Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Transl Med ; 22(1): 316, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549133

RESUMO

BACKGROUND: Propofol is a widely used anesthetic and sedative, which has been reported to exert an anti-inflammatory effect. TLR4 plays a critical role in coordinating the immuno-inflammatory response during sepsis. Whether propofol can act as an immunomodulator through regulating TLR4 is still unclear. Given its potential as a sepsis therapy, we investigated the mechanisms underlying the immunomodulatory activity of propofol. METHODS: The effects of propofol on TLR4 and Rab5a (a master regulator involved in intracellular trafficking of immune factors) were investigated in macrophage (from Rab5a-/- and WT mice) following treatment with lipopolysaccharide (LPS) or cecal ligation and puncture (CLP) in vitro and in vivo, and peripheral blood monocyte from sepsis patients and healthy volunteers. RESULTS: We showed that propofol reduced membrane TLR4 expression on macrophages in vitro and in vivo. Rab5a participated in TLR4 intracellular trafficking and both Rab5a expression and the interaction between Rab5a and TLR4 were inhibited by propofol. We also showed Rab5a upregulation in peripheral blood monocytes of septic patients, accompanied by increased TLR4 expression on the cell surface. Propofol downregulated the expression of Rab5a and TLR4 in these cells. CONCLUSIONS: We demonstrated that Rab5a regulates intracellular trafficking of TLR4 and that propofol reduces membrane TLR4 expression on macrophages by targeting Rab5a. Our study not only reveals a novel mechanism for the immunomodulatory effect of propofol but also indicates that Rab5a may be a potential therapeutic target against sepsis.


Assuntos
Propofol , Sepse , Camundongos , Humanos , Animais , Propofol/farmacologia , Propofol/uso terapêutico , Propofol/metabolismo , Receptor 4 Toll-Like/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Sepse/complicações , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo
2.
Eur Respir J ; 61(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36229053

RESUMO

INTRODUCTION: Acute lung injury (ALI) is a major cause of morbidity and mortality after intestinal ischaemia/reperfusion (I/R). The gut microbiota and its metabolic byproducts act as important modulators of the gut-lung axis. This study aimed to define the role of succinate, a key microbiota metabolite, in intestinal I/R-induced ALI progression. METHODS: Gut and lung microbiota of mice subjected to intestinal I/R were analysed using 16S rRNA gene sequencing. Succinate level alterations were measured in germ-free mice or conventional mice treated with antibiotics. Succinate-induced alveolar macrophage polarisation and its effects on alveolar epithelial apoptosis were evaluated in succinate receptor 1 (Sucnr1)-deficient mice and in murine alveolar macrophages transfected with Sucnr1-short interfering RNA. Succinate levels were measured in patients undergoing cardiopulmonary bypass, including intestinal I/R. RESULTS: Succinate accumulated in lungs after intestinal I/R, and this was associated with an imbalance of succinate-producing and succinate-consuming bacteria in the gut, but not the lungs. Succinate accumulation was absent in germ-free mice and was reversed by gut microbiota depletion with antibiotics, indicating that the gut microbiota is a source of lung succinate. Moreover, succinate promoted alveolar macrophage polarisation, alveolar epithelial apoptosis and lung injury during intestinal I/R. Conversely, knockdown of Sucnr1 or blockage of SUCNR1 in vitro and in vivo reversed the effects of succinate by modulating the phosphoinositide 3-kinase-AKT/hypoxia-inducible factor-1α pathway. Plasma succinate levels significantly correlated with intestinal I/R-related lung injury after cardiopulmonary bypass. CONCLUSION: Gut microbiota-derived succinate exacerbates intestinal I/R-induced ALI through SUCNR1-dependent alveolar macrophage polarisation, identifying succinate as a novel target for gut-derived ALI in critically ill patients.


Assuntos
Lesão Pulmonar Aguda , Microbioma Gastrointestinal , Traumatismo por Reperfusão , Camundongos , Animais , Ácido Succínico/metabolismo , Fosfatidilinositol 3-Quinases , RNA Ribossômico 16S/genética , Lesão Pulmonar Aguda/complicações , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , Reperfusão , Isquemia/complicações , Camundongos Endogâmicos C57BL
3.
Molecules ; 28(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37446848

