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1.
J Biosci Bioeng ; 108(1): 41-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19577190

RESUMO

Screening of bacterial whole cells was performed for regioselective hydroxylation of daidzein and genistein. Among the strains examined, Streptomyces avermitilis MA-4680 showed high ortho-dihydroxylation activity to produce 3',4',7-trihydroxyisoflavone and 3',4',5,7-tetrahydroxyisoflavone from daidzein (4',7-dihydroxyisoflavone) and genistein (4',5,7-trihydroxyisoflavone), respectively. Using 100 mg cells (wet wt.) and 1% (v/v) Triton X100 in 1 ml of total reaction volume, where 100 microl of the substrate solution (0.5 mM in 10% (v/v) mixed solvent of DMSO:MeOH = 3:7) was added to 900 microl of potassium phosphate buffer (100 mM, pH 7.2), a 16% molar conversion yield of 3',4',7-trihydroxyisoflavone was obtained from 0.5 mM daidzein after 24 h of reaction time at 28 degrees C and 200 rpm. Ketoconazole significantly (ca. 90%) inhibited the ortho-hydroxylation activity of daidzein, suggesting that cytochrome P450 enzymes putatively play roles in regiospecific daidzein hydroxylation. The analysis of the reaction products was determined by gas chromatography/mass spectrometry (GC/MS) and (1)H NMR.


Assuntos
Isoflavonas/metabolismo , Streptomyces/metabolismo , Biotransformação , Inibidores das Enzimas do Citocromo P-450 , Detergentes/química , Inibidores Enzimáticos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Hidroxilação , Isoflavonas/farmacocinética , Cinética , Espectroscopia de Ressonância Magnética
2.
J Cosmet Sci ; 59(5): 441-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18841308

RESUMO

An extremely small amount of several heavy metals have been detected in cosmetic products as impurities, which can cause skin allergies through percutaneous adsorption on the skin. We present here a fast, accurate, and highly sensitive method for simultaneous determination of Pb2+, Fe2+, Cu2+, Ni2+, Zn2+, Co2+, Cd2+ and Mn2+ in coloring agents and cosmetic products, to be evaluated by ion chromatography. All of these metals are well separated through a bifunctional ion-exchange column (IonPac CS5A) and detected by post-column reaction and spectrophotometric detection. The calibration graphs are linear (r2 > 0.999), in the range 0.1-1000 microg/ml. Detection limits for a 200-microl sample solution are at the mug/l level, which is sufficient for judging whether the product is safe or not. The relative standard deviations (RSDs) of the retention time and the peak area are less than 0.21% and 1.24%, respectively. The recovery rates are 97-104%. The result shows that the proposed determination method is more sensitive, more accurate, and faster than current methods such as HPLC, ICP-MS and Flame-AAS. The new method was applied to analyze the amount of heavy metals contained in 22 cosmetic products and 11 coloring agents.


Assuntos
Cosméticos/química , Metais Pesados/análise
3.
J Cosmet Sci ; 59(2): 139-50, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18408871

RESUMO

Delivery activity of pH-sensitive 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE):cholesteryl hemisuccinate (CHEMS) liposomes was assessed as an in vitro intracellular carrier system to increase the bioavailability of depigmentation actives. N-glycosylation inhibitors have a glycosylation-inhibiting effect, which is useful for the skin depigmentation that operates by interfering with the maturation of tyrosinase. However, an N-glycosylation inhibitor does not easily pass through skin or even cellular membranes due to its water-soluble property. Therefore, it should be transported to target cells by an efficient delivery carrier to reduce the glycosylated tyrosinase. Glycosylation-inhibiting and depigmentation effects of N-butyldeoxynojirimycine (NB-DNJ) and 1-deoxynojirimycine (DNJ)-loaded liposomes were evaluated using Western blotting and measurement of synthesized melanin. Interestingly, it was found that the pH-sensitive liposomes increased the glycosylation-inhibiting and thus, pigment-lightening effects of N-glycosylation inhibitors in vitro. In addition, cargo materials loaded in pH-sensitive liposomes were found to be much more efficiently delivered into the cytoplasm, as observed in fluorescent-activated cell sorting (FACS) and confocal laser-scanning microscopic (CLSM) analysis. These results indicate that pH-sensitive DOPE:CHEMS liposomes have a strong potential as a carrier system to promote delivery efficiency and to enhance the biological effects of water-soluble actives for applications in cosmetics, personal care products, and pharmaceutics.


