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1.
J Biotechnol ; 342: 114-127, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34757047

RESUMO

Hair graying is processed by the inactivation of tyrosinase caused by the accumulation of oxidative stress and a decrease in the number of melanocytes. Therefore, the purpose of this study was to investigate the effect of SIRT1 gene knockout using the CRISPR/Cas9 system on the protein and gene expressions related to melanogenesis. In this study, the mutation in the SIRT1 knockout(KO) gene was verified by T7EI assay and Sanger DNA sequencing. Furthermore, the expression levels of SIRT1 protein and gene in KO cells were remarkably decreased compared with normal cells. Therefore, the SIRT1 gene KO cell line was successfully established for further study. The KO cells also increased SA-ß-galactosidase and decreased melanin production and the scavenging activity of hydrogen peroxide. In particular, the down-regulation of p38 and c-kit as well as the up-regulation of ERK resulted in the inactivation of MITF in the KO cells. Thus, KO cells reduced the expressions of Tyrosinase, Tyrosine hydroxylase, TRP-1 and TRP-2 through the negative modulation of MITF. Furthermore, SIRT1 gene KO cells negatively modulated antioxidant proteins such as Catalase, MnSOD, MsrA and MsrB3 through FOXO1 and Keap1. Therefore, it is suggested that SIRT1 could play a positive role in melanogenesis via MITF and FOXO1.


Assuntos
Fator de Transcrição Associado à Microftalmia , Sirtuína 1 , Sistemas CRISPR-Cas , Regulação para Baixo , Proteína 1 Associada a ECH Semelhante a Kelch , Melaninas/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Sirtuína 1/genética
2.
Hautarzt ; 72(12): 1025-1038, 2021 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-34735593

RESUMO

Optoacoustic imaging (OAB) has developed steadily in recent years. By means of partly pulsed light, in a wide variety of wavelengths, different colour carriers (chromophores) are excited to form sound waves. These in turn are detected by the newly developed systems and converted into three-dimensional images by means of various algorithms. The technique is characterised by a good ratio between contrast and penetration depth and can create macro-, meso- and microscopic images due to its scalability. Optoacoustic macroscopy broadly irradiates the area to be examined with laser light. This can produce images with a high penetration depth, but only with a moderate resolution. Clinically interesting fields of application are for example the results of sentinel lymph nodes (SLNs) examined ex vivo using macroscopic optoacoustics. Due to the ability of OAB to visualise melanin, the detection rate of metastases was superior to previous methods, but not to histology. The ability to visualise dermal and epidermal structures, especially vessels, with good resolution makes optoacoustic mesoscopy useful in the examination of inflammatory skin diseases and could contribute to the verification of the success of therapy, e.g., with biologics for psoriasis vulgaris or atopic eczema (AE), in the future. Optoacoustic microscopy, which has so far been limited mainly to preclinical in vivo research, could be used in the future to detect even finer vascular structures and their changes. The clinical possibilities of OAB seem to be of great benefit and continue to be the subject of intensive research.


Assuntos
Técnicas Fotoacústicas , Psoríase , Algoritmos , Humanos , Melaninas , Microscopia
3.
Int J Comput Assist Radiol Surg ; 16(12): 2129-2135, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34797512

RESUMO

PURPOSE: Development and performance measurement of a fully automated pipeline that localizes and segments the locus coeruleus in so-called neuromelanin-sensitive magnetic resonance imaging data for the derivation of quantitative biomarkers of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. METHODS: We propose a pipeline composed of several 3D-Unet-based convolutional neural networks for iterative multi-scale localization and multi-rater segmentation and non-deep learning-based components for automated biomarker extraction. We trained on the healthy aging cohort and did not carry out any adaption or fine-tuning prior to the application to Parkinson's disease subjects. RESULTS: The localization and segmentation pipeline demonstrated sufficient performance as measured by Euclidean distance (on average around 1.3mm on healthy aging subjects and 2.2mm in Parkinson's disease subjects) and Dice similarity coefficient (overall around [Formula: see text] on healthy aging subjects and [Formula: see text] for subjects with Parkinson's disease) as well as promising agreement with respect to contrast ratios in terms of intraclass correlation coefficient of [Formula: see text] for healthy aging subjects compared to a manual segmentation procedure. Lower values ([Formula: see text]) for Parkinson's disease subjects indicate the need for further investigation and tests before the application to clinical samples. CONCLUSION: These promising results suggest the usability of the proposed algorithm for data of healthy aging subjects and pave the way for further investigations using this approach on different clinical datasets to validate its practical usability more conclusively.