RESUMO

A rapid and convenient homogeneous aptamer sensor with high sensitivity is highly desirable for the electrochemical detection of tumor biomarkers. In this work, a homogeneous electrochemical aptamer sensor is demonstrated based on a two-dimensional (2D) nanocomposite probe and nanochannel modified electrode, which can realize sensitive detection of carcinoembryonic antigen (CEA). Using π-π stacking and electrostatic interaction, CEA aptamer (Apt) and cationic redox probe (hexaammineruthenium(III), Ru(NH3)63+) are co-loaded on graphite oxide (GO), leading to a 2D nanocomposite probe (Ru(NH3)63+/Apt@GO). Vertically ordered mesoporous silica-nanochannel film (VMSF) is easily grown on the supporting indium tin oxide (ITO) electrode (VMSF/ITO) using the electrochemical assisted self-assembly (EASA) method within 10 s. The ultrasmall nanochannels of VMSF exhibits electrostatic enrichment towards Ru(NH3)63+ and size exclusion towards 2D material. When CEA is added in the Ru(NH3)63+/Apt@GO solution, DNA aptamer recognizes and binds to CEA and Ru(NH3)63+ releases to the solution, which can be enriched and detected by VMSF/ITO electrodes. Based on this mechanism, CEA can be an electrochemical detection ranging from 60 fg/mL to 100 ng/mL with a limit of detection (LOD) of 14 fg/mL. Detection of CEA in human serum is also realized. The constructed homogeneous detection system does not require the fixation of a recognitive aptamer on the electrode surface or magnetic separation before detection, demonstrating potential applications in rapid, convenient and sensitive electrochemical sensing of tumor biomarkers.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Humanos , Antígeno Carcinoembrionário , Técnicas Biossensoriais/métodos , Biomarcadores Tumorais , Eletrodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
4.
Funct Integr Genomics ; 22(5): 977-988, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35725976

RESUMO

Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are essential regulators in human cancers, while the role of lncRNA X-inactive-specific transcript (XIST) in colorectal cancer (CRC) via regulating miR-448 remains largely unknown. Herein, we aimed to elucidate the effect of the XIST/miR-448/grainyhead-like 2 (GRHL2) axis on CRC development. XIST, miR-448, and GRHL2 expression in CRC tissues from patients and in human CRC cell lines was assessed. Loss- and gain-function assays were implemented to unveil the roles of XIST, miR-448, and GRHL2 in screened CRC cells. The tumor growth in vivo was observed in nude mice. Binding relations among XIST, miR-448, and GRHL2 were evaluated. XIST and GRHL2 expressed highly whereas miR-448 expressed lowly in CRC tissues and cells. XIST or GRHL2 downregulation, or miR-448 elevation suppressed the malignant behaviors of CRC cells in vitro, and downregulated XIST or upregulated miR-448 also inhibited the tumor growth in vivo. miR-448 upregulation reversed the role of XIST elevation in CRC cells. XIST particularly bound to miR-448, and miR-448 targeted GRHL2. Knockdown of XIST upregulates miR-448 to impede malignant behaviors of CRC cells via inhibiting GRHL2. This study may provide novel biomarkers for CRC diagnosis and treatment.


Assuntos
Neoplasias Colorretais , MicroRNAs , RNA Longo não Codificante , Animais , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Dig Dis Sci ; 67(5): 1794-1805, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33839982

RESUMO

BACKGROUND: Emerging evidence has suggested that miRNAs are important regulators of intestinal I/R injury, but their function in this context remains elusive. AIMS: To evaluate the role of miR-26b-5p in intestinal I/R injury. METHODS: We utilized in vivo murine models of intestinal I/R and in vitro Mode-K cell-based models of oxygen and glucose deprivation/reperfusion (OGD/R) to examine the function of miR-26b-5p in intestinal I/R injury. The expression of miR-26b-5p in intestinal mucosa and Mode-K cell was detected by RT-PCR. HE staining and Chiu's score were used to evaluate intestinal mucosa injury severity. Apoptosis was detected by TUNEL stain, flow cytometry, and western blot. TargetScan and StarBase prediction algorithms were applied to predict putative target genes of miR-26b-5p and validated by luciferase reporter analyses. RESULTS: We found that the expression of miR-26b-5p in intestinal mucosa was markedly decreased during I/R injury. We additionally found miR-26b-5p overexpression to markedly disrupt intestinal I/R- or OGD/R-induced injury in vivo and in vitro, whereas inhibiting this miRNA had an adverse impact and resulted in increased intestinal tissue injury and Mode-K cell damage. From a mechanistic perspective, miR-26b-5p was predicted to target DAPK1, which was related to cellular apoptosis. Luciferase reporter assay results confirmed that miR-26b-5p directly targets DAPK1 in Mode-K cells, thereby suppressing OGD/R-induced cell apoptosis. CONCLUSION: Our findings show that miR-26b-5p may prevent intestinal I/R injury via targeting DAPK1 and inhibiting intestinal mucosal cell apoptosis, suggesting that this miRNA may be a viable target for the treatment of intestinal I/R injury.


