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1.
Biofactors ; 41(6): 383-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26648450

RESUMO

Ubiquinone (coenzyme Q10, Q10) represents an endogenously synthesized lipid-soluble antioxidant which is crucial for cellular energy production but is diminished with age and under the influence of external stress factors in human skin. Here, it is shown that topical Q10 treatment is beneficial with regard to effective Q10 replenishment, augmentation of cellular energy metabolism, and antioxidant effects. Application of Q10-containing formulas significantly increased the levels of this quinone on the skin surface. In the deeper layers of the epidermis the ubiquinone level was significantly augmented indicating effective supplementation. Concurrent elevation of ubiquinol levels suggested metabolic transformation of ubiquinone resulting from increased energy metabolism. Incubation of cultured human keratinocytes with Q10 concentrations equivalent to treated skin showed a significant augmentation of energy metabolism. Moreover, the results demonstrated that stressed skin benefits from the topical Q10 treatment by reduction of free radicals and an increase in antioxidant capacity.


Assuntos
Antioxidantes/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Pele/efeitos dos fármacos , Ubiquinona/análogos & derivados , Administração Tópica , Antioxidantes/metabolismo , Linhagem Celular , Suplementos Nutricionais , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Pele/metabolismo , Pele/patologia , Ubiquinona/administração & dosagem , Ubiquinona/metabolismo
2.
J Invest Dermatol ; 134(7): 1862-1872, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24670384

RESUMO

Changes in the mechanical properties of dermis occur during skin aging or tissue remodeling and affect the activity of resident fibroblasts. With the aim to establish elastic culture substrates that reproduce the variable softness of dermis, we determined Young's elastic modulus E of human dermis at the cell perception level using atomic force microscopy. The E of dermis ranged from 0.1 to 10 kPa, varied depending on body area and dermal layer, and tended to increase with age in 26-55-year-old donors. The activation state of human dermal fibroblasts cultured on "skin-soft" E (5 kPa) silicone culture substrates was compared with stiff plastic culture (GPa), collagen gel cultures (0.1-9 kPa), and fresh human dermal tissue. Fibroblasts cultured on skin-soft silicones displayed low mRNA levels of fibrosis-associated genes and increased expression of the matrix metalloproteinases (MMPs) MMP-1 and MMP-3 as compared with collagen gel and plastic cultures. The activation profile exhibited by fibroblasts on "skin-soft" silicone culture substrates was most comparable with that of human dermis than any other tested culture condition. Hence, providing biomimetic mechanical conditions generates fibroblasts that are more suitable to investigate physiologically relevant cell processes than fibroblasts spontaneously activated by stiff conventional culture surfaces.


Assuntos
Derme/fisiologia , Matriz Extracelular/fisiologia , Matriz Extracelular/ultraestrutura , Fibroblastos/fisiologia , Fibroblastos/ultraestrutura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Fenômenos Biomecânicos/fisiologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Derme/citologia , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Masculino , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Microscopia de Força Atômica , Pessoa de Meia-Idade , Transcriptoma , Adulto Jovem
3.
J Dermatol Sci ; 69(2): 132-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23148930

RESUMO

BACKGROUND: Skin derived precursors (SKP) comprise a subset of specialized dermal cells that can be distinguished from fibroblast by their capacity for spheroidal growth. Recent investigations have shown that hair follicles constitute a niche for this cell type, but their localization and their definite function in non-follicular skin remains largely unknown. OBJECTIVE: To identify the dermal niche of non-follicular SKPs and to analyze whether functional aspects correlate with this localization. METHODS: SKPs were isolated from separate anatomical regions of human abdominal skin. Fluorescence activated cell sorting then was used to obtain a pure population of non-follicular SKPs. Functional characterization of these cells was performed applying differentiation and proliferation assays. Information on specific in vivo functions was derived from histological evaluation of quantity and localization patterns. RESULTS: Sphere forming capacity and differentiation assays show that SKPs reside in the papillary part of the dermis. Further delineation revealed that the dermal capillaries represent a niche for these cells which subsequently could be isolated by FACS utilizing a perivascular marker. Whereas functional properties described for follicular SKPs could also be detected in the perivascular SKP population, histological analyses additionally point to a cross-talk with epidermal stem cells and a reduction during chronological aging. CONCLUSION: Our data show that SKPs isolated from non-follicular skin originate from a perivascular niche. Compared to their follicular counterparts, no functional differences could be observed upon cultivation, but ex vivo analyses also point to unique functions and a contribution to the phenotype of aged skin.


Assuntos
Células-Tronco Adultas/citologia , Derme/citologia , Fibroblastos/citologia , Folículo Piloso/citologia , Pericitos/citologia , Nicho de Células-Tronco/fisiologia , Abdome , Adipogenia/fisiologia , Adulto , Antígeno CD146/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Citometria de Fluxo , Humanos , Osteogênese/fisiologia , Pericitos/metabolismo , Envelhecimento da Pele/fisiologia
4.
J Cosmet Dermatol ; 10(4): 273-81, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22151935

RESUMO

BACKGROUND: The dermal extracellular matrix provides stability and structure to the skin. With increasing age, however, its major component collagen is subject to degeneration, resulting in a gradual decline in skin elasticity and progression of wrinkle formation. Previous studies suggest that the reduction in cellular energy contributes to the diminished synthesis of cutaneous collagen during aging. AIMS: To investigate the potential of topically applied creatine to improve the clinical signs of skin aging by stimulating dermal collagen synthesis in vitro and in vivo. PATIENTS/METHODS: Penetration experiments were performed with a pig skin ex vivo model. Effects of creatine on dermal collagen gene expression and procollagen synthesis were studied in vitro using cultured fibroblast-populated collagen gels. In a single-center, controlled study, 43 male Caucasians applied a face-care formulation containing creatine, guarana extract, and glycerol to determine its influence on facial topometric features. RESULTS: Cultured human dermal fibroblasts supplemented with creatine displayed a stimulation of collagen synthesis relative to untreated control cells both on the gene expression and at the protein level. In skin penetration experiments, topically applied creatine rapidly reached the dermis. In addition, topical in vivo application of a creatine-containing formulation for 6 weeks significantly reduced the sagging cheek intensity in the jowl area as compared to baseline. This result was confirmed by clinical live scoring, which also demonstrated a significant reduction in crow's feet wrinkles and wrinkles under the eyes. CONCLUSIONS: In summary, creatine represents a beneficial active ingredient for topical use in the prevention and treatment of human skin aging.


Assuntos
Colágeno/biossíntese , Creatina/farmacocinética , Creatina/uso terapêutico , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Adulto , Idoso , Animais , Células Cultivadas , Colágeno/genética , Creatina/farmacologia , Elasticidade/efeitos dos fármacos , Fibroblastos/metabolismo , Expressão Gênica , Glicerol/farmacologia , Glicerol/uso terapêutico , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Paullinia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Pró-Colágeno/biossíntese , Absorção Cutânea , Estatísticas não Paramétricas , Suínos
5.
J Cosmet Dermatol ; 10(1): 15-23, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21332911

RESUMO

BACKGROUND: The decrease in firmness is a hallmark of skin aging. Accelerated by chronic sun exposure, fundamental changes occur within the dermal extracellular matrix over the years, mainly impairing the collagenous network. AIMS: Based on the qualitative and quantitative assessment of skin firmness, in vitro and in vivo studies were carried out to elucidate the effects of topical folic acid and creatine to counteract this age-dependent reduction in the amount of collagen. PATIENTS/METHODS: Topical application of a commercially available formulation containing folic acid and creatine was performed to study effects on skin firmness in vivo using cutometric analysis. Imaging and quantification of collagen density were carried out using multiphoton laser scanning microscopy (MPLSM). To investigate the effects of these compounds on collagen gene expression, procollagen synthesis, and collagen fibril organization, complementary in vitro studies on cultured fibroblast-populated collagen gels were carried out. RESULTS: The underlying structural changes in the collagen network of young and aged sun-exposed facial skin in vivo were visualized by MPLSM. Topical application of a folic acid- and creatine-containing formulation significantly improved firmness of mature skin in vivo. Treatment of fibroblast-populated dermal equivalents with folic acid and creatine increased collagen gene expression and procollagen levels and improved collagen fiber density, suggesting that the in vivo effects are based on the overall improvement of the collagen metabolism. CONCLUSIONS: Employing MPLSM, dermal changes occurring in photo-aged human skin were visualized in an unprecedented manner and correlated to a loss of firmness. Treatment of aged skin with a topical formulation containing folic acid and creatine counteracted this age-dependent decline by exerting sustained effects on collagen metabolism. Our results support previous findings on the efficacy of these actives.


Assuntos
Colágeno/efeitos dos fármacos , Creatinina/farmacologia , Ácido Fólico/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Complexo Vitamínico B/farmacologia , Administração Tópica , Adulto , Idoso , Células Cultivadas , Colágeno/genética , Colágeno/metabolismo , Elasticidade/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Microscopia/métodos , Pessoa de Meia-Idade , Pró-Colágeno/metabolismo , RNA Mensageiro/metabolismo , Pele/ultraestrutura , Luz Solar/efeitos adversos , Adulto Jovem
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