101
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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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102
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Grond S, Radner FPW, Eichmann TO, Kolb D, Grabner GF, Wolinski H, Gruber R, Hofer P, Heier C, Schauer S, Rülicke T, Hoefler G, Schmuth M, Elias PM, Lass A, Zechner R, Haemmerle G. Skin Barrier Development Depends on CGI-58 Protein Expression during Late-Stage Keratinocyte Differentiation. J Invest Dermatol 2016; 137:403-413. [PMID: 27725204 PMCID: PMC5551682 DOI: 10.1016/j.jid.2016.09.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/02/2016] [Accepted: 09/27/2016] [Indexed: 12/12/2022]
Abstract
Adipose triglyceride lipase (ATGL) and its coactivator comparative gene identification-58 (CGI-58) are limiting in cellular triglyceride catabolism. Although ATGL deficiency is compatible with normal skin development, mice globally lacking CGI-58 die postnatally and exhibit a severe epidermal permeability barrier defect, which may originate from epidermal and/or peripheral changes in lipid and energy metabolism. Here, we show that epidermis-specific disruption of CGI-58 is sufficient to provoke a defect in the formation of a functional corneocyte lipid envelope linked to impaired ω-O-acylceramide synthesis. As a result, epidermis-specific CGI-58-deficient mice show severe skin dysfunction, arguing for a tissue autonomous cause of disease development. Defective skin permeability barrier formation in global CGI-58-deficient mice could be reversed via transgenic restoration of CGI-58 expression in differentiated but not basal keratinocytes suggesting that CGI-58 is essential for lipid metabolism in suprabasal epidermal layers. The compatibility of ATGL deficiency with normal epidermal function indicated that CGI-58 may stimulate an epidermal triglyceride lipase beyond ATGL required for the adequate provision of fatty acids as a substrate for ω-O-acylceramide synthesis. Pharmacological inhibition of ATGL enzyme activity similarly reduced triglyceride-hydrolytic activities in wild-type and CGI-58 overexpressing epidermis implicating that CGI-58 participates in ω-O-acylceramide biogenesis independent of its role as a coactivator of epidermal triglyceride catabolism.
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Affiliation(s)
- Susanne Grond
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Franz P W Radner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Thomas O Eichmann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Dagmar Kolb
- Center for Medical Research/Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Gernot F Grabner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Heimo Wolinski
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; BioTechMed-Graz, Microscopy Facility, University of Graz, Graz, Austria
| | - Robert Gruber
- Department of Dermatology, Venereology and Allergology, University of Innsbruck, Innsbruck, Austria
| | - Peter Hofer
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Christoph Heier
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Silvia Schauer
- Institute of Pathology, Medical University of Graz, Graz, Austria; Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Thomas Rülicke
- Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Gerald Hoefler
- BioTechMed-Graz, Microscopy Facility, University of Graz, Graz, Austria; Institute of Pathology, Medical University of Graz, Graz, Austria; Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Matthias Schmuth
- Department of Dermatology, Venereology and Allergology, University of Innsbruck, Innsbruck, Austria
| | - Peter M Elias
- Department of Dermatology, University of California San Francisco, San Francisco, California, USA
| | - Achim Lass
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Guenter Haemmerle
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.
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103
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CHA HWAJUN, HE CONGFEN, ZHAO HUA, DONG YINMAO, AN INSOOK, AN SUNGKWAN. Intercellular and intracellular functions of ceramides and their metabolites in skin (Review). Int J Mol Med 2016; 38:16-22. [DOI: 10.3892/ijmm.2016.2600] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 05/06/2016] [Indexed: 11/06/2022] Open
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104
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Sandhoff K. Neuronal sphingolipidoses: Membrane lipids and sphingolipid activator proteins regulate lysosomal sphingolipid catabolism. Biochimie 2016; 130:146-151. [PMID: 27157270 DOI: 10.1016/j.biochi.2016.05.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/03/2016] [Indexed: 11/16/2022]
Abstract
Glycosphingolipids and sphingolipids of cellular plasma membranes (PMs) reach luminal intra-lysosomal vesicles (LVs) for degradation mainly by pathways of endocytosis. After a sorting and maturation process (e.g. degradation of sphingomyelin (SM) and secretion of cholesterol), sphingolipids of the LVs are digested by soluble enzymes with the help of activator (lipid binding and transfer) proteins. Inherited defects of lipid-cleaving enzymes and lipid binding and transfer proteins cause manifold and fatal, often neurodegenerative diseases. The review summarizes recent findings on the regulation of sphingolipid catabolism and cholesterol secretion from the endosomal compartment by lipid modifiers, an essential stimulation by anionic membrane lipids and an inhibition of crucial steps by cholesterol and SM. Reconstitution experiments in the presence of all proteins needed, hydrolase and activator proteins, reveal an up to 10-fold increase of ganglioside catabolism just by the incorporation of anionic lipids into the ganglioside carrying membranes, whereas an additional incorporation of cholesterol inhibits GM2 catabolism substantially. It is suggested that lipid and other low molecular modifiers affect the genotype-phenotype relationship observed in patients with lysosomal diseases.
