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1.
PLoS One ; 15(7): e0234792, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614850

RESUMO

The Myo/Nog cell lineage was discovered in the chick embryo and is also present in adult mammalian tissues. The cells are named for their expression of mRNA for the skeletal muscle specific transcription factor MyoD and bone morphogenetic protein inhibitor Noggin. A third marker for Myo/Nog cells is the cell surface molecule recognized by the G8 monoclonal antibody (mAb). G8 has been used to detect, track, isolate and kill Myo/Nog cells. In this study, we screened a membrane proteome array for the target of the G8 mAb. The array consisted of >5,000 molecules, each synthesized in their native confirmation with appropriate post-translational modifications in a single clone of HEK-293T cells. G8 mAb binding to the clone expressing brain-specific angiogenesis inhibitor 1 (BAI1) was detected by flow cytometry, re-verified by sequencing and validated by transfection with the plasmid construct for BAI1. Further validation of the G8 target was provided by enzyme-linked immunosorbent assay. The G8 epitope was identified by screening a high-throughput, site directed mutagenesis library designed to cover 95-100% of the 954 amino acids of the extracellular domain of the BAI1 protein. The G8 mAb binds within the third thrombospondin repeat of the extracellular domain of human BAI1. Immunofluorescence localization experiments revealed that G8 and a commercially available BAI1 mAb co-localize to the subpopulation of Myo/Nog cells in the skin, eyes and brain. Expression of the multi-functional BAI1 protein in Myo/Nog cells introduces new possibilities for the roles of Myo/Nog cells in normal and diseased tissues.


Assuntos
Proteínas Angiogênicas/biossíntese , Miofibroblastos/metabolismo , Receptores Acoplados a Proteínas-G/biossíntese , Substituição de Aminoácidos , Proteínas Angiogênicas/química , Proteínas Angiogênicas/genética , Proteínas Angiogênicas/imunologia , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Encéfalo/citologia , Proteínas de Transporte/análise , Linhagem da Célula , Epitopos/imunologia , Proteínas do Olho/biossíntese , Proteínas do Olho/química , Proteínas do Olho/genética , Proteínas do Olho/imunologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Desenvolvimento Muscular , Proteína MyoD/análise , Especificidade de Órgãos , Conformação Proteica , Domínios Proteicos , Coelhos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas-G/química , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/imunologia , Sequências Repetitivas de Aminoácidos , Pele/citologia , Especificidade da Espécie , Tatuagem , Adulto Jovem
2.
PLoS One ; 15(7): e0235553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614927

RESUMO

Aortic aneurysm refers to dilatation of the aorta due to loss of elasticity and degenerative weakening of its wall. A preventive role for osteoprotegerin (Opg) in the development of abdominal aortic aneurysm has been reported in the CaCl2-induced aneurysm model, whereas Opg was found to promote suprarenal aortic aneurysm in the AngII-induced ApoE knockout mouse aneurysm model. To determine whether there is a common underlying mechanism to explain the impact of Opg deficiency on the vascular structure of the two aneurysm models, we analyzed suprarenal aortic tissue of 6-month-old ApoE-/-Opg-/- mice after AngII infusion for 28 days. Less aortic dissection and aortic lumen dilatation, more adventitial thickening, and higher expression of collagen I and Trail were observed in ApoE-/-Opg-/- mice relative to ApoE-/-Opg+/+ mice. An accumulation of α-smooth muscle actin and vimentin double-positive myofibroblasts was noted in the thickened adventitia of ApoE-/-Opg-/- mice. Our results suggest that fibrotic remodeling of the aorta induced by myofibroblast accumulation might be an important pathological event which tends to limit AngII-induced aortic dilatation in ApoE -/-Opg-/- mice.


Assuntos
Túnica Adventícia/patologia , Aneurisma da Aorta Abdominal/patologia , Osteoprotegerina/genética , Túnica Adventícia/fisiologia , Angiotensina II/farmacologia , Animais , Aorta Abdominal/patologia , Aorta Abdominal/fisiologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Colesterol/sangue , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Fibrose , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Osteoprotegerina/deficiência , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Regulação para Cima/efeitos dos fármacos
3.
PLoS One ; 15(7): e0232564, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726309

RESUMO

BACKGROUND: The identity and spatial distribution of prostatic cell types has been determined in humans but not in dogs, even though aging- and prostate-related voiding disorders are common in both species and mechanistic factors, such as prostatic collagen accumulation, appear to be shared between species. In this publication we characterize the regional distribution of prostatic cell types in the young intact dog to enable comparisons with human and mice and we examine how the cellular source of procollagen 1A1 changes with age in intact male dogs. METHODS: A multichotomous decision tree involving sequential immunohistochemical stains was validated for use in dog and used to identify specific prostatic cell types and determine their distribution in the capsule, peripheral, periurethral and urethral regions of the young intact canine prostate. Prostatic cells identified using this technique include perivascular smooth muscle cells, pericytes, endothelial cells, luminal, intermediate, and basal epithelial cells, neuroendocrine cells, myofibroblasts, fibroblasts, fibrocytes, and other hematolymphoid cells. To enhance rigor and transparency, all high resolution images (representative images shown in the figures and biological replicates) are available through the GUDMAP database at https://doi.org/10.25548/16-WMM4. RESULTS: The prostatic peripheral region harbors the largest proportion of epithelial cells. Aging does not change the density of hematolymphoid cells, fibroblasts, and myofibroblasts in the peripheral region or in the fibromuscular capsule, regions where we previously observed aging- and androgen-mediated increases in prostatic collagen abundance Instead, we observed aging-related changes the procollagen 1A1 positive prostatic cell identity from a myofibroblast to a fibroblast. CONCLUSIONS: Hematolymphoid cells and myofibroblasts are often identified as sources of collagen in tissues prone to aging-related fibrosis. We show that these are not the likely sources of pathological collagen synthesis in older intact male dogs. Instead, we identify an aging-related shift in the prostatic cell type producing procollagen 1A1 that will help direct development of cell type and prostate appropriate therapeutics for collagen accumulation.


Assuntos
Envelhecimento/fisiologia , Fibroblastos/metabolismo , Miofibroblastos/metabolismo , Pró-Colágeno/biossíntese , Próstata/citologia , Bexiga Urinária/fisiopatologia , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Suscetibilidade a Doenças , Cães , Imuno-Histoquímica , Masculino , Próstata/metabolismo , Próstata/patologia
4.
Nat Commun ; 11(1): 2768, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488016

RESUMO

Fibrotic disorders are some of the most devastating and poorly treated conditions in developed nations, yet effective therapeutics are not identified for many of them. A major barrier for the identification of targets and successful clinical translation is a limited understanding of the human fibrotic microenvironment. Here, we construct a stromal cell atlas of human fibrosis at single cell resolution from patients with Dupuytren's disease, a localized fibrotic condition of the hand. A molecular taxonomy of the fibrotic milieu characterises functionally distinct stromal cell types and states, including a subset of immune regulatory ICAM1+ fibroblasts. In developing fibrosis, myofibroblasts exist along an activation continuum of phenotypically distinct populations. We also show that the tetraspanin CD82 regulates cell cycle progression and can be used as a cell surface marker of myofibroblasts. These findings have important implications for targeting core pathogenic drivers of human fibrosis.


Assuntos
Contratura de Dupuytren/imunologia , Contratura de Dupuytren/metabolismo , Fibrose/imunologia , Fibrose/metabolismo , Células Estromais/metabolismo , Actinas/metabolismo , Biomarcadores/metabolismo , Quimiocinas CXC/metabolismo , Contratura de Dupuytren/patologia , Fibrose/patologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Medicina Molecular , Miofibroblastos/metabolismo , Tetraspaninas/metabolismo , Microambiente Tumoral/fisiologia
5.
Proc Natl Acad Sci U S A ; 117(23): 12856-12867, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32439707

RESUMO

The conventional outflow pathway is a complex tissue responsible for maintaining intraocular pressure (IOP) homeostasis. The coordinated effort of multiple cells with differing responsibilities ensures healthy outflow function and IOP maintenance. Dysfunction of one or more resident cell types results in ocular hypertension and risk for glaucoma, a leading cause of blindness. In this study, single-cell RNA sequencing was performed to generate a comprehensive cell atlas of human conventional outflow tissues. We obtained expression profiles of 17,757 genes from 8,758 cells from eight eyes of human donors representing the outflow cell transcriptome. Upon clustering analysis, 12 distinct cell types were identified, and region-specific expression of candidate genes was mapped in human tissues. Significantly, we identified two distinct expression patterns (myofibroblast- and fibroblast-like) from cells located in the trabecular meshwork (TM), the primary structural component of the conventional outflow pathway. We also located Schwann cell and macrophage signatures in the TM. The second primary component structure, Schlemm's canal, displayed a unique combination of lymphatic/blood vascular gene expression. Other expression clusters corresponded to cells from neighboring tissues, predominantly in the ciliary muscle/scleral spur, which together correspond to the uveoscleral outflow pathway. Importantly, the utility of our atlas was demonstrated by mapping glaucoma-relevant genes to outflow cell clusters. Our study provides a comprehensive molecular and cellular classification of conventional and unconventional outflow pathway structures responsible for IOP homeostasis.


Assuntos
Humor Aquoso/metabolismo , Glaucoma/patologia , Pressão Intraocular/fisiologia , Miofibroblastos/metabolismo , Malha Trabecular/metabolismo , Glaucoma/genética , Humanos , Macrófagos/metabolismo , RNA-Seq , Células de Schwann/metabolismo , Análise de Célula Única , Malha Trabecular/citologia
6.
Proc Natl Acad Sci U S A ; 117(20): 10832-10838, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32358190

RESUMO

While the concept of intercellular mechanical communication has been revealed, the mechanistic insights have been poorly evidenced in the context of myofibroblast-fibroblast interaction during fibrosis expansion. Here we report and systematically investigate the mechanical force-mediated myofibroblast-fibroblast cross talk via the fibrous matrix, which we termed paratensile signaling. Paratensile signaling enables instantaneous and long-range mechanotransduction via collagen fibers (less than 1 s over 70 µm) to activate a single fibroblast, which is intracellularly mediated by DDR2 and integrin signaling pathways in a calcium-dependent manner through the mechanosensitive Piezo1 ion channel. By correlating in vitro fibroblast foci growth models with mathematical modeling, we demonstrate that the single-cell-level spatiotemporal feature of paratensile signaling can be applied to elucidate the tissue-level fibrosis expansion and that blocking paratensile signaling can effectively attenuate the fibroblast to myofibroblast transition at the border of fibrotic and normal tissue. Our comprehensive investigation of paratensile signaling in fibrosis expansion broadens the understanding of cellular dynamics during fibrogenesis and inspires antifibrotic intervention strategies targeting paratensile signaling.


Assuntos
Fibroblastos/metabolismo , Fibrose/metabolismo , Miofibroblastos/metabolismo , Transdução de Sinais/fisiologia , Animais , Receptor com Domínio Discoidina 2/metabolismo , Humanos , Integrinas , Canais Iônicos/metabolismo , Mecanotransdução Celular
7.
Proc Natl Acad Sci U S A ; 117(21): 11387-11398, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32385149

RESUMO

Altered microarchitecture of collagen type I is a hallmark of wound healing and cancer that is commonly attributed to myofibroblasts. However, it remains unknown which effect collagen microarchitecture has on myofibroblast differentiation. Here, we combined experimental and computational approaches to investigate the hypothesis that the microarchitecture of fibrillar collagen networks mechanically regulates myofibroblast differentiation of adipose stromal cells (ASCs) independent of bulk stiffness. Collagen gels with controlled fiber thickness and pore size were microfabricated by adjusting the gelation temperature while keeping their concentration constant. Rheological characterization and simulation data indicated that networks with thicker fibers and larger pores exhibited increased strain-stiffening relative to networks with thinner fibers and smaller pores. Accordingly, ASCs cultured in scaffolds with thicker fibers were more contractile, expressed myofibroblast markers, and deposited more extended fibronectin fibers. Consistent with elevated myofibroblast differentiation, ASCs in scaffolds with thicker fibers exhibited a more proangiogenic phenotype that promoted endothelial sprouting in a contractility-dependent manner. Our findings suggest that changes of collagen microarchitecture regulate myofibroblast differentiation and fibrosis independent of collagen quantity and bulk stiffness by locally modulating cellular mechanosignaling. These findings have implications for regenerative medicine and anticancer treatments.


Assuntos
Colágeno/ultraestrutura , Miofibroblastos/citologia , Células Estromais/citologia , Tecido Adiposo/citologia , Fenômenos Biomecânicos , Diferenciação Celular , Células Cultivadas , Colágeno/metabolismo , Matriz Extracelular/ultraestrutura , Fibronectinas/metabolismo , Humanos , Mecanotransdução Celular , Miofibroblastos/metabolismo , Miofibroblastos/ultraestrutura , Células Estromais/metabolismo , Células Estromais/ultraestrutura
8.
Am J Pathol ; 190(6): 1236-1255, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32201263

RESUMO

Hyaluronidase (HYAL)-2 is a weak, acid-active, hyaluronan-degrading enzyme broadly expressed in somatic tissues. Aberrant HYAL2 expression is implicated in diverse pathology. However, a significant proportion of HYAL2 is enzymatically inactive; thus the mechanisms through which HYAL2 dysregulation influences pathobiology are unclear. Recently, nonenzymatic HYAL2 functions have been described, and nuclear HYAL2 has been shown to influence mRNA splicing to prevent myofibroblast differentiation. Myofibroblasts drive fibrosis, thereby promoting progressive tissue damage and leading to multimorbidity. This study identifies a novel HYAL2 cytoplasmic function in myofibroblasts that is unrelated to its enzymatic activity. In fibroblasts and myofibroblasts, HYAL2 interacts with the GTPase-signaling small molecule ras homolog family member A (RhoA). Transforming growth factor beta 1-driven fibroblast-to-myofibroblast differentiation promotes HYAL2 cytoplasmic relocalization to bind to the actin cytoskeleton. Cytoskeletal-bound HYAL2 functions as a key regulator of downstream RhoA signaling and influences profibrotic myofibroblast functions, including myosin light-chain kinase-mediated myofibroblast contractility, myofibroblast migration, myofibroblast collagen/fibronectin deposition, as well as connective tissue growth factor and matrix metalloproteinase-2 expression. These data demonstrate that, in certain biological contexts, the nonenzymatic effects of HYAL2 are crucial in orchestrating RhoA signaling and downstream pathways that are important for full profibrotic myofibroblast functionality. In conjunction with previous data demonstrating the influence of HYAL2 on RNA splicing, these findings begin to explain the broad biological effects of HYAL2.


Assuntos
Fibroblastos/metabolismo , Hialuronoglucosaminidase/metabolismo , Miofibroblastos/metabolismo , Transdução de Sinais/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Fibrose/metabolismo , Humanos , Masculino , Processamento de RNA , Ratos
9.
Ann Rheum Dis ; 79(4): 507-517, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32041748

RESUMO

BACKGROUND: Systemic sclerosis (SSc) is characterised by autoimmune activation, tissue and vascular fibrosis in the skin and internal organs. Tissue fibrosis is driven by myofibroblasts, that are known to maintain their phenotype in vitro, which is associated with epigenetically driven trimethylation of lysine 27 of histone 3 (H3K27me3). METHODS: Full-thickness skin biopsies were surgically obtained from the forearms of 12 adult patients with SSc of recent onset. Fibroblasts were isolated and cultured in monolayers and protein and RNA extracted. HOX transcript antisense RNA (HOTAIR) was expressed in healthy dermal fibroblasts by lentiviral induction employing a vector containing the specific sequence. Gamma secretase inhibitors were employed to block Notch signalling. Enhancer of zeste 2 (EZH2) was blocked with GSK126 inhibitor. RESULTS: SSc myofibroblasts in vitro and SSc skin biopsies in vivo display high levels of HOTAIR, a scaffold long non-coding RNA known to direct the histone methyltransferase EZH2 to induce H3K27me3 in specific target genes. Overexpression of HOTAIR in dermal fibroblasts induced EZH2-dependent increase in collagen and α-SMA expression in vitro, as well as repression of miRNA-34A expression and consequent NOTCH pathway activation. Consistent with these findings, we show that SSc dermal fibroblast display decreased levels of miRNA-34a in vitro. Further, EZH2 inhibition rescued miRNA-34a levels and mitigated the profibrotic phenotype of both SSc and HOTAIR overexpressing fibroblasts in vitro. CONCLUSIONS: Our data indicate that the EZH2-dependent epigenetic phenotype of myofibroblasts is driven by HOTAIR and is linked to miRNA-34a repression-dependent activation of NOTCH signalling.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Fibroblastos/metabolismo , MicroRNAs/metabolismo , Miofibroblastos/metabolismo , RNA Longo não Codificante/metabolismo , Receptores Notch/metabolismo , Escleroderma Sistêmico/metabolismo , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Epigênese Genética , Fibrose , Código das Histonas , Humanos , Indóis/farmacologia , Fenótipo , Piridonas/farmacologia , Receptores Notch/antagonistas & inibidores , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/patologia , Transdução de Sinais , Pele/citologia , Pele/metabolismo , Pele/patologia
10.
Toxicol Appl Pharmacol ; 389: 114882, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31953203

RESUMO

Pulmonary fibrosis is a prototypic chronic progressive lung disease with high morbidity and mortality worldwide. Novel effective therapeutic agents are urgently needed owing to the limited treatment options in clinic. Herein, nagilactone D (NLD), a natural dinorditerpenoid obtained from Podocarpus nagi, was found to suppress transforming growth factor-ß1 (TGF-ß1)-mediated fibrotic process in vitro and bleomycin (BLM)-induced pulmonary fibrosis in vivo. NLD attenuated TGF-ß1-induced expression of fibrotic markers including type I and III collagen, fibronectin, α-SMA, and CTGF in human pulmonary fibroblasts (WI-38 VA-13 and HLF-1 cells). Mechanism study indicated that NLD suppressed TGF-ß1-induced up-regulation of TßR I, and Smad2 phosphorylation, nuclear translocation, and transcriptional activation. Moreover, NLD ameliorated BLM-induced histopathological abnormalities in the lungs of experimental fibrotic mice, suppressed synthesis of relative fibrotic markers and fibroblast-to-myofibroblast transition, as well as BLM-induced up-regulation of TßR I expression and Smad signaling in mouse lungs. These data collectively support NLD to be a potential therapeutic agent for pulmonary fibrosis.


Assuntos
Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Proteína Smad2/metabolismo , Terpenos/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Biomarcadores/metabolismo , Bleomicina/farmacologia , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Fibrose Pulmonar/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Nat Commun ; 11(1): 519, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980640

RESUMO

Fibroblastic reticular cells (FRCs) are immunologically specialized myofibroblasts of lymphoid organ, and FRC maturation is essential for structural and functional properties of lymph nodes (LNs). Here we show that YAP and TAZ (YAP/TAZ), the final effectors of Hippo signaling, regulate FRC commitment and maturation. Selective depletion of YAP/TAZ in FRCs impairs FRC growth and differentiation and compromises the structural organization of LNs, whereas hyperactivation of YAP/TAZ enhances myofibroblastic characteristics of FRCs and aggravates LN fibrosis. Mechanistically, the interaction between YAP/TAZ and p52 promotes chemokine expression that is required for commitment of FRC lineage prior to lymphotoxin-ß receptor (LTßR) engagement, whereas LTßR activation suppresses YAP/TAZ activity for FRC maturation. Our findings thus present YAP/TAZ as critical regulators of commitment and maturation of FRCs, and hold promise for better understanding of FRC-mediated pathophysiologic processes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular , Fibroblastos/metabolismo , Linfonodos/citologia , Transativadores/metabolismo , Adipócitos/metabolismo , Animais , Quimiocinas/metabolismo , Fibroblastos/ultraestrutura , Linfonodos/ultraestrutura , Receptor beta de Linfotoxina/metabolismo , Mesoderma/metabolismo , Camundongos Endogâmicos C57BL , Miofibroblastos/metabolismo
12.
Am J Respir Cell Mol Biol ; 62(4): 454-465, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31913651

RESUMO

During pulmonary secondary alveolar septation, the rudimentary distal saccule subdivides by extending tissue sheets into the saccular air space, creating alveoli, which open into the alveolar duct. The sheets originate from saccular mesenchymal cells, which contain α-SMA (αSMA [ACTA2]) and abut elastic fibers (myofibroblasts [MF]), characteristics that are shared by cells that subsequently occupy the secondary septal tips. During elongation, collagen fibers are positioned to provide a scaffold for translocating septal mesenchymal cells. We hypothesized that collagen fibers direct the migration, orientation, and location of MFs during septal elongation. To address this hypothesis, we examined how electrospun collagen fibers direct the migration of fibroblasts bearing targeted deletions of PDGFRα (platelet-derived growth factor receptor-α) or Nrp1 (neuropilin-1), after their isolation from lungs that exhibit reduced secondary septation. We observed that deletion of either gene reduced Rac1 activation and the speed of migration of lung fibroblasts (LF) along electrospun fibers. The deletions did not reduce the proportion of LF that displayed collagen-binding integrins and increased the proportion of LF bearing activated ß1-integrin. LF bearing the PDGFRα deletion failed to localize focal adhesions over electrospun fibers, suggesting that they may not appropriately sense and respond to regionally increased stiffness near the fibers. In lungs of mice bearing the PDGFRα deletion, collagen fibers are delocalized from ACTA2-containing MF, and their orientation deviated from the plane of the alveolar walls. Diminished PDGFRα or Nrp1 reduces LF localization to stiffer regions of fibrillar collagen substrates, suggesting that signaling through these receptors enables responsiveness to regional differences in extracellular matrix rigidity.


Assuntos
Colágeno/metabolismo , Fibroblastos/metabolismo , Pulmão/metabolismo , Miofibroblastos/metabolismo , Neuropilina-1/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Actinas/metabolismo , Animais , Matriz Extracelular/metabolismo , Feminino , Adesões Focais/metabolismo , Masculino , Camundongos , Alvéolos Pulmonares/metabolismo , Transdução de Sinais/fisiologia
13.
Nat Commun ; 11(1): 404, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964880

RESUMO

Although fibroblast heterogeneity is recognized in primary tumors, both its characterization in and its impact on metastases remain unknown. Here, combining flow cytometry, immunohistochemistry and RNA-sequencing on breast cancer samples, we identify four Cancer-Associated Fibroblast (CAF) subpopulations in metastatic lymph nodes (LN). Two myofibroblastic subsets, CAF-S1 and CAF-S4, accumulate in LN and correlate with cancer cell invasion. By developing functional assays on primary cultures, we demonstrate that these subsets promote metastasis through distinct functions. While CAF-S1 stimulate cancer cell migration and initiate an epithelial-to-mesenchymal transition through CXCL12 and TGFß pathways, highly contractile CAF-S4 induce cancer cell invasion in 3-dimensions via NOTCH signaling. Patients with high levels of CAFs, particularly CAF-S4, in LN at diagnosis are prone to develop late distant metastases. Our findings suggest that CAF subset accumulation in LN is a prognostic marker, suggesting that CAF subsets could be examined in axillary LN at diagnosis.


Assuntos
Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/metabolismo , Metástase Linfática/patologia , Miofibroblastos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Fibroblastos Associados a Câncer/patologia , Proliferação de Células , Separação Celular , Quimiocina CXCL12/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Linfonodos/citologia , Linfonodos/patologia , Pessoa de Meia-Idade , Miofibroblastos/patologia , Invasividade Neoplásica/patologia , Cultura Primária de Células , Prognóstico , Intervalo Livre de Progressão , Receptores Notch/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Células Tumorais Cultivadas , Microambiente Tumoral
14.
Am J Respir Cell Mol Biol ; 62(2): 191-203, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31486669

RESUMO

The differentiation of fibroblasts into myofibroblasts is critical for the development of fibrotic disorders, including idiopathic pulmonary fibrosis (IPF). Previously, we demonstrated that fibroblasts from patients with IPF exhibit changes in DNA methylation across the genome that contribute to a profibrotic phenotype. One of the top differentially methylated genes identified in our previous study was KCNMB1, which codes for the ß subunit of the large-conductance potassium (BK, also known as MaxiK or KCa1.1) channel. Here, we examined how the expression of KCNMB1 differed between IPF fibroblasts and normal cells, and how BK channels affected myofibroblast differentiation. Fibroblasts from patients with IPF exhibited increased expression of KCNMB1, which corresponded to increased DNA methylation within the gene body. Patch-clamp experiments demonstrated that IPF fibroblasts had increased BK channel activity. Knockdown of KCNMB1 attenuated the ability of fibroblasts to contract collagen gels, and this was associated with a loss of α-smooth muscle actin (SMA) expression. Pharmacologic activation of BK channels stimulated α-SMA expression, whereas BK channel inhibitors blocked the upregulation of α-SMA. The ability of BK channels to enhance α-SMA expression was dependent on intracellular calcium, as activation of BK channels resulted in increased levels of intracellular calcium and the effects of BK agonists were abolished when calcium was removed. Together, our findings demonstrate that epigenetic upregulation of KCNMB1 contributes to increased BK channel activity in IPF fibroblasts, and identify a newfound role for BK channels in myofibroblast differentiation.


Assuntos
Fibrose Pulmonar Idiopática/metabolismo , Subunidades beta do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Miofibroblastos/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Metilação de DNA/fisiologia , Fibroblastos/metabolismo , Humanos , Fibrose Pulmonar Idiopática/genética , Pulmão/metabolismo
15.
Nat Rev Rheumatol ; 16(1): 11-31, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31792399

RESUMO

Organ fibrosis is a lethal outcome of autoimmune rheumatic diseases such as systemic sclerosis. Myofibroblasts are scar-forming cells that are ultimately responsible for the excessive synthesis, deposition and remodelling of extracellular matrix proteins in fibrosis. Advances have been made in our understanding of the mechanisms that keep myofibroblasts in an activated state and control myofibroblast functions. However, the mechanisms that help myofibroblasts to persist in fibrotic tissues remain poorly understood. Myofibroblasts evade apoptosis by activating molecular mechanisms in response to pro-survival biomechanical and growth factor signals from the fibrotic microenvironment, which can ultimately lead to the acquisition of a senescent phenotype. Growing evidence suggests that myofibroblasts and senescent myofibroblasts, rather than being resistant to apoptosis, are actually primed for apoptosis owing to concomitant activation of cell death signalling pathways; these cells are poised to apoptose when survival pathways are inhibited. This knowledge of apoptotic priming has paved the way for new therapies that trigger apoptosis in myofibroblasts by blocking pro-survival mechanisms, target senescent myofibroblast for apoptosis or promote the reprogramming of myofibroblasts into scar-resolving cells. These novel strategies are not only poised to prevent progressive tissue scarring, but also have the potential to reverse established fibrosis and to regenerate chronically injured tissues.


Assuntos
Apoptose , Matriz Extracelular/metabolismo , Miofibroblastos/patologia , Escleroderma Sistêmico/patologia , Animais , Fibrose/metabolismo , Fibrose/patologia , Humanos , Miofibroblastos/metabolismo , Escleroderma Sistêmico/metabolismo
16.
Toxicol Lett ; 321: 103-113, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706003

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with no effective medication. Andrographolide (Andro), extracted from Chinese herbal Andrographis paniculata, could attenuate bleomycin (BLM)-induced pulmonary fibrosis via inhibition of inflammation and oxidative stress, however, the anti-fibrotic mechanisms have not been clarified. Myofibroblasts are the primary cell types responsible for the accumulation of extracellular matrix (ECM) in fibrotic diseases, and targeting fibroblast proliferation and differentiation is an important therapeutic strategy for the treatment of IPF. Hence, this study aimed to investigate the effects of Andro on the fibroblast proliferation and differentiation in the in vivo and in vitro models. The results showed that Andro improved pulmonary function and inhibited BLM-induced fibroblast proliferation and differentiation and ECM deposition in the lungs. In vitro, Andro inhibited proliferation and induced apoptosis of TGF-ß1-stimulated NIH 3T3 fibroblasts and primary lung fibroblasts (PLFs). Andro also inhibited TGF-ß1-induced myofibroblast differentiation and ECM deposition in both cells. We also found that Andro suppressed TGF-ß1-induced Smad2/3 and Erk1/2 activation, suggesting that Smad2/3 and Erk1/2 inactivation mediates Andro-induced effects on TGF-ß1-induced fibroblast proliferation and differentiation. These results indicated that Andro has novel and potent anti-fibrotic effects in lung fibroblasts via inhibition of the proliferation and myofibroblast differentiation of fibroblasts and subsequent ECM deposition, which are modulated by TGF-ß1-mediated Smad-dependent and -independent pathways.


Assuntos
Bleomicina , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibrose Pulmonar Idiopática/prevenção & controle , Pulmão/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Células NIH 3T3 , Ratos Sprague-Dawley , Transdução de Sinais
17.
Proc Natl Acad Sci U S A ; 117(2): 1139-1147, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31879343

RESUMO

Pulmonary inflammatory responses lie under circadian control; however, the importance of circadian mechanisms in the underlying fibrotic phenotype is not understood. Here, we identify a striking change to these mechanisms resulting in a gain of amplitude and lack of synchrony within pulmonary fibrotic tissue. These changes result from an infiltration of mesenchymal cells, an important cell type in the pathogenesis of pulmonary fibrosis. Mutation of the core clock protein REVERBα in these cells exacerbated the development of bleomycin-induced fibrosis, whereas mutation of REVERBα in club or myeloid cells had no effect on the bleomycin phenotype. Knockdown of REVERBα revealed regulation of the little-understood transcription factor TBPL1. Both REVERBα and TBPL1 altered integrinß1 focal-adhesion formation, resulting in increased myofibroblast activation. The translational importance of our findings was established through analysis of 2 human cohorts. In the UK Biobank, circadian strain markers (sleep length, chronotype, and shift work) are associated with pulmonary fibrosis, making them risk factors. In a separate cohort, REVERBα expression was increased in human idiopathic pulmonary fibrosis (IPF) lung tissue. Pharmacological targeting of REVERBα inhibited myofibroblast activation in IPF fibroblasts and collagen secretion in organotypic cultures from IPF patients, thus suggesting that targeting of REVERBα could be a viable therapeutic approach.


Assuntos
Proteínas CLOCK/antagonistas & inibidores , Relógios Circadianos/fisiologia , Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Animais , Bleomicina/efeitos adversos , Proteínas CLOCK/genética , Proteínas CLOCK/uso terapêutico , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Fibrose Pulmonar Idiopática , Integrinas , Pulmão/patologia , Masculino , Células-Tronco Mesenquimais , Camundongos , Camundongos Knockout , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Proteínas Semelhantes à Proteína de Ligação a TATA-Box/metabolismo , Transcriptoma
18.
Arthritis Rheumatol ; 72(6): 1013-1025, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31872544

RESUMO

OBJECTIVE: To investigate the role of the inflammatory lipid mediator leukotriene B4 (LTB4 ) and its receptor, BLT1, in the development and progression of systemic sclerosis (SSc). METHODS: Serum levels of LTB4 were compared in 64 patients with SSc and 80 healthy controls. Skin and lung tissue sections from patients with SSc and healthy donors were immunostained for leukotriene A4 hydrolase (LTA4 H), the critical enzyme for LTB4 synthesis, and BLT1, in combination with different cell markers. In mouse models of SSc using bleomycin or angiotensin II challenge or immunization with the DNA topoisomerase I, genetic or pharmacologic interruption of the LTB4 -BLT1 axis in mice was carried out to assess its effects on systemic disease features and myofibroblast markers. Immunoblotting was performed to examine the signaling pathway in fibroblasts and endothelial cells following stimulation with LTB4 or with serum from SSc patients. RESULTS: Serum LTB4 levels were 44.93% higher in patients with SSc than in matched healthy controls (mean ± SD 220.3 ± 74.75 pg/ml versus 152.0 ± 68.05 pg/ml; P < 0.0001), and this was associated with the patient subsets of SSc-associated interstitial lung disease and diffuse cutaneous SSc. Levels of LTA4 H and BLT1 were increased in lesional areas of the skin and lungs of SSc patients, and both were abundant in myofibroblasts and endothelial cells. Interruption of the LTB4 -BLT1 axis in mouse models of SSc significantly mitigated dermal and pulmonary fibrosis, with 54.00% and 52.65% fewer α-smooth muscle actin-positive myofibroblasts accumulating in the skin and lungs of mice, respectively, after bleomycin challenge. Immunoblotting of cultures with recombinant LTB4 -stimulated fibroblasts and endothelial cells or with serum from SSc patients showed that fibroblast-myofibroblast and endothelial-mesenchymal transitions were promoted via BLT1, and that this was dependent on activation of the phosphatidylinositol 3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR) pathway but independent of the release of transforming growth factor ß (TGFß) by fibroblasts or endothelial cells. CONCLUSION: The LTB4 -BLT1 axis may contribute to fibrosis in SSc by directly promoting myofibroblast differentiation via the PI3K/Akt/mTOR pathway, and this appears to operate independently of autocrine secretion of TGFß.


Assuntos
Leucotrieno B4/sangue , Pulmão/patologia , Receptores do Leucotrieno B4/sangue , Escleroderma Sistêmico/sangue , Pele/patologia , Animais , Estudos de Casos e Controles , Diferenciação Celular , Modelos Animais de Doenças , Fibrose , Humanos , Camundongos , Miofibroblastos/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Transdução de Sinais
19.
Exp Cell Res ; 386(1): 111716, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31734152

RESUMO

BACKGROUND: Emerging evidence demonstrates that epoxyeicosatrienoic acids (EETs) as important active eicosanoids that regulate cardiovascular homeostasis, but the mechanisms underlying its favorable anti-hypertrophic benefits in overpressure model remain obscure. METHODS AND RESULTS: Four weeks after transverse aortic constriction (TAC), TAC mice developed maladaptive cardiac hypertrophy and consequent cardiac failure. Conversely, a cardiotropic adeno-associated viral vector (AAV9) encoding CYP2J2 prevented transverse aortic constriction-induced cardiac hypertrophy with preserved ejection fraction. EET also conferred protection against phenylephrine-induced hypertrophy in H9c2 cardiomyoblasts. Further investigations indicate CYP2J2/EET exerts protection against cardiac hypertrophy through opposing the increase of intracellular Ca2+ level and Ca2+-mediated calcineurin/NFATc3 signaling. Meanwhile, extended myocardial fibrosis in TAC mice was also effectively abolished with the administration of AAV9-2J2. Intriguingly, TAC mice display activated TGF-ß/Samd-3 signaling with decreased Smad-7 expression, whereas AAV9-2J2 attenuated the phosphorylation of Smad-3 without altering TGF-ß expression, whilst preservation of Smad-7. Subsequently, the differentiation of cardiac fibroblasts into myofibroblasts in the presence of TGF-ß1 stimulation was significantly disrupted with EET treatment, accompanied by declined Smad-3 activation and collagen production, whereas inhibition of Smad-7 with SiRNA Smad-7 substantially abrogated these effects of EET on cardiac fibroblasts. CONCLUSIONS: EET has synergistic actions on cardiomyocytes and cardiac fibroblasts, preventing cardiac hypertrophy through inhibition of Ca2+-mediated calcineurin/NFATc3 signaling cascades, and ameliorating myocardial fibrosis dependent on Smad-7. This work further extends the potential mechanisms of EET, providing a novel therapeutic approach for the treatment of pathological remodeling and heart failure.


Assuntos
Ácido 8,11,14-Eicosatrienoico/farmacologia , Calcineurina/metabolismo , Cardiomegalia/prevenção & controle , Cardiotônicos/farmacologia , Fatores de Transcrição NFATC/metabolismo , Proteína Smad7/metabolismo , Ácido 8,11,14-Eicosatrienoico/uso terapêutico , Animais , Cálcio/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiotônicos/uso terapêutico , Linhagem Celular , Células Cultivadas , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
20.
Development ; 147(2)2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31862844

RESUMO

Alveologenesis is an essential developmental process that increases the surface area of the lung through the formation of septal ridges. In the mouse, septation occurs postnatally and is thought to require the alveolar myofibroblast (AMF). Though abundant during alveologenesis, markers for AMFs are minimally detected in the adult. After septation, the alveolar walls thin to allow efficient gas exchange. Both loss of AMFs or retention and differentiation into another cell type during septal thinning have been proposed. Using a novel Fgf18:CreERT2 allele to lineage trace AMFs, we demonstrate that most AMFs are developmentally cleared during alveologenesis. Lung mesenchyme also contains other poorly described cell types, including alveolar lipofibroblasts (ALF). We show that Gli1:CreERT2 marks both AMFs as well as ALFs, and lineage tracing shows that ALFs are retained in adult alveoli while AMFs are lost. We further show that multiple immune cell populations contain lineage-labeled particles, suggesting a phagocytic role in the clearance of AMFs. The demonstration that the AMF lineage is depleted during septal thinning through a phagocytic process provides a mechanism for the clearance of a transient developmental cell population.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Miofibroblastos/metabolismo , Organogênese , Alvéolos Pulmonares/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos , Linhagem da Célula , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica no Desenvolvimento , Mesoderma/citologia , Camundongos Endogâmicos C57BL , Modelos Biológicos , Miofibroblastos/citologia , Fagocitose , Fatores de Tempo
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