Assuntos
Ésteres do Colesterol/administração & dosagem , Glucosamina/análogos & derivados , Lipossomos/administração & dosagem , Melaninas/metabolismo , Fosfatidiletanolaminas/administração & dosagem , Pigmentação/efeitos dos fármacos , 1-Desoxinojirimicina/administração & dosagem , Western Blotting , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Glucosamina/administração & dosagem , Glicosilação/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Melaninas/análise , Melanoma/metabolismo , Microscopia Confocal
4.
Contact Dermatitis ; 58(4): 193-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18353026

RESUMO

BACKGROUND: Worldwide restrictions in animal use for research have driven efforts to develop alternative methods. OBJECTIVE: The study aimed to test the efficacy of the macrophage inflammatory protein-1beta (MIP-1beta) assay for testing chemicals' skin-sensitizing capacity. METHODS: The assay was performed using 9 chemicals judged to be sensitizing and 7 non-sensitizing by the standard in vivo assays. THP-1 cells were cultured in the presence or absence of 4 doses, 0.01x, 0.1x, 0.5x, or 1x IC(50) (50% inhibitory concentration for THP-1 cell proliferation) of these chemicals for 24 hr, and the MIP-1beta level in the supernatants was determined. Skin sensitization by the test chemicals was determined by MIP-1beta production rates. The MIP-1beta production rate was expressed as the relative increase in MIP-1beta production in response to chemical treatment compared with vehicle treatment. RESULTS AND CONCLUSION: When the threshold MIP-1beta production rate used was 100% or 105% of dimethyl sulfoxide, all the sensitizing chemicals tested (dinitrochlorobenzene, hexyl cinnamic aldehyde, eugenol, hydroquinone, dinitrofluorobenzene, benzocaine, nickel, chromium, and 5-chloro-2-methyl-4-isothiazolin-3-one) were positive, and all the non-sensitizing chemicals (methyl salicylate, benzalkonium chloride, lactic acid, isopropanol, and salicylic acid), with the exception of sodium lauryl sulfate, were negative for MIP-1beta production. These results indicate that MIP-1beta could be a biomarker for classification of chemicals as sensitizers or non-sensitizers.


Assuntos
Alérgenos/farmacologia , Alternativas aos Testes com Animais/métodos , Bioensaio/métodos , Quimiocina CCL4/biossíntese , Irritantes/farmacologia , Monócitos/efeitos dos fármacos , Alérgenos/toxicidade , Animais , Biomarcadores/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Cobaias , Humanos , Concentração Inibidora 50 , Irritantes/toxicidade , Monócitos/metabolismo , Pele/efeitos dos fármacos , Estatísticas não Paramétricas , Sais de Tetrazólio , Tiazóis
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 865(1-2): 159-66, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18329967

RESUMO

A new simple, rapid and sensitive high-performance anion-exchange chromatography method with pulsed amperometric detection (HPAEC-PAD) was developed and validated for the simultaneous determination of two Amadori compounds, arginyl-fructose and arginyl-fructosyl-glucose in Korean red ginseng (Panax ginseng) extracts, rat plasma. Separation of the two target analytes was efficiently undertaken on CarboPac PA1 anion-exchange column with isocratic elution (400 mM sodium hydroxide and deionized water (90:10, v/v)) at flow rate 0.7 mL/min within 15 min of single chromatographic run. Under optimized conditions, the detection limits (signal-to-noise ratio equal to 3) were 20 and 25 ng/mL for arginyl-fructose and arginyl-fructosyl-glucose, respectively. Calibration curves of peak area for the two analytes were linear over three orders of magnitude with a correlation coefficients greater than 0.999. The accuracy of the method was tested by recovery measurement of the spiked samples which yielded good results of 94.15-102.62%. This method was successfully applied to the quantification of arginyl-fructose and arginyl-fructosyl-glucose in herbal extracts and in the plasma samples from rat.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Eletroquímica/métodos , Panax/química , Animais , Resinas de Troca Aniônica , Calibragem , Proteínas de Plantas/isolamento & purificação , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
J Microbiol Biotechnol ; 18(1): 110-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18239426

