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1.
Cell ; 153(1): 112-25, 2013 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-23477864

RESUMEN

Influenza A viruses are a major cause of mortality. Given the potential for future lethal pandemics, effective drugs are needed for the treatment of severe influenza such as that caused by H5N1 viruses. Using mediator lipidomics and bioactive lipid screen, we report that the omega-3 polyunsaturated fatty acid (PUFA)-derived lipid mediator protectin D1 (PD1) markedly attenuated influenza virus replication via RNA export machinery. Production of PD1 was suppressed during severe influenza and PD1 levels inversely correlated with the pathogenicity of H5N1 viruses. Suppression of PD1 was genetically mapped to 12/15-lipoxygenase activity. Importantly, PD1 treatment improved the survival and pathology of severe influenza in mice, even under conditions where known antiviral drugs fail to protect from death. These results identify the endogenous lipid mediator PD1 as an innate suppressor of influenza virus replication that protects against lethal influenza virus infection.


Asunto(s)
Transporte Activo de Núcleo Celular , Ácidos Docosahexaenoicos/inmunología , Subtipo H1N1 del Virus de la Influenza A/fisiología , Subtipo H5N1 del Virus de la Influenza A/fisiología , Infecciones por Orthomyxoviridae/inmunología , Replicación Viral , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Línea Celular , Ácidos Docosahexaenoicos/análisis , Ácidos Docosahexaenoicos/farmacología , Humanos , Ratones , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Infecciones por Orthomyxoviridae/virología , Replicación Viral/efectos de los fármacos
2.
Cell ; 141(1): 142-53, 2010 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-20371351

RESUMEN

Heart diseases are the most common causes of morbidity and death in humans. Using cardiac-specific RNAi-silencing in Drosophila, we knocked down 7061 evolutionarily conserved genes under conditions of stress. We present a first global roadmap of pathways potentially playing conserved roles in the cardiovascular system. One critical pathway identified was the CCR4-Not complex implicated in transcriptional and posttranscriptional regulatory mechanisms. Silencing of CCR4-Not components in adult Drosophila resulted in myofibrillar disarray and dilated cardiomyopathy. Heterozygous not3 knockout mice showed spontaneous impairment of cardiac contractility and increased susceptibility to heart failure. These heart defects were reversed via inhibition of HDACs, suggesting a mechanistic link to epigenetic chromatin remodeling. In humans, we show that a common NOT3 SNP correlates with altered cardiac QT intervals, a known cause of potentially lethal ventricular tachyarrhythmias. Thus, our functional genome-wide screen in Drosophila can identify candidates that directly translate into conserved mammalian genes involved in heart function.


Asunto(s)
Drosophila melanogaster/fisiología , Modelos Animales , Animales , Cardiomiopatías/genética , Cardiomiopatías/fisiopatología , Drosophila melanogaster/embriología , Drosophila melanogaster/genética , Femenino , Estudio de Asociación del Genoma Completo , Corazón/embriología , Corazón/fisiología , Humanos , Masculino , Ratones , Ratones Noqueados , Regiones Promotoras Genéticas , Interferencia de ARN
3.
Genes Cells ; 28(8): 573-584, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37248626

RESUMEN

Tumor-derived G-CSF is a well-known factor to aggravate disease progression in various types of cancers. In this study, we investigated a role of G-CSF in squamous cell carcinoma (SCC). High expression of G-CSF in the tumor tissues of esophageal SCC (ESCC) patients correlated with poor prognosis. Murine SCC NR-S1M cells produce considerable amount of G-CSF, which expression is correlated with its metastatic potentials. Deletion of G-CSF in NR-S1M cells mitigated tumor growth and metastasis to lymph node and lung of subcutaneous NR-S1M tumors in the mice. Mechanistically, G-CSF enhanced cell proliferation in autocrine manner in vitro, whereas in NR-S1M tumor-bearing mice, accumulation of plasma G-CSF was associated with expansion of peripheral neutrophils, which led to a decreased proportion of CD8+ T cells. Antibody depletion of neutrophils restored the number of CD8+ T cells and modestly suppressed tumor outgrowth, albeit no changes in distant metastasis. We propose that G-CSF produced by NR-S1M cells facilitates tumor progression in mice through bi-functional effects to promote neutrophil recruitment and tumor cell proliferation, which may render poor prognosis to the ESCC patients with high G-CSF expression.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Animales , Ratones , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Factor Estimulante de Colonias de Granulocitos/metabolismo , Infiltración Neutrófila , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas/genética , Proliferación Celular , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica
4.
Genes Dev ; 30(20): 2310-2324, 2016 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-27807034

RESUMEN

Transcription factor EBF1 (early B-cell factor 1) regulates early B-cell differentiation by poising or activating lineage-specific genes and repressing genes associated with alternative cell fates. To identify proteins that regulate the diverse functions of EBF1, we used SILAC (stable isotope labeling by amino acids in cell culture)-based mass spectrometry of proteins associated with endogenous EBF1 in pro-B cells. This analysis identified most components of the multifunctional CCR4-NOT complex, which regulates transcription and mRNA degradation. CNOT3 interacts with EBF1, and we identified histidine 240 in EBF1 as a critical residue for this interaction. Complementation of Ebf1-/- progenitors with EBF1H240A revealed a partial block of pro-B-cell differentiation and altered expression of specific EBF1 target genes that show either reduced transcription or increased mRNA stability. Most deregulated EBF1 target genes show normal occupancy by EBF1H240A, but we also detected genes with altered occupancy, suggesting that the CCR4-NOT complex affects multiple activities of EBF1. Mice with conditional Cnot3 inactivation recapitulate the block of early B-cell differentiation, which we found to be associated with an impaired autoregulation of Ebf1 and reduced expression of pre-B-cell receptor components. Thus, the interaction of the CCR4-NOT complex with EBF1 diversifies the function of EBF1 in a context-dependent manner and may coordinate transcriptional and post-transcriptional gene regulation.


Asunto(s)
Linfocitos B/fisiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Regulación de la Expresión Génica/genética , Proteínas de Homeodominio/metabolismo , Linfopoyesis/genética , Proteínas Nucleares/metabolismo , Estabilidad del ARN/genética , Factores de Transcripción/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular/genética , Silenciador del Gen , Células HEK293 , Proteínas de Homeodominio/genética , Humanos , Ratones , Chaperonas Moleculares/genética , Mutación , Proteínas Nucleares/genética , Unión Proteica , Factores de Transcripción/genética , Transgenes
5.
Biochem Biophys Res Commun ; 647: 72-79, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-36731336

RESUMEN

Apelin (APL), an endogenous ligand for APJ, has been reported to be upregulated in a murine model of acute colitis induced by sodium dextran sulfate, as well as inflammatory bowel diseases (IBD) in humans. However, the mechanisms and functions of APL/APJ axis in the pathogenesis of IBD are unclear. We herein analyzed CD4+ T cells to determine the functions of APL in a murine model of chronic colitis induced in Rag deficient mice (Rag-/-). In colonic tissues of wild-type mice (WT), we found that APL was expressed especially in the lamina propria lymphocytes, where CD4+ T cells are dominant, rather than the epithelial cells. Unexpectedly, the APL expression was rather downregulated in the colonic tissue of the chronic colitis group compared to the control groups (Rag-/- before colitis induction and WT). The APL expression was downregulated when naïve T cells were differentiated into effecter T cells. A lack of APL resulted in decreased naïve T cells and increased effecter T cells in secondary lymphoid organs. A synthetic APL peptide, [Pyr1]-APL-13, increased IL-10 and decreased IFN-γ productions by effecter T cells. Administration of [Pyr1]-APL-13 improved survival rate in association with lessened colitis severity and decreased pro-inflammatory cytokine production. This is the first report showing immunological function of APL specifically on T cells, and these results indicate that APL/APJ axis may be a novel therapeutic target for IBD.


Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Ratones , Humanos , Animales , Linfocitos T/metabolismo , Apelina/metabolismo , Modelos Animales de Enfermedad , Colitis/patología , Enfermedades Inflamatorias del Intestino/metabolismo , Sulfato de Dextran , Ratones Endogámicos C57BL , Linfocitos T CD4-Positivos
6.
Cell ; 133(2): 235-49, 2008 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-18423196

RESUMEN

Multiple lung pathogens such as chemical agents, H5N1 avian flu, or SARS cause high lethality due to acute respiratory distress syndrome. Here we report that Toll-like receptor 4 (TLR4) mutant mice display natural resistance to acid-induced acute lung injury (ALI). We show that TLR4-TRIF-TRAF6 signaling is a key disease pathway that controls the severity of ALI. The oxidized phospholipid (OxPL) OxPAPC was identified to induce lung injury and cytokine production by lung macrophages via TLR4-TRIF. We observed OxPL production in the lungs of humans and animals infected with SARS, Anthrax, or H5N1. Pulmonary challenge with an inactivated H5N1 avian influenza virus rapidly induces ALI and OxPL formation in mice. Loss of TLR4 or TRIF expression protects mice from H5N1-induced ALI. Moreover, deletion of ncf1, which controls ROS production, improves the severity of H5N1-mediated ALI. Our data identify oxidative stress and innate immunity as key lung injury pathways that control the severity of ALI.


Asunto(s)
Estrés Oxidativo , Síndrome de Dificultad Respiratoria/metabolismo , Receptor Toll-Like 4/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Animales , Humanos , Gripe Humana/metabolismo , Interleucina-6/metabolismo , Pulmón , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasas/metabolismo , FN-kappa B/metabolismo , Infecciones por Orthomyxoviridae/metabolismo , Fosfolípidos/metabolismo , Síndrome Respiratorio Agudo Grave/metabolismo , Transducción de Señal
7.
Genes Cells ; 25(8): 547-561, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32449584

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is one of the most fatal types of malignant tumors worldwide. Epitranscriptome, such as N6 -methyladenosine (m6 A) of mRNA, is an abundant post-transcriptional mRNA modification and has been recently implicated to play roles in several cancers, whereas the significance of m6 A modifications is virtually unknown in ESCC. Analysis of tissue microarray of the tumors in 177 ESCC patients showed that higher expression of m6 A demethylase ALKBH5 correlated with poor prognosis and that ALKBH5 was an independent prognostic factor of the survival of patients. There was no correlation between the other demethylase FTO and prognosis. siRNA knockdown of ALKBH5 but not FTO significantly suppressed proliferation and migration of human ESCC cells. ALKBH5 knockdown delayed progression of cell cycle and accumulated the cells to G0/G1 phase. Mechanistically, expression of CDKN1A (p21) was significantly up-regulated in ALKBH5-depleted cells, and m6 A modification and stability of CDKN1A mRNA were increased by ALKBH5 knockdown. Furthermore, depletion of ALKBH5 substantially suppressed tumor growth of ESCC cells subcutaneously transplanted in BALB/c nude mice. Collectively, we identify ALKBH5 as the first m6 A demethylase that accelerates cell cycle progression and promotes cell proliferation of ESCC cells, which is associated with poor prognosis of ESCC patients.


Asunto(s)
Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Adulto , Anciano , Enzimas AlkB/metabolismo , Desmetilasa de ARN, Homólogo 5 de AlkB/genética , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Animales , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Progresión de la Enfermedad , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Pronóstico , Estabilidad del ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
8.
FASEB J ; 34(9): 12492-12501, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32721046

RESUMEN

Lipid mediators play important roles in regulating inflammatory responses and tissue homeostasis. Since 12/15-lipoxygenase (12/15-LOX)-derived lipid mediators such as lipoxin A4 (LXA4 ) and protectin D1 (PD1) protect against corneal epithelial cell damage, the major cell types that express 12/15-LOX and contribute to the corneal wound healing process are of particular interest. Here, we found that eosinophils were the major cell type expressing 12/15-LOX during the corneal wound healing process. Eosinophils were recruited into the conjunctiva after corneal epithelium wounding, and eosinophil-deficient and/or eosinophil-specific 12/15-LOX knockout mice showed delayed corneal wound healing compared with wild-type mice. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based mediator lipidomics revealed that a series of 12/15-LOX-derived mediators were significantly decreased in eosinophil-deficient mice and topical application of 17-hydroxydocosahexaenoic acid (17-HDoHE), a major 12/15-LOX-derived product, restored the phenotype. These results indicate that 12/15-LOX-expressing eosinophils, by locally producing pro-resolving mediators, significantly contribute to the corneal wound healing process in the eye.


Asunto(s)
Araquidonato 12-Lipooxigenasa/fisiología , Araquidonato 15-Lipooxigenasa/fisiología , Lesiones de la Cornea/patología , Eosinófilos/citología , Cicatrización de Heridas , Animales , Córnea/patología , Eosinófilos/enzimología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
9.
RNA Biol ; 17(3): 403-416, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31924127

RESUMEN

Shortening of mRNA poly(A) tails (deadenylation) to trigger their decay is mediated mainly by the CCR4-NOT deadenylase complex. While four catalytic subunits (CNOT6, 6L 7, and 8) have been identified in the mammalian CCR4-NOT complex, their individual biological roles are not fully understood. In this study, we addressed the contribution of CNOT7/8 to viability of primary mouse embryonic fibroblasts (MEFs). We found that MEFs lacking CNOT7/8 expression [Cnot7/8-double knockout (dKO) MEFs] undergo cell death, whereas MEFs lacking CNOT6/6L expression (Cnot6/6l-dKO MEFs) remain viable. Co-immunoprecipitation analyses showed that CNOT6/6L are also absent from the CCR4-NOT complex in Cnot7/8-dKO MEFs. In contrast, either CNOT7 or CNOT8 still interacts with other subunits in the CCR4-NOT complex in Cnot6/6l-dKO MEFs. Exogenous expression of a CNOT7 mutant lacking catalytic activity in Cnot7/8-dKO MEFs cannot recover cell viability, even though CNOT6/6L exists to some extent in the CCR4-NOT complex, confirming that CNOT7/8 is essential for viability. Bulk poly(A) tail analysis revealed that mRNAs with longer poly(A) tails are more numerous in Cnot7/8-dKO MEFs than in Cnot6/6l-dKO MEFs. Consistent with elongated poly(A) tails, more mRNAs are upregulated and stabilized in Cnot7/8-dKO MEFs than in Cnot6/6l-dKO MEFs. Importantly, Cnot6/6l-dKO mice are viable and grow normally to adulthood. Taken together, the CNOT7/8 catalytic subunits are essential for deadenylation, which is necessary to maintain cell viability, whereas CNOT6/6L are not.


Asunto(s)
Exorribonucleasas/metabolismo , ARN Mensajero/metabolismo , Receptores CCR4/metabolismo , Proteínas Represoras/metabolismo , Animales , Supervivencia Celular/genética , Exorribonucleasas/genética , Femenino , Fibroblastos/citología , Fibroblastos/fisiología , Masculino , Ratones Noqueados , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Poli A/genética , Poli A/metabolismo , Subunidades de Proteína , Estabilidad del ARN , ARN Mensajero/genética , Receptores CCR4/genética , Proteínas Represoras/genética
10.
Chembiochem ; 20(12): 1563-1568, 2019 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-30734978

RESUMEN

Malformin A1 (MA1) is a fungus-produced cyclic pentapeptide. MA1 exhibits teratogenicity to plants, fibrinolysis-enhancing activity, and cytotoxicity to mammalian cells. To clarify the cytotoxic mechanism of MA1, we screened for the genes involved in the cytotoxicity of MA1 in monocytoid U937 cells by using a CRISPR/Cas9-based genome-wide knockout library. Screening was performed by positive selection for cells that were resistant to MA1 treatment, and single guide RNAs (sgRNAs) integrated into MA1-resistant cells were analyzed by high-throughput sequencing. As a result of the evaluation of sgRNAs that were enriched in MA1-resistant cells, SQLE, which encodes squalene epoxidase, was identified as a candidate gene. SQLE-depleted U937 cells were viable in the presence of MA1, and squalene epoxidase inhibitor conferred MA1 resistance to wild-type cells. These results indicate that squalene epoxidase is implicated in the cytotoxicity of MA1. This finding represents a new insight into applications of MA1 for treating ischemic diseases.


Asunto(s)
Péptidos Cíclicos/farmacología , Escualeno-Monooxigenasa/genética , Aspergillus niger/metabolismo , Sistemas CRISPR-Cas , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Humanos , ARN Guía de Kinetoplastida/genética , Escualeno-Monooxigenasa/metabolismo , Células U937
11.
Int J Mol Sci ; 20(2)2019 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-30634441

RESUMEN

Apelin is an inotropic and cardioprotective peptide that exhibits beneficial effects through activation of the APJ receptor in the pathology of cardiovascular diseases. Apelin induces the expression of angiotensin-converting enzyme 2 (ACE2) in failing hearts, thereby improving heart function in an angiotensin 1⁻7-dependent manner. Whether apelin antagonizes the over-activation of the renin⁻angiotensin system in the heart remains elusive. In this study we show that the detrimental effects of angiotensin II (Ang II) were exacerbated in the hearts of aged apelin-gene-deficient mice. Ang II-mediated cardiac dysfunction and hypertrophy were augmented in apelin knockout mice. The loss of apelin increased the ratio of angiotensin-converting enzyme (ACE) to ACE2 expression in the Ang II-stressed hearts, and Ang II-induced cardiac fibrosis was markedly enhanced in apelin knockout mice. mRNA expression of pro-fibrotic genes, such as transforming growth-factor beta (TGF-ß) signaling, were significantly upregulated in apelin knockout hearts. Consistently, treatment with the ACE-inhibitor Captopril decreased cardiac contractility in apelin knockout mice. In vitro, apelin ameliorated Ang II-induced TGF-ß expression in primary cardiomyocytes, accompanied with reduced hypertrophy. These results provide direct evidence that endogenous apelin plays a crucial role in suppressing Ang II-induced cardiac dysfunction and pathological remodeling.


Asunto(s)
Angiotensina II/metabolismo , Apelina/deficiencia , Disfunción Ventricular/genética , Remodelación Ventricular/genética , Enzima Convertidora de Angiotensina 2 , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Biopsia , Cardiomegalia/genética , Cardiomegalia/metabolismo , Cardiomegalia/patología , Cardiomegalia/fisiopatología , Modelos Animales de Enfermedad , Ecocardiografía , Fibrosis , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Hipertensión/genética , Hipertensión/metabolismo , Hipertensión/patología , Hipertensión/fisiopatología , Ratones , Ratones Noqueados , Contracción Miocárdica/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Peptidil-Dipeptidasa A/metabolismo
12.
Int J Mol Sci ; 20(21)2019 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-31652943

RESUMEN

Shortening of poly(A) tails triggers mRNA degradation; hence, mRNA deadenylation regulates many biological events. In the present study, we generated mice lacking the Cnot1 gene, which encodes an essential scaffold subunit of the CCR4-NOT deadenylase complex in adipose tissues (Cnot1-AKO mice) and we examined the role of CCR4-NOT in adipocyte function. Cnot1-AKO mice showed reduced masses of white adipose tissue (WAT) and brown adipose tissue (BAT), indicating abnormal organization and function of those tissues. Indeed, Cnot1-AKO mice showed hyperinsulinemia, hyperglycemia, insulin resistance, and glucose intolerance and they could not maintain a normal body temperature during cold exposure. Muscle-like fibrous material appeared in both WAT and BAT of Cnot1-AKO mice, suggesting the acquisition of non-adipose tissue characteristics. Gene expression analysis using RNA-sequencing (RNA-seq) showed that the levels of adipose tissue-related mRNAs, including those of metabolic genes, decreased, whereas the levels of inflammatory response-related mRNAs increased. These data suggest that the CCR4-NOT complex ensures proper adipose tissue function by maintaining adipocyte-specific mRNAs at appropriate levels and by simultaneously suppressing mRNAs that would impair adipocyte function if overexpressed.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Factores de Transcripción/genética , Adipocitos/citología , Adipocitos/metabolismo , Tejido Adiposo Pardo/patología , Tejido Adiposo Blanco/patología , Animales , Temperatura Corporal , Células Cultivadas , Regulación de la Expresión Génica , Hiperglucemia/etiología , Hiperglucemia/metabolismo , Hiperinsulinismo/etiología , Hiperinsulinismo/metabolismo , Metabolismo de los Lípidos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Mensajero/metabolismo , Factores de Transcripción/deficiencia
13.
Nature ; 487(7408): 477-81, 2012 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-22837003

RESUMEN

Malnutrition affects up to one billion people in the world and is a major cause of mortality. In many cases, malnutrition is associated with diarrhoea and intestinal inflammation, further contributing to morbidity and death. The mechanisms by which unbalanced dietary nutrients affect intestinal homeostasis are largely unknown. Here we report that deficiency in murine angiotensin I converting enzyme (peptidyl-dipeptidase A) 2 (Ace2), which encodes a key regulatory enzyme of the renin-angiotensin system (RAS), results in highly increased susceptibility to intestinal inflammation induced by epithelial damage. The RAS is known to be involved in acute lung failure, cardiovascular functions and SARS infections. Mechanistically, ACE2 has a RAS-independent function, regulating intestinal amino acid homeostasis, expression of antimicrobial peptides, and the ecology of the gut microbiome. Transplantation of the altered microbiota from Ace2 mutant mice into germ-free wild-type hosts was able to transmit the increased propensity to develop severe colitis. ACE2-dependent changes in epithelial immunity and the gut microbiota can be directly regulated by the dietary amino acid tryptophan. Our results identify ACE2 as a key regulator of dietary amino acid homeostasis, innate immunity, gut microbial ecology, and transmissible susceptibility to colitis. These results provide a molecular explanation for how amino acid malnutrition can cause intestinal inflammation and diarrhoea.


Asunto(s)
Colitis/etiología , Colitis/microbiología , Intestinos/microbiología , Desnutrición/complicaciones , Metagenoma , Peptidil-Dipeptidasa A/metabolismo , Triptófano/metabolismo , Enzima Convertidora de Angiotensina 2 , Animales , Biocatálisis , Colitis/tratamiento farmacológico , Colitis/patología , Sulfato de Dextran , Diarrea/complicaciones , Proteínas en la Dieta/metabolismo , Proteínas en la Dieta/farmacología , Femenino , Eliminación de Gen , Predisposición Genética a la Enfermedad , Vida Libre de Gérmenes , Homeostasis , Inmunidad Innata , Intestinos/patología , Masculino , Desnutrición/metabolismo , Ratones , Modelos Biológicos , Niacinamida/metabolismo , Niacinamida/farmacología , Niacinamida/uso terapéutico , Peptidil-Dipeptidasa A/deficiencia , Peptidil-Dipeptidasa A/genética , Sistema Renina-Angiotensina/fisiología , Serina-Treonina Quinasas TOR/metabolismo , Ácido Trinitrobencenosulfónico , Triptófano/farmacología , Triptófano/uso terapéutico
14.
Am J Respir Cell Mol Biol ; 56(2): 179-190, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27668315

RESUMEN

For acute respiratory distress syndrome (ARDS), mechanical ventilation (MV) is a life-saving intervention without alternative; however, MV can cause ventilator-induced lung injury. Reactive oxygen species (ROS) play important roles in the pathogenesis of both ARDS and ventilator-induced lung injury. Lecithinized superoxide dismutase (PC-SOD) overcomes the limitations of superoxide dismutase such as low tissue affinity and low stability in plasma. In this study, we examined the effect of PC-SOD on tissue injury, edema, and inflammation in the lung and other organs of mice subjected to cecal ligation and puncture (CLP), LPS administration, or MV. The severity of the lung injury was assessed on the basis of vascular permeability, histopathologic evaluation, and lung mechanics. Intravenous PC-SOD administration (the first administered just before CLP) increased the survival rate and decreased vascular permeability in mice subjected to CLP. PC-SOD, but not dexamethasone or sivelestat sodium hydrate (sivelestat), suppressed CLP-induced kidney injury and systemic inflammation. PC-SOD also suppressed vascular permeability, tissue injury, and inflammation in the lung induced by LPS administration. Moreover, PC-SOD, but not dexamethasone or sivelestat, suppressed vascular permeability, edema, tissue injury, and mechanical alterations in the lung induced by MV. In vivo imaging analysis of ROS revealed that CLP, LPS administration, and MV increased the level of ROS and that this increase was suppressed by PC-SOD. The results of this study thus suggest that, on the basis of its ROS-reducing properties, intravenous administration of PC-SOD may be beneficial for patients at high risk of developing ARDS.


Asunto(s)
Fosfatidilcolinas/uso terapéutico , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/prevención & control , Superóxido Dismutasa/uso terapéutico , Animales , Ciego/patología , Dexametasona/farmacología , Modelos Animales de Enfermedad , Glicina/análogos & derivados , Glicina/farmacología , Glicina/uso terapéutico , Ligadura , Lipopolisacáridos , Lesión Pulmonar/complicaciones , Lesión Pulmonar/tratamiento farmacológico , Lesión Pulmonar/patología , Masculino , Ratones , Ratones Endogámicos ICR , Insuficiencia Multiorgánica/complicaciones , Insuficiencia Multiorgánica/patología , Fosfatidilcolinas/farmacología , Punciones , Especies Reactivas de Oxígeno/metabolismo , Respiración Artificial , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Superóxido Dismutasa/farmacología
15.
Bioorg Med Chem Lett ; 26(21): 5267-5271, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27680590

RESUMEN

The formation of blood clots in blood vessels causes severe ischemic diseases such as cerebral infarction and myocardial infarction. While searching for microbial products that increase fibrinolytic activity using an in vitro fibrin degradation assay, we found malformin A1, a disulfide form of cyclo(-d-Cys-d-Cys-l-Val-d-Leu-l-Ile-), as an active compound. In this study, we synthesized malformin derivatives using a solid-phase peptide synthesis method and evaluated their fibrinolytic activity and cytotoxicity. Reduction of the disulfide bond and linearization of the cyclic peptide frame decreased the pro-fibrinolytic activity. Substitution of a branched-chain amino acid with lysine resulted in loss of activity. However, protection of the amino group in the lysine derivatives by the tert-butoxycarbonyl (Boc) group rescued the inactivity. Furthermore, the phenylalanine derivatives also exhibited a similar pro-fibrinolytic effect compared to malformin A1. These results suggest that the disulfide bond, the cyclic peptide frame, and the bulky hydrophobic side chains play a crucial role in the pro-fibrinolytic activity of malformin. The effective dose of the active derivatives for the in vitro fibrin degradation showed similar ranges (1-5µM), while the order of cytotoxic potency for the active derivatives was as follows: Phe-derivatives>BocLys-derivatives>malformin A1>reduced form. These results showed no correlation between pro-fibrinolytic activity and cytotoxicity, suggesting the possibility of the synthesis for non-toxic malformin derivatives possessing the activity.


Asunto(s)
Fibrinólisis/efectos de los fármacos , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Humanos , Concentración 50 Inhibidora , Análisis Espectral/métodos , Relación Estructura-Actividad , Células U937
16.
Part Fibre Toxicol ; 12: 4, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-25890286

RESUMEN

BACKGROUND: Nanoparticles have become a key technology in multiple industries. However, there are growing reports of the toxicity of nanomaterials to humans. In particular, nanomaterials have been linked to lung diseases. The molecular mechanisms of nanoparticle toxicity are largely unexplored. METHODS: Acute lung injury was induced in wild-type mice and angiotensin-coverting enzyme 2 (ACE2) knockout mice by the intratracheal instillation of cationic polyamidoamine dendrimer (PAMAM) nanoparticles. For rescue experiments, losartan (15 mg/kg in PBS) was injected intraperitoneally 30 min before nanoparticle administration. RESULTS: Some PAMAM nanoparticles, but not anionic PAMAM nanoparticles or carbon nanotubes, triggered acute lung failure in mice. Mechanistically, cationic nanoparticles can directly bind ACE2, decrease its activity and down-regulate its expression level in lung tissue, resulting in deregulation of the renin-angiotensin system. Gene inactivation of Ace2 can exacerbate lung injury. Importantly, the administration of losartan, which is an angiotensin II type I receptor antagonist, can ameliorate PAMAM nanoparticle-induced lung injury. CONCLUSIONS: Our data provide molecular insight into PAMAM nanoparticle-induced lung injury and suggest potential therapeutic and screening strategies to address the safety of nanomaterials.


Asunto(s)
Lesión Pulmonar Aguda/inducido químicamente , Dendrímeros/toxicidad , Nanopartículas/toxicidad , Peptidil-Dipeptidasa A/metabolismo , Lesión Pulmonar Aguda/metabolismo , Lesión Pulmonar Aguda/patología , Enzima Convertidora de Angiotensina 2 , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Cationes , Dendrímeros/administración & dosificación , Dendrímeros/química , Regulación hacia Abajo , Instilación de Medicamentos , Losartán/farmacología , Ratones Endogámicos C57BL , Ratones Noqueados , Nanopartículas/administración & dosificación , Nanopartículas/química , Peptidil-Dipeptidasa A/genética , Unión Proteica , Análisis de Supervivencia
17.
Am J Respir Crit Care Med ; 187(1): 65-77, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23144331

RESUMEN

RATIONALE: Patients who developed acute respiratory distress syndrome (ARDS) after infection with severe respiratory viruses (e.g., severe acute respiratory syndrome-coronavirus, H5N1 avian influenza virus), exhibited unusually high levels of CXCL10, which belongs to the non-ELR (glutamic-leucine-arginine) CXC chemokine superfamily. CXCL10 may not be a bystander to the severe virus infection but may directly contribute to the pathogenesis of neutrophil-mediated, excessive pulmonary inflammation. OBJECTIVES: We investigated the contribution of CXCL10 and its receptor CXCR3 axis to the pathogenesis of ARDS with nonviral and viral origins. METHODS: We induced nonviral ARDS by acid aspiration and viral ARDS by intratracheal influenza virus infection in wild-type mice and mice deficient in CXCL10, CXCR3, IFNAR1 (IFN-α/ß receptor 1), or TIR domain-containing adaptor inducing IFN-ß (TRIF). MEASUREMENTS AND MAIN RESULTS: We found that the mice lacking CXCL10 or CXCR3 demonstrated improved severity and survival of nonviral and viral ARDS, whereas mice that lack IFNAR1 did not control the severity of ARDS in vivo. The increased levels of CXCL10 in lungs with ARDS originate to a large extent from infiltrated pulmonary neutrophils, which express a unique CXCR3 receptor via TRIF. CXCL10-CXCR3 acts in an autocrine fashion on the oxidative burst and chemotaxis in the inflamed neutrophils, leading to fulminant pulmonary inflammation. CONCLUSIONS: CXCL10-CXCR3 signaling appears to be a critical factor for the exacerbation of the pathology of ARDS. Thus, the CXCL10-CXCR3 axis could represent a prime therapeutic target in the treatment of the acute phase of ARDS of nonviral and viral origins.


Asunto(s)
Quimiocina CXCL10/fisiología , Lesión Pulmonar/fisiopatología , Neutrófilos/fisiología , Infecciones por Orthomyxoviridae/fisiopatología , Receptores CXCR3/fisiología , Síndrome de Dificultad Respiratoria/fisiopatología , Anciano , Anciano de 80 o más Años , Animales , Quimiocina CXCL10/efectos de los fármacos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Subtipo H5N1 del Virus de la Influenza A , Lesión Pulmonar/inmunología , Lesión Pulmonar/virología , Masculino , Ratones , Ratones Endogámicos , Persona de Mediana Edad , Neutrófilos/inmunología , Infecciones por Orthomyxoviridae/inmunología , Análisis por Matrices de Proteínas , Ratas , Ratas Sprague-Dawley , Receptores CXCR3/efectos de los fármacos , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Síndrome de Dificultad Respiratoria/inmunología , Síndrome de Dificultad Respiratoria/virología
18.
Nat Struct Mol Biol ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773334

RESUMEN

Eukaryotic translation initiation factor (eIF)4A-a DEAD-box RNA-binding protein-plays an essential role in translation initiation. Recent reports have suggested helicase-dependent and helicase-independent functions for eIF4A, but the multifaceted roles of eIF4A have not been fully explored. Here we show that eIF4A1 enhances translational repression during the inhibition of mechanistic target of rapamycin complex 1 (mTORC1), an essential kinase complex controlling cell proliferation. RNA pulldown followed by sequencing revealed that eIF4A1 preferentially binds to mRNAs containing terminal oligopyrimidine (TOP) motifs, whose translation is rapidly repressed upon mTORC1 inhibition. This selective interaction depends on a La-related RNA-binding protein, LARP1. Ribosome profiling revealed that deletion of EIF4A1 attenuated the translational repression of TOP mRNAs upon mTORC1 inactivation. Moreover, eIF4A1 increases the interaction between TOP mRNAs and LARP1 and, thus, ensures stronger translational repression upon mTORC1 inhibition. Our data show the multimodality of eIF4A1 in modulating protein synthesis through an inhibitory binding partner and provide a unique example of the repressive role of a universal translational activator.

19.
J Exp Clin Cancer Res ; 43(1): 138, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38715057

RESUMEN

BACKGROUND: Although immune checkpoint blockade (ICB) therapy has proven to be extremely effective at managing certain cancers, its efficacy in treating pancreatic ductal adenocarcinoma (PDAC) has been limited. Therefore, enhancing the effect of ICB could improve the prognosis of PDAC. In this study, we focused on the histamine receptor H1 (HRH1) and investigated its impact on ICB therapy for PDAC. METHODS: We assessed HRH1 expression in pancreatic cancer cell (PCC) specimens from PDAC patients through public data analysis and immunohistochemical (IHC) staining. The impact of HRH1 in PCCs was evaluated using HRH1 antagonists and small hairpin RNA (shRNA). Techniques including Western blot, flow cytometry, quantitative reverse transcription polymerase chain reaction (RT-PCR), and microarray analyses were performed to identify the relationships between HRH1 and major histocompatibility complex class I (MHC-I) expression in cancer cells. We combined HRH1 antagonism or knockdown with anti-programmed death receptor 1 (αPD-1) therapy in orthotopic models, employing IHC, immunofluorescence, and hematoxylin and eosin staining for assessment. RESULTS: HRH1 expression in cancer cells was negatively correlated with HLA-ABC expression, CD8+ T cells, and cytotoxic CD8+ T cells. Our findings indicate that HRH1 blockade upregulates MHC-I expression in PCCs via cholesterol biosynthesis signaling. In the orthotopic model, the combined inhibition of HRH1 and αPD-1 blockade enhanced cytotoxic CD8+ T cell penetration and efficacy, overcoming resistance to ICB therapy. CONCLUSIONS: HRH1 plays an immunosuppressive role in cancer cells. Consequently, HRH1 intervention may be a promising method to amplify the responsiveness of PDAC to immunotherapy.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Ratones , Animales , Receptores Histamínicos H1/metabolismo , Receptores Histamínicos H1/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Línea Celular Tumoral , Femenino , Antagonistas de los Receptores Histamínicos H1/farmacología , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Masculino
20.
Circ J ; 77(2): 301-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23328447

RESUMEN

Angiotensin-converting enzyme 2 (ACE2) is a negative regulator of the renin-angiotensin system, and functions as the key SARS coronavirus receptor and stabilizer of neutral amino acid transporters. ACE2 catalyzes the conversion of angiotensin II to angiotensin 1-7, thereby counterbalancing ACE activity. Accumulating evidence indicates that the enzymatic activity of ACE2 has a protective role in cardiovascular diseases. Loss of ACE2 can be detrimental, as it leads to functional deterioration of the heart and progression of cardiac, renal, and vascular pathologies. Recombinant soluble human ACE2 protein has been demonstrated to exhibit beneficial effects in various animal models, including cardiovascular diseases. ACE2 is a multifunctional enzyme and thus potentially acts on other vasoactive peptides, such as Apelin, a vital regulator of blood pressure and myocardium contractility. In addition, ACE2 is structurally a chimeric protein that has emerged from the duplication of 2 genes: homology with ACE at the carboxypeptidase domain and homology with Collectrin in the transmembrane C-terminal domain. ACE2 has been implicated in the pathology of Hartnup's disease, a disorder of amino acid homeostasis, and, via its function in amino acid transport, it has been recently revealed that ACE2 controls intestinal inflammation and diarrhea, thus regulating the gut microbiome. This review summarizes and discusses the structure and multiple functions of ACE2 and the relevance of this key enzyme in disease pathogenesis.


Asunto(s)
Enfermedades Cardiovasculares/enzimología , Enfermedades Cardiovasculares/fisiopatología , Peptidil-Dipeptidasa A/fisiología , Enzima Convertidora de Angiotensina 2 , Animales , Humanos , Ratones , Ratones Noqueados , Peptidil-Dipeptidasa A/química , Estructura Terciaria de Proteína/fisiología
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