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Lin Y, Ding Y, Wu Y, Yang Y, Liu Z, Xiang L, Zhang C. The underestimated role of mitochondria in vitiligo: From oxidative stress to inflammation and cell death. Exp Dermatol 2024; 33:e14856. [PMID: 37338012 DOI: 10.1111/exd.14856] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/24/2023] [Accepted: 05/31/2023] [Indexed: 06/21/2023]
Abstract
Vitiligo is an acquired depigmentary disorder characterized by the depletion of melanocytes in the skin. Mitochondria shoulder multiple functions in cells, such as production of ATP, maintenance of redox balance, initiation of inflammation and regulation of cell death. Increasing evidence has implicated the involvement of mitochondria in the pathogenesis of vitiligo. Mitochondria alteration will cause the abnormalities of mitochondria functions mentioned above, ultimately leading to melanocyte loss through various cell death modes. Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a critical role in mitochondrial homeostasis, and the downregulation of Nrf2 in vitiligo may correlate with mitochondria damage, making both mitochondria and Nrf2 promising targets in treatment of vitiligo. In this review, we aim to discuss the alterations of mitochondria and its role in the pathogenesis of vitiligo.
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Affiliation(s)
- Yi Lin
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
| | - Yuecen Ding
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
| | - Yue Wu
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
| | - Yiwen Yang
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
| | - Ziqi Liu
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
| | - Leihong Xiang
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
| | - Chengfeng Zhang
- Department of Dermatology, Huashan Hospital Fudan University, Shanghai, China
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2
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Ogawa T, Ishitsuka Y. NRF2 in the Epidermal Pigmentary System. Biomolecules 2022; 13:biom13010020. [PMID: 36671405 PMCID: PMC9855619 DOI: 10.3390/biom13010020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 12/25/2022] Open
Abstract
Melanogenesis is a major part of the environmental responses and tissue development of the integumentary system. The balance between reduction and oxidation (redox) governs pigmentary responses, for which coordination among epidermal resident cells is indispensable. Here, we review the current understanding of melanocyte biology with a particular focus on the "master regulator" of oxidative stress responses (i.e., the Kelch-like erythroid cell-derived protein with cap'n'collar homology-associated protein 1-nuclear factor erythroid-2-related factor 2 system) and the autoimmune pigment disorder vitiligo. Our investigation revealed that the former is essential in pigmentogenesis, whereas the latter results from unbalanced redox homeostasis and/or defective intercellular communication in the interfollicular epidermis (IFE). Finally, we propose a model in which keratinocytes provide a "niche" for differentiated melanocytes and may "imprint" IFE pigmentation.
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Affiliation(s)
- Tatsuya Ogawa
- Department of Dermatology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan
| | - Yosuke Ishitsuka
- Department of Dermatology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita 565-0871, Japan
- Correspondence: ; Tel.: +81-66-879-3031; Fax: +81-66-879-3039
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Hrapovic N, Richard T, Messaraa C, Li X, Abbaspour A, Fabre S, Mavon A, Andersson B, Khmaladze I. Clinical and metagenomic profiling of hormonal acne-prone skin in different populations. J Cosmet Dermatol 2022; 21:6233-6242. [PMID: 35810346 DOI: 10.1111/jocd.15225] [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: 04/19/2022] [Revised: 07/01/2022] [Accepted: 07/07/2022] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Acne is one of the most common skin concerns of unknown etiology, often connected to the menstrual cycle in women, and possibly to the microbial profile and function. OBJECTIVE We aimed to investigate how hormonal fluctuation affects hormonal acne-prone skin in different populations in relation to skin clinical parameters and microbial profiles. METHODS We evaluated skin features by using biophysical and topographical tools. For microbial profiling, we sequenced facial skin microbiota and associated the findings with the skin clinical parameters during the different phases of the menstrual cycle. RESULTS We identified differences between and within hormonal phases in women of Chinese and Caucasian origin. Changes were discovered in transepidermal water loss (TEWL), sebum level, hydration level, and pore volume. The most abundant identifiable genera in both ethnicities were Cutibacterium, Staphylococcus, and Streptococcus, without any significant abundant differences within the menstrual cycle. Interestingly, 11 bacterial metabolic pathways were downregulated in Chinese compared to Caucasian skin during the follicular phase. The majority of these pathways were associated with skin redox balance, perhaps indicating a weaker oxidative stress response in Chinese versus Caucasian skin. Novosphingobium taxa were increased in the Chinese skin microbiome, which has been reported to protect skin from pollution-mediated oxidative stress. CONCLUSION Thus, this pilot study explored some of the clinical and metagenomic changes in acne-prone skin, and provide guidance to tailor-personalized skin care regimes during the menstrual cycle. Also, the skin redox status in acne-prone skin, provides more opportunity to tailor-personalized skin care regimes.
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Affiliation(s)
| | | | | | - Xi Li
- Oriflame Cosmetics AB, Stockholm, Sweden
| | - Afrouz Abbaspour
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Björn Andersson
- Department of Cellular and molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
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Faraj S, Kemp EH, Gawkrodger DJ. Patho-immunological mechanisms of vitiligo: the role of the innate and adaptive immunities and environmental stress factors. Clin Exp Immunol 2022; 207:27-43. [PMID: 35020865 PMCID: PMC8802175 DOI: 10.1093/cei/uxab002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 10/04/2021] [Accepted: 10/15/2021] [Indexed: 12/17/2022] Open
Abstract
Epidermal melanocyte loss in vitiligo, triggered by stresses ranging from trauma to emotional stress, chemical exposure or metabolite imbalance, to the unknown, can stimulate oxidative stress in pigment cells, which secrete damage-associated molecular patterns that then initiate innate immune responses. Antigen presentation to melanocytes leads to stimulation of autoreactive T-cell responses, with further targeting of pigment cells. Studies show a pathogenic basis for cellular stress, innate immune responses and adaptive immunity in vitiligo. Improved understanding of the aetiological mechanisms in vitiligo has already resulted in successful use of the Jak inhibitors in vitiligo. In this review, we outline the current understanding of the pathological mechanisms in vitiligo and locate loci to which therapeutic attack might be directed.
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Affiliation(s)
- Safa Faraj
- Department of Oncology and Metabolism, University of Sheffield, Sheffield, UK
| | | | - David John Gawkrodger
- Department of Infection, Immunology and Cardiovascular Disease, University of Sheffield, Sheffield, UK
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Xiong J, Yang J, Yan K, Guo J. Ginsenoside Rk1 protects human melanocytes from H 2O 2‑induced oxidative injury via regulation of the PI3K/AKT/Nrf2/HO‑1 pathway. Mol Med Rep 2021; 24:821. [PMID: 34558653 PMCID: PMC8485120 DOI: 10.3892/mmr.2021.12462] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 03/30/2021] [Indexed: 12/20/2022] Open
Abstract
Vitiligo is a cutaneous depigmentation disorder caused by melanocyte injury or aberrant functioning. Oxidative stress (OS) is considered to be a major cause of the onset and progression of vitiligo. Ginsenoside Rk1 (RK1), a major compound isolated from ginseng, has antioxidant activity. However, whether RK1 can protect melanocytes against oxidative injury remains unknown. The aim of the present study was to investigate the potential protective effect of RK1 against OS in the human PIG1 melanocyte cell line induced with hydrogen peroxide (H2O2), and to explore its underlying mechanism. PIG1 cells were pretreated with RK1 (0, 0.1, 0.2 and 0.4 mM) for 2 h followed by exposure to 1.0 mM H2O2 for 24 h. Cell viability and apoptosis were determined with Cell Counting Kit‑8 and flow cytometry assays, respectively. The activity levels of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH‑Px) were analyzed using ELISA kits. Protein expression levels, including Bax, caspase‑3, Bcl‑2, phosphorylated‑AKT, AKT, nuclear factor erythroid 2‑related factor 2 (Nrf2), heme oxygenase‑1 (HO‑1), cytosolic Nrf2 and nuclear Nrf2, were analyzed using western blot analysis. In addition, the expression and localization of Nrf2 were detected by immunofluorescence. RK1 treatment significantly improved cell viability, reduced the apoptotic rate and increased the activity levels of SOD, CAT and GSH‑Px in the PIG1 cell line exposed to H2O2. In addition, RK1 treatment notably induced Nrf2 nuclear translocation, increased the protein expression levels of Nrf2 and HO‑1, and the ratio of phosphorylated‑AKT to AKT in the PIG1 cells exposed to H2O2. Furthermore, LY294002 could reverse the protective effect of RK1 in melanocytes against oxidative injury. These data demonstrated that RK1 protected melanocytes from H2O2‑induced OS by regulating Nrf2/HO‑1 protein expression, which may provide evidence for the application of RK1 for the treatment of vitiligo.
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Affiliation(s)
- Jian Xiong
- Department of Dermatology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072, P.R. China
| | - Jianing Yang
- Department of Dermatology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072, P.R. China
| | - Kai Yan
- Department of Dermatology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610072, P.R. China
| | - Jing Guo
- Department of Dermatology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610072, P.R. China
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Effects of a Traditional Caraway Formulation on Experimental Models of Vitiligo and Mechanisms of Melanogenesis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2021; 2021:6675657. [PMID: 33959187 PMCID: PMC8075664 DOI: 10.1155/2021/6675657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 03/07/2021] [Accepted: 04/08/2021] [Indexed: 12/14/2022]
Abstract
Background Kursi Karwiya or caraway tablet (CWT), a traditional medicine formula, is widely used in Xinjiang, China, for treating vitiligo, a common autoimmune disease for which there is currently no satisfactory cure. Clinical interventions include pharmacological treatment with psoralens, often in conjunction with UVA radiation, but toxic side effects limit this application. Studies on the activities and mechanisms of CWT are scarce. Objective To investigate the in vitro and in vivo effects of CWT in B16 cell line and in animal models of vitiligo, further exploring its mechanisms of regulating melanogenesis. Methods Effects of CWT on melanin synthesis in B16 cells and mushroom tyrosinase activity were investigated in vitro. The signaling pathway of melanogenesis in murine B16 melanoma cells was examined by Western blotting. Two different animal models were used, vitiligo induced by hydroquinone in the mouse model and by hydrogen peroxide in the guinea pig model. Relevant biochemical parameters in blood and skin tissue were measured, and visual inspection, histopathology, and immunohistochemical analysis of treated areas were carried out. Results CWT produced changes in biochemical parameters including TYR, MDA, MAO, AChE, IL-6, INF-α, β-EP, and cAMP in blood and/or skin tissue and in regulating melanogenesis. After treatment with CTW, skin color, melanin containing hair follicles, and expression of TYR, TRP-1, and TRP-2 in the skin of animals were significantly affected. Conclusions CWT alleviated many of detrimental effects in both models of vitiligo. Tyrosinase activity and melanin content in B16 cells were increased, at least in part, via activation of the PKA p38 MAPK signaling pathways. Our results show that CWT produces beneficial effects on parameters of vitiligo and is worthy of further investigation for use in this distressing autoimmune disorder which currently has no effective cure.
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Abstract
Vitiligo is a disease of the skin characterized by the appearance of white spots. Significant progress has been made in understanding vitiligo pathogenesis over the past 30 years, but only through perseverance, collaboration, and open-minded discussion. Early hypotheses considered roles for innervation, microvascular anomalies, oxidative stress, defects in melanocyte adhesion, autoimmunity, somatic mosaicism, and genetics. Because theories about pathogenesis drive experimental design, focus, and even therapeutic approach, it is important to consider their impact on our current understanding about vitiligo. Animal models allow researchers to perform mechanistic studies, and the development of improved patient sample collection methods provides a platform for translational studies in vitiligo that can also be applied to understand other autoimmune diseases that are more difficult to study in human samples. Here we discuss the history of vitiligo translational research, recent advances, and their implications for new treatment approaches.
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Affiliation(s)
- Erica L Katz
- Department of Medicine, Division of Dermatology, University of Massachusetts Medical School, Worcester, MA, United States
| | - John E Harris
- Department of Medicine, Division of Dermatology, University of Massachusetts Medical School, Worcester, MA, United States
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8
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Lin X, Meng X, Song Z, Lin J. Nuclear factor erythroid 2-related factor 2 (Nrf2) as a potential therapeutic target for vitiligo. Arch Biochem Biophys 2020; 696:108670. [PMID: 33186606 DOI: 10.1016/j.abb.2020.108670] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/28/2020] [Accepted: 11/04/2020] [Indexed: 12/12/2022]
Abstract
Vitiligo is an autoimmune disease of the skin which causes loss of melanocytes from the epidermis. Recently, it is demonstrated that oxidative stress (OS) plays a significant role in the immuno-pathogenesis of vitiligo. A major mechanism in the cellular defense against OS is activation of the nuclear factor erythroid2-related factor (Nrf2)-Kelch-like ECH-associated protein 1(Keap1)-antioxidant responsive element (ARE) signaling pathway. Recently it has been shown that vitiligo melanocytes have impaired Nrf2-ARE signaling. A number of drugs including those known as Nrf2 activators and those known to possess effects to activate Nrf2, have been used in treating vitiligo with certain therapeutic effects. Also, studies have shown that a number of compounds can protect melanocytes against OS via activating Nrf2. These compounds may be considered as candidates for developing new drugs for vitiligo in the future. Nrf2 can be considered as a potential therapeutic target for vitiligo.
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Affiliation(s)
- Xiran Lin
- Department of Dermatology, First Affiliated Hospital of Dalian Medical University, 222 Zhongshan Lu, Dalian, 116011, China.
| | - Xianmin Meng
- Department of Pathology and Laboratory Medicine, Axia Women's Health, 450 Cresson BLVD, Oaks, PA, 19456, USA.
| | - Zhiqi Song
- Department of Dermatology, First Affiliated Hospital of Dalian Medical University, 222 Zhongshan Lu, Dalian, 116011, China.
| | - Jingrong Lin
- Department of Dermatology, First Affiliated Hospital of Dalian Medical University, 222 Zhongshan Lu, Dalian, 116011, China.
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9
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Abstract
Vitiligo is an autoimmune disease of the skin that targets pigment-producing melanocytes and results in patches of depigmentation that are visible as white spots. Recent research studies have yielded a strong mechanistic understanding of this disease. Autoreactive cytotoxic CD8+ T cells engage melanocytes and promote disease progression through the local production of IFN-γ, and IFN-γ-induced chemokines are then secreted from surrounding keratinocytes to further recruit T cells to the skin through a positive-feedback loop. Both topical and systemic treatments that block IFN-γ signaling can effectively reverse vitiligo in humans; however, disease relapse is common after stopping treatments. Autoreactive resident memory T cells are responsible for relapse, and new treatment strategies focus on eliminating these cells to promote long-lasting benefit. Here, we discuss basic, translational, and clinical research studies that provide insight into the pathogenesis of vitiligo, and how this insight has been utilized to create new targeted treatment strategies.
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Affiliation(s)
- Michael L. Frisoli
- University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA;, ,
| | - Kingsley Essien
- University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA;, ,
| | - John E. Harris
- University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA;, ,
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10
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Karagaiah P, Valle Y, Sigova J, Zerbinati N, Vojvodic P, Parsad D, Schwartz RA, Grabbe S, Goldust M, Lotti T. Emerging drugs for the treatment of vitiligo. Expert Opin Emerg Drugs 2020; 25:7-24. [PMID: 31958256 DOI: 10.1080/14728214.2020.1712358] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Introduction: Vitiligo is a relatively common autoimmune depigmenting disorder of the skin. There has been a great advance in understanding the pathological basis, which has led to the development and utilization of various new molecules in treating vitiligo. This review aims at a comprehensively describing the treatments available and the emerging treatment aspects and the scope for future developments.Areas covered: This study comprehensively summarizes the current concepts in the pathogenesis of vitiligo with special focus on the cytokine and signaling pathways, which are the targets for newer drugs. JAK kinase signaling pathways and the cytokines involved are the focus of vitiligo treatment in current research, followed by antioxidant mechanisms and repigmenting mechanisms. Topical immunosuppressants may be an alternative to steroids in localized vitiligo. Newer repigmenting agents like basic fibroblast growth factors, afamelanotide have been included and a special emphasis is laid on the upcoming targeted immunotherapy.Expert opinion: The treatment of vitiligo needs to be multimodal with emphasis on targeting different limbs of the pathogenesis. Topical and oral JAK inhibitors are the most promising new class of drugs currently available for treating vitiligo and acts best in conjunction with NB-UVB.
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Affiliation(s)
- Priyanka Karagaiah
- Department of Dermatology, Bangalore Medical College and Research Institute, Bangalore, India
| | - Yan Valle
- Vitiligo Research Foundation, New York, NY, USA
| | - Julia Sigova
- Pirogov Russian National Research Medical University, Moscow, Russia
| | - Nicola Zerbinati
- Universita degli Studi dell'Insubria Dipartimento di Scienze Chirurgiche e Morfologiche, Varese, Italy
| | - Petar Vojvodic
- Clinic for Mental Disorders "Dr Laza Lazarevic", Belgrade, Serbia
| | | | | | - Stephan Grabbe
- Department of Dermatology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Mohamad Goldust
- University of Rome Guglielmo Marconi, Rome, Italy, Department of Dermatology, University Medical Center Mainz, Mainz, Germany
| | - Torello Lotti
- Department of Dermatology, University of Studies Guglielmo Marconi, Rome, Italy
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11
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Vitiligo susceptibility at workplace and in daily life: the contribution of oxidative stress gene polymorphisms. BIOMEDICAL DERMATOLOGY 2019. [DOI: 10.1186/s41702-019-0043-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Abstract
Objective
Vitiligo is a frequently underestimated and little known dermal disease whose symptoms appear as white patches on several skin areas of the body. In this review, the impact of idiopathic and chemical-induced vitiligo at workplace and in daily life is discussed. Also, the influence of selected oxidative stress gene polymorphisms on melanocyte damage is described to understand their involvement in the disease.
Methods
A PubMed search was carried out to select the journal articles reporting an association between specific oxidative stress polymorphic genes and vitiligo.
Results
The double-null glutathione S-transferase T1 and M1 genotypes are associated with vitiligo while the relationship between nuclear factor erythroid 2-related factor 2, heme oxygenase, catalase and superoxide dismutase gene polymorphisms and the disease should be confirmed by further studies.
Conclusions
The polymorphic genes analysed here may have a role in the susceptibility of patients affected by vitiligo, while little is known about the affected workers, due to the lack of epidemiologic data on these subjects. However, the similarity of the skin lesions observed in both groups might have in common some genetic factors making all these individuals susceptible to the development of vitiligo, regardless of the disease-triggering factor.
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Chen X, Guo W, Chang Y, Chen J, Kang P, Yi X, Cui T, Guo S, Xiao Q, Jian Z, Li K, Gao T, Li S, Liu L, Li C. Oxidative stress-induced IL-15 trans-presentation in keratinocytes contributes to CD8 + T cells activation via JAK-STAT pathway in vitiligo. Free Radic Biol Med 2019; 139:80-91. [PMID: 31078730 DOI: 10.1016/j.freeradbiomed.2019.05.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/02/2019] [Accepted: 05/08/2019] [Indexed: 01/06/2023]
Abstract
Oxidative stress and effector memory CD8+ T cells have been greatly implicated in vitiligo pathogenesis. However, the crosstalk between these two crucial pathogenic factors has been merely investigated. IL-15 has been regarded as an important cytokine exerting its facilitative effect on memory CD8+ T cells function in various autoimmune diseases. In the present study, we initially discovered that the IL-15 expression was significantly increased in vitiligo epidermis and highly associated with epidermal H2O2 content. In addition, epidermal IL-15 expression was mainly derived from keratinocytes. Then, we showed that oxidative stress promoted IL-15 and IL-15Rα expression as well as IL-15 trans-presentation by activating NF-κB signaling in keratinocytes. What's more, the trans-presented IL-15, rather than the secreted one, was accounted for the potentiation of CD8+ TEMs activation. We further investigated the mechanism underlying trans-presented IL-15 in potentiating CD8+ TEMs activation and found that the blockage of IL-15-JAK-STAT signaling could be a potent therapeutic approach. Taken together, our results demonstrate that oxidative stress-induced IL-15 trans-presentation in keratinocytes contributes to the activation of CD8+ TEMs, providing a novel mechanism by which oxidative stress initiates autoimmunity in vitiligo.
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Affiliation(s)
- Xuguang Chen
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Weinan Guo
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Yuqian Chang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jiaxi Chen
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Pan Kang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xiuli Yi
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Tingting Cui
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Sen Guo
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Qian Xiao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Zhe Jian
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Kai Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Tianwen Gao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Shuli Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
| | - Ling Liu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
| | - Chunying Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
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13
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Rosado C, Tokunaga VK, Sauce R, de Oliveira CA, Sarruf FD, Parise-Filho R, Maurício E, de Almeida TS, Velasco MVR, Baby AR. Another Reason for Using Caffeine in Dermocosmetics: Sunscreen Adjuvant. Front Physiol 2019; 10:519. [PMID: 31130869 PMCID: PMC6509748 DOI: 10.3389/fphys.2019.00519] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 04/11/2019] [Indexed: 12/23/2022] Open
Abstract
The excessive exposure to ultraviolet (UV) radiation is the main cause of skin cancer, the most commonly diagnosed cancer in the world. In this context, the development of innovative and more effective sunscreens, with bioactive compounds like caffeine, displaying antioxidant and anticancer potential, is required. This research work assessed in vitro and in vivo the efficacy and safety of topical sunscreen formulations containing caffeine as an adjuvant of the UV filters. Sunscreens were prepared with 2.5% w/w caffeine or in the absence of this compound. In order to evaluate the safety of these formulations, stratum corneum hydration, skin barrier and colorimetry were assessed in vivo in healthy subjects before and after skin treatment with the samples. The efficacy of the sunscreens was assessed in vitro, using PMMA plates and a spectrophotometer equipped with an integrating sphere; and in vivo by the determination of the sun protection factor (SPF). None of the formulations caused erythema or impaired the skin barrier function. The in vitro functional characterization showed higher SPF values for the caffeine formulation. The in vivo studies also confirmed the higher SPF value of the formulation combining caffeine with the filters, compared to the caffeine-free sample. This improvement contributed to an increase of, approximately, 25% in the in vivo anti-UVB protection. In conclusion, caffeine was well tolerated by the skin and increased the photoprotective activity, being a new alternative adjuvant in sunscreens formulation.
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Affiliation(s)
- Catarina Rosado
- CBIOS – Research Center for Biosciences and Health Technologies, Universidade Lusófona, Lisbon, Portugal
| | - Viviane Kaori Tokunaga
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rafael Sauce
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Camila Areias de Oliveira
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Roberto Parise-Filho
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Elisabete Maurício
- CBIOS – Research Center for Biosciences and Health Technologies, Universidade Lusófona, Lisbon, Portugal
| | - Tânia Santos de Almeida
- CBIOS – Research Center for Biosciences and Health Technologies, Universidade Lusófona, Lisbon, Portugal
| | | | - André Rolim Baby
- Department of Pharmacy, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
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14
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Ma J, Li S, Zhu L, Guo S, Yi X, Cui T, He Y, Chang Y, Liu B, Li C, Jian Z. Baicalein protects human vitiligo melanocytes from oxidative stress through activation of NF-E2-related factor2 (Nrf2) signaling pathway. Free Radic Biol Med 2018; 129:492-503. [PMID: 30342186 DOI: 10.1016/j.freeradbiomed.2018.10.421] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/26/2018] [Accepted: 10/09/2018] [Indexed: 12/30/2022]
Abstract
Vitiligo is a complex disorder characterized by patchy loss of skin pigmentation due to abnormal melanocyte function. Overwhelming evidences have suggested that oxidative stress plays a major role in the loss of melanocytes thereby mediating the onset and progression of vitiligo. The nuclear factor erythroid 2-like factor 2 (Nrf2) is a master regulator of cellular redox homeostasis and the activation of Nrf2 signaling pathway is impaired in the vitiligo melanocytes. Baicalein, as flavonoid extracted from the Scutellaria baicalensis, has been proved to possess the ability to activate Nrf2 signaling pathway in other cell types and mouse model. Our previous data found that baicalein exerts a cytoprotective role in H2O2-induced apoptosis in human melanocytes cell line (PIG1). Based on these founding, we hypothesized that baicalein activates Nrf2 signaling pathway, alleviates H2O2-induced mitochondrial dysfunction and cellular damage, thereby protecting human vitiligo melanocytes from oxidative stress. In the present study, we found that baicalein effectively inhibited H2O2-induced cytotoxicity and apoptosis in human vitiligo melanocytes (PIG3V). Further results demonstrated that baicalein promoted Nrf2 nucleus translocation as well as up-regulated the expression of Nrf2 and its target gene, heme oxygenase-1 (HO-1). Moreover, the protective effects of baicalein against H2O2-induced cellular damage and apoptosis as well as mitochondrial dysfunction were abolished by Nrf2 knockdown. Additionally, we observed that Nrf2 knockdown suppressed proliferation and increased the sensitivity of PIG3V cells to H2O2 treatment. Finally, we explored the mechanism of baicalein associated with Nrf2 activation and found that the phosphorylation of Nrf2 as well as ERK1/2and PI3K/AKT signaling were not involved in the baicalein-induced activation of Nrf2. Taken together, these data clearly suggest that baicalein enhances cellular antioxidant defense capacity of human vitiligo melanocytes through the activation of the Nrf2 signaling pathway, providing beneficial evidence for the application of baicalein in the vitiligo treatment.
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Affiliation(s)
- Jingjing Ma
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Shuli Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Longfei Zhu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Sen Guo
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Xiuli Yi
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Tingting Cui
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Yuanmin He
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Yuqian Chang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China
| | - Bangmin Liu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China.
| | - Chunying Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China.
| | - Zhe Jian
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, No. 127 Changlexi Road, Xi'an 710032, Shaanxi, China.
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Guan CP, Li QT, Jiang H, Geng QW, Xu W, Li LY, Xu AE. IGF-1 resist oxidative damage to HaCaT and depigmentation in mice treated with H2O2. Biochem Biophys Res Commun 2018; 503:2485-2492. [DOI: 10.1016/j.bbrc.2018.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 07/02/2018] [Indexed: 12/31/2022]
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Antroquinonol Exerts Immunosuppressive Effect on CD8 + T Cell Proliferation and Activation to Resist Depigmentation Induced by H 2O 2. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:9303054. [PMID: 29456788 PMCID: PMC5804328 DOI: 10.1155/2017/9303054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/17/2017] [Accepted: 10/10/2017] [Indexed: 01/01/2023]
Abstract
Antroquinonol was investigated as antioxidant and inhibition of inflammatory responses. Our study was to evaluate its immunosuppressive effect on CD8+ T cells and protective effect on depigmentation. CD8+ T cells were treated with antroquinonol in vitro, and C57BL/6 mice were treated with antroquinonol with or without H2O2in vivo for 50 consecutive days. We found antroquinonol could inhibit proliferation of CD8+ T cells and suppress the production of cytokines IL-2 and IFN-γ and T cell activation markers CD69 and CD137 in vitro. H2O2 treatment induced depigmentation and reduced hair follicle length, skin thickness, and tyrosinase expression in vivo. Whereas, antroquinonol obviously ameliorated depigmentation of mice skin and resisted the reduction of hair follicle length, skin thickness, and tyrosinase expression induced by H2O2. Antroquinonol decreased CD8+ T cell infiltration in mice skin, inhibited the production of IL-2 and IFN-γ, and decreased the expression of CXCL10 and CXCR3. Summarily, our data shows antroquinonol inhibits CD8+ T cell proliferation in vitro. It also reduces CD8+ T cell infiltration and proinflammatory cytokine secretion and suppresses the thinning of epidermal layer in vivo. Our findings suggest that antroquinonol exerts immunosuppressive effects on CD8+ T cell proliferation and activation to resist depigmentation induced by H2O2.
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Association of CAT 389 T/C and − 89 T/A gene polymorphisms with vitiligo. JOURNAL OF THE EGYPTIAN WOMEN’S DERMATOLOGIC SOCIETY 2017. [DOI: 10.1097/01.ewx.0000512171.26140.d3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
The pathogenesis of vitiligo involves interplay between intrinsic and extrinsic melanocyte defects, innate immune inflammation, and T-cell-mediated melanocyte destruction. The goal of treatment is to not only halt disease progression but also promote repigmentation through melanocyte regeneration, proliferation, and migration. Treatment strategies that address all aspects of disease pathogenesis and repigmentation are likely to have greatest efficacy, a strategy that may require combination therapies. Current treatments generally involve nontargeted suppression of autoimmunity, whereas emerging treatments are likely to use a more targeted approach based on in-depth understanding of disease pathogenesis, which may provide higher efficacy with a good safety profile.
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Affiliation(s)
- Mehdi Rashighi
- Department of Dermatology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Dermatology, Tehran University of Medical Sciences, 415 Taleqani Avenue, Tehran 1416613675, Iran
| | - John E Harris
- Department of Dermatology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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Li S, Zhu G, Yang Y, Jian Z, Guo S, Dai W, Shi Q, Ge R, Ma J, Liu L, Li K, Luan Q, Wang G, Gao T, Li C. Oxidative stress drives CD8 + T-cell skin trafficking in patients with vitiligo through CXCL16 upregulation by activating the unfolded protein response in keratinocytes. J Allergy Clin Immunol 2016; 140:177-189.e9. [PMID: 27826097 DOI: 10.1016/j.jaci.2016.10.013] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 08/17/2016] [Accepted: 10/03/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND In patients with vitiligo, an increased reactive oxygen species (ROS) level has been proved to be a key player during disease initiation and progression in melanocytes. Nevertheless, little is known about the effects of ROS on other cells involved in the aberrant microenvironment, such as keratinocytes and the following immune events. CXCL16 is constitutively expressed in keratinocytes and was recently found to mediate homing of CD8+ T cells in human skin. OBJECTIVE We sought to explicate the effect of oxidative stress on human keratinocytes and its capacity to drive CD8+ T-cell trafficking through CXCL16 regulation. METHODS We first detected putative T-cell skin-homing chemokines and ROS in serum and lesions of patients with vitiligo. The production of candidate chemokines was detected by using quantitative real-time PCR and ELISA in keratinocytes exposed to H2O2. Furthermore, the involved mediators were analyzed by using quantitative real-time PCR, Western blotting, ELISA, and immunofluorescence. Next, we tested the chemotactic migration of CD8+ T cells from patients with vitiligo mediated by the CXCL16-CXCR6 pair using the transwell assay. RESULTS CXCL16 expression increased and showed a positive correlation with oxidative stress levels in serum and lesions of patients with vitiligo. The H2O2-induced CXCL16 expression was due to the activation of 2 unfolded protein response pathways: kinase RNA (PKR)-like ER kinase-eukaryotic initiation factor 2α and inositol-requiring enzyme 1α-X-box binding protein 1. CXCL16 produced by stressed keratinocytes induced migration of CXCR6+CD8+ T cells derived from patients with vitiligo. CXCR6+CD8+ T-cell skin infiltration is accompanied by melanocyte loss in lesions of patients with vitiligo. CONCLUSION Our study demonstrated that CXCL16-CXCR6 mediates CD8+ T-cell skin trafficking under oxidative stress in patients with vitiligo. The CXCL16 expression in human keratinocytes induced by ROS is, at least in part, caused by unfolded protein response activation.
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Affiliation(s)
- Shuli Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Guannan Zhu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Yuqi Yang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Zhe Jian
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Sen Guo
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Wei Dai
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Qiong Shi
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Rui Ge
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Jingjing Ma
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Ling Liu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Kai Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Qi Luan
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Gang Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Tianwen Gao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China
| | - Chunying Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi, China.
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Harris JE. Cellular stress and innate inflammation in organ-specific autoimmunity: lessons learned from vitiligo. Immunol Rev 2016; 269:11-25. [PMID: 26683142 DOI: 10.1111/imr.12369] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
For decades, research in autoimmunity has focused primarily on immune contributions to disease. Yet recent studies report elevated levels of reactive oxygen species and abnormal activation of the unfolded protein response in cells targeted by autoimmunity, implicating cellular stress originating from the target tissue as a contributing factor. A better understanding of this contribution may help to answer important lingering questions in organ-specific autoimmunity, as to what factors initiate disease and what directs its tissue specificity. Vitiligo, an autoimmune disease of the skin, has been the focus of translational research for over 30 years, and both melanocyte stress and immune mechanisms have been thought to be mutually exclusive explanations for pathogenesis. Chemical-induced vitiligo is a unique clinical presentation that reflects the importance of environmental influences on autoimmunity, provides insight into a new paradigm linking cell stress to the immune response, and serves as a template for other autoimmune diseases. In this review, I will discuss the evidence for cell stress contributions to a number of autoimmune diseases, the questions that remain, and how vitiligo, an underappreciated example of organ-specific autoimmunity, helps to answer them.
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Affiliation(s)
- John E Harris
- Department of Medicine, Division of Dermatology, University of Massachusetts Medical School, Worcester, MA, USA
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Song P, Li K, Liu L, Wang X, Jian Z, Zhang W, Wang G, Li C, Gao T. Genetic polymorphism of the Nrf2 promoter region is associated with vitiligo risk in Han Chinese populations. J Cell Mol Med 2016; 20:1840-50. [PMID: 27222475 PMCID: PMC5020638 DOI: 10.1111/jcmm.12874] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 03/10/2016] [Indexed: 12/11/2022] Open
Abstract
The nuclear factor erythroid‐derived two‐like 2‐antioxidant response element (Nrf2‐ARE) pathway and its downstream antioxidant enzyme heme oxygenase‐1 (HMOX1 or HO‐1) play essential roles in H2O2‐induced oxidative damage in human melanocytes. However, the link between Nrf2 promoter polymorphisms and susceptibility to oxidative stress‐related diseases such as vitiligo is unknown. This study evaluated the association of the Nrf2 and HO‐1 genes polymorphisms with vitiligo susceptibility. In this case–control study of 1136 Han Chinese vitiligo patients and 1200 controls, Nrf2 (rs35652124 and rs6721961) and HO‐1 (rs2071746) genes were genotyped by PCR‐restriction fragment length polymorphism analysis. Overall, a significantly decreased risk of vitiligo was found to be associated with Nrf2 rs35652124 CC and combined (CT+CC) genotypes [odds ratio (OR) 0.64, 95% confidence interval (CI) 0.50–0.83 and OR, 0.84, 95% CI 0.71–0.99, respectively], as well as among subgroups: female, onset age ≤20 and never smoker. We subsequently found that Nrf2 rs35652124 C allele had higher transcriptional activity in the luciferase reporter assay compared with Nrf2 rs35652124 T allele. Furthermore, we investigated serum HO‐1 activity was associated with the rs35652124 CT+CC genotype and lower in patients than in controls (P = 0.024). Logistic regression analysis showed a dose–response relationship between lower vitiligo risk and increased HO‐1 activity in rs35652124 CT+CC genotype carriers (Ptrend < 0.05). These findings indicate that the C allele of rs35652124 located in the promoter region of Nrf2 gene is associated with protective effect on vitiligo in a Han Chinese population.
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Affiliation(s)
- Pu Song
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Kai Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Ling Liu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Xiaowen Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Zhe Jian
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Weigang Zhang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Gang Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Chunying Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
| | - Tianwen Gao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
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Impaired activation of the Nrf2-ARE signaling pathway undermines H2O2-induced oxidative stress response: a possible mechanism for melanocyte degeneration in vitiligo. J Invest Dermatol 2014; 134:2221-2230. [PMID: 24662764 DOI: 10.1038/jid.2014.152] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 02/07/2014] [Accepted: 02/25/2014] [Indexed: 12/22/2022]
Abstract
Vitiligo melanocytes possess higher susceptibility to oxidative insults. Consistent with this, impairment of the antioxidant defense system has been reported to be involved in the onset and progression of vitiligo. Our previous study showed that the nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway and its downstream antioxidant enzyme heme oxygenase-1 (HO-1) are crucial for melanocytes to cope with H2O2-induced oxidative damage. Here, we sought to determine whether the diminished Nrf2-ARE activity that contributes to reduced downstream antioxidant enzymes and increased oxidative stress could be the reason why melanocytes are more vulnerable to vitiligo. We found that vitiligo melanocytes exhibited hypersensitivity to H2O2-induced oxidative injury because of reduced Nrf2 nuclear translocation and transcriptional activity, which led to decreased HO-1 expression and aberrant redox balance. Moreover, we also found that the level of serum HO-1 was significantly decreased and that of IL-2 was markedly increased in 113 vitiligo patients when compared with healthy controls. These data demonstrate that impaired activation of Nrf2 under oxidative stress could result in decreased expression of antioxidant enzymes and increased death of vitiligo melanocytes.
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Richmond JM, Frisoli ML, Harris JE. Innate immune mechanisms in vitiligo: danger from within. Curr Opin Immunol 2013; 25:676-82. [PMID: 24238922 DOI: 10.1016/j.coi.2013.10.010] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 10/09/2013] [Accepted: 10/09/2013] [Indexed: 12/22/2022]
Abstract
Vitiligo is an autoimmune disease of the skin in which melanocytes are destroyed by antigen-specific T cells, resulting in patchy depigmentation. Although adaptive immunity plays a clear role in disease progression, initiating factors are largely unknown. Many studies report that cellular stress pathways are dysregulated in melanocytes from vitiligo patients, suggesting that melanocyte-intrinsic defects participate in disease pathogenesis. Recent studies reveal that melanocyte stress generates damage-associated molecular patterns that activate innate immunity, thus connecting stress to organ-specific inflammation. Genetic studies in vitiligo support a role for stress, innate immunity, and adaptive mechanisms. Here, we discuss advances in the field that highlight how cellular stress, endogenous danger signals, and innate immune activation promote the onset of vitiligo.
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Affiliation(s)
- Jillian M Richmond
- Department of Medicine, Division of Dermatology, University of Massachusetts Medical School, 364 Plantation St., LRB 325, Worcester, MA 01605, USA
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Abstract
BACKGROUND Vitiligo is a commonly encountered pigmentary disorder. Numerous studies and investigations from all over the world have attempted to determine the mechanisms behind this disease; however, the pathogenesis of vitiligo remains elusive. OBJECTIVE n this comprehensive review article, we present the findings behind the five overarching theories of what causes this disfiguring and psychologically debilitating disease. METHOD We begin our discussion with the role of genetic predisposition and move onward to the neural theory first proposed in the 1950s. Next we discuss the autoimmune hypothesis, followed by the reactive oxygen species model, and conclude by describing the findings of the more recent melanocytorrhagy hypothesis. CONCLUSION Although the exact pathogenesis of vitiligo is uncertain, each of these theories likely plays a role. Understanding each theory would pave the way for therapeutic advances for this disease.
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Affiliation(s)
- Neel Malhotra
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
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Abstract
Background: Vitiligo is a common depigmented skin disorder that is caused by selective destruction of melanocytes. It is generally accepted that the main function of melanin resides in the protection of skin cells against the deleterious effect of ultraviolet rays (UVRs). Association of vitiligo and skin cancer has been a subject of controversy. Occurrence of skin cancer in long-lasting vitiligo is rare despite multiple evidences of DNA damage in vitiliginous skin. Aim: To detect the expression of P53 and Mdm2 proteins in both depigmented and normally pigmented skin of vitiligo patients and to compare it to control subjects suffering from nonmelanoma skin cancer (NMSC). Materials and Methods: Thirty-four patients with vitiligo and 30 age and sex-matched patients with nodulo-ulcerative basal cell carcinoma (BCC) as a control group were selected. Both patients and control subjects had outdoor occupations. Skin biopsies were taken from each case and control subjects. Histopathological examination of Hematoxylin and eosin-stained sections was done. Expression of P53 and Mdm2 proteins were examined immunohistochemically. Results: Both P53 and Mdm2 were strongly expressed in depigmented as well as normally pigmented skin of vitiligo patients. This expression involved the epidermis, skin adnexa and blood vessels with significant differences between cases and controls. Conclusions: The overexpression of P53 and Mdm2 proteins in both normally pigmented and depigmented skin of patients with vitiligo could contribute to the decreased occurrence of actinic damage and NMSC in these patients.
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Affiliation(s)
- Ola A Bakry
- Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine, Menoufiya University, Menoufiya, Egypt
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Schallreuter KU, Salem MAEL, Gibbons NCJ, Maitland DJ, Marsch E, Elwary SMA, Healey AR. Blunted epidermal L-tryptophan metabolism in vitiligo affects immune response and ROS scavenging by Fenton chemistry, part 2: Epidermal H2O2/ONOO(-)-mediated stress in vitiligo hampers indoleamine 2,3-dioxygenase and aryl hydrocarbon receptor-mediated immune response signaling. FASEB J 2012; 26:2471-85. [PMID: 22415306 DOI: 10.1096/fj.11-201897] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Vitiligo is characterized by a mostly progressive loss of the inherited skin color. The cause of the disease is still unknown, despite accumulating in vivo and in vitro evidence of massive oxidative stress via hydrogen peroxide (H(2)O(2)) and peroxynitrite (ONOO(-)) in the skin of affected individuals. The most favored hypothesis is based on autoimmune mechanisms. Since depletion of the essential amino acid L-tryptophan (Trp) severely affects various immune responses, we here looked at Trp metabolism and signaling in these patients. Our in vivo and in vitro data revealed total absence of epidermal Trp hydroxylase activities and the presence of H(2)O(2)/ONOO(-) deactivated indoleamine 2,3-dioxygenase. Aryl hydrocarbon receptor signaling is severely impaired despite the ligand (Trp dimer) being formed, as shown by mass spectrometry. Loss of this signal is supported by the absence of downstream signals (COX-2 and CYP1A1) as well as regulatory T-lymphocytes and by computer modeling. In vivo Fourier transform Raman spectroscopy confirmed the presence of Trp metabolites together with H(2)O(2) supporting deprivation of the epidermal Trp pool by Fenton chemistry. Taken together, our data support a long-expressed role for in loco redox balance and a distinct immune response. These insights could open novel treatment strategies for this disease.
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Affiliation(s)
- Karin U Schallreuter
- Institute for Pigmentary Disorders, E. M. Arndt University, Greifswald, Germany.
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Schallreuter KU, Salem MAEL, Gibbons NCJ, Martinez A, Slominski R, Lüdemann J, Rokos H. Blunted epidermal L-tryptophan metabolism in vitiligo affects immune response and ROS scavenging by Fenton chemistry, part 1: Epidermal H2O2/ONOO(-)-mediated stress abrogates tryptophan hydroxylase and dopa decarboxylase activities, leading to low serotonin and melatonin levels. FASEB J 2012; 26:2457-70. [PMID: 22415302 DOI: 10.1096/fj.11-197137] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Vitiligo is characterized by a progressive loss of inherited skin color. The cause of the disease is still unknown. To date, there is accumulating in vivo and in vitro evidence for massive oxidative stress via hydrogen peroxide (H(2)O(2)) and peroxynitrite (ONOO(-)) in the skin of affected individuals. Autoimmune etiology is the favored theory. Since depletion of the essential amino acid L-tryptophan (Trp) affects immune response mechanisms, we here looked at epidermal Trp metabolism via tryptophan hydroxylase (TPH) with its downstream cascade, including serotonin and melatonin. Our in situ immunofluorescence and Western blot data reveal significantly lower TPH1 expression in patients with vitiligo. Expression is also low in melanocytes and keratinocytes under in vitro conditions. Although in vivo Fourier transform-Raman spectroscopy proves the presence of 5-hydroxytryptophan, epidermal TPH activity is completely absent. Regulation of TPH via microphthalmia-associated transcription factor and L-type calcium channels is severely affected. Moreover, dopa decarboxylase (DDC) expression is significantly lower, in association with decreased serotonin and melatonin levels. Computer simulation supports H(2)O(2)/ONOO(-)-mediated oxidation/nitration of TPH1 and DDC, affecting, in turn, enzyme functionality. Taken together, our data point to depletion of epidermal Trp by Fenton chemistry and exclude melatonin as a relevant contributor to epidermal redox balance and immune response in vitiligo.
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Affiliation(s)
- Karin U Schallreuter
- Institute for Pigmentary Disorders, E. M. Arndt University, Greifswald, Germany.
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Estimation of paraoxonase-1 and superoxide dismutase in vitiligo patients before and after photochemotherapy. JOURNAL OF THE EGYPTIAN WOMEN’S DERMATOLOGIC SOCIETY 2012. [DOI: 10.1097/01.ewx.0000407198.54491.64] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Kemp EH, Emhemad S, Akhtar S, Watson PF, Gawkrodger DJ, Weetman AP. Autoantibodies against tyrosine hydroxylase in patients with non-segmental (generalised) vitiligo. Exp Dermatol 2011; 20:35-40. [PMID: 21158937 DOI: 10.1111/j.1600-0625.2010.01181.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Vitiligo is an acquired idiopathic hypomelanotic skin disorder characterised by depigmented macules because of loss of cutaneous melanocytes. Although the exact cause of vitiligo remains obscure, evidence suggests that autoimmunity plays a role in the pathogenesis of the disease. Previously, tyrosine hydroxylase (TH) was identified as a putative autoantigen in vitiligo using phage-display technology. In this study, the prevalence of TH antibodies in patients with vitiligo was investigated. A radioimmunoassay (RIA) was used to detect TH antibodies in sera from patients with either non-segmental vitiligo (n=79), segmental vitiligo (n=8) or other autoimmune diseases without concomitant vitiligo (n=91). Sera from healthy individuals (n=28) were also tested. Patients with segmental vitiligo, healthy controls and patients with other autoimmune diseases without concomitant vitiligo were all negative for TH antibody reactivity. Of 79 patients with non-segmental vitiligo, 18 (23%) were positive for TH antibodies in the RIA, and a significant increase in the prevalence of TH antibodies in patients with non-segmental vitiligo was evident when compared with controls (P=0.003). TH antibody prevalence was also significantly elevated in patients with active vitiligo compared to those with stable disease (P=0.009). Overall, the results indicate that TH is an antibody target in non-segmental but not in segmental vitiligo and that TH antibodies appear to be more frequent in patients with active vitiligo.
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Affiliation(s)
- E Helen Kemp
- Department of Human Metabolism, School of Medicine, University of Sheffield, Sheffield, UK.
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Elassiuty YE, Klarquist J, Speiser J, Yousef RM, El Refaee AA, Hunter NS, Shaker OG, Gundeti M, Nieuweboer-Krobotova L, Le Poole IC. Heme oxygenase-1 expression protects melanocytes from stress-induced cell death: implications for vitiligo. Exp Dermatol 2011; 20:496-501. [PMID: 21426408 DOI: 10.1111/j.1600-0625.2010.01232.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
To study protection of melanocytes from stress-induced cell death by heme oxygenases during depigmentation and repigmentation in vitiligo, expression of isoforms 1 and 2 was studied in cultured control and patient melanocytes and normal skin explants exposed to UV or bleaching agent 4-TBP. Similarly, expression of heme oxygenases was followed in skin from vitiligo patients before and after PUVA treatment. Single and double immunostainings were used in combination with light and confocal microscopic analysis and Western blotting. Melanocyte expression of heme oxygenase 1 is upregulated, whereas heme oxygenase 2 is reduced in response to UV and 4-TBP. Upregulation of inducible heme oxygenase 1 was also observed in UV-treated explant cultures, in skin of successfully PUVA-treated patients and in melanocytes cultured from vitiligo non-lesional skin. Heme oxygenase encoding genes were subsequently cloned to study consequences of either gene product on cell viability, demonstrating that HO-1 but not HO-2 overexpression offers protection from stress-induced cell death in MTT assays. HO-1 expression by melanocytes may contribute to beneficial effects of UV treatment for vitiligo patients.
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Affiliation(s)
- Yasser E Elassiuty
- Department of Pathology, Microbiology and Immunology/Oncology Institute, Loyola University Chicago, IL, USA
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Westerhof W, Manini P, Napolitano A, d’Ischia M. The haptenation theory of vitiligo and melanoma rejection: a close-up. Exp Dermatol 2011; 20:92-6. [DOI: 10.1111/j.1600-0625.2010.01200.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Vafaee T, Rokos H, Salem MMAEL, Schallreuter KU. In vivo and in vitro evidence for epidermal H2O2-mediated oxidative stress in piebaldism. Exp Dermatol 2011; 19:883-7. [PMID: 19758321 DOI: 10.1111/j.1600-0625.2009.00966.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Piebaldism is characterised by the absence of pigment in patches on the skin, usually present at birth. Mutations in the kit gene are documented. Clinically this disorder can mimic vitiligo. Here, we show for the first time the presence of oxidised pteridine-induced fluorescence in association with H2O2-mediated stress in piebald patches employing Wood's light and in vivo FT-Raman spectroscopy. In situ immunofluorescence data revealed low catalase and methionine sulphoxide reductase A (MSRA) levels whereas thioredoxin reductase and methionine sulphoxide reductase B (MSRB) are not affected. We also show low superoxide dismutase levels in these patients. The presence of thioredoxin reductase provides capacity to reduce H2O2, a mechanism which is absent in vitiligo. Importantly, this enzyme reduces biopterin back to the functioning cofactor 6-tetrahydrobiopterin. The absence of MSRA indicates deficient methionine sulphoxide repair in the cytosol, meanwhile the presence of MSRB is helpful to protect the nucleus. Taken together, we have identified H2O2-mediated stress in piebald skin with distinct differences to vitiligo.
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Affiliation(s)
- Tayyebeh Vafaee
- Institute for Pigmentary Disorders in association with EM Arndt University of Greifswald, Germany
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Abstract
The acquired depigmenting disorder of vitiligo affects an estimated 1% of the world population and constitutes one of the commonest dermatoses. Although essentially asymptomatic, the psychosocial impact of vitiligo can be severe. The cause of vitiligo remains enigmatic, hampering efforts at successful therapy. The underlying pathogenesis of the pigment loss has, however, been clarified to some extent in recent years, offering the prospect of effective treatment, accurate prognosis and rational preventative strategies. Vitiligo occurs when functioning melanocytes disappear from the epidermis. A single dominant pathway is unlikely to account for all cases of melanocyte loss in vitiligo; rather, it is the result of complex interactions of biochemical, environmental and immunological events, in a permissive genetic milieu. ROS (reactive oxygen species) and H2O2 in excess can damage biological processes, and this situation has been documented in active vitiligo skin. Tyrosinase activity is impaired by excess H2O2 through oxidation of methionine residues in this key melanogenic enzyme. Mechanisms for repairing this oxidant damage are also damaged by H2O2, compounding the effect. Numerous proteins and peptides, in addition to tyrosinase, are similarly affected. It is possible that oxidant stress is the principal cause of vitiligo. However, there is also ample evidence of immunological phenomena in vitiligo, particularly in established chronic and progressive disease. Both innate and adaptive arms of the immune system are involved, with a dominant role for T-cells. Sensitized CD8+ T-cells are targeted to melanocyte differentiation antigens and destroy melanocytes either as the primary event in vitiligo or as a secondary promotive consequence. There is speculation on the interplay, if any, between ROS and the immune system in the pathogenesis of vitiligo. The present review focuses on the scientific evidence linking alterations in ROS and/or T-cells to vitiligo.
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Natarajan VT, Singh A, Kumar AA, Sharma P, Kar HK, Marrot L, Meunier JR, Natarajan K, Rani R, Gokhale RS. Transcriptional Upregulation of Nrf2-Dependent Phase II Detoxification Genes in the Involved Epidermis of Vitiligo Vulgaris. J Invest Dermatol 2010; 130:2781-9. [DOI: 10.1038/jid.2010.201] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Lv YJ, Liao WJ, Luan Q, Wang H, Wang L, Li Q. The polymorphism of catalase T/C codon 389 in exon 9 and vitiligo susceptibility: a meta-analysis. J Eur Acad Dermatol Venereol 2010; 25:955-8. [PMID: 21054578 DOI: 10.1111/j.1468-3083.2010.03897.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The exact aetiology of vitiligo has not yet been established. Oxidative stress is involved in the pathophysiology of vitiligo. It has been described that some polymorphisms in the catalase (CAT) gene may affect the risk of vitiligo. However, the results were inconsistent. OBJECTIVE We performed a meta-analysis of the published studies to derive a more precise estimate of the association between CAT T/C at codon 389 in exon 9 polymorphisms and vitiligo risk. METHODS The PubMed, Medline, Cochrane Library, China National Knowledge Infrastructure (CNKI) databases were searched to identify relevant published studies. RESULTS Four case-control studies (cases, 645; controls, 689) that investigated the association between C/T polymorphisms of CAT exon 9 and the risk of vitiligo were retrieved and analysed. Our findings suggested a significant association between the CAT T/C exon 9 polymorphism and vitiligo risk (CT + TT vs. CC pooled odds ratio, 1.43; 95% confidence interval, 1.14-1.80; P = 0 .002). CONCLUSION We found a significant correlation between the CAT T/C exon 9 polymorphism and the risk of vitiligo.
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Affiliation(s)
- Y J Lv
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Shaanxi Province, China
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Salem MMAEL, Shalbaf M, Gibbons NCJ, Chavan B, Thornton JM, Schallreuter KU. Enhanced DNA binding capacity on up‐regulated epidermal wild‐type p53 in vitiligo by H
2
O
2
‐mediated oxidation: a possible repair mechanism for DNA damage. FASEB J 2009; 23:3790-807. [PMID: 19641144 DOI: 10.1096/fj.09-132621] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mohamed M. A. E. L. Salem
- Clinical and Experimental Dermatology Department of Biomedical Sciences/Centre for Skin Sciences School of Life Sciences University of Bradford Bradford UK
| | - Mohammad Shalbaf
- Clinical and Experimental Dermatology Department of Biomedical Sciences/Centre for Skin Sciences School of Life Sciences University of Bradford Bradford UK
| | - Nicholas C. J. Gibbons
- Clinical and Experimental Dermatology Department of Biomedical Sciences/Centre for Skin Sciences School of Life Sciences University of Bradford Bradford UK
- University of Bradford Bradford UK
| | - Bhaven Chavan
- Clinical and Experimental Dermatology Department of Biomedical Sciences/Centre for Skin Sciences School of Life Sciences University of Bradford Bradford UK
| | - J. M. Thornton
- Clinical and Experimental Dermatology Department of Biomedical Sciences/Centre for Skin Sciences School of Life Sciences University of Bradford Bradford UK
| | - Karin U. Schallreuter
- Clinical and Experimental Dermatology Department of Biomedical Sciences/Centre for Skin Sciences School of Life Sciences University of Bradford Bradford UK
- Institute for Pigmentary Disorders in association with E. M. Arndt University Greifswald Germany
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Circulatory levels of antioxidants and lipid peroxidation in Indian patients with generalized and localized vitiligo. Arch Dermatol Res 2009; 301:731-7. [PMID: 19488773 DOI: 10.1007/s00403-009-0964-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2009] [Revised: 05/13/2009] [Accepted: 05/15/2009] [Indexed: 12/16/2022]
Abstract
Vitiligo is an acquired skin disease, characterized by white areas on the skin due to loss of functional melanocytes. The pathogenesis of the disease is still unclear. Published data show the involvement of oxidative stress in the pathophysiology of vitiligo. A total of 30 vitiligo patients and 30 healthy controls were included in this study. We estimated serum levels of malondialdehyde (MDA), vitamins E and C, total antioxidant activity and whole blood levels of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in vitiligo patients and controls. We found significantly higher levels of MDA and significantly lower levels of SOD, GPx, vitamins C and E and total antioxidant activity in vitiligo patients compared with controls. This study is a maiden attempt to report on antioxidant parameters of both generalized/localized-type Indian vitiligo patients. Our results confirmed that oxidative stress may play an important role in the pathogenesis of vitiligo and cause melanocyte damage in vitiligo.
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