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1.
Biol Pharm Bull ; 47(1): 240-244, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38246611

RESUMO

Studies showing that Panax ginseng promotes hair growth have largely been conducted using mice; there are few reports on how P. ginseng affects human hair growth. In particular, little is known about its effect on the telogen to anagen transition. To determine the effect of P. ginseng on human hair growth and the transition from the telogen to the anagen phase. The effects of P. ginseng extract (PGE) and the three major ginsenoside components, Rb1, Rg1, and Re, on the proliferation of human dermal papilla cells (DPCs) and human outer root sheath cells (ORSCs) were investigated. The effects of these compounds on the cell expression of bone morphogenetic protein 4 (BMP4), fibroblast growth factor 18 (FGF18) and Noggin were assessed by real-time PCR. The effect of PGE on hair-shaft elongation was determined in a human hair follicle organ-culture system. PGE and the three ginsenosides stimulated the proliferation of DPCs and ORSCs and suppressed BMP4 expression in DPCs but did not affect FGF18 expression in ORSCs and Noggin expression in DPCs. PGE stimulated hair-shaft growth. PGE and the ginsenosides Rb1, Rg1, and Re stimulate the transition from the telogen phase to anagen phase of the hair cycle by suppressing BMP4 expression in DPCs. These compounds might be useful for promoting the growth of human hair.


Assuntos
Ginsenosídeos , Panax , Humanos , Animais , Camundongos , Ginsenosídeos/farmacologia , Proteína Morfogenética Óssea 4 , Proliferação de Células , Cabelo , Extratos Vegetais/farmacologia
2.
J Anat ; 242(6): 1012-1028, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36774410

RESUMO

Lanceolate nerve endings (LNEs) surrounding hair follicles (HFs) play an important role in detecting hair deflection. Complexes of the LNEs form a palisade-like structure along the longitudinal axis of hair roots in which axons are sandwiched between two processes of terminal Schwann cells (tSCs) at the isthmus of HFs. The structure and molecular mechanism of LNEs in animal sinus hair, pelage, and human vellus hairs have been investigated. Despite the high density of HFs in human scalp skin, the LNEs in human terminal HFs have not been investigated. In this study, we aimed to reveal the distribution and ultrastructure of LNEs in terminal HFs of human scalp skin. Using light-sheet microscopy and immunostaining, the LNEs were observed at one terminal HF but not at the other terminal HFs in the same follicular unit. The ultrastructure of the LNEs of terminal HFs in human scalp skin was characterized using correlated light and electron microscopy (CLEM). Confocal laser microscopy and transmission electron microscopy of serial transverse sections of HFs revealed that LNEs were aligned adjacent to the basal lamina outside the outer root sheath (ORS), at the isthmus of terminal HFs, and adjacent to CD200-positive ORS cells in the upper bulge region. Moreover, axons with abundant mitochondria were sandwiched between tSCs. Three-dimensional CLEM, specifically confocal laser microscopy and focused ion beam scanning electron microscopy, of stained serial transverse sections revealed that LNEs were wrapped with type I and type II tSCs, with the processes protruding from the space between the Schwann cells. Moreover, the ultrastructures of LNEs at miniaturized HFs were similar to those of LNEs at terminal HFs. Preembedding immunoelectron microscopy revealed that Piezo-type mechanosensitive ion channel component 2 (Piezo2), a gated ion channel, was in axons and tSCs and adjacent to the cell membrane of axons and tSCs, suggesting that LNEs function as mechanosensors. The number of LNEs increased as the diameter of the ORS decreased, suggesting that LNEs dynamically adapt to the HF environment as terminal HFs miniaturize into vellus-like hair. These findings will provide insights for investigations of mechanosensory organs, aging, and re-innervation during wound healing.


