Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 11.854
Filtrar
1.
PLoS One ; 15(9): e0239625, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966340

RESUMO

During alcohol consumption, the esophageal mucosa is directly exposed to high concentrations of ethanol (EtOH). We therefore investigated the response of normal human esophageal epithelial cell lines EPC1, EPC2 and EPC3 to acute EtOH exposure. While these cells were able to tolerate 2% EtOH for 8 h in both three-dimensional organoids and monolayer culture conditions, RNA sequencing suggested that EtOH induced mitochondrial dysfunction. With EtOH treatment, EPC1 and EPC2 cells also demonstrated decreased mitochondrial ATPB protein expression by immunofluorescence and swollen mitochondria lacking intact cristae by transmission electron microscopy. Mitochondrial membrane potential (ΔΨm) was decreased in a subset of EPC1 and EPC2 cells stained with ΔΨm-sensitive dye MitoTracker Deep Red. In EPC2, EtOH decreased ATP level while impairing mitochondrial respiration and electron transportation chain functions, as determined by ATP fluorometric assay, respirometry, and liquid chromatography-mass spectrometry. Additionally, EPC2 cells demonstrated enhanced oxidative stress by flow cytometry for mitochondrial superoxide (MitoSOX), which was antagonized by the mitochondria-specific antioxidant MitoCP. Concurrently, EPC1 and EPC2 cells underwent autophagy following EtOH exposure, as evidenced by flow cytometry for Cyto-ID, which detects autophagic vesicles, and immunoblots demonstrating induction of the lipidated and cleaved form of LC3B and downregulation of SQSTM1/p62. In EPC1 and EPC2, pharmacological inhibition of autophagy flux by chloroquine increased mitochondrial oxidative stress while decreasing cell viability. In EPC2, autophagy induction was coupled with phosphorylation of AMP activated protein kinase (AMPK), a cellular energy sensor responding to low ATP levels, and dephosphorylation of downstream substrates of mechanistic Target of Rapamycin Complex (mTORC)-1 signaling. Pharmacological AMPK activation by AICAR decreased EtOH-induced reduction of ΔΨm and ATP in EPC2. Taken together, acute EtOH exposure leads to mitochondrial dysfunction and oxidative stress in esophageal keratinocytes, where the AMPK-mTORC1 axis may serve as a regulatory mechanism to activate autophagy to provide cytoprotection against EtOH-induced cell injury.


Assuntos
Autofagia , Esôfago/citologia , Queratinócitos/metabolismo , Mitocôndrias/metabolismo , Estresse Oxidativo , Animais , Linhagem Celular , Células Cultivadas , Etanol/farmacologia , Feminino , Queratinócitos/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
2.
Adv Exp Med Biol ; 1268: 285-306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32918224

RESUMO

Cutaneous malignancies including melanomas and keratinocyte carcinomas (KC) are the most common types of cancer, occurring at a rate of over one million per year in the United States. KC, which include both basal cell carcinomas and squamous cell carcinomas, are substantially more common than melanomas and form the subject of this chapter. Ultraviolet radiation (UVR), both UVB and UVA, as occurs with sunlight exposure is generally regarded as causal for these malignancies, but UVB is also required for vitamin D synthesis in the skin. Keratinocytes are the major cell in the epidermis. These cells not only produce vitamin D but contain the enzymatic machinery to metabolize vitamin D to its active metabolite, 1,25(OH)2D, and express the receptor for this metabolite, the vitamin D receptor (VDR). This allows the cell to respond to the 1,25(OH)2D that it produces. Based on our own data and that reported in the literature, we conclude that vitamin D signaling in the skin suppresses UVR-induced epidermal tumor formation. In this chapter we focus on four mechanisms by which vitamin D signaling suppresses tumor formation. They are inhibition of proliferation/stimulation of differentiation with discussion of the roles of hedgehog, Wnt/ß-catenin, and hyaluronan/CD44 pathways in mediating vitamin D regulation of proliferation/differentiation, regulation of the balance between oncogenic and tumor suppressor long noncoding RNAs, immune regulation, and promotion of DNA damage repair (DDR).


