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1.
EMBO J ; 39(22): e105220, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-32930455

RESUMO

When dormant naïve T cells first become activated by antigen-presenting cells, they express the autocrine growth factor IL-2 which transforms them into rapidly dividing effector T cells. During this process, hundreds of genes undergo epigenetic reprogramming for efficient activation, and also for potential reactivation after they return to quiescence as memory T cells. However, the relative contributions of IL-2 and T cell receptor signaling to this process are unknown. Here, we show that IL-2 signaling is required to maintain open chromatin at hundreds of gene regulatory elements, many of which control subsequent stimulus-dependent alternative pathways of T cell differentiation. We demonstrate that IL-2 activates binding of AP-1 and STAT5 at sites that can subsequently bind lineage-determining transcription factors, depending upon what other external factors exist in the local T cell environment. Once established, priming can also be maintained by the stroma-derived homeostatic cytokine IL-7, and priming diminishes if Il7r is subsequently deleted in vivo. Hence, IL-2 is not just a growth factor; it lays the foundation for T cell differentiation and immunological memory.


Assuntos
Diferenciação Celular/fisiologia , Fator VII/metabolismo , Interleucina-2/metabolismo , Interleucina-7/metabolismo , Animais , Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Cromatina/metabolismo , Citocinas/metabolismo , Epigenômica , Fator VII/genética , Regulação da Expressão Gênica , Memória Imunológica , Interleucina-2/genética , Interleucina-7/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fatores de Transcrição
2.
Planta ; 258(2): 26, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37354348

RESUMO

MAIN CONCLUSION: LBD18 and IAA14 antagonistically interact with ARF7 through the electrostatic faces in the ARF7PB1 domain, modulating ARF7 transcriptional activity. Auxin Response Factor 7 (ARF7)/ARF19 control lateral root development by directly activating Lateral Organ Boundaries Domain 16 (LBD16)/LBD18 genes in Arabidopsis. LBD18 upregulates ARF19 expression by binding to the ARF19 promoter. It also interacts with ARF7 through the Phox and Bem1 (PB1) domain to enhance the ARF7 transcriptional activity, forming a dual mode of positive feedback loop. LBD18 competes with the repressor indole-3-acetic acid 14 (IAA14) for ARF7 binding through the PB1 domain. In this study, we examined the molecular determinant of the ARF7 PB1 domain for interacting with LBD18 and showed that the electronic faces in the ARF7 PB1 domain are critical for interacting with LBD18 and IAA14/17. We used a luminescence complementation imaging assay to determine protein-protein interactions. The results showed that mutation of the invariant lysine residue and the OPCA motif in the PB1 domain in ARF7 significantly reduces the protein interaction between ARF7 and LBD18. Transient gene expression assays with Arabidopsis protoplasts showed that IAA14 suppressed transcription-enhancing activity of LBD18 on the LUC reporter gene fused to the ARF19 promoter harboring an auxin response element, but mutation of the invariant lysine residue and OPCA motif in the PB1 domain of IAA14 reduced the repression capability of IAA14 for transcription-enhancing activity of LBD18. We further showed that the same mutation in the PB1 domain of IAA14 reduces its repression capability, thereby increasing the LUC activity induced by both ARF7 and LBD18 compared with IAA14. These results suggest that LBD18 competes with IAA14 for ARF7 binding via the electrostatic faces of the ARF7 PB1 domain to modulate ARF7 transcriptional activity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fator VII/genética , Fator VII/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Lisina/metabolismo , Raízes de Plantas/metabolismo , Fatores de Transcrição/metabolismo
3.
Int J Mol Sci ; 24(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36982544

RESUMO

Factor VII activating protease (FSAP) was first isolated from human plasma less than 30 years ago. Since then, many research groups have described the biological properties of this protease and its role in hemostasis and other processes in humans and other animals. With the progress of knowledge about the structure of FSAP, several of its relationships with other proteins or chemical compounds that may modulate its activity have been explained. These mutual axes are described in the present narrative review. The first part of our series of manuscripts on FSAP describes the structure of this protein and the processes leading to the enhancement and inhibition of its activities. The following parts, II and III, concern the role of FSAP in hemostasis and in the pathophysiology of human diseases, with particular emphasis on cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Fator VII , Animais , Humanos , Fator VII/metabolismo , Serina Endopeptidases/metabolismo , Peptídeo Hidrolases , Hemostasia/fisiologia
4.
Biochemistry ; 61(16): 1694-1703, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35853076

RESUMO

Factor VII (FVII) is a serine protease with a key role in initiating the coagulation cascade. It is part of a family of vitamin K-dependent clotting proteins, which require vitamin K for formation of their specialized membrane-binding domains (Gla domains). Membrane binding of the FVII Gla domain is critical to the activity of FVII, mediating the formation of its complex with other clotting factors. While Gla domains among coagulation factors are highly conserved in terms of amino acid sequence and structure, they demonstrate differential binding specificity toward anionic lipids. Although most Gla domain-containing clotting proteins display a strong preference for phosphatidylserine (PS), it has been demonstrated that FVII and protein C instead bind preferentially to phosphatidic acid (PA). We have developed the first model of the FVII Gla domain bound to PA lipids in membranes containing PA, the highly mobile membrane mimetic model, which accelerates slow diffusion of lipids in molecular dynamics simulations and therefore facilitates the membrane binding process and enhances sampling of lipid interactions. Simulations were performed using atomic level molecular dynamics, requiring a fixed charge to all atoms. The overall charge assigned to each PA lipid for this study was -1. We also developed an additional model of the FVII Gla domain bound to a 1:1 PS/PC membrane and compared the modes of binding of PS and PA lipids to FVII, allowing us to identify potential PA-specific binding sites.


Assuntos
Fator VII , Ácidos Fosfatídicos , Sequência de Aminoácidos , Sítios de Ligação , Fatores de Coagulação Sanguínea , Fator VII/química , Fator VII/metabolismo , Fosfatidilserinas/metabolismo , Vitamina K/metabolismo
5.
Pflugers Arch ; 474(2): 217-229, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34870751

RESUMO

Proteolytic activation of the epithelial sodium channel (ENaC) by aberrantly filtered serine proteases is thought to contribute to renal sodium retention in nephrotic syndrome. However, the identity of the responsible proteases remains elusive. This study evaluated factor VII activating protease (FSAP) as a candidate in this context. We analyzed FSAP in the urine of patients with nephrotic syndrome and nephrotic mice and investigated its ability to activate human ENaC expressed in Xenopus laevis oocytes. Moreover, we studied sodium retention in FSAP-deficient mice (Habp2-/-) with experimental nephrotic syndrome induced by doxorubicin. In urine samples from nephrotic humans, high concentrations of FSAP were detected both as zymogen and in its active state. Recombinant serine protease domain of FSAP stimulated ENaC-mediated whole-cell currents in a time- and concentration-dependent manner. Mutating the putative prostasin cleavage site in γ-ENaC (γRKRK178AAAA) prevented channel stimulation by the serine protease domain of FSAP. In a mouse model for nephrotic syndrome, active FSAP was present in nephrotic urine of Habp2+/+ but not of Habp2-/- mice. However, Habp2-/- mice were not protected from sodium retention compared to nephrotic Habp2+/+ mice. Western blot analysis revealed that in nephrotic Habp2-/- mice, proteolytic cleavage of α- and γ-ENaC was similar to that in nephrotic Habp2+/+ animals. In conclusion, active FSAP is excreted in the urine of nephrotic patients and mice and activates ENaC in vitro involving the putative prostasin cleavage site of γ-ENaC. However, endogenous FSAP is not essential for sodium retention in nephrotic mice.


Assuntos
Canais Epiteliais de Sódio/metabolismo , Fator VII/metabolismo , Rim/metabolismo , Síndrome Nefrótica/metabolismo , Peptídeo Hidrolases/metabolismo , Sódio/metabolismo , Animais , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Humanos , Transporte de Íons/efeitos dos fármacos , Transporte de Íons/fisiologia , Rim/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteólise/efeitos dos fármacos , Serina Endopeptidases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Xenopus laevis/metabolismo
6.
J Gene Med ; 24(2): e3398, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34786791

RESUMO

BACKGROUND: Hereditary factor VII deficiency (FVIID) is a rare congenital autosomal recessive bleeding disorder. In clinical manifestations, its onset is caused by variant of the F7 gene (NM_019616) with strong heterogeneity. We identified a family with hematuria caused by a novel F7 compound heterozygous variant and investigated the FVIID-dependent mechanism impacted by these variants. METHODS: Coagulation factors in the proband were functionally verified. We located pathogenic variants in relevant genes using next-generation sequencing after target enrichment and verified them by Sanger sequencing. We examined the coagulation activity and secretion pattern of recombinant FVII variants expressed in cells and observed their location and stability by immunofluorescence. RESULTS: We found a missense variant c.1207G>A (p.Gly403Ser) and a frameshift variant c.154_155del (p.Arg53fs) in the F7 gene of the proband. FVII activity tests showed that the variants significantly decreased its presence in the cell culture supernatant. Moreover, the R53fs mutant lacked the FVII functional domain and had no detectable activity. Immunofluorescence indicated that the p.Gly403Ser variant was distributed to the cell membrane and cytoplasm, whereas the FVII R53fs variant was not detected. Deficient FVII protein function and severe coagulation disorder are the likely causes of hematuria and other bleeding symptoms in the proband. CONCLUSIONS: The newly discovered F7 gene variants enrich the spectrum of hereditary FVII deficiency and provide a new foundation for the diagnosis and treatment of this type of coagulation disorder.


