Navegando por Palavras-chave "Tyrosinase"
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- ItemSomente MetadadadosAnti-wrinkle and anti-whitening effects of juca (Libidibia ferrea Mart.) extracts(Springer, 2016) Pedrosa, Tatiana do Nascimento; Barros, Aline Oliveira; Nogueira, Jessica Rodrigues; Fruet, Andrea Costa; Rodrigues, Isis Costa; Calcagno, Danielle Queiroz [UNIFESP]; Smith, Marilia de Arruda Cardoso [UNIFESP]; de Souza, Tatiane Pereira; de Moraes Barros, Silvia Berlanga; de Vasconcellos, Marne Carvalho; Araujo da Silva, Felipe Moura; Ferreira Koolen, Hector Henrique; Maria-Engler, Silvya Stuchi; Lima, Emerson SilvaSkin aging is a natural process of the human body that may be accelerated due to extrinsic causes. Libidibia ferrea, popularly known as juca, is a small tree, which possesses an abundant phenolic composition with potential antioxidant and enzymatic inhibition activities. Thus, this work aimed to investigate the anti-wrinkle and anti-whitening potentials of juca trunk bark (LFB) and pod (LFP) extracts. A comprehensive analysis of LFB and LFP phenolic composition was accomplished by means of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Effects on skin degradation were assessed by inhibitory enzymatic activity against elastase, hyaluronidase and collagenase through colorimetric assays. Cellular viability in B16F10 and primary fibroblasts were determined by Trypan Blue exclusion assay. Anti-melanogenic effects on B16F10 cells were evaluated using cellular tyrosinase, melanin content, western blot, and RT-qPCR analyses. Inhibition of matrix metalloproteinase-2 and metalloproteinase-9 (MMP-2 and MMP-9) was determined by gelatin zymography and western blot methodologies. LC-MS/MS analyses of LFB and LFP extracts allowed the characterization of 18 compounds, among them, flavonoids, phenolic acids, and secoridoids. Additionally the pod and trunk bark compositions were compared. Hyaluronidase inhibitory activity for both extracts, LFB (IC50 = 8.5 +/- 0.8 A mu g/mL) and LFP (IC50 = 16 +/- 0.5 A mu g/mL), was stronger than standard rutin (IC50 = 27.6 +/- 0.06). Pro-MMP-2 was significantly inhibited by both extracts. LFB and LFP decreased the melanin content in B16F10 due to tyrosinase inhibitory activity. L. ferrea extracts has high potential as a cosmetic ingredient due to its anti-wrinkle and depigmentant effects.
- ItemAcesso aberto (Open Access)Ativos clareadores e nonoestruturas utilizadas em formulações para manejo de hipercromias(Universidade Federal de São Paulo, 2021-07-15) Rodrigues, Julia Costa [UNIFESP]; Andréo Filho, Newton [UNIFESP]; http://lattes.cnpq.br/4715398927727906Os transtornos de hiperpigmentação são causas frequentes de procura a um consultório médico dermatológico e os responsáveis pela movimentação de milhares de dólares no mercado cosmético. O tratamento das manchas de pele oriundas destes transtornos é determinado por uma série de variáveis como etnia, cor da pele e sensibilidade aos compostos utilizados. Devido a alta demanda, os produtos com propriedades clareadoras ocupam uma posição de destaque no mercado de cosméticos e cosmecêuticos. A formulação destes produtos é desafiadora devido aos diversos fatores que devem ser controlados ao formular ativos que tendem a ser instáveis e sofrer interferências de outras substâncias da composição. Neste trabalho, busca-se elucidar os mecanismos de ação dos ativos clareadores e o impacto de diferentes nanoestruturas na melhora da estabilidade e entrega destes ativos na pele. O uso de nanopartículas é capaz de melhorar a entrega destes ativos em tais formulações.
- ItemAcesso aberto (Open Access)Vitiligo: analysis of grafting versus curettage alone, using melanocyte morphology and reverse transcriptase polymerase chain reaction for tyrosinase mRNA(Associação Paulista de Medicina - APM, 2005-01-01) Machado Filho, Carlos D'Apparecida Santos [UNIFESP]; Almeida, Fernando Augusto [UNIFESP]; Proto, Rodrigo Sestito; Landman, Gilles [UNIFESP]; Fundação do ABC Faculdade de Medicina Department of Dermatology; Universidade Federal de São Paulo (UNIFESP); Hospital do Câncer Treatment and Research CenterCONTEXT AND OBJECTIVE: Recent studies have indicated that vitiligo areas contain inactive or dormant melanocytes. Melanin synthesis is related to tyrosinase presence and indicative of active metabolic state. The aim of this study was to compare repigmentation, epidermal melanocyte distribution and tyrosinase mRNA detection through reverse transcriptase polymerase chain reaction, in tissue samples of vitiligo, before and after curettage, with or without subsequent autologous skin graft using a new method. DESIGN AND SETTING: Prospective, in the Department of Dermatology, Faculdade de Medicina do ABC, Santo André. METHODS: Two vitiligo areas were curetted. One subsequently received grafted normal sacral autologous skin, whereas the other had no further treatment. The curetted areas were examined after 30 days, to evaluate the degree of repigmentation. The melanocyte percentages and tyrosinase mRNA presence in normal skin and vitiligo areas, before and after curettage and grafting, were compared. RESULTS: Complete repigmentation was seen in all grafted areas, whereas non-grafted curetted vitiligo presented partial repigmentation. The melanocyte percentage in grafted areas was greater than in non-treated vitiligo skin (p = 0.01) and skin with curettage alone (p = 0.015). Tyrosinase mRNA was negative in 93.75% of non-treated vitiligo areas. After treatment (curettage alone or curettage and grafting), all lesions became positive for tyrosinase mRNA. CONCLUSION: Metabolically inactive or dormant melanocytes are probably present within vitiligo areas, and may be activated by exogenous or endogenous stimuli.