Assuntos
Folículo Piloso , Couro Cabeludo , Animais , Humanos , Folículo Piloso/inervação , Folículo Piloso/ultraestrutura , Microscopia Eletrônica de Volume , Cabelo , Terminações Nervosas/ultraestrutura , Microscopia Eletrônica de Varredura
3.
Exp Dermatol ; 32(5): 671-677, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36514876

RESUMO

The pathological mechanism responsible for EGFR inhibitor (EGFRI)-induced skin rash remains unclear. Recent studies reveal associations between skin dysbiosis and skin inflammatory diseases. This study aimed to examine whether skin dysbiosis is associated with EGFRI-induced skin rash. Bacterial swabs were taken from the forehead of 17 cancer patients at baseline and at several time points after EGFRIs initiation, as well as from 20 healthy controls. The skin microbiome was analysed using 16S rRNA sequencing. The severity of the skin rash was assessed using the rash grade. Skin surface parameters (pH, water capacitance, and sebum level) were also measured. Compared with baseline, the abundance of Cutibacterium acnes decreased in 13 of 15 cases, and that of Staphylococcus aureus, Corynebacterium spp., Staphylococcus epidermidis or Proteobacteria increased in 13 of 15 cases after EGFRIs initiation. Skin pH increased significantly in parallel with a decrease in water capacitance after EGFRI initiation. Also, the composition of the skin microbiome of patients with severe rash was significantly different from that of healthy controls. In addition, the skin dysbiosis did not return to baseline during EGFRIs treatment for >1 year. These longitudinal observations indicate that skin dysbiosis is associated with development of skin rash.


Assuntos
Exantema , Microbiota , Dermatopatias , Humanos , Disbiose , RNA Ribossômico 16S , Pele/patologia , Microbiota/genética , Receptores ErbB , Água
4.
Cancer Sci ; 113(12): 4230-4243, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36082621

RESUMO

Breast cancer gene 1 (BRCA1) plays roles in DNA repair and centrosome regulation and is involved in DNA damage-induced centrosome amplification (DDICA). Here, the centrosomal localization of BRCA1 and the kinases involved in centrosome duplication were analyzed in each cell cycle phase after treatment with DNA crosslinker cisplatin (CDDP). CDDP treatment increased the centrosomal localization of BRCA1 in early S-G2 phase. BRCA1 contributed to the increased centrosomal localization of Aurora A in S phase and that of phosphorylated Polo-like kinase 1 (PLK1) in late S phase after CDDP treatment, resulting in centriole disengagement and overduplication. The increased centrosomal localization of BRCA1 and Aurora A induced by CDDP treatment involved the nuclear export of BRCA1 and BRCA1 phosphorylation by ataxia telangiectasia mutated (ATM). Patient-derived variants and mutations at phosphorylated residues of BRCA1 suppressed the interaction between BRCA1 and Aurora A, as well as the CDDP-induced increase in the centrosomal localization of BRCA1 and Aurora A. These results suggest that CDDP induces the phosphorylation of BRCA1 by ATM in the nucleus and its transport to the cytoplasm, thereby promoting the centrosomal localization Aurora A, which phosphorylates PLK1. The function of BRCA1 in the translocation of the DNA damage signal from the nucleus to the centrosome to induce centrosome amplification after CDDP treatment might support its role as a tumor suppressor.


Assuntos
Aurora Quinase A , Proteína BRCA1 , Centrossomo , Dano ao DNA , Humanos , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Centrossomo/metabolismo , Fase G2 , Fosforilação , Aurora Quinase A/metabolismo
6.
Can J Microbiol ; 68(5): 315-328, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35044838

RESUMO

Six phenanthrene-degrading bacteria were isolated from surface seawater sampled from the western Pacific Ocean. They were identified as Sphingobium xenophagum (formerly Sphingomonas xenophaga) based on morphological, biochemical, and chemical characteristics, and 16S rRNA sequences. The salinity ranges for the growth of these isolates were broader than those of the seven reported Sphingomonas strains isolated from soil, and the optimum NaCl concentration in the growth medium was higher than that for soil sphingomonads. These isolates also exhibited higher phenanthrene-degrading activity under briny conditions than that of a phenanthrene-degrading Sphingomonas strain isolated from soil. A DNA fragment carrying nah genes, which are encoded on the naphthalene-catabolic plasmid NAH of Pseudomonas putida PpG7, hybridised less strongly with the total DNA of all isolates. Certain genes involved in phenanthrene degradation were also preliminarily characterised in all isolates. This is the first demonstration that S. xenophagum strains, which are able to degrade phenanthrene, are widely distributed in marine environments, and that the growth and phenanthrene-degrading activity of these strains are adapted to briny conditions. The results also suggest that genes for phenanthrene degradation, which are dissimilar to nah genes, were also ubiquitously distributed in marine strains.


