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1.
FASEB J ; 35(11): e21957, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34606641

RESUMO

The Wnt signaling antagonist, sclerostin, is a potent suppressor of bone acquisition that also mediates endocrine communication between bone and adipose. As a result, Sost-/- mice exhibit dramatic increases in bone formation but marked decreases in visceral and subcutaneous adipose that are secondary to alterations in lipid synthesis and utilization. While interrogating the mechanism by which sclerostin influences adipocyte metabolism, we observed paradoxical increases in the adipogenic potential and numbers of CD45- :Sca1+ :PDGFRα+ adipoprogenitors in the stromal vascular compartment of fat pads isolated from male Sost-/- mice. Lineage tracing studies indicated that sclerostin deficiency blocks the differentiation of PDGFRα+ adipoprogenitors to mature adipocytes in association with increased Wnt/ß-catenin signaling. Importantly, osteoblast/osteocyte-specific Sost gene deletion mirrors the accumulation of PDGFRα+ adipoprogenitors, reduction in fat mass, and improved glucose metabolism evident in Sost-/- mice. These data indicate that bone-derived sclerostin regulates multiple facets of adipocyte physiology ranging from progenitor cell commitment to anabolic metabolism.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adipócitos/metabolismo , Adipogenia/genética , Osso e Ossos/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Células-Tronco/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Células Cultivadas , Técnicas de Inativação de Genes/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoblastos/metabolismo , Osteócitos/metabolismo , Osteogênese/genética
2.
Nat Commun ; 12(1): 5530, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545083

RESUMO

Long-term complications such as radiation-induced second malignancies occur in a subset of patients following radiation-therapy, particularly relevant in pediatric patients due to the long follow-up period in case of survival. Radiation-induced gliomas (RIGs) have been reported in patients after treatment with cranial irradiation for various primary malignancies such as acute lymphoblastic leukemia (ALL) and medulloblastoma (MB). We perform comprehensive (epi-) genetic and expression profiling of RIGs arising after cranial irradiation for MB (n = 23) and ALL (n = 9). Our study reveals a unifying molecular signature for the majority of RIGs, with recurrent PDGFRA amplification and loss of CDKN2A/B and an absence of somatic hotspot mutations in genes encoding histone 3 variants or IDH1/2, uncovering diagnostic markers and potentially actionable targets.


Assuntos
Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Amplificação de Genes , Glioma/genética , Recidiva Local de Neoplasia/patologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Adolescente , Adulto , Criança , Deleção Cromossômica , Análise por Conglomerados , Metilação de DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Rearranjo Gênico/genética , Genoma Humano , Glioma/patologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Radiação , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transcrição Genética , Adulto Jovem
3.
Sci Rep ; 11(1): 16268, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381120

RESUMO

Volume accommodation occurs via a novel mechanism involving interstitial cells in detrusor muscles. The interstitial cells in the bladder are PDGFRα+, and they restrain the excitability of smooth muscle at low levels and prevents the development of transient contractions (TCs). A common clinical manifestation of spinal cord injury (SCI)-induced bladder dysfunction is detrusor overactivity (DO). Although a myogenic origin of DO after SCI has been suggested, a mechanism for development of SCI-induced DO has not been determined. In this study we hypothesized that SCI-induced DO is related to loss of function in the regulatory mechanism provided by PDGFRα+ cells. Our results showed that transcriptional expression of Pdgfra and Kcnn3 was decreased after SCI. Proteins encoded by these genes also decreased after SCI, and a reduction in PDGFRα+ cell density was also documented. Loss of PDGFRα+ cells was due to apoptosis. TCs in ex vivo bladders during filling increased dramatically after SCI, and this was related to the loss of regulation provided by SK channels, as we observed decreased sensitivity to apamin. These findings show that damage to the mechanism restraining muscle contraction during bladder filling that is provided by PDGFRα+ cells is causative in the development of DO after SCI.


Assuntos
Contração Muscular/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/fisiologia , Traumatismos da Medula Espinal/complicações , Bexiga Urinária Hiperativa/etiologia , Bexiga Urinária/metabolismo , Bexiga Urinária/fisiopatologia , Animais , Apamina/metabolismo , Apoptose , Expressão Gênica , Camundongos , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Canais de Potássio Ativados por Cálcio de Condutância Baixa/genética , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Traumatismos da Medula Espinal/genética , Bexiga Urinária/citologia , Bexiga Urinária/patologia , Bexiga Urinária Hiperativa/fisiopatologia
4.
Biomed Res Int ; 2021: 4982227, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285913

RESUMO

PDGFRα signaling is critically important in ocular development. Previous data on PDGFRα lacks an expression map with high spatial and temporal resolution and lineage information. In this study, we aim to present a detailed PDGFRα expression and lineage map from early embryogenesis to adulthood. PDGFRα-CreER; mT/mG reporter mice were analyzed. mEGFP-positive cells contributed to multiple ocular lineages in a spatiotemporally regulated manner. A dynamic PDGFRα expression was identified in corneal stromal cells, lens epithelial cells, lens fiber cells, and retinal astrocytes during the entire period of eye development, while PDGFRα expression in retinal astrocytes from E17.5 onwards and in Müller glial cells was identified within two weeks after birth. By revealing detailed characterization of gene expression and function, we present a comprehensive map of PDGFRα-expressing cells in the eye for a better understanding of PDGFRα signaling's role during eye development.


Assuntos
Linhagem da Célula , Olho/citologia , Olho/embriologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Animais Recém-Nascidos , Linhagem da Célula/genética , Córnea/citologia , Córnea/embriologia , Embrião de Mamíferos/citologia , Olho/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Retina/citologia
5.
Med Microbiol Immunol ; 210(4): 197-209, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34091753

RESUMO

Polymorphonuclear leukocytes (PMNs) are regarded as vehicles for the hematogenous dissemination of human cytomegalovirus (HCMV). In cell culture, this concept has been validated with cell-free laboratory strains but not yet with clinical HCMV isolates that grow strictly cell-associated. We, therefore, aimed to evaluate whether PMNs can also transmit such isolates from initially infected fibroblasts to other cell types, which might further clarify the role of PMNs in HCMV dissemination and provide a model to search for potential inhibitors. PMNs, which have been isolated from HCMV-seronegative individuals, were added for 3 h to fibroblasts infected with recent cell-associated HCMV isolates, then removed and transferred to various recipient cell cultures. The transfer efficiency in the recipient cultures was evaluated by immunofluorescence staining of viral immediate early antigens. Soluble derivatives of the cellular HCMV entry receptor PDGFRα were analyzed for their potential to interfere with this transfer. All of five tested HCMV isolates could be transferred to fibroblasts, endothelial and epithelial cells with transfer rates ranging from 2 to 9%, and the transferred viruses could spread focally in these recipient cells within 1 week. The PDGFRα-derived peptides IK40 and GT40 reduced transfer by 40 and 70% when added during the uptake step. However, when added during the transfer step, only IK40 was effective, inhibiting transmission by 20% on endothelial cells and 50-60% on epithelial cells and fibroblasts. These findings further corroborate the assumption of cell-associated HCMV dissemination by PMNs and demonstrate that it is possible to inhibit this transmission mode.


Assuntos
Infecções por Citomegalovirus/transmissão , Infecções por Citomegalovirus/virologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/fisiologia , Neutrófilos/virologia , Peptídeos/farmacologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Antígenos Virais/metabolismo , Antivirais/farmacologia , Linhagem Celular , Citomegalovirus/isolamento & purificação , Células Endoteliais/virologia , Células Epiteliais/virologia , Fibroblastos/virologia , Humanos , Peptídeos/química , Internalização do Vírus/efeitos dos fármacos
6.
Development ; 148(14)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34184034

RESUMO

Signaling through the platelet-derived growth factor receptor alpha (PDGFRα) is crucial for mammalian craniofacial development, although the mechanisms by which the activity of downstream intracellular effectors is regulated to mediate gene expression changes have not been defined. We find that the RNA-binding protein Srsf3 is phosphorylated at Akt consensus sites downstream of PI3K-mediated PDGFRα signaling in mouse palatal mesenchyme cells, leading to its nuclear translocation. We further demonstrate that ablation of Srsf3 in the mouse neural crest lineage leads to facial clefting due to defective cranial neural crest cell proliferation and survival. Finally, we show that Srsf3 regulates the alternative RNA splicing of transcripts encoding protein kinases in the mouse facial process mesenchyme to regulate PDGFRα-dependent intracellular signaling. Collectively, our findings reveal that alternative RNA splicing is an important mechanism of gene expression regulation downstream of PI3K/Akt-mediated PDGFRα signaling in the facial mesenchyme and identify Srsf3 as a critical regulator of craniofacial development.


Assuntos
Processamento Alternativo , Mesoderma/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fatores de Processamento de Serina-Arginina/metabolismo , Transdução de Sinais , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Ligantes , Masculino , Camundongos , Camundongos Knockout , Crista Neural/embriologia , Crista Neural/metabolismo , Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas de Ligação a RNA/metabolismo , Fatores de Processamento de Serina-Arginina/genética
7.
J Agric Food Chem ; 69(21): 5897-5906, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34027663

RESUMO

The activation of adipose tissue browning and thermogenesis provides a new strategy to counter obesity and associated metabolic diseases. Here, a natural flavonoid chrysin is used as the supplement of a high-fat diet (HFD). Dietary chrysin alleviates adiposity and insulin resistance in HFD-fed mice. Meanwhile, dietary chrysin elevates systemic energy expenditure and enhances the uncoupling protein-1 (UCP1) level in subcutaneous adipose tissue (SAT), which is accompanied by the increased thermogenic program, beige preadipocyte number, and angiogenesis in SAT. Dietary chrysin also induces the expression of SAT platelet-derived growth factor receptor α (PDGFRα), which commits adipose progenitor cells to differentiate into beige or white adipocytes in response to various environmental signals. Double immunofluorescent staining for UCP1 and PDGFRα reveals that chrysin elevates the number of UCP1+PDGFRα+ beige progenitors in SAT. Further, chrysin treatment reverses the effects of the specific PDGFRα inhibitor imatinib on browning differentiation of stromal vascular fraction cells from SAT. Finally, chrysin-induced adipocyte browning is correlated with the expressions of microRNAs as PDGFRα inhibitors or thermogenesis suppressors. In conclusion, dietary chrysin promotes subcutaneous adipocyte browning and systematic energy expenditure by regulating PDGFRα and microRNA expressions in HFD-fed mice.


Assuntos
MicroRNAs , Receptor alfa de Fator de Crescimento Derivado de Plaquetas , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético , Flavonoides/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Gordura Subcutânea/metabolismo , Termogênese , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
8.
Sci Rep ; 11(1): 7553, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824385

RESUMO

Platelet-derived growth factor receptor-α (PDGFRα)-positive interstitial cells (ICs) are widely distributed in various organs and may be involved in the motility of various tubular organs. We, for the first time, aimed to investigate the distribution, immunohistochemical characteristics, and ultrastructure of PDGFRα-positive ICs in murine vas deferens, using confocal laser scanning microscopy, transmission electron microscopy (TEM), and immuno-electron microscopy (immuno-EM). For immunofluorescence, we used antibodies against PDGFRα and other markers of ICs. PDGFRα-positive ICs were distributed widely in the lamina propria, smooth muscles, and serosal layers. Although most PDGFRα-positive ICs labeled CD34, they did not label CD34 in the subepithelial layers. Additionally, PDGFRα-positive ICs were in close proximity to each other, as also to the surrounding cells. TEM and immuno-EM findings revealed that PDGFRα-positive ICs established close physical interactions with adjacent ICs. Extracellular vesicles were also detected around the PDGFRα-positive ICs. Our morphological findings suggest that PDGFRα-positive ICs may have several subpopulations, which can play an important role in intercellular signaling via direct contact with the IC network and the extracellular vesicles in the murine vas deferens. Further investigation on PDGFRα-positive ICs in the vas deferens may lead to understanding the vas deferens mortility.


Assuntos
Células Intersticiais de Cajal/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Ducto Deferente/metabolismo , Animais , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal/métodos , Músculo Liso/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética
9.
Sci Rep ; 11(1): 8683, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883668

RESUMO

The maladaptive remodeling of vessel walls with neointima formation is a common feature of proliferative vascular diseases. It has been proposed that neointima formation is caused by the dedifferentiation of mature smooth muscle cells (SMCs). Recent evidence suggests that adventitial cells also participate in neointima formation; however, their cellular dynamics are not fully understood. In this study, we utilized a lineage tracing model of platelet-derived growth factor receptor alpha (PDGFRa) cells and examined cellular behavior during homeostasis and injury response. PDGFRa marked adventitial cells that were largely positive for Sca1 and a portion of medial SMCs, and both cell types were maintained for 2 years. Upon carotid artery ligation, PDGFRa-positive (+) cells were slowly recruited to the neointima and exhibited an immature SMC phenotype. In contrast, in a more severe wire denudation injury, PDGFRa+ cells were recruited to the neointima within 14 days and fully differentiated into SMCs. Under pressure overload induced by transverse aortic constriction, PDGFRa+ cells developed marked adventitial fibrosis. Taken together, our observations suggest that PDGFRa+ cells serve as a reservoir of adventitial cells and a subset of medial SMCs and underscore their context-dependent response to vascular injuries.


Assuntos
Vasos Sanguíneos/lesões , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Túnica Adventícia/metabolismo , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Vasos Sanguíneos/fisiologia , Proliferação de Células , Homeostase , Masculino , Camundongos , Camundongos Transgênicos , Neointima/metabolismo
10.
PLoS One ; 16(4): e0249729, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33822814

RESUMO

NG2 immunoreactive cells (NG2 cells) are found in the brain and peripheral tissues including the skin, intestinal tracts, and bladder. In a previous study, we observed the presence of NG2 cells in the stomach using bioluminescence imaging techniques in NG2-firefly luciferase (fLuc) transgenic (Tg) rats. Here, we aimed to identify and characterize NG2 cells in the adult rat stomach. Immunohistochemical studies showed that NG2 cells were mainly present in the lamina propria and most of the cells were gastric telocytes, co-expressing CD34, and platelet-derived growth factor receptor alpha (PDGFRα), with a small oval-shaped cell body and extremely long and thin cellular prolongations. In the rat stomach, NG2-expressing telocytes comprised two subpopulations: NG2+/CD34+/PDGFRα+ and NG2+/CD34+/PDGFRα-. Furthermore, we showed that the expression of NG2 gene in the aged rat stomach decreased relative to that of the young rat stomach and the decline of NG2 expression in aged rats was mainly observed in NG2+/CD34+/PDGFRα+ telocytes. These findings suggested age-related alterations in NG2+/CD34+/PDGFRα+ telocytes of rat stomach.


Assuntos
Antígenos/metabolismo , Mucosa Gástrica/metabolismo , Proteoglicanas/metabolismo , Estômago/fisiologia , Telócitos/metabolismo , Fatores Etários , Animais , Antígenos CD34/metabolismo , Membrana Mucosa/citologia , Membrana Mucosa/metabolismo , Ratos , Ratos Transgênicos , Ratos Wistar , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Estômago/citologia , Telócitos/citologia
11.
Curr Opin Oncol ; 33(4): 323-328, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33867479

RESUMO

PURPOSE OF REVIEW: The current article revisits the most recent advances that occurred in the field of gastrointestinal stromal tumor (GIST) therapeutics. RECENT FINDINGS: GIST is driven by the oncogenic activation of KIT or PDGFRA receptor tyrosine kinases, and agents targeting these receptors lead to substantial benefit throughout the entire course of the disease. Two new drugs were approved in 2020. On one hand, ripretinib obtained the regulatory approval for the treatment of GIST patients after progression to all standard treatments. On the other hand, avapritinib became the first agent ever displaying activity in GIST driven by the multiresistant PDGFRA D842V mutation. The addition of both drugs to GIST therapeutics constitutes a remarkable milestone, particularly considering that the last agent approved was back in 2012. Similarly, the recent identification of neurotrophic tyrosine receptor kinase (NTRK) fusions in a subset of KIT/PDGFRA wild-type GISTs led to an open window for tailored treatment using specific NTRK inhibitors. Finally, multiple efforts have been made toward the clinical implementation of circulating tumor DNA evaluation to guide clinical decisions in GIST. SUMMARY: GIST has been consolidated over the years as a paradigmatic model in personalized medicine for the successful development of novel therapeutic strategies through targeted inhibition of oncogenic drivers.


Assuntos
Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Naftiridinas/uso terapêutico , Pirazóis/uso terapêutico , Pirróis/uso terapêutico , Triazinas/uso terapêutico , Ureia/análogos & derivados , Antineoplásicos/uso terapêutico , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/metabolismo , Humanos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Ureia/uso terapêutico
12.
Nat Commun ; 12(1): 2265, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859199

RESUMO

Nerve-glia (NG2) glia or oligodendrocyte precursor cells (OPCs) are distributed throughout the gray and white matter and generate myelinating cells. OPCs in white matter proliferate more than those in gray matter in response to platelet-derived growth factor AA (PDGF AA), despite similar levels of its alpha receptor (PDGFRα) on their surface. Here we show that the type 1 integral membrane protein neuropilin-1 (Nrp1) is expressed not on OPCs but on amoeboid and activated microglia in white but not gray matter in an age- and activity-dependent manner. Microglia-specific deletion of Nrp1 compromised developmental OPC proliferation in white matter as well as OPC expansion and subsequent myelin repair after acute demyelination. Exogenous Nrp1 increased PDGF AA-induced OPC proliferation and PDGFRα phosphorylation on dissociated OPCs, most prominently in the presence of suboptimum concentrations of PDGF AA. These findings uncover a mechanism of regulating oligodendrocyte lineage cell density that involves trans-activation of PDGFRα on OPCs via Nrp1 expressed by adjacent microglia.


Assuntos
Doenças Desmielinizantes/patologia , Microglia/fisiologia , Neuropilina-1/metabolismo , Células Precursoras de Oligodendrócitos/fisiologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Remielinização , Animais , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Cerebelo/citologia , Cerebelo/crescimento & desenvolvimento , Corpo Caloso/citologia , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/crescimento & desenvolvimento , Corpo Caloso/patologia , Doenças Desmielinizantes/induzido quimicamente , Modelos Animais de Doenças , Feminino , Humanos , Lisofosfatidilcolinas/administração & dosagem , Lisofosfatidilcolinas/toxicidade , Masculino , Camundongos , Camundongos Transgênicos , Microglia/efeitos dos fármacos , Microglia/ultraestrutura , Microscopia Eletrônica de Transmissão , Modelos Animais , Bainha de Mielina/metabolismo , Neuropilina-1/genética , Oligodendroglia/fisiologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Cultura Primária de Células
13.
Oncogene ; 40(15): 2682-2696, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33707748

RESUMO

Focal amplification of epidermal growth factor receptor (EGFR) and its ligand-independent, constitutively active EGFRvIII mutant form are prominent oncogenic drivers in glioblastoma (GBM). The EGFRvIII gene rearrangement is considered to be an initiating event in the etiology of GBM, however, the mechanistic details of how EGFRvIII drives cellular transformation and tumor maintenance remain unclear. Here, we report that EGFRvIII demonstrates a reliance on PDGFRA co-stimulatory signaling during the tumorigenic process in a genetically engineered autochthonous GBM model. This dependency exposes liabilities that were leveraged using kinase inhibitors treatments in EGFRvIII-expressing GBM patient-derived xenografts (PDXs), where simultaneous pharmacological inhibition of EGFRvIII and PDGFRA kinase activities is necessary for anti-tumor efficacy. Our work establishes that EGFRvIII-positive tumors have unexplored vulnerabilities to targeted agents concomitant to the EGFR kinase inhibitor repertoire.


Assuntos
Neoplasias Encefálicas/metabolismo , Receptores ErbB/metabolismo , Glioblastoma/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Células HEK293 , Xenoenxertos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores
14.
Nature ; 593(7858): 275-281, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33789339

RESUMO

Crohn's disease is a chronic inflammatory intestinal disease that is frequently accompanied by aberrant healing and stricturing complications. Crosstalk between activated myeloid and stromal cells is critical in the pathogenicity of Crohn's disease1,2, and increases in intravasating monocytes are correlated with a lack of response to anti-TNF treatment3. The risk alleles with the highest effect on Crohn's disease are loss-of-function mutations in NOD24,5, which increase the risk of stricturing6. However, the mechanisms that underlie pathogenicity driven by NOD2 mutations and the pathways that might rescue a lack of response to anti-TNF treatment remain largely uncharacterized. Here we use direct ex vivo analyses of patients who carry risk alleles of NOD2 to show that loss of NOD2 leads to dysregulated homeostasis of activated fibroblasts and macrophages. CD14+ peripheral blood mononuclear cells from carriers of NOD2 risk alleles produce cells that express high levels of collagen, and elevation of conserved signatures is observed in nod2-deficient zebrafish models of intestinal injury. The enrichment of STAT3 regulation and gp130 ligands in activated fibroblasts and macrophages suggested that gp130 blockade might rescue the activated program in NOD2-deficient cells. We show that post-treatment induction of the STAT3 pathway is correlated with a lack of response to anti-TNF treatment in patients, and demonstrate in vivo in zebrafish the amelioration of the activated myeloid-stromal niche using the specific gp130 inhibitor bazedoxifene. Our results provide insights into NOD2-driven fibrosis in Crohn's disease, and suggest that gp130 blockade may benefit some patients with Crohn's disease-potentially as a complement to anti-TNF therapy.


Assuntos
Doença de Crohn/metabolismo , Receptor gp130 de Citocina/metabolismo , Células Mieloides/citologia , Proteína Adaptadora de Sinalização NOD2/metabolismo , Células Estromais/citologia , Alelos , Animais , Colágeno/metabolismo , Receptor gp130 de Citocina/antagonistas & inibidores , Modelos Animais de Doenças , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Ileíte/metabolismo , Indóis/farmacologia , Interleucina-11/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Células Mieloides/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Estromais/metabolismo , Proteínas WT1/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
15.
Neoplasia ; 23(4): 375-390, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33784590

RESUMO

The tumor microenvironment (TME) is an important mediator of breast cancer progression. Cancer-associated fibroblasts constitute a major component of the TME and may originate from tissue-associated fibroblasts or infiltrating mesenchymal stromal cells (MSCs). The mechanisms by which cancer cells activate fibroblasts and recruit MSCs to the TME are largely unknown, but likely include deposition of a pro-tumorigenic secretome. The secreted embryonic protein NODAL is clinically associated with breast cancer stage and promotes tumor growth, metastasis, and vascularization. Herein, we show that NODAL expression correlates with the presence of activated fibroblasts in human triple-negative breast cancers and that it directly induces Cancer-associated fibroblasts phenotypes. We further show that NODAL reprograms cancer cell secretomes by simultaneously altering levels of chemokines (e.g., CXCL1), cytokines (e.g., IL-6) and growth factors (e.g., PDGFRA), leading to alterations in MSC chemotaxis. We therefore demonstrate a hitherto unappreciated mechanism underlying the dynamic regulation of the TME.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Células-Tronco Mesenquimais/metabolismo , Proteína Nodal/genética , Proteína Nodal/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral/fisiologia , Actinas/metabolismo , Linhagem Celular Tumoral , Quimiocina CXCL1/metabolismo , Quimiotaxia/fisiologia , Feminino , Humanos , Interleucina-6/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/fisiologia , Neoplasias de Mama Triplo Negativas/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
J Cell Physiol ; 236(9): 6726-6741, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33611789

RESUMO

Thrombocytopenia is a common complication of human cytomegalovirus (HCMV) infection in immunocompromised hosts, which contributes to poor prognosis even in patients receiving antiviral treatment. Here, we investigated the megakaryo/thrombopoiesis process, including the involvement of the c-Mpl/IEX-1 pathway, after HCMV infection, identified receptors mediating the interaction between megakaryocytes (MKs) and HCMV, and explored novel therapeutic targets. Our data shows that HCMV directly infects megakaryocytes in patients with HCMV DNAemia and influences megakaryopoiesis via the c-Mpl/IEX-1 pathway throughout megakaryocyte maturation, apoptosis, and platelet generation in vivo and in vitro. After treatment with inhibitors of PDGFRα and αvß3, the HCMV infection rate in MKs was significantly reduced, suggesting that IMC-3G3 and anti-αvß3 are potential therapeutic alternatives for viral infection. In summary, our study proposes a possible mechanism and potential treatments for thrombocytopenia caused by HCMV infection and other viral diseases associated with abnormal hemostasis.


Assuntos
Citomegalovirus/fisiologia , Transplante de Células-Tronco Hematopoéticas , Integrina alfaVbeta3/metabolismo , Megacariócitos/virologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Trombopoetina/metabolismo , Transdução de Sinais , Trombopoese , Adolescente , Adulto , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Criança , Citomegalovirus/ultraestrutura , Infecções por Citomegalovirus/patologia , Regulação para Baixo , Feminino , Humanos , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Ploidias , Fatores de Risco , Receptor 2 Toll-Like/metabolismo , Transplante Homólogo , Adulto Jovem
18.
J Cell Physiol ; 236(9): 6630-6642, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33615467

RESUMO

Obesity is a major contributing factor to the pathogenesis of Type 2 diabetes. Multiple human genetics studies suggest that high activity of the low molecular weight protein tyrosine phosphatase (LMPTP) promotes metabolic syndrome in obesity. We reported that LMPTP is a critical promoter of insulin resistance in obesity by regulating liver insulin receptor signaling and that inhibition of LMPTP reverses obesity-associated diabetes in mice. Since LMPTP is expressed in adipose tissue but little is known about its function, here we examined the role of LMPTP in adipocyte biology. Using conditional knockout mice, we found that selective deletion of LMPTP in adipocytes impaired obesity-induced subcutaneous adipocyte hypertrophy. We assessed the role of LMPTP in adipogenesis in vitro, and found that LMPTP deletion or knockdown substantially impaired differentiation of primary preadipocytes and 3T3-L1 cells into adipocytes, respectively. Inhibition of LMPTP in 3T3-L1 preadipocytes also reduced adipogenesis and expression of proadipogenic transcription factors peroxisome proliferator activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha. Inhibition of LMPTP increased basal phosphorylation of platelet-derived growth factor receptor alpha (PDGFRα) on activation motif residue Y849 in 3T3-L1, resulting in increased activation of the mitogen-associated protein kinases p38 and c-Jun N-terminal kinase and increased PPARγ phosphorylation on inhibitory residue S82. Analysis of the metabolome of differentiating 3T3-L1 cells suggested that LMPTP inhibition decreased cell glucose utilization while enhancing mitochondrial respiration and nucleotide synthesis. In summary, we report a novel role for LMPTP as a key driver of adipocyte differentiation via control of PDGFRα signaling.


Assuntos
Adipócitos/metabolismo , Adipócitos/patologia , Adipogenia , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Gordura Subcutânea/patologia , Células 3T3-L1 , Adipogenia/genética , Animais , Diferenciação Celular/genética , Respiração Celular , Tamanho Celular , Transporte de Elétrons , Deleção de Genes , Regulação da Expressão Gênica , Glucose/metabolismo , Glicólise , Hipertrofia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Metaboloma , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Modelos Biológicos , PPAR gama/metabolismo , Fosforilação , Fosfosserina/metabolismo , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
Theranostics ; 11(7): 3244-3261, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33537085

RESUMO

Rationale: (Myo)fibroblasts are the ultimate effector cells responsible for the production of collagen within alveolar structures, a core phenomenon in the pathogenesis of idiopathic pulmonary fibrosis (IPF). Although (myo)fibroblast-targeted therapy holds great promise for suppressing the progression of IPF, its development is hindered by the limited drug delivery efficacy to (myo)fibroblasts and the vicious circle of (myo)fibroblast activation and evasion of apoptosis. Methods: Here, a dual small interfering RNA (siRNA)-loaded delivery system of polymeric micelles is developed to suppress the development of pulmonary fibrosis via a two-arm mechanism. The micelles are endowed with (myo)fibroblast-targeting ability by modifying the Fab' fragment of the anti-platelet-derived growth factor receptor-α (PDGFRα) antibody onto their surface. Two different sequences of siRNA targeting protein tyrosine phosphatase-N13 (PTPN13, a promoter of the resistance of (myo)fibroblasts to Fas-induced apoptosis) and NADPH oxidase-4 (NOX4, a key regulator for (myo)fibroblast differentiation and activation) are loaded into micelles to inhibit the formation of fibroblastic foci. Results: We demonstrate that Fab'-conjugated dual siRNA-micelles exhibit higher affinity to (myo)fibroblasts in fibrotic lung tissue. This Fab'-conjugated dual siRNA-micelle can achieve remarkable antifibrotic effects on the formation of fibroblastic foci by, on the one hand, suppressing (myo)fibroblast activation via siRNA-induced knockdown of NOX4 and, on the other hand, sensitizing (myo)fibroblasts to Fas-induced apoptosis by siRNA-mediated PTPN13 silencing. In addition, this (myo)fibroblast-targeting siRNA-loaded micelle did not induce significant damage to major organs, and no histopathological abnormities were observed in murine models. Conclusion: The (myo)fibroblast-targeting dual siRNA-loaded micelles offer a potential strategy with promising prospects in molecular-targeted fibrosis therapy.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Fibrose Pulmonar Idiopática/terapia , Terapia de Alvo Molecular/métodos , Miofibroblastos/metabolismo , NADPH Oxidase 4/genética , Proteína Tirosina Fosfatase não Receptora Tipo 13/genética , Animais , Bleomicina/administração & dosagem , Expressão Gênica , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Micelas , Miofibroblastos/patologia , NADPH Oxidase 4/antagonistas & inibidores , NADPH Oxidase 4/metabolismo , Cultura Primária de Células , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 13/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 13/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Resultado do Tratamento
20.
Cell Death Dis ; 12(2): 166, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558485

RESUMO

A leading cause of preterm birth is the exposure to systemic inflammation (maternal/fetal infection), which leads to neuroinflammation and white matter injury (WMI). A wide range of cytokines and chemokines are expressed and upregulated in oligodendrocytes (OLs) in response to inflammation and numerous reports show that OLs express several receptors for immune related molecules, which enable them to sense inflammation and to react. However, the role of OL immune response in WMI is unclear. Here, we focus our study on toll-like receptor-3 (TLR3) that is activated by double-strand RNA (dsRNA) and promotes neuroinflammation. Despite its importance, its expression and role in OLs remain unclear. We used an in vivo mouse model, which mimics inflammation-mediated WMI of preterm born infants consisting of intraperitoneal injection of IL-1ß from P1 to P5. In the IL-1ß-treated animals, we observed the upregulation of Tlr3, IL-1ß, IFN-ß, Ccl2, and Cxcl10 in both PDGFRα+ and O4+ sorted cells. This upregulation was higher in O4+ immature OLs (immOLs) as compared to PDGFRα+ OL precursor cells (OPCs), suggesting a different sensitivity to neuroinflammation. These observations were confirmed in OL primary cultures: cells treated with TLR3 agonist Poly(I:C) during differentiation showed a stronger upregulation of Ccl2 and Cxcl10 compared to cells treated during proliferation and led to decreased expression of myelin genes. Finally, OLs were able to modulate microglia phenotype and function depending on their maturation state as assessed by qPCR using validated markers for immunomodulatory, proinflammatory, and anti-inflammatory phenotypes and by phagocytosis and morphological analysis. These results show that during inflammation the response of OLs can play an autonomous role in blocking their own differentiation: in addition, the immune activation of OLs may play an important role in shaping the response of microglia during inflammation.


Assuntos
Diferenciação Celular , Proliferação de Células , Encefalite/metabolismo , Leucoencefalopatias/metabolismo , Oligodendroglia/metabolismo , Receptor 3 Toll-Like/metabolismo , Substância Branca/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite/genética , Encefalite/imunologia , Encefalite/patologia , Feminino , Mediadores da Inflamação/metabolismo , Leucoencefalopatias/genética , Leucoencefalopatias/imunologia , Leucoencefalopatias/patologia , Masculino , Camundongos , Microglia/imunologia , Microglia/metabolismo , Microglia/patologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/imunologia , Oligodendroglia/patologia , Poli I-C/farmacologia , Gravidez , Nascimento Prematuro , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Receptor 3 Toll-Like/agonistas , Substância Branca/efeitos dos fármacos , Substância Branca/imunologia , Substância Branca/patologia
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