Assuntos
Aprendizado Profundo , Doença de Parkinson , Humanos , Processamento de Imagem Assistida por Computador , Locus Cerúleo , Imageamento por Ressonância Magnética , Melaninas , Doença de Parkinson/diagnóstico por imagem
4.
Appl Microbiol Biotechnol ; 105(23): 8715-8725, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34724081

RESUMO

All eukaryotes have lysosomes that contain hydrolytic enzymes, such as protease, that degrade waste materials and cellular fragments. As a cellular organelle, lysosomes function as the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself. In a previous study, melanin compounds were bleached using lysosome-related organelle extract (LOE) in which glutathione peroxidase (GPX) contributed decisively to melanin decolorization. In this study, Saccharomyces cerevisiae was engineered to overproduce GPX, which increases the melanin color reduction activity of LOE. In addition, the peroxidase activity of the recombinant yeast was measured for each compartment. In spite of the modification to overexpress the GPX protein, with the peroxidase activity of the lysosome fraction specifically higher, the overall peroxidase activity of the cells remained constant. The overexpression of GPX2 among the GPX present in S. cerevisiae increased both the melanin-decolorization activity and the peroxidase activity of LOE. These results indicate that the peroxidase activity is related to the melanin decomposition and antioxidant enzymes such as GPX. In an artificial skin tissue test, the LOE extracted from the recombinant yeast was efficient in reducing the melanin. These results confirmed the enzyme's ability to penetrate corneous tissue, and they suggest the possibility of further development as a new whitening cosmetic. KEY POINTS: • Modification of Saccharomyces cerevisiae to overexpress glutathione peroxidase (GPX). • The lysosome fraction of the recombinant strain enhanced the decolorizing function. • The LOE penetrates the skin barrier and works effectively on artificial skin tissue.


Assuntos
Melaninas , Saccharomyces cerevisiae , Glutationa , Glutationa Peroxidase/genética , Lisossomos , Extratos Vegetais , Saccharomyces cerevisiae/genética
5.
Eur J Pharm Sci ; 167: 106029, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601069

RESUMO

The co-penetration of micellar vehicles and the encapsulated drugs into the skin layers, as well as the mechanisms underlying the penetration enhancement have not been clearly elucidated. We developed licochalcone A (LA)-loaded glycyrrhiza acid (GA) (GA+LA) micelles for topical delivery of LA into the epidermis. The in vitro co-penetration, penetration pathways, mechanism of interaction between skin and the micelles, and the in vitro and in vivo whitening effect of GA+LA micelles were evaluated. Co-penetration and penetration pathways were visualized on the abdominal skin of rats model with confocal laser scanning microscopy (CLSM) using a nile blue A-labeled GA (GA-NB). We found that GA significantly increased the transport of LA into the skin predominantly via the hair follicles and GA mainly accumulated in the SC and epidermis, while LA was localized in the epidermis and dermis. Moreover, 73.4% of the LA deposited into the epidermis within 12 h and approximately 9.32% of the LA permeated across the SC in the form of entire micelles within 24 h. GA-NB+LA micelles disaggregated and accumulated in the specific skin layers, and the LA released from the carrier penetrated into deeper layers. Moreover, the GA+LA micelles promoted drug penetration via intracellular or intercellular routes by loosening the skin surface and enhancing fluidization through lipid distortion and keratin denaturation. Furthermore, GA+LA micelles exhibited synergistic whitening effect on B16 cells and UVB-exposed C57BL/6 mice. Collectively, GA micelles can enhance penetration of LA to the epidermis mainly via the hair follicles following topical application, and reduce skin pigmentation.