Assuntos
Deficiência do Fator VII , Fator VII/genética , Fator VII/metabolismo , Deficiência do Fator VII/congênito , Deficiência do Fator VII/genética , Feminino , Hematúria/genética , Humanos , Masculino , Mutação , Mutação de Sentido Incorreto
7.
J Neuroinflammation ; 19(1): 138, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690769

RESUMO

BACKGROUND: Inflammation and coagulation are linked and pathogenic in neuroinflammatory diseases. Protease-activated receptor 1 (PAR1) can be activated both by thrombin, inducing increased inflammation, and activated protein C (aPC), inducing decreased inflammation. Modulation of the aPC-PAR1 pathway may prevent the neuroinflammation associated with PAR1 over-activation. METHODS: We synthesized a group of novel molecules based on the binding site of FVII/aPC to the endothelial protein C receptor (EPCR). These molecules modulate the FVII/aPC-EPCR pathway and are therefore named FEAMs-Factor VII, EPCR, aPC Modulators. We studied the molecular and behavioral effects of a selected FEAM in neuroinflammation models in-vitro and in-vivo. RESULTS: In a lipopolysaccharide (LPS) induced in-vitro model, neuroinflammation leads to increased thrombin activity compared to control (2.7 ± 0.11 and 2.23 ± 0.13 mU/ml, respectively, p = 0.01) and decreased aPC activity (0.57 ± 0.01 and 1.00 ± 0.02, respectively, p < 0.0001). In addition, increased phosphorylated extracellular regulated kinase (pERK) (0.99 ± 0.13, 1.39 ± 0.14, control and LPS, p < 0.04) and protein kinase B (pAKT) (1.00 ± 0.09, 2.83 ± 0.81, control and LPS, p < 0.0002) levels indicate PAR1 overactivation, which leads to increased tumor necrosis factor-alpha (TNF-α) level (1.00 ± 0.04, 1.35 ± 0.12, control and LPS, p = 0.02). In a minimal traumatic brain injury (mTBI) induced neuroinflammation in-vivo model in mice, increased thrombin activity, PAR1 activation, and TNF-α levels were measured. Additionally, significant memory impairment, as indicated by a lower recognition index in the Novel Object Recognition (NOR) test and Y-maze test (NOR: 0.19 ± 0.06, -0.07 ± 0.09, p = 0.03. Y-Maze: 0.50 ± 0.03, 0.23 ± 0.09, p = 0.02 control and mTBI, respectively), as well as hypersensitivity by hot-plate latency (16.6 ± 0.89, 12.8 ± 0.56 s, control and mTBI, p = 0.01), were seen. FEAM prevented most of the molecular and behavioral negative effects of neuroinflammation in-vitro and in-vivo, most likely through EPCR-PAR1 interactions. CONCLUSION: FEAM is a promising tool to study neuroinflammation and a potential treatment for a variety of neuroinflammatory diseases.


Assuntos
Proteína C , Receptor PAR-1 , Animais , Receptor de Proteína C Endotelial/metabolismo , Fator VII/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Doenças Neuroinflamatórias , Proteína C/metabolismo , Proteína C/uso terapêutico , Receptor PAR-1/metabolismo , Transdução de Sinais , Trombina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Fish Shellfish Immunol ; 128: 113-122, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35931290

RESUMO

Interferon (IFN)-induced protein 35 (IFI35, also known as IFP35), a member of IFN induced genes (ISGs), participates in virus infection, cancer progression and the chronic inflammatory diseases. However, its roles during fish nodavirus infection still remained largely unknown. In the present study, a homolog of IFI35 from orange spotted grouper (Epinephelus coioides) (EcIFI35) was cloned and characterized. The open reading frame of EcIFI35 was composed of 1,128 bp, and encoded a 375 amino acid polypeptide, which contained two conserved N-myc-interactor (Nmi)/IFP35 domains (NIDs). Homology analysis indicated that EcIFI35 shared 95.73% and 31.96% identity with homologs of giant grouper (E. lanceolatus) and human (Homo sapiens), respectively. The transcription of EcIFI35 was significantly up-regulated in grouper spleen (GS) cells after challenged with red-spotted grouper nervous necrosis virus (RGNNV), polyinosinic:polycytidylic acid [poly(I:C)] or lipopolysaccharide (LPS). The subcellular localization analysis showed that EcIFI35 encoded a cytoplasmic protein. The ectopic expression of EcIFI35 inhibited RGNNV replication by reducing viral genes transcription and protein synthesis. Co-immunoprecipitation (Co-IP) assay demonstrated that EcIFI35 interacted with RGNNV coat protein (CP), and partly co-localized with CP. EcIFI35 overexpression promoted the expression of IFN-related molecules and pro-inflammatory factors, including IFN regulatory factor 7 (IRF7), mitochondrial antiviral signaling protein (MAVS) and myxovirus resistance gene I (MxI), nuclear factor κB (NF-κB), interleukin 6 (IL-6) and IL-8. Together, our results revealed that EcIFI35 interacted with CP and inhibited fish nodavirus replication through positively regulated host innate immune response.


Assuntos
Bass , Infecções por Vírus de DNA , Doenças dos Peixes , Nodaviridae , Sequência de Aminoácidos , Aminoácidos/metabolismo , Animais , Antivirais , Fator VII/genética , Fator VII/metabolismo , Proteínas de Peixes/química , Regulação da Expressão Gênica , Humanos , Imunidade Inata/genética , Interferons/metabolismo , Interleucina-6/genética , Interleucina-8/genética , Lipopolissacarídeos , NF-kappa B/metabolismo , Nodaviridae/fisiologia , Poli I-C/farmacologia , Alinhamento de Sequência
9.
Blood ; 133(9): 967-977, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30642921

RESUMO

Factor VII (FVII) is an important component of the coagulation cascade. Few genetic loci regulating FVII activity and/or levels have been discovered to date. We conducted a meta-analysis of 9 genome-wide association studies of plasma FVII levels (7 FVII activity and 2 FVII antigen) among 27 495 participants of European and African ancestry. Each study performed ancestry-specific association analyses. Inverse variance weighted meta-analysis was performed within each ancestry group and then combined for a trans-ancestry meta-analysis. Our primary analysis included the 7 studies that measured FVII activity, and a secondary analysis included all 9 studies. We provided functional genomic validation for newly identified significant loci by silencing candidate genes in a human liver cell line (HuH7) using small-interfering RNA and then measuring F7 messenger RNA and FVII protein expression. Lastly, we used meta-analysis results to perform Mendelian randomization analysis to estimate the causal effect of FVII activity on coronary artery disease, ischemic stroke (IS), and venous thromboembolism. We identified 2 novel (REEP3 and JAZF1-AS1) and 6 known loci associated with FVII activity, explaining 19.0% of the phenotypic variance. Adding FVII antigen data to the meta-analysis did not result in the discovery of further loci. Silencing REEP3 in HuH7 cells upregulated FVII, whereas silencing JAZF1 downregulated FVII. Mendelian randomization analyses suggest that FVII activity has a positive causal effect on the risk of IS. Variants at REEP3 and JAZF1 contribute to FVII activity by regulating F7 expression levels. FVII activity appears to contribute to the etiology of IS in the general population.


Assuntos
Isquemia Encefálica/etiologia , Fator VII/genética , Estudo de Associação Genômica Ampla , Proteínas de Membrana Transportadoras/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Proteínas Correpressoras , Estudos de Coortes , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Proteínas de Ligação a DNA , Fator VII/metabolismo , Feminino , Seguimentos , Loci Gênicos , Predisposição Genética para Doença , Humanos , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Fenótipo , Prognóstico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/metabolismo , Tromboembolia Venosa/patologia
10.
Protein Expr Purif ; 186: 105920, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34044134

RESUMO

Many proteins produced in CHO cells need evaluation for their clinical and commercial potential. Traditional methods based on stable clone generation are slow and unsuitable for screening larger numbers of proteins, while transient expression technologies are fast but unpredictable regarding product quality and lacking an optional path to subcloning. The STEP® vector technology introduced here combines the best properties of both methods. STEP® vectors contain a strong transcriptional cassette driving expression of a bicistronic mRNA. The gene-of-interest (GOI) is cloned upstream of a functionally impaired zeocin resistance gene (FI-Zeo) whose translation is coupled to that of the GOI through an IRES. Stable transfected cells surviving zeocin selection produce high levels of FI-Zeo and thus, high levels of the GOI-encoded protein. By using different spacers, the translational coupling efficiency and selection strength can be controlled allowing maximization of expression of any GOI. Production of laronidase and factor VII (FVII) is presented as examples of unrelated, difficult-to-express (DTE) proteins. First step is rapid generation of transfected pools with the STEP® vectors. All high expressing surviving pools showed high product quality homogeneity as did monoclonal cell lines obtained from the top pools. Up to 500 µg/mL laronidase was obtained with virtually identical glycosylation profile as reference product. For FVII, cell specific productivity of 0.45 pg/cell/day with 50 IU/µg protein matched highest reported levels of reference product even before process development. Taken together, STEP® vector technology is ideally suited for rapid, small to large-scale production of DTE proteins compared to traditional methods.


Assuntos
Vetores Genéticos/genética , Plasmídeos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Animais , Células CHO , Clonagem Molecular , Cricetinae , Cricetulus , Fator VII/genética , Fator VII/metabolismo , Iduronidase/genética , Iduronidase/metabolismo , Transfecção/métodos
11.
BMC Cardiovasc Disord ; 21(1): 93, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593303

RESUMO

BACKGROUND: Both exercise and cold exposure increase blood coagulation potential but their combined effects are not known. The purpose of the present study was to assess blood coagulation factors in response to submaximal exercise in the cold environment among patients with stable coronary artery disease (CAD). METHODS: Sixteen men (61.1 ± 7.1 years) with stable CAD participated in three 30-min experimental conditions (seated rest in - 15 °C and exercise in both + 22 °C and - 15 °C) in random order. The employed exercise consisted of brisk walking (66-69% of maximal heart rate). Factor VII (FVII), fibrinogen, D-dimer and von Willebrand factor (vWF) were analyzed from blood samples obtained before, immediately and one hour after each experiment. RESULTS: On average, FVII activity (95% confidence interval, CI) was 123 (108-143) %, 123 (106-140) %, 121 (103-139) % (baseline, recovery 1, recovery 2), fibrinogen concentration (95% CI) 3.81 (3.49-4.12) g/l, 3.71 (3.34-4.08) g/l, 3.65 (3.26-4.05) g/l, D-dimer concentration (95% CI) 0.42 (0.28-0.56) µg/ml, 0.42 (0.29-.55) µg/ml and 0.39 (0.29-0.49) µg/ml, and vWF activity (95% CI) 184 (135-232) %, 170 (128-212) % and 173 (129-217) % after exercise in the cold. Average FVII activity varied from 122 to 123%, fibrinogen concentration from 3.71 to 3.75 g/l, D-dimer concentration from 0.35 to 0.51 µg/ml and von Willebrand factor activity from 168 to 175% immediately after each three experimental condition. CONCLUSIONS: Our findings suggest that submaximal lower body exercise carried out in a cold environment does not significantly affect blood coagulation parameters among patients with stable CAD.


Assuntos
Coagulação Sanguínea , Temperatura Baixa , Doença da Artéria Coronariana/sangue , Exercício Físico , Idoso , Biomarcadores/sangue , Doença da Artéria Coronariana/diagnóstico , Fator VII/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Fatores de Tempo , Fator de von Willebrand/metabolismo
12.
Haematologica ; 105(3): 829-837, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31273093

RESUMO

Despite the exhaustive screening of F7 gene exons and exon-intron boundaries and promoter region, a significant proportion of mutated alleles remains unidentified in patients with coagulation factor VII deficiency. Here, we applied next-generation sequencing to 13 FVII-deficient patients displaying genotype-phenotype discrepancies upon conventional sequencing, and identified six rare intronic variants. Computational analysis predicted splicing effects for three of them, which would strengthen (c.571+78G>A; c.806-329G>A) or create (c.572-392C>G) intronic 5' splice sites (5'ss). In F7 minigene assays, the c.806-329G>A was ineffective while the c.571+78G>A change led to usage of the +79 cryptic 5'ss with only trace levels of correct transcripts (3% of wild-type), in accordance with factor VII activity levels in homozygotes (1-3% of normal). The c.572-392C>G change led to pseudo-exonization and frame-shift, but also substantial levels of correct transcripts (approx. 70%). However, this variant was associated with the common F7 polymorphic haplotype, predicted to further decrease factor VII levels; this provided some kind of explanation for the 10% factor VII levels in the homozygous patient. Intriguingly, the effect of the c.571+78G>A and c.572-392C>G changes, and particularly of the former (the most severe and well-represented in our cohort), was counteracted by antisense U7snRNA variants targeting the intronic 5'ss, thus demonstrating their pathogenic role. In conclusion, the combination of next-generation sequencing of the entire F7 gene with the minigene expression studies elucidated the molecular bases of factor VII deficiency in 10 of 13 patients, thus improving diagnosis and genetic counseling. It also provided a potential therapeutic approach based on antisense molecules that has been successfully exploited in other disorders.


Assuntos
Deficiência do Fator VII , Éxons , Fator VII/genética , Fator VII/metabolismo , Deficiência do Fator VII/diagnóstico , Deficiência do Fator VII/genética , Deficiência do Fator VII/terapia , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Mutação , Splicing de RNA
13.
J Nutr ; 150(8): 2089-2100, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492148

RESUMO

BACKGROUND: Factor VIIc, fibrinogen, and plasminogen activator inhibitor 1 (PAI-1) are cardiovascular disease (CVD) risk factors and are modulated, in part, by fat type and amount. OBJECTIVE: We evaluated fat type and amount on the primary outcomes: factor VIIc, fibrinogen, and PAI-1. METHODS: In the Dietary Effects on Lipoproteins and Thrombogenic Activity (DELTA) Trial, 2 controlled crossover feeding studies evaluated substituting carbohydrate or MUFAs for SFAs. Study 1: healthy participants (n = 103) were provided with (8 wk) an average American diet [AAD; designed to provide 37% of energy (%E) as fat, 16% SFA], a Step 1 diet (30%E fat, 9% SFA), and a diet low in SFA (Low-Sat; 26%E fat, 5% SFA). Study 2: participants (n = 85) at risk for CVD and metabolic syndrome (MetSyn) were provided with (7 wk) an AAD, a step 1 diet, and a high-MUFA diet (designed to provide 37%E fat, 8% SFA, 22% MUFA). RESULTS: Study 1: compared with AAD, the Step 1 and Low-Sat diets decreased mean factor VIIc by 1.8% and 2.6% (overall P = 0.0001), increased mean fibrinogen by 1.2% and 2.8% (P = 0.0141), and increased mean square root PAI-1 by 0.0% and 6.0% (P = 0.0037), respectively. Study 2: compared with AAD, the Step 1 and high-MUFA diets decreased mean factor VIIc by 4.1% and 3.2% (overall P < 0.0001), increased mean fibrinogen by 3.9% and 1.5% (P = 0.0083), and increased mean square-root PAI-1 by 2.0% and 5.8% (P = 0.1319), respectively. CONCLUSIONS: Replacing SFA with carbohydrate decreased factor VIIc and increased fibrinogen in healthy and metabolically unhealthy individuals and also increased PAI-1 in healthy subjects. Replacing SFA with MUFA decreased factor VIIc and increased fibrinogen but less than carbohydrate. Our results indicate an uncertain effect of replacing SFA with carbohydrate or MUFA on cardiometabolic risk because of small changes in hemostatic factors and directionally different responses to decreasing SFA. This trial was registered at https://clinicaltrials.gov/ct2/show/NCT00000538?term=NCT00000538&rank=1 as NCT00000538.


Assuntos
Doenças Cardiovasculares/metabolismo , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/farmacologia , Fator VII/metabolismo , Fibrinogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Adulto , Idoso , Dieta , Gorduras na Dieta/classificação , Fator VII/genética , Feminino , Fibrinogênio/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Hemostasia , Humanos , Masculino , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/genética , Fatores de Risco , Adulto Jovem
14.
Biochem J ; 476(19): 2909-2926, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31537632

RESUMO

The mechanism of generation of factor VIIa, considered the initiating protease in the tissue factor-initiated extrinsic limb of blood coagulation, is obscure. Decreased levels of plasma VIIa in individuals with congenital factor IX deficiency suggest that generation of VIIa is dependent on an activation product of factor IX. Factor VIIa activates IX to IXa by a two-step removal of the activation peptide with cleavages occurring after R191 and R226. Factor IXaα, however, is IX cleaved only after R226, and not after R191. We tested the hypothesis that IXaα activates VII with mutant IX that could be cleaved only at R226 and thus generate only IXaα upon activation. Factor IXaα demonstrated 1.6% the coagulant activity of IXa in a contact activation-based assay of the intrinsic activation limb and was less efficient than IXa at activating factor X in the presence of factor VIIIa. However, IXaα and IXa had indistinguishable amidolytic activity, and, strikingly, both catalyzed the cleavage required to convert VII to VIIa with indistinguishable kinetic parameters that were augmented by phospholipids, but not by factor VIIIa or tissue factor. We propose that IXa and IXaα participate in a pathway of reciprocal activation of VII and IX that does not require a protein cofactor. Since both VIIa and activated IX are equally plausible as the initiating protease for the extrinsic limb of blood coagulation, it might be appropriate to illustrate this key step of hemostasis as currently being unknown.


Assuntos
Coagulação Sanguínea/fisiologia , Fator IX/metabolismo , Fator VII/metabolismo , Fator VIIa/metabolismo , Fator X/metabolismo , Células HEK293 , Humanos , Cinética , Proteínas Recombinantes/metabolismo
15.
J Mol Cell Cardiol ; 127: 1-10, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30500376

RESUMO

The mechanisms leading to atherothrombosis from "vulnerable plaque" are more complex than initially proposed. We aimed to clarify whether plaque thrombogenicity is critical in atherothrombosis in mice. In a murine model of plaque destabilization, we enhanced plaque thrombogenicity by systemically overexpressing murine tissue factor (TF) by adenovirus-mediated gene transfer. The potential effects and mechanisms of TF on plaque destabilization were examined in cultured human aortic smooth muscle cells (HASMCs), RAW264.7 cells and human umbilical vein endothelial cells (HUVECs). To elucidate the TF noncoagulant effects on plaque destabilization, TF-overexpressed mice were treated with the protease-activated receptor 2 (PAR-2) antagonist ENMD-1068. In TF-overexpressing apolipoprotein (E)-deficient (ApoE-/-) mice, 67% (8 of 12) of carotid plaques exhibited plaque disruption and atherothrombosis. Moreover, 58% (7 of 12) showed plaque hemorrhage, including 1 due to plaque disruption, 4 neovascularization and 2 both. In contrast, only 17% (2 of 12) of control mice showed atherothrombosis, both with plaque hemorrhage but no neovascularization. On PCR, TF overexpression increased the expression of inflammatory factors. In cultured cells, the TF-FVIIa complex enhanced the expression of inflammatory factors and a vicious cycle of inflammation. Also, TF-FVIIa complex induced intra-plaque angiogenesis via PAR-2. ENMD-1068 treatment significantly inhibited the expression of inflammatory factors and neovascularization, and the incidence of intra-plaque hemorrhage decreased in TF-overexpressing mice. In conclusions, TF overexpression enhanced plaque thrombogenicity, which played a pivotal role in atherothrombosis in ApoE-/- mice. In addition, TF promoted plaque instability by activating inflammatory and proangiogenic effects via TF-FVIIa/PAR-2 signaling.


Assuntos
Apolipoproteínas E/deficiência , Placa Aterosclerótica/patologia , Tromboplastina/metabolismo , Trombose/patologia , Animais , Apolipoproteínas E/metabolismo , Fator VII/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/metabolismo , Neovascularização Fisiológica , Células RAW 264.7 , Receptor PAR-2/metabolismo
16.
J Gastroenterol Hepatol ; 34(10): 1851-1859, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30884543

RESUMO

BACKGROUND AND AIM: Bioartificial livers (BALs) are considered as a solution to bridge patients with acute liver failure to liver transplantation or to assist in spontaneous recovery for patients with end-stage liver disease. Pig is the best donor of hepatocytes for BALs in clinical trials, because metabolic and detoxification function of its liver are close to human. However, using pig hepatocytes for BALs remains controversial for safety concern owing to nonhuman proteins secretion. Herein, we attempt to establish modified pigs expressing humanized liver proteins, blood-coagulation factor VII (F7), and albumin (ALB). These pigs should also be porcine endogenous retrovirus subtype C (PERV-C) free so that their ability of transmitting PERV to human could be diminished seriously. METHODS: We devised both homology-dependent and independent knock-in approaches to insert a fusion of hF7 and hALB gene downstream the site of pig endogenous F7 promoter in pig fetal fibroblasts negative for PERV-C. The modified pigs were then generated through somatic cell nuclear transfer. RESULTS: We obtained 14 and 10 cloned pigs by homology-dependent and independent approaches, respectively. Among them, 19 cloned pigs were with expected gene modification and 13 are alive to date. These modified pigs can successfully express hF7 and hALB in the liver and serum, and the expressed hF7 exhibits normal coagulation activity. CONCLUSIONS: The gene-edited pigs expressing hF7 and hALB in the liver were generated successfully. We anticipate that our pigs could provide an alternative cell source for BALs as a promising treatment for patients with acute liver failure.


Assuntos
Fator VII/genética , Fibroblastos/metabolismo , Edição de Genes , Técnicas de Introdução de Genes , Hepatócitos/metabolismo , Fígado Artificial , Albumina Sérica Humana/genética , Sus scrofa/genética , Animais , Animais Geneticamente Modificados , Linhagem Celular , Fator VII/metabolismo , Fibroblastos/transplante , Genótipo , Hepatócitos/transplante , Fenótipo , Albumina Sérica Humana/metabolismo , Transplante Heterólogo
17.
Ann Hepatol ; 18(4): 627-632, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31097395

RESUMO

INTRODUCTION AND OBJECTIVES: For long, bleeding in cirrhotic patients has been associated with acquired coagulation disorders. The aim of our study was to investigate the impact of acquired coagulation disorders on bleeding risk in cirrhotic patients. MATERIALS AND METHODS: Blood samples were collected from 51 cirrhotic patients with (H+) or without (H-) bleeding events and 50 controls matched by age and sex. Thrombin generation was assessed as endogenous thrombin potential (ETP). Hemostatic balance was assessed by means of ratios of pro- to anticoagulant factors and by ETP ratio with/without protein C (PC) activator (ETP ratio). RESULTS: Bleeding events occurred in 9 patients (17.6%). Compared with controls, VIII/anticoagulant factors, VII/PC and XII/PC were significantly higher in (H+) patients. No significant difference as regards all ratios across patient groups was detected. ETP ratio was significantly higher in (H+) patients than in controls (p=0.017). However, there was no significant difference between patient groups as regards ETP ratio. CONCLUSION: Hemostatic balance is shifted toward a hypercoagulability state even in cirrhotic patients who experienced bleeding. These findings provide evidence against traditional concept of hemostasis-related bleeding tendency in cirrhotic patients.


Assuntos
Transtornos da Coagulação Sanguínea/sangue , Hemorragia/sangue , Cirrose Hepática/sangue , Trombofilia/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Coagulação Sanguínea , Estudos de Casos e Controles , Fator VII/metabolismo , Fator VIII/metabolismo , Fator XII/metabolismo , Humanos , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Proteína C/metabolismo , Tempo de Protrombina , Risco , Trombina/metabolismo , Adulto Jovem
18.
BMC Med Genet ; 19(1): 15, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29368589

RESUMO

BACKGROUND: Preimplantation genetic diagnosis (PGD) is a powerful tool for preventing the transmission of Mendelian disorders from generation to generation. However, PGD only can identify monogenically inherited diseases, but not other potential monogenic pathologies. We aimed to use PGD to deliver a healthy baby without congenital FVII deficiency or other common Mendelian diseases in a couple in which both individuals carried a deleterious mutation in the F7 gene. METHODS: After both members of the couple were confirmed to be carriers of the F7 gene mutation by Sanger sequencing, expanded carrier screening (ECS) for 623 recessive inheritance diseases was performed to detect pathological mutations in other genes. PGD and preimplantational genetic screening (PGS) were employed to exclude monogenic disorders and aneuploidy for their embryos. RESULTS: ECS using targeted capture sequencing technology revealed that the couple carried the heterozygous disease-causative mutations c.3659C > T (p.Thr1220Ile) and c.3209G > A (p.Arg1070Gln) in the CFTR gene. After PGD and PGS, one of their embryos that was free of congenital FVII deficiency, cystic fibrosis (CF) and aneuploidy was transferred, resulting in the birth of a healthy 3200 g male infant. CONCLUSION: We successfully implemented PGD for congenital FVII deficiency and PGD after ECS to exclude CF for the first time to the best of our knowledge. Our work significantly improved the reproductive outcome for the couple and provides a clear example of the use of ECS combined with PGD to avoid the delivery of offspring affected not only by identified monogenically inherited diseases but also by other potential monogenic pathologies and aneuploidy.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Deficiência do Fator VII/diagnóstico , Deficiência do Fator VII/genética , Testes Genéticos , Diagnóstico Pré-Implantação , Aneuploidia , Fibrose Cística/diagnóstico , Fibrose Cística/genética , Fibrose Cística/prevenção & controle , Fator VII/genética , Fator VII/metabolismo , Deficiência do Fator VII/prevenção & controle , Feminino , Fertilização in vitro , Deleção de Genes , Genes Recessivos , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/prevenção & controle , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Linhagem , Gravidez , Resultado da Gravidez , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
19.
Biol Pharm Bull ; 41(8): 1291-1294, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30068880

RESUMO

Systems for delivering nucleic acids are now fundamental technologies for realizing personalized medicine. Among the various nucleic acid delivery systems that are currently available, lipid-nanoparticles (LNPs) that contain short interfering RNA (siRNA) have been extensively investigated for clinical applications. LNPs are generally prepared by an alcohol dilution method. In this method, it is necessary to remove the alcohol and then concentrate the LNP sample before they can be used. In this study, we report on the development of an "alcohol dilution-lyophilization method" for preparing siRNA-encapsulating LNPs. This method involves the use of a freeze-drying (lyophilization) method to remove the residual alcohol and to simultaneously concentrate the preparation. At first, the compositions of cryoprotectants and polyethylene glycol (PEG)-lipids that were used were optimized from the point of view of particle stabilization. A combination of sucrose and 1-(monomethoxy polyethyleneglycol5000)-2,3-dimyristoylglycerol (DMG-PEG5000) was found to have the most efficient cryoprotective activity for the LNPs. The knockdown efficiency of the LNP prepared by the alcohol dilution-lyophilization method was comparable to that of an LNP prepared by the conventional ultrafiltration method.


Assuntos
Composição de Medicamentos/métodos , Nanopartículas/química , RNA Interferente Pequeno/química , 1-Butanol , Animais , Colesterol/química , Crioprotetores/química , Fator VII/genética , Fator VII/metabolismo , Liofilização , Fígado/metabolismo , Masculino , Camundongos Endogâmicos ICR , Ácido Mirístico/química , Nanopartículas/administração & dosagem , Fosfatidilcolinas/química , Polietilenoglicóis/química , RNA Interferente Pequeno/administração & dosagem , Sacarose/química , Triglicerídeos/química , alfa-Tocoferol/química
20.
Angiogenesis ; 20(1): 85-96, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27807692

RESUMO

Identification of target molecules specific for angiogenic vascular endothelial cells (VEC), the inner layer of pathological neovasculature, is critical for discovery and development of neovascular-targeting therapy for angiogenesis-dependent human diseases, notably cancer, macular degeneration and endometriosis, in which vascular endothelial growth factor (VEGF) plays a central pathophysiological role. Using VEGF-stimulated vascular endothelial cells (VECs) isolated from microvessels, venous and arterial blood vessels as in vitro angiogenic models and unstimulated VECs as a quiescent VEC model, we examined the expression of tissue factor (TF), a membrane-bound receptor on the angiogenic VEC models compared with quiescent VEC controls. We found that TF is specifically expressed on angiogenic VECs in a time-dependent manner in microvessels, venous and arterial vessels. TF-targeted therapeutic agents, including factor VII (fVII)-IgG1 Fc and fVII-conjugated photosensitizer, can selectively bind angiogenic VECs, but not the quiescent VECs. Moreover, fVII-targeted photodynamic therapy can selectively and completely eradicate angiogenic VECs. We conclude that TF is an angiogenic-specific receptor and the target molecule for fVII-targeted therapeutics. This study supports clinical trials of TF-targeted therapeutics for the treatment of angiogenesis-dependent diseases such as cancer, macular degeneration and endometriosis.


Assuntos
Fator VII/metabolismo , Imunoterapia , Terapia de Alvo Molecular , Neovascularização Fisiológica , Fotoquimioterapia , Tromboplastina/metabolismo , Linhagem Celular , Células Endoteliais/metabolismo , Humanos , Ligação Proteica
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