RESUMO

Three kinds of prenylated flavonols, icariside I, icariside II, and icaritin, were isolated from an icariin hydrolysate and their effects on melanogenesis evaluated based on mushroom tyrosinase inhibition and quantifying the melanin contents in melanocytes. Although none of the compounds had an effect on tyrosinase activity, icariside II and icaritin both effectively inhibited the melanin contents with an IC50 of 10.53 and 11.13 MM, respectively. Whereas icariside II was obtained from a reaction with beta-glucosidase and cellulase, the icariin was not completely converted into icariside II. Thus, for the high-purity production of icariside II, the reaction was optimized using the response surface methodology, where an enzyme concentration of 5.0 mg/ml, pH 7, 37.5 degrees C;, and 8 h reaction time were selected as the central conditions for the central composite design (CCD) for the enzymatic hydrolysis of icariin into icariside II using cellulase. Empirical models were developed to describe the relationships between the operating factors and the response (icariside II yield). A statistical analysis indicated that all four factors had a significant effect (p<0.01) on the icariside II production. The coefficient of determination (R2) was good for the model (0.9853), and the optimum production conditions for icariside II was an enzyme concentration of 7.5 mg/ml, pH 5, 50 degrees C, and 12 h reaction time. A good agreement between the predicted and experimental data under the designed optimal conditions confirmed the usefulness of the model. A laboratory pilot scale was also successful.


Assuntos
Epimedium/química , Flavonoides/metabolismo , Melaninas/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Animais , Biotecnologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Flavonas/metabolismo , Flavonas/farmacologia , Flavonoides/farmacologia , Concentração de Íons de Hidrogênio , Hidrólise , Espectrometria de Massas , Melanócitos , Camundongos , Camundongos Endogâmicos C57BL , Umbeliferonas/metabolismo , Umbeliferonas/farmacologia
7.
J Dermatol Sci ; 50(2): 99-107, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18201872

RESUMO

BACKGROUND: Although wrinkling is the most obvious sign of aged skin, the detailed pathomechanism of wrinkle development has not been elucidated. OBJECTIVES: In this study, we investigated the role of elastic fibers in the formation of skin wrinkles. METHODS: Loss of elastic fibers was measured quantitatively in the facial skins of subjects representing seven decades, and then compared with wrinkle severities. We also investigated whether topical retinoic acid treatment to photoaged human skin can restore destroyed elastic fiber, and the correlation between wrinkle improvement with increase in elastic fibers in RA-treated facial skin. RESULTS: We found a significant correlation between decreases in the length, width, number and total area of oxytalan fibers and wrinkle severity. Furthermore, we found that topical application of retinoic acid (0.025%) to chronically photodamaged skin regenerated and restored elastic fibers, and that there was a significant positive correlation between the amount of newly regenerated elastic fiber and the wrinkle improvement caused by retinoic acid. CONCLUSIONS: Our results provide an objective insight into the role of elastic fibers in skin wrinkle formation by providing a quantitative correlation between changes in oxytalan fibers and the severity of skin wrinkling.


Assuntos
Fármacos Dermatológicos/administração & dosagem , Tecido Elástico/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Luz Solar/efeitos adversos , Tretinoína/administração & dosagem , Administração Cutânea , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Tecido Elástico/metabolismo , Tecido Elástico/patologia , Tecido Elástico/efeitos da radiação , Proteínas da Matriz Extracelular/metabolismo , Face , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Pele/metabolismo , Pele/patologia , Pele/efeitos da radiação , Envelhecimento da Pele/patologia , Envelhecimento da Pele/efeitos da radiação , Resultado do Tratamento
8.
J Cosmet Sci ; 59(6): 469-80, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19156330

RESUMO

Methylene bis-benzotriazolyl tetramethyl butylphenol and bis-ethylhexyloxy phenol methoxyphenyl triazine are sunscreen agents that have hydrophobic behaviors in common. They were not normally assayed with the following four sunscreen agents that have hydrophilic behaviors in a single chromatographic run: ethylhexyl methoxycinnamate, isoamyl p-methoxycinnamate, ethylhexyl salicylate, and ethylhexyl triazone. For that reason, methylene bis-benzotriazolyl tetramethyl butylphenol and bis-ethylhexyloxy phenol methoxyphenyl triazine require much time in order to assay products with those materials. A rapid, selective, and reproducible determination method needs to be developed for the simultaneous examination of methylene bis-benzotriazolyl tetramethyl butylphenol and bis-ethylhexyloxy phenol methoxyphenyl triazine with the sunscreen agents, ethylhexyl methoxycinnamate, isoamyl p-methoxycinnamate, ethylhexyl salicylate, and ethylhexyl triazone. This new technique could reduce time in examining the sunscreen agents and be effective for quality control of suncare products. In this paper, the HPLC and UPLC system is used for developing the determination of the sunscreen agents. Several evaluations of some mixtures of eluents and columns were obtained for the optimal condition of separation. In HPLC, the optimal peak resolution was obtained through ethanol-water gradient elution and a 75-mm C18 column with a 3.5-microm-sized particle on a flow rate of 1.0 ml/min. In UPLC, the most distinctive peak resolution was obtained through methanol-water gradient elution and a 50-mm C18 column with a 1.7-microm-sized particle on a flow rate 0.4 ml/min. Both of those chromatographic determination methods could be used in the examination of six types of sunscreen agents without any interference from other product excipients in the agents. The proposed determination methods were validated for specificity, linearity, repeatability, system stability, intermediate precision, and accuracy. Consequently, HPLC and UPLC determination methods could be rapid, selective, and proper applications for the assay of sunscreen agents in suncare products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Protetores Solares/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Cosméticos/química , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Bioorg Med Chem ; 16(2): 732-8, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18029185

RESUMO

The methanol extract from Selaginella tamariscina significantly inhibited UV irradiation induced activity of matrix metalloproteinase-1 (MMP-1) in primary fibroblasts from human skin. Using the technique of bioassay-directed chromatographic separation, five biflavonoids were isolated from the ethyl acetate soluble fraction of S. tamariscina. Here, we investigated the effect of these five biflavonoids on the regulation of MMP-1 and -2 in UV irradiated cultured dermal fibroblasts from human neonatal foreskins. Among these biflavonoids, sumaflavone and amentoflavone showed significant MMP-1 inhibitory activity in primary human dermal fibroblasts after UV irradiation. The IC(50) values of sumaflavone, amentoflavone and retinoic acid, which was used as a positive control, were 0.78, 1.8, and 10microM, respectively.


Assuntos
Biflavonoides/isolamento & purificação , Biflavonoides/farmacologia , Selaginellaceae/química , Envelhecimento/efeitos dos fármacos , Envelhecimento/efeitos da radiação , Biflavonoides/química , Fibroblastos/efeitos da radiação , Humanos , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 1 da Matriz/efeitos da radiação , Estrutura Molecular , Pele/citologia , Pele/efeitos da radiação
10.
J Nanosci Nanotechnol ; 7(11): 3944-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18047093

RESUMO

Micelle-to-vesicle transition method was used to make liposomes containing oleanolic acid. First, the solubilization of potassium salt of oleanolic acid at basic condition by micelle formation was confirmed. Using the soluble state of oleanolic acid at basic condition, liposomes containing oleanolic acid was prepared by adjusting pH. After making homogeneous aqueous mixture of potassium salt of oleanolic acid and lecithin in basic condition, the solution was neutralized to produce the lecithin-based liposomes that contain oleanolic acid inside the lipid bilayers. The optimal loading of oleanolic acid to lecithin (about 25 mole%) was found to exist to produce liposomal suspension of small size without homogenization step. Electron microscopy and dynamic light scattering studies showed that the narrowly distributed, reconstituted oleanolic acid-containing liposomes were prepared without severe mechanical treatment.


Assuntos
Coloides/química , Cristalização/métodos , Lipossomos/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Ácido Oleanólico/química , Substâncias Macromoleculares/química , Teste de Materiais , Micelas , Conformação Molecular , Tamanho da Partícula , Transição de Fase , Solubilidade , Propriedades de Superfície
11.
Biochem Pharmacol ; 74(5): 780-6, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17658483

RESUMO

It is well known that c-kit is related to pigmentation as well as to the oncology target protein. The objective of this study was to discover a skin-whitening agent that regulates c-kit activity. We have developed a high-throughput screening system using recombinant human c-kit protein. Approximately 10,000 synthetic compounds were screened for their effect on c-kit activity. Phenyl-imidazole sulfonamide derivatives showed inhibitory activity on c-kit phosphorylation in vitro. The effects of one derivative, [4-t-butylphenyl]-N-(4-imidazol-1-yl phenyl)sulfonamide (ISCK03), on stem-cell factor (SCF)/c-kit cellular signaling in 501mel human melanoma cells were examined further. Pretreatment of 501mel cells with ISCK03 inhibited SCF-induced c-kit phosphorylation dose dependently. ISCK03 also inhibited p44/42 ERK mitogen-activated protein kinase (MAPK) phosphorylation, which is known to be involved in SCF/c-kit downstream signaling. However ISCK03 did not inhibit hepatocyte growth factor (HGF)-induced phosphorylation of p44/42 ERK proteins. To determine the in vivo potency of ISCK03, it was orally administered to depilated C57BL/6 mice. Interestingly, oral administration of ISCK03 induced the dose-dependent depigmentation of newly regrown hair, and this was reversed with cessation of ISCK03 treatment. Finally, to investigate whether the inhibitory effect of ISCK03 on SCF/c-kit signaling abolished UV-induced pigmentation, ISCK03 was applied to UV-induced pigmented spots on brownish guinea pig skin. The topical application of ISCK03 promoted the depigmentation of UV-induced hyperpigmented spots. Fontana-Masson staining analysis showed epidermal melanin was diminished in spots treated with ISCK03. These results indicate that phenyl-imidazole sulfonamide derivatives are potent c-kit inhibitors and might be used as skin-whitening agents.


Assuntos
Imidazóis/farmacologia , Melaninas/biossíntese , Melanoma/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica , Cobaias , Humanos , Hiperpigmentação/tratamento farmacológico , Imidazóis/química , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Fosforilação , Sulfonamidas/química
12.
J Colloid Interface Sci ; 311(1): 243-52, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17382337

RESUMO

In the current study, we examined the effect of polymer characteristics on the structure of complexes formed between poly(methacrylic acid-co-n-alkyl methacrylate) and with phosphatidylcholine/cholesterol liposomes. We varied the polymer concentration in the vesicles, the preparation concentration of lipid and polymer components during preparation, the molecular weight of the polymer chain, the molecular weight of the polymer's hydrophobic side groups and their mole fraction. The vesicle behavior indicated polymer-free bilayers and bilayers complexed with polymer coexisted at low polymer concentrations. As the polymer concentration exceeds a critical level, however, the system became homogeneous, indicating bilayer uniformity of the bilayer. As the polymer content was raised, the vesicle size and fluidity increased, and the transition temperature decreased. We found that the vesicle size mostly affects the membrane fluidity. We also found that the thermal properties (transition temperature and the magnitude of heat capacity of the peak, DeltaCp) are governed by the effects of the polymer on the structure of bilayer. The length of the alkyl chain of the polymer is shown to significantly affect the structure of polymer-liposome complexes, as did the chain molecular weight and mole concentration of hydrophobic group in the polymer.


Assuntos
Lipossomos/química , Metacrilatos/química , Polímeros/química , Colesterol/química , Metacrilatos/síntese química , Tamanho da Partícula , Fosfatidilcolinas/química , Polímeros/síntese química , Propriedades de Superfície , Temperatura
13.
J Biol Chem ; 282(4): 2456-65, 2007 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-17118936

RESUMO

Prp19p is an integral component of the heteromeric protein complex (the NineTeen complex) in the nucleus, and it is essential for the structural integrity of NineTeen complex and its subsequent activation of the spliceosome. We identified Prp19p, which has never been reported in relation to any function outside of the nucleus, as a member of proteins associated with lipid droplets. Down-regulation of Prp19p expression with RNA interference in 3T3-L1 cells repressed lipid droplet formation with the reduction in the level of expression of perilipin and S3-12. The levels of expression of SCD1 (stearoyl-CoA desaturase-1), DGAT-1 (acyl-CoA diacylglycerol acyltransferase-1), and glycerol-3-phosphate acyltransferase were also reduced in Prp19p down-regulated cells, and a significant decrease in triglycerides was observed. Unlike perilipin, which is one of the most extensively studied lipid droplet-associated proteins, Prp19p is not essential for cAMP- and hormone-sensitive lipase-dependent lipolysis pathways, even though Prp19p is a component of the lipid droplet phospholipid monolayer, and down-regulation of Prp19p represses fat accretion significantly. These results suggest that Prp19p or Prp19-interacting proteins during lipid droplet biogenesis in adipocytes may be considered as another class of potential targets for attacking obesity and obesity-related problems.


Assuntos
Corpos de Inclusão/metabolismo , Metabolismo dos Lipídeos , Proteínas Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae , Células 3T3-L1 , Adipócitos/metabolismo , Adipócitos/ultraestrutura , Animais , Proteínas de Transporte , Diacilglicerol O-Aciltransferase/metabolismo , Regulação para Baixo , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Lipólise , Masculino , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas à Matriz Nuclear , Perilipina-1 , Perilipina-4 , Fosfoproteínas/antagonistas & inibidores , Interferência de RNA , Fatores de Processamento de RNA , Spliceossomos , Estearoil-CoA Dessaturase/metabolismo
14.
Talanta ; 71(5): 2129-33, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19071575

RESUMO

This study describes a flexible approach that allows us to characterize the long-term stability of antioxidants by using a thermodynamically extended Arrhenius equation. We use retinol, Vitamin A, as a model antioxidant and its degradation behaviors are characterized for both stabilized and non-stabilized systems; in this study, by using a fluid bed technique, we immobilize the retinol in lipid particles, thus increasing its thermal stability in complex formulations, such as aqueous polymer gels and emulsions. Our approach demonstrates that the degradation behaviors of the retinol show a functional relationship with temperature and time, which makes it possible to use the Arrhenius approach. This result allows us to precisely characterize the stability of antioxidants in complex formulations for long time.

15.
J Cosmet Sci ; 57(5): 377-83, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17111072

RESUMO

Nowadays there are many sun-protection cosmetics incorporating organic or inorganic UV filters as active ingredients. Chemically stable inorganic sunscreen agents, usually metal oxides, are widely employed in high-SPF (sun protection factor) products. Titanium dioxide is one of the most frequently used inorganic UV filters. It has been used as a pigment for a long period of cosmetic history. With the development of micronization techniques, it has become possible to incorporate titanium dioxide in sunscreen formulations without the previous whitening effect, and hence its use in cosmetics has become an important research topic. However, there are very few works related to quantitation of titanium dioxide in sunscreen products. In this research, we analyzed the amounts of titanium dioxide in sunscreen cosmetics by adapting redox titration, reduction of Ti(IV) to Ti(III), and reoxidation to Ti(IV). After calcification of other organic ingredients of cosmetics, titanium dioxide is dissolved by hot sulfuric acid. The dissolved Ti(IV) is reduced to Ti(III) by adding metallic aluminum. The reduced Ti(III) is titrated against a standard oxidizing agent, Fe(III) (ammonium iron(III) sulfate), with potassium thiocyanate as an indicator. In order to test the accuracy and applicability of the proposed method, we analyzed the amounts of titanium dioxide in four types of sunscreen cosmetics, namely cream, make-up base, foundation, and powder, after adding known amounts of titanium dioxide (1 approximately 25 w/w%). The percentages of titanium dioxide recovered in the four types of formulations were in the range between 96% and 105%. We also analyzed seven commercial cosmetic products labeled with titanium dioxide as an ingredient and compared the results with those obtained from ICP-AES (inductively coupled plasma-atomic emission spectrometry), one of the most powerful atomic analysis techniques. The results showed that the titrated amounts were well in accord with the analyzed amounts of titanium dioxide by ICP-AES. Although instrument-based analytical methods, namely ICP-MS (inductively coupled plasma-mass spectrometry) and ICP-AES, are best for the analysis of titanium, it is difficult for small cosmetic companies to install such instruments because of their high cost. It was found that the volumetric method presented here gives quantitatively accurate and reliable results with routine lab-ware and chemicals.


Assuntos
Cosméticos/química , Análise Espectral/métodos , Titânio/análise
16.
Arch Dermatol Res ; 298(6): 273-82, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16977445

RESUMO

Peroxisome proliferators activated receptors (PPARs) are a family of nuclear hormone receptors that heterodimer with the retinoid X receptor and function as transcriptional regulators of genes. Topically Applied PPAR-alpha agonists possess receptor mediated, pro-differentiating/anti-proliferative effects, lipid metabolism stimulation, and anti-inflammatory activity, which suggest that they could be beneficial for the treatment of a variety of cutaneous diseases. Hyaluronan (HA), a high-molecular-weight linear glycosaminoglycan consisting of alternating D: -glucuronic acid and N-acetyl-D: -glucosamine residues, is one of the major extracellular matrix components in skin. Among the family of HA synthase genes (HAS1, 2, 3) so far identified, one group has demonstrated that the expressions of HAS2 and HAS3 play crucial roles in the regulation of HA synthesis in human skin fibroblasts and keratinocytes, respectively, but the precise regulatory mechanisms are still unknown. We examine Musk T called Ethylene brassylate, Astratone or 1,4-Dioxacycloheptadecane-5,17-dione, which used as just a perfume ingredient, plays a role as PPAR-alpha ligand in vitro and stimulates skin barrier recovery, ceramide synthesis, beta-Glucocerebrosidase, involucrin expression in epidermis in vivo; and examine that Musk T stimulates HAS expression and HA synthesis in human skin fibroblast. Through these experiments, we conclude that Musk T is PPAR-alpha ligand, effects on keratinocyte differentiation, intercellular lipid synthesis in epidermis, HA synthesis stimulation in dermis.


Assuntos
Epiderme/metabolismo , Éteres Cíclicos/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Homeostase/fisiologia , Ácido Hialurônico/metabolismo , PPAR alfa/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Chlorocebus aethiops , Epiderme/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Proteínas Filagrinas , Glucuronosiltransferase/metabolismo , Homeostase/efeitos dos fármacos , Humanos , Hialuronan Sintases , Proteínas de Filamentos Intermediários/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , Camundongos Pelados , Precursores de Proteínas/metabolismo , RNA Mensageiro/metabolismo
18.
Contact Dermatitis ; 54(5): 244-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16689807

RESUMO

Chromium hydroxide green [Cr(2)O(OH)(4)] and chromium oxide green (Cr(2)O(3)) are colouring agents for use in cosmetic products. These colourants may contain chromium (VI), which cause skin allergies through percutaneous adsorption on the skin. Eye shadow is a representative cosmetic product in which significant colourants are used. We analysed the chromium (VI) in the eye shadows by ion chromatography and post column derivatization. We optimize conditions of chromium (VI) analysis in eye shadows. During the pretreatment procedure, there are no exchange of chromium (III) to chromium (VI). This method has a limit of quantification for chromium (VI) of 1.0 microg l(-1), recovery rate of 100 +/- 3% and analysis time less than 10 min. This result is 300 times more sensitive than the high-performance liquid chromatography method. We applied the optimized method to analyse 22 eye shadows and 6 colouring agents. 2 out of 22 of the products contained more than 5 mg l(-1). In our previous work, 5 mg l(-1) of Cr represented a threshold level. There was much more Cr(VI) in the colouring agents. The Cr(VI) in one of the colouring agents was 97.6 mg l(-1).


