cholesterol sensing by the ABCG1 lipid transporter: Requirement of a CRAC motif in the final transmembrane domain. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:956-64. [DOI: 10.1016/j.bbalip.2015.02.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/11/2015] [Accepted: 02/22/2015] [Indexed: 12/22/2022]
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47
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Mojumdar EH, Gooris GS, Bouwstra JA. Phase behavior of skin lipid mixtures: the effect of cholesterol on lipid organization. SOFT MATTER 2015; 11:4326-36. [PMID: 25947944 DOI: 10.1039/c4sm02786h] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The lipid matrix in the stratum corneum (SC), the upper layer of the skin, plays a critical role in the skin barrier. The matrix consists of ceramides (CERs), cholesterol (CHOL) and free fatty acids (FFAs). In human SC, these lipids form two coexisting crystalline lamellar phases with periodicities of approximately 6 and 13 nm. In the studies reported here, we investigated the effect of CHOL on lipid organization in each of these lamellar phases separately. For this purpose, we used lipid model mixtures. Our studies revealed that CHOL is imperative for the formation of each of the lamellar phases. At low CHOL levels, the formation of the lamellar phases was dramatically changed: a minimum 0.2 CHOL level in the CER/CHOL/FFA (1 : 0.2 : 1) mixture is required for the formation of each of the lamellar phases. Furthermore, CHOL enhances the formation of the highly dense orthorhombic lateral packing. The gradual increment of CHOL increases the fraction of lipids forming the very dense orthorhombic lateral packing. Therefore, these studies demonstrate that CHOL is an indispensable component of the SC lipid matrix and is of fundamental importance for appropriate dense lipid organization and thus important for the skin barrier function.
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Affiliation(s)
- E H Mojumdar
- Leiden Academic Center for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden, Einsteinweg 55, 2333 CC Leiden, The Netherlands.
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48
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Boncheva M. The physical chemistry of the stratum corneum lipids. Int J Cosmet Sci 2014; 36:505-15. [PMID: 25230344 DOI: 10.1111/ics.12162] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 09/11/2014] [Indexed: 12/20/2022]
Abstract
This article summarizes the current knowledge of the composition, self-assembly, and molecular organization of the stratum corneum (SC) lipids, reviews the evidence connecting these parameters and the barrier properties of human skin, and outlines the immediate issues in the field of SC lipid research.
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Affiliation(s)
- M Boncheva
- Corporate R&D Division, Firmenich SA, PO Box 239, Route des Jeunes 1, Geneva, CH-1211, Switzerland
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49
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Školová B, Hudská K, Pullmannová P, Kováčik A, Palát K, Roh J, Fleddermann J, Estrela-Lopis I, Vávrová K. Different Phase Behavior and Packing of Ceramides with Long (C16) and Very Long (C24) Acyls in Model Membranes: Infrared Spectroscopy Using Deuterated Lipids. J Phys Chem B 2014; 118:10460-70. [DOI: 10.1021/jp506407r] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Barbora Školová
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
- Institute
of Medical Physics and Biophysics, University of Leipzig, Härtelstrasse
16-18, 04275 Leipzig, Germany
| | - Klára Hudská
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Petra Pullmannová
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Andrej Kováčik
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Karel Palát
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Jaroslav Roh
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Jana Fleddermann
- Institute
of Medical Physics and Biophysics, University of Leipzig, Härtelstrasse
16-18, 04275 Leipzig, Germany
| | - Irina Estrela-Lopis
- Institute
of Medical Physics and Biophysics, University of Leipzig, Härtelstrasse
16-18, 04275 Leipzig, Germany
| | - Kateřina Vávrová
- Skin
Barrier Research Group, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
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50
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Mojumdar EH, Helder RWJ, Gooris GS, Bouwstra JA. Monounsaturated fatty acids reduce the barrier of stratum corneum lipid membranes by enhancing the formation of a hexagonal lateral packing. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:6534-43. [PMID: 24818519 DOI: 10.1021/la500972w] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The effectiveness of the skin barrier underlies the outer layer of the skin: the stratum corneum (SC). However, in several skin diseases this barrier is impaired. In two inflammatory skin diseases, atopic eczema and Netherton syndrome, an increased level of monounsaturated fatty acids (MUFAs) has been observed as opposed to healthy skin. In the present study, we aimed to investigate the effect of MUFAs on the lipid organization and skin lipid barrier using an in vitro model membrane system, the stratum corneum substitute (SCS), mimicking the SC lipid composition and organization. To achieve our goal, the SCS has been prepared with increasing levels of MUFAs using various chain length. Permeation studies and trans-epidermal water loss measurements show that an increment of MUFAs reduces the lipid barrier in the SCS. The increased level of unsaturation exerts its effect by reducing the packing density in the lipid organization, while the lamellar phases are not affected. Our findings indicate that increased levels of MUFAs may contribute to the impaired skin barrier in diseased skin.
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Affiliation(s)
- Enamul H Mojumdar
- Leiden Academic Center for Drug Research, Department of Drug Delivery Technology, Gorlaeus Laboratories, University of Leiden , 2333 CC Leiden, The Netherlands
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