Assuntos
Fenantrenos , Sphingomonadaceae , Sphingomonas , Biodegradação Ambiental , Oceano Pacífico , Fenantrenos/metabolismo , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo , Sphingomonadaceae/genética , Sphingomonadaceae/metabolismo , Sphingomonas/genética , Sphingomonas/metabolismo
7.
Int J Cosmet Sci ; 43(6): 764-771, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34664283

RESUMO

OBJECTIVE: The purpose of this study was to clarify the impact of protein carbonylation on the chemical characteristics of the hair surface focusing on hydrophobicity. METHODS: First, we examined the validity of methods to evaluate hydrophobicity, one that utilizes the fluorescence of 1-anilinonaphtalene-8-sulfonic acid (1,8-ANS) compared with the contact angles against H2 O, of the hair surface chemically modified by alkaline hydrolysis or treated with stearyl ammonium chloride. We measured hairs bleached with H2 O2 or treated with acrolein for fluorescence originating from 1,8-ANS, for the contact angle and for changes of functional groups, aldehydes (the degree of carbonylation), NH2 , COOH and SH, using fluorescence labelling methods. RESULTS: The fluorescence intensity of 1,8-ANS of the hair surface modified chemically correlated well with the contact angles against H2 O. The results indicated that 1,8-ANS is suitable for evaluating the hydrophobicity of the hair surface. The hydrophobicity of hairs bleached with H2 O2 or carbonylated with acrolein was decreased. In addition, changes of functional groups in hairs carbonylated with acrolein increased as did those of hairs bleached with H2 O2 . CONCLUSION: The results suggest that the carbonylation of proteins at the hair surface with aldehydes decreases hydrophobicity and promotes further damage as does bleaching.


OBJECTIF: l'objectif de cette étude était de clarifier l'impact de la carbonylation des protéines sur les caractéristiques chimiques de la surface des cheveux en se concentrant sur l'hydrophobicité. MÉTHODES: nous avons d'abord examiné la validité de la méthode d'évaluation de l'hydrophobicité, une méthode qui utilise la fluorescence de l'acide 1-anilinonaphtalène-8-sulfonique (1,8-ANS) par rapport aux angles de contact avec l'H2O, de la surface des cheveux chimiquement modifiés par hydrolyse alcaline ou traités par chlorure d'ammonium stéarylique. Nous avons mesuré la fluorescence provenant du 1,8-ANS, l'angle de contact et les modifications des groupes fonctionnels, aldéhydes (le degré de carbonylation), NH2, COOH et SH des cheveux décolorés à l'H2O2 ou traités par acroléine, à l'aide de méthodes de marquage par fluorescence. RÉSULTATS: l'intensité de la fluorescence du 1,8-ANS de la surface des cheveux modifiés chimiquement était bien corrélée aux angles de contact avec l'H2O. Les résultats ont indiqué que le 1,8-ANS était adapté à l'évaluation de l'hydrophobicité de la surface des cheveux. L'hydrophobicité des cheveux décolorés à l'H2O2 ou carbonylés à l'acroléine a diminué. De plus, les modifications des groupes fonctionnels des cheveux carbonylés par l'acroléine ont augmenté, tout comme celles des cheveux décolorés à l'H2O2. CONCLUSION: les résultats suggèrent que la carbonylation des protéines à la surface des cheveux par des aldéhydes diminue l'hydrophobicité et favorise d'autres dommages, tout comme la décoloration.