Assuntos
Receptores de Calcitriol/metabolismo , Pele/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Humanos , Queratinócitos/metabolismo , Pele/citologia , Neoplasias Cutâneas/metabolismo , Raios Ultravioleta/efeitos adversos , Vitamina D/metabolismo
3.
PLoS One ; 15(8): e0238076, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857768

RESUMO

Epidermal lineages and injury induced regeneration are controlled by transcriptional programs coordinating cellular signaling and epigenetic regulators, but the mechanism remains unclear. Previous studies showed that conditional deletion of the transcriptional coactivator Mediator 1 (Med1) changes epidermal lineages and accelerates wound re-epithelialization. Here, we studied a molecular mechanism by which Med1 facilitates these processes, in particular, by focusing on TGFß signaling through genome wide transcriptome analysis. The expression of the TGF ligands (Tgfß1/ß2) and their downstream target genes is decreased in both normal and wounded Med1 null skin. Med1 silencing in cultured keratinocytes likewise reduces the expression of the ligands (TGFß1/ß2) and diminishes activity of TGFß signaling as shown by decreased p-Smad2/3. Silencing Med1 increases keratinocyte proliferation and migration in vitro. Epigenetic studies using chromatin immuno-precipitation and next generation DNA sequencing reveals that Med1 regulates transcription of TGFß components by forming large clusters of enhancers called super-enhancers at the regulatory regions of the TGFß ligand and SMAD3 genes. These results demonstrate that Med1 is required for the maintenance of the TGFß signaling pathway. Finally, we show that pharmacological inhibition of TGFß signaling enhances epidermal lineages and accelerates wound re-epithelialization in skin similar to that seen in the Med1 null mice, providing new insights into epidermal regeneration.


Assuntos
Subunidade 1 do Complexo Mediador/genética , Regeneração/fisiologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Animais , Linhagem da Célula , Movimento Celular , Proliferação de Células , Regulação para Baixo , Epiderme/fisiologia , Queratinócitos/citologia , Queratinócitos/metabolismo , Subunidade 1 do Complexo Mediador/antagonistas & inibidores , Subunidade 1 do Complexo Mediador/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Pele/metabolismo , Pele/patologia , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta2/genética , Regulação para Cima
4.
Nat Commun ; 11(1): 4239, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32843640

RESUMO

How stem cells give rise to epidermis is unclear despite the crucial role the epidermis plays in barrier and appendage formation. Here we use single cell-RNA sequencing to interrogate basal stem cell heterogeneity of human interfollicular epidermis and find four spatially distinct stem cell populations at the top and bottom of rete ridges and transitional positions between the basal and suprabasal epidermal layers. Cell-cell communication modeling suggests that basal cell populations serve as crucial signaling hubs to maintain epidermal communication. Combining pseudotime, RNA velocity, and cellular entropy analyses point to a hierarchical differentiation lineage supporting multi-stem cell interfollicular epidermal homeostasis models and suggest that transitional basal stem cells are stable states essential for proper stratification. Finally, alterations in differentially expressed transitional basal stem cell genes result in severe thinning of human skin equivalents, validating their essential role in epidermal homeostasis and reinforcing the critical nature of basal stem cell heterogeneity.


Assuntos
Diferenciação Celular , Células Epidérmicas/citologia , Homeostase , Células-Tronco/citologia , Comunicação Celular/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Prepúcio do Pênis/citologia , Prepúcio do Pênis/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Recém-Nascido , Queratinócitos/citologia , Queratinócitos/metabolismo , Masculino , Modelos Biológicos , Transdução de Sinais , Células-Tronco/metabolismo
5.
Gene ; 760: 145003, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739587

RESUMO

Imiquimod (IMQ) is approved as a first-line treatment for genital warts caused by human papillomavirus (HPV) infection. However, the recurrence rate is very high. HPV E7 protein plays a critical role in HPV immune escape. However, the role of HPV11 E7 protein in genital warts recurrence during IMQ treatment is not clear. Here, we found that the expression profile of NHEK cells was obviously changed after IMQ treatment, and a large number of genes encoding cytokines and genes involved in cytokine-mediated signaling pathways and cellular metabolic signaling pathways were up- or downregulated. HPV11E7 overexpression inhibited the IMQ-induced production of of multiple chemokines and colony-stimulating factors in NHEK cells. Furthermore, we found that HPV11E7 could impair the activation of mitogen-activated protein kinase (MAPK) signaling pathway. Therefore, our results suggested that HPV11 E7 diminishes the production of chemokines, colony-stimulating factors and other cytokines via inhibition of the MAPK signaling pathway, which suppresses the therapeutic effect of IMQ and promotes the recurrence of diseases, such as condyloma acuminatum.


