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1.
Int J Cosmet Sci ; 35(6): 546-54, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23802717

RESUMEN

OBJECTIVE: To overcome the current lack of in vitro models to specifically reproduce hormonal skin ageing in women, and in search of active ingredients with innovative efficacy claim for cosmetic skin care, we developed a cell culture-based model by simulating menopause's hormonal decline and assessed several parameters of collagen metabolism. METHODS: Human dermal fibroblasts were incubated with media containing 17ß-oestradiol, progesterone, dehydroepiandrosterone, growth hormone and insulin-like growth factor-1 at concentrations corresponding to those of non-menopausal women's sera and then of menopausal women's sera. We measured cell proliferation [by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT)], matrix metalloproteinase-1 and metalloproteinase-3 (MMPs) release (by enzyme-linked immunosorbent assay - ELISA), total collagen deposition (by Sirius red staining), types I and III collagen deposition (by ELISA), and types I and III procollagen gene expression (by real-time q-RT-PCR). RESULTS: Our results showed a significant decrease over time in cell proliferation, collagen deposition and type III/type I collagen ratio, together with an increase in MMP release, when cells were incubated in media containing sex hormones at menopausal levels. This is consistent with in vivo data from menopausal women available in the literature. Surprisingly, procollagen gene expression was only reduced within the first hours and increased afterwards when compared with non-menopausal culture conditions. CONCLUSION: Our results demonstrated that the increased procollagen synthesis with menopausal conditions was not sufficient to compensate for the MMPs' catabolic effects and/or the impaired procollagen protein maturation, resulting in a decrease in extracellular collagen content. These findings add to the overall understanding of hormone-dependent skin behaviour and highlight the suitability of this in vitro model for cosmetic actives testing aiming to underpin claims of anti-ageing efficacy, specifically for menopausal women, regarding collagen metabolism and balance of types, for maintenance of dermal mechanical properties.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Colágeno/metabolismo , Estradiol/farmacología , Fibroblastos/metabolismo , Menopausia/fisiología , Procolágeno/metabolismo , Envejecimiento de la Piel/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Cultivo de Célula , Ensayo de Inmunoadsorción Enzimática , Femenino , Fibroblastos/citología , Formazáns/análisis , Humanos , Metaloproteinasas de la Matriz/metabolismo , Persona de Mediana Edad , Procolágeno/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Sales de Tetrazolio/análisis , Adulto Joven
2.
Int J Cosmet Sci ; 34(5): 435-40, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22738140

RESUMEN

Several treatments for skin whitening are available today, but few of them are completely adequate, especially owing to the carcinogenic potential attributed to classical drugs like hydroquinone, arbutin and kojic acid. To provide an alternative and safer technology for whitening, we developed two botanical compounds originated from Brazilian biodiversity, an extract of Schinus terebinthifolius Raddi and a linoleic acid fraction isolated from Passiflora edulis oil. The whitening effect of these compounds was assessed using biochemical assays and in vitro models including cellular assays and equivalent skin. The results showed that S. terebinthifolius Raddi extract is able to reduce the tyrosinase activity in vitro, and the combination of this extract with linoleic acid is able to decrease the level of melanin produced by B16 cells cultured with melanocyte-stimulating hormone. Furthermore, melanin was also reduced in human reconstituted epidermis (containing melanocytes) treated with the compounds. The combination of the compounds may provide a synergistic positive whitening effect rather than their isolated use. Finally, we demonstrated that the performance of these mixed compounds is comparable to classical molecules used for skin whitening, as kojic acid. This new natural mixture could be considered an alternative therapeutic agent for treating hyperpigmentation and an effective component in whitening cosmetics.


Asunto(s)
Anacardiaceae/química , Epidermis/efectos de los fármacos , Ácido Linoleico/farmacología , Melaninas/antagonistas & inhibidores , Melaninas/biosíntesis , Passiflora/química , Extractos Vegetales/farmacología , Preparaciones para Aclaramiento de la Piel/farmacología , Animales , Células 3T3 BALB , Brasil , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Epidermis/enzimología , Epidermis/metabolismo , Femenino , Humanos , Técnicas In Vitro , Concentración 50 Inhibidora , Masculino , Melaninas/metabolismo , Melanocitos/efectos de los fármacos , Melanocitos/enzimología , Melanocitos/metabolismo , Melanoma Experimental/metabolismo , Ratones , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo
3.
Int J Cosmet Sci ; 33(2): 113-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20646086