Assuntos
Cabelo/química , Interações Hidrofóbicas e Hidrofílicas , Carbonilação Proteica , Aldeídos/química , Humanos , Peróxido de Hidrogênio/química
8.
J Oleo Sci ; 70(5): 721-730, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33840665

RESUMO

The performance of sunscreen products depends on their ultraviolet (UV) absorption ability through the film formed on the skin surface upon their application. Therefore, it is important that a uniform film is formed on the uneven skin surface for effective sunscreen performance. Because most UV filters are oil soluble, we hypothesized in this study that increasing the viscosity of the oil phase of a sunscreen product can improve the performance of the sunscreen. We first examined the association between the concentration of the oil thickener and the UV absorption ability of the sunscreen product using a skin-mimicking substrate (SMS). Among all thickeners examined (petrolatum, dextrin palmitate, silica silylate, and organoclay), organoclay and silica silylate significantly increased the UV absorbance of sunscreen on the SMS in a concentration-dependent manner. Thereafter, we examined film uniformity to elucidate the mechanism underlying the observed increase in UV absorption. The uniformity of film thickness on the SMS increased with increasing organoclay content, based on decreased standard deviations of film thickness. Our results showed that increasing the viscosity of the oil phase with organoclay resulted in the formation of a uniform film by preventing the sunscreen from flowing into the grooves when applied on the SMS, thereby increasing UV absorbance by more than two-fold that of sunscreen without organoclay. Thus, the use of thickeners, such as organoclay, increases the viscosity of the oil phase at a low shear rate after the high shear of application. This is an effective strategy for improving the overall quality and performance of sunscreen products.


Assuntos
Absorção Fisico-Química , Argila/química , Óleos/química , Pele Artificial , Protetores Solares/química , Raios Ultravioleta , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Viscosidade
9.
J Oleo Sci ; 69(9): 1117-1124, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32879199

RESUMO

4-tert-Butyl-4'-methoxydibenzoylmethane (BMDM) is widely used throughout the world as a highly effective UVA absorber that can prevent the progression of photoaging in skin. However, due to its low photostability, BMDM is also known for the disadvantage of having a reduced capability to absorb UVA during prolonged exposure to sunlight. Although many studies have been carried out to overcome this disadvantage of BMDM, little attention has been paid to how the radicals generated from BMDM during UV exposure influence the skin. Therefore, the purpose of this study was twofold: One goal was to clarify the influence of radicals on human skin using cytotoxicity as a parameter. The second was to propose a solution that could reduce the radical formation while taking photostability into consideration. Using ESR spin trapping and superoxide dismutase (SOD) treatment, the radicals produced by the UV exposure of BMDM were shown to be superoxide anion radicals (•O2-). HaCaT keratinocytes exposed to UVA in the presence of BMDM showed a significant reduction in cell viability, indicating that the radicals produced from BMDM have a harmful influence on the skin. UVA exposure coincidently led to a reduction of UVA absorbance by BMDM. Interestingly, 2-hydroxy-4-methoxybenzophenone (Benzophenone-3; BP3) reduced both the radical formation and the cytotoxicity resulting from the UVA-exposure of BMDM, while also restoring its UVA absorbance. In conclusion, the results show that BMDM and BP3 is an effective combination to reduce the influence of UVA-exposed BMDM on the skin and to prevent the loss of UVA absorbance by BMDM during UV exposure.


Assuntos
Benzofenonas/farmacologia , Chalconas/efeitos adversos , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Propiofenonas/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Luz Solar/efeitos adversos , Protetores Solares/farmacologia , Superóxidos/metabolismo , Raios Ultravioleta/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Interações Medicamentosas , Estabilidade de Medicamentos , Humanos , Propiofenonas/efeitos adversos , Envelhecimento da Pele/patologia , Protetores Solares/efeitos adversos , Fatores de Tempo
10.
J Cosmet Dermatol ; 15(2): 176-84, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27030543

RESUMO

BACKGROUND: A penta-peptide, Gly-Pro-Ile-Gly-Ser (GPIGS), promotes proliferation of mouse hair keratinocytes and accelerates hair growth in mice. AIM OF THIS STUDY: This study focused on the ability of the peptide to promote human hair growth. METHODS: We used a human hair keratinocyte proliferation assay and organ cultures of human hair follicle as in vitro systems. The lotions with and without the penta-peptide were administered to 22 Japanese men with androgenetic alopecia (AGA) for 4 months in a double-blind and randomized clinical study. RESULTS: The penta-peptide significantly stimulated the proliferation of human hair keratinocytes at a concentration of 2.3 µm (P < 0.01), and 5.0 µm of this peptide had a marked effect on hair shaft elongation in the organ culture (P < 0.05). The change in the proportion of thick hair (≥60 µm) compared to baseline in patients that received the peptide was significantly higher than in the placebo (P = 0.006). The change in the proportion of vellus hair (<40 µm) was also significantly lower in the peptide group than in the placebo (P = 0.029). The penta-peptide also significantly improved the appearance of baldness (P = 0.020) when blinded reviewers graded photographs of the participants according to a standardized baldness scale. No adverse dermatological effects due to treatment were noted during this clinical study. CONCLUSIONS: This penta-peptide promotes proliferation of human hair keratinocytes and hair shaft elongation of human hair follicles, in vitro. This peptide increases thick hair ratio in vivo, and this compound is useful for the improvement of AGA.


Assuntos
Alopecia/tratamento farmacológico , Folículo Piloso/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Oligossacarídeos/uso terapêutico , Administração Tópica , Adulto , Alopecia/diagnóstico , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dipeptídeos/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Seguimentos , Folículo Piloso/crescimento & desenvolvimento , Humanos , Japão , Queratinócitos/efeitos dos fármacos , Queratinócitos/fisiologia , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Valores de Referência , Fatores de Tempo , Resultado do Tratamento
11.
J Dermatol ; 43(5): 567-70, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26508659

RESUMO

Adenosine is an effective treatment for androgenetic alopecia (AGA) in Japanese men and women. Adenosine exerts its effects by significantly increasing the proportion of thick hair. In this study, we assessed the clinical outcome of adenosine treatment for 6 months in 38 Caucasian men. The change in proportion of thick hair (≥60 µm) compared with baseline in the adenosine group was significantly higher than that in the placebo group (P < 0.0001). The change in vellus hair proportion (<40 µm) was significantly lower in the adenosine group than that in the placebo group (P = 0.0154). The change in hair density compared with baseline of the adenosine group was also significantly higher compared with that of the placebo group (P = 0.0470). No adverse effects due to treatment were noted during this study by dermatological evaluation. Adenosine is effective in increasing the proportion of thick hair in Caucasian men with AGA as well as in Japanese men and women.


Assuntos
Adenosina/administração & dosagem , Alopecia/tratamento farmacológico , Cabelo/efeitos dos fármacos , Adenosina/efeitos adversos , Administração Tópica , Adulto , Método Duplo-Cego , Cabelo/anatomia & histologia , Cabelo/crescimento & desenvolvimento , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , População Branca
12.
J Invest Dermatol ; 132(10): 2342-2349, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22592156

RESUMO

Woolly hair (WH) is an abnormal variant of tightly curled hair, which is frequently associated with hypotrichosis. Non-syndromic forms of WH can show either autosomal-dominant WH (ADWH) or autosomal-recessive WH (ARWH) inheritance patterns. ARWH has recently been shown to be caused by mutations in either the lysophosphatidic acid receptor 6 (LPAR6) or lipase H (LIPH) gene. More recently, a mutation in the keratin K74 (KRT74) gene has been reported to underlie ADWH. Importantly, all of these genes are abundantly expressed in the inner root sheath (IRS) of human hair follicles. Besides these findings, the molecular mechanisms underlying hereditary WH have not been fully disclosed. In this study, we identified a Japanese family with ADWH and associated hypotrichosis. After exclusion of known causative genes, we discovered the heterozygous mutation c.422T>G (p.Phe141Cys) within the helix initiation motif of the IRS-specific keratin K71 (KRT71) gene in affected family members. We demonstrated that the mutant K71 protein led to disruption of keratin intermediate filament formation in cultured cells. To our knowledge, it is previously unreported that the KRT71 mutation is associated with a hereditary hair disorder in humans. Our findings further underscore the crucial role of the IRS-specific keratins in hair follicle development and hair growth in humans.