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Affiliation(s)
- Konrad Sandhoff
- University of Bonn, LIMES Institute, c/o Kekulé-Institute, Gerhard-Domagk-Str. 1, 53121 Bonn, Germany.
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105
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Li S, Ganguli-Indra G, Indra AK. Lipidomic analysis of epidermal lipids: a tool to predict progression of inflammatory skin disease in humans. Expert Rev Proteomics 2016; 13:451-6. [PMID: 27121756 PMCID: PMC4939172 DOI: 10.1080/14789450.2016.1177462] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
INTRODUCTION Lipidomics is the large-scale profiling and characterization of lipid species in a biological system using mass spectrometry. The skin barrier is mainly comprised of corneocytes and a lipid-enriched extracellular matrix. The major skin lipids are ceramides, cholesterol and free fatty acids (FFA). Lipid compositions are altered in inflammatory skin disorders with disrupted skin barrier such as atopic dermatitis (AD). AREAS COVERED Here we discuss some of the recent applications of lipidomics in human skin biology and in inflammatory skin diseases such as AD, psoriasis and Netherton syndrome. We also review applications of lipidomics in human skin equivalent and in pre-clinical animal models of skin diseases to gain insight into the pathogenesis of the skin disease. Expert commentary: Skin lipidomics analysis could be a fast, reliable and noninvasive tool to characterize the skin lipid profile and to monitor the progression of inflammatory skin diseases such as AD.
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Affiliation(s)
- Shan Li
- Department of Pharmaceutical Sciences, College of Pharmacy, OSU-OHSU
| | - Gitali Ganguli-Indra
- Department of Pharmaceutical Sciences, College of Pharmacy, OSU-OHSU
- Molecular Cell Biology Program
| | - Arup K. Indra
- Department of Pharmaceutical Sciences, College of Pharmacy, OSU-OHSU
- Molecular Cell Biology Program
- Linus Pauling Science Institute, OSU, Corvallis, OR
- Department of Dermatology, Oregon Health & Science University, OR
- Knight Cancer Institute, OHSU, OR
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106
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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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107
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Sassa T, Hirayama T, Kihara A. Enzyme Activities of the Ceramide Synthases CERS2-6 Are Regulated by Phosphorylation in the C-terminal Region. J Biol Chem 2016; 291:7477-87. [PMID: 26887952 DOI: 10.1074/jbc.m115.695858] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Indexed: 12/31/2022] Open
Abstract
Ceramide and complex sphingolipids regulate important cellular functions including cell growth, apoptosis, and signaling. Dysregulation of sphingolipid metabolism leads to pathological consequences such as sphingolipidoses and insulin resistance. Ceramides in mammals vary greatly in their acyl-chain composition: six different ceramide synthase isozymes (CERS1-6) that exhibit distinct substrate specificity and tissue distribution account for this diversity. In the present study, we demonstrated that CERS2-6 were phosphorylated at the cytoplasmic C-terminal regions. Most of the phosphorylated residues conformed to a consensus motif for phosphorylation by casein kinase 2 (CK2), and treatment of cells with the CK2-specific inhibitor CX-4945 lowered the phosphorylation levels of CERS2, -4, -5, and -6. Phosphorylation of CERS2 was especially important for its catalytic activity, acting mainly by increasing itsVmaxvalue. Phosphorylation modestly increased the catalytic activities of CERS4 and -5 and mildly increased those of CERS3 and -6. Dephosphorylation of endogenous ceramide synthases in the mouse brain led to severely reduced activity toward the Cers2 substrates C22:0/C24:0-CoAs and modestly reduced activity toward the Cers5/6 substrate C16:0-CoA. These results suggest that the phosphorylation of ceramide synthases may be a key regulatory point in the control of the distribution and levels of sphingolipids of various acyl-chain lengths.