Assuntos
Glycyrrhiza , Micelas , Animais , Chalconas , Portadores de Fármacos , Ácido Glicirrízico , Melaninas , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Pele
6.
Molecules ; 26(20)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34684753

RESUMO

Angelica polymorpha Maxim. (APM) is used in traditional medicine to treat chronic gastritis, rheumatic pain, and duodenal bulbar ulcers. However, it is not known whether APM has epidermis-associated biological activities. Here, we investigated the effects of APM flower absolute (APMFAb) on responses associated with skin wound healing and whitening using epidermal cells. APMFAb was obtained by solvent extraction and its composition was analyzed by GC/MS. Water-soluble tetrazolium salt, 5-bromo-2'-deoxyuridine incorporation, Boyden chamber, sprouting, and enzyme-linked immunosorbent assays and immunoblotting were used to examine the effects of APMFAb on HaCaT keratinocytes and B16BL6 melanoma cells. APMFAb contained five compounds and induced keratinocyte migration, proliferation, and type IV collagen synthesis. APMFAb also induced the phosphorylations of ERK1/2, JNK, p38 mitogen-activated protein kinase, and AKT in keratinocytes. In addition, APMFAb decreased serum-induced B16BL6 cell proliferation and inhibited tyrosinase expression, melanin contents, and microphthalmia-associated transcription factor expression in α-melanocyte-stimulating hormone-stimulated B16BL6 cells. These findings demonstrate that APMFAb has beneficial effects on skin wound healing by promoting the proliferation, migration, and collagen synthesis of keratinocytes and on skin whitening by inhibiting melanin synthesis in melanoma cells. Therefore, we suggest that APMFAb has potential use as a wound healing and skin whitening agent.


Assuntos
Angelica/metabolismo , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Flores/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Melaninas/biossíntese , Melaninas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo
7.
Molecules ; 26(19)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34641503

RESUMO

Melanin is a natural pigment produced by cells to prevent damage caused by ultraviolet radiation. Previously, resveratrol was shown to reduce melanin synthesis. As a natural polyphenol with various biological activities, resveratrol occurs in a variety of beverages and plant foods, such as grapes. Therefore, we investigated whether grape extracts containing resveratrol also had the ability to regulate melanin synthesis. In this study, we used mouse B16F10 melanoma cells as a model for melanin synthesis with the melanogenesis-inducing α-melanocyte-stimulating hormone (α-MSH) as a positive control. Our results confirmed previous reports that resveratrol reduces melanin synthesis by reducing the activity of the rate-limiting enzyme tyrosinase. In contrast, the grape extract could not reduce melanin synthesis, and in fact promoted melanogenesis in the presence of α-MSH. The expression of genes related to melanin synthesis, such as tyrosinase, tyrosinase-related protein-1, tyrosinase-related protein-2, and microphthalmia-associated transcription factor, also supports these phenomena, which means that even in the presence of resveratrol, grape extract will strengthen the function of α-MSH in promoting melanin synthesis. Therefore, these results also provide a point of view for research on cosmetics.


Assuntos
Melaninas/biossíntese , Melanoma Experimental/metabolismo , Resveratrol/farmacologia , Vitis/química , alfa-MSH/farmacologia , Animais , Sobrevivência Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/genética , Melanoma Experimental/patologia , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/farmacologia , Células Tumorais Cultivadas
8.
Molecules ; 26(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34641450

RESUMO

Three new tuliposides H-J (1-3) and 11 known compounds were obtained from the methanolic extracts of the bulbs of Amana edulis for the first time. Their structures were elucidated by NMR, MS, and IR spectroscopic data, optical rotation, and Mosher's method. The melanogenesis properties of all the isolates were evaluated in B16 melanoma cells. Consequently, tributyl citrate (9) had anti-melanogenesis activity but was cytotoxic toward B16. (+)-Pyroglutamic acid (4), (+)-butyl 5-oxopyrrolidine-2-carboxylate (6), (-)-3-hydroxy-2-methylbutyrolactone (10), and 5-(hydroxymethyl)furfural (12) had increased melanin productions and tyrosinase activities. Those active components could be further studied as the candidates against melanoma and vitiligo for skin diseases or whitening/hypopigmentation for hair.