Assuntos
Motivos de Aminoácidos/genética , Doenças do Cabelo/congênito , Hipotricose/epidemiologia , Hipotricose/genética , Queratinas Específicas do Cabelo/genética , Mutação de Sentido Incorreto/genética , Sequência de Aminoácidos , Células Cultivadas , Pré-Escolar , Comorbidade , Feminino , Cabelo/crescimento & desenvolvimento , Doenças do Cabelo/epidemiologia , Doenças do Cabelo/genética , Folículo Piloso/citologia , Folículo Piloso/crescimento & desenvolvimento , Heterozigoto , Humanos , Dados de Sequência Molecular , Linhagem
13.
J Biomech ; 44(16): 2833-7, 2011 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-21924726

RESUMO

This paper reports on a small-scale bending method for human hair. The test sample, which is elliptical in cross-section, is fixed to a hollow steel needle using resin to form a cantilever. A loading probe is used to subject this to a lateral load, where the load is applied parallel to either the long or short axis of the elliptical cross-section. From these tests, load-displacement relationships for the hair were obtained. From the experimental data and analysis, we found that the structural elasticity determined is independent of the direction of bending, and precise measurements of the structural elasticity of human hair with scattering of less than 5% were realized using this test scheme. Finally, changes in the structural elasticity of hair due to hair treatments were detected and the changes are discussed based on a theoretical model of the multi-layered structure.


Assuntos
Elasticidade/fisiologia , Cabelo/fisiologia , Modelos Biológicos , Suporte de Carga/fisiologia , Humanos
14.
Tissue Eng ; 13(5): 975-82, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17341162

RESUMO

We have succeeded in culturing dermal papilla (DP) cells long term and developed new techniques that enhance their hair follicle-inducing efficiency in a patch assay. The outgrowing DP cells from mouse vibrissae were markedly stimulated by 10% fetal bovine serum-Dulbecco's modified essential medium that included fibroblast growth factor-2 (FGF-2). Moreover, the potency of proliferation was maintained during serial cultivations (more than 30 passages). We combined these established DP cells with epidermal cells and implanted them subcutaneously into athymic mice to examine their hair follicle-inducing ability. New hair follicles were induced by dissociated DP cells at earlier passages (under passage 4), but the cells from later passages could not induce follicles. We next aggregated the DP cells to form spheres and then injected them with epidermal cells. Unlike the dissociated DP cells, the spheres made from the later passaged cells (more than 10 passages) did induce new hair follicles. We examined several genes specific for DP of anagen follicles and confirmed that their expression level was elevated in the spheres compared with their expression level in adherent DP cells. These results suggest that FGF-2 is essential for dermal papilla cell culture and that sphere formation partially models the intact DP, resulting in hair follicle induction, even by later passaged cells.


Assuntos
Diferenciação Celular , Derme/citologia , Folículo Piloso/citologia , Esferoides Celulares/citologia , Esferoides Celulares/transplante , Vibrissas/citologia , Animais , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Derme/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Folículo Piloso/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Vibrissas/metabolismo
15.
J Invest Dermatol ; 127(6): 1318-25, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17301835

RESUMO

It has been previously reported that an adenosine receptor-mediated signal-transduction pathway in the dermal papilla cells (DPCs) of hair contributes to minoxidil-induced hair growth. In this study, we investigated this hypothesis further and have elucidated some underlying mechanisms. We performed DNA microarray analyses of DPCs and found that adenosine stimulation increases fibroblast growth factor-7 (FGF-7) gene expression levels by greater than 2-fold. Elevations of the extracellular FGF-7 protein levels were also observed. These upregulations of FGF-7 both at mRNA and protein levels were inhibited by A2b adenosine receptor-specific antagonist, alloxazine, but not by antagonists for other subtypes. In addition, the intracellular cAMP levels were raised by adenosine in a dose-dependent manner. Moreover, an increase of intracellular cAMP augmented the FGF-7 upregulation. Taken together, these results show that adenosine treatment of DPCs upregulates FGF-7 expression via the A2b adenosine receptor and that cAMP acts as one of the second messengers in this pathway. Furthermore, treatment with FGF-7 at concentrations of 10 ng/ml or greater significantly stimulated hair fiber elongation in human scalp hair follicle organ cultures. These data imply that adenosine might stimulate hair growth through FGF-7 upregulation in DPCs.


Assuntos
Adenosina/farmacologia , Fator 7 de Crescimento de Fibroblastos/genética , Folículo Piloso/citologia , Receptor A2B de Adenosina/metabolismo , Sistemas do Segundo Mensageiro/fisiologia , Adulto , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , AMP Cíclico/metabolismo , Fator 7 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Folículo Piloso/efeitos dos fármacos , Folículo Piloso/fisiologia , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Técnicas de Cultura de Órgãos , Couro Cabeludo/citologia , Couro Cabeludo/fisiologia , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia
16.
Mech Dev ; 123(11): 831-41, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16989989

RESUMO

The development, maintenance and regeneration of epithelial appendages such as hairs or vibrissae depend on reciprocal interactions between the epidermal and the dermal components of the integument. Growth factors are among a number of signaling molecules that have been identified during these developmental events. Growth factors such as fibroblast growth factors (FGFs) bind cell surface heparan sulfate proteoglycans (HSPGs) on their heparan sulfate side chains and as such these proteoglycans act as co-receptors for FGF receptors (FGFRs) by forming a ternary signaling complex of HSPG, FGFR and FGF. The syndecans make up a family (syndecan-1-4) of transmembrane HSPGs. In the present study we examined the growth response of mouse vibrissae to HSPG-binding growth factors as a function of the presence or absence of syndecan-4 in an organ culture system. Syndecan-4 is expressed on keratinocytes that make up the inner root sheath of the vibrissa. Vibrissae from wild-type mice, but not from syndecan-4 null mice, displayed a statistically significant and dose-dependent growth response to FGF-1, FGF-2 and FGF-7. In contrast, a statistically significant growth response is seen in vibrissae from both wild-type and syndecan-4 null mice when the culture medium is supplemented with either hepatocyte growth factor (HGF) that binds to HSPG, insulin that does not bind to HSPG or 5% fetal bovine serum. The syndecan-4 dependent effect of FGF-1, -2 and -7 on the transcriptional activity of IRS expressed genes and of genes involved in cell proliferation reveals a number of different response patterns. In vivo, the vibrissae of syndecan-4 null mice are shorter and have a smaller diameter than those of wild-type mice and this phenotype may result from a suboptimal response to growth factors. Syndecan-1, which is expressed in the outer root sheath of the vibrissae shaft, does not influence the response of the vibrissae to FGF-1, -2 and -7 and the length and diameter of vibrissae of syndecan-1 null mice do not differ from those of wild-type mice.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Sindecana-4/metabolismo , Vibrissas/crescimento & desenvolvimento , Vibrissas/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Camundongos , RNA Mensageiro/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Sindecana-4/classificação , Sindecana-4/genética , Vibrissas/embriologia
17.
Glycoconj J ; 19(4-5): 305-13, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12975609

RESUMO

Studies examining the role of the cell-surface heparan sulfate proteoglycan syndecan-4 have yielded a plethora of information regarding its role in both cell-matrix and growth-factor mediated signaling events. Many of the initial conclusions drawn from such research placed syndecan-4 in a keystone position within various signaling pathways though the generation of syndecan-4 null mice have surprised many in the field by indicating otherwise. These contradictory results place researchers in the frustrating and yet exhilarating position of still asking the question, "What role does syndecan-4 play in life?"


Assuntos
Glicoproteínas de Membrana/fisiologia , Proteoglicanas/fisiologia , Animais , Movimento Celular , Adesões Focais , Expressão Gênica , Substâncias de Crescimento/fisiologia , Proteoglicanas de Heparan Sulfato/fisiologia , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Proteína Quinase C/fisiologia , Proteoglicanas/deficiência , Proteoglicanas/genética , Transdução de Sinais , Sindecana-4
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