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Affiliation(s)
- Takayuki Sassa
- From the Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
| | - Taisuke Hirayama
- From the Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
| | - Akio Kihara
- From the Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
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108
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Kováčik A, Opálka L, Šilarová M, Roh J, Vávrová K. Synthesis of 6-hydroxyceramide using ruthenium-catalyzed hydrosilylation–protodesilylation. Unexpected formation of a long periodicity lamellar phase in skin lipid membranes. RSC Adv 2016. [DOI: 10.1039/c6ra16565f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synthesis of 6-hydroxysphingosine ceramide and formation of unusual lamellar phase in model membranes of human epidermal barrier.
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Affiliation(s)
- Andrej Kováčik
- Faculty of Pharmacy in Hradec Králové
- Charles University in Prague
- 50005 Hradec Králové
- Czech Republic
| | - Lukáš Opálka
- Faculty of Pharmacy in Hradec Králové
- Charles University in Prague
- 50005 Hradec Králové
- Czech Republic
| | - Michaela Šilarová
- Faculty of Pharmacy in Hradec Králové
- Charles University in Prague
- 50005 Hradec Králové
- Czech Republic
| | - Jaroslav Roh
- Faculty of Pharmacy in Hradec Králové
- Charles University in Prague
- 50005 Hradec Králové
- Czech Republic
| | - Kateřina Vávrová
- Faculty of Pharmacy in Hradec Králové
- Charles University in Prague
- 50005 Hradec Králové
- Czech Republic
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109
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What happens in the skin? Integrating skin permeation kinetics into studies of developmental and reproductive toxicity following topical exposure. Reprod Toxicol 2015; 58:252-81. [DOI: 10.1016/j.reprotox.2015.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 08/31/2015] [Accepted: 10/07/2015] [Indexed: 02/07/2023]
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110
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Lipid mediator profile in vernix caseosa reflects skin barrier development. Sci Rep 2015; 5:15740. [PMID: 26521946 PMCID: PMC4629127 DOI: 10.1038/srep15740] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/30/2015] [Indexed: 12/16/2022] Open
Abstract
Vernix caseosa (VC) is a protective layer that covers the skin of most human newborns. This study characterized the VC lipid mediator profile, and examined its relationship to gestational period, gender of the newborn and maternal lifestyle. VC collected at birth from 156 newborns within the ALADDIN birth cohort was analyzed and 3 different groups of lipid mediators (eicosanoids and related oxylipin analogs, endocannabinoids and sphingolipids) were screened using LC-MS/MS. A total of 54 compounds were detected in VC. A number of associations between lipid mediators and the gestational period were observed, including increases in the ceramide to sphingomyelin ratio as well as the endocannabinoids anandamide and 2-arachidonoylglycerol. Gender-specific differences in lipid mediator levels were observed for all 3 lipid classes. In addition, levels of the linoleic acid oxidation products 9(10)-epoxy-12Z-octadecenoic and 12(13)-epoxy-9Z-octadecenoic acid (EpOMEs) as well as 12,13-dihydroxy-9Z-octadecenoic acid (DiHOME) were increased in VC of children from mothers with an anthroposophic lifestyle. Accordingly, VC was found to be rich in multiple classes of bioactive lipid mediators, which evidence lifestyle, gender and gestational week dependencies. Levels of lipid mediators in VC may therefore be useful as early stage non-invasive markers of the development of the skin as a protective barrier.
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111
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Opálka L, Kováčik A, Sochorová M, Roh J, Kuneš J, Lenčo J, Vávrová K. Scalable Synthesis of Human Ultralong Chain Ceramides. Org Lett 2015; 17:5456-9. [PMID: 26479675 DOI: 10.1021/acs.orglett.5b02816] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Ceramides with ultralong chains (≥30 carbons), also known as acylceramides, play a critical role in the survival of mammals on dry land. An efficient and scalable synthesis of four major classes of ultralong human skin ceramides is reported. The key approach involves the use of a succinimidyl ester that acts as a protective group, helps overcome the extremely low solubility, and simultaneously activates the fatty acid for its clean and high-yielding attachment to a sphingoid base.
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Affiliation(s)
- Lukáš Opálka
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic
| | - Andrej Kováčik
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic
| | - Michaela Sochorová
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic
| | - Jaroslav Roh
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic
| | - Jiří Kuneš
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic
| | - Juraj Lenčo
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic.,Faculty of Military Health Sciences, University of Defense , Hradec Králové 500 00, Czech Republic
| | - Kateřina Vávrová
- Faculty of Pharmacy in Hradec Králové, Charles University in Prague , Hradec Králové 500 05, Czech Republic
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112
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Essential role of the cytochrome P450 CYP4F22 in the production of acylceramide, the key lipid for skin permeability barrier formation. Proc Natl Acad Sci U S A 2015; 112:7707-12. [PMID: 26056268 DOI: 10.1073/pnas.1503491112] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A skin permeability barrier is essential for terrestrial animals, and its impairment causes several cutaneous disorders such as ichthyosis and atopic dermatitis. Although acylceramide is an important lipid for the skin permeability barrier, details of its production have yet to be determined, leaving the molecular mechanism of skin permeability barrier formation unclear. Here we identified the cytochrome P450 gene CYP4F22 (cytochrome P450, family 4, subfamily F, polypeptide 22) as the long-sought fatty acid ω-hydroxylase gene required for acylceramide production. CYP4F22 has been identified as one of the autosomal recessive congenital ichthyosis-causative genes. Ichthyosis-mutant proteins exhibited reduced enzyme activity, indicating correlation between activity and pathology. Furthermore, lipid analysis of a patient with ichthyosis showed a drastic decrease in acylceramide production. We determined that CYP4F22 was a type I membrane protein that locates in the endoplasmic reticulum (ER), suggesting that the ω-hydroxylation occurs on the cytoplasmic side of the ER. The preferred substrate of the CYP4F22 was fatty acids with a carbon chain length of 28 or more (≥C28). In conclusion, our findings demonstrate that CYP4F22 is an ultra-long-chain fatty acid ω-hydroxylase responsible for acylceramide production and provide important insights into the molecular mechanisms of skin permeability barrier formation. Furthermore, based on the results obtained here, we proposed a detailed reaction series for acylceramide production.
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113
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114
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Stahlberg S, Školová B, Madhu PK, Vogel A, Vávrová K, Huster D. Probing the role of the ceramide acyl chain length and sphingosine unsaturation in model skin barrier lipid mixtures by (2)H solid-state NMR spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:4906-4915. [PMID: 25870928 DOI: 10.1021/acs.langmuir.5b00751] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We investigated equimolar mixtures of ceramides with lignoceric acid and cholesterol as models for the human stratum corneum by differential scanning calorimetry and (2)H solid-state NMR spectroscopy. Our reference system consisted of lignoceroyl sphingosine (Cer[NS24]), which represents one of the ceramides in the human stratum corneum. Furthermore, the effect of ceramide acyl chain truncation to 16 carbons as in Cer[NS16] and the loss of the C4 trans double bond as in dihydroceramide Cer[NDS24] were studied. Fully relaxed (2)H NMR spectra were acquired for each deuterated component of each mixture separately, allowing the quantitative determination of the individual lipid phases. At skin temperature, the reference system containing Cer[NS24] is characterized by large portions of each component of the mixture in a crystalline phase, which largely restricts the permeability of the skin lipid barrier. The loss of the C4 trans double bond in Cer[NDS24] leads to the replacement of more than 25% of the crystalline phase by an isotropic phase of the dihydroceramide that shows the importance of dihydroceramide desaturation in the formation of the skin lipid barrier. The truncated Cer[NS16] is mostly found in the gel phase at skin temperature, which may explain its negative effect on the transepidermal water loss in atopic dermatitis patients. These significant alterations in the phase behavior of all lipids are further reflected at elevated temperatures. The molecular insights of our study may help us to understand the importance of the structural parameters of ceramides in healthy and compromised skin barriers.
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Affiliation(s)
- Sören Stahlberg
- †Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Barbora Školová
- †Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04107 Leipzig, Germany
- ‡Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Perunthiruthy K Madhu
- §Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
- ∥TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsingi, Hyderabad 500 075, India
| | - Alexander Vogel
- †Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Kateřina Vávrová
- ‡Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, 50005 Hradec Králové, Czech Republic
| | - Daniel Huster
- †Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, 04107 Leipzig, Germany
- §Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
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115
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Matsui T, Amagai M. Dissecting the formation, structure and barrier function of the stratum corneum. Int Immunol 2015; 27:269-80. [PMID: 25813515 DOI: 10.1093/intimm/dxv013] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 03/19/2015] [Indexed: 02/06/2023] Open
Abstract
The skin is the largest organ of the mammalian body. The outermost layer of mammalian skin, the stratum corneum (SC) of the epidermis, consists of piles of dead corneocytes that are the end-products of terminal differentiation of epidermal keratinocytes. The SC performs a crucial barrier function of epidermis. Langerhans cells, when activated, extend their dendrites through tight junctions just beneath the SC to capture external antigens. Recently, knowledge of the biology of corneocytes ('corneobiology') has progressed rapidly and many key factors that modulate its barrier function have been identified and characterized. In this review article on the SC, we summarize its evolution, formation, structure and function. Cornification is an important step of SC formation at the conversion of living epithelial cells to dead corneocytes, and consists of three major steps: formation of the intracellular keratin network, cornified envelopes and intercellular lipids. After cornification, the SC undergoes chemical reactions to form the mature SC with different functional layers. Finally, the SC is shed off at the surface ('desquamation'), mediated by a cascade of several proteases. This review will be helpful to understand our expanding knowledge of the biology of the SC, where immunity meets external antigens.