Assuntos
Imiquimode/farmacologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Quimiocinas/biossíntese , Quimiocinas/genética , Quimiocinas/metabolismo , Fatores Estimuladores de Colônias/biossíntese , Fatores Estimuladores de Colônias/metabolismo , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Papillomavirus Humano 11/metabolismo , Humanos , Imiquimode/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Oncogênicas Virais/imunologia , Infecções por Papillomavirus/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
6.
PLoS One ; 15(8): e0237985, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822395

RESUMO

Allogeneic cultured epidermis (allo-CE) is a cultured keratinocyte sheet manufactured from donor cells and promotes wound healing when used in deep dermal burns, donor sites, and chronic ulcers and serves as a wound dressing. Allo-CE is usually cryopreserved to be ready to use. However, the cryopreservation procedure will damage the cell viability, and the influence of Allo-CE, according to its viability or wound healing process, has not been evaluated sufficiently. In this study, we aimed to prove the influence of keratinocyte viability contained in allo-CEs on wound healing. We prepared CEs with Green's method using keratinocytes obtained from a polydactyly patient and then prepared four kinds of CEs with different cell viabilities [fresh, cryopreserved, frozen, and FT (freeze and thaw)]. The cell viabilities of fresh, cryopreserved, frozen, and FT CEs were 95.7%, 59.9%, 16.7%, and 0.0%, respectively. The four CEs had homogeneous characteristics, except for small gaps found in the FT sheet by transmission electron microscopy observation. The four CEs were applied on the full-thickness skin defect of diabetic mice (BKS.Cg-Dock 7m +/+ Leprdb/Jcl), and the wound area and neoepithelium length were evaluated on days 4, 7, and 14. As a result, FT CEs without viable cells similarly promoted epithelialization on days 4 and 7 (p<0.05) and accelerated wound closure on day 7 (p<0.01) as fresh CEs compared with the control group. In conclusion, the promoting effect of allo-CE on wound healing does not depend on cell viability. Lyophilized CEs may be a suitable wound dressing with a long storage period at room temperature.


Assuntos
Diabetes Mellitus Experimental/patologia , Queratinócitos/transplante , Cicatrização , Animais , Sobrevivência Celular , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Humanos , Lactente , Queratinócitos/citologia , Queratinócitos/metabolismo , Masculino , Camundongos , Polidactilia/metabolismo , Polidactilia/patologia , Reepitelização
7.
Scand J Immunol ; 92(5): e12953, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32757303

RESUMO

Psoriasis is an inflammatory disease that arises in genetically predisposed individuals. Chronic skin lesions that contain activated immune cells can persist for years. Systemic inhibition of TNF, IL-17 and IL-23 cytokines has revolutionized psoriasis care during the recent decades. Unfortunately, local relapse of disease is common at previously inflamed sites after cessation of treatment. This highlights that fundamental pathologic alterations of the affected tissues are not completely resolved during clinical remission. Here, we present arguments for a local disease memory located in both dermis and epidermis in psoriasis skin. We decipher different cellular components and intercellular crosstalk that sustain local disease memory and amplify disease relapse in human psoriasis. Decrypting the mechanisms underlying the establishment and persistence of pathogenic memory cells in resolved psoriasis may provide new therapeutic perspectives aimed at long-term remission of psoriasis.


