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3.
J Cosmet Dermatol ; 9(2): 108-16, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20618556

RESUMO

Basement membranes are thin structures present in the extracellular matrix that provide a supporting framework on which epithelial and endothelial cells reside. Type IV collagen is present ubiquitously in all basement membranes and plays an important role in cell adhesion, migration differentiation, and growth. These are especially important at the dermoepidermal junction (DEJ) in skin. A reduction in the levels of DEJ proteins occurs in photodamaged skin and especially Type IV collagen at the base of a wrinkle. In these studies, the ability of a triple peptide complex (TPC) to stimulate the production of collagen IV in human skin fibroblasts and its effects on photoaged skin was investigated. Fibroblasts, matured to represent "aged" cells, were stimulated for 72 h with the TPC as well as the three individual peptides constituting the complex, and collagen IV production by the fibroblasts was determined immunochemically. The results show that stimulation with the individual peptides at doses found in 1% (v/v) of the TPC did not result in soluble collagen IV production above levels detected by the non-stimulated cells. However, after stimulation with 1% (v/v) of the TPC, collagen IV was produced by the cells (1.4 ng/ng total protein +/- 0.4 SD, n = 5) when compared to control un-stimulated cells (0.32 ng/ng total protein +/- 0.1 SD, n = 5). This indicates that the combination of the individual peptides is necessary to synergistically stimulate collagen IV production. These findings suggest that the TPC could play a role in the strengthening of the DEJ through its ability to produce collagen IV. In order to determine whether these results translated into significant effects in vivo, we performed two studies. In the first four-week study, a double blind, placebo-controlled and fully randomized clinical study on 22 healthy Caucasian volunteers displaying moderate periorbital wrinkles, a significant reduction in wrinkle parameters determined by profilometry was observed over the 4-week period in comparison to the placebo. This result was reproduced in a 12-week monadic study which also showed improvements in expertly graded wrinkle scores. Collectively, these results effectively demonstrate the anti-aging applications of the TPC.


Assuntos
Envelhecimento , Fibroblastos/fisiologia , Peptídeos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/fisiologia , Adulto , Método Duplo-Cego , Proteínas da Matriz Extracelular/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
4.
Exp Dermatol ; 17(8): 668-74, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18318715

RESUMO

As emerging studies show that skin functioning can be improved with orally imbibed ingredients, we decided to investigate a mixture of borage oil, catechins, vitamin E and probiotics, all known for their reported effects on epidermal function, in a fermented dairy product, for the first time. Gamma-linolenic acid (GLA) and catechins bioavailability and their effects on skin functionality have not been previously investigated from a fermented dairy product. Firstly, we assessed the bioavailability of GLA and catechins mixed in a fermented dairy matrix by measuring their levels in chylomicrons and plasma samples respectively. For the GLA contained in the dairy matrix, the area under the curve and time for maximal absorption were significantly different to the same kinetic parameters compared with absorption from the free oil indicating improved oral bioavailability. However, the overall absorption of catechins over the 6-h period was identical for both product forms. These results were sufficiently promising to warrant a 24 week skin nutrition intervention study in female volunteers having dry and sensitive skin. The product improved stratum corneum barrier function compared with a control product as early as 6 weeks after the consumption which continued throughout the rest of the study. The reduction in transepidermal water loss relative to control was maintained throughout the trial despite seasonal changes. Moreover, as a result of the enhanced bioavailability, a much greater effect on skin barrier function occurred than reported previously for the individual ingredients. Nevertheless, body mass index significantly influenced various outcome measurements of this study.


Assuntos
Produtos Fermentados do Leite/química , Óleos de Plantas/administração & dosagem , Fenômenos Fisiológicos da Pele , Chá , Vitamina E/administração & dosagem , Ácido gama-Linolênico/administração & dosagem , Administração Oral , Adolescente , Adulto , Disponibilidade Biológica , Catequina/administração & dosagem , Catequina/farmacocinética , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Probióticos/administração & dosagem , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Fatores de Tempo , Ácido gama-Linolênico/farmacocinética
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