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Affiliation(s)
- Takeshi Matsui
- Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences (IMS), 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Masayuki Amagai
- Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences (IMS), 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan Department of Dermatology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
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116
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Kendall AC, Pilkington SM, Massey KA, Sassano G, Rhodes LE, Nicolaou A. Distribution of bioactive lipid mediators in human skin. J Invest Dermatol 2015; 135:1510-1520. [PMID: 25668241 DOI: 10.1038/jid.2015.41] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 12/17/2014] [Accepted: 01/23/2015] [Indexed: 12/30/2022]
Abstract
The skin produces bioactive lipids that participate in physiological and pathological states, including homeostasis, induction, propagation, and resolution of inflammation. However, comprehension of the cutaneous lipid complement, and contribution to differing roles of the epidermal and dermal compartments, remains incomplete. We assessed the profiles of eicosanoids, endocannabinoids, N-acyl ethanolamides, and sphingolipids, in human dermis, epidermis, and suction blister fluid. We identified 18 prostanoids, 12 hydroxy-fatty acids, 9 endocannabinoids and N-acyl ethanolamides, and 21 non-hydroxylated ceramides and sphingoid bases, several demonstrating significantly different expression in the tissues assayed. The array of dermal and epidermal fatty acids was reflected in the lipid mediators produced, whereas similarities between lipid profiles in blister fluid and epidermis indicated a primarily epidermal origin of suction blister fluid. Supplementation with omega-3 fatty acids ex vivo showed that their action is mediated through perturbation of existing species and formation of other anti-inflammatory lipids. These findings demonstrate the diversity of lipid mediators involved in maintaining tissue homeostasis in resting skin and hint at their contribution to signaling, cross-support, and functions of different skin compartments. Profiling lipid mediators in biopsies and suction blister fluid can support studies investigating cutaneous inflammatory responses, dietary manipulation, and skin diseases lacking biomarkers and therapeutic targets.
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Affiliation(s)
- Alexandra C Kendall
- Faculty of Medical and Human Sciences, Manchester Pharmacy School, The University of Manchester, Manchester, UK
| | - Suzanne M Pilkington
- Dermatology Centre, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
| | - Karen A Massey
- School of Pharmacy and Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, UK
| | - Gary Sassano
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, UK
| | - Lesley E Rhodes
- Dermatology Centre, Institute of Inflammation and Repair, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
| | - Anna Nicolaou
- Faculty of Medical and Human Sciences, Manchester Pharmacy School, The University of Manchester, Manchester, UK.
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117
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Lin MH, Miner JH. Fatty acid transport protein 1 can compensate for fatty acid transport protein 4 in the developing mouse epidermis. J Invest Dermatol 2014; 135:462-470. [PMID: 25184958 PMCID: PMC4289464 DOI: 10.1038/jid.2014.378] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/15/2014] [Accepted: 07/16/2014] [Indexed: 11/18/2022]
Abstract
Fatty acid transport protein (FATP) 4 is one of a family of six FATPs that facilitate long- and very long-chain fatty acid uptake. Mice lacking FATP4 are born with tight, thick skin and a defective barrier; they die neonatally due to dehydration and restricted movements. Mutations in SLC27A4, the gene encoding FATP4, cause ichthyosis prematurity syndrome (IPS), characterized by premature birth, respiratory distress, and edematous skin with severe ichthyotic scaling. Symptoms of surviving patients become mild, though atopic manifestations are common. We previously showed that suprabasal keratinocyte expression of a Fatp4 transgene in Fatp4 mutant skin rescues the lethality and ameliorates the skin phenotype. Here we tested the hypothesis that FATP1, the closest FATP4 homolog, can compensate for the lack of FATP4 in our mouse model of IPS, as it might do postnatally in IPS patients. Transgenic expression of FATP1 in suprabasal keratinocytes rescued the phenotype of Fatp4 mutants, and FATP1 sorted to the same intracellular organelles as endogenous FATP4. Thus, FATP1 and FATP4 likely have overlapping substrate specificities, enzymatic activities, and biological functions. These results suggest that increasing expression of FATP1 in suprabasal keratinocytes could normalize the skin of IPS patients and perhaps prevent the atopic manifestations.
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Affiliation(s)
- Meei-Hua Lin
- Renal Division, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jeffrey H Miner
- Renal Division, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA.
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118
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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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119
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Elias PM, Wakefield JS. Mechanisms of abnormal lamellar body secretion and the dysfunctional skin barrier in patients with atopic dermatitis. J Allergy Clin Immunol 2014; 134:781-791.e1. [PMID: 25131691 DOI: 10.1016/j.jaci.2014.05.048] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 04/29/2014] [Accepted: 05/07/2014] [Indexed: 12/22/2022]
Abstract
I review how diverse inherited and acquired abnormalities in epidermal structural and enzymatic proteins converge to produce defective permeability barrier function and antimicrobial defense in patients with atopic dermatitis (AD). Although best known are mutations in filaggrin (FLG), mutations in other member of the fused S-100 family of proteins (ie, hornerin [hrn] and filaggrin 2 [flg-2]); the cornified envelope precursor (ie, SPRR3); mattrin, which is encoded by TMEM79 and regulates the assembly of lamellar bodies; SPINK5, which encodes the serine protease inhibitor lymphoepithelial Kazal-type trypsin inhibitor type 1; and the fatty acid transporter fatty acid transport protein 4 have all been linked to AD. Yet these abnormalities often only predispose to AD; additional acquired stressors that further compromise barrier function, such as psychological stress, low ambient humidity, or high-pH surfactants, often are required to trigger disease. T(H)2 cytokines can also compromise barrier function by downregulating expression of multiple epidermal structural proteins, lipid synthetic enzymes, and antimicrobial peptides. All of these inherited and acquired abnormalities converge on the lamellar body secretory system, producing abnormalities in lipid composition, secretion, and/or extracellular lamellar membrane organization, as well as antimicrobial defense. Finally, I briefly review therapeutic options that address this new pathogenic paradigm.
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Affiliation(s)
- Peter M Elias
- Dermatology Service, Veterans Affairs Medical Center, and the Department of Dermatology, University of California, San Francisco, Calif.
| | - Joan S Wakefield
- Dermatology Service, Veterans Affairs Medical Center, and the Department of Dermatology, University of California, San Francisco, Calif
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120
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Kováčik A, Roh J, Vávrová K. The chemistry and biology of 6-hydroxyceramide, the youngest member of the human sphingolipid family. Chembiochem 2014; 15:1555-62. [PMID: 24990520 DOI: 10.1002/cbic.201402153] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Indexed: 11/08/2022]
Abstract
Sphingolipids are crucial for the life of the cell. In land-dwelling mammals, they are equally important outside the cell-in the extracellular space of the skin barrier-because they prevent loss of water. Although a large body of research has elucidated many of the functions of sphingolipids, their extensive structural diversity remains intriguing. A new class of sphingolipids based on 6-hydroxylated sphingosine has recently been identified in human skin. Abnormal levels of these 6-hydroxylated ceramides have repeatedly been observed in atopic dermatitis; however, neither the biosynthesis nor the roles of these unique ceramide subclasses have been established in the human body. In this Minireview, we summarize the current knowledge of 6-hydroxyceramides, including their discovery, structure, stereochemistry, occurrence in healthy and diseased human epidermis, and synthetic approaches to 6-hydroxysphingosine and related ceramides.
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Affiliation(s)
- Andrej Kováčik
- Skin Barrier Research Group, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Heyrovského 1203, 50005 Hradec Králové (Czech Republic)
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121
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Sassa T, Kihara A. Metabolism of very long-chain Fatty acids: genes and pathophysiology. Biomol Ther (Seoul) 2014; 22:83-92. [PMID: 24753812 PMCID: PMC3975470 DOI: 10.4062/biomolther.2014.017] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/03/2014] [Indexed: 01/19/2023] Open
Abstract
Fatty acids (FAs) are highly diverse in terms of carbon (C) chain-length and number of double bonds. FAs with C>20 are called very long-chain fatty acids (VLCFAs). VLCFAs are found not only as constituents of cellular lipids such as sphingolipids and glycerophospholipids but also as precursors of lipid mediators. Our understanding on the function of VLCFAs is growing in parallel with the identification of enzymes involved in VLCFA synthesis or degradation. A variety of inherited diseases, such as ichthyosis, macular degeneration, myopathy, mental retardation, and demyelination, are caused by mutations in the genes encoding VLCFA metabolizing enzymes. In this review, we describe mammalian VLCFAs by highlighting their tissue distribution and metabolic pathways, and we discuss responsible genes and enzymes with reference to their roles in pathophysiology.
