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Wu X, Yang Y, Xiang L, Zhang C. The fate of melanocyte: Mechanisms of cell death in vitiligo. Pigment Cell Melanoma Res 2020; 34:256-267. [PMID: 33346939 DOI: 10.1111/pcmr.12955] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 12/10/2020] [Indexed: 01/20/2023]
Abstract
Loss of melanocytes (MCs) is the most notable feature of vitiligo. Hence, it is critical to clarify the mechanisms of MC destruction in vitiligo. Apoptosis is most widely studied cell death pathways in vitiligo. In addition, the other two forms of cell death, conventional necrosis and autophagy seem to be involved in the death of vitiligo MCs under certain situations. Moreover, new types of regulated cell death including necroptosis, pyroptosis, and ferroptosis may also participate in the pathogenesis of vitiligo. Anoikis is likely to be connected with the death of detached MCs, which is provoked specifically by loss of anchorage. Primary phagocytosis, later called phagoptosis can execute death of viable cells, probably partly responsible for the loss of MCs in vitiligo. In this review, we aim to summarize the latest insights into various forms of MC death in vitiligo and discuss the corresponding mechanisms.
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Affiliation(s)
- Xiuyi Wu
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, PR China
| | - Yiwen Yang
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, PR China
| | - Leihong Xiang
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, PR China
| | - Chengfeng Zhang
- Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, PR China
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2
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Zhao C, Wang D, Wang X, Mao Y, Xu Z, Sun Y, Mei X, Song J, Shi W. Down-regulation of exosomal miR-200c derived from keratinocytes in vitiligo lesions suppresses melanogenesis. J Cell Mol Med 2020; 24:12164-12175. [PMID: 32918341 PMCID: PMC7579706 DOI: 10.1111/jcmm.15864] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/01/2020] [Accepted: 08/21/2020] [Indexed: 12/13/2022] Open
Abstract
Vitiligo is a refractory disfiguring skin disease. However, the aetiology and pathogenesis of vitiligo have not been fully defined. Previous studies have shown that exosomes from normal human keratinocytes improve melanogenesis by up‐regulating the expression of melanogenesis‐related proteins. Several microRNAs (miRNAs) have been demonstrated to be effective in modulating melanogenesis via exosomes. In the present study, it was found that the effect of exosomes derived from keratinocytes in vitiligo lesions in regulating melanin synthesis is weakened. Furthermore, miR‐200c was detected to be significantly down‐regulated in exosomes from keratinocytes in vitiligo lesions. In addition, miR‐200c enhanced the expression of melanogenesis‐related genes via suppressing SOX1 to activate β‐catenin. In conclusion, our study revealed that the effect of exosomes secreted by keratinocytes in vitiligo lesions exhibited a weaker capacity in promoting melanogenesis of melanocytes. Moreover, the expression of miR‐200c, which mediates melanogenesis in exosomes secreted by keratinocytes in vitiligo lesions, is down‐regulated, which may be one of the pathogenesis in vitiligo. Therefore, keratinocyte‐derived exosomal miR‐200c may be a potential target for the treatment of vitiligo.
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Affiliation(s)
- Chaoshuai Zhao
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Dongliang Wang
- Department of Nuclear Medicine, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xin Wang
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yaqi Mao
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ziqian Xu
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yue Sun
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xingyu Mei
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jun Song
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Weimin Shi
- Department of Dermatology, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
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3
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Bellei B, Picardo M. Premature cell senescence in human skin: Dual face in chronic acquired pigmentary disorders. Ageing Res Rev 2020; 57:100981. [PMID: 31733332 DOI: 10.1016/j.arr.2019.100981] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/16/2019] [Accepted: 11/07/2019] [Indexed: 01/10/2023]
Abstract
Although senescence was originally described as an in vitro acquired cellular characteristic, it was recently recognized that senescence is physiologically and pathologically involved in aging and age-related diseases in vivo. The definition of cellular senescence has expanded to include the growth arrest caused by various cellular stresses, including DNA damage, inadequate mitochondria function, activated oncogene or tumor suppressor genes and oxidative stress. While senescence in normal aging involves various tissues over time and contributes to a decline in tissue function even with healthy aging, disease-induced premature senescence may be restricted to one or a few organs triggering a prolonged and more intense rate of accumulation of senescent cells than in normal aging. Organ-specific high senescence rate could lead to chronic diseases, especially in post-mitotic rich tissue. Recently, two opposite acquired pathological conditions related to skin pigmentation were described to be associated with premature senescence: vitiligo and melasma. In both cases, it was demonstrated that pathological dysfunctions are not restricted to melanocytes, the cell type responsible for melanin production and transport to surrounding keratinocytes. Similar to physiological melanogenesis, dermal and epidermal cells contribute directly and indirectly to deregulate skin pigmentation as a result of complex intercellular communication. Thus, despite senescence usually being reported as a uniform phenotype sharing the expression of characteristic markers, skin senescence involving mainly the dermal compartment and its paracrine function could be associated with the disappearance of melanocytes in vitiligo lesions and with the exacerbated activity of melanocytes in the hyperpigmentation spots of melasma. This suggests that the difference may arise in melanocyte intrinsic differences and/or in highly defined microenvironment peculiarities poorly explored at the current state of the art. A similar dualistic phenotype has been attributed to intratumoral stromal cells as cancer-associated fibroblasts presenting a senescent-like phenotype which influence the behavior of neoplastic cells in either a tumor-promoting or tumor-inhibiting manner. Here, we present a framework dissecting senescent-related molecular alterations shared by vitiligo and melasma patients and we also discuss disease-specific differences representing new challenges for treatment.
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Affiliation(s)
- Barbara Bellei
- Laboratory of Cutaneous Physiopathology and Integrated Center for Metabolomics Research, San Gallicano Dermatological Institute, IRCCS, Rome, Italy.
| | - Mauro Picardo
- Laboratory of Cutaneous Physiopathology and Integrated Center for Metabolomics Research, San Gallicano Dermatological Institute, IRCCS, Rome, Italy
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4
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Stowman AM. Educational Case: Vitiligo. Acad Pathol 2019; 6:2374289519888719. [PMID: 31828219 PMCID: PMC6886271 DOI: 10.1177/2374289519888719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/21/2019] [Accepted: 10/12/2019] [Indexed: 11/16/2022] Open
Abstract
The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.1.
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Affiliation(s)
- Anne M Stowman
- Department of Pathology and Laboratory Medicine, University of Vermont Health System and The Robert Larner MD College of Medicine at the University of Vermont, Burlington, VT, USA
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Kovacs D, Bastonini E, Ottaviani M, Cota C, Migliano E, Dell’Anna ML, Picardo M. Vitiligo Skin: Exploring the Dermal Compartment. J Invest Dermatol 2018; 138:394-404. [DOI: 10.1016/j.jid.2017.06.033] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 06/21/2017] [Accepted: 06/27/2017] [Indexed: 11/28/2022]
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Singh A, Gotherwal V, Junni P, Vijayan V, Tiwari M, Ganju P, Kumar A, Sharma P, Fatima T, Gupta A, Holla A, Kar HK, Khanna S, Thukral L, Malik G, Natarajan K, Gadgil CJ, Lahesmaa R, Natarajan VT, Rani R, Gokhale RS. Mapping architectural and transcriptional alterations in non-lesional and lesional epidermis in vitiligo. Sci Rep 2017; 7:9860. [PMID: 28852211 PMCID: PMC5575244 DOI: 10.1038/s41598-017-10253-w] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 08/08/2017] [Indexed: 01/31/2023] Open
Abstract
In vitiligo, chronic loss of melanocytes and consequent absence of melanin from the epidermis presents a challenge for long-term tissue maintenance. The stable vitiligo patches are known to attain an irreversible depigmented state. However, the molecular and cellular processes resulting in this remodeled tissue homeostasis is unclear. To investigate the complex interplay of inductive signals and cell intrinsic factors that support the new acquired state, we compared the matched lesional and non-lesional epidermis obtained from stable non-segmental vitiligo subjects. Hierarchical clustering of genome-wide expression of transcripts surprisingly segregated lesional and non-lesional samples in two distinct clades, despite the apparent heterogeneity in the lesions of different vitiligo subjects. Pathway enrichment showed the expected downregulation of melanogenic pathway and a significant downregulation of cornification and keratinocyte differentiation processes. These perturbations could indeed be recapitulated in the lesional epidermal tissue, including blunting of rete-ridges, thickening of stratum corneum and increase in the size of corneocytes. In addition, we identify marked increase in the putrescine levels due to the elevated expression of spermine/spermidine acetyl transferase. Our study provides insights into the intrinsic self-renewing ability of damaged lesional tissue to restore epidermal functionality in vitiligo.
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Affiliation(s)
- Archana Singh
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Vishvabandhu Gotherwal
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India.,Academy of Scientific and Innovative Research, New Delhi, India
| | - Päivi Junni
- Turku Centre for Biotechnology, University of Turku and ÅboAkademi University, Turku, Finland
| | - Vinaya Vijayan
- CSIR-National Chemical Laboratory, Chemical Engineering Division, Pune, India
| | - Manisha Tiwari
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Parul Ganju
- National Institute of Immunology, ArunaAsaf Ali Marg, New Delhi, India
| | - Avinash Kumar
- National Institute of Immunology, ArunaAsaf Ali Marg, New Delhi, India
| | - Pankaj Sharma
- Department of Dermatology, Post Graduate Institute for Medical Education and Research (PGIMER), Dr. Ram Manohar Lohia Hospital, New Delhi, India
| | - Tanveer Fatima
- Department of Dermatology, Post Graduate Institute for Medical Education and Research (PGIMER), Dr. Ram Manohar Lohia Hospital, New Delhi, India
| | - Aayush Gupta
- Department of Dermatology, Dr. D. Y. Patil Medical College, Pimpri, Pune, India
| | - Ananthaprasad Holla
- MelanoSite, Center for Advanced Vitiligo Treatment and Collaborative Pigment Cell Research, New Delhi, India
| | - Hemanta K Kar
- Department of Dermatology, Post Graduate Institute for Medical Education and Research (PGIMER), Dr. Ram Manohar Lohia Hospital, New Delhi, India
| | - Sangeeta Khanna
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Lipi Thukral
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | - Garima Malik
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India
| | | | - Chetan J Gadgil
- CSIR-National Chemical Laboratory, Chemical Engineering Division, Pune, India
| | - Riitta Lahesmaa
- Turku Centre for Biotechnology, University of Turku and ÅboAkademi University, Turku, Finland
| | - Vivek T Natarajan
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India. .,Academy of Scientific and Innovative Research, New Delhi, India.
| | - Rajni Rani
- National Institute of Immunology, ArunaAsaf Ali Marg, New Delhi, India.
| | - Rajesh S Gokhale
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi, India. .,National Institute of Immunology, ArunaAsaf Ali Marg, New Delhi, India. .,CSIR-National Chemical Laboratory, Chemical Engineering Division, Pune, India. .,Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India.
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7
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Fawzy MM, El Maadawi ZM, Hegazy RA, El Fatah NSA. Vitiligo - The story from within: A transmission electron microscopic study before and after narrow-band ultraviolet B. Ultrastruct Pathol 2016; 40:265-75. [PMID: 27594347 DOI: 10.1080/01913123.2016.1218987] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Melanocyte loss is the main feature of vitiligo, but evidence refers to pathological multiplayers. Transmission electron microscopy was utilized to further explore vitiligo before and after narrow-band ultraviolet B (NB-UVB) therapy. Skin biopsies were retrieved from lesional and perilesional skin and compared to normal control skin. Sections were examined for melanocytes and keratinocytes and the number of melanosomes and thickness of basal lamina were measured. In lesional skin, keratinocytes revealed two types of degeneration with a significant increase in the mean thickness of basal lamina and decrease in the number of melanosomes. After treatment, lesional and perilesional skin showed variable ultrastructural features.
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Affiliation(s)
- Marwa M Fawzy
- a Department of Dermatology , Faculty of Medicine, Cairo University , Cairo , Egypt
| | - Zeinab M El Maadawi
- b Department of Histology & Cell Biology , Faculty of Medicine, Cairo University , Cairo , Egypt
| | - Rehab A Hegazy
- a Department of Dermatology , Faculty of Medicine, Cairo University , Cairo , Egypt
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8
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Attili VR, Attili SK. Segmental and generalized vitiligo: both forms demonstrate inflammatory histopathological features and clinical mosaicism. Indian J Dermatol 2013; 58:433-8. [PMID: 24249893 PMCID: PMC3827513 DOI: 10.4103/0019-5154.119949] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Segmental vitiligo (SV) and generalized vitiligo (GV) are perceived to evolve by different mechanisms, the former with unspecified neural mechanisms and the latter by melanocyte specific autoimmune mechanisms. However, the two diverse mechanisms are difficult to reconcile in cases of "mixed vitiligo". To test the possibility of a common pathogenesis, we reviewed clinical and histopathological features of SV and GV. MATERIALS AND METHODS As part of an ongoing histopathological study on vitiligo and vitiligo like lesions, over a 10 year period from 2002 to 2011, biopsies were taken routinely from evolving or recently evolved lesions. 50 cases of SV with quasi-dermatomal distribution and 154 cases of GV were identified and the clinical and histopathological features were compared. RESULTS Mild clinical inflammation was recorded in 33 of 154 GV cases but, none among 50 SV had such features. In addition to bilateral symmetrical involvement, mirror image lesions with unusual segmentation were observed in nine cases of GV. SV with a few bilateral lesions (4) and GV with quasi-dermatomal lesions (3), i.e., mixed vitiligo, were included in their corresponding groups for analytical purposes. Focal lichenoid inflammation of varying degrees around epidermal/adnexal melanocytes was identified as a common feature in evolving lesions of both SV (78%) and GV (70%). CONCLUSIONS SV and GV demonstrated a similar inflammatory histopathological spectrum. "Segmentation/mosaicism", identified for the first time in GV is another unifying factor. Cutaneous mosaicism harboring fragile melanocyte populations, which are susceptible to external as well as auto-inflammatory mechanisms, is an attractive hypothesis to pursue in the causation of vitiligo.
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Affiliation(s)
- Venkat Ratnam Attili
- Visakha Institute of Skin and Allergy, Marripalem, Visakhapatnam, Andhra Pradesh, India
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9
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Yu R, Huang Y, Zhang X, Zhou Y. Potential role of neurogenic inflammatory factors in the pathogenesis of vitiligo. J Cutan Med Surg 2012; 16:230-44. [PMID: 22784515 DOI: 10.1177/120347541201600404] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Vitiligo is a highly complex multifactorial condition of the skin that has an unclear mechanism of pathogenesis. OBJECTIVE This review summarizes the role of various neurogenic inflammatory factors significantly upregulated in vitiligo. METHODS A literature review was conducted of all pertinent data regarding neuropeptides that are altered in vitiligo and their possible role in the destruction of melanocytes. RESULTS The close associations between the skin, immune system, and nervous system, along with specific changes demonstrated in vitiligo patients, support a pathogenic mechanism of vitiligo that involves neuroimmunologic factors, the release of which can be governed by mental stress. CONCLUSION Neuropeptides and nerve growth factors are critical regulators of emotional response and may precipitate the onset and development of vitiligo in certain predisposed individuals. More studies are required to investigate whether a direct link exists between genetics, mental stress, and neurogenic factors in vitiligo.
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Affiliation(s)
- Richard Yu
- Molecular Medicine Laboratory and Chieng Genomics Centre, Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC
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10
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Anbar TS, El-Sawy AE, Attia SK, Barakat MT, Moftah NH, El-Ammawy TS, Abdel-Rahman AT, El-Tonsy MH. Effect of PUVA therapy on melanocytes and keratinocytes in non-segmental vitiligo: histopathological, immuno-histochemical and ultrastructural study. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2011; 28:17-25. [DOI: 10.1111/j.1600-0781.2011.00631.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tag S. Anbar
- Dermatology Department; Al-Minya University; Al-Minya; Egypt
| | | | - Sameh K. Attia
- Dermatology Department; Al-Minya University; Al-Minya; Egypt
| | | | - Noha H. Moftah
- Dermatology Department; Al-Minya University; Al-Minya; Egypt
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Prignano F, Ricceri F, Bianchi B, Guasti D, Bonciolini V, Lotti T, Pimpinelli N. Dendritic cells: ultrastructural and immunophenotypical changes upon nb-UVB in vitiligo skin. Arch Dermatol Res 2010; 303:231-8. [PMID: 21174109 DOI: 10.1007/s00403-010-1109-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 11/29/2010] [Accepted: 11/30/2010] [Indexed: 11/28/2022]
Abstract
The role of dendritic cells in vitiligo is still unclear. Few studies have provided contradictory results about their quantitative variation and no data exist concerning their immunophenotypical distribution in diseased skin. The purpose of our study was to analyze the presence, the distribution, the immunophenotypical markers and the effects of nb-UVB therapy on dendritic cells in non-lesional, perilesional, and lesional vitiligo skin. Punch-biopsies of 6 mm were taken from lesional, perilesional, and non-lesional skin of 12 patients affected by non-segmental vitiligo, treated with nb-UVB. An immunohistochemical and an ultrastructural analysis were performed. Immunohistochemical and ultrastructural analysis showed both quantitative and qualitative modifications of Langerhans cells. Nb-UVB therapy, one of the most effective treatments for the disease, was able to reduce the Langerhans cells number and to redistribute main dendritic subsets. This study underlines the importance of dendritic cells, Langerhans cells in particular, in non-segmental vitiligo, in its pathogenesis and in its better therapeutical approach.
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Affiliation(s)
- Francesca Prignano
- Division of Clinical, Preventive and Oncology Dermatology, Department of Critical Care Medicine and Surgery, University of Florence, Italy.
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12
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Prignano F, Pescitelli L, Becatti M, Di Gennaro P, Fiorillo C, Taddei N, Lotti T. Ultrastructural and functional alterations of mitochondria in perilesional vitiligo skin. J Dermatol Sci 2009; 54:157-67. [DOI: 10.1016/j.jdermsci.2009.02.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2008] [Revised: 01/09/2009] [Accepted: 02/05/2009] [Indexed: 10/21/2022]
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Attili VR, Attili SK. Lichenoid inflammation in vitiligo – a clinical and histopathologic review of 210 cases*. Int J Dermatol 2008; 47:663-9. [DOI: 10.1111/j.1365-4632.2008.03672.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Nevus depigmentosus is a congenital disorder characterized by a nonprogressive hypopigmented lesion, which may not be apparent at birth. Thus, it is sometimes difficult to differentiate vitiligo from nevus depigmentosus only by clinical features. We postulated that the histologic changes in lesional and perilesional skin might be different in the 2 conditions. We took biopsies from both lesional and perilesional skin of 100 cases of vitiligo to assess the number of melanocytes, the amount of melanin, dermal inflammatory infiltrate, and other changes. We compared them with 30 cases of nevus depigmentosus. Histologically, lesions of vitiligo showed more basal hypopigmentation and dermal inflammation than perilesional normal skin. With Fontana-Masson staining, 16% of cases of vitiligo showed the presence of melanin. The ratio of pigmented area to epidermal area was 0.06% in vitiligo, whereas 17% in perilesional normal skin and 8.9% in nevus depigmentosus. In NKI/beteb staining, 12% of vitiligo showed the presence of melanocytes, and their average number was 7.68 per square millimeter. The number of melanocytes was also decreased in nevus depigmentosus but not as much as in vitiligo. We also confirmed the presence of melanocytes in 1 of 3 cases of vitiligo by electron microscopy. In conclusion, there are a few melanocytes and melanin in some cases of vitiligo. Therefore, the diagnosis of vitiligo should be made considering these points.
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15
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Bondanza S, Maurelli R, Paterna P, Migliore E, Giacomo FD, Primavera G, Paionni E, Dellambra E, Guerra L. Keratinocyte cultures from involved skin in vitiligo patients show an impaired in vitro behaviour. ACTA ACUST UNITED AC 2007; 20:288-300. [PMID: 17630962 DOI: 10.1111/j.1600-0749.2007.00385.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Vitiligo depigmentation is considered a consequence of either melanocyte disappearance or loss of functioning melanocytes in the involved areas. However, it has been reported that keratinocytes in involved vitiligo skin are damaged too. Based on this evidence, we evaluated the in vitro behaviour, in life span cultures, of involved and uninvolved vitiligo keratinocytes and their expression of proliferation, differentiation and senescence markers. An additional purpose was to investigate whether vitiligo keratinocytes from depigmented skin are able to sustain survival and growth of normal melanocytes (when added in co-culture experiments), as normal human keratinocytes manage to do. Our results demonstrate that almost all involved vitiligo keratinocytes have a shorter life span in vitro than the uninvolved cells and all of them do not maintain melanocytes in culture in a physiological ratio. Modification of proliferation and senescence marker expression also occurs. Indeed, we detected low initial expression levels of the senescence marker p16 in involved vitiligo keratinocytes, despite their shorter in vitro life span, and increased expression of proliferating cell nuclear antigen and p53. This preliminary analysis of a small number of in vitro cultured vitiligo keratinocytes suggests an impaired senescence process in lesional vitiligo keratinocytes and attempts to regulate it.
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Affiliation(s)
- Sergio Bondanza
- Tissue Engineering and Cutaneous Physiopathology Laboratory, Istituto Dermopatico dell'Immacolata-IRCCS, Rome, Italy
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16
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Dell'anna ML, Picardo M. A review and a new hypothesis for non-immunological pathogenetic mechanisms in vitiligo. ACTA ACUST UNITED AC 2006; 19:406-11. [PMID: 16965269 DOI: 10.1111/j.1600-0749.2006.00333.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Vitiligo is an acquired depigmenting disorder characterized by the loss of functioning epidermal melanocytes because of multifactorial and overlapping pathogenetic mechanisms. Besides the immunological approach, the study of the metabolic deregulations leading to toxic damage of the melanocytes appears to be more and more relevant. It was only last year that the first in vitro evidence supporting the link and the temporal sequence between the immune response and the cellular oxidative stress was provided, suggesting that the intrinsic damage of the melanocytes is primitive. What can be the guide line of the multiple altered metabolisms? A compromised membrane could render the cell sensitive to the external and internal agents differently, usually ineffective on the cell activity and survival. The primitive altered arrangement of the lipids may affect the transmembrane housing of proteins with enzymatic or receptorial activities, also conferring on them antigenic properties.
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Affiliation(s)
- Virendra N Sehgal
- Dermato-Venereology (Skin/VD) Center, Sehgal Nursing Home, Panchwati, Azadpur, Delhi, India.
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Abstract
Leukoderma in association with congenital melanocytic nevi is a rare phenomenon; nevertheless several reports have been published in the literature. We present a 15-year-old boy born with a pigmented lesion on the lower and upper eyelid diagnosed as a congenital divided nevus of the eyelid. At the age of 13, he developed a depigmented area around the nevus and was diagnosed at first as having a halo nevus in a congenital nevus. Over the next two years, an area of depigmentation appeared around the contralateral eye. At the present time, the patient has bilateral periocular depigmentation. Congenital divided nevus of the eyelid is a rare lesion, and no reports have been published to date of depigmentation in association with this lesion. Our patient presented with depigmentation around the nevus as in a halo nevus phenomenon, although at the present time, the depigmented area has a symmetric periocular distribution, and therefore can be labeled as periocular vitiligo associated with a congenital divided nevus.
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Affiliation(s)
- A Guerra-Tapia
- Dermatology Department, 12 de Octubre Hospital, Madrid, Spain
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Loquai C, Metze D, Nashan D, Luger TA, Böhm M. Confetti-like lesions with hyperkeratosis: a novel ultraviolet-induced hypomelanotic disorder? Br J Dermatol 2005; 153:190-3. [PMID: 16029349 DOI: 10.1111/j.1365-2133.2005.06634.x] [Citation(s) in RCA: 10] [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
Confetti leucoderma can occur in a variety of unrelated skin disorders and is often a diagnostic challenge. We describe a 33-year-old man with a history of mycosis fungoides and vitiligo. He developed disseminated 1-2-mm round-shaped leucodermic lesions 6 months after psoralen photochemotherapy and 12 months after systemic therapy with interferon. The skin lesions had a discrete hyperkeratotic scale. Multiple skin biopsies and immunohistochemical studies showed lamellar orthohyperkeratosis, papillomatosis, hypomelanotic keratinocytes but a normal number of melanocytes. Langerhans cells, in contrast, were reduced in lesional skin. Electron microscopy disclosed only a few type I and II melanosomes in lesional melanocytes, while keratinocytes were largely devoid of any melanosomes. This constellation of clinical, immunohistochemical and ultrastructural findings has not been reported before and distinguishes our case from leucoderma punctatum, idiopathic guttate hypomelanosis and disseminated hypopigmented keratoses. We suggest that the skin lesions observed in our patient represent an unusual response to ultraviolet damage to melanocytes followed by reactive epidermal hyperkeratosis.
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Affiliation(s)
- C Loquai
- Department of Dermatology, University of Münster, Von Esmarch-Str. 58, D-48149 Münster, Germany
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