51
|
Local and Systemic Changes in Lipid Profile as Potential Biomarkers for Canine Atopic Dermatitis. Metabolites 2021; 11:metabo11100670. [PMID: 34677385 PMCID: PMC8541266 DOI: 10.3390/metabo11100670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 12/28/2022] Open
Abstract
Lipids play a critical role in the skin as components of the epidermal barrier and as signaling and antimicrobial molecules. Atopic dermatitis in dogs is associated with changes in the lipid composition of the skin, but whether these precede or follow the onset of dermatitis is unclear. We applied rapid lipid-profiling mass spectrometry to skin and blood of 30 control and 30 atopic dogs. Marked differences in lipid profiles were observed between control, nonlesional, and lesional skin. The lipid composition of blood from control and atopic dogs was different, indicating systemic changes in lipid metabolism. Female and male dogs differed in the degree of changes in the skin and blood lipid profiles. Treatment with oclacitinib or lokivetmab ameliorated the skin condition and caused changes in skin and blood lipids. A set of lipid features of the skin was selected as a biomarker that classified samples as control or atopic dermatitis with 95% accuracy, whereas blood lipids discriminated between control and atopic dogs with 90% accuracy. These data suggest that canine atopic dermatitis is a systemic disease and support the use of rapid lipid profiling to identify novel biomarkers.
Collapse
|
52
|
Interleukins 4 and 13 drive lipid abnormalities in skin cells through regulation of sex steroid hormone synthesis. Proc Natl Acad Sci U S A 2021; 118:2100749118. [PMID: 34521750 DOI: 10.1073/pnas.2100749118] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/12/2021] [Indexed: 01/04/2023] Open
Abstract
Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by skin dryness, inflammation, and itch. A major hallmark of AD is an elevation of the immune cytokines IL-4 and IL-13. These cytokines lead to skin barrier disruption and lipid abnormalities in AD, yet the underlying mechanisms are unclear. Sebaceous glands are specialized sebum-producing epithelial cells that promote skin barrier function by releasing lipids and antimicrobial proteins to the skin surface. Here, we show that in AD, IL-4 and IL-13 stimulate the expression of 3β-hydroxysteroid dehydrogenase 1 (HSD3B1), a key rate-limiting enzyme in sex steroid hormone synthesis, predominantly expressed by sebaceous glands in human skin. HSD3B1 enhances androgen production in sebocytes, and IL-4 and IL-13 drive lipid abnormalities in human sebocytes and keratinocytes through HSD3B1. Consistent with our findings in cells, HSD3B1 expression is elevated in the skin of AD patients and can be restored by treatment with the IL-4Rα monoclonal antibody, Dupilumab. Androgens are also elevated in a mouse model of AD, though the mechanism in mice remains unclear. Our findings illuminate a connection between type 2 immunity and sex steroid hormone synthesis in the skin and suggest that abnormalities in sex steroid hormone synthesis may underlie the disrupted skin barrier in AD. Furthermore, targeting sex steroid hormone synthesis pathways may be a therapeutic avenue to restoring normal skin barrier function in AD patients.
Collapse
|
53
|
Ng PSM, Wee LWY, Ho VPY, Tan WC, Bishnoi P, Alagappan U, Wong SMY, Gan EY, Quek BH, Shen L, Su B, Common JE, Koh MJA. Moisturisers from birth in at-risk infants of atopic dermatitis - a pragmatic randomised controlled trial. Australas J Dermatol 2021; 62:e539-e545. [PMID: 34424533 PMCID: PMC9291182 DOI: 10.1111/ajd.13703] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/24/2021] [Accepted: 08/09/2021] [Indexed: 11/30/2022]
Abstract
Background Atopic dermatitis (AD) is a common, chronic dermatosis, with onset of disease often manifesting in early infancy. Past studies evaluating the early use of moisturisers in the prevention of AD had mixed results. Objectives To compare the incidence of moderate or severe AD and total incidence of AD in a cohort of ‘at‐risk’ infants treated with moisturisers from the first 2 weeks of life, to a similar group without moisturisers. Methods We performed a single‐centre, prospective, parallel‐group, randomised study in infants with at least 2 first‐degree relatives with atopy. Subjects were randomised into either a treatment group with moisturisers or a control group without moisturisers. Participants were assessed at 2, 6, and 12 months for AD and if present, the severity was assessed using SCORAD index. We also compared the overall incidence of AD, trans‐epidermal water loss (TEWL), stratum corneum (SC) hydration, pH, and incidence of food and environmental sensitisation and allergies between both groups. Genotyping for loss‐of‐functions mutations in the FLG gene was conducted. Results A total of 200 subjects were recruited, with 100 subjects in each arm. There was no significant difference in incidence of moderate or severe AD, and total incidence of AD at 12 months between the treatment and control groups. There was a lower mean SCORAD in the treatment group than in the control group, but no significant difference in TEWL, SC hydration, and skin pH. No significant side‐effects were reported. Conclusions The early use of moisturisers in ‘at‐risk’ infants does not reduce the incidence of moderate‐to‐severe AD and overall incidence of AD in infancy.
Collapse
Affiliation(s)
- Pamela Si Min Ng
- Department of Paediatric Medicine, KK Women's and Children's Hospital, Singapore
| | | | | | | | - Priya Bishnoi
- Dermatology Service, KK Women's and Children's Hospital, Singapore
| | - Uma Alagappan
- Dermatology Service, KK Women's and Children's Hospital, Singapore
| | | | - Emily Yiping Gan
- Dermatology Service, KK Women's and Children's Hospital, Singapore
| | - Bin Huey Quek
- Department of Neonatology, KK Women's and Children's Hospital, Singapore
| | - Liang Shen
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
| | - Bing Su
- Research Center, KK Women's and Children's Hospital, Singapore
| | - John Ea Common
- Skin Research Institute of Singapore, Agency for Science, Technology and Research (A*STAR), Singapore
| | | |
Collapse
|
54
|
Blicharz L, Rudnicka L, Czuwara J, Waśkiel-Burnat A, Goldust M, Olszewska M, Samochocki Z. The Influence of Microbiome Dysbiosis and Bacterial Biofilms on Epidermal Barrier Function in Atopic Dermatitis-An Update. Int J Mol Sci 2021; 22:ijms22168403. [PMID: 34445108 PMCID: PMC8395079 DOI: 10.3390/ijms22168403] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 07/31/2021] [Accepted: 08/02/2021] [Indexed: 12/13/2022] Open
Abstract
Atopic dermatitis (AD) is a common inflammatory dermatosis affecting up to 30% of children and 10% of adults worldwide. AD is primarily driven by an epidermal barrier defect which triggers immune dysregulation within the skin. According to recent research such phenomena are closely related to the microbial dysbiosis of the skin. There is growing evidence that cutaneous microbiota and bacterial biofilms negatively affect skin barrier function, contributing to the onset and exacerbation of AD. This review summarizes the latest data on the mechanisms leading to microbiome dysbiosis and biofilm formation in AD, and the influence of these phenomena on skin barrier function.
Collapse
Affiliation(s)
- Leszek Blicharz
- Department of Dermatology, Medical University of Warsaw, 02-008 Warsaw, Poland; (L.R.); (J.C.); (A.W.-B.); (M.O.); (Z.S.)
- Correspondence:
| | - Lidia Rudnicka
- Department of Dermatology, Medical University of Warsaw, 02-008 Warsaw, Poland; (L.R.); (J.C.); (A.W.-B.); (M.O.); (Z.S.)
| | - Joanna Czuwara
- Department of Dermatology, Medical University of Warsaw, 02-008 Warsaw, Poland; (L.R.); (J.C.); (A.W.-B.); (M.O.); (Z.S.)
| | - Anna Waśkiel-Burnat
- Department of Dermatology, Medical University of Warsaw, 02-008 Warsaw, Poland; (L.R.); (J.C.); (A.W.-B.); (M.O.); (Z.S.)
| | - Mohamad Goldust
- Department of Dermatology, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany;
| | - Małgorzata Olszewska
- Department of Dermatology, Medical University of Warsaw, 02-008 Warsaw, Poland; (L.R.); (J.C.); (A.W.-B.); (M.O.); (Z.S.)
| | - Zbigniew Samochocki
- Department of Dermatology, Medical University of Warsaw, 02-008 Warsaw, Poland; (L.R.); (J.C.); (A.W.-B.); (M.O.); (Z.S.)
| |
Collapse
|
55
|
Towards Optimal pH of the Skin and Topical Formulations: From the Current State of the Art to Tailored Products. COSMETICS 2021. [DOI: 10.3390/cosmetics8030069] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Acidic pH of the skin surface has been recognized as a regulating factor for the maintenance of the stratum corneum homeostasis and barrier permeability. The most important functions of acidic pH seem to be related to the keratinocyte differentiation process, the formation and function of epidermal lipids and the corneocyte lipid envelope, the maintenance of the skin microbiome and, consequently, skin disturbances and diseases. As acknowledged extrinsic factors that affect skin pH, topically applied products could contribute to skin health maintenance via skin pH value control. The obtained knowledge on skins’ pH could be used in the formulation of more effective topical products, which would add to the development of the so-called products ‘for skin health maintenance’. There is a high level of agreement that topical products should be acidified and possess pH in the range of 4 to 6. However, formulators, dermatologists and consumers would benefit from some more precise guidance concerning favorable products pH values and the selection of cosmetic ingredients which could be responsible for acidification, together with a more extensive understanding of the mechanisms underlaying the process of skin acidification by topical products.
Collapse
|
56
|
Ni J, Hong H, Zhang Y, Tang S, Han Y, Fang Z, Zhang Y, Zhou N, Wang Q, Liu Y, Li Z, Wang Y, Dong M. Development of a non-invasive method for skin cholesterol detection: pre-clinical assessment in atherosclerosis screening. Biomed Eng Online 2021; 20:52. [PMID: 34074299 PMCID: PMC8170999 DOI: 10.1186/s12938-021-00889-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 05/18/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Establishing a high-accuracy and non-invasive method is essential for evaluating cardiovascular disease. Skin cholesterol is a novel marker for assessing the risk of atherosclerosis and can be used as an independent risk factor of early assessment of atherosclerotic risk. METHODS We propose a non-invasive skin cholesterol detection method based on absorption spectroscopy. Detection reagents specifically bind to skin cholesterol and react with indicator to produce colored products, the skin cholesterol content can be obtained through absorption spectrum information on colored products detected by non-invasive technology. Gas chromatography is used to measure cholesterol extracted from the skin to verify the accuracy and reliability of the non-invasive test method. A total of 342 subjects were divided into normal group (n = 115), disease group (n = 110) and risk group (n = 117). All subjects underwent non-invasive skin cholesterol test. The diagnostic accuracy of the measured value was analyzed by receiver-operating characteristic (ROC) curve. RESULTS The proposed method is able to identify porcine skin containing gradient concentration of cholesterol. The values measured by non-invasive detection method were significantly correlated with gas chromatography measured results (r = 0.9074, n = 73, p < 0.001). Bland-Altman bias was - 72.78 ± 20.03 with 95% limits of agreement - 112.05 to - 33.51, falling within the prespecified clinically non-significant range. We further evaluated the method of patients with atherosclerosis and risk population as well as normal group, patients and risk atherosclerosis group exhibited higher skin cholesterol content than normal group (all P < 0.001). The area under the ROC curve for distinguishing Normal/Disease group was 0.8642 (95% confidence interval, 0.8138 to 0.9146), meanwhile, the area under the ROC curve for distinguishing Normal/Risk group was 0.8534 (95% confidence interval, 0.8034 to 0.9034). CONCLUSIONS The method demonstrated its capability of detecting different concentration of skin cholesterol. This non-invasive skin cholesterol detection system may potentially be used as a risk assessment tool for atherosclerosis screening, especially for a large population.
Collapse
Affiliation(s)
- Jingshu Ni
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
- University of Science and Technology of China, Hefei, 230026, China
| | - Haiou Hong
- Health Management Center, First Affiliated Hospital of University of Science and Technology of China, Hefei, China
| | - Yang Zhang
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
- University of Science and Technology of China, Hefei, 230026, China
| | - Shiqi Tang
- Health Management Center, Renmin Hospital of WuHan University, Wuhan, 430060, China
| | - Yongsheng Han
- Department of Cardiovascular Medicine, First Affiliated Hospital of University of Science and Technology of China, Hefei, 230001, China
| | - Zhaohui Fang
- Department of Endocrinology, The First Affiliated Hospital of Anhui University of Traditional Chinese Medicine, Hefei, 230031, China
| | - Yuanzhi Zhang
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
- Wanjiang Center for Development of Emerging Industrial Technology, Tongling, 244000, China
| | - Nan Zhou
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
- Wanjiang Center for Development of Emerging Industrial Technology, Tongling, 244000, China
| | - Quanfu Wang
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
- Wanjiang Center for Development of Emerging Industrial Technology, Tongling, 244000, China
| | - Yong Liu
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
- University of Science and Technology of China, Hefei, 230026, China
- Wanjiang Center for Development of Emerging Industrial Technology, Tongling, 244000, China
| | - Zhongsheng Li
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China
| | - YiKun Wang
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China.
- University of Science and Technology of China, Hefei, 230026, China.
| | - Meili Dong
- Anhui Provincial Engineering Technology Research Center for Biomedical Optical Instrument, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science , Chinese Academy of Sciences, Hefei, 230031, China.
- University of Science and Technology of China, Hefei, 230026, China.
| |
Collapse
|
57
|
Slominski AT, Kim TK, Qayyum S, Song Y, Janjetovic Z, Oak ASW, Slominski RM, Raman C, Stefan J, Mier-Aguilar CA, Atigadda V, Crossman DK, Golub A, Bilokin Y, Tang EKY, Chen JY, Tuckey RC, Jetten AM, Song Y. Vitamin D and lumisterol derivatives can act on liver X receptors (LXRs). Sci Rep 2021; 11:8002. [PMID: 33850196 PMCID: PMC8044163 DOI: 10.1038/s41598-021-87061-w] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/16/2021] [Indexed: 12/11/2022] Open
Abstract
The interactions of derivatives of lumisterol (L3) and vitamin D3 (D3) with liver X receptors (LXRs) were investigated. Molecular docking using crystal structures of the ligand binding domains (LBDs) of LXRα and β revealed high docking scores for L3 and D3 hydroxymetabolites, similar to those of the natural ligands, predicting good binding to the receptor. RNA sequencing of murine dermal fibroblasts stimulated with D3-hydroxyderivatives revealed LXR as the second nuclear receptor pathway for several D3-hydroxyderivatives, including 1,25(OH)2D3. This was validated by their induction of genes downstream of LXR. L3 and D3-derivatives activated an LXR-response element (LXRE)-driven reporter in CHO cells and human keratinocytes, and by enhanced expression of LXR target genes. L3 and D3 derivatives showed high affinity binding to the LBD of the LXRα and β in LanthaScreen TR-FRET LXRα and β coactivator assays. The majority of metabolites functioned as LXRα/β agonists; however, 1,20,25(OH)3D3, 1,25(OH)2D3, 1,20(OH)2D3 and 25(OH)D3 acted as inverse agonists of LXRα, but as agonists of LXRβ. Molecular dynamics simulations for the selected compounds, including 1,25(OH)2D3, 1,20(OH)2D3, 25(OH)D3, 20(OH)D3, 20(OH)L3 and 20,22(OH)2L3, showed different but overlapping interactions with LXRs. Identification of D3 and L3 derivatives as ligands for LXRs suggests a new mechanism of action for these compounds.
Collapse
Affiliation(s)
- Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA.
- Comprehensive Cancer Center, Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, AL, 35249, USA.
- Pathology and Laboratory Medicine Service, VA Medical Center, Birmingham, AL, 35249, USA.
| | - Tae-Kang Kim
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Shariq Qayyum
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Yuwei Song
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Zorica Janjetovic
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Allen S W Oak
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Radomir M Slominski
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Chander Raman
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Joanna Stefan
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
- Department of Oncology, Nicolaus Copernicus University Medical College, Romanowskiej str. 2, 85-796, Bydgoszcz, Poland
| | - Carlos A Mier-Aguilar
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
| | - Venkatram Atigadda
- Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, 35249, USA
| | - David K Crossman
- Department of Genetics, Genomics Core Facility, University of Alabama at Birmingham, Birmingham, AL, 35249, USA
| | | | | | - Edith K Y Tang
- School of Molecular Sciences, The University of Western Australia, Perth, WA, Australia
| | - Jake Y Chen
- Informatics Institute, University of Alabama at Birmingham, Birmingham, AL, 35249, USA
| | - Robert C Tuckey
- School of Molecular Sciences, The University of Western Australia, Perth, WA, Australia
| | - Anton M Jetten
- Cell Biology Section, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, 27709, USA
| | - Yuhua Song
- Department of Biomedical Engineering, University of Alabama at Birmingham, Shelby 803, Birmingham, AL, 35249, USA.
| |
Collapse
|
58
|
Knox S, O'Boyle NM. Skin lipids in health and disease: A review. Chem Phys Lipids 2021; 236:105055. [PMID: 33561467 DOI: 10.1016/j.chemphyslip.2021.105055] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 12/20/2022]
Abstract
Our skin is the interface between us and our environment - a flexible barrier that has evolved for protection, immunity, regulation and sensation. Once regarded as inert, we now know that it is a dynamic environment. Skin lipids are crucial to the structure and function of skin. From deep in the hypodermis, through the ceramide-rich epidermis, to the lipids of the skin surface, there are a vast array of different lipids with important roles to play. This review firstly discusses the lipid composition of human skin and secondly, changes that have been found in skin lipid composition in different skin diseases. Further research into skin lipids facilitated by ever-improving methodologies will no doubt generate new knowledge, paving the way for diagnosis, prevention and treatment of skin disorders and diseases.
Collapse
Affiliation(s)
- Sophie Knox
- School of Pharmacy and Pharmaceutical Sciences, Panoz Institute, Trinity College Dublin, D02 PN40, Ireland
| | - Niamh M O'Boyle
- School of Pharmacy and Pharmaceutical Sciences, Panoz Institute, Trinity College Dublin, D02 PN40, Ireland.
| |
Collapse
|
59
|
Yang M, Zhou M, Li Y, Huang H, Jia Y. Lipidomic analysis of facial skin surface lipid reveals the causes of pregnancy-related skin barrier weakness. Sci Rep 2021; 11:3229. [PMID: 33547383 PMCID: PMC7864992 DOI: 10.1038/s41598-021-82624-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/18/2021] [Indexed: 12/17/2022] Open
Abstract
Self-reported skin discomfort is a common problem during pregnancy, but it is not clear whether skin barrier function is altered in the process. Few studies have described the skin barrier function during pregnancy. In this work, we used highly sensitive and high-resolution ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) to distinguish skin surface lipid (SSL) combined with multivariate analysis of lipids and metabolic changes to determine the relationship between SSL changes and skin physiology during pregnancy in order to better understand the skin condition of pregnant women. The results showed a significant reduction in the total lipid content in pregnant women. A total of 2270 lipids were detected, and the relative abundances of fatty acyls and glycerolipids were significantly reduced, while glycerophospholipids (GPs), sphingolipids, and saccharolipids was significantly increased in the pregnancy group. Multivariate data analysis indicated that 23 entities constituted the most important individual species responsible for the discrimination and phosphatidylcholine was the most abundant lipid in pregnancy group. In addition, compared to SSL profile of control group, it was observed that the average chain length of ceramides and fatty acids both decreased in SSL profile of pregnancy group. The main and most commonly affected pathway was that of GP pathways. These findings indicate that skin lipids are significantly altered in mid-pregnancy compared to the control group. Changes in ostrogen during pregnancy also make the skin more susceptible to inflammatory factors and lead to more fragile and susceptible skin, weakening the skin barrier along with the lipid alterations.
Collapse
Affiliation(s)
- Manli Yang
- Beijing Key Laboratory of Plant Resources Research and Development, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing, 100048, China.,Key Laboratory of Cosmetic of China National Light Industry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing, 100048, China
| | - Mingyue Zhou
- Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, China
| | - Yuan Li
- Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Hong Huang
- Department of Gynecology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Yan Jia
- Beijing Key Laboratory of Plant Resources Research and Development, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing, 100048, China. .,Key Laboratory of Cosmetic of China National Light Industry, College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing, 100048, China.
| |
Collapse
|
60
|
Cohen JD, Sundaram MV. C. elegans Apical Extracellular Matrices Shape Epithelia. J Dev Biol 2020; 8:E23. [PMID: 33036165 PMCID: PMC7712855 DOI: 10.3390/jdb8040023] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 02/07/2023] Open
Abstract
Apical extracellular matrices (aECMs) coat exposed surfaces of epithelia to shape developing tissues and protect them from environmental insults. Despite their widespread importance for human health, aECMs are poorly understood compared to basal and stromal ECMs. The nematode Caenorhabditis elegans contains a variety of distinct aECMs, some of which share many of the same types of components (lipids, lipoproteins, collagens, zona pellucida domain proteins, chondroitin glycosaminoglycans and proteoglycans) with mammalian aECMs. These aECMs include the eggshell, a glycocalyx-like pre-cuticle, both collagenous and chitin-based cuticles, and other understudied aECMs of internal epithelia. C. elegans allows rapid genetic manipulations and live imaging of fluorescently-tagged aECM components, and is therefore providing new insights into aECM structure, trafficking, assembly, and functions in tissue shaping.
Collapse
Affiliation(s)
| | - Meera V. Sundaram
- Department of Genetics, University of Pennsylvania Perelman School of Medicine 415 Curie Blvd, Philadelphia, PA 19104-6145, USA;
| |
Collapse
|
61
|
Patrick GJ, Archer NK, Miller LS. Which Way Do We Go? Complex Interactions in Atopic Dermatitis Pathogenesis. J Invest Dermatol 2020; 141:274-284. [PMID: 32943210 DOI: 10.1016/j.jid.2020.07.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 02/07/2023]
Abstract
Atopic dermatitis (AD) is a common, chronic, inflammatory skin condition characterized by recurrent and pruritic skin eruptions. Multiple factors contribute to the pathogenesis of AD, including skin barrier dysfunction, microbial dysbiosis, and immune dysregulation. Interactions among these factors form a complex, multidirectional network that can reinforce atopic skin disease but can also be ameliorated by targeted therapies. This review summarizes the complex interactions among contributing factors in AD and the implications on disease development and therapeutic interventions.
Collapse
Affiliation(s)
- Garrett J Patrick
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nathan K Archer
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lloyd S Miller
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Janssen Research and Development, Spring House, Pennsylvania, USA.
| |
Collapse
|
62
|
Myles IA, Castillo CR, Barbian KD, Kanakabandi K, Virtaneva K, Fitzmeyer E, Paneru M, Otaizo-Carrasquero F, Myers TG, Markowitz TE, Moore IN, Liu X, Ferrer M, Sakamachi Y, Garantziotis S, Swamydas M, Lionakis MS, Anderson ED, Earland NJ, Ganesan S, Sun AA, Bergerson JRE, Silverman RA, Petersen M, Martens CA, Datta SK. Therapeutic responses to Roseomonas mucosa in atopic dermatitis may involve lipid-mediated TNF-related epithelial repair. Sci Transl Med 2020; 12:eaaz8631. [PMID: 32908007 PMCID: PMC8571514 DOI: 10.1126/scitranslmed.aaz8631] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 01/03/2020] [Accepted: 03/12/2020] [Indexed: 07/30/2023]
Abstract
Dysbiosis of the skin microbiota is increasingly implicated as a contributor to the pathogenesis of atopic dermatitis (AD). We previously reported first-in-human safety and clinical activity results from topical application of the commensal skin bacterium Roseomonas mucosa for the treatment of AD in 10 adults and 5 children older than 9 years of age. Here, we examined the potential mechanism of action of R. mucosa treatment and its impact on children with AD less than 7 years of age, the most common age group for children with AD. In 15 children with AD, R. mucosa treatment was associated with amelioration of disease severity, improvement in epithelial barrier function, reduced Staphylococcus aureus burden on the skin, and a reduction in topical steroid requirements without severe adverse events. Our observed response rates to R. mucosa treatment were greater than those seen in historical placebo control groups in prior AD studies. Skin improvements and colonization by R. mucosa persisted for up to 8 months after cessation of treatment. Analyses of cellular scratch assays and the MC903 mouse model of AD suggested that production of sphingolipids by R. mucosa, cholinergic signaling, and flagellin expression may have contributed to therapeutic impact through induction of a TNFR2-mediated epithelial-to-mesenchymal transition. These results suggest that a randomized, placebo-controlled trial of R. mucosa treatment in individuals with AD is warranted and implicate commensals in the maintenance of the skin epithelial barrier.
Collapse
Affiliation(s)
- Ian A Myles
- Epithelial Therapeutics Unit, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD, USA.
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| | - Carlo R Castillo
- Epithelial Therapeutics Unit, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD, USA
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| | - Kent D Barbian
- RTS Genomics Unit, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | - Kishore Kanakabandi
- RTS Genomics Unit, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | - Kimmo Virtaneva
- RTS Genomics Unit, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | - Emily Fitzmeyer
- RTS Genomics Unit, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | - Monica Paneru
- RTS Genomics Unit, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | | | | | - Tovah E Markowitz
- NIAID Collaborative Bioinformatics Resource (NCBR), NIAID, NIH, Bethesda, MD, USA
- Advanced Biomedical Computational Science, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Ian N Moore
- Infectious Disease Pathogenesis Section, Comparative Medicine Branch, NIAID, NIH, Rockville, MD, USA
| | - Xue Liu
- Department of Pre-clinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
| | - Marc Ferrer
- Department of Pre-clinical Innovation, National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
| | - Yosuke Sakamachi
- National Institute of Environmental Health Sciences, Research Triangle, NC, USA
| | | | | | | | - Erik D Anderson
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| | - Noah J Earland
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| | - Sundar Ganesan
- Biological Imaging Section, Research Technology Branch, NIAID, NIH, Bethesda, MD, USA
| | - Ashleigh A Sun
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| | - Jenna R E Bergerson
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| | - Robert A Silverman
- Department of Pediatrics, Georgetown University Hospital, Washington, DC, USA
| | | | - Craig A Martens
- RTS Genomics Unit, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT, USA
| | - Sandip K Datta
- Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD, USA
| |
Collapse
|
63
|
The Role of the Microbiome and Microbiome-Derived Metabolites in Atopic Dermatitis and Non-Histaminergic Itch. Am J Clin Dermatol 2020; 21:44-50. [PMID: 32910440 PMCID: PMC7584541 DOI: 10.1007/s40257-020-00538-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Recent advances in our understanding of the pathophysiology of atopic dermatitis (AD) have revealed that skin microbiome dysbiosis plays an important role in the disease. In this review, we describe how changes in the structure and function of the microbiome are involved in the pathogenesis of AD. We highlight recent data showing that differential changes in microbial diversity, both within and across communities from different body habitats (including the skin, gut, and oral mucosa), are associated with the development and severity of AD. We also describe recent evidence demonstrating that the metabolic activity of the skin microbiome can act as a regulator of inflammation, with alterations in the level of a skin microbiome-derived tryptophan metabolite, indole-3-aldehyde (IAId), being shown to play a role in AD. The various mechanisms by which interactions between the microbiome and components of the non-histaminergic pathway result in itch in AD are also discussed.
Collapse
|
64
|
Ma X, Lu L, Zhao Z, Cai M, Gao N, Han G. Lipidomics profiling of skin surface lipids in senile pruritus. Lipids Health Dis 2020; 19:171. [PMID: 32677954 PMCID: PMC7364579 DOI: 10.1186/s12944-020-01347-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/09/2020] [Indexed: 12/05/2022] Open
Abstract
Background Senile pruritus is common, yet its etiology remains unknown. Aging-associated skin barrier defects and skin surface lipid (SSL) alterations have been postulated to play important roles in its occurrence. In the present study, the lipidomic profiles of SSLs in elderly patients were examined to better understand the potential causes of senile pruritus. Methods Transepidermal water loss (TEWL) was evaluated to assess the skin barrier function. The Ameliorated Kawashima Itch Scale score was used to measure the pruritus severity. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and multivariate data analysis were employed to investigate SSL alterations. Results The results showed that senile pruritus patients had higher TEWL values than control subjects (13.13 ± 4.28 versus 6.71 ± 2.45, p < 0.01). LC-MS/MS revealed significant differences in the lipidomic profiles and identified 81 species of SSLs that differed between the two groups. Compared with control subjects, senile pruritus patients had increased levels of ceramides (Cers), diacylglycerols, fatty acids, phosphatidylcholines, phosphatidylethanolamines, phytosphingosines, sphingosines, diacylceryl-3-O-carboxyhydroxymethylcholine, diacylglyceryl trimethylhomoserine, and unsaturated free fatty acids, but decreased levels of triacylglycerol. Cer-EOS, Cer-NDS, and Cer-NS were positively correlated with TEWL value (p < 0.05). Pruritus severity score was positively correlated with sphingomyelin, Cer-NP, Cer-AS, Cer-NDS, and Cer-NS, but negatively correlated with Cer-BS, Cer-EODS, Cer-EOS, and Cer-AP. Conclusions The present study indicated that patients with senile pruritus have impaired skin barrier function and altered SSL composition. Certain SSL species identified in this study may be potential targets for future studies on the pathogenesis of senile pruritus. Trial registration Peking University International Hospital (Number: YN2018QN04; date: January 2019).
Collapse
Affiliation(s)
- Xiaolei Ma
- Department of Dermatology, Peking University International Hospital, Life Park Road No.1, Life Science Park of Zhong Guancun, Changping District, Beijing, 102206, China.
| | - Lulu Lu
- Department of Dermatology, Peking University International Hospital, Life Park Road No.1, Life Science Park of Zhong Guancun, Changping District, Beijing, 102206, China
| | - Zheng Zhao
- Department of Dermatology, Peking University International Hospital, Life Park Road No.1, Life Science Park of Zhong Guancun, Changping District, Beijing, 102206, China
| | - Mingru Cai
- Department of Dermatology, Peking University International Hospital, Life Park Road No.1, Life Science Park of Zhong Guancun, Changping District, Beijing, 102206, China
| | - Na Gao
- Department of Dermatology, Peking University International Hospital, Life Park Road No.1, Life Science Park of Zhong Guancun, Changping District, Beijing, 102206, China
| | - Gangwen Han
- Department of Dermatology, Peking University International Hospital, Life Park Road No.1, Life Science Park of Zhong Guancun, Changping District, Beijing, 102206, China.
| |
Collapse
|
65
|
Excessive cleansing: an underestimating risk factor of rosacea in Chinese population. Arch Dermatol Res 2020; 313:225-234. [PMID: 32594335 DOI: 10.1007/s00403-020-02095-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 05/11/2020] [Accepted: 06/17/2020] [Indexed: 10/24/2022]
Abstract
Appropriate skincare is essential in the prevention and management of rosacea. We sought to investigate whether cleansing habits, the initial step of skin care, would influence the onset and progression of rosacea and their associations with clinical features of rosacea in the Chinese population. We analyzed the daily cleansing habits data collected from 999 rosacea cases and 1010 skin-healthy controls from China. Overall, the high frequency of cleansing (more than once daily) (OR = 1.450) and the large amount of cleansers (> 5 pieces/year) (OR = 1.612) presented a positive correlation with rosacea occurring. The cleansing duration and types of cleansers appeared not to be correlated with the onset of rosacea in this study. Significant risk factors also included the deep cleansing habits, such as the overuse of cleansing tool (more than four times/week) (OR 2.179) and oil control and exfoliating behaviors via daily used products (OR 2.435), facial mask (OR 1.459) or projects in beauty salons (OR 2.688). The analysis of the clinical features of rosacea showed that patients who prefer deep cleansing were more prone to present an initial symptom of papule and pustule (OR 1.63-3.15). What is more, using daily exfoliating products presented a positive correlation with the progression of the symptoms from flushing to erythema (OR = 2.01), papule and pustule (OR = 2.28) and telangiectasis (OR = 2.14), and the affected areas from a single area to pan facial (OR = 1.650). In conclusion, excessive cleansing habits were substantial risk factors for the incidence and progression of rosacea in the Chinese population.
Collapse
|
66
|
Topical Pioglitazone Nanoformulation for the Treatment of Atopic Dermatitis: Design, Characterization and Efficacy in Hairless Mouse Model. Pharmaceutics 2020; 12:pharmaceutics12030255. [PMID: 32178278 PMCID: PMC7150908 DOI: 10.3390/pharmaceutics12030255] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/09/2020] [Accepted: 03/09/2020] [Indexed: 12/17/2022] Open
Abstract
Pioglitazone (PGZ) is a drug used to treat type 2 diabetes mellitus that has been reported to show additional therapeutic activities on diverse inflammatory parameters. The aim of this study was to optimize a topical PGZ-loaded nanoemulsion (PGZ-NE) in order to evaluate its effectiveness for treating atopic dermatitis (AD). The composition of the nanoformulation was established by pseudo-ternary diagram. Parameters such as physical properties, stability, in vitro release profile, and ex vivo permeation were determined. The efficacy study was carried out using oxazolone-induced AD model in hairless mice. PGZ-NE released the drug following a hyperbolic kinetic. Additionally, its properties provided high retention potential of drug inside the skin. Therapeutic benefits of PGZ-NE were confirmed on diverse events of the inflammatory process, such as reduction of lesions, enhancement of skin barrier function, diminished infiltration of inflammatory cells, and expression of pro-inflammatory cytokines. These results were reinforced by atomic force microscope (AFM), which demonstrated the ability of the formulation to revert the rigidification caused by oxazolone and consequently improve the elasticity of the skin. These results suggest that PGZ-NE may be a promising treatment for inflammatory dermatological conditions such as AD.
Collapse
|
67
|
Molecular Mechanism of Epidermal Barrier Dysfunction as Primary Abnormalities. Int J Mol Sci 2020; 21:ijms21041194. [PMID: 32054030 PMCID: PMC7072774 DOI: 10.3390/ijms21041194] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/08/2020] [Accepted: 02/09/2020] [Indexed: 02/07/2023] Open
Abstract
Epidermal barrier integrity could be influenced by various factors involved in epidermal cell differentiation and proliferation, cell–cell adhesion, and skin lipids. Dysfunction of this barrier can cause skin disorders, including eczema. Inversely, eczema can also damage the epidermal barrier. These interactions through vicious cycles make the mechanism complicated in connection with other mechanisms, particularly immunologic responses. In this article, the molecular mechanisms concerning epidermal barrier abnormalities are reviewed in terms of the following categories: epidermal calcium gradients, filaggrin, cornified envelopes, desquamation, and skin lipids. Mechanisms linked to ichthyoses, atopic dermatitis without exacerbation or lesion, and early time of experimental irritation were included. On the other hand, the mechanism associated with epidermal barrier abnormalities resulting from preceding skin disorders was excluded. The molecular mechanism involved in epidermal barrier dysfunction has been mostly episodic. Some mechanisms have been identified in cultured cells or animal models. Nonetheless, research into the relationship between the causative molecules has been gradually increasing. Further evidence-based systematic data of target molecules and their interactions would probably be helpful for a better understanding of the molecular mechanism underlying the dysfunction of the epidermal barrier.
Collapse
|
68
|
Minzaghi D, Pavel P, Dubrac S. Xenobiotic Receptors and Their Mates in Atopic Dermatitis. Int J Mol Sci 2019; 20:E4234. [PMID: 31470652 PMCID: PMC6747412 DOI: 10.3390/ijms20174234] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/19/2019] [Accepted: 08/26/2019] [Indexed: 02/07/2023] Open
Abstract
Atopic dermatitis (AD) is the most common inflammatory skin disease worldwide. It is a chronic, relapsing and pruritic skin disorder which results from epidermal barrier abnormalities and immune dysregulation, both modulated by environmental factors. AD is strongly associated with asthma and allergic rhinitis in the so-called 'atopic march.' Xenobiotic receptors and their mates are ligand-activated transcription factors expressed in the skin where they control cellular detoxification pathways. Moreover, they regulate the expression of genes in pathways involved in AD in epithelial cells and immune cells. Activation or overexpression of xenobiotic receptors in the skin can be deleterious or beneficial, depending on context, ligand and activation duration. Moreover, their impact on skin might be amplified by crosstalk among xenobiotic receptors and their mates. Because they are activated by a broad range of endogenous molecules, drugs and pollutants owing to their promiscuous ligand affinity, they have recently crystalized the attention of researchers, including in dermatology and especially in the AD field. This review examines the putative roles of these receptors in AD by critically evaluating the conditions under which the proteins and their ligands have been studied. This information should provide new insights into AD pathogenesis and ways to develop new therapeutic interventions.
Collapse
Affiliation(s)
- Deborah Minzaghi
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Petra Pavel
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Sandrine Dubrac
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, 6020 Innsbruck, Austria.
| |
Collapse
|
69
|
Ding X, Willenborg S, Bloch W, Wickström SA, Wagle P, Brodesser S, Roers A, Jais A, Brüning JC, Hall MN, Rüegg MA, Eming SA. Epidermal mammalian target of rapamycin complex 2 controls lipid synthesis and filaggrin processing in epidermal barrier formation. J Allergy Clin Immunol 2019; 145:283-300.e8. [PMID: 31401286 DOI: 10.1016/j.jaci.2019.07.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 06/21/2019] [Accepted: 07/08/2019] [Indexed: 12/31/2022]
Abstract
BACKGROUND Perturbation of epidermal barrier formation will profoundly compromise overall skin function, leading to a dry and scaly, ichthyosis-like skin phenotype that is the hallmark of a broad range of skin diseases, including ichthyosis, atopic dermatitis, and a multitude of clinical eczema variants. An overarching molecular mechanism that orchestrates the multitude of factors controlling epidermal barrier formation and homeostasis remains to be elucidated. OBJECTIVE Here we highlight a specific role of mammalian target of rapamycin complex 2 (mTORC2) signaling in epidermal barrier formation. METHODS Epidermal mTORC2 signaling was specifically disrupted by deleting rapamycin-insensitive companion of target of rapamycin (Rictor), encoding an essential subunit of mTORC2 in mouse epidermis (epidermis-specific homozygous Rictor deletion [RicEKO] mice). Epidermal structure and barrier function were investigated through a combination of gene expression, biochemical, morphological and functional analysis in RicEKO and control mice. RESULTS RicEKO newborns displayed an ichthyosis-like phenotype characterized by dysregulated epidermal de novo lipid synthesis, altered lipid lamellae structure, and aberrant filaggrin (FLG) processing. Despite a compensatory transcriptional epidermal repair response, the protective epidermal function was impaired in RicEKO mice, as revealed by increased transepidermal water loss, enhanced corneocyte fragility, decreased dendritic epidermal T cells, and an exaggerated percutaneous immune response. Restoration of Akt-Ser473 phosphorylation in mTORC2-deficient keratinocytes through expression of constitutive Akt rescued FLG processing. CONCLUSION Our findings reveal a critical metabolic signaling relay of barrier formation in which epidermal mTORC2 activity controls FLG processing and de novo epidermal lipid synthesis during cornification. Our findings provide novel mechanistic insights into epidermal barrier formation and could open up new therapeutic opportunities to restore defective epidermal barrier conditions.
Collapse
Affiliation(s)
- Xiaolei Ding
- Department of Dermatology, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | | | - Wilhelm Bloch
- Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Cologne, Germany
| | - Sara A Wickström
- Paul Gerson Unna Group "Skin Homeostasis and Ageing", Max Planck Institute for Biology of Ageing, Cologne, Germany; Helsinki Institute of Life Science, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland; Wihuri Research Institute, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland; Cluster of Excellence Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Prerana Wagle
- Cluster of Excellence Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Susanne Brodesser
- Cluster of Excellence Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Axel Roers
- Institute for Immunology, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Alexander Jais
- Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Jens C Brüning
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany; Cluster of Excellence Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany; Max Planck Institute for Metabolism Research, Cologne, Germany
| | | | | | - Sabine A Eming
- Department of Dermatology, University of Cologne, Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany; Cluster of Excellence Cellular Stress Responses in Aging-associated Diseases (CECAD), University of Cologne, Cologne, Germany.
| |
Collapse
|