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Affiliation(s)
- Takayuki Sassa
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
| | - Akio Kihara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
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122
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Kim J, Kim YS, Cho Y. WITHDRAWN: Lithospermum erythrorhizon extract improves the hydration, sebum, and ceramide content of healthy skin: results from a randomized, placebo-controlled, double-blind study. Nutr Res 2014. [DOI: 10.1016/j.nutres.2014.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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123
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Pullmannová P, Staňková K, Pospíšilová M, Skolová B, Zbytovská J, Vávrová K. Effects of sphingomyelin/ceramide ratio on the permeability and microstructure of model stratum corneum lipid membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2115-26. [PMID: 24824073 DOI: 10.1016/j.bbamem.2014.05.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 04/10/2014] [Accepted: 05/03/2014] [Indexed: 11/27/2022]
Abstract
The conversion of sphingomyelin (SM) to a ceramide (Cer) by acid sphingomyelinase (aSMase) is an important event in skin barrier development. A deficiency in aSMase in diseases such as Niemann-Pick disease and atopic dermatitis coincides with impaired skin barrier recovery after disruption. We studied how an increased SM/Cer ratio influences the barrier function and microstructure of model stratum corneum (SC) lipid membranes. In the membranes composed of isolated human SC Cer (hCer)/cholesterol/free fatty acids/cholesteryl sulfate, partial or full replacement of hCer by SM increased water loss. Partial replacement of 25% and 50% of hCer by SM also increased the membrane permeability to theophylline and alternating electric current, while a higher SM content either did not alter or even decreased the membrane permeability. In contrast, in a simple membrane model with only one type of Cer (nonhydroxyacyl sphingosine, CerNS), an increased SM/Cer ratio provided a similar or better barrier against the permeation of various markers. X-ray powder diffraction revealed that the replacement of hCer by SM interferes with the formation of the long periodicity lamellar phase with a repeat distance of d=12.7nm. Our results suggest that SM-to-Cer processing in the human epidermis is essential for preventing excessive water loss, while the permeability barrier to exogenous compounds is less sensitive to the presence of sphingomyelin.
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Affiliation(s)
- Petra Pullmannová
- Skin Barrier Research Group, Charles University in Prague, Faculty of Pharmacy, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Klára Staňková
- Skin Barrier Research Group, Charles University in Prague, Faculty of Pharmacy, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Markéta Pospíšilová
- Skin Barrier Research Group, Charles University in Prague, Faculty of Pharmacy, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Barbora Skolová
- Skin Barrier Research Group, Charles University in Prague, Faculty of Pharmacy, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
| | - Jarmila Zbytovská
- Institute of Chemical Technology Prague, Technická 5, 166 28 Prague, Czech Republic
| | - Kateřina Vávrová
- Skin Barrier Research Group, Charles University in Prague, Faculty of Pharmacy, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic
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124
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Feingold KR, Elias PM. Role of lipids in the formation and maintenance of the cutaneous permeability barrier. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:280-94. [PMID: 24262790 DOI: 10.1016/j.bbalip.2013.11.007] [Citation(s) in RCA: 256] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 11/01/2013] [Accepted: 11/10/2013] [Indexed: 12/18/2022]
Abstract
The major function of the skin is to form a barrier between the internal milieu and the hostile external environment. A permeability barrier that prevents the loss of water and electrolytes is essential for life on land. The permeability barrier is mediated primarily by lipid enriched lamellar membranes that are localized to the extracellular spaces of the stratum corneum. These lipid enriched membranes have a unique structure and contain approximately 50% ceramides, 25% cholesterol, and 15% free fatty acids with very little phospholipid. Lamellar bodies, which are formed during the differentiation of keratinocytes, play a key role in delivering the lipids from the stratum granulosum cells into the extracellular spaces of the stratum corneum. Lamellar bodies contain predominantly glucosylceramides, phospholipids, and cholesterol and following the exocytosis of lamellar lipids into the extracellular space of the stratum corneum these precursor lipids are converted by beta glucocerebrosidase and phospholipases into the ceramides and fatty acids, which comprise the lamellar membranes. The lipids required for lamellar body formation are derived from de novo synthesis by keratinocytes and from extra-cutaneous sources. The lipid synthetic pathways and the regulation of these pathways are described in this review. In addition, the pathways for the uptake of extra-cutaneous lipids into keratinocytes are discussed. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.
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Affiliation(s)
- Kenneth R Feingold
- Metabolism Section, Medicine Service and Dermatology Service, Department of Veterans Affairs Medical Center, University of California San Francisco, San Francisco, CA 94121, USA.
| | - Peter M Elias
- Metabolism Section, Medicine Service and Dermatology Service, Department of Veterans Affairs Medical Center, University of California San Francisco, San Francisco, CA 94121, USA
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125
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Kota V, Hama H. 2'-Hydroxy ceramide in membrane homeostasis and cell signaling. Adv Biol Regul 2013; 54:223-30. [PMID: 24139861 DOI: 10.1016/j.jbior.2013.09.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 09/15/2013] [Indexed: 01/25/2023]
Abstract
Ceramide is a precursor of complex sphingolipids and also plays important roles in cell signaling. With the advances in lipid analytical technologies, the structural diversity of ceramide species have become evident, and the complexity of cellular metabolism and function associated with distinct ceramide species is beginning to be revealed. One of the common structural variations of ceramide is 2'-hydroxylation of the N-acyl chain. Fatty acid 2-hydroxylase (FA2H) is one of the enzymes that introduce the hydroxyl group during de novo synthesis of ceramide. FA2H is essential for the normal functioning of the nervous system, as evidenced by demyelinating disorder associated with FA2H mutations in humans and mice. Studies of Fa2h mutant mice indicate that lack of 2'-hydroxy galactosylceramide in the myelin membrane results in loss of long-term stability of myelin and eventual demyelination. FA2H also regulates differentiation of various cell types (epidermal keratinocytes, schwannoma cells, adipocytes). When provided exogenously, ceramide induces apoptosis in many cell types. Interestingly, the effective concentration of 2'-hydroxy ceramide that induces apoptosis is significantly lower compared to non-hydroxy ceramide, and cells die much more rapidly, suggesting that 2'-hydroxy ceramide can mediate proapoptotic signaling distinct from non-hydroxy ceramide. Collectively, current evidence clearly shows that 2'-hydroxy ceramide and 2'-hydroxy complex sphingolipids have unique functions in membrane homeostasis and cell signaling that could not be substituted by non-hydroxy counterparts.
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Affiliation(s)
- Venkatesh Kota
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425, USA
| | - Hiroko Hama
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425, USA.
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126
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Rabionet M, Bayerle A, Marsching C, Jennemann R, Gröne HJ, Yildiz Y, Wachten D, Shaw W, Shayman JA, Sandhoff R. 1-O-acylceramides are natural components of human and mouse epidermis. J Lipid Res 2013; 54:3312-21. [PMID: 24078707 DOI: 10.1194/jlr.m040097] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The lipid-rich stratum corneum functions as a barrier against pathogens and desiccation inter alia by an unbroken meshwork of extracellular lipid lamellae. These lamellae are composed of cholesterol, fatty acids, and ceramides (Cers) in an equimolar ratio. The huge class of skin Cers consists of three groups: group I, "classical" long and very long chain Cers; group II, ultra-long chain Cers; and group III, ω-esterified ultra-long chain Cers, which are esterified either with linoleic acid or with cornified envelope proteins and are required for the water permeability barrier. Here, we describe 1-O-acylceramides as a new class of epidermal Cers in humans and mice. These Cers contain, in both the N- and 1-O-position, long to very long acyl chains. They derive from the group I of classical Cers and make up 5% of all esterified Cers. Considering their chemical structure and hydrophobicity, we presume 1-O-acylceramides to contribute to the water barrier homeostasis. Biosynthesis of 1-O-acylceramides is not dependent on lysosomal phospholipase A2. However, glucosylceramide synthase deficiency was followed by a 7-fold increase of 1-O-acylceramides, which then contributed 30% to all esterified Cers. Furthermore, loss of neutral glucosylceramidase resulted in decreased levels of a 1-O-acylceramide subgroup. Therefore, we propose 1-O-acylceramides to be synthesized at endoplasmic reticulum-related sites.
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Affiliation(s)
- Mariona Rabionet
- Lipid Pathobiochemistry Group within, German Cancer Research Center (DKFZ), Heidelberg, Germany
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