RESUMEN

Oxidative stress occurs when there is an over production of free radicals and cells are not able to neutralize them by their own antioxidant mechanisms. These excess of free radicals will attack cellular macromolecules leading to cell damage, function impairment or death. Because of that, antioxidant substances have been largely used in products to offer complementary protection. In this study a new mixture of three known antioxidants (cocoa, green tea and alpha-tocopherol) was evaluated and its antioxidant protection was assessed focusing on its capacity to protect main cell macromolecules. Results have shown that it has a high antioxidant capacity by protecting lipids, DNA and proteins against oxidative damage. The antioxidant effect of the mixture on cells was also investigated and it was able to reduce oxidative stress generated by lipopolisacharide in human fibroblasts. Finally, as the mixture has proved to be highly antioxidant, its effect on cell senescence was evaluated, and it was demonstrated that fibroblasts in culture had delayed senescence when treated with these actives on a mixture. All results together provide important data about a new antioxidant mixture that uses a small amount of actives and is able to protect cell against oxidative damages in a global way.


Asunto(s)
Antioxidantes/farmacología , Cacao/química , Estrés Oxidativo/efectos de los fármacos , Piel/efectos de los fármacos , Té/química , Compuestos de Bifenilo/metabolismo , Senescencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Liposomas/metabolismo , Persona de Mediana Edad , Estrés Oxidativo/fisiología , Picratos/metabolismo , Extractos Vegetales/farmacología , Plásmidos/metabolismo , Albúmina Sérica/metabolismo , Piel/citología , Piel/metabolismo , alfa-Tocoferol/farmacología
4.
J Food Prot ; 72(2): 421-4, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19350991

RESUMEN

The aim of this work was to assess the microbiological quality of spices sold in Botucatu, São Paulo, Brazil. A total of 233 samples were analyzed for mesophilic bacteria, thermotolerant coliforms, Bacillus cereus, Staphylococcus aureus, and Salmonella. Data showed that 21 and 5.6% of these samples were not in agreement with the standards of Brazilian law, due to an excess of coliforms and to the presence of Salmonella, respectively. Black pepper and cumin exhibited the lowest microbiological quality, whereas bay leaf showed the highest quality. It was concluded that the seasonings possessed poor microbiological quality, and new alternatives should be taken in the primary production in order to improve this quality. Irradiation may also be a tool to assure the safety of these products.


Asunto(s)
Enterobacteriaceae/aislamiento & purificación , Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Salmonella/aislamiento & purificación , Especias/microbiología , Brasil , Seguridad de Productos para el Consumidor , Enterobacteriaceae/crecimiento & desarrollo , Irradiación de Alimentos , Microbiología de Alimentos , Control de Calidad , Salmonella/crecimiento & desarrollo , Especias/normas
5.
Clin Chem ; 43(9): 1744-8, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9299970

RESUMEN

Red blood cell (RBC) replacement solutions are being developed as alternatives to allogeneic RBC use in blood transfusions in the treatment of massive trauma, to achieve hemodynamic stability during elective surgery, and to increase oxygen-carrying capacity in anemia. Hemoglobin-based oxygen carrier (HBOC)-201 (Biopure Corp.) is a purified, sterile, isosmotic glutaraldehyde-polymerized bovine hemoglobin. Because this product is acellular, blood components containing this substance appear hemolyzed. This study reports on the interferences produced by the presence of HBOC-201 in a variety of clinical assays. This product was added in vitro at concentrations up to 60 g/L (6.0 g/dL) to normal human serum, plasma, or whole blood before testing for serum chemistries, coagulation profiles, and hematology and blood bank assays. In addition, a set of normal human sera containing HBOC-201 was supplemented with various therapeutic drugs and assayed for these agents. The results of these studies demonstrate that the presence of HBOC-201 in blood components does not result in significant analytical interference that would be of concern with many clinical assays at HBOC-201 concentrations encountered during routine clinical use of this RBC replacement solution in patients.


Asunto(s)
Artefactos , Bancos de Sangre , Análisis Químico de la Sangre , Pruebas de Coagulación Sanguínea/métodos , Sustitutos Sanguíneos/farmacología , Monitoreo de Drogas/métodos , Hemoglobinas/farmacología , Animales , Análisis Químico de la Sangre/métodos , Bovinos , Pruebas Diagnósticas de Rutina , Hematología/métodos , Humanos , Reproducibilidad de los Resultados
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