Assuntos
Alérgenos/efeitos adversos , Cromo/efeitos adversos , Cosméticos/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Alérgenos/química , Cromatografia Líquida de Alta Pressão , Cromo/química , Cosméticos/química , Humanos , Reprodutibilidade dos Testes
19.
J Agric Food Chem ; 54(8): 2951-6, 2006 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-16608214

RESUMO

Among the flavonols in green tea, kaempferol has many biological activities but kaempferol of plant origin is too expensive to be used in commercial products. Recently, we confirmed that green tea seed (GTS) contained a reasonable amount of kaempferol glycoside. After conducting structure analysis, two kaempferol glycosides were identified, kaempferol-3-O-[2-O-beta-D-galactopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 1) and kaempferol-3-O-[2-O-beta-D-xylopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 2), respectively. Also, a commercially useful method for kaempferol preparation was suggested by enzymatic hydrolysis using these two flavonoids. After several enzyme reactions were performed for the complete bioconversion of compounds 1 and 2 to kaempferol, we found that the optimum enzyme combination was reaction with beta-galactosidase and hesperidinase. Finally, we produced pure kaempferol with over 95% purity. We also compared the antioxidant effect of these two GTS flavonoids and its aglycone, kaempferol. Kaempferol is a more efficient scavenger of 1,1-diphenyl-2-picrylhydrazyl radicals and a better inhibitor of xanthine/xanthine oxidase than the two glycosides.


Assuntos
Antioxidantes/farmacologia , Camellia sinensis/química , Quempferóis/isolamento & purificação , Quempferóis/farmacologia , Sementes/química , Inibidores Enzimáticos/farmacologia , Sequestradores de Radicais Livres , Glicosídeo Hidrolases/metabolismo , Hidrólise , Xantina Oxidase/antagonistas & inibidores , beta-Galactosidase/metabolismo
20.
Biosci Biotechnol Biochem ; 70(2): 387-94, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16495654

RESUMO

Two kaempferol glycosides were isolated from green tea seed extract (GTSE). After conducting a structure analysis, these two compounds were identified as kaempferol-3-O-[2-O-beta-D-galactopyranosyl-6-O-alpha-L-rhamnopyranosyl]-beta-D-glucopyranoside (compound 1) and kaempferol-3-O-[2-O-beta-D-xylopyranosyl-6-O-alpha-L-rhanmopyranosyl]-beta-D-glucopyranoside (compound 2). These two compounds were hydrolysed by o-glycolytic enzymes for the production of kaempferol. After performing several reactions, we found the optimum enzyme combination, a reaction with beta-galactosidase and hesperidinase. Finally, we produced kaempferol of above 95% purity. The 5alpha-reductase inhibition activities of GTSE hydrolysate (GTSE-H) containing kaempferol were evaluated by the contact cell-based metabolic method using a stable HEK 293 cell line. GTSE-H showed a good inhibition effect on HEK 293 cell lines both type 1 and type 2 on 5alpha-reductase. Especially, GTSE-H inhibited type 2 with kaempferol content dependency. The results indicate that the inhibition activity of hydrolysate on 5alpha-reductase type 2 increases in accordance with kaempferol content.


Assuntos
Inibidores Enzimáticos/farmacologia , Oxirredutases/antagonistas & inibidores , Sementes/química , Chá/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Cor , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glicosilação/efeitos dos fármacos , Humanos , Hidrólise , Estrutura Molecular , Oxirredutases/genética , Oxirredutases/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia
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