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ABSTRACT Objective: To compare and evaluate the clinical efficacy of diode laser and cryosurgery for treating melanin pigmentation of gingiva. Material and Methods: A total of twenty-five subjects with physiological gingival pigmentation on the facial aspect of both maxillary and mandibular anterior arches (50 sites), both male and female, with an average age ranging from 18-35 years, participated in the study. The sites were randomly divided into Group I: depigmentation by Laser and Group II: depigmentation by Cryosurgery. The following parameters were assessed for the evaluation of treatment results: Melanin Oral Pigmentation Index (PI), Visual Analogue Scale (VAS) for pain evaluation and Healing index (HI). The data collected was statistically evaluated. Results: On intergroup comparison, there was no statistical difference in the score from baseline (p>0.05); however, a statistically significant difference was seen at the end of 1 year (p<0.05). Moreover, 57-60% of arches showed recurrence of pigmentation in the laser group whereas; only 12.7-17% recurrence was seen in the cryosurgery group at the end of the first year. Conclusion: Treatment of gingival hyperpigmentation with laser and cryosurgery shows a marked improvement of gingival pigmentation in both groups, but the cryosurgery depigmentation sites showed more sustainability.
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Humans , Male , Female , Adolescent , Adult , Hyperpigmentation/surgery , Laser Therapy/methods , Gingival Diseases , Melanins , Visual Analog ScaleABSTRACT
ABSTRACT Background: the diagnosis of Parkinson's disease (PD) can be challenging, especially in the early stages, albeit its updated and validated clinical criteria. Recent developments on neuroimaging in PD, altogether with its consolidated role of excluding secondary and other neurodegenerative causes of parkinsonism, provide more confidence in the diagnosis across the different stages of the disease. This review highlights current knowledge and major recent advances in magnetic resonance and dopamine transporter imaging in aiding PD diagnosis. Objective: This study aims to review current knowledge about the role of magnetic resonance imaging and neuroimaging of the dopamine transporter in diagnosing Parkinson's disease. Methods: We performed a non-systematic literature review through the PubMed database, using the keywords "Parkinson", "magnetic resonance imaging", "diffusion tensor", "diffusion-weighted", "neuromelanin", "nigrosome-1", "single-photon emission computed tomography", "dopamine transporter imaging". The search was restricted to articles written in English, published between January 2010 and February 2022. Results: The diagnosis of Parkinson's disease remains a clinical diagnosis. However, new neuroimaging biomarkers hold promise for increased diagnostic accuracy, especially in earlier stages of the disease. Conclusion: Future validation of new imaging biomarkers bring the expectation of an increased neuroimaging role in the diagnosis of PD in the following years.
RESUMO Antecedentes: O diagnóstico da doença de Parkinson (DP) pode ser desafiador, principalmente nas fases iniciais da doença, embora tenha critérios clínicos atualizados e validados. Os avanços recentes em neuroimagem na DP, além do seu papel já consolidado de excluir causas secundárias e outras causas neurodegenerativas de parkinsonismo, tem contribuído para uma maior confiabilidade no diagnóstico em diferentes estágios da doença. Nesta revisão, nós destacamos os principais avanços de ressonância magnética e imagem do transportador de dopamina em auxiliar o diagnóstico de DP. Objetivo: realizar uma revisão acerca do conhecimento atual sobre o papel da ressonância magnética e imagem do transportador de dopamina no diagnóstico de doença de Parkinson. Método: Realizamos uma revisão não sistemática da literatura através da base de dados PubMed, utilizando as palavras-chave "Parkinson", "magnetic resonance imaging", "diffusion tensor", "diffusion-weighted", "neuromelanin", "nigrosome-1", "single-photon emission computed tomography", "dopamine transporter imaging". A busca foi restrita a artigos escritos em inglês, publicados entre janeiro de 2010 e fevereiro de 2022. Resultados: O diagnóstico de doença de Parkinson continua sendo um diagnóstico clínico, contudo, novos biomarcadores de neuroimagem são promissores para o aumento da acurácia diagnóstica, especialmente em fases mais precoces da doença. Conclusão: A validação futura de novos biomarcadores de imagem traz a expectativa de um maior papel da neuroimagem no diagnóstico de doença de Parkinson nos próximos anos.
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ABSTRACT: Gingival hyperpigmentation is produced by excessive melanin deposit, generating a dark gum coloring. Although it does not constitute a health issue, in some cases it usually represents an aesthetic problem that can affect psychologically, for which there are currently several treatment alternatives such as: surgery with scalpel, laser therapy, abrasion, cryosurgery, electrosurgery, among others. The aim of this literature review was to analyze the available information about gingival melanosis and the therapeutics that can be applied to improve the appearance of patients with this condition. Articles in English and Spanish, published during the period 2000-2020 in the PubMed, Medline, Scielo, Cochrane and Lilacs databases, were reviewed. It was concluded that the selection of the technique will depend on each particular case, however, the laser is the most relevant.
RESUMEN: La hiperpigmentación gingival se produce por el depósito excesivo de melanina, generando una coloración oscura de la encía. Aunque no constituye un inconveniente para la salud, en algunos casos suele representar un problema estético que puede afectar psicológicamente, por lo cual, en la actualidad existen diversas alternativas de tratamiento como: cirugía con bisturí, terapia láser, abrasión, criocirugía, electrocirugía, entre otros. El objetivo de esta revisión de la literatura fue analizar la información disponible acerca de la melanosis gingival y la terapéutica que puede ser aplicada para mejorar el aspecto de los pacientes con esta condición. Se revisaron artículos en inglés y español, publicados durante el período 2000-2020 en las bases de datos PubMed, Medline, Scielo, Cochrane y Lilacs. Se concluyó que la elección de la técnica dependerá de cada caso en particular, sin embargo, el láser es el más destacado.
Subject(s)
Hyperpigmentation/classification , Melanosis/diagnosis , Gingival DiseasesABSTRACT
Introdução: A região anterior do tórax constitui área fotoexposta que apresenta efeitos do fotodano. O microagulhamento é opção segura para rejuvenescimento dessa área, promovendo também a melhora de discromias. Objetivo: Avaliar a resposta histológica cutânea após três sessões mensais de microagulhamento para tratamento de discromias da região anterior do tórax. Métodos: Foram realizadas, três sessões mensais de microagulhamento com agulhas de 1,5mm de comprimento, e também biópsias cutâneas antes e 90 dias após o início do estudo. As amostras histológicas foram avaliadas com as colorações de HE e Fontana-Masson. O conteúdo de melanina foi mensurado com base em clusters dérmicos. Resultados: Seis pacientes com idades entre 38 e 67 anos, fototipos II-III, escala Glogau II-IV foram incluídos. Uma correlação positiva foi observada entre o tempo e o conteúdo dérmico de melanina (p= 0,029): três sessões de microagulhamento reduziram esse conteúdo no D90 em comparação com o tempo inicial (6.4 ± 1.7 MC em D0 versus 3.1 ± 0.4 em D90, p = 0.05). Três pacientes relataram melhora global da pele no D90. Conclusões: O mecanismo proposto do microagulhamento para promover clareamento inclui proliferação de fibroblastos e neocolagênese na derme superior. Esse é o primeiro estudo a avaliar histologicamente os achados associados ao clareamento da região do tórax decorrente do microagulhamento.
Introduction: The chest is a photoexposed area that shows effects of photodamage. Microneedling is a safe option for the rejuvenation of this area, also leading to improvement in dyschromias. Objective: To evaluate histologic cutaneous response after three monthly sessions of microneedling for the treatment of dyschromias on the chest. Methods: Three monthly sessions of microneedling, with 1.5mm length needles were performed, as well as skin biopsies before and 90 days after commencement of the study. Histologic samples were evaluated with H&E and Fontana-Masson stains. Melanin content was measured based on dermal clusters. Results: Six patients between 38 and 67 years of age, phototypes II-III, Glogau scale II-IV were included. A positive correlation was observed between the time and dermal content of melanin (p= 0.029): three sessions of microneedling reduced this content on D90 compared to the beginning (6.4 ± 1.7 MC on D0 versus 3.1 ± 0.4 on D90, p = 0.05). Three patients reported global skin improvement on D90. Conclusions: The proposed mechanism of microneedling to promote lightening includes fibroblast proliferation and neocollagenesis in the upper dermis. This is the first study to evaluate the histology of the findings associated to lightening of the chest due to microneedling.
Subject(s)
Skin , Histology , Melanins , Colon , NeedlesABSTRACT
Objective@#To evaluate the effect of water-soluble components of atmospheric fine particulate matter PM2.5 on proliferation, migration, tyrosinase activity and melanin content of a human melanocyte line PIG1.@*Methods@#PM2.5 was collected during haze weather in heating seasons, and processed into suspensions. PIG1 melanocytes were cultured and divided into 5 experimental groups and 1 control group. PIG1 melanocytes in the 5 experimental groups were treated with 10, 20, 50, 100 and 200 mg/L PM2.5 suspensions respectively for 48 hours, while cells in the control group were not treated with PM2.5 suspensions. In cell migration assay, there was only 1 experimental group treated with 10 mg/L PM2.5 suspensions. After treatment, methyl thiazol tetrazolium (MTT) assay, micropore filtration assay, DOPA oxidase assay and NaOH lysis method were performed to determine the cell proliferation rate, migration rate, tyrosinase activity and melanin content respectively. Statistical analysis was carried out by using t test for comparison of means of two samples, one-way analysis of variance for means of multiple samples, Student-Newman-Keuls (SNK) -q test for multiple comparisons, and linear correlation analysis for analysis of correlations.@*Results@#Compared with the control group ([100 ± 1.41]%) , the proliferation rate of PIG1 cells significantly decreased in the 20-, 50-, 100- and 200-mg/L PM2.5 groups ([93.41 ± 2.13]%, [88.31 ± 1.3557]%, [79.75 ± 1.89]%, [69.83 ± 2.50]% respectively, all P < 0.05) . Linear correlation analysis showed that the proliferation rate and tyrosinase activity of PIG1 cells decreased with the increase in PM2.5 concentrations (r = -0.98, -0.93, respectively, both P < 0.01) . After the treatment with 10 mg/L PM2.5, the migration rate of PIG1 cells significantly decreased (66.23% ± 1.11%) compared with the control group ([76.86 ± 1.81]%, t = 7.55, P < 0.01) . With the increase in PM2.5 concentrations (50-200 mg/L) , the melanin content of PIG1 cells gradually decreased (r = -0.97, P < 0.01) .@*Conclusion@#Atmospheric fine particulate matter PM2.5 can affect the normal functions of melanocytes by inhibiting their proliferation and migration, and reducing their tyrosinase activity and melanin content.
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Objective To investigate the present situation of facial melanin of construction workers in Beijing area,to discuss the relative affecting factors,and to provide theoretical basis for theoretical research on photoaging and occupational protection for construction workers.Methods A total of 157 healthy male construction workers and 61 non-construction workers in Beijing were selected to conduct a questionnaire survey on their exposure to dust,sunlight,noise and high temperature in their working environment.The occurrence of melanin in their face skin was measured by melanin index (melanin index,MI) probe.T test,Spearman rank correlation analysis and multiple logistic regression were used for statistical analysis on two independent samples.Results The exposure of construction workers to dust,sunlight,noise and high temperature was significantly higher than that of non-construction workers (P ＜0.05);the melanin score of construction workers over 40 years old was significantly higher than that of non-construction workers (P ＜0.05) and positively correlated with age (P＜0.05);the melanin of construction workers was affected by age,sunlight and noise (P＜0.05).Conclusions The melanin level of the construction workers aged over 40 is significantly higher than that of the non-construction workers in Beijing.Age,sunlight and noise are the main factors affecting the melanin level.
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Objective To evaluate the effect of water-soluble components of atmospheric fine particulate matter PM2.5 on proliferation,migration,tyrosinase activity and melanin content of a human melanocyte line PIG1.Methods PM2.5 was collected during haze weather in heating seasons,and processed into suspensions.PIG1 melanocytes were cultured and divided into 5 experimental groups and 1 control group.PIG1 melanocytes in the 5 experimental groups were treated with 10,20,50,100 and 200 mg/L PM2.5 suspensions respectively for 48 hours,while cells in the control group were not treated with PM2.5 suspensions.In cell migration assay,there was only 1 experimental group treated with 10 mg/L PM2.5 suspensions.After treatment,methyl thiazol tetrazolium (MTT) assay,micropore filtration assay,DOPA oxidase assay and NaOH lysis method were performed to determine the cell proliferation rate,migration rate,tyrosinase activity and melanin content respectively.Statistical analysis was carried out by using t test for comparison of means of two samples,one-way analysis of variance for means of multiple samples,Student-Newman-Keuls (SNK)-q test for multiple comparisons,and linear correlation analysis for analysis of correlations.Results Compared with the control group ([100 ± 1.41] ％),the proliferation rate of PIG1 cells significantly decreased in the 20-,50-,100-and 200-mg/L PM2.5 groups ([93.41 ± 2.13]％,[88.31 ± 1.3557]％,[79.75 ± 1.89]％,[69.83 ± 2.50]％ respectively,all P ＜ 0.05).Linear correlation analysis showed that the proliferation rate and tyrosinase activity of PIG 1 cells decreased with the increase in PM2.5 concentrations (r =-0.98,-0.93,respectively,both P ＜ 0.01).After the treatment with 10 mg/L PM2.5,the migration rate of PIG1 cells significantly decreased (66.23％ ± 1.11％) compared with the control group ([76.86 ± 1.81]％,t =7.55,P ＜ 0.01).With the increase in PM2.5 concentrations (50-200 mg/L),the melanin content of PIG1 cells gradually decreased (r =-0.97,P ＜ 0.01).Conclusion Atmospheric fine particulate matter PM2.5 can affect the normal functions of melanocytes by inhibiting their proliferation and migration,and reducing their tyrosinase activity and melanin content.
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BACKGROUND/OBJECTIVES: Sageretia thea is traditionally used as a medicinal herb to treat various diseases, including skin disorders, in China and Korea. This study evaluated the inhibitory effect of Sageretia thea fruit on melanogenesis and its underlying mechanisms in B16F10 mouse melanoma cells. The active chemical compounds in anti-melanogenesis were determined in Sageretia thea. MATERIALS/METHODS: Solvent fractions from the crude extract were investigated for anti-melanogenic activities. These activities and the mechanism of anti-melanogenesis in B16F10 cells were examined by determining melanin content and tyrosinase activity, and by performing western blotting. RESULTS: The n-hexane fraction of Sageretia thea fruit (HFSF) exhibited significant anti-melanogenic activity among the various solvent fractions without reducing viability of B16F10 cells. The HFSF suppressed the expression of tyrosinase and tyrosinase-related protein 1 (TRP1). The reduction of microphthalmia-associated transcription factor (MITF) expression by the HFSF was mediated by the Akt/glycogen synthase kinase 3 beta (GSK3β) signaling pathway, which promotes the reduction of β-catenin. Treatment with the GSK3β inhibitor 6-bromoindirubin-3'-oxime (BIO) restored HFSF-induced inhibition of MITF expression. The HFSF bioactive constituents responsible for anti-melanogenic activity were identified by bioassay-guided fractionation and gas chromatography-mass spectrometry analysis as methyl linoleate and methyl linolenate. CONCLUSIONS: These results indicate that HFSF and its constituents, methyl linoleate and methyl linolenate, could be used as whitening agents in cosmetics and have potential for treating hyperpigmentation disorders in the clinic.
Subject(s)
Animals , Mice , alpha-Linolenic Acid , Bleaching Agents , Blotting, Western , Camellia , China , Fruit , Gas Chromatography-Mass Spectrometry , Hyperpigmentation , Korea , Linoleic Acid , Melanins , Melanoma , Microphthalmia-Associated Transcription Factor , Monophenol Monooxygenase , Phosphotransferases , Plants, Medicinal , SkinABSTRACT
Objective To evaluate the effect of tea polyphenol epigallocatechin gallate (EGCG)on ultraviolet B (UVB)-induced skin pigmentation,transfer and degradation of melanosomes in mice,and to explore the role of autophagy in the mechanism of melanosome degradation.Methods A total of 32 ears from 16 female C57/BL6 mice were randomly and equally divided into 4 groups:acetone control group topically treated with acetone solution daily,EGCG group topically treated with 10 g/L EGCG acetone solution daily,UVB irradiation group irradiated with 500 mJ/cm2 UVB once a day and 2 hours later topically treated with acetone solution,UVB + EGCG group irradiated with 500 mJ/cm2 UVB once a day and 2 hours later topically treated with EGCG acetone solution.Ten days later,all the mice were sacrificed,and skin tissue samples were collected from the ears.Transmission electron microscopy was performed to observe ultrastructural changes of melanosomes and autophagosomes,immunohistochemical study to measure expression of protease-activated receptor 2 (PAR2) and microtubule-associated protein light chain 3 (LC3) in the epidermis,and Western blot analysis to determine the protein expression of PAR2,Rasrelated protein Rab27a and LC3 in the epidermis.Results There was a significant difference in the number of melanosomes and autophagosomes among the acetone control group,EGCG group,UVB irradiation group and UVB + EGCG group (H =12.249,13.888,respectively,both P ＜ 0.05).Compared with the acetone control group,the UVB irradiation group showed significantly increased number of melanosomes (1.85 ± 0.32 vs.1.00 ± 0.41,P ＜ 0.05)and autophagosomes (1.94 ± 0.64 vs.1.00 ± 0.46,P ＜ 0.05) in epidermal keratinocytes in mouse skin.Compared with the UVB irradiation group,the UVB + EGCG group showed significantly decreased number of melanosomes (1.30 ± 0.44,P ＜ 0.05),but significantly increased number of autophagosomes (3.03 ± 0.75,P ＜ 0.05).Immunohistochemical study showed a significant difference in the level of PAR2 in the epidermis among the 4 groups (H =18.700,P ＜ 0.05),and the expression of PAR2 was significantly lower in the UVB + EGCG group than in the UVB irradiation group (7.94 ± 4.57 vs.12.54 ± 3.07,Z =2.143,P ＜ 0.05).However,the 4 groups all showed a low level of LC3,and there was no significant difference among the 4 groups (H =5.051,P ＞ 0.05).Western blot analysis revealed significant differences in the protein expression of PAR2 and Rab27a,as well as in the LC3-Ⅱ/LC3-Ⅰ ratio,among the 4 groups (F =18.739,25.967,24.022,respectively,all P ＜ 0.05).Compared with the UVB irradiation group,the UVB + EGCG group showed significantly decreased expression of PAR2 (0.91 ± 0.54 vs.3.12 ± 0.61,P ＜ 0.05) and Rab27a (0.99 ± 0.16 vs.1.42 ± 0.07,P ＜ 0.05),but significantly increased LC3-Ⅱ/LC3-Ⅰ ratio (1.67 ± 0.08 vs.1.24 ± 0.07,P ＜ 0.05).Conclusion Topical EGCG treatment can effectively suppress UVB-induced skin pigmentation,which may be related to the inhibition of melanosome transfer and promotion of melanosome autophagy.
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Background Pigmentary glaucoma and pseudoexfoliation glaucoma are characterized by pigment dispersion in trabecular meshwork,and the dipersitional pigment probably contributes to the resistance of aqueous outflow pathway,irreversible damage of the trabecular meshwork and the remodeling abnormality of extracellular matrix.Researches determined that contents of transforming growth factor-β (TGF-β) in the aqueous humor are increased in glaucomatous eyes.However,the effects of TGF-β and fibronectin (FN) in the trabecular meshwork cells (TMCs) acted by iris pigmentary particles still are not elucidated.Objective This study was to investigate the effects of iris pigment particles on TGF-β1 and FN expression in bovine TMCs (BTMCs) cultured in vitro.Methods BTMCs were cultured in vitro by explant culture method and identified by morphological evaluation.The third generation of BTMCs were divided into normal control group and pigment group,and 100 μ1 PBS and 100 μl iris pigment suspension (final concentration of 1 × 107 particles/ml) were added into the medium for 24 hours,respectively.The expressions of TGF-β1 mRNA,FN mRNA and their proteins in the BTMCs were assayed by real-time fluorescence quantitative PCR and ELISA,respectively.Results Cultured cells grew well and showed the fusiform,polygon and dendritic like in shape,with pigmented and round nuclei.The relative expression levels of TGF-β1 mRNA and FN mRNA in the cells were 2.98±0.27 and 0.36±0.10 in the iris pigment group,which were significantly higher than 1.00±0.00 and 1.00±0.00 in the normal control group (t =12.68,10.60,both at P =0.00).The concentrations of TGF-β1 protein and FN protein in the cell suspension were (156.60±9.74)ng/L and (59.29±15.79)mg/ml in the iris pigment group,showing significant differences in comparison with (65.46 ± 14.24) ng/L and (102.10 ± 12.14)mg/mlin the normal control group (t=9.15,P=0.00;t=3.72,P=0.02).Conclusions The expression of TGF-β1 is up-regulated and that of FN is down-regulated in BTMCs cultured by iris pigment,inferring that TGF-β1 and FN participate in the pathogenesis and development of pigmentary and pseudoexfoliation glaucoma.
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Objective To study the effect of Corylin on A375 cells melanin synthesis,and explore its mechanism.Methods The cells were randomly divided into the control group, the estradiol group, and corylin group including 10-3μmol/L, 10-2μmol/L, 10-1μmol/L, 1μmol/L, 10μmol/L, 100μmol/L. Estradiol estradiol intervention group were given 10-3 mol/L. Corylin group (10-3μmol/L, 10-2μmol/L, 10-1μmol/L, 1μmol/L, 10μmol/L,100μmol/L) were given 10-3μmol/L, 10-2μmol/L, 10-1μmol/L, 1μmol/L, 10μmol/L, 100μmol/L corylin intervention. The activity of proliferation were detected by MTT, NaOH method, dopa oxidation , both melanin content and tyrosinase activity (tyrosinase, TYR). TYR, yrosinase related protein (tyrosinase related protein, TRP)-1 and TRP-2 expression levels of mRNA were determined by RT-PCR.Results Compared with the control group, 10, 100μmol/L of Corylin group cell proliferation rate significantly decreased (P<0.01). The 1μmol/L, 10-1μmol/L, 10-2μmol/L of Corylin group cell melanin content, TYR significantly decreased (P<0.01 or P<0.05). The 1μmol/L corylin group TYR (0.303 ± 0.003vs. 0.628 ± 0.012), TRP-1 (0.313 ± 0.008 vs. 0.677 ± 0.022), TRP-2 (0.456 ± 0.028vs. 0.687 ± 0.020) mRNA expression level significantly decrease (P<0.01).Conclusions The results showed that Corylin could inhibit melanin synthesis, which worked probably through inhibiting the activity of TYR and cutting the mRNA expressions of TYR,TRP-1/2.
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As a key regulator of melanogenesis, p53 controls microphthalmia-associated transcription factor (MITF) and tyrosinase expression. The anti-oxidant enzyme heme oxygenase-1 (HO-1) is induced by various forms of cellular stress and diverse oxidative stimuli. However, few studies have examined the role of HO-1 in melanogenesis. Therefore, the aim of this study was to determine the role of HO-1 in melanogenesis and the mechanism underlying this relationship. Cultures of normal human melanocytes were treated with the HO-1 inducer cobalt protoporphyrin (CoPP) or the HO-1 inhibitor zinc protoporphyrin (ZnPP). We then measured the melanin content of the cells. Additional analyses consisted of Western blotting and RT-PCR. The results showed that the cellular melanin content was increased by CoPP and decreased by ZnPP. The Western blot and RT-PCR analyses showed that CoPP increased p53, MITF and tyrosinase levels, and ZnPP reduced all of them. The knockdown of p53 by siRNA transfection was followed by large decreases in the expression levels of p53, MITF and tyrosinase at 3 h of transfection. The presence of CoPP or ZnPP had no significant increased or decreased effects on MITF and tyrosinase levels from 15 h in the siRNA transfectants. Our results suggest that HO-1 modulates melanogenesis in human melanocytes via a p53-dependent pathway.
Subject(s)
Humans , Blotting, Western , Cobalt , Heme Oxygenase-1 , Heme , Melanins , Melanocytes , Microphthalmia-Associated Transcription Factor , Monophenol Monooxygenase , RNA, Small Interfering , Transfection , ZincABSTRACT
As a key regulator of melanogenesis, p53 controls microphthalmia-associated transcription factor (MITF) and tyrosinase expression. The anti-oxidant enzyme heme oxygenase-1 (HO-1) is induced by various forms of cellular stress and diverse oxidative stimuli. However, few studies have examined the role of HO-1 in melanogenesis. Therefore, the aim of this study was to determine the role of HO-1 in melanogenesis and the mechanism underlying this relationship. Cultures of normal human melanocytes were treated with the HO-1 inducer cobalt protoporphyrin (CoPP) or the HO-1 inhibitor zinc protoporphyrin (ZnPP). We then measured the melanin content of the cells. Additional analyses consisted of Western blotting and RT-PCR. The results showed that the cellular melanin content was increased by CoPP and decreased by ZnPP. The Western blot and RT-PCR analyses showed that CoPP increased p53, MITF and tyrosinase levels, and ZnPP reduced all of them. The knockdown of p53 by siRNA transfection was followed by large decreases in the expression levels of p53, MITF and tyrosinase at 3 h of transfection. The presence of CoPP or ZnPP had no significant increased or decreased effects on MITF and tyrosinase levels from 15 h in the siRNA transfectants. Our results suggest that HO-1 modulates melanogenesis in human melanocytes via a p53-dependent pathway.
Subject(s)
Humans , Blotting, Western , Cobalt , Heme Oxygenase-1 , Heme , Melanins , Melanocytes , Microphthalmia-Associated Transcription Factor , Monophenol Monooxygenase , RNA, Small Interfering , Transfection , ZincABSTRACT
A 9-month-old male child was brought with complaints of increasing head size for 2 months, increasing lethargy and vomiting for the last 2 days. Radiology revealed a heterogeneously enhancing, globular lesion in the pineal region with hydrocephalus. Near total excision of the tumor was carried out. The histopathological examination of the lesion showed heterogenous elements in the form of mature neuroepithelial and ectomesenchymal tissue. The pathology and radiology of this unusual lesion is discussed with relevant review of literature.
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Child , Humans , Infant , Male , Cartilage , Head , Hydrocephalus , Lethargy , Melanins , Pathology , Pinealoma , VomitingABSTRACT
Objective To investigate the effect of levodopa on melanogenesis in Penicillium mameffei (PM),and to determine if melanization affects the antifungal drug susceptibility of PM.Methods A clinical isolate of PM,GXMU121011,was inoculated onto Sabouraud's dextrose agar (SDA) containing different concentrations (0.1-10 mmol/L) of levodopa at an inoculum density of 1.0 × 106 cfu/ml,or onto SDA containing 1 mmol/L levodopa at three inoculum densities (1.0 × 105,1.0 × 106,1.0 × 107 cfu/ml),and cultured at 37 ℃ for 7 days.Subsequently,melanization of PM colonies was observed.The paper-disk method was used for antifungal susceptibility testing,and the diameter of inhibition zones of itraconazole,fluconazole and amphotericin B against 8 clinical strains of PM was determined on SDA with or without levodopa.Results The melanization of PM colonies increased when the concentration of levodopa increased from 0.1 to 1.0 mmol/L,peaked when that reached 1.0 and 3.0 mmol/L,but mildly decreased when that continuously increased beyond 3.0 mmol/L,and a slight shrinkage was observed in PM colonies when that was 10.0 mmol/L.The color of colonies deepened along with the increase in inoculum density of PM.The average diameters of inhibition zones of itraconazole,fluconazole and amphotericin B against PM were all significantly lower on SDA with levodopa than on SDA without levodopa (all P ＜ 0.05).Conclusions Levodopa concentration and inoculum density both affect melanogenesis in PM.Melanization may decrease the susceptibility of PM in yeast phase to itraconazole,fluconazole and amphotericin B in vitro.
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A luz solar apresenta ondas eletromagnéticas em ampla faixa espectral, incluindo as regiões do ultravioleta (UV-C, UV-B, UV-A), visível e infravermelho. Cada região interage com a pele de forma dependente da fotofísica e da fotoquímica dos seus respectivos compostos absorvedores. A luz UV-A causa a geração de espécies reativas de oxigênio e de nitrogênio (EROs e ERNs) através da fotossensibilização de moléculas endógenas (co-enzimas de flavina, porfirinas, melaninas). Quando fotossensibilizadores produzem quantidades de EROs e ERNs maiores do que a capacidade celular de supressão destas espécies, caracteriza-se um quadro de desbalanço redox, que causa lesão em biomoléculas como os ácidos nucleicos, lipídeos e as proteínas. Essas lesões podem levar à morte celular ou a outras transformações fenotípicas e genotípicas e também estimulam a liberação de citocinas pró-inflamatórias. Com a finalidade de melhor compreender a dinâmica dos mecanismos de resposta celular após exposição ao UV-A e ao visível, nós caracterizamos inicialmente as propriedades fotofísicas da melanina e detectamos a produção de oxigênio singlete (1O2) pela fotossensibilização no visível e a supressão desta espécie excitada pela reação do oxigênio singlete com a dupla ligação reativa dos grupos indóis presentes na melanina. Estes processos também foram observados no cabelo e levaram-nos a propor um modelo que explica o efeito da luz visível na estrutura e cor dos cabelos. Demonstramos também que a feomelanina produz mais (30%) 1O2 do que a eumelanina, que sofre maior modificação na sua estrutura por fotodegradação. O efeito destes processos na pele foi estudado a nível celular. Demonstramos que células epiteliais com maior teor de melanina apresentaram maior geração de 1O2 que causa lesão no DNA e morte necro-apoptótica após irradiação com luz visível. A foto-oxidação da melanina pela luz visível nos motivou a estudar um pigmento que fosse foto-protetor não somente contra luz UV-B mas também contra luz visível. A pigmentação com Acetil-Tirosina se mostrou atóxica e protetora contra luz UV-B e visível ao contrário do pigmento com tirosina, que se mostrou protetor do UV-B mas tóxico no visível. Este efeito foi relacionado com a localização celular do polímero e não com a estrutura do mesmo. A luz UV-A, por sua vez, promove o acúmulo de lipofuscina dentro dos vacúolos autofágicos de queratinócitos da pele e que também ativa a fototoxicidade pela luz visível. A lipofuscina dentro dos vacúolos autofágicos é foto-oxidada pela luz visível, causando lesão no DNA e morte celular programada tipo II. Doses UV-A que desencadeiam a liberação de citocinas também foram caracterizados
Sunlight presents electromagnetic radiation over a wide spectral range, including the regions of ultraviolet (UV-C, UV-B, UV-A), visible and infrared. Each region interacts with skin dependending on the photophysics and photochemistry of the respective absorbing compounds. UV-A light causes the generation of reactive oxygen and nitrogen species (ROS and RNS) by photosensitization of endogenous molecules (flavin coenzymes, porphyrins, melanins). When photosensitizers produce amounts of ROS and RNS larger than the cell capacity to suppress these species, a set of redox imbalance, which damages biomolecules such as nucleic acids, lipids and proteins. This damage cause cell death and to other phenotypic and genotypic changes and also stimulates the release of proinflammatory cytokines. In order to better understand the dynamics of the mechanisms of cellular responses after exposure to UV-A and visible light, we initially characterized the photophysical properties of melanin and detected the production of singlet oxygen (1O2) by photosensitization in the visible, as well as the suppression of these excited species by reaction of singlet oxygen with the double bonds of the reactive groups presented in the melanin indols. These processes were also observed in hair and led us to propose a model that explains the effects of visible light on the structure and color of hair. We also demonstrated that pheomelanin produces more (30%) 1O2 than eumelanin, which undergoes a quick change on its structure by photodegradation. The effect of these processes in the skin was studied at the cellular level. We demonstrated that epithelial cells with larger melanin content have stronger generation of 1O2, which causes DNA damage and necro-apoptotic death after irradiation with visible light. The photo-oxidation of melanin by visible light has motivated us to study a pigment that was not only able to protect against UV-B but also against visible. Pigmentation with Acetyl-Tyrosine proved nontoxic and protective against UV-B and visible light instead of pigmentation with Tyrosine, which shielded against UV-B but showed toxicity in the visible. This effect was associated with the polymer, cell location and not with its structure. UV-A light, in turn, promotes the accumulation of lipofuscin, within autophagic vacuoles of keratinocytes also enabling phototoxicity in the visible light. The lipofuscin within the autophagic vacuoles is fotooxidized by visible light, causing DNA damage and programmed cell death type II. Linear dose of UV-A that trigger the release of cytokines were also characterized
Subject(s)
Hair , Melanins/analysis , Skin , Ultraviolet Rays/adverse effects , Biochemistry/education , Cellular Senescence/genetics , Cell Biology/education , Cell Culture Techniques/methods , Cell Death/genetics , Microscopy/statistics & numerical data , Photobiology/methodsABSTRACT
Introdução: A melanina, principal pigmento responsável pela cor da pele, sofre influência direta da exposição aos raios solares. Objetivo: Este estudo avaliou os efeitos dos raios solares nos níveis de melanina em áreas expostas e não expostas à radiação solar, considerando a sazonalidade. Métodos: Os níveis de melanina foram avaliados na fronte, região sacra e antebraço, nos períodos pós-verão e pós-inverno, através de espectrofotometria. Resultados: Os níveis de melanina após o inverno foram menores que após o verão na fronte (168,1 vs. 177), região sacra (132 vs. 140,4) e antebraço (218,7 vs. 260,4), sendo a redução estatisticamente significativa apenas no antebraço (p<0,0001). O eritema foi significativamente menor no antebraço e na fronte (p<0,0001 e p=0,002) após o inverno do que após o verão. Conclusões: A redução significativa dos níveis de melanina após o inverno no antebraço reforça a influência da sazonalidade na pigmentação da pele nas áreas de exposição solar sem uso de proteção. A pequena variação dos níveis de melanina verificado na área não exposta (sacro) confirma que a repercussão da exposição solar nos níveis de melanina é predominantemente local. O aumento da produção de melanina é diretamente relacionado à exposição local aos raios UV.
Introduction The pigment mainly responsible for the color of the skin, melanin is directly influenced by exposure to sunlight. Objective: The present study assessed the effects of solar radiation on the levels of melanin in areas exposed and not exposed to the sun, taking into consideration the seasonality of exposure. Methods: Melanin levels were evaluated on the forehead, sacral region, and forearm, in the post-summer and post-winter periods, using spectrophotometry. Results: The levels of melanin after winter were lower than those after summer in the forehead (168.1 vs. 177.0), sacral region (132.0 vs. 140.4), and forearm (218.7 vs. 260. 4), with a statistically significant reduction only in the forearm (p<0.0001).Additionally, erythema was significantly less intense in the forearm and forehead (p<0.0001 and p=0.002) after winter than after summer. Conclusion: The significant reduction of melanin levels in the forearm after winter reinforces the influence of seasonality on skin pigmentation changes to body areas exposed to the sun without protection.The small variation in the levels of melanin found in the unexposed area (sacrum) confirms that the effect of exposure to the sun on the levels of melanin is predominantly local. Increased production of melanin is directly related to local exposure to UV rays.
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Objective To estimate the effect of glycoprotein (transmembrane) nonmetastatic melanoma protein B (GPNMB) on the proliferation and migration of as well as melanogenesis in melanoma cells.Methods The expression of GPNMB was detected by immunofluorescence assay in two melanoma cell lines M14 and G-361,as well as in primary human melanocytes.Then,the three kinds of cells each were classified into three groups:experimental group treated with small interfering RNA targeting GPNMB (GPNMB-siRNA),negative control group treated with the negative control siRNA,blank control group remaining untreated.Methyl thiazolyl tetrazolium (MTT) assay,transwell invasion assay and spectrophotometry were performed to evaluate cell proliferation activity,invasion potential and melanin levels,respectively.Statistical analysis was done using Student's t test.Results GPNMB was expressed in both melanoma cells and melanocytes.The transfection with GPNMB-siRNA down-regulated the mRNA and protein expressions of GPNMB in,and markedly suppressed the proliferation and migration of,melanoma cells.In detail,the proliferative activity (expressed as the absorbence value at 570 nm) of M14 and G361 cells was reduced by 35％ and 40％ respectively,the migration activity of M14 and G361 cells by 49％ and 51％ respectively,and the melanin levels in melanocytes,M14 cells and G361 cells by 73％,82％ and 69％ respectively,in the experiment group compared with those in the blank control group.Conclusions The siRNA-mediated silencing of GPNMB could effectively inhibit the proliferation of,invasion of and melanogenesis in melanoma cells,which suggests that GPNMB plays critical roles in the initiation and progression of melanoma.
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Objective To isolate and purify melanin from yeast cells of Penicillium mameffei (PM) and to analyze its physicochemical features.Methods PM yeast cells were cultured in minimal medium containing levodopa (L-dopa) with continuous shaking at 37 ℃.Melanin was isolated from the yeast cells of PM by cell walllysing enzyme,denaturant,concentrated hot acid,and purified by sodium hydroxide and concentrated hydrochloric acid.The physicochemical properties of isolated melanin were assessed on the basis of combined chemical analysis and spectroscopic methods including ultraviolet-visible (UV-vis),Fourier transform infrared (FT-IR) and electronparamagnetic resonance (EPR).Results Similar to synthetic dopa-melanin,the isolated melanin from PM was alkali soluble,acid-resistant,insoluble in water and most organic solvents,precipitated at or below PH 3,and could be bleached by hydrogen peroxide.UV-vis spectrophotometric analysis showed that the PM-derived melanin had a typical absorption peak at 205 nm and the absorbance decreased with the increase of wavelength.FT-IR spectroscopy displayed two absorption peaks at about 3 μm and 6 μm,which was characteristic of classic melanin.EPR spectroscopy revealed that the isolated melanin contained stable free radicals.Conclusion Yeast cells of PM can use exogenous L-dopa to synthesize dopa-melanin.