Assuntos
Cicatriz/imunologia , Citocinas/imunologia , Interleucina-17/imunologia , Queratinócitos/imunologia , Psoríase/imunologia , Pele/imunologia , Cicatriz/metabolismo , Citocinas/metabolismo , Epiderme/imunologia , Epiderme/metabolismo , Epiderme/patologia , Humanos , Memória Imunológica/imunologia , Interleucina-17/metabolismo , Queratinócitos/metabolismo , Queratinócitos/patologia , Psoríase/metabolismo , Recidiva , Pele/metabolismo , Pele/patologia
8.
J Oleo Sci ; 69(7): 719-726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32612021

RESUMO

Residues of olive fruit (ROF) after the extraction of oils are an increasing source of industrial waste, because olive oil is becoming more popular as a healthy food. It has been reported that olives have some polyphenols that have an antioxidation capability. On the other hand, excess oxidative stress disrupts epidermal barrier function. This study was conducted to determine whether ROF could be utilized as an antioxidant source to reduce industrial wastes and to identify possible active materials to maintain healthy skin. Olive fruits are categorized into two groups depending on the time of harvest, young fruit (YF) and mature fruit (MF). Thus, we examined the antioxidant potentials of extracts from YF and from MF to remove reactive oxygen species (ROS) from biological and chemical aspects. HaCaT keratinocytes cultured with extracts of YF or MF had reduced levels of intracellular ROS in spite of the relatively low chemical capability against ROS scavenging. The biological effects of the YF extract were superior to those of the MF extract. The YF extract showed effective reductions of intracellular ROS and carbonylated proteins that were elevated by the stress-related hormone cortisol. In addition, the YF extract reinforced the intracellular antioxidation capability through the activation of Nrf2 signaling. Taken together, the YF extract was an effective source to reinforce the intracellular antioxidation capability. We conclude from these results that utilizing ROF would lead to the reduction of industrial wastes and would supply active materials to maintain healthy skin.


Assuntos
Queratinócitos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Olea/química , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Antioxidantes , Células Cultivadas , Humanos , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
9.
Clin Interv Aging ; 15: 897-905, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606631

RESUMO

Introduction: Skin, as the outermost organ, is exposed to a wide range of environmental risk factors including ultraviolet (UV) and all kinds of pollutants. Excessive UV exposure contributes to many disorders, such as photoaging, skin inflammation, and carcinogenesis. Methods: To determine the effects of bamboo extract (BEX) from our local plant, Acidosasa longiligula, on UV-irritated human skin, we conducted a variety of studies, including Western blot, apoptosis assays, reactive oxygen species (ROS) detection, and thioredoxin (TXN) and thioredoxin reductase (TXNRD) activity assays in primary skin keratinocytes. Results: We first determined that BEX protects human skin keratinocytes against UV radiation-induced apoptosis and ROS production. UV radiation can robustly impair TXN and TXNRD activity which can, in turn, be significantly rescued by BEX treatment. Moreover, BEX regulates TXN1 levels in primary skin keratinocytes and TXN1 is proved to be required for the protective function of BEX. Last, we found that the NF-κB/p65 pathway mediates the protective function of BEX against UV. Discussion: Collectively, our work delineates the beneficial role of BEX in UV-induced skin cell damage and provides a novel therapeutic reagent to prevent or alleviate the progress of photoaging and other UV-provoked skin diseases.


Assuntos
Queratinócitos/metabolismo , Extratos Vegetais/farmacologia , Protetores contra Radiação/farmacologia , Pele/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Humanos , Poaceae , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta/efeitos adversos
11.
PLoS One ; 15(7): e0235295, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687504

RESUMO

Spontaneous mutations in the SHANK-associated RH domain interacting protein (Sharpin) resulted in a severe autoinflammatory type of chronic proliferative dermatitis, inflammation in other organs, and lymphoid organ defects. To determine whether cell-type restricted loss of Sharpin causes similar lesions, a conditional null mutant was created. Ubiquitously expressing cre-recombinase recapitulated the phenotype seen in spontaneous mutant mice. Limiting expression to keratinocytes (using a Krt14-cre) induced a chronic eosinophilic dermatitis, but no inflammation in other organs or lymphoid organ defects. The dermatitis was associated with a markedly increased concentration of serum IgE and IL18. Crosses with S100a4-cre resulted in milder skin lesions and moderate to severe arthritis. This conditional null mutant will enable more detailed studies on the role of SHARPIN in regulating NFkB and inflammation, while the Krt14-Sharpin-/- provides a new model to study atopic dermatitis.