Assuntos
MicroRNAs , Traumatismo por Reperfusão , Animais , Apoptose/genética , Proteínas Quinases Associadas com Morte Celular/genética , Glucose , Humanos , Mucosa Intestinal/metabolismo , Isquemia , Camundongos , MicroRNAs/metabolismo , Oxigênio , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle
6.
Platelets ; 33(4): 612-620, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34448680

RESUMO

Thrombocytopenia is common in critical illness. But there are no studies that focus on thrombocytopenia and platelet recovery in Sepsis-3 patients. We employed a large database to identify sepsis based on Sepsis-3 criteria. Patients were grouped by nadir platelet count during ICU, propensity score matching was used to eliminate covariates imbalance, multivariable cox proportional hazard model was used for evaluating mortality. A total of 9709 patients were enrolled based on Sepsis-3, 1794 (18%) patients developed thrombocytopenia, with 858 (8.8%) exhibiting thrombocytopenia at ICU admission (prevalent), 891 (9.2%) developed thrombocytopenia during ICU stay (incident). In the incident thrombocytopenia group, survivors exhibited higher nadir platelet count, higher rate in platelet count recovery and shorter time to platelet recovery compared to non-survivors. Platelet recovery was not observed until 1 days (IQR, 1-2) after weaning of mechanical ventilation and 1 days (IQR, 1-3) after discontinuation of vasopressor in survivors of incident thrombocytopenia. Furthermore, thrombocytopenia was associated with longer duration of ICU length of stay, longer duration of mechanical ventilation and vasopressor use compared to no thrombocytopenia. Moderate (20-50 × 109/L) and severe (<20 × 109/L) thrombocytopenia group showed increased 28 days mortality compared to no thrombocytopenia, while the mortality rate between mild (51-100 × 109/L) and no thrombocytopenia group (≥100 × 109/L) showed no significant difference. Taken together these data revealed that thrombocytopenia occurred in 18% Sepsis-3 patients; platelet recovery occurred more frequent and earlier in survivors; platelet recovery was not observed until clinical improvement. Thrombocytopenia in Sepsis-3 demonstrated increased disease severity, and patients with platelet count <50 × 109/L showed increased 28 days mortality.


Assuntos
Sepse , Trombocitopenia , Humanos , Contagem de Plaquetas , Prognóstico , Estudos Retrospectivos , Sepse/complicações , Trombocitopenia/complicações
7.
Molecules ; 27(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36296370

RESUMO

Convenient and sensitive detection of tumor biomarkers is crucial for the early diagnosis and treatment of cancer. Herein, we present a probe-integrated and label-free electrochemical immunosensor based on binary nanocarbon composites and surface-immobilized methylene blue (MB) redox probes for detection of carbohydrate antigen 199 (CA19-9), which is closely associated with gastric malignancies. Nanocarbon composites consisting of electrochemically reduced graphene oxides and carbon nanotubes (ErGO-CNT) are electrodeposited onto an indium tin oxide (ITO) electrode surface to form a 3D nanocomposite film, which could provide high surface area to immobilize abundant MB probes, facilitate the electron transfer of MB, and therefore, improve sensitivity. Polydopamine (PDA) served as a bifunctional linker is able to immobilize anti-CA19-9 antibodies and stabilize the inner probe, conferring the sensing interface with specific recognition capacity. Electrochemical detection of CA19-9 is achieved based on the decrease of the redox signal of MB after specific binding of CA19-9 with a wide linear range of 0.1 mU/mL to 100 U/mL and a limit of detection (LOD) of 0.54 nU/mL (S/N = 3). The constructed electrochemical immunosensor has good selectivity, repeatability, reproducibility, and stability. Furthermore, determination of CA19-9 in human serum samples is also realized.


Assuntos
Técnicas Biossensoriais , Grafite , Nanotubos de Carbono , Humanos , Técnicas Eletroquímicas , Azul de Metileno , Imunoensaio , Reprodutibilidade dos Testes , Limite de Detecção , Óxidos , Biomarcadores Tumorais , Carboidratos , Ouro
8.
Eur Radiol ; 31(12): 8967-8974, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34032918

