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1.
Eur J Radiol ; 148: 110178, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35091166

RESUMO

PURPOSE: Differentiating the intrahepatic vascular type is essential for the early diagnosis of liver fibrosis. X-ray phase-contrast computed tomography (PCCT) is a label-free, high-resolution imaging modality for imaging vascular networks in a whole liver lobe. This study explores the use of three-dimensional (3D) branching geometry to differentiate between the hepatic vein (HV) and portal vein (PV) in early-stage liver fibrosis with PCCT. METHOD: Bile duct ligation surgery was conducted in mice to induce early-stage liver fibrosis. The individual liver lobes of mice were imaged using PCCT, and morphological characteristics, including vascular diameter, cross-sectional area, eccentricity, branch angle, bifurcation index, area ratio and junction exponent, were investigated in 3D modality. These characteristics were used to differentiate the HV from the PV, and their performance was evaluated through receiver operating characteristic (ROC) curve analysis. RESULTS: PCCT revealed a 3D vascular structure of the liver lobes. For intact lobes, the differentiation method between the HV and PV using the junction exponent had an AUC of 0.99 (95% CI: 0.98-1.00). Moreover, the AUCs of the junction exponent for 15, 10, and 5 branches in dissected lobes for differentiation were 0.98 (95% CI: 0.94-1.00), 0.86 (95% CI: 0.73-0.99) and 0.82 (95% CI: 0.67-0.97), respectively. CONCLUSION: The method of 3D branching geometry using the junction exponent could differentiate the HV from PV in early-stage liver fibrosis via the PCCT, which provides the foundation for further analysis of liver fibrosis.


Assuntos
Imageamento Tridimensional , Cirrose Hepática , Animais , Imageamento Tridimensional/métodos , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Camundongos , Tomografia Computadorizada por Raios X/métodos , Raios X
2.
FASEB J ; 35(10): e21918, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34569648

RESUMO

The role of LOXL1 in fibrosis via mediating ECM crosslinking and stabilization is well established; however, the role of hepatic stellate cells (HSCs)-specific LOXL1 in the development of fibrosis remains unknown. We generated HSCs-specific Loxl1-depleted mice (Loxl1Gfap-cre mice) to investigate the HSCs-specific contribution of LOXL1 in the pathogenesis of fibrosis. Loxl1fl/fl mice were used as the control. Furthermore, we used RNA sequencing to explore the underlying changes in the transcriptome. Results of the sirius red staining, type I collagen immunolabeling, and hydroxyproline content analysis, coupled with the reduced expression of profibrogenic genes revealed that Loxl1Gfap-cre mice with CCl4 -induced fibrosis exhibited decreased hepatic fibrosis. In addition, Loxl1Gfap-cre mice exhibited reduced macrophage tissue infiltration by CD68-positive cells and decreased expression of inflammatory genes compared with the controls. RNA sequencing identified integrin α8 (ITGA8) as a key modulator of LOXL1-mediated liver fibrosis. Functional analyses showed that siRNA silencing of Itga8 in cultured fibroblasts led to a decline in the LOXL1 expression and inhibition of fibroblast activation. Mechanistic analyses indicated that LOXL1 activated the FAK/PI3K/AKT/HIF1a signaling pathway, and the addition of inhibitors of FAK or PI3K reversed these results via downregulation of LOXL1. Furthermore, HIF1a directly interacted with LOXL1 and upregulated its expression, indicating that LOXL1 can positively self-regulate by forming a positive feedback loop with the FAK/PI3K/AKT/HIF1a pathway. We demonstrated that HSCs-specific Loxl1 deficiency prevented fibrosis, inflammation and that ITGA8/FAK/PI3K/AKT/HIF1a was essential for the function and expression of LOXL1. Knowledge of this approach can provide novel mechanisms and targets to treat fibrosis in the future.


Assuntos
Aminoácido Oxirredutases/deficiência , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Células 3T3 , Aminoácido Oxirredutases/biossíntese , Aminoácido Oxirredutases/genética , Animais , Sequência de Bases , Tetracloreto de Carbono/administração & dosagem , Tetracloreto de Carbono/efeitos adversos , Feminino , Fibroblastos/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Cirrose Hepática/patologia , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Regulação para Cima
3.
Front Pharmacol ; 12: 634115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163351

RESUMO

Objectives: Hepatic ischemia-reperfusion injury (HIRI) is of common occurrence during liver surgery and liver transplantation and may cause hepatic impairment, resulting in acute liver dysfunction. Nitrate plays an important physiological regulatory role in the human body. Whether dietary nitrate could prevent HIRI is, however, unknown. Methods: A HIRI mouse model was established in that the blood supply to the median lobe and left lateral lobe was blocked for 60 min through the portal vein and related structures using an atraumatic clip. Sodium nitrate (4 mM) was administrated in advance through drinking water to compare the influence of sodium nitrate and normal water on HIRI. Results: Liver necrosis and injury aggravated after HIRI. The group treated with sodium nitrate showed the lowest activities of plasma aminotransferase and lactate dehydrogenase and improved outcomes in histological investigation and TUNEL assay. Mechanistically, sodium nitrate intake increased plasma and liver nitric oxide levels, upregulated nuclear factor erythroid 2-related factor 2 (NRF2)-related molecules to reduce malondialdehyde level, and increased the activities of antioxidant enzymes to modulate hepatic oxidative stress. Conclusions: Dietary inorganic nitrate could prevent HIRI, possibly by activating the NRF2 pathway and modulating oxidative stress. Our study provides a novel therapeutic compound that could potentially prevent HIRI during liver transplantation or hepatic surgery.

4.
Nat Commun ; 12(1): 650, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510172

RESUMO

Hepatic inflammation is the driving force for the development and progression of NASH. Treatment targeting inflammation is believed to be beneficial. In this study, adoptive transfer of CD4+ T cells converted double negative T cells (cDNT) protects mice from diet-induced liver fat accumulation, lobular inflammation and focal necrosis. cDNT selectively suppress liver-infiltrating Th17 cells and proinflammatory M1 macrophages. IL-10 secreted by M2 macrophages decreases the survival and function of cDNT to protect M2 macrophages from cDNT-mediated lysis. NKG2A, a cell inhibitory molecule, contributes to IL-10 induced apoptosis and dampened suppressive function of cDNT. In conclusion, ex vivo-generated cDNT exert potent protection in diet induced obesity, type 2 diabetes and NASH. The improvement of outcome is due to the inhibition on liver inflammatory cells. This study supports the concept and the feasibility of potentially utilizing this autologous immune cell-based therapy for the treatment of NASH.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Macrófagos/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Transferência Adotiva/métodos , Animais , Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/terapia , Dieta Hiperlipídica/efeitos adversos , Progressão da Doença , Perfilação da Expressão Gênica/métodos , Inflamação/genética , Interleucina-10/metabolismo , Fígado/patologia , Macrófagos/classificação , Macrófagos/imunologia , Masculino , Camundongos Endogâmicos C57BL , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/terapia , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/terapia
5.
Br J Pharmacol ; 177(14): 3183-3196, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32133635

RESUMO

BACKGROUND AND PURPOSE: The innate and adaptive immune systems both play important roles in drug-induced liver injury (DILI). However, the crosstalk between the innate and adaptive immunity in DILI is largely unknown. Extensive crosstalk is likely mandated by co-stimulatory interactions between these immune systems. OX40 is a co-stimulatory molecule, but whether it regulates the intrahepatic immune response in DILI remains unknown. EXPERIMENTAL APPROACH: Acute liver injury was induced by paracetamol (acetaminophen), carbon tetrachloride (CCl4 ), and d-galactosamine/LPS (GalN/LPS) in wild-type (WT) and Ox40 knockout (KO) mice, and disease progress was compared. KEY RESULTS: Plasma OX40 levels were significantly increased and were augmented in intrahepatic CD4+ T cells after paracetamol, CCl4 , or GalN/LPS administration. Liver injury in Ox40-deficient mice was attenuated compared with that in WT mice. Compared with WT mice, hepatic infiltration of Th1 and Th17 cells and macrophages in Ox40 KO mice was reduced. Furthermore, adoptive transfer of Ox40 KO-CD4+ T cells to Rag1-/- mice resulted in alleviated liver injury compared with WT-CD4+ T-cell transfer, with reduced liver infiltration of macrophages and pro-inflammatory cytokine secretion. Moreover, OX40/Fc stimulation in vitro revealed that soluble OX40 enhanced the biological function of murine macrophages, including up-regulation of genes associated with inflammation and tissue infiltration. Finally, soluble OX40 levels were significantly elevated in DILI patients compared with healthy controls. CONCLUSION AND IMPLICATIONS: OX40 is a key molecule that promotes both pro-inflammatory macrophage and CD4+ T-cell function, exacerbating paracetamol-induced liver injury. OX40 could serve as a diagnostic index and therapeutic target of DILI.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Receptores OX40 , Animais , Galactosamina , Humanos , Fígado , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
6.
Histochem Cell Biol ; 154(1): 107-116, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32180004

RESUMO

The expression of epidermal growth factor (EGF) is increased during liver fibrogenesis, and EGF receptor (EGFR) antagonist could attenuate liver fibrosis. Since EGFR is highly expressed by hepatocytes and cholangiocytes in cirrhotic liver, whether hepatic stellate cells express EGFR in response to EGF still needs exploration. Although EGFR antagonist could attenuate liver fibrosis, many ligands with EGF-like domains, besides EGF, can function through EGFR. Whether specifically blocking EGF could attenuate bile duct ligation (BDL)-induced liver fibrosis has not been revealed. BDL induced biliary infarcts and matrix deposition in mouse liver, and EGFR was expressed and phosphorylated by α-smooth muscle actin (αSMA)-positive myofibroblasts. LX-2 cells expressed EGFR, and these receptors were phosphorylated in the in vitro culture system. Growth curve and cell cycle analysis revealed that EGF could enhance cell proliferation of LX-2 cells. In addition, administration of EGF antibodies markedly reduced the EGF level in serum and the deposition of extracellular matrix in the liver of BDL mice when compared to IgG administration. Administration of EGF antibodies also reduced the phosphorylation of EGFR and the percentage of Ki-67-positive or PCNA-positive liver myofibroblasts of BDL mice when compared to IgG administration. Therefore, activated hepatic stellate cells express EGFR, thus being responsive to EGF signal, and administration of EGF antibodies could attenuate liver fibrosis by restricting the proliferation of myofibroblasts.


Assuntos
Anticorpos/metabolismo , Ductos Biliares/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Miofibroblastos/metabolismo , Animais , Ductos Biliares/cirurgia , Proliferação de Células , Células Cultivadas , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Ligadura , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/patologia
7.
JCI Insight ; 4(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672934

RESUMO

Neutrophils play critical roles during the initial phase of hepatic ischemia/reperfusion injury (HIRI). However, the regulation of neutrophil activation, infiltration, and proinflammatory cytokine secretion has not been fully elucidated. In this study, we revealed that OX40 was expressed by neutrophils, its expression in neutrophils was time-dependently upregulated following HIRI, and Ox40 knockout markedly alleviated liver injury. Compared with wild-type neutrophils, the adoptive transfer of Ox40-/- neutrophils decreased HIRI in neutrophil-depleted Rag2/Il2rg-/- or Ox40-/- mice. Moreover, consistently, the in vitro experiments showed that Ox40 not only prolonged neutrophil survival but also promoted proinflammatory cytokines, ROS production, and even neutrophil chemotaxis. Further investigation demonstrated that the knockout of Ox40 in neutrophils inhibited NF-κB signaling via the TRAF1/2/4 and IKKα/IKKß/IκBα pathways. OX40L and OX86 stimulation could enhance neutrophil activation and survival in vitro and in vivo. In conclusion, our study provides a new understanding of OX40, which is expressed not only in adaptive immune cells but also in innate immune cells, i.e., neutrophils, contributing to the activation and survival of neutrophils. These findings provide a novel potential therapeutic target for the prevention of HIRI during liver transplantation or hepatic surgery.


Assuntos
Fígado/irrigação sanguínea , Neutrófilos/metabolismo , Receptores OX40/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Quimiotaxia de Leucócito , Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , Fígado/cirurgia , Transplante de Fígado , Camundongos , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Receptores OX40/genética
8.
Nat Commun ; 10(1): 4246, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31534137

RESUMO

Allergic asthma is an inflammatory disorder of the airway without satisfactory traditional therapies capable of controlling the underlying pathology. New approaches that can overcome the detrimental effects of immune dysregulation are thus desirable. Here we adoptively transfer ovalbumin (OVA) peptide-primed CD4-CD8- double negative T (DNT) cells intravenously into a mouse model of OVA-induced allergic asthma to find that OVA-induced airway hyperresponsiveness, lung inflammation, mucus production and OVA-specific IgG/IgE production are significantly suppressed. The immunosuppressive function of the OVA-specific DNT cells is dependent on the inhibition of CD11b+ dendritic cell function, T follicular helper cell proliferation, and IL-21 production. Mechanistically, Lag3 contributes to MHC-II antigen recognition and trogocytosis, thereby modulating the antigen-specific immune regulation by DNT cells. The effectiveness of ex vivo-generated allergen-specific DNT cells in alleviating airway inflammation thus supports the potential utilization of DNT cell-based therapy for the treatment of allergic asthma.


Assuntos
Antígenos CD/metabolismo , Asma/fisiopatologia , Asma/terapia , Hiper-Reatividade Brônquica/imunologia , Linfócitos T Reguladores/transplante , Células Th2/imunologia , Transferência Adotiva , Alérgenos/imunologia , Animais , Asma/induzido quimicamente , Asma/imunologia , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/terapia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Antígenos de Histocompatibilidade Classe II , Imunoglobulina E/biossíntese , Imunoglobulina G/biossíntese , Interleucinas/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina , Linfócitos T Reguladores/imunologia , Proteína do Gene 3 de Ativação de Linfócitos
9.
Gastroenterology ; 157(5): 1352-1367.e13, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31362006

RESUMO

BACKGROUND & AIMS: Activation of TGFB (transforming growth factor ß) promotes liver fibrosis by activating hepatic stellate cells (HSCs), but the mechanisms of TGFB activation are not clear. We investigated the role of ECM1 (extracellular matrix protein 1), which interacts with extracellular and structural proteins, in TGFB activation in mouse livers. METHODS: We performed studies with C57BL/6J mice (controls), ECM1-knockout (ECM1-KO) mice, and mice with hepatocyte-specific knockout of EMC1 (ECM1Δhep). ECM1 or soluble TGFBR2 (TGFB receptor 2) were expressed in livers of mice after injection of an adeno-associated virus vector. Liver fibrosis was induced by carbon tetrachloride (CCl4) administration. Livers were collected from mice and analyzed by histology, immunohistochemistry, in situ hybridization, and immunofluorescence analyses. Hepatocytes and HSCs were isolated from livers of mice and incubated with ECM1; production of cytokines and activation of reporter genes were quantified. Liver tissues from patients with viral or alcohol-induced hepatitis (with different stages of fibrosis) and individuals with healthy livers were analyzed by immunohistochemistry and in situ hybridization. RESULTS: ECM1-KO mice spontaneously developed liver fibrosis and died by 2 months of age without significant hepatocyte damage or inflammation. In liver tissues of mice, we found that ECM1 stabilized extracellular matrix-deposited TGFB in its inactive form by interacting with αv integrins to prevent activation of HSCs. In liver tissues from patients and in mice with CCl4-induced liver fibrosis, we found an inverse correlation between level of ECM1 and severity of fibrosis. CCl4-induced liver fibrosis was accelerated in ECM1Δhep mice compared with control mice. Hepatocytes produced the highest levels of ECM1 in livers of mice. Ectopic expression of ECM1 or soluble TGFBR2 in liver prevented fibrogenesis in ECM1-KO mice and prolonged their survival. Ectopic expression of ECM1 in liver also reduced the severity of CCl4-induced fibrosis in mice. CONCLUSIONS: ECM1, produced by hepatocytes, inhibits activation of TGFB and its activation of HSCs to prevent fibrogenesis in mouse liver. Strategies to increase levels of ECM1 in liver might be developed for treatment of fibrosis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Proteínas da Matriz Extracelular/metabolismo , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/prevenção & controle , Fígado/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Proteínas da Matriz Extracelular/deficiência , Proteínas da Matriz Extracelular/genética , Células Estreladas do Fígado/patologia , Hepatite Alcoólica/metabolismo , Hepatite Alcoólica/patologia , Hepatite Viral Humana/metabolismo , Hepatite Viral Humana/patologia , Humanos , Fígado/patologia , Cirrose Hepática Alcoólica/metabolismo , Cirrose Hepática Alcoólica/patologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATP
10.
Cell Rep ; 25(13): 3786-3799.e4, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30590049

RESUMO

Both innate and adaptive immune cells are involved in the pathogenesis of nonalcoholic steatohepatitis (NASH), but the crosstalk between innate and adaptive immunity is largely unknown. Here we show that compared with WT mice, OX40-/- mice exhibit decreased liver fat accumulation, lobular inflammation, and focal necrosis after feeding with diets that induce NASH. Mechanistically, OX40 deficiency suppresses Th1 and Th17 differentiation, and OX40 deficiency in T cells inhibits monocyte migration, antigen presentation, and M1 polarization. Soluble OX40 stimulation alone upregulates antigen presentation, chemokine receptor expression, and proinflammatory cytokine secretion by liver monocytes. Furthermore, plasma soluble OX40 levels are positively associated with NASH in humans, suggesting clinical relevance of the findings. In conclusion, we show a mechanism for T cell regulation of innate immune cells. OX40 is a key regulator of both intrahepatic innate and adaptive immunity, generates two-way signals, and promotes both proinflammatory monocyte and macrophage and T cell function, resulting in NASH development.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/patologia , Receptores OX40/metabolismo , Animais , Apresentação de Antígeno , Diferenciação Celular , Sobrevivência Celular , Citocinas/metabolismo , Regulação para Baixo , Humanos , Mediadores da Inflamação/metabolismo , Fígado/imunologia , Fígado/patologia , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Monócitos/patologia , Hepatopatia Gordurosa não Alcoólica/sangue , Receptores OX40/sangue , Receptores OX40/deficiência , Solubilidade , Linfócitos T/imunologia
11.
Int Immunopharmacol ; 65: 16-22, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30268799

RESUMO

Naïve CD4 T cells can be converted to double-negative regulatory T cells (DNT) by mature dendritic cells (mDCs) and IL-2 stimulation, with IL-2 enhancing the proliferation and Perforin expression of DNT. However, the molecules that affect the conversion of DNT are still not clear. Here, we investigated the effects of Ox40 on the conversion and function of DNT in vitro and in vivo without IL-2. We found that OX86 (an Ox40 agonist) increased the conversion rate of DNT but failed to enhance the suppressive function of DNT. Ox40 deficiency profoundly decreased the conversion rate and suppressive function of DNT. This suppression decline was caused by effects of Ox40 on proliferation and apoptosis independent of Perforin, Granzyme B and Fas ligand. Ox40 deficiency influenced the regulatory function of DNT through multiple signals, such as Cxcr3, Cd160 and Cd30, independently of Prf, Gzmb and Fasl. In conclusion, we elucidated that Ox40 promotes the conversion and maintenance of DNT. Ox40 deficiency reduced the regulatory function of DNT both in vitro and in vivo by regulating proliferation, apoptosis, and suppression-related genes.


Assuntos
Glicoproteínas de Membrana/metabolismo , Linfócitos T Reguladores/classificação , Fatores de Necrose Tumoral/metabolismo , Animais , Anticorpos Monoclonais , Apoptose/fisiologia , Proliferação de Células , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Ligante OX40 , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Fatores de Necrose Tumoral/genética
12.
Br J Pharmacol ; 175(24): 4480-4495, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30266038

RESUMO

BACKGROUND AND PURPOSE: Diethyldithiocarbamate (DDC) is a major metabolite of disulfiram that is a potential drug for alcoholism treatment. In the present study, we attempted to explore the possible effect of DDC on non-alcoholic fatty liver disease (NAFLD) and related fibrosis in vivo. EXPERIMENTAL APPROACH: C57BL/6 mice and Sprague Dawley (SD) rats received a methionine/choline-deficient (MCD) diet to establish the model of NAFLD with or without DDC treatment. The livers and serum were assessed for histological changes and parameters related to lipid metabolism, liver injury, inflammation and fibrosis. Apoptosis and macrophage related markers were assessed by immunohistochemistry (IHC). KEY RESULTS: DDC significantly reduced hepatic steatosis in rats with NAFLD, induced by the MCD diet. DDC reduced the oxidative stress and endoplasmic reticulum stress-related parameters in mice with non-alcoholic steatohepatitis, induced by the MCD diet. IHC for Bax and cleaved caspase-3 showed that DDC inhibited the apoptosis of hepatocytes in the liver. DDC significantly reduced ballooning and Mallory-Denk bodies (MDB) in hepatocytes, accompanied by suppression of serum alanine aminotransferase, aspartate aminotransferase and MDB formation-related genes. DDC significantly alleviated hepatic inflammation, accompanied by suppression of inflammation-related genes. DDC suppressed the infiltration of macrophages, particularly inducible NOS-positive pro-inflammatory macrophages. In addition, DDC significantly alleviated liver fibrosis. Microarray analyses showed that DDC strongly affected lipid metabolism and oxidative stress-related processes and pathways. CONCLUSION AND IMPLICATIONS: DDC improves hepatic steatosis, ballooning, inflammation and fibrosis in rodent models of NAFLD through modulating lipid metabolism and oxidative stress.


Assuntos
Ditiocarb/farmacologia , Fígado Gorduroso/tratamento farmacológico , Fibrose/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Fibrose/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley
13.
Cell Death Dis ; 9(6): 616, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29795285

RESUMO

CD4+ T-cell-converted CD4-CD8- double negative (cDNT) have strong suppressive activity in the maintenance of immune tolerance, whereas IL-2 promotes cDNT proliferation and enhances cDNT resistance to apoptosis. However, the intrinsic mechanisms that regulate the survival of cDNT are still unknown. Here we demonstrate that the OX40 molecule was highly expressed on cDNT. The expression of OX40 was necessary to promote proliferation and inhibit apoptosis of cDNT in vivo and in vitro. OX40 promoted the survival of cDNT by regulating the expression of Bcl-2, Bcl-xL, Survivin, and BCL2L11. Canonical NF-κB cell signaling played an important role in the transmission of essential division and survival signals through OX40 in cDNT. IL-2 promoted the survival of cDNT in part via elevating the expression of the OX40 molecule. IL-2 promoted OX40 expression via downregulating the PPARα expression. In conclusion, we elucidated that OX40 is a key molecule that regulates cDNT proliferation and survival. IL-2 promoted OX40 expression by downregulating the PPARα binding to the OX40 promoter, leading to the elevated expression of Bcl-2, Bcl-xL, and Survivin in cDNT, which finally resulted in the promoted proliferation and decreased apoptosis of cDNT.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Receptores OX40/metabolismo , Animais , Apoptose , Sequência de Bases , Proliferação de Células , Sobrevivência Celular , Regulação da Expressão Gênica , Interleucina-2/metabolismo , Masculino , Camundongos Endogâmicos C57BL , PPAR alfa/metabolismo , Survivina/metabolismo , Proteína bcl-X/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-29636776

RESUMO

Bismuth-containing quadruple therapy has been recommended as the first line of treatment in areas of high clarithromycin or metronidazole resistance. However, safety concerns of bismuth agents have long been raised. We first assessed the efficacy and safety of Wei Bi Mei granules, which are bismuth compounds consisting of three synthetic drugs and five medicinal herbs, compared to bismuth aluminate and colloidal bismuth subcitrate (CBS) in H. pylori-infected mouse model. We then used atomic fluorescence spectroscopy and autometallography to measure the accumulation of three bismuth agents in the brain, heart, liver, and kidneys in adult Sprague-Dawley rats. We also evaluated the safety of bismuth agents by conducting clinical biochemistry tests in blood samples of experimental animals. Wei Bi Mei granules exhibited the highest efficacy of anti-H. pylori activity and yielded the lowest bismuth accumulation when compared to CBS and bismuth aluminate. Our findings show that Wei Bi Mei granules are a safe Chinese medicinal herb with potent anti-H. pylori activity and can be considered as an alternative to current bismuth compounds. Thus, Wei Bi Mei granules merit further evaluation, particularly with regard to efficacy and safety when they are combined with other H. pylori eradication medications in the clinical setting.

15.
Stem Cell Res Ther ; 8(1): 183, 2017 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-28807057

RESUMO

BACKGROUND: Although they are expandable in vitro, hepatic progenitors are immature cells and share many immunomarkers with hepatocellular carcinoma, raising potential concerns regarding maltransformation after transplantation. This study investigated the effects of hepatic nuclear factor (HNF) 4α on the proliferation, migration, and maltransformation of hepatic progenitors and determined the feasibility of using these manipulated cells for transplantation. METHODS: The effects of HNF4α on rat hepatic progenitors (i.e. hepatic oval cells) were analyzed by HNF4α overexpression and HNF4α shRNA. Nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice injured by carbon chloride (CCl4) were then transplanted with control, HNF4α-overexpressing or HNF4α-suppressing hepatic oval cells. Finally, the engraftment of these cells in the recipient liver was analyzed. RESULTS: Rat hepatic progenitors (i.e. hepatic oval cells) expressed HNF4α, although less than that in hepatocytes. When HNF4α was overexpressed in these cells, the proliferation and migration of hepatic oval cells were reduced; but when HNF4α was suppressed by shRNA, the proliferation and migration, and even anchorage-independent growth, of these cells were accelerated. RNA microarray and gene functional analysis revealed that suppressing HNF4α not only impaired many biosynthesis and metabolism pathways of hepatocytes but also increased pathways for cancer. When transplanted into CCl4-injured NOD/SCID mice, few HNF4α-suppressing hepatic oval cells localized into the liver, while control cells and HNF4α-overexpressing cells engrafted into the liver and differentiated into albumin-positive hepatocytes. Interestingly, the hepatocytes derived from HNF4α-overexpressing cells were less migrative and expressed less c-Myc than the cells derived from control cells. CONCLUSION: HNF4α constrains proliferation, migration, and maltransformation of hepatic progenitors, and HNF4α-overexpressing hepatic progenitors serve as an optimal candidate for cell transplantation.


Assuntos
Movimento Celular , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Fator 4 Nuclear de Hepatócito/metabolismo , Fígado/patologia , Células-Tronco/metabolismo , Animais , Tetracloreto de Carbono , Proliferação de Células , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Hepatócitos/transplante , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos
16.
Ultrasound Med Biol ; 43(10): 2343-2351, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28705556

RESUMO

The goal of the work described here was to explore the cause of spleen stiffness (SS) in hepatic fibrogenesis and evaluate the value of SS in liver fibrosis (LF) staging. LF was induced with carbon tetrachloride (CCl4) in rats (n = 40). Supersonic shear wave imaging and contrast-enhanced ultrasound were performed to determine liver stiffness (LS), SS and splenic hemodynamics. SS, LS and free portal pressure exhibited moderate correlations with fibrosis stage (r = 0.744-0.835, p < 0.001). Time-intensity curves of contrast-enhanced ultrasound for the spleen were presented as decreasing peak intensity and slope of decrease, and increasing time to peak. Splenic sinus dilation and congestion were observed on histopathologic analysis. The area under the receiver operating characteristic curve of SS was higher than that of LS for differentiating LF stages 0-2 from stages 3-4 (Z = 2.293, p = 0.02). SS is a reliable diagnostic marker for the assessment of LF in the CCl4 model, especially for severe fibrosis. Elevated portal pressure is the cause of increasing SS.


Assuntos
Meios de Contraste , Técnicas de Imagem por Elasticidade/métodos , Aumento da Imagem/métodos , Cirrose Hepática/patologia , Baço/diagnóstico por imagem , Baço/patologia , Animais , Modelos Animais de Doenças , Fosfolipídeos , Pressão na Veia Porta/fisiologia , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Baço/fisiopatologia , Hexafluoreto de Enxofre
17.
Cell Mol Life Sci ; 74(20): 3827-3840, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28612217

RESUMO

Adaptive immunity plays a critical role in IR and T2DM development; however, the biological mechanisms linking T cell costimulation and glucose metabolism have not been fully elucidated. In this study, we demonstrated that the costimulatory molecule OX40 controls T cell activation and IR development. Inflammatory cell accumulation and enhanced proinflammatory gene expression, as well as high OX40 expression levels on CD4+ T cells, were observed in the adipose tissues of mice with diet-induced obesity. OX40-KO mice exhibited significantly less weight gain and lower fasting glucose levels than those of WT mice, without obvious adipose tissue inflammation. The effects of OX40 on IR are mechanistically linked to the promotion of T cell activation, Th1 cell differentiation and proliferation-as well as the attenuation of Treg suppressive activity and the enhancement of proinflammatory cytokine production-in adipose tissues. Furthermore, OX40 expression on T cells was positively associated with obesity in humans, suggesting that our findings are clinically relevant. In summary, our study revealed that OX40 in CD4+ T cells is crucial for adipose tissue inflammation and IR development. Therefore, the OX40 signaling pathway may be a new target for preventing or treating obesity-related IR and T2DM.


Assuntos
Tecido Adiposo/imunologia , Inflamação/imunologia , Resistência à Insulina , Obesidade/imunologia , Receptores OX40/imunologia , Tecido Adiposo/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Humanos , Inflamação/etiologia , Inflamação/genética , Ativação Linfocitária , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/complicações , Obesidade/genética , Receptores OX40/genética , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Regulação para Cima
18.
Antimicrob Agents Chemother ; 59(7): 3726-35, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25824219

RESUMO

Vancomycin is a preferred antibiotic for treating Clostridium difficile infection (CDI) and has been associated with a rate of recurrence of CDI of as high as 20% in treated patients. Recent studies have suggested that berberine, an alternative medical therapy for gastroenteritis and diarrhea, exhibits several beneficial effects, including induction of anti-inflammatory responses and restoration of the intestinal barrier function. This study investigated the therapeutic effects of berberine on preventing CDI relapse and restoring the gut microbiota in a mouse model. Berberine was administered through gavage to C57BL/6 mice with established CDI-induced intestinal injury and colitis. The disease activity index (DAI), mean relative weight, histopathology scores, and levels of toxins A and B in fecal samples were measured. An Illumina sequencing-based analysis of 16S rRNA genes was used to determine the overall structural change in the microbiota in the mouse ileocecum. Berberine administration significantly promoted the restoration of the intestinal microbiota by inhibiting the expansion of members of the family Enterobacteriaceae and counteracting the side effects of vancomycin treatment. Therapy consisting of vancomycin and berberine combined prevented weight loss, improved the DAI and the histopathology scores, and effectively decreased the mortality rate. Berberine prevented CDIs from relapsing and significantly improved survival in the mouse model of CDI. Our data indicate that a combination of berberine and vancomycin is more effective than vancomycin alone for treating CDI. One of the possible mechanisms by which berberine prevents a CDI relapse is through modulation of the gut microbiota. Although this conclusion was generated in the case of the mouse model, use of the combination of vancomycin and berberine and represent a novel therapeutic approach targeting CDI.


Assuntos
Antibacterianos/uso terapêutico , Berberina/uso terapêutico , Enterocolite Pseudomembranosa/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Vancomicina/uso terapêutico , Animais , Proteínas de Bactérias/análise , Toxinas Bacterianas/análise , Sequência de Bases , Clostridioides difficile/efeitos dos fármacos , Colite/microbiologia , Colite/patologia , DNA Bacteriano/genética , Modelos Animais de Doenças , Quimioterapia Combinada , Enterobacteriaceae/efeitos dos fármacos , Enterocolite Pseudomembranosa/microbiologia , Enterocolite Pseudomembranosa/prevenção & controle , Enterotoxinas/análise , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética , Distribuição Aleatória , Recidiva , Análise de Sequência de DNA , Vancomicina/efeitos adversos , Redução de Peso/efeitos dos fármacos
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