Assuntos
Glucosídeos/farmacologia , Liliaceae/química , Melanoma Experimental/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Melaninas/metabolismo , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Células Tumorais Cultivadas
9.
Molecules ; 26(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34641584

RESUMO

Despite its classification as a non-life-threatening disease, increased skin pigmentation adversely affects quality of life and leads to loss of self-confidence. Until now, there are no recommended remedies with high efficacy and human safety for hyperpigmentation. This study aimed to investigate anti-melanogenic activity and underlying mechanism of cajanin, an isoflavonoid extracted from Dalbergia parviflora Roxb. (Leguminosae) in human melanin-producing cells. Culture with 50 µM cajanin for 48-72 h significantly suppressed proliferation in human melanoma MNT1 cells assessed via MTT viability assay. Interestingly, cajanin also efficiently diminished melanin content in MNT1 cells with the half maximum inhibitory concentration (IC50) at 77.47 ± 9.28 µM. Instead of direct inactivating enzymatic function of human tyrosinase, down-regulated mRNA and protein expression levels of MITF and downstream melanogenic enzymes, including tyrosinase, TRP-1 and Dct (TRP-2) were observed in MNT1 cells treated with 50 µM cajanin for 24-72 h. Correspondingly, treatment with cajanin modulated the signaling pathway of CREB and ERK which both regulate MITF expression level. Targeted suppression on MITF-related proteins in human melanin-producing cells strengthens the potential development of cajanin as an effective treatment for human hyperpigmented disorders.


Assuntos
Isoflavonas/farmacologia , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Fator de Transcrição Associado à Microftalmia/efeitos dos fármacos , Fator de Transcrição Associado à Microftalmia/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dalbergia/química , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Hiperpigmentação/tratamento farmacológico , Interferon Tipo I/metabolismo , Oxirredutases Intramoleculares/metabolismo , Isoflavonas/química , Melaninas/biossíntese , Melanócitos/efeitos dos fármacos , Melanócitos/enzimologia , Melanócitos/metabolismo , Melanoma/enzimologia , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/farmacologia , Proteínas da Gravidez/metabolismo , Qualidade de Vida
10.
Int J Mol Sci ; 22(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34639184

RESUMO

Glycoprotein non-metastatic melanoma protein B (GPNMB) is a type I transmembrane glycoprotein that plays an important role in cancer metastasis and osteoblast differentiation. In the skin epidermis, GPNMB is mainly expressed in melanocytes and plays a critical role in melanosome formation. In our previous study, GPNMB was also found to be expressed in skin epidermal keratinocytes. In addition, decreased GPNMB expression was observed in the epidermis of lesional skin of patients with vitiligo. However, the exact role of keratinocyte-derived GPNMB and its effect on vitiligo is still unknown. In this study, we demonstrated that GPNMB expression was also decreased in rhododendrol-induced leukoderma, as seen in vitiligo. The extracellular soluble form of GPNMB (sGPNMB) was found to protect melanocytes from cytotoxicity and the impairment of melanogenesis induced by oxidative stress. Furthermore, the effect of rGPNMB was not altered by the knockdown of CD44, which is a well-known receptor of GPNMB, but accompanied by the suppressed phosphorylation of AKT but not ERK, p38, or JNK. In addition, we found that oxidative stress decreased both transcriptional GPNMB expression and sGPNMB protein expression in human keratinocytes. Our results suggest that GPNMB might provide novel insights into the mechanisms related to the pathogenesis of vitiligo and leukoderma.


Assuntos
Queratinócitos/efeitos dos fármacos , Melaninas/metabolismo , Melanócitos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Glicoproteínas de Membrana/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/metabolismo , Melanoma/patologia , Glicoproteínas de Membrana/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
11.
Int J Mol Sci ; 22(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34638544

RESUMO

Oculocutaneous albinism type 3 (OCA3) is an autosomal recessive disorder caused by mutations in the TYRP1 gene. Tyrosinase-related protein 1 (Tyrp1) is involved in eumelanin synthesis, catalyzing the oxidation of 5,6-dihydroxyindole-2-carboxylic acid oxidase (DHICA) to 5,6-indolequinone-2-carboxylic acid (IQCA). Here, for the first time, four OCA3-causing mutations of Tyrp1, C30R, H215Y, D308N, and R326H, were investigated computationally to understand Tyrp1 protein stability and catalytic activity. Using the Tyrp1 crystal structure (PDB:5M8L), global mutagenesis was conducted to evaluate mutant protein stability. Consistent with the foldability parameter, C30R and H215Y should exhibit greater instability, and two other mutants, D308N and R326H, are expected to keep a native conformation. SDS-PAGE and Western blot analysis of the purified recombinant proteins confirmed that the foldability parameter correctly predicted the effect of mutations critical for protein stability. Further, the mutant variant structures were built and simulated for 100 ns to generate free energy landscapes and perform docking experiments. Free energy landscapes formed by Y362, N378, and T391 indicate that the binding clefts of C30R and H215Y mutants are larger than the wild-type Tyrp1. In docking simulations, the hydrogen bond and salt bridge interactions that stabilize DHICA in the active site remain similar among Tyrp1, D308N, and R326H. However, the strengths of these interactions and stability of the docked ligand may decrease proportionally to mutation severity due to the larger and less well-defined natures of the binding clefts in mutants. Mutational perturbations in mutants that are not unfolded may result in allosteric alterations to the active site, reducing the stability of protein-ligand interactions.


Assuntos
Albinismo Oculocutâneo/genética , Melaninas/biossíntese , Melanócitos/metabolismo , Glicoproteínas de Membrana/genética , Oxirredutases/genética , Biologia Computacional , Humanos , Ligantes , Simulação de Acoplamento Molecular , Oxirredutases/metabolismo , Dobramento de Proteína , Estabilidade Proteica , Quinoxalinas/metabolismo
12.
Int J Mol Sci ; 22(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34639057

RESUMO

Ferula penninervis Regel & Schmalh. is a perennial plant used in Kazakh traditional folk medicine to treat epilepsy, neurosis, rheumatism, gastroduodenal ulcers, dyspepsia, wounds, abscesses or tumors. The aim of this work was to isolate series of sesquiterpene lactones from a crude methanolic root extract and investigate their in vitro cytotoxic potential against androgen-dependent prostate cancer LNCaP and epithelial prostate PNT2 cells, as well as to evaluate their melanin production inhibitory effects in murine melanoma B16F10 cells stimulated with α-melanocyte-stimulating hormone (αMSH). Two new (penninervin P and penninervin Q) and five known (olgin, laferin, olgoferin, oferin and daucoguainolactone F) guaiane-type sesquiterpene lactones were isolated with the use of a simple and fast liquid-liquid chromatography method. Olgin and laferin showed the most promising cytotoxic effects in LNCaP cells (IC50 of 31.03 and 23.26 µg/mL, respectively). Additionally, olgin, laferin, olgoferin, and oferin (10 µg/mL) potently impaired melanin release (40.67-65.48% of αMSH + cells) without influencing the viability of B16F10 cells. In summary, our findings might indicate that guaiane-type sesquiterpene lactones from F. penninervis could be regarded as promising candidates for further research in discovering new therapeutic agents with anti-prostate cancer and skin depigmentation properties.


Assuntos
Cromatografia Líquida , Ferula/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Melaninas/antagonistas & inibidores , Sesquiterpenos de Guaiano/isolamento & purificação , Sesquiterpenos de Guaiano/farmacologia , Animais , Antineoplásicos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida/métodos , Relação Dose-Resposta a Droga , Humanos , Lactonas/química , Melanoma Experimental , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Raízes de Plantas/química , Sesquiterpenos de Guaiano/química , Análise Espectral
13.
Int J Mol Sci ; 22(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34639063

RESUMO

Autophagy is involved in the degradation of melanosomes and the determination of skin color. TLR4 and tumor necrosis factor (TNF) signaling upregulates NF-kB expression, which is involved in the upregulation of mTOR. The activation of mTOR by UV-B exposure results in decreased autophagy, whereas radiofrequency (RF) irradiation decreases TLR4 and TNF receptor (TNFR) expression. We evaluated whether RF decreased skin pigmentation by restoring autophagy by decreasing the expression of TLR4 or TNFR/NF-κB/mTOR in the UV-B-irradiated animal model. UV-B radiation induced the expressions of TNFR, TLR, and NF-κB in the skin, which were all decreased by RF irradiation. RF irradiation also decreased phosphorylated mTOR expression and upregulated autophagy initiation factors such as FIP200, ULK1, ULK2, ATG13, and ATG101 in the UV-B-irradiated skin. Beclin 1 expression and the expression ratio of LC3-I to LC3-II were increased by UV-B/RF irradiation. Furthermore, melanin-containing autophagosomes increased with RF irradiation. Fontana-Masson staining showed that the amount of melanin deposition in the skin was decreased by RF irradiation. This study showed that RF irradiation decreased skin pigmentation by restoring melanosomal autophagy, and that the possible signal pathways which modulate autophagy could be TLR4, TNFR, NF-κB, and mTOR.


Assuntos
Autofagia/efeitos da radiação , Melaninas/biossíntese , Melanossomas/metabolismo , Ondas de Rádio , Pigmentação da Pele/efeitos da radiação , Raios Ultravioleta , Biomarcadores , Células Cultivadas , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Imuno-Histoquímica , NF-kappa B/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Pigmentação da Pele/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Receptor 4 Toll-Like/metabolismo
14.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3370-3376, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34658224

RESUMO

We examined the distribution of melanin during the development of the larvae of Schizothorax o'connori except the eyes with histological method. The results showed that after hatching, the appearance sequence of melanin in different organs were following an order of the outer membrane of neurocranium, the pericardial cavity and the dorsal skin, and the peritoneum and the spinal cord. Specifically, melanin appeared in the outer membrane of neurocranium around 5 DAH (days after hatching), in the pericardial cavity and the back skin at 7 DAH, and in the peritoneum and the spinal cord at 10 DAH. Melanin was found in the skin and internal organs (the outer membrane of neurocranium, the pericardial cavity, the peritoneum, the spinal cord) of S. o'connori at 10 DAH, which was mainly distributed on the back. The appearance and distribution of melanin in the postembryonic development of S. o'connori might be related to the high ultraviolet radiation. Our results could provide reference for further research on the UV protection mechanism of melanin for fish and provide theoretical support for the optimization of rearing conditions for larvae in the plateau.


Assuntos
Cyprinidae , Melaninas , Animais , Larva , Raios Ultravioleta
15.
Artigo em Inglês | MEDLINE | ID: mdl-34682308

RESUMO

Pigments are compounds of importance to several industries, for instance, the food industry, where they can be used as additives, color intensifiers, and antioxidants. As the current trend around the world is shifting to the use of eco-friendly commodities, demand for natural dyes is increasing. Melanins are pigments that are produced by several microorganisms. Pseudomonas putida ESACB 191, isolated from goat cheese rind, was described as a brown pigment producer. This strain produces a brown pigment via the synthetic Müeller-Hinton Broth. This brown compound was extracted, purified, analyzed by FTIR and mass spectrometry, and identified as eumelanin. The maximum productivity was 1.57 mg/L/h. The bioactivity of eumelanin was evaluated as the capacity for scavenging free radicals (antioxidant activity), EC50 74.0 ± 0.2 µg/mL, and as an acetylcholinesterase inhibitor, with IC50 575 ± 4 µg/mL. This bacterial eumelanin did not show cytotoxicity towards A375, HeLa Kyoto, HepG2, or Caco2 cell lines. The effect of melanin on cholesterol absorption and drug interaction was evaluated in order to understand the interaction of melanin present in the cheese rind when ingested by consumers. However, it had no effect either on cholesterol absorption through an intestinal simulated barrier formed by the Caco2 cell line or with the drug ezetimibe.


Assuntos
Queijo , Melaninas , Acetilcolinesterase , Bactérias , Células CACO-2 , Humanos
16.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684787

RESUMO

The production of α-melanocyte-stimulating hormone (α-MSH), a peptide hormone composed of 13 amino acids, is attempted by recombinant expression using E. coli as the host. To achieve this aim, a synthetic gene containing eight tandem repeats of msh gene (8msh) was designed for ribosomal synthesis of 8 α-MSH. The merit of the strategy is to diminish the peptide toxicity against the host cell and to achieve a higher production yield. Pepsin cleavage sites are introduced between the peptides for enzymatic proteolysis to obtain the monomeric peptide of α-MSH. The constructed plasmid was transformed into different strains of E. coli hosts, and E. coli XL1-Blue with gene 8msh revealed the highest yield of 8 α-MSH. Although 8 α-MSH was fractionalized in the insoluble pellets after cell lysis, pepsin cleavage was able to produce soluble α-MSH peptide, as analyzed and confirmed by mass spectrometry and peptide activity assays. The production of α-MSH was quantified using HPLC with a yield of 42.9 mg/L of LB culture. This study demonstrates the feasibility of producing α-MSH using recombinant expression of tandem repeat gene. The production procedure involves minimal post-treatment and processing and can be scaled up for industrial application.


Assuntos
alfa-MSH/biossíntese , alfa-MSH/genética , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/biossíntese , Peptídeos Catiônicos Antimicrobianos/genética , Linhagem Celular Tumoral , Escherichia coli/genética , Escherichia coli/metabolismo , Genes Sintéticos , Melaninas/biossíntese , Melanoma Experimental , Camundongos , Pepsina A/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Sequências de Repetição em Tandem/genética , alfa-MSH/administração & dosagem
18.
PLoS One ; 16(9): e0257863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34591915

RESUMO

The endophytic bacterium Burkholderia contaminans NZ was isolated from jute, which is an important fiber-producing plant. This bacterium exhibits significant growth promotion activity in in vivo pot experiments, and like other plant growth-promoting (PGP) bacteria fixes nitrogen, produces indole acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. B. contaminans NZ is considered to exert a promising growth inhibitory effect on Macrophomina phaseolina, a phytopathogen responsible for infecting hundreds of crops worldwide. This study aimed to identify the possibility of B. contaminans NZ as a safe biocontrol agent and assess its effectiveness in suppressing phytopathogenic fungi, especially M. phaseolina. Co-culture of M. phaseolina with B. contaminans NZ on both solid and liquid media revealed appreciable growth suppression of M. phaseolina and its chromogenic aberration in liquid culture. Genome mining of B. contaminans NZ using NaPDoS and antiSMASH revealed gene clusters that displayed 100% similarity for cytotoxic and antifungal substances, such as pyrrolnitrin. GC-MS analysis of B. contaminans NZ culture extracts revealed various bioactive compounds, including catechol; 9,10-dihydro-12'-hydroxy-2'-methyl-5'-(phenylmethyl)- ergotaman 3',6',18-trione; 2,3-dihydro-3,5- dihydroxy-6-methyl-4H-pyran-4-one; 1-(1,6-Dioxooctadecyl)- pyrrolidine; 9-Octadecenamide; and 2- methoxy- phenol. These compounds reportedly exhibit tyrosinase inhibitory, antifungal, and antibiotic activities. Using a more targeted approach, an RP-HPLC purified fraction was analyzed by LC-MS, confirming the existence of pyrrolnitrin in the B. contaminans NZ extract. Secondary metabolites, such as catechol and ergotaman, have been predicted to inhibit melanin synthesis in M. phaseolina. Thus, B. contaminans NZ appears to inhibit phytopathogens by apparently impairing melanin synthesis and other potential biochemical pathways, exhibiting considerable fungistatic activity.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Burkholderia/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Melaninas/biossíntese , Pirrolnitrina/biossíntese , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Agentes de Controle Biológico/farmacologia , Burkholderia/metabolismo , Técnicas de Cocultura , Produtos Agrícolas/microbiologia , Endófitos , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Indolacéticos/metabolismo , Fixação de Nitrogênio , Pirrolnitrina/farmacologia , Sequenciamento Completo do Genoma
19.
Elife ; 102021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528510

RESUMO

We previously described X-ray histotomography, a high-resolution, non-destructive form of X-ray microtomography (micro-CT) imaging customized for three-dimensional (3D), digital histology, allowing quantitative, volumetric tissue and organismal phenotyping (Ding et al., 2019). Here, we have combined micro-CT with a novel application of ionic silver staining to characterize melanin distribution in whole zebrafish larvae. The resulting images enabled whole-body, computational analyses of regional melanin content and morphology. Normalized micro-CT reconstructions of silver-stained fish consistently reproduced pigment patterns seen by light microscopy, and further allowed direct quantitative comparisons of melanin content across wild-type and mutant samples, including subtle phenotypes not previously noticed. Silver staining of melanin for micro-CT provides proof-of-principle for whole-body, 3D computational phenomic analysis of a specific cell type at cellular resolution, with potential applications in other model organisms and melanocytic neoplasms. Advances such as this in whole-organism, high-resolution phenotyping provide superior context for studying the phenotypic effects of genetic, disease, and environmental variables.


Assuntos
Imageamento Tridimensional/métodos , Melaninas , Coloração pela Prata/métodos , Microtomografia por Raio-X/métodos , Proteínas de Peixe-Zebra , Animais , Melaninas/análise , Melaninas/química , Peixe-Zebra , Proteínas de Peixe-Zebra/análise , Proteínas de Peixe-Zebra/química
20.
Life Sci ; 284: 119930, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34480938

RESUMO

AIMS: Silk fibroin (SF), a natural product from silkworms, has been used to promote anti-inflammation, induce wound healing, and reduce melanin production. However, the underlying regulatory mechanism of SF on melanin production remains unknown. The aim of this study was to investigate the distinct regulatory mechanism of SF in B16 melanoma cells by applying quantitative proteomic approach. MATERIALS AND METHODS: B16 melanoma cells were treated with PBS, KA or SF for 48 h, respectively. Cell viability, melanin content, and tyrosinase activity were examined. A label-free quantitative proteomic approach was utilized to investigate the regulatory mechanism of SF. The differentially expressed proteins and their related biological processes were subsequently identified by bioinformatics methods. Furthermore, the identified differentially expressed proteins were validated by western blot. KEY FINDINGS: Both SF and KA were able to suppress the melanin synthesis of B16 melanoma cells without appreciable toxicity; yet, SF had a distinct effect on mushroom tyrosinase activity in vitro. Moreover, quantitative proteomic approach identified 141 proteins differentially expressed only in SF/Con group. Bioinformatic analysis of these proteins revealed that oxidation-reduction process, RNA processing, fatty acid degradation, as well as melanin biosynthetic process were enriched with SF treatment. The proteins associated with melanin biosynthetic process, including microphthalmia-associated transcription factor (MITF) and tyrosinase, were down-regulated in SF group, which was confirmed by western blot. SIGNIFICANCE: SF inhibited melanin synthesis in B16 melanoma cells via down-regulation of MITF and tyrosinase expression, which provides a rationale for future utilization of SF.


Assuntos
Fibroínas/farmacologia , Melaninas/biossíntese , Melanoma Experimental/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Proteômica , Animais , Melanoma Experimental/patologia , Camundongos , Pironas/farmacologia , Reprodutibilidade dos Testes
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