Assuntos
Dermatite Atópica/genética , Inflamação/genética , Queratina-14/genética , Proteínas do Tecido Nervoso/genética , Proteína A4 de Ligação a Cálcio da Família S100/genética , Animais , Apoptose/genética , Artrite/genética , Artrite/patologia , Dermatite Atópica/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Humanos , Imunoglobulina E/genética , Inflamação/patologia , Integrases/genética , Interleucina-18/genética , Queratinócitos/metabolismo , Queratinócitos/patologia , Camundongos , NF-kappa B/genética , Fenótipo , Transdução de Sinais
12.
PLoS One ; 15(7): e0235515, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32692781

RESUMO

BACKGROUND: The skin provides a predominant barrier against chemical, physical and microbial incursion. The intemperate exposure to ultraviolet A (UVA) radiation can cause excessive cellular oxidative stress, leading to skin damage, proteins damage and mitochondrial dysfunction. There is sufficient evidences supporting the proposal that mitochondria is highly implicated in skin photo-damage. METHODS: In the present study, a polysaccharide isolated from Astragalus membranaceus was further purified to be an α-glucan, which was further investigated its beneficial influence on UVA-induced photo-damage in HaCaT cells. RESULTS: Our results showed that the purified Astragalus membranaceus polysaccharide (AP) can protect HaCaT cells from UVA-induced photo-damage through reducing UVA-induced intracellular ROS production and mitochondrial membrane potential, thereby altering ATP content. It was found that the UVA induced damage in HaCaT cells could be effectively restored by co-treatment with AP. CONCLUSIONS: AP exhibited promising potential for advanced application as multifunctional skin care products and drugs.


Assuntos
Astragalus propinquus/química , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Polissacarídeos/farmacologia , Protetores contra Radiação/farmacologia , Raios Ultravioleta/efeitos adversos , Trifosfato de Adenosina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/química , Protetores contra Radiação/química , Espécies Reativas de Oxigênio/metabolismo
13.
Food Chem ; 333: 127510, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32673958

RESUMO

Aqueous coenzyme Q10 (CoQ10) dispersions were prepared using sugary maize dendrimer-like glucan (SMDG) with solid-dispersion treatment. After measuring solubility, recovery rate and loading rate, the initial weight ratio of CoQ10:SMDG was optimized to be 1:27, with the solubility markedly increasing up 188.8-folds compared to pure CoQ10 solution. The structural characterizations of CoQ10-SMDG formulation showed crystal CoQ10 was entrapped in SMDG matrix for amorphous state, associated with the strong interactions with glucan chains. The antioxidant activity of CoQ10-SMDG was assessed via DPPH and FRAP assay. DPPH scavenging activity and FRAP value of it were as high as 95.1% and 0.87 mM, respectively. The cellular uptake of CoQ10 in CoQ10-SMDG group was significantly higher than that of natural CoQ10. CoQ10-SMDG also exhibited significant protective effects against cellular damage in H2O2-induced HaCaT cell model. The results indicated that dendrimer-like glucan is an excellent platform to encapsulate and improve biological activity of hydropholic compounds.


Assuntos
Antioxidantes/química , Glucanos/química , Nanopartículas/química , Ubiquinona/análogos & derivados , Antioxidantes/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dendrímeros/química , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/toxicidade , Queratinócitos/citologia , Queratinócitos/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Tamanho da Partícula , Solubilidade , Ubiquinona/química , Ubiquinona/metabolismo
14.
Proc Natl Acad Sci U S A ; 117(30): 17796-17807, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32651268

