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1.
Hepatology ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38385945

RESUMO

BACKGROUND AND AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses a broad and continuous spectrum of liver diseases ranging from fatty liver to steatohepatitis. The intricate interactions of genetic, epigenetic, and environmental factors in the development and progression of MASLD remain elusive. Here, we aimed to achieve an integrative understanding of the genomic and transcriptomic alterations throughout the progression of MASLD. APPROACH AND RESULTS: RNA-Seq profiling (n = 146) and whole-exome sequencing (n = 132) of MASLD liver tissue samples identified 3 transcriptomic subtypes (G1-G3) of MASLD, which were characterized by stepwise pathological and molecular progression of the disease. Macrophage-driven inflammatory activities were identified as a key feature for differentiating these subtypes. This subtype-discriminating macrophage interplay was significantly associated with both the expression and genetic variation of the dsDNA sensor IFI16 (rs6940, A>T, T779S), establishing it as a fundamental molecular factor in MASLD progression. The in vitro dsDNA-IFI16 binding experiments and structural modeling revealed that the IFI16 variant exhibited increased stability and stronger dsDNA binding affinity compared to the wild-type. Further downstream investigation suggested that the IFI16 variant exacerbated DNA sensing-mediated inflammatory signals through mitochondrial dysfunction-related signaling of the IFI16-PYCARD-CASP1 pathway. CONCLUSIONS: This study unveils a comprehensive understanding of MASLD progression through transcriptomic classification, highlighting the crucial roles of IFI16 variants. Targeting the IFI16-PYCARD-CASP1 pathway may pave the way for the development of novel diagnostics and therapeutics for MASLD.

2.
Biochem Biophys Res Commun ; 654: 94-101, 2023 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-36898229

RESUMO

The human cytomegalovirus (HCMV)-encoded US12 gene family is a group of ten predicted seven-transmembrane domain proteins that are structurally similar to G-protein-coupled receptors or transmembrane Bax inhibitor-1 motif-containing proteins; however, the roles of US12 family proteins in virus-host interactions remain to be discovered. Here, we suggest a new function of the US12 protein in regulating cellular autophagy. US12 is predominantly located to the lysosome and interacts with the lysosomal membrane protein 2 (LAMP2). A liquid chromatography-mass spectrometry (MS)/MS-based targeted proteomics analysis shows that US12 is tightly correlated with autophagy. US12 induces autophagy via upregulating ULK1 phosphorylation and subsequent LC3-II conversion, thereby accelerating autophagic flux. Moreover, HeLa cells overexpressing US12 displays intense LC3-specific staining and autolysosome formation even under nutrient-sufficient conditions. Furthermore, the physical interaction of p62/SQSTM1 with US12 is involved in the resistance to the degradation of p62/SQSTM1 by autophagy, despite the induction of both autolysosome formation and autophagic flux. Although the effect of US12 expression in HCMV infection on autophagy remains undetermined, these findings provide new insights into the viral drivers of host autophagy during HCMV evolution and pathogenesis.


Assuntos
Citomegalovirus , Proteínas Virais , Humanos , Citomegalovirus/genética , Proteínas Virais/metabolismo , Células HeLa , Proteína Sequestossoma-1/metabolismo , Proteínas de Membrana/metabolismo , Autofagia/genética
3.
Gut ; 70(12): 2249-2260, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33558271

RESUMO

OBJECTIVE: Dysfunctional resolution of intestinal inflammation and altered mucosal healing are essential features in the pathogenesis of inflammatory bowel disease (IBD). Intestinal macrophages are vital in the process of inflammation resolution, but the mechanisms underlying their mucosal healing capacity remain elusive. DESIGN: We investigated the role of the prostaglandin E2 (PGE2) receptor PTGER4 on the differentiation of intestinal macrophages in patients with IBD and mouse models of intestinal inflammation. We studied mucosal healing and intestinal epithelial barrier regeneration in Csf1r-iCre Ptger4fl/fl mice during dextran sulfate sodium (DSS)-induced colitis. The effect of PTGER4+ macrophage secreted molecules was investigated on epithelial organoid differentiation. RESULTS: Here, we describe a subset of PTGER4-expressing intestinal macrophages with mucosal healing properties both in humans and mice. Csf1r-iCre Ptger4fl/fl mice showed defective mucosal healing and epithelial barrier regeneration in a model of DSS colitis. Mechanistically, an increased mucosal level of PGE2 triggers chemokine (C-X-C motif) ligand 1 (CXCL1) secretion in monocyte-derived PTGER4+ macrophages via mitogen-activated protein kinases (MAPKs). CXCL1 drives epithelial cell differentiation and proliferation from regenerating crypts during colitis. Specific therapeutic targeting of macrophages with liposomes loaded with an MAPK agonist augmented the production of CXCL1 in vivo in conditional macrophage PTGER4-deficient mice, restoring their defective epithelial regeneration and favouring mucosal healing. CONCLUSION: PTGER4+ intestinal macrophages are essential for supporting the intestinal stem cell niche and regeneration of the injured epithelium. Our results pave the way for the development of a new class of therapeutic targets to promote macrophage healing functions and favour remission in patients with IBD.


Assuntos
Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Ativação de Macrófagos , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Animais , Diferenciação Celular , Quimiocina CXCL1/metabolismo , Modelos Animais de Doenças , Camundongos , Regeneração , Transdução de Sinais
4.
Biochem Biophys Res Commun ; 521(1): 72-76, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629474

RESUMO

Mast cells express high-affinity IgE receptor (FcεRI) on their surface, cross-linking of which leads to the immediate release of proinflammatory mediators such as histamine but also late-phase cytokine secretion, which are central to the pathogenesis of allergic diseases. Despite the growing evidences that mammalian target of rapamycin (mTOR) plays important roles in the immune system, it is still unclear how mTOR signaling regulates mast cell function. In this study, we investigated the effects of 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-one (3BDO) as an mTOR agonist on FcεRI-mediated allergic responses of mast cells. Our data showed that administration of 3BDO decreased ß-hexosaminidase, interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) release in murine bone marrow-derived mast cells (BMMCs) after FcεRI cross-linking, which was associated with an increase in mTOR complex 1 (mTORC1) signaling but a decrease in activation of Erk1/2, Jnk, and mTORC2-Akt. In addition, we found that a specific Akt agonist, SC79, is able to fully restore the decrease of ß-hexosaminidase release in 3BDO-treated BMMCs but has no effect on IL-6 release in these cells, suggesting that 3BDO negatively regulates FcεRI-mediated degranulation and cytokine release through differential mechanisms in mast cells. The present data demonstrate that proper activation of mTORC1 is crucial for mast cell effector function, suggesting the applicability of the mTORC1 activator as a useful therapeutic agent in mast cell-related diseases.


Assuntos
4-Butirolactona/análogos & derivados , Degranulação Celular/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptores de IgE/antagonistas & inibidores , 4-Butirolactona/farmacologia , Animais , Mastócitos/imunologia , Alvo Mecanístico do Complexo 2 de Rapamicina/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/imunologia , Receptores de IgE/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
5.
Immunity ; 34(4): 505-13, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21497117

RESUMO

Toll-like receptor (TLR) signaling plays a critical role in innate and adaptive immune responses and must be tightly controlled. TLR4 uses LPS binding protein, MD-2, and CD14 as accessories to respond to LPS. We therefore investigated the presence of an analagous soluble cofactor that might assist in the recruitment of CpG oligonucleotides (CpG-ODNs) to TLR9. We report the identification of granulin as an essential secreted cofactor that potentiates TLR9-driven responses to CpG-ODNs. Granulin, an unusual cysteine-rich protein, bound to CpG-ODNs and interacted with TLR9. Macrophages from granulin-deficient mice showed not only impaired delivery of CpG-ODNs to endolysosomal compartments, but also decreased interaction of TLR9 with CpG-ODNs. As a consequence, granulin-deficient macrophages showed reduced responses to stimulation with CpG-ODNs, a trait corrected by provision of exogenous granulin. Thus, we propose that granulin contributes to innate immunity as a critical soluble cofactor for TLR9 signaling.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Transdução de Sinais , Receptor Toll-Like 9/imunologia , Animais , Células Cultivadas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligodesoxirribonucleotídeos/imunologia , Progranulinas , Ligação Proteica , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo
6.
Mol Carcinog ; 58(8): 1492-1501, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31087358

RESUMO

Cellular nucleic acid-binding protein (CNBP) is associated with cell proliferation, and its expression is elevated in human tumors, but the molecular mechanisms of CNBP in tumor cell biology have not been fully elucidated. In this study, we report that CNBP is a transcription factor essential for regulating matrix metalloproteinases mmp-2, mmp-14, and transcription factor e2f2 gene expression by binding to their promoter regions via a sequence-specific manner. Importantly, epidermal growth factor stimulation is required to induce CNBP phosphorylation and nuclear transport, thereby promoting the expression of mmp-2, mmp-14, and e2f2 genes. As a consequence, loss of cnbp attenuates the ability of tumor cell growth, invasion, and migration. Conversely, overexpression of cnbp is associated with tumor cell biology. Collectively, our findings reveal CNBP as a key transcriptional regulator of tumor-promoting target genes to control tumor cell biology.


Assuntos
Fator de Transcrição E2F2/biossíntese , Metaloproteinase 14 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/biossíntese , Neoplasias/patologia , Proteínas de Ligação a RNA/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Linhagem Celular , Proliferação de Células , Fator de Transcrição E2F2/genética , Células HEK293 , Humanos , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 2 da Matriz/genética , Camundongos , Neoplasias/genética , Fosforilação , Regiões Promotoras Genéticas/genética , Ligação Proteica , RNA Mensageiro/biossíntese , Proteínas de Ligação a RNA/genética , Transcrição Gênica/genética , Regulação para Cima/genética
7.
Nucleic Acids Res ; 45(6): 3280-3296, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28168305

RESUMO

The transcription of inflammatory genes is an essential step in host defense activation. Here, we show that cellular nucleic acid-binding protein (CNBP) acts as a transcription regulator that is required for activating the innate immune response. We identified specific CNBP-binding motifs present in the promoter region of sustained inflammatory cytokines, thus, directly inducing the expression of target genes. In particular, lipopolysaccharide (LPS) induced cnbp expression through an NF-κB-dependent manner and a positive autoregulatory mechanism, which enables prolonged il-6 gene expression. This event depends strictly on LPS-induced CNBP nuclear translocation through phosphorylation-mediated dimerization. Consequently, cnbp-depleted zebrafish are highly susceptible to Shigella flexneri infection in vivo. Collectively, these observations identify CNBP as a key transcriptional regulator required for activating and maintaining the immune response.


Assuntos
Interleucina-6/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional , Animais , Sequência de Bases , Núcleo Celular/metabolismo , Células Cultivadas , Sequência Consenso , Citocinas/genética , Disenteria Bacilar/imunologia , Humanos , Subunidade p40 da Interleucina-12/genética , Interleucina-6/biossíntese , Camundongos , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , Domínios Proteicos , Multimerização Proteica , Transporte Proteico , Proteínas de Ligação a RNA/química , Shigella flexneri , Peixe-Zebra
8.
Cell Immunol ; 318: 55-60, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28651742

RESUMO

Toll-like receptor (TLR) signaling drives the innate immune response by activating nuclear factor-κB (NF-κB) and interferon regulatory factor (IRF). We have previously shown that STRAP interacts with TAK1 and IKKα along with NF-κB subunit p65, leading to the activation of pro-inflammatory cytokines. However, the roles of STRAP in TRIF/TBK1-mediated TLR3 activation and the subsequent type I interferon (IFN) production are not fully elucidated. Here, we demonstrate that STRAP acts as a scaffold protein in TLR3-triggered signaling. STRAP strongly interacts with TBK1 and IRF3, which enhances IFN-ß production. As a consequence, STRAP knockdown reduces the level of both pro-inflammatory cytokine and IFN in TLR3 agonist-stimulated macrophages, whereas its overexpression significantly enhances production of these cytokines. Furthermore, the C-terminus of STRAP is essential for its functional activity in TLR3-mediated IL-6 and IFN-ß production. These data suggest that STRAP is a positive regulator of the TLR3-meditated NF-κB and IRF signaling pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Inflamação/imunologia , Macrófagos/imunologia , Receptor 3 Toll-Like/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Citocinas/metabolismo , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/metabolismo , Camundongos , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Células RAW 264.7 , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA , Transdução de Sinais
9.
J Immunol ; 193(7): 3726-35, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25187653

RESUMO

TLR signaling is essential to innate immunity against microbial invaders and must be tightly controlled. We have previously shown that TLR9 undergoes proteolytic cleavage processing by lysosomal proteases to generate two distinct fragments. The C-terminal cleavage product plays a critical role in activating TLR9 signaling; however, the precise role of the N-terminal fragment, which remains in lysosomes, in the TLR9 response is still unclear. In this article, we report that the N-terminal cleavage product negatively regulates TLR9 signaling. Notably, the N-terminal fragment promotes the aspartic protease-mediated degradation of the C-terminal fragment in endolysosomes. Furthermore, the N-terminal TLR9 fragment physically interacts with the C-terminal product, thereby inhibiting the formation of homodimers of the C-terminal fragment; this suggests that the monomeric C-terminal product is more susceptible to attack by aspartic proteases. Together, these results suggest that the N-terminal TLR9 proteolytic cleavage product is a negative self-regulator that prevents excessive TLR9 signaling activity.


Assuntos
Endossomos/imunologia , Lisossomos/imunologia , Proteólise , Transdução de Sinais/imunologia , Receptor Toll-Like 9/imunologia , Animais , Ácido Aspártico Proteases/genética , Ácido Aspártico Proteases/imunologia , Endossomos/genética , Células HEK293 , Humanos , Lisossomos/genética , Camundongos , Multimerização Proteica/genética , Multimerização Proteica/imunologia , Estrutura Terciária de Proteína , Transdução de Sinais/genética , Receptor Toll-Like 9/genética
10.
Hepatogastroenterology ; 62(138): 383-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25916068

RESUMO

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) recurrence is observed in up to 70-80% of patients despite a curative treatment. Microvascular invasion (MVI) and poor differentiation are strong risk factors for recurrence, but these cannot be known preoperatively. The aim of this study was to investigate the correlation of 18F-FDG PET with MVI and differentiation, and predictive role of tumor-to-background ratio of PET for recurrence in HCC. METHODOLOGY: Fifty-four patients had 18F-FDG PET/CT study before surgical resection as a first treatment of HCC between December 2008 and December 2012. We analyzed the predictive role of metabolic parameters of PET for recurrence of HCC. Maximal standardized uptake value, tumor-to-nontumor ratio, tumor-to-muscle ratio (TMR) and tumor-to-blood ratio were tested as metabolic index of 18F-FDG PET. RESULTS: Twenty-seven patients had increased uptake in preoperative PET and 14 (51.9%) of them experienced the recurrence. Increased uptake in PET and TMR were associated with MVI (p = 0.04, p = 0.005) and histologic differentiation (p = 0.018, p = 0.002). MVI was the only predictive factor for re- currence in multivariate analysis although TMR ≥ 6.36 showed a favorable result despite no statistical significance (p = 0.061). CONCLUSIONS: Increased 18F-FDG uptake of HCC, especially high TMR might be correlated with MVI and poor differentiation, and tends to have a risk for recurrence in HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias Hepáticas/diagnóstico por imagem , Músculo Liso Vascular/diagnóstico por imagem , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Diferenciação Celular , Distribuição de Qui-Quadrado , Feminino , Hepatectomia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Microvasos/diagnóstico por imagem , Microvasos/patologia , Pessoa de Meia-Idade , Imagem Multimodal , Análise Multivariada , Músculo Liso Vascular/patologia , Invasividade Neoplásica , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Proc Natl Acad Sci U S A ; 108(1): 337-42, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21173222

RESUMO

EBV nuclear antigen 3C (EBNA3C) is an essential transcription factor for EBV transformed lymphoblast cell line (LCL) growth. To identify EBNA3C-regulated genes in LCLs, microarrays were used to measure RNA abundances in each of three different LCLs that conditionally express EBNA3C fused to a 4-OH-Tamoxifen-dependent estrogen receptor hormone binding domain (EBNA3CHT). At least three RNAs were assayed for each EBNA3CHT LCL under nonpermissive conditions, permissive conditions, and nonpermissive conditions with wild-type EBNA3C transcomplementation. Using a two-way ANOVA model of EBNA3C levels, we identified 550 regulated genes that were at least 1.5-fold up- or down-regulated with false discovery rates < 0.01. EBNA3C-regulated genes overlapped significantly with genes regulated by EBNA2 and EBNA3A consistent with coordinated effects on cell gene transcription. Of the 550 EBNA3C-regulated genes, 106 could be placed in protein networks. A seeded Bayesian network analysis of the 80 most significant EBNA3C-regulated genes suggests that RAC1, LYN, and TNF are upstream of other EBNA3C-regulated genes. Gene set enrichment analysis found enrichment for MAP kinase signaling, cytokine-cytokine receptor interactions, JAK-STAT signaling, and cell adhesion molecules, implicating these pathways in EBNA3C effects on LCL growth or survival. EBNA3C significantly up-regulated the CXCL12 ligand and its CXCR4 receptor and increased LCL migration. CXCL12 up-regulation depended on EBNA3C's interaction with the cell transcription factor, RBPJ, which is essential for LCL growth. EBNA3C also up-regulated MYC 1.3-fold and down-regulated CDKN2A exons 2 and 3, shared by p16 and p14, 1.4-fold, with false discovery rates < 5 × 10(-4).


Assuntos
Antígenos Virais/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Genes/genética , Fatores de Transcrição/metabolismo , Análise de Variância , Teorema de Bayes , Linhagem Celular Tumoral , Análise por Conglomerados , Antígenos Nucleares do Vírus Epstein-Barr , Perfilação da Expressão Gênica , Humanos , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Ativação Linfocitária , Análise em Microsséries , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Clin Mol Hepatol ; 30(2): 247-262, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281815

RESUMO

BACKGROUND/AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by fat accumulation in the liver. MASLD encompasses both steatosis and MASH. Since MASH can lead to cirrhosis and liver cancer, steatosis and MASH must be distinguished during patient treatment. Here, we investigate the genomes, epigenomes, and transcriptomes of MASLD patients to identify signature gene set for more accurate tracking of MASLD progression. METHODS: Biopsy-tissue and blood samples from patients with 134 MASLD, comprising 60 steatosis and 74 MASH patients were performed omics analysis. SVM learning algorithm were used to calculate most predictive features. Linear regression was applied to find signature gene set that distinguish the stage of MASLD and to validate their application into independent cohort of MASLD. RESULTS: After performing WGS, WES, WGBS, and total RNA-seq on 134 biopsy samples from confirmed MASLD patients, we provided 1,955 MASLD-associated features, out of 3,176 somatic variant callings, 58 DMRs, and 1,393 DEGs that track MASLD progression. Then, we used a SVM learning algorithm to analyze the data and select the most predictive features. Using linear regression, we identified a signature gene set capable of differentiating the various stages of MASLD and verified it in different independent cohorts of MASLD and a liver cancer cohort. CONCLUSION: We identified a signature gene set (i.e., CAPG, HYAL3, WIPI1, TREM2, SPP1, and RNASE6) with strong potential as a panel of diagnostic genes of MASLD-associated disease.


Assuntos
Fígado Gorduroso , Neoplasias Hepáticas , Humanos , Algoritmos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Progressão da Doença
13.
Nat Commun ; 14(1): 700, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36755029

RESUMO

The cortical actin cytoskeleton plays a critical role in maintaining intestinal epithelial integrity, and the loss of this architecture leads to chronic inflammation, as seen in inflammatory bowel disease (IBD). However, the exact mechanisms underlying aberrant actin remodeling in pathological states remain largely unknown. Here, we show that a subset of patients with IBD exhibits substantially higher levels of tripartite motif-containing protein 40 (TRIM40), a gene that is hardly detectable in healthy individuals. TRIM40 is an E3 ligase that directly targets Rho-associated coiled-coil-containing protein kinase 1 (ROCK1), an essential kinase involved in promoting cell-cell junctions, markedly decreasing the phosphorylation of key signaling factors critical for cortical actin formation and stabilization. This causes failure of the epithelial barrier function, thereby promoting a long-lived inflammatory response. A mutant TRIM40 lacking the RING, B-box, or C-terminal domains has impaired ability to accelerate ROCK1 degradation-driven cortical actin disruption. Accordingly, Trim40-deficient male mice are highly resistant to dextran sulfate sodium (DSS)-induced colitis. Our findings highlight that aberrant upregulation of TRIM40, which is epigenetically silenced under healthy conditions, drives IBD by subverting cortical actin formation and exacerbating epithelial barrier dysfunction.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Proteínas com Motivo Tripartido , Animais , Masculino , Camundongos , Actinas/metabolismo , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Intestinos , Camundongos Endogâmicos C57BL , Humanos , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo
14.
Nat Commun ; 13(1): 5203, 2022 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-36057640

RESUMO

Inflammatory cytokines are key signaling molecules that can promote an immune response, thus their RNA turnover must be tightly controlled during infection. Most studies investigate the RNA decay pathways in the cytosol or nucleoplasm but never focused on the nucleolus. Although this organelle has well-studied roles in ribosome biogenesis and cellular stress sensing, the mechanism of RNA decay within the nucleolus is not completely understood. Here, we report that the nucleolus is an essential site of inflammatory pre-mRNA instability during infection. RNA-sequencing analysis reveals that not only do inflammatory genes have higher intronic read densities compared with non-inflammatory genes, but their pre-mRNAs are highly enriched in nucleoli during infection. Notably, nucleolin (NCL) acts as a guide factor for recruiting cytosine or uracil (C/U)-rich sequence-containing inflammatory pre-mRNAs and the Rrp6-exosome complex to the nucleolus through a physical interaction, thereby enabling targeted RNA delivery to Rrp6-exosomes and subsequent degradation. Consequently, Ncl depletion causes aberrant hyperinflammation, resulting in a severe lethality in response to LPS. Importantly, the dynamics of NCL post-translational modifications determine its functional activity in phases of LPS. This process represents a nucleolus-dependent pathway for maintaining inflammatory gene expression integrity and immunological homeostasis during infection.


Assuntos
Nucléolo Celular , Lipopolissacarídeos , Nucléolo Celular/metabolismo , Núcleo Celular , Lipopolissacarídeos/metabolismo , RNA/metabolismo , Estabilidade de RNA
15.
Ophthalmol Sci ; 1(4): 100065, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36246939

RESUMO

Purpose: To determine the safety, efficacy, and tolerability of combinations of pilocarpine (Pilo) and oxymetazoline (Oxy) ocular drops dosed once daily and identify the optimal concentration of each for the pharmacologic treatment of presbyopia. Design: Two concurrent Phase 2, multicenter, double-masked, randomized, vehicle-controlled studies, 1 short-term and 1 extended study. Participants: Emmetropic individuals affected by presbyopia and in good general health. Methods: Uncorrected near visual acuity (UNVA) was measured throughout both studies with various concentrations and combinations of Pilo (0%, 0.5% 1.0%, and 1.5%) and Oxy (0%, 0.0125%, 0.05%, and 0.125%). For safety, uncorrected distance visual acuity (UDVA) was measured, treatment-emergent adverse events (TEAEs) were recorded, and a temporal/supraorbital headache assessment was completed. Main Outcome Measures: The primary efficacy end point was mean change from baseline in UNVA. Results: In the short-term study, Pilo was shown to produce a significant dose response in the average increase of letters (P < 0.001), whereas Oxy did not have a significant impact (P = 0.4797). The addition or increase in concentration of Oxy did not reduce incidence or severity of headaches when compared with Pilo alone. Efficacy results from the extended study supported the results from the short-term study. As early as 15 minutes postadministration, a dose response could be seen, with peak effect at 1 hour. Peak improvement increased from day 1 to day 14 and was maintained up to day 28. The most common TEAE was headache. There was no clinically significant reduction in UDVA. A polynomial regression model was developed and determined that the optimal concentration range of Pilo is between 1.16% and 1.32%. Conclusions: On the basis of the results of the 2 Phase 2 studies, AGN-190584, a reading drop containing an optimized concentration of pilocarpine HCl (1.25%) delivered using a proprietary formulation, was developed and is currently under investigation in Phase 3 studies.

16.
J Virol ; 83(23): 12368-77, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19776126

RESUMO

B lymphocytes converted into lymphoblastoid cell lines (LCLs) by an Epstein-Barr virus that expresses a conditional EBNA3C require complementation with EBNA3C for growth under nonpermissive conditions. Complementation with relatively large EBNA3C deletion mutants identified amino acids (aa) 1 to 506 (which includes the RBP-Jkappa/CSL [RBP-Jkappa] binding domain) and 733 to 909 to be essential for LCL growth, aa 728 to 732 and 910 to 992 to be important for full wild-type (wt) growth, and only aa 507 to 727 to be unimportant (S. Maruo, Y. Wu, T. Ito, T. Kanda, E. D. Kieff, and K. Takada, Proc. Natl. Acad. Sci. USA 106:4419-4424, 2009). When mutants with smaller deletions were used, only aa 51 to 400 and 851 to 900 were essential for LCL growth; aa 447 to 544, 701 to 750, 801 to 850, and 901 to 992 were important for full wt growth; and aa 4 to 50, 401 to 450, 550 to 707, and 751 to 800 were unimportant. These data reduce the EBNA3C essential residues from 68% to 40% of the open reading frame. Point mutations confirmed RBP-Jkappa binding to be essential for wt growth and indicated that SUMO and CtBP binding interactions were important only for full wt growth. EBNA3C aa 51 to 150, 249 to 311, and 851 to 900 were necessary for maintaining LCL growth, but not RBP-Jkappa interaction, and likely mediate interactions with other key cell proteins. Moreover, all mutants null for LCL growth had fewer S+G(2)/M-phase cells at 14 days, consistent with EBNA3C interaction with RBP-Jkappa as well as aa 51 to 150, 249 to 311, and 851 to 900 being required to suppress p16(INK4A) (S. Maruo, Y. Wu, S. Ishikawa, T. Kanda, D. Iwakiri, and K. Takada, Proc. Natl. Acad. Sci. USA 103:19500-19505, 2006). We have confirmed that EBNA3C upregulates TCL1 and discovered that EBNA3C upregulates TCL1 through RBP-Jkappa, indicating a central role for EBNA3C interaction with RBP-Jkappa in mediating cell gene transcription.


Assuntos
Antígenos Virais/fisiologia , Transformação Celular Neoplásica , Herpesvirus Humano 4/patogenicidade , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Proteínas Proto-Oncogênicas/biossíntese , Antígenos Virais/genética , Linhagem Celular Tumoral , Antígenos Nucleares do Vírus Epstein-Barr , Herpesvirus Humano 4/genética , Humanos , Mutagênese Sítio-Dirigida , Mutação Puntual , Domínios e Motivos de Interação entre Proteínas , Deleção de Sequência , Regulação para Cima
17.
Ultrasonography ; 39(1): 94-101, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31786906

RESUMO

The conventional radiologic method for liver segmentation is based on the position of the hepatic and portal veins. However, during surgery, liver segments are resected based on the distribution of hepatic portal blood flow. This discrepancy can lead to a number of problems, such as miscommunication among clinicians, missing the location of the segment with the hepatic mass, and the risk of extended hepatic resection. We suggest a novel method to determine hepatic segments based on portal blood flow, as in the surgical approach, but by using high and low mechanical indexes in contrast-enhanced ultrasonography with Sonazoid. This approach is helpful for preoperatively determining hepatic segments and reducing the risk of missing the location of a hepatic tumor or extended hepatic resection.

18.
Hepatogastroenterology ; 56(91-92): 763-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19621698

RESUMO

BACKGROUND/AIMS: Alpha-fetoprotein (AFP) and protein-induced by vitamin K absence or antagonist (PIVKA-II) are representative markers of hepatocellular carcinoma (HCC). The aim of this study was to evaluate the usefulness of PIVKA-II when compared with AFP for detecting HCC. Furthermore, we evaluated the correlation between PIVKA-II and HCC staging. METHODOLOGY: One hundred patients with liver cirrhosis (LC) and 227 with HCC were analyzed between January 2004 and March 2006. To compare the diagnostic value of PIVKA-II and AFP, Receiver operating characteristic curve was constructed. RESULTS: The area under the curve indicated a better accuracy for PIVKA-II than AFP in diagnosis of HCC (0.829 vs. 0.712). The positive rates of PIVKA-II in patients with tumor size larger than 5 cm, 3-5 cm, and less than 3 cm were higher than that of AFP (96%, 83%, 74% vs. 65%, 57%, 48%, respectively). In addition, there seems to be correlation between PIVKA-II and staging systems, Tumor Node Metastasis, Cancer of the Liver Italian Program score and Japan Integrated Staging score (p<0.05). CONCLUSIONS: The results of this study show that a PIVKA-II is a useful marker for detecting HCC, especially in small HCC and may have correlations with known staging systems.


Assuntos
Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/patologia , Precursores de Proteínas/sangue , alfa-Fetoproteínas/metabolismo , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Protrombina , Reprodutibilidade dos Testes , Estudos Retrospectivos
19.
Nat Commun ; 10(1): 4670, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604943

RESUMO

The mechanisms by which many human cytomegalovirus (HCMV)-encoded proteins help the virus to evade immune surveillance remain poorly understood. In particular, it is unknown whether HCMV proteins arrest Toll-like receptor (TLR) signaling pathways required for antiviral defense. Here, we report that US7 and US8 as key suppressors that bind both TLR3 and TLR4, facilitating their destabilization by distinct mechanisms. US7 exploits the ER-associated degradation components Derlin-1 and Sec61, promoting ubiquitination of TLR3 and TLR4. US8 not only disrupts the TLR3-UNC93B1 association but also targets TLR4 to the lysosome, resulting in rapid degradation of the TLR. Accordingly, a mutant HCMV lacking the US7-US16 region has an impaired ability to hinder TLR3 and TLR4 activation, and the impairment is reversed by the introduction of US7 or US8. Our findings reveal an inhibitory effect of HCMV on TLR signaling, which contributes to persistent avoidance of the host antiviral response to achieve viral latency.


Assuntos
Citomegalovirus/patogenicidade , Imunidade Inata , Glicoproteínas de Membrana/fisiologia , Receptores Toll-Like/metabolismo , Proteínas Virais/fisiologia , Linhagem Celular , Humanos , Glicoproteínas de Membrana/química , Complexo de Endopeptidases do Proteassoma/fisiologia , Domínios Proteicos , Proteólise , Transdução de Sinais , Receptores Toll-Like/genética , Receptores Toll-Like/fisiologia , Ubiquitina/metabolismo , Proteínas Virais/química
20.
Exp Mol Med ; 40(4): 427-34, 2008 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-18779655

RESUMO

Use of adenoviruses as vehicle for gene therapy requires that target cells express appropriate receptors such as coxsakievirus and adenovirus receptor (CAR). We show here that CAR-deficiency in cancer cells, that limits adenoviral gene delivery, can be overcome by using adenovirus complexed with the liposome, Ad-PEGPE [1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(poly-ethylene glycol)-2000]. We first confirmed that CT-26 mouse colon cancer cells are deficient in CAR by RT-PCR, and then showed that CT-26 cells infected with Ad-GFP/PEGPE exhibited highly enhanced expression of green fluorescent protein (GFP), compared with those infected with Ad-GFP. GFP expression depends on the dose of liposome and adenovirus. Luciferase expression in livers treated with Ad-luc/PEGPE was about 1,000-fold less than those infected with Ad-luc. In a liver metastasis mouse tumor model developed by intrasplenic injection of CT-26 cells, luciferase expression following i.v. injection of Ad-luc/PEGPE was significantly higher in tumors than in adjacent non-neoplastic liver. Following systemic administration of Ad-GFP/PEGPE, GFP expression increased in tumors more than in adjacent liver while the reverse was true following administration of Ad-GFP. In the latter case, GFP expression was higher in liver than in tumors. This study demonstrates that systemic delivery of PEGPE-adenovirus complex is an effective tool of adenoviral delivery as it overcomes limitation due to CAR deficiency of target cells while reducing hepatic uptake and enhancing adenoviral gene expression in tumors.


Assuntos
Adenoviridae , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Técnicas de Transferência de Genes , Lipossomos/uso terapêutico , Receptores Virais/genética , Adenoviridae/genética , Adenoviridae/metabolismo , Animais , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Receptor Constitutivo de Androstano , Relação Dose-Resposta a Droga , Terapia Genética , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/farmacocinética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Células NIH 3T3 , Fosfatidiletanolaminas/administração & dosagem , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/farmacocinética , Fosfatidiletanolaminas/uso terapêutico , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/uso terapêutico , Receptores Citoplasmáticos e Nucleares/deficiência , Receptores Citoplasmáticos e Nucleares/genética , Receptores Virais/deficiência , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Células Tumorais Cultivadas
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