RESUMO

OBJECTIVES: We attempted to improve the accuracy of coronary CT angiography (CCTA)-derived fractional flow reserve (FFR) (FFRCT) by expanding the coronary tree in the computational fluid dynamics (CFD) domain. An observational study was performed to evaluate the effects of extending the coronary tree analysis for FFRCT from a minimal diameter of 1.2 to 0.8 mm. METHODS: Patients who underwent CCTA and interventional FFR were enrolled retrospectively. Seventy-six patients qualified based on the inclusion criteria. The three-dimensional (3D) coronary artery tree was reconstructed to generate a finite element mesh for each subject with different lower limits of luminal diameter (1.2 mm and 0.8 mm). Outlet boundary conditions were defined according to Murray's law. The Newton-Krylov-Schwarz (NKS) method was applied to solve the governing equations of CFD to derive FFRCT. RESULTS: At the individual patient level, extending the minimal diameter of the coronary tree from 1.2 to 0.8 mm improved the sensitivity of FFRCT by 16.7% (p = 0.022). This led to the conversion of four false-negative cases into true-positive cases. The AUC value of the ROC curve increased from 0.74 to 0.83. Moreover, the NKS method can solve the computational problem of extending the coronary tree to an 0.8-mm luminal diameter in 10.5 min with 2160 processor cores. CONCLUSIONS: Extending the reconstructed coronary tree to a smaller luminal diameter can considerably improve the sensitivity of FFRCT. The NKS method can achieve favorable computational times for future clinical applications. KEY POINTS: • Extending the reconstructed coronary tree to a smaller luminal diameter can considerably improve the sensitivity of FFRCT. • The NKS method applied in our study can effectively reduce the computational time of this process for future clinical applications.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
9.
Hepatology ; 69(4): 1751-1767, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30506577

RESUMO

Sepsis-induced liver injury is recognized as a key problem in intensive care units. The gut microbiota has been touted as an important mediator of liver disease development; however, the precise roles of gut microbiota in regulating sepsis-induced liver injury are unknown. Here, we aimed to investigate the role of the gut microbiota in sepsis-induced liver injury and the underlying mechanism. Cecal ligation and puncture (CLP) was used to induce polymicrobial sepsis and related liver injury. Fecal microbiota transplantation (FMT) was used to validate the roles of gut microbiota in these pathologies. Metabolomics analysis was performed to characterize the metabolic profile differences between sepsis-resistant (Res; survived to 7 days after CLP) and sepsis-sensitive (Sen; moribund before or approximately 24 hours after CLP) mice. Mice gavaged with feces from Sen mice displayed more-severe liver damage than did mice gavaged with feces from Res mice. The gut microbial metabolic profile between Sen and Res mice was different. In particular, the microbiota from Res mice generated more granisetron, a 5-hydroxytryptamine 3 (5-HT3 ) receptor antagonist, than the microbiota from Sen mice. Granisetron protected mice against CLP-induced death and liver injury. Moreover, proinflammatory cytokine expression by macrophages after lipopolysaccharide (LPS) challenge was markedly reduced in the presence of granisetron. Both treatment with granisetron and genetic knockdown of the 5-HT3A receptor in cells suppressed nuclear factor kappa B (NF-кB) transactivation and phosphorylated p38 (p-p38) accumulation in macrophages. Gut microbial granisetron levels showed a significantly negative correlation with plasma alanine aminotransferase (ALT)/aspartate aminotransferase (AST) levels in septic patients. Conclusion: Our study indicated that gut microbiota plays a key role in the sensitization of sepsis-induced liver injury and associates granisetron as a hepatoprotective compound during sepsis development.


Assuntos
Coinfecção/complicações , Microbioma Gastrointestinal , Granisetron/metabolismo , Hepatopatias/microbiologia , Sepse/microbiologia , Animais , Citocromo P-450 CYP1A1/metabolismo , Citocinas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Células RAW 264.7 , Receptores 5-HT3 de Serotonina/genética , Receptores 5-HT3 de Serotonina/metabolismo , Receptor 4 Toll-Like/metabolismo
10.
Cytokine ; 125: 154854, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539844

RESUMO

BACKGROUND: Sepsis is a major cause of death for ICU patients. Sepsis development depends heavily on the presence of mature IL-1ß cytokine. This study evaluates the potential therapeutic properties of a bioactive compound known as 6-gingerol on sepsis. This compound has previously been demonstrated to possess anti-inflammatory properties both in vivo and in vitro. METHODS: C57BL/6 mice was used to establish models of sepsis by means of cecal ligation and puncture (CLP). Upon treatment with 6-gingerol, we assessed the survival rate of mice and measured the levels of key pro-inflammatory cytokines in serum and colon tissues. Sepsis pathogenesis was further explored using the RAW264.7 cell line and bone marrow-derived macrophages (BMDMs) treated with ATP and lipopolysaccharide (LPS). The impact of 6-gingerol on pyroptosis was also examined. In addition, we assessed the role of MAPK signaling in 6-gingerol-induced effects in BMDMs and RAW264.7 cells. RESULTS: In CLP mice, 6-gingerol significantly ameliorated sepsis development, which was associated with the reduction of serum IL-1ß. In BMDMs and RAW264.7 cells, 6-gingerol strongly attenuated pyroptosis as well as the release of caspase-1p20, HMGB1, mature IL-1ß, IL-18 in response to ATP and LPS treatment. 6-Gingerol conferred these effects by blocking MAPK activation. Exposure to an ERK agonist (EGF) reversed effects of 6-gingerol, causing pyroptosis, LDH and caspase-1p20 release. CONCLUSIONS: By targeting MAPK signaling, 6-gingerol significantly suppressed secretion of pro-inflammatory cytokines and inhibited macrophage cells pyroptosis resulting in overall inhibition of sepsis development.


Assuntos
Catecóis/farmacologia , Citocinas/sangue , Álcoois Graxos/farmacologia , Macrófagos/efeitos dos fármacos , Piroptose/efeitos dos fármacos , Sepse/tratamento farmacológico , Trifosfato de Adenosina/farmacologia , Animais , Caspase 1/metabolismo , Catecóis/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Fator de Crescimento Epidérmico/farmacologia , Álcoois Graxos/uso terapêutico , Proteína HMGB1 , Interleucina-18/metabolismo , Interleucina-1beta/sangue , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Células RAW 264.7 , Sepse/metabolismo , Sepse/fisiopatologia
11.
Hepatology ; 65(1): 253-268, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27774630

RESUMO

Sterile liver inflammation, such as liver ischemia-reperfusion, hemorrhagic shock after trauma, and drug-induced liver injury, is initiated and regulated by endogenous mediators including DNA and reactive oxygen species. Here, we identify a mechanism for redox-mediated regulation of absent in melanoma 2 (AIM2) inflammasome activation in hepatocytes after redox stress in mice, which occurs through interaction with cytosolic high mobility group box 1 (HMGB1). We show that in liver during hemorrhagic shock in mice and in hepatocytes after hypoxia with reoxygenation, cytosolic HMGB1 associates with AIM2 and is required for activation of caspase-1 in response to cytosolic DNA. Activation of caspase-1 through AIM2 leads to subsequent hepatoprotective responses such as autophagy. HMGB1 binds to AIM2 at a non-DNA-binding site on the hematopoietic interferon-inducible nuclear antigen domain of AIM2 to facilitate inflammasome and caspase-1 activation in hepatocytes. Furthermore, binding of HMGB1 to AIM2 is stronger with fully reduced all-thiol HMGB1 than with partially oxidized disulfide-HMGB1, and binding strength corresponds to caspase-1 activation. These data suggest that HMGB1 redox status regulates AIM2 inflammasome activation. CONCLUSION: These findings suggest a novel and important mechanism for regulation of AIM2 inflammasome activation in hepatocytes during redox stress and may suggest broader implications for how this and other inflammasomes are activated and how their activation is regulated during cell stress, as well as the mechanisms of inflammasome regulation in nonimmune cell types. (Hepatology 2017;65:253-268).


Assuntos
Proteínas de Ligação a DNA/fisiologia , Hepatócitos/metabolismo , Inflamassomos/metabolismo , Hepatopatias/etiologia , Animais , Caspase 1/metabolismo , Proteína HMGB1/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução
12.
J Biol Chem ; 291(29): 15093-107, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27226571

RESUMO

The sensing of double-stranded RNA (dsRNA) in the liver is important for antiviral defenses but can also contribute to sterile inflammation during liver injury. Hepatocytes are often the target of viral infection and are easily injured by inflammatory insults. Here we sought to establish the pathways involved in the production of type I interferons (IFN-I) in response to extracellular poly(I:C), a dsRNA mimetic, in hepatocytes. This was of interest because hepatocytes are long-lived and, unlike most immune cells that readily die after activation with dsRNA, are not viewed as cells with robust antimicrobial capacity. We found that poly(I:C) leads to rapid up-regulation of inducible nitric oxide synthase (iNOS), double-stranded RNA-dependent protein kinase (PKR), and Src. The production of IFN-ß was dependent on iNOS, PKR, and Src and partially dependent on TLR3/Trif. iNOS and Src up-regulation was partially dependent on TLR3/Trif but entirely dependent on PKR. The phosphorylation of TLR3 on tyrosine 759 was shown to increase in parallel to IFN-ß production in an iNOS- and Src-dependent manner, and Src was found to directly interact with TLR3 in the endosomal compartment of poly(I:C)-treated cells. Furthermore, we identified a robust NO/cGMP/PKG-dependent feedforward pathway for the amplification of iNOS expression. These data identify iNOS/NO as an integral component of IFN-ß production in response to dsRNA in hepatocytes in a pathway that involves the coordinated activities of TLR3/Trif and PKR.


Assuntos
Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferon beta/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , RNA de Cadeia Dupla/imunologia , RNA de Cadeia Dupla/farmacologia , Receptor 3 Toll-Like/metabolismo , eIF-2 Quinase/metabolismo , Quinases da Família src/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/deficiência , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Células Cultivadas , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Hepatócitos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Óxido Nítrico Sintase Tipo II/deficiência , Óxido Nítrico Sintase Tipo II/genética , Fosforilação/efeitos dos fármacos , Poli I-C/farmacologia , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Receptor 3 Toll-Like/deficiência , Receptor 3 Toll-Like/genética , Tirosina/química , Regulação para Cima/efeitos dos fármacos , eIF-2 Quinase/deficiência , eIF-2 Quinase/genética , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/genética
13.
J Infect Dis ; 213(8): 1280-8, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26603204

RESUMO

BACKGROUND: Toll-like receptor 4 (TLR4) is a critical receptor involved in the sensing of gram-negative bacterial infection. However, the roles of TLR4 in sepsis are cell-type specific. Dendritic cells (DCs) are known to play a central role in microbial detection, alerting the immune system to the presence of infection and coordinating adaptive immune response. The goal of this study was to investigate the impact of DC-specific TLR4 signaling on host defense against intra-abdominal polymicrobial sepsis. METHODS: C57BL/6, global Tlr4 knockout, cell-specific knockout control, and CD11c-specific Tlr4(-/-) mice underwent cecal ligation and puncture (CLP). RESULTS: Specific deletion of TLR4 on DCs in mice improved survival and enhanced bacterial clearance. Deletion of TLR4 on DCs was associated with lower levels of circulating interleukin 10 (IL-10), higher polymorphonuclear leukocyte (PMN) accumulation in the peritoneal cavity, and higher expression of chemokine (C-X-C motif) receptor 2 (CXCR2) on PMNs after CLP. In vitro studies of DC and neutrophil cocultures confirmed that TLR4-dependent secretion of IL-10 from DCs regulated neutrophil CXCR2 expression. CONCLUSIONS: Our data shed light on a previously unrecognized role for TLR4 signaling on DCs in driving IL-10 secretion during sepsis and, through this pathway, regulates PMN recruitment via suppression of CXCR2 expression.


Assuntos
Células Dendríticas/metabolismo , Interleucina-10/metabolismo , Infecções Intra-Abdominais/imunologia , Receptores de Interleucina-8B/metabolismo , Sepse/imunologia , Receptor 4 Toll-Like/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
Front Chem ; 11: 1324469, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192499

RESUMO

Timely, convenient, and efficient detection of carbohydrate antigen 15-3 (CA15-3) levels in serum holds significant importance in early screening, diagnostic assistance and prognosis prediction of breast cancer. The development of efficient and convenient electrochemical aptasensors with immobilized redox probes for label-free detection of CA15-3 is highly desirable. In this work, a bipolar silica nanochannel array film (bp-SNA) with two distinct functional domains including nanochannels and an outer surface was employed for the immobilization of recognition ligands and electrochemical redox probes, enabling the construction of a probe-integrated aptasensor for reagentless electrochemical detection of CA15-3. Cost-effective and readily available indium tin oxide (ITO) was used as the supporting electrode for sequential growth of a negatively charged inner layer (n-SNA) followed by a positively charged outer layer (p-SNA). The preparation process of bp-SNA is convenient. Functionalization of amino groups on the outer surface of bp-SNA was modified by aldehyde groups for covalent immobilization of recognition aptamers, further establishing the recognition interface. Within the nanochannels of bp-SNA, the electrochemical redox probe, tri (2,2'-dipyridyl) cobalt (II) (Co(bpy)3 2+) was immobilized, which experienced a dual effect of electrostatic attraction from n-SNA and electrostatic repulsion from p-SNA, resulting in high stability of the immobilized probes. The constructed aptasensor allowed for reagentless electrochemical detection of CA15-3 ranged from 0.001 U/mL to 500 U/mL with a low detection limit (DL), 0.13 mU/mL). The application of the constructed aptasensor for CA15-3 detection in fetal bovine serum was also validated. This sensor offers advantages of a simple and readily obtainable supporting electrode, easy bp-SNA fabrication, high probe stability and good stability.

15.
Cell Cycle ; 22(3): 291-302, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36258646

RESUMO

Octamer-binding transcription factor 4 (Oct4) is closely related to the occurrence and development of cancer. In the present study, we paid a special interest in exploring the effect of Oct4 on colon cancer (CC) proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) and its molecular mechanism. Immunohistochemistry (IHC) was used to detect the expression level of Oct4 in colon tissue of patients with colon cancer. Oct4 overexpression vector pcDNA-Oct4 was used to stably express Oct4 in human colon cancer cells HT29 and SW480. Cell counting kit-8 (CCK-8) assay was used to detect the cell proliferation. The invasion and migration abilities were observed by transwell and wound healing assays. The expression of EMT relate genes were observed by Western blot. We found that Oct4 was up-regulated in human colon cancer tissues than that in paracancerous tissues. The proliferation, migration, and invasion of HT29 and SW480 cells was significantly induced by transfection of pcDNA-Oct4. Furthermore, Oct4 overexpression enhanced EMT of CC cells, characterized by the increased expression of vimentin, Twist, and Snail, as well as decreased expression of E-cadherin. Mechanistically, Oct4 overexpression activated stem cell factor (SCF)/c-Kit signaling pathway in CC cells, and the SCF/c-Kit signaling inhibitor imatinib reversed pro-oncogenic effects of Oct4. These finding provide an insight into the potential of Oct4 for CC diagnosis and therapy.


Assuntos
Neoplasias do Colo , Transição Epitelial-Mesenquimal , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias do Colo/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais
16.
IEEE Trans Biomed Eng ; 70(5): 1683-1691, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36441885

RESUMO

OBJECTIVE: Noninvasive fractional flow reserve (FFR) has been extensively studied and gained clinical recognition. However, the effect of an interventional catheter and a pressure wire in the arteries on the noninvasive FFR was not considered in previous studies. We provide quantitative analysis of how a catheter and a pressure wire can affect the estimation of noninvasive FFR using computational fluid dynamics (CFD) techniques. METHODS: Six patients are studied. We calibrate our CFD model with patient-specific conditions so that the noninvasive FFR matches the FFR measured by the pressure wire. Then, we numerically remove the pressure wire and compute the noninvasive FFR again. This allows us to analyze the effect of the pressure wire on FFR. RESULTS: The presence of a catheter and a pressure wire can reduce distal pressure from -0.1 mmHg to -8.1 mmHg, resulting in a reduction of FFR by 5.8 % in average (0.012 to 0.107 or -1.2 % to -16.8 %). The insertion also reduces the time-averaged flow rate at the stenosis by up to 16.2 % (4.9 % in average). CONCLUSION: The impact of the pressure wire on the measured FFR depends on the characteristics of the patient-specific lesion. Significant linear correlations are found between the minimum diameter of the stenotic arteries and the reduction in FFR. SIGNIFICANCE: The impact we found may contribute to provide a correction and improve the estimation of the noninvasive FFR technique for use in clinical practice.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Humanos , Angiografia Coronária/métodos , Vasos Coronários , Hemodinâmica , Valor Preditivo dos Testes , Índice de Gravidade de Doença
17.
MedComm (2020) ; 4(5): e398, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37829506

RESUMO

Sepsis is an often-deadly complication of infection that can lead to multiple organ failure. Previous studies have demonstrated that autophagy has a protective effect on liver injury in sepsis. Here, we report a novel long noncoding RNA (lncRNA), named lipopolysaccharide (LPS)-induced liver autophagy regulator (LILAR), which was highly induced in the liver tissues of endotoxemic mice. LILAR deficiency significantly increased the susceptibility of mice to LPS. In contrast, LILAR overexpression rescued the liver injury mediated by LILAR deficiency and increased the survival of LILAR knockout mice with endotoxemia. Autophagy-related protein 13 (Atg13) is a potential downstream target gene of LILAR. LILAR deficiency notably decreased Atg13 expression and suppressed autophagy in the livers of mice challenged with LPS. A reporter gene assay showed that LILAR competitively adsorbed miR-705 to increase the expression of Atg13 in cultured cells, indicating that LILAR participates in the regulation of the autophagy in the liver tissues of endotoxemic mice through a competitive endogenous RNA mechanism. In summary, we identified a novel lncRNA, LILAR, as a hepatic autophagy regulator, which not only promotes our understanding of liver pathophysiology but also provides a potential therapeutic target and/or diagnostic biomarker for liver injury in endotoxemia.

18.
Cell Host Microbe ; 31(5): 766-780.e7, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37100057

RESUMO

Acetaminophen (APAP) overdose is a leading cause of drug-induced liver injury (DILI). The impact of the gut microbiota and associated metabolites on APAP and liver function remains unclear. We show that APAP disturbance is associated with a distinct gut microbial community, with notable decreases in Lactobacillus vaginalis. Mice receiving L. vaginalis showed resistance to APAP hepatotoxicity due to the liberation of the isoflavone daidzein from the diet by bacterial ß-galactosidase. The hepatoprotective effects of L. vaginalis in APAP-exposed germ-free mice were abolished with a ß-galactosidase inhibitor. Similarly, ß-galactosidase-deficient L. vaginalis produced poorer outcomes in APAP-treated mice than the wild-type strain, but these differences were overcome with daidzein administration. Mechanistically, daidzein prevented ferroptotic death, which was linked to decreased expression of farnesyl diphosphate synthase (Fdps) that activated a key ferroptosis pathway involving AKT-GSK3ß-Nrf2. Thus, liberation of daidzein by L. vaginalis ß-galactosidase inhibits Fdps-mediated hepatocyte ferroptosis, providing promising therapeutic approaches for DILI.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Microbioma Gastrointestinal , Isoflavonas , Animais , Camundongos , Acetaminofen/farmacologia , beta-Galactosidase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Isoflavonas/farmacologia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2
19.
Inflammation ; 45(6): 2325-2338, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35701685

RESUMO

Liver injury induced by intestinal ischemia/reperfusion (I/R) is accompanied by the polarization of Kupffer cells, which are specialized macrophages located in the liver. However, the causes of hepatic macrophage polarization after intestinal I/R remain unknown. This study investigated whether gut-derived exosomes contribute to the pathogenesis of liver injury triggered by intestinal I/R in a murine model and explored the underlying mechanisms. Intestinal I/R models were established by temporally clamping the superior mesenteric arteries of mice. Exosomes were isolated from the intestinal tissue of mice that underwent intestinal I/R or sham surgery according to a centrifugation-based protocol. Exosomes were co-cultured with RAW 264.7 macrophages or injected intravenously in mice. Liposomal clodronate was administered intraperitoneally to deplete the macrophages. Macrophage polarization was determined by flow cytometry, immunohistochemistry, and quantitative polymerase chain reaction. Liver injury was assessed by histological morphology and increased serum aspartate aminotransferase and alanine aminotransferase levels. Exosomes from mice intestines subjected to I/R (IR-Exo) promoted macrophage activation in vitro. Intravenous injection of IR-Exo caused hepatic M1 macrophage polarization and led to liver injury in mice. Depleting macrophages ameliorated liver injury caused by intestinal I/R or the injection of IR-Exo. Furthermore, inhibiting exosome release improved intestinal injury, liver function, and survival rates of mice subjected to intestinal I/R. Our study provides evidence that gut-derived exosomes induce liver injury after intestinal I/R by promoting hepatic M1 macrophage polarization. Inhibition of exosome secretion could be a therapeutic target for preventing hepatic impairment after intestinal I/R.


Assuntos
Exossomos , Traumatismo por Reperfusão , Camundongos , Animais , Exossomos/patologia , Ativação de Macrófagos , Células de Kupffer/patologia , Traumatismo por Reperfusão/prevenção & controle , Fígado/patologia , Macrófagos/patologia , Reperfusão , Isquemia/complicações , Isquemia/patologia
20.
Front Genet ; 13: 1022626, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36685833

RESUMO

Background: Pancreatic adenocarcinoma (PAAD) is a highly deadly and aggressive tumour with a poor prognosis. However, the prognostic value of RNF169 and its related mechanisms in PAAD have not been elucidated. In this study, we aimed to explore prognosis-related genes, especially RNF169 in PAAD and to identify novel potential prognostic predictors of PAAD. Methods: The GEPIA and UALCAN databases were used to investigate the expression and prognostic value of RNF169 in PAAD. The correlation between RNF169 expression and immune infiltration was determined by using TIMER and TISIDB. Correlation analysis with starBase was performed to identify a potential regulatory axis of lncRNA-miRNA-RNF169. Results: The data showed that the level of RNF169 mRNA expression in PAAD tissues was higher than that in normal tissues. High RNF169 expression was correlated with poor prognosis in PAAD. In addition, analysis with the TISIDB and TIMER databases revealed that RNF169 expression was positively correlated with tumour immune infiltration in PAAD. Correlation analysis suggested that the long non-coding RNA (lncRNA) AL049555.1 and the microRNA (miRNA) hsa-miR-324-5p were involved in the expression of RNF169, composing a potential regulatory axis to control the progression of PAAD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that RNF169 plays a role in PAAD through pathways such as TNF, Hippo, JAK-STAT and Toll-like receptor signaling. Conclusion: In summary, the upregulation of RNF169 expression mediated by ncRNAs might influence immune cell infiltration in the microenvironment; thus, it can be used as a prognostic biomarker and a potential therapeutic target in PAAD.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA