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1.
Int J Cosmet Sci ; 45(1): 1-13, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35984685

RESUMO

OBJECTIVE: An important factor in the aging of the face is a reduction in the volume of adipose tissue. This reduction in adipose tissue contributes to decreased skin elasticity, which is also part of the aging process. Overall, these lead to wrinkle formation. Fat injection is a common means of addressing this issue and is used to reduce the effects of aging on the face and to increase the fullness of the lips and breasts. However, fat injection is an invasive surgical procedure. This study aimed to discover novel cosmetic ingredients that increase the volume of subcutaneous (pre)adipocytes to create the appearance of more youthful skin. METHODS: We focused on the number of subcutaneous preadipocytes and the accumulation of lipid droplets. To discover natural ingredients that increase both of these, extracts of 380 natural products were prepared and screened for their effects on both growth and differentiation (i.e., lipid droplet accumulation) of human subcutaneous preadipocytes. One extract was found to have the desired effects, and this was further studied to determine the active compounds. We then evaluated its efficacy in a human clinical study. RESULTS: We found that Arnica montana L. flower extract (AFE) accelerates both the growth and the differentiation of human subcutaneous preadipocytes. AFE was found to significantly increase the volume of adipocyte spheroids. The active compounds 6-O-methacryloylhelenalin and 6-O-isobutyrylhelenalin were found to be responsible for the effects of AFE on preadipocytes. In a human clinical study, gels containing 1% AFE successfully enhanced the volume of the lips and face with reduction of wrinkles with no adverse reactions. CONCLUSION: This is the first report to demonstrate that AFE and the included compounds, 6-O-methacryloylhelenalin and 6-O-isobutyrylhelenalin, act on preadipocytes. AFE would be ideal for use in products that plump the face to reduce wrinkles and create a more youthful appearance.


OBJECTIF: Un facteur important du vieillissement du visage réside dans la réduction du volume du tissu adipeux. Cette réduction du tissu adipeux contribue à une diminution de l'élasticité de la peau qui fait également partie du processus de vieillissement. Globalement, ces facteurs induisent la formation des rides. L'injection de graisse est un moyen courant pour remédier à ce problème et sert à réduire les effets du vieillissement sur le visage et à augmenter la plénitude des lèvres et des seins. Cependant, l'injection de graisse est une intervention chirurgicale invasive. Cette étude visait à découvrir des ingrédients cosmétiques innovants qui augmentent le volume des (pré)adipocytes sous-cutanés pour créer l'apparence d'une peau plus jeune. MÉTHODES: Nous avons mis l'accent sur le nombre de préadipocytes sous-cutanés et sur l'accumulation de gouttelettes lipidiques. Pour découvrir des ingrédients naturels qui augmentent ces deux facteurs, des extraits de 380 produits naturels ont été préparés et analysés en vue de la détermination de leurs effets sur la croissance et la différenciation (c'est-à-dire l'accumulation de gouttelettes lipidiques) des préadipocytes humains sous-cutanés. Un extrait s'est avéré avoir les effets escomptés et il a fait l'objet d'études approfondies visant à déterminer les composés actifs. Nous avons ensuite évalué son efficacité dans une étude clinique chez l'homme. RÉSULTATS: Nous avons découvert que l'extrait de fleur de l'Arnica montana L. (AFE) accélère à la fois la croissance et la différenciation des préadipocytes humains sous-cutanés. L'AFE s'est avéré augmenter considérablement le volume des sphéroïdes des adipocytes. Les composés actifs 6-Ométhacryloyl-hélénaline et 6-O-isobutyryl-hélénaline se sont avérés responsables des effets de l'AFE sur les préadipocytes. Dans une étude clinique chez l'homme, des gels contenant 1 % d'AFE ont permis d'améliorer le volume des lèvres et du visage avec une réduction des rides sans effets indésirables. CONCLUSION: Il s'agit du premier rapport démontrant que l'AFE et les composés inclus, 6-O-méthacryloyl-hélénaline et 6-O-isobutyryl-hélénaline, agissent sur les préadipocytes. L'AFE serait idéal pour les produits qui repulpent le visage afin de réduire les rides et de donner un aspect rajeuni.


Assuntos
Arnica , Humanos , Tecido Adiposo , Adipócitos , Pele , Extratos Vegetais/farmacologia , Diferenciação Celular
2.
Food Sci Nutr ; 10(2): 577-583, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35154693

RESUMO

This study investigated the effects of salmon nasal cartilage proteoglycan (PG), which shows anti-inflammatory properties, on obesity induced by high-fat diet (HFD) in a mouse model. Mice were fed either a HFD or normal diet (ND), with or without PG, for 8-12 weeks. After 12 weeks, the body weight of mice fed with PG-free HFD was 54.08 ± 4.67 g, whereas that of mice fed with HFD containing PG was 41.83 ± 4.97 g. The results suggest that the increase in body weight was attenuated in mice fed with HFD containing PG. This effect was not observed in mice fed with ND. The PG administration suppressed the elevation of serum lipids (the level of serum lipids ranged between 54% and 69% compared to 100% in mice fed with PG-free HFD) and the upregulated mRNA expression of sterol regulatory element-binding protein-1c (SREBP-1c), which is a transcription factor that acts as a master regulator of lipogenic gene expression in the liver (the expression level was 77.5% compared to 100% in mice fed with PG-free HFD). High leptin levels in mice fed with PG-free HFD were observed during fasting (average at 14,376 ng/ml), and they did not increase after refeeding (average of 14,263 ng/ml), whereas serum leptin levels in mice fed with HFD containing PG were low during fasting (average of 6481 ng/ml) and increased after refeeding (average 13,382 ng/ml). These results suggest that PG feeding has an anti-obesity effect and that the regulation of SREBP-1c and leptin secretion play a role in this effect.

3.
Int J Cosmet Sci ; 44(2): 154-165, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35133683

RESUMO

OBJECTIVE: Hair loss and greying affect men and women of all ages, often causing psychosocial difficulties. Dickkopf-1 (DKK1), a major hair loss factor secreted from dermal papilla (DP) cells in response to the secretion of dihydrotestosterone (DHT), has been reported to induce and accelerate androgenetic alopecia (AGA). In addition, DKK1 acts as a potent suppressor of melanogenesis and is closely related to hair colour. R-spondin 1 (RSPO1) is a secretory agonist of Wnt signalling known to antagonize the effects of DKK1, including DKK1-mediated hair follicle suppression. In this study, we investigated the effect of watercress extract (WCE) on the secretion of RSPO1 and DKK1 from DP cells as well as its anti-hair loss effect in human hair follicles and patients. METHODS: The in vitro secretion of RSPO1 and DKK1 was measured by ELISA. Human hair follicles were collected from the scalp of a female donor and used for ex vivo organ culture to investigate the effects of WCE on human hair loss. Finally, a 6-month human clinical trial was conducted to examine the effect of WCE-containing lotion on hair growth in a male panel. RESULTS: WCE significantly upregulated RSPO1 secretion and suppressed DKK1 secretion in a dose-dependent manner, even in the presence of DHT. WCE-treated hair follicles elongated 1.6-fold compared with the control, and the level of RSPO1 production in DP as well as RSPO1 bound to the outer root sheath (ORS) increased. In the clinical trial, the hair lotion containing 2% WCE increased hair thickness and density to improve against hair loss symptoms. CONCLUSION: WCE exhibited a strong anti-androgenic effect through its ability to suppress DKK1 secretion and antagonize DKK1 via RSPO1. These findings highlighted the potential use of WCE for the treatment of hair loss.


OBJECTIF: La perte de cheveux et le grisonnement touchent des hommes et des femmes de tous âges, ce qui entraîne souvent des difficultés psychosociales. Selon des rapports, Dickkopf-1 (DKK1), un facteur de perte de cheveux majeur sécrété par les cellules de la papille dermique (PD) en réponse à la sécrétion de dihydrotestostérone (DHT), induit et accélère l'alopécie androgénétique (AAG). En outre, DKK1 agit comme un puissant suppresseur de la mélanogenèse et est étroitement lié à la couleur des cheveux. La protéine R-spondin 1 (RSPO1) est un agoniste sécrétoire de la voie de signalisation Wnt connue pour antagoniser les effets de DKK1, notamment la suppression des follicules pileux médiée par DKK1. Dans cette étude, nous avons étudié l'effet de l'extrait de cresson sur la sécrétion de RSPO1 et de DKK1 à partir des cellules de la PD, ainsi que son effet anti-perte de cheveux sur les follicules pileux humains et chez les patients. MÉTHODES: La sécrétion in vitro de RSPO1 et de DKK1 a été mesurée à l'aide de la méthode ELISA. Des follicules pileux humains ont été prélevés sur le cuir chevelu d'une femme et utilisés pour une culture d'organes ex vivo afin d'étudier les effets de l'extrait de cresson sur la perte de cheveux humains. Enfin, un essai clinique de 6 mois chez l'être humain a été mené pour examiner l'effet d'une lotion contenant de l'extrait de cresson sur la croissance des cheveux au sein d'un panel d'hommes. RÉSULTATS: L'extrait de cresson a significativement régulé à la hausse la sécrétion de RSPO1 et a supprimé la sécrétion de DKK1 de manière dose-dépendante, même en présence de DHT. Les follicules pileux traités avec de l'extrait de cresson ont été multipliés par 1,6 par rapport au groupe témoin, et le niveau de production de RSPO1 dans la PD ainsi que le taux de RSPO1 lié à la gaine externe de la racine ont augmenté. Dans l'essai clinique, la lotion pour cheveux contenant 2 % d'extrait de cresson a augmenté l'épaisseur et la densité des cheveux, améliorant ainsi les symptômes de perte de cheveux. CONCLUSION: La capacité de l'extrait de cresson à supprimer la sécrétion de DKK1 et à antagoniser DKK1 via la protéine RSPO1 lui a conféré un effet anti-androgénique puissant. Ces résultats ont mis en évidence le potentiel de l'extrait de cresson pour le traitement de la perte de cheveux.


Assuntos
Alopecia , Folículo Piloso , Alopecia/tratamento farmacológico , Feminino , Cabelo , Humanos , Masculino , Extratos Vegetais/farmacologia , Couro Cabeludo/metabolismo
4.
J Pharmacol Sci ; 148(1): 162-171, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34924122

RESUMO

Alzheimer's disease (AD) is characterized by progressive cognitive decline, and the number of affected individuals has increased worldwide. However, there are no effective treatments for AD. Therefore, it is important to prevent the onset of dementia. Oxidative stress and endoplasmic reticulum (ER) stress are increased in the brains of AD patients, and are postulated to induce neuronal cell death and cognitive dysfunction. In this study, Centella asiatica, a traditional Indian medicinal herb, were fractionated and compared for their protective effects against glutamate and tunicamycin damage. Araliadiol was identified as a component from the fraction with the highest activity. Further, murine hippocampal cells (HT22) were damaged by glutamate, an oxidative stress inducer. C. asiatica and araliadiol suppressed cell death and reactive oxygen species production. HT22 cells were also injured by tunicamycin, an ER stress inducer. C. asiatica and araliadiol prevented cell death by mainly inhibiting PERK phosphorylation; additionally, C. asiatica also suppressed the expression levels of GRP94 and BiP. In Y-maze test, oral administration of araliadiol (10 mg/kg/day) for 7 days ameliorated the arm alternation ratio in mice with scopolamine-induced cognitive impairment. These results suggest that C. asiatica and its active component, araliadiol, have neuroprotective effects, which may prevent cognitive dysfunction.


Assuntos
Morte Celular/efeitos dos fármacos , Centella/química , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fármacos Neuroprotetores , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Triterpenos/administração & dosagem , Triterpenos/farmacologia , Administração Oral , Animais , Células Cultivadas , Chaperona BiP do Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Hipocampo/citologia , Hipocampo/patologia , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Triterpenos/isolamento & purificação , eIF-2 Quinase/metabolismo
5.
Int J Mol Sci ; 22(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34681829

RESUMO

Endothelial cells acquire different phenotypes to establish functional vascular networks. Vascular endothelial growth factor (VEGF) signaling induces endothelial proliferation, migration, and survival to regulate vascular development, which leads to the construction of a vascular plexuses with a regular morphology. The spatiotemporal localization of angiogenic factors and the extracellular matrix play fundamental roles in ensuring the proper regulation of angiogenesis. This review article highlights how and what kinds of extracellular environmental molecules regulate angiogenesis. Close interactions between the vascular and neural systems involve shared molecular mechanisms to coordinate developmental and regenerative processes. This review article focuses on current knowledge about the roles of angiogenesis in peripheral nerve regeneration and the latest therapeutic strategies for the treatment of peripheral nerve injury.


Assuntos
Células Endoteliais/fisiologia , Matriz Extracelular/fisiologia , Neovascularização Fisiológica , Regeneração Nervosa , Nervos Periféricos/fisiologia , Transdução de Sinais , Indutores da Angiogênese/metabolismo , Animais , Proliferação de Células , Humanos , Traumatismos dos Nervos Periféricos/metabolismo , Fatores de Crescimento do Endotélio Vascular/fisiologia
6.
Int J Mol Sci ; 22(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34639184

RESUMO

Glycoprotein non-metastatic melanoma protein B (GPNMB) is a type I transmembrane glycoprotein that plays an important role in cancer metastasis and osteoblast differentiation. In the skin epidermis, GPNMB is mainly expressed in melanocytes and plays a critical role in melanosome formation. In our previous study, GPNMB was also found to be expressed in skin epidermal keratinocytes. In addition, decreased GPNMB expression was observed in the epidermis of lesional skin of patients with vitiligo. However, the exact role of keratinocyte-derived GPNMB and its effect on vitiligo is still unknown. In this study, we demonstrated that GPNMB expression was also decreased in rhododendrol-induced leukoderma, as seen in vitiligo. The extracellular soluble form of GPNMB (sGPNMB) was found to protect melanocytes from cytotoxicity and the impairment of melanogenesis induced by oxidative stress. Furthermore, the effect of rGPNMB was not altered by the knockdown of CD44, which is a well-known receptor of GPNMB, but accompanied by the suppressed phosphorylation of AKT but not ERK, p38, or JNK. In addition, we found that oxidative stress decreased both transcriptional GPNMB expression and sGPNMB protein expression in human keratinocytes. Our results suggest that GPNMB might provide novel insights into the mechanisms related to the pathogenesis of vitiligo and leukoderma.


Assuntos
Queratinócitos/efeitos dos fármacos , Melaninas/metabolismo , Melanócitos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Glicoproteínas de Membrana/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/metabolismo , Melanoma/patologia , Glicoproteínas de Membrana/genética , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
7.
J Nat Med ; 75(3): 623-632, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33830449

RESUMO

The anti-inflammatory effects of a 50% aqueous extract of Rosa roxburghii fruit (RRFE) and two ellagitannins (strictinin and casuarictin) isolated from the RRFE were evaluated in a cell model of skin inflammation induced by self-RNA released from epidermal cells damaged by UV ray (UVR) irradiation. The RRFE inhibited interleukin-8 (IL-8) mRNA expression in normal human epidermal keratinocytes (NHEKs) stimulated with polyinosinic:polycytidylic acid (poly(I:C)), a ligand of toll-like receptor-3 (TLR-3). The plant-derived anti-inflammatory agents, dipotassium glycyrrhizinate (GK2) and allantoin, had no influence on the IL-8 expression. The purified compounds, strictinin and casuarictin, inhibited the IL-8 mRNA expression and IL-8 release induced in NHEKs by poly(I:C). These ellagitannins were thus found to be responsible for the biological activity exhibited by the RRFE. This study demonstrates that RRFE and isolated RRFE compounds show promise as ingredients for products formulated to improve skin disorders induced by UVR irradiation.


Assuntos
Taninos Hidrolisáveis/farmacologia , Interleucina-8/biossíntese , Queratinócitos/efeitos dos fármacos , Rosa/química , Compostos de Bifenilo , Células Cultivadas , Frutas/química , Ácido Gálico/análogos & derivados , Humanos , Queratinócitos/metabolismo , Fenóis , Poli I-C/farmacologia , Raios Ultravioleta
8.
Biosci Biotechnol Biochem ; 85(3): 493-501, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33589895

RESUMO

The Asian traditional medicinal plant Acorus calamus and its component α-asarone exhibited various biological activities, such as antiinflammation and antioxidant effects. In the present study, we investigated the in vitro effects of A. calamus extract and α-asarone on oxidative stress- and endoplasmic reticulum (ER) stress-induced cell death in hippocampal HT22 cells. A. calamus extract and α-asarone both significantly suppressed cell death induced by the oxidative stress inducer l-glutamate and ER stress inducer tunicamycin. A. calamus extract and α-asarone also significantly reduced reactive oxygen species (ROS) production induced by l-glutamate. Moreover, A. calamus extract and α-asarone suppressed the phosphorylation of protein kinase RNA-like ER kinase (PERK) induced by tunicamycin. These results suggest that A. calamus extract and α-asarone protect hippocampal cells from oxidative stress and ER stress by decreasing ROS production and suppressing PERK signaling, respectively. α-Asarone has potential as a potent therapeutic candidate for neurodegenerative diseases, including Alzheimer's disease.


Assuntos
Acorus/química , Derivados de Alilbenzenos/farmacologia , Anisóis/farmacologia , Antibacterianos/farmacologia , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tunicamicina/farmacologia , Animais , Linhagem Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hipocampo/citologia , Camundongos , Neurônios/citologia , Fosforilação , Espécies Reativas de Oxigênio/metabolismo
9.
Sci Rep ; 10(1): 4930, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188902

RESUMO

GPNMB is involved in multiple cellular functions including cell adhesion, stress protection and stem cell maintenance. In skin, melanocyte-GPNMB is suggested to mediate pigmentation through melanosome formation, but details of keratinocyte-GPNMB have yet to be well understood. We confirmed the expression of GPNMB in normal human epidermal keratinocytes (NHEKs) by reducing the expression using siRNA. A higher calcium concentration of over 1.25 mM decreased the GPNMB expression. Histological staining showed that GPNMB was expressed in the basal layer of normal skins but completely absent in vitiligo skins. The normal expression of GPNMB in nevus depigmentosus skin suggested that lack of GPNMB is characteristic of vitiligo lesional skins. IFN-γ and IL-17A, two cytokines with possible causal roles in vitiligo development, inhibited GPNMB expression in vitro. Approximately 4-8% of the total GPNMB expressed on NHEKs were released possibly by ADAM 10 as a soluble form, but the process of release was not affected by the cytokines. The suppressive effect of IFN-γ on GPNMB was partially via IFN-γ/JAK2/STAT1 signaling axis. Decreased GPNMB expression in keratinocytes may affect melanocyte maintenance or survival against oxidative stress although further studies are needed. These findings indicate a new target for vitiligo treatment, focusing on the novel role of IFN-γ and IL-17 in downregulating keratinocyte-GPNMB.


Assuntos
Regulação da Expressão Gênica , Queratinócitos/metabolismo , Glicoproteínas de Membrana/genética , Vitiligo/genética , Proteínas ADAM/antagonistas & inibidores , Proteínas ADAM/metabolismo , Cálcio/metabolismo , Adesão Celular , Citocinas/metabolismo , Epiderme/metabolismo , Epiderme/patologia , Humanos , Janus Quinase 2/metabolismo , Glicoproteínas de Membrana/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , Vitiligo/metabolismo , Vitiligo/patologia
10.
J Nat Med ; 73(1): 114-123, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30218207

RESUMO

Periodontal diseases are a major public health problem affecting over half of the adult population worldwide. Lipopolysaccharide (LPS) produced by the periodontopathic bacterium Porphyromonas gingivalis induces the expression of inflammatory cytokines that promote inflammatory bone destruction. Mounting evidence supports that periodontal diseases are involved in the onset and progression of several systemic diseases, such as aspiration pneumonia and diabetes. Although treatment of periodontal diseases by removing the periodontopathic bacteria by brushing is a standard practice, it has limitations and is not effective in all cases. Therefore, a new method to replace or complement brushing is needed for the treatment of periodontal diseases. In this study, we investigated the anti-inflammatory effects of an extract from Cynara scolymus L. and its pharmacologically effective compound cynaropicrin, a sesquiterpene lactone, on human gingival fibroblasts (HGFs) stimulated by LPS and the potential anti-osteoclastogenic effects on RAW264.7 cells induced by receptor activator of NF-κB ligand (RANKL). We found that cynaropicrin inhibited IL-8 and IL-6 mRNA and protein synthesis in LPS-stimulated HGFs in a dose-dependent manner. P. gingivalis LPS-induced degradation of IκBα and phosphorylation of NF-κB p65 were also suppressed by cynaropicrin, as was LPS-stimulated NF-κB transactivation. Thus, cynaropicrin's inhibition of P. gingivalis LPS-induced IL-8 and IL-6 expression may be due to the inhibition of the NF-κB pathway. Furthermore, we showed that cynaropicrin dramatically reduced RANKL-induced osteoclast differentiation. These results suggest that cynaropicrin may be useful for preventing periodontal diseases and could prove valuable in the development of more effective preventative approaches for periodontal diseases.


Assuntos
Cynara scolymus/química , Citocinas/metabolismo , Fibroblastos/efeitos dos fármacos , Lactonas/farmacologia , Osteoclastos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Diferenciação Celular , Células Cultivadas , Fibroblastos/citologia , Gengiva/citologia , Humanos , Lipopolissacarídeos , Camundongos , Osteoclastos/citologia , Fosforilação , Porphyromonas gingivalis , Ligante RANK , Células RAW 264.7 , Fator de Transcrição RelA/metabolismo , Ativação Transcricional
11.
Sci Rep ; 5: 14579, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26417724

RESUMO

The production of melanin is regulated by α-melanocyte-stimulating hormone (α-MSH), which is produced from proopiomelanocortin (POMC). Keratinocytes release POMC along with lower levels of α-MSH and ACTH. To clarify the mechanism of melanogenesis after ultraviolet (UV)-irradiation, this study focused on the expression of POMC and POMC-derived peptides after UV-irradiation. Western blot analysis and immunoassays indicated that both POMC and α-MSH-like immunoreactivity (α-MSH-LI) increased after UV-irradiation. However, other POMC-derived products were very low. In hypophysectomized mice, α-MSH-LI increased to the same level as in control mice after UV-irradiation. Structural analysis revealed that the major α-MSH-LI product was ACTH(1-8). Furthermore, ACTH(1-8) competed with [(125)I]-α-MSH for receptor binding and increased melanin production via a melanocortin-1 receptor. These results suggested that melanin was produced through ACTH(1-8) after UV-irradiation. Trypsin-like enzymatic activity, which is responsible for POMC activation, increased after UV-irradiation and was identified as tryptase. In mast cell-deficient mice, which do not produce tryptase, α-MSH-LI levels were unchanged after UV-irradiation. The present study demonstrates the production of ACTH(1-8) from POMC by tryptase, which is a novel peptide-processing mechanism in the extracellular compartment of the skin.


Assuntos
Pavilhão Auricular , Melaninas/biossíntese , Pró-Opiomelanocortina/metabolismo , Pele/metabolismo , Pele/efeitos da radiação , Raios Ultravioleta , Hormônio Adrenocorticotrópico/química , Hormônio Adrenocorticotrópico/farmacologia , Animais , Espaço Extracelular/metabolismo , Masculino , Mastócitos/imunologia , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/química , Peptídeos/imunologia , Peptídeos/metabolismo , Ligação Proteica , Receptor Tipo 1 de Melanocortina/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , alfa-MSH/imunologia , alfa-MSH/metabolismo
12.
Curr Drug Metab ; 11(5): 431-5, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20540695

RESUMO

The skin photoaging is an inevitable process that occurs in daily life. It ischaracterized by acceralated keratinocyte proliferation and degradation of collagen fibers, causing skin wrinkling and laxity, and melanocyte proliferation that leads to pigmentation. Ultraviolet (UV) is considered to be a major cause of such skin changes. It is well established that nuclear factor kappa B (NF-kappaB) is activated upon UV irradiation and induces various genes including interleukin-1 (IL-1), tumor necrosis factor alpha (TNFalpha), and matrix metalloprotease-1 (MMP-1). It is also known that production of basic fibroblast growth factor (bFGF) is induced in skin tissues by UV irradiation and it promotes the proliferation of skin keratinocytes and melanocytes. We found that either UVB, IL-1 or TNFalpha could induce NF-kappaB by activating its signal transduction pathway. The activated NF-kappaB produces MMP-1 and bFGF in skin fibroblasts and human keratinocyte cell line HaCaT. In this experiment, we examined whether parthenolide and magnolol, NF-kappaB inhibitors, could block such UVB-mediated skin changes. We found that either parthenolide or magnolol could effectively inhibit the gene expression mediated by NF-kappaB and the production of bFGF and MMP-1 from cells overexpressing p65, a major subunit of NF-kappaB. We also found that these NF-kappaB inhibitors could inhibit the UVB-induced proliferation of keratinocytes and melanocytes in the mouse skin. These findings suggest that NF-kappaB inhibitors are useful in preventing the skin photoaging.


Assuntos
NF-kappa B/antagonistas & inibidores , NF-kappa B/fisiologia , Envelhecimento da Pele/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/fisiopatologia , Pele/efeitos da radiação , Envelhecimento da Pele/patologia , Raios Ultravioleta/efeitos adversos
13.
Arch Dermatol Res ; 300 Suppl 1: S69-76, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17968569

RESUMO

Mast cells are widely distributed in the connective tissue of the body, but are particularly prominent in tissues such as skin. An increased number of mast cells can be found in the dermis under inflammatory conditions and ultraviolet (UV) exposed skin. Previous investigations have identified matrix metalloproteinases (MMPs) as key enzymes in the degradation of extra cellular matrix (ECM). This study reports about the potential contribution of human mast cell tryptase as a new triggering enzyme in matrix degradation process. Recent studies suggest that mast cell-derived proteases can activate MMPs. We investigated both the degradation of cellular matrix components and activation of MMPs by human tryptase. Mast cells are increased in photoaged skin and the increase of mast cell tryptase in UV irradiated skin was confirmed. Human mast cell tryptase was purified from human tonsils by a series of standard chromatographic procedures. Degradation of collagen type I was achieved by incubation of human type I collagen with tryptase and the fragments were quantified by SDS-PAGE and staining with Coomassie Brilliant Blue 250-R (CBB). Treatment with tryptase resulted in the activation of proMMP-9 as revealed by gelatinolytic activity in type IV collagen zymography. When tryptase was incubated with human type IV collagen, gradual degradation of intact collagen was detected by Western blotting. Furthermore, type IV collagen degradation was observed in the basement membrane (BM) of a three-dimensional (3D) skin model. Degranulation of mast cells, which release tryptase, can activate MMPs and causes direct damage to ECM proteins. These findings strongly implicate that tryptase either alone or in conjunction with activation of MMPs, can participate in ECM damage and the possible destruction of BM leading to photoaging.


Assuntos
Membrana Basal/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas de Membrana/metabolismo , Envelhecimento da Pele , Triptases/fisiologia , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo IV/metabolismo , Precursores Enzimáticos/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Pelados , Pele/efeitos da radiação
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