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Nicolaou A, Kendall AC. Bioactive lipids in the skin barrier mediate its functionality in health and disease. Pharmacol Ther 2024:108681. [PMID: 38897295 DOI: 10.1016/j.pharmthera.2024.108681] [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: 02/05/2024] [Revised: 05/11/2024] [Accepted: 06/13/2024] [Indexed: 06/21/2024]
Abstract
Our skin protects us from external threats including ultraviolet radiation, pathogens and chemicals, and prevents excessive trans-epidermal water loss. These varied activities are reliant on a vast array of lipids, many of which are unique to skin, and that support physical, microbiological and immunological barriers. The cutaneous physical barrier is dependent on a specific lipid matrix that surrounds terminally-differentiated keratinocytes in the stratum corneum. Sebum- and keratinocyte-derived lipids cover the skin's surface and support and regulate the skin microbiota. Meanwhile, lipids signal between resident and infiltrating cutaneous immune cells, driving inflammation and its resolution in response to pathogens and other threats. Lipids of particular importance include ceramides, which are crucial for stratum corneum lipid matrix formation and therefore physical barrier functionality, fatty acids, which contribute to the acidic pH of the skin surface and regulate the microbiota, as well as the stratum corneum lipid matrix, and bioactive metabolites of these fatty acids, involved in cell signalling, inflammation, and numerous other cutaneous processes. These diverse and complex lipids maintain homeostasis in healthy skin, and are implicated in many cutaneous diseases, as well as unrelated systemic conditions with skin manifestations, and processes such as ageing. Lipids also contribute to the gut-skin axis, signalling between the two barrier sites. Therefore, skin lipids provide a valuable resource for exploration of healthy cutaneous processes, local and systemic disease development and progression, and accessible biomarker discovery for systemic disease, as well as an opportunity to fully understand the relationship between the host and the skin microbiota. Investigation of skin lipids could provide diagnostic and prognostic biomarkers, and help identify new targets for interventions. Development and improvement of existing in vitro and in silico approaches to explore the cutaneous lipidome, as well as advances in skin lipidomics technologies, will facilitate ongoing progress in skin lipid research.
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Affiliation(s)
- Anna Nicolaou
- Laboratory for Lipidomics and Lipid Biology, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9NT, UK; Lydia Becker Institute of Immunology and Inflammation; Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9NT, UK.
| | - Alexandra C Kendall
- Laboratory for Lipidomics and Lipid Biology, Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9NT, UK
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Raghav RS, Verma S, Monika. A Comprehensive Review on Potential Chemical and Herbal Permeation Enhancers Used in Transdermal Drug Delivery Systems. RECENT ADVANCES IN DRUG DELIVERY AND FORMULATION 2024; 18:21-34. [PMID: 38258784 DOI: 10.2174/0126673878272043240114123908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/09/2023] [Accepted: 10/16/2023] [Indexed: 01/24/2024]
Abstract
Using skin patches to deliver drugs is dependable and doesn't have the same issues as permeation enhancers, which help drugs get through the skin but struggle because of the skin's natural barrier. Strategies are required to increase topical bioavailability to enhance drug absorption. Natural compounds offer a promising solution by temporarily reducing skin barrier resistance and improving drug absorption. Natural substances allow a wider variety of medications to be distributed through the stratum corneum, offering a dependable approach to enhancing transdermal drug delivery. Natural substances have distinct advantages as permeability enhancers. They are pharmacologically effective and safe, inactive, non-allergenic, and non-irritating. These characteristics ensure their suitability for use without causing adverse effects. Natural compounds are readily available and well tolerated by the body. Studies investigating the structure-activity relationship of natural chemicals have demonstrated significant enhancer effects. By understanding the connection between chemical composition and enhancer activity, researchers can identify effective natural compounds for improving drug penetration. In conclusion, current research focuses on utilizing natural compounds as permeability enhancers in transdermal therapy systems. These substances offer safety, non-toxicity, pharmacological inactivity, and non-irritation. Through structure-activity relationship investigations, promising advancements have been made in enhancing drug delivery. Using natural compounds holds enormous potential for improving the penetration of trans-dermally delivered medications.
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Affiliation(s)
- Rajat Singh Raghav
- Department of Pharmacy, Faculty of Pharmaceutics, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, 201306, India
| | - Sushma Verma
- Department of Pharmacy, Faculty of Pharmaceutics, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, 201306, India
| | - Monika
- Department of Pharmacy, Faculty of Pharmaceutics, Noida Institute of Engineering and Technology (Pharmacy Institute), Greater Noida, 201306, India
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Jojima K, Kihara A. Metabolism of sphingadiene and characterization of the sphingadiene-producing enzyme FADS3. Biochim Biophys Acta Mol Cell Biol Lipids 2023; 1868:159335. [PMID: 37209771 DOI: 10.1016/j.bbalip.2023.159335] [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: 02/17/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/22/2023]
Abstract
Of the long-chain bases (LCBs) that comprise the ceramides (CERs) present in mammals, only 4,14-sphingadiene (sphingadiene; SPD) has a cis double bond (at C14). Because of this unique structure, the metabolism of SPD may differ from that of other LCBs, but whether this is the case remains unclear. FADS3 is responsible for introducing the cis double bond in SPD. However, the substrate specificity of FADS3 and cofactors involved in the FADS3-catalyzed reaction are also unknown. In the present study, a cell-based assay using a ceramide synthase inhibitor and an in vitro experiment showed that FADS3 is active toward sphingosine (SPH)-containing CERs (SPH-CERs) but not toward free SPH. FADS3 exhibits specificity with respect to the chain length of the SPH moiety of SPH-CERs (active toward C16-20), but not that of the fatty acid moiety. Furthermore, FADS3 is active toward straight-chain and isobranched-chain SPH-containing CERs but not toward anteiso-branched forms. In addition to SPH-CERs, FADS3 also shows activity toward dihydrosphingosine-containing CERs, but this activity is approximately half of that toward SPH-CERs. It uses either NADH or NADPH as an electron donor, and the electron transfer is facilitated by cytochrome b5. The metabolic flow of SPD to sphingomyelin is predominant over that to glycosphingolipids. In the metabolic pathway from SPD to fatty acids, the chain length of the SPD is reduced by two carbons and the trans double bond at C4 is saturated. This study thus elucidates the enzymatic properties of FADS3 and the metabolism of SPD.
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Affiliation(s)
- Keisuke Jojima
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Akio Kihara
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
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Nicolaou A, Kendall AC. Current insights into skin lipids and their roles in cutaneous health and disease. Curr Opin Clin Nutr Metab Care 2023; 26:83-90. [PMID: 36574279 DOI: 10.1097/mco.0000000000000902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE OF REVIEW The unique and complex array of cutaneous lipids include essential components of the skin structure and signalling molecules mediating homeostasis and inflammation. Understanding skin lipid biology and metabolism can support our comprehension of health and disease, including systemic conditions with cutaneous involvement. RECENT FINDINGS Lipids found on the skin surface, produced by both the host and resident microbes, maintain and regulate the skin microbiome and the epidermal barrier, whilst altered contributions from either source can be detrimental to skin health. The unique lipid composition of the epidermal barrier is essential for its function, and recent studies have expanded our understanding of epidermal ceramide production. This has been supported by improved models available for skin research, including organotypic skin models enabling in-vitro production of complex acylceramides for the first time, and model systems facilitating in-silico exploration of the lipid profile changes observed in clinical samples. Studies have revealed further involvement of lipid mediators such as eicosanoids in cutaneous inflammation, as well as immune regulation in both healthy and diseased skin. SUMMARY Skin lipids offer exciting opportunities as therapeutic targets for many conditions, whether through topical interventions or nutritional supplementation.
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Affiliation(s)
- Anna Nicolaou
- Laboratory for Lipidomics and Lipid Biology, Division of Pharmacy and Optometry, School of Health Sciences
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Alexandra C Kendall
- Laboratory for Lipidomics and Lipid Biology, Division of Pharmacy and Optometry, School of Health Sciences
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Tamura Y, Sassa T, Nishizawa T, Kihara A. Incomplete Elongation of Ultra-long-chain Polyunsaturated Acyl-CoAs by the Fatty Acid Elongase ELOVL4 in Spinocerebellar Ataxia Type 34. Mol Cell Biol 2023; 43:1-17. [PMID: 36748939 PMCID: PMC9980445 DOI: 10.1080/10985549.2023.2169563] [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: 09/12/2022] [Revised: 11/24/2022] [Accepted: 01/11/2023] [Indexed: 02/08/2023] Open
Abstract
Spinocerebellar ataxias (SCAs) are autosomal dominant diseases characterized by cerebellar atrophy and ataxia. The SCA subtype SCA34 is caused by specific mutations in the gene ELOVL4, which encodes a fatty acid (FA) elongase that synthesizes ultra-long-chain (ULC; ≥C26) FAs. However, the pathogenesis and molecular mechanism that confers dominant inheritance remains unknown. Here, a cell-based assay demonstrated that each of the five known SCA34 mutants produced shorter ULC polyunsaturated FA-containing phosphatidylcholines (ULC-PCs) than wild-type protein, in the following order of severity: Q180P and T233M > W246G > I171T and L168F. Next, we generated knock-in mouse embryonic stem cells that contained heterozygous Q180P, heterozygous W246G, or homozygous W246G mutations. Neuronal differentiation-dependent production of ULC-PCs was reduced in heterozygous Q180P and homozygous W246G cells relative to control cells, and we observed shortening of the FA moiety in all mutant cells. This FA shortening was consistent with our prediction that amino acid residues substituted by SCA34 mutations are located in the transmembrane helices that interact with the ω-end region of the FA moiety of the substrate acyl-CoA. Hence, reduced levels and shortening of ULC-PCs in neurons may cause SCA34, and incomplete elongation of ULC polyunsaturated acyl-CoAs by mutated ELOVL4 may induce dominant inheritance.
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Affiliation(s)
- Yuka Tamura
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Takayuki Sassa
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Takumi Nishizawa
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Akio Kihara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
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Murashkin NN, Avetisyan KO, Ivanov RA, Makarova SG. Congenital Ichthyosis: Clinical and Genetic Characteristics of the Disease. CURRENT PEDIATRICS 2022. [DOI: 10.15690/vsp.v21i5.2459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Congenital ichthyosis is a group (almost 100 clinical variants) of rare genetic skin diseases caused by pathogenic changes in more than 50 genes. Clinical features of ichthyosis, regardless of its genotype, are dry skin, peeling, hyperkeratosis frequently accompanied with erythroderma. These patients have extremely low quality of life due to changes in appearance, discomfort due to itching and functional limitations (pain during walking, impaired hands motor skills and functions due to hyperkeratosis foci in functionally relevant areas), as well as impaired functions of various organs and systems in syndromic forms of disease. Patients need daily skin care and systemic medications. By now, there is no definitive treatment for ichthyosis. Diagnostic difficulties in determining the clinical forms of congenital ichthyosis are associated with their clinical heterogeneity and with similarity in external manifestations. Difficulties in differential diagnosis with other dermatoses are particularly crucial in case of syndromic forms of disease. This review presents the modern classification of ichthyoses, provides data on disease clinical and genetic variants, diagnostic algorithms, treatment methods for patients with this severe disease.
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Affiliation(s)
- N. N. Murashkin
- National Medical Research Center of Children’s Health; Sechenov First Moscow State Medical University; Central State Medical Academy of Department of Presidential Affairs
| | | | - R. A. Ivanov
- National Medical Research Center of Children’s Health; Central State Medical Academy of Department of Presidential Affairs
| | - S. G. Makarova
- National Medical Research Center of Children’s Health; Pirogov Russian National Research Medical University
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Arai A, Takeichi T, Wakamoto H, Sassa T, Ito Y, Murase Y, Ogi T, Akiyama M, Kihara A. Ceramide profiling of stratum corneum in Sjögren-Larsson syndrome. J Dermatol Sci 2022; 107:114-122. [PMID: 35973883 DOI: 10.1016/j.jdermsci.2022.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/20/2022] [Accepted: 08/07/2022] [Indexed: 12/22/2022]
Abstract
BACKGROUND Sjögren-Larsson syndrome (SLS) is a neurocutaneous disorder whose causative gene is the fatty aldehyde dehydrogenase ALDH3A2 and of which ichthyosis is the major skin symptom. The stratum corneum contains a variety of ceramides, among which ω-O-acylceramides (acylceramides) and protein-bound ceramides are essential for skin permeability barrier formation. OBJECTIVES To determine the ceramide classes/species responsible for SLS pathogenesis and the enzymes that are impaired in SLS. METHODS Genomic DNA was collected from peripheral blood samples from an SLS patient and her parents, and whole-genome sequencing and Sanger sequencing were performed. Lipids were extracted from stratum corneum samples from the SLS patient and healthy volunteers and subjected to ceramide profiling via liquid chromatography coupled with tandem mass spectrometry. RESULTS A duplication (c.55_130dup) and a missense mutation (p.Lys447Glu) were found in the patient's ALDH3A2 gene. The patient had reduced levels of all acylceramide classes, with total acylceramide levels at 25 % of healthy controls. Reductions were also observed for several nonacylated ceramides: ceramides with phytosphingosine or 6-hydroxysphingosine in the long-chain base moiety were reduced to 24 % and 41 % of control levels, respectively, and ceramides with an α-hydroxy fatty acid as the fatty acid moiety were reduced to 29 %. The fatty acid moiety was shortened in many nonacylated ceramide classes. CONCLUSION These results suggest that reduced acylceramide levels are a primary cause of the ichthyosis symptoms of SLS, but reductions in other ceramide classes may also be involved.
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Affiliation(s)
- Ayami Arai
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Takuya Takeichi
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroyuki Wakamoto
- Department of Pediatrics, Ehime Rehabilitation Center for Children, Ehime, Japan
| | - Takayuki Sassa
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Yasutoshi Ito
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuya Murase
- Department of Pediatrics, Ehime Rehabilitation Center for Children, Ehime, Japan
| | - Tomoo Ogi
- Department of Genetics, Research Institute of Environmental Medicine (RIeM), Nagoya University, Nagoya, Japan; Department of Human Genetics and Molecular Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masashi Akiyama
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akio Kihara
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.
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Gao X, Lin L, Hu A, Zhao H, Kang L, Wang X, Yuan C, Yang P, Shen H. Shotgun lipidomics combined targeted MRM reveals sphingolipid signatures of coronary artery disease. Talanta 2022; 245:123475. [DOI: 10.1016/j.talanta.2022.123475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/07/2022] [Accepted: 04/09/2022] [Indexed: 11/16/2022]
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Takahashi T, Mercan S, Sassa T, Akçapınar GB, Yararbaş K, Süsgün S, İşeri SAU, Kihara A, Akçakaya NH. Hypomyelinating spastic dyskinesia and ichthyosis caused by a homozygous splice site mutation leading to exon skipping in ELOVL1. Brain Dev 2022; 44:391-400. [PMID: 35379526 DOI: 10.1016/j.braindev.2022.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 02/14/2022] [Accepted: 03/14/2022] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Next generation sequencing technologies allow detection of very rare pathogenic gene variants and uncover cerebral palsy. Herein, we describe two siblings with cerebral palsy due to ELOVL1 splice site mutation in autosomal recessive manner. ELOVL1 catalyzes fatty acid elongation to produce very long-chain fatty acids (VLCFAs; ≥C21), most of which are components of sphingolipids such as ceramides and sphingomyelins. Ichthyotic keratoderma, spasticity, hypomyelination, and dysmorphic facies (MIM: 618527) stem from ELOVL1 gene deficiency in human. METHODS We have studied a consanguineous family with whole exome sequencing (WES) and performed in depth analysis of cryptic splicing on the molecular level using RNA. Comprehensive analysis of ceramides in the skin stratum corneum of patients using liquid chromatography-tandem mass spectrometry (LC-MS/MS). ELOVL1 protein structure was computationally modelled. RESULTS The novel c.376-2A > G (ENST00000372458.8) homozygous variant in the affected siblings causes exon skipping. Comprehensive analysis of ceramides in the skin stratum corneum of patients using LC-MS/MS demonstrated significant shortening of fatty acid moieties and severe reduction in the levels of acylceramides. DISCUSSION It has recently been shown that disease associated variants of ELOVL1 segregate in an autosomal dominant manner. However, our study for the first time demonstrates an alternative autosomal recessive inheritance model for ELOVL1. In conclusion, we suggest that in ultra-rare diseases, being able to identify the inheritance patterns of the disease-associated gene or genes can be an important guide to identifying the molecular mechanism of genetic cerebral palsy.
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Affiliation(s)
- Taiko Takahashi
- Hokkaido University, Faculty of Pharmaceutical Sciences, Laboratory of Biochemistry, Sapporo, Japan
| | - Sevcan Mercan
- Kafkas University, Faculty of Engineering and Architecture, Department of Bioengineering, Kars, Turkey
| | - Takayuki Sassa
- Hokkaido University, Faculty of Pharmaceutical Sciences, Laboratory of Biochemistry, Sapporo, Japan
| | - Günseli Bayram Akçapınar
- Acibadem MAA University, Institute of Health Sciences, Department of Medical Biotechnology, Istanbul, Turkey
| | - Kanay Yararbaş
- Demiroglu Bilim University, Faculty of Medicine, Department of Medical Genetics, Istanbul, Turkey
| | - Seda Süsgün
- Istanbul University, Aziz Sancar Institute of Experimental Medicine, Department of Genetics, Istanbul, Turkey; Istanbul University, Graduate School of Health Sciences, Istanbul, Turkey; Bezmialem Vakif University, Faculty of Medicine, Department of Medical Biology, Istanbul, Turkey
| | - Sibel Aylin Uğur İşeri
- Istanbul University, Aziz Sancar Institute of Experimental Medicine, Department of Genetics, Istanbul, Turkey
| | - Akio Kihara
- Hokkaido University, Faculty of Pharmaceutical Sciences, Laboratory of Biochemistry, Sapporo, Japan
| | - Nihan Hande Akçakaya
- Demiroglu Bilim University, Faculty of Medicine, Department of Neurology, Istanbul, Turkey; Spastic Children's Foundation of Turkey, Cerebral Palsy Turkey, Istanbul, Turkey.
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Ohta K, Hiraki S, Miyanabe M, Ueki T, Manabe Y, Sugawara T. Dietary Ceramide Prepared from Soy Sauce Lees Improves Skin Barrier Function in Hairless Mice. J Oleo Sci 2021; 70:1325-1334. [PMID: 34373410 DOI: 10.5650/jos.ess21128] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dietary sphingolipids such as glucosylceramide and sphingomyelin are known to improve the skin barrier function of damaged skin. In this study, we focused on free-ceramide prepared from soy sauce lees, which is a byproduct of soy sauce production. The effects of dietary soy sauce lees ceramide on the skin of normal mice were evaluated and compared with those of dietary maize glucosylceramide. We found that transepidermal water loss value was significantly suppressed by dietary supplementation with soy sauce lees ceramide as effectively as or more effectively than maize glucosylceramide. Although the content of total and each subclass of ceramide in the epidermis was not significantly altered by dietary sphingolipids, that of 12 types of ceramide molecules, which were not present in dietary sources, was significantly increased upon ingestion of maize glucosylceramide and showed a tendency to increase with soy sauce lees ceramide intake. In addition, the mRNA expression of ceramide synthase 4 and involucrin in the skin was downregulated by sphingolipids. This study, for the first time, demonstrated that dietary soy sauce lees ceramide enhances skin barrier function in normal hairless mice, although further studies are needed to clarify the molecular mechanism.
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Affiliation(s)
- Kazushi Ohta
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University
| | | | | | | | - Yuki Manabe
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University
| | - Tatsuya Sugawara
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University
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