RESUMO

Fluctuation in signal transduction pathways is frequently observed during mammalian development. However, its role in regulating stem cells has not been explored. Here we tracked spatiotemporal ERK MAPK dynamics in human epidermal stem cells. While stem cells and differentiated cells were distinguished by high and low stable basal ERK activity, respectively, we also found cells with pulsatile ERK activity. Transitions from Basalhi-Pulselo (stem) to Basalhi-Pulsehi, Basalmid-Pulsehi, and Basallo-Pulselo (differentiated) cells occurred in expanding keratinocyte colonies and in response to differentiation stimuli. Pharmacological inhibition of ERK induced differentiation only when cells were in the Basalmid-Pulsehi state. Basal ERK activity and pulses were differentially regulated by DUSP10 and DUSP6, leading us to speculate that DUSP6-mediated ERK pulse down-regulation promotes initiation of differentiation, whereas DUSP10-mediated down-regulation of mean ERK activity promotes and stabilizes postcommitment differentiation. Levels of MAPK1/MAPK3 transcripts correlated with DUSP6 and DUSP10 transcripts in individual cells, suggesting that ERK activity is negatively regulated by transcriptional and posttranslational mechanisms. When cells were cultured on a topography that mimics the epidermal-dermal interface, spatial segregation of mean ERK activity and pulses was observed. In vivo imaging of mouse epidermis revealed a patterned distribution of basal cells with pulsatile ERK activity, and down-regulation was linked to the onset of differentiation. Our findings demonstrate that ERK MAPK signal fluctuations link kinase activity to stem cell dynamics.


Assuntos
Diferenciação Celular , Células Epidérmicas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células-Tronco/metabolismo , Animais , Técnicas de Cultura de Células , Proliferação de Células , Ativação Enzimática , Células Epidérmicas/citologia , Queratinócitos/metabolismo , Mamíferos , Camundongos , Fosfoproteínas Fosfatases/metabolismo , Transdução de Sinais , Células-Tronco/citologia
15.
Cell Immunol ; 354: 104147, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32593012

RESUMO

CARD14 is a scaffold molecule predominantly expressed in keratinocytes and genetic variants in the CARD14 gene confer an increased risk of inflammatory skin disease. Due to its association with common skin diseases psoriasis and atopic dermatitis, the biological function of CARD14 is of relevant interest to human health. CARD14 recruits BCL10 and MALT1 to form the CARD-BCL10-MALT1 complex, which modulates NF-κB and MAPK signalling pathways, yet little is known about how CARD14 is regulated or activated in the context of the innate immune response and in chronic inflammation. This review summarises the current understanding of the molecular function and regulatory mechanisms of CARD14 and highlights recent findings in human disease and murine mouse models.


Assuntos
Inflamação/imunologia , Queratinócitos/metabolismo , Pele/imunologia , Animais , Proteína 10 de Linfoma CCL de Células B/metabolismo , Proteínas Adaptadoras de Sinalização CARD , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Guanilato Quinases , Humanos , Imunidade Inata , Queratinócitos/patologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais
16.
Nat Commun ; 11(1): 2988, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532976

RESUMO

Tissue homeostasis requires regulation of cell-cell communication, which relies on signaling molecules and cell contacts. In skin epidermis, keratinocytes secrete factors transduced by melanocytes into signaling cues promoting their pigmentation and dendrite outgrowth, while melanocytes transfer melanin pigments to keratinocytes to convey skin photoprotection. How epidermal cells integrate these functions remains poorly characterized. Here, we show that caveolae are asymmetrically distributed in melanocytes and particularly abundant at the melanocyte-keratinocyte interface in epidermis. Caveolae in melanocytes are modulated by ultraviolet radiations and keratinocytes-released factors, like miRNAs. Preventing caveolae formation in melanocytes increases melanin pigment synthesis through upregulation of cAMP signaling and decreases cell protrusions, cell-cell contacts, pigment transfer and epidermis pigmentation. Altogether, we identify that caveolae serve as molecular hubs that couple signaling outputs from keratinocytes to mechanical plasticity of pigment cells. The coordination of intercellular communication and contacts by caveolae is thus crucial to skin pigmentation and tissue homeostasis.


Assuntos
Cavéolas/metabolismo , Queratinócitos/metabolismo , Melanócitos/metabolismo , Pigmentação da Pele/fisiologia , Pele/metabolismo , Caveolina 1/metabolismo , Comunicação Celular/fisiologia , Comunicação Celular/efeitos da radiação , Células Cultivadas , Técnicas de Cocultura , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Epiderme/ultraestrutura , Células HeLa , Humanos , Queratinócitos/citologia , Melanócitos/citologia , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos da radiação , Pele/citologia , Pele/ultraestrutura , Raios Ultravioleta
17.
Nat Commun ; 11(1): 2711, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483135

RESUMO

p16INK4a (CDKN2A) is a central tumor suppressor, which induces cell-cycle arrest and senescence. Cells expressing p16INK4a accumulate in aging tissues and appear in premalignant lesions, yet their physiologic effects are poorly understood. We found that prolonged expression of transgenic p16INK4a in the mouse epidermis induces hyperplasia and dysplasia, involving high proliferation rates of keratinocytes not expressing the transgene. Continuous p16INK4a expression increases the number of epidermal papillomas formed after carcinogen treatment. Wnt-pathway ligands and targets are activated upon prolonged p16INK4a expression, and Wnt inhibition suppresses p16INK4a-induced hyperplasia. Senolytic treatment reduces p16INK4a-expressing cell numbers, and inhibits Wnt activation and hyperplasia. In human actinic keratosis, a precursor of squamous cell carcinoma, p16INK4a-expressing cells are found adjacent to dividing cells, consistent with paracrine interaction. These findings reveal that chronic p16INK4a expression is sufficient to induce hyperplasia through Wnt-mediated paracrine stimulation, and suggest that this tumor suppressor can promote early premalignant epidermal lesion formation.


Assuntos
Transformação Celular Neoplásica/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Epiderme/metabolismo , Via de Sinalização Wnt/genética , Animais , Proliferação de Células/genética , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Humanos , Hiperplasia/genética , Hiperplasia/metabolismo , Queratinócitos/metabolismo , Ceratose/genética , Ceratose/metabolismo , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Papiloma/genética , Papiloma/metabolismo , Papiloma/patologia
18.
J Toxicol Sci ; 45(6): 327-337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32493875

RESUMO

Hydrolyzed wheat proteins (HWPs) contained in cosmetics have occasionally caused immediate-type hypersensitivity following repeated skin exposure. Although the Cosmetic Ingredient Review Expert Panel concluded that < 3,500 Da HWP is safe for use in cosmetics, it remains biologically unknown how allergenic HWPs evoke immediate-type allergy percutaneously. Keratinocyte-derived thymic stromal lymphopoietin (TSLP) induces type 2 immune responses, which play an essential role in the pathogenesis of immediate-type allergy. Previously, we demonstrated that protein allergens in cultured human keratinocytes strongly induced long-form TSLP (loTSLP) transcription. However loTSLP-regulating signaling by HWP is poorly understood. In this study, we performed global gene expression analysis by microarray to investigate how the allergenic HWP acts on epidermal keratinocytes and the induction of loTSLP. Compared to human serum albumin (HSA), allergenic HWP induced a distinct gene expression pattern and preferentially activated various inflammatory pathways (High Mobility Group Box 1, Interleukin [IL]-6, IL-8, and acute phase response signaling). We identified 85 genes as potential nuclear factor-kappa B (NF-κB) target genes in GP19S-treated cells, compared with 29 such genes in HSA-treated cells. In addition, HWP specifically altered IL-17 signaling pathways in which transcription factors, NF-κB and activator protein-1, were activated. NF-κB signaling may be an important factor for HWP-induced inflammatory loTSLP transcription via inhibition assay. In conclusion, allergenic HWP caused an easily sensitizable milieu of activated inflammatory pathways and induced NF-κB-dependent loTSLP transcription in keratinocytes.


Assuntos
Citocinas , Queratinócitos/imunologia , NF-kappa B/metabolismo , Proteínas de Plantas/efeitos adversos , Transdução de Sinais , Transcrição Genética , Células Cultivadas , Citocinas/genética , Citocinas/fisiologia , Expressão Gênica , Humanos , Hidrólise , Hipersensibilidade Imediata/etiologia , Hipersensibilidade Imediata/genética , Inflamação/etiologia , Inflamação/genética , Interleucina-17/metabolismo , Queratinócitos/metabolismo , Triticum
19.
J Virol ; 94(14)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32350070

RESUMO

The papillomavirus (PV) E2 protein is a critical regulator of viral transcription and genome replication. We previously reported that tyrosine (Y) 138 of HPV-31 E2 is phosphorylated by the fibroblast growth factor receptor 3 (FGFR3) kinase. In this study, we generated quasiviruses containing G418-selectable HPV-31 genomes with phosphodeficient phenylalanine mutant E2 Y138F and phosphomimetic glutamic acid mutant Y138E. We observed significantly fewer early viral transcripts immediately after infection with these Y138 mutant genomes even though E2 occupancy at the viral origin was equivalent to that of wild-type E2. Keratinocytes infected with Y138F quasiviruses formed stable colonies, and the genomes were maintained as episomes, while those infected with Y138E quasiviruses did not. We previously reported that the HPV-31 E2 Y138 mutation to glutamic acid did not bind to the Brd4 C-terminal motif (CTM). Here, we demonstrate that HPV-16 E2 Y138E bound to full-length Brd4 but not to the Brd4 CTM. We conclude that association of E2 with the Brd4 CTM is necessary for viral genome replication and suggest that this interaction can be regulated by phosphorylation of E2 Y138.IMPORTANCE Papillomavirus (PV) is a double-stranded DNA tumor virus infecting the cutaneous and mucosal epithelium. The PV E2 protein associates with a number of cellular factors to mediate replication of the HPV genome. Fibroblast growth factor receptor 3 (FGFR3) regulates HPV replication through phosphorylation of tyrosine 138 in the HPV E2 protein. Employing a quasivirus infection model and selection for G418 resistant genomes, we demonstrated that Y138 is a critical residue for Brd4 association and that inability to complex with Brd4 does not support episomal replication.


Assuntos
Papillomavirus Humano 31/metabolismo , Queratinócitos/metabolismo , Infecções por Papillomavirus/metabolismo , Plasmídeos/metabolismo , Proteínas do Envelope Viral/metabolismo , Substituição de Aminoácidos , Linhagem Celular , Humanos , Queratinócitos/patologia , Queratinócitos/virologia , Mutação de Sentido Incorreto , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , Fosforilação , Plasmídeos/genética , Tirosina , Proteínas do Envelope Viral/genética
20.
PLoS One ; 15(4): e0222969, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32352958

RESUMO

In inflammatory skin conditions, such as psoriasis, vascular enlargement is associated with endothelial cell proliferation, release of cytokines and adhesion molecule expression. Interleukin (IL)-17A is a pro-inflammatory cytokine mainly secreted by T helper-17 cells that is critically involved in psoriasis pathogenesis. IL-36α, IL-36ß and IL-36γ are also inflammatory cytokines up-regulated in psoriasis and induced by various stimuli, including IL-17A. In this study, we found that human keratinocytes are the main source of IL-36, in particular of IL-36γ. This cytokine was strongly induced by IL-17A and, together with IL-17A, efficiently activated human dermal microvascular endothelial cells (HDMECs), which expressed both IL-17 and IL-36 receptors. Both IL-36γ and IL-17A induced cell proliferation through specific molecular cascades involving ERK1/2 only or ERK1/2, STAT3 and NF-κB, respectively. We highlighted the intense IL-17A- and IL-36γ -dependent interplay between keratinocytes and HDMECs, likely active in the psoriatic lesions and leading to the establishment of a cytokine network responsible for the development and maintenance of the inflamed state. IL-17A or IL-36γ showed in HDMECs a synergic activity with TNF-α by potently inducing inflammatory cytokine/chemokine release and ICAM-1 expression. We also investigated the involvement of IL-36γ and VEGF-A, substantially reduced in lesional skin of psoriatic patients pharmacologically treated with the anti-IL-17A antibody Secukinumab. Importantly, keratinocyte-derived IL-36γ represented an additional pro-angiogenic mediator of IL-17A. We observed that keratinocyte-derived VEGF-A influenced proliferation but did not act on expression of adhesion molecules in HDMECs. On the other hand, inhibition of IL-36γ released by IL-17A-treated keratinocytes impaired either proliferation or ICAM-1 expression both in HDMECs and in an in vivo murine model of psoriasis. Taken together, our data demonstrated that IL-17A and IL-36γ are highly involved in endothelial cells/keratinocytes crosstalk in inflammatory skin conditions.


Assuntos
Comunicação Celular , Células Endoteliais/metabolismo , Interleucina-17/metabolismo , Interleucina-1/metabolismo , Queratinócitos/metabolismo , Psoríase/metabolismo , Células Cultivadas , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA