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1.
Nature ; 574(7777): 249-253, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31578523

RESUMO

The integrity of the mammalian epidermis depends on a balance of proliferation and differentiation in the resident population of stem cells1. The kinase RIPK4 and the transcription factor IRF6 are mutated in severe developmental syndromes in humans, and mice lacking these genes display epidermal hyperproliferation and soft-tissue fusions that result in neonatal lethality2-5. Our understanding of how these genes control epidermal differentiation is incomplete. Here we show that the role of RIPK4 in mouse development requires its kinase activity; that RIPK4 and IRF6 expressed in the epidermis regulate the same biological processes; and that the phosphorylation of IRF6 at Ser413 and Ser424 primes IRF6 for activation. Using RNA sequencing (RNA-seq), histone chromatin immunoprecipitation followed by sequencing (ChIP-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) of skin in wild-type and IRF6-deficient mouse embryos, we define the transcriptional programs that are regulated by IRF6 during epidermal differentiation. IRF6 was enriched at bivalent promoters, and IRF6 deficiency caused defective expression of genes that are involved in the metabolism of lipids and the formation of tight junctions. Accordingly, the lipid composition of the stratum corneum of Irf6-/- skin was abnormal, culminating in a severe defect in the function of the epidermal barrier. Collectively, our results explain how RIPK4 and IRF6 function to ensure the integrity of the epidermis and provide mechanistic insights into why developmental syndromes that are characterized by orofacial, skin and genital abnormalities result when this axis goes awry.


Assuntos
Diferenciação Celular , Células Epidérmicas/citologia , Epiderme/fisiologia , Fatores Reguladores de Interferon/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Anormalidades Múltiplas/genética , Animais , Fenda Labial/genética , Fissura Palatina/genética , Cistos/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Células Epidérmicas/metabolismo , Epiderme/embriologia , Anormalidades do Olho/genética , Feminino , Dedos/anormalidades , Regulação da Expressão Gênica , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/genética , Joelho/anormalidades , Articulação do Joelho/anormalidades , Lábio/anormalidades , Metabolismo dos Lipídeos/genética , Deformidades Congênitas das Extremidades Inferiores/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Fosfosserina/metabolismo , Proteínas Serina-Treonina Quinases/genética , Sindactilia/genética , Anormalidades Urogenitais/genética
2.
Nat Commun ; 10(1): 4042, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492871

RESUMO

Tissue injury induces changes in cellular identity, but the underlying molecular mechanisms remain obscure. Here, we show that upon damage in a mouse model, epidermal cells at the wound edge convert to an embryonic-like state, altering particularly the cytoskeletal/extracellular matrix (ECM) components and differentiation program. We show that SOX11 and its closest relative SOX4 dictate embryonic epidermal state, regulating genes involved in epidermal development as well as cytoskeletal/ECM organization. Correspondingly, postnatal induction of SOX11 represses epidermal terminal differentiation while deficiency of Sox11 and Sox4 accelerates differentiation and dramatically impairs cell motility and re-epithelialization. Amongst the embryonic genes reactivated at the wound edge, we identify fascin actin-bundling protein 1 (FSCN1) as a critical direct target of SOX11 and SOX4 regulating cell migration. Our study identifies the reactivated embryonic gene program during wound repair and demonstrates that SOX11 and SOX4 play a central role in this process.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Transcrição SOXC/genética , Cicatrização/genética , Ferimentos e Lesões/genética , Animais , Diferenciação Celular/genética , Movimento Celular/genética , Citoesqueleto/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/metabolismo , Epiderme/embriologia , Epiderme/metabolismo , Matriz Extracelular , Camundongos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Fatores de Transcrição SOXC/metabolismo , Ferimentos e Lesões/embriologia
3.
Insect Biochem Mol Biol ; 112: 103206, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31425850

RESUMO

Wings are an indispensable structure in many insects for their foraging, courtship, escape from predators, and migration. Cuticular proteins are major components of the insect cuticle and wings, but there is limited information on how cuticular proteins may play an essential role in wing morphogenesis. We identified a wing-specific cuticular protein, LmACP7, which belongs to the RR-2 subfamily of CPR chitin-binding proteins in the migratory locust. LmACP7 was initially produced in epidermal cells and subsequently migrated to the exocuticle at the pre-ecdysial stage in adult wings. Depletion of LmACP7 transcripts by RNA interference markedly reduced its protein amounts, which consequently led to abnormal wing morphogenesis. The deformed wings were curved, wrinkled, and failed to fully expand. We further demonstrated that the deformation was caused by both severe damage of the endocuticle and death of the epidermal cells in the wings. Based on these data, we propose that LmACP7 not only serves as an essential structural protein in the wing but is also required for the integrity of wing epithelial cells. LmACP7 contributes to production of the wing endocuticle and to the morphogenesis of functional wings in the migratory locust.


Assuntos
Proteínas de Insetos/genética , Locusta migratoria/genética , Asas de Animais/crescimento & desenvolvimento , Animais , Quitina/metabolismo , Células Epidérmicas/metabolismo , Proteínas de Insetos/metabolismo , Locusta migratoria/crescimento & desenvolvimento , Metamorfose Biológica/genética , Morfogênese/genética , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Interferência de RNA , Asas de Animais/anormalidades
4.
Microbiol Immunol ; 63(9): 367-378, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31273816

RESUMO

Heat-killed Lactobacillus plantarum L-137 (HK L-137), an immunobiotic lactic acid bacterium, has been reported to enhance IFN-γ production through induction of IL-12. In this study, we investigated the effects of HK L-137 on skin moisturizing and production of hyaluronic acid (HA), an extracellular matrix associated with the retention of skin moisture. Oral administration of HK L-137 suppressed the loss of water content in the stratum corneum in hairless mice. Treatment of primary epidermal cells with HK L-137 increased HA production. Supernatant from immune cells stimulated by HK L-137, which contained proinflammatory cytokines such as IL-12, TNF-α, and IFN-γ, upregulated HA production and hyaluronan synthase 2 (HAS2) messenger RNA expression by BALB/3T3 fibroblasts via activation of transcription factor nuclear factor κB (NFκB). Although treatment of the supernatant with anti-TNF-α antibody (Ab) alone did not inhibit the HA production, combination of anti-TNF-α Ab with anti-IFN-γ Ab significantly inhibited the HA production. Thus, HK L-137-induced IFN-γ plays a critical role in upregulated HA production in collaboration with TNF-α. HK L-137 may be useful for improvement of skin functions such as moisture retention by inducing HA production.


Assuntos
Citocinas/metabolismo , Células Epidérmicas/metabolismo , Fibroblastos/metabolismo , Ácido Hialurônico/metabolismo , Lactobacillus plantarum/fisiologia , Animais , Células 3T3 BALB , Fator de Crescimento Epidérmico/metabolismo , Feminino , Hialuronan Sintases , Interferon gama/metabolismo , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/metabolismo , Pele , Baço , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos
5.
Cell Prolif ; 52(5): e12638, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152465

RESUMO

OBJECTIVES: Terminally differentiated stratified squamous epithelial cells play an important role in barrier protection of the skin. The integrity of epidermal cells is maintained by tight regulation of proliferation and differentiation. The aim of this study was to investigate the role of epigenetic regulator H3K4me3 and its demethylase Jarid1b in the control of epithelial cell differentiation. MATERIALS AND METHODS: RT-qPCR, Western blotting and IHC were used to detect mRNA and protein levels. We analysed cell proliferation by CCK8 assay and cell migration by wound healing assay. ChIP was used to measure H3K4me3 enrichment. A chamber graft model was established for epidermal development. RESULTS: Our studies showed that H3K4me3 was decreased during epidermal differentiation. The H3K4me3 demethylase Jarid1b positively controlled epidermal cell differentiation in vitro and in vivo. Mechanistically, we found that Jarid1b substantially increased the expression of mesenchymal-epithelial transition (MET)-related genes, among which Ovol1 positively regulated differentiation gene expression. In addition, Ovol1 expression was repressed by PI3K-AKT pathway inhibitors and overexpression (O/E) of the PI3K-AKT pathway suppressor Ship1. Knockdown (KD) of Ship1 activated downstream PI3K-AKT pathway and enhanced Ovol1 expression in HaCaT. Importantly, we found that Jarid1b negatively regulated Ship1 expression, but not that of Pten, by directly binding to its promoter to modulate H3K4me3 enrichment. CONCLUSION: Our results identify an essential role of Jarid1b in the regulation of the Ship1/AKT/Ovol1 pathway to promote epithelial cell differentiation.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas Nucleares/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Proteínas de Ligação a DNA/genética , Células Epidérmicas/citologia , Células Epidérmicas/metabolismo , Transição Epitelial-Mesenquimal , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Histona Desmetilases com o Domínio Jumonji/genética , Masculino , Camundongos , Camundongos Nus , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/antagonistas & inibidores , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Regiões Promotoras Genéticas , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transdução de Sinais , Fatores de Transcrição/genética
6.
Mol Carcinog ; 58(9): 1656-1669, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31237385

RESUMO

In this study, we evaluated the role of signal transducer and activator of transcription 1 (STAT1) in response to acute solar ultraviolet (SUV) radiation in mouse epidermis. Analysis of the epidermis from SUV-irradiated mice revealed rapid phosphorylation of STAT1 (pSTAT1) on both tyrosine (tyr701) and serine (ser727) residues and increased levels of IRF-1 while later timepoints showed increased levels of unphosphorylated STAT1 (uSTAT1). STAT1 activation led to upregulation of several proinflammatory chemokine mRNAs in epidermis including Cxcl9, Cxcl10, and Ccl2, as well as, the immune checkpoint inhibitor Pd-l1. In addition, mRNA and protein levels of cyclooxygenase-2 (Cox-2/COX2) were upregulated in epidermis following exposure to SUV. Mice with keratinocyte-specific STAT1 deletion did not exhibit increased IRF-1 or proinflammatory gene expression in epidermis. Furthermore, epidermal COX-2 induction after SUV exposure was significantly reduced in mice with keratinocyte-specific deletion of STAT1. Additionally, SUV irradiation rapidly upregulated interferon gamma (IFNγ) mRNA in the epidermis and that skin resident epidermal CD3 + T-cells were the source of IFNγ production. IFNγ receptor-deficient mice confirmed dependency of STAT1 activation, proinflammatory gene expression and COX-2 upregulation in the epidermis on paracrine IFNγ signaling. Furthermore, keratinocyte-specific STAT1-deficiency reduced proliferation and hyperplasia due to SUV irradiation and this was associated with decreased immune infiltration of mast cells in the dermis. Collectively, the current results demonstrate that exposure to SUV leads to upregulation of IFNγ and downstream pSTAT1/IRF-1/uSTAT1 signaling in the epidermis. Further study of this pathway could lead to identification of novel targets for the prevention of nonmelanoma skin cancer.


Assuntos
Fator Regulador 1 de Interferon/metabolismo , Interferon gama/metabolismo , Queratinócitos/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/fisiologia , Raios Ultravioleta/efeitos adversos , Animais , Complexo CD3/metabolismo , Ciclo-Oxigenase 2/metabolismo , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Expressão Gênica/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Mensageiro/metabolismo , Pele/metabolismo , Neoplasias Cutâneas/metabolismo , Linfócitos T/metabolismo , Regulação para Cima/fisiologia
7.
Chem Biol Interact ; 309: 108701, 2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31181187

RESUMO

Pelargonidin, a well-known natural anthocyanidin found in berries strawberries, blueberries, red radishes and other natural foods, has been found to possess health beneficial effects including anti-cancer effect. Herein, we investigated the effect of pelargonidin on cellular transformation in mouse skin epidermal JB6 (JB6 P+) cells induced by tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Pelargonidin treatment significantly decreased colony formation and suppressed cell viability of JB6 P+ cells. Pelargonidin also induced the anti-oxidant response element (ARE)-luciferase activation in HepG2-C8 cells overexpressing the ARE-luciferase reporter. Knockdown of nuclear factor E2-related factor 2 (Nrf2) in shNrf2 JB6 P+ cells enhanced TPA-induced colony formation and attenuated pelargonidin's blocking effect. Pelargonidin reduced the protein levels of genes encoding methyltransferases (DNMTs) and histone deacetylases (HDACs). Importantly, pelargonidin decreased the DNA methylation in the Nrf2 promoter region of JB6 P+ cells and increased Nrf2 downstream target genes expression, such as NAD(P)H/quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1), involved in cellular protection. In summary, our results showed that pelargonidin blocks TPA-induced cell transformation. The possible molecular mechanisms of its potential anti-cancer effects against neoplastic transformation may be attributed to its activation of Nrf2-ARE signaling pathway and its cytoprotective effect.


Assuntos
Antocianinas/farmacologia , Desmetilação do DNA/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Antocianinas/química , Elementos de Resposta Antioxidante/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA-Citosina Metilases/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/efeitos dos fármacos , Células Epidérmicas/metabolismo , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Histona Desacetilases/metabolismo , Humanos , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Regiões Promotoras Genéticas , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
8.
Nat Commun ; 10(1): 2550, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186410

RESUMO

The presence and absence of RNA modifications regulates RNA metabolism by modulating the binding of writer, reader, and eraser proteins. For 5-methylcytosine (m5C) however, it is largely unknown how it recruits or repels RNA-binding proteins. Here, we decipher the consequences of m5C deposition into the abundant non-coding vault RNA VTRNA1.1. Methylation of cytosine 69 in VTRNA1.1 occurs frequently in human cells, is exclusively mediated by NSUN2, and determines the processing of VTRNA1.1 into small-vault RNAs (svRNAs). We identify the serine/arginine rich splicing factor 2 (SRSF2) as a novel VTRNA1.1-binding protein that counteracts VTRNA1.1 processing by binding the non-methylated form with higher affinity. Both NSUN2 and SRSF2 orchestrate the production of distinct svRNAs. Finally, we discover a functional role of svRNAs in regulating the epidermal differentiation programme. Thus, our data reveal a direct role for m5C in the processing of VTRNA1.1 that involves SRSF2 and is crucial for efficient cellular differentiation.


Assuntos
5-Metilcitosina/metabolismo , Metilação de DNA , Células Epidérmicas/citologia , Metiltransferases/metabolismo , RNA/metabolismo , Partículas de Ribonucleoproteínas em Forma de Abóbada/genética , Diferenciação Celular , Linhagem Celular , Citosina/metabolismo , Células Epidérmicas/metabolismo , Células HEK293 , Células HeLa , Células-Tronco Embrionárias Humanas/citologia , Humanos , Metiltransferases/genética , RNA/genética , Partículas de Ribonucleoproteínas em Forma de Abóbada/metabolismo
9.
Forensic Sci Int Genet ; 42: 21-30, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31212206

RESUMO

Proteomic genotyping detects single amino acid polymorphisms to infer the genotype of corresponding non-synonymous SNPs. Like any DNA genotype, these inferences can be used to estimate random match probability. Fingermarks are a common source of biological evidence that is sample limited and a highly variable source of identifying DNA. Genetically variant peptides from fingermarks, that contain single amino acid polymorphisms, are an additional source of identifying genetic information. To discover these peptide biomarkers epidermal corneocytes from 9 subjects were isolated, processed, digested with trypsin and applied to mass spectrometry. The resulting proteomic and matching exome datasets were used to discover, characterize and validate 60 genetically variant peptides. An average of 28.8 ± 4.4 genetically variant peptides were detected from each subject resulting in a total of 264 SNP allele inferences with 260 true and 4 false positives, a false discovery rate of 1.5%. Random match probabilities were estimated using the genotype frequencies from the matching major populations in the 1000 Genomes Project. Estimates ranged up to a value of 1 in 1.7 × 108, with a median probability of 1 in 2.4 × 106. Furthermore, the proteomically-inferred genotypes are likely to be compatible with the STR-based random match probability estimates since the closest STR locus was 2.2 Mb from the nearest GVP-inferred SNP. This project represents a novel mode of genetic information that can be obtained from fingermarks and has the potential to complement other methods of human identification including analysis of ridge patterns or touch DNA.


Assuntos
Dermatoglifia , Células Epidérmicas/metabolismo , Genótipo , Peptídeos/genética , Proteoma/genética , Alelos , Cromatografia Líquida , Perfilação da Expressão Gênica/métodos , Humanos , Espectrometria de Massas , Peptídeos/metabolismo , Polimorfismo de Nucleotídeo Único , Proteoma/metabolismo , Proteômica
10.
Nat Commun ; 10(1): 2759, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227717

RESUMO

Langerhans cells (LC) are thought to be the only mononuclear phagocyte population in the epidermis where they detect pathogens. Here, we show that CD11c+ dendritic cells (DCs) are also present. These cells are transcriptionally similar to dermal cDC2 but are more efficient antigen-presenting cells. Compared to LCs, epidermal CD11c+ DCs are enriched in anogenital tissues where they preferentially interact with HIV, express the higher levels of HIV entry receptor CCR5, support the higher levels of HIV uptake and replication and are more efficient at transmitting the virus to CD4 T cells. Importantly, these findings are observed using both a lab-adapted and transmitted/founder strain of HIV. We also describe a CD33low cell population, which is transcriptionally similar to LCs but does not appear to function as antigen-presenting cells or acts as HIV target cells. Our findings reveal that epidermal DCs in anogenital tissues potentially play a key role in sexual transmission of HIV.


Assuntos
Células Dendríticas/virologia , Células Epidérmicas/virologia , Infecções por HIV/transmissão , HIV-1/imunologia , Apresentação do Antígeno/imunologia , Antígeno CD11c/metabolismo , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Epidérmicas/imunologia , Células Epidérmicas/metabolismo , Epiderme/imunologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Voluntários Saudáveis , Humanos , Masculino , Cultura Primária de Células , Receptores CCR5/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Linfócitos T/imunologia , Internalização do Vírus
11.
Acta Med Okayama ; 73(2): 135-146, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31015748

RESUMO

The basement membrane (BM) is composed of various extracellular molecules and regulates tissue regeneration and maintenance. Here, we demonstrate that collagen XVIII was spatiotemporally expressed in the BM during skin wound healing in a mouse excisional wound-splinting model. Re-epithelialization was detected at days 3 and 6 post-wounding. The ultrastructure of epidermal BM was discontinuous at day 3, whereas on day 6 a continuous BM was observed in the region proximal to the wound edge. Immunohistochemistry demonstrated that collagen XVIII was deposited in the BM zone beneath newly forming epidermis in day 3 and 6 wounds. Laminin-332, known to be the earliest BM component appearing in wounds, was colocalized with collagen XVIII in the epidermal BM zone at days 3 and 6. The deposition of α1(IV) collagen and nidogen-1 in the epidermal BM zone occurred later than that of collagen XVIII. We also observed the short isoform of collagen XVIII in the epidermal BM zone at day 3 post-wounding. Collectively, our results suggested that collagen XVIII plays a role in the formation of the dermal-epidermal junction during re-epithelialization, and that it is the short isoform that is involved in the early phase of re-epithelialization.


Assuntos
Membrana Basal/fisiologia , Colágeno Tipo XVIII/metabolismo , Células Epidérmicas/metabolismo , Cicatrização/fisiologia , Animais , Membrana Basal/ultraestrutura , Epiderme/patologia , Junções Intercelulares/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real/métodos
12.
Dev Growth Differ ; 61(4): 276-282, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30968390

RESUMO

Skin development is tightly temporally coordinated with its sensory innervation, which consists of the peripheral branches of the dorsal root ganglion (DRG) axons. Various studies suggest that the skin produces a long-range attractant for the sensory axons. However, the exact identity of the guidance cue(s) remains unclear. To reveal the detailed molecular mechanism that controls DRG axon guidance and targeting, manipulation of specific skin layers at specific time points are required. To test a variety of attractants that can be expressed in specific skin layers at specific timepoints, we combined in utero electroporation with the Tol2 transposon system to induce long-term transgene expression in the developing mouse skin, including in the highly proliferative epidermal stem cells (basal layer) and their descendants (spinous and granular layer cells). The plasmid solution was injected as close to the hindpaw plantar surface as possible. Immediately, electric pulses were passed through the embryo to transduce the plasmid DNA into hindpaw skin cells. Balancing outcome measurements including: embryo survival, transfection efficiency, and the efficiency of transgene integration into host cells, we found that IUE was best performed on E13.5, and using an electroporation voltage of 34V. After immunostaining embryonic and early postnatal skin tissue sections for keratinocyte and sensory axon markers, we observe the growth of axons into skin epidermal layers including areas expressing EGFP. Therefore, this method is useful for studying the interaction between axon growth and epidermal cell division/differentiation.


Assuntos
Epiderme/inervação , Epiderme/metabolismo , Neurônios/metabolismo , Pele/inervação , Pele/metabolismo , Transgenes/genética , Animais , Axônios/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/metabolismo , Epiderme/embriologia , Epiderme/crescimento & desenvolvimento , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Gravidez , Pele/embriologia , Pele/crescimento & desenvolvimento
13.
PLoS Genet ; 15(4): e1008058, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30933982

RESUMO

In the skin and gill epidermis of fish, ionocytes develop alongside keratinocytes and maintain body fluid ionic homeostasis that is essential for adaptation to environmental fluctuations. It is known that ionocyte progenitors in zebrafish embryos are specified from p63+ epidermal stem cells through a patterning process involving DeltaC (Dlc)-Notch-mediated lateral inhibition, which selects scattered dlc+ cells into the ionocyte progenitor fate. However, mechanisms by which the ionocyte progenitor population is modulated remain unclear. Krüppel-like factor 4 (Klf4) transcription factor was previously implicated in the terminal differentiation of mammalian skin epidermis and is known for its bifunctional regulation of cell proliferation in a tissue context-dependent manner. Here, we report novel roles for zebrafish Klf4 in the ventral ectoderm during embryonic skin development. We found that Klf4 was expressed in p63+ epidermal stem cells of the ventral ectoderm from 90% epiboly onward. Knockdown or knockout of klf4 expression reduced the proliferation rate of p63+ stem cells, resulting in decreased numbers of p63+ stem cells, dlc-p63+ keratinocyte progenitors and dlc+ p63+ ionocyte progenitor cells. These reductions subsequently led to diminished keratinocyte and ionocyte densities and resulted from upregulation of the well-known cell cycle regulators, p53 and cdkn1a/p21. Moreover, mutation analyses of the KLF motif in the dlc promoter, combined with VP16-klf4 or engrailed-klf4 mRNA overexpression analyses, showed that Klf4 can bind the dlc promoter and modulate lateral inhibition by directly repressing dlc expression. This idea was further supported by observing the lateral inhibition outcomes in klf4-overexpressing or knockdown embryos. Overall, our experiments delineate novel roles for zebrafish Klf4 in regulating the ionocyte progenitor population throughout early stem cell stage to initiation of terminal differentiation, which is dependent on Dlc-Notch-mediated lateral inhibition.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células Epidérmicas/citologia , Células Epidérmicas/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Padronização Corporal , Diferenciação Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ectoderma/citologia , Ectoderma/embriologia , Ectoderma/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Brânquias/citologia , Brânquias/embriologia , Brânquias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transporte de Íons , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Receptores Notch/genética , Receptores Notch/metabolismo , Transativadores/genética , Transativadores/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
14.
Immunity ; 50(3): 655-667.e4, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893588

RESUMO

Restoration of barrier-tissue integrity after injury is dependent on the function of immune cells and stem cells (SCs) residing in the tissue. In response to skin injury, hair-follicle stem cells (HFSCs), normally poised for hair generation, are recruited to the site of injury and differentiate into cells that repair damaged epithelium. We used a SC fate-mapping approach to examine the contribution of regulatory T (Treg) cells to epidermal-barrier repair after injury. Depletion of Treg cells impaired skin-barrier regeneration and was associated with a Th17 inflammatory response and failed HFSC differentiation. In this setting, damaged epithelial cells preferentially expressed the neutrophil chemoattractant CXCL5, and blockade of CXCL5 or neutrophil depletion restored barrier function and SC differentiation after epidermal injury. Thus, Treg-cell regulation of localized inflammation enables HFSC differentiation and, thereby, skin-barrier regeneration, with implications for the maintenance and repair of other barrier tissues.


Assuntos
Diferenciação Celular/fisiologia , Quimiocina CXCL5/metabolismo , Epiderme/metabolismo , Folículo Piloso/metabolismo , Interleucina-17/metabolismo , Regeneração/fisiologia , Linfócitos T Reguladores/metabolismo , Animais , Células Epidérmicas/metabolismo , Células Epiteliais/metabolismo , Cabelo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco/metabolismo
16.
Med Sci (Paris) ; 35(2): 187-190, 2019 Feb.
Artigo em Francês | MEDLINE | ID: mdl-30774090

RESUMO

Careful sequencing studies on small samples of normal oesophageal epithelium reveal the presence of very abundant cellular clones harbouring mutations in known cancer genes (and elsewhere). The number and size of these clones increases with age. This surprising finding confirms previous studies on sun-exposed epidermis. It has important implications for the understanding of cancer initiation and will hopefully lead to conceptual and clinical advances.


Assuntos
Células Clonais/patologia , Epitélio/patologia , Células-Tronco Neoplásicas/patologia , Lesões Pré-Cancerosas/patologia , Nicho de Células-Tronco , Envelhecimento/patologia , Células Clonais/metabolismo , Células Epidérmicas/metabolismo , Células Epidérmicas/patologia , Humanos , Mutação/fisiologia , Lesões Pré-Cancerosas/genética , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Nicho de Células-Tronco/genética , Luz Solar/efeitos adversos
18.
Int J Mol Sci ; 20(3)2019 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30691106

RESUMO

Pollution-induced skin damage results in oxidative stress; cellular toxicity; inflammation; and, ultimately, premature skin aging. Previous studies suggest that the activation of autophagy can protect oxidation-induced cellular damage and aging-like changes in skin. In order to develop new anti-pollution ingredients, this study screened various kinds of natural extracts to measure their autophagy activation efficacy in cultured dermal fibroblast. The stimulation of autophagy flux by the selected extracts was further confirmed both by the expression of proteins associated with the autophagy signals and by electron microscope. Crepidiastrum denticulatum (CD) extract treated cells showed the highest autophagic vacuole formation in the non-cytotoxic range. The phosphorylation of adenosine monophosphate kinase (AMPK), but not the inhibition of mammalian target of rapamycin (mTOR), was observed by CD-extract treatment. Its anti-pollution effects were further evaluated with model compounds, benzo[a]pyrene (BaP) and cadmium chloride (CdCl2), and a CD extract treatment resulted in both the protection of cytotoxicity and a reduction of proinflammatory cytokines. These results suggest that the autophagy activators can be a new protection regimen for anti-pollution. Therefore, CD extract can be used for anti-inflammatory and anti-pollution cosmetic ingredients.


Assuntos
Asteraceae/química , Poluentes Ambientais/efeitos adversos , Células Epidérmicas/citologia , Extratos Vegetais/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Benzopirenos/efeitos adversos , Cloreto de Cádmio/efeitos adversos , Células Cultivadas , Citocinas/metabolismo , Células Epidérmicas/efeitos dos fármacos , Células Epidérmicas/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Extratos Vegetais/química , Serina-Treonina Quinases TOR/metabolismo
19.
Int J Mol Med ; 43(3): 1522-1530, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30628660

RESUMO

Gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, has been frequently used in targeted therapy for lung cancer. However, the widespread use of gefitinib in targeted therapy for patients with lung cancer is hampered by its common skin toxicities. The present study aimed to investigate the mechanisms underlying the skin toxicities of gefitinib. Normal human epidermal keratinocytes (NHEKs) treated with gefitinib were used for a series of in vitro assays, including MTT, reverse transcription­quantitative polymerase chain reaction, western blot analysis, immunohistochemistry and transepithelial electrical resistance and paracellular permeability detection. In the present study, it was determined that the skin toxicities of gefitinib may be due to claudin (CLDN)1 and CLDN4 downregulation and CLDN2 upregulation in NHEKs. Additionally, Src and signal transducer and activator of transcription 3 pathways were involved in gefitinib­induced barrier function disruption in NHEKs. In conclusion, the present study may provide novel insights for improving skin toxicity of gefitinib in patients with lung cancer.


Assuntos
Claudinas/genética , Células Epidérmicas/efeitos dos fármacos , Células Epidérmicas/metabolismo , Receptores ErbB/antagonistas & inibidores , Gefitinibe/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos
20.
Biomed Pharmacother ; 110: 248-253, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30508736

RESUMO

Skin provides the protective barrier for our body and undergoes the continuous regeneration in order to overcome damage from exposure to harmful environments and wounds. Epidermal stem cells (ESCs) play critical roles in skin regeneration. Humanin analogue, S14G-humanin (HNG), a prominent member of a newly discovered family of mitochondrial-derived peptides, has been shown to be a cytoprotective derivative in multiple cell types. In this study, we isolated mouse epidermal stem cells and investigated the cytoprotective effects of HNG on ESCs upon ultraviolet (UV)-B treatment. We show that HNG suppresses UV-B-induced ROS production and increases antioxidant glutathione expression. HNG-pretreated cells exhibit very mild production of cytokines, including TNF-α, IL-1ß, and IL-6, upon exposure to UV-B. HNG pretreatment is protective against UV-B-mediated cytotoxicity and promotes ESC survival. Moreover, HNG treatment attenuates the UV-B-induced reduction in mitochondrial membrane potential (MMP) and preserves their identity and stem cell capacity. Mechanistically, HNG treatment ameliorates the UV-B-induced reduction in Wnt/ß-catenin pathway proteins, including Wtn3a, Myc, and cyclin D1. Collectively, our data suggest that HNG acts as a pro-survival and anti-oxidative stress agent in ESCs and has the potential to be used in ESC-mediated therapies.


Assuntos
Citoproteção/efeitos dos fármacos , Células Epidérmicas/efeitos dos fármacos , Peptídeos/farmacologia , Células-Tronco/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Citoproteção/fisiologia , Relação Dose-Resposta a Droga , Células Epidérmicas/metabolismo , Células Epidérmicas/efeitos da radiação , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco/metabolismo , Células-Tronco/efeitos da radiação
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