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Raabe HA, Costin GE, Allen DG, Lowit A, Corvaro M, O'Dell L, Breeden-Alemi J, Page K, Perron M, Flint Silva T, Westerink W, Baker E, Sullivan K. Human relevance of in vivo and in vitro skin irritation tests for hazard classification of pesticides. Cutan Ocul Toxicol 2024:1-21. [PMID: 39180341 DOI: 10.1080/15569527.2024.2387596] [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: 04/02/2024] [Accepted: 07/24/2024] [Indexed: 08/26/2024]
Abstract
Background: Test methods to inform hazard characterization and labeling of pesticides to protect human health are typically conducted using laboratory animals, and for skin irritation/corrosion the rabbit Draize test is currently required by many regulatory agencies. Although the Draize test is generally regarded to provide protective classifications for human health, new approach methodologies (NAMs) have been developed that offer more human relevant models that circumvent the uncertainty associated with species differences that exist between rabbits and humans. Despite wide applicability and use of these test methods across a broad range of chemicals, they have not been widely adopted for testing pesticides and pesticidal formulations. One of the barriers to adoption of these methods in this sector is low concordance with results from the Draize rabbit test, particularly for chemicals within the mild to moderate irritation spectrum. Methods: This review compares and contrasts the extent to which available models used in skin irritation testing mimic the anatomy and physiology of human skin, and how each aligns with the known key events leading to chemically-induced adverse skin irritation and corrosion. Doing so fully characterizes the human relevance of each method. Results: As alternatives to the rabbit Draize test, several protocols using ex vivo, in chemico, and in vitro skin models are available as internationally harmonized test guidelines. These methods rely on a variety of models of human skin, including excised rodent skin, synthetic biochemical models of barrier function, cell culture systems, and reconstructed human tissue models. We find these models exhibit biological and mechanistic relevance aligned with human skin irritation responses. Further, recent retrospective analyses have shown that the reproducibility of the Draize test is less than 50% for mild and moderate responses, with many of the replicate predictions spanning more than one category (e.g., a moderate response reported in one study followed by a non-irritant response reported in another study). Conclusions: Based on this comparative evaluation, we recommend top-down and bottom-up testing strategies that use the most human relevant in vitro test methods for skin irritation and corrosion classification of pesticides and pesticide formulations. To further discriminate among mild and non-irritant formulations, optimization of a cytokine release protocol and subsequent analyses of reference formulation test results is recommended.
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Affiliation(s)
- Hans A Raabe
- Institute for In Vitro Sciences, Gaithersburg, MD, USA
| | | | | | - Anna Lowit
- US Environmental Protection Agency, Washington, DC, USA
| | | | | | | | | | | | | | | | - Elizabeth Baker
- Physicians Committee for Responsible Medicine, Washington, DC, USA
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2
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Miguel RDA, Hirata AS, Salata GC, Apolinário AC, Barroso VM, Ishida K, La Clair JJ, Fenical W, Martins TS, Costa-Lotufo LV, Lopes LB. Topical delivery of seriniquinone for treatment of skin cancer and fungal infections is enabled by a liquid crystalline lamellar phase. Eur J Pharm Sci 2024; 192:106635. [PMID: 37952683 DOI: 10.1016/j.ejps.2023.106635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 10/23/2023] [Accepted: 11/10/2023] [Indexed: 11/14/2023]
Abstract
Seriniquinone (SQ) was initially described by our group as an antimelanoma drug candidate and now also as an antifungal drug candidate. Despite its promising in vitro effects, SQ translation has been hindered by poor water-solubility. In this paper, we described the challenging nanoformulation process of SQ, which culminated in the selection of a phosphatidylcholine-based lamellar phase (PLP1). Liposomes and nanostructured lipid carriers were also evaluated but failed to encapsulate the compound. SQ-loaded PLP1 (PLP1-SQ) was characterized for the presence of sedimented or non-dissolved SQ, rheological and thermal behavior, and irritation potential with hen's egg test on the chorioallantoic membrane (HET-CAM). PLP1 influence on transepidermal water loss (TEWL) and skin penetration of SQ was assessed in a porcine ear skin model, while biological activity was evaluated against melanoma cell lines (SK-MEL-28 and SK-MEL-147) and C. albicans SC5314. Despite the presence of few particles of non-dissolved SQ (observed under the microscope 2 days after formulation obtainment), PLP1 tripled SQ retention in viable skin layers compared to SQ solution at 12 h. This effect did not seem to relate to formulation-induced changes on the barrier function, as no increases in TEWL were observed. No sign of vascular toxicity in the HET-CAM model was observed after cutaneous treatment with PLP1. SQ activity was maintained on melanoma cells after 48 h-treatment (IC50 values of 0.59-0.98 µM) whereas the minimum inhibitory concentration (MIC) against C. albicans after 24 h-treatment was 32-fold higher. These results suggest that a safe formulation for SQ topical administration was developed, enabling further in vivo studies.
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Affiliation(s)
- Rodrigo Dos A Miguel
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Amanda S Hirata
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Giovanna C Salata
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Alexsandra C Apolinário
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Vinicius M Barroso
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Kelly Ishida
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - James J La Clair
- Department of Chemistry and Biochemistry, University of California, La Jolla, San Diego, CA, United States
| | - William Fenical
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, La Jolla, San Diego, CA, United States
| | - Tereza S Martins
- Department of Chemistry, Federal University of Sao Paulo, Diadema, SP, Brazil
| | - Leticia V Costa-Lotufo
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil; Department of Human Biology, University of Cape Town, Cape Town, South Africa.
| | - Luciana B Lopes
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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Lepoittevin JP, Lafforgue C. Molecular Aspects in Allergic and Irritant Contact Dermatitis. Contact Dermatitis 2021. [DOI: 10.1007/978-3-030-36335-2_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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4
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Lepoittevin JP, Lafforgue C. Molecular Aspects in Allergic and Irritant Contact Dermatitis. Contact Dermatitis 2020. [DOI: 10.1007/978-3-319-72451-5_4-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Kose O, Erkekoglu P, Sabuncuoglu S, Kocer-Gumusel B. Evaluation of skin irritation potentials of different cosmetic products in Turkish market by reconstructed human epidermis model. Regul Toxicol Pharmacol 2018; 98:268-273. [DOI: 10.1016/j.yrtph.2018.08.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 07/20/2018] [Accepted: 08/19/2018] [Indexed: 10/28/2022]
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6
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Seweryn A. Interactions between surfactants and the skin - Theory and practice. Adv Colloid Interface Sci 2018; 256:242-255. [PMID: 29685575 DOI: 10.1016/j.cis.2018.04.002] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 01/14/2023]
Abstract
One of the primary causes of skin irritation is the use of body wash cosmetics and household chemicals, since they are in direct contact with the skin, and they are widely available and frequently used. The main ingredients of products of this type are surfactants, which may have diverse effects on the skin. The skin irritation potential of surfactants is determined by their chemical and physical properties resulting from their structure, and specific interactions with the skin. Surfactants are capable of interacting both with proteins and lipids in the stratum corneum. By penetrating through this layer, surfactants are also able to affect living cells in deeper regions of the skin. Further skin penetration may result in damage to cell membranes and structural components of keratinocytes, releasing proinflammatory mediators. By causing irreversible changes in cell structure, surfactants can often lead to their death. The paper presents a critical review of literature on the effects of surfactants on the skin. Aspects discussed in the paper include the skin irritation potential of surfactants, mechanisms underlying interactions between compounds of this type and the skin which have been proposed over the years, and verified methods of reducing the skin irritation potential of surfactant compounds. Basic research conducted in this field over many years translate into practical applications of surfactants in the cosmetic and household chemical industries. This aspect is also emphasized in the present study.
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Comparative assessment of local tolerance of alcohols commonly used in alcohol-based hand rubs for hand hygiene. Toxicol In Vitro 2017; 44:142-153. [PMID: 28700953 DOI: 10.1016/j.tiv.2017.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/05/2017] [Accepted: 07/07/2017] [Indexed: 11/21/2022]
Abstract
Hand hygiene plays a key role in nosocomial infection prevention. To achieve users' adherence, products' dermal tolerance is essential. We aimed at making a comparative assessment of skin irritation and phototoxicity of the 3 alcohols commonly used in alcohol-based hand rubs (Ethanol, Propan-2-ol, Propan-1-ol) at 60, 70, 80 or 85% w/w in water or with co-formulates (hydrating, emollient and skin protective agents). In vitro validated OECD methods 439 and 432 were used. For irritation, EpiSkin™ Small Model was the chosen Reconstructed Human Epidermis (RhE). For phototoxicity, co-formulates alone or in mixture with and without alcohol were tested using BALB/c 3T3 cell cultures. Whilst Ethanol and Propan-2-ol could not be differentiated and displayed good skin tolerance profiles, Propan-1-ol based products lead to significant viability impairments of RhE at 60, 70 or 80% and at 60% in the presence of co-formulates. However, these results could not be reproduced in another RhE model. Taking also into account bibliographic data on Propan-1-ol, this suggests that our results are probably related to a lack of specificity of the used RhE. Therefore, it can be relevant in case of significant results to use two different RhE models before performing any classification and/or performing any complementary tests.
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8
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Trop-Steinberg S, Azar Y. Is Myc an Important Biomarker? Myc Expression in Immune Disorders and Cancer. Am J Med Sci 2017; 355:67-75. [PMID: 29289266 DOI: 10.1016/j.amjms.2017.06.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 05/17/2017] [Accepted: 06/14/2017] [Indexed: 01/08/2023]
Abstract
The proto-oncogene Myc serves as a paradigm for understanding the dynamics of transcriptional regulation. Myc protein has been linked to immune dysfunction, cancer development and neoplastic transformation. We review recent research regarding functions of Myc as an important modulator in immune disorders, postallogeneic hematopoietic stem cell transplantation (HSCT) and several cancers. Myc overexpression has been repeatedly linked to immune disorders and specific cancers, such as myasthenia gravis, psoriasis, pemphigus vulgaris, atherosclerosis, long-term allogeneic survival among HSCT patients, (primary) inflammatory breast cancer, (primary) ovarian carcinoma and hematological malignancies: acute myeloid leukemia, chronic myelogenous leukemia, Hodgkin's lymphoma and diffuse large B-cell lymphoma. However, decreased expression of Myc has been observed in HSCT patients who did not survive. Understanding impaired or inappropriate expression of Myc may present a path for the discovery of new targets for therapeutic applications.
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Affiliation(s)
- Shivtia Trop-Steinberg
- Faculty of Life and Health Sciences (ST-S), JCT Lev Academic Institute, Jerusalem, Israel.
| | - Yehudit Azar
- Department of Bone Marrow Transplantation (YA), Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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Catlin NR, Herbert R, Janardhan K, Hejtmancik MR, Fomby LM, Vallant M, Kissling GE, DeVito MJ. Dose-response assessment of the dermal toxicity of Virginia cedarwood oil in F344/N rats and B6C3F1/N mice. Food Chem Toxicol 2016; 98:159-168. [PMID: 27769849 DOI: 10.1016/j.fct.2016.10.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/26/2016] [Accepted: 10/17/2016] [Indexed: 12/15/2022]
Abstract
Virginia cedarwood oil is widely used as a fragrance material in household and personal products and as a naturally derived pesticide alternative. Due to conflicting literature on dermal exposures in animals and humans, concern for safe levels of human exposure remains. The present study evaluated the toxicity of cedarwood oil applied dermally to F344/N rats and B6C3F1/N mice for 13 weeks. Groups of 10 male and female rats and mice received no treatment (untreated control) or were administered cedarwood oil in 95% aqueous ethanol dermally at concentrations ranging from 0% (vehicle control), 6.25%, 12.5%, 25%, 50%, and 100% (undiluted). Rats and mice developed extensive skin lesions at the site of application. Benchmark dose modeling (BMD) was performed for the significantly increased skin lesions observed in the rat, to provide perspective for risk assessment applications. Benchmark dose modeling levels (BMDL) of 0.65 to 2.1% and 1.2 to 4.4% (equivalent to 13 to 42 mg/kg and 24 to 48 mg/kg, respectively) cedarwood oil were calculated for the most sensitive endpoint of epidermal hyperplasia in female rats and chronic active inflammation in male rats, respectively. These BMDL levels coincide with reported use levels in cosmetics and pesticides, raising the concern for human exposure.
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Affiliation(s)
- Natasha R Catlin
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
| | - Ron Herbert
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | | | | | | | - Molly Vallant
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Grace E Kissling
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Michael J DeVito
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
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10
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Igielska-Kalwat J, Gościańska J, Witkowska B, Nowak I. In vivo studies of substances used in the cosmetic industry. Postepy Dermatol Alergol 2016; 33:163-9. [PMID: 27512349 PMCID: PMC4969411 DOI: 10.5114/ada.2016.60607] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 10/20/2014] [Indexed: 11/17/2022] Open
Abstract
Cosmetic producers are obliged to guarantee the safety and stability of their products. The current legal regulations are based on the European Union Directive (1223/2009) of 30 November 2009. The main aim of the directive is to formulate criteria of safety of a cosmetic product and requirements that it must meet to be placed on the market. A new cosmetic product is subjected to thorough investigation prior to its introduction on the market. It should be studied not only with respect to its safety, but also with respect to its effectiveness declared by the producer. The studies are performed in vivo, by the contact or epidermal patch tests on the human skin.
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Affiliation(s)
- Joanna Igielska-Kalwat
- Faculty of Chemistry, Laboratory of Applied Chemistry, Adam Mickiewicz University, Poznan, Poland
| | - Joanna Gościańska
- Faculty of Chemistry, Laboratory of Applied Chemistry, Adam Mickiewicz University, Poznan, Poland
| | - Beata Witkowska
- Faculty of Chemistry, Laboratory of Applied Chemistry, Adam Mickiewicz University, Poznan, Poland
| | - Izabela Nowak
- Faculty of Chemistry, Laboratory of Applied Chemistry, Adam Mickiewicz University, Poznan, Poland
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11
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Wan MJ, Su XY, Zheng Y, Gong ZJ, Yi JL, Zhao Y, Guan XM, Lai W. Seasonal variability in the biophysical properties of forehead skin in women in Guangzhou City, China. Int J Dermatol 2014; 54:1319-24. [PMID: 25557023 DOI: 10.1111/ijd.12741] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 02/12/2014] [Accepted: 04/19/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Miao-Jian Wan
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Xiang-Yang Su
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Yue Zheng
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Zi-Jian Gong
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Jin-Ling Yi
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Yue Zhao
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Xiao-Min Guan
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
| | - Wei Lai
- Department of Dermatology; Third Affiliated Hospital of Sun Yat-San University; Guangzhou China
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12
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In Vitro Cytotoxicity and Phototoxicity Assessment of Acylglutamate Surfactants Using a Human Keratinocyte Cell Line. COSMETICS 2014. [DOI: 10.3390/cosmetics1030159] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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13
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Surh I, Rao DB, Cesta MF, Hébert CD, Mann JF, Cunny H, Kissling GE, Malarkey D, Chhabra RS. Species and gender differences in the carcinogenic activity of trimethylolpropane triacrylate in rats and mice. Food Chem Toxicol 2014; 66:254-61. [PMID: 24503412 DOI: 10.1016/j.fct.2014.01.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 11/28/2022]
Abstract
Trimethylolpropane triacrylate (TMPTA) is a multifunctional monomer with industrial applications. To determine the carcinogenic potential, male and female F344/N rats and B6C3F1/N mice were administered TMPTA (0, 0.3, 1.0, or 3.0mg/kg) in acetone dermally for 2 years. There were no differences in the body weights and survival in the treated animals compared to controls. Nonneoplastic skin lesions at the site of application included epidermal hyperplasia and hyperkeratosis in both rats and mice. There were no incidences of tumors at the site of application in rats and mice. Rare malignant liver neoplasms were observed in female mice that included hepatoblastoma in the 0.3 and 3.0mg/kg groups, and hepatocholangiocarcinoma in the 1.0 and 3.0mg/kg groups. The incidences of uterine stromal polyp and stromal polyp or stromal sarcoma (combined) in female mice occurred with positive trends and the incidences were significantly increased in the 3.0mg/kg group. A marginal increase in the incidences of malignant mesothelioma in male rats may have been related to TMPTA treatment. In conclusion, our studies show that TMPTA is a dermal irritant in both rats and mice of either sex. Increased incidences of tumor formation were observed in female mice and male rats.
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Affiliation(s)
- Inok Surh
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
| | - Deepa B Rao
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA; Integrated Laboratory Systems, Inc., Research Triangle Park, NC 27709, USA
| | - Mark F Cesta
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | | | - Jill F Mann
- Southern Research Institute, Birmingham, AL 35255, USA
| | - Helen Cunny
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Grace E Kissling
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - David Malarkey
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
| | - Rajendra S Chhabra
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA
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Chen Y, Wang M, Fang L. Biomaterials as novel penetration enhancers for transdermal and dermal drug delivery systems. Drug Deliv 2013; 20:199-209. [DOI: 10.3109/10717544.2013.801533] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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15
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Donnelly RF, Singh TRR, Garland MJ, Migalska K, Majithiya R, McCrudden CM, Kole PL, Mahmood TMT, McCarthy HO, Woolfson AD. Hydrogel-Forming Microneedle Arrays for Enhanced Transdermal Drug Delivery. ADVANCED FUNCTIONAL MATERIALS 2012; 22:4879-4890. [PMID: 23606824 PMCID: PMC3627464 DOI: 10.1002/adfm.201200864] [Citation(s) in RCA: 374] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 06/06/2012] [Indexed: 05/17/2023]
Abstract
Unique microneedle arrays prepared from crosslinked polymers, which contain no drug themselves, are described. They rapidly take up skin interstitial fluid upon skin insertion to form continuous, unblockable, hydrogel conduits from attached patch-type drug reservoirs to the dermal microcirculation. Importantly, such microneedles, which can be fabricated in a wide range of patch sizes and microneedle geometries, can be easily sterilized, resist hole closure while in place, and are removed completely intact from the skin. Delivery of macromolecules is no longer limited to what can be loaded into the microneedles themselves and transdermal drug delivery is now controlled by the crosslink density of the hydrogel system rather than the stratum corneum, while electrically modulated delivery is also a unique feature. This technology has the potential to overcome the limitations of conventional microneedle designs and greatly increase the range of the type of drug that is deliverable transdermally, with ensuing benefits for industry, healthcare providers and, ultimately, patients.
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Affiliation(s)
- Ryan F Donnelly
- School of Pharmacy, Queens University Belfast 97 Lisburn Road, Belfast BT9 7BL, UK
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16
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Zhai H, Meier-Davis SR, Cayme B, Shudo J, Maibach H. Irritant contact dermatitis: effect of age. Cutan Ocul Toxicol 2011; 31:138-43. [PMID: 21967594 DOI: 10.3109/15569527.2011.618472] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Knowledge on age-relationship to irritant contact dermatitis (ICD) remains of interest. We searched for articles and textbooks on age-relationship to ICD and evaluated relevant data. Irritant response may be enhanced in children and decline with increasing age. In general, older skin reacts more slowly and with less intensity to irritants when compared with young skin. Such age-related changes may depend: (i) on differences in percutaneous penetration in old and young skin, and/or on (ii) differences in the microcirculatory efficiency, which serves as the route by which inflammatory cells make their way to the site of inflammation. Additionally, stratum corneum turnover time increases with age which means that an irritant remains longer on the skin; a compromised cutaneous blood vessel network with ageing may lead to a decreased inflammatory response, decreased absorption and decreased clearance. In conclusion, age-related differences of ICD are present despite some conflicting data. Investigations elucidating this interesting subject may benefit in prevention and intervention strategies.
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Affiliation(s)
- Hongbo Zhai
- University of California, Department of Dermatology, 90, Medical Center Way, Box 0989, San Francisco, CA 94143-0989, USA.
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Berardesca E, Abril E, Serio M, Cameli N. Effects of topical gluco-oligosaccharide and collagen tripeptide F in the treatment of sensitive atopic skin. Int J Cosmet Sci 2009; 31:271-7. [DOI: 10.1111/j.1468-2494.2009.00495.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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19
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20
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Wilfong ER, Jederberg WW, Arfsten DP, Johnson EW, Thitoff AR, Brinkley WW, Schaeffer DJ. Effects of Subchronic Dermal Application of Break-Free CLP® in CD-1 Mice. Cutan Ocul Toxicol 2008. [DOI: 10.1081/cus-200068635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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21
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Augustin C, Collombel C, Damour O. Use of Dermal Equivalent and Skin Equivalent Models for in Vitro Cutaneous Irritation Testing of Cosmetic Products: Comparison with in Vivo Human Data. ACTA ACUST UNITED AC 2008. [DOI: 10.3109/15569529809049300] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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22
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23
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24
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Williamson L, Hunziker T, Suter MM, Müller EJ. Nuclear c-Myc: A Molecular Marker for Early Stage Pemphigus Vulgaris. J Invest Dermatol 2007; 127:1549-55. [PMID: 17315040 DOI: 10.1038/sj.jid.5700735] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Osborne NJ, Shaw GR, Webb PM. Health effects of recreational exposure to Moreton Bay, Australia waters during a Lyngbya majuscula bloom. ENVIRONMENT INTERNATIONAL 2007; 33:309-14. [PMID: 17169427 DOI: 10.1016/j.envint.2006.10.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 10/28/2006] [Accepted: 10/31/2006] [Indexed: 05/13/2023]
Abstract
A survey of residents in an area subject to annual toxic cyanobacterial blooms was undertaken to examine potential health effects of cyanobacteria toxins. The survey assessed the health of marine recreational water users in Deception Bay/Bribie Island area in northern Moreton Bay, Queensland, which is exposed to blooms of the nuisance and potentially harmful cyanobacterium Lyngbya majuscula. A postal survey was mailed to 5000 residents with a response rate of 27%. High numbers of people (78%) responding to the survey reported recreational water activity in Moreton Bay. Of those having marine recreational water activity, 34% reported at least one symptom after exposure to marine waters, with skin itching the most reported (23%). Younger participants had greater water exposure and symptoms than older participants. Participants with greater exposures were more likely to have skin and eye symptoms than less exposed groups, suggesting agents in the marine environment may have contributed to these symptoms. Of those entering Moreton Bay waters 29 (2.7%) reported severe skin symptoms, 12 of whom attended a health professional. Six (0.6%) reported the classic symptoms of recreational water exposure to L. majuscula, severe skin symptoms in the inguinal region. Participants with knowledge of L. majuscula were less likely to report less skin, gastrointestinal and fever and headache symptoms. In conclusion, high numbers of participants reported symptoms after exposure to waters subject to L. majuscula blooms but only a small number appeared to be serious in nature suggesting limited exposure to toxins.
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Affiliation(s)
- N J Osborne
- School of Population Health, University of Queensland, Brisbane, Queensland, Australia.
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Astner S, González S, Gonzalez E. Noninvasive evaluation of allergic and irritant contact dermatitis by in vivo reflectance confocal microscopy. Dermatitis 2007; 17:182-91. [PMID: 17150167 DOI: 10.2310/6620.2006.05052] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The clinical differentiation of allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) is often difficult to accomplish. Reflectance-mode confocal microscopy (RCM) is an imaging technique that has previously been used to examine ACD and ICD noninvasively in vivo. OBJECTIVE To determine characteristic features of ACD and ICD and their kinetic evolution over time. Ethnic susceptibility to contact irritants such as sodium lauryl sulfate and Ivory dishwashing liquid was evaluated noninvasively, and the sensitivity and specificity of RCM parameters were analyzed in a clinical context and in reference to patch testing. METHODS Subjects were patch-tested with allergens, irritants, and controls. Clinical scoring and RCM evaluation were performed at various time points, assessing stratum corneum (SC) disruption, spongiosis, exocytosis, vesicle formation, and epidermal thickness. RESULTS RCM features of both ACD and ICD include spongiosis, exocytosis, vesicle formation, and blood vessel dilatation. SC disruption, epidermal necrosis, and hyperproliferation are hallmarks of ICD whereas ACD more typically presents with vesicle formation. Patients with ICD showed a more rapid recovery than those with ACD. When tested with Ivory soap at selected concentrations, Caucasians, when compared to African Americans, showed significantly lower clinical thresholds for ICD and features that were more severe. CONCLUSIONS RCM may be a promising new technology for longitudinal noninvasive studies of contact dermatitis (CD). Using a diagnostic algorithm and those parameters with high sensitivity for CD, RCM may facilitate the differentiation of acute ACD and ICD. RCM can reliably visualize cutaneous changes at subclinical degrees of CD, which suggests a possible role for RCM as an adjunctive tool in CD diagnosis. The results of this pilot study also indicate ethnic differences in the response to contact irritants. However, further studies are needed to substantiate the relevance and clinical applicability of our findings.
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Affiliation(s)
- Susanne Astner
- Department of Dermatology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
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Kawahara K, Tojo K. Skin Irritation in Transdermal Drug Delivery Systems: A Strategy for its Reduction. Pharm Res 2006; 24:399-408. [PMID: 17191093 DOI: 10.1007/s11095-006-9165-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Accepted: 09/11/2006] [Indexed: 11/30/2022]
Abstract
PURPOSE Active pharmaceutical ingredients (API) in transdermal drug delivery systems (TDS) often causes skin irritation such as erythema and edema. We have studied a possible approach for the reduction of skin irritation by patch formulations that control the rates of skin permeation and elimination of API. METHODS Loxoprofen (LX-base) was used to induce the skin irritation. The redness value (Deltaa) was evaluated as a measure of erythema by Chroma Meter. The in vitro skin permeation and release profiles were also investigated by using a side-by-side diffusion cell. RESULTS The redness values were not correlated either with the cumulative amount of API permeated or the concentration of LX-base in the skin, but well correlated with the elimination rate of LX-base from the skin after the removal of the formulation. The formulation with gradual decrease of permeation rate during application accelerated the elimination rate after application, and resulted in the reduction of the skin irritation. CONCLUSIONS The skin pharmacokinetics of API, not only permeation during application but also release after the patch removal, was found to be a significant factor for skin irritation. To minimize the skin irritation, it's also important to eliminate the residual API in the skin promptly after application.
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Affiliation(s)
- Koji Kawahara
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4, Kawazu, Iizuka, Fukuoka, 820-8502, Japan.
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de Souza RCA, Cunha JM, Ferreira SH, Cunha FQ, Lima HC. Different inflammatory mediators induce inflammation and pain after application of liquid nitrogen to the skin. Cryobiology 2006; 53:319-29. [PMID: 17005173 DOI: 10.1016/j.cryobiol.2006.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2005] [Revised: 12/02/2005] [Accepted: 08/08/2006] [Indexed: 11/28/2022]
Abstract
The application of liquid nitrogen to the skin induces inflammation and pain. However, there is little data on the role of inflammatory mediators in the production of these symptoms. We have developed an experimental model to study some aspects of the inflammatory response and its mediators following the application of cold. We have applied liquid nitrogen jets to subcutaneous air pouches in the dorsal skin of rats to study the kinetics of the migration of inflammatory cells; also to the ear for histopathological analysis and on the paws for edema and pain. Inflammatory mediators were identified by pharmacological means. The results showed that the cellular inflammatory response was characterized by persistent cell migration, mainly of granulocytes. Histopathology of the ears confirmed these findings. Histamine and sympathomimetic mediators were mainly responsible for the resultant swelling. However, the hypernociception that resulted involved other mediators including IL-1 and eicosanoids. These data suggest that interference with the release of inflammatory mediators might reduce the side effects of cryosurgery and prevent hyperalgesia and inflammation at the site of application of cold.
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Belsito DV. Occupational contact dermatitis: etiology, prevalence, and resultant impairment/disability. J Am Acad Dermatol 2006; 53:303-13. [PMID: 16021126 DOI: 10.1016/j.jaad.2005.02.045] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cutaneous irritant and allergic responses account for the vast majority of cases of occupational contact dermatitis (OCD). Although the pathophysiologic responses to these two different exposures are distinct, the clinical differentiation between chronic cumulative irritant contact dermatitis and allergic contact dermatitis can be difficult and frequently requires patch testing. This article reviews the recommended algorithms that clinicians should utilize to assess whether a worker suffers from OCD. The prevalence of OCD, its predisposing factors (both endogenous and exogenous), and prognosis are discussed in depth. Finally, issues surrounding the assessment of impairment and disability resulting from OCD are summarized.
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Affiliation(s)
- Donald V Belsito
- Division of Dermatology, University of Kansas Medical Center, Kansas City, Kansas 66160-7319, USA.
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Astner S, Burnett N, Rius-Díaz F, Doukas AG, González S, Gonzalez E. Irritant contact dermatitis induced by a common household irritant: A noninvasive evaluation of ethnic variability in skin response. J Am Acad Dermatol 2006; 54:458-65. [PMID: 16488297 DOI: 10.1016/j.jaad.2005.11.1099] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 11/16/2005] [Accepted: 11/30/2005] [Indexed: 11/28/2022]
Abstract
OBJECTIVE This study was undertaken to investigate the ethnic susceptibility to irritant contact dermatitis induced by a common dishwashing liquid using noninvasive technologies. METHODS A total of 30 participants (15 Caucasian, 15 African American) were patch tested to graded concentrations of a common household irritant and evaluated using clinical scoring, reflectance confocal microscopy, transepidermal water loss, and fluorescence excitation spectroscopy. RESULTS At 24 hours, the concentration thresholds for clinically perceptible irritancy were significantly higher for African American compared with Caucasian participants. Reflectance confocal microscopy showed stratum corneum disruption, parakeratosis, and spongiosis; these features were more severe in Caucasian participants (P < or = .002). Mean values for transepidermal water loss were significantly higher in the Caucasian group at comparable clinical scores (P < or = .005). Fluorescence excitation spectroscopy showed a broad excitation band at 300 nm (emission 340 nm) and values in both groups returned to baseline by day 7. LIMITATIONS This pilot study was limited in scope and larger studies are needed to further evaluate ethnic differences in irritant contact dermatitis and to demonstrate the applicability of our findings for other irritants. CONCLUSION Clinical evaluation, reflectance confocal microscopy, and transepidermal water loss showed significant differences in the cutaneous irritant response between both groups suggesting a superior barrier function of African American skin. Fluorescence excitation spectroscopy on the other hand demonstrated no differences in the hyperproliferative response after irritant exposure and indicated similar kinetics for the two groups.
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Affiliation(s)
- Susanne Astner
- Wellman Center for Photomedicine, Department of Dermatology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Kano S, Sugibayashi K. Kinetic Analysis on the Skin Disposition of Cytotoxicity as an Index of Skin Irritation Produced by Cetylpyridinium Chloride: Comparison of In Vitro Data using a Three-Dimensional Cultured Human Skin Model with In Vivo Results in Hairless Mice. Pharm Res 2006; 23:329-35. [PMID: 16477395 DOI: 10.1007/s11095-006-9141-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2005] [Accepted: 10/19/2005] [Indexed: 11/27/2022]
Abstract
PURPOSE The aim of this study was to kinetically and dynamically analyze in vitro cytotoxicity as an index of skin irritation by use of a three-dimensional cultured human skin model and to compare the in vitro assay data with data from living animals. METHODS A cationic surfactant, cetylpyridinium chloride (CPC), was selected as a model irritant. Living skin equivalent-high (LSE-high) and hairless mice were used for the in vitro and in vivo tests, respectively. Skin irritation dermatodynamics was evaluated by calorimetric thiazoyl blue (MTT) conversion assay both for in vitro and in vivo tests, whereas dermatokinetics of CPC in LSE-high and mouse skin were evaluated using HPLC. RESULTS The time course of cell viability in the skin after application of CPC to intact skin was distinctly different from that of stratum-corneum-stripped skin in both LSE-high and hairless mice. Biphasic behavior characterized by two first-order rates with an inflection time point was observed in intact skin, whereas cell viability monoexponentially decreased immediately after CPC application in stripped skin. The time courses of cell viability in the skin and dermatodynamics were closely related to that of dermatokinetics of CPC. CONCLUSION The present study demonstrates that the in vitro cytotoxic profile was similar to the in vivo cytotoxicity test and that dermatodynamics was related to dermatokinetics of CPC.
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Affiliation(s)
- Satoshi Kano
- Faculty of Pharmaceutical Sciences, Josai University, 1-1, Keyakidai, Sakado, Saitama 350-0295, Japan
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Abstract
Dermatitis is a common problem both in the workplace and in the general community. Airline personnel represent a novel occupational group as they are also exposed to a wide range of potential chemical irritants and other aggravating factors, such as low relative humidity and airborne pollutants. Common skin irritants include dielectric fluids from electrodischarge machining, 'prepreg' materials and sealants in aircraft manufacture, kerosene and various jet-fuel components. Commercial jet fuel is a complex mixture of aliphatic and aromatic compounds, and there is potential for dermal exposure among refueling and maintenance crew. Low relative humidity appears to exacerbate dermatitis amongst aircrew, especially on longer flight durations. Pilots may also be exposed to additional skin irritants outside of the cabin environment, such as ethylene glycol, hydraulic fluid or jet fuel, all of which may be encountered during routine inspections of aircraft before and after flight. Given these factors, preventive measures must carefully consider the undoubted potential for contact with irritants and allergens, which may lead to dermatitis in airline personnel.
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Affiliation(s)
- Peter A Leggat
- School of Public Health and Tropical Medicine, James Cook University, Townsville, Australia.
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Welss T, Basketter DA, Schröder KR. In vitro skin irritation: facts and future. State of the art review of mechanisms and models. Toxicol In Vitro 2005; 18:231-43. [PMID: 15046769 DOI: 10.1016/j.tiv.2003.09.009] [Citation(s) in RCA: 177] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2003] [Accepted: 09/19/2003] [Indexed: 11/27/2022]
Abstract
The skin is the main target tissue for exogenous noxes, protecting us from harmful environmental hazards, UV-irradiation and endogenous water loss. It is composed of three layers, whereas the outermost epidermis is a squamous epithelium that mainly consists of keratinocytes. These cells execute a terminal differentiation, which finally results in the assembly of the stratum corneum. This layer, consisting of cornified keratinocytes, is an effective barrier against a vast number of substances. Apart of this, keratinocytes play crucial roles in the immune surveillance and the initiation, modulation and regulation of inflammation in the epidermis. Regarding cutaneous inflammatory reactions, skin irritation is one of the most common adverse effect in humans. For reasons of human safety assessment new chemicals are still evaluated for irritant potentials by application to animals followed by visible changes such as erythema and oedema. Testing for skin irritation in animals potentially cause them pain and discomfort. Furthermore, the results are not always predictive for those found in humans. In order to replace animal testing and to improve the prediction of irritants, the cosmetic and toiletry industry, in Europe represented by Colipa, develops and uses several alternative in vitro test systems. In this respect, the use of in vitro reconstructed organotypic skin equivalents are mostly favored, because of their increasingly close resemblance to human skin. Due to ethical and scientific questions and on account of the 7th amendment of the European Council Directive 76/768/EEC, the authors see the requirement to drive the development of alternative tests for irritants. Therefore, this article centres on cosmetic ingredients and provides the readership an overview of the state of art of cellular mechanisms of skin irritation and summarizes the results of the commonly used skin equivalents to evaluate irritation in vitro.
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Affiliation(s)
- Thomas Welss
- VTB-Skin Biochemistry, Henkel KGaA, Building Z33, Henkelstrasse 67, D-40191, Duesseldorf, Germany.
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Issa Y, Brunton PA, Glenny AM, Duxbury AJ. Healing of oral lichenoid lesions after replacing amalgam restorations: a systematic review. ACTA ACUST UNITED AC 2004; 98:553-65. [PMID: 15529127 DOI: 10.1016/j.tripleo.2003.12.027] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE We sought to systematically review the literature related to oral lichenoid lesions (OLLs) and amalgam restorations. STUDY DESIGN Cohort and case-controlled studies (no randomized controlled trials or controlled clinical trials available) were reviewed with respect to inclusion criteria and data on patients with OLLs, treatment interventions, and the measurement of outcomes. RESULTS Fourteen cohort and 5 case-controlled trials met the criteria. The study population consisted of 1158 patients (27% male and 73% female; age range, 23-79 years). From 16% to 91% of patients had positive patch test results for at least 1 mercury compound. Of 1158 patients, 636 had to have their restorations replaced. The follow-up period ranged from 2 months to 9 1/2 years. Complete healing ranged from 37.5% to 100%. The greatest improvements were seen in lesions in close contact with amalgam. CONCLUSIONS Protocols must be standardized to obtain valid results. The replacement of amalgam restorations can result in the resolution or improvement of OLLs. Patch testing seems to be of limited value. The topographic relationship between an OLL and an amalgam restoration is a useful--but not conclusive--marker.
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Affiliation(s)
- Y Issa
- University Dental Hospital of Manchester, England, UK
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Swindells K, Burnett N, Rius-Diaz F, González E, Mihm MC, González S. Reflectance confocal microscopy may differentiate acute allergic and irritant contact dermatitis in vivo. J Am Acad Dermatol 2004; 50:220-8. [PMID: 14726876 DOI: 10.1016/j.jaad.2003.08.005] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Acute irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD) may be difficult to distinguish by clinical or histologic assessment. Reflectance confocal microscopy (RCM) enables real-time, high-resolution skin imaging in vivo. OBJECTIVE We sought to image, characterize, and distinguish acute ACD and ICD in vivo. METHODS Volunteers with ACD were patch tested with an allergen and the irritant, sodium lauryl sulfate. RCM imaging and transepidermal water loss measurements were performed at 24 and 72 hours. Biopsy specimens were correlated with RCM images. RESULTS Spongiosis, epidermal inflammatory cell infiltrate, and vesicle formation were observed in ACD and ICD. Compared with ACD, ICD showed greater disruption of the stratum corneum, and more parakeratosis. There was a significantly greater increase in transepidermal water loss for ICD compared with ACD. CONCLUSION RCM is a promising tool for dynamic, noninvasive assessment and may help to differentiate acute ACD and sodium lauryl sulfate-induced ICD.
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Affiliation(s)
- Kirsty Swindells
- Wellman Laboratories of Photomedicine, Massachusetts Geneeral Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
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Corsini E, Viviani B, Zancanella O, Lucchi L, Visioli F, Serrero G, Bartesaghi S, Galli CL, Marinovich M. Induction of adipose differentiation related protein and neutral lipid droplet accumulation in keratinocytes by skin irritants. J Invest Dermatol 2003; 121:337-44. [PMID: 12880426 DOI: 10.1046/j.1523-1747.2003.12371.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Keratinocytes play an important role in skin irritation. In an attempt to investigate mechanistic bases of human skin irritation response, we recently identified the upregulation by skin irritants of adipose differentiation related protein (ADRP) in reconstituted human epidermis. ADRP is a lipid-storage-droplet-associated protein, governing deposition and release of lipids from droplets. The purpose of this study was to characterize, in a human keratinocyte cell line (NCTC 2544), sodium-dodecyl-sulfate-induced ADRP expression, to identify the biochemical events that lead to ADRP expression, and to understand its function in sodium dodecyl sulfate cytotoxicity. Sodium dodecyl sulfate induced a concentration- and time-related production of ADRP that was associated with lipid droplet accumulation. Lipid accumulation following sodium dodecyl sulfate treatment was due to intracellular redistribution rather than lipid neosynthesis, as indicated by equivalent 14C-oleate and 14C-acetate incorporations. Other skin irritants, namely benzalkonium chloride, tributyltin, and 12-O-tetradecanoylphorbol 13-acetate, also induce lipid droplet accumulation. Sodium-dodecyl-sulfate-induced ADRP expression and lipid droplet accumulation were modulated by the calcium chelator BAPTA, indicating a role of calcium in ADRP induction. Decrease of sodium-dodecyl-sulfate-induced ADRP expression by specific ADRP antisense oligonucleotide resulted in increased cytotoxicity, indicating a protective role of ADRP and lipid accumulation in the process of cell damage induced by skin irritants. ADRP expression was also induced in vivo following treatment with sodium dodecyl sulfate in an experimental model of skin irritation, indicating that the in vitro model represents irritation.
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Affiliation(s)
- Emmanuela Corsini
- Laboratory of Toxicology, Department of Pharmacological Sciences, University of Milan, Italy.
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Abstract
Skin reactions are common in the workplace. The skin, which constantly is exposed to chemicals and industrial processes, develops inflammatory reactions, most commonly dermatitis, which may have an allergic or irritant basis. The epidemiology, pathophysiology, and clinical features of common occupational dermatoses are discussed. Irritant, allergic, and urticarial contact reactions are compared, and their clinical features are outlined. Important occupational irritants and allergens, their sources, and the industries in which they most commonly are found are listed. The prognosis and therapy of these occupational reactions are examined.
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Affiliation(s)
- Marc Antezana
- Department of Dermatology, Oregon Health and Science University, 3181 South West Sam Jackson Park Road, OP06, Portland, OR 97201-3098, USA
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Hachem JP, De Paepe K, Sterckx G, Kaufman L, Rogiers V, Roseeuw D. Evaluation of biophysical and clinical parameters of skin barrier function among hospital workers. Contact Dermatitis 2002; 46:220-3. [PMID: 12081700 DOI: 10.1034/j.1600-0536.2002.460406.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The goal of this study was to evaluate biophysically and clinically the hand skin of nurses working in the operating room in comparison with the hand skin of a control group of female administrative employees. 19 nurses and 14 employees were included in this trial. Transepidermal water loss (TEWL) and stratum corneum (SC) hydration were evaluated on 4 different test sites - dominant and non-dominant pulse, and dominant and non-dominant hand dorsum. The clinical score Dermatology Life Quality Index (DLQI) and subjective evaluation of skin sensitivity were also recorded. In comparison with the control group, TEWL values among nurses were significantly higher on all test sites, while SC hydration was significantly lower on 3 of the 4 test sites. In addition, clinical score showed the presence of irritant contact dermatitis (ICD). DLQI reported a higher level of disability among the nurses group, while the subjective evaluation of skin sensitivity was identical in both groups. The results suggest the presence of skin barrier alterations and clinical signs of chronic ICD on the hands of nurses working in operating room units.
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Affiliation(s)
- Jean Pierre Hachem
- Department of Dermatology, Vrije Universiteit Brussel, B-1090 Brussels, Belgium
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Fluhr JW, Kuss O, Diepgen T, Lazzerini S, Pelosi A, Gloor M, Berardesca E. Testing for irritation with a multifactorial approach: comparison of eight non-invasive measuring techniques on five different irritation types. Br J Dermatol 2001; 145:696-703. [PMID: 11736891 DOI: 10.1046/j.1365-2133.2001.04431.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Non-invasive bioengineering methods are widely used in the assessment of irritant skin reactions. OBJECTIVES To assess the ability of eight non-invasive measurement techniques to distinguish changes in skin conditions over time, these changes being induced by five different irritants. METHODS The following techniques were compared in a multivariate analysis: laser-Doppler perfusion imaging (LDI), laser-Doppler flowmetry (LDF), transepidermal water loss (TEWL), visual scoring (VS), colorimetric measurements (Chromameter CR 200 a* and L* scales), Mexameter Hb scale (Mexa Hb) and capacitance (Corneometer CM 820). Irritants tested were sodium lauryl sulphate 2% (SLS), tape stripping (TS), tretinoin 0.05% (TRET), ultraviolet (UV) exposure to 30 W m(-2) UVB/95 W m(-2) UVA, and dithranol 0.5% (DIT). Measurements were performed at baseline and after 24, 48 and 72 h. The study was conducted on the upper back of 11 healthy volunteers of both sexes aged 27-51 years. RESULTS For DIT it was possible to discriminate over time with CR 200 a* and L*, VS, LDI, LDF and Mexa Hb. In SLS discrimination over time was seen with TEWL and LDF. Discrimination in TS was demonstrated for TEWL, VS, CR 200 a*, CM 820, LDF, LDI and Mexa Hb. In TRET discrimination ability was seen for LDI, LDF, Mexa Hb and VS. For UV it was possible to discriminate using VS, TEWL, LDF, LDI and Mexa Hb. CONCLUSIONS Different irritation patterns need different measurement modalities in order to give optimal discrimination over time.
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Affiliation(s)
- J W Fluhr
- Department of Dermatology, University of Pavia, IRCCS Policlinico San Mateo, 27100 Pavia, Italy.
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Arroyo CM, Broomfield CA, Hackley BE. The role of interleukin-6 (IL-6) in human sulfur mustard (HD) toxicology. Int J Toxicol 2001; 20:281-96. [PMID: 11766126 DOI: 10.1080/109158101753253027] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The authors applied in vitro models of controlled damage to human epidermal keratinocytes (HEKs), human skin fibroblasts (HSFs), and human breast skin tissue (HBST) to examine the mechanism responsible for sulfur mustard (HD)-induced interleukin-6 (IL-6) alterations. Treatment with 100 microM HD for 24 hours resulted in a significant increased amount of IL-6 being secreted by HEKs (HD-exposed to control ratio [E/C] = 4.15 +/- 0.07) and by HSFs (E/C = 7.66 +/- 0.04). Furthermore, the HD-induced secretion of IL-6 in HEKs was neutralized with monoclonal human IL-6 antibodies. The secretion of IL-6 in HBST supernatant exposed to HD produced conflicting results. Although an increase of IL-6 was observed in control superfusion media from HBST, IL-6 levels were observed to decrease as the concentration of HD increased. Time course of IL-6 mRNA levels were performed using a competitive polymerase chain reaction (PCR) and human IL-6 mRNA assay detection kit in control and HD (100 microM)-treated HEKs cells. IL-6 mRNA transcripts in HD-exposed HEKs were first observed within 2 hours, dropped at 5 to 6 hours, and increased by approximately 2.2-fold and 8.5-fold at 24 to 48 hours after HD exposure, respectively, as detected by the Xplore mRNA Quantification System. Surface-enhanced laser desorption ionization (SELDI) mass spectrometry was also applied to study the secretion pattern of IL-6 on lysate preparations of HBST. A peak in the area of 23,194 to 23,226 Da was detected using antibody coupled to the chip. This peak was assigned to correspond to the mass of the IL-6 glycoprotein. Recombinant human IL-6 (rhIL-6) exposed to HD lacked the second disulfide bridge and was partially unfolded, as determined by nuclear magnetic resonance-nuclear Overhauser enhancement and exchange spectroscopy (NMR-NOESY). The disappearance of the resonance peak at 3.54 ppm and the appearance of a new chemical shift at 1.85 ppm suggested that a change in structure had occurred in the presence of HD. From the data, the possibility cannot be excluded that IL-6 might be involved in the early event of structural changes of the signal transducer glycoprotein that indirectly initiates the cascade of events such as skin irritation and blister formation observed in the pathophysiology of HD injury.
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Affiliation(s)
- C M Arroyo
- Drug Assessment Division, US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, Maryland 21010-5400, USA.
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Moon SH, Seo KI, Han WS, Suh DH, Cho KH, Kim JJ, Eun HC. Pathological findings in cumulative irritation induced by SLS and croton oil in hairless mice. Contact Dermatitis 2001; 44:240-5. [PMID: 11260241 DOI: 10.1034/j.1600-0536.2001.044004240.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
It is known that the pathological features of acute irritant contact dermatitis are specific according to the irritant. However, in chronic irritant contact dermatitis, it is not clear whether specific patterns exist. To investigate whether the specific pathology of acute irritant contact dermatitis is sustained in chronic irritant contact dermatitis, sodium lauryl sulfate (SLS) and croton oil were applied 3x a week for 2 weeks on the dorsal skin of hairless mice using Finn Chambers. The pathologic changes induced by irritants at various concentrations were evaluated using H&E and Luna's staining, as well as immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU), keratin 6 and loricrin. Our results showed that epidermal hyperplasia and inflammatory infiltration were relatively marked in the groups treated with higher concentrations of irritants. These features were more prominent in the 1% croton oil treated group than in the 0.25% SLS treated group. However, lower concentrations of irritants resulted in very similar histological changes, characterized by epidermal hyperplasia with minimal inflammatory infiltration, irrespective of the chemical. Our results suggest that the histological responses to irritants vary with concentration in cumulative irritation, as in acute irritation, but repetitive mild irritation may evoke common histological changes, characterized by epidermal hyperplasia with minimal inflammatory infiltration, irrespective of the chemical used.
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Affiliation(s)
- S H Moon
- Department of Dermatology, Seoul National University College of Medicine, 28 Yungun-Dong, Chongno-Gu, Seoul 110-744, Korea
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Uter W, Geier J, Land M, Pfahlberg A, Gefeller O, Schnuch A. Another look at seasonal variation in patch test results. A multifactorial analysis of surveillance data of the IVDK. Information Network of Departments of Dermatology. Contact Dermatitis 2001; 44:146-52. [PMID: 11217986 DOI: 10.1034/j.1600-0536.2001.044003146.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
There is conflicting evidence concerning seasonal variability of patch test results and no evidence concerning the influence of season on weak-positive, possibly false-positive, irritant reactions, which was analysed in the present study. Data collected in the German Information Network of Departments of Dermatology (IVDK) 1992 to 1997 were combined with external environmental data on temperature and absolute humidity in Germany, and bivariate as well as logistic regression analyses performed concerning the association between reactivity to selected allergens and air temperature and absolute humidity on the respective days of patch testing. Between 39,239 and 41,629 patients had been tested with the 4 allergens considered here. Only formaldehyde exhibited a distinct increase in questionable or irritant as well as weak-positive reactions associated with dry, cold weather. Methylchloroisothiazolinone/methylisothiazolinone and lanolin alcohol showed only a weak, and epoxy resin no, association with climatic conditions. The results indicate that weak-positive reactions, at least to formaldehyde as a prototype of an allergen which is at the same time a marginal irritant, may sometimes be irritant rather than allergic. Patients showing these should be re-tested to improve the poor reproducibilty observed with this allergen.
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Affiliation(s)
- W Uter
- Information Network of Department of Dermatology IVDK, University of Göttingen, Germany
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44
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Newby CS, Barr RM, Greaves MW, Mallet AI. Cytokine release and cytotoxicity in human keratinocytes and fibroblasts induced by phenols and sodium dodecyl sulfate. J Invest Dermatol 2000; 115:292-8. [PMID: 10951249 DOI: 10.1046/j.1523-1747.2000.00056.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phenolic compounds used in pharmaceutical and industrial products can cause irritant contact dermatitis. We studied the effects of resorcinol, phenol, 3,5-xylenol, chloroxylenol, and 4-hexyl-resorcinol on normal human epidermal keratinocytes and dermal fibroblasts for cytotoxicity and cytokine release, determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide methodology and enzyme-linked immunosorbent assay, respectively. An inverse correlation between phenol concentrations causing a 50% reduction in keratinocyte and fibroblast viability at 24 h and their octanol water-partition coefficients (i.e., hydrophobicity) was observed. 3,5-xylenol, chloroxylenol, hexyl-resorcinol, and sodium dodecyl sulfate, but not resorcinol or phenol, induced release of interleukin-1alpha from keratinocytes at cytotoxic concentrations. Variable release of tumor necrosis factor-alpha and interleukin-8 from keratinocytes occurred only at toxic threshold concentrations of the phenols or sodium dodecyl sulfate. Subtoxic concentrations of phenols or sodium dodecyl sulfate did not induce cytokine release from keratinocytes. Neither the phenols nor sodium dodecyl sulfate induced release of the chemokines interleukin-8, growth-related oncogene-alpha or monocyte chemotactic protein-1 from fibroblasts. Conditioned media from keratinocytes treated with cytotoxic concentrations of 3,5-xylenol, chloroxylenol, hexyl-resorcinol, or sodium dodecyl sulfate stimulated further release of the chemokines from fibroblasts above that obtained with control media. Rabbit anti-interleukin-1alpha serum inhibited keratinocyte-conditioned media induction of chemokine release. We have shown a structure-cytotoxicity relationship for a series of phenols as well as an association of interleukin-1alpha release with a cytotoxic effect. We demonstrated a cytokine cascade amplification step by the actions of stimulated keratinocyte media on cultured dermal fibroblasts, identifying interleukin-1alpha as the principal initiator of chemokine synthesis.
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Affiliation(s)
- C S Newby
- St John's Institute of Dermatology, Guy's, King's and St Thomas' School of Medicine, King's College London, St Thomas' Hospital, London, U.K
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Abstract
Skin irritation is a complex phenomenon that involves resident epidermal cells, fibroblasts of dermis, and endothelial cells as well as invading leukocytes interacting with each other under the control of a network of cytokines and lipid mediators. Keratinocytes play an important role in the initiation and perpetuation of skin inflammatory reactions through the release of, and responses to cytokines. While resting keratinocytes produce some cytokines constitutively, a variety of environmental stimuli, such as tumor promoters, ultraviolet light and chemical agents, can induce epidermal keratinocytes to release inflammatory cytokines (IL-1, TNF-alpha), chemotactic cytokines (IL-8, IP-10), growth promoting cytokines (IL-6, IL-7, IL-15, GM-CSF, TGF-alpha) and cytokines regulating humoral vs. cellular immunity (IL-10, IL-12, IL-18). The role of cytokines in xenobiotics-induced skin irritation and the early molecular events that follow the treatment with irritant compounds will be discussed.
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Affiliation(s)
- E Corsini
- Center for Cosmetic Toxicology, Institute of Pharmacological Sciences, University of Milan, Italy.
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46
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Forsey RJ, Shahidullah H, Sands C, McVittie E, Aldridge RD, Hunter JA, Howie SE. Epidermal Langerhans cell apoptosis is induced in vivo by nonanoic acid but not by sodium lauryl sulphate. Br J Dermatol 1998; 139:453-61. [PMID: 9767290 DOI: 10.1046/j.1365-2133.1998.02409.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Exposure to irritants may cause chronic irritant contact dermatitis (ICD), characterized by irregular epidermal thickening and a predominantly dermal mononuclear cell infiltrate. The mechanisms involved, and why only certain individuals are affected, are not clearly understood. Different irritants may trigger different cellular and molecular interactions between resident skin cells and recruited inflammatory cells. In some individuals these interactions may become self-perpetuating resulting in persistent inflammation in the absence of continued exposure. This study examined Langerhans cell (LC) density in clinically normal skin of 46 patients with chronic ICD and 10 healthy individuals, and compared the action of the two irritants nonanoic acid (NA) and sodium lauryl sulphate (SLS) on the LCs and keratinocytes of clinically normal skin in patients with chronic ICD. There was a higher number of LCs/mm basement membrane in patients compared with controls, although there was no difference in the number of dendrites/LC nor in dendrite length. SLS induced keratinocyte proliferation after 48 h exposure, had no effect on LC number or distribution, and induced keratinocyte apoptosis after 24 and 48 h exposure. In contrast, NA decreased keratinocyte proliferation after 24 h exposure but this returned to basal levels after 48 h, and induced epidermal cell apoptosis after only 6 h exposure. NA dramatically decreased LC number after 24 and 48 h exposure, which was accompanied by basal redistribution and decreased dendrite length. Most significantly, NA induced apoptosis in over half of the LCs present after 24 and 48 h exposure.
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Affiliation(s)
- R J Forsey
- Department of Pathology, Edinburgh University Medical School, Teviot Place, Edinburgh EH8 9AG, U.K.; Department of Dermatology, Edinburgh University Medical School, Teviot Place, Edinburgh EH8 9AG, U.K
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47
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Li LF, Fiedler VC, Kumar R. Down-regulation of protein kinase C isoforms in irritant contact dermatitis. Contact Dermatitis 1998; 38:319-24. [PMID: 9687030 DOI: 10.1111/j.1600-0536.1998.tb05766.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein kinase C (PKC) isoforms are important in cell signal transduction associated with regulation of cell proliferation and differentiation. In this study, alterations of PKC isoform levels in irritant patch test reactions were detected by Western immunoblots. 4 chemically and structurally different irritants, 4% and 8% hydrochloric acid (HCl); 1% and 2% sodium hydroxide (NaOH); 20% and 40% nonanoic acid (NON) in 1-propanol; and 5% and 10% sodium dodecyl sulfate (SDS) were applied on the backs of mice in Finn Chambers and fixed with surgical dressings. The patches were kept on the skin for 24 h and removed. 24 h after removal, mild erythema with thickening of skin without vesicles was observed in all irritated skin, except that 4% HCl and 1% NaOH treated skin showed unremarkable skin reaction. No visible skin reaction was detected in vehicle-treated skin. PKC isoform alpha, beta, gamma, and delta levels in irritated skin revealed a 10% to 65% decrease compared to vehicle treated skin. These results indicate that in HCl, NaOH, NON and SDS-induced irritation, activation of the PKC related cell signal transduction cascade may be involved, and that PKC mediated events may be a common phenomenon in irritant contact dermatitis.
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Affiliation(s)
- L F Li
- Department of Dermatology, University of Illinois at Chicago, 60612, USA
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Abstract
Several different types of interactions are possible between a chemical, a mixture of chemicals, and associated extrinsic factors (i.e., mechanical irritation) in the oral mucosa. These interactions can be broadly classified as irritative or allergenic in nature. In each case, the pathology usually includes mucosal inflammation. The information compiled and reviewed in this article suggests that, given the broad definition of surface lesions/mucosal abnormalities, there may be a continuum of irritation that can be termed "irritant contact stomatitis." This may be due to the fact that the mouth is lined with highly vascular mucosa that turns over rapidly compared to the skin, and may or may not be covered by keratin. Some regions in the mouth are uniquely sensitive to irritants because they can penetrate through the tissue easily. Key factors involved in the potential development of irritation are: inherent irritation potential of the agent, amount of exposure (concentration, duration, and frequency), ability to penetrate the tissue, and inherent reactivity of the subject as well as other extrinsic factors. Irritation leading to oral mucosal alterations is a common occurrence caused by a wide variety of exposures and insults to the oral cavity. Various irritants such as foods, chemicals, friction, thermal/mechanical injury, metals, spices, and oral care products have been documented to cause irritant reactions in susceptible individuals, particularly if used under exaggerated exposure conditions. It is important to note that most irritation in the oral cavity tends to reverse quickly when the causative agent is removed. Oral irritation is a commonly occurring phenomenon. Thus, it is important that the clinician be aware of the clinical manifestations and etiology of the condition.
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Affiliation(s)
- C C Davis
- Regulatory and Clinical Development, The Procter & Gamble Company, Cincinnati, OH, USA.
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Affiliation(s)
- C L Goh
- National Skin Centre, Institute of Dermatology, Singapore
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50
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Henry F, Goffin V, Maibach HI, Piérard GE. Regional differences in stratum corneum reactivity to surfactants. Quantitative assessment using the corneosurfametry bioassay. Contact Dermatitis 1997; 37:271-5. [PMID: 9455629 DOI: 10.1111/j.1600-0536.1997.tb02463.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The skin does not react similarly to the presence of xenobiotics over all anatomic sites. Distinct regional differences have been described for irritancy and percutaneous absorption. The present study assesses the regional variation of stratum corneum reactivity to surfactants using the corneosurfametry bioassay. Stratum corneum was harvested from 6 body sites in 20 young adults. Corneosurfametry was performed using water, 1% SLS and a 5% soap solution. Data show that the best variable to assess regional variability in irritancy is the overall difference in corneosurfametry (ODC), comparing the effect of a given surfactant with water. The dorsal hand and volar forearm were the least reactive, the neck, forehead, back and dorsal foot the most reactive, sites. It is concluded that the corneosurfametry bioassay, through the ODC variable, is a practically noninvasive tool for the evaluation of regional variation in irritancy at the level of the stratum corneum.
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Affiliation(s)
- F Henry
- Belgian SSTC Research Center 5596, Department of Dermatopathology, University of Liège, Belgium
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