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1.
Artigo em Inglês | MEDLINE | ID: mdl-33969656

RESUMO

BACKGROUND: Acquired dermal melanocytosis is a heterogenous group of hyperpigmented lesioins which predominantly involve the face. AIM: The aim of this study was to study the clinical presentation and histopathology of cases with extra-facial acquired dermal melanocytosis. METHODS: Retrospective record analysis was performed between May 2016 to August 2019 to retrieve cases of extra-facial acquired dermal melanocytosis seen at the out-patient department of dermatology at the All India Institute of Medical Sciences, Jodhpur. Consecutive cases with histopathologically proven diagnosis of acquired dermal melanocytosis were included. Documentation of variation in clinical presentation and histopathologic findings was done in light of the existing literature. RESULTS: Overall, four cases of extra-facial acquired dermal melanocyosis (female:male = 1:3) were seen during the study period. The lone case on head and neck involved the ear lobule and peri-auricular area. The other three cases had involvement of the hand. The histopathology confirmed the diagnosis of dermal melanocytosis but revealed peculiar findings of angiotropic melanocytes and dilated capillaries. LIMITATIONS: Small sample size and lack of comparison with perilesional normal skin were the limitations of this study. CONCLUSION: The findings of angiotropic melanocytes may be unique to extra-facial acquired dermal melanocytosis. This might indicate interaction between dermal melanocytes and capillary endothelial cells. This finding along with dermal capillary ectasia may indicate a possible role for vascular lasers in the management of these disorders.


Assuntos
Células Endoteliais , Hiperpigmentação , Humanos , Masculino , Feminino , Estudos Retrospectivos , Melanócitos/patologia , Pele/patologia , Hiperpigmentação/diagnóstico , Hiperpigmentação/patologia
4.
Indian J Dermatol Venereol Leprol ; 88(3): 322-331, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34951940

RESUMO

BACKGROUND: Exosomes have been demonstrated to carry proteins, membrane lipids, mRNAs and microRNAs which can be transferred to surrounding cells and regulate the functions of those recipient cells. OBJECTIVES: The objective of the study was to investigate the effects of exosomes released by keratinocytes and fibroblasts on the proliferation, tyrosinase activity and melanogenesis of melanocytes. METHODS: Melanocytes, keratinocytes and fibroblasts obtained from human foreskin were cultured and exosomes secreted by keratinocytes and fibroblasts were harvested from the culture supernatants by ultracentrifugation. Each exosome fraction was divided into two parts; one part was subjected to high-throughput sequencing using an Illumina HiSeq sequencer to characterize the microRNA expression profiles, while the other part was labeled with the fluorescent dye PKH67 and was then co-cultivated with epidermal melanocytes. RESULTS: High-throughput sequencing analysis showed 168 differentially expressed microRNA within exosomes derived from keratinocytes and from fibroblasts, 97 of those being up-regulated with the other 71 down-regulated. Gene ontology analysis showed that the target genes responsible for these differentially expressed microRNAs were mainly enriched in the protein-binding region of molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that target genes regulated by differentially expressed microRNA were mainly involved in mitogen-activated protein kinase (MAPK) signaling pathway, Ras signaling pathway, cAMP signaling pathway and Wnt signaling pathway. Keratinocyte-derived exosomes were taken up by melanocytes co-cultured with them and promoted the proliferation, tyrosinase activity and melanin synthesis of those melanocytes. However, fibroblast-derived exosomes had no similar effects on melanocytes. CONCLUSION: Keratinocyte-derived exosomes but not fibroblast-derived exosomes were taken up by melanocytes in co-culture and significantly stimulated their proliferation, tyrosinase activity and melanin synthesis. Those different effects may be mainly due to the differential expression of microRNAs in exosomes derived from the different types of cells. LIMITATIONS: Electron microscopy of the obtained exosomes and in-depth study of apparently differentially expressed microRNAs were not performed.


Assuntos
Exossomos , MicroRNAs , Exossomos/genética , Exossomos/metabolismo , Fibroblastos/metabolismo , Humanos , Queratinócitos/metabolismo , Melaninas/metabolismo , Melanócitos , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Monofenol Mono-Oxigenase/farmacologia
6.
Indian J Dermatol Venereol Leprol ; 86(3): 251-261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31997793

RESUMO

BACKGROUND: Benign melanocytic neoplasms have nests of melanocytic cells and show characteristic dermoscopic features. Clinical and dermoscopic features have not been studied previously in the Indian population. AIMS: To study the clinical, epidemiological and dermoscopic patterns of benign melanocytic neoplasms. METHODS: This was a descriptive, observational, single centre study. In 107 patients with melanocytic neoplasms, 167 lesions were clinically examined and studied under the dermoscope and histopathological examination was done when indicated. The lesions were broadly divided as acquired and congenital. Five main dermoscopic patterns were seen-globular, homogenous, reticular, parallel and streaks. If there were two of these patterns in a particular lesion, it was termed 'mixed pattern'. The presence of three or more patterns was called 'multicomponent pattern'. Various other features were also observed. RESULTS: The majority of patients belonged to the third decade with a female preponderance. History of increased UV exposure and family history was significant in acquired nevi. The dermoscopic pattern progressed from predominantly reticular in junctional nevi to predominantly globular in compound nevi and lesser pigment in intradermal nevi, with more vascular structures. The congenital melanocytic nevi showed additional features of comedo- like lesions, milia- like cysts, perifollicular pigmentary changes and increased colour variation. Even though colour variation was observed in both acquired and congenital lesions, no signs of dysplasia were seen on histopathology. LIMITATIONS: A larger sample size is required, with follow up of lesions. No parallel studies in brown skinned population were found for exact comparison. CONCLUSION: Benign melanocytic proliferations are often neglected in our country. This study will help in understanding the course, clinical features and dermoscopic patterns of various benign melanocytic neoplasms, and will be a step forward towards research in our population. To the best of our knowledge, this is the first study of its kind in India.


Assuntos
Dermoscopia/métodos , Melanócitos/patologia , Melanoma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Int J Dermatol ; 58(12): 1366-1370, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30801693

RESUMO

Nevus depigmentosus (ND), also known as nevus achromicus or achromic nevus, is an uncommon congenital hypomelanosis of the skin that is often characterized as being nonprogressive and having serrated borders. It needs to be distinguished from other hypopigmented skin conditions such as nevus anemicus, hypomelanosis of Ito, Fitzpatrick patches (ash leaf spots) of tuberous sclerosis, vitiligo, indeterminate leprosy, and pigment demarcation lines. Treatment may be desired for aesthetic and possible psychosocial considerations. We review and update knowledge about ND and its simulants.


Assuntos
Hipopigmentação/diagnóstico , Nevo/diagnóstico , Diagnóstico Diferencial , Estética , Humanos , Hipopigmentação/epidemiologia , Hipopigmentação/psicologia , Hipopigmentação/terapia , Hanseníase/diagnóstico , Terapia com Luz de Baixa Intensidade , Melanócitos/patologia , Melanócitos/transplante , Nevo/epidemiologia , Nevo/psicologia , Nevo/terapia , Terapia PUVA , Fatores de Risco , Esclerose Tuberosa/diagnóstico
9.
Indian J Dermatol Venereol Leprol ; 85(3): 258-265, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30785123

RESUMO

BACKGROUND: Autologous melanocyte transplantation plays an important role in the treatment of vitiligo. OBJECTIVE: Previous studies have indicated that, compared with melanocytes growing in monolayers, melanocyte spheroids have a better survival in growth factor- and serum-deprived conditions. METHODS: Melanocyte spheroids were obtained from human epidermis by repetitive long-term trypsinization and maintained an aggregated morphology for a short period in certain conditions. RESULTS: Melanocyte spheroids were capable of growing into normal dendritic melanocytes in monolayer when they were harvested and reinoculated in 24-well plates. Immunohistochemical analysis of the melanocyte spheroids revealed that they were positive for HMB45, a melanosome-specific marker. No melanomas occurred when melanocyte spheroids were transplanted into mice. CONCLUSION: Our study provides a promising approach for melanocyte transplantation to treat vitiligo.


Assuntos
Transplante de Células/métodos , Melanócitos/ultraestrutura , Esferoides Celulares/ultraestrutura , Tripsina/administração & dosagem , Animais , Células Cultivadas , Prepúcio do Pênis/citologia , Prepúcio do Pênis/efeitos dos fármacos , Prepúcio do Pênis/ultraestrutura , Humanos , Masculino , Melanócitos/efeitos dos fármacos , Melanócitos/fisiologia , Camundongos , Camundongos Nus , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/fisiologia , Fatores de Tempo
10.
Artigo em Inglês | MEDLINE | ID: mdl-29998861

RESUMO

BACKGROUND: Accurate preparation of recipient area is a critical step in melanocyte-keratinocyte transplantation procedure for vitiligo. It is an important potential step for adaptation in the quest to achieve better results and ablative lasers potentially offer excellent precision over margin and depth control in achieving that. OBJECTIVE: To compare between the two techniques used for recipient site preparation: Er:YAG laser ablation and mechanical dermabrasion for melanocyte-keratinocyte transplantation procedure in terms of re-pigmentation achieved and adverse effects seen. METHODS: A randomized comparative trial was performed among 32 patients of stable vitiligo undergoing melanocyte-keratinocyte transplantation procedure. In Group A (n = 15), recipient site preparation was done with Er:YAG laser, and in Group B (n = 17), it was done with a motorized dermabrader. Patients of both groups were objectively assessed for re-pigmentation at 1, 3 and 6 months. RESULTS: A total of 253.696 cm2 of depigmented surface was operated upon and re-pigmentation of 125.359 cm2 (49.4%) was achieved. On comparison between two groups, no statistical difference was found with respect to total re-pigmentation achieved (Group A: 54.67% vs Group B: 48.841%, P = 0.663) and grades of re-pigmentation achieved (P = 0.796). Occurrence of adverse events was also statistically similar in both the groups. CONCLUSION: This study did not reveal any statistically different outcome (in terms of re-pigmentation and adverse effects) between the two methods of recipient site preparation - motorized dermabrasion and Er:YAG ablation. LIMITATIONS: This study is small and larger studies are needed to ascertain the benefit of Er:YAG for recipient site preparation. Future studies may also ascertain variables such as time taken to prepare the recipient area, nature of bleeding, postoperative healing, difficulties in specific area, cost of the procedure, patient comfort and ease of the surgeon, rather than comparing the re-pigmentation alone.


Assuntos
Queratinócitos/transplante , Lasers de Estado Sólido/uso terapêutico , Melanócitos/transplante , Transplante de Pele/métodos , Vitiligo/diagnóstico , Vitiligo/cirurgia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Adulto Jovem
11.
Indian J Dermatol Venereol Leprol ; 85(4): 367-373, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30516167

RESUMO

BACKGROUND: Melasma is a common acquired hyperpigmentary disorder of the sun exposed skin, especially the face. The pathogenesis is unclear but interplay between genetic factors, hormones and ultraviolet radiation is important. We have evaluated the histological characteristics of melasma and compared the findings with adjacent normal skin. METHODS: Skin biopsies were taken from both melasma and the surrounding perilesional normal skin in 50 Indian women. The sections were stained with hematoxylin and eosin, Fontana-Masson and Verhoeff-Van Gieson stains. RESULTS: Biopsy from melasma showed significant epidermal atrophy, basal cell hyperpigmentation and solar elastosis when compared with the perilesional skin. We found that the proportion of pendulous melanocytes was significantly higher in the lesional biopsy compared with the perilesional biopsy (76% vs 42%, P < 0.001). Similarly, pigmentary incontinence and features of solar elastosis were significantly higher in the lesional skin compared with the perilesional skin. CONCLUSION: The characteristic histopathological features such as epidermal atrophy, basal cell hyperpigmentation and solar elastosis suggest the role of chronic sun exposure in the pathogenesis of melasma. Presence of pendulous melanocytes is a characteristic feature of melasma. The presence of pendulous melanocytes may have prognostic implications in melasma.


Assuntos
Epiderme/patologia , Dermatoses Faciais/patologia , Melanose/patologia , Adulto , Atrofia/patologia , Biópsia , Estudos Transversais , Dermatoses Faciais/etiologia , Feminino , Humanos , Melanócitos/patologia , Melanose/etiologia , Pessoa de Meia-Idade , Luz Solar/efeitos adversos , Adulto Jovem
14.
Indian J Dermatol Venereol Leprol ; 84(3): 269-274, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29491190

RESUMO

BACKGROUND: Vitiligo is a disorder caused by the loss of the melanocyte activity on melanin pigment generation. Studies show that oxidative-stress induced apoptosis in melanocytes is closely related to the pathogenesis of vitiligo. Glutamine is a well known antioxidant with anti-apoptotic effects, and is used in a variety of diseases. However, it is unclear whether glutamine has an antioxidant or anti-apoptotic effect on melanocytes. AIMS: The aim of this study was to investigate the protective effects of glutamine on a human melanocyte oxidative stress model. METHODS: The oxidative stress model was established on human melanocytes using hydrogen peroxide. The morphology and viability of melanocytes, levels of oxidants [reactive oxygen species and malondialdehyde], levels of antioxidants [superoxide dismutase and glutathione-S-transferase], and apoptosis-related indicators (caspase-3, bax and bcl-2) were examined after glutamine exposure at various concentrations. Expressions of nuclear factor-E2-related factor 2, heme oxygenase-1, and heat shock protein 70 were detected using western blot technique after glutamine exposure at various concentrations. RESULTS: Our results demonstrate that pre-treatment and post-treatment with glutamine promoted melanocyte viability, increased levels of superoxide dismutase, glutathione-S-transferase and bcl-2, decreased levels of reactive oxygen species, malondialdehyde, bax and caspase-3, and enhanced nuclear factor-E2-related factor 2, heme oxygenase-1, and heat shock protein 70 expression in a dose dependent manner. The effect of pre-treatment was more significant than post-treatment, at the same concentration. LIMITATIONS: The mechanisms of glutamine activated nuclear factor-E2-related factor 2 antioxidant responsive element signaling pathway need further investigation. CONCLUSIONS: Glutamine enhances the antioxidant and anti-apoptotic capabilities of melanocytes and protects them against oxidative stress.


Assuntos
Antioxidantes/farmacologia , Glutamina/farmacologia , Melanócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Adolescente , Adulto , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Glutamina/uso terapêutico , Humanos , Peróxido de Hidrogênio/toxicidade , Masculino , Melanócitos/metabolismo , Estresse Oxidativo/fisiologia , Vitiligo/tratamento farmacológico , Vitiligo/metabolismo , Adulto Jovem
20.
Artigo em Inglês | MEDLINE | ID: mdl-26515837

RESUMO

BACKGROUND: An increase in number of melanocytes in the basal cell layer of the epidermis is an important feature in many disorders of hyperpigmentation. In this study, we attempted an objective evaluation of the linear density of melanocytes and keratinocytes, along with other epidermal characteristics, in periorbital hyperpigmentation using immunohistochemistry and morphometric techniques. METHODS: Melanocytes and epidermal parameters were assessed by digital morphometry in 30 newly diagnosed cases of periorbital hyperpigmentation and 14 controls from the post-auricular region. Melanocytes were labelled with the immunohistochemical stains, Melan-A and tyrosinase. We studied the linear keratinocyte density, mean linear melanocyte density, ratio of melanocytes to keratinocytes, the ratio between inner and outer epidermal length, maximum epidermal thickness and minimum epidermal thickness. RESULTS: Melan-A expression of melanocytes showed strong positive correlation (r=0.883) with the tyrosinase expression. Mean linear melanocyte density was 24/mm (range: 13-30/mm) in cases and 17/mm (13-21/mm) in controls and this difference was statistically significant (P<0.001). The mean ratio of melanocyte to keratinocyte was 0.22 (0.12-0.29) in cases and 0.16 (0.12-0.21) in controls; again, this difference was statistically significant (P<0.001). There was a mild negative correlation with linear keratinocyte density (r=-0.302) and the ratio between inner and outer epidermal length (r=-0.456). However, there were no differences in epidermal thicknesses. LIMITATIONS: There were fewer control biopsies than optimal, and they were not taken from the uninvolved periorbital region. CONCLUSION: Mean linear melanocyte density and the ratio of melanocytes to keratinocytes is increased in cases with periorbital hyperpigmentation. It is, therefore, likely that increased melanocyte density may be the key factor in the pathogenesis of periorbital hyperpigmentation.


Assuntos
Epiderme/patologia , Dermatoses Faciais/patologia , Hiperpigmentação/patologia , Melanócitos/química , Melanócitos/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Contagem de Células , Olho , Feminino , Humanos , Imuno-Histoquímica , Queratinócitos/patologia , Antígeno MART-1/análise , Masculino , